Bleichenbacher's DSA attack

[oweals/openssl.git] / crypto / bn / bn_mul.c

diff --git a/crypto/bn/bn_mul.c b/crypto/bn/bn_mul.c
index eb5d5256137ea5861f3cf71d2f07ae83b75afbe9..b4c1395549636541264551fae40b10486874d5e4 100644 (file)
--- a/crypto/bn/bn_mul.c
+++ b/crypto/bn/bn_mul.c
@@ -66,6 +66,7 @@
 #include "cryptlib.h"
 #include "bn_lcl.h"
 
+#if defined(NO_ASM) || !defined(__i386) /* Assembler implementation exists only for x86 */
 /* Here follows specialised variants of bn_add_words() and
    bn_sub_words().  They have the property performing operations on
    arrays of different sizes.  The sizes of those arrays is expressed through
@@ -201,6 +202,7 @@ BN_ULONG bn_sub_part_words(BN_ULONG *r,
                }
        return c;
        }
+#endif
 
 BN_ULONG bn_add_part_words(BN_ULONG *r,
        const BN_ULONG *a, const BN_ULONG *b,
@@ -456,7 +458,8 @@ void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
                }
 
 # ifdef BN_MUL_COMBA
-       if (n == 4)
+       if (n == 4 && dna == 0 && dnb == 0) /* XXX: bn_mul_comba4 could take
+                                              extra args to do this well */
                {
                if (!zero)
                        bn_mul_comba4(&(t[n2]),t,&(t[n]));
@@ -466,7 +469,9 @@ void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
                bn_mul_comba4(r,a,b);
                bn_mul_comba4(&(r[n2]),&(a[n]),&(b[n]));
                }
-       else if (n == 8)
+       else if (n == 8 && dna == 0 && dnb == 0) /* XXX: bn_mul_comba8 could
+                                                   take extra args to do this
+                                                   well */
                {
                if (!zero)
                        bn_mul_comba8(&(t[n2]),t,&(t[n]));
@@ -936,8 +941,8 @@ int BN_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx)
        int i;
 #endif
 #ifdef BN_RECURSION
-       BIGNUM *t;
-       int j,k;
+       BIGNUM *t=NULL;
+       int j=0,k;
 #endif
 
 #ifdef BN_COUNT
@@ -1105,7 +1110,13 @@ void bn_mul_normal(BN_ULONG *r, BN_ULONG *a, int na, BN_ULONG *b, int nb)
 
                }
        rr= &(r[na]);
-       rr[0]=bn_mul_words(r,a,na,b[0]);
+       if (nb <= 0)
+               {
+               (void)bn_mul_words(r,a,na,0);
+               return;
+               }
+       else
+               rr[0]=bn_mul_words(r,a,na,b[0]);
 
        for (;;)
                {