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;/*
* TLS Server Hello and Server Hello Done
* (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_extensions.h>
#include <botan/tls_record.h>
#include <botan/internal/stl_util.h>
namespace Botan {
namespace TLS {
/*
* Create a new Server Hello message
*/
Server_Hello::Server_Hello(Record_Writer& writer,
Handshake_Hash& hash,
Protocol_Version version,
const Client_Hello& c_hello,
const std::vector<std::string>& available_cert_types,
const Policy& policy,
bool client_has_secure_renegotiation,
const MemoryRegion<byte>& reneg_info,
bool client_has_npn,
const std::vector<std::string>& next_protocols,
RandomNumberGenerator& rng) :
s_version(version),
m_session_id(rng.random_vec(32)),
s_random(make_hello_random(rng)),
m_fragment_size(c_hello.fragment_size()),
m_secure_renegotiation(client_has_secure_renegotiation),
m_renegotiation_info(reneg_info),
m_next_protocol(client_has_npn),
m_next_protocols(next_protocols)
{
suite = policy.choose_suite(
c_hello.ciphersuites(),
available_cert_types,
policy.choose_curve(c_hello.supported_ecc_curves()) != "",
false);
if(suite == 0)
throw TLS_Exception(Alert::HANDSHAKE_FAILURE,
"Can't agree on a ciphersuite with client");
comp_method = policy.choose_compression(c_hello.compression_methods());
hash.update(writer.send(*this));
}
/*
* Create a new Server Hello message
*/
Server_Hello::Server_Hello(Record_Writer& writer,
Handshake_Hash& hash,
const MemoryRegion<byte>& session_id,
Protocol_Version ver,
u16bit ciphersuite,
byte compression,
size_t max_fragment_size,
bool client_has_secure_renegotiation,
const MemoryRegion<byte>& reneg_info,
bool client_has_npn,
const std::vector<std::string>& next_protocols,
RandomNumberGenerator& rng) :
s_version(ver),
m_session_id(session_id),
s_random(make_hello_random(rng)),
suite(ciphersuite),
comp_method(compression),
m_fragment_size(max_fragment_size),
m_secure_renegotiation(client_has_secure_renegotiation),
m_renegotiation_info(reneg_info),
m_next_protocol(client_has_npn),
m_next_protocols(next_protocols)
{
hash.update(writer.send(*this));
}
/*
* Deserialize a Server Hello message
*/
Server_Hello::Server_Hello(const MemoryRegion<byte>& buf)
{
m_secure_renegotiation = false;
m_supports_session_ticket = false;
m_next_protocol = false;
if(buf.size() < 38)
throw Decoding_Error("Server_Hello: Packet corrupted");
TLS_Data_Reader reader(buf);
const byte major_version = reader.get_byte();
const byte minor_version = reader.get_byte();
s_version = Protocol_Version(major_version, minor_version);
if(s_version != Protocol_Version::SSL_V3 &&
s_version != Protocol_Version::TLS_V10 &&
s_version != Protocol_Version::TLS_V11 &&
s_version != Protocol_Version::TLS_V12)
{
throw TLS_Exception(Alert::PROTOCOL_VERSION,
"Server_Hello: Unsupported server version");
}
s_random = reader.get_fixed<byte>(32);
m_session_id = reader.get_range<byte>(1, 0, 32);
suite = reader.get_u16bit();
comp_method = reader.get_byte();
Extensions extensions(reader);
if(Renegotation_Extension* reneg = extensions.get<Renegotation_Extension>())
{
// checked by Client / Server as they know the handshake state
m_secure_renegotiation = true;
m_renegotiation_info = reneg->renegotiation_info();
}
if(Next_Protocol_Notification* npn = extensions.get<Next_Protocol_Notification>())
{
m_next_protocols = npn->protocols();
m_next_protocol = true;
}
if(Session_Ticket* ticket = extensions.get<Session_Ticket>())
{
if(!ticket->contents().empty())
throw Decoding_Error("TLS server sent non-empty session ticket extension");
m_supports_session_ticket = true;
}
}
/*
* Serialize a Server Hello message
*/
MemoryVector<byte> Server_Hello::serialize() const
{
MemoryVector<byte> buf;
buf.push_back(s_version.major_version());
buf.push_back(s_version.minor_version());
buf += s_random;
append_tls_length_value(buf, m_session_id, 1);
buf.push_back(get_byte(0, suite));
buf.push_back(get_byte(1, suite));
buf.push_back(comp_method);
Extensions extensions;
if(m_secure_renegotiation)
extensions.add(new Renegotation_Extension(m_renegotiation_info));
if(m_fragment_size != 0)
extensions.add(new Maximum_Fragment_Length(m_fragment_size));
if(m_next_protocol)
extensions.add(new Next_Protocol_Notification(m_next_protocols));
buf += extensions.serialize();
return buf;
}
/*
* Create a new Server Hello Done message
*/
Server_Hello_Done::Server_Hello_Done(Record_Writer& writer,
Handshake_Hash& hash)
{
hash.update(writer.send(*this));
}
/*
* Deserialize a Server Hello Done message
*/
Server_Hello_Done::Server_Hello_Done(const MemoryRegion<byte>& buf)
{
if(buf.size())
throw Decoding_Error("Server_Hello_Done: Must be empty, and is not");
}
/*
* Serialize a Server Hello Done message
*/
MemoryVector<byte> Server_Hello_Done::serialize() const
{
return MemoryVector<byte>();
}
}
}
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