1 files changed, 129 insertions, 0 deletions
diff --git a/src/pk/dlies/dlies.cpp b/src/pk/dlies/dlies.cpp
new file mode 100644
index 000000000..2a2f33925
--- /dev/null
+++ b/src/pk/dlies/dlies.cpp
@@ -0,0 +1,129 @@
+/*************************************************
+* DLIES Source File                              *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#include <botan/dlies.h>
+#include <botan/lookup.h>
+#include <botan/look_pk.h>
+#include <botan/xor_buf.h>
+#include <memory>
+
+namespace Botan {
+
+/*************************************************
+* DLIES_Encryptor Constructor                    *
+*************************************************/
+DLIES_Encryptor::DLIES_Encryptor(const PK_Key_Agreement_Key& k,
+                                 const std::string& kdf,
+                                 const std::string& mac, u32bit mk_len) :
+   key(k), kdf_algo(kdf), mac_algo(mac), MAC_KEYLEN(mk_len)
+   {
+   }
+
+/*************************************************
+* DLIES Encryption                               *
+*************************************************/
+SecureVector<byte> DLIES_Encryptor::enc(const byte in[], u32bit length,
+                                        RandomNumberGenerator&) const
+   {
+   if(length > maximum_input_size())
+      throw Invalid_Argument("DLIES: Plaintext too large");
+   if(other_key.is_empty())
+      throw Invalid_State("DLIES: The other key was never set");
+
+   std::auto_ptr<KDF> kdf(get_kdf(kdf_algo));
+   std::auto_ptr<MessageAuthenticationCode> mac(get_mac(mac_algo));
+
+   MemoryVector<byte> v = key.public_value();
+
+   SecureVector<byte> out(v.size() + length + mac->OUTPUT_LENGTH);
+   out.copy(v, v.size());
+   out.copy(v.size(), in, length);
+
+   SecureVector<byte> vz(v, key.derive_key(other_key, other_key.size()));
+
+   const u32bit K_LENGTH = length + MAC_KEYLEN;
+   OctetString K = kdf->derive_key(K_LENGTH, vz, vz.size());
+   if(K.length() != K_LENGTH)
+      throw Encoding_Error("DLIES: KDF did not provide sufficient output");
+   byte* C = out + v.size();
+
+   xor_buf(C, K.begin() + MAC_KEYLEN, length);
+   mac->set_key(K.begin(), MAC_KEYLEN);
+
+   mac->update(C, length);
+   for(u32bit j = 0; j != 8; ++j)
+      mac->update(0);
+
+   mac->final(C + length);
+
+   return out;
+   }
+
+/*************************************************
+* Set the other parties public key               *
+*************************************************/
+void DLIES_Encryptor::set_other_key(const MemoryRegion<byte>& ok)
+   {
+   other_key = ok;
+   }
+
+/*************************************************
+* Return the max size, in bytes, of a message    *
+*************************************************/
+u32bit DLIES_Encryptor::maximum_input_size() const
+   {
+   return 32;
+   }
+
+/*************************************************
+* DLIES_Decryptor Constructor                    *
+*************************************************/
+DLIES_Decryptor::DLIES_Decryptor(const PK_Key_Agreement_Key& k,
+                                 const std::string& kdf,
+                                 const std::string& mac, u32bit mk_len) :
+   key(k), kdf_algo(kdf), mac_algo(mac),
+   MAC_KEYLEN(mk_len), PUBLIC_LEN(key.public_value().size())
+   {
+   }
+
+/*************************************************
+* DLIES Decryption                               *
+*************************************************/
+SecureVector<byte> DLIES_Decryptor::dec(const byte msg[], u32bit length) const
+   {
+   std::auto_ptr<MessageAuthenticationCode> mac(get_mac(mac_algo));
+
+   if(length < PUBLIC_LEN + mac->OUTPUT_LENGTH)
+      throw Decoding_Error("DLIES decryption: ciphertext is too short");
+
+   std::auto_ptr<KDF> kdf(get_kdf(kdf_algo));
+
+   const u32bit CIPHER_LEN = length - PUBLIC_LEN - mac->OUTPUT_LENGTH;
+
+   SecureVector<byte> v(msg, PUBLIC_LEN);
+   SecureVector<byte> C(msg + PUBLIC_LEN, CIPHER_LEN);
+   SecureVector<byte> T(msg + PUBLIC_LEN + CIPHER_LEN, mac->OUTPUT_LENGTH);
+
+   SecureVector<byte> vz(v, key.derive_key(v, v.size()));
+
+   const u32bit K_LENGTH = C.size() + MAC_KEYLEN;
+   OctetString K = kdf->derive_key(K_LENGTH, vz, vz.size());
+   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(u32bit j = 0; j != 8; ++j)
+      mac->update(0);
+   SecureVector<byte> T2 = mac->final();
+   if(T != T2)
+      throw Integrity_Failure("DLIES: message authentication failed");
+
+   xor_buf(C, K.begin() + MAC_KEYLEN, C.size());
+
+   return C;
+   }
+
+}