This is essentially Intel 32-bit compiler tune-up. To start with all
[openssl.git] / crypto / des / cfb_enc.c
index 0013556..6738e7c 100644 (file)
@@ -58,6 +58,7 @@
 
 #include "e_os.h"
 #include "des_locl.h"
+#include <assert.h>
 
 /* The input and output are loaded in multiples of 8 bits.
  * What this means is that if you hame numbits=12 and length=2
@@ -73,12 +74,22 @@ void DES_cfb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
        {
        register DES_LONG d0,d1,v0,v1;
        register unsigned long l=length;
-       register int num=numbits,n=(numbits+7)/8,i;
+       register int num=numbits/8,n=(numbits+7)/8,i,rem=numbits%8;
        DES_LONG ti[2];
        unsigned char *iv;
+#ifndef L_ENDIAN
        unsigned char ovec[16];
+#else
+       unsigned int  sh[4];
+       unsigned char *ovec=(unsigned char *)sh;
 
-       if (num > 64) return;
+       /* I kind of count that compiler optimizes away this assertioni,*/
+       assert (sizeof(sh[0])==4);      /* as this holds true for all,  */
+                                       /* but 16-bit platforms...      */
+                                       
+#endif
+
+       if (numbits<=0 || numbits > 64) return;
        iv = &(*ivec)[0];
        c2l(iv,v0);
        c2l(iv,v1);
@@ -98,29 +109,34 @@ void DES_cfb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
                        out+=n;
                        /* 30-08-94 - eay - changed because l>>32 and
                         * l<<32 are bad under gcc :-( */
-                       if (num == 32)
+                       if (numbits == 32)
                                { v0=v1; v1=d0; }
-                       else if (num == 64)
+                       else if (numbits == 64)
                                { v0=d0; v1=d1; }
                        else
                                {
+#ifndef L_ENDIAN
                                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)
+#else
+                               sh[0]=v0, sh[1]=v1, sh[2]=d0, sh[3]=d1;
+#endif
+                               if (rem==0)
+                                       memcpy(ovec,ovec+num,8);
+                               else
                                        for(i=0 ; i < 8 ; ++i)
-                                               {
-                                               ovec[i]<<=num%8;
-                                               ovec[i]|=ovec[i+1]>>(8-num%8);
-                                               }
+                                               ovec[i]=ovec[i+num]<<rem |
+                                                       ovec[i+num+1]>>(8-rem);
+#ifdef L_ENDIAN
+                               v0=sh[0], v1=sh[1];
+#else
                                iv=&ovec[0];
                                c2l(iv,v0);
                                c2l(iv,v1);
+#endif
                                }
                        }
                }
@@ -136,29 +152,34 @@ void DES_cfb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
                        in+=n;
                        /* 30-08-94 - eay - changed because l>>32 and
                         * l<<32 are bad under gcc :-( */
-                       if (num == 32)
+                       if (numbits == 32)
                                { v0=v1; v1=d0; }
-                       else if (num == 64)
+                       else if (numbits == 64)
                                { v0=d0; v1=d1; }
                        else
                                {
+#ifndef L_ENDIAN
                                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)
+#else
+                               sh[0]=v0, sh[1]=v1, sh[2]=d0, sh[3]=d1;
+#endif
+                               if (rem==0)
+                                       memcpy (ovec,ovec+num,8);
+                               else
                                        for(i=0 ; i < 8 ; ++i)
-                                               {
-                                               ovec[i]<<=num%8;
-                                               ovec[i]|=ovec[i+1]>>(8-num%8);
-                                               }
+                                               ovec[i]=ovec[i+num]<<rem |
+                                                       ovec[i+num+1]>>(8-rem);
+#ifdef L_ENDIAN
+                               v0=sh[0], v1=sh[1];
+#else
                                iv=&ovec[0];
                                c2l(iv,v0);
                                c2l(iv,v1);
+#endif
                                }
                        d0^=ti[0];
                        d1^=ti[1];