[crypto/asn1] Fix multiple SCA vulnerabilities during RSA key validation.

[openssl.git] / crypto / asn1 / x_bignum.c

diff --git a/crypto/asn1/x_bignum.c b/crypto/asn1/x_bignum.c
index d7abca6c769835754d6abc334679ef11bd543a85..c5e892900e1665b75bd23a4b6cd8ebf12f15834e 100644 (file)
--- a/crypto/asn1/x_bignum.c
+++ b/crypto/asn1/x_bignum.c
@@ -130,9 +130,20 @@ static int bn_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
 static int bn_secure_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
                          int utype, char *free_cont, const ASN1_ITEM *it)
 {
-    if (!*pval)
-        bn_secure_new(pval, it);
-    return bn_c2i(pval, cont, len, utype, free_cont, it);
+    int ret;
+    BIGNUM *bn;
+
+    if (!*pval && !bn_secure_new(pval, it))
+        return 0;
+
+    ret = bn_c2i(pval, cont, len, utype, free_cont, it);
+    if (!ret)
+        return 0;
+
+    /* Set constant-time flag for all secure BIGNUMS */
+    bn = (BIGNUM *)*pval;
+    BN_set_flags(bn, BN_FLG_CONSTTIME);
+    return ret;
 }
 
 static int bn_print(BIO *out, const ASN1_VALUE **pval, const ASN1_ITEM *it,