This is xnu-10002.1.13. See this file in:
```/*
*  md5.c
*  Adapted for perf_index from ccmd5_ltc.c in corecrypto
*
*  Created by Fabrice Gautier on 12/3/10.
*
*/

#include "md5.h"

#include <stdint.h>
#include <string.h>

#define CCMD5_BLOCK_SIZE 64

#define F(x, y, z)  (z ^ (x & (y ^ z)))
#define G(x, y, z)  (y ^ (z & (y ^ x)))
#define H(x, y, z)  (x^y^z)
#define I(x, y, z)  (y^(x|(~z)))

#define CC_ROLc(X, s) (((X) << (s)) | ((X) >> (32 - (s))))

#define FF(a, b, c, d, M, s, t) \
a = (a + F(b,c,d) + M + t); a = CC_ROLc(a, s) + b;

#define GG(a, b, c, d, M, s, t) \
a = (a + G(b,c,d) + M + t); a = CC_ROLc(a, s) + b;

#define HH(a, b, c, d, M, s, t) \
a = (a + H(b,c,d) + M + t); a = CC_ROLc(a, s) + b;

#define II(a, b, c, d, M, s, t) \
a = (a + I(b,c,d) + M + t); a = CC_ROLc(a, s) + b;

static void
md5_compress(uint32_t *state, unsigned long nblocks, const void *in)
{
uint32_t i, W[16], a, b, c, d;
uint32_t *s = state;
const unsigned char *buf = in;

while (nblocks--) {
/* copy the state into 512-bits into W[0..15] */
for (i = 0; i < 16; i++) {
W[i] = ((uint32_t*)buf)[i];
}

/* copy state */
a = s[0];
b = s[1];
c = s[2];
d = s[3];

FF(a, b, c, d, W[0], 7, 0xd76aa478)
FF(d, a, b, c, W[1], 12, 0xe8c7b756)
FF(c, d, a, b, W[2], 17, 0x242070db)
FF(b, c, d, a, W[3], 22, 0xc1bdceee)
FF(a, b, c, d, W[4], 7, 0xf57c0faf)
FF(d, a, b, c, W[5], 12, 0x4787c62a)
FF(c, d, a, b, W[6], 17, 0xa8304613)
FF(b, c, d, a, W[7], 22, 0xfd469501)
FF(a, b, c, d, W[8], 7, 0x698098d8)
FF(d, a, b, c, W[9], 12, 0x8b44f7af)
FF(c, d, a, b, W[10], 17, 0xffff5bb1)
FF(b, c, d, a, W[11], 22, 0x895cd7be)
FF(a, b, c, d, W[12], 7, 0x6b901122)
FF(d, a, b, c, W[13], 12, 0xfd987193)
FF(c, d, a, b, W[14], 17, 0xa679438e)
FF(b, c, d, a, W[15], 22, 0x49b40821)
GG(a, b, c, d, W[1], 5, 0xf61e2562)
GG(d, a, b, c, W[6], 9, 0xc040b340)
GG(c, d, a, b, W[11], 14, 0x265e5a51)
GG(b, c, d, a, W[0], 20, 0xe9b6c7aa)
GG(a, b, c, d, W[5], 5, 0xd62f105d)
GG(d, a, b, c, W[10], 9, 0x02441453)
GG(c, d, a, b, W[15], 14, 0xd8a1e681)
GG(b, c, d, a, W[4], 20, 0xe7d3fbc8)
GG(a, b, c, d, W[9], 5, 0x21e1cde6)
GG(d, a, b, c, W[14], 9, 0xc33707d6)
GG(c, d, a, b, W[3], 14, 0xf4d50d87)
GG(b, c, d, a, W[8], 20, 0x455a14ed)
GG(a, b, c, d, W[13], 5, 0xa9e3e905)
GG(d, a, b, c, W[2], 9, 0xfcefa3f8)
GG(c, d, a, b, W[7], 14, 0x676f02d9)
GG(b, c, d, a, W[12], 20, 0x8d2a4c8a)
HH(a, b, c, d, W[5], 4, 0xfffa3942)
HH(d, a, b, c, W[8], 11, 0x8771f681)
HH(c, d, a, b, W[11], 16, 0x6d9d6122)
HH(b, c, d, a, W[14], 23, 0xfde5380c)
HH(a, b, c, d, W[1], 4, 0xa4beea44)
HH(d, a, b, c, W[4], 11, 0x4bdecfa9)
HH(c, d, a, b, W[7], 16, 0xf6bb4b60)
HH(b, c, d, a, W[10], 23, 0xbebfbc70)
HH(a, b, c, d, W[13], 4, 0x289b7ec6)
HH(d, a, b, c, W[0], 11, 0xeaa127fa)
HH(c, d, a, b, W[3], 16, 0xd4ef3085)
HH(b, c, d, a, W[6], 23, 0x04881d05)
HH(a, b, c, d, W[9], 4, 0xd9d4d039)
HH(d, a, b, c, W[12], 11, 0xe6db99e5)
HH(c, d, a, b, W[15], 16, 0x1fa27cf8)
HH(b, c, d, a, W[2], 23, 0xc4ac5665)
II(a, b, c, d, W[0], 6, 0xf4292244)
II(d, a, b, c, W[7], 10, 0x432aff97)
II(c, d, a, b, W[14], 15, 0xab9423a7)
II(b, c, d, a, W[5], 21, 0xfc93a039)
II(a, b, c, d, W[12], 6, 0x655b59c3)
II(d, a, b, c, W[3], 10, 0x8f0ccc92)
II(c, d, a, b, W[10], 15, 0xffeff47d)
II(b, c, d, a, W[1], 21, 0x85845dd1)
II(a, b, c, d, W[8], 6, 0x6fa87e4f)
II(d, a, b, c, W[15], 10, 0xfe2ce6e0)
II(c, d, a, b, W[6], 15, 0xa3014314)
II(b, c, d, a, W[13], 21, 0x4e0811a1)
II(a, b, c, d, W[4], 6, 0xf7537e82)
II(d, a, b, c, W[11], 10, 0xbd3af235)
II(c, d, a, b, W[2], 15, 0x2ad7d2bb)
II(b, c, d, a, W[9], 21, 0xeb86d391)

/* store state */
s[0] += a;
s[1] += b;
s[2] += c;
s[3] += d;

buf += CCMD5_BLOCK_SIZE;
}
}

void
md5_hash(uint8_t *message, uint64_t len, uint32_t *hash)
{
hash[0] = 0x67452301;
hash[1] = 0xEFCDAB89;
hash[3] = 0x10325476;

md5_compress(hash, len / 64, message);

uint32_t blockbuff[16];
uint8_t *byteptr = (uint8_t*)blockbuff;

int left = len % 64;
memcpy(byteptr, message + len - left, left);

byteptr[left] = 0x80;
left++;
if (64 - left >= 8) {
bzero(byteptr + left, 56 - left);
} else {
memset(byteptr + left, 0, 64 - left);
md5_compress(hash, 1, blockbuff);
bzero(blockbuff, 56);
}
blockbuff[14] = (uint32_t)(len << 3);
blockbuff[15] = (uint32_t)(len >> 29);
md5_compress(hash, 1, blockbuff);
}
```