C++ SymmetricKey::length方法代码示例

void XTS_Decryption::set_key(const SymmetricKey& key)
   {
   u32bit key_half = key.length() / 2;

   if(key.length() % 2 == 1 || !cipher->valid_keylength(key_half))
      throw Invalid_Key_Length(name(), key.length());

   cipher->set_key(key.begin(), key_half);
   cipher2->set_key(key.begin() + key_half, key_half);
   }

bool ne7ssh_crypt::makeKexSecret (Botan::SecureVector<Botan::byte> &result, Botan::BigInt &f)
{
    PK_Key_Agreement key_agreement(*privKexKey, "Raw");
    SymmetricKey negotiated = key_agreement.derive_key(32, (byte*)f.data(), f.bytes(), "");
//  SymmetricKey negotiated = privKexKey->derive_key (f);
  if (!negotiated.length()) return false;

  BigInt Kint (negotiated.begin(), negotiated.length());  
  ne7ssh_string::bn2vector(result, Kint);
  K = Botan::SecureVector<Botan::byte>(result);
  delete privKexKey;
  privKexKey = 0;
  return true;
}  

void Transform_Filter::set_key(const SymmetricKey& key)
   {
   if(Keyed_Transform* keyed = dynamic_cast<Keyed_Transform*>(m_transform.get()))
      keyed->set_key(key);
   else if(key.length() != 0)
      throw std::runtime_error("Transform " + name() + " does not accept keys");
   }

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();
}

SecureVector<byte> rfc3394_keyunwrap(const MemoryRegion<byte>& key,
                                     const SymmetricKey& kek,
                                     Algorithm_Factory& af)
   {
   if(key.size() < 16 || key.size() % 8 != 0)
      throw std::invalid_argument("Bad input key size for NIST key unwrap");

   std::auto_ptr<BlockCipher> aes(make_aes(kek.length(), af));
   aes->set_key(kek);

   const size_t n = (key.size() - 8) / 8;

   SecureVector<byte> R(n * 8);
   SecureVector<byte> A(16);

   for(size_t i = 0; i != 8; ++i)
      A[i] = key[i];

   copy_mem(&R[0], key.begin() + 8, key.size() - 8);

   for(size_t j = 0; j <= 5; ++j)
      {
      for(size_t i = n; i != 0; --i)
         {
         const u32bit t = (5 - j) * n + i;

         byte t_buf[4] = { 0 };
         store_be(t, t_buf);

         xor_buf(&A[4], &t_buf[0], 4);

         copy_mem(&A[8], &R[8*(i-1)], 8);

         aes->decrypt(&A[0]);

         copy_mem(&R[8*(i-1)], &A[8], 8);
         }
      }

   if(load_be<u64bit>(&A[0], 0) != 0xA6A6A6A6A6A6A6A6)
      throw Integrity_Failure("NIST key unwrap failed");

   return R;
   }

/*
* Create a new Client Key Exchange message
*/
Client_Key_Exchange::Client_Key_Exchange(Handshake_IO& io,
                                         Handshake_State& state,
                                         const Policy& policy,
                                         Credentials_Manager& creds,
                                         const Public_Key* server_public_key,
                                         const std::string& hostname,
                                         RandomNumberGenerator& rng)
   {
   const std::string kex_algo = state.ciphersuite().kex_algo();

   if(kex_algo == "PSK")
      {
      std::string identity_hint = "";

      if(state.server_kex())
         {
         TLS_Data_Reader reader("ClientKeyExchange", state.server_kex()->params());
         identity_hint = reader.get_string(2, 0, 65535);
         }

      const std::string psk_identity = creds.psk_identity("tls-client",
                                                          hostname,
                                                          identity_hint);

      append_tls_length_value(m_key_material, psk_identity, 2);

      SymmetricKey psk = creds.psk("tls-client", hostname, psk_identity);

      std::vector<byte> zeros(psk.length());

      append_tls_length_value(m_pre_master, zeros, 2);
      append_tls_length_value(m_pre_master, psk.bits_of(), 2);
      }
   else if(state.server_kex())
      {
      TLS_Data_Reader reader("ClientKeyExchange", state.server_kex()->params());

      SymmetricKey psk;

      if(kex_algo == "DHE_PSK" || kex_algo == "ECDHE_PSK")
         {
         std::string identity_hint = reader.get_string(2, 0, 65535);

         const std::string psk_identity = creds.psk_identity("tls-client",
                                                             hostname,
                                                             identity_hint);

         append_tls_length_value(m_key_material, psk_identity, 2);

         psk = creds.psk("tls-client", hostname, psk_identity);
         }

      if(kex_algo == "DH" || kex_algo == "DHE_PSK")
         {
         BigInt p = BigInt::decode(reader.get_range<byte>(2, 1, 65535));
         BigInt g = BigInt::decode(reader.get_range<byte>(2, 1, 65535));
         BigInt Y = BigInt::decode(reader.get_range<byte>(2, 1, 65535));

         if(reader.remaining_bytes())
            throw Decoding_Error("Bad params size for DH key exchange");

         if(p.bits() < policy.minimum_dh_group_size())
            throw TLS_Exception(Alert::INSUFFICIENT_SECURITY,
                                "Server sent DH group of " +
                                std::to_string(p.bits()) +
                                " bits, policy requires at least " +
                                std::to_string(policy.minimum_dh_group_size()));

         /*
         * A basic check for key validity. As we do not know q here we
         * cannot check that Y is in the right subgroup. However since
         * our key is ephemeral there does not seem to be any
         * advantage to bogus keys anyway.
         */
         if(Y <= 1 || Y >= p - 1)
            throw TLS_Exception(Alert::INSUFFICIENT_SECURITY,
                                "Server sent bad DH key for DHE exchange");

         DL_Group group(p, g);

         if(!group.verify_group(rng, false))
            throw TLS_Exception(Alert::INSUFFICIENT_SECURITY,
                                "DH group validation failed");

         DH_PublicKey counterparty_key(group, Y);

         DH_PrivateKey priv_key(rng, group);

         PK_Key_Agreement ka(priv_key, "Raw");

         secure_vector<byte> dh_secret = CT::strip_leading_zeros(
            ka.derive_key(0, counterparty_key.public_value()).bits_of());

         if(kex_algo == "DH")
            m_pre_master = dh_secret;
         else
            {
//.........这里部分代码省略.........

/*
* Read a Client Key Exchange message
*/
Client_Key_Exchange::Client_Key_Exchange(const std::vector<byte>& contents,
                                         const Handshake_State& state,
                                         const Private_Key* server_rsa_kex_key,
                                         Credentials_Manager& creds,
                                         const Policy& policy,
                                         RandomNumberGenerator& rng)
   {
   const std::string kex_algo = state.ciphersuite().kex_algo();

   if(kex_algo == "RSA")
      {
      BOTAN_ASSERT(state.server_certs() && !state.server_certs()->cert_chain().empty(),
                   "RSA key exchange negotiated so server sent a certificate");

      if(!server_rsa_kex_key)
         throw Internal_Error("Expected RSA kex but no server kex key set");

      if(!dynamic_cast<const RSA_PrivateKey*>(server_rsa_kex_key))
         throw Internal_Error("Expected RSA key but got " + server_rsa_kex_key->algo_name());

      PK_Decryptor_EME decryptor(*server_rsa_kex_key, "PKCS1v15");

      Protocol_Version client_version = state.client_hello()->version();

      /*
      * This is used as the pre-master if RSA decryption fails.
      * Otherwise we can be used as an oracle. See Bleichenbacher
      * "Chosen Ciphertext Attacks against Protocols Based on RSA
      * Encryption Standard PKCS #1", Crypto 98
      *
      * Create it here instead if in the catch clause as otherwise we
      * expose a timing channel WRT the generation of the fake value.
      * Some timing channel likely remains due to exception handling
      * and the like.
      */
      secure_vector<byte> fake_pre_master = rng.random_vec(48);
      fake_pre_master[0] = client_version.major_version();
      fake_pre_master[1] = client_version.minor_version();

      try
         {
         TLS_Data_Reader reader("ClientKeyExchange", contents);
         m_pre_master = decryptor.decrypt(reader.get_range<byte>(2, 0, 65535));

         if(m_pre_master.size() != 48 ||
            client_version.major_version() != m_pre_master[0] ||
            client_version.minor_version() != m_pre_master[1])
            {
            throw Decoding_Error("Client_Key_Exchange: Secret corrupted");
            }
         }
      catch(...)
         {
         m_pre_master = fake_pre_master;
         }
      }
   else
      {
      TLS_Data_Reader reader("ClientKeyExchange", contents);

      SymmetricKey psk;

      if(kex_algo == "PSK" || kex_algo == "DHE_PSK" || kex_algo == "ECDHE_PSK")
         {
         const std::string psk_identity = reader.get_string(2, 0, 65535);

         psk = creds.psk("tls-server",
                         state.client_hello()->sni_hostname(),
                         psk_identity);

         if(psk.length() == 0)
            {
            if(policy.hide_unknown_users())
               psk = SymmetricKey(rng, 16);
            else
               throw TLS_Exception(Alert::UNKNOWN_PSK_IDENTITY,
                                   "No PSK for identifier " + psk_identity);
            }
         }

      if(kex_algo == "PSK")
         {
         std::vector<byte> zeros(psk.length());
         append_tls_length_value(m_pre_master, zeros, 2);
         append_tls_length_value(m_pre_master, psk.bits_of(), 2);
         }
#if defined(BOTAN_HAS_SRP6)
      else if(kex_algo == "SRP_SHA")
         {
         SRP6_Server_Session& srp = state.server_kex()->server_srp_params();

         m_pre_master = srp.step2(BigInt::decode(reader.get_range<byte>(2, 0, 65535))).bits_of();
         }
#endif
      else if(kex_algo == "DH" || kex_algo == "DHE_PSK" ||
              kex_algo == "ECDH" || kex_algo == "ECDHE_PSK")
         {
//.........这里部分代码省略.........