wip: integrating secio

This commit is contained in:
cheatfate 2019-09-13 11:20:37 -06:00 committed by Dmitriy Ryajov
parent 9b5f75a100
commit 2d00f6a6db
1 changed files with 354 additions and 31 deletions

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@ -6,9 +6,16 @@
## at your option. ## at your option.
## This file may not be copied, modified, or distributed except according to ## This file may not be copied, modified, or distributed except according to
## those terms. ## those terms.
import chronos, chronicles
import nimcrypto/[sysrand, hmac, sha2, sha, hash, rijndael, twofish, bcmode]
import secure,
../../connection,
../../crypto/crypto,
../../crypto/ecnist,
../../protobuf/minprotobuf,
../../peer
import chronos, chronicles, nimcrypto/sysrand export hmac, sha2, sha, hash, rijndael, bcmode
import secure, ../../connection, ../../crypto/crypto
logScope: logScope:
topic = "secio" topic = "secio"
@ -16,63 +23,380 @@ logScope:
const const
SecioCodec* = "/secio/1.0.0" SecioCodec* = "/secio/1.0.0"
SecioMaxMessageSize = 8 * 1024 * 1024 ## 8mb SecioMaxMessageSize = 8 * 1024 * 1024 ## 8mb
SecioMaxMacSize = sha512.sizeDigest
SecioNonceSize = 16 SecioNonceSize = 16
SecioExchanges = "P-256,P-384,P-521" SecioExchanges = "P-256,P-384,P-521"
SecioCiphers = "AES-256,AES-128" SecioCiphers = "TwofishCTR,AES-256,AES-128"
SecioHashes = "SHA-256,SHA-512" SecioHashes = "SHA256,SHA512"
type type
Secio = ref object of Secure Secio = ref object of Secure
localPrivateKey: PrivateKey
localPublicKey: PublicKey localPublicKey: PublicKey
remotePublicKey: PublicKey
SecureCipherType {.pure.} = enum
Aes128, Aes256, Twofish
SecureMacType {.pure.} = enum
Sha1, Sha256, Sha512
SecureCipher = object
case kind: SecureCipherType
of SecureCipherType.Aes128:
ctxaes128: CTR[aes128]
of SecureCipherType.Aes256:
ctxaes256: CTR[aes256]
of SecureCipherType.Twofish:
ctxtwofish256: CTR[twofish256]
SecureMac = object
case kind: SecureMacType
of SecureMacType.Sha256:
ctxsha256: HMAC[sha256]
of SecureMacType.Sha512:
ctxsha512: HMAC[sha512]
of SecureMacType.Sha1:
ctxsha1: HMAC[sha1]
SecureConnection* = ref object of BufferStream
writerMac: SecureMac
readerMac: SecureMac
writerCoder: SecureCipher
readerCoder: SecureCipher
proc init(mac: var SecureMac, hash: string, key: openarray[byte]) =
if hash == "SHA256":
mac = SecureMac(kind: SecureMacType.Sha256)
mac.ctxsha256.init(key)
elif hash == "SHA512":
mac = SecureMac(kind: SecureMacType.Sha512)
mac.ctxsha512.init(key)
elif hash == "SHA1":
mac = SecureMac(kind: SecureMacType.Sha1)
mac.ctxsha1.init(key)
proc update(mac: var SecureMac, data: openarray[byte]) =
case mac.kind
of SecureMacType.Sha256:
update(mac.ctxsha256, data)
of SecureMacType.Sha512:
update(mac.ctxsha512, data)
of SecureMacType.Sha1:
update(mac.ctxsha1, data)
proc sizeDigest(mac: SecureMac): int {.inline.} =
case mac.kind
of SecureMacType.Sha256:
result = int(mac.ctxsha256.sizeDigest())
of SecureMacType.Sha512:
result = int(mac.ctxsha512.sizeDigest())
of SecureMacType.Sha1:
result = int(mac.ctxsha1.sizeDigest())
proc finish(mac: var SecureMac, data: var openarray[byte]) =
case mac.kind
of SecureMacType.Sha256:
discard finish(mac.ctxsha256, data)
of SecureMacType.Sha512:
discard finish(mac.ctxsha512, data)
of SecureMacType.Sha1:
discard finish(mac.ctxsha1, data)
proc reset(mac: var SecureMac) =
case mac.kind
of SecureMacType.Sha256:
reset(mac.ctxsha256)
of SecureMacType.Sha512:
reset(mac.ctxsha512)
of SecureMacType.Sha1:
reset(mac.ctxsha1)
proc init(sc: var SecureCipher, cipher: string, key: openarray[byte],
iv: openarray[byte]) {.inline.} =
if cipher == "AES-128":
sc = SecureCipher(kind: SecureCipherType.Aes128)
sc.ctxaes128.init(key, iv)
elif cipher == "AES-256":
sc = SecureCipher(kind: SecureCipherType.Aes256)
sc.ctxaes256.init(key, iv)
elif cipher == "TwofishCTR":
sc = SecureCipher(kind: SecureCipherType.Twofish)
sc.ctxtwofish256.init(key, iv)
proc encrypt(cipher: var SecureCipher, input: openarray[byte],
output: var openarray[byte]) {.inline.} =
case cipher.kind
of SecureCipherType.Aes128:
cipher.ctxaes128.encrypt(input, output)
of SecureCipherType.Aes256:
cipher.ctxaes256.encrypt(input, output)
of SecureCipherType.Twofish:
cipher.ctxtwofish256.encrypt(input, output)
proc decrypt(cipher: var SecureCipher, input: openarray[byte],
output: var openarray[byte]) {.inline.} =
case cipher.kind
of SecureCipherType.Aes128:
cipher.ctxaes128.decrypt(input, output)
of SecureCipherType.Aes256:
cipher.ctxaes256.decrypt(input, output)
of SecureCipherType.Twofish:
cipher.ctxtwofish256.decrypt(input, output)
proc macCheckAndDecode(sconn: SecureConnection, data: var seq[byte]): bool =
## This procedure checks MAC of recieved message ``data`` and if message is
## authenticated, then decrypt message.
##
## Procedure returns ``false`` if message is too short or MAC verification
## failed.
var macData: array[SecioMaxMacSize, byte]
let macsize = sconn.readerMac.sizeDigest()
if len(data) < macsize:
trace "Message is shorter then MAC size", message_length = len(data),
mac_size = macsize
return false
let mark = len(data) - macsize
sconn.readerMac.update(data.toOpenArray(0, mark - 1))
sconn.readerMac.finish(macData)
sconn.readerMac.reset()
if not equalMem(addr data[mark], addr macData[0], macsize):
trace "Invalid MAC",
calculated = toHex(macData.toOpenArray(0, macsize - 1)),
stored = toHex(data.toOpenArray(mark, len(data) - 1))
return false
sconn.readerCoder.decrypt(data.toOpenArray(0, mark - 1),
data.toOpenArray(0, mark - 1))
data.setLen(mark)
result = true
proc readMessage*(sconn: SecureConnection): Future[seq[byte]] {.async.} =
## Read message from channel secure connection ``sconn``.
try:
var buf = newSeq[byte](4)
await sconn.conn.readExactly(addr buf[0], 4)
let length = (int(buf[0]) shl 24) or (int(buf[1]) shl 16) or
(int(buf[2]) shl 8) or (int(buf[3]))
trace "Recieved message header", header = toHex(buf), length = length
if length <= SecioMaxMessageSize:
buf.setLen(length)
await sconn.conn.readExactly(addr buf[0], length)
trace "Received message body", length = length,
buffer = toHex(buf)
if sconn.macCheckAndDecode(buf):
result = buf
else:
debug "Message MAC verification failed"
else:
debug "Received message header size is more then allowed",
length = length, allowed_length = SecioMaxMessageSize
except AsyncStreamIncompleteError:
debug "Connection dropped while reading"
except AsyncStreamReadError:
debug "Error reading from connection"
proc writeMessage*(sconn: SecureConnection, message: seq[byte]) {.async.} =
## Write message ``message`` to secure connection ``sconn``.
let macsize = sconn.writerMac.sizeDigest()
var msg = newSeq[byte](len(message) + 4 + macsize)
sconn.writerCoder.encrypt(message, msg.toOpenArray(4, 4 + len(message) - 1))
let mo = 4 + len(message)
sconn.writerMac.update(msg.toOpenArray(4, 4 + len(message) - 1))
sconn.writerMac.finish(msg.toOpenArray(mo, mo + macsize - 1))
sconn.writerMac.reset()
let length = len(message) + macsize
msg[0] = byte(length shr 24)
msg[1] = byte(length shr 16)
msg[2] = byte(length shr 8)
msg[3] = byte(length and 0xFF)
trace "Writing message", message = toHex(msg)
try:
await sconn.pushTo(msg)
except AsyncStreamWriteError:
debug "Could not write to connection"
proc newSecureConnection*(conn: Connection, hash: string, cipher: string,
secrets: Secret,
order: int): SecureConnection =
## Create new secure connection, using specified hash algorithm ``hash``,
## cipher algorithm ``cipher``, stretched keys ``secrets`` and order
## ``order``.
new result
let i0 = if order < 0: 1 else: 0
let i1 = if order < 0: 0 else: 1
result.conn = conn
trace "Writer credentials", mackey = toHex(secrets.macOpenArray(i0)),
enckey = toHex(secrets.keyOpenArray(i0)),
iv = toHex(secrets.ivOpenArray(i0))
trace "Reader credentials", mackey = toHex(secrets.macOpenArray(i1)),
enckey = toHex(secrets.keyOpenArray(i1)),
iv = toHex(secrets.ivOpenArray(i1))
result.writerMac.init(hash, secrets.macOpenArray(i0))
result.readerMac.init(hash, secrets.macOpenArray(i1))
result.writerCoder.init(cipher, secrets.keyOpenArray(i0),
secrets.ivOpenArray(i0))
result.readerCoder.init(cipher, secrets.keyOpenArray(i1),
secrets.ivOpenArray(i1))
proc transactMessage(conn: Connection, proc transactMessage(conn: Connection,
msg: seq[byte]): Future[seq[byte]] {.async.} = msg: seq[byte]): Future[seq[byte]] {.async.} =
var buf = newSeq[byte](4) var buf = newSeq[byte](4)
try: try:
debug "Sending proposal", message = toHex(msg) trace "Sending message", message = toHex(msg), length = len(msg)
await conn.write(msg) await conn.write(msg)
await conn.readExactly(addr buf[0], 4) await conn.readExactly(addr buf[0], 4)
let length = (int(buf[0]) shl 24) or (int(buf[1]) shl 16) or let length = (int(buf[0]) shl 24) or (int(buf[1]) shl 16) or
(int(buf[2]) shl 8) or (int(buf[3])) (int(buf[2]) shl 8) or (int(buf[3]))
debug "Recieved message header", header = toHex(buf), length = length trace "Recieved message header", header = toHex(buf), length = length
if length <= SecioMaxMessageSize: if length <= SecioMaxMessageSize:
buf.setLen(length) buf.setLen(length)
await conn.readExactly(addr buf[0], length) await conn.readExactly(addr buf[0], length)
debug "Received message body", conn = conn, length = length trace "Received message body", conn = conn, length = length
result = buf result = buf
else: else:
debug "Received size of message exceed limits", conn = conn, trace "Received size of message exceed limits", conn = conn,
length = length length = length
except AsyncStreamIncompleteError: except AsyncStreamIncompleteError:
debug "Connection dropped while reading", conn = conn trace "Connection dropped while reading", conn = conn
except AsyncStreamReadError: except AsyncStreamReadError:
debug "Error reading from connection", conn = conn trace "Error reading from connection", conn = conn
except AsyncStreamWriteError: except AsyncStreamWriteError:
debug "Could not write to connection", conn = conn trace "Could not write to connection", conn = conn
proc handshake*(p: Secio, conn: Connection) {.async.} = proc handshake*(p: Secio, conn: Connection) {.async.} =
var nonce: array[SecioNonceSize, byte] var
var pk = p.localPublicKey.getBytes() localNonce: array[SecioNonceSize, byte]
echo toHex(pk) remoteNonce: seq[byte]
if randomBytes(nonce) != SecioNonceSize: remoteBytesPubkey: seq[byte]
remoteEBytesPubkey: seq[byte]
remoteEBytesSig: seq[byte]
remotePubkey: PublicKey
remoteEPubkey: PublicKey = PublicKey(scheme: ECDSA)
remoteESignature: Signature
remoteExchanges: string
remoteCiphers: string
remoteHashes: string
remotePeerId: PeerID
localPeerId: PeerID
ekey: PrivateKey
localBytesPubkey = p.localPublicKey.getBytes()
if randomBytes(localNonce) != SecioNonceSize:
raise newException(CatchableError, "Could not generate random data") raise newException(CatchableError, "Could not generate random data")
var request = createProposal(localNonce, localBytesPubkey, SecioExchanges,
SecioCiphers, SecioHashes)
localPeerId = PeerID.init(p.localPublicKey)
debug "Local proposal", schemes = SecioExchanges, ciphers = SecioCiphers, debug "Local proposal", schemes = SecioExchanges, ciphers = SecioCiphers,
hashes = SecioHashes, nonce = toHex(nonce), hashes = SecioHashes,
pubkey = toHex(pk) pubkey = toHex(localBytesPubkey),
peer = localPeerId
echo "local proposal" var answer = await transactMessage(conn, request)
var answer = await transactMessage(conn,
createProposal(nonce, pk, SecioExchanges, SecioCiphers, SecioHashes)
)
echo toHex(answer)
if len(answer) == 0: if len(answer) == 0:
debug "Proposal exchange failed", conn = conn trace "Proposal exchange failed", conn = conn
return return
if not decodeProposal(answer, remoteNonce, remoteBytesPubkey, remoteExchanges,
remoteCiphers, remoteHashes):
trace "Remote proposal decoding failed", conn = conn
return
if not remotePubkey.init(remoteBytesPubkey):
trace "Remote public key incorrect or corrupted", pubkey = remoteBytesPubkey
return
remotePeerId = PeerID.init(remotePubkey)
# TODO: PeerID check against supplied PeerID
let order = getOrder(remoteBytesPubkey, localNonce, localBytesPubkey,
remoteNonce)
debug "Remote proposal", schemes = remoteExchanges, ciphers = remoteCiphers,
hashes = remoteHashes,
pubkey = toHex(remoteBytesPubkey), order = order,
peer = remotePeerId
let scheme = selectBest(order, SecioExchanges, remoteExchanges)
let cipher = selectBest(order, SecioCiphers, remoteCiphers)
let hash = selectBest(order, SecioHashes, remoteHashes)
if len(scheme) == 0 or len(cipher) == 0 or len(hash) == 0:
debug "No algorithms in common", peer = remotePeerId
return
debug "Encryption scheme selected", scheme = scheme, cipher = cipher,
hash = hash
var ekeypair = ephemeral(scheme)
# We need EC public key in raw binary form
var epubkey = ekeypair.pubkey.eckey.getRawBytes()
var localCorpus = request[4..^1] & answer & epubkey
var signature = p.localPrivateKey.sign(localCorpus)
var localExchange = createExchange(epubkey, signature.getBytes())
var remoteExchange = await transactMessage(conn, localExchange)
if len(remoteExchange) == 0:
trace "Corpus exchange failed", conn = conn
return
if not decodeExchange(remoteExchange, remoteEBytesPubkey, remoteEBytesSig):
trace "Remote exchange decoding failed", conn = conn
return
if not remoteESignature.init(remoteEBytesSig):
trace "Remote signature incorrect or corrupted",
signature = toHex(remoteEBytesSig)
return
var remoteCorpus = answer & request[4..^1] & remoteEBytesPubkey
if not remoteESignature.verify(remoteCorpus, remotePubkey):
debug "Signature verification failed", scheme = remotePubkey.scheme,
signature = remoteESignature, pubkey = remotePubkey,
corpus = remoteCorpus
return
debug "Signature verified", scheme = remotePubkey.scheme
if not remoteEPubkey.eckey.initRaw(remoteEBytesPubkey):
debug "Remote ephemeral public key incorrect or corrupted",
pubkey = toHex(remoteEBytesPubkey)
return
var secret = getSecret(remoteEPubkey, ekeypair.seckey)
if len(secret) == 0:
trace "Shared secret could not be created",
pubkeyScheme = remoteEPubkey.scheme,
seckeyScheme = ekeypair.seckey.scheme
return
trace "Shared secret calculated", secret = toHex(secret)
var keys = stretchKeys(cipher, hash, secret)
trace "Authenticated encryption parameters",
iv0 = toHex(keys.ivOpenArray(0)), key0 = toHex(keys.keyOpenArray(0)),
mac0 = toHex(keys.macOpenArray(0)),
iv1 = toHex(keys.ivOpenArray(1)), key1 = toHex(keys.keyOpenArray(1)),
mac1 = toHex(keys.macOpenArray(1))
# Perform Nonce exchange over encrypted channel.
var sconn = newSecureConnection(conn, hash, cipher, keys, order)
await sconn.writeMessage(remoteNonce)
var res = await sconn.readMessage()
if res != @localNonce:
debug "Nonce verification failed", receivedNonce = toHex(res),
localNonce = toHex(localNonce)
else:
debug "Secure handshake succeeded"
method init(p: Secio) {.gcsafe.} = method init(p: Secio) {.gcsafe.} =
proc handle(conn: Connection, proto: string) {.async, gcsafe.} = proc handle(conn: Connection, proto: string) {.async, gcsafe.} =
echo "HERE" echo "HERE"
@ -81,11 +405,10 @@ method init(p: Secio) {.gcsafe.} =
p.handler = handle p.handler = handle
method secure*(p: Secio, conn: Connection): Future[Connection] {.async, gcsafe.} = method secure*(p: Secio, conn: Connection): Future[Connection] {.async, gcsafe.} =
echo "handshaking"
await p.handshake(conn) await p.handshake(conn)
proc newSecio*(localPublicKey: PublicKey): Secio = proc newSecio*(localPrivateKey: PrivateKey): Secio =
new result new result
result.localPublicKey = localPublicKey result.localPrivateKey = localPrivateKey
result.localPublicKey = localPrivateKey.getKey()
result.init() result.init()