diff options
author | Jack Lloyd <[email protected]> | 2016-10-18 20:11:38 -0400 |
---|---|---|
committer | Jack Lloyd <[email protected]> | 2016-10-19 14:41:10 -0400 |
commit | 1caf3800efd03b222ff066c3bbea41ef44c9f513 (patch) | |
tree | 59edd7a1fe6f8d3fb8d2c900b8d5068de6f4a3d0 /src/lib/stream | |
parent | 3324f00a8b094c86cee1f5a59ec6fc746663bd7e (diff) |
Add SHAKE-128 as stream cipher
Updates NewHope to use that instead of the hard-coded SHAKE-128,
and adds toggle for BoringSSL compat mode using AES-128/CTR + SHA-256.
Diffstat (limited to 'src/lib/stream')
-rw-r--r-- | src/lib/stream/salsa20/salsa20.cpp | 2 | ||||
-rw-r--r-- | src/lib/stream/shake_cipher/info.txt | 1 | ||||
-rw-r--r-- | src/lib/stream/shake_cipher/shake_cipher.cpp | 75 | ||||
-rw-r--r-- | src/lib/stream/shake_cipher/shake_cipher.h | 64 | ||||
-rw-r--r-- | src/lib/stream/stream_cipher.cpp | 8 |
5 files changed, 149 insertions, 1 deletions
diff --git a/src/lib/stream/salsa20/salsa20.cpp b/src/lib/stream/salsa20/salsa20.cpp index f11fe5e59..0d8942789 100644 --- a/src/lib/stream/salsa20/salsa20.cpp +++ b/src/lib/stream/salsa20/salsa20.cpp @@ -163,7 +163,7 @@ void Salsa20::key_schedule(const byte key[], size_t length) } /* -* Return the name of this type +* Set the Salsa IV */ void Salsa20::set_iv(const byte iv[], size_t length) { diff --git a/src/lib/stream/shake_cipher/info.txt b/src/lib/stream/shake_cipher/info.txt new file mode 100644 index 000000000..53e6f5012 --- /dev/null +++ b/src/lib/stream/shake_cipher/info.txt @@ -0,0 +1 @@ +define SHAKE_CIPHER 20161018 diff --git a/src/lib/stream/shake_cipher/shake_cipher.cpp b/src/lib/stream/shake_cipher/shake_cipher.cpp new file mode 100644 index 000000000..5701e7802 --- /dev/null +++ b/src/lib/stream/shake_cipher/shake_cipher.cpp @@ -0,0 +1,75 @@ +/* +* SHAKE-128 +* (C) 2016 Jack Lloyd +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#include <botan/shake_cipher.h> +#include <botan/sha3.h> +#include <botan/loadstor.h> + +namespace Botan { + +SHAKE_128::SHAKE_128() : + m_state(25), + m_buffer((1600 - 256) / 8), + m_buf_pos(0) + {} + +void SHAKE_128::cipher(const byte in[], byte out[], size_t length) + { + while(length >= m_buffer.size() - m_buf_pos) + { + xor_buf(out, in, &m_buffer[m_buf_pos], m_buffer.size() - m_buf_pos); + length -= (m_buffer.size() - m_buf_pos); + in += (m_buffer.size() - m_buf_pos); + out += (m_buffer.size() - m_buf_pos); + + SHA_3::permute(m_state.data()); + copy_out_le(m_buffer.data(), m_buffer.size(), m_state.data()); + + m_buf_pos = 0; + } + xor_buf(out, in, &m_buffer[m_buf_pos], length); + m_buf_pos += length; + } + +void SHAKE_128::key_schedule(const byte key[], size_t length) + { + zeroise(m_state); + + for(size_t i = 0; i < length/8; ++i) + { + m_state[i] ^= load_le<uint64_t>(key, i); + } + + m_state[length/8] ^= 0x000000000000001F; + m_state[20] ^= 0x8000000000000000; + + SHA_3::permute(m_state.data()); + copy_out_le(m_buffer.data(), m_buffer.size(), m_state.data()); + } + +void SHAKE_128::clear() + { + zeroise(m_state); + zeroise(m_buffer); + m_buf_pos = 0; + } + +void SHAKE_128::set_iv(const byte[], size_t length) + { + /* + * This could be supported in some way (say, by treating iv as + * a prefix or suffix of the key). + */ + if(length != 0) + throw Invalid_IV_Length(name(), length); + } + +void SHAKE_128::seek(u64bit) + { + throw Not_Implemented("SHAKE_128::seek"); + } +} diff --git a/src/lib/stream/shake_cipher/shake_cipher.h b/src/lib/stream/shake_cipher/shake_cipher.h new file mode 100644 index 000000000..57eda58a4 --- /dev/null +++ b/src/lib/stream/shake_cipher/shake_cipher.h @@ -0,0 +1,64 @@ +/* +* SHAKE-128 as a stream cipher +* (C) 2016 Jack Lloyd +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#ifndef BOTAN_SHAKE128_CIPHER_H__ +#define BOTAN_SHAKE128_CIPHER_H__ + +#include <botan/stream_cipher.h> +#include <botan/secmem.h> + +namespace Botan { + +/** +* SHAKE-128 XOF presented as a stream cipher +*/ +class BOTAN_DLL SHAKE_128 final : public StreamCipher + { + public: + SHAKE_128(); + + /** + * Produce more XOF output + */ + void cipher(const byte in[], byte out[], size_t length) override; + + /** + * Seeking is not supported, this function will throw + */ + void seek(u64bit offset) override; + + /** + * IV not supported, this function will throw unless iv_len == 0 + */ + void set_iv(const byte iv[], size_t iv_len) override; + + bool valid_iv_length(size_t iv_len) const override { return (iv_len == 0); } + + /** + * In principle SHAKE can accept arbitrary length inputs, but this + * does not seem required for a stream cipher. + */ + Key_Length_Specification key_spec() const override + { + return Key_Length_Specification(16, 160, 8); + } + + void clear() override; + std::string name() const override { return "SHAKE-128"; } + StreamCipher* clone() const override { return new SHAKE_128; } + + private: + void key_schedule(const byte key[], size_t key_len) override; + + secure_vector<uint64_t> m_state; // internal state + secure_vector<byte> m_buffer; // ciphertext buffer + size_t m_buf_pos; // position in m_buffer + }; + +} + +#endif diff --git a/src/lib/stream/stream_cipher.cpp b/src/lib/stream/stream_cipher.cpp index cd6400d8f..7c41722a0 100644 --- a/src/lib/stream/stream_cipher.cpp +++ b/src/lib/stream/stream_cipher.cpp @@ -16,6 +16,10 @@ #include <botan/salsa20.h> #endif +#if defined(BOTAN_HAS_SHAKE_CIPHER) + #include <botan/shake_cipher.h> +#endif + #if defined(BOTAN_HAS_CTR_BE) #include <botan/ctr.h> #endif @@ -52,6 +56,10 @@ BOTAN_REGISTER_T_1LEN(StreamCipher, ChaCha, 20); BOTAN_REGISTER_T_NOARGS(StreamCipher, Salsa20); #endif +#if defined(BOTAN_HAS_SHAKE_CIPHER) +BOTAN_REGISTER_NAMED_T(StreamCipher, "SHAKE-128", SHAKE_128, make_new_T<SHAKE_128>); +#endif + #if defined(BOTAN_HAS_CTR_BE) BOTAN_REGISTER_NAMED_T(StreamCipher, "CTR-BE", CTR_BE, CTR_BE::make); #endif |