void SshKeyExchange::sendNewKeysPacket(const SshIncomingPacket &dhReply,
const QByteArray &clientId)
{
const SshKeyExchangeReply &reply
= dhReply.extractKeyExchangeReply(m_serverHostKeyAlgo);
if (reply.f <= 0 || reply.f >= m_dhKey->group_p()) {
throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
"Server sent invalid f.");
}
QByteArray concatenatedData = AbstractSshPacket::encodeString(clientId);
concatenatedData += AbstractSshPacket::encodeString(m_serverId);
concatenatedData += AbstractSshPacket::encodeString(m_clientKexInitPayload);
concatenatedData += AbstractSshPacket::encodeString(m_serverKexInitPayload);
concatenatedData += reply.k_s;
concatenatedData += AbstractSshPacket::encodeMpInt(m_dhKey->get_y());
concatenatedData += AbstractSshPacket::encodeMpInt(reply.f);
SymmetricKey k = m_dhKey->derive_key(reply.f);
m_k = AbstractSshPacket::encodeMpInt(BigInt(k.begin(), k.length()));
concatenatedData += m_k;
m_hash.reset(get_hash(botanSha1Name()));
const SecureVector<byte> &hashResult
= m_hash->process(convertByteArray(concatenatedData),
concatenatedData.size());
m_h = convertByteArray(hashResult);
QScopedPointer<Public_Key> sigKey;
QScopedPointer<PK_Verifier> verifier;
if (m_serverHostKeyAlgo == SshCapabilities::PubKeyDss) {
const DL_Group group(reply.parameters.at(0), reply.parameters.at(1),
reply.parameters.at(2));
DSA_PublicKey * const dsaKey
= new DSA_PublicKey(group, reply.parameters.at(3));
sigKey.reset(dsaKey);
verifier.reset(get_pk_verifier(*dsaKey,
botanEmsaAlgoName(SshCapabilities::PubKeyDss)));
} else if (m_serverHostKeyAlgo == SshCapabilities::PubKeyRsa) {
RSA_PublicKey * const rsaKey
= new RSA_PublicKey(reply.parameters.at(1), reply.parameters.at(0));
sigKey.reset(rsaKey);
verifier.reset(get_pk_verifier(*rsaKey,
botanEmsaAlgoName(SshCapabilities::PubKeyRsa)));
} else {
Q_ASSERT(!"Impossible: Neither DSS nor RSA!");
}
const byte * const botanH = convertByteArray(m_h);
const Botan::byte * const botanSig
= convertByteArray(reply.signatureBlob);
if (!verifier->verify_message(botanH, m_h.size(), botanSig,
reply.signatureBlob.size())) {
throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
"Invalid signature in SSH_MSG_KEXDH_REPLY packet.");
}
m_sendFacility.sendNewKeysPacket();
}
void SshKeyExchange::sendNewKeysPacket(const SshIncomingPacket &dhReply,
const QByteArray &clientId)
{
const SshKeyExchangeReply &reply
= dhReply.extractKeyExchangeReply(m_serverHostKeyAlgo);
if (m_dhKey && (reply.f <= 0 || reply.f >= m_dhKey->group_p())) {
throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
"Server sent invalid f.");
}
QByteArray concatenatedData = AbstractSshPacket::encodeString(clientId);
concatenatedData += AbstractSshPacket::encodeString(m_serverId);
concatenatedData += AbstractSshPacket::encodeString(m_clientKexInitPayload);
concatenatedData += AbstractSshPacket::encodeString(m_serverKexInitPayload);
concatenatedData += reply.k_s;
SecureVector<byte> encodedK;
if (m_dhKey) {
concatenatedData += AbstractSshPacket::encodeMpInt(m_dhKey->get_y());
concatenatedData += AbstractSshPacket::encodeMpInt(reply.f);
DH_KA_Operation dhOp(*m_dhKey);
SecureVector<byte> encodedF = BigInt::encode(reply.f);
encodedK = dhOp.agree(encodedF, encodedF.size());
} else {
Q_ASSERT(m_ecdhKey);
concatenatedData // Q_C.
+= AbstractSshPacket::encodeString(convertByteArray(m_ecdhKey->public_value()));
concatenatedData += AbstractSshPacket::encodeString(reply.q_s);
ECDH_KA_Operation ecdhOp(*m_ecdhKey);
encodedK = ecdhOp.agree(convertByteArray(reply.q_s), reply.q_s.count());
}
const BigInt k = BigInt::decode(encodedK);
m_k = AbstractSshPacket::encodeMpInt(k); // Roundtrip, as Botan encodes BigInts somewhat differently.
concatenatedData += m_k;
m_hash.reset(get_hash(botanHMacAlgoName(hashAlgoForKexAlgo())));
const SecureVector<byte> &hashResult = m_hash->process(convertByteArray(concatenatedData),
concatenatedData.size());
m_h = convertByteArray(hashResult);
#ifdef CREATOR_SSH_DEBUG
printData("Client Id", AbstractSshPacket::encodeString(clientId));
printData("Server Id", AbstractSshPacket::encodeString(m_serverId));
printData("Client Payload", AbstractSshPacket::encodeString(m_clientKexInitPayload));
printData("Server payload", AbstractSshPacket::encodeString(m_serverKexInitPayload));
printData("K_S", reply.k_s);
printData("y", AbstractSshPacket::encodeMpInt(m_dhKey->get_y()));
printData("f", AbstractSshPacket::encodeMpInt(reply.f));
printData("K", m_k);
printData("Concatenated data", concatenatedData);
printData("H", m_h);
#endif // CREATOR_SSH_DEBUG
QScopedPointer<Public_Key> sigKey;
if (m_serverHostKeyAlgo == SshCapabilities::PubKeyDss) {
const DL_Group group(reply.parameters.at(0), reply.parameters.at(1),
reply.parameters.at(2));
DSA_PublicKey * const dsaKey
= new DSA_PublicKey(group, reply.parameters.at(3));
sigKey.reset(dsaKey);
} else if (m_serverHostKeyAlgo == SshCapabilities::PubKeyRsa) {
RSA_PublicKey * const rsaKey
= new RSA_PublicKey(reply.parameters.at(1), reply.parameters.at(0));
sigKey.reset(rsaKey);
} else if (m_serverHostKeyAlgo == SshCapabilities::PubKeyEcdsa) {
const PointGFp point = OS2ECP(convertByteArray(reply.q), reply.q.count(),
m_ecdhKey->domain().get_curve());
ECDSA_PublicKey * const ecdsaKey = new ECDSA_PublicKey(m_ecdhKey->domain(), point);
sigKey.reset(ecdsaKey);
} else {
Q_ASSERT(!"Impossible: Neither DSS nor RSA nor ECDSA!");
}
const byte * const botanH = convertByteArray(m_h);
const Botan::byte * const botanSig = convertByteArray(reply.signatureBlob);
PK_Verifier verifier(*sigKey, botanEmsaAlgoName(m_serverHostKeyAlgo));
if (!verifier.verify_message(botanH, m_h.size(), botanSig, reply.signatureBlob.size())) {
throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
"Invalid signature in key exchange reply packet.");
}
checkHostKey(reply.k_s);
m_sendFacility.sendNewKeysPacket();
m_dhKey.reset(nullptr);
m_ecdhKey.reset(nullptr);
}
void SshKeyExchange::sendNewKeysPacket(const SshIncomingPacket &dhReply,
const QByteArray &clientId)
{
const SshKeyExchangeReply &reply
= dhReply.extractKeyExchangeReply(m_serverHostKeyAlgo);
if (reply.f <= 0 || reply.f >= m_dhKey->group_p()) {
throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
"Server sent invalid f.");
}
QByteArray concatenatedData = AbstractSshPacket::encodeString(clientId);
concatenatedData += AbstractSshPacket::encodeString(m_serverId);
concatenatedData += AbstractSshPacket::encodeString(m_clientKexInitPayload);
concatenatedData += AbstractSshPacket::encodeString(m_serverKexInitPayload);
concatenatedData += reply.k_s;
concatenatedData += AbstractSshPacket::encodeMpInt(m_dhKey->get_y());
concatenatedData += AbstractSshPacket::encodeMpInt(reply.f);
const BigInt k = power_mod(reply.f, m_dhKey->get_x(), m_dhKey->get_domain().get_p());
m_k = AbstractSshPacket::encodeMpInt(k);
concatenatedData += m_k;
m_hash.reset(get_hash(botanSha1Name()));
const SecureVector<byte> &hashResult
= m_hash->process(convertByteArray(concatenatedData),
concatenatedData.size());
m_h = convertByteArray(hashResult);
#ifdef CREATOR_SSH_DEBUG
printData("Client Id", AbstractSshPacket::encodeString(clientId));
printData("Server Id", AbstractSshPacket::encodeString(m_serverId));
printData("Client Payload", AbstractSshPacket::encodeString(m_clientKexInitPayload));
printData("Server payload", AbstractSshPacket::encodeString(m_serverKexInitPayload));
printData("K_S", reply.k_s);
printData("y", AbstractSshPacket::encodeMpInt(m_dhKey->get_y()));
printData("f", AbstractSshPacket::encodeMpInt(reply.f));
printData("K", m_k);
printData("Concatenated data", concatenatedData);
printData("H", m_h);
#endif // CREATOR_SSH_DEBUG
QSharedPointer<Public_Key> publicKey;
QByteArray algorithm;
if (m_serverHostKeyAlgo == SshCapabilities::PubKeyDss) {
const DL_Group group(reply.parameters.at(0), reply.parameters.at(1),
reply.parameters.at(2));
publicKey = createDsaPublicKey(group, reply.parameters.at(3));
algorithm = SshCapabilities::PubKeyDss;
} else if (m_serverHostKeyAlgo == SshCapabilities::PubKeyRsa) {
publicKey = createRsaPublicKey(reply.parameters.at(1), reply.parameters.at(0));
algorithm = SshCapabilities::PubKeyRsa;
} else {
Q_ASSERT(!"Impossible: Neither DSS nor RSA!");
}
const byte * const botanH = convertByteArray(m_h);
const Botan::byte * const botanSig
= convertByteArray(reply.signatureBlob);
if (!PK_Verifier(*publicKey, botanEmsaAlgoName(algorithm)).verify_message(botanH, m_h.size(),
botanSig, reply.signatureBlob.size())) {
throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
"Invalid signature in SSH_MSG_KEXDH_REPLY packet.");
}
m_sendFacility.sendNewKeysPacket();
}
