[Minor] Spf: Deal with enormously large SPF records

diff --git a/src/libserver/spf.c b/src/libserver/spf.c
index a506d73df50d14ff2b42e350149535bcaa1a7ed8..dd85dfbe57ff8c2b0544da6e806855594be50e44 100644 (file)
--- a/src/libserver/spf.c
+++ b/src/libserver/spf.c
@@ -847,15 +847,24 @@ spf_record_dns_callback (struct rdns_reply *reply, gpointer arg)
        struct spf_addr *addr;
        struct spf_record *rec;
        const struct rdns_request_name *req_name;
+       bool truncated = false;
 
        rec = cb->rec;
        task = rec->task;
 
        cb->rec->requests_inflight--;
        addr = cb->addr;
+       req_name = rdns_request_get_name (reply->request, NULL);
 
-       if (reply->code == RDNS_RC_NOERROR) {
-               req_name = rdns_request_get_name (reply->request, NULL);
+       if (reply->flags & RDNS_TRUNCATED) {
+               /* Do not process truncated DNS replies */
+               truncated = true;
+               msg_warn_spf ("got a truncated record when trying to resolve %s (%s type) for SPF domain %s",
+                               req_name, rdns_str_from_type (req_name->type),
+                               rec->sender_domain);
+       }
+
+       if (reply->code == RDNS_RC_NOERROR && !truncated) {
 
                LL_FOREACH (reply->entries, elt_data) {
                        /* Adjust ttl if a resolved record has lower ttl than spf record itself */
@@ -2434,26 +2443,40 @@ spf_dns_callback (struct rdns_reply *reply, gpointer arg)
 
        rec->requests_inflight--;
 
-       if (reply->code == RDNS_RC_NOERROR) {
-               resolved = rspamd_spf_new_addr_list (rec, rec->sender_domain);
-               if (rec->resolved->len == 1) {
-                       /* Top level resolved element */
-                       rec->ttl = reply->entries->ttl;
-               }
-       }
-       else if ((reply->code == RDNS_RC_NOREC || reply->code == RDNS_RC_NXDOMAIN)
-                       && rec->dns_requests == 0) {
-               resolved = rspamd_spf_new_addr_list (rec, rec->sender_domain);
-               addr = g_malloc0 (sizeof(*addr));
-               addr->flags |= RSPAMD_SPF_FLAG_NA;
-               g_ptr_array_insert (resolved->elts, 0, addr);
-       }
-       else if (reply->code != RDNS_RC_NOREC && reply->code != RDNS_RC_NXDOMAIN
-                       && rec->dns_requests == 0) {
-               resolved = rspamd_spf_new_addr_list (rec, rec->sender_domain);
-               addr = g_malloc0 (sizeof(*addr));
+       if (reply->flags & RDNS_TRUNCATED) {
+               msg_warn_spf ("got a truncated record when trying to resolve TXT record for %s",
+                               rec->sender_domain);
+               resolved = rspamd_spf_new_addr_list(rec, rec->sender_domain);
+               addr = g_malloc0(sizeof(*addr));
                addr->flags |= RSPAMD_SPF_FLAG_TEMPFAIL;
-               g_ptr_array_insert (resolved->elts, 0, addr);
+               g_ptr_array_insert(resolved->elts, 0, addr);
+
+               rspamd_spf_maybe_return (rec);
+
+               return;
+       }
+       else {
+               if (reply->code == RDNS_RC_NOERROR) {
+                       resolved = rspamd_spf_new_addr_list(rec, rec->sender_domain);
+                       if (rec->resolved->len == 1) {
+                               /* Top level resolved element */
+                               rec->ttl = reply->entries->ttl;
+                       }
+               }
+               else if ((reply->code == RDNS_RC_NOREC || reply->code == RDNS_RC_NXDOMAIN)
+                                && rec->dns_requests == 0) {
+                       resolved = rspamd_spf_new_addr_list(rec, rec->sender_domain);
+                       addr = g_malloc0(sizeof(*addr));
+                       addr->flags |= RSPAMD_SPF_FLAG_NA;
+                       g_ptr_array_insert(resolved->elts, 0, addr);
+               }
+               else if (reply->code != RDNS_RC_NOREC && reply->code != RDNS_RC_NXDOMAIN
+                                && rec->dns_requests == 0) {
+                       resolved = rspamd_spf_new_addr_list(rec, rec->sender_domain);
+                       addr = g_malloc0(sizeof(*addr));
+                       addr->flags |= RSPAMD_SPF_FLAG_TEMPFAIL;
+                       g_ptr_array_insert(resolved->elts, 0, addr);
+               }
        }
 
        if (resolved) {