diff options
author | lloyd <[email protected]> | 2006-05-18 18:33:19 +0000 |
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committer | lloyd <[email protected]> | 2006-05-18 18:33:19 +0000 |
commit | a2c99d3270eb73ef2db5704fc54356c6b75096f8 (patch) | |
tree | ad3d6c4fcc8dd0f403f8105598943616246fe172 /src/pbes2.cpp |
Initial checkin1.5.6
Diffstat (limited to 'src/pbes2.cpp')
-rw-r--r-- | src/pbes2.cpp | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/src/pbes2.cpp b/src/pbes2.cpp new file mode 100644 index 000000000..036acb675 --- /dev/null +++ b/src/pbes2.cpp @@ -0,0 +1,227 @@ +/************************************************* +* PKCS #5 PBES2 Source File * +* (C) 1999-2006 The Botan Project * +*************************************************/ + +#include <botan/pbe_pkcs.h> +#include <botan/parsing.h> +#include <botan/lookup.h> +#include <botan/rng.h> +#include <botan/asn1_obj.h> +#include <botan/oids.h> +#include <algorithm> +#include <memory> + +namespace Botan { + +/************************************************* +* Encrypt some bytes using PBES2 * +*************************************************/ +void PBE_PKCS5v20::write(const byte input[], u32bit length) + { + while(length) + { + u32bit put = std::min(DEFAULT_BUFFERSIZE, length); + pipe.write(input, length); + flush_pipe(true); + length -= put; + } + } + +/************************************************* +* Start encrypting with PBES2 * +*************************************************/ +void PBE_PKCS5v20::start_msg() + { + pipe.append(get_cipher(cipher, key, iv, direction)); + pipe.start_msg(); + if(pipe.message_count() > 1) + pipe.set_default_msg(pipe.default_msg() + 1); + } + +/************************************************* +* Finish encrypting with PBES2 * +*************************************************/ +void PBE_PKCS5v20::end_msg() + { + pipe.end_msg(); + flush_pipe(false); + pipe.reset(); + } + +/************************************************* +* Flush the pipe * +*************************************************/ +void PBE_PKCS5v20::flush_pipe(bool safe_to_skip) + { + if(safe_to_skip && pipe.remaining() < 64) + return; + + SecureVector<byte> buffer(DEFAULT_BUFFERSIZE); + while(pipe.remaining()) + { + u32bit got = pipe.read(buffer, buffer.size()); + send(buffer, got); + } + } + +/************************************************* +* Set the passphrase to use * +*************************************************/ +void PBE_PKCS5v20::set_key(const std::string& passphrase) + { + std::auto_ptr<S2K> pbkdf(get_s2k("PBKDF2(" + digest + ")")); + pbkdf->set_iterations(iterations); + pbkdf->change_salt(salt, salt.size()); + key = pbkdf->derive_key(key_length, passphrase).bits_of(); + } + +/************************************************* +* Create a new set of PBES2 parameters * +*************************************************/ +void PBE_PKCS5v20::new_params() + { + iterations = 2048; + key_length = max_keylength_of(cipher_algo); + salt.create(8); + iv.create(block_size_of(cipher_algo)); + Global_RNG::randomize(salt, salt.size()); + Global_RNG::randomize(iv, iv.size()); + } + +/************************************************* +* Encode PKCS#5 PBES2 parameters * +*************************************************/ +MemoryVector<byte> PBE_PKCS5v20::encode_params() const + { + return DER_Encoder() + .start_sequence() + .encode( + AlgorithmIdentifier("PKCS5.PBKDF2", + DER_Encoder() + .start_sequence() + .encode(salt, OCTET_STRING) + .encode(iterations) + .encode(key_length) + .end_sequence() + .get_contents() + ) + ) + .encode( + AlgorithmIdentifier(cipher, + DER_Encoder() + .encode(iv, OCTET_STRING) + .get_contents() + ) + ) + .end_sequence() + .get_contents(); + } + +/************************************************* +* Decode PKCS#5 PBES2 parameters * +*************************************************/ +void PBE_PKCS5v20::decode_params(DataSource& source) + { + AlgorithmIdentifier kdf_algo, enc_algo; + + BER_Decoder decoder(source); + BER_Decoder sequence = BER::get_subsequence(decoder); + BER::decode(sequence, kdf_algo); + BER::decode(sequence, enc_algo); + sequence.verify_end(); + + if(kdf_algo.oid == OIDS::lookup("PKCS5.PBKDF2")) + { + digest = "SHA-160"; + BER_Decoder pbkdf2_params(kdf_algo.parameters); + BER_Decoder algo_params = BER::get_subsequence(pbkdf2_params); + algo_params.decode(salt, OCTET_STRING); + algo_params.decode(iterations); + BER::decode_optional(algo_params, key_length, INTEGER, UNIVERSAL); + + algo_params.verify_end(); + } + else + throw Decoding_Error("PBE-PKCS5 v2.0: Unknown KDF algorithm " + + kdf_algo.oid.as_string()); + + cipher = OIDS::lookup(enc_algo.oid); + std::vector<std::string> cipher_spec = split_on(cipher, '/'); + if(cipher_spec.size() != 2) + throw Decoding_Error("PBE-PKCS5 v2.0: Invalid cipher spec " + cipher); + cipher_algo = deref_alias(cipher_spec[0]); + + if(!known_cipher(cipher_algo) || cipher_spec[1] != "CBC") + throw Decoding_Error("PBE-PKCS5 v2.0: Don't know param format for " + + cipher); + +#if 0 + BER_Decoder algo_params(enc_algo.parameters); + algo_params.decode(iv, OCTET_STRING); +#else + BER_Decoder(enc_algo.parameters).decode(iv, OCTET_STRING).verify_end(); +#endif + + if(key_length == 0) + key_length = max_keylength_of(cipher_algo); + + if(salt.size() < 8) + throw Decoding_Error("PBE-PKCS5 v2.0: Encoded salt is too small"); + } + +/************************************************* +* Return an OID for PBES2 * +*************************************************/ +OID PBE_PKCS5v20::get_oid() const + { + return OIDS::lookup("PBE-PKCS5v20"); + } + +/************************************************* +* Check if this is a known PBES2 cipher * +*************************************************/ +bool PBE_PKCS5v20::known_cipher(const std::string& algo) const + { + if(algo == "AES-128" || algo == "AES-192" || algo == "AES-256") + return true; + if(algo == "DES" || algo == "TripleDES") + return true; + return false; + } + +/************************************************* +* PKCS#5 v2.0 PBE Constructor * +*************************************************/ +PBE_PKCS5v20::PBE_PKCS5v20(const std::string& d_algo, + const std::string& c_algo) : + direction(ENCRYPTION), digest(deref_alias(d_algo)), cipher(c_algo) + { + std::vector<std::string> cipher_spec = split_on(cipher, '/'); + if(cipher_spec.size() != 2) + throw Invalid_Argument("PBE-PKCS5 v2.0: Invalid cipher spec " + cipher); + cipher_algo = deref_alias(cipher_spec[0]); + const std::string cipher_mode = cipher_spec[1]; + + if(!have_block_cipher(cipher_algo)) + throw Algorithm_Not_Found(cipher_algo); + if(!have_hash(digest)) + throw Algorithm_Not_Found(digest); + + if(!known_cipher(cipher_algo)) + throw Invalid_Argument("PBE-PKCS5 v2.0: Invalid cipher " + cipher); + if(cipher_mode != "CBC") + throw Invalid_Argument("PBE-PKCS5 v2.0: Invalid cipher " + cipher); + if(digest != "SHA-160") + throw Invalid_Argument("PBE-PKCS5 v2.0: Invalid digest " + digest); + } + +/************************************************* +* PKCS#5 v2.0 PBE Constructor * +*************************************************/ +PBE_PKCS5v20::PBE_PKCS5v20(DataSource& params) : direction(DECRYPTION) + { + decode_params(params); + } + +} |