text: #include "sys-core.h"
  #include "deprecated/sys-md5.h"
  
  
  void MD5_Starts(MD5_CTX *c) {
  	c->A=INIT_DATA_A;
  	c->B=INIT_DATA_B;
  	c->C=INIT_DATA_C;
  	c->D=INIT_DATA_D;
  	c->Nl=0;
  	c->Nh=0;
  	c->num=0;
  }
  
  void MD5_Update(MD5_CTX *c, register unsigned char *data, MD5_LONG len)
  {
  	register ULONG *p;
  	int sw,sc;
  	ULONG l;
  
  	if (len == 0) return;
  
  	l=(c->Nl+(len<<3))&0xffffffffL;
  	/* 95-05-24 eay Fixed a bug with the overflow handling, thanks to
  	 * Wei Dai <weidai@eskimo.com> for pointing it out. */
  	if (l < c->Nl) /* overflow */
  		c->Nh++;
  	c->Nh+=(len>>29);
  	c->Nl=l;
  
  	if (c->num != 0) {
  		p=c->data;
  		sw=c->num>>2;
  		sc=c->num&0x03;
  
  		if ((c->num+len) >= MD5_CBLOCK) {
  			l= p[sw];
  			p_c2l(data,l,sc);
  			p[sw++]=l;
  			for (; sw<MD5_LBLOCK; sw++) {
  				c2l(data,l);
  				p[sw]=l;
  			}
  			len-=(MD5_CBLOCK-c->num);
  
  			md5_block(c,p);
  			c->num=0;
  			/* drop through and do the rest */
  		} else {
  			int ew,ec;
  
  			c->num+=(int)len;
  			if ((sc+len) < 4) { /* ugly, add char's to a word */
  				l= p[sw];
  				p_c2l_p(data,l,sc,len);
  				p[sw]=l;
  			} else {
  				ew=(c->num>>2);
  				ec=(c->num&0x03);
  				l= p[sw];
  				p_c2l(data,l,sc);
  				p[sw++]=l;
  				for (; sw < ew; sw++)
  					{ c2l(data,l); p[sw]=l; }
  				if (ec) {
  					c2l_p(data,l,ec);
  					p[sw]=l;
  				}
  			}
  			return;
  		}
  	}
  	/* we now can process the input data in blocks of MD5_CBLOCK
  	 * chars and save the leftovers to c->data. */
  	p=c->data;
  	while (len >= MD5_CBLOCK) {
  		memcpy(p,data,MD5_CBLOCK);
  		data+=MD5_CBLOCK;
  #ifdef ENDIAN_BIG
  		for (sw=(MD5_LBLOCK/4); sw; sw--) {
  			Endian_Reverse32(p[0]);
  			Endian_Reverse32(p[1]);
  			Endian_Reverse32(p[2]);
  			Endian_Reverse32(p[3]);
  			p+=4;
  		}
  #endif
  		p=c->data;
  		md5_block(c,p);
  		len-=MD5_CBLOCK;
  	}
  	sc=(int)len;
  	c->num=sc;
  	if (sc) {
  		sw=sc>>2;	/* words to copy */
  #ifdef ENDIAN_LITTLE
  		p[sw]=0;
  		memcpy(p,data,sc);
  #else
  		sc&=0x03;
  		for ( ; sw; sw--)
  			{ c2l(data,l); *(p++)=l; }
  		c2l_p(data,l,sc);
  		*p=l;
  #endif
  	}
  }
  
  static void md5_block(MD5_CTX *c, register ULONG *X)
  {
  	register ULONG A,B,C,D;
  
  	A=c->A;
  	B=c->B;
  	C=c->C;
  	D=c->D;
  
  	/* Round 0 */
  	R0(A,B,C,D,X[ 0], 7,0xd76aa478L);
  	R0(D,A,B,C,X[ 1],12,0xe8c7b756L);
  	R0(C,D,A,B,X[ 2],17,0x242070dbL);
  	R0(B,C,D,A,X[ 3],22,0xc1bdceeeL);
  	R0(A,B,C,D,X[ 4], 7,0xf57c0fafL);
  	R0(D,A,B,C,X[ 5],12,0x4787c62aL);
  	R0(C,D,A,B,X[ 6],17,0xa8304613L);
  	R0(B,C,D,A,X[ 7],22,0xfd469501L);
  	R0(A,B,C,D,X[ 8], 7,0x698098d8L);
  	R0(D,A,B,C,X[ 9],12,0x8b44f7afL);
  	R0(C,D,A,B,X[10],17,0xffff5bb1L);
  	R0(B,C,D,A,X[11],22,0x895cd7beL);
  	R0(A,B,C,D,X[12], 7,0x6b901122L);
  	R0(D,A,B,C,X[13],12,0xfd987193L);
  	R0(C,D,A,B,X[14],17,0xa679438eL);
  	R0(B,C,D,A,X[15],22,0x49b40821L);
  	/* Round 1 */
  	R1(A,B,C,D,X[ 1], 5,0xf61e2562L);
  	R1(D,A,B,C,X[ 6], 9,0xc040b340L);
  	R1(C,D,A,B,X[11],14,0x265e5a51L);
  	R1(B,C,D,A,X[ 0],20,0xe9b6c7aaL);
  	R1(A,B,C,D,X[ 5], 5,0xd62f105dL);
  	R1(D,A,B,C,X[10], 9,0x02441453L);
  	R1(C,D,A,B,X[15],14,0xd8a1e681L);
  	R1(B,C,D,A,X[ 4],20,0xe7d3fbc8L);
  	R1(A,B,C,D,X[ 9], 5,0x21e1cde6L);
  	R1(D,A,B,C,X[14], 9,0xc33707d6L);
  	R1(C,D,A,B,X[ 3],14,0xf4d50d87L);
  	R1(B,C,D,A,X[ 8],20,0x455a14edL);
  	R1(A,B,C,D,X[13], 5,0xa9e3e905L);
  	R1(D,A,B,C,X[ 2], 9,0xfcefa3f8L);
  	R1(C,D,A,B,X[ 7],14,0x676f02d9L);
  	R1(B,C,D,A,X[12],20,0x8d2a4c8aL);
  	/* Round 2 */
  	R2(A,B,C,D,X[ 5], 4,0xfffa3942L);
  	R2(D,A,B,C,X[ 8],11,0x8771f681L);
  	R2(C,D,A,B,X[11],16,0x6d9d6122L);
  	R2(B,C,D,A,X[14],23,0xfde5380cL);
  	R2(A,B,C,D,X[ 1], 4,0xa4beea44L);
  	R2(D,A,B,C,X[ 4],11,0x4bdecfa9L);
  	R2(C,D,A,B,X[ 7],16,0xf6bb4b60L);
  	R2(B,C,D,A,X[10],23,0xbebfbc70L);
  	R2(A,B,C,D,X[13], 4,0x289b7ec6L);
  	R2(D,A,B,C,X[ 0],11,0xeaa127faL);
  	R2(C,D,A,B,X[ 3],16,0xd4ef3085L);
  	R2(B,C,D,A,X[ 6],23,0x04881d05L);
  	R2(A,B,C,D,X[ 9], 4,0xd9d4d039L);
  	R2(D,A,B,C,X[12],11,0xe6db99e5L);
  	R2(C,D,A,B,X[15],16,0x1fa27cf8L);
  	R2(B,C,D,A,X[ 2],23,0xc4ac5665L);
  	/* Round 3 */
  	R3(A,B,C,D,X[ 0], 6,0xf4292244L);
  	R3(D,A,B,C,X[ 7],10,0x432aff97L);
  	R3(C,D,A,B,X[14],15,0xab9423a7L);
  	R3(B,C,D,A,X[ 5],21,0xfc93a039L);
  	R3(A,B,C,D,X[12], 6,0x655b59c3L);
  	R3(D,A,B,C,X[ 3],10,0x8f0ccc92L);
  	R3(C,D,A,B,X[10],15,0xffeff47dL);
  	R3(B,C,D,A,X[ 1],21,0x85845dd1L);
  	R3(A,B,C,D,X[ 8], 6,0x6fa87e4fL);
  	R3(D,A,B,C,X[15],10,0xfe2ce6e0L);
  	R3(C,D,A,B,X[ 6],15,0xa3014314L);
  	R3(B,C,D,A,X[13],21,0x4e0811a1L);
  	R3(A,B,C,D,X[ 4], 6,0xf7537e82L);
  	R3(D,A,B,C,X[11],10,0xbd3af235L);
  	R3(C,D,A,B,X[ 2],15,0x2ad7d2bbL);
  	R3(B,C,D,A,X[ 9],21,0xeb86d391L);
  
  	c->A+=A&0xffffffffL;
  	c->B+=B&0xffffffffL;
  	c->C+=C&0xffffffffL;
  	c->D+=D&0xffffffffL;
  }
  
  void MD5_Finish(MD5_CTX *c, unsigned char *md)
  {
  	register int i,j;
  	register ULONG l;
  	register ULONG *p;
  	static unsigned char end[4]={0x80,0x00,0x00,0x00};
  	unsigned char *cp=end;
  
  	/* c->num should definitly have room for at least one more byte. */
  	p=c->data;
  	j=c->num;
  	i=j>>2;
  
  	l=p[i];
  	p_c2l(cp,l,j&0x03);
  	p[i]=l;
  	i++;
  	/* i is the next 'undefined word' */
  	if (c->num >= MD5_LAST_BLOCK) {
  		for (; i<MD5_LBLOCK; i++)
  			p[i]=0;
  		md5_block(c,p);
  		i=0;
  	}
  	for (; i<(MD5_LBLOCK-2); i++)
  		p[i]=0;
  	p[MD5_LBLOCK-2]=c->Nl;
  	p[MD5_LBLOCK-1]=c->Nh;
  	md5_block(c,p);
  	cp=md;
  	l=c->A; l2c(l,cp);
  	l=c->B; l2c(l,cp);
  	l=c->C; l2c(l,cp);
  	l=c->D; l2c(l,cp);
  
  	/* clear stuff, md5_block may be leaving some stuff on the stack
  	 * but I'm not worried :-) */
  	c->num=0;
  	memset((char *)&c,0,sizeof(c)); /* security consideration */
  }
  
  int MD5_CtxSize(void) {
  	return sizeof(MD5_CTX);
  }
  
  unsigned char *MD5(unsigned char *d, MD5_LONG n, unsigned char *md)
  {
  	MD5_CTX c;
  	static unsigned char m[MD5_DIGEST_LENGTH];
  
  	if (!md) md=m;
  	MD5_Starts(&c);
  	MD5_Update(&c,d,n);
  	MD5_Finish(&c, md);
  	//memset(&c,0,sizeof(c)); /* security consideration */
  	return(md);
  }
  
  