Botan  1.10.9
Public Member Functions | List of all members
Botan::Client_Key_Exchange Class Reference

#include <tls_messages.h>

Inheritance diagram for Botan::Client_Key_Exchange:
Botan::HandshakeMessage

Public Member Functions

 Client_Key_Exchange (RandomNumberGenerator &rng, Record_Writer &output, HandshakeHash &hash, const Public_Key *my_key, Version_Code using_version, Version_Code pref_version)
 
 Client_Key_Exchange (const MemoryRegion< byte > &buf, const CipherSuite &suite, Version_Code using_version)
 
SecureVector< bytepre_master_secret () const
 
SecureVector< bytepre_master_secret (RandomNumberGenerator &rng, const Private_Key *key, Version_Code version)
 
void send (Record_Writer &, HandshakeHash &) const
 
Handshake_Type type () const
 

Detailed Description

Client Key Exchange Message

Definition at line 86 of file tls_messages.h.

Constructor & Destructor Documentation

Botan::Client_Key_Exchange::Client_Key_Exchange ( RandomNumberGenerator rng,
Record_Writer writer,
HandshakeHash hash,
const Public_Key pub_key,
Version_Code  using_version,
Version_Code  pref_version 
)

Create a new Client Key Exchange message

Definition at line 22 of file c_kex.cpp.

References Botan::PK_Encryptor::encrypt(), Botan::RandomNumberGenerator::random_vec(), Botan::HandshakeMessage::send(), and Botan::SSL_V3.

28  {
29  include_length = true;
30 
31  if(const DH_PublicKey* dh_pub = dynamic_cast<const DH_PublicKey*>(pub_key))
32  {
33  DH_PrivateKey priv_key(rng, dh_pub->get_domain());
34 
35  PK_Key_Agreement ka(priv_key, "Raw");
36 
37  pre_master = ka.derive_key(0, dh_pub->public_value()).bits_of();
38 
39  key_material = priv_key.public_value();
40  }
41  else if(const RSA_PublicKey* rsa_pub = dynamic_cast<const RSA_PublicKey*>(pub_key))
42  {
43  pre_master = rng.random_vec(48);
44  pre_master[0] = (pref_version >> 8) & 0xFF;
45  pre_master[1] = (pref_version ) & 0xFF;
46 
47  PK_Encryptor_EME encryptor(*rsa_pub, "PKCS1v15");
48 
49  key_material = encryptor.encrypt(pre_master, rng);
50 
51  if(using_version == SSL_V3)
52  include_length = false;
53  }
54  else
55  throw Invalid_Argument("Client_Key_Exchange: Key not RSA or DH");
56 
57  send(writer, hash);
58  }
void send(Record_Writer &, HandshakeHash &) const
Definition: hello.cpp:16
std::invalid_argument Invalid_Argument
Definition: exceptn.h:20
RandomNumberGenerator * rng
Definition: global_rng.cpp:165
Botan::Client_Key_Exchange::Client_Key_Exchange ( const MemoryRegion< byte > &  contents,
const CipherSuite suite,
Version_Code  using_version 
)

Read a Client Key Exchange message

Definition at line 63 of file c_kex.cpp.

References Botan::CipherSuite::kex_type(), Botan::SSL_V3, and Botan::TLS_ALGO_KEYEXCH_RSA.

66  {
67  include_length = true;
68 
69  if(using_version == SSL_V3 && (suite.kex_type() == TLS_ALGO_KEYEXCH_RSA))
70  include_length = false;
71 
72  deserialize(contents);
73  }

Member Function Documentation

SecureVector< byte > Botan::Client_Key_Exchange::pre_master_secret ( ) const

Return the pre_master_secret

Definition at line 160 of file c_kex.cpp.

161  {
162  return pre_master;
163  }
SecureVector< byte > Botan::Client_Key_Exchange::pre_master_secret ( RandomNumberGenerator rng,
const Private_Key priv_key,
Version_Code  version 
)

Return the pre_master_secret

Definition at line 108 of file c_kex.cpp.

References Botan::OctetString::bits_of(), Botan::PK_Decryptor::decrypt(), Botan::PK_Key_Agreement::derive_key(), Botan::make_u16bit(), Botan::RandomNumberGenerator::random_vec(), and Botan::MemoryRegion< T >::size().

111  {
112 
113  if(const DH_PrivateKey* dh_priv = dynamic_cast<const DH_PrivateKey*>(priv_key))
114  {
115  try {
116  PK_Key_Agreement ka(*dh_priv, "Raw");
117 
118  pre_master = ka.derive_key(0, key_material).bits_of();
119  }
120  catch(...)
121  {
122  /*
123  * Something failed in the DH computation. To avoid possible
124  * timing attacks, randomize the pre-master output and carry
125  * on, allowing the protocol to fail later in the finished
126  * checks.
127  */
128  pre_master = rng.random_vec(dh_priv->public_value().size());
129  }
130 
131  return pre_master;
132  }
133  else if(const RSA_PrivateKey* rsa_priv = dynamic_cast<const RSA_PrivateKey*>(priv_key))
134  {
135  PK_Decryptor_EME decryptor(*rsa_priv, "PKCS1v15");
136 
137  try {
138  pre_master = decryptor.decrypt(key_material);
139 
140  if(pre_master.size() != 48 ||
141  make_u16bit(pre_master[0], pre_master[1]) != version)
142  throw Decoding_Error("Client_Key_Exchange: Secret corrupted");
143  }
144  catch(...)
145  {
146  pre_master = rng.random_vec(48);
147  pre_master[0] = (version >> 8) & 0xFF;
148  pre_master[1] = (version ) & 0xFF;
149  }
150 
151  return pre_master;
152  }
153  else
154  throw Invalid_Argument("Client_Key_Exchange: Bad key for decrypt");
155  }
std::invalid_argument Invalid_Argument
Definition: exceptn.h:20
RandomNumberGenerator * rng
Definition: global_rng.cpp:165
size_t size() const
Definition: secmem.h:29
u16bit make_u16bit(byte i0, byte i1)
Definition: loadstor.h:47
void Botan::HandshakeMessage::send ( Record_Writer writer,
HandshakeHash hash 
) const
inherited

Definition at line 16 of file hello.cpp.

References Botan::Record_Writer::flush(), Botan::HANDSHAKE, Botan::Record_Writer::send(), Botan::MemoryRegion< T >::size(), Botan::HandshakeMessage::type(), and Botan::HandshakeHash::update().

Referenced by Botan::Certificate::Certificate(), Botan::Certificate_Req::Certificate_Req(), Botan::Certificate_Verify::Certificate_Verify(), Botan::Client_Hello::Client_Hello(), Client_Key_Exchange(), Botan::Finished::Finished(), Botan::Hello_Request::Hello_Request(), Botan::Server_Hello::Server_Hello(), Botan::Server_Hello_Done::Server_Hello_Done(), and Botan::Server_Key_Exchange::Server_Key_Exchange().

17  {
18  SecureVector<byte> buf = serialize();
19  SecureVector<byte> send_buf(4);
20 
21  const size_t buf_size = buf.size();
22 
23  send_buf[0] = type();
24 
25  for(size_t i = 1; i != 4; ++i)
26  send_buf[i] = get_byte<u32bit>(i, buf_size);
27 
28  send_buf += buf;
29 
30  hash.update(send_buf);
31 
32  writer.send(HANDSHAKE, &send_buf[0], send_buf.size());
33  writer.flush();
34  }
virtual Handshake_Type type() const =0
Handshake_Type Botan::Client_Key_Exchange::type ( ) const
inlinevirtual

Implements Botan::HandshakeMessage.

Definition at line 89 of file tls_messages.h.

References Botan::CLIENT_KEX.

89 { return CLIENT_KEX; }

The documentation for this class was generated from the following files: