Avoid shuffling the data around in memory so much

diff --git a/source/sha2.cpp b/source/sha2.cpp
index 3823643c323e6b5eb3b70707eecf56227b5b7e7c..c0cb1a172be384c80a12146eb66f21fd80004f4c 100644 (file)
--- a/source/sha2.cpp
+++ b/source/sha2.cpp
@@ -79,8 +79,8 @@ void SHA2<C>::process_block(const char *data)
        for(unsigned i=16; i<Constants::N_ROUNDS; ++i)
        {
                WordType *block = message_blocks+i;
-               WordType s1 = (rotate_right(block[-2], sigma[9]) ^ rotate_right(block[-2], sigma[10]) ^ (block[-2]>>sigma[11]));
-               WordType s0 = (rotate_right(block[-15], sigma[6]) ^ rotate_right(block[-15], sigma[7]) ^ (block[-15]>>sigma[8]));
+               WordType s1 = rotate_right(block[-2], sigma[9]) ^ rotate_right(block[-2], sigma[10]) ^ (block[-2]>>sigma[11]);
+               WordType s0 = rotate_right(block[-15], sigma[6]) ^ rotate_right(block[-15], sigma[7]) ^ (block[-15]>>sigma[8]);
                *block =  s1+block[-7]+s0+block[-16];
        }
 
@@ -89,20 +89,24 @@ void SHA2<C>::process_block(const char *data)
 
        for(unsigned i=0; i<Constants::N_ROUNDS; ++i)
        {
-               WordType s1 = (rotate_right(values[4], sigma[3]) ^ rotate_right(values[4], sigma[4]) ^ rotate_right(values[4], sigma[5]));
-               WordType ch = ((values[4]&values[5]) ^ (~values[4]&values[6]));
-               WordType temp1 = values[7]+s1+ch+Constants::round_constants[i]+message_blocks[i];
-               WordType s0 = (rotate_right(values[0], sigma[0]) ^ rotate_right(values[0], sigma[1]) ^ rotate_right(values[0], sigma[2]));
-               WordType maj = ((values[0]&values[1]) ^ (values[0]&values[2]) ^ (values[1]&values[2]));
+               const WordType &a = values[(88-i)&7];
+               const WordType &b = values[(89-i)&7];
+               const WordType &c = values[(90-i)&7];
+               WordType &d = values[(91-i)&7];
+               const WordType &e = values[(92-i)&7];
+               const WordType &f = values[(93-i)&7];
+               const WordType &g = values[(94-i)&7];
+               WordType &h = values[(95-i)&7];
+
+               WordType s1 = rotate_right(e, sigma[3]) ^ rotate_right(e, sigma[4]) ^ rotate_right(e, sigma[5]);
+               WordType ch = (e&f) ^ (~e&g);
+               WordType temp1 = h+s1+ch+Constants::round_constants[i]+message_blocks[i];
+               WordType s0 = rotate_right(a, sigma[0]) ^ rotate_right(a, sigma[1]) ^ rotate_right(a, sigma[2]);
+               WordType maj = (a&b) ^ (a&c) ^ (b&c);
                WordType temp2 = s0+maj;
-               values[7] = values[6];
-               values[6] = values[5];
-               values[5] = values[4];
-               values[4] = values[3]+temp1;
-               values[3] = values[2];
-               values[2] = values[1];
-               values[1] = values[0];
-               values[0] = temp1+temp2;
+
+               d += temp1;       // Will be e next round
+               h = temp1+temp2;  // Will be a next round
        }
 
        for(unsigned i=0; i<8; ++i)