argon2

LuaJIT bindings to the Argon2 hashing function (Argon2d/Argon2i/Argon2id)

$ opm get LoganDark/argon2

luajit-argon2

LuaJIT bindings to the [20171227 version of Argon2]( https://github.com/P-H-C/phc-winner-argon2/blob/670229c849b9fe882583688b74eb7dfdc846f9f6/include/argon2.h), also known as the [Ubuntu argon2 package]( https://packages.ubuntu.com/source/focal/argon2) or libargon2.so.1.

Features

  • binary-safe (embedded nulls allowed) hashing with Argon2i, Argon2d, or Argon2id

  • configuration of all "simple" parameters like iterations, memory usage, parallelism, and salt

  • encoded hashes (includes parameters for easy verification later) as provided by Argon2

  • verification against encoded hashes

Compatibility

This module only works on Linux, with the library libargon2.so.1**. If you are using the Ubuntu argon2 package, then you are good. If not, run this command to verify if your system contains a compatible package (root not required):

    $ ldconfig -p | grep libargon2.so.1

If you get any output, then argon2.lua should be able to find and load Argon2. For example, this means you have the right library installed:

    libargon2.so.1 (libc6,x86-64) => /lib/x86_64-linux-gnu/libargon2.so.1

If you don't, then you will have to find a way to install the library on your system. This varies by distro, so you will have to look it up online.

Usage

Put the argon2.lua file somewhere in your package path (for example, /usr/local/openresty/lualib/argon2.lua for OpenResty) and then simply require it like so:

    local argon2 = require('argon2')

To use the Luanalysis typings (argon2.def.lua), place the file somewhere in your project, and then include a type annotation on the variable holding the argon2 module:

    --- @type argon2
    local argon2 = require('argon2')

Constants

argon2_error_codes

This module re-exports all of Argon2's error codes without the ARGON2_ prefix. Assuming the module is stored in a variable named argon2:

    argon2.OK
    argon2.OUTPUT_PTR_NULL
    argon2.OUTPUT_TOO_SHORT
    argon2.OUTPUT_TOO_LONG
    argon2.PWD_TOO_SHORT
    argon2.PWD_TOO_LONG
    argon2.SALT_TOO_SHORT
    argon2.SALT_TOO_LONG
    argon2.AD_TOO_SHORT
    argon2.AD_TOO_LONG
    argon2.SECRET_TOO_SHORT
    argon2.SECRET_TOO_LONG
    argon2.TIME_TOO_SMALL
    argon2.TIME_TOO_LARGE
    argon2.MEMORY_TOO_LITTLE
    argon2.MEMORY_TOO_MUCH
    argon2.LANES_TOO_FEW
    argon2.LANES_TOO_MANY
    argon2.PWD_PTR_MISMATCH
    argon2.SALT_PTR_MISMATCH
    argon2.SECRET_PTR_MISMATCH
    argon2.AD_PTR_MISMATCH
    argon2.MEMORY_ALLOCATION_ERROR
    argon2.FREE_MEMORY_CBK_NULL
    argon2.ALLOCATE_MEMORY_CBK_NULL
    argon2.INCORRECT_PARAMETER
    argon2.INCORRECT_TYPE
    argon2.OUT_PTR_MISMATCH
    argon2.THREADS_TOO_FEW
    argon2.THREADS_TOO_MANY
    argon2.MISSING_ARGS
    argon2.ENCODING_FAIL
    argon2.DECODING_FAIL
    argon2.THREAD_FAIL
    argon2.DECODING_LENGTH_FAIL
    argon2.VERIFY_MISMATCH

argon2_type

This module re-exports all Argon2 types. Assuming the module is stored in a variable named argon2:

    argon2.argon2d
    argon2.argon2i
    argon2.argon2id

argon2_version

This module re-exports all Argon2 versions. Assuming the module is stored in a variable named argon2:

    argon2.VERSION_10
    argon2.VERSION_13
    argon2.VERSION_NUMBER

Functions

argon2.error_to_string

Syntax: str = argon2.error_to_string(code)

Returns a string for the given code. Returns the raw enum constant minus ARGON2_ - for example, OK or OUTPUT_PTR_NULL. For a human-readable error message, use error_message.

Parameters

  1. code: argon2_error_codes

Returns: string

argon2.error_message

Syntax: str = argon2.error_message(code)

Returns an error message for the given code. Returns what argon2_error_message returns for each error constant.

Parameters

  1. code: argon2_error_codes

Returns: string

argon2.type_to_string

Syntax: str = argon2.type_to_string(type, uppercase)

Returns a string for the given type. This is done by calling argon2_type2string.

Parameters

  1. type: argon2_type

  2. uppercase: boolean | nil

Returns: string

argon2.hash

Syntax: hash, err = argon2.hash(iterations, memory_kb, parallelism, password, salt, hash_len, type, version)

Hashes the given password with the provided salt and produces hash_len bytes of output. If the hash fails, then nil and an error code will be returned.

Parameters

  1. iterations: number

    The number of iterations to perform. A higher iteration count increases the time/computational cost of the algorithm. This should be tuned so that brute force becomes infeasible without hashing becoming so expensive that it brings down your application.

  1. memory_kb: number

    The amount of memory (in kilobytes) to use for the algorithm.

  1. parallelism: number

    The amount of parallelism (threads and compute lanes) to use for the algorithm. This changes the output.

  1. password: string

    The password to hash. Embedded zeroes and binary data are allowed.

  1. salt: string

    The salt to use. This must be at least 8 bytes and should be random.

  1. hash_len: number

    The desired hash length in bytes. Longer hashes reduce the chance of collisions but require more storage.

  1. type: argon2_type

    The argon2 algorithm to use. Argon2d is potentially vulnerable to side-channel attacks, Argon2i is not. Argon2id combines both and should be used if you're unsure.

  1. version: argon2_version

    The version of argon2 to use. Generally, you should use VERSION_NUMBER for the latest version only if you are using encoded hashes. Otherwise, to prevent silent breakages, choose a stable version to use for your hashes, or make sure to keep track of it separately.

Returns: string | nil, argon2_error_codes

argon2.encoded_len

Syntax: encoded_len = argon2.encoded_len(iterations, memory_kb, parallelism, salt_len, hash_len, type)

Returns the number of bytes that an encoded hash with the given parameters, salt and hash length, and type would require. Does not include a null terminator.

This is typically unnecessary, as Lua strings are variable-length, but there may be scenarios in which you would need to know the size of an encoded hash before actually performing the work. For example, hash_encoded uses this function internally to allocate a perfectly-sized buffer.

In such cases, however, you would likely want to use the argon2 C functions directly.

Parameters

  1. iterations: number

  2. memory_kb: number

  3. parallelism: number

  4. salt_len: number

  5. hash_len: number

  6. type: argon2_type

Returns: number

argon2.hash_encoded

Syntax: encoded, err = argon2.hash_encoded(iterations, memory_kb, parallelism, password, salt, hash_len, type, version)

Hashes the given password with the given parameters and salt and produces an encoded hash encapsulating hash_len bytes of output plus all the parameters used for the hash. If the hash fails, then nil and an error code will be returned.

The produced output is variable-length because it includes the parameters as plain text.

Encoded hashes look like this:

    > argon2.hash_encoded(10000, 64, 1, 'hi', 'thisisasalt', 16, argon2.argon2id, argon2.VERSION_NUMBER)
    $argon2id$v=19$m=64,t=10000,p=1$dGhpc2lzYXNhbHQ$TwT+k2qa1WWoQFc4ccF9yw

Since encoded hashes include all information required to reproduce the hash parameters, verify_encoded only needs the password (and type) to check if the given password matches the encoded hash. Additionally, high-risk accounts (i.e. administrators) can be given more expensive hashes (more iterations, memory or parallelism) to make them even more difficult to crack.

Parameters

The full descriptions of all parameters are under argon2.hash.

  1. iterations: number

  2. memory_kb: number

  3. parallelism: number

  4. password: string

  5. salt: string

  6. hash_len: number

  7. type: argon2_type

  8. version: argon2_version

Returns: string | nil, argon2_error_codes

argon2.verify_encoded

Syntax: matches, err = argon2.verify_encoded(encoded, password, type)

Verifies the given password against an encoded hash of the specified type. This function returns true if the password matches the hash, or false and an error code otherwise.

Typically the error code will be VERIFY_MISMATCH if the password simply does not match.

Parameters

  1. encoded: string

  2. password: string

  3. type: argon2_type

Returns: true | false, argon2_error_codes

License

MIT License

Copyright (c) 2022 LoganDark

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

POD ERRORS

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Around line 46:

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Authors

LoganDark

License

mit

Dependencies

luajit

Versions