diff options
Diffstat (limited to 'src/tls/tls_channel.cpp')
| -rw-r--r-- | src/tls/tls_channel.cpp | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/src/tls/tls_channel.cpp b/src/tls/tls_channel.cpp new file mode 100644 index 000000000..d737ef237 --- /dev/null +++ b/src/tls/tls_channel.cpp @@ -0,0 +1,300 @@ +/* +* TLS Channels +* (C) 2011-2012 Jack Lloyd +* +* Released under the terms of the Botan license +*/ + +#include <botan/tls_channel.h> +#include <botan/internal/tls_handshake_state.h> +#include <botan/internal/tls_messages.h> +#include <botan/internal/assert.h> +#include <botan/loadstor.h> + +namespace Botan { + +namespace TLS { + +Channel::Channel(std::tr1::function<void (const byte[], size_t)> socket_output_fn, + std::tr1::function<void (const byte[], size_t, Alert)> proc_fn, + std::tr1::function<bool (const Session&)> handshake_complete) : + proc_fn(proc_fn), + handshake_fn(handshake_complete), + writer(socket_output_fn), + state(0), + handshake_completed(false), + connection_closed(false) + { + } + +Channel::~Channel() + { + delete state; + state = 0; + } + +size_t Channel::received_data(const byte buf[], size_t buf_size) + { + try + { + while(buf_size) + { + byte rec_type = CONNECTION_CLOSED; + MemoryVector<byte> record; + size_t consumed = 0; + + const size_t needed = reader.add_input(buf, buf_size, + consumed, + rec_type, record); + + buf += consumed; + buf_size -= consumed; + + BOTAN_ASSERT(buf_size == 0 || needed == 0, + "Got a full record or consumed all input"); + + if(buf_size == 0 && needed != 0) + return needed; // need more data to complete record + + if(rec_type == APPLICATION_DATA) + { + if(handshake_completed) + { + /* + * 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(), 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); + + alert_notify(alert_msg); + + proc_fn(0, 0, alert_msg); + + if(alert_msg.type() == Alert::CLOSE_NOTIFY) + { + if(connection_closed) + reader.reset(); + else + send_alert(Alert(Alert::CLOSE_NOTIFY)); // reply in kind + } + else if(alert_msg.is_fatal()) + { + // delete state immediately + connection_closed = true; + + delete state; + state = 0; + + writer.reset(); + reader.reset(); + } + } + else + throw Unexpected_Message("Unknown TLS message type " + + to_string(rec_type) + " received"); + } + + return 0; // on a record boundary + } + catch(TLS_Exception& e) + { + send_alert(Alert(e.type(), true)); + throw; + } + catch(Decoding_Error& e) + { + send_alert(Alert(Alert::DECODE_ERROR, true)); + throw; + } + catch(Internal_Error& e) + { + send_alert(Alert(Alert::INTERNAL_ERROR, true)); + throw; + } + catch(std::exception& e) + { + send_alert(Alert(Alert::INTERNAL_ERROR, true)); + throw; + } + } + +/* +* Split up and process handshake messages +*/ +void Channel::read_handshake(byte rec_type, + const MemoryRegion<byte>& rec_buf) + { + if(rec_type == HANDSHAKE) + { + if(!state) + state = new Handshake_State; + state->queue.write(&rec_buf[0], rec_buf.size()); + } + + while(true) + { + Handshake_Type type = HANDSHAKE_NONE; + MemoryVector<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 Channel::send(const byte buf[], size_t buf_size) + { + if(!is_active()) + throw std::runtime_error("Data cannot be sent on inactive TLS connection"); + + writer.send(APPLICATION_DATA, buf, buf_size); + } + +void Channel::send_alert(const Alert& alert) + { + if(alert.is_valid() && !connection_closed) + { + try + { + writer.send_alert(alert); + } + catch(...) { /* swallow it */ } + } + + if(!connection_closed && (alert.type() == Alert::CLOSE_NOTIFY || alert.is_fatal())) + { + connection_closed = true; + + delete state; + state = 0; + + writer.reset(); + } + } + +void Channel::Secure_Renegotiation_State::update(Client_Hello* client_hello) + { + if(initial_handshake) + { + secure_renegotiation = client_hello->secure_renegotiation(); + } + else + { + if(secure_renegotiation != client_hello->secure_renegotiation()) + throw TLS_Exception(Alert::HANDSHAKE_FAILURE, + "Client changed its mind about secure renegotiation"); + } + + if(client_hello->secure_renegotiation()) + { + const MemoryVector<byte>& data = client_hello->renegotiation_info(); + + if(initial_handshake) + { + if(!data.empty()) + throw TLS_Exception(Alert::HANDSHAKE_FAILURE, + "Client sent renegotiation data on initial handshake"); + } + else + { + if(data != for_client_hello()) + throw TLS_Exception(Alert::HANDSHAKE_FAILURE, + "Client sent bad renegotiation data"); + } + } + } + +void Channel::Secure_Renegotiation_State::update(Server_Hello* server_hello) + { + if(initial_handshake) + { + /* If the client offered but server rejected, then this toggles + * secure_renegotiation to off + */ + secure_renegotiation = server_hello->secure_renegotiation(); + } + else + { + if(secure_renegotiation != server_hello->secure_renegotiation()) + throw TLS_Exception(Alert::HANDSHAKE_FAILURE, + "Server changed its mind about secure renegotiation"); + } + + if(secure_renegotiation) + { + const MemoryVector<byte>& data = server_hello->renegotiation_info(); + + if(initial_handshake) + { + if(!data.empty()) + throw TLS_Exception(Alert::HANDSHAKE_FAILURE, + "Server sent renegotiation data on initial handshake"); + } + else + { + if(data != for_server_hello()) + throw TLS_Exception(Alert::HANDSHAKE_FAILURE, + "Server sent bad renegotiation data"); + } + } + + initial_handshake = false; + } + +void Channel::Secure_Renegotiation_State::update(Finished* client_finished, + Finished* server_finished) + { + client_verify = client_finished->verify_data(); + server_verify = server_finished->verify_data(); + } + +} + +} |