1 files changed, 287 insertions, 0 deletions
diff --git a/src/lib/tls/msg_client_hello.cpp b/src/lib/tls/msg_client_hello.cpp
new file mode 100644
index 000000000..0d91af472
--- /dev/null
+++ b/src/lib/tls/msg_client_hello.cpp
@@ -0,0 +1,287 @@
+/*
+* TLS Hello Request and Client Hello Messages
+* (C) 2004-2011 Jack Lloyd
+*
+* Released under the terms of the Botan license
+*/
+
+#include <botan/internal/tls_messages.h>
+#include <botan/internal/tls_reader.h>
+#include <botan/internal/tls_session_key.h>
+#include <botan/internal/tls_handshake_io.h>
+#include <botan/internal/stl_util.h>
+#include <chrono>
+
+namespace Botan {
+
+namespace TLS {
+
+enum {
+   TLS_EMPTY_RENEGOTIATION_INFO_SCSV        = 0x00FF
+};
+
+std::vector<byte> make_hello_random(RandomNumberGenerator& rng)
+   {
+   std::vector<byte> buf(32);
+
+   const u32bit time32 = static_cast<u32bit>(
+      std::chrono::system_clock::to_time_t(std::chrono::system_clock::now()));
+
+   store_be(time32, &buf[0]);
+   rng.randomize(&buf[4], buf.size() - 4);
+   return buf;
+   }
+
+/*
+* Create a new Hello Request message
+*/
+Hello_Request::Hello_Request(Handshake_IO& io)
+   {
+   io.send(*this);
+   }
+
+/*
+* Deserialize a Hello Request message
+*/
+Hello_Request::Hello_Request(const std::vector<byte>& buf)
+   {
+   if(buf.size())
+      throw Decoding_Error("Bad Hello_Request, has non-zero size");
+   }
+
+/*
+* Serialize a Hello Request message
+*/
+std::vector<byte> Hello_Request::serialize() const
+   {
+   return std::vector<byte>();
+   }
+
+/*
+* Create a new Client Hello message
+*/
+Client_Hello::Client_Hello(Handshake_IO& io,
+                           Handshake_Hash& hash,
+                           Protocol_Version version,
+                           const Policy& policy,
+                           RandomNumberGenerator& rng,
+                           const std::vector<byte>& reneg_info,
+                           bool next_protocol,
+                           const std::string& hostname,
+                           const std::string& srp_identifier) :
+   m_version(version),
+   m_random(make_hello_random(rng)),
+   m_suites(policy.ciphersuite_list(m_version, (srp_identifier != ""))),
+   m_comp_methods(policy.compression())
+   {
+   m_extensions.add(new Renegotiation_Extension(reneg_info));
+   m_extensions.add(new SRP_Identifier(srp_identifier));
+   m_extensions.add(new Server_Name_Indicator(hostname));
+   m_extensions.add(new Session_Ticket());
+   m_extensions.add(new Supported_Elliptic_Curves(policy.allowed_ecc_curves()));
+
+   if(policy.negotiate_heartbeat_support())
+      m_extensions.add(new Heartbeat_Support_Indicator(true));
+
+   if(m_version.supports_negotiable_signature_algorithms())
+      m_extensions.add(new Signature_Algorithms(policy.allowed_signature_hashes(),
+                                                policy.allowed_signature_methods()));
+
+   if(reneg_info.empty() && next_protocol)
+      m_extensions.add(new Next_Protocol_Notification());
+
+   hash.update(io.send(*this));
+   }
+
+/*
+* Create a new Client Hello message (session resumption case)
+*/
+Client_Hello::Client_Hello(Handshake_IO& io,
+                           Handshake_Hash& hash,
+                           const Policy& policy,
+                           RandomNumberGenerator& rng,
+                           const std::vector<byte>& reneg_info,
+                           const Session& session,
+                           bool next_protocol) :
+   m_version(session.version()),
+   m_session_id(session.session_id()),
+   m_random(make_hello_random(rng)),
+   m_suites(policy.ciphersuite_list(m_version, (session.srp_identifier() != ""))),
+   m_comp_methods(policy.compression())
+   {
+   if(!value_exists(m_suites, session.ciphersuite_code()))
+      m_suites.push_back(session.ciphersuite_code());
+
+   if(!value_exists(m_comp_methods, session.compression_method()))
+      m_comp_methods.push_back(session.compression_method());
+
+   m_extensions.add(new Renegotiation_Extension(reneg_info));
+   m_extensions.add(new SRP_Identifier(session.srp_identifier()));
+   m_extensions.add(new Server_Name_Indicator(session.server_info().hostname()));
+   m_extensions.add(new Session_Ticket(session.session_ticket()));
+   m_extensions.add(new Supported_Elliptic_Curves(policy.allowed_ecc_curves()));
+
+   if(policy.negotiate_heartbeat_support())
+      m_extensions.add(new Heartbeat_Support_Indicator(true));
+
+   if(session.fragment_size() != 0)
+      m_extensions.add(new Maximum_Fragment_Length(session.fragment_size()));
+
+   if(m_version.supports_negotiable_signature_algorithms())
+      m_extensions.add(new Signature_Algorithms(policy.allowed_signature_hashes(),
+                                                policy.allowed_signature_methods()));
+
+   if(reneg_info.empty() && next_protocol)
+      m_extensions.add(new Next_Protocol_Notification());
+
+   hash.update(io.send(*this));
+   }
+
+/*
+* Read a counterparty client hello
+*/
+Client_Hello::Client_Hello(const std::vector<byte>& buf, Handshake_Type type)
+   {
+   if(type == CLIENT_HELLO)
+      deserialize(buf);
+   else
+      deserialize_sslv2(buf);
+   }
+
+void Client_Hello::update_hello_cookie(const Hello_Verify_Request& hello_verify)
+   {
+   if(!m_version.is_datagram_protocol())
+      throw std::runtime_error("Cannot use hello cookie with stream protocol");
+
+   m_hello_cookie = hello_verify.cookie();
+   }
+
+/*
+* Serialize a Client Hello message
+*/
+std::vector<byte> Client_Hello::serialize() const
+   {
+   std::vector<byte> buf;
+
+   buf.push_back(m_version.major_version());
+   buf.push_back(m_version.minor_version());
+   buf += m_random;
+
+   append_tls_length_value(buf, m_session_id, 1);
+
+   if(m_version.is_datagram_protocol())
+      append_tls_length_value(buf, m_hello_cookie, 1);
+
+   append_tls_length_value(buf, m_suites, 2);
+   append_tls_length_value(buf, m_comp_methods, 1);
+
+   /*
+   * May not want to send extensions at all in some cases. If so,
+   * should include SCSV value (if reneg info is empty, if not we are
+   * renegotiating with a modern server)
+   */
+
+   buf += m_extensions.serialize();
+
+   return buf;
+   }
+
+void Client_Hello::deserialize_sslv2(const std::vector<byte>& buf)
+   {
+   if(buf.size() < 12 || buf[0] != 1)
+      throw Decoding_Error("Client_Hello: SSLv2 hello corrupted");
+
+   const size_t cipher_spec_len = make_u16bit(buf[3], buf[4]);
+   const size_t m_session_id_len = make_u16bit(buf[5], buf[6]);
+   const size_t challenge_len = make_u16bit(buf[7], buf[8]);
+
+   const size_t expected_size =
+      (9 + m_session_id_len + cipher_spec_len + challenge_len);
+
+   if(buf.size() != expected_size)
+      throw Decoding_Error("Client_Hello: SSLv2 hello corrupted");
+
+   if(m_session_id_len != 0 || cipher_spec_len % 3 != 0 ||
+      (challenge_len < 16 || challenge_len > 32))
+      {
+      throw Decoding_Error("Client_Hello: SSLv2 hello corrupted");
+      }
+
+   m_version = Protocol_Version(buf[1], buf[2]);
+
+   for(size_t i = 9; i != 9 + cipher_spec_len; i += 3)
+      {
+      if(buf[i] != 0) // a SSLv2 cipherspec; ignore it
+         continue;
+
+      m_suites.push_back(make_u16bit(buf[i+1], buf[i+2]));
+      }
+
+   m_random.resize(challenge_len);
+   copy_mem(&m_random[0], &buf[9+cipher_spec_len+m_session_id_len], challenge_len);
+
+   if(offered_suite(static_cast<u16bit>(TLS_EMPTY_RENEGOTIATION_INFO_SCSV)))
+      m_extensions.add(new Renegotiation_Extension());
+   }
+
+/*
+* Deserialize a Client Hello message
+*/
+void Client_Hello::deserialize(const std::vector<byte>& buf)
+   {
+   if(buf.size() == 0)
+      throw Decoding_Error("Client_Hello: Packet corrupted");
+
+   if(buf.size() < 41)
+      throw Decoding_Error("Client_Hello: Packet corrupted");
+
+   TLS_Data_Reader reader(buf);
+
+   const byte major_version = reader.get_byte();
+   const byte minor_version = reader.get_byte();
+
+   m_version = Protocol_Version(major_version, minor_version);
+
+   m_random = reader.get_fixed<byte>(32);
+
+   if(m_version.is_datagram_protocol())
+      m_hello_cookie = reader.get_range<byte>(1, 0, 255);
+
+   m_session_id = reader.get_range<byte>(1, 0, 32);
+
+   m_suites = reader.get_range_vector<u16bit>(2, 1, 32767);
+
+   m_comp_methods = reader.get_range_vector<byte>(1, 1, 255);
+
+   m_extensions.deserialize(reader);
+
+   if(offered_suite(static_cast<u16bit>(TLS_EMPTY_RENEGOTIATION_INFO_SCSV)))
+      {
+      if(Renegotiation_Extension* reneg = m_extensions.get<Renegotiation_Extension>())
+         {
+         if(!reneg->renegotiation_info().empty())
+            throw TLS_Exception(Alert::HANDSHAKE_FAILURE,
+                                "Client send renegotiation SCSV and non-empty extension");
+         }
+      else
+         {
+         // add fake extension
+         m_extensions.add(new Renegotiation_Extension());
+         }
+      }
+   }
+
+/*
+* Check if we offered this ciphersuite
+*/
+bool Client_Hello::offered_suite(u16bit ciphersuite) const
+   {
+   for(size_t i = 0; i != m_suites.size(); ++i)
+      if(m_suites[i] == ciphersuite)
+         return true;
+   return false;
+   }
+
+}
+
+}