diff options
| -rw-r--r-- | src/utils/xor_buf.h | 42 |
1 files changed, 32 insertions, 10 deletions
diff --git a/src/utils/xor_buf.h b/src/utils/xor_buf.h index 0a71aef3e..975ad0af6 100644 --- a/src/utils/xor_buf.h +++ b/src/utils/xor_buf.h @@ -1,7 +1,7 @@ -/************************************************* -* Xor Operations Header File * -* (C) 1999-2008 Jack Lloyd * -*************************************************/ +/** +* XOR operations +* (C) 1999-2008 Jack Lloyd +*/ #ifndef BOTAN_XOR_BUF_H__ #define BOTAN_XOR_BUF_H__ @@ -10,9 +10,12 @@ namespace Botan { -/************************************************* -* XOR Arrays * -*************************************************/ +/** +* XOR arrays. Postcondition out[i] = in[i] ^ out[i] forall i = 0...length +* @param out the input/output buffer +* @param in the read-only input buffer +* @param length the length of the buffers +*/ inline void xor_buf(byte out[], const byte in[], u32bit length) { while(length >= 8) @@ -32,9 +35,13 @@ inline void xor_buf(byte out[], const byte in[], u32bit length) out[j] ^= in[j]; } -/************************************************* -* XOR Arrays * -*************************************************/ +/** +* XOR arrays. Postcondition out[i] = in[i] ^ in2[i] forall i = 0...length +* @param out the output buffer +* @param in the first input buffer +* @param in2 the second output buffer +* @param length the length of the three buffers +*/ inline void xor_buf(byte out[], const byte in[], const byte in2[], @@ -60,6 +67,21 @@ inline void xor_buf(byte out[], out[j] = in[j] ^ in2[j]; } +/** +* Xor values into buffer +*/ +inline u32bit xor_into_buf(byte buf[], u32bit buf_i, u32bit length, + const void* in_void, u32bit in_len) + { + const byte* in = static_cast<const byte*>(in_void); + for(u32bit i = 0; i != in_len; ++i) + { + buf[buf_i] ^= in[i]; + buf_i = (buf_i + 1) % length; + } + return buf_i; + } + } #endif |