reverted [3945], proper fix for zero value ASN1 integer

2008-05-13 14:15:12 +00:00
parent cb1c54c93e
commit f3884f6da6
1 changed files with 7 additions and 3 deletions
@@ -374,9 +374,13 @@ static bool belongs_to(private_gmp_rsa_private_key_t *this, public_key_t *public
 chunk_t gmp_mpz_to_asn1(const mpz_t value)
 {
 	chunk_t n;
-
-	n.ptr = mpz_export(NULL, &n.len, 1, 1, 1, 0, value);
-
+	
+	n.len = 1 + mpz_sizeinbase(value, 2) / 8;  /* size in bytes */
+	n.ptr = mpz_export(NULL, NULL, 1, n.len, 1, 0, value);
+	if (n.ptr == NULL)
+	{	/* if we have zero in "value", gmp returns NULL */
+		n.len = 0;
+	}
 	return asn1_wrap(ASN1_INTEGER, "m", n);
 }