1 files changed, 12 insertions, 26 deletions
diff --git a/src/lib/pubkey/mce/mce_kem.cpp b/src/lib/pubkey/mce/mce_kem.cpp
index b24c42f85..dede67731 100644
--- a/src/lib/pubkey/mce/mce_kem.cpp
+++ b/src/lib/pubkey/mce/mce_kem.cpp
@@ -7,56 +7,42 @@
  */
 
 #include <botan/mce_kem.h>
+#include <botan/internal/mce_internal.h>
 #include <botan/sha2_64.h>
 
 namespace Botan {
 
 McEliece_KEM_Encryptor::McEliece_KEM_Encryptor(const McEliece_PublicKey& public_key) :
-   m_raw_pub_op(public_key, public_key.get_code_length())
+   m_key(public_key)
    {
    }
 
 std::pair<secure_vector<byte>, secure_vector<byte>>
 McEliece_KEM_Encryptor::encrypt(RandomNumberGenerator& rng)
    {
-   const McEliece_PublicKey& key = m_raw_pub_op.get_key();
-   secure_vector<Botan::byte> plaintext((key.get_message_word_bit_length()+7)/8);
-   rng.randomize(plaintext.data(), plaintext.size());
+   const secure_vector<byte> plaintext = m_key.random_plaintext_element(rng);
 
-   // unset unused bits in the last plaintext byte
-   u32bit used = key.get_message_word_bit_length() % 8;
-   if(used)
-      {
-      byte mask = (1 << used) - 1;
-      plaintext[plaintext.size() - 1] &= mask;
-      }
-
-   secure_vector<gf2m> err_pos = create_random_error_positions(key.get_code_length(), key.get_t(), rng);
-
-   mceliece_message_parts parts(err_pos, plaintext, key.get_code_length());
-   secure_vector<Botan::byte> message_and_error_input = parts.get_concat();
+   secure_vector<byte> ciphertext, error_mask;
+   mceliece_encrypt(ciphertext, error_mask, plaintext, m_key, rng);
 
    SHA_512 hash;
-   hash.update(message_and_error_input);
+   hash.update(plaintext);
+   hash.update(error_mask);
    secure_vector<byte> sym_key = hash.final();
-   secure_vector<byte> ciphertext = m_raw_pub_op.encrypt(message_and_error_input.data(),
-                                                         message_and_error_input.size(), rng);
 
    return std::make_pair(ciphertext, sym_key);
    }
 
-
-McEliece_KEM_Decryptor::McEliece_KEM_Decryptor(const McEliece_PrivateKey& mce_key) :
-   m_raw_priv_op(mce_key)
-   {
-   }
+McEliece_KEM_Decryptor::McEliece_KEM_Decryptor(const McEliece_PrivateKey& key) : m_key(key) { }
 
 secure_vector<Botan::byte> McEliece_KEM_Decryptor::decrypt(const byte msg[], size_t msg_len)
    {
-   secure_vector<Botan::byte> message_and_error = m_raw_priv_op.decrypt(msg, msg_len);
+   secure_vector<byte> plaintext, error_mask;
+   mceliece_decrypt(plaintext, error_mask, msg, msg_len, m_key);
 
    SHA_512 hash;
-   hash.update(message_and_error);
+   hash.update(plaintext);
+   hash.update(error_mask);
 
    secure_vector<byte> sym_key = hash.final();
    return sym_key;