diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/engine/core_engine/core_modes.cpp | 8 | ||||
-rw-r--r-- | src/filters/modes/cfb/cfb.cpp | 175 | ||||
-rw-r--r-- | src/filters/modes/cfb/cfb.h | 84 | ||||
-rw-r--r-- | src/filters/modes/cfb/info.txt | 5 | ||||
-rw-r--r-- | src/modes/cfb/cfb.cpp | 150 | ||||
-rw-r--r-- | src/modes/cfb/cfb.h | 91 | ||||
-rw-r--r-- | src/modes/cfb/info.txt | 1 |
7 files changed, 246 insertions, 268 deletions
diff --git a/src/engine/core_engine/core_modes.cpp b/src/engine/core_engine/core_modes.cpp index c2c34234f..e949d5f9b 100644 --- a/src/engine/core_engine/core_modes.cpp +++ b/src/engine/core_engine/core_modes.cpp @@ -16,7 +16,7 @@ #include <botan/cts.h> #endif -#if defined(BOTAN_HAS_CFB) +#if defined(BOTAN_HAS_MODE_CFB) #include <botan/cfb.h> #endif @@ -206,13 +206,13 @@ Keyed_Filter* get_cipher_mode(const BlockCipher* block_cipher, #endif -#if defined(BOTAN_HAS_CFB) +#if defined(BOTAN_HAS_MODE_CFB) if(mode_name == "CFB") { if(direction == ENCRYPTION) - return new CFB_Encryption(block_cipher->clone(), bits); + return new Transformation_Filter(new CFB_Encryption(block_cipher->clone(), bits)); else - return new CFB_Decryption(block_cipher->clone(), bits); + return new Transformation_Filter(new CFB_Decryption(block_cipher->clone(), bits)); } #endif diff --git a/src/filters/modes/cfb/cfb.cpp b/src/filters/modes/cfb/cfb.cpp deleted file mode 100644 index 2b7cca84a..000000000 --- a/src/filters/modes/cfb/cfb.cpp +++ /dev/null @@ -1,175 +0,0 @@ -/* -* CFB Mode -* (C) 1999-2007 Jack Lloyd -* -* Distributed under the terms of the Botan license -*/ - -#include <botan/cfb.h> -#include <botan/parsing.h> -#include <botan/internal/xor_buf.h> -#include <algorithm> - -namespace Botan { - -/* -* CFB Encryption Constructor -*/ -CFB_Encryption::CFB_Encryption(BlockCipher* ciph, size_t fback_bits) - { - cipher = ciph; - feedback = fback_bits ? fback_bits / 8: cipher->block_size(); - - buffer.resize(cipher->block_size()); - state.resize(cipher->block_size()); - position = 0; - - if(feedback == 0 || fback_bits % 8 != 0 || feedback > cipher->block_size()) - throw Invalid_Argument("CFB_Encryption: Invalid feedback size " + - std::to_string(fback_bits)); - } - -/* -* CFB Encryption Constructor -*/ -CFB_Encryption::CFB_Encryption(BlockCipher* ciph, - const SymmetricKey& key, - const InitializationVector& iv, - size_t fback_bits) - { - cipher = ciph; - feedback = fback_bits ? fback_bits / 8: cipher->block_size(); - - buffer.resize(cipher->block_size()); - state.resize(cipher->block_size()); - position = 0; - - if(feedback == 0 || fback_bits % 8 != 0 || feedback > cipher->block_size()) - throw Invalid_Argument("CFB_Encryption: Invalid feedback size " + - std::to_string(fback_bits)); - - set_key(key); - set_iv(iv); - } - -void CFB_Encryption::set_iv(const InitializationVector& iv) - { - if(!valid_iv_length(iv.length())) - throw Invalid_IV_Length(name(), iv.length()); - - state = iv.bits_of(); - zeroise(buffer); - position = 0; - - cipher->encrypt(&state[0], &buffer[0]); - } - -/* -* Encrypt data in CFB mode -*/ -void CFB_Encryption::write(const byte input[], size_t length) - { - while(length) - { - size_t xored = std::min(feedback - position, length); - xor_buf(&buffer[position], input, xored); - send(&buffer[position], xored); - input += xored; - length -= xored; - position += xored; - - if(position == feedback) - { - for(size_t j = 0; j != cipher->block_size() - feedback; ++j) - state[j] = state[j + feedback]; - - buffer_insert(state, cipher->block_size() - feedback, - &buffer[0], feedback); - - cipher->encrypt(state, buffer); - position = 0; - } - } - } - -/* -* CFB Decryption Constructor -*/ -CFB_Decryption::CFB_Decryption(BlockCipher* ciph, size_t fback_bits) - { - cipher = ciph; - feedback = fback_bits ? fback_bits / 8: cipher->block_size(); - - buffer.resize(cipher->block_size()); - state.resize(cipher->block_size()); - position = 0; - - if(feedback == 0 || fback_bits % 8 != 0 || feedback > cipher->block_size()) - throw Invalid_Argument("CFB_Decryption: Invalid feedback size " + - std::to_string(fback_bits)); - } - -/* -* CFB Decryption Constructor -*/ -CFB_Decryption::CFB_Decryption(BlockCipher* ciph, - const SymmetricKey& key, - const InitializationVector& iv, - size_t fback_bits) - { - cipher = ciph; - feedback = fback_bits ? fback_bits / 8: cipher->block_size(); - - buffer.resize(cipher->block_size()); - state.resize(cipher->block_size()); - position = 0; - - if(feedback == 0 || fback_bits % 8 != 0 || feedback > cipher->block_size()) - throw Invalid_Argument("CFB_Decryption: Invalid feedback size " + - std::to_string(fback_bits)); - - set_key(key); - set_iv(iv); - } - -void CFB_Decryption::set_iv(const InitializationVector& iv) - { - if(!valid_iv_length(iv.length())) - throw Invalid_IV_Length(name(), iv.length()); - - state = iv.bits_of(); - zeroise(buffer); - position = 0; - - cipher->encrypt(state, buffer); - } - -/* -* Decrypt data in CFB mode -*/ -void CFB_Decryption::write(const byte input[], size_t length) - { - while(length) - { - size_t xored = std::min(feedback - position, length); - xor_buf(&buffer[position], input, xored); - send(&buffer[position], xored); - buffer_insert(buffer, position, input, xored); - input += xored; - length -= xored; - position += xored; - if(position == feedback) - { - for(size_t j = 0; j != cipher->block_size() - feedback; ++j) - state[j] = state[j + feedback]; - - buffer_insert(state, cipher->block_size() - feedback, - &buffer[0], feedback); - - cipher->encrypt(state, buffer); - position = 0; - } - } - } - -} diff --git a/src/filters/modes/cfb/cfb.h b/src/filters/modes/cfb/cfb.h deleted file mode 100644 index 02154ebb9..000000000 --- a/src/filters/modes/cfb/cfb.h +++ /dev/null @@ -1,84 +0,0 @@ -/* -* CFB Mode -* (C) 1999-2007 Jack Lloyd -* -* Distributed under the terms of the Botan license -*/ - -#ifndef BOTAN_CFB_H__ -#define BOTAN_CFB_H__ - -#include <botan/block_cipher.h> -#include <botan/key_filt.h> - -namespace Botan { - -/** -* CFB Encryption -*/ -class BOTAN_DLL CFB_Encryption : public Keyed_Filter - { - public: - std::string name() const { return cipher->name() + "/CFB"; } - - void set_iv(const InitializationVector&); - - void set_key(const SymmetricKey& key) { cipher->set_key(key); } - - Key_Length_Specification key_spec() const override { return cipher->key_spec(); } - - bool valid_iv_length(size_t iv_len) const - { return (iv_len == cipher->block_size()); } - - CFB_Encryption(BlockCipher* cipher, size_t feedback = 0); - - CFB_Encryption(BlockCipher* cipher, - const SymmetricKey& key, - const InitializationVector& iv, - size_t feedback = 0); - - ~CFB_Encryption() { delete cipher; } - private: - void write(const byte[], size_t); - - BlockCipher* cipher; - secure_vector<byte> buffer, state; - size_t position, feedback; - }; - -/** -* CFB Decryption -*/ -class BOTAN_DLL CFB_Decryption : public Keyed_Filter - { - public: - std::string name() const { return cipher->name() + "/CFB"; } - - void set_iv(const InitializationVector&); - - void set_key(const SymmetricKey& key) { cipher->set_key(key); } - - Key_Length_Specification key_spec() const override { return cipher->key_spec(); } - - bool valid_iv_length(size_t iv_len) const - { return (iv_len == cipher->block_size()); } - - CFB_Decryption(BlockCipher* cipher, size_t feedback = 0); - - CFB_Decryption(BlockCipher* cipher, - const SymmetricKey& key, - const InitializationVector& iv, - size_t feedback = 0); - - ~CFB_Decryption() { delete cipher; } - private: - void write(const byte[], size_t); - - BlockCipher* cipher; - secure_vector<byte> buffer, state; - size_t position, feedback; - }; - -} - -#endif diff --git a/src/filters/modes/cfb/info.txt b/src/filters/modes/cfb/info.txt deleted file mode 100644 index eb2cc69ba..000000000 --- a/src/filters/modes/cfb/info.txt +++ /dev/null @@ -1,5 +0,0 @@ -define CFB - -<requires> -block -</requires> diff --git a/src/modes/cfb/cfb.cpp b/src/modes/cfb/cfb.cpp new file mode 100644 index 000000000..2edb917b4 --- /dev/null +++ b/src/modes/cfb/cfb.cpp @@ -0,0 +1,150 @@ +/* +* CFB Mode +* (C) 1999-2007,2013 Jack Lloyd +* +* Distributed under the terms of the Botan license +*/ + +#include <botan/cfb.h> +#include <botan/parsing.h> +#include <botan/internal/xor_buf.h> + +namespace Botan { + +CFB_Mode::CFB_Mode(BlockCipher* cipher, size_t feedback_bits) : + m_cipher(cipher), + m_feedback_bytes(feedback_bits ? feedback_bits / 8 : cipher->block_size()) + { + if(feedback_bits % 8 || feedback() > cipher->block_size()) + throw std::invalid_argument(name() + ": feedback bits " + + std::to_string(feedback_bits) + " not supported"); + } + +void CFB_Mode::clear() + { + m_cipher->clear(); + m_shift_register.clear(); + } + +std::string CFB_Mode::name() const + { + if(feedback() == cipher().block_size()) + return cipher().name() + "/CFB"; + else + return cipher().name() + "/CFB(" + std::to_string(feedback()*8) + ")"; + } + +size_t CFB_Mode::output_length(size_t input_length) const + { + return input_length; + } + +size_t CFB_Mode::update_granularity() const + { + return feedback(); + } + +size_t CFB_Mode::minimum_final_size() const + { + return 0; + } + +Key_Length_Specification CFB_Mode::key_spec() const + { + return cipher().key_spec(); + } + +size_t CFB_Mode::default_nonce_size() const + { + return cipher().block_size(); + } + +bool CFB_Mode::valid_nonce_length(size_t n) const + { + return (n == cipher().block_size()); + } + +void CFB_Mode::key_schedule(const byte key[], size_t length) + { + m_cipher->set_key(key, length); + } + +secure_vector<byte> CFB_Mode::start(const byte nonce[], size_t nonce_len) + { + if(!valid_nonce_length(nonce_len)) + throw Invalid_IV_Length(name(), nonce_len); + + m_shift_register.assign(nonce, nonce + nonce_len); + m_keystream_buf.resize(m_shift_register.size()); + cipher().encrypt(m_shift_register, m_keystream_buf); + + return secure_vector<byte>(); + } + +void CFB_Encryption::update(secure_vector<byte>& buffer, size_t offset) + { + BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane"); + size_t sz = buffer.size() - offset; + byte* buf = &buffer[offset]; + + const size_t BS = cipher().block_size(); + + secure_vector<byte>& state = shift_register(); + const size_t shift = feedback(); + + while(sz) + { + const size_t took = std::min(shift, sz); + xor_buf(&buf[0], &keystream_buf()[0], took); + + // Assumes feedback-sized block except for last input + copy_mem(&state[0], &state[shift], BS - shift); + copy_mem(&state[BS-shift], &buf[0], shift); + cipher().encrypt(state, keystream_buf()); + + buf += took; + sz -= took; + } + } + +void CFB_Encryption::finish(secure_vector<byte>& buffer, size_t offset) + { + update(buffer, offset); + } + +void CFB_Decryption::update(secure_vector<byte>& buffer, size_t offset) + { + BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane"); + size_t sz = buffer.size() - offset; + byte* buf = &buffer[offset]; + + const size_t BS = cipher().block_size(); + + secure_vector<byte>& state = shift_register(); + const size_t shift = feedback(); + + while(sz) + { + const size_t took = std::min(shift, sz); + + // first update shift register with ciphertext + copy_mem(&state[0], &state[shift], BS - shift); + copy_mem(&state[BS-shift], &buf[0], took); + + // then decrypt + xor_buf(&buf[0], &keystream_buf()[0], took); + + // then update keystream + cipher().encrypt(state, keystream_buf()); + + buf += took; + sz -= took; + } + } + +void CFB_Decryption::finish(secure_vector<byte>& buffer, size_t offset) + { + update(buffer, offset); + } + +} diff --git a/src/modes/cfb/cfb.h b/src/modes/cfb/cfb.h new file mode 100644 index 000000000..19e5b4bb0 --- /dev/null +++ b/src/modes/cfb/cfb.h @@ -0,0 +1,91 @@ +/* +* CFB mode +* (C) 1999-2007,2013 Jack Lloyd +* +* Distributed under the terms of the Botan license +*/ + +#ifndef BOTAN_MODE_CFB_H__ +#define BOTAN_MODE_CFB_H__ + +#include <botan/transform.h> +#include <botan/block_cipher.h> +#include <botan/mode_pad.h> +#include <memory> + +namespace Botan { + +/** +* CFB Mode +*/ +class CFB_Mode : public Transformation + { + public: + secure_vector<byte> start(const byte nonce[], size_t nonce_len) override; + + std::string name() const override; + + size_t update_granularity() const override; + + size_t minimum_final_size() const override; + + Key_Length_Specification key_spec() const override; + + size_t output_length(size_t input_length) const override; + + size_t default_nonce_size() const override; + + bool valid_nonce_length(size_t n) const override; + + void clear(); + protected: + CFB_Mode(BlockCipher* cipher, size_t feedback_bits); + + const BlockCipher& cipher() const { return *m_cipher; } + + size_t feedback() const { return m_feedback_bytes; } + + secure_vector<byte>& shift_register() { return m_shift_register; } + + secure_vector<byte>& keystream_buf() { return m_keystream_buf; } + + private: + void key_schedule(const byte key[], size_t length) override; + + std::unique_ptr<BlockCipher> m_cipher; + secure_vector<byte> m_shift_register; + secure_vector<byte> m_keystream_buf; + size_t m_feedback_bytes; + }; + +/** +* CFB Encryption +*/ +class BOTAN_DLL CFB_Encryption : public CFB_Mode + { + public: + CFB_Encryption(BlockCipher* cipher, size_t feedback_bits) : + CFB_Mode(cipher, feedback_bits) {} + + void update(secure_vector<byte>& blocks, size_t offset) override; + + void finish(secure_vector<byte>& final_block, size_t offset) override; + }; + +/** +* CFB Decryption +*/ +class BOTAN_DLL CFB_Decryption : public CFB_Mode + { + public: + CFB_Decryption(BlockCipher* cipher, size_t feedback_bits) : + CFB_Mode(cipher, feedback_bits) {} + + void update(secure_vector<byte>& blocks, size_t offset) override; + + void finish(secure_vector<byte>& final_block, size_t offset) override; + }; + +} + +#endif diff --git a/src/modes/cfb/info.txt b/src/modes/cfb/info.txt new file mode 100644 index 000000000..797459180 --- /dev/null +++ b/src/modes/cfb/info.txt @@ -0,0 +1 @@ +define MODE_CFB |