crc32.cpp

#include "sysconfig.h"
#include "sysdeps.h"

#include "crc32.h"

static unsigned long crc_table32[256];
static unsigned short crc_table16[256];
static void make_crc_table (void)
{
	unsigned long c;
	unsigned short w;
	int n, k;
	for (n = 0; n < 256; n++) {
		c = (unsigned long)n;
		w = n << 8;
		for (k = 0; k < 8; k++) {
			c = (c >> 1) ^ (c & 1 ? 0xedb88320 : 0);
			w = (w << 1) ^ ((w & 0x8000) ? 0x1021 : 0);
		}
		crc_table32[n] = c;
		crc_table16[n] = w;
	}
}
uae_u32 get_crc32_val (uae_u8 v, uae_u32 crc)
{
	if (!crc_table32[1])
		make_crc_table();
	crc ^= 0xffffffff;
	crc = crc_table32[(crc ^ v) & 0xff] ^ (crc >> 8);
	return crc ^ 0xffffffff;
}
uae_u32 get_crc32 (void *vbuf, int len)
{
	uae_u8 *buf = (uae_u8*)vbuf;
	uae_u32 crc;
	if (!crc_table32[1])
		make_crc_table();
	crc = 0xffffffff;
	while (len-- > 0)
		crc = crc_table32[(crc ^ (*buf++)) & 0xff] ^ (crc >> 8);
	return crc ^ 0xffffffff;
}
uae_u16 get_crc16 (void *vbuf, int len)
{
	uae_u8 *buf = (uae_u8*)vbuf;
	uae_u16 crc;
	if (!crc_table32[1])
		make_crc_table();
	crc = 0xffff;
	while (len-- > 0)
		crc = (crc << 8) ^ crc_table16[((crc >> 8) ^ (*buf++)) & 0xff];
	return crc;
}

#ifndef GET_UINT32_BE
#define GET_UINT32_BE(n,b,i)                            \
{                                                       \
	(n) = ( (unsigned long) (b)[(i)    ] << 24 )        \
	| ( (unsigned long) (b)[(i) + 1] << 16 )        \
	| ( (unsigned long) (b)[(i) + 2] <<  8 )        \
	| ( (unsigned long) (b)[(i) + 3]       );       \
}
#endif
#ifndef PUT_UINT32_BE
#define PUT_UINT32_BE(n,b,i)                            \
{                                                       \
	(b)[(i)    ] = (unsigned char) ( (n) >> 24 );       \
	(b)[(i) + 1] = (unsigned char) ( (n) >> 16 );       \
	(b)[(i) + 2] = (unsigned char) ( (n) >>  8 );       \
	(b)[(i) + 3] = (unsigned char) ( (n)       );       \
}
#endif

typedef struct
{
	unsigned long total[2];     /*!< number of bytes processed  */
	unsigned long state[5];     /*!< intermediate digest state  */
	unsigned char buffer[64];   /*!< data block being processed */
}
sha1_context;

static void sha1_starts( sha1_context *ctx )
{
	ctx->total[0] = 0;
	ctx->total[1] = 0;

	ctx->state[0] = 0x67452301;
	ctx->state[1] = 0xEFCDAB89;
	ctx->state[2] = 0x98BADCFE;
	ctx->state[3] = 0x10325476;
	ctx->state[4] = 0xC3D2E1F0;
}

static void sha1_process( sha1_context *ctx, unsigned char data[64] )
{
	unsigned long temp, W[16], A, B, C, D, E;

	GET_UINT32_BE( W[0],  data,  0 );
	GET_UINT32_BE( W[1],  data,  4 );
	GET_UINT32_BE( W[2],  data,  8 );
	GET_UINT32_BE( W[3],  data, 12 );
	GET_UINT32_BE( W[4],  data, 16 );
	GET_UINT32_BE( W[5],  data, 20 );
	GET_UINT32_BE( W[6],  data, 24 );
	GET_UINT32_BE( W[7],  data, 28 );
	GET_UINT32_BE( W[8],  data, 32 );
	GET_UINT32_BE( W[9],  data, 36 );
	GET_UINT32_BE( W[10], data, 40 );
	GET_UINT32_BE( W[11], data, 44 );
	GET_UINT32_BE( W[12], data, 48 );
	GET_UINT32_BE( W[13], data, 52 );
	GET_UINT32_BE( W[14], data, 56 );
	GET_UINT32_BE( W[15], data, 60 );

#define S(x,n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n)))

#define R(t)                                            \
	(                                                       \
	temp = W[(t -  3) & 0x0F] ^ W[(t - 8) & 0x0F] ^     \
	W[(t - 14) & 0x0F] ^ W[ t      & 0x0F],      \
	( W[t & 0x0F] = S(temp,1) )                         \
	)

#define P(a,b,c,d,e,x)                                  \
	{                                                       \
	e += S(a,5) + F(b,c,d) + K + x; b = S(b,30);        \
	}

	A = ctx->state[0];
	B = ctx->state[1];
	C = ctx->state[2];
	D = ctx->state[3];
	E = ctx->state[4];

#define F(x,y,z) (z ^ (x & (y ^ z)))
#define K 0x5A827999

	P( A, B, C, D, E, W[0]  );
	P( E, A, B, C, D, W[1]  );
	P( D, E, A, B, C, W[2]  );
	P( C, D, E, A, B, W[3]  );
	P( B, C, D, E, A, W[4]  );
	P( A, B, C, D, E, W[5]  );
	P( E, A, B, C, D, W[6]  );
	P( D, E, A, B, C, W[7]  );
	P( C, D, E, A, B, W[8]  );
	P( B, C, D, E, A, W[9]  );
	P( A, B, C, D, E, W[10] );
	P( E, A, B, C, D, W[11] );
	P( D, E, A, B, C, W[12] );
	P( C, D, E, A, B, W[13] );
	P( B, C, D, E, A, W[14] );
	P( A, B, C, D, E, W[15] );
	P( E, A, B, C, D, R(16) );
	P( D, E, A, B, C, R(17) );
	P( C, D, E, A, B, R(18) );
	P( B, C, D, E, A, R(19) );

#undef K
#undef F

#define F(x,y,z) (x ^ y ^ z)
#define K 0x6ED9EBA1

	P( A, B, C, D, E, R(20) );
	P( E, A, B, C, D, R(21) );
	P( D, E, A, B, C, R(22) );
	P( C, D, E, A, B, R(23) );
	P( B, C, D, E, A, R(24) );
	P( A, B, C, D, E, R(25) );
	P( E, A, B, C, D, R(26) );
	P( D, E, A, B, C, R(27) );
	P( C, D, E, A, B, R(28) );
	P( B, C, D, E, A, R(29) );
	P( A, B, C, D, E, R(30) );
	P( E, A, B, C, D, R(31) );
	P( D, E, A, B, C, R(32) );
	P( C, D, E, A, B, R(33) );
	P( B, C, D, E, A, R(34) );
	P( A, B, C, D, E, R(35) );
	P( E, A, B, C, D, R(36) );
	P( D, E, A, B, C, R(37) );
	P( C, D, E, A, B, R(38) );
	P( B, C, D, E, A, R(39) );

#undef K
#undef F

#define F(x,y,z) ((x & y) | (z & (x | y)))
#define K 0x8F1BBCDC

	P( A, B, C, D, E, R(40) );
	P( E, A, B, C, D, R(41) );
	P( D, E, A, B, C, R(42) );
	P( C, D, E, A, B, R(43) );
	P( B, C, D, E, A, R(44) );
	P( A, B, C, D, E, R(45) );
	P( E, A, B, C, D, R(46) );
	P( D, E, A, B, C, R(47) );
	P( C, D, E, A, B, R(48) );
	P( B, C, D, E, A, R(49) );
	P( A, B, C, D, E, R(50) );
	P( E, A, B, C, D, R(51) );
	P( D, E, A, B, C, R(52) );
	P( C, D, E, A, B, R(53) );
	P( B, C, D, E, A, R(54) );
	P( A, B, C, D, E, R(55) );
	P( E, A, B, C, D, R(56) );
	P( D, E, A, B, C, R(57) );
	P( C, D, E, A, B, R(58) );
	P( B, C, D, E, A, R(59) );

#undef K
#undef F

#define F(x,y,z) (x ^ y ^ z)
#define K 0xCA62C1D6

	P( A, B, C, D, E, R(60) );
	P( E, A, B, C, D, R(61) );
	P( D, E, A, B, C, R(62) );
	P( C, D, E, A, B, R(63) );
	P( B, C, D, E, A, R(64) );
	P( A, B, C, D, E, R(65) );
	P( E, A, B, C, D, R(66) );
	P( D, E, A, B, C, R(67) );
	P( C, D, E, A, B, R(68) );
	P( B, C, D, E, A, R(69) );
	P( A, B, C, D, E, R(70) );
	P( E, A, B, C, D, R(71) );
	P( D, E, A, B, C, R(72) );
	P( C, D, E, A, B, R(73) );
	P( B, C, D, E, A, R(74) );
	P( A, B, C, D, E, R(75) );
	P( E, A, B, C, D, R(76) );
	P( D, E, A, B, C, R(77) );
	P( C, D, E, A, B, R(78) );
	P( B, C, D, E, A, R(79) );

#undef K
#undef F

	ctx->state[0] += A;
	ctx->state[1] += B;
	ctx->state[2] += C;
	ctx->state[3] += D;
	ctx->state[4] += E;
}

/*
* SHA-1 process buffer
*/
static void sha1_update( sha1_context *ctx, unsigned char *input, int ilen )
{
	int fill;
	unsigned long left;

	if( ilen <= 0 )
		return;

	left = ctx->total[0] & 0x3F;
	fill = 64 - left;

	ctx->total[0] += ilen;
	ctx->total[0] &= 0xFFFFFFFF;

	if( ctx->total[0] < (unsigned long) ilen )
		ctx->total[1]++;

	if( left && ilen >= fill )
	{
		memcpy( (void *) (ctx->buffer + left),
			(void *) input, fill );
		sha1_process( ctx, ctx->buffer );
		input += fill;
		ilen  -= fill;
		left = 0;
	}

	while( ilen >= 64 )
	{
		sha1_process( ctx, input );
		input += 64;
		ilen  -= 64;
	}

	if( ilen > 0 )
	{
		memcpy( (void *) (ctx->buffer + left),
			(void *) input, ilen );
	}
}

static const unsigned char sha1_padding[64] =
{
	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};

/*
* SHA-1 final digest
*/
static void sha1_finish( sha1_context *ctx, unsigned char output[20] )
{
	unsigned long last, padn;
	unsigned long high, low;
	unsigned char msglen[8];

	high = ( ctx->total[0] >> 29 )
		| ( ctx->total[1] <<  3 );
	low  = ( ctx->total[0] <<  3 );

	PUT_UINT32_BE( high, msglen, 0 );
	PUT_UINT32_BE( low,  msglen, 4 );

	last = ctx->total[0] & 0x3F;
	padn = ( last < 56 ) ? ( 56 - last ) : ( 120 - last );

	sha1_update( ctx, (unsigned char *) sha1_padding, padn );
	sha1_update( ctx, msglen, 8 );

	PUT_UINT32_BE( ctx->state[0], output,  0 );
	PUT_UINT32_BE( ctx->state[1], output,  4 );
	PUT_UINT32_BE( ctx->state[2], output,  8 );
	PUT_UINT32_BE( ctx->state[3], output, 12 );
	PUT_UINT32_BE( ctx->state[4], output, 16 );
}

void get_sha1 (void *vinput, int len, void *vout)
{
	uae_u8 *input = (uae_u8*)vinput;
	uae_u8 *out = (uae_u8*)vout;
	sha1_context ctx;

	sha1_starts( &ctx );
	sha1_update( &ctx, input, len );
	sha1_finish( &ctx, out );
}
const TCHAR *get_sha1_txt (void *vinput, int len)
{
	uae_u8 *input = (uae_u8*)vinput;
	static TCHAR outtxt[SHA1_SIZE * 2 + 1];
	uae_u8 out[SHA1_SIZE];
	int i;
	TCHAR *p;

	p = outtxt;
	get_sha1 (input, len, out);
	for (i = 0; i < SHA1_SIZE; i++) {
		_stprintf (p, _T("%02X"), out[i]);
		p += 2;
	}
	*p = 0;
	return outtxt;
}