diff options
Diffstat (limited to 'src/stream/salsa20')
| -rw-r--r-- | src/stream/salsa20/salsa20.cpp | 92 |
1 files changed, 26 insertions, 66 deletions
diff --git a/src/stream/salsa20/salsa20.cpp b/src/stream/salsa20/salsa20.cpp index 0243149f1..7238bdcb8 100644 --- a/src/stream/salsa20/salsa20.cpp +++ b/src/stream/salsa20/salsa20.cpp @@ -14,6 +14,14 @@ namespace Botan { namespace { +#define SALSA20_QUARTER_ROUND(x1, x2, x3, x4) \ + do { \ + x2 ^= rotate_left(x1 + x4, 7); \ + x3 ^= rotate_left(x2 + x1, 9); \ + x4 ^= rotate_left(x3 + x2, 13); \ + x1 ^= rotate_left(x4 + x3, 18); \ + } while(0) + /* * Generate HSalsa20 cipher stream (for XSalsa20 IV setup) */ @@ -38,39 +46,15 @@ void hsalsa20(u32bit output[8], const u32bit input[16]) for(u32bit i = 0; i != 10; ++i) { - x04 ^= rotate_left(x00 + x12, 7); - x08 ^= rotate_left(x04 + x00, 9); - x12 ^= rotate_left(x08 + x04, 13); - x00 ^= rotate_left(x12 + x08, 18); - x09 ^= rotate_left(x05 + x01, 7); - x13 ^= rotate_left(x09 + x05, 9); - x01 ^= rotate_left(x13 + x09, 13); - x05 ^= rotate_left(x01 + x13, 18); - x14 ^= rotate_left(x10 + x06, 7); - x02 ^= rotate_left(x14 + x10, 9); - x06 ^= rotate_left(x02 + x14, 13); - x10 ^= rotate_left(x06 + x02, 18); - x03 ^= rotate_left(x15 + x11, 7); - x07 ^= rotate_left(x03 + x15, 9); - x11 ^= rotate_left(x07 + x03, 13); - x15 ^= rotate_left(x11 + x07, 18); - - x01 ^= rotate_left(x00 + x03, 7); - x02 ^= rotate_left(x01 + x00, 9); - x03 ^= rotate_left(x02 + x01, 13); - x00 ^= rotate_left(x03 + x02, 18); - x06 ^= rotate_left(x05 + x04, 7); - x07 ^= rotate_left(x06 + x05, 9); - x04 ^= rotate_left(x07 + x06, 13); - x05 ^= rotate_left(x04 + x07, 18); - x11 ^= rotate_left(x10 + x09, 7); - x08 ^= rotate_left(x11 + x10, 9); - x09 ^= rotate_left(x08 + x11, 13); - x10 ^= rotate_left(x09 + x08, 18); - x12 ^= rotate_left(x15 + x14, 7); - x13 ^= rotate_left(x12 + x15, 9); - x14 ^= rotate_left(x13 + x12, 13); - x15 ^= rotate_left(x14 + x13, 18); + SALSA20_QUARTER_ROUND(x00, x04, x08, x12); + SALSA20_QUARTER_ROUND(x05, x09, x13, x01); + SALSA20_QUARTER_ROUND(x10, x14, x02, x06); + SALSA20_QUARTER_ROUND(x15, x03, x07, x11); + + SALSA20_QUARTER_ROUND(x00, x01, x02, x03); + SALSA20_QUARTER_ROUND(x05, x06, x07, x04); + SALSA20_QUARTER_ROUND(x10, x11, x08, x09); + SALSA20_QUARTER_ROUND(x15, x12, x13, x14); } output[0] = x00; @@ -107,39 +91,15 @@ void salsa20(byte output[64], const u32bit input[16]) for(u32bit i = 0; i != 10; ++i) { - x04 ^= rotate_left(x00 + x12, 7); - x08 ^= rotate_left(x04 + x00, 9); - x12 ^= rotate_left(x08 + x04, 13); - x00 ^= rotate_left(x12 + x08, 18); - x09 ^= rotate_left(x05 + x01, 7); - x13 ^= rotate_left(x09 + x05, 9); - x01 ^= rotate_left(x13 + x09, 13); - x05 ^= rotate_left(x01 + x13, 18); - x14 ^= rotate_left(x10 + x06, 7); - x02 ^= rotate_left(x14 + x10, 9); - x06 ^= rotate_left(x02 + x14, 13); - x10 ^= rotate_left(x06 + x02, 18); - x03 ^= rotate_left(x15 + x11, 7); - x07 ^= rotate_left(x03 + x15, 9); - x11 ^= rotate_left(x07 + x03, 13); - x15 ^= rotate_left(x11 + x07, 18); - - x01 ^= rotate_left(x00 + x03, 7); - x02 ^= rotate_left(x01 + x00, 9); - x03 ^= rotate_left(x02 + x01, 13); - x00 ^= rotate_left(x03 + x02, 18); - x06 ^= rotate_left(x05 + x04, 7); - x07 ^= rotate_left(x06 + x05, 9); - x04 ^= rotate_left(x07 + x06, 13); - x05 ^= rotate_left(x04 + x07, 18); - x11 ^= rotate_left(x10 + x09, 7); - x08 ^= rotate_left(x11 + x10, 9); - x09 ^= rotate_left(x08 + x11, 13); - x10 ^= rotate_left(x09 + x08, 18); - x12 ^= rotate_left(x15 + x14, 7); - x13 ^= rotate_left(x12 + x15, 9); - x14 ^= rotate_left(x13 + x12, 13); - x15 ^= rotate_left(x14 + x13, 18); + SALSA20_QUARTER_ROUND(x00, x04, x08, x12); + SALSA20_QUARTER_ROUND(x05, x09, x13, x01); + SALSA20_QUARTER_ROUND(x10, x14, x02, x06); + SALSA20_QUARTER_ROUND(x15, x03, x07, x11); + + SALSA20_QUARTER_ROUND(x00, x01, x02, x03); + SALSA20_QUARTER_ROUND(x05, x06, x07, x04); + SALSA20_QUARTER_ROUND(x10, x11, x08, x09); + SALSA20_QUARTER_ROUND(x15, x12, x13, x14); } store_le(x00 + input[ 0], output + 4 * 0); |