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/*
* TLS Client
* (C) 2004-2011 Jack Lloyd
*
* Released under the terms of the Botan license
*/
#include <botan/tls_client.h>
#include <botan/internal/tls_session_key.h>
#include <botan/internal/tls_state.h>
#include <botan/rsa.h>
#include <botan/dsa.h>
#include <botan/dh.h>
namespace Botan {
/*
* TLS Client Constructor
*/
TLS_Client::TLS_Client(std::tr1::function<void (const byte[], size_t)> output_fn,
std::tr1::function<void (const byte[], size_t, u16bit)> proc_fn,
TLS_Session_Manager& session_manager,
const TLS_Policy& policy,
RandomNumberGenerator& rng) :
TLS_Channel(output_fn, proc_fn),
policy(policy),
rng(rng),
session_manager(session_manager)
{
writer.set_version(policy.pref_version());
state = new Handshake_State;
state->set_expected_next(SERVER_HELLO);
state->client_hello = new Client_Hello(rng, writer, policy, state->hash);
}
void TLS_Client::add_client_cert(const X509_Certificate& cert,
Private_Key* cert_key)
{
certs.push_back(std::make_pair(cert, cert_key));
}
/*
* TLS Client Destructor
*/
TLS_Client::~TLS_Client()
{
for(size_t i = 0; i != certs.size(); i++)
delete certs[i].second;
}
/*
* Process a handshake message
*/
void TLS_Client::process_handshake_msg(Handshake_Type type,
const MemoryRegion<byte>& contents)
{
if(type == HELLO_REQUEST)
{
if(state == 0)
state = new Handshake_State();
else
return; // hello request in middle of handshake?
}
if(state == 0)
throw Unexpected_Message("Unexpected handshake message");
state->confirm_transition_to(type);
if(type != HANDSHAKE_CCS && type != HELLO_REQUEST && type != FINISHED)
state->hash.update(type, contents);
if(type == HELLO_REQUEST)
{
Hello_Request hello_request(contents);
state->client_hello = new Client_Hello(rng, writer, policy, state->hash);
}
else if(type == SERVER_HELLO)
{
state->server_hello = new Server_Hello(contents);
if(!state->client_hello->offered_suite(
state->server_hello->ciphersuite()
)
)
throw TLS_Exception(HANDSHAKE_FAILURE,
"TLS_Client: Server replied with bad ciphersuite");
state->version = state->server_hello->version();
if(state->version > state->client_hello->version())
throw TLS_Exception(HANDSHAKE_FAILURE,
"TLS_Client: Server replied with bad version");
if(state->version < policy.min_version())
throw TLS_Exception(PROTOCOL_VERSION,
"TLS_Client: Server is too old for specified policy");
writer.set_version(state->version);
reader.set_version(state->version);
state->suite = CipherSuite(state->server_hello->ciphersuite());
// if resuming, next is HANDSHAKE_CCS
if(state->suite.sig_type() != TLS_ALGO_SIGNER_ANON)
{
state->set_expected_next(CERTIFICATE);
}
else if(state->suite.kex_type() != TLS_ALGO_KEYEXCH_NOKEX)
{
state->set_expected_next(SERVER_KEX);
}
else
{
state->set_expected_next(CERTIFICATE_REQUEST); // optional
state->set_expected_next(SERVER_HELLO_DONE);
}
}
else if(type == CERTIFICATE)
{
if(state->suite.kex_type() != TLS_ALGO_KEYEXCH_NOKEX)
{
state->set_expected_next(SERVER_KEX);
}
else
{
state->set_expected_next(CERTIFICATE_REQUEST); // optional
state->set_expected_next(SERVER_HELLO_DONE);
}
state->server_certs = new Certificate(contents);
peer_certs = state->server_certs->cert_chain();
if(peer_certs.size() == 0)
throw TLS_Exception(HANDSHAKE_FAILURE,
"TLS_Client: No certificates sent by server");
if(!policy.check_cert(peer_certs))
throw TLS_Exception(BAD_CERTIFICATE,
"TLS_Client: Server certificate is not valid");
state->kex_pub = peer_certs[0].subject_public_key();
bool is_dsa = false, is_rsa = false;
if(dynamic_cast<DSA_PublicKey*>(state->kex_pub))
is_dsa = true;
else if(dynamic_cast<RSA_PublicKey*>(state->kex_pub))
is_rsa = true;
else
throw TLS_Exception(UNSUPPORTED_CERTIFICATE,
"Unknown key type received in server kex");
if((is_dsa && state->suite.sig_type() != TLS_ALGO_SIGNER_DSA) ||
(is_rsa && state->suite.sig_type() != TLS_ALGO_SIGNER_RSA))
throw TLS_Exception(ILLEGAL_PARAMETER,
"Certificate key type did not match ciphersuite");
}
else if(type == SERVER_KEX)
{
state->set_expected_next(CERTIFICATE_REQUEST); // optional
state->set_expected_next(SERVER_HELLO_DONE);
state->server_kex = new Server_Key_Exchange(contents);
if(state->kex_pub)
delete state->kex_pub;
state->kex_pub = state->server_kex->key();
bool is_dh = false, is_rsa = false;
if(dynamic_cast<DH_PublicKey*>(state->kex_pub))
is_dh = true;
else if(dynamic_cast<RSA_PublicKey*>(state->kex_pub))
is_rsa = true;
else
throw TLS_Exception(HANDSHAKE_FAILURE,
"Unknown key type received in server kex");
if((is_dh && state->suite.kex_type() != TLS_ALGO_KEYEXCH_DH) ||
(is_rsa && state->suite.kex_type() != TLS_ALGO_KEYEXCH_RSA))
throw TLS_Exception(ILLEGAL_PARAMETER,
"Certificate key type did not match ciphersuite");
if(state->suite.sig_type() != TLS_ALGO_SIGNER_ANON)
{
if(!state->server_kex->verify(peer_certs[0],
state->client_hello->random(),
state->server_hello->random()))
throw TLS_Exception(DECRYPT_ERROR,
"Bad signature on server key exchange");
}
}
else if(type == CERTIFICATE_REQUEST)
{
state->set_expected_next(SERVER_HELLO_DONE);
state->cert_req = new Certificate_Req(contents);
}
else if(type == SERVER_HELLO_DONE)
{
state->set_expected_next(HANDSHAKE_CCS);
state->server_hello_done = new Server_Hello_Done(contents);
if(state->received_handshake_msg(CERTIFICATE_REQUEST))
{
std::vector<X509_Certificate> send_certs;
std::vector<Certificate_Type> types =
state->cert_req->acceptable_types();
// FIXME: Fill in useful certs here, if any
state->client_certs = new Certificate(writer, send_certs,
state->hash);
}
state->client_kex =
new Client_Key_Exchange(rng, writer, state->hash,
state->kex_pub, state->version,
state->client_hello->version());
if(state->received_handshake_msg(CERTIFICATE_REQUEST))
{
Private_Key* key_matching_cert = 0; // FIXME
state->client_verify = new Certificate_Verify(rng,
writer, state->hash,
key_matching_cert);
}
state->keys = SessionKeys(state->suite, state->version,
state->client_kex->pre_master_secret(),
state->client_hello->random(),
state->server_hello->random());
writer.send(CHANGE_CIPHER_SPEC, 1);
writer.set_keys(state->suite, state->keys, CLIENT);
state->client_finished = new Finished(writer, state->version, CLIENT,
state->keys.master_secret(),
state->hash);
}
else if(type == HANDSHAKE_CCS)
{
state->set_expected_next(FINISHED);
reader.set_keys(state->suite, state->keys, CLIENT);
}
else if(type == FINISHED)
{
state->set_expected_next(HELLO_REQUEST);
state->server_finished = new Finished(contents);
if(!state->server_finished->verify(state->keys.master_secret(),
state->version, state->hash, SERVER))
throw TLS_Exception(DECRYPT_ERROR,
"Finished message didn't verify");
delete state;
state = 0;
active = true;
}
else
throw Unexpected_Message("Unknown handshake message received");
}
}
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