diff options
| -rw-r--r-- | src/lib/pubkey/mce/info.txt | 1 | ||||
| -rw-r--r-- | src/lib/pubkey/mce/mce_kem.cpp | 65 | ||||
| -rw-r--r-- | src/lib/pubkey/mce/mce_kem.h | 45 | ||||
| -rw-r--r-- | src/tests/test_mceliece.cpp | 89 |
4 files changed, 179 insertions, 21 deletions
diff --git a/src/lib/pubkey/mce/info.txt b/src/lib/pubkey/mce/info.txt index 6c0da2199..bc4249422 100644 --- a/src/lib/pubkey/mce/info.txt +++ b/src/lib/pubkey/mce/info.txt @@ -6,6 +6,7 @@ gf2m_rootfind_dcmp.h gf2m_small_m.h goppa_code.h mce_overbeck_cca2.h +mce_kem.h mceliece.h mceliece_key.h polyn_gf2m.h diff --git a/src/lib/pubkey/mce/mce_kem.cpp b/src/lib/pubkey/mce/mce_kem.cpp new file mode 100644 index 000000000..31dc2cfe2 --- /dev/null +++ b/src/lib/pubkey/mce/mce_kem.cpp @@ -0,0 +1,65 @@ +/** + * (C) 2014 cryptosource GmbH + * (C) 2014 Falko Strenzke [email protected] + * + * Distributed under the terms of the Botan license + * + */ + +#include <botan/mce_kem.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()) + { + } + +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[0], plaintext.size() ); + + // 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(); + + SHA_512 hash; + hash.update(message_and_error_input); + secure_vector<byte> sym_key = hash.final(); + secure_vector<byte> ciphertext = m_raw_pub_op.encrypt(&message_and_error_input[0], + 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) + { + } + +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[0], msg_len ); + + SHA_512 hash; + hash.update(message_and_error); + + secure_vector<byte> sym_key = hash.final(); + return sym_key; + } + +} diff --git a/src/lib/pubkey/mce/mce_kem.h b/src/lib/pubkey/mce/mce_kem.h new file mode 100644 index 000000000..4e46a0fab --- /dev/null +++ b/src/lib/pubkey/mce/mce_kem.h @@ -0,0 +1,45 @@ +/** + * (C) 2014 cryptosource GmbH + * (C) 2014 Falko Strenzke [email protected] + * + * Distributed under the terms of the Botan license + * + */ + +#ifndef BOTAN_MCE_KEM_H__ +#define BOTAN_MCE_KEM_H__ + +#include <botan/mceliece.h> +#include <utility> + +namespace Botan { + +class BOTAN_DLL McEliece_KEM_Encryptor + { + public: + McEliece_KEM_Encryptor(const McEliece_PublicKey& public_key); + + /** + * returns the pair (mceliece ciphertext, symmetric key) + */ + std::pair<secure_vector<byte>, secure_vector<byte>> encrypt(RandomNumberGenerator& rng); + + private: + McEliece_Public_Operation m_raw_pub_op; + }; + +class BOTAN_DLL McEliece_KEM_Decryptor + { + public: + McEliece_KEM_Decryptor(const McEliece_PrivateKey& mce_key); + + /** + * returns the derived 512-bit symmetric key + */ + secure_vector<Botan::byte> decrypt(const byte msg[], size_t msg_len); + private: + McEliece_Private_Operation m_raw_priv_op; + }; +} + +#endif /* h-guard */ diff --git a/src/tests/test_mceliece.cpp b/src/tests/test_mceliece.cpp index 8246e219b..dddf93b94 100644 --- a/src/tests/test_mceliece.cpp +++ b/src/tests/test_mceliece.cpp @@ -9,9 +9,11 @@ #include <botan/auto_rng.h> #include <botan/hex.h> #include <iostream> -#include <memory> #include <botan/mce_overbeck_cca2.h> +#include <botan/mce_kem.h> + +#include <memory> using namespace Botan; @@ -20,6 +22,8 @@ using namespace Botan; namespace { +const size_t MCE_RUNS = 10; + size_t test_mceliece_message_parts(RandomNumberGenerator& rng, size_t code_length, size_t error_weight) { secure_vector<gf2m> err_pos1 = create_random_error_positions(code_length, error_weight, rng); @@ -49,7 +53,6 @@ size_t test_mceliece_message_parts(RandomNumberGenerator& rng, size_t code_lengt return 0; } - size_t test_mceliece_overbeck(RandomNumberGenerator& rng, size_t code_length, size_t t ) { McEliece_PrivateKey sk1(rng, code_length, t); @@ -133,6 +136,58 @@ size_t test_mceliece_overbeck(RandomNumberGenerator& rng, size_t code_length, si return err_cnt; } +size_t test_mceliece_kem(RandomNumberGenerator& rng, u32bit code_length, u32bit t) + { + size_t fails = 0; + + McEliece_PrivateKey sk1(rng, code_length, t); + McEliece_PublicKey& pk1 = dynamic_cast<McEliece_PrivateKey&>(sk1); + + const std::vector<byte> pk_enc = pk1.x509_subject_public_key(); + const secure_vector<byte> sk_enc = sk1.pkcs8_private_key(); + + McEliece_PublicKey pk(pk_enc); + McEliece_PrivateKey sk(sk_enc); + + if(pk1 != pk) + { + std::cout << "decoded McEliece public key differs from original one" << std::endl; + ++fails; + } + + if(sk1 != sk) + { + std::cout << "decoded McEliece private key differs from original one" << std::endl; + ++fails; + } + + if(!sk.check_key(rng, false)) + { + std::cout << "error calling check key on McEliece key" << std::endl; + ++fails; + } + + McEliece_KEM_Encryptor pub_op(pk); + McEliece_KEM_Decryptor priv_op(sk); + + for(size_t i = 0; i != MCE_RUNS; i++) + { + const std::pair<secure_vector<byte>,secure_vector<byte> > ciphertext__sym_key = pub_op.encrypt(rng); + const secure_vector<byte>& ciphertext = ciphertext__sym_key.first; + const secure_vector<byte>& sym_key_encr = ciphertext__sym_key.second; + + const secure_vector<byte> sym_key_decr = priv_op.decrypt(&ciphertext[0], ciphertext.size()); + + if(sym_key_encr != sym_key_decr) + { + std::cout << "mce KEM test failed, error during encryption/decryption" << std::endl; + ++fails; + } + } + + return fails; + } + size_t test_mceliece_raw(RandomNumberGenerator& rng, size_t code_length, size_t t) { McEliece_PrivateKey sk(rng, code_length, t); @@ -142,7 +197,7 @@ size_t test_mceliece_raw(RandomNumberGenerator& rng, size_t code_length, size_t McEliece_Public_Operation pub_op(*p_pk, code_length ); size_t err_cnt = 0; - for(size_t i = 0; i < 100; i++) + for(size_t i = 0; i != MCE_RUNS; i++) { secure_vector<byte> plaintext((p_pk->get_message_word_bit_length()+7)/8); rng.randomize(&plaintext[0], plaintext.size() - 1); @@ -188,24 +243,6 @@ size_t test_mceliece() { AutoSeeded_RNG rng; - - /* - size_t key_gen_loop_limit = 10000; - for(size_t i = 0; i < key_gen_loop_limit; i++) - { - if(i % 100 == 0) - { - std::cout << "max key gen test : iter " << i << " of " << key_gen_loop_limit << std::endl; - } - if( test_mceliece_overbeck(rng, 2048, 33)) - { - std::cout << "error in overbeck test" << std::endl; - return 1; - } - - } - */ - size_t err_cnt = 0; size_t params__n__t_min_max[] = { 256, 5, 15, @@ -247,6 +284,16 @@ size_t test_mceliece() try { + err_cnt += test_mceliece_kem(rng, code_length, t); + } + catch(std::exception& e) + { + std::cout << e.what(); + err_cnt++; + } + + try + { // otherwise conversion not applicable because k=dimension would be too small if(code_length >= 2048) err_cnt += test_mceliece_overbeck(rng, code_length, t); |