diff options
Diffstat (limited to 'comm/third_party/botan/src/lib/block/xtea/xtea.cpp')
-rw-r--r-- | comm/third_party/botan/src/lib/block/xtea/xtea.cpp | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/block/xtea/xtea.cpp b/comm/third_party/botan/src/lib/block/xtea/xtea.cpp new file mode 100644 index 0000000000..7d815529ff --- /dev/null +++ b/comm/third_party/botan/src/lib/block/xtea/xtea.cpp @@ -0,0 +1,134 @@ +/* +* XTEA +* (C) 1999-2009,2016 Jack Lloyd +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#include <botan/xtea.h> +#include <botan/loadstor.h> + +namespace Botan { + +/* +* XTEA Encryption +*/ +void XTEA::encrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const + { + verify_key_set(m_EK.empty() == false); + + const uint32_t* EK = &m_EK[0]; + + const size_t blocks4 = blocks / 4; + const size_t blocks_left = blocks % 4; + + BOTAN_PARALLEL_FOR(size_t i = 0; i < blocks4; i++) + { + uint32_t L0, R0, L1, R1, L2, R2, L3, R3; + load_be(in + 4*BLOCK_SIZE*i, L0, R0, L1, R1, L2, R2, L3, R3); + + for(size_t r = 0; r != 32; ++r) + { + L0 += (((R0 << 4) ^ (R0 >> 5)) + R0) ^ EK[2*r]; + L1 += (((R1 << 4) ^ (R1 >> 5)) + R1) ^ EK[2*r]; + L2 += (((R2 << 4) ^ (R2 >> 5)) + R2) ^ EK[2*r]; + L3 += (((R3 << 4) ^ (R3 >> 5)) + R3) ^ EK[2*r]; + + R0 += (((L0 << 4) ^ (L0 >> 5)) + L0) ^ EK[2*r+1]; + R1 += (((L1 << 4) ^ (L1 >> 5)) + L1) ^ EK[2*r+1]; + R2 += (((L2 << 4) ^ (L2 >> 5)) + L2) ^ EK[2*r+1]; + R3 += (((L3 << 4) ^ (L3 >> 5)) + L3) ^ EK[2*r+1]; + } + + store_be(out + 4*BLOCK_SIZE*i, L0, R0, L1, R1, L2, R2, L3, R3); + } + + BOTAN_PARALLEL_FOR(size_t i = 0; i < blocks_left; ++i) + { + uint32_t L, R; + load_be(in + BLOCK_SIZE*(4*blocks4+i), L, R); + + for(size_t r = 0; r != 32; ++r) + { + L += (((R << 4) ^ (R >> 5)) + R) ^ EK[2*r]; + R += (((L << 4) ^ (L >> 5)) + L) ^ EK[2*r+1]; + } + + store_be(out + BLOCK_SIZE*(4*blocks4+i), L, R); + } + } + +/* +* XTEA Decryption +*/ +void XTEA::decrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const + { + verify_key_set(m_EK.empty() == false); + + const uint32_t* EK = &m_EK[0]; + + const size_t blocks4 = blocks / 4; + const size_t blocks_left = blocks % 4; + + BOTAN_PARALLEL_FOR(size_t i = 0; i < blocks4; i++) + { + uint32_t L0, R0, L1, R1, L2, R2, L3, R3; + load_be(in + 4*BLOCK_SIZE*i, L0, R0, L1, R1, L2, R2, L3, R3); + + for(size_t r = 0; r != 32; ++r) + { + R0 -= (((L0 << 4) ^ (L0 >> 5)) + L0) ^ EK[63 - 2*r]; + R1 -= (((L1 << 4) ^ (L1 >> 5)) + L1) ^ EK[63 - 2*r]; + R2 -= (((L2 << 4) ^ (L2 >> 5)) + L2) ^ EK[63 - 2*r]; + R3 -= (((L3 << 4) ^ (L3 >> 5)) + L3) ^ EK[63 - 2*r]; + + L0 -= (((R0 << 4) ^ (R0 >> 5)) + R0) ^ EK[62 - 2*r]; + L1 -= (((R1 << 4) ^ (R1 >> 5)) + R1) ^ EK[62 - 2*r]; + L2 -= (((R2 << 4) ^ (R2 >> 5)) + R2) ^ EK[62 - 2*r]; + L3 -= (((R3 << 4) ^ (R3 >> 5)) + R3) ^ EK[62 - 2*r]; + } + + store_be(out + 4*BLOCK_SIZE*i, L0, R0, L1, R1, L2, R2, L3, R3); + } + + BOTAN_PARALLEL_FOR(size_t i = 0; i < blocks_left; ++i) + { + uint32_t L, R; + load_be(in + BLOCK_SIZE*(4*blocks4+i), L, R); + + for(size_t r = 0; r != 32; ++r) + { + R -= (((L << 4) ^ (L >> 5)) + L) ^ m_EK[63 - 2*r]; + L -= (((R << 4) ^ (R >> 5)) + R) ^ m_EK[62 - 2*r]; + } + + store_be(out + BLOCK_SIZE*(4*blocks4+i), L, R); + } + } + +/* +* XTEA Key Schedule +*/ +void XTEA::key_schedule(const uint8_t key[], size_t) + { + m_EK.resize(64); + + secure_vector<uint32_t> UK(4); + for(size_t i = 0; i != 4; ++i) + UK[i] = load_be<uint32_t>(key, i); + + uint32_t D = 0; + for(size_t i = 0; i != 64; i += 2) + { + m_EK[i ] = D + UK[D % 4]; + D += 0x9E3779B9; + m_EK[i+1] = D + UK[(D >> 11) % 4]; + } + } + +void XTEA::clear() + { + zap(m_EK); + } + +} |