nim-libp2p/libp2p/crypto/crypto.nim

488 lines
16 KiB
Nim

## Nim-Libp2p
## Copyright (c) 2018 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.
import rsa, ecnist
import ed25519/ed25519
import ../protobuf/minprotobuf
import nimcrypto/[rijndael, blowfish, sha, sha2, hash, hmac, utils]
type
PKScheme* = enum
RSA = 0,
Ed25519,
Secp256k1,
ECDSA,
NoSupport
CipherScheme* = enum
Aes128 = 0,
Aes256,
Blowfish
DigestSheme* = enum
Sha1,
Sha256,
Sha512
ECDHEScheme* = EcCurveKind
PublicKey* = object
case scheme*: PKScheme
of RSA:
rsakey*: RsaPublicKey
of Ed25519:
edkey*: EdPublicKey
of Secp256k1:
discard
of ECDSA:
eckey*: EcPublicKey
of NoSupport:
discard
PrivateKey* = object
case scheme*: PKScheme
of RSA:
rsakey*: RsaPrivateKey
of Ed25519:
edkey*: EdPrivateKey
of Secp256k1:
discard
of ECDSA:
eckey*: EcPrivateKey
of NoSupport:
discard
KeyPair* = object
seckey*: PrivateKey
pubkey*: PublicKey
Secret* = object
ivsize*: int
keysize*: int
macsize*: int
data*: seq[byte]
P2pKeyError* = object of Exception
const
SupportedSchemes* = {RSA, Ed25519, ECDSA}
SupportedSchemesInt* = {int8(RSA), int8(Ed25519), int8(ECDSA)}
proc random*(t: typedesc[PrivateKey], scheme: PKScheme,
bits = DefaultKeySize): PrivateKey =
## Generate random private key for scheme ``scheme``.
##
## ``bits`` is number of bits for RSA key, ``bits`` value must be in
## [512, 4096], default value is 2048 bits.
assert(scheme in SupportedSchemes)
result = PrivateKey(scheme: scheme)
if scheme == RSA:
result.rsakey = RsaPrivateKey.random(bits)
elif scheme == Ed25519:
result.edkey = EdPrivateKey.random()
elif scheme == ECDSA:
result.eckey = EcPrivateKey.random(Secp256r1)
proc random*(t: typedesc[KeyPair], scheme: PKScheme,
bits = DefaultKeySize): 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.
assert(scheme in SupportedSchemes)
result.seckey = PrivateKey(scheme: scheme)
result.pubkey = PublicKey(scheme: scheme)
if scheme == RSA:
var pair = RsaKeyPair.random(bits)
result.seckey.rsakey = pair.seckey
result.pubkey.rsakey = pair.pubkey
elif scheme == Ed25519:
var pair = EdKeyPair.random()
result.seckey.edkey = pair.seckey
result.pubkey.edkey = pair.pubkey
elif scheme == ECDSA:
var pair = EcKeyPair.random(Secp256r1)
result.seckey.eckey = pair.seckey
result.pubkey.eckey = pair.pubkey
proc getKey*(key: PrivateKey): PublicKey =
## Get public key from corresponding private key ``key``.
result = PublicKey(scheme: key.scheme)
if key.scheme == RSA:
result.rsakey = key.rsakey.getKey()
elif key.scheme == Ed25519:
result.edkey = key.edkey.getKey()
elif key.scheme == ECDSA:
result.eckey = key.eckey.getKey()
proc toRawBytes*(key: PrivateKey, data: var openarray[byte]): 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``.
if key.scheme == RSA:
result = key.rsakey.toBytes(data)
elif key.scheme == Ed25519:
result = key.edkey.toBytes(data)
elif key.scheme == ECDSA:
result = key.eckey.toBytes(data)
proc toRawBytes*(key: PublicKey, data: var openarray[byte]): int =
## Serialize public key ``key`` (using scheme's own serialization) and store
## it to ``data``.
##
## Returns number of bytes (octets) needed to store public key ``key``.
if key.scheme == RSA:
result = key.rsakey.toBytes(data)
elif key.scheme == Ed25519:
result = key.edkey.toBytes(data)
elif key.scheme == ECDSA:
result = key.eckey.toBytes(data)
proc getRawBytes*(key: PrivateKey): seq[byte] =
## Return private key ``key`` in binary form (using scheme's own
## serialization).
if key.scheme == RSA:
result = key.rsakey.getBytes()
elif key.scheme == Ed25519:
result = key.edkey.getBytes()
elif key.scheme == ECDSA:
result = key.eckey.getBytes()
proc getRawBytes*(key: PublicKey): seq[byte] =
## Return public key ``key`` in binary form (using scheme's own
## serialization).
if key.scheme == RSA:
result = key.rsakey.getBytes()
elif key.scheme == Ed25519:
result = key.edkey.getBytes()
elif key.scheme == ECDSA:
result = key.eckey.getBytes()
proc toBytes*(key: PrivateKey, data: var openarray[byte]): 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(initProtoField(1, cast[uint64](key.scheme)))
msg.write(initProtoField(2, key.getRawBytes()))
msg.finish()
result = len(msg.buffer)
if len(data) >= result:
copyMem(addr data[0], addr msg.buffer[0], len(msg.buffer))
proc toBytes*(key: PublicKey, data: var openarray[byte]): 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(initProtoField(1, cast[uint64](key.scheme)))
msg.write(initProtoField(2, key.getRawBytes()))
msg.finish()
result = len(msg.buffer)
if len(data) >= result:
copyMem(addr data[0], addr msg.buffer[0], len(msg.buffer))
proc getBytes*(key: PrivateKey): seq[byte] =
## Return private key ``key`` in binary form (using libp2p's protobuf
## serialization).
var msg = initProtoBuffer()
msg.write(initProtoField(1, cast[uint64](key.scheme)))
msg.write(initProtoField(2, key.getRawBytes()))
msg.finish()
result = msg.buffer
proc getBytes*(key: PublicKey): seq[byte] =
## Return public key ``key`` in binary form (using libp2p's protobuf
## serialization).
var msg = initProtoBuffer()
msg.write(initProtoField(1, cast[uint64](key.scheme)))
msg.write(initProtoField(2, key.getRawBytes()))
msg.finish()
result = msg.buffer
proc init*(key: var PrivateKey, 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:
var pb = initProtoBuffer(@data)
if pb.getVarintValue(1, id) != 0:
if pb.getBytes(2, buffer) != 0:
if cast[int8](id) in SupportedSchemesInt:
var scheme = cast[PKScheme](cast[int8](id))
var nkey = PrivateKey(scheme: scheme)
if scheme == RSA:
if init(nkey.rsakey, buffer) == Asn1Status.Success:
key = nkey
result = true
elif scheme == Ed25519:
if init(nkey.edkey, buffer):
key = nkey
result = true
elif scheme == ECDSA:
if init(nkey.eckey, buffer) == Asn1Status.Success:
key = nkey
result = true
proc init*(key: var PublicKey, data: openarray[byte]): bool =
## Initialize public 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:
var pb = initProtoBuffer(@data)
if pb.getVarintValue(1, id) != 0:
if pb.getBytes(2, buffer) != 0:
if cast[int8](id) in SupportedSchemesInt:
var scheme = cast[PKScheme](cast[int8](id))
var nkey = PublicKey(scheme: scheme)
if scheme == RSA:
if init(nkey.rsakey, buffer) == Asn1Status.Success:
key = nkey
result = true
elif scheme == Ed25519:
if init(nkey.edkey, buffer):
key = nkey
result = true
elif scheme == ECDSA:
if init(nkey.eckey, buffer) == Asn1Status.Success:
key = nkey
result = true
proc init*(key: var PrivateKey, data: string): bool =
## Initialize private key ``key`` from libp2p's protobuf serialized
## hexadecimal string representation.
##
## Returns ``true`` on success.
result = key.init(fromHex(data))
proc init*(key: var PublicKey, data: string): bool =
## Initialize public key ``key`` from libp2p's protobuf serialized
## hexadecimal string representation.
##
## Returns ``true`` on success.
result = key.init(fromHex(data))
proc init*(t: typedesc[PrivateKey], data: openarray[byte]): PrivateKey =
## Create new private key from libp2p's protobuf serialized binary form.
if not result.init(data):
raise newException(P2pKeyError, "Incorrect binary form")
proc init*(t: typedesc[PublicKey], data: openarray[byte]): PublicKey =
## Create new public key from libp2p's protobuf serialized binary form.
if not result.init(data):
raise newException(P2pKeyError, "Incorrect binary form")
proc init*(t: typedesc[PrivateKey], data: string): PrivateKey =
## Create new private key from libp2p's protobuf serialized hexadecimal string
## form.
result = t.init(fromHex(data))
proc init*(t: typedesc[PublicKey], data: string): PublicKey =
## Create new public key from libp2p's protobuf serialized hexadecimal string
## form.
result = t.init(fromHex(data))
proc `==`*(key1, key2: PublicKey): bool =
## Return ``true`` if two public keys ``key1`` and ``key2`` of the same
## scheme and equal.
if key1.scheme == key2.scheme:
if key1.scheme == RSA:
result = (key1.rsakey == key2.rsakey)
elif key1.scheme == Ed25519:
result = (key1.edkey == key2.edkey)
elif key1.scheme == ECDSA:
result = (key1.eckey == key2.eckey)
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:
if key1.scheme == RSA:
result = (key1.rsakey == key2.rsakey)
elif key1.scheme == Ed25519:
result = (key1.edkey == key2.edkey)
elif key1.scheme == ECDSA:
result = (key1.eckey == key2.eckey)
proc `$`*(key: PrivateKey): string =
## Get string representation of private key ``key``.
if key.scheme == RSA:
result = $(key.rsakey)
elif key.scheme == Ed25519:
result = "Ed25519 key ("
result.add($(key.edkey))
result.add(")")
elif key.scheme == ECDSA:
result = "Secp256r1 key ("
result.add($(key.eckey))
result.add(")")
proc `$`*(key: PublicKey): string =
## Get string representation of public key ``key``.
if key.scheme == RSA:
result = $(key.rsakey)
elif key.scheme == Ed25519:
result = "Ed25519 key ("
result.add($(key.edkey))
result.add(")")
elif key.scheme == ECDSA:
result = "Secp256r1 key ("
result.add($(key.eckey))
result.add(")")
proc sign*(key: PrivateKey, data: openarray[byte]): seq[byte] =
## Sign message ``data`` using private key ``key`` and return generated
## signature in raw binary form.
if key.scheme == RSA:
var sig = key.rsakey.sign(data)
result = sig.getBytes()
elif key.scheme == Ed25519:
var sig = key.edkey.sign(data)
result = sig.getBytes()
elif key.scheme == ECDSA:
var sig = key.eckey.sign(data)
result = sig.getBytes()
proc verify*(sig: openarray[byte], message: openarray[byte],
key: PublicKey): bool =
## Verify signature ``sig`` using message ``message`` and public key ``key``.
## Return ``true`` if message signature is valid.
if key.scheme == RSA:
var signature: RsaSignature
if signature.init(sig) == Asn1Status.Success:
result = signature.verify(message, key.rsakey)
elif key.scheme == Ed25519:
var signature: EdSignature
if signature.init(sig):
result = signature.verify(message, key.edkey)
elif key.scheme == ECDSA:
var signature: EcSignature
if signature.init(sig) == Asn1Status.Success:
result = signature.verify(message, key.eckey)
template makeSecret(buffer, hmactype, secret, seed) =
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, len(secret) - 1))
ctx.update(seed)
var a = ctx.finish()
while j < len(buffer):
ctx.init(secret.toOpenArray(offset, len(secret) - 1))
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, len(secret) - 1))
ctx.update(a.data)
a = ctx.finish()
proc stretchKeys*(cipherScheme: CipherScheme, hashScheme: DigestSheme,
secret: openarray[byte]): Secret =
## Expand shared secret to cryptographic keys.
if cipherScheme == Aes128:
result.ivsize = aes128.sizeBlock
result.keysize = aes128.sizeKey
elif cipherScheme == Aes256:
result.ivsize = aes256.sizeBlock
result.keysize = aes256.sizeKey
elif cipherScheme == Blowfish:
result.ivsize = 8
result.keysize = 32
var seed = "key expansion"
result.macsize = 20
let length = result.ivsize + result.keysize + result.macsize
result.data = newSeq[byte](2 * length)
if hashScheme == Sha256:
makeSecret(result.data, HMAC[sha256], secret, seed)
elif hashScheme == Sha512:
makeSecret(result.data, HMAC[sha512], secret, seed)
elif hashScheme == Sha1:
makeSecret(result.data, HMAC[sha1], secret, 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): KeyPair =
## Generate ephemeral keys used to perform ECDHE.
var keypair: EcKeyPair
if scheme == Secp256r1:
keypair = EcKeyPair.random(Secp256r1)
elif scheme == Secp384r1:
keypair = EcKeyPair.random(Secp384r1)
elif scheme == Secp521r1:
keypair = EcKeyPair.random(Secp521r1)
result.seckey = PrivateKey(scheme: ECDSA)
result.pubkey = PublicKey(scheme: ECDSA)
result.seckey.eckey = keypair.seckey
result.pubkey.eckey = keypair.pubkey
proc makeSecret*(remoteEPublic: PublicKey, localEPrivate: PrivateKey,
data: var openarray[byte]): int =
## Calculate shared secret using remote ephemeral public key
## ``remoteEPublic`` and local ephemeral private key ``localEPrivate`` and
## store shared secret to ``data``
##
## Returns number of bytes (octets) used to store shared secret data, or
## ``0`` on error.
if remoteEPublic.scheme == ECDSA:
if localEPrivate.scheme == remoteEPublic.scheme:
result = toSecret(remoteEPublic.eckey, localEPrivate.eckey, data)