diff options
author | lloyd <[email protected]> | 2008-10-01 14:36:27 +0000 |
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committer | lloyd <[email protected]> | 2008-10-01 14:36:27 +0000 |
commit | 06e35ed5375028f246f57b99ccf639e8ed317b35 (patch) | |
tree | 32021a79d1617a147f7fa7ac29c1eae60f9024ce /src/pubkey/dlies/dlies.cpp | |
parent | 9320b5e5c1b64894a6ff8797f392b57dfd72dea3 (diff) |
Rename pk dir to pubkey, avoids tab-completion collision with pk_pad
Diffstat (limited to 'src/pubkey/dlies/dlies.cpp')
-rw-r--r-- | src/pubkey/dlies/dlies.cpp | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/src/pubkey/dlies/dlies.cpp b/src/pubkey/dlies/dlies.cpp new file mode 100644 index 000000000..2a2f33925 --- /dev/null +++ b/src/pubkey/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; + } + +} |