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/*
* TLS Channels
* (C) 2011 Jack Lloyd
*
* Released under the terms of the Botan license
*/
#include <botan/tls_channel.h>
#include <botan/internal/tls_alerts.h>
#include <botan/internal/tls_state.h>
#include <botan/loadstor.h>
namespace Botan {
TLS_Channel::TLS_Channel(std::tr1::function<void (const byte[], size_t)> socket_output_fn,
std::tr1::function<void (const byte[], size_t, u16bit)> proc_fn) :
proc_fn(proc_fn),
writer(socket_output_fn),
state(0),
active(false),
secure_renegotiation(false)
{
}
TLS_Channel::~TLS_Channel()
{
close();
delete state;
state = 0;
}
size_t TLS_Channel::received_data(const byte buf[], size_t buf_size)
{
try
{
reader.add_input(buf, buf_size);
byte rec_type = CONNECTION_CLOSED;
SecureVector<byte> record;
while(!reader.currently_empty())
{
const size_t bytes_needed = reader.get_record(rec_type, record);
if(bytes_needed > 0)
return bytes_needed;
if(rec_type == APPLICATION_DATA)
{
if(active)
{
/*
* OpenSSL among others sends empty records in versions
* before TLS v1.1 in order to randomize the IV of the
* following record. Avoid spurious callbacks.
*/
if(record.size() > 0)
proc_fn(&record[0], record.size(), NULL_ALERT);
}
else
{
throw Unexpected_Message("Application data before handshake done");
}
}
else if(rec_type == HANDSHAKE || rec_type == CHANGE_CIPHER_SPEC)
{
read_handshake(rec_type, record);
}
else if(rec_type == ALERT)
{
Alert alert_msg(record);
proc_fn(0, 0, alert_msg.type());
if(alert_msg.is_fatal() || alert_msg.type() == CLOSE_NOTIFY)
{
if(alert_msg.type() == CLOSE_NOTIFY)
alert(FATAL, CLOSE_NOTIFY);
else
alert(FATAL, NULL_ALERT);
}
}
else
throw Unexpected_Message("Unknown message type received");
}
return 0; // on a record boundary
}
catch(TLS_Exception& e)
{
alert(FATAL, e.type());
throw;
}
catch(Decoding_Error& e)
{
alert(FATAL, DECODE_ERROR);
throw;
}
catch(std::exception& e)
{
alert(FATAL, INTERNAL_ERROR);
throw;
}
}
/*
* Split up and process handshake messages
*/
void TLS_Channel::read_handshake(byte rec_type,
const MemoryRegion<byte>& rec_buf)
{
if(rec_type == HANDSHAKE)
state->queue.write(&rec_buf[0], rec_buf.size());
while(true)
{
Handshake_Type type = HANDSHAKE_NONE;
SecureVector<byte> contents;
if(rec_type == HANDSHAKE)
{
if(state->queue.size() >= 4)
{
byte head[4] = { 0 };
state->queue.peek(head, 4);
const size_t length = make_u32bit(0, head[1], head[2], head[3]);
if(state->queue.size() >= length + 4)
{
type = static_cast<Handshake_Type>(head[0]);
contents.resize(length);
state->queue.read(head, 4);
state->queue.read(&contents[0], contents.size());
}
}
}
else if(rec_type == CHANGE_CIPHER_SPEC)
{
if(state->queue.size() == 0 && rec_buf.size() == 1 && rec_buf[0] == 1)
type = HANDSHAKE_CCS;
else
throw Decoding_Error("Malformed ChangeCipherSpec message");
}
else
throw Decoding_Error("Unknown message type in handshake processing");
if(type == HANDSHAKE_NONE)
break;
process_handshake_msg(type, contents);
if(type == HANDSHAKE_CCS || !state)
break;
}
}
void TLS_Channel::queue_for_sending(const byte buf[], size_t buf_size)
{
if(active)
{
while(!pre_handshake_write_queue.end_of_data())
{
SecureVector<byte> q_buf(1024);
const size_t got = pre_handshake_write_queue.read(&q_buf[0], q_buf.size());
writer.send(APPLICATION_DATA, &q_buf[0], got);
}
writer.send(APPLICATION_DATA, buf, buf_size);
}
else
pre_handshake_write_queue.write(buf, buf_size);
}
void TLS_Channel::alert(Alert_Level alert_level, Alert_Type alert_code)
{
if(alert_code != NULL_ALERT)
{
try
{
writer.alert(alert_level, alert_code);
}
catch(...) { /* swallow it */ }
}
if(active && alert_level == FATAL)
{
reader.reset();
writer.reset();
delete state;
state = 0;
active = false;
}
}
}
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