1 files changed, 146 insertions, 0 deletions
diff --git a/src/lib/pubkey/dlies/dlies.cpp b/src/lib/pubkey/dlies/dlies.cpp
new file mode 100644
index 000000000..715b55a36
--- /dev/null
+++ b/src/lib/pubkey/dlies/dlies.cpp
@@ -0,0 +1,146 @@
+/*
+* DLIES
+* (C) 1999-2007 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/dlies.h>
+#include <botan/internal/xor_buf.h>
+
+namespace Botan {
+
+/*
+* DLIES_Encryptor Constructor
+*/
+DLIES_Encryptor::DLIES_Encryptor(const PK_Key_Agreement_Key& key,
+                                 KDF* kdf_obj,
+                                 MessageAuthenticationCode* mac_obj,
+                                 size_t mac_kl) :
+   ka(key, "Raw"),
+   kdf(kdf_obj),
+   mac(mac_obj),
+   mac_keylen(mac_kl)
+   {
+   my_key = key.public_value();
+   }
+
+DLIES_Encryptor::~DLIES_Encryptor()
+   {
+   delete kdf;
+   delete mac;
+   }
+
+/*
+* DLIES Encryption
+*/
+std::vector<byte> DLIES_Encryptor::enc(const byte in[], size_t length,
+                                       RandomNumberGenerator&) const
+   {
+   if(length > maximum_input_size())
+      throw Invalid_Argument("DLIES: Plaintext too large");
+   if(other_key.empty())
+      throw Invalid_State("DLIES: The other key was never set");
+
+   secure_vector<byte> out(my_key.size() + length + mac->output_length());
+   buffer_insert(out, 0, my_key);
+   buffer_insert(out, my_key.size(), in, length);
+
+   secure_vector<byte> vz(my_key.begin(), my_key.end());
+   vz += ka.derive_key(0, other_key).bits_of();
+
+   const size_t K_LENGTH = length + mac_keylen;
+   OctetString K = kdf->derive_key(K_LENGTH, vz);
+
+   if(K.length() != K_LENGTH)
+      throw Encoding_Error("DLIES: KDF did not provide sufficient output");
+   byte* C = &out[my_key.size()];
+
+   xor_buf(C, K.begin() + mac_keylen, length);
+   mac->set_key(K.begin(), mac_keylen);
+
+   mac->update(C, length);
+   for(size_t j = 0; j != 8; ++j)
+      mac->update(0);
+
+   mac->final(C + length);
+
+   return unlock(out);
+   }
+
+/*
+* Set the other parties public key
+*/
+void DLIES_Encryptor::set_other_key(const std::vector<byte>& ok)
+   {
+   other_key = ok;
+   }
+
+/*
+* Return the max size, in bytes, of a message
+*/
+size_t DLIES_Encryptor::maximum_input_size() const
+   {
+   return 32;
+   }
+
+/*
+* DLIES_Decryptor Constructor
+*/
+DLIES_Decryptor::DLIES_Decryptor(const PK_Key_Agreement_Key& key,
+                                 KDF* kdf_obj,
+                                 MessageAuthenticationCode* mac_obj,
+                                 size_t mac_kl) :
+   ka(key, "Raw"),
+   kdf(kdf_obj),
+   mac(mac_obj),
+   mac_keylen(mac_kl)
+   {
+   my_key = key.public_value();
+   }
+
+DLIES_Decryptor::~DLIES_Decryptor()
+   {
+   delete kdf;
+   delete mac;
+   }
+
+/*
+* DLIES Decryption
+*/
+secure_vector<byte> DLIES_Decryptor::dec(const byte msg[], size_t length) const
+   {
+   if(length < my_key.size() + mac->output_length())
+      throw Decoding_Error("DLIES decryption: ciphertext is too short");
+
+   const size_t CIPHER_LEN = length - my_key.size() - mac->output_length();
+
+   std::vector<byte> v(msg, msg + my_key.size());
+
+   secure_vector<byte> C(msg + my_key.size(), msg + my_key.size() + CIPHER_LEN);
+
+   secure_vector<byte> T(msg + my_key.size() + CIPHER_LEN,
+                         msg + my_key.size() + CIPHER_LEN + mac->output_length());
+
+   secure_vector<byte> vz(msg, msg + my_key.size());
+   vz += ka.derive_key(0, v).bits_of();
+
+   const size_t K_LENGTH = C.size() + mac_keylen;
+   OctetString K = kdf->derive_key(K_LENGTH, vz);
+   if(K.length() != K_LENGTH)
+      throw Encoding_Error("DLIES: KDF did not provide sufficient output");
+
+   mac->set_key(K.begin(), mac_keylen);
+   mac->update(C);
+   for(size_t j = 0; j != 8; ++j)
+      mac->update(0);
+   secure_vector<byte> T2 = mac->final();
+   if(T != T2)
+      throw Decoding_Error("DLIES: message authentication failed");
+
+   xor_buf(C, K.begin() + mac_keylen, C.size());
+
+   return C;
+   }
+
+}