/*
* If it's not explicitly trusted then check if there is an alternative
* chain that could be used. We only do this if we haven't already
- * checked via TRUSTED_FIRST
+ * checked via TRUSTED_FIRST and the user hasn't switched off alternate
+ * chain checking
*/
retry = 0;
if (i != X509_TRUST_TRUSTED
- && !(ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)) {
+ && !(ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
+ && !(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS)) {
while (j-- > 1) {
xtmp2 = sk_X509_value(ctx->chain, j - 1);
ok = ctx->get_issuer(&xtmp, ctx, xtmp2);
/* Allow partial chains if at least one certificate is in trusted store */
# define X509_V_FLAG_PARTIAL_CHAIN 0x80000
+/*
+ * If the initial chain is not trusted, do not attempt to build an alternative
+ * chain. Alternate chain checking was introduced in 1.0.2b. Setting this flag
+ * will force the behaviour to match that of previous versions.
+ */
+# define X509_V_FLAG_NO_ALT_CHAINS 0x100000
# define X509_VP_FLAG_DEFAULT 0x1
# define X509_VP_FLAG_OVERWRITE 0x2