engines/e_aep.c: make it BN_ULONG-size and endian "neutral".
[openssl.git] / engines / e_aep.c
index 1953f0643c3aaf68023a166ddd875294bfb40980..1518d2bac1e2126635a4bd0895d029337f4847f1 100644 (file)
@@ -1052,13 +1052,10 @@ static AEP_RV GetBigNumSize(AEP_VOID_PTR ArbBigNum, AEP_U32* BigNumSize)
        /*Cast the ArbBigNum pointer to our BIGNUM struct*/
        bn = (BIGNUM*) ArbBigNum;
 
-#ifdef SIXTY_FOUR_BIT_LONG
-       *BigNumSize = bn->top << 3;
-#else
-       /*Size of the bignum in bytes is equal to the bn->top (no of 32 bit
-         words) multiplies by 4*/
-       *BigNumSize = bn->top << 2;
-#endif
+       *BigNumSize = bn->top*BN_BYTES;
+
+       if (BN_BYTES>sizeof(AEP_U32) && (bn->d[bn->top-1]>>BN_BITS4)==0)
+               *BigNumSize -= 4;
 
        return AEP_R_OK;
        }
@@ -1067,31 +1064,42 @@ static AEP_RV MakeAEPBigNum(AEP_VOID_PTR ArbBigNum, AEP_U32 BigNumSize,
        unsigned char* AEP_BigNum)
        {
        BIGNUM* bn;
-
-#ifndef SIXTY_FOUR_BIT_LONG
-       unsigned char* buf;
-       int i;
-#endif
+       const union { long one; char little; } is_endian = {1};
+       int i,j;
 
        /*Cast the ArbBigNum pointer to our BIGNUM struct*/
        bn = (BIGNUM*) ArbBigNum;
 
-#ifdef SIXTY_FOUR_BIT_LONG
-       memcpy(AEP_BigNum, bn->d, BigNumSize);
-#else
        /*Must copy data into a (monotone) least significant byte first format
          performing endian conversion if necessary*/
-       for(i=0;i<bn->top;i++)
+       if (is_endian.little && sizeof(bn->d[0])==BN_BYTES)
+               memcpy(AEP_BigNum, bn->d, BigNumSize);
+       else
                {
-               buf = (unsigned char*)&bn->d[i];
+               BN_ULONG di;
 
-               *((AEP_U32*)AEP_BigNum) = (AEP_U32)
-                       ((unsigned) buf[1] << 8 | buf[0]) |
-                       ((unsigned) buf[3] << 8 | buf[2])  << 16;
+               for (i=0; BigNumSize>=BN_BYTES; i++)
+                       {
+                       di = bn->d[i];
+                       for (j=0; j<BN_BYTES; j++)
+                               {
+                               AEP_BigNum[j] = (unsigned char)di;
+                               di>>=8;
+                               }
+                       AEP_BigNum += BN_BYTES;
+                       BigNumSize -= BN_BYTES;
+                       }
 
-               AEP_BigNum += 4;
+               if (BigNumSize)
+                       {
+                       di = bn->d[i];
+                       for (j=0; j<BigNumSize; j++)
+                               {
+                               AEP_BigNum[j] = (unsigned char)di;
+                               di>>=8;
+                               }
+                       }
                }
-#endif
 
        return AEP_R_OK;
        }
@@ -1101,36 +1109,46 @@ static AEP_RV ConvertAEPBigNum(void* ArbBigNum, AEP_U32 BigNumSize,
        unsigned char* AEP_BigNum)
        {
        BIGNUM* bn;
-#ifndef SIXTY_FOUR_BIT_LONG
-       int i;
-#endif
+       const union { long one; char little; } is_endian = {1};
+       int i,j,top;
 
        bn = (BIGNUM*)ArbBigNum;
 
        /*Expand the result bn so that it can hold our big num.
          Size is in bits*/
-       bn_expand(bn, (int)(BigNumSize << 3));
+       top = (BigNumSize+BN_BYTES-1)/BN_BYTES;
+       bn_expand(bn, top);
+       bn->top = top;
+       bn->d[top-1] = 0;
 
-#ifdef SIXTY_FOUR_BIT_LONG
-       bn->top = BigNumSize >> 3;
-       
-       if((BigNumSize & 7) != 0)
-               bn->top++;
+       if (is_endian.little && sizeof(bn->d[0])==BN_BYTES)
+               memcpy(bn->d, AEP_BigNum, BigNumSize);
+       else
+               {
+               BN_ULONG di;
 
-       memset(bn->d, 0, bn->top << 3); 
+               for (i=0; BigNumSize>=BN_BYTES; i++)
+                       {
+                       for (di=0,j=BN_BYTES; j!=0; )
+                               {
+                               di <<= 8;
+                               di |= AEP_BigNum[--j];
+                               }
+                       bn->d[i] = di;
+                       AEP_BigNum += BN_BYTES;
+                       BigNumSize -= BN_BYTES;
+                       }
 
-       memcpy(bn->d, AEP_BigNum, BigNumSize);
-#else
-       bn->top = BigNumSize >> 2;
-       for(i=0;i<bn->top;i++)
-               {
-               bn->d[i] = (AEP_U32)
-                       ((unsigned) AEP_BigNum[3] << 8 | AEP_BigNum[2]) << 16 |
-                       ((unsigned) AEP_BigNum[1] << 8 | AEP_BigNum[0]);
-               AEP_BigNum += 4;
+               if (BigNumSize)
+                       {
+                       for (di=0,j=BigNumSize; j!=0; )
+                               {
+                               di <<= 8;
+                               di |= AEP_BigNum[--j];
+                               }
+                       bn->d[i] = di;
+                       }
                }
-#endif
 
        return AEP_R_OK;
 }