diff options
| -rw-r--r-- | toys/lsb/md5sum.c | 48 |
1 files changed, 25 insertions, 23 deletions
diff --git a/toys/lsb/md5sum.c b/toys/lsb/md5sum.c index 3b5571bb..ab43e7b9 100644 --- a/toys/lsb/md5sum.c +++ b/toys/lsb/md5sum.c @@ -46,6 +46,8 @@ GLOBALS( } buffer; ) +#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits)))) + // for(i=0; i<64; i++) md5table[i] = abs(sin(i+1))*(1<<32); But calculating // that involves not just floating point but pulling in -lm (and arguing with // C about whether 1<<32 is a valid thing to do on 32 bit platforms) so: @@ -64,44 +66,45 @@ static uint32_t md5table[64] = { 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391 }; +static const uint8_t md5rot[64] = { + 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, + 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, + 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, + 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21 +}; + // Mix next 64 bytes of data into md5 hash static void md5_transform(void) { - unsigned x[4], *b = (unsigned *)TT.buffer.c; + unsigned x[4], *b = TT.buffer.i; int i; memcpy(x, TT.state, sizeof(x)); for (i=0; i<64; i++) { - unsigned int in, a, rot, temp; - - a = (-i)&3; + unsigned int in, temp, swap; if (i<16) { in = i; - rot = 7+(5*(i&3)); - temp = x[(a+1)&3]; - temp = (temp & x[(a+2)&3]) | ((~temp) & x[(a+3)&3]); + temp = x[1]; + temp = (temp & x[2]) | ((~temp) & x[3]); } else if (i<32) { in = (1+(5*i))&15; - temp = (i&3)+1; - rot = temp*5; - if (temp&2) rot--; - temp = x[(a+3)&3]; - temp = (x[(a+1)&3] & temp) | (x[(a+2)&3] & ~temp); + temp = x[3]; + temp = (x[1] & temp) | (x[2] & ~temp); } else if (i<48) { - in = (5+(3*(i&15)))&15; - rot = i&3; - rot = 4+(5*rot)+((rot+1)&6); - temp = x[(a+1)&3] ^ x[(a+2)&3] ^ x[(a+3)&3]; + in = (3*i+5)&15; + temp = x[1] ^ x[2] ^ x[3]; } else { - in = (7*(i&15))&15; - rot = (i&3)+1; - rot = (5*rot)+(((rot+2)&2)>>1); - temp = x[(a+2)&3] ^ (x[(a+1)&3] | ~x[(a+3)&3]); + in = (7*i)&15; + temp = x[2] ^ (x[1] | ~x[3]); } - temp += x[a] + b[in] + md5table[i]; - x[a] = x[(a+1)&3] + ((temp<<rot) | (temp>>(32-rot))); + temp += x[0] + b[in] + md5table[i]; + swap = x[3]; + x[3] = x[2]; + x[2] = x[1]; + x[1] += rol(temp, md5rot[i]); + x[0] = swap; } for (i=0; i<4; i++) TT.state[i] += x[i]; } @@ -109,7 +112,6 @@ static void md5_transform(void) // Mix next 64 bytes of data into sha1 hash. static const unsigned rconsts[]={0x5A827999,0x6ED9EBA1,0x8F1BBCDC,0xCA62C1D6}; -#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits)))) static void sha1_transform(void) { |