void DES_cfb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
		     long length, DES_key_schedule *schedule, DES_cblock *ivec,
		     int enc)
	{
	register DES_LONG d0,d1,v0,v1;
	register unsigned long l=length;
	register int num=numbits,n=(numbits+7)/8,i;
	DES_LONG ti[2];
	unsigned char *iv;
	unsigned char ovec[16];

	if (num > 64) return;
	iv = &(*ivec)[0];
	c2l(iv,v0);
	c2l(iv,v1);
	if (enc)
		{
		while (l >= (unsigned long)n)
			{
			l-=n;
			ti[0]=v0;
			ti[1]=v1;
			DES_encrypt1((DES_LONG *)ti,schedule,DES_ENCRYPT);
			c2ln(in,d0,d1,n);
			in+=n;
			d0^=ti[0];
			d1^=ti[1];
			l2cn(d0,d1,out,n);
			out+=n;
			/* 30-08-94 - eay - changed because l>>32 and
			 * l<<32 are bad under gcc :-( */
			if (num == 32)
				{ v0=v1; v1=d0; }
			else if (num == 64)
				{ v0=d0; v1=d1; }
			else
				{
				iv=&ovec[0];
				l2c(v0,iv);
				l2c(v1,iv);
				l2c(d0,iv);
				l2c(d1,iv);
				/* shift ovec left most of the bits... */
				memmove(ovec,ovec+num/8,8+(num%8 ? 1 : 0));
				/* now the remaining bits */
				if(num%8 != 0)
					for(i=0 ; i < 8 ; ++i)
						{
						ovec[i]<<=num%8;
						ovec[i]|=ovec[i+1]>>(8-num%8);
						}
				iv=&ovec[0];
				c2l(iv,v0);
				c2l(iv,v1);
				}
			}
		}
	else
		{
		while (l >= (unsigned long)n)
			{
			l-=n;
			ti[0]=v0;
			ti[1]=v1;
			DES_encrypt1((DES_LONG *)ti,schedule,DES_ENCRYPT);
			c2ln(in,d0,d1,n);
			in+=n;
			/* 30-08-94 - eay - changed because l>>32 and
			 * l<<32 are bad under gcc :-( */
			if (num == 32)
				{ v0=v1; v1=d0; }
			else if (num == 64)
				{ v0=d0; v1=d1; }
			else
				{
				iv=&ovec[0];
				l2c(v0,iv);
				l2c(v1,iv);
				l2c(d0,iv);
				l2c(d1,iv);
				/* shift ovec left most of the bits... */
				memmove(ovec,ovec+num/8,8+(num%8 ? 1 : 0));
				/* now the remaining bits */
				if(num%8 != 0)
					for(i=0 ; i < 8 ; ++i)
						{
						ovec[i]<<=num%8;
						ovec[i]|=ovec[i+1]>>(8-num%8);
						}
				iv=&ovec[0];
				c2l(iv,v0);
				c2l(iv,v1);
				}
			d0^=ti[0];
			d1^=ti[1];
			l2cn(d0,d1,out,n);
			out+=n;
			}
		}
	iv = &(*ivec)[0];
	l2c(v0,iv);
	l2c(v1,iv);
	v0=v1=d0=d1=ti[0]=ti[1]=0;
	}