-/* MD5 message digest
- * Author: John Tsiombikas <nuclear@member.fsf.org>
- *
- * This software is public domain. Feel free to use it any way you like.
- *
- * If public domain is not applicable in your part of the world, you may use
- * this under the terms of the Creative Commons CC-0 license:
- * http://creativecommons.org/publicdomain/zero/1.0/
- */
-#include <stdio.h>
-#include <string.h>
-#include "md5.h"
-
-#define BLOCKSZ 64
-
-static const int shifttab[] = {
- 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
-};
-
-static const uint32_t sintab[] = {
- 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
- 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
- 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
- 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
- 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
- 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
- 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
- 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
- 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
- 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
- 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05,
- 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
- 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
- 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
- 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
- 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
-};
-
-static void sum_block(uint32_t *blk, uint32_t *sum);
-static uint32_t rol(uint32_t x, int s);
-
-void md5_begin(struct md5_state *md)
-{
- md->sum[0] = 0x67452301;
- md->sum[1] = 0xefcdab89;
- md->sum[2] = 0x98badcfe;
- md->sum[3] = 0x10325476;
- md->len = 0;
- md->bblen = 0;
-}
-
-void md5_msg(struct md5_state *md, void *msg, int msg_size)
-{
- int pending, sz;
-
- while(msg_size) {
- pending = BLOCKSZ - md->bblen;
- sz = msg_size > pending ? pending : msg_size;
-
- memcpy(md->blockbuf + md->bblen, msg, sz);
- msg = (char*)msg + sz;
- md->bblen += sz;
- msg_size -= sz;
-
- if(md->bblen >= BLOCKSZ) {
- sum_block((uint32_t*)md->blockbuf, md->sum);
- md->bblen = 0;
- md->len += BLOCKSZ * 8;
- }
- }
-}
-
-static void sum_block(uint32_t *blk, uint32_t *sum)
-{
- int i, f, g;
- int a = sum[0];
- int b = sum[1];
- int c = sum[2];
- int d = sum[3];
-
- for(i=0; i<64; i++) {
- switch(i >> 4) {
- case 0:
- f = d ^ (b & (c ^ d));
- g = i;
- break;
-
- case 1:
- f = c ^ (d & (b ^ c));
- g = (i * 5 + 1) & 0xf;
- break;
-
- case 2:
- f = b ^ c ^ d;
- g = (i * 3 + 5) & 0xf;
- break;
-
- case 3:
- f = c ^ (b | ~d);
- g = (i * 7) & 0xf;
- }
-
- f += a + sintab[i] + blk[g];
- a = d;
- d = c;
- c = b;
- b += rol(f, shifttab[i]);
- }
-
- sum[0] += a;
- sum[1] += b;
- sum[2] += c;
- sum[3] += d;
-}
-
-static uint32_t rol(uint32_t x, int s)
-{
- return (x << s) | (x >> (32 - s));
-}
-
-void md5_end(struct md5_state *md)
-{
- md->len += md->bblen * 8;
- md->blockbuf[md->bblen++] = 0x80; /* append 1-bit plus 8 zeros padding */
-
- if(md->bblen > BLOCKSZ - 8) {
- /* pad to BLOCKSZ, sum, then continue with further padding */
- memset(md->blockbuf + md->bblen, 0, BLOCKSZ - md->bblen);
- sum_block((uint32_t*)md->blockbuf, md->sum);
- md->bblen = 0;
- }
-
- /* pad to BLOCKSZ - 8 */
- memset(md->blockbuf + md->bblen, 0, BLOCKSZ - 8 - md->bblen);
-
- /* add the length */
- *(uint64_t*)(md->blockbuf + BLOCKSZ - 8) = md->len;
-
- /* then sum for the last time */
- sum_block((uint32_t*)md->blockbuf, md->sum);
-}
-
-const char *md5_sumstr(struct md5_state *md)
-{
- int i;
- unsigned char *sum = (unsigned char*)md->sum;
- char *s = (char*)md->blockbuf;
-
- for(i=0; i<16; i++) {
- s += sprintf(s, "%02x", sum[i]);
- }
- return (char*)md->blockbuf;
-}