md32_common.h

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#endif
#define HOST_p_c2l(c,l,n)	{					\
			switch (n) {					\
			case 0: l =((unsigned long)(*((c)++)))<<24;	\
			case 1: l|=((unsigned long)(*((c)++)))<<16;	\
			case 2: l|=((unsigned long)(*((c)++)))<< 8;	\
			case 3: l|=((unsigned long)(*((c)++)));		\
				} }
#define HOST_p_c2l_p(c,l,sc,len) {					\
			switch (sc) {					\
			case 0: l =((unsigned long)(*((c)++)))<<24;	\
				if (--len == 0) break;			\
			case 1: l|=((unsigned long)(*((c)++)))<<16;	\
				if (--len == 0) break;			\
			case 2: l|=((unsigned long)(*((c)++)))<< 8;	\
				} }
/* NOTE the pointer is not incremented at the end of this */
#define HOST_c2l_p(c,l,n)	{					\
			l=0; (c)+=n;					\
			switch (n) {					\
			case 3: l =((unsigned long)(*(--(c))))<< 8;	\
			case 2: l|=((unsigned long)(*(--(c))))<<16;	\
			case 1: l|=((unsigned long)(*(--(c))))<<24;	\
				} }
#ifndef HOST_l2c
#define HOST_l2c(l,c)	(*((c)++)=(unsigned char)(((l)>>24)&0xff),	\
			 *((c)++)=(unsigned char)(((l)>>16)&0xff),	\
			 *((c)++)=(unsigned char)(((l)>> 8)&0xff),	\
			 *((c)++)=(unsigned char)(((l)    )&0xff),	\
			 l)
#endif

#elif defined(DATA_ORDER_IS_LITTLE_ENDIAN)

#if defined(__i386) || defined(__i386__) || defined(__x86_64) || defined(__x86_64__)
# ifndef B_ENDIAN
   /* See comment in DATA_ORDER_IS_BIG_ENDIAN section. */
#  define HOST_c2l(c,l)	((l)=*((const unsigned int *)(c)), (c)+=4, l)
#  define HOST_l2c(l,c)	(*((unsigned int *)(c))=(l), (c)+=4, l)
# endif
#endif

#ifndef HOST_c2l
#define HOST_c2l(c,l)	(l =(((unsigned long)(*((c)++)))    ),		\
			 l|=(((unsigned long)(*((c)++)))<< 8),		\
			 l|=(((unsigned long)(*((c)++)))<<16),		\
			 l|=(((unsigned long)(*((c)++)))<<24),		\
			 l)
#endif
#define HOST_p_c2l(c,l,n)	{					\
			switch (n) {					\
			case 0: l =((unsigned long)(*((c)++)));		\
			case 1: l|=((unsigned long)(*((c)++)))<< 8;	\
			case 2: l|=((unsigned long)(*((c)++)))<<16;	\
			case 3: l|=((unsigned long)(*((c)++)))<<24;	\
				} }
#define HOST_p_c2l_p(c,l,sc,len) {					\
			switch (sc) {					\
			case 0: l =((unsigned long)(*((c)++)));		\
				if (--len == 0) break;			\
			case 1: l|=((unsigned long)(*((c)++)))<< 8;	\
				if (--len == 0) break;			\
			case 2: l|=((unsigned long)(*((c)++)))<<16;	\
				} }
/* NOTE the pointer is not incremented at the end of this */
#define HOST_c2l_p(c,l,n)	{					\
			l=0; (c)+=n;					\
			switch (n) {					\
			case 3: l =((unsigned long)(*(--(c))))<<16;	\
			case 2: l|=((unsigned long)(*(--(c))))<< 8;	\
			case 1: l|=((unsigned long)(*(--(c))));		\
				} }
#ifndef HOST_l2c
#define HOST_l2c(l,c)	(*((c)++)=(unsigned char)(((l)    )&0xff),	\
			 *((c)++)=(unsigned char)(((l)>> 8)&0xff),	\
			 *((c)++)=(unsigned char)(((l)>>16)&0xff),	\
			 *((c)++)=(unsigned char)(((l)>>24)&0xff),	\
			 l)
#endif

#endif

/*
 * Time for some action:-)
 */

int HASH_UPDATE (HASH_CTX *c, const void *data_, size_t len)
	{
	const unsigned char *data=data_;
	register HASH_LONG * p;
	register HASH_LONG l;
	size_t sw,sc,ew,ec;

	if (len==0) return 1;

	l=(c->Nl+(((HASH_LONG)len)<<3))&0xffffffffUL;
	/* 95-05-24 eay Fixed a bug with the overflow handling, thanks to
	 * Wei Dai <[e-mail]> for pointing it out. */
	if (l < c->Nl) /* overflow */
		c->Nh++;
	c->Nh+=(len>>29);	/* might cause compiler warning on 16-bit */
	c->Nl=l;

	if (c->num != 0)
		{
		p=c->data;
		sw=c->num>>2;
		sc=c->num&0x03;

		if ((c->num+len) >= HASH_CBLOCK)
			{
			l=p[sw]; HOST_p_c2l(data,l,sc); p[sw++]=l;
			for (; sw<HASH_LBLOCK; sw++)
				{
				HOST_c2l(data,l); p[sw]=l;
				}
			HASH_BLOCK_HOST_ORDER (c,p,1);
			len-=(HASH_CBLOCK-c->num);
			c->num=0;
			/* drop through and do the rest */
			}
		else
			{
			c->num+=(unsigned int)len;
			if ((sc+len) < 4) /* ugly, add char's to a word */
				{
				l=p[sw]; HOST_p_c2l_p(data,l,sc,len); p[sw]=l;
				}
			else
				{
				ew=(c->num>>2);
				ec=(c->num&0x03);
				if (sc)
					l=p[sw];
				HOST_p_c2l(data,l,sc);
				p[sw++]=l;
				for (; sw < ew; sw++)
					{
					HOST_c2l(data,l); p[sw]=l;
					}
				if (ec)
					{
					HOST_c2l_p(data,l,ec); p[sw]=l;
					}
				}
			return 1;
			}
		}

	sw=len/HASH_CBLOCK;
	if (sw > 0)
		{
#if defined(HASH_BLOCK_DATA_ORDER_ALIGNED)
		/*
		 * Note that HASH_BLOCK_DATA_ORDER_ALIGNED gets defined
		 * only if sizeof(HASH_LONG)==4.
		 */
		if ((((size_t)data)%4) == 0)
			{
			/* data is properly aligned so that we can cast it: */
			HASH_BLOCK_DATA_ORDER_ALIGNED (c,(const HASH_LONG *)data,sw);
			sw*=HASH_CBLOCK;
			data+=sw;
			len-=sw;
			}
		else
#if !defined(HASH_BLOCK_DATA_ORDER)
			while (sw--)
				{
				memcpy (p=c->data,data,HASH_CBLOCK);
				HASH_BLOCK_DATA_ORDER_ALIGNED(c,p,1);
				data+=HASH_CBLOCK;
				len-=HASH_CBLOCK;
				}
#endif
#endif
#if defined(HASH_BLOCK_DATA_ORDER)
			{
			HASH_BLOCK_DATA_ORDER(c,data,sw);
			sw*=HASH_CBLOCK;
			data+=sw;
			len-=sw;
			}
#endif
		}

	if (len!=0)
		{
		p = c->data;
		c->num = len;
		ew=len>>2;	/* words to copy */
		ec=len&0x03;
		for (; ew; ew--,p++)
			{
			HOST_c2l(data,l); *p=l;
			}
		HOST_c2l_p(data,l,ec);
		*p=l;
		}
	return 1;
	}


void HASH_TRANSFORM (HASH_CTX *c, const unsigned char *data)
	{
#if defined(HASH_BLOCK_DATA_ORDER_ALIGNED)
	if ((((size_t)data)%4) == 0)
		/* data is properly aligned so that we can cast it: */
		HASH_BLOCK_DATA_ORDER_ALIGNED (c,(const HASH_LONG *)data,1);
	else
#if !defined(HASH_BLOCK_DATA_ORDER)
		{
		memcpy (c->data,data,HASH_CBLOCK);
		HASH_BLOCK_DATA_ORDER_ALIGNED (c,c->data,1);
		}
#endif
#endif
#if defined(HASH_BLOCK_DATA_ORDER)
	HASH_BLOCK_DATA_ORDER (c,data,1);
#endif
	}


int HASH_FINAL (unsigned char *md, HASH_CTX *c)
	{
	register HASH_LONG *p;
	register unsigned long l;
	register int i,j;
	static const unsigned char end[4]={0x80,0x00,0x00,0x00};
	const unsigned char *cp=end;

	/* c->num should definitly have room for at least one more byte. */
	p=c->data;
	i=c->num>>2;
	j=c->num&0x03;

#if 0
	/* purify often complains about the following line as an
	 * Uninitialized Memory Read.  While this can be true, the
	 * following p_c2l macro will reset l when that case is true.
	 * This is because j&0x03 contains the number of 'valid' bytes
	 * already in p[i].  If and only if j&0x03 == 0, the UMR will
	 * occur but this is also the only time p_c2l will do
	 * l= *(cp++) instead of l|= *(cp++)
	 * Many thanks to Alex Tang <[e-mail]> for pickup this
	 * 'potential bug' */
#ifdef PURIFY
	if (j==0) p[i]=0; /* Yeah, but that's not the way to fix it:-) */
#endif
	l=p[i];
#else
	l = (j==0) ? 0 : p[i];
#endif
	HOST_p_c2l(cp,l,j); p[i++]=l; /* i is the next 'undefined word' */

	if (i>(HASH_LBLOCK-2)) /* save room for Nl and Nh */
		{
		if (i<HASH_LBLOCK) p[i]=0;
		HASH_BLOCK_HOST_ORDER (c,p,1);
		i=0;
		}
	for (; i<(HASH_LBLOCK-2); i++)
		p[i]=0;

#if   defined(DATA_ORDER_IS_BIG_ENDIAN)
	p[HASH_LBLOCK-2]=c->Nh;
	p[HASH_LBLOCK-1]=c->Nl;
#elif defined(DATA_ORDER_IS_LITTLE_ENDIAN)
	p[HASH_LBLOCK-2]=c->Nl;
	p[HASH_LBLOCK-1]=c->Nh;
#endif
	HASH_BLOCK_HOST_ORDER (c,p,1);

#ifndef HASH_MAKE_STRING
#error "HASH_MAKE_STRING must be defined!"
#else
	HASH_MAKE_STRING(c,md);
#endif

	c->num=0;
	/* clear stuff, HASH_BLOCK may be leaving some stuff on the stack
	 * but I'm not worried :-)
	OPENSSL_cleanse((void *)c,sizeof(HASH_CTX));
	 */
	return 1;
	}

#ifndef MD32_REG_T
#define MD32_REG_T long
/*
 * This comment was originaly written for MD5, which is why it
 * discusses A-D. But it basically applies to all 32-bit digests,
 * which is why it was moved to common header file.
 *
 * In case you wonder why A-D are declared as long and not
 * as MD5_LONG. Doing so results in slight performance
 * boost on LP64 architectures. The catch is we don't
 * really care if 32 MSBs of a 64-bit register get polluted
 * with eventual overflows as we *save* only 32 LSBs in
 * *either* case. Now declaring 'em long excuses the compiler
 * from keeping 32 MSBs zeroed resulting in 13% performance
 * improvement under SPARC Solaris7/64 and 5% under AlphaLinux.
 * Well, to be honest it should say that this *prevents* 
 * performance degradation.
 *				<[e-mail]>
 * Apparently there're LP64 compilers that generate better
 * code if A-D are declared int. Most notably GCC-x86_64
 * generates better code.
 *				<[e-mail]>
 */
#endif