Put the first stage of my bignum debugging adventures into CVS. This code

is itself experimental, and in addition may cause execution to break on
existing openssl "bugs" that previously were harmless or at least
invisible.

1 files changed, 17 insertions, 4 deletions

diff --git a/crypto/bn/bn_lib.c b/crypto/bn/bn_lib.c
index f63232b..85b72e0 100644
--- a/crypto/bn/bn_lib.c
+++ b/crypto/bn/bn_lib.c
@@ -286,6 +286,7 @@ void BN_free(BIGNUM *a)
 void BN_init(BIGNUM *a)
 	{
 	memset(a,0,sizeof(BIGNUM));
+	bn_check_top(a);
 	}
 
 BIGNUM *BN_new(void)
@@ -302,6 +303,7 @@ BIGNUM *BN_new(void)
 	ret->neg=0;
 	ret->dmax=0;
 	ret->d=NULL;
+	bn_check_top(ret);
 	return(ret);
 	}
 
@@ -420,6 +422,7 @@ BIGNUM *bn_dup_expand(const BIGNUM *b, int words)
 		r = BN_dup(b);
 		}
 
+	bn_check_top(r);
 	return r;
 	}
 
@@ -462,6 +465,7 @@ BIGNUM *bn_expand2(BIGNUM *b, int words)
 			A[0]=0;
 		assert(A == &(b->d[b->dmax]));
 		}
+	else if(b) bn_check_top(b);
 	return b;
 	}
 
@@ -479,6 +483,7 @@ BIGNUM *BN_dup(const BIGNUM *a)
 	/* now  r == t || r == NULL */
 	if (r == NULL)
 		BN_free(t);
+	bn_check_top(r);
 	return r;
 	}
 
@@ -518,6 +523,7 @@ BIGNUM *BN_copy(BIGNUM *a, const BIGNUM *b)
 	if ((a->top == 0) && (a->d != NULL))
 		a->d[0]=0;
 	a->neg=b->neg;
+	bn_check_top(a);
 	return(a);
 	}
 
@@ -561,8 +567,9 @@ BIGNUM *BN_ncopy(BIGNUM *a, const BIGNUM *b, size_t n)
 	a->top = min;
 
 	a->neg = b->neg;
-	bn_fix_top(a);
+	bn_correct_top(a);
 
+	bn_check_top(a);
 	return(a);
 	}
 
@@ -592,6 +599,8 @@ void BN_swap(BIGNUM *a, BIGNUM *b)
 	
 	a->flags = (flags_old_a & BN_FLG_MALLOCED) | (flags_old_b & BN_FLG_STATIC_DATA);
 	b->flags = (flags_old_b & BN_FLG_MALLOCED) | (flags_old_a & BN_FLG_STATIC_DATA);
+	bn_check_top(a);
+	bn_check_top(b);
 	}
 
 
@@ -601,6 +610,7 @@ void BN_clear(BIGNUM *a)
 		memset(a->d,0,a->dmax*sizeof(a->d[0]));
 	a->top=0;
 	a->neg=0;
+	bn_check_top(a);
 	}
 
 BN_ULONG BN_get_word(const BIGNUM *a)
@@ -648,6 +658,7 @@ int BN_set_word(BIGNUM *a, BN_ULONG w)
 		a->d[i]=(BN_ULONG)w&BN_MASK2;
 		if (a->d[i] != 0) a->top=i+1;
 		}
+	bn_check_top(a);
 	return(1);
 	}
 
@@ -684,7 +695,7 @@ BIGNUM *BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret)
 		}
 	/* need to call this due to clear byte at top if avoiding
 	 * having the top bit set (-ve number) */
-	bn_fix_top(ret);
+	bn_correct_top(ret);
 	return(ret);
 	}
 
@@ -700,6 +711,7 @@ int BN_bn2bin(const BIGNUM *a, unsigned char *to)
 		l=a->d[i/BN_BYTES];
 		*(to++)=(unsigned char)(l>>(8*(i%BN_BYTES)))&0xff;
 		}
+	bn_check_top(a);
 	return(n);
 	}
 
@@ -781,6 +793,7 @@ int BN_set_bit(BIGNUM *a, int n)
 		}
 
 	a->d[i]|=(((BN_ULONG)1)<<j);
+	bn_check_top(a);
 	return(1);
 	}
 
@@ -793,7 +806,7 @@ int BN_clear_bit(BIGNUM *a, int n)
 	if (a->top <= i) return(0);
 
 	a->d[i]&=(~(((BN_ULONG)1)<<j));
-	bn_fix_top(a);
+	bn_correct_top(a);
 	return(1);
 	}
 
@@ -822,7 +835,7 @@ int BN_mask_bits(BIGNUM *a, int n)
 		a->top=w+1;
 		a->d[w]&= ~(BN_MASK2<<b);
 		}
-	bn_fix_top(a);
+	bn_correct_top(a);
 	return(1);
 	}