[Feature] Rework rspamd DNS to use the ordinary upstreams rotation

Issue: #552
Reported by: @Freeaqingme

diff --git a/src/libserver/dns.c b/src/libserver/dns.c
index 3c67411a0ad13c8555f7b5a2e5c089fd17800820..eb0e4e9a292dc2c7364ea2f3d5e7342c30249afb 100644 (file)
--- a/src/libserver/dns.c
+++ b/src/libserver/dns.c
@@ -21,6 +21,24 @@
 #include "uthash.h"
 #include "rdns_event.h"
 
+static struct rdns_upstream_elt* rspamd_dns_select_upstream (const char *name,
+               size_t len, void *ups_data);
+static struct rdns_upstream_elt* rspamd_dns_select_upstream_retransmit (
+               const char *name,
+               size_t len, void *ups_data);
+static void rspamd_dns_upstream_ok (struct rdns_upstream_elt *elt,
+               void *ups_data);
+static void rspamd_dns_upstream_fail (struct rdns_upstream_elt *elt,
+               void *ups_data);
+
+static struct rdns_upstream_context rspamd_ups_ctx = {
+               .select = rspamd_dns_select_upstream,
+               .select_retransmit = rspamd_dns_select_upstream_retransmit,
+               .ok = rspamd_dns_upstream_ok,
+               .fail = rspamd_dns_upstream_fail,
+               .data = NULL
+};
+
 struct rspamd_dns_request_ud {
        struct rspamd_async_session *session;
        dns_callback_type cb;
@@ -176,78 +194,147 @@ static void rspamd_rnds_log_bridge (
                        function, format, args);
 }
 
+static void
+rspamd_dns_server_init (struct upstream *up, gpointer ud)
+{
+       struct rspamd_dns_resolver *r = ud;
+       rspamd_inet_addr_t *addr;
+       void *serv;
+       struct rdns_upstream_elt *elt;
+
+       addr = rspamd_upstream_addr (up);
+
+       if (r->cfg) {
+               serv = rdns_resolver_add_server (r->r, rspamd_inet_address_to_string (addr),
+                               rspamd_inet_address_get_port (addr), 0, r->cfg->dns_io_per_server);
+       }
+       else {
+               serv = rdns_resolver_add_server (r->r, rspamd_inet_address_to_string (addr),
+                               rspamd_inet_address_get_port (addr), 0, 8);
+       }
+
+       elt = g_slice_alloc0 (sizeof (*elt));
+       elt->server = serv;
+       elt->lib_data = up;
+
+       rspamd_upstream_set_data (up, elt);
+}
+
 struct rspamd_dns_resolver *
 dns_resolver_init (rspamd_logger_t *logger,
        struct event_base *ev_base,
        struct rspamd_config *cfg)
 {
-       GList *cur;
-       struct rspamd_dns_resolver *new;
-       gchar *begin, *p, *err;
-       gint priority;
+       struct rspamd_dns_resolver *dns_resolver;
 
-       new = g_slice_alloc0 (sizeof (struct rspamd_dns_resolver));
-       new->ev_base = ev_base;
+       dns_resolver = g_slice_alloc0 (sizeof (struct rspamd_dns_resolver));
+       dns_resolver->ev_base = ev_base;
        if (cfg != NULL) {
-               new->request_timeout = cfg->dns_timeout;
-               new->max_retransmits = cfg->dns_retransmits;
+               dns_resolver->request_timeout = cfg->dns_timeout;
+               dns_resolver->max_retransmits = cfg->dns_retransmits;
        }
        else {
-               new->request_timeout = 1;
-               new->max_retransmits = 2;
+               dns_resolver->request_timeout = 1;
+               dns_resolver->max_retransmits = 2;
        }
 
-       new->r = rdns_resolver_new ();
-       rdns_bind_libevent (new->r, new->ev_base);
+       dns_resolver->r = rdns_resolver_new ();
+       rdns_bind_libevent (dns_resolver->r, dns_resolver->ev_base);
 
        if (cfg != NULL) {
-               rdns_resolver_set_log_level (new->r, cfg->log_level);
+               rdns_resolver_set_log_level (dns_resolver->r, cfg->log_level);
+               dns_resolver->cfg = cfg;
        }
 
-       rdns_resolver_set_logger (new->r, rspamd_rnds_log_bridge, logger);
+       rdns_resolver_set_logger (dns_resolver->r, rspamd_rnds_log_bridge, logger);
 
        if (cfg == NULL || cfg->nameservers == NULL) {
                /* Parse resolv.conf */
-               if (!rdns_resolver_parse_resolv_conf (new->r, "/etc/resolv.conf")) {
+               if (!rdns_resolver_parse_resolv_conf (dns_resolver->r, "/etc/resolv.conf")) {
                        msg_err_config (
                                "cannot parse resolv.conf and no nameservers defined, so no ways to resolve addresses");
-                       rdns_resolver_release (new->r);
-                       new->r = NULL;
+                       rdns_resolver_release (dns_resolver->r);
+                       dns_resolver->r = NULL;
 
-                       return new;
+                       return dns_resolver;
                }
        }
        else {
-               cur = cfg->nameservers;
-               while (cur) {
-                       begin = cur->data;
-                       p = strchr (begin, ':');
-                       if (p != NULL) {
-                               *p = '\0';
-                               p++;
-                               priority = strtoul (p, &err, 10);
-                               if (err != NULL && *err != '\0') {
-                                       msg_info_config (
-                                               "bad character '%xc', must be 'm' or 's' or a numeric priority",
-                                               *err);
-                               }
-                       }
-                       else {
-                               priority = 0;
-                       }
-                       if (!rdns_resolver_add_server (new->r, begin, 53, priority,
-                               cfg->dns_io_per_server)) {
-                               msg_warn_config ("cannot parse ip address of nameserver: %s", begin);
-                               cur = g_list_next (cur);
-                               continue;
-                       }
-
-                       cur = g_list_next (cur);
+               dns_resolver->ups = rspamd_upstreams_create (cfg->ups_ctx);
+
+               if (!rspamd_upstreams_from_ucl (dns_resolver->ups, cfg->nameservers,
+                               53, dns_resolver)) {
+                       msg_err_config ("cannot parse DNS nameservers definitions");
+                       rdns_resolver_release (dns_resolver->r);
+                       dns_resolver->r = NULL;
+
+                       return dns_resolver;
                }
 
+               rspamd_upstreams_foreach (dns_resolver->ups, rspamd_dns_server_init,
+                               dns_resolver);
+               rspamd_upstreams_set_flags (dns_resolver->ups, RSPAMD_UPSTREAM_FLAG_NORESOLVE);
+               rdns_resolver_set_upstream_lib (dns_resolver->r, &rspamd_ups_ctx,
+                               dns_resolver->ups);
+       }
+
+       rdns_resolver_init (dns_resolver->r);
+
+       return dns_resolver;
+}
+
+
+static struct rdns_upstream_elt*
+rspamd_dns_select_upstream (const char *name,
+               size_t len, void *ups_data)
+{
+       struct upstream_list *ups = ups_data;
+       struct upstream *up;
+
+       up = rspamd_upstream_get (ups, RSPAMD_UPSTREAM_ROUND_ROBIN, name, len);
+
+       if (up) {
+               msg_debug ("select %s", rspamd_upstream_name (up));
+
+               return rspamd_upstream_get_data (up);
        }
 
-       rdns_resolver_init (new->r);
+       return NULL;
+}
+
+static struct rdns_upstream_elt*
+rspamd_dns_select_upstream_retransmit (
+               const char *name,
+               size_t len, void *ups_data)
+{
+       struct upstream_list *ups = ups_data;
+       struct upstream *up;
+
+       up = rspamd_upstream_get_forced (ups, RSPAMD_UPSTREAM_RANDOM, name, len);
+
+       if (up) {
+               msg_debug ("select forced %s", rspamd_upstream_name (up));
+
+               return rspamd_upstream_get_data (up);
+       }
+
+       return NULL;
+}
+
+static void
+rspamd_dns_upstream_ok (struct rdns_upstream_elt *elt,
+               void *ups_data)
+{
+       struct upstream *up = elt->lib_data;
+
+       rspamd_upstream_ok (up);
+}
+
+static void
+rspamd_dns_upstream_fail (struct rdns_upstream_elt *elt,
+               void *ups_data)
+{
+       struct upstream *up = elt->lib_data;
 
-       return new;
+       rspamd_upstream_fail (up);
 }

diff --git a/src/libserver/dns.h b/src/libserver/dns.h
index e465de82dd37728374f23984e5ad3a6d6e160040..52325af918cd6d23dc1003de8ad38942863459b1 100644 (file)
--- a/src/libserver/dns.h
+++ b/src/libserver/dns.h
@@ -22,10 +22,15 @@
 #include "events.h"
 #include "logger.h"
 #include "rdns.h"
+#include "upstream.h"
+
+struct rspamd_config;
 
 struct rspamd_dns_resolver {
        struct rdns_resolver *r;
        struct event_base *ev_base;
+       struct upstream_list *ups;
+       struct rspamd_config *cfg;
        gdouble request_timeout;
        guint max_retransmits;
 };