382 lines
13 KiB
Nim
382 lines
13 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.
|
|
import strutils
|
|
import secp256k1, nimcrypto/sysrand, nimcrypto/utils, nimcrypto/hash,
|
|
nimcrypto/sha2
|
|
export sha2
|
|
|
|
const
|
|
SkRawPrivateKeySize* = 256 div 8
|
|
## Size of private key in octets (bytes)
|
|
SkRawSignatureSize* = SkRawPrivateKeySize * 2 + 1
|
|
## Size of signature in octets (bytes)
|
|
SkRawPublicKeySize* = SkRawPrivateKeySize + 1
|
|
## Size of public key in octets (bytes)
|
|
|
|
type
|
|
SkPublicKey* = secp256k1_pubkey
|
|
## Representation of public key.
|
|
|
|
SkPrivateKey* = object
|
|
## Representation of secret key.
|
|
data*: array[SkRawPrivateKeySize, byte]
|
|
|
|
SkKeyPair* = object
|
|
## Representation of private/public keys pair.
|
|
seckey*: SkPrivateKey
|
|
pubkey*: SkPublicKey
|
|
|
|
SkSignature* = secp256k1_ecdsa_recoverable_signature
|
|
## Representation of signature.
|
|
|
|
SkContext* = ref object
|
|
## Representation of Secp256k1 context object.
|
|
context: ptr secp256k1_context
|
|
error: string
|
|
|
|
Secp256k1Error* = object of CatchableError
|
|
## Exceptions generated by `libsecp256k1`
|
|
|
|
##
|
|
## Private procedures interface
|
|
##
|
|
|
|
var secpContext {.threadvar.}: SkContext
|
|
## Thread local variable which holds current context
|
|
|
|
proc illegalCallback(message: cstring, data: pointer) {.cdecl.} =
|
|
let ctx = cast[SkContext](data)
|
|
ctx.error = $message
|
|
|
|
proc errorCallback(message: cstring, data: pointer) {.cdecl.} =
|
|
let ctx = cast[SkContext](data)
|
|
ctx.error = $message
|
|
|
|
proc shutdownLibsecp256k1(ctx: SkContext) =
|
|
# TODO: use destructor when finalizer are deprecated for destructors
|
|
if not(isNil(ctx.context)):
|
|
secp256k1_context_destroy(ctx.context)
|
|
|
|
proc newSkContext(): SkContext =
|
|
## Create new Secp256k1 context object.
|
|
new(result, shutdownLibsecp256k1)
|
|
let flags = cuint(SECP256K1_CONTEXT_VERIFY or SECP256K1_CONTEXT_SIGN)
|
|
result.context = secp256k1_context_create(flags)
|
|
secp256k1_context_set_illegal_callback(result.context, illegalCallback,
|
|
cast[pointer](result))
|
|
secp256k1_context_set_error_callback(result.context, errorCallback,
|
|
cast[pointer](result))
|
|
result.error = ""
|
|
|
|
proc getContext(): SkContext =
|
|
## Get current `EccContext`
|
|
if isNil(secpContext):
|
|
secpContext = newSkContext()
|
|
result = secpContext
|
|
|
|
template raiseSecp256k1Error() =
|
|
## Raises `libsecp256k1` error as exception
|
|
let mctx = getContext()
|
|
if len(mctx.error) > 0:
|
|
let msg = mctx.error
|
|
mctx.error.setLen(0)
|
|
raise newException(Secp256k1Error, msg)
|
|
else:
|
|
raise newException(Secp256k1Error, "")
|
|
|
|
proc init*(key: var SkPrivateKey, data: openarray[byte]): bool =
|
|
## Initialize Secp256k1 `private key` ``key`` from raw binary
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns ``true`` on success.
|
|
let ctx = getContext()
|
|
if len(data) >= SkRawPrivateKeySize:
|
|
let res = secp256k1_ec_seckey_verify(ctx.context,
|
|
cast[ptr cuchar](unsafeAddr data[0]))
|
|
result = (res == 1) and (len(ctx.error) == 0)
|
|
if result:
|
|
copyMem(addr key.data[0], unsafeAddr data[0], SkRawPrivateKeySize)
|
|
|
|
proc init*(key: var SkPrivateKey, data: string): bool {.inline.} =
|
|
## Initialize Secp256k1 `private key` ``key`` from hexadecimal string
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns ``true`` on success.
|
|
var buffer: seq[byte]
|
|
try:
|
|
buffer = fromHex(stripSpaces(data))
|
|
except:
|
|
return false
|
|
result = init(key, buffer)
|
|
|
|
proc init*(key: var SkPublicKey, data: openarray[byte]): bool =
|
|
## Initialize Secp256k1 `public key` ``key`` from raw binary
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns ``true`` on success.
|
|
let ctx = getContext()
|
|
var length = 0
|
|
if len(data) > 0:
|
|
if data[0] == 0x02'u8 or data[0] == 0x03'u8:
|
|
length = min(len(data), 33)
|
|
elif data[0] == 0x04'u8 or data[0] == 0x06'u8 or data[0] == 0x07'u8:
|
|
length = min(len(data), 65)
|
|
else:
|
|
return false
|
|
let res = secp256k1_ec_pubkey_parse(ctx.context, addr key,
|
|
cast[ptr cuchar](unsafeAddr data[0]),
|
|
length)
|
|
result = (res == 1) and (len(ctx.error) == 0)
|
|
|
|
proc init*(key: var SkPublicKey, data: string): bool =
|
|
## Initialize Secp256k1 `public key` ``key`` from hexadecimal string
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns ``true`` on success.
|
|
var buffer: seq[byte]
|
|
try:
|
|
buffer = fromHex(stripSpaces(data))
|
|
except:
|
|
return false
|
|
result = init(key, buffer)
|
|
|
|
proc init*(sig: var SkSignature, data: openarray[byte]): bool =
|
|
## Initialize Secp256k1 `signature` ``sig`` from raw binary
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns ``true`` on success.
|
|
let ctx = getContext()
|
|
let length = len(data)
|
|
if length >= SkRawSignatureSize:
|
|
var recid = cint(data[SkRawPrivateKeySize * 2])
|
|
let res = secp256k1_ecdsa_recoverable_signature_parse_compact(ctx.context,
|
|
addr sig, cast[ptr cuchar](unsafeAddr data[0]), recid)
|
|
result = (res == 1) and (len(ctx.error) == 0)
|
|
|
|
proc init*(sig: var SkSignature, data: string): bool =
|
|
## Initialize Secp256k1 `signature` ``sig`` from hexadecimal string
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns ``true`` on success.
|
|
var buffer: seq[byte]
|
|
try:
|
|
buffer = fromHex(stripSpaces(data))
|
|
except:
|
|
return false
|
|
result = init(sig, buffer)
|
|
|
|
proc init*(t: typedesc[SkPrivateKey],
|
|
data: openarray[byte]): SkPrivateKey {.inline.} =
|
|
## Initialize Secp256k1 `private key` from raw binary
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns `private key` on success.
|
|
if not init(result, data):
|
|
raise newException(Secp256k1Error, "Incorrect binary form")
|
|
|
|
proc init*(t: typedesc[SkPrivateKey],
|
|
data: string): SkPrivateKey {.inline.} =
|
|
## Initialize Secp256k1 `private key` from hexadecimal string
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns `private key` on success.
|
|
if not init(result, data):
|
|
raise newException(Secp256k1Error, "Incorrect binary form")
|
|
|
|
proc init*(t: typedesc[SkPublicKey],
|
|
data: openarray[byte]): SkPublicKey {.inline.} =
|
|
## Initialize Secp256k1 `public key` from raw binary
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns `public key` on success.
|
|
if not init(result, data):
|
|
raise newException(Secp256k1Error, "Incorrect binary form")
|
|
|
|
proc init*(t: typedesc[SkPublicKey],
|
|
data: string): SkPublicKey {.inline.} =
|
|
## Initialize Secp256k1 `public key` from hexadecimal string
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns `public key` on success.
|
|
if not init(result, data):
|
|
raise newException(Secp256k1Error, "Incorrect binary form")
|
|
|
|
proc init*(t: typedesc[SkSignature],
|
|
data: openarray[byte]): SkSignature {.inline.} =
|
|
## Initialize Secp256k1 `signature` from raw binary
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns `signature` on success.
|
|
if not init(result, data):
|
|
raise newException(Secp256k1Error, "Incorrect binary form")
|
|
|
|
proc init*(t: typedesc[SkSignature],
|
|
data: string): SkSignature {.inline.} =
|
|
## Initialize Secp256k1 `signature` from hexadecimal string
|
|
## representation ``data``.
|
|
##
|
|
## Procedure returns `signature` on success.
|
|
if not init(result, data):
|
|
raise newException(Secp256k1Error, "Incorrect binary form")
|
|
|
|
proc getKey*(key: SkPrivateKey): SkPublicKey =
|
|
## Calculate and return Secp256k1 `public key` from `private key` ``key``.
|
|
let ctx = getContext()
|
|
let res = secp256k1_ec_pubkey_create(ctx.context, addr result,
|
|
cast[ptr cuchar](unsafeAddr key))
|
|
if (res != 1) or (len(ctx.error) != 0):
|
|
raiseSecp256k1Error()
|
|
|
|
proc random*(t: typedesc[SkPrivateKey]): SkPrivateKey =
|
|
## Generates new random private key.
|
|
let ctx = getContext()
|
|
while true:
|
|
if randomBytes(result.data) == SkRawPrivateKeySize:
|
|
let res = secp256k1_ec_seckey_verify(ctx.context,
|
|
cast[ptr cuchar](addr result.data[0]))
|
|
if (res == 1) and (len(ctx.error) == 0):
|
|
break
|
|
|
|
proc random*(t: typedesc[SkKeyPair]): SkKeyPair {.inline.} =
|
|
## Generates new random key pair.
|
|
result.seckey = SkPrivateKey.random()
|
|
result.pubkey = result.seckey.getKey()
|
|
|
|
proc toBytes*(key: SkPrivateKey, data: var openarray[byte]): int =
|
|
## Serialize Secp256k1 `private key` ``key`` to raw binary form and store it
|
|
## to ``data``.
|
|
##
|
|
## Procedure returns number of bytes (octets) needed to store
|
|
## Secp256k1 private key.
|
|
result = SkRawPrivateKeySize
|
|
if len(data) >= SkRawPrivateKeySize:
|
|
copyMem(addr data[0], unsafeAddr key.data[0], SkRawPrivateKeySize)
|
|
|
|
proc toBytes*(key: SkPublicKey, data: var openarray[byte]): int =
|
|
## Serialize Secp256k1 `public key` ``key`` to raw binary form and store it
|
|
## to ``data``.
|
|
##
|
|
## Procedure returns number of bytes (octets) needed to store
|
|
## Secp256k1 public key.
|
|
let ctx = getContext()
|
|
var length = csize(len(data))
|
|
result = SkRawPublicKeySize
|
|
if len(data) >= SkRawPublicKeySize:
|
|
let res = secp256k1_ec_pubkey_serialize(ctx.context,
|
|
cast[ptr cuchar](addr data[0]),
|
|
addr length, unsafeAddr key,
|
|
SECP256K1_EC_COMPRESSED)
|
|
|
|
proc toBytes*(sig: SkSignature, data: var openarray[byte]): int =
|
|
## Serialize Secp256k1 `signature` ``sig`` to raw binary form and store it
|
|
## to ``data``.
|
|
##
|
|
## Procedure returns number of bytes (octets) needed to store
|
|
## Secp256k1 signature.
|
|
let ctx = getContext()
|
|
var recid = cint(0)
|
|
result = SkRawSignatureSize
|
|
if len(data) >= SkRawSignatureSize:
|
|
let res = secp256k1_ecdsa_recoverable_signature_serialize_compact(
|
|
ctx.context, cast[ptr cuchar](unsafeAddr data[0]),
|
|
addr recid, unsafeAddr sig)
|
|
if (res == 1) and (len(ctx.error) == 0):
|
|
data[64] = uint8(recid)
|
|
|
|
proc getBytes*(key: SkPrivateKey): seq[byte] {.inline.} =
|
|
## Serialize Secp256k1 `private key` and return it.
|
|
result = @(key.data)
|
|
|
|
proc getBytes*(key: SkPublicKey): seq[byte] {.inline.} =
|
|
## Serialize Secp256k1 `public key` and return it.
|
|
result = newSeq[byte](SkRawPublicKeySize)
|
|
discard toBytes(key, result)
|
|
|
|
proc getBytes*(sig: SkSignature): seq[byte] {.inline.} =
|
|
## Serialize Secp256k1 `signature` and return it.
|
|
result = newSeq[byte](SkRawSignatureSize)
|
|
discard toBytes(sig, result)
|
|
|
|
proc `==`*(ska, skb: SkPrivateKey): bool =
|
|
## Compare Secp256k1 `private key` objects for equality.
|
|
result = (ska.data == skb.data)
|
|
|
|
proc `==`*(pka, pkb: SkPublicKey): bool =
|
|
## Compare Secp256k1 `public key` objects for equality.
|
|
var
|
|
akey: array[SkRawPublicKeySize, byte]
|
|
bkey: array[SkRawPublicKeySize, byte]
|
|
discard pka.toBytes(akey)
|
|
discard pkb.toBytes(bkey)
|
|
result = (akey == bkey)
|
|
|
|
proc `==`*(sia, sib: SkSignature): bool =
|
|
## Compare Secp256k1 `signature` objects for equality.
|
|
var
|
|
asig: array[SkRawSignatureSize, byte]
|
|
bsig: array[SkRawSignatureSize, byte]
|
|
discard sia.toBytes(asig)
|
|
discard sib.toBytes(bsig)
|
|
result = (asig == bsig)
|
|
|
|
proc `$`*(key: SkPrivateKey): string = toHex(key.data)
|
|
## Return string representation of Secp256k1 `private key`.
|
|
|
|
proc `$`*(key: SkPublicKey): string =
|
|
## Return string representation of Secp256k1 `private key`.s
|
|
var spub: array[SkRawPublicKeySize, byte]
|
|
discard key.toBytes(spub)
|
|
result = toHex(spub)
|
|
|
|
proc `$`*(sig: SkSignature): string =
|
|
## Return string representation of Secp256k1 `signature`.s
|
|
var ssig: array[SkRawSignatureSize, byte]
|
|
discard sig.toBytes(ssig)
|
|
result = toHex(ssig)
|
|
|
|
proc sign*[T: byte|char](key: SkPrivateKey, msg: openarray[T]): SkSignature =
|
|
## Sign message `msg` using private key `key` and return signature object.
|
|
let ctx = getContext()
|
|
var hash = sha256.digest(msg)
|
|
let res = secp256k1_ecdsa_sign_recoverable(ctx.context, addr result,
|
|
cast[ptr cuchar](addr hash.data[0]),
|
|
cast[ptr cuchar](unsafeAddr key),
|
|
nil, nil)
|
|
if (res != 1) or (len(ctx.error) != 0):
|
|
raiseSecp256k1Error()
|
|
|
|
proc verify*[T: byte|char](sig: SkSignature, msg: openarray[T],
|
|
key: SkPublicKey): bool =
|
|
var pubkey: SkPublicKey
|
|
let ctx = getContext()
|
|
var hash = sha256.digest(msg)
|
|
let res = secp256k1_ecdsa_recover(ctx.context, addr pubkey, unsafeAddr sig,
|
|
cast[ptr cuchar](addr hash.data[0]))
|
|
if (res == 1) and (len(ctx.error) == 0):
|
|
if key == pubkey:
|
|
result = true
|
|
|
|
proc clear*(key: var SkPrivateKey) {.inline.} =
|
|
## Wipe and clear memory of Secp256k1 `private key`.
|
|
burnMem(key.data)
|
|
|
|
proc clear*(key: var SkPublicKey) {.inline.} =
|
|
## Wipe and clear memory of Secp256k1 `public key`.
|
|
burnMem(addr key, SkRawPrivateKeySize * 2)
|
|
|
|
proc clear*(sig: var SkSignature) {.inline.} =
|
|
## Wipe and clear memory of Secp256k1 `signature`.
|
|
# Internal memory representation size of signature object is 64 bytes.
|
|
burnMem(addr sig, SkRawPrivateKeySize * 2)
|
|
|
|
proc clear*(pair: var SkKeyPair) {.inline.} =
|
|
## Wipe and clear memory of Secp256k1 `key pair`.
|
|
pair.seckey.clear()
|
|
pair.pubkey.clear()
|