-void RC2_encrypt(d,key,encrypt)
-unsigned long *d;
-RC2_KEY *key;
-int encrypt;
- {
- int i,n;
- register RC2_INT *p0,*p1;
- register RC2_INT x0,x1,x2,x3,t;
- unsigned long l;
-
- l=d[0];
- x0=(RC2_INT)l&0xffff;
- x1=(RC2_INT)(l>>16L);
- l=d[1];
- x2=(RC2_INT)l&0xffff;
- x3=(RC2_INT)(l>>16L);
-
- n=3;
- i=5;
- if (encrypt)
- {
- p0=p1= &(key->data[0]);
- for (;;)
- {
- t=(x0+(x1& ~x3)+(x2&x3)+ *(p0++))&0xffff;
- x0=(t<<1)|(t>>15);
- t=(x1+(x2& ~x0)+(x3&x0)+ *(p0++))&0xffff;
- x1=(t<<2)|(t>>14);
- t=(x2+(x3& ~x1)+(x0&x1)+ *(p0++))&0xffff;
- x2=(t<<3)|(t>>13);
- t=(x3+(x0& ~x2)+(x1&x2)+ *(p0++))&0xffff;
- x3=(t<<5)|(t>>11);
-
- if (--i == 0)
- {
- if (--n == 0) break;
- i=(n == 2)?6:5;
-
- x0+=p1[x3&0x3f];
- x1+=p1[x0&0x3f];
- x2+=p1[x1&0x3f];
- x3+=p1[x2&0x3f];
- }
- }
- }
- else
- {
- p0= &(key->data[63]);
- p1= &(key->data[0]);
- for (;;)
- {
- t=((x3<<11)|(x3>>5))&0xffff;
- x3=(t-(x0& ~x2)-(x1&x2)- *(p0--))&0xffff;
- t=((x2<<13)|(x2>>3))&0xffff;
- x2=(t-(x3& ~x1)-(x0&x1)- *(p0--))&0xffff;
- t=((x1<<14)|(x1>>2))&0xffff;
- x1=(t-(x2& ~x0)-(x3&x0)- *(p0--))&0xffff;
- t=((x0<<15)|(x0>>1))&0xffff;
- x0=(t-(x1& ~x3)-(x2&x3)- *(p0--))&0xffff;
-
- if (--i == 0)
- {
- if (--n == 0) break;
- i=(n == 2)?6:5;
-
- x3=(x3-p1[x2&0x3f])&0xffff;
- x2=(x2-p1[x1&0x3f])&0xffff;
- x1=(x1-p1[x0&0x3f])&0xffff;
- x0=(x0-p1[x3&0x3f])&0xffff;
- }
- }
- }
-
- d[0]=(unsigned long)(x0&0xffff)|((unsigned long)(x1&0xffff)<<16L);
- d[1]=(unsigned long)(x2&0xffff)|((unsigned long)(x3&0xffff)<<16L);
- }