winamp/Src/Plugins/Portable/pmp_ipod/sha1.c

/*
SHA-1 in C
By Steve Reid <steve@edmweb.com>
100% Public Domain

Test Vectors (from FIPS PUB 180-1)
"abc"
A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
A million repetitions of "a"
34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
*/

#define LITTLE_ENDIAN /* This should be #define'd if true. */
/* #define SHA1HANDSOFF * Copies data before messing with it. */

#include <stdio.h>
#include <string.h>

typedef struct {
	unsigned long state[5];
	unsigned long count[2];
	unsigned char buffer[64];
} SHA1_CTX;

void SHA1Transform(unsigned long state[5], unsigned char buffer[64]);
void SHA1Init(SHA1_CTX* context);
void SHA1Update(SHA1_CTX* context, unsigned char* data, unsigned int len);
void SHA1Final(unsigned char digest[20], SHA1_CTX* context);

#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))

/* blk0() and blk() perform the initial expand. */
/* I got the idea of expanding during the round function from SSLeay */
#ifdef LITTLE_ENDIAN
#define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
	|(rol(block->l[i],8)&0x00FF00FF))
#else
#define blk0(i) block->l[i]
#endif
#define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
	^block->l[(i+2)&15]^block->l[i&15],1))

/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
#define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);

/* Hash a single 512-bit block. This is the core of the algorithm. */

void SHA1Transform(unsigned long state[5], unsigned char buffer[64])
{
	unsigned long a, b, c, d, e;
	typedef union {
		unsigned char c[64];
		unsigned long l[16];
	} CHAR64LONG16;
	CHAR64LONG16* block;

	/*
	printf("SHA1Transform:\n");
	for (k = 0; k < 4; k++) {
		for (i = 0; i < 4; i++) {
			for (j = 0; j < 4; j++) {
				printf("%02X", buffer[k*16+i*4+j]);
			}
			putchar(' ');
		}
		putchar('\n');
	}
	printf("SHA1Transform (translated):\n");
		for (k = 0; k < 4; k++) {
			for (i = 0; i < 4; i++) {
				for (j = 0; j < 4; j++) {
					long x = buffer[k*16+i*4+j] & 0xFF;
					printf("%02X", cryptTable[x] & 0xFF);
				}
				putchar(' ');
			}
			putchar('\n');
		}
		*/

#ifdef SHA1HANDSOFF
	static unsigned char workspace[64];
	block = (CHAR64LONG16*)workspace;
	memcpy(block, buffer, 64);
#else
	block = (CHAR64LONG16*)buffer;
#endif
	/* Copy context->state[] to working vars */
	a = state[0];
	b = state[1];
	c = state[2];
	d = state[3];
	e = state[4];
	/* 4 rounds of 20 operations each. Loop unrolled. */
	R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3);
	R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7);
	R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11);
	R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15);
	R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);
	R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23);
	R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27);
	R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31);
	R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35);
	R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39);
	R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43);
	R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47);
	R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51);
	R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55);
	R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59);
	R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63);
	R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67);
	R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71);
	R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75);
	R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79);
	/* Add the working vars back into context.state[] */
	state[0] += a;
	state[1] += b;
	state[2] += c;
	state[3] += d;
	state[4] += e;
	/* Wipe variables */
	a = b = c = d = e = 0;
}


/* SHA1Init - Initialize new context */

void SHA1Init(SHA1_CTX* context)
{
	/* SHA1 initialization constants */
	context->state[0] = 0x67452301;
	context->state[1] = 0xEFCDAB89;
	context->state[2] = 0x98BADCFE;
	context->state[3] = 0x10325476;
	context->state[4] = 0xC3D2E1F0;
	context->count[0] = context->count[1] = 0;
}


/* Run your data through this. */

void SHA1Update(SHA1_CTX* context, unsigned char* data, unsigned int len)
{
	unsigned int i, j;

	j = (context->count[0] >> 3) & 63;
	if ((context->count[0] += len << 3) < (len << 3)) context->count[1]++;
	context->count[1] += (len >> 29);
	if ((j + len) > 63) {
		memcpy(&context->buffer[j], data, (i = 64-j));
		SHA1Transform(context->state, context->buffer);
		for ( ; i + 63 < len; i += 64) {
			SHA1Transform(context->state, &data[i]);
		}
		j = 0;
	}
	else i = 0;
	memcpy(&context->buffer[j], &data[i], len - i);
}


/* Add padding and return the message digest. */

void SHA1Final(unsigned char digest[20], SHA1_CTX* context)
{
	unsigned long i, j;
	unsigned char finalcount[8];

	for (i = 0; i < 8; i++) {
		finalcount[i] = (unsigned char)((context->count[(i >= 4 ? 0 : 1)]
		>> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
	}
	SHA1Update(context, (unsigned char *)"\200", 1);
	while ((context->count[0] & 504) != 448) {
		SHA1Update(context, (unsigned char *)"\0", 1);
	}
	SHA1Update(context, finalcount, 8);  /* Should cause a SHA1Transform() */
	for (i = 0; i < 20; i++) {
		digest[i] = (unsigned char)
			((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
	}
	/* Wipe variables */
	i = j = 0;
	memset(context->buffer, 0, 64);
	memset(context->state, 0, 20);
	memset(context->count, 0, 8);
	memset(&finalcount, 0, 8);
#ifdef SHA1HANDSOFF  /* make SHA1Transform overwrite it's own static vars */
	SHA1Transform(context->state, context->buffer);
#endif
}


/*************************************************************/

/*
int main(int argc, char** argv)
{
	int i, j;
	SHA1_CTX context;
	unsigned char digest[20], buffer[16384];
	FILE* file;

	if (argc > 2) {
		puts("Public domain SHA-1 implementation - by Steve Reid <steve@edmweb.com>");
		puts("Produces the SHA-1 hash of a file, or stdin if no file is specified.");
		exit(0);
	}
	if (argc < 2) {
		file = stdin;
	}
	else {
		if (!(file = fopen(argv[1], "rb"))) {
			fputs("Unable to open file.", stderr);
			exit(-1);
		}
	} 
	SHA1Init(&context);
	while (!feof(file)) {  /* note: what if ferror(file) 
		i = fread(buffer, 1, 16384, file);
		SHA1Update(&context, buffer, i);
	}
	SHA1Final(digest, &context);
	fclose(file);
	for (i = 0; i < 5; i++) {
		for (j = 0; j < 4; j++) {
			printf("%02X", digest[i*4+j]);
		}
		putchar(' ');
	}
	putchar('\n');
	exit(0);
}
*/