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/*
* TLS Handshake IO
* (C) 2012 Jack Lloyd
*
* Released under the terms of the Botan license
*/
#include <botan/internal/tls_handshake_io.h>
#include <botan/internal/tls_messages.h>
#include <botan/tls_record.h>
#include <botan/exceptn.h>
namespace Botan {
namespace TLS {
namespace {
inline size_t load_be24(const byte q[3])
{
return make_u32bit(0,
q[0],
q[1],
q[2]);
}
void store_be24(byte out[3], size_t val)
{
out[0] = get_byte<u32bit>(1, val);
out[1] = get_byte<u32bit>(2, val);
out[2] = get_byte<u32bit>(3, val);
}
}
Protocol_Version Stream_Handshake_IO::initial_record_version() const
{
return Protocol_Version::SSL_V3;
}
void Stream_Handshake_IO::add_input(const byte rec_type,
const byte record[],
size_t record_size,
u64bit /*record_number*/)
{
if(rec_type == HANDSHAKE)
{
m_queue.insert(m_queue.end(), record, record + record_size);
}
else if(rec_type == CHANGE_CIPHER_SPEC)
{
if(record_size != 1 || record[0] != 1)
throw Decoding_Error("Invalid ChangeCipherSpec");
// Pretend it's a regular handshake message of zero length
const byte ccs_hs[] = { HANDSHAKE_CCS, 0, 0, 0 };
m_queue.insert(m_queue.end(), ccs_hs, ccs_hs + sizeof(ccs_hs));
}
else
throw Decoding_Error("Unknown message type in handshake processing");
}
std::pair<Handshake_Type, std::vector<byte>>
Stream_Handshake_IO::get_next_record()
{
if(m_queue.size() >= 4)
{
const size_t length = load_be24(&m_queue[1]);
if(m_queue.size() >= length + 4)
{
Handshake_Type type = static_cast<Handshake_Type>(m_queue[0]);
std::vector<byte> contents(m_queue.begin() + 4,
m_queue.begin() + 4 + length);
m_queue.erase(m_queue.begin(), m_queue.begin() + 4 + length);
return std::make_pair(type, contents);
}
}
return std::make_pair(HANDSHAKE_NONE, std::vector<byte>());
}
std::vector<byte>
Stream_Handshake_IO::format(const std::vector<byte>& msg,
Handshake_Type type)
{
std::vector<byte> send_buf(4 + msg.size());
const size_t buf_size = msg.size();
send_buf[0] = type;
store_be24(&send_buf[1], buf_size);
copy_mem(&send_buf[4], &msg[0], msg.size());
return send_buf;
}
std::vector<byte> Stream_Handshake_IO::send(Handshake_Message& msg)
{
const std::vector<byte> buf = format(msg.serialize(), msg.type());
m_writer.send(HANDSHAKE, &buf[0], buf.size());
return buf;
}
Protocol_Version Datagram_Handshake_IO::initial_record_version() const
{
return Protocol_Version::DTLS_V10;
}
void Datagram_Handshake_IO::add_input(const byte rec_type,
const byte record[],
size_t record_size,
u64bit record_number)
{
if(rec_type == CHANGE_CIPHER_SPEC)
{
m_ccs_epochs.insert(static_cast<u16bit>(record_number >> 48));
return;
}
const size_t DTLS_HANDSHAKE_HEADER_LEN = 12;
if(record_size < DTLS_HANDSHAKE_HEADER_LEN)
return; // completely bogus? at least degenerate/weird
const byte msg_type = record[0];
const size_t msg_len = load_be24(&record[1]);
const u16bit message_seq = load_be<u16bit>(&record[4], 0);
const size_t fragment_offset = load_be24(&record[6]);
const size_t fragment_length = load_be24(&record[9]);
if(fragment_length + DTLS_HANDSHAKE_HEADER_LEN != record_size)
throw Decoding_Error("Bogus DTLS handshake, header sizes do not match");
m_messages[message_seq].add_fragment(&record[DTLS_HANDSHAKE_HEADER_LEN],
fragment_length,
fragment_offset,
msg_type,
msg_len);
}
std::pair<Handshake_Type, std::vector<byte>>
Datagram_Handshake_IO::get_next_record()
{
auto i = m_messages.find(m_in_message_seq);
if(i == m_messages.end() || !i->second.complete())
return std::make_pair(HANDSHAKE_NONE, std::vector<byte>());
auto m = i->second.message();
m_in_message_seq += 1;
return m;
//return i->second.message();
}
void Datagram_Handshake_IO::Handshake_Reassembly::add_fragment(
const byte fragment[],
size_t fragment_length,
size_t fragment_offset,
byte msg_type,
size_t msg_length)
{
if(m_msg_type == HANDSHAKE_NONE)
{
m_msg_type = msg_type;
m_msg_length = msg_length;
#warning DoS should resize as inputs are added (?)
m_buffer.resize(m_msg_length);
}
if(msg_type != m_msg_type || msg_length != m_msg_length)
throw Decoding_Error("Datagram_Handshake_IO - inconsistent values");
copy_mem(&m_buffer[fragment_offset], fragment, fragment_length);
}
bool Datagram_Handshake_IO::Handshake_Reassembly::complete() const
{
return true; // FIXME
}
std::pair<Handshake_Type, std::vector<byte>>
Datagram_Handshake_IO::Handshake_Reassembly::message() const
{
if(!complete())
throw Internal_Error("Datagram_Handshake_IO - message not complete");
auto msg = std::make_pair(static_cast<Handshake_Type>(m_msg_type), m_buffer);
return msg;
}
std::vector<byte>
Datagram_Handshake_IO::format(const std::vector<byte>& msg,
Handshake_Type type)
{
std::vector<byte> send_buf(12 + msg.size());
const size_t buf_size = msg.size();
send_buf[0] = type;
store_be24(&send_buf[1], buf_size);
store_be(static_cast<u16bit>(m_in_message_seq - 1), &send_buf[4]);
store_be24(&send_buf[6], 0); // fragment_offset
store_be24(&send_buf[9], buf_size); // fragment_length
copy_mem(&send_buf[12], &msg[0], msg.size());
return send_buf;
}
std::vector<byte>
Datagram_Handshake_IO::send(Handshake_Message& msg)
{
const std::vector<byte> buf = format(msg.serialize(), msg.type());
// FIXME: fragment to mtu size
m_writer.send(HANDSHAKE, &buf[0], buf.size());
return buf;
}
}
}
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