nim-libp2p-experimental/libp2p/crypto/crypto.nim

1069 lines
34 KiB
Nim

# Nim-Libp2p
# Copyright (c) 2023 Status Research & Development GmbH
# Licensed under either of
# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
# * MIT license ([LICENSE-MIT](LICENSE-MIT))
# at your option.
# This file may not be copied, modified, or distributed except according to
# those terms.
## This module implements Public Key and Private Key interface for libp2p.
{.push raises: [].}
from strutils import split, strip, cmpIgnoreCase
const libp2p_pki_schemes* {.strdefine.} = "rsa,ed25519,secp256k1,ecnist"
type
PKScheme* = enum
RSA = 0,
Ed25519,
Secp256k1,
ECDSA
proc initSupportedSchemes(list: static string): set[PKScheme] =
var res: set[PKScheme]
let schemes = split(list, {',', ';', '|'})
for item in schemes:
if cmpIgnoreCase(strip(item), "rsa") == 0:
res.incl(PKScheme.RSA)
elif cmpIgnoreCase(strip(item), "ed25519") == 0:
res.incl(PKScheme.Ed25519)
elif cmpIgnoreCase(strip(item), "secp256k1") == 0:
res.incl(PKScheme.Secp256k1)
elif cmpIgnoreCase(strip(item), "ecnist") == 0:
res.incl(PKScheme.ECDSA)
if len(res) == 0:
res = {PKScheme.RSA, PKScheme.Ed25519, PKScheme.Secp256k1, PKScheme.ECDSA}
res
proc initSupportedSchemes(schemes: static set[PKScheme]): set[int8] =
var res: set[int8]
if PKScheme.RSA in schemes:
res.incl(int8(PKScheme.RSA))
if PKScheme.Ed25519 in schemes:
res.incl(int8(PKScheme.Ed25519))
if PKScheme.Secp256k1 in schemes:
res.incl(int8(PKScheme.Secp256k1))
if PKScheme.ECDSA in schemes:
res.incl(int8(PKScheme.ECDSA))
res
const
SupportedSchemes* = initSupportedSchemes(libp2p_pki_schemes)
SupportedSchemesInt* = initSupportedSchemes(SupportedSchemes)
RsaDefaultKeySize* = 3072
template supported*(scheme: PKScheme): bool =
## Returns true if specified ``scheme`` is currently available.
scheme in SupportedSchemes
when supported(PKScheme.RSA):
import rsa
when supported(PKScheme.Ed25519):
import ed25519/ed25519
when supported(PKScheme.Secp256k1):
import secp
# We are still importing `ecnist` because, it is used for SECIO handshake,
# but it will be impossible to create ECNIST keys or import ECNIST keys.
import ecnist, bearssl/rand, bearssl/hash as bhash
import ../protobuf/minprotobuf, ../vbuffer, ../multihash, ../multicodec
import nimcrypto/[rijndael, twofish, sha2, hash, hmac]
# We use `ncrutils` for constant-time hexadecimal encoding/decoding procedures.
import nimcrypto/utils as ncrutils
import ../utility
import stew/results
export results, utility
# This is workaround for Nim's `import` bug
export rijndael, twofish, sha2, hash, hmac, ncrutils, rand
type
DigestSheme* = enum
Sha256,
Sha512
ECDHEScheme* = EcCurveKind
PublicKey* = object
case scheme*: PKScheme
of PKScheme.RSA:
when PKScheme.RSA in SupportedSchemes:
rsakey*: rsa.RsaPublicKey
else:
discard
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
edkey*: EdPublicKey
else:
discard
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
skkey*: SkPublicKey
else:
discard
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
eckey*: ecnist.EcPublicKey
else:
discard
PrivateKey* = object
case scheme*: PKScheme
of PKScheme.RSA:
when supported(PKScheme.RSA):
rsakey*: rsa.RsaPrivateKey
else:
discard
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
edkey*: EdPrivateKey
else:
discard
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
skkey*: SkPrivateKey
else:
discard
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
eckey*: ecnist.EcPrivateKey
else:
discard
KeyPair* = object
seckey*: PrivateKey
pubkey*: PublicKey
Secret* = object
ivsize*: int
keysize*: int
macsize*: int
data*: seq[byte]
Signature* = object
data*: seq[byte]
CryptoError* = enum
KeyError,
SigError,
HashError,
SchemeError
CryptoResult*[T] = Result[T, CryptoError]
template orError*(exp: untyped, err: untyped): untyped =
(exp.mapErr do (_: auto) -> auto: err)
proc newRng*(): ref HmacDrbgContext =
# You should only create one instance of the RNG per application / library
# Ref is used so that it can be shared between components
# TODO consider moving to bearssl
var seeder = prngSeederSystem(nil)
if seeder == nil:
return nil
var rng = (ref HmacDrbgContext)()
hmacDrbgInit(rng[], addr sha256Vtable, nil, 0)
if seeder(addr rng.vtable) == 0:
return nil
rng
proc shuffle*[T](
rng: ref HmacDrbgContext,
x: var openArray[T]) =
if x.len == 0: return
var randValues = newSeqUninitialized[byte](len(x) * 2)
hmacDrbgGenerate(rng[], randValues)
for i in countdown(x.high, 1):
let
rand = randValues[i * 2].int32 or (randValues[i * 2 + 1].int32 shl 8)
y = rand mod i
swap(x[i], x[y])
proc random*(T: typedesc[PrivateKey], scheme: PKScheme,
rng: var HmacDrbgContext,
bits = RsaDefaultKeySize): CryptoResult[PrivateKey] =
## Generate random private key for scheme ``scheme``.
##
## ``bits`` is number of bits for RSA key, ``bits`` value must be in
## [2048, 4096], default value is 3072 bits.
case scheme
of PKScheme.RSA:
when supported(PKScheme.RSA):
let rsakey = ? RsaPrivateKey.random(rng, bits).orError(KeyError)
ok(PrivateKey(scheme: scheme, rsakey: rsakey))
else:
err(SchemeError)
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
let edkey = EdPrivateKey.random(rng)
ok(PrivateKey(scheme: scheme, edkey: edkey))
else:
err(SchemeError)
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
let eckey = ? ecnist.EcPrivateKey.random(Secp256r1, rng).orError(KeyError)
ok(PrivateKey(scheme: scheme, eckey: eckey))
else:
err(SchemeError)
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
let skkey = SkPrivateKey.random(rng)
ok(PrivateKey(scheme: scheme, skkey: skkey))
else:
err(SchemeError)
proc random*(T: typedesc[PrivateKey], rng: var HmacDrbgContext,
bits = RsaDefaultKeySize): CryptoResult[PrivateKey] =
## Generate random private key using default public-key cryptography scheme.
##
## Default public-key cryptography schemes are following order:
## ed25519, secp256k1, RSA, secp256r1.
##
## So will be used first available (supported) method.
when supported(PKScheme.Ed25519):
let edkey = EdPrivateKey.random(rng)
ok(PrivateKey(scheme: PKScheme.Ed25519, edkey: edkey))
elif supported(PKScheme.Secp256k1):
let skkey = SkPrivateKey.random(rng)
ok(PrivateKey(scheme: PKScheme.Secp256k1, skkey: skkey))
elif supported(PKScheme.RSA):
let rsakey = ? RsaPrivateKey.random(rng, bits).orError(KeyError)
ok(PrivateKey(scheme: PKScheme.RSA, rsakey: rsakey))
elif supported(PKScheme.ECDSA):
let eckey = ? ecnist.EcPrivateKey.random(Secp256r1, rng).orError(KeyError)
ok(PrivateKey(scheme: PKScheme.ECDSA, eckey: eckey))
else:
err(SchemeError)
proc random*(T: typedesc[KeyPair], scheme: PKScheme,
rng: var HmacDrbgContext,
bits = RsaDefaultKeySize): CryptoResult[KeyPair] =
## Generate random key pair for scheme ``scheme``.
##
## ``bits`` is number of bits for RSA key, ``bits`` value must be in
## [512, 4096], default value is 2048 bits.
case scheme
of PKScheme.RSA:
when supported(PKScheme.RSA):
let pair = ? RsaKeyPair.random(rng, bits).orError(KeyError)
ok(KeyPair(
seckey: PrivateKey(scheme: scheme, rsakey: pair.seckey),
pubkey: PublicKey(scheme: scheme, rsakey: pair.pubkey)))
else:
err(SchemeError)
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
let pair = EdKeyPair.random(rng)
ok(KeyPair(
seckey: PrivateKey(scheme: scheme, edkey: pair.seckey),
pubkey: PublicKey(scheme: scheme, edkey: pair.pubkey)))
else:
err(SchemeError)
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
let pair = ? EcKeyPair.random(Secp256r1, rng).orError(KeyError)
ok(KeyPair(
seckey: PrivateKey(scheme: scheme, eckey: pair.seckey),
pubkey: PublicKey(scheme: scheme, eckey: pair.pubkey)))
else:
err(SchemeError)
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
let pair = SkKeyPair.random(rng)
ok(KeyPair(
seckey: PrivateKey(scheme: scheme, skkey: pair.seckey),
pubkey: PublicKey(scheme: scheme, skkey: pair.pubkey)))
else:
err(SchemeError)
proc random*(T: typedesc[KeyPair], rng: var HmacDrbgContext,
bits = RsaDefaultKeySize): CryptoResult[KeyPair] =
## Generate random private pair of keys using default public-key cryptography
## scheme.
##
## Default public-key cryptography schemes are following order:
## ed25519, secp256k1, RSA, secp256r1.
##
## So will be used first available (supported) method.
when supported(PKScheme.Ed25519):
let pair = EdKeyPair.random(rng)
ok(KeyPair(
seckey: PrivateKey(scheme: PKScheme.Ed25519, edkey: pair.seckey),
pubkey: PublicKey(scheme: PKScheme.Ed25519, edkey: pair.pubkey)))
elif supported(PKScheme.Secp256k1):
let pair = SkKeyPair.random(rng)
ok(KeyPair(
seckey: PrivateKey(scheme: PKScheme.Secp256k1, skkey: pair.seckey),
pubkey: PublicKey(scheme: PKScheme.Secp256k1, skkey: pair.pubkey)))
elif supported(PKScheme.RSA):
let pair = ? RsaKeyPair.random(rng, bits).orError(KeyError)
ok(KeyPair(
seckey: PrivateKey(scheme: PKScheme.RSA, rsakey: pair.seckey),
pubkey: PublicKey(scheme: PKScheme.RSA, rsakey: pair.pubkey)))
elif supported(PKScheme.ECDSA):
let pair = ? EcKeyPair.random(Secp256r1, rng).orError(KeyError)
ok(KeyPair(
seckey: PrivateKey(scheme: PKScheme.ECDSA, eckey: pair.seckey),
pubkey: PublicKey(scheme: PKScheme.ECDSA, eckey: pair.pubkey)))
else:
err(SchemeError)
proc getPublicKey*(key: PrivateKey): CryptoResult[PublicKey] =
## Get public key from corresponding private key ``key``.
case key.scheme
of PKScheme.RSA:
when supported(PKScheme.RSA):
let rsakey = key.rsakey.getPublicKey()
ok(PublicKey(scheme: RSA, rsakey: rsakey))
else:
err(SchemeError)
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
let edkey = key.edkey.getPublicKey()
ok(PublicKey(scheme: Ed25519, edkey: edkey))
else:
err(SchemeError)
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
let eckey = ? key.eckey.getPublicKey().orError(KeyError)
ok(PublicKey(scheme: ECDSA, eckey: eckey))
else:
err(SchemeError)
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
let skkey = key.skkey.getPublicKey()
ok(PublicKey(scheme: Secp256k1, skkey: skkey))
else:
err(SchemeError)
proc toRawBytes*(key: PrivateKey | PublicKey,
data: var openArray[byte]): CryptoResult[int] =
## Serialize private key ``key`` (using scheme's own serialization) and store
## it to ``data``.
##
## Returns number of bytes (octets) needed to store private key ``key``.
case key.scheme
of PKScheme.RSA:
when supported(PKScheme.RSA):
key.rsakey.toBytes(data).orError(KeyError)
else:
err(SchemeError)
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
ok(key.edkey.toBytes(data))
else:
err(SchemeError)
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
key.eckey.toBytes(data).orError(KeyError)
else:
err(SchemeError)
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
key.skkey.toBytes(data).orError(KeyError)
else:
err(SchemeError)
proc getRawBytes*(key: PrivateKey | PublicKey): CryptoResult[seq[byte]] =
## Return private key ``key`` in binary form (using scheme's own
## serialization).
case key.scheme
of PKScheme.RSA:
when supported(PKScheme.RSA):
key.rsakey.getBytes().orError(KeyError)
else:
err(SchemeError)
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
ok(key.edkey.getBytes())
else:
err(SchemeError)
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
key.eckey.getBytes().orError(KeyError)
else:
err(SchemeError)
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
ok(key.skkey.getBytes())
else:
err(SchemeError)
proc toBytes*(key: PrivateKey, data: var openArray[byte]): CryptoResult[int] =
## Serialize private key ``key`` (using libp2p protobuf scheme) and store
## it to ``data``.
##
## Returns number of bytes (octets) needed to store private key ``key``.
var msg = initProtoBuffer()
msg.write(1, uint64(key.scheme))
msg.write(2, ? key.getRawBytes())
msg.finish()
var blen = len(msg.buffer)
if len(data) >= blen:
copyMem(addr data[0], addr msg.buffer[0], blen)
ok(blen)
proc toBytes*(key: PublicKey, data: var openArray[byte]): CryptoResult[int] =
## Serialize public key ``key`` (using libp2p protobuf scheme) and store
## it to ``data``.
##
## Returns number of bytes (octets) needed to store public key ``key``.
var msg = initProtoBuffer()
msg.write(1, uint64(key.scheme))
msg.write(2, ? key.getRawBytes())
msg.finish()
var blen = len(msg.buffer)
if len(data) >= blen and blen > 0:
copyMem(addr data[0], addr msg.buffer[0], blen)
ok(blen)
proc toBytes*(sig: Signature, data: var openArray[byte]): int =
## Serialize signature ``sig`` and store it to ``data``.
##
## Returns number of bytes (octets) needed to store signature ``sig``.
result = len(sig.data)
if len(data) >= result and result > 0:
copyMem(addr data[0], unsafeAddr sig.data[0], len(sig.data))
proc getBytes*(key: PrivateKey): CryptoResult[seq[byte]] =
## Return private key ``key`` in binary form (using libp2p's protobuf
## serialization).
var msg = initProtoBuffer()
msg.write(1, uint64(key.scheme))
msg.write(2, ? key.getRawBytes())
msg.finish()
ok(msg.buffer)
proc getBytes*(key: PublicKey): CryptoResult[seq[byte]] =
## Return public key ``key`` in binary form (using libp2p's protobuf
## serialization).
var msg = initProtoBuffer()
msg.write(1, uint64(key.scheme))
msg.write(2, ? key.getRawBytes())
msg.finish()
ok(msg.buffer)
proc getBytes*(sig: Signature): seq[byte] =
## Return signature ``sig`` in binary form.
result = sig.data
template initImpl[T: PrivateKey|PublicKey](
key: var T, data: openArray[byte]): bool =
## Initialize private key ``key`` from libp2p's protobuf serialized raw
## binary form.
##
## Returns ``true`` on success.
var id: uint64
var buffer: seq[byte]
if len(data) <= 0:
false
else:
var pb = initProtoBuffer(@data)
let r1 = pb.getField(1, id)
let r2 = pb.getField(2, buffer)
if not(r1.get(false) and r2.get(false)):
false
else:
if cast[int8](id) notin SupportedSchemesInt or len(buffer) <= 0:
false
else:
var scheme = cast[PKScheme](cast[int8](id))
when key is PrivateKey:
var nkey = PrivateKey(scheme: scheme)
else:
var nkey = PublicKey(scheme: scheme)
case scheme:
of PKScheme.RSA:
when supported(PKScheme.RSA):
if init(nkey.rsakey, buffer).isOk:
key = nkey
true
else:
false
else:
false
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
if init(nkey.edkey, buffer):
key = nkey
true
else:
false
else:
false
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
if init(nkey.eckey, buffer).isOk:
key = nkey
true
else:
false
else:
false
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
if init(nkey.skkey, buffer).isOk:
key = nkey
true
else:
false
else:
false
{.push warning[ProveField]:off.} # https://github.com/nim-lang/Nim/issues/22060
proc init*(key: var PrivateKey, data: openArray[byte]): bool =
initImpl(key, data)
proc init*(key: var PublicKey, data: openArray[byte]): bool =
initImpl(key, data)
{.pop.}
proc init*(sig: var Signature, data: openArray[byte]): bool =
## Initialize signature ``sig`` from raw binary form.
##
## Returns ``true`` on success.
if len(data) > 0:
sig.data = @data
result = true
proc init*[T: PrivateKey|PublicKey](key: var T, data: string): bool =
## Initialize private/public key ``key`` from libp2p's protobuf serialized
## hexadecimal string representation.
##
## Returns ``true`` on success.
key.init(ncrutils.fromHex(data))
proc init*(sig: var Signature, data: string): bool =
## Initialize signature ``sig`` from serialized hexadecimal string
## representation.
##
## Returns ``true`` on success.
sig.init(ncrutils.fromHex(data))
proc init*(t: typedesc[PrivateKey],
data: openArray[byte]): CryptoResult[PrivateKey] =
## Create new private key from libp2p's protobuf serialized binary form.
var res: t
if not res.init(data):
err(KeyError)
else:
ok(res)
proc init*(t: typedesc[PublicKey],
data: openArray[byte]): CryptoResult[PublicKey] =
## Create new public key from libp2p's protobuf serialized binary form.
var res: t
if not res.init(data):
err(KeyError)
else:
ok(res)
proc init*(t: typedesc[Signature],
data: openArray[byte]): CryptoResult[Signature] =
## Create new public key from libp2p's protobuf serialized binary form.
var res: t
if not res.init(data):
err(SigError)
else:
ok(res)
proc init*(t: typedesc[PrivateKey], data: string): CryptoResult[PrivateKey] =
## Create new private key from libp2p's protobuf serialized hexadecimal string
## form.
t.init(ncrutils.fromHex(data))
when supported(PKScheme.RSA):
proc init*(t: typedesc[PrivateKey], key: rsa.RsaPrivateKey): PrivateKey =
PrivateKey(scheme: RSA, rsakey: key)
proc init*(t: typedesc[PublicKey], key: rsa.RsaPublicKey): PublicKey =
PublicKey(scheme: RSA, rsakey: key)
when supported(PKScheme.Ed25519):
proc init*(t: typedesc[PrivateKey], key: EdPrivateKey): PrivateKey =
PrivateKey(scheme: Ed25519, edkey: key)
proc init*(t: typedesc[PublicKey], key: EdPublicKey): PublicKey =
PublicKey(scheme: Ed25519, edkey: key)
when supported(PKScheme.Secp256k1):
proc init*(t: typedesc[PrivateKey], key: SkPrivateKey): PrivateKey =
PrivateKey(scheme: Secp256k1, skkey: key)
proc init*(t: typedesc[PublicKey], key: SkPublicKey): PublicKey =
PublicKey(scheme: Secp256k1, skkey: key)
when supported(PKScheme.ECDSA):
proc init*(t: typedesc[PrivateKey], key: ecnist.EcPrivateKey): PrivateKey =
PrivateKey(scheme: ECDSA, eckey: key)
proc init*(t: typedesc[PublicKey], key: ecnist.EcPublicKey): PublicKey =
PublicKey(scheme: ECDSA, eckey: key)
proc init*(t: typedesc[PublicKey], data: string): CryptoResult[PublicKey] =
## Create new public key from libp2p's protobuf serialized hexadecimal string
## form.
t.init(ncrutils.fromHex(data))
proc init*(t: typedesc[Signature], data: string): CryptoResult[Signature] =
## Create new signature from serialized hexadecimal string form.
t.init(ncrutils.fromHex(data))
proc `==`*(key1, key2: PublicKey): bool {.inline.} =
## Return ``true`` if two public keys ``key1`` and ``key2`` of the same
## scheme and equal.
if key1.scheme == key2.scheme:
case key1.scheme
of PKScheme.RSA:
when supported(PKScheme.RSA):
(key1.rsakey == key2.rsakey)
else:
false
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
(key1.edkey == key2.edkey)
else:
false
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
(key1.eckey == key2.eckey)
else:
false
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
(key1.skkey == key2.skkey)
else:
false
else:
false
proc `==`*(key1, key2: PrivateKey): bool =
## Return ``true`` if two private keys ``key1`` and ``key2`` of the same
## scheme and equal.
if key1.scheme == key2.scheme:
case key1.scheme
of PKScheme.RSA:
when supported(PKScheme.RSA):
(key1.rsakey == key2.rsakey)
else:
false
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
(key1.edkey == key2.edkey)
else:
false
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
(key1.eckey == key2.eckey)
else:
false
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
(key1.skkey == key2.skkey)
else:
false
else:
false
proc `$`*(key: PrivateKey|PublicKey): string =
## Get string representation of private/public key ``key``.
case key.scheme:
of PKScheme.RSA:
when supported(PKScheme.RSA):
$(key.rsakey)
else:
"unsupported RSA key"
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
"ed25519 key (" & $key.edkey & ")"
else:
"unsupported ed25519 key"
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
"secp256r1 key (" & $key.eckey & ")"
else:
"unsupported secp256r1 key"
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
"secp256k1 key (" & $key.skkey & ")"
else:
"unsupported secp256k1 key"
func shortLog*(key: PrivateKey|PublicKey): string =
## Get short string representation of private/public key ``key``.
case key.scheme:
of PKScheme.RSA:
when supported(PKScheme.RSA):
($key.rsakey).shortLog
else:
"unsupported RSA key"
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
"ed25519 key (" & ($key.edkey).shortLog & ")"
else:
"unsupported ed25519 key"
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
"secp256r1 key (" & ($key.eckey).shortLog & ")"
else:
"unsupported secp256r1 key"
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
"secp256k1 key (" & ($key.skkey).shortLog & ")"
else:
"unsupported secp256k1 key"
proc `$`*(sig: Signature): string =
## Get string representation of signature ``sig``.
result = ncrutils.toHex(sig.data)
proc sign*(key: PrivateKey,
data: openArray[byte]): CryptoResult[Signature] {.gcsafe.} =
## Sign message ``data`` using private key ``key`` and return generated
## signature in raw binary form.
var res: Signature
case key.scheme:
of PKScheme.RSA:
when supported(PKScheme.RSA):
let sig = ? key.rsakey.sign(data).orError(SigError)
res.data = ? sig.getBytes().orError(SigError)
ok(res)
else:
err(SchemeError)
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
let sig = key.edkey.sign(data)
res.data = sig.getBytes()
ok(res)
else:
err(SchemeError)
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
let sig = ? key.eckey.sign(data).orError(SigError)
res.data = ? sig.getBytes().orError(SigError)
ok(res)
else:
err(SchemeError)
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
let sig = key.skkey.sign(data)
res.data = sig.getBytes()
ok(res)
else:
err(SchemeError)
proc verify*(sig: Signature, message: openArray[byte], key: PublicKey): bool =
## Verify signature ``sig`` using message ``message`` and public key ``key``.
## Return ``true`` if message signature is valid.
case key.scheme:
of PKScheme.RSA:
when supported(PKScheme.RSA):
var signature: RsaSignature
if signature.init(sig.data).isOk:
signature.verify(message, key.rsakey)
else:
false
else:
false
of PKScheme.Ed25519:
when supported(PKScheme.Ed25519):
var signature: EdSignature
if signature.init(sig.data):
signature.verify(message, key.edkey)
else:
false
else:
false
of PKScheme.ECDSA:
when supported(PKScheme.ECDSA):
var signature: EcSignature
if signature.init(sig.data).isOk:
signature.verify(message, key.eckey)
else:
false
else:
false
of PKScheme.Secp256k1:
when supported(PKScheme.Secp256k1):
var signature: SkSignature
if signature.init(sig.data).isOk:
signature.verify(message, key.skkey)
else:
false
else:
false
template makeSecret(buffer, hmactype, secret, seed: untyped) {.dirty.}=
var ctx: hmactype
var j = 0
# We need to strip leading zeros, because Go bigint serialization do it.
var offset = 0
for i in 0..<len(secret):
if secret[i] != 0x00'u8:
break
inc(offset)
ctx.init(secret.toOpenArray(offset, secret.high))
ctx.update(seed)
var a = ctx.finish()
while j < len(buffer):
ctx.init(secret.toOpenArray(offset, secret.high))
ctx.update(a.data)
ctx.update(seed)
var b = ctx.finish()
var todo = len(b.data)
if j + todo > len(buffer):
todo = len(buffer) - j
copyMem(addr buffer[j], addr b.data[0], todo)
j += todo
ctx.init(secret.toOpenArray(offset, secret.high))
ctx.update(a.data)
a = ctx.finish()
proc stretchKeys*(cipherType: string, hashType: string,
sharedSecret: seq[byte]): Secret =
## Expand shared secret to cryptographic keys.
if cipherType == "AES-128":
result.ivsize = aes128.sizeBlock
result.keysize = aes128.sizeKey
elif cipherType == "AES-256":
result.ivsize = aes256.sizeBlock
result.keysize = aes256.sizeKey
elif cipherType == "TwofishCTR":
result.ivsize = twofish256.sizeBlock
result.keysize = twofish256.sizeKey
var seed = "key expansion"
result.macsize = 20
let length = result.ivsize + result.keysize + result.macsize
result.data = newSeq[byte](2 * length)
if hashType == "SHA256":
makeSecret(result.data, HMAC[sha256], sharedSecret, seed)
elif hashType == "SHA512":
makeSecret(result.data, HMAC[sha512], sharedSecret, seed)
template goffset*(secret, id, o: untyped): untyped =
id * (len(secret.data) shr 1) + o
template ivOpenArray*(secret: Secret, id: int): untyped =
toOpenArray(secret.data, goffset(secret, id, 0),
goffset(secret, id, secret.ivsize - 1))
template keyOpenArray*(secret: Secret, id: int): untyped =
toOpenArray(secret.data, goffset(secret, id, secret.ivsize),
goffset(secret, id, secret.ivsize + secret.keysize - 1))
template macOpenArray*(secret: Secret, id: int): untyped =
toOpenArray(secret.data, goffset(secret, id, secret.ivsize + secret.keysize),
goffset(secret, id, secret.ivsize + secret.keysize + secret.macsize - 1))
proc iv*(secret: Secret, id: int): seq[byte] {.inline.} =
## Get array of bytes with with initial vector.
result = newSeq[byte](secret.ivsize)
var offset = if id == 0: 0 else: (len(secret.data) div 2)
copyMem(addr result[0], unsafeAddr secret.data[offset], secret.ivsize)
proc key*(secret: Secret, id: int): seq[byte] {.inline.} =
result = newSeq[byte](secret.keysize)
var offset = if id == 0: 0 else: (len(secret.data) div 2)
offset += secret.ivsize
copyMem(addr result[0], unsafeAddr secret.data[offset], secret.keysize)
proc mac*(secret: Secret, id: int): seq[byte] {.inline.} =
result = newSeq[byte](secret.macsize)
var offset = if id == 0: 0 else: (len(secret.data) div 2)
offset += secret.ivsize + secret.keysize
copyMem(addr result[0], unsafeAddr secret.data[offset], secret.macsize)
proc ephemeral*(
scheme: ECDHEScheme,
rng: var HmacDrbgContext): CryptoResult[EcKeyPair] =
## Generate ephemeral keys used to perform ECDHE.
var keypair: EcKeyPair
if scheme == Secp256r1:
keypair = ? EcKeyPair.random(Secp256r1, rng).orError(KeyError)
elif scheme == Secp384r1:
keypair = ? EcKeyPair.random(Secp384r1, rng).orError(KeyError)
elif scheme == Secp521r1:
keypair = ? EcKeyPair.random(Secp521r1, rng).orError(KeyError)
ok(keypair)
proc ephemeral*(
scheme: string, rng: var HmacDrbgContext): CryptoResult[EcKeyPair] =
## Generate ephemeral keys used to perform ECDHE using string encoding.
##
## Currently supported encoding strings are P-256, P-384, P-521, if encoding
## string is not supported P-521 key will be generated.
if scheme == "P-256":
ephemeral(Secp256r1, rng)
elif scheme == "P-384":
ephemeral(Secp384r1, rng)
elif scheme == "P-521":
ephemeral(Secp521r1, rng)
else:
ephemeral(Secp521r1, rng)
proc getOrder*(remotePubkey, localNonce: openArray[byte],
localPubkey, remoteNonce: openArray[byte]): CryptoResult[int] =
## Compare values and calculate `order` parameter.
var ctx: sha256
ctx.init()
ctx.update(remotePubkey)
ctx.update(localNonce)
var digest1 = ctx.finish()
ctx.init()
ctx.update(localPubkey)
ctx.update(remoteNonce)
var digest2 = ctx.finish()
var mh1 = ? MultiHash.init(multiCodec("sha2-256"), digest1).orError(HashError)
var mh2 = ? MultiHash.init(multiCodec("sha2-256"), digest2).orError(HashError)
var res = 0;
for i in 0 ..< len(mh1.data.buffer):
res = int(mh1.data.buffer[i]) - int(mh2.data.buffer[i])
if res != 0:
if res < 0:
res = -1
elif res > 0:
res = 1
break
ok(res)
proc selectBest*(order: int, p1, p2: string): string =
## Determines which algorithm to use from list `p1` and `p2`.
##
## Returns empty string if there no algorithms in common.
var f, s: seq[string]
if order < 0:
f = strutils.split(p2, ",")
s = strutils.split(p1, ",")
elif order > 0:
f = strutils.split(p1, ",")
s = strutils.split(p2, ",")
else:
var p = strutils.split(p1, ",")
return p[0]
for felement in f:
for selement in s:
if felement == selement:
return felement
proc createProposal*(nonce, pubkey: openArray[byte],
exchanges, ciphers, hashes: string): seq[byte] =
## Create SecIO proposal message using random ``nonce``, local public key
## ``pubkey``, comma-delimieted list of supported exchange schemes
## ``exchanges``, comma-delimeted list of supported ciphers ``ciphers`` and
## comma-delimeted list of supported hashes ``hashes``.
var msg = initProtoBuffer({WithUint32BeLength})
msg.write(1, nonce)
msg.write(2, pubkey)
msg.write(3, exchanges)
msg.write(4, ciphers)
msg.write(5, hashes)
msg.finish()
msg.buffer
proc decodeProposal*(message: seq[byte], nonce, pubkey: var seq[byte],
exchanges, ciphers, hashes: var string): bool =
## Parse incoming proposal message and decode remote random nonce ``nonce``,
## remote public key ``pubkey``, comma-delimieted list of supported exchange
## schemes ``exchanges``, comma-delimeted list of supported ciphers
## ``ciphers`` and comma-delimeted list of supported hashes ``hashes``.
##
## Procedure returns ``true`` on success and ``false`` on error.
var pb = initProtoBuffer(message)
let r1 = pb.getField(1, nonce)
let r2 = pb.getField(2, pubkey)
let r3 = pb.getField(3, exchanges)
let r4 = pb.getField(4, ciphers)
let r5 = pb.getField(5, hashes)
r1.get(false) and r2.get(false) and r3.get(false) and
r4.get(false) and r5.get(false)
proc createExchange*(epubkey, signature: openArray[byte]): seq[byte] =
## Create SecIO exchange message using ephemeral public key ``epubkey`` and
## signature of proposal blocks ``signature``.
var msg = initProtoBuffer({WithUint32BeLength})
msg.write(1, epubkey)
msg.write(2, signature)
msg.finish()
msg.buffer
proc decodeExchange*(message: seq[byte],
pubkey, signature: var seq[byte]): bool =
## Parse incoming exchange message and decode remote ephemeral public key
## ``pubkey`` and signature ``signature``.
##
## Procedure returns ``true`` on success and ``false`` on error.
var pb = initProtoBuffer(message)
let r1 = pb.getField(1, pubkey)
let r2 = pb.getField(2, signature)
r1.get(false) and r2.get(false)
## Serialization/Deserialization helpers
proc write*(vb: var VBuffer, pubkey: PublicKey) {.
inline, raises: [ResultError[CryptoError]].} =
## Write PublicKey value ``pubkey`` to buffer ``vb``.
vb.writeSeq(pubkey.getBytes().tryGet())
proc write*(vb: var VBuffer, seckey: PrivateKey) {.
inline, raises: [ResultError[CryptoError]].} =
## Write PrivateKey value ``seckey`` to buffer ``vb``.
vb.writeSeq(seckey.getBytes().tryGet())
proc write*(vb: var VBuffer, sig: PrivateKey) {.
inline, raises: [ResultError[CryptoError]].} =
## Write Signature value ``sig`` to buffer ``vb``.
vb.writeSeq(sig.getBytes().tryGet())
proc write*[T: PublicKey|PrivateKey](pb: var ProtoBuffer, field: int,
key: T) {.
inline, raises: [ResultError[CryptoError]].} =
write(pb, field, key.getBytes().tryGet())
proc write*(pb: var ProtoBuffer, field: int, sig: Signature) {.
inline, raises: [].} =
write(pb, field, sig.getBytes())
proc getField*[T: PublicKey|PrivateKey](pb: ProtoBuffer, field: int,
value: var T): ProtoResult[bool] =
## Deserialize public/private key from protobuf's message ``pb`` using field
## index ``field``.
##
## On success deserialized key will be stored in ``value``.
var buffer: seq[byte]
var key: T
let res = ? pb.getField(field, buffer)
if not(res):
ok(false)
else:
if key.init(buffer):
value = key
ok(true)
else:
err(ProtoError.IncorrectBlob)
proc getField*(pb: ProtoBuffer, field: int,
value: var Signature): ProtoResult[bool] =
## Deserialize signature from protobuf's message ``pb`` using field index
## ``field``.
##
## On success deserialized signature will be stored in ``value``.
var buffer: seq[byte]
var sig: Signature
let res = ? pb.getField(field, buffer)
if not(res):
ok(false)
else:
if sig.init(buffer):
value = sig
ok(true)
else:
err(ProtoError.IncorrectBlob)