1 files changed, 86 insertions, 0 deletions
diff --git a/lib/tls/tls_session_key.cpp b/lib/tls/tls_session_key.cpp
new file mode 100644
index 000000000..06cd1d0a1
--- /dev/null
+++ b/lib/tls/tls_session_key.cpp
@@ -0,0 +1,86 @@
+/*
+* TLS Session Key
+* (C) 2004-2006,2011 Jack Lloyd
+*
+* Released under the terms of the Botan license
+*/
+
+#include <botan/internal/tls_session_key.h>
+#include <botan/internal/tls_handshake_state.h>
+#include <botan/internal/tls_messages.h>
+#include <botan/lookup.h>
+#include <memory>
+
+namespace Botan {
+
+namespace TLS {
+
+/**
+* Session_Keys Constructor
+*/
+Session_Keys::Session_Keys(const Handshake_State* state,
+                           const secure_vector<byte>& pre_master_secret,
+                           bool resuming)
+   {
+   const size_t cipher_keylen = state->ciphersuite().cipher_keylen();
+   const size_t mac_keylen = state->ciphersuite().mac_keylen();
+   const size_t cipher_ivlen = state->ciphersuite().cipher_ivlen();
+
+   const size_t prf_gen = 2 * (mac_keylen + cipher_keylen + cipher_ivlen);
+
+   const byte MASTER_SECRET_MAGIC[] = {
+      0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x20, 0x73, 0x65, 0x63, 0x72, 0x65, 0x74 };
+
+   const byte KEY_GEN_MAGIC[] = {
+      0x6B, 0x65, 0x79, 0x20, 0x65, 0x78, 0x70, 0x61, 0x6E, 0x73, 0x69, 0x6F, 0x6E };
+
+   std::unique_ptr<KDF> prf(state->protocol_specific_prf());
+
+   if(resuming)
+      {
+      master_sec = pre_master_secret;
+      }
+   else
+      {
+      secure_vector<byte> salt;
+
+      if(state->version() != Protocol_Version::SSL_V3)
+         salt += std::make_pair(MASTER_SECRET_MAGIC, sizeof(MASTER_SECRET_MAGIC));
+
+      salt += state->client_hello()->random();
+      salt += state->server_hello()->random();
+
+      master_sec = prf->derive_key(48, pre_master_secret, salt);
+      }
+
+   secure_vector<byte> salt;
+   if(state->version() != Protocol_Version::SSL_V3)
+      salt += std::make_pair(KEY_GEN_MAGIC, sizeof(KEY_GEN_MAGIC));
+   salt += state->server_hello()->random();
+   salt += state->client_hello()->random();
+
+   SymmetricKey keyblock = prf->derive_key(prf_gen, master_sec, salt);
+
+   const byte* key_data = keyblock.begin();
+
+   c_mac = SymmetricKey(key_data, mac_keylen);
+   key_data += mac_keylen;
+
+   s_mac = SymmetricKey(key_data, mac_keylen);
+   key_data += mac_keylen;
+
+   c_cipher = SymmetricKey(key_data, cipher_keylen);
+   key_data += cipher_keylen;
+
+   s_cipher = SymmetricKey(key_data, cipher_keylen);
+   key_data += cipher_keylen;
+
+   c_iv = InitializationVector(key_data, cipher_ivlen);
+   key_data += cipher_ivlen;
+
+   s_iv = InitializationVector(key_data, cipher_ivlen);
+   }
+
+}
+
+}