lua-resty-openssl

FFI-based OpenSSL binding for LuaJIT, supporting OpenSSL 3.0, 1.1 and 1.0.2 series

!Build Status !luarocks !opm

Description

lua-resty-openssl is a FFI-based OpenSSL binding library, currently supports OpenSSL 3.0.0, 1.1.1, 1.1.0 and 1.0.2 series.

Note: when using with OpenSSL 1.0.2, it's recommanded to not use this library with other FFI-based OpenSSL binding libraries to avoid potential mismatch of cdef.

Status

Production.

Synopsis

This library is greatly inspired by luaossl, while uses the naming conversion closer to original OpenSSL API. For example, a function called X509_set_pubkey in OpenSSL C API will expect to exist as resty.openssl.x509:set_pubkey. CamelCases are replaced to underscore_cases, for exmaple X509_set_serialNumber becomes resty.openssl.x509:set_serial_number. Another difference than luaossl is that errors are never thrown using error() but instead return as last parameter.

Each Lua table returned by new() contains a cdata object ctx. User are not supposed to manully setting ffi.gc or calling corresponding destructor of the ctx struct (like *_free functions).

resty.openssl

This meta module provides a version sanity check against linked OpenSSL library and returns all exported modules to a table.

    return {
      _VERSION = 'x.y.z',
      bn = require("resty.openssl.bn"),
      cipher = require("resty.openssl.cipher"),
      digest = require("resty.openssl.digest"),
      hmac = require("resty.openssl.hmac"),
      kdf = require("resty.openssl.kdf"),
      pkey = require("resty.openssl.pkey"),
      objects = require("resty.openssl.objects"),
      rand = require("resty.openssl.rand"),
      version = require("resty.openssl.version"),
      x509 = require("resty.openssl.x509"),
      altname = require("resty.openssl.x509.altname"),
      chain = require("resty.openssl.x509.chain"),
      csr = require("resty.openssl.x509.csr"),
      crl = require("resty.openssl.x509.crl"),
      extension = require("resty.openssl.x509.extension"),
      extensions = require("resty.openssl.x509.extensions"),
      name = require("resty.openssl.x509.name"),
      store = require("resty.openssl.x509.store"),
    }

Starting OpenSSL 3.0, `provider` is also available.

openssl.luaossl_compat

syntax: openssl.luaossl_compat()

Provides luaossl flavored API which uses camelCase naming; user can expect drop in replacement.

For example, pkey:get_parameters is mapped to pkey:getParameters.

Note that not all luaossl API has been implemented, please check readme for source of truth.

openssl.resty_hmac_compat

syntax: openssl.resty_hmac_compat()

Call this function before require("resty.hmac") to allow these two libraries play nice with each other. This function is not available with OpenSSL 1.0.

resty.openssl.version

A module to provide version info.

version_num

The OpenSSL version number.

version_text

The OpenSSL version text.

version.version

syntax: text = version.version(types)

Returns various OpenSSL version information. Available values for types are:

    VERSION
    CFLAGS
    BUILT_ON
    PLATFORM
    DIR
    ENGINES_DIR
    VERSION_STRING
    FULL_VERSION_STRING
    MODULES_DIR
    CPU_INFO

For OpenSSL prior to 1.1.x, only VERSION, CFLAGS, BUILT_ON, PLATFORM and DIR are supported. Please refer to OPENSSL_VERSION_NUMBER(3) for explanation of each type.

    local version = require("resty.openssl.version")
    ngx.say(string.format("%x", version.version_num))
    -- outputs "101000bf"
    ngx.say(version.version_text)
    -- outputs "OpenSSL 1.1.0k  28 May 2019"
    ngx.say(version.version(version.PLATFORM))
    -- outputs "darwin64-x86_64-cc"

version.info

syntax: text = version.info(types)

Returns various OpenSSL information. Available values for types are:

    INFO_ENGINES_DIR
    INFO_DSO_EXTENSION
    INFO_CPU_SETTINGS
    INFO_LIST_SEPARATOR
    INFO_DIR_FILENAME_SEPARATOR
    INFO_CONFIG_DIR
    INFO_SEED_SOURCE
    INFO_MODULES_DIR

This function is only available on OpenSSL 3.0. Please refer to OPENSSL_VERSION_NUMBER(3) for explanation of each type.

    local version = require("resty.openssl.version")
    ngx.say(version.version(version.INFO_DSO_EXTENSION))
    -- outputs ".so"

OPENSSL_30

A boolean indicates whether the linked OpenSSL is 3.0 series.

OPENSSL_11

A boolean indicates whether the linked OpenSSL is 1.1 series.

OPENSSL_10

A boolean indicates whether the linked OpenSSL is 1.0 series.

resty.openssl.pkey

Module to interact with private keys and public keys (EVP_PKEY).

Each key type may only support part of operations:

Key Type | Load existing key | Key generation | Encrypt/Decrypt | Sign/Verify | Key Exchange | ---------|----------|----------------|-----------------|-------------|---------- | RSA| Y | Y | Y | Y | | DH | Y | Y | | | Y | EC | Y | Y | | Y (ECDSA) | Y (ECDH) | Ed25519 | Y | Y | | Y (PureEdDSA) | | X25519 | Y | Y | | | Y (ECDH) | Ed448 | Y | Y | | Y (PureEdDSA) | | X448 | Y | Y | | | Y (ECDH) |

Ed25519, X25519, Ed448 and X448 keys are only supported since OpenSSL 1.1.0.

pkey.new

syntax: pk, err = pkey.new(config)

syntax: pk, err = pkey.new(string, opts?)

syntax: pk, err = pkey.new()

Function to generate a key pair, or load existing key in PEM or DER format.

1. Pass a config table to create a new PKEY pair. Which defaults to:

    locak key, err = pkey.new({
      type = 'RSA',
      bits = 2048,
      exp = 65537
    })

To generate EC or DH key, please refer to pkey.paramgen for possible values of config table. It's also possible to load a PEM-encoded EC or DH parameters for key generation:

    local dhparam = pkey.paramgen({
      type = 'DH',
      group = 'dh_1024_160'
    })
    -- OR
    -- local dhparam = io.read("dhparams.pem"):read("*a")
    
    local key, err = pkey.new({
      type = 'DH',
      param = dhparam,
    }) 

Other possible types are Ed25519, X25519, Ed448 and X448. No additional parameters can be set during key generation for those keys.

1. Pass a string of private or public key in PEM, DER or JWK format text; optionally accpet a table opts to explictly load format and key type. When loading a key in PEM format, passphrase or passphrase_cb may be provided to decrypt the key.

    pkey.new(pem_or_der_text, {
      format = "*", -- choice of "PEM", "DER", "JWK" or "*" for auto detect
      type = "*", -- choice of "pr" for privatekey, "pu" for public key and "*" for auto detect
      passphrase = "secret password", -- the PEM encryption passphrase
      passphrase_cb = function()
        return "secret password"
      end, -- the PEM encryption passphrase callback function
    }
    

• When loading JWK, make sure the encoded JSON text is passed in.

• Currently it's not supported to contraint type on JWK key, the parameters in provided JSON will decide if a private or public key is loaded.

• Only JWK with key type of RSA, P-256, P-384 and P-512 EC, Ed25519, X25519, Ed448 and X448 OKP keys are supported.

• Public key part for OKP keys (the x parameter) is always not honored and derived from private key part (the d parameter) if it's specified.

1. Pass nil to create a 2048 bits RSA key.

2. Pass a EVP_PKEY* pointer, to return a wrapped pkey instance. Normally user won't use this approach. User shouldn't free the pointer on their own, since the pointer is not copied.

pkey.istype

syntax: ok = pkey.istype(table)

Returns true if table is an instance of pkey. Returns false otherwise.

pkey.paramgen

syntax: pem_txt, err = pk.paramgen(config)

Generate parameters for EC or DH key and output as PEM-encoded text.

For EC key:

Parameter | Description -----------|------------- type | "EC" curve | EC curves. If omitted, default to "prime192v1". To see list of supported EC curves, use openssl ecparam -list_curves.

For DH key:

Parameter | Description -----------|------------- type | "DH" bits | Generate a new DH parameter with bits long prime. If omitted, default to 2048. Starting OpenSSL 3.0, only bits equal to 2048 is allowed. group | Use predefined groups instead of generating new one. bit will be ignored if group is set.

Possible values for group are:

• RFC7919 "ffdhe2048", "ffdhe3072", "ffdhe4096", "ffdhe6144", "ffdhe8192"

• RFC5114 "dh_1024_160", "dh_2048_224", "dh_2048_256"

• RFC3526 "modp_1536", "modp_2048", "modp_3072", "modp_4096", "modp_6144", "modp_8192"

    local pem, err = pkey.paramgen({
      type = 'EC',
      curve = 'prime192v1',
    })
    
    local pem, err = pkey.paramgen({
      type = 'DH',
      group = 'ffdhe4096',
    })

pkey:get_parameters

syntax: parameters, err = pk:get_parameters()

Returns a table containing the parameters of pkey instance.

pkey:set_parameters

syntax: ok, err = pk:set_parameters(params)

Set the parameters of the pkey from a table params. If the parameter is not set in the params table, it remains untouched in the pkey instance.

    local pk, err = require("resty.openssl.pkey").new()
    local parameters, err = pk:get_parameters()
    local e = parameters.e
    ngx.say(e:to_number())
    -- outputs 65537
    
    local ok, err = pk:set_parameters({
      e = require("resty.openssl.bn").from_hex("100001")
    })
    
    local ok, err = pk:set_parameters(parameters)

Parameters for RSA key:

Parameter | Description | Type -----------|-------------|------ n | modulus common to both public and private key | bn e | public exponent | bn d | private exponent | bn p | first factor of n | bn q | second factor of n | bn dmp1 | d mod (p - 1), exponent1 | bn dmq1 | d mod (q - 1), exponent2 | bn iqmp | (InverseQ)(q) = 1 mod p, coefficient | bn

Parameters for EC key:

Parameter | Description | Type -----------|-------------|----- private | private key | bn public | public key | bn x | x coordinate of the public key| bn y | y coordinate of the public key| bn group | the named curve group | [NID] as a number, when passed in as set_parameters(), it's also possible to use the text representation. This is different from luaossl where a EC_GROUP instance is returned.

It's not possible to set x, y with public at same time as x and y is basically another representation of public. Also currently it's only possible to set x and y at same time.

Parameters for DH key:

Parameter | Description | Type -----------|-------------|----- private | private key | bn public | public key | bn p | prime modulus | bn q | reference position | bn p | base generator | bn

Parameters for Curve25519 and Curve448 keys:

Parameter | Description | Type -----------|-------------|----- private | raw private key represented as bytes | string public | raw public key represented as bytes | string

pkey:get_key_type

syntax: obj, err = pk:get_key_type()

Returns a ASN1_OBJECT of key type of the private key as a table.

    local pkey, err = require("resty.openssl.pkey").new({type="X448"})
    
    ngx.say(require("cjson").encode(pkey:get_key_type()))
    -- outputs '{"ln":"X448","nid":1035,"sn":"X448","id":"1.3.101.111"}'

pkey:sign

syntax: signature, err = pk:sign(digest)

Perform a digest signing using the private key defined in pkey instance. The digest parameter must be a resty.openssl.digest instance or a string. Returns the signed text and error if any.

When passing a digest instance as digest parameter, it should not have been called final(), user should only use update().

For RSA and EC keys, passing a string as digest parameter does the SHA256 as digest method by default. For Ed25519 or Ed448 keys, this function does a PureEdDSA verification and requires digest to be the string that needs signing. No message digest is used for Ed keys.

For EC key, this function does a ECDSA signing.

Note that OpenSSL does not support EC digital signature (ECDSA) with the obsolete MD5 hash algorithm and will return error on this combination. See EVP_DigestSign(3) for a list of algorithms and associated public key algorithms.

    -- RSA and EC keys
    local pk, err = require("resty.openssl.pkey").new()
    local digest, err = require("resty.openssl.digest").new("SHA256")
    digest:update("dog")
    -- WRONG: 
    -- digest:final("dog")
    local signature, err = pk:sign(digest)
    -- uses SHA256 by default
    local signature, err = pk:sign("dog")
    ngx.say(ngx.encode_base64(signature))
    
    -- Ed25519 and Ed448 keys
    local pk, err = require("resty.openssl.pkey").new({
      type = "Ed25519",
    })
    local signature, err = pk:sign("23333")
    ngx.say(ngx.encode_base64(signature))

pkey:verify

syntax: ok, err = pk:verify(signature, digest)

Verify a signture (which can be the string returned by pkey:sign). The second argument must be a resty.openssl.digest instance that uses the same digest algorithm as used in sign or a string. ok returns true if verficiation is successful and false otherwise. Note when verfication failed err will not be set. For EC key, this function does a ECDSA verification.

For RSA and EC keys, passing a string as digest parameter uses the SHA256 as digest method by default. For Ed25519 or Ed448 keys, this function does a PureEdDSA verification and requires both signature and digest to be string. No message digest is used for Ed keys.

    -- RSA and EC keys
    local pk, err = require("resty.openssl.pkey").new()
    local digest, err = require("resty.openssl.digest").new("SHA256")
    digest:update("dog")
    -- WRONG:
    -- digest:final("dog")
    local signature, err = pk:sign(digest)
    -- uses SHA256 by default
    local signature, err = pk:sign("dog")
    ngx.say(ngx.encode_base64(signature))
    
    digest, err = require("resty.openssl.digest").new("SHA256")
    digest:update("dog")
    local ok, err = pk:verify(signature, digest)
    -- uses SHA256 by default
    local ok, err = pk:verify(signature, "dog")
    
    -- Ed25519 and Ed448 keys
    local pk, err = require("resty.openssl.pkey").new({
      type = "Ed25519",
    })
    local signature, err = pk:sign("23333")
    ngx.say(ngx.encode_base64(signature))
    

pkey:encrypt

syntax: cipher_txt, err = pk:encrypt(txt, padding?)

Encrypts plain text txt with pkey instance, which must loaded a public key.

When key is a RSA key, the function accepts an optional second argument padding which can be:

      pkey.PADDINGS = {
        RSA_PKCS1_PADDING       = 1,
        RSA_SSLV23_PADDING      = 2,
        RSA_NO_PADDING          = 3,
        RSA_PKCS1_OAEP_PADDING  = 4,
        RSA_X931_PADDING        = 5,
        RSA_PKCS1_PSS_PADDING   = 6,
      }

If omitted, padding is default to pkey.PADDINGS.RSA_PKCS1_PADDING.

pkey:decrypt

syntax: txt, err = pk:decrypt(cipher_txt, padding?)

Decrypts cipher text cipher_txt with pkey instance, which must loaded a private key.

The optional second argument padding has same meaning in pkey:encrypt.

    local pkey = require("resty.openssl.pkey")
    local privkey, err = pkey.new()
    local pub_pem = privkey:to_PEM("public")
    local pubkey, err = pkey.new(pub_pem)
    local s, err = pubkey:encrypt("🦢", pkey.PADDINGS.RSA_PKCS1_PADDING)
    ngx.say(#s)
    -- outputs 256
    local decrypted, err = privkey:decrypt(s)
    ngx.say(decrypted)
    -- outputs "🦢"

pkey:sign_raw

syntax: signature, err = pk:sign_raw(txt, padding?)

Signs the cipher text cipher_txt with pkey instance, which must loaded a private key.

The optional second argument padding has same meaning in pkey:encrypt.

This function may also be called "private encrypt" in some implementations like NodeJS or PHP. Do note as the function names suggested, this function is not secure to be regarded as an encryption. When developing new applications, user should use pkey:sign for signing with digest, or pkey:encrypt for encryption.

See examples/raw-sign-and-recover.lua for an example.

pkey:verify_recover

syntax: txt, err = pk:verify_recover(signature, padding?)

Verify the cipher text signature with pkey instance, which must loaded a public key, and also returns the original text being signed. This operation is only supported by RSA key.

The optional second argument padding has same meaning in pkey:encrypt.

This function may also be called "public decrypt" in some implementations like NodeJS or PHP.

See examples/raw-sign-and-recover.lua for an example.

pkey:derive

syntax: txt, err = pk:derive(peer_key)

Derive public key algorithm shared secret peer_key, which must be a pkey instance.

See examples/x25519-dh.lua for an example on how key exchange works for X25519 keys with DH algorithm.

pkey:tostring

syntax: txt, err = pk:tostring(private_or_public?, fmt?)

Outputs private key or public key of pkey instance in PEM-formatted text. The first argument must be a choice of public, PublicKey, private, PrivateKey or nil. The second argument fmt can be PEM, DER, JWK or nil. If both arguments are omitted, this functions returns the PEM representation of public key.

pkey:to_PEM

syntax: pem, err = pk:to_PEM(private_or_public?)

Equivalent to pk:tostring(private_or_public, "PEM").

resty.openssl.bn

Module to expose BIGNUM structure. Note bignum is a big integer, no float operations (like square root) are supported.

bn.new

syntax: b, err = bn.new(number?)

Creates a bn instance. The first argument can be a Lua number or nil to creates an empty instance.

bn.dup

syntax: b, err = bn.dup(bn_ptr_cdata)

Duplicates a BIGNUM* to create a new bn instance.

bn.istype

syntax: ok = bn.istype(table)

Returns true if table is an instance of bn. Returns false otherwise.

bn.from_binary, bn:to_binary

syntax: bn, err = bn.from_binary(bin)

syntax: bin, err = bn:to_binary()

Creates a bn instance from binary string.

Exports the BIGNUM value in binary string.

    local b, err = require("resty.openssl.bn").from_binary(ngx.decode_base64("WyU="))
    local bin, err = b:to_binary()
    ngx.say(ngx.encode_base64(bin))
    -- outputs "WyU="

bn.from_hex, bn:to_hex

syntax: bn, err = bn.from_hex(hex)

syntax: hex, err = bn:to_hex()

Creates a bn instance from hex encoded string. Note that the leading 0x should not be included. A leading - indicating the sign may be included.

Exports the bn instance to hex encoded string.

    local bn = require("resty.openssl.bn")
    local b = bn.from_hex("5B25")
    local hex, err = b:to_hex()
    ngx.say(hex)
    -- outputs "5B25"

bn.from_dec, bn:to_dec

syntax: bn, err = bn.from_dec(dec)

syntax: dec, err = bn:to_dec()

Creates a bn instance from decimal string. A leading - indicating the sign may be included.

Exports the bn instance to decimal string.

    local bn = require("resty.openssl.bn")
    local b = bn.from_dec("23333")
    local dec, err = b:to_dec()
    ngx.say(dec)
    -- outputs "23333"

bn:to_number

syntax: n, err = bn:to_number()

syntax: n, err = bn:tonumber()

Export the lowest 32 bits or 64 bits part (based on the ABI) of bn instance to a number. This is useful when user wants to perform bitwise operations.

    local bn = require("resty.openssl.bn")
    local b = bn.from_dec("23333")
    local n, err = b:to_number()
    ngx.say(n)
    -- outputs 23333
    ngx.say(type(n))
    -- outputs "number"

bn:__metamethods

Various mathematical operations can be performed as if it's a number.

    local bn = require("resty.openssl.bn")
    local a = bn.new(123456)
    local b = bn.new(222)
     -- the following returns a bn
    local r
    r = -a
    r = a + b
    r = a - b
    r = a * b
    r = a / b -- equal to bn:idiv, returns floor division
    r = a % b
    -- all operations can be performed between number and bignum
    r = a + 222
    r = 222 + a
    -- the following returns a bool
    local bool
    bool = a < b
    bool = a >= b
    -- compare between number will not work
    -- WRONG: bool = a < 222

bn:add, bn:sub, bn:mul, bn:div, bn:exp, bn:mod, bn:gcd

syntax: r = a:op(b)

syntax: r = bn.op(a, b)

Perform mathematical operations op.

• add: add

• sub: subtract

• mul: multiply

• div, idiv: floor division (division with rounding down to nearest integer)

• exp, pow: the b-th power of a, this function is faster than repeated a * a * ....

• mod: modulo

• gcd: the greatest common divider of a and b.

Note that add, sub, mul, div, mod is also available with +, -, *, /, % operaters. See "above section" for examples.

    local bn = require("resty.openssl.bn")
    local a = bn.new(123456)
    local b = bn.new(9876)
    local r
    -- the followings are equal
    r = a:add(b)
    r = bn.add(a, b)
    r = a:add(9876)
    r = bn.add(a, 9876)
    r = bn.add(123456, b)
    r = bn.add(123456, 9876)

bn:sqr

syntax: r = a:sqr()

syntax: r = bn.sqr(a)

Computes the 2-th power of a. This function is faster than r = a * a.

bn:mod_add, bn:mod_sub, bn:mod_mul, bn:mod_exp

syntax: r = a:op(b, m)

syntax: r = bn.op(a, b, m)

Perform modulo mathematical operations op.

• mod_add: adds a to b modulo m

• mod_sub: substracts b from a modulo m

• mod_mul: multiplies a by b and finds the non-negative remainder respective to modulus m

• mod_exp, mod_pow: computes a to the b-th power modulo m (r=a^b % m). This function uses less time and space than exp. Do not call this function when m is even and any of the parameters have the BN_FLG_CONSTTIME flag set.

    local bn = require("resty.openssl.bn")
    local a = bn.new(123456)
    local b = bn.new(9876)
    local r
    -- the followings are equal
    r = a:mod_add(b, 3)
    r = bn.mod_add(a, b, 3)
    r = a:mod_add(9876, 3)
    r = bn.mod_add(a, 9876, 3)
    r = bn.mod_add(123456, b, 3)
    r = bn.mod_add(123456, 9876, 3)

bn:mod_sqr

syntax: r = a:mod_sqr(m)

syntax: r = bn.mod_sqr(a, m)

Takes the square of a modulo m.

bn:lshift, bn:rshift

syntax: r = bn:lshift(bit)

syntax: r = bn.lshift(a, bit)

syntax: r = bn:rshift(bit)

syntax: r = bn.rshift(a, bit)

Bit shift a to bit bits.

bn:is_zero, bn:is_one, bn:is_odd, bn:is_word

syntax: ok = bn:is_zero()

syntax: ok = bn:is_one()

syntax: ok = bn:is_odd()

syntax: ok, err = bn:is_word(n)

Checks if bn is 0, 1, and odd number or a number n respectively.

bn:is_prime

syntax: ok, err = bn:is_prime(nchecks?)

Checks if bn is a prime number. Returns true if it is prime with an error probability of less than 0.25^nchecks and error if any. If omitted, nchecks is set to 0 which means to select number of iterations basedon the size of the number

> This function perform a Miller-Rabin probabilistic primality test with nchecks iterations. If nchecks == BN_prime_checks (0), a number of iterations is used that yields a false positive rate of at most 2^-64 for random input. The error rate depends on the size of the prime and goes down for bigger primes. The rate is 2^-80 starting at 308 bits, 2^-112 at 852 bits, 2^-128 at 1080 bits, 2^-192 at 3747 bits and 2^-256 at 6394 bits.

> When the source of the prime is not random or not trusted, the number of checks needs to be much higher to reach the same level of assurance: It should equal half of the targeted security level in bits (rounded up to the next integer if necessary). For instance, to reach the 128 bit security level, nchecks should be set to 64.

See also BN_is_prime(3).

resty.openssl.cipher

Module to interact with symmetric cryptography (EVP_CIPHER).

cipher.new

syntax: d, err = cipher.new(cipher_name)

Creates a cipher instance. cipher_name is a case-insensitive string of cipher algorithm name. To view a list of cipher algorithms implemented, use openssl list -cipher-algorithms.

cipher.istype

syntax: ok = cipher.istype(table)

Returns true if table is an instance of cipher. Returns false otherwise.

cipher:encrypt

syntax: s, err = cipher:encrypt(key, iv?, s, no_padding?, aead_aad?)

Encrypt the text s with key key and IV iv. Returns the encrypted text in raw binary string and error if any. Optionally accepts a boolean no_padding which tells the cipher to enable or disable padding and default to false (enable padding). If no_padding is true, the length of s must then be a multiple of the block size or an error will occur.

When using GCM or CCM mode or chacha20-poly1305 cipher, it's also possible to pass the Additional Authenticated Data (AAD) as the fifth argument.

This function is a shorthand of cipher:init, cipher:set_aead_aad (if appliable) then cipher:final.

cipher:decrypt

syntax: s, err = cipher:decrypt(key, iv?, s, no_padding?, aead_aad?, aead_tag?)

Decrypt the text s with key key and IV iv. Returns the decrypted text in raw binary string and error if any. Optionally accepts a boolean no_padding which tells the cipher to enable or disable padding and default to false (enable padding). If no_padding is true, the length of s must then be a multiple of the block size or an error will occur; also, padding in the decrypted text will not be removed.

When using GCM or CCM mode or chacha20-poly1305 cipher, it's also possible to pas the Additional Authenticated Data (AAD) as the fifth argument and authentication tag as the sixth argument.

This function is a shorthand of cipher:init, cipher:set_aead_aad (if appliable), cipher:set_aead_tag (if appliable) then cipher:final.

cipher:init

syntax: ok, err = cipher:init(key, iv?, opts?)

Initialize the cipher with key key and IV iv. The optional third argument is a table consists of:

    {
        is_encrypt = false,
        no_padding = false,
    }

Calling function is needed before cipher:update and cipher:final if the cipher is not being initialized already. But not cipher:encrypt and cipher:decrypt.

If you wish to reuse cipher instance multiple times, calling this function is necessary to clear the internal state of the cipher. The shorthand functions cipher:encrypt and cipher:decrypt already take care of initialization and reset.

cipher:update

syntax: s, err = cipher:update(partial, ...)

Updates the cipher with one or more strings. If the cipher has larger than block size of data to flush, the function will return a non-empty string as first argument. This function can be used in a streaming fashion to encrypt or decrypt continous data stream.

cipher:update_aead_aad

syntax: ok, err = cipher:update_aead_aad(aad)

Provides AAD data to the cipher, this function can be called more than one times.

cipher:get_aead_tag

syntax: tag, err = cipher:get_aead_tag(size?)

Gets the authentication tag from cipher with length specified as size. If omitted, a tag with length of half of the block size will be returned. The size cannot exceed block size.

This function can only be called after encryption is finished.

cipher:set_aead_tag

syntax: ok, err = cipher:set_aead_tag(tag)

Set the authentication tag of cipher with tag.

This function can only be called before decryption starts.

cipher:final

syntax: s, err = cipher:final(partial?)

Returns the encrypted or decrypted text in raw binary string, optionally accept one string to encrypt or decrypt.

    -- encryption
    local c, err = require("resty.openssl.cipher").new("aes256")
    c:init(string.rep("0", 32), string.rep("0", 16), {
        is_encrypt = true,
    })
    c:update("🦢")
    local cipher, err = c:final()
    ngx.say(ngx.encode_base64(cipher))
    -- outputs "vGJRHufPYrbbnYYC0+BnwQ=="
    -- OR:
    local c, err = require("resty.openssl.cipher").new("aes256")
    local cipher, err = c:encrypt(string.rep("0", 32), string.rep("0", 16), "🦢")
    ngx.say(ngx.encode_base64(cipher))
    -- outputs "vGJRHufPYrbbnYYC0+BnwQ=="
    
    -- decryption
    local encrypted = ngx.decode_base64("vGJRHufPYrbbnYYC0+BnwQ==")
    local c, err = require("resty.openssl.cipher").new("aes256")
    c:init(string.rep("0", 32), string.rep("0", 16), {
        is_encrypt = false,
    })
    c:update(encrypted)
    local cipher, err = c:final()
    ngx.say(cipher)
    -- outputs "🦢"
    -- OR:
    local c, err = require("resty.openssl.cipher").new("aes256")
    local cipher, err = c:decrypt(string.rep("0", 32), string.rep("0", 16), encrypted)
    ngx.say(cipher)
    -- outputs "🦢"

Note: in some implementations like libsodium or Java, AEAD ciphers append the tag (or MAC) at the end of encrypted ciphertext. In such case, user will need to manually cut off the tag with correct size(usually 16 bytes) and pass in the ciphertext and tag seperately.

See examples/aes-gcm-aead.lua for an example to use AEAD modes with authentication.

cipher:derive

syntax: key, iv, err = cipher:derive(key, salt?, count?, md?)

Derive a key and IV (if appliable) from given material that can be used in current cipher. This function is useful mainly to work with keys that were already derived from same algorithm. Newer applications should use a more modern algorithm such as PBKDF2 provided by kdf.derive.

count is the iteration count to perform. If it's omitted, it's set to 1. Note the recent version of openssl enc cli tool automatically use PBKDF2 if -iter is set to larger than 1, while this function will not. To use PBKDF2 to derive a key, please refer to kdf.derive.

md is the message digest name to use, it can take one of the values md2, md5, sha or sha1. If it's omitted, it's default to sha1.

    local cipher = require("resty.openssl.cipher").new("aes-128-cfb")
    local key, iv, err = cipher:derive("x")
    -- equivalent to `openssl enc -aes-128-cfb -pass pass:x -nosalt -P -md sha1`

resty.openssl.digest

Module to interact with message digest (EVP_MD_CTX).

digest.new

syntax: d, err = digest.new(digest_name?)

Creates a digest instance. digest_name is a case-insensitive string of digest algorithm name. To view a list of digest algorithms implemented, use openssl list -digest-algorithms.

If digest_name is omitted, it's default to sha1. Specially, the digest_name "null" represents a "null" message digest that does nothing: i.e. the hash it returns is of zero length.

digest.istype

syntax: ok = digest.istype(table)

Returns true if table is an instance of digest. Returns false otherwise.

digest:update

syntax: ok, err = digest:update(partial, ...)

Updates the digest with one or more strings.

digest:final

syntax: str, err = digest:final(partial?)

Returns the digest in raw binary string, optionally accept one string to digest.

    local d, err = require("resty.openssl.digest").new("sha256")
    d:update("🦢")
    local digest, err = d:final()
    ngx.say(ngx.encode_base64(digest))
    -- outputs "tWW/2P/uOa/yIV1gRJySJLsHq1xwg0E1RWCvEUDlla0="
    -- OR:
    local d, err = require("resty.openssl.digest").new("sha256")
    local digest, err = d:final("🦢")
    ngx.say(ngx.encode_base64(digest))
    -- outputs "tWW/2P/uOa/yIV1gRJySJLsHq1xwg0E1RWCvEUDlla0="

digest:reset

syntax: ok, err = digest:reset()

Reset the internal state of digest instance as it's just created by digest:new. It calls EVP_DigestInit_ex under the hood.

resty.openssl.hmac

Module to interact with hash-based message authentication code (HMAC_CTX).

hmac.new

syntax: h, err = hmac.new(key, digest_name?)

Creates a hmac instance. digest_name is a case-insensitive string of digest algorithm name. To view a list of digest algorithms implemented, use openssl list -digest-algorithms.

If digest_name is omitted, it's default to sha1.

hmac.istype

syntax: ok = hmac.istype(table)

Returns true if table is an instance of hmac. Returns false otherwise.

hmac:update

syntax: ok, err = hmac:update(partial, ...)

Updates the HMAC with one or more strings.

hmac:final

syntax: str, err = hmac:final(partial?)

Returns the HMAC in raw binary string, optionally accept one string to digest.

    local d, err = require("resty.openssl.hmac").new("goose", "sha256")
    d:update("🦢")
    local hmac, err = d:final()
    ngx.say(ngx.encode_base64(hmac))
    -- outputs "k2UcrRp25tj1Spff89mJF3fAVQ0lodq/tJT53EYXp0c="
    -- OR:
    local d, err = require("resty.openssl.hmac").new("goose", "sha256")
    local hmac, err = d:final("🦢")
    ngx.say(ngx.encode_base64(hmac))
    -- outputs "k2UcrRp25tj1Spff89mJF3fAVQ0lodq/tJT53EYXp0c="

hmac:reset

syntax: ok, err = hmac:reset()

Reset the internal state of hmac instance as it's just created by hmac:new. It calls HMAC_Init_ex under the hood.

resty.openssl.kdf

Module to interact with KDF (key derivation function).

kdf.derive

syntax: key, err = kdf.derive(options)

Derive a key from given material. Various KDFs are supported based on OpenSSL version:

• On OpenSSL 1.0.2 and later, PBKDF2([RFC 2898], [NIST SP 800-132]) is available.

• On OpenSSL 1.1.0 and later, HKDF([RFC 5869]), TLS1-PRF([RFC 2246], [RFC 5246] and [NIST SP 800-135 r1]) and scrypt([RFC 7914]) is available.

options is a table that contains:

| Key | Type | Description | Required or default | | ------------ | ---- | ----------- | ------ | | type | number | Type of KDF function to use, one of kdf.PBKDF2, kdf.SCRYPT, kdf.TLS1_PRF or kdf.HKDF | required | | outlen | number | Desired key length to derive | required | | pass | string | Initial key material to derive from | (empty string) | | salt | string | Add some salt | (empty string) | | md | string | Message digest method name to use, not effective for scrypt type | "sha1" | | pbkdf2_iter | number | PBKDF2 iteration count. RFC 2898 suggests an iteration count of at least 1000. Any value less than 1 is treated as a single iteration. | 1 | | hkdf_key | string | HKDF key | required | | hkdf_mode | number | HKDF mode to use, one of kdf.HKDEF_MODE_EXTRACT_AND_EXPAND, kdf.HKDEF_MODE_EXTRACT_ONLY or kdf.HKDEF_MODE_EXPAND_ONLY. This is only effective with OpenSSL >= 1.1.1. To learn about mode, please refer to EVP_PKEY_CTX_set1_hkdf_key(3). Note with kdf.HKDEF_MODE_EXTRACT_ONLY, outlen is ignored and the output will be fixed size of HMAC-<md>. | kdf.HKDEF_MODE_EXTRACT_AND_EXPAND| | hkdf_info | string | HKDF info value | (empty string) | | tls1_prf_secret | string | TLS1-PRF secret | required | | tls1_prf_seed | string | TLS1-PRF seed | required | | scrypt_maxmem | number | Scrypt maximum memory usage in bytes |32 * 1024 * 1024 | | scrypt_N | number | Scrypt CPU/memory cost parameter, must be a power of 2 | required | | scrypt_r | number | Scrypt blocksize parameter (8 is commonly used) | required | | scrypt_p | number | Scrypt parallelization parameter | required |

    local kdf = require("resty.openssl.kdf")
    local key, err = kdf.derive({
        type = kdf.PBKDF2,
        outlen = 16,
        pass = "1234567",
        md = "md5",
        pbkdf2_iter = 1000,
    })
    ngx.say(ngx.encode_base64(key))
    -- outputs "cDRFLQ7NWt+AP4i0TdBzog=="
    
    key, err = kdf.derive({
        type = kdf.SCRYPT,
        outlen = 16,
        pass = "1234567",
        scrypt_N = 1024,
        scrypt_r = 8,
        scrypt_p = 16,
    })
    ngx.say(ngx.encode_base64(key))
    -- outputs "9giFtxace5sESmRb8qxuOw=="

resty.openssl.objects

Helpfer module on ASN1_OBJECT.

objects.obj2table

syntax: tbl = objects.bytes(asn1_obj)

Convert a ASN1_OBJECT pointer to a Lua table where

    {
      id: OID of the object,
      nid: NID of the object,
      sn: short name of the object,
      ln: long name of the object,
    }

objects.nid2table

syntax: tbl, err = objects.nid2table(nid)

Convert a [NID] to a Lua table, returns the same format as objects.obj2table

objects.txt2nid

syntax: nid, err = objects.txt2nid(txt)

Convert a text representation to [NID].

resty.openssl.rand

Module to interact with random number generator.

rand.bytes

syntax: str, err = rand.bytes(length)

Generate random bytes with length of length.

resty.openssl.x509

Module to interact with X.509 certificates.

x509.new

syntax: crt, err = x509.new(txt?, fmt?)

Creates a x509 instance. txt can be PEM or DER formatted text; fmt is a choice of PEM, DER to load specific format, or * for auto detect.

When txt is omitted, new() creates an empty x509 instance.

x509.dup

syntax: x509, err = x509.dup(x509_ptr_cdata)

Duplicates a X509* to create a new x509 instance.

x509.istype

syntax: ok = x509.istype(table)

Returns true if table is an instance of x509. Returns false otherwise.

x509:digest

syntax: d, err = x509:digest(digest_name?)

Returns a digest of the DER representation of the X509 certificate object in raw binary text.

digest_name is a case-insensitive string of digest algorithm name. To view a list of digest algorithms implemented, use openssl list -digest-algorithms.

If digest_name is omitted, it's default to sha1.

x509:pubkey_digest

syntax: d, err = x509:pubkey_digest(digest_name?)

Returns a digest of the DER representation of the pubkey in the X509 object in raw binary text.

digest_name is a case-insensitive string of digest algorithm name. To view a list of digest algorithms implemented, use openssl list -digest-algorithms.

If digest_name is omitted, it's default to sha1.

x509:get_, x509:set_

syntax: ok, err = x509:set_attribute(instance)

syntax: instance, err = x509:get_attribute()

Setters and getters for x509 attributes share the same syntax.

| Attribute name | Type | Description | | ------------ | ---- | ----------- | | issuer_name | x509.name | Issuer of the certificate | | not_before | number | Unix timestamp when certificate is not valid before | | not_after | number | Unix timestamp when certificate is not valid after | | pubkey | pkey | Public key of the certificate | | serial_number | bn | Serial number of the certficate | | subject_name | x509.name | Subject of the certificate | | version | number | Version of the certificate, value is one less than version. For example, 2 represents version 3 |

Additionally, getters and setters for extensions are also available:

| Extension name | Type | Description | | ------------ | ---- | ----------- | | subject_alt_name | x509.altname | Subject Alternative Name of the certificate, SANs are usually used to define "additional Common Names" | | issuer_alt_name | x509.altname | Issuer Alternative Name of the certificate | | basic_constraints | table, { ca = bool, pathlen = int} | Basic Constriants of the certificate | | info_access | x509.extension.info_access | Authority Information Access of the certificate, contains information like OCSP reponder URL. | | crl_distribution_points | x509.extension.dist_points | CRL Distribution Points of the certificate, contains information like Certificate Revocation List(CRL) URLs. |

For all extensions, get_{extension}_critical and set_{extension}_critical is also supported to access the critical flag of the extension.

If the attribute is not found, getter will return nil, nil.

    local x509, err = require("resty.openssl.x509").new()
    err = x509:set_not_before(ngx.time())
    local not_before, err = x509:get_not_before()
    ngx.say(not_before)
    -- outputs 1571875065
    
    err = x509:set_basic_constraints_critical(true)

If type is a table, setter requires a table with case-insensitive keys to set; getter returns the value of the given case-insensitive key or a table of all keys if no key provided.

    local x509, err = require("resty.openssl.x509").new()
    err = x509:set_basic_constraints({
      cA = false,
      pathlen = 0,
    })
    
    ngx.say(x509:get_basic_constraints("pathlen"))
    -- outputs 0
    
    ngx.say(x509:get_basic_constraints())
    -- outputs '{"ca":false,"pathlen":0}'

Note that user may also access the certain extension by x509:get_extension and x509:set_extension, while the later two function returns or requires extension instead. User may use getter and setters listed here if modification of current extensions is needed; use x509:get_extension or x509:set_extension if user are adding or replacing the whole extension or getters/setters are not implemented. If the getter returned a type of x509.* instance, it can be converted to a extension instance by extension:from_data, and thus used by x509:get_extension and x509:set_extension

x509:get_lifetime

syntax: not_before, not_after, err = x509:get_lifetime()

A shortcut of x509:get_not_before plus x509:get_not_after

x509:set_lifetime

syntax: ok, err = x509:set_lifetime(not_before, not_after)

A shortcut of x509:set_not_before plus x509:set_not_after.

x509:get_extension

syntax: extension, pos, err = x509:get_extension(nid_or_txt, last_pos?)

Get X.509 extension matching the given [NID] to certificate, returns a resty.openssl.x509.extension instance and the found position.

If last_pos is defined, the function searchs from that position; otherwise it finds from beginning. Index is 1-based.

    local ext, pos, err = x509:get_extension("keyUsage")
    ngx.say(ext:text())
    -- outputs "Digital Signature, Key Encipherment"
    
    local ext, pos, err = x509:get_extension("subjectKeyIdentifier")
    ngx.say(ext:text())
    -- outputs "3D:42:13:57:8F:79:BE:30:7D:86:A9:AC:67:50:E5:56:3E:0E:AF:4F"

x509:add_extension

syntax: ok, err = x509:add_extension(extension)

Adds an X.509 extension to certificate, the first argument must be a resty.openssl.x509.extension instance.

    local extension, err = require("resty.openssl.x509.extension").new(
      "keyUsage", "critical,keyCertSign,cRLSign"
    )
    local x509, err = require("resty.openssl.x509").new()
    local ok, err = x509:add_extension(extension)

x509:set_extension

syntax: ok, err = x509:set_extension(extension, last_pos?)

Adds an X.509 extension to certificate, the first argument must be a resty.openssl.x509.extension instance. The difference from x509:add_extension is that in this function if a extension with same type already exists, the old extension will be replaced.

If last_pos is defined, the function replaces the same extension from that position; otherwise it finds from beginning. Index is 1-based. Returns nil, nil if not found.

Note this function is not thread-safe.

x509:get_extension_critical

syntax: ok, err = x509:get_extension_critical(nid_or_txt)

Get critical flag of the X.509 extension matching the given [NID] from certificate.

x509:set_extension_critical

syntax: ok, err = x509:set_extension_critical(nid_or_txt, crit?)

Set critical flag of the X.509 extension matching the given [NID] to certificate.

x509:get_ocsp_url

syntax: url_or_urls, err = x509:get_ocsp_url(return_all?)

Get OCSP URL(s) of the X.509 object. If return_all is set to true, returns a table containing all OCSP URLs; otherwise returns a string with first OCSP URL found. Returns nil if the extension is not found.

x509:get_crl_url

syntax: url_or_urls, err = x509:get_crl_url(return_all?)

Get CRL URL(s) of the X.509 object. If return_all is set to true, returns a table containing all CRL URLs; otherwise returns a string with first CRL URL found. Returns nil if the extension is not found.

x509:sign

syntax: ok, err = x509:sign(pkey, digest?)

Sign the certificate using the private key specified by pkey, which must be a resty.openssl.pkey that stores private key. Optionally accept digest parameter to set digest method, whichmust be a resty.openssl.digest instance. Returns a boolean indicating if signing is successful and error if any.

x509:verify

syntax: ok, err = x509:verify(pkey)

Verify the certificate signature using the public key specified by pkey, which must be a resty.openssl.pkey. Returns a boolean indicating if verification is successful and error if any.

x509:tostring

syntax: str, err = x509:tostring(fmt?)

Outputs certificate in PEM-formatted text or DER-formatted binary. The first argument can be a choice of PEM or DER; when omitted, this function outputs PEM by default.

x509:to_PEM

syntax: pem, err = x509:to_PEM()

Outputs the certificate in PEM-formatted text.

resty.openssl.x509.csr

Module to interact with certificate signing request (X509_REQ).

See examples/csr.lua for an example to generate CSR.

csr.new

syntax: csr, err = csr.new(txt?, fmt?)

Create an empty csr instance. txt can be PEM or DER formatted text; fmt is a choice of PEM, DER to load specific format, or * for auto detect.

When txt is omitted, new() creates an empty csr instance.

csr.istype

syntax: ok = csr.istype(table)

Returns true if table is an instance of csr. Returns false otherwise.

csr:get_, csr:set_

syntax: ok, err = csr:set_attribute(instance)

syntax: instance, err = csr:get_attribute()

Setters and getters for x509 attributes share the same syntax.

| Attribute name | Type | Description | | ------------ | ---- | ----------- | | pubkey | pkey | Public key of the certificate request | | subject_name | x509.name | Subject of the certificate request | | version | number | Version of the certificate request, value is one less than version. For example, 2 represents version 3 |

Additionally, getters and setters for extensions are also available:

| Extension name | Type | Description | | ------------ | ---- | ----------- | | subject_alt_name | x509.altname | Subject Alternative Name of the certificate request, SANs are usually used to define "additional Common Names" |

For all extensions, get_{extension}_critical and set_{extension}_critical is also supported to access the critical flag of the extension.

If the attribute is not found, getter will return nil, nil.

    local csr, err = require("resty.openssl.csr").new()
    err = csr:set_version(3)
    local version, err = csr:get_version()
    ngx.say(version)
    -- outputs 3

Note that user may also access the certain extension by csr:get_extension and csr:set_extension, while the later two function returns or requires extension instead. User may use getter and setters listed here if modification of current extensions is needed; use csr:get_extension or csr:set_extension if user are adding or replacing the whole extension or getters/setters are not implemented. If the getter returned a type of x509.* instance, it can be converted to a extension instance by extension:from_data, and thus used by csr:get_extension and csr:set_extension

csr:set_subject_alt

Same as csr:set_subject_alt_name, this function is deprecated to align with naming convension with other functions.

csr:get_extension

syntax: extension, pos, err = csr:get_extension(nid_or_txt, pos?)

Get X.509 extension matching the given [NID] to certificate, returns a resty.openssl.x509.extension instance and the found position.

If last_pos is defined, the function searchs from that position; otherwise it finds from beginning. Index is 1-based.

    local ext, pos, err = csr:get_extension("basicConstraints")

csr:get_extensions

syntax: extensions, err = csr:get_extensions()

Return all extensions as a resty.openssl.x509.extensions instance.

csr:add_extension

syntax: ok, err = csr:add_extension(extension)

Adds an X.509 extension to csr, the first argument must be a resty.openssl.x509.extension instance.

csr:set_extension

syntax: ok, err = csr:set_extension(extension)

Adds an X.509 extension to csr, the first argument must be a resty.openssl.x509.extension instance. The difference from csr:add_extension is that in this function if a extension with same type already exists, the old extension will be replaced.

Note this function is not thread-safe.

csr:get_extension_critical

syntax: ok, err = csr:get_extension_critical(nid_or_txt)

Get critical flag of the X.509 extension matching the given [NID] from csr.

csr:set_extension_critical

syntax: ok, err = csr:set_extension_critical(nid_or_txt, crit?)

Set critical flag of the X.509 extension matching the given [NID] to csr.

csr:sign

syntax: ok, err = csr:sign(pkey, digest?)

Sign the certificate request using the private key specified by pkey, which must be a resty.openssl.pkey that stores private key. Optionally accept digest parameter to set digest method, whichmust be a resty.openssl.digest instance. Returns a boolean indicating if signing is successful and error if any.

csr:verify

syntax: ok, err = csr:verify(pkey)

Verify the CSR signature using the public key specified by pkey, which must be a resty.openssl.pkey. Returns a boolean indicating if verification is successful and error if any.

csr:tostring

syntax: str, err = csr:tostring(fmt?)

Outputs certificate request in PEM-formatted text or DER-formatted binary. The first argument can be a choice of PEM or DER; when omitted, this function outputs PEM by default.

csr:to_PEM

syntax: pem, err = csr:to_PEM(?)

Outputs CSR in PEM-formatted text.

resty.openssl.crl

Module to interact with X509_CRL(certificate revocation list).

crl.new

syntax: crt, err = crl.new(txt?, fmt?)

Creates a crl instance. txt can be PEM or DER formatted text; fmt is a choice of PEM, DER to load specific format, or * for auto detect.

When txt is omitted, new() creates an empty crl instance.

crl.dup

syntax: crl, err = crl.dup(crl_ptr_cdata)

Duplicates a X509_CRL* to create a new crl instance.

crl.istype

syntax: ok = crl.istype(table)

Returns true if table is an instance of crl. Returns false otherwise.

crl:get_, crl:set_

syntax: ok, err = crl:set_attribute(instance)

syntax: instance, err = crl:get_attribute()

Setters and getters for crl attributes share the same syntax.

| Attribute name | Type | Description | | ------------ | ---- | ----------- | | issuer_name | x509.name | Issuer of the CRL | | last_update | number | Unix timestamp when CRL is not valid before | | next_update | number | Unix timestamp when CRL is not valid after | | version | number | Version of the certificate, value is one less than version. For example, 2 represents version 3 |

Additionally, getters and setters for extensions are also available:

| Extension name | Type | Description | | ------------ | ---- | ----------- |

For all extensions, get_{extension}_critical and set_{extension}_critical is also supported to access the critical flag of the extension.

If the attribute is not found, getter will return nil, nil.

    local crl, err = require("resty.openssl.crl").new()
    err = crl:set_next_update(ngx.time())
    local not_before, err = crl:get_next_update()
    ngx.say(not_before)
    -- outputs 1571875065

Note that user may also access the certain extension by crl:get_extension and crl:set_extension, while the later two function returns or requires extension instead. User may use getter and setters listed here if modification of current extensions is needed; use crl:get_extension or crl:set_extension if user are adding or replacing the whole extension or getters/setters are not implemented. If the getter returned a type of crl.* instance, it can be converted to a extension instance by extension:from_data, and thus used by crl:get_extension and crl:set_extension

crl:get_extension

syntax: extension, pos, err = crl:get_extension(nid_or_txt, last_pos?)

Get X.509 extension matching the given [NID] to CRL, returns a resty.openssl.x509.extension instance and the found position.

If last_pos is defined, the function searchs from that position; otherwise it finds from beginning. Index is 1-based.

crl:add_extension

syntax: ok, err = crl:add_extension(extension)

Adds an X.509 extension to CRL, the first argument must be a resty.openssl.x509.extension instance.

crl:set_extension

syntax: ok, err = crl:set_extension(extension, last_pos?)

Adds an X.509 extension to CRL, the first argument must be a resty.openssl.x509.extension instance. The difference from crl:add_extension is that in this function if a extension with same type already exists, the old extension will be replaced.

If last_pos is defined, the function replaces the same extension from that position; otherwise it finds from beginning. Index is 1-based. Returns nil, nil if not found.

Note this function is not thread-safe.

crl:get_extension_critical

syntax: ok, err = crl:get_extension_critical(nid_or_txt)

Get critical flag of the X.509 extension matching the given [NID] from CRL.

crl:set_extension_critical

syntax: ok, err = crl:set_extension_critical(nid_or_txt, crit?)

Set critical flag of the X.509 extension matching the given [NID] to CRL.

crl:add_revoked

syntax: ok, err = crl:add_revoked(revoked)

Adds a resty.openssl.x509.revoked instance to the CRL.

crl:sign

syntax: ok, err = crl:sign(pkey, digest?)

Sign the CRL using the private key specified by pkey, which must be a resty.openssl.pkey that stores private key. Optionally accept digest parameter to set digest method, whichmust be a resty.openssl.digest instance. Returns a boolean indicating if signing is successful and error if any.

crl:verify

syntax: ok, err = crl:verify(pkey)

Verify the CRL signature using the public key specified by pkey, which must be a resty.openssl.pkey. Returns a boolean indicating if verification is successful and error if any.

crl:tostring

syntax: str, err = crl:tostring(fmt?)

Outputs CRL in PEM-formatted text or DER-formatted binary. The first argument can be a choice of PEM or DER; when omitted, this function outputs PEM by default.

crl:to_PEM

syntax: pem, err = crl:to_PEM()

Outputs the CRL in PEM-formatted text.

resty.openssl.x509.name

Module to interact with X.509 names.

name.new

syntax: name, err = name.new()

Creates an empty name instance.

name.dup

syntax: name, err = name.dup(name_ptr_cdata)

Duplicates a X509_NAME* to create a new name instance.

name.istype

syntax: ok = name.istype(table)

Returns true if table is an instance of name. Returns false otherwise.

name:add

syntax: name, err = name:add(nid_text, txt)

Adds an ASN.1 object to name. First arguments in the text representation of [NID]. Second argument is the plain text value for the ASN.1 object.

Returns the name instance itself on success, or nil and an error on failure.

This function can be called multiple times in a chained fashion.

    local name, err = require("resty.openssl.x509.name").new()
    local _, err = name:add("CN", "example.com")
    
    _, err = name
        :add("C", "US")
        :add("ST", "California")
        :add("L", "San Francisco")
    

name:find

syntax: obj, pos, err = name:find(nid_text, last_pos?)

Finds the ASN.1 object with the given text representation of [NID] from the postition of last_pos. By omitting the last_pos parameter, find finds from the beginning.

Returns the object in a table as same format as decribed here, the position of the found object and error if any. Index is 1-based. Returns nil, nil if not found.

    local name, err = require("resty.openssl.x509.name").new()
    local _, err = name:add("CN", "example.com")
                        :add("CN", "example2.com")
    
    local obj, pos, err = name:find("CN")
    ngx.say(obj.blob, " at ", pos)
    -- outputs "example.com at 1"
    local obj, pos, err = name:find("2.5.4.3", 1)
    ngx.say(obj.blob, " at ", pos)
    -- outputs "example2.com at 2"

name:tostring

syntax: txt = name:tostring()

Outputs name in a text representation.

    local name, err = require("resty.openssl.x509.name").new()
    local _, err = name:add("CN", "example.com")
                        :add("CN", "example2.com")
    
    ngx.say(name:tostring())
    -- outputs "CN=example.com/CN=example2.com"

name:__metamethods

syntax: for k, obj in pairs(name)

syntax: len = #name

syntax: k, v = name[i]

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with -DLUAJIT_ENABLE_LUA52COMPAT flag; otherwise use all, each, index and count instead.

See also "functions for stack-like objects".

Each returned object is a table where:

    {
      id: OID of the object,
      nid: NID of the object,
      sn: short name of the object,
      ln: long name of the object,
      blob: value of the object,
    }


    local name, err = require("resty.openssl.x509.name").new()
    local _, err = name:add("CN", "example.com")
    
    for k, obj in pairs(name) do
      ngx.say(k, ":", require("cjson").encode(obj))
    end
    -- outputs 'CN: {"sn":"CN","id":"2.5.4.3","nid":13,"blob":"3.example.com","ln":"commonName"}'

resty.openssl.x509.altname

Module to interact with GENERAL_NAMES, an extension to X.509 names.

altname.new

syntax: altname, err = altname.new()

Creates an empty altname instance.

altname.dup

syntax: altname, err = altname.dup(altname_ptr_cdata)

Duplicates a STACK_OF(GENERAL_NAMES) to create a new altname instance. The function creates a new stack but won't duplicates elements in the stack.

altname.istype

syntax: altname = digest.istype(table)

Returns true if table is an instance of altname. Returns false otherwise.

altname:add

syntax: altname, err = altname:add(key, value)

Adds a name to altname stack, first argument is case-insensitive and can be one of

    RFC822Name
    RFC822
    Email
    UniformResourceIdentifier
    URI
    DNSName
    DNS
    IPAddress
    IP
    DirName

This function can be called multiple times in a chained fashion.

altname:tostring

syntax: txt = altname:tostring()

Outputs altname in a text representation.

    local altname, err = require("resty.openssl.x509.altname").new()
    
    _, err = altname
        :add("DNS", "2.example.com")
        :add("DnS", "3.example.com")
    
    ngx.say(altname:tostring())
    -- outputs "DNS=2.example.com/DNS=3.example.com"

altname:__metamethods

syntax: for k, obj in pairs(altname)

syntax: len = #altname

syntax: k, v = altname[i]

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with -DLUAJIT_ENABLE_LUA52COMPAT flag; otherwise use all, each, index and count instead.

See also "functions for stack-like objects".

resty.openssl.x509.extension

Module to interact with X.509 extensions.

extension.new

syntax: ext, err = extension.new(name, value, data?)

Creates a new extension instance. name and value are strings in OpenSSL arbitrary extension format.

data can be a table, string or nil. Where data is a table, the following key will be looked up:

    data = {
      issuer = resty.openssl.x509 instance,
      subject = resty.openssl.x509 instance,
      request = resty.openssl.x509.csr instance,
      crl = resty.openssl.x509.crl instance,
    }

When data is a string, it's the full nconf string. Using section lookup from value to data is also supported.

<details> <summary>Example usages:</summary>

    local extension = require("resty.openssl.x509.extension")
    -- extendedKeyUsage=serverAuth,clientAuth
    local ext, err = extension.new("extendedKeyUsage", "serverAuth,clientAuth")
    -- crlDistributionPoints=URI:http://myhost.com/myca.crl
    ext, err = extension.new("crlDistributionPoints", "URI:http://myhost.com/myca.crl")
    -- with section lookup
    ext, err = extension.new(
      "crlDistributionPoints", "crldp1_section",
      [[
      [crldp1_section]
      fullname=URI:http://myhost.com/myca.crl
      CRLissuer=dirName:issuer_sect
      reasons=keyCompromise, CACompromise
    
      [issuer_sect]
      C=UK
      O=Organisation
      CN=Some Name
      ]]
    )
    -- combine section lookup with other value
    ext, err = extension.new(
    "certificatePolicies", "ia5org,1.2.3.4,1.5.6.7.8,@polsect",
      [[
      [polsect]
      policyIdentifier = 1.3.5.8
      CPS.1="http://my.host.name/"
      CPS.2="http://my.your.name/"
      userNotice.1=@notice
    
      [notice]
      explicitText="Explicit Text Here"
      organization="Organisation Name"
      noticeNumbers=1,2,3,4
     ]]
    ))
    -- subjectKeyIdentifier=hash
    local x509, err = require("resty.openssl.x509").new()
    ext, err =  extension.new("subjectKeyIdentifier", "hash", {
        subject = x509
    })

</details>

See examples/tls-alpn-01.lua for an example to create extension with an unknown nid.

extension.dup

syntax: ext, err = extension.dup(extension_ptr_cdata)

Creates a new extension instance from X509_EXTENSION* pointer.

extension.from_der

syntax: ext, ok = extension.from_der(der, nid_or_txt, crit?)

Creates a new extension instance. der is the ASN.1 encoded string to be set for the extension.

nid_or_txt is a number or text representation of [NID] and crit is the critical flag of the extension.

See examples/tls-alpn-01.lua for an example to create extension with an unknown nid.

extension.from_data

syntax: ext, ok = extension.from_data(table, nid_or_txt, crit?)

Creates a new extension instance. table can be instance of:

• x509.altname

• x509.extension.info_access

• x509.extension.dist_points

nid_or_txt is a number or text representation of [NID] and crit is the critical flag of the extension.

extension.istype

syntax: ok = extension.istype(table)

Returns true if table is an instance of extension. Returns false otherwise.

extension:get_extension_critical

syntax: crit, err = extension:get_extension_critical()

Returns true if extension is critical. Returns false otherwise.

extension:set_extension_critical

syntax: ok, err = extension:set_extension_critical(crit)

Set the critical flag of the extension.

extension:get_object

syntax: obj = extension:get_object()

Returns the name of extension as ASN.1 Object. User can further use helper functions in resty.openssl.objects to print human readable texts.

extension:text

syntax: txt, err = extension:text()

Returns the text representation of extension

    local objects = require "resty.openssl.objects"
    ngx.say(cjson.encode(objects.obj2table(extension:get_object())))
    -- outputs '{"ln":"X509v3 Subject Key Identifier","nid":82,"sn":"subjectKeyIdentifier","id":"2.5.29.14"}'
    ngx.say(extension:text())
    -- outputs "C9:C2:53:61:66:9D:5F:AB:25:F4:26:CD:0F:38:9A:A8:49:EA:48:A9"

extension:tostring

syntax: txt, err = extension:tostring()

Same as extension:text.

resty.openssl.x509.extension.dist_points

Module to interact with CRL Distribution Points(DIST_POINT stack).

dist_points.new

syntax: dp, err = dist_points.new()

Creates a new dist_points instance.

dist_points.dup

syntax: dp, err = dist_points.dup(dist_points_ptr_cdata)

Duplicates a STACK_OF(DIST_POINT) to create a new dist_points instance. The function creates a new stack but won't duplicates elements in the stack.

dist_points.istype

syntax: ok = dist_points.istype(table)

Returns true if table is an instance of dist_points. Returns false otherwise.

dist_points:__metamethods

syntax: for i, obj in ipairs(dist_points)

syntax: len = #dist_points

syntax: obj = dist_points[i]

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with -DLUAJIT_ENABLE_LUA52COMPAT flag; otherwise use all, each, index and count instead.

See also "functions for stack-like objects".

Each object returned when iterrating dist_points instance is a x509.altname instance.

    local x = x509.new(io.open("/path/to/a_cert_has_dist_points.crt"):read("*a"))
    
    local cdp = x:get_crl_distribution_points()
    
    local an = cdp[1]
    ngx.say(an:tostring())
    -- or any other function for resty.openssl.x509.altname
    
    for _, an in ipairs(cdp) do
      ngx.say(an:tostring())
    end

resty.openssl.x509.extension.info_access

Module to interact with Authority Information Access data (AUTHORITY_INFO_ACCESS, ACCESS_DESCRIPTION stack).

info_access.new

syntax: aia, err = info_access.new()

Creates a new info_access instance.

info_access.dup

syntax: aia, err = info_access.dup(info_access_ptr_cdata)

Duplicates a AUTHORITY_INFO_ACCESS to create a new info_access instance. The function creates a new stack but won't duplicates elements in the stack.

info_access.istype

syntax: ok = info_access.istype(table)

Returns true if table is an instance of info_access. Returns false otherwise.

info_access:add

syntax: ok, err = info_access:add(x509)

Add a x509 object to the info_access. The first argument must be a resty.openssl.x509 instance.

info_access:__metamethods

syntax: for i, obj in ipairs(info_access)

syntax: len = #info_access

syntax: obj = info_access[i]

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with -DLUAJIT_ENABLE_LUA52COMPAT flag; otherwise use all, each, index and count instead.

See also "functions for stack-like objects".

Each object returned when iterrating dist_points instance is a table of [NID] type and values.

    local cjson = require("cjosn")
    local x509 = require("resty.openssl.x509")
    local crt = x509.new(io.open("/path/to/a_cert_has_info_access.crt"):read("*a"))
    
    local aia = crt:get_info_access()
    
    ngx.say(cjson.encode(aia[1]))
    -- outputs '[178,"URI","http:\/\/ocsp.starfieldtech.com\/"]'
    
    for _, a in ipairs(aia) do
      ngx.say(cjson.encode(a))
    end

resty.openssl.x509.extensions

Module to interact with X.509 Extension stack.

extensions.new

syntax: ch, err = extensions.new()

Creates a new extensions instance.

extensions.dup

syntax: ch, err = extensions.dup(extensions_ptr_cdata)

Duplicates a STACK_OF(X509_EXTENSION) to create a new extensions instance. The function creates a new stack but won't duplicates elements in the stack.

extensions.istype

syntax: ok = extensions.istype(table)

Returns true if table is an instance of extensions. Returns false otherwise.

extensions:add

syntax: ok, err = extensions:add(x509)

Add a x509 object to the extensions. The first argument must be a resty.openssl.x509 instance.

extensions:__metamethods

syntax: for i, obj in ipairs(extensions)

syntax: len = #extensions

syntax: obj = extensions[i]

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with -DLUAJIT_ENABLE_LUA52COMPAT flag; otherwise use all, each, index and count instead.

See also "functions for stack-like objects".

resty.openssl.x509.chain

Module to interact with X.509 stack.

chain.new

syntax: ch, err = chain.new()

Creates a new chain instance.

chain.dup

syntax: ch, err = chain.dup(chain_ptr_cdata)

Duplicates a STACK_OF(X509) to create a new chain instance. The function creates a new stack and increases reference count for all elements by 1. But it won't duplicate the elements themselves.

chain.istype

syntax: ok = chain.istype(table)

Returns true if table is an instance of chain. Returns false otherwise.

chain:add

syntax: ok, err = chain:add(x509)

Add a x509 object to the chain. The first argument must be a resty.openssl.x509 instance.

chain:__metamethods

syntax: for i, obj in ipairs(chain)

syntax: len = #chain

syntax: obj = chain[i]

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with -DLUAJIT_ENABLE_LUA52COMPAT flag; otherwise use all, each, index and count instead.

See also "functions for stack-like objects".

resty.openssl.x509.store

Module to interact with X.509 certificate store (X509_STORE).

store.new

syntax: st, err = store.new()

Creates a new store instance.

store.istype

syntax: ok = store.istype(table)

Returns true if table is an instance of store. Returns false otherwise.

store:use_default

syntax: ok, err = store:use_default()

Loads certificates into the X509_STORE from the hardcoded default paths.

Note that to load "default" CAs correctly, usually you need to install a CA certificates bundle. For example, the package in Debian/Ubuntu is called ca-certificates.

store:add

syntax: ok, err = store:add(x509_or_crl)

Adds a X.509 or a CRL object into store. The argument must be a resty.openssl.x509 instance or a resty.openssl.x509.store instance.

store:load_file

syntax: ok, err = store:load_file(path)

Loads a X.509 certificate on file system into store.

store:load_directory

syntax: ok, err = store:load_directory(path)

Loads a directory of X.509 certificates on file system into store. The certificates in the directory must be in hashed form, as documented in X509_LOOKUP_hash_dir(3).

store:verify

syntax: chain, err = store:verify(x509, chain?, return_chain?)

Verifies a X.509 object with the store. The first argument must be resty.openssl.x509 instance. Optionally accept a validation chain as second argument, which must be a resty.openssl.x509.chain instance.

If verification succeed, and return_chain is set to true, returns the proof of validation as a resty.openssl.x509.chain; otherwise returns true only. If verification failed, returns nil and error explaining the reason.

resty.openssl.x509.revoked

Module to interact with X509_REVOKED.

revoked.new

syntax: ch, err = revoked.new(serial_number, time, reason)

Creates a new revoked instance. serial_number can be either a resty.openssl.bn instance or a number. time and reason must be numbers.

revoked.istype

syntax: ok = revoked.istype(table)

Returns true if table is an instance of revoked. Returns false otherwise.

Functions for stack-like objects

metamethods

syntax: for k, obj in pairs(x)

syntax: for k, obj in ipairs(x)

syntax: len = #x

syntax: obj = x[i]

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with -DLUAJIT_ENABLE_LUA52COMPAT flag.

Each object may only support either pairs or ipairs. Index is 1-based.

    local name, err = require("resty.openssl.x509.name").new()
    local _, err = name:add("CN", "example.com")
    
    for k, obj in pairs(name) do
      ngx.say(k, ":", require("cjson").encode(obj))
    end
    -- outputs 'CN: {"sn":"CN","id":"2.5.4.3","nid":13,"blob":"3.example.com","ln":"commonName"}'

each

syntax: iter = x:each()

Return an iterator to traverse objects. Use this while LUAJIT_ENABLE_LUA52COMPAT is not enabled.

    local name, err = require("resty.openssl.x509.name").new()
    local _, err = name:add("CN", "example.com")
    
    local iter = name:each()
    while true do
      local k, obj = iter()
      if not k then
        break
      end
    end

all

syntax: objs, err = x:all()

Returns all objects in the table. Use this while LUAJIT_ENABLE_LUA52COMPAT is not enabled.

count

syntax: len = x:count()

Returns count of objects of the table. Use this while LUAJIT_ENABLE_LUA52COMPAT is not enabled.

index

syntax: obj = x:index(i)

Returns objects at index of i of the table, index is 1-based. If index is out of bound, nil is returned.

General rules on garbage collection

• When a type is added or returned to another type, it's internal cdata is always copied.

      local name = require("resty.openssl.x509.name"):add("CN", "example.com")
      local x509 = require("resty.openssl.x509").new()
      -- `name` is copied when added to x509
      x509:set_subject_name(name)
      
      name:add("L", "Mars")
      -- subject_name in x509 will not be modified

• The creator set the GC handler; the user must not free it.

• For a stack:

• If it's created by new(): set GC handler to sk_TYPE_pop_free

# lua-resty-openssl

FFI-based OpenSSL binding for LuaJIT, supporting OpenSSL 3.0, 1.1 and 1.0.2 series

  

Table of Contents =================

- [Description](#description) - [Status](#status) - [Synopsis](#synopsis) * [resty.openssl](#restyopenssl) + [openssl.luaossl_compat](#opensslluaossl_compat) + [openssl.resty_hmac_compat](#opensslresty_hmac_compat) * [resty.openssl.version](#restyopensslversion) + [version_num](#version_num) + [version_text](#version_text) + [version.version](#versionversion) + [version.info](#versioninfo) + [OPENSSL_30](#openssl_30) + [OPENSSL_11](#openssl_11) + [OPENSSL_10](#openssl_10) * [resty.openssl.pkey](#restyopensslpkey) + [pkey.new](#pkeynew) + [pkey.istype](#pkeyistype) + [pkey.paramgen](#pkeyparamgen) + [pkey:get_parameters](#pkeyget_parameters) + [pkey:set_parameters](#pkeyset_parameters) + [pkey:get_key_type](#pkeyget_key_type) + [pkey:sign](#pkeysign) + [pkey:verify](#pkeyverify) + [pkey:encrypt](#pkeyencrypt) + [pkey:decrypt](#pkeydecrypt) + [pkey:sign_raw](#pkeysign_raw) + [pkey:verify_recover](#pkeyverify_recover) + [pkey:derive](#pkeyderive) + [pkey:tostring](#pkeytostring) + [pkey:to_PEM](#pkeyto_pem) * [resty.openssl.bn](#restyopensslbn) + [bn.new](#bnnew) + [bn.dup](#bndup) + [bn.istype](#bnistype) + [bn.from_binary, bn:to_binary](#bnfrom_binary-bnto_binary) + [bn.from_hex, bn:to_hex](#bnfrom_hex-bnto_hex) + [bn.from_dec, bn:to_dec](#bnfrom_dec-bnto_dec) + [bn:to_number](#bnto_number) + [bn:__metamethods](#bn__metamethods) + [bn:add, bn:sub, bn:mul, bn:div, bn:exp, bn:mod, bn:gcd](#bnadd-bnsub-bnmul-bndiv-bnexp-bnmod-bngcd) + [bn:sqr](#bnsqr) + [bn:mod_add, bn:mod_sub, bn:mod_mul, bn:mod_exp](#bnmod_add-bnmod_sub-bnmod_mul-bnmod_exp) + [bn:mod_sqr](#bnmod_sqr) + [bn:lshift, bn:rshift](#bnlshift-bnrshift) + [bn:is_zero, bn:is_one, bn:is_odd, bn:is_word](#bnis_zero-bnis_one-bnis_odd-bnis_word) + [bn:is_prime](#bnis_prime) * [resty.openssl.cipher](#restyopensslcipher) + [cipher.new](#ciphernew) + [cipher.istype](#cipheristype) + [cipher:encrypt](#cipherencrypt) + [cipher:decrypt](#cipherdecrypt) + [cipher:init](#cipherinit) + [cipher:update](#cipherupdate) + [cipher:update_aead_aad](#cipherupdate_aead_aad) + [cipher:get_aead_tag](#cipherget_aead_tag) + [cipher:set_aead_tag](#cipherset_aead_tag) + [cipher:final](#cipherfinal) + [cipher:derive](#cipherderive) * [resty.openssl.digest](#restyopenssldigest) + [digest.new](#digestnew) + [digest.istype](#digestistype) + [digest:update](#digestupdate) + [digest:final](#digestfinal) + [digest:reset](#digestreset) * [resty.openssl.hmac](#restyopensslhmac) + [hmac.new](#hmacnew) + [hmac.istype](#hmacistype) + [hmac:update](#hmacupdate) + [hmac:final](#hmacfinal) + [hmac:reset](#hmacreset) * [resty.openssl.kdf](#restyopensslkdf) + [kdf.derive](#kdfderive) * [resty.openssl.objects](#restyopensslobjects) + [objects.obj2table](#objectsobj2table) + [objects.nid2table](#objectsnid2table) + [objects.txt2nid](#objectstxt2nid) * [resty.openssl.rand](#restyopensslrand) + [rand.bytes](#randbytes) * [resty.openssl.x509](#restyopensslx509) + [x509.new](#x509new) + [x509.dup](#x509dup) + [x509.istype](#x509istype) + [x509:digest](#x509digest) + [x509:pubkey_digest](#x509pubkey_digest) + [x509:get_*, x509:set_*](#x509get_-x509set_) + [x509:get_lifetime](#x509get_lifetime) + [x509:set_lifetime](#x509set_lifetime) + [x509:get_extension](#x509get_extension) + [x509:add_extension](#x509add_extension) + [x509:set_extension](#x509set_extension) + [x509:get_extension_critical](#x509get_extension_critical) + [x509:set_extension_critical](#x509set_extension_critical) + [x509:get_ocsp_url](#x509get_ocsp_url) + [x509:get_crl_url](#x509get_crl_url) + [x509:sign](#x509sign) + [x509:verify](#x509verify) + [x509:tostring](#x509tostring) + [x509:to_PEM](#x509to_pem) * [resty.openssl.x509.csr](#restyopensslx509csr) + [csr.new](#csrnew) + [csr.istype](#csristype) + [csr:get_*, csr:set_*](#csrget_-csrset_) + [csr:get_extension](#csrget_extension) + [csr:add_extension](#csradd_extension) + [csr:set_extension](#csrset_extension) + [csr:get_extension_critical](#csrget_extension_critical) + [csr:set_extension_critical](#csrset_extension_critical) + [csr:sign](#csrsign) + [csr:verify](#csrverify) + [csr:tostring](#csrtostring) + [csr:to_PEM](#csrto_pem) * [resty.openssl.x509.crl](#restyopensslx509crl) + [crl.new](#crlnew) + [crl.istype](#crlistype) + [crl:get_*, crl:set_*](#crlget_-crlset_) + [crl:get_extension](#crlget_extension) + [crl:add_extension](#crladd_extension) + [crl:set_extension](#crlset_extension) + [crl:get_extension_critical](#crlget_extension_critical) + [crl:set_extension_critical](#crlset_extension_critical) + [crl:add_revoked](#crladd_revoked) + [crl:sign](#crlsign) + [crl:verify](#crlverify) + [crl:tostring](#crltostring) + [crl:to_PEM](#crlto_pem) * [resty.openssl.x509.name](#restyopensslx509name) + [name.new](#namenew) + [name.dup](#namedup) + [name.istype](#nameistype) + [name:add](#nameadd) + [name:find](#namefind) + [name:tostring](#nametostring) + [name:__metamethods](#name__metamethods) * [resty.openssl.x509.altname](#restyopensslx509altname) + [altname.new](#altnamenew) + [altname.dup](#altnamedup) + [altname.istype](#altnameistype) + [altname:add](#altnameadd) + [altname:tostring](#altnametostring) + [altname:__metamethods](#altname__metamethods) * [resty.openssl.x509.extension](#restyopensslx509extension) + [extension.new](#extensionnew) + [extension.dup](#extensiondup) + [extension.from_data](#extensionfrom_data) + [extension.istype](#extensionistype) + [extension:get_extension_critical](#extensionget_extension_critical) + [extension:set_extension_critical](#extensionset_extension_critical) + [extension:get_object](#extensionget_object) + [extension:text](#extensiontext) * [resty.openssl.x509.extension.dist_points](#restyopensslx509extensiondist_points) + [dist_points.new](#dist_pointsnew) + [dist_points.dup](#dist_pointsdup) + [dist_points.istype](#dist_pointsistype) + [dist_points:__metamethods](#dist_points__metamethods) * [resty.openssl.x509.extension.info_access](#restyopensslx509extensioninfo_access) + [info_access.new](#info_accessnew) + [info_access.dup](#info_accessdup) + [info_access.istype](#info_accessistype) + [info_access:add](#info_accessadd) + [info_access:__metamethods](#info_access__metamethods) * [resty.openssl.x509.extensions](#restyopensslx509extensions) + [extensions.new](#extensionsnew) + [extensions.dup](#extensionsdup) + [extensions.istype](#extensionsistype) + [extensions:add](#extensionsadd) + [extensions:__metamethods](#extensions__metamethods) * [resty.openssl.x509.chain](#restyopensslx509chain) + [chain.new](#chainnew) + [chain.dup](#chaindup) + [chain.istype](#chainistype) + [chain:add](#chainadd) + [chain:__metamethods](#chain__metamethods) * [resty.openssl.x509.store](#restyopensslx509store) + [store.new](#storenew) + [store.istype](#storeistype) + [store:use_default](#storeuse_default) + [store:add](#storeadd) + [store:load_file](#storeload_file) + [store:load_directory](#storeload_directory) + [store:verify](#storeverify) * [resty.openssl.x509.revoked](#restyopensslx509revoked) + [revoked.new](#revokednew) + [revoked.istype](#revokedistype) * [Functions for stack-like objects](#functions-for-stack-like-objects) + [metamethods](#metamethods) + [each](#each) + [all](#all) + [count](#count) + [index](#index) - [General rules on garbage collection](#general-rules-on-garbage-collection) - [Code generation](#code-generation) - [Compatibility](#compatibility) - [Credits](#credits) - [Copyright and License](#copyright-and-license) - [See Also](#see-also)

Description ===========

`lua-resty-openssl` is a FFI-based OpenSSL binding library, currently supports OpenSSL `3.0.0`, `1.1.1`, `1.1.0` and `1.0.2` series.

**Note: when using with OpenSSL 1.0.2, it's recommanded to not use this library with other FFI-based OpenSSL binding libraries to avoid potential mismatch of `cdef`.**

[Back to TOC](#table-of-contents)

Status ========

Production.

Synopsis ========

This library is greatly inspired by [luaossl](https://github.com/wahern/luaossl), while uses the naming conversion closer to original OpenSSL API. For example, a function called `X509_set_pubkey` in OpenSSL C API will expect to exist as `resty.openssl.x509:set_pubkey`. *CamelCase*s are replaced to *underscore_case*s, for exmaple `X509_set_serialNumber` becomes `resty.openssl.x509:set_serial_number`. Another difference than `luaossl` is that errors are never thrown using `error()` but instead return as last parameter.

Each Lua table returned by `new()` contains a cdata object `ctx`. User are not supposed to manully setting `ffi.gc` or calling corresponding destructor of the `ctx` struct (like `*_free` functions).

[Back to TOC](#table-of-contents)

## resty.openssl

This meta module provides a version sanity check against linked OpenSSL library and returns all exported modules to a table.

```lua return { _VERSION = 'x.y.z', bn = require("resty.openssl.bn"), cipher = require("resty.openssl.cipher"), digest = require("resty.openssl.digest"), hmac = require("resty.openssl.hmac"), kdf = require("resty.openssl.kdf"), pkey = require("resty.openssl.pkey"), objects = require("resty.openssl.objects"), rand = require("resty.openssl.rand"), version = require("resty.openssl.version"), x509 = require("resty.openssl.x509"), altname = require("resty.openssl.x509.altname"), chain = require("resty.openssl.x509.chain"), csr = require("resty.openssl.x509.csr"), crl = require("resty.openssl.x509.crl"), extension = require("resty.openssl.x509.extension"), extensions = require("resty.openssl.x509.extensions"), name = require("resty.openssl.x509.name"), store = require("resty.openssl.x509.store"), } ```

Starting OpenSSL 3.0, [`provider`](#restyopensslprovider) is also available.

[Back to TOC](#table-of-contents)

### openssl.luaossl_compat

**syntax**: *openssl.luaossl_compat()*

Provides `luaossl` flavored API which uses *camelCase* naming; user can expect drop in replacement.

For example, `pkey:get_parameters` is mapped to `pkey:getParameters`.

Note that not all `luaossl` API has been implemented, please check readme for source of truth.

[Back to TOC](#table-of-contents)

### openssl.resty_hmac_compat

**syntax**: *openssl.resty_hmac_compat()*

Call this function before `require("resty.hmac")` to allow these two libraries play nice with each other. This function is not available with OpenSSL 1.0.

[Back to TOC](#table-of-contents)

## resty.openssl.version

A module to provide version info.

[Back to TOC](#table-of-contents)

### version_num

The OpenSSL version number.

[Back to TOC](#table-of-contents)

### version_text

The OpenSSL version text.

[Back to TOC](#table-of-contents)

### version.version

**syntax**: *text = version.version(types)*

Returns various OpenSSL version information. Available values for `types` are:

    VERSION
    CFLAGS
    BUILT_ON
    PLATFORM
    DIR
    ENGINES_DIR
    VERSION_STRING
    FULL_VERSION_STRING
    MODULES_DIR
    CPU_INFO

For OpenSSL prior to 1.1.x, only `VERSION`, `CFLAGS`, `BUILT_ON`, `PLATFORM` and `DIR` are supported. Please refer to [OPENSSL_VERSION_NUMBER(3)](https://www.openssl.org/docs/manmaster/man3/OPENSSL_VERSION_NUMBER.html) for explanation of each type.

```lua local version = require("resty.openssl.version") ngx.say(string.format("%x", version.version_num)) -- outputs "101000bf" ngx.say(version.version_text) -- outputs "OpenSSL 1.1.0k 28 May 2019" ngx.say(version.version(version.PLATFORM)) -- outputs "darwin64-x86_64-cc" ```

[Back to TOC](#table-of-contents)

### version.info

**syntax**: *text = version.info(types)*

Returns various OpenSSL information. Available values for `types` are:

    INFO_ENGINES_DIR
    INFO_DSO_EXTENSION
    INFO_CPU_SETTINGS
    INFO_LIST_SEPARATOR
    INFO_DIR_FILENAME_SEPARATOR
    INFO_CONFIG_DIR
    INFO_SEED_SOURCE
    INFO_MODULES_DIR

This function is only available on OpenSSL 3.0. Please refer to [OPENSSL_VERSION_NUMBER(3)](https://www.openssl.org/docs/manmaster/man3/OPENSSL_VERSION_NUMBER.html) for explanation of each type.

```lua local version = require("resty.openssl.version") ngx.say(version.version(version.INFO_DSO_EXTENSION)) -- outputs ".so" ```

[Back to TOC](#table-of-contents)

### OPENSSL_30

A boolean indicates whether the linked OpenSSL is 3.0 series.

[Back to TOC](#table-of-contents)

### OPENSSL_11

A boolean indicates whether the linked OpenSSL is 1.1 series.

[Back to TOC](#table-of-contents)

### OPENSSL_10

A boolean indicates whether the linked OpenSSL is 1.0 series.

[Back to TOC](#table-of-contents)

## resty.openssl.pkey

Module to interact with private keys and public keys (EVP_PKEY).

Each key type may only support part of operations:

Key Type | Load existing key | Key generation | Encrypt/Decrypt | Sign/Verify | Key Exchange | ---------|----------|----------------|-----------------|-------------|---------- | RSA| Y | Y | Y | Y | | DH | Y | Y | | | Y | EC | Y | Y | | Y (ECDSA) | Y (ECDH) | Ed25519 | Y | Y | | Y (PureEdDSA) | | X25519 | Y | Y | | | Y (ECDH) | Ed448 | Y | Y | | Y (PureEdDSA) | | X448 | Y | Y | | | Y (ECDH) |

`Ed25519`, `X25519`, `Ed448` and `X448` keys are only supported since OpenSSL 1.1.0.

[Back to TOC](#table-of-contents)

### pkey.new

**syntax**: *pk, err = pkey.new(config)*

**syntax**: *pk, err = pkey.new(string, opts?)*

**syntax**: *pk, err = pkey.new()*

Function to generate a key pair, or load existing key in PEM or DER format.

1. Pass a `config` table to create a new PKEY pair. Which defaults to:

```lua locak key, err = pkey.new({ type = 'RSA', bits = 2048, exp = 65537 }) ```

To generate EC or DH key, please refer to [pkey.paramgen](#pkeyparamgen) for possible values of `config` table. It's also possible to load a PEM-encoded EC or DH parameters for key generation:

```lua local dhparam = pkey.paramgen({ type = 'DH', group = 'dh_1024_160' }) -- OR -- local dhparam = io.read("dhparams.pem"):read("*a")

local key, err = pkey.new({ type = 'DH', param = dhparam, }) ```

Other possible `type`s are `Ed25519`, `X25519`, `Ed448` and `X448`. No additional parameters can be set during key generation for those keys.

2. Pass a `string` of private or public key in PEM, DER or JWK format text; optionally accpet a table `opts` to explictly load `format` and key `type`. When loading a key in PEM format, `passphrase` or `passphrase_cb` may be provided to decrypt the key.

```lua pkey.new(pem_or_der_text, { format = "*", -- choice of "PEM", "DER", "JWK" or "*" for auto detect type = "*", -- choice of "pr" for privatekey, "pu" for public key and "*" for auto detect passphrase = "secret password", -- the PEM encryption passphrase passphrase_cb = function() return "secret password" end, -- the PEM encryption passphrase callback function }

```

  -  When loading JWK, make sure the encoded JSON text is passed in.
  - Currently it's not supported to contraint
  `type` on JWK key, the parameters in provided JSON will decide if a private or public key is loaded.
  - Only JWK with key type of `RSA`, `P-256`, `P-384` and `P-512` `EC`,
  `Ed25519`, `X25519`, `Ed448` and `X448` `OKP` keys are supported.
  - Public key part for `OKP` keys
  (the `x` parameter) is always not honored and derived from private key part (the `d` parameter) if it's specified.

3. Pass `nil` to create a 2048 bits RSA key. 4. Pass a `EVP_PKEY*` pointer, to return a wrapped `pkey` instance. Normally user won't use this approach. User shouldn't free the pointer on their own, since the pointer is not copied.

[Back to TOC](#table-of-contents)

### pkey.istype

**syntax**: *ok = pkey.istype(table)*

Returns `true` if table is an instance of `pkey`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### pkey.paramgen

**syntax**: *pem_txt, err = pk.paramgen(config)*

Generate parameters for EC or DH key and output as PEM-encoded text.

For EC key:

 Parameter | Description
-----------|-------------
type | `"EC"`
curve | EC curves. If omitted, default to `"prime192v1"`. To see list of supported EC curves, use `openssl ecparam -list_curves`.

For DH key:

 Parameter | Description
-----------|-------------
type | `"DH"`
bits | Generate a new DH parameter with `bits` long prime. If omitted, default to `2048`. Starting OpenSSL 3.0, only bits equal to 2048 is allowed.
group | Use predefined groups instead of generating new one. `bit` will be ignored if `group` is set.

Possible values for `group` are: - [RFC7919](https://tools.ietf.org/html/rfc7919#appendix-A.1) `"ffdhe2048"`, `"ffdhe3072"`, `"ffdhe4096"`, `"ffdhe6144"`, `"ffdhe8192"` - [RFC5114](https://tools.ietf.org/html/rfc5114#section-2) `"dh_1024_160"`, `"dh_2048_224"`, `"dh_2048_256"` - [RFC3526](https://tools.ietf.org/html/rfc3526#page-3) `"modp_1536"`, `"modp_2048"`, `"modp_3072"`, `"modp_4096"`, `"modp_6144"`, `"modp_8192"`

```lua local pem, err = pkey.paramgen({ type = 'EC', curve = 'prime192v1', })

local pem, err = pkey.paramgen({ type = 'DH', group = 'ffdhe4096', }) ```

[Back to TOC](#table-of-contents)

### pkey:get_parameters

**syntax**: *parameters, err = pk:get_parameters()*

Returns a table containing the `parameters` of pkey instance.

[Back to TOC](#table-of-contents)

### pkey:set_parameters

**syntax**: *ok, err = pk:set_parameters(params)*

Set the parameters of the pkey from a table `params`. If the parameter is not set in the `params` table, it remains untouched in the pkey instance.

```lua local pk, err = require("resty.openssl.pkey").new() local parameters, err = pk:get_parameters() local e = parameters.e ngx.say(e:to_number()) -- outputs 65537

local ok, err = pk:set_parameters({ e = require("resty.openssl.bn").from_hex("100001") })

local ok, err = pk:set_parameters(parameters) ```

Parameters for RSA key:

 Parameter | Description | Type
-----------|-------------|------
n | modulus common to both public and private key | [bn](#restyopensslbn)
e | public exponent | [bn](#restyopensslbn)
d | private exponent | [bn](#restyopensslbn)
p | first factor of **n** | [bn](#restyopensslbn)
q | second factor of **n** | [bn](#restyopensslbn)
dmp1 | `d mod (p - 1)`, exponent1 | [bn](#restyopensslbn)
dmq1 | `d mod (q - 1)`, exponent2 | [bn](#restyopensslbn)
iqmp | `(InverseQ)(q) = 1 mod p`, coefficient | [bn](#restyopensslbn)

Parameters for EC key:

 Parameter | Description | Type
-----------|-------------|-----
private | private key | [bn](#restyopensslbn)
public | public key | [bn](#restyopensslbn)
x | x coordinate of the public key| [bn](#restyopensslbn)
y | y coordinate of the public key| [bn](#restyopensslbn)
group | the named curve group | [NID] as a number, when passed in as `set_parameters()`, it's also possible to use the text representation. This is different from `luaossl` where a `EC_GROUP` instance is returned.

It's not possible to set `x`, `y` with `public` at same time as `x` and `y` is basically another representation of `public`. Also currently it's only possible to set `x` and `y` at same time.

Parameters for DH key:

 Parameter | Description | Type
-----------|-------------|-----
private | private key | [bn](#restyopensslbn)
public | public key | [bn](#restyopensslbn)
p | prime modulus | [bn](#restyopensslbn)
q | reference position | [bn](#restyopensslbn)
p | base generator | [bn](#restyopensslbn)

Parameters for Curve25519 and Curve448 keys:

 Parameter | Description | Type
-----------|-------------|-----
private | raw private key represented as bytes | string
public | raw public key represented as bytes | string

[Back to TOC](#table-of-contents)

### pkey:get_key_type

**syntax**: *obj, err = pk:get_key_type()*

Returns a ASN1_OBJECT of key type of the private key as a table.

```lua local pkey, err = require("resty.openssl.pkey").new({type="X448"})

ngx.say(require("cjson").encode(pkey:get_key_type())) -- outputs '{"ln":"X448","nid":1035,"sn":"X448","id":"1.3.101.111"}' ```

[Back to TOC](#table-of-contents)

### pkey:sign

**syntax**: *signature, err = pk:sign(digest)*

Perform a digest signing using the private key defined in `pkey` instance. The `digest` parameter must be a [resty.openssl.digest](#restyopenssldigest) instance or a string. Returns the signed text and error if any.

When passing a [digest](#restyopenssldigest) instance as `digest` parameter, it should not have been called [final()](#digestfinal), user should only use [update()](#digestupdate).

For RSA and EC keys, passing a string as `digest` parameter does the SHA256 as digest method by default. For Ed25519 or Ed448 keys, this function does a PureEdDSA verification and requires `digest` to be the string that needs signing. No message digest is used for Ed keys.

For EC key, this function does a ECDSA signing.

Note that OpenSSL does not support EC digital signature (ECDSA) with the obsolete MD5 hash algorithm and will return error on this combination. See [EVP_DigestSign(3)](https://www.openssl.org/docs/manmaster/man3/EVP_DigestSign.html) for a list of algorithms and associated public key algorithms.

```lua -- RSA and EC keys local pk, err = require("resty.openssl.pkey").new() local digest, err = require("resty.openssl.digest").new("SHA256") digest:update("dog") -- WRONG: -- digest:final("dog") local signature, err = pk:sign(digest) -- uses SHA256 by default local signature, err = pk:sign("dog") ngx.say(ngx.encode_base64(signature))

-- Ed25519 and Ed448 keys local pk, err = require("resty.openssl.pkey").new({ type = "Ed25519", }) local signature, err = pk:sign("23333") ngx.say(ngx.encode_base64(signature)) ```

[Back to TOC](#table-of-contents)

### pkey:verify

**syntax**: *ok, err = pk:verify(signature, digest)*

Verify a signture (which can be the string returned by [pkey:sign](#pkey-sign)). The second argument must be a [resty.openssl.digest](#restyopenssldigest) instance that uses the same digest algorithm as used in `sign` or a string. `ok` returns `true` if verficiation is successful and `false` otherwise. Note when verfication failed `err` will not be set. For EC key, this function does a ECDSA verification.

For RSA and EC keys, passing a string as `digest` parameter uses the SHA256 as digest method by default. For Ed25519 or Ed448 keys, this function does a PureEdDSA verification and requires both `signature` and `digest` to be string. No message digest is used for Ed keys.

```lua -- RSA and EC keys local pk, err = require("resty.openssl.pkey").new() local digest, err = require("resty.openssl.digest").new("SHA256") digest:update("dog") -- WRONG: -- digest:final("dog") local signature, err = pk:sign(digest) -- uses SHA256 by default local signature, err = pk:sign("dog") ngx.say(ngx.encode_base64(signature))

digest, err = require("resty.openssl.digest").new("SHA256") digest:update("dog") local ok, err = pk:verify(signature, digest) -- uses SHA256 by default local ok, err = pk:verify(signature, "dog")

-- Ed25519 and Ed448 keys local pk, err = require("resty.openssl.pkey").new({ type = "Ed25519", }) local signature, err = pk:sign("23333") ngx.say(ngx.encode_base64(signature))

```

[Back to TOC](#table-of-contents)

### pkey:encrypt

**syntax**: *cipher_txt, err = pk:encrypt(txt, padding?)*

Encrypts plain text `txt` with `pkey` instance, which must loaded a public key.

When key is a RSA key, the function accepts an optional second argument `padding` which can be:

```lua pkey.PADDINGS = { RSA_PKCS1_PADDING = 1, RSA_SSLV23_PADDING = 2, RSA_NO_PADDING = 3, RSA_PKCS1_OAEP_PADDING = 4, RSA_X931_PADDING = 5, RSA_PKCS1_PSS_PADDING = 6, } ```

If omitted, `padding` is default to `pkey.PADDINGS.RSA_PKCS1_PADDING`.

[Back to TOC](#table-of-contents)

### pkey:decrypt

**syntax**: *txt, err = pk:decrypt(cipher_txt, padding?)*

Decrypts cipher text `cipher_txt` with pkey instance, which must loaded a private key.

The optional second argument `padding` has same meaning in [pkey:encrypt](#pkeyencrypt).

```lua local pkey = require("resty.openssl.pkey") local privkey, err = pkey.new() local pub_pem = privkey:to_PEM("public") local pubkey, err = pkey.new(pub_pem) local s, err = pubkey:encrypt("🦢", pkey.PADDINGS.RSA_PKCS1_PADDING) ngx.say(#s) -- outputs 256 local decrypted, err = privkey:decrypt(s) ngx.say(decrypted) -- outputs "🦢" ```

[Back to TOC](#table-of-contents)

### pkey:sign_raw

**syntax**: *signature, err = pk:sign_raw(txt, padding?)*

Signs the cipher text `cipher_txt` with pkey instance, which must loaded a private key.

The optional second argument `padding` has same meaning in [pkey:encrypt](#pkeyencrypt).

This function may also be called "private encrypt" in some implementations like NodeJS or PHP. Do note as the function names suggested, this function is not secure to be regarded as an encryption. When developing new applications, user should use [pkey:sign](#pkeysign) for signing with digest, or [pkey:encrypt](#pkeyencrypt) for encryption.

See [examples/raw-sign-and-recover.lua](https://github.com/fffonion/lua-resty-openssl/blob/master/examples/raw-sign-and-recover.lua) for an example.

[Back to TOC](#table-of-contents)

### pkey:verify_recover

**syntax**: *txt, err = pk:verify_recover(signature, padding?)*

Verify the cipher text `signature` with pkey instance, which must loaded a public key, and also returns the original text being signed. This operation is only supported by RSA key.

The optional second argument `padding` has same meaning in [pkey:encrypt](#pkeyencrypt).

This function may also be called "public decrypt" in some implementations like NodeJS or PHP.

See [examples/raw-sign-and-recover.lua](https://github.com/fffonion/lua-resty-openssl/blob/master/examples/raw-sign-and-recover.lua) for an example.

[Back to TOC](#table-of-contents)

### pkey:derive

**syntax**: *txt, err = pk:derive(peer_key)*

Derive public key algorithm shared secret `peer_key`, which must be a [pkey](#restyopensslpkey) instance.

See [examples/x25519-dh.lua](https://github.com/fffonion/lua-resty-openssl/blob/master/examples/x25519-dh.lua) for an example on how key exchange works for X25519 keys with DH algorithm.

[Back to TOC](#table-of-contents)

### pkey:tostring

**syntax**: *txt, err = pk:tostring(private_or_public?, fmt?)*

Outputs private key or public key of pkey instance in PEM-formatted text. The first argument must be a choice of `public`, `PublicKey`, `private`, `PrivateKey` or nil. The second argument `fmt` can be `PEM`, `DER`, `JWK` or nil. If both arguments are omitted, this functions returns the `PEM` representation of public key.

[Back to TOC](#table-of-contents)

### pkey:to_PEM

**syntax**: *pem, err = pk:to_PEM(private_or_public?)*

Equivalent to `pk:tostring(private_or_public, "PEM")`.

[Back to TOC](#table-of-contents)

## resty.openssl.bn

Module to expose BIGNUM structure. Note bignum is a big integer, no float operations (like square root) are supported.

[Back to TOC](#table-of-contents)

### bn.new

**syntax**: *b, err = bn.new(number?)*

Creates a `bn` instance. The first argument can be a Lua number or `nil` to creates an empty instance.

[Back to TOC](#table-of-contents)

### bn.dup

**syntax**: *b, err = bn.dup(bn_ptr_cdata)*

Duplicates a `BIGNUM*` to create a new `bn` instance.

[Back to TOC](#table-of-contents)

### bn.istype

**syntax**: *ok = bn.istype(table)*

Returns `true` if table is an instance of `bn`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### bn.from_binary, bn:to_binary

**syntax**: *bn, err = bn.from_binary(bin)*

**syntax**: *bin, err = bn:to_binary()*

Creates a `bn` instance from binary string.

Exports the BIGNUM value in binary string.

```lua local b, err = require("resty.openssl.bn").from_binary(ngx.decode_base64("WyU=")) local bin, err = b:to_binary() ngx.say(ngx.encode_base64(bin)) -- outputs "WyU=" ```

[Back to TOC](#table-of-contents)

### bn.from_hex, bn:to_hex

**syntax**: *bn, err = bn.from_hex(hex)*

**syntax**: *hex, err = bn:to_hex()*

Creates a `bn` instance from hex encoded string. Note that the leading `0x` should not be included. A leading `-` indicating the sign may be included.

Exports the `bn` instance to hex encoded string.

```lua local bn = require("resty.openssl.bn") local b = bn.from_hex("5B25") local hex, err = b:to_hex() ngx.say(hex) -- outputs "5B25" ```

[Back to TOC](#table-of-contents)

### bn.from_dec, bn:to_dec

**syntax**: *bn, err = bn.from_dec(dec)*

**syntax**: *dec, err = bn:to_dec()*

Creates a `bn` instance from decimal string. A leading `-` indicating the sign may be included.

Exports the `bn` instance to decimal string.

```lua local bn = require("resty.openssl.bn") local b = bn.from_dec("23333") local dec, err = b:to_dec() ngx.say(dec) -- outputs "23333" ```

[Back to TOC](#table-of-contents)

### bn:to_number

**syntax**: *n, err = bn:to_number()*

**syntax**: *n, err = bn:tonumber()*

Export the lowest 32 bits or 64 bits part (based on the ABI) of `bn` instance to a number. This is useful when user wants to perform bitwise operations.

```lua local bn = require("resty.openssl.bn") local b = bn.from_dec("23333") local n, err = b:to_number() ngx.say(n) -- outputs 23333 ngx.say(type(n)) -- outputs "number" ```

[Back to TOC](#table-of-contents)

### bn:__metamethods

Various mathematical operations can be performed as if it's a number.

```lua local bn = require("resty.openssl.bn") local a = bn.new(123456) local b = bn.new(222) -- the following returns a bn local r r = -a r = a + b r = a - b r = a * b r = a / b -- equal to bn:idiv, returns floor division r = a % b -- all operations can be performed between number and bignum r = a + 222 r = 222 + a -- the following returns a bool local bool bool = a < b bool = a >= b -- compare between number will not work -- WRONG: bool = a < 222 ```

[Back to TOC](#table-of-contents)

### bn:add, bn:sub, bn:mul, bn:div, bn:exp, bn:mod, bn:gcd

**syntax**: *r = a:op(b)*

**syntax**: *r = bn.op(a, b)*

Perform mathematical operations `op`.

- `add`: add - `sub`: subtract - `mul`: multiply - `div`, `idiv`: floor division (division with rounding down to nearest integer) - `exp`, `pow`: the `b`-th power of `a`, this function is faster than repeated `a * a * ...`. - `mod`: modulo - `gcd`: the greatest common divider of `a` and `b`.

Note that `add`, `sub`, `mul`, `div`, `mod` is also available with `+, -, *, /, %` operaters. See [above section](#bn__metamethods) for examples.

```lua local bn = require("resty.openssl.bn") local a = bn.new(123456) local b = bn.new(9876) local r -- the followings are equal r = a:add(b) r = bn.add(a, b) r = a:add(9876) r = bn.add(a, 9876) r = bn.add(123456, b) r = bn.add(123456, 9876) ```

[Back to TOC](#table-of-contents)

### bn:sqr

**syntax**: *r = a:sqr()*

**syntax**: *r = bn.sqr(a)*

Computes the 2-th power of `a`. This function is faster than `r = a * a`.

[Back to TOC](#table-of-contents)

### bn:mod_add, bn:mod_sub, bn:mod_mul, bn:mod_exp

**syntax**: *r = a:op(b, m)*

**syntax**: *r = bn.op(a, b, m)*

Perform modulo mathematical operations `op`.

- `mod_add`: adds `a` to `b` modulo `m` - `mod_sub`: substracts `b` from `a` modulo `m` - `mod_mul`: multiplies `a` by `b` and finds the non-negative remainder respective to modulus `m` - `mod_exp`, `mod_pow`: computes `a` to the `b`-th power modulo `m` (r=a^b % m). This function uses less time and space than `exp`. Do not call this function when `m` is even and any of the parameters have the `BN_FLG_CONSTTIME` flag set.

```lua local bn = require("resty.openssl.bn") local a = bn.new(123456) local b = bn.new(9876) local r -- the followings are equal r = a:mod_add(b, 3) r = bn.mod_add(a, b, 3) r = a:mod_add(9876, 3) r = bn.mod_add(a, 9876, 3) r = bn.mod_add(123456, b, 3) r = bn.mod_add(123456, 9876, 3) ```

[Back to TOC](#table-of-contents)

### bn:mod_sqr

**syntax**: *r = a:mod_sqr(m)*

**syntax**: *r = bn.mod_sqr(a, m)*

Takes the square of `a` modulo `m`.

[Back to TOC](#table-of-contents)

### bn:lshift, bn:rshift

**syntax**: *r = bn:lshift(bit)*

**syntax**: *r = bn.lshift(a, bit)*

**syntax**: *r = bn:rshift(bit)*

**syntax**: *r = bn.rshift(a, bit)*

Bit shift `a` to `bit` bits.

[Back to TOC](#table-of-contents)

### bn:is_zero, bn:is_one, bn:is_odd, bn:is_word

**syntax**: *ok = bn:is_zero()*

**syntax**: *ok = bn:is_one()*

**syntax**: *ok = bn:is_odd()*

**syntax**: *ok, err = bn:is_word(n)*

Checks if `bn` is `0`, `1`, and odd number or a number `n` respectively.

[Back to TOC](#table-of-contents)

### bn:is_prime

**syntax**: *ok, err = bn:is_prime(nchecks?)*

Checks if `bn` is a prime number. Returns `true` if it is prime with an error probability of less than 0.25^`nchecks` and error if any. If omitted, `nchecks` is set to 0 which means to select number of iterations basedon the size of the number

> This function perform a Miller-Rabin probabilistic primality test with nchecks iterations. If nchecks == BN_prime_checks (0), a number of iterations is used that yields a false positive rate of at most 2^-64 for random input. The error rate depends on the size of the prime and goes down for bigger primes. The rate is 2^-80 starting at 308 bits, 2^-112 at 852 bits, 2^-128 at 1080 bits, 2^-192 at 3747 bits and 2^-256 at 6394 bits.

> When the source of the prime is not random or not trusted, the number of checks needs to be much higher to reach the same level of assurance: It should equal half of the targeted security level in bits (rounded up to the next integer if necessary). For instance, to reach the 128 bit security level, nchecks should be set to 64.

See also [BN_is_prime(3)](https://www.openssl.org/docs/manmaster/man3/BN_is_prime.html).

[Back to TOC](#table-of-contents)

## resty.openssl.cipher

Module to interact with symmetric cryptography (EVP_CIPHER).

[Back to TOC](#table-of-contents)

### cipher.new

**syntax**: *d, err = cipher.new(cipher_name)*

Creates a cipher instance. `cipher_name` is a case-insensitive string of cipher algorithm name. To view a list of cipher algorithms implemented, use `openssl list -cipher-algorithms`.

[Back to TOC](#table-of-contents)

### cipher.istype

**syntax**: *ok = cipher.istype(table)*

Returns `true` if table is an instance of `cipher`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### cipher:encrypt

**syntax**: *s, err = cipher:encrypt(key, iv?, s, no_padding?, aead_aad?)*

Encrypt the text `s` with key `key` and IV `iv`. Returns the encrypted text in raw binary string and error if any. Optionally accepts a boolean `no_padding` which tells the cipher to enable or disable padding and default to `false` (enable padding). If `no_padding` is `true`, the length of `s` must then be a multiple of the block size or an error will occur.

When using GCM or CCM mode or `chacha20-poly1305` cipher, it's also possible to pass the Additional Authenticated Data (AAD) as the fifth argument.

This function is a shorthand of `cipher:init`, `cipher:set_aead_aad` (if appliable) then `cipher:final`.

[Back to TOC](#table-of-contents)

### cipher:decrypt

**syntax**: *s, err = cipher:decrypt(key, iv?, s, no_padding?, aead_aad?, aead_tag?)*

Decrypt the text `s` with key `key` and IV `iv`. Returns the decrypted text in raw binary string and error if any. Optionally accepts a boolean `no_padding` which tells the cipher to enable or disable padding and default to `false` (enable padding). If `no_padding` is `true`, the length of `s` must then be a multiple of the block size or an error will occur; also, padding in the decrypted text will not be removed.

When using GCM or CCM mode or `chacha20-poly1305` cipher, it's also possible to pas the Additional Authenticated Data (AAD) as the fifth argument and authentication tag as the sixth argument.

This function is a shorthand of `cipher:init`, `cipher:set_aead_aad` (if appliable), `cipher:set_aead_tag` (if appliable) then `cipher:final`.

[Back to TOC](#table-of-contents)

### cipher:init

**syntax**: *ok, err = cipher:init(key, iv?, opts?)*

Initialize the cipher with key `key` and IV `iv`. The optional third argument is a table consists of:

```lua { is_encrypt = false, no_padding = false, } ```

Calling function is needed before [cipher:update](#restycipherupdate) and [cipher:final](#restycipherfinal) if the cipher is not being initialized already. But not [cipher:encrypt](#restycipherencrypt) and [cipher:decrypt](#restycipherdecrypt).

If you wish to reuse `cipher` instance multiple times, calling this function is necessary to clear the internal state of the cipher. The shorthand functions [cipher:encrypt](#restycipherencrypt) and [cipher:decrypt](#restycipherdecrypt) already take care of initialization and reset.

[Back to TOC](#table-of-contents)

### cipher:update

**syntax**: *s, err = cipher:update(partial, ...)*

Updates the cipher with one or more strings. If the cipher has larger than block size of data to flush, the function will return a non-empty string as first argument. This function can be used in a streaming fashion to encrypt or decrypt continous data stream.

[Back to TOC](#table-of-contents)

### cipher:update_aead_aad

**syntax**: *ok, err = cipher:update_aead_aad(aad)*

Provides AAD data to the cipher, this function can be called more than one times.

[Back to TOC](#table-of-contents)

### cipher:get_aead_tag

**syntax**: *tag, err = cipher:get_aead_tag(size?)*

Gets the authentication tag from cipher with length specified as `size`. If omitted, a tag with length of half of the block size will be returned. The size cannot exceed block size.

This function can only be called after encryption is finished.

[Back to TOC](#table-of-contents)

### cipher:set_aead_tag

**syntax**: *ok, err = cipher:set_aead_tag(tag)*

Set the authentication tag of cipher with `tag`.

This function can only be called before decryption starts.

[Back to TOC](#table-of-contents)

### cipher:final

**syntax**: *s, err = cipher:final(partial?)*

Returns the encrypted or decrypted text in raw binary string, optionally accept one string to encrypt or decrypt.

```lua -- encryption local c, err = require("resty.openssl.cipher").new("aes256") c:init(string.rep("0", 32), string.rep("0", 16), { is_encrypt = true, }) c:update("🦢") local cipher, err = c:final() ngx.say(ngx.encode_base64(cipher)) -- outputs "vGJRHufPYrbbnYYC0+BnwQ==" -- OR: local c, err = require("resty.openssl.cipher").new("aes256") local cipher, err = c:encrypt(string.rep("0", 32), string.rep("0", 16), "🦢") ngx.say(ngx.encode_base64(cipher)) -- outputs "vGJRHufPYrbbnYYC0+BnwQ=="

-- decryption local encrypted = ngx.decode_base64("vGJRHufPYrbbnYYC0+BnwQ==") local c, err = require("resty.openssl.cipher").new("aes256") c:init(string.rep("0", 32), string.rep("0", 16), { is_encrypt = false, }) c:update(encrypted) local cipher, err = c:final() ngx.say(cipher) -- outputs "🦢" -- OR: local c, err = require("resty.openssl.cipher").new("aes256") local cipher, err = c:decrypt(string.rep("0", 32), string.rep("0", 16), encrypted) ngx.say(cipher) -- outputs "🦢" ```

**Note:** in some implementations like `libsodium` or Java, AEAD ciphers append the `tag` (or `MAC`) at the end of encrypted ciphertext. In such case, user will need to manually cut off the `tag` with correct size(usually 16 bytes) and pass in the ciphertext and `tag` seperately.

See [examples/aes-gcm-aead.lua](https://github.com/fffonion/lua-resty-openssl/blob/master/examples/aes-gcm-aead.lua) for an example to use AEAD modes with authentication.

[Back to TOC](#table-of-contents)

### cipher:derive

**syntax**: *key, iv, err = cipher:derive(key, salt?, count?, md?)*

Derive a key and IV (if appliable) from given material that can be used in current cipher. This function is useful mainly to work with keys that were already derived from same algorithm. Newer applications should use a more modern algorithm such as PBKDF2 provided by [kdf.derive](#kdfderive).

`count` is the iteration count to perform. If it's omitted, it's set to `1`. Note the recent version of `openssl enc` cli tool automatically use PBKDF2 if `-iter` is set to larger than 1, while this function will not. To use PBKDF2 to derive a key, please refer to [kdf.derive](#kdfderive).

`md` is the message digest name to use, it can take one of the values `md2`, `md5`, `sha` or `sha1`. If it's omitted, it's default to `sha1`.

```lua local cipher = require("resty.openssl.cipher").new("aes-128-cfb") local key, iv, err = cipher:derive("x") -- equivalent to `openssl enc -aes-128-cfb -pass pass:x -nosalt -P -md sha1` ```

[Back to TOC](#table-of-contents)

## resty.openssl.digest

Module to interact with message digest (EVP_MD_CTX).

[Back to TOC](#table-of-contents)

### digest.new

**syntax**: *d, err = digest.new(digest_name?)*

Creates a digest instance. `digest_name` is a case-insensitive string of digest algorithm name. To view a list of digest algorithms implemented, use `openssl list -digest-algorithms`.

If `digest_name` is omitted, it's default to `sha1`. Specially, the digest_name `"null"` represents a "null" message digest that does nothing: i.e. the hash it returns is of zero length.

[Back to TOC](#table-of-contents)

### digest.istype

**syntax**: *ok = digest.istype(table)*

Returns `true` if table is an instance of `digest`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### digest:update

**syntax**: *ok, err = digest:update(partial, ...)*

Updates the digest with one or more strings.

[Back to TOC](#table-of-contents)

### digest:final

**syntax**: *str, err = digest:final(partial?)*

Returns the digest in raw binary string, optionally accept one string to digest.

```lua local d, err = require("resty.openssl.digest").new("sha256") d:update("🦢") local digest, err = d:final() ngx.say(ngx.encode_base64(digest)) -- outputs "tWW/2P/uOa/yIV1gRJySJLsHq1xwg0E1RWCvEUDlla0=" -- OR: local d, err = require("resty.openssl.digest").new("sha256") local digest, err = d:final("🦢") ngx.say(ngx.encode_base64(digest)) -- outputs "tWW/2P/uOa/yIV1gRJySJLsHq1xwg0E1RWCvEUDlla0=" ```

[Back to TOC](#table-of-contents)

### digest:reset

**syntax**: *ok, err = digest:reset()*

Reset the internal state of `digest` instance as it's just created by [digest:new](#digestnew). It calls [EVP_DigestInit_ex](https://www.openssl.org/docs/manmaster/man3/EVP_DigestInit_ex.html) under the hood.

[Back to TOC](#table-of-contents)

## resty.openssl.hmac

Module to interact with hash-based message authentication code (HMAC_CTX).

[Back to TOC](#table-of-contents)

### hmac.new

**syntax**: *h, err = hmac.new(key, digest_name?)*

Creates a hmac instance. `digest_name` is a case-insensitive string of digest algorithm name. To view a list of digest algorithms implemented, use `openssl list -digest-algorithms`.

If `digest_name` is omitted, it's default to `sha1`.

[Back to TOC](#table-of-contents)

### hmac.istype

**syntax**: *ok = hmac.istype(table)*

Returns `true` if table is an instance of `hmac`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### hmac:update

**syntax**: *ok, err = hmac:update(partial, ...)*

Updates the HMAC with one or more strings.

[Back to TOC](#table-of-contents)

### hmac:final

**syntax**: *str, err = hmac:final(partial?)*

Returns the HMAC in raw binary string, optionally accept one string to digest.

```lua local d, err = require("resty.openssl.hmac").new("goose", "sha256") d:update("🦢") local hmac, err = d:final() ngx.say(ngx.encode_base64(hmac)) -- outputs "k2UcrRp25tj1Spff89mJF3fAVQ0lodq/tJT53EYXp0c=" -- OR: local d, err = require("resty.openssl.hmac").new("goose", "sha256") local hmac, err = d:final("🦢") ngx.say(ngx.encode_base64(hmac)) -- outputs "k2UcrRp25tj1Spff89mJF3fAVQ0lodq/tJT53EYXp0c=" ```

[Back to TOC](#table-of-contents)

### hmac:reset

**syntax**: *ok, err = hmac:reset()*

Reset the internal state of `hmac` instance as it's just created by [hmac:new](#hmacnew). It calls [HMAC_Init_ex](https://www.openssl.org/docs/manmaster/man3/HMAC_Init_ex.html) under the hood.

[Back to TOC](#table-of-contents)

## resty.openssl.kdf

Module to interact with KDF (key derivation function).

[Back to TOC](#table-of-contents)

### kdf.derive

**syntax**: *key, err = kdf.derive(options)*

Derive a key from given material. Various KDFs are supported based on OpenSSL version:

- On OpenSSL 1.0.2 and later, `PBKDF2`([RFC 2898], [NIST SP 800-132]) is available. - On OpenSSL 1.1.0 and later, `HKDF`([RFC 5869]), `TLS1-PRF`([RFC 2246], [RFC 5246] and [NIST SP 800-135 r1]) and `scrypt`([RFC 7914]) is available.

`options` is a table that contains:

| Key | Type | Description | Required or default | | ------------ | ---- | ----------- | ------ | | type | number | Type of KDF function to use, one of `kdf.PBKDF2`, `kdf.SCRYPT`, `kdf.TLS1_PRF` or `kdf.HKDF` | **required** | | outlen | number | Desired key length to derive | **required** | | pass | string | Initial key material to derive from | (empty string) | | salt | string | Add some salt | (empty string) | | md | string | Message digest method name to use, not effective for `scrypt` type | `"sha1"` | | pbkdf2_iter | number | PBKDF2 iteration count. RFC 2898 suggests an iteration count of at least 1000. Any value less than 1 is treated as a single iteration. | `1` | | hkdf_key | string | HKDF key | **required** | | hkdf_mode | number | HKDF mode to use, one of `kdf.HKDEF_MODE_EXTRACT_AND_EXPAND`, `kdf.HKDEF_MODE_EXTRACT_ONLY` or `kdf.HKDEF_MODE_EXPAND_ONLY`. This is only effective with OpenSSL >= 1.1.1. To learn about mode, please refer to [EVP_PKEY_CTX_set1_hkdf_key(3)](https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_CTX_set1_hkdf_key.html). Note with `kdf.HKDEF_MODE_EXTRACT_ONLY`, `outlen` is ignored and the output will be fixed size of `HMAC-<md>`. | `kdf.HKDEF_MODE_EXTRACT_AND_EXPAND`| | hkdf_info | string | HKDF info value | (empty string) | | tls1_prf_secret | string | TLS1-PRF secret | **required** | | tls1_prf_seed | string | TLS1-PRF seed | **required** | | scrypt_maxmem | number | Scrypt maximum memory usage in bytes |`32 * 1024 * 1024` | | scrypt_N | number | Scrypt CPU/memory cost parameter, must be a power of 2 | **required** | | scrypt_r | number | Scrypt blocksize parameter (8 is commonly used) | **required** | | scrypt_p | number | Scrypt parallelization parameter | **required** |

```lua local kdf = require("resty.openssl.kdf") local key, err = kdf.derive({ type = kdf.PBKDF2, outlen = 16, pass = "1234567", md = "md5", pbkdf2_iter = 1000, }) ngx.say(ngx.encode_base64(key)) -- outputs "cDRFLQ7NWt+AP4i0TdBzog=="

key, err = kdf.derive({ type = kdf.SCRYPT, outlen = 16, pass = "1234567", scrypt_N = 1024, scrypt_r = 8, scrypt_p = 16, }) ngx.say(ngx.encode_base64(key)) -- outputs "9giFtxace5sESmRb8qxuOw==" ```

[Back to TOC](#table-of-contents)

## resty.openssl.objects

Helpfer module on ASN1_OBJECT.

[Back to TOC](#table-of-contents)

### objects.obj2table

**syntax**: *tbl = objects.bytes(asn1_obj)*

Convert a ASN1_OBJECT pointer to a Lua table where

``` { id: OID of the object, nid: NID of the object, sn: short name of the object, ln: long name of the object, } ```

[Back to TOC](#table-of-contents)

### objects.nid2table

**syntax**: *tbl, err = objects.nid2table(nid)*

Convert a [NID] to a Lua table, returns the same format as [objects.obj2table](#objectsobj2table)

[Back to TOC](#table-of-contents)

### objects.txt2nid

**syntax**: *nid, err = objects.txt2nid(txt)*

Convert a text representation to [NID].

[Back to TOC](#table-of-contents)

## resty.openssl.rand

Module to interact with random number generator.

[Back to TOC](#table-of-contents)

### rand.bytes

**syntax**: *str, err = rand.bytes(length)*

Generate random bytes with length of `length`.

[Back to TOC](#table-of-contents)

## resty.openssl.x509

Module to interact with X.509 certificates.

[Back to TOC](#table-of-contents)

### x509.new

**syntax**: *crt, err = x509.new(txt?, fmt?)*

Creates a `x509` instance. `txt` can be **PEM** or **DER** formatted text; `fmt` is a choice of `PEM`, `DER` to load specific format, or `*` for auto detect.

When `txt` is omitted, `new()` creates an empty `x509` instance.

[Back to TOC](#table-of-contents)

### x509.dup

**syntax**: *x509, err = x509.dup(x509_ptr_cdata)*

Duplicates a `X509*` to create a new `x509` instance.

[Back to TOC](#table-of-contents)

### x509.istype

**syntax**: *ok = x509.istype(table)*

Returns `true` if table is an instance of `x509`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### x509:digest

**syntax**: *d, err = x509:digest(digest_name?)*

Returns a digest of the DER representation of the X509 certificate object in raw binary text.

`digest_name` is a case-insensitive string of digest algorithm name. To view a list of digest algorithms implemented, use `openssl list -digest-algorithms`.

If `digest_name` is omitted, it's default to `sha1`.

[Back to TOC](#table-of-contents)

### x509:pubkey_digest

**syntax**: *d, err = x509:pubkey_digest(digest_name?)*

Returns a digest of the DER representation of the pubkey in the X509 object in raw binary text.

`digest_name` is a case-insensitive string of digest algorithm name. To view a list of digest algorithms implemented, use `openssl list -digest-algorithms`.

If `digest_name` is omitted, it's default to `sha1`.

[Back to TOC](#table-of-contents)

### x509:get_*, x509:set_*

**syntax**: *ok, err = x509:set_attribute(instance)*

**syntax**: *instance, err = x509:get_attribute()*

Setters and getters for x509 attributes share the same syntax.

| Attribute name | Type | Description | | ------------ | ---- | ----------- | | issuer_name | [x509.name](#restyopensslx509name) | Issuer of the certificate | | not_before | number | Unix timestamp when certificate is not valid before | | not_after | number | Unix timestamp when certificate is not valid after | | pubkey | [pkey](#restyopensslpkey) | Public key of the certificate | | serial_number | [bn](#restyopensslbn) | Serial number of the certficate | | subject_name | [x509.name](#restyopensslx509name) | Subject of the certificate | | version | number | Version of the certificate, value is one less than version. For example, `2` represents `version 3` |

Additionally, getters and setters for extensions are also available:

| Extension name | Type | Description | | ------------ | ---- | ----------- | | subject_alt_name | [x509.altname](#restyopensslx509altname) | [Subject Alternative Name](https://tools.ietf.org/html/rfc5280#section-4.2.1.6) of the certificate, SANs are usually used to define "additional Common Names" | | issuer_alt_name | [x509.altname](#restyopensslx509altname) | [Issuer Alternative Name](https://tools.ietf.org/html/rfc5280#section-4.2.1.7) of the certificate | | basic_constraints | table, { ca = bool, pathlen = int} | [Basic Constriants](https://tools.ietf.org/html/rfc5280#section-4.2.1.9) of the certificate | | info_access | [x509.extension.info_access](#restyopensslx509extensioninfo_access) | [Authority Information Access](https://tools.ietf.org/html/rfc5280#section-4.2.2.1) of the certificate, contains information like OCSP reponder URL. | | crl_distribution_points | [x509.extension.dist_points](#restyopensslx509extensiondist_points) | [CRL Distribution Points](https://tools.ietf.org/html/rfc5280#section-4.2.1.13) of the certificate, contains information like Certificate Revocation List(CRL) URLs. |

For all extensions, `get_{extension}_critical` and `set_{extension}_critical` is also supported to access the `critical` flag of the extension.

If the attribute is not found, getter will return `nil, nil`.

```lua local x509, err = require("resty.openssl.x509").new() err = x509:set_not_before(ngx.time()) local not_before, err = x509:get_not_before() ngx.say(not_before) -- outputs 1571875065

err = x509:set_basic_constraints_critical(true) ```

If type is a table, setter requires a table with case-insensitive keys to set; getter returns the value of the given case-insensitive key or a table of all keys if no key provided.

```lua local x509, err = require("resty.openssl.x509").new() err = x509:set_basic_constraints({ cA = false, pathlen = 0, })

ngx.say(x509:get_basic_constraints("pathlen")) -- outputs 0

ngx.say(x509:get_basic_constraints()) -- outputs '{"ca":false,"pathlen":0}' ```

Note that user may also access the certain extension by [x509:get_extension](#x509get_extension) and [x509:set_extension](#x509set_extension), while the later two function returns or requires [extension](#restyopensslx509extension) instead. User may use getter and setters listed here if modification of current extensions is needed; use [x509:get_extension](#x509get_extension) or [x509:set_extension](#x509set_extension) if user are adding or replacing the whole extension or getters/setters are not implemented. If the getter returned a type of `x509.*` instance, it can be converted to a [extension](#restyopensslx509extension) instance by [extension:from_data](#extensionfrom_data), and thus used by [x509:get_extension](#x509get_extension) and [x509:set_extension](#x509set_extension)

[Back to TOC](#table-of-contents)

### x509:get_lifetime

**syntax**: *not_before, not_after, err = x509:get_lifetime()*

A shortcut of `x509:get_not_before` plus `x509:get_not_after`

[Back to TOC](#table-of-contents)

### x509:set_lifetime

**syntax**: *ok, err = x509:set_lifetime(not_before, not_after)*

A shortcut of `x509:set_not_before` plus `x509:set_not_after`.

[Back to TOC](#table-of-contents)

### x509:get_extension

**syntax**: *extension, pos, err = x509:get_extension(nid_or_txt, last_pos?)*

Get X.509 `extension` matching the given [NID] to certificate, returns a [resty.openssl.x509.extension](#restyopensslx509extension) instance and the found position.

If `last_pos` is defined, the function searchs from that position; otherwise it finds from beginning. Index is 1-based.

```lua local ext, pos, err = x509:get_extension("keyUsage") ngx.say(ext:text()) -- outputs "Digital Signature, Key Encipherment"

local ext, pos, err = x509:get_extension("subjectKeyIdentifier") ngx.say(ext:text()) -- outputs "3D:42:13:57:8F:79:BE:30:7D:86:A9:AC:67:50:E5:56:3E:0E:AF:4F" ```

[Back to TOC](#table-of-contents)

### x509:add_extension

**syntax**: *ok, err = x509:add_extension(extension)*

Adds an X.509 `extension` to certificate, the first argument must be a [resty.openssl.x509.extension](#restyopensslx509extension) instance.

```lua local extension, err = require("resty.openssl.x509.extension").new( "keyUsage", "critical,keyCertSign,cRLSign" ) local x509, err = require("resty.openssl.x509").new() local ok, err = x509:add_extension(extension) ```

[Back to TOC](#table-of-contents)

### x509:set_extension

**syntax**: *ok, err = x509:set_extension(extension, last_pos?)*

Adds an X.509 `extension` to certificate, the first argument must be a [resty.openssl.x509.extension](#restyopensslx509extension) instance. The difference from [x509:add_extension](#x509add_extension) is that in this function if a `extension` with same type already exists, the old extension will be replaced.

If `last_pos` is defined, the function replaces the same extension from that position; otherwise it finds from beginning. Index is 1-based. Returns `nil, nil` if not found.

Note this function is not thread-safe.

[Back to TOC](#table-of-contents)

### x509:get_extension_critical

**syntax**: *ok, err = x509:get_extension_critical(nid_or_txt)*

Get critical flag of the X.509 `extension` matching the given [NID] from certificate.

[Back to TOC](#table-of-contents)

### x509:set_extension_critical

**syntax**: *ok, err = x509:set_extension_critical(nid_or_txt, crit?)*

Set critical flag of the X.509 `extension` matching the given [NID] to certificate.

[Back to TOC](#table-of-contents)

### x509:get_ocsp_url

**syntax**: *url_or_urls, err = x509:get_ocsp_url(return_all?)*

Get OCSP URL(s) of the X.509 object. If `return_all` is set to true, returns a table containing all OCSP URLs; otherwise returns a string with first OCSP URL found. Returns `nil` if the extension is not found.

[Back to TOC](#table-of-contents)

### x509:get_crl_url

**syntax**: *url_or_urls, err = x509:get_crl_url(return_all?)*

Get CRL URL(s) of the X.509 object. If `return_all` is set to true, returns a table containing all CRL URLs; otherwise returns a string with first CRL URL found. Returns `nil` if the extension is not found.

[Back to TOC](#table-of-contents)

### x509:sign

**syntax**: *ok, err = x509:sign(pkey, digest?)*

Sign the certificate using the private key specified by `pkey`, which must be a [resty.openssl.pkey](#restyopensslpkey) that stores private key. Optionally accept `digest` parameter to set digest method, whichmust be a [resty.openssl.digest](#restyopenssldigest) instance. Returns a boolean indicating if signing is successful and error if any.

[Back to TOC](#table-of-contents)

### x509:verify

**syntax**: *ok, err = x509:verify(pkey)*

Verify the certificate signature using the public key specified by `pkey`, which must be a [resty.openssl.pkey](#restyopensslpkey). Returns a boolean indicating if verification is successful and error if any.

[Back to TOC](#table-of-contents)

### x509:tostring

**syntax**: *str, err = x509:tostring(fmt?)*

Outputs certificate in PEM-formatted text or DER-formatted binary. The first argument can be a choice of `PEM` or `DER`; when omitted, this function outputs PEM by default.

[Back to TOC](#table-of-contents)

### x509:to_PEM

**syntax**: *pem, err = x509:to_PEM()*

Outputs the certificate in PEM-formatted text.

[Back to TOC](#table-of-contents)

## resty.openssl.x509.csr

Module to interact with certificate signing request (X509_REQ).

See [examples/csr.lua](https://github.com/fffonion/lua-resty-openssl/blob/master/examples/csr.lua) for an example to generate CSR.

[Back to TOC](#table-of-contents)

### csr.new

**syntax**: *csr, err = csr.new(txt?, fmt?)*

Create an empty `csr` instance. `txt` can be **PEM** or **DER** formatted text; `fmt` is a choice of `PEM`, `DER` to load specific format, or `*` for auto detect.

When `txt` is omitted, `new()` creates an empty `csr` instance.

[Back to TOC](#table-of-contents)

### csr.istype

**syntax**: *ok = csr.istype(table)*

Returns `true` if table is an instance of `csr`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### csr:get_*, csr:set_*

**syntax**: *ok, err = csr:set_attribute(instance)*

**syntax**: *instance, err = csr:get_attribute()*

Setters and getters for x509 attributes share the same syntax.

| Attribute name | Type | Description | | ------------ | ---- | ----------- | | pubkey | [pkey](#restyopensslpkey) | Public key of the certificate request | | subject_name | [x509.name](#restyopensslx509name) | Subject of the certificate request | | version | number | Version of the certificate request, value is one less than version. For example, `2` represents `version 3` |

Additionally, getters and setters for extensions are also available:

| Extension name | Type | Description | | ------------ | ---- | ----------- | | subject_alt_name | [x509.altname](#restyopensslx509altname) | [Subject Alternative Name](https://tools.ietf.org/html/rfc5280#section-4.2.1.6) of the certificate request, SANs are usually used to define "additional Common Names" |

For all extensions, `get_{extension}_critical` and `set_{extension}_critical` is also supported to access the `critical` flag of the extension.

If the attribute is not found, getter will return `nil, nil`.

```lua local csr, err = require("resty.openssl.csr").new() err = csr:set_version(3) local version, err = csr:get_version() ngx.say(version) -- outputs 3 ```

Note that user may also access the certain extension by [csr:get_extension](#csrget_extension) and [csr:set_extension](#csrset_extension), while the later two function returns or requires [extension](#restyopensslx509extension) instead. User may use getter and setters listed here if modification of current extensions is needed; use [csr:get_extension](#csrget_extension) or [csr:set_extension](#csrset_extension) if user are adding or replacing the whole extension or getters/setters are not implemented. If the getter returned a type of `x509.*` instance, it can be converted to a [extension](#restyopensslx509extension) instance by [extension:from_data](#extensionfrom_data), and thus used by [csr:get_extension](#csrget_extension) and [csr:set_extension](#csrset_extension)

[Back to TOC](#table-of-contents)

### csr:set_subject_alt

Same as [csr:set_subject_alt_name](#csrget_-csrset_), this function is deprecated to align with naming convension with other functions.

[Back to TOC](#table-of-contents)

### csr:get_extension

**syntax**: *extension, pos, err = csr:get_extension(nid_or_txt, pos?)*

Get X.509 `extension` matching the given [NID] to certificate, returns a [resty.openssl.x509.extension](#restyopensslx509extension) instance and the found position.

If `last_pos` is defined, the function searchs from that position; otherwise it finds from beginning. Index is 1-based.

```lua local ext, pos, err = csr:get_extension("basicConstraints") ```

[Back to TOC](#table-of-contents)

### csr:get_extensions

**syntax**: *extensions, err = csr:get_extensions()*

Return all extensions as a [resty.openssl.x509.extensions](#restyopensslx509extensions) instance.

[Back to TOC](#table-of-contents)

### csr:add_extension

**syntax**: *ok, err = csr:add_extension(extension)*

Adds an X.509 `extension` to csr, the first argument must be a [resty.openssl.x509.extension](#restyopensslx509extension) instance.

[Back to TOC](#table-of-contents)

### csr:set_extension

**syntax**: *ok, err = csr:set_extension(extension)*

Adds an X.509 `extension` to csr, the first argument must be a [resty.openssl.x509.extension](#restyopensslx509extension) instance. The difference from [csr:add_extension](#csradd_extension) is that in this function if a `extension` with same type already exists, the old extension will be replaced.

Note this function is not thread-safe.

[Back to TOC](#table-of-contents)

### csr:get_extension_critical

**syntax**: *ok, err = csr:get_extension_critical(nid_or_txt)*

Get critical flag of the X.509 `extension` matching the given [NID] from csr.

[Back to TOC](#table-of-contents)

### csr:set_extension_critical

**syntax**: *ok, err = csr:set_extension_critical(nid_or_txt, crit?)*

Set critical flag of the X.509 `extension` matching the given [NID] to csr.

[Back to TOC](#table-of-contents)

### csr:sign

**syntax**: *ok, err = csr:sign(pkey, digest?)*

Sign the certificate request using the private key specified by `pkey`, which must be a [resty.openssl.pkey](#restyopensslpkey) that stores private key. Optionally accept `digest` parameter to set digest method, whichmust be a [resty.openssl.digest](#restyopenssldigest) instance. Returns a boolean indicating if signing is successful and error if any.

[Back to TOC](#table-of-contents)

### csr:verify

**syntax**: *ok, err = csr:verify(pkey)*

Verify the CSR signature using the public key specified by `pkey`, which must be a [resty.openssl.pkey](#restyopensslpkey). Returns a boolean indicating if verification is successful and error if any.

[Back to TOC](#table-of-contents)

### csr:tostring

**syntax**: *str, err = csr:tostring(fmt?)*

Outputs certificate request in PEM-formatted text or DER-formatted binary. The first argument can be a choice of `PEM` or `DER`; when omitted, this function outputs PEM by default.

[Back to TOC](#table-of-contents)

### csr:to_PEM

**syntax**: *pem, err = csr:to_PEM(?)*

Outputs CSR in PEM-formatted text.

[Back to TOC](#table-of-contents)

## resty.openssl.crl

Module to interact with X509_CRL(certificate revocation list).

[Back to TOC](#table-of-contents)

### crl.new

**syntax**: *crt, err = crl.new(txt?, fmt?)*

Creates a `crl` instance. `txt` can be **PEM** or **DER** formatted text; `fmt` is a choice of `PEM`, `DER` to load specific format, or `*` for auto detect.

When `txt` is omitted, `new()` creates an empty `crl` instance.

[Back to TOC](#table-of-contents)

### crl.dup

**syntax**: *crl, err = crl.dup(crl_ptr_cdata)*

Duplicates a `X509_CRL*` to create a new `crl` instance.

[Back to TOC](#table-of-contents)

### crl.istype

**syntax**: *ok = crl.istype(table)*

Returns `true` if table is an instance of `crl`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### crl:get_*, crl:set_*

**syntax**: *ok, err = crl:set_attribute(instance)*

**syntax**: *instance, err = crl:get_attribute()*

Setters and getters for crl attributes share the same syntax.

| Attribute name | Type | Description | | ------------ | ---- | ----------- | | issuer_name | [x509.name](#restyopensslx509name) | Issuer of the CRL | | last_update | number | Unix timestamp when CRL is not valid before | | next_update | number | Unix timestamp when CRL is not valid after | | version | number | Version of the certificate, value is one less than version. For example, `2` represents `version 3` |

Additionally, getters and setters for extensions are also available:

| Extension name | Type | Description | | ------------ | ---- | ----------- |

For all extensions, `get_{extension}_critical` and `set_{extension}_critical` is also supported to access the `critical` flag of the extension.

If the attribute is not found, getter will return `nil, nil`.

```lua local crl, err = require("resty.openssl.crl").new() err = crl:set_next_update(ngx.time()) local not_before, err = crl:get_next_update() ngx.say(not_before) -- outputs 1571875065 ```

Note that user may also access the certain extension by [crl:get_extension](#crlget_extension) and [crl:set_extension](#crlset_extension), while the later two function returns or requires [extension](#restyopensslcrlextension) instead. User may use getter and setters listed here if modification of current extensions is needed; use [crl:get_extension](#crlget_extension) or [crl:set_extension](#crlset_extension) if user are adding or replacing the whole extension or getters/setters are not implemented. If the getter returned a type of `crl.*` instance, it can be converted to a [extension](#restyopensslcrlextension) instance by [extension:from_data](#extensionfrom_data), and thus used by [crl:get_extension](#crlget_extension) and [crl:set_extension](#crlset_extension)

[Back to TOC](#table-of-contents)

### crl:get_extension

**syntax**: *extension, pos, err = crl:get_extension(nid_or_txt, last_pos?)*

Get X.509 `extension` matching the given [NID] to CRL, returns a [resty.openssl.x509.extension](#restyopensslx509extension) instance and the found position.

If `last_pos` is defined, the function searchs from that position; otherwise it finds from beginning. Index is 1-based.

[Back to TOC](#table-of-contents)

### crl:add_extension

**syntax**: *ok, err = crl:add_extension(extension)*

Adds an X.509 `extension` to CRL, the first argument must be a [resty.openssl.x509.extension](#restyopensslx509extension) instance.

[Back to TOC](#table-of-contents)

### crl:set_extension

**syntax**: *ok, err = crl:set_extension(extension, last_pos?)*

Adds an X.509 `extension` to CRL, the first argument must be a [resty.openssl.x509.extension](#restyopensslx509extension) instance. The difference from [crl:add_extension](#crladd_extension) is that in this function if a `extension` with same type already exists, the old extension will be replaced.

If `last_pos` is defined, the function replaces the same extension from that position; otherwise it finds from beginning. Index is 1-based. Returns `nil, nil` if not found.

Note this function is not thread-safe.

[Back to TOC](#table-of-contents)

### crl:get_extension_critical

**syntax**: *ok, err = crl:get_extension_critical(nid_or_txt)*

Get critical flag of the X.509 `extension` matching the given [NID] from CRL.

[Back to TOC](#table-of-contents)

### crl:set_extension_critical

**syntax**: *ok, err = crl:set_extension_critical(nid_or_txt, crit?)*

Set critical flag of the X.509 `extension` matching the given [NID] to CRL.

[Back to TOC](#table-of-contents)

### crl:add_revoked

**syntax**: *ok, err = crl:add_revoked(revoked)*

Adds a [resty.openssl.x509.revoked](#restyopensslx509revoked) instance to the CRL.

[Back to TOC](#table-of-contents)

### crl:sign

**syntax**: *ok, err = crl:sign(pkey, digest?)*

Sign the CRL using the private key specified by `pkey`, which must be a [resty.openssl.pkey](#restyopensslpkey) that stores private key. Optionally accept `digest` parameter to set digest method, whichmust be a [resty.openssl.digest](#restyopenssldigest) instance. Returns a boolean indicating if signing is successful and error if any.

[Back to TOC](#table-of-contents)

### crl:verify

**syntax**: *ok, err = crl:verify(pkey)*

Verify the CRL signature using the public key specified by `pkey`, which must be a [resty.openssl.pkey](#restyopensslpkey). Returns a boolean indicating if verification is successful and error if any.

[Back to TOC](#table-of-contents)

### crl:tostring

**syntax**: *str, err = crl:tostring(fmt?)*

Outputs CRL in PEM-formatted text or DER-formatted binary. The first argument can be a choice of `PEM` or `DER`; when omitted, this function outputs PEM by default.

[Back to TOC](#table-of-contents)

### crl:to_PEM

**syntax**: *pem, err = crl:to_PEM()*

Outputs the CRL in PEM-formatted text.

[Back to TOC](#table-of-contents)

## resty.openssl.x509.name

Module to interact with X.509 names.

[Back to TOC](#table-of-contents)

### name.new

**syntax**: *name, err = name.new()*

Creates an empty `name` instance.

[Back to TOC](#table-of-contents)

### name.dup

**syntax**: *name, err = name.dup(name_ptr_cdata)*

Duplicates a `X509_NAME*` to create a new `name` instance.

[Back to TOC](#table-of-contents)

### name.istype

**syntax**: *ok = name.istype(table)*

Returns `true` if table is an instance of `name`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### name:add

**syntax**: *name, err = name:add(nid_text, txt)*

Adds an ASN.1 object to `name`. First arguments in the *text representation* of [NID]. Second argument is the plain text value for the ASN.1 object.

Returns the name instance itself on success, or `nil` and an error on failure.

This function can be called multiple times in a chained fashion.

```lua local name, err = require("resty.openssl.x509.name").new() local _, err = name:add("CN", "example.com")

_, err = name :add("C", "US") :add("ST", "California") :add("L", "San Francisco")

```

[Back to TOC](#table-of-contents)

### name:find

**syntax**: *obj, pos, err = name:find(nid_text, last_pos?)*

Finds the ASN.1 object with the given *text representation* of [NID] from the postition of `last_pos`. By omitting the `last_pos` parameter, `find` finds from the beginning.

Returns the object in a table as same format as decribed [here](#name__metamethods), the position of the found object and error if any. Index is 1-based. Returns `nil, nil` if not found.

```lua local name, err = require("resty.openssl.x509.name").new() local _, err = name:add("CN", "example.com") :add("CN", "example2.com")

local obj, pos, err = name:find("CN") ngx.say(obj.blob, " at ", pos) -- outputs "example.com at 1" local obj, pos, err = name:find("2.5.4.3", 1) ngx.say(obj.blob, " at ", pos) -- outputs "example2.com at 2" ```

[Back to TOC](#table-of-contents)

### name:tostring

**syntax**: *txt = name:tostring()*

Outputs name in a text representation.

```lua local name, err = require("resty.openssl.x509.name").new() local _, err = name:add("CN", "example.com") :add("CN", "example2.com")

ngx.say(name:tostring()) -- outputs "CN=example.com/CN=example2.com" ```

[Back to TOC](#table-of-contents)

### name:__metamethods

**syntax**: *for k, obj in pairs(name)*

**syntax**: *len = #name*

**syntax**: *k, v = name[i]*

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with `-DLUAJIT_ENABLE_LUA52COMPAT` flag; otherwise use `all`, `each`, `index` and `count` instead.

See also [functions for stack-like objects](#functions-for-stack-like-objects).

Each returned object is a table where:

``` { id: OID of the object, nid: NID of the object, sn: short name of the object, ln: long name of the object, blob: value of the object, } ```

```lua local name, err = require("resty.openssl.x509.name").new() local _, err = name:add("CN", "example.com")

for k, obj in pairs(name) do ngx.say(k, ":", require("cjson").encode(obj)) end -- outputs 'CN: {"sn":"CN","id":"2.5.4.3","nid":13,"blob":"3.example.com","ln":"commonName"}' ```

[Back to TOC](#table-of-contents)

## resty.openssl.x509.altname

Module to interact with GENERAL_NAMES, an extension to X.509 names.

[Back to TOC](#table-of-contents)

### altname.new

**syntax**: *altname, err = altname.new()*

Creates an empty `altname` instance.

[Back to TOC](#table-of-contents)

### altname.dup

**syntax**: *altname, err = altname.dup(altname_ptr_cdata)*

Duplicates a `STACK_OF(GENERAL_NAMES)` to create a new `altname` instance. The function creates a new stack but won't duplicates elements in the stack.

[Back to TOC](#table-of-contents)

### altname.istype

**syntax**: *altname = digest.istype(table)*

Returns `true` if table is an instance of `altname`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### altname:add

**syntax**: *altname, err = altname:add(key, value)*

Adds a name to altname stack, first argument is case-insensitive and can be one of

    RFC822Name
    RFC822
    Email
    UniformResourceIdentifier
    URI
    DNSName
    DNS
    IPAddress
    IP
    DirName

This function can be called multiple times in a chained fashion.

[Back to TOC](#table-of-contents)

### altname:tostring

**syntax**: *txt = altname:tostring()*

Outputs altname in a text representation.

```lua local altname, err = require("resty.openssl.x509.altname").new()

_, err = altname :add("DNS", "2.example.com") :add("DnS", "3.example.com")

ngx.say(altname:tostring()) -- outputs "DNS=2.example.com/DNS=3.example.com" ```

[Back to TOC](#table-of-contents)

### altname:__metamethods

**syntax**: *for k, obj in pairs(altname)*

**syntax**: *len = #altname*

**syntax**: *k, v = altname[i]*

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with `-DLUAJIT_ENABLE_LUA52COMPAT` flag; otherwise use `all`, `each`, `index` and `count` instead.

See also [functions for stack-like objects](#functions-for-stack-like-objects).

[Back to TOC](#table-of-contents)

## resty.openssl.x509.extension

Module to interact with X.509 extensions.

[Back to TOC](#table-of-contents)

### extension.new

**syntax**: *ext, err = extension.new(name, value, data?)*

Creates a new `extension` instance. `name` and `value` are strings in OpenSSL [arbitrary extension format](https://www.openssl.org/docs/manmaster/man5/x509v3_config.html).

`data` can be a table, string or nil. Where `data` is a table, the following key will be looked up:

```lua data = { issuer = resty.openssl.x509 instance, subject = resty.openssl.x509 instance, request = resty.openssl.x509.csr instance, crl = resty.openssl.x509.crl instance, } ```

When `data` is a string, it's the full nconf string. Using section lookup from `value` to `data` is also supported.

<details> <summary>Example usages:</summary>

```lua local extension = require("resty.openssl.x509.extension") -- extendedKeyUsage=serverAuth,clientAuth local ext, err = extension.new("extendedKeyUsage", "serverAuth,clientAuth") -- crlDistributionPoints=URI:http://myhost.com/myca.crl ext, err = extension.new("crlDistributionPoints", "URI:http://myhost.com/myca.crl") -- with section lookup ext, err = extension.new( "crlDistributionPoints", "crldp1_section", [[ [crldp1_section] fullname=URI:http://myhost.com/myca.crl CRLissuer=dirName:issuer_sect reasons=keyCompromise, CACompromise

  [issuer_sect]
  C=UK
  O=Organisation
  CN=Some Name
  ]]
)
-- combine section lookup with other value
ext, err = extension.new(
"certificatePolicies", "ia5org,1.2.3.4,1.5.6.7.8,@polsect",
  [[
  [polsect]
  policyIdentifier = 1.3.5.8
  CPS.1="http://my.host.name/"
  CPS.2="http://my.your.name/"
  userNotice.1=@notice

  [notice]
  explicitText="Explicit Text Here"
  organization="Organisation Name"
  noticeNumbers=1,2,3,4
 ]]
))
-- subjectKeyIdentifier=hash
local x509, err = require("resty.openssl.x509").new()
ext, err =  extension.new("subjectKeyIdentifier", "hash", {
    subject = x509
})
```
</details>

See [examples/tls-alpn-01.lua](https://github.com/fffonion/lua-resty-openssl/blob/master/examples/tls-alpn-01.lua) for an example to create extension with an unknown nid.

[Back to TOC](#table-of-contents)

### extension.dup

**syntax**: *ext, err = extension.dup(extension_ptr_cdata)*

Creates a new `extension` instance from `X509_EXTENSION*` pointer.

[Back to TOC](#table-of-contents)

### extension.from_der

**syntax**: *ext, ok = extension.from_der(der, nid_or_txt, crit?)*

Creates a new `extension` instance. `der` is the ASN.1 encoded string to be set for the extension.

`nid_or_txt` is a number or text representation of [NID] and `crit` is the critical flag of the extension.

See [examples/tls-alpn-01.lua](https://github.com/fffonion/lua-resty-openssl/blob/master/examples/tls-alpn-01.lua) for an example to create extension with an unknown nid.

[Back to TOC](#table-of-contents)

### extension.from_data

**syntax**: *ext, ok = extension.from_data(table, nid_or_txt, crit?)*

Creates a new `extension` instance. `table` can be instance of:

- [x509.altname](#restyopensslx509altname) - [x509.extension.info_access](#restyopensslx509extensioninfo_access) - [x509.extension.dist_points](#restyopensslx509extensiondist_points)

`nid_or_txt` is a number or text representation of [NID] and `crit` is the critical flag of the extension.

[Back to TOC](#table-of-contents)

### extension.istype

**syntax**: *ok = extension.istype(table)*

Returns `true` if table is an instance of `extension`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### extension:get_extension_critical

**syntax**: *crit, err = extension:get_extension_critical()*

Returns `true` if extension is critical. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### extension:set_extension_critical

**syntax**: *ok, err = extension:set_extension_critical(crit)*

Set the critical flag of the extension.

[Back to TOC](#table-of-contents)

### extension:get_object

**syntax**: *obj = extension:get_object()*

Returns the name of extension as ASN.1 Object. User can further use helper functions in [resty.openssl.objects](#restyopensslobjects) to print human readable texts.

[Back to TOC](#table-of-contents)

### extension:text

**syntax**: *txt, err = extension:text()*

Returns the text representation of extension

```lua local objects = require "resty.openssl.objects" ngx.say(cjson.encode(objects.obj2table(extension:get_object()))) -- outputs '{"ln":"X509v3 Subject Key Identifier","nid":82,"sn":"subjectKeyIdentifier","id":"2.5.29.14"}' ngx.say(extension:text()) -- outputs "C9:C2:53:61:66:9D:5F:AB:25:F4:26:CD:0F:38:9A:A8:49:EA:48:A9" ```

[Back to TOC](#table-of-contents)

### extension:tostring

**syntax**: *txt, err = extension:tostring()*

Same as [extension:text](#extensiontext).

[Back to TOC](#table-of-contents)

## resty.openssl.x509.extension.dist_points

Module to interact with CRL Distribution Points(DIST_POINT stack).

[Back to TOC](#table-of-contents)

### dist_points.new

**syntax**: *dp, err = dist_points.new()*

Creates a new `dist_points` instance.

[Back to TOC](#table-of-contents)

### dist_points.dup

**syntax**: *dp, err = dist_points.dup(dist_points_ptr_cdata)*

Duplicates a `STACK_OF(DIST_POINT)` to create a new `dist_points` instance. The function creates a new stack but won't duplicates elements in the stack.

[Back to TOC](#table-of-contents)

### dist_points.istype

**syntax**: *ok = dist_points.istype(table)*

Returns `true` if table is an instance of `dist_points`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### dist_points:__metamethods

**syntax**: *for i, obj in ipairs(dist_points)*

**syntax**: *len = #dist_points*

**syntax**: *obj = dist_points[i]*

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with `-DLUAJIT_ENABLE_LUA52COMPAT` flag; otherwise use `all`, `each`, `index` and `count` instead.

See also [functions for stack-like objects](#functions-for-stack-like-objects).

Each object returned when iterrating dist_points instance is a [x509.altname](#restyopensslx509altname) instance.

```lua local x = x509.new(io.open("/path/to/a_cert_has_dist_points.crt"):read("*a"))

local cdp = x:get_crl_distribution_points()

local an = cdp[1] ngx.say(an:tostring()) -- or any other function for resty.openssl.x509.altname

for _, an in ipairs(cdp) do ngx.say(an:tostring()) end ```

[Back to TOC](#table-of-contents)

## resty.openssl.x509.extension.info_access

Module to interact with Authority Information Access data (AUTHORITY_INFO_ACCESS, ACCESS_DESCRIPTION stack).

[Back to TOC](#table-of-contents)

### info_access.new

**syntax**: *aia, err = info_access.new()*

Creates a new `info_access` instance.

[Back to TOC](#table-of-contents)

### info_access.dup

**syntax**: *aia, err = info_access.dup(info_access_ptr_cdata)*

Duplicates a `AUTHORITY_INFO_ACCESS` to create a new `info_access` instance. The function creates a new stack but won't duplicates elements in the stack.

[Back to TOC](#table-of-contents)

### info_access.istype

**syntax**: *ok = info_access.istype(table)*

Returns `true` if table is an instance of `info_access`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### info_access:add

**syntax**: *ok, err = info_access:add(x509)*

Add a `x509` object to the info_access. The first argument must be a [resty.openssl.x509](#restyopensslx509) instance.

[Back to TOC](#table-of-contents)

### info_access:__metamethods

**syntax**: *for i, obj in ipairs(info_access)*

**syntax**: *len = #info_access*

**syntax**: *obj = info_access[i]*

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with `-DLUAJIT_ENABLE_LUA52COMPAT` flag; otherwise use `all`, `each`, `index` and `count` instead.

See also [functions for stack-like objects](#functions-for-stack-like-objects).

Each object returned when iterrating dist_points instance is a table of [NID] type and values.

```lua local cjson = require("cjosn") local x509 = require("resty.openssl.x509") local crt = x509.new(io.open("/path/to/a_cert_has_info_access.crt"):read("*a"))

local aia = crt:get_info_access()

ngx.say(cjson.encode(aia[1])) -- outputs '[178,"URI","http:\/\/ocsp.starfieldtech.com\/"]'

for _, a in ipairs(aia) do ngx.say(cjson.encode(a)) end ```

[Back to TOC](#table-of-contents)

## resty.openssl.x509.extensions

Module to interact with X.509 Extension stack.

[Back to TOC](#table-of-contents)

### extensions.new

**syntax**: *ch, err = extensions.new()*

Creates a new `extensions` instance.

[Back to TOC](#table-of-contents)

### extensions.dup

**syntax**: *ch, err = extensions.dup(extensions_ptr_cdata)*

Duplicates a `STACK_OF(X509_EXTENSION)` to create a new `extensions` instance. The function creates a new stack but won't duplicates elements in the stack.

[Back to TOC](#table-of-contents)

### extensions.istype

**syntax**: *ok = extensions.istype(table)*

Returns `true` if table is an instance of `extensions`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### extensions:add

**syntax**: *ok, err = extensions:add(x509)*

Add a `x509` object to the extensions. The first argument must be a [resty.openssl.x509](#restyopensslx509) instance.

[Back to TOC](#table-of-contents)

### extensions:__metamethods

**syntax**: *for i, obj in ipairs(extensions)*

**syntax**: *len = #extensions*

**syntax**: *obj = extensions[i]*

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with `-DLUAJIT_ENABLE_LUA52COMPAT` flag; otherwise use `all`, `each`, `index` and `count` instead.

See also [functions for stack-like objects](#functions-for-stack-like-objects).

[Back to TOC](#table-of-contents)

## resty.openssl.x509.chain

Module to interact with X.509 stack.

[Back to TOC](#table-of-contents)

### chain.new

**syntax**: *ch, err = chain.new()*

Creates a new `chain` instance.

[Back to TOC](#table-of-contents)

### chain.dup

**syntax**: *ch, err = chain.dup(chain_ptr_cdata)*

Duplicates a `STACK_OF(X509)` to create a new `chain` instance. The function creates a new stack and increases reference count for all elements by 1. But it won't duplicate the elements themselves.

[Back to TOC](#table-of-contents)

### chain.istype

**syntax**: *ok = chain.istype(table)*

Returns `true` if table is an instance of `chain`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### chain:add

**syntax**: *ok, err = chain:add(x509)*

Add a `x509` object to the chain. The first argument must be a [resty.openssl.x509](#restyopensslx509) instance.

[Back to TOC](#table-of-contents)

### chain:__metamethods

**syntax**: *for i, obj in ipairs(chain)*

**syntax**: *len = #chain*

**syntax**: *obj = chain[i]*

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with `-DLUAJIT_ENABLE_LUA52COMPAT` flag; otherwise use `all`, `each`, `index` and `count` instead.

See also [functions for stack-like objects](#functions-for-stack-like-objects).

[Back to TOC](#table-of-contents)

## resty.openssl.x509.store

Module to interact with X.509 certificate store (X509_STORE).

[Back to TOC](#table-of-contents)

### store.new

**syntax**: *st, err = store.new()*

Creates a new `store` instance.

[Back to TOC](#table-of-contents)

### store.istype

**syntax**: *ok = store.istype(table)*

Returns `true` if table is an instance of `store`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

### store:use_default

**syntax**: *ok, err = store:use_default()*

Loads certificates into the X509_STORE from the hardcoded default paths.

Note that to load "default" CAs correctly, usually you need to install a CA certificates bundle. For example, the package in Debian/Ubuntu is called `ca-certificates`.

[Back to TOC](#table-of-contents)

### store:add

**syntax**: *ok, err = store:add(x509_or_crl)*

Adds a X.509 or a CRL object into store. The argument must be a [resty.openssl.x509](#restyopensslx509) instance or a [resty.openssl.x509.store](#restyopensslx509store) instance.

[Back to TOC](#table-of-contents)

### store:load_file

**syntax**: *ok, err = store:load_file(path)*

Loads a X.509 certificate on file system into store.

[Back to TOC](#table-of-contents)

### store:load_directory

**syntax**: *ok, err = store:load_directory(path)*

Loads a directory of X.509 certificates on file system into store. The certificates in the directory must be in hashed form, as documented in [X509_LOOKUP_hash_dir(3)](https://www.openssl.org/docs/manmaster/man3/X509_LOOKUP_hash_dir.html).

[Back to TOC](#table-of-contents)

### store:verify

**syntax**: *chain, err = store:verify(x509, chain?, return_chain?)*

Verifies a X.509 object with the store. The first argument must be [resty.openssl.x509](#restyopensslx509) instance. Optionally accept a validation chain as second argument, which must be a [resty.openssl.x509.chain](#restyopensslx509chain) instance.

If verification succeed, and `return_chain` is set to true, returns the proof of validation as a [resty.openssl.x509.chain](#restyopensslx509chain); otherwise returns `true` only. If verification failed, returns `nil` and error explaining the reason.

[Back to TOC](#table-of-contents)

## resty.openssl.x509.revoked

Module to interact with X509_REVOKED.

[Back to TOC](#table-of-contents)

### revoked.new

**syntax**: *ch, err = revoked.new(serial_number, time, reason)*

Creates a new `revoked` instance. `serial_number` can be either a [resty.openssl.bn](#restyopensslbn) instance or a number. `time` and `reason` must be numbers.

[Back to TOC](#table-of-contents)

### revoked.istype

**syntax**: *ok = revoked.istype(table)*

Returns `true` if table is an instance of `revoked`. Returns `false` otherwise.

[Back to TOC](#table-of-contents)

## Functions for stack-like objects

[Back to TOC](#table-of-contents)

### metamethods

**syntax**: *for k, obj in pairs(x)*

**syntax**: *for k, obj in ipairs(x)*

**syntax**: *len = #x*

**syntax**: *obj = x[i]*

Access the underlying objects as it's a Lua table. Make sure your LuaJIT compiled with `-DLUAJIT_ENABLE_LUA52COMPAT` flag.

Each object may only support either `pairs` or `ipairs`. Index is 1-based.

```lua local name, err = require("resty.openssl.x509.name").new() local _, err = name:add("CN", "example.com")

for k, obj in pairs(name) do ngx.say(k, ":", require("cjson").encode(obj)) end -- outputs 'CN: {"sn":"CN","id":"2.5.4.3","nid":13,"blob":"3.example.com","ln":"commonName"}' ```

[Back to TOC](#table-of-contents)

### each

**syntax**: *iter = x:each()*

Return an iterator to traverse objects. Use this while `LUAJIT_ENABLE_LUA52COMPAT` is not enabled.

```lua local name, err = require("resty.openssl.x509.name").new() local _, err = name:add("CN", "example.com")

local iter = name:each() while true do local k, obj = iter() if not k then break end end ```

[Back to TOC](#table-of-contents)

### all

**syntax**: *objs, err = x:all()*

Returns all objects in the table. Use this while `LUAJIT_ENABLE_LUA52COMPAT` is not enabled.

[Back to TOC](#table-of-contents)

### count

**syntax**: *len = x:count()*

Returns count of objects of the table. Use this while `LUAJIT_ENABLE_LUA52COMPAT` is not enabled.

[Back to TOC](#table-of-contents)

### index

**syntax**: *obj = x:index(i)*

Returns objects at index of `i` of the table, index is 1-based. If index is out of bound, `nil` is returned.

[Back to TOC](#table-of-contents)

General rules on garbage collection ====

- When a type is added or returned to another type, it's internal cdata is always copied. ```lua local name = require("resty.openssl.x509.name"):add("CN", "example.com") local x509 = require("resty.openssl.x509").new() -- `name` is copied when added to x509 x509:set_subject_name(name)

name:add("L", "Mars") -- subject_name in x509 will not be modified ``` - The creator set the GC handler; the user must not free it. - For a stack: - If it's created by `new()`: set GC handler to sk_TYPE_pop_free - The gc handler for elements being added to stack should not be set. Instead, rely on the gc handler of the stack to free each individual elements. - If it's created by `dup()` (shallow copy): - If elements support reference counter (like X509): increase ref count for all elements by 1; set GC handler to sk_TYPE_pop_free. - If not, set GC handler to sk_free - Additionally, the stack duplicates the element when it's added to stack, a GC handler for the duplicate must be set. But a reference should be kept in Lua land to prevent premature gc of individual elements. (See x509.altname). - Shallow copy for stack is fine because in current design user can't modify the element in the stack directly. Each elemente is duplicated when added to stack and when returned.

[Back to TOC](#table-of-contents)

Code generation ====

Lots of functions and tests for X509, CSR and CRL are generated from templates under [scripts](https://github.com/fffonion/lua-resty-openssl/tree/master/scripts) directory. Those functions and tests are either commented with `AUTO GENERATED` or `AUTOGEN`.

When making changes to them, please update the template under `scripts/templates` instead. Then regenerate them again.

``` cd scripts pip3 install -r requirements.txt python3 ./x509_autogen.py ```

[Back to TOC](#table-of-contents)

Compatibility ====

Although only a small combinations of CPU arch and OpenSSL version are tested, the library should function well as long as the linked OpenSSL library is API compatible. This means the same name of functions are exported with same argument types.

For OpenSSL 1.0.2 series however, binary/ABI compatibility must be ensured as some struct members are accessed directly. They are accessed by memory offset in assembly.

OpenSSL [keeps ABI/binary compatibility](https://wiki.openssl.org/index.php/Versioning) with minor releases or letter releases. So all structs offsets and macro constants are kept same.

If you plan to use this library on an untested version of OpenSSL (like custom builds or pre releases), [this](https://abi-laboratory.pro/index.php?view=timeline&l=openssl) can be a good source to consult.

[Back to TOC](#table-of-contents)

Credits ====

This project receives contribution from following developers:

- [@nasrullo](https://github.com/nasrullo) - [@vinayakhulawale](https://github.com/vinayakhulawale)

[Back to TOC](#table-of-contents)

Copyright and License =====================

This module is licensed under the BSD license.

Copyright (C) 2019-2020, by fffonion <fffonion@gmail.com>.

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

* Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

[Back to TOC](#table-of-contents)

See Also ======== * [luaossl](https://github.com/wahern/luaossl) * [API/ABI changes review for OpenSSL](https://abi-laboratory.pro/index.php?view=timeline&l=openssl) * [OpenSSL API manual](https://www.openssl.org/docs/man1.1.1/man3/)

[Back to TOC](#table-of-contents)

[NID]: https://github.com/openssl/openssl/blob/master/include/openssl/obj_mac.h [RFC 2246]: https://tools.ietf.org/html/rfc2246 [RFC 2898]: https://tools.ietf.org/html/rfc2898 [RFC 5246]: https://tools.ietf.org/html/rfc5246 [RFC 5869]: https://tools.ietf.org/html/rfc5869 [RFC 7914]: https://tools.ietf.org/html/rfc7914 [NIST SP 800-132]: https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-132.pdf [NIST SP 800-135 r1]: https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-135r1.pdf The gc handler for elements being added to stack should not be set. Instead, rely on the gc handler of the stack to free each individual elements.

• If it's created by dup() (shallow copy):

  • If elements support reference counter (like X509): increase ref count for all elements by 1; set GC handler to sk_TYPE_pop_free.

  • If not, set GC handler to sk_free

    • Additionally, the stack duplicates the element when it's added to stack, a GC handler for the duplicate must be set. But a reference should be kept in Lua land to prevent premature gc of individual elements. (See x509.altname).

  • Shallow copy for stack is fine because in current design user can't modify the element in the stack directly. Each elemente is duplicated when added to stack and when returned.

Code generation

Lots of functions and tests for X509, CSR and CRL are generated from templates under scripts directory. Those functions and tests are either commented with AUTO GENERATED or AUTOGEN.

When making changes to them, please update the template under scripts/templates instead. Then regenerate them again.

    cd scripts
    pip3 install -r requirements.txt
    python3 ./x509_autogen.py

Compatibility

Although only a small combinations of CPU arch and OpenSSL version are tested, the library should function well as long as the linked OpenSSL library is API compatible. This means the same name of functions are exported with same argument types.

For OpenSSL 1.0.2 series however, binary/ABI compatibility must be ensured as some struct members are accessed directly. They are accessed by memory offset in assembly.

OpenSSL keeps ABI/binary compatibility with minor releases or letter releases. So all structs offsets and macro constants are kept same.

If you plan to use this library on an untested version of OpenSSL (like custom builds or pre releases), this can be a good source to consult.

Credits

This project receives contribution from following developers:

• @nasrullo

• @vinayakhulawale

Copyright and License

This module is licensed under the BSD license.

Copyright (C) 2019-2020, by fffonion <fffonion@gmail.com>.

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

See Also

• luaossl

• API/ABI changes review for OpenSSL

• OpenSSL API manual

[NID]: https://github.com/openssl/openssl/blob/master/include/openssl/obj_mac.h [RFC 2246]: https://tools.ietf.org/html/rfc2246 [RFC 2898]: https://tools.ietf.org/html/rfc2898 [RFC 5246]: https://tools.ietf.org/html/rfc5246 [RFC 5869]: https://tools.ietf.org/html/rfc5869 [RFC 7914]: https://tools.ietf.org/html/rfc7914 [NIST SP 800-132]: https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-132.pdf [NIST SP 800-135 r1]: https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-135r1.pdf