FFI-based OpenSSL binding for LuaJIT, supporting OpenSSL 3.0, 1.1 and 1.0.2 series.
BoringSSL is also supported.
- Description
- Status
- Synopsis
- resty.openssl
- resty.openssl.version
- resty.openssl.provider
- resty.openssl.pkey
- resty.openssl.bn
- bn.new
- bn.dup
- bn.istype
- bn.from_binary, bn:to_binary
- bn.from_hex, bn:to_hex
- bn.from_dec, bn:to_dec
- bn:to_number
- bn:__metamethods
- bn:add, bn:sub, bn:mul, bn:div, bn:exp, bn:mod, bn:gcd
- bn:sqr
- bn:mod_add, bn:mod_sub, bn:mod_mul, bn:mod_exp
- bn:mod_sqr
- bn:lshift, bn:rshift
- bn:is_zero, bn:is_one, bn:is_odd, bn:is_word
- bn:is_prime
- resty.openssl.cipher
- resty.openssl.digest
- resty.openssl.hmac
- resty.openssl.kdf
- resty.openssl.objects
- resty.openssl.pkcs12
- resty.openssl.rand
- resty.openssl.x509
- x509.new
- x509.dup
- x509.istype
- x509:digest
- x509:pubkey_digest
- x509:check_private_key
- x509:get_, x509:set_
- x509:get_lifetime
- x509:set_lifetime
- x509:get_signature_name, x509:get_signature_nid
- x509:get_extension
- x509:add_extension
- x509:set_extension
- x509:get_extension_critical
- x509:set_extension_critical
- x509:get_ocsp_url
- x509:get_crl_url
- x509:sign
- x509:verify
- x509:tostring
- x509:to_PEM
- resty.openssl.x509.csr
- resty.openssl.x509.crl
- resty.openssl.x509.name
- resty.openssl.x509.altname
- resty.openssl.x509.extension
- resty.openssl.x509.extension.dist_points
- resty.openssl.x509.extension.info_access
- resty.openssl.x509.extensions
- resty.openssl.x509.chain
- resty.openssl.x509.store
- resty.openssl.x509.revoked
- resty.openssl.ssl
- resty.openssl.ssl_ctx
- Functions for stack-like objects
- General rules on garbage collection
- Code generation
- Compatibility
- Credits
- Copyright and License
- See Also
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
.
Production.
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).
BoringSSL removes some algorithms and not all functionalities below is supported by BoringSSL. Please consul its manual for differences between OpenSSL API.
This meta module provides a version sanity check against linked OpenSSL library.
syntax: openssl.load_modules()
Load all available sub modules into current module:
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"),
ssl = require("resty.openssl.ssl"),
ssl_ctx = require("resty.openssl.ssl_ctx"),
Starting OpenSSL 3.0, provider
is also available.
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.
syntax: enabled = openssl.get_fips_mode()
Returns a boolean indicating if FIPS mode is enabled.
syntax: ok, err = openssl.set_fips_mode(enabled)
Toggle FIPS mode on or off.
A module to provide version info.
The OpenSSL version number.
The OpenSSL version text.
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"
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"
A boolean indicates whether the linked OpenSSL is 3.0 series.
A boolean indicates whether the linked OpenSSL is 1.1 series.
A boolean indicates whether the linked OpenSSL is 1.0 series.
Module to interact with providers. This module only work on OpenSSL >= 3.0.0.
syntax: pro, err = provider.load(name, try?)
Load provider with name
. If try
is set to true, OpenSSL will not disable the
fall-back providers if the provider cannot be loaded and initialized. If the provider
loads successfully, however, the fall-back providers are disabled.
For now this functions loads provider into the default context, meaning it will affect other applications in the same process using the default context as well.
syntax: ok = pkey.provider(table)
Returns true
if table is an instance of provider
. Returns false
otherwise.
syntax: ok, err = provider.is_available(name)
Checks if a named provider is available for use.
syntax: ok, err = provider.set_default_search_path(name)
Specifies the default search path that is to be used for looking for providers.
syntax: ok, err = pro:unload(name)
Unload a provider that is previously loaded by provider.load
.
syntax: ok, err = pro:self_test(name)
Runs a provider's self tests on demand. If the self tests fail then the provider will fail to provide any further services and algorithms.
syntax: ok, err = pro:get_params(key1, key2?...)
Returns one or more provider parameter values.
local pro = require "resty.openssl.provider"
local p = pro.load("default")
local name = assert(p:get_params("name"))
print(name)
-- outputs "OpenSSL Default Provider"
local result = assert(p:get_params("name", "version", "buildinfo", "status"))
print(require("cjson").encode(result))
-- outputs '{"buildinfo":"3.0.0-alpha7","name":"OpenSSL Default Provider","status":1,"version":"3.0.0"}'
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.
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.
- 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 type
s are Ed25519
, X25519
, Ed448
and X448
. No additional parameters
can be set during key generation for those keys.
- Pass a
string
of private or public key in PEM, DER or JWK format text; optionally accpet a tableopts
to explictly loadformat
and keytype
. When loading a key in PEM format,passphrase
orpassphrase_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
andP-512
EC
,Ed25519
,X25519
,Ed448
andX448
OKP
keys are supported. - Public key part for
OKP
keys (thex
parameter) is always not honored and derived from private key part (thed
parameter) if it's specified.
- Pass
nil
to create a 2048 bits RSA key. - Pass a
EVP_PKEY*
pointer, to return a wrappedpkey
instance. Normally user won't use this approach. User shouldn't free the pointer on their own, since the pointer is not copied.
syntax: ok = pkey.istype(table)
Returns true
if table is an instance of pkey
. Returns false
otherwise.
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',
})
syntax: parameters, err = pk:get_parameters()
Returns a table containing the parameters
of pkey instance.
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 |
syntax: ok = pk:is_private()
Checks whether pk
is a private key. Returns true if it's a private key, returns false if
it's a public key.
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"}'
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 signing and requires
digest
to be a string. 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))
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))
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
.
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 "🦢"
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.
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.
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.
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.
syntax: pem, err = pk:to_PEM(private_or_public?)
Equivalent to pkey:tostring(private_or_public, "PEM")
.
Module to expose BIGNUM structure. Note bignum is a big integer, no float operations (like square root) are supported.
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.
syntax: b, err = bn.dup(bn_ptr_cdata)
Duplicates a BIGNUM*
to create a new bn
instance.
syntax: ok = bn.istype(table)
Returns true
if table is an instance of bn
. Returns false
otherwise.
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="
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"
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"
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"
syntax: bn, err = bn.generate_prime(bits, safe)
Generates a pseudo-random prime number of bit length bits
.
If safe
is true, it will be a safe prime (i.e. a prime p so that (p-1)/2 is also prime).
The PRNG must be seeded prior to calling BN_generate_prime_ex(). The prime number generation has a negligible error probability.
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
syntax: r = a:op(b)
syntax: r = bn.op(a, b)
Perform mathematical operations op
.
add
: addsub
: subtractmul
: multiplydiv
,idiv
: floor division (division with rounding down to nearest integer)exp
,pow
: theb
-th power ofa
, this function is faster than repeateda * a * ...
.mod
: modulogcd
: the greatest common divider ofa
andb
.
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)
syntax: r = a:sqr()
syntax: r = bn.sqr(a)
Computes the 2-th power of a
. This function is faster than r = a * a
.
syntax: r = a:op(b, m)
syntax: r = bn.op(a, b, m)
Perform modulo mathematical operations op
.
mod_add
: addsa
tob
modulom
mod_sub
: substractsb
froma
modulom
mod_mul
: multipliesa
byb
and finds the non-negative remainder respective to modulusm
mod_exp
,mod_pow
: computesa
to theb
-th power modulom
(r=a^b % m). This function uses less time and space thanexp
. Do not call this function whenm
is even and any of the parameters have theBN_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)
syntax: r = a:mod_sqr(m)
syntax: r = bn.mod_sqr(a, m)
Takes the square of a
modulo m
.
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.
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.
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).
Module to interact with symmetric cryptography (EVP_CIPHER).
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
.
syntax: ok = cipher.istype(table)
Returns true
if table is an instance of cipher
. Returns false
otherwise.
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
.
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
.
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.
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.
syntax: ok, err = cipher:update_aead_aad(aad)
Provides AAD data to the cipher, this function can be called more than one times.
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.
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.
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.
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`
Module to interact with message digest (EVP_MD_CTX).
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.
syntax: ok = digest.istype(table)
Returns true
if table is an instance of digest
. Returns false
otherwise.
syntax: ok, err = digest:update(partial, ...)
Updates the digest with one or more strings.
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="
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.
Module to interact with hash-based message authentication code (HMAC_CTX).
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
.
syntax: ok = hmac.istype(table)
Returns true
if table is an instance of hmac
. Returns false
otherwise.
syntax: ok, err = hmac:update(partial, ...)
Updates the HMAC with one or more strings.
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="
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.
Module to interact with KDF (key derivation function).
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) andscrypt
(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=="
Helpfer module on ASN1_OBJECT.
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,
}
syntax: tbl, err = objects.nid2table(nid)
Convert a NID to a Lua table, returns the same format as objects.obj2table
syntax: nid, err = objects.txt2nid(txt)
Convert a text representation to NID.
Module to interact with PKCS#12 format.
syntax: der, err = pkcs12.encode(data, passphrase?)
Encode data in data
to a PKCS#12 text.
data
is a table that contains:
Key | Type | Description | Required or default |
---|---|---|---|
key | pkey | Private key | required |
cert | x509 | Certificate | required |
cacerts | A list of x509 as Lua table | Additional certificates | [] |
friendly_name | string | The name used for the supplied certificate and key | "" |
nid_key | number or string | The NID or text to specify algorithm to encrypt key | "PBE-SHA1-RC2-4" if compiled with RC2, otherwise "PBE-SHA1-3DES" |
nid_cert | number or string | The NID or text to specify algorithm to encrypt cert | "PBE-SHA1-3DES" |
iter | number | Key iterration count | PKCS12_DEFAULT_ITER (2048) |
mac_iter | number | MAC iterration count | 1 |
passphrase
is the string for encryption. If omitted, an empty string will be used.
Note in OpenSSL 3.0 RC2
has been moved to legacy provider. In order to encode p12 data with RC2
encryption, you need to load the legacy provider first.
local pro = require "resty.openssl.provider"
local legacy_provider = assert(pro.load("legacy"))
local p12, err = pkcs12.encode({ key = key, cert = cert})
assert(legacy_provider:unload())
syntax: data, err = pkcs12.decode(p12, passphrase?)
Decode a PKCS#12 text to Lua table data
. Similar to the data
table passed to pkcs12.encode,
but onle cert
, key
, cacerts
and friendly_name
are returned.
passphrase
is the string for encryption. If omitted, an empty string will be used.
Note in OpenSSL 3.0 RC2
has been moved to legacy provider. In order to decode p12 data with RC2
encryption, you need to load the legacy provider first.
Module to interact with random number generator.
syntax: str, err = rand.bytes(length)
Generate random bytes with length of length
.
Module to interact with X.509 certificates.
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.
syntax: x509, err = x509.dup(x509_ptr_cdata)
Duplicates a X509*
to create a new x509
instance.
syntax: ok = x509.istype(table)
Returns true
if table is an instance of x509
. Returns false
otherwise.
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
.
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
.
syntax: match, err = x509:check_private_key(pkey)
Checks the consistency of private key pkey
with the public key in current X509 object.
Returns a boolean indicating if it's a match and err describing the reason.
Note this function also checks if k itself is indeed a private key or not.
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
syntax: not_before, not_after, err = x509:get_lifetime()
A shortcut of x509:get_not_before
plus x509:get_not_after
syntax: ok, err = x509:set_lifetime(not_before, not_after)
A shortcut of x509:set_not_before
plus x509:set_not_after
.
syntax: sn, err = x509:get_signature_name()
syntax: nid, err = x509:get_signature_nid()
Return the NID or the short name (SN) of the signature of the certificate.
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"
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)
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.
syntax: ok, err = x509:get_extension_critical(nid_or_txt)
Get critical flag of the X.509 extension
matching the given NID from certificate.
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.
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.
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.
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.
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.
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.
syntax: pem, err = x509:to_PEM()
Outputs the certificate in PEM-formatted text.
Module to interact with certificate signing request (X509_REQ).
See examples/csr.lua for an example to generate CSR.
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.
syntax: ok = csr.istype(table)
Returns true
if table is an instance of csr
. Returns false
otherwise.
syntax: match, err = csr:check_private_key(pkey)
Checks the consistency of private key pkey
with the public key in current CSR object.
Returns a boolean indicating if it's a match and err describing the reason.
Note this function also checks if k itself is indeed a private key or not.
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
Same as csr:set_subject_alt_name, this function is deprecated to align with naming convension with other functions.
syntax: sn, err = csr:get_signature_name()
syntax: nid, err = csr:get_signature_nid()
Return the NID or the short name (SN) of the signature of the certificate request.
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")
syntax: extensions, err = csr:get_extensions()
Return all extensions as a resty.openssl.x509.extensions instance.
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.
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.
syntax: ok, err = csr:get_extension_critical(nid_or_txt)
Get critical flag of the X.509 extension
matching the given NID from csr.
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.
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.
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.
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.
syntax: pem, err = csr:to_PEM(?)
Outputs CSR in PEM-formatted text.
Module to interact with X509_CRL(certificate revocation list).
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.
syntax: crl, err = crl.dup(crl_ptr_cdata)
Duplicates a X509_CRL*
to create a new crl
instance.
syntax: ok = crl.istype(table)
Returns true
if table is an instance of crl
. Returns false
otherwise.
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
syntax: sn, err = crl:get_signature_name()
syntax: nid, err = crl:get_signature_nid()
Return the NID or the short name (SN) of the signature of the CRL.
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.
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.
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.
syntax: ok, err = crl:get_extension_critical(nid_or_txt)
Get critical flag of the X.509 extension
matching the given NID from CRL.
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.
syntax: ok, err = crl:add_revoked(revoked)
Adds a resty.openssl.x509.revoked instance to the CRL.
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.
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.
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.
syntax: pem, err = crl:to_PEM()
Outputs the CRL in PEM-formatted text.
Module to interact with X.509 names.
syntax: name, err = name.new()
Creates an empty name
instance.
syntax: name, err = name.dup(name_ptr_cdata)
Duplicates a X509_NAME*
to create a new name
instance.
syntax: ok = name.istype(table)
Returns true
if table is an instance of name
. Returns false
otherwise.
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")
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"
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"
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"}'
Module to interact with GENERAL_NAMES, an extension to X.509 names.
syntax: altname, err = altname.new()
Creates an empty altname
instance.
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.
syntax: altname = digest.istype(table)
Returns true
if table is an instance of altname
. Returns false
otherwise.
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
This function can be called multiple times in a chained fashion.
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"
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.
Only the following types are decoded, other types are decoded as "TYPE:<unsupported>"
:
RFC822Name / Email
URI
DNS
DirName
Module to interact with X.509 extensions.
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.
Example usages:
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
})
See examples/tls-alpn-01.lua for an example to create extension with an unknown nid.
syntax: ext, err = extension.dup(extension_ptr_cdata)
Creates a new extension
instance from X509_EXTENSION*
pointer.
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.
syntax: ext, ok = extension.from_data(table, nid_or_txt, crit?)
Creates a new extension
instance. table
can be instance of:
nid_or_txt
is a number or text representation of NID and
crit
is the critical flag of the extension.
syntax: ok = extension.istype(table)
Returns true
if table is an instance of extension
. Returns false
otherwise.
syntax: crit, err = extension:get_extension_critical()
Returns true
if extension is critical. Returns false
otherwise.
syntax: ok, err = extension:set_extension_critical(crit)
Set the critical flag of the extension.
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.
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"
syntax: txt, err = extension:tostring()
Same as extension:text.
Module to interact with CRL Distribution Points(DIST_POINT stack).
syntax: dp, err = dist_points.new()
Creates a new dist_points
instance.
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.
syntax: ok = dist_points.istype(table)
Returns true
if table is an instance of dist_points
. Returns false
otherwise.
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
Module to interact with Authority Information Access data (AUTHORITY_INFO_ACCESS, ACCESS_DESCRIPTION stack).
syntax: aia, err = info_access.new()
Creates a new info_access
instance.
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.
syntax: ok = info_access.istype(table)
Returns true
if table is an instance of info_access
. Returns false
otherwise.
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.
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
Module to interact with X.509 Extension stack.
syntax: ch, err = extensions.new()
Creates a new extensions
instance.
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.
syntax: ok = extensions.istype(table)
Returns true
if table is an instance of extensions
. Returns false
otherwise.
syntax: ok, err = extensions:add(x509)
Add a x509
object to the extensions. The first argument must be a
resty.openssl.x509 instance.
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.
Module to interact with X.509 stack.
syntax: ch, err = chain.new()
Creates a new chain
instance.
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.
syntax: ok = chain.istype(table)
Returns true
if table is an instance of chain
. Returns false
otherwise.
syntax: ok, err = chain:add(x509)
Add a x509
object to the chain. The first argument must be a
resty.openssl.x509 instance.
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.
Module to interact with X.509 certificate store (X509_STORE).
syntax: st, err = store.new()
Creates a new store
instance.
syntax: ok = store.istype(table)
Returns true
if table is an instance of store
. Returns false
otherwise.
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
.
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.
syntax: ok, err = store:load_file(path)
Loads a X.509 certificate on file system into store.
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).
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.
Module to interact with X509_REVOKED.
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.
syntax: ok = revoked.istype(table)
Returns true
if table is an instance of revoked
. Returns false
otherwise.
Module to interact with SSL connection.
This module is currently considered experimental.
Note: to use this module in production, user is encouraged to compile lua-resty-openssl-aux-module.
syntax: sess, err = ssl.from_request()
Wraps the SSL*
instance from current downstream request.
syntax: sess, err = ssl.from_socket(sock)
Wraps the SSL*
instance from a TCP cosocket, the cosocket must have already
been called sslhandshake
.
syntax: x509, err = ssl:get_peer_certificate()
Return the peer certificate as a x509 instance. Depending on the type
of ssl
, peer certificate means the server certificate on client side, or the client certificate
on server side.
syntax: chain, err = ssl:get_peer_certificate()
Return the whole peer certificate chain as a x509.chain instance.
Depending on the type of ssl
, peer certificate means the server certificate on client side,
or the client certificate on server side.
Module to interact with SSL_CTX context.
This module is currently considered experimental.
Note: to use this module in production, user is encouraged to compile lua-resty-openssl-aux-module.
syntax: ctx, err = ssl_ctx.from_request()
Wraps the SSL_CTX*
instance from current downstream request.
syntax: sess, err = ssl_ctx.from_socket(sock)
Wraps the SSL_CTX*
instance from a TCP cosocket, the cosocket must have already
been called sslhandshake
.
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"}'
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
syntax: objs, err = x:all()
Returns all objects in the table. Use this while LUAJIT_ENABLE_LUA52COMPAT
is not enabled.
syntax: len = x:count()
Returns count of objects of the table. Use this while LUAJIT_ENABLE_LUA52COMPAT
is not enabled.
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.
- 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- 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.
- If it's created by
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
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.
This project receives contribution from following developers:
This module is licensed under the BSD license.
Copyright (C) 2019-2020, by fffonion [email protected].
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.