/*
* Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include "inner.h"
#define F(B, C, D) ((((C) ^ (D)) & (B)) ^ (D))
#define G(B, C, D) ((((C) ^ (B)) & (D)) ^ (C))
#define H(B, C, D) ((B) ^ (C) ^ (D))
#define I(B, C, D) ((C) ^ ((B) | ~(D)))
#define ROTL(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
/* see inner.h */
const uint32_t br_md5_IV[4] = {
0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476
};
static const uint32_t K[64] = {
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 const unsigned char MP[48] = {
1, 6, 11, 0, 5, 10, 15, 4, 9, 14, 3, 8, 13, 2, 7, 12,
5, 8, 11, 14, 1, 4, 7, 10, 13, 0, 3, 6, 9, 12, 15, 2,
0, 7, 14, 5, 12, 3, 10, 1, 8, 15, 6, 13, 4, 11, 2, 9
};
/* see inner.h */
void
br_md5_round(const unsigned char *buf, uint32_t *val)
{
uint32_t m[16];
uint32_t a, b, c, d;
int i;
a = val[0];
b = val[1];
c = val[2];
d = val[3];
/* obsolete
for (i = 0; i < 16; i ++) {
m[i] = br_dec32le(buf + (i << 2));
}
*/
br_range_dec32le(m, 16, buf);
for (i = 0; i < 16; i += 4) {
a = b + ROTL(a + F(b, c, d) + m[i + 0] + K[i + 0], 7);
d = a + ROTL(d + F(a, b, c) + m[i + 1] + K[i + 1], 12);
c = d + ROTL(c + F(d, a, b) + m[i + 2] + K[i + 2], 17);
b = c + ROTL(b + F(c, d, a) + m[i + 3] + K[i + 3], 22);
}
for (i = 16; i < 32; i += 4) {
a = b + ROTL(a + G(b, c, d) + m[MP[i - 16]] + K[i + 0], 5);
d = a + ROTL(d + G(a, b, c) + m[MP[i - 15]] + K[i + 1], 9);
c = d + ROTL(c + G(d, a, b) + m[MP[i - 14]] + K[i + 2], 14);
b = c + ROTL(b + G(c, d, a) + m[MP[i - 13]] + K[i + 3], 20);
}
for (i = 32; i < 48; i += 4) {
a = b + ROTL(a + H(b, c, d) + m[MP[i - 16]] + K[i + 0], 4);
d = a + ROTL(d + H(a, b, c) + m[MP[i - 15]] + K[i + 1], 11);
c = d + ROTL(c + H(d, a, b) + m[MP[i - 14]] + K[i + 2], 16);
b = c + ROTL(b + H(c, d, a) + m[MP[i - 13]] + K[i + 3], 23);
}
for (i = 48; i < 64; i += 4) {
a = b + ROTL(a + I(b, c, d) + m[MP[i - 16]] + K[i + 0], 6);
d = a + ROTL(d + I(a, b, c) + m[MP[i - 15]] + K[i + 1], 10);
c = d + ROTL(c + I(d, a, b) + m[MP[i - 14]] + K[i + 2], 15);
b = c + ROTL(b + I(c, d, a) + m[MP[i - 13]] + K[i + 3], 21);
}
val[0] += a;
val[1] += b;
val[2] += c;
val[3] += d;
}
/* see bearssl.h */
void
br_md5_init(br_md5_context *cc)
{
cc->vtable = &br_md5_vtable;
memcpy(cc->val, br_md5_IV, sizeof cc->val);
cc->count = 0;
}
/* see bearssl.h */
void
br_md5_update(br_md5_context *cc, const void *data, size_t len)
{
const unsigned char *buf;
size_t ptr;
buf = data;
ptr = (size_t)cc->count & 63;
while (len > 0) {
size_t clen;
clen = 64 - ptr;
if (clen > len) {
clen = len;
}
memcpy(cc->buf + ptr, buf, clen);
ptr += clen;
buf += clen;
len -= clen;
cc->count += (uint64_t)clen;
if (ptr == 64) {
br_md5_round(cc->buf, cc->val);
ptr = 0;
}
}
}
/* see bearssl.h */
void
br_md5_out(const br_md5_context *cc, void *dst)
{
unsigned char buf[64];
uint32_t val[4];
size_t ptr;
ptr = (size_t)cc->count & 63;
memcpy(buf, cc->buf, ptr);
memcpy(val, cc->val, sizeof val);
buf[ptr ++] = 0x80;
if (ptr > 56) {
memset(buf + ptr, 0, 64 - ptr);
br_md5_round(buf, val);
memset(buf, 0, 56);
} else {
memset(buf + ptr, 0, 56 - ptr);
}
br_enc64le(buf + 56, cc->count << 3);
br_md5_round(buf, val);
br_range_enc32le(dst, val, 4);
}
/* see bearssl.h */
uint64_t
br_md5_state(const br_md5_context *cc, void *dst)
{
br_range_enc32le(dst, cc->val, 4);
return cc->count;
}
/* see bearssl.h */
void
br_md5_set_state(br_md5_context *cc, const void *stb, uint64_t count)
{
br_range_dec32le(cc->val, 4, stb);
cc->count = count;
}
/* see bearssl.h */
const br_hash_class br_md5_vtable = {
sizeof(br_md5_context),
BR_HASHDESC_ID(br_md5_ID)
| BR_HASHDESC_OUT(16)
| BR_HASHDESC_STATE(16)
| BR_HASHDESC_LBLEN(6)
| BR_HASHDESC_MD_PADDING,
(void (*)(const br_hash_class **))&br_md5_init,
(void (*)(const br_hash_class **, const void *, size_t))&br_md5_update,
(void (*)(const br_hash_class *const *, void *))&br_md5_out,
(uint64_t (*)(const br_hash_class *const *, void *))&br_md5_state,
(void (*)(const br_hash_class **, const void *, uint64_t))
&br_md5_set_state
};