minor signed/unsigned warning fixes

[openssl.git] / crypto / des / cfb_enc.c

diff --git a/crypto/des/cfb_enc.c b/crypto/des/cfb_enc.c
index 136efba95b5f85d0dfa92310f274b08a3fdb9a81..0013556c78d748b5f54ebadc62b890b4262c03ad 100644 (file)
--- a/crypto/des/cfb_enc.c
+++ b/crypto/des/cfb_enc.c
@@ -65,38 +65,26 @@
  * the second.  The second 12 bits will come from the 3rd and half the 4th
  * byte.
  */
+/* Until Aug 1 2003 this function did not correctly implement CFB-r, so it
+ * will not be compatible with any encryption prior to that date. Ben. */
 void DES_cfb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
-                    long length, DES_key_schedule *schedule, DES_cblock *ivec, int enc)
+                    long length, DES_key_schedule *schedule, DES_cblock *ivec,
+                    int enc)
        {
-       register DES_LONG d0,d1,v0,v1,n=(numbits+7)/8;
-       register DES_LONG mask0,mask1;
+       register DES_LONG d0,d1,v0,v1;
        register unsigned long l=length;
-       register int num=numbits;
+       register int num=numbits,n=(numbits+7)/8,i;
        DES_LONG ti[2];
        unsigned char *iv;
+       unsigned char ovec[16];
 
        if (num > 64) return;
-       if (num > 32)
-               {
-               mask0=0xffffffffL;
-               if (num == 64)
-                       mask1=mask0;
-               else    mask1=(1L<<(num-32))-1;
-               }
-       else
-               {
-               if (num == 32)
-                       mask0=0xffffffffL;
-               else    mask0=(1L<<num)-1;
-               mask1=0x00000000L;
-               }
-
        iv = &(*ivec)[0];
        c2l(iv,v0);
        c2l(iv,v1);
        if (enc)
                {
-               while (l >= n)
+               while (l >= (unsigned long)n)
                        {
                        l-=n;
                        ti[0]=v0;
@@ -104,8 +92,8 @@ void DES_cfb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
                        DES_encrypt1((DES_LONG *)ti,schedule,DES_ENCRYPT);
                        c2ln(in,d0,d1,n);
                        in+=n;
-                       d0=(d0^ti[0])&mask0;
-                       d1=(d1^ti[1])&mask1;
+                       d0^=ti[0];
+                       d1^=ti[1];
                        l2cn(d0,d1,out,n);
                        out+=n;
                        /* 30-08-94 - eay - changed because l>>32 and
@@ -114,21 +102,31 @@ void DES_cfb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
                                { v0=v1; v1=d0; }
                        else if (num == 64)
                                { v0=d0; v1=d1; }
-                       else if (num > 32) /* && num != 64 */
-                               {
-                               v0=((v1>>(num-32))|(d0<<(64-num)))&0xffffffffL;
-                               v1=((d0>>(num-32))|(d1<<(64-num)))&0xffffffffL;
-                               }
-                       else /* num < 32 */
+                       else
                                {
-                               v0=((v0>>num)|(v1<<(32-num)))&0xffffffffL;
-                               v1=((v1>>num)|(d0<<(32-num)))&0xffffffffL;
+                               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 >= n)
+               while (l >= (unsigned long)n)
                        {
                        l-=n;
                        ti[0]=v0;
@@ -142,18 +140,28 @@ void DES_cfb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
                                { v0=v1; v1=d0; }
                        else if (num == 64)
                                { v0=d0; v1=d1; }
-                       else if (num > 32) /* && num != 64 */
-                               {
-                               v0=((v1>>(num-32))|(d0<<(64-num)))&0xffffffffL;
-                               v1=((d0>>(num-32))|(d1<<(64-num)))&0xffffffffL;
-                               }
-                       else /* num < 32 */
+                       else
                                {
-                               v0=((v0>>num)|(v1<<(32-num)))&0xffffffffL;
-                               v1=((v1>>num)|(d0<<(32-num)))&0xffffffffL;
+                               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=(d0^ti[0])&mask0;
-                       d1=(d1^ti[1])&mask1;
+                       d0^=ti[0];
+                       d1^=ti[1];
                        l2cn(d0,d1,out,n);
                        out+=n;
                        }