slon/System/Api/MD5.HC

144 lines
4.7 KiB
HolyC

/*
* Simple MD5 implementation
*
* https://gist.github.com/creationix/4710780
*/
U32 md5_r[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 };
// Use binary integer part of the sines of integers (in radians) as constants//
// Initialize variables:
U32 md5_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
};
// leftrotate function
U32 LEFTROTATE(U32 x, U32 c) { return (((x) << (c)) | ((x) >> (32 - (c)))); }
U0 md5(U8* initial_msg, U32 initial_len, U32* md5_h)
{
// These vars will contain the hash
U32 md5_h0, md5_h1, md5_h2, md5_h3;
// Message (to prepare)
U8* msg = NULL;
// Note: All variables are unsigned 32 bit and wrap modulo 2^32 when
// calculating
// r specifies the per-round shift amounts
md5_h0 = 0x67452301;
md5_h1 = 0xefcdab89;
md5_h2 = 0x98badcfe;
md5_h3 = 0x10325476;
// Pre-processing: adding a single 1 bit
// append "1" bit to message
/* Notice: the input bytes are considered as bits strings,
where the first bit is the most significant bit of the byte.[37] */
// Pre-processing: padding with zeros
// append "0" bit until message length in bit ≡ 448 (mod 512)
// append length mod (2 pow 64) to message
U32 new_len;
for (new_len = initial_len * 8 + 1; new_len % 512 != 448; new_len++)
;
new_len /= 8;
msg = CAlloc(new_len + 64, adam_task); // also appends "0" bits
// (we alloc also 64 extra bytes...)
MemCpy(msg, initial_msg, initial_len);
msg[initial_len] = 128; // write the "1" bit
U32 bits_len = 8 * initial_len; // note, we append the len
MemCpy(msg + new_len, &bits_len, 4); // in bits at the end of the buffer
// Process the message in successive 512-bit chunks:
// for each 512-bit chunk of message:
U32 offset;
for (offset = 0; offset < new_len; offset += (512 / 8)) {
// break chunk into sixteen 32-bit words w[j], 0 ≤ j ≤ 15
U32* w = (msg + offset)(U32*);
// Initialize hash value for this chunk:
U32 a = md5_h0;
U32 b = md5_h1;
U32 c = md5_h2;
U32 d = md5_h3;
// Main loop:
U32 i;
for (i = 0; i < 64; i++) {
U32 f, g;
if (i < 16) {
f = (b & c) | ((~b) & d);
g = i;
} else if (i < 32) {
f = (d & b) | ((~d) & c);
g = (5 * i + 1) % 16;
} else if (i < 48) {
f = b ^ c ^ d;
g = (3 * i + 5) % 16;
} else {
f = c ^ (b | (~d));
g = (7 * i) % 16;
}
U32 temp = d;
d = c;
c = b;
// printf("rotateLeft(%x + %x + %x + %x, %d)\n", a, f, k[i], w[g], r[i]);
b = b + LEFTROTATE((a + f + md5_k[i] + w[g]), md5_r[i]);
a = temp;
}
// Add this chunk's hash to result so far:
md5_h0 += a;
md5_h1 += b;
md5_h2 += c;
md5_h3 += d;
}
md5_h[0] = md5_h0;
md5_h[1] = md5_h1;
md5_h[2] = md5_h2;
md5_h[3] = md5_h3;
// cleanup
Free(msg);
}
U8* md5_string(U8* buf, I64 size)
{
U32 md5_h[4];
md5(buf, size, &md5_h[0]);
U8* str = CAlloc(33, adam_task);
StrPrint(str + StrLen(str), "%02x%02x%02x%02x", md5_h[0].u8[0],
md5_h[0].u8[1], md5_h[0].u8[2], md5_h[0].u8[3]);
StrPrint(str + StrLen(str), "%02x%02x%02x%02x", md5_h[1].u8[0],
md5_h[1].u8[1], md5_h[1].u8[2], md5_h[1].u8[3]);
StrPrint(str + StrLen(str), "%02x%02x%02x%02x", md5_h[2].u8[0],
md5_h[2].u8[1], md5_h[2].u8[2], md5_h[2].u8[3]);
StrPrint(str + StrLen(str), "%02x%02x%02x%02x", md5_h[3].u8[0],
md5_h[3].u8[1], md5_h[3].u8[2], md5_h[3].u8[3]);
return str;
}