config: Abort local/remote block DNS lookups after 30s and warn after 5s.

diff --git a/src/config/config-parser.c b/src/config/config-parser.c
index 7976c49b3a71182bcb073b4632f6bf4c8cea6c90..606e843a45dca21d376d98d78ba5ce4bdd7a2234 100644 (file)
--- a/src/config/config-parser.c
+++ b/src/config/config-parser.c
@@ -19,6 +19,7 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <fcntl.h>
+#include <time.h>
 #ifdef HAVE_GLOB_H
 #  include <glob.h>
 #endif
@@ -27,6 +28,9 @@
 #  define GLOB_BRACE 0
 #endif
 
+#define DNS_LOOKUP_TIMEOUT_SECS 30
+#define DNS_LOOKUP_WARN_SECS 5
+
 static const enum settings_parser_flags settings_parser_flags =
        SETTINGS_PARSER_FLAG_IGNORE_UNKNOWN_KEYS |
        SETTINGS_PARSER_FLAG_TRACK_CHANGES;
@@ -209,6 +213,7 @@ int config_parse_net(const char *value, struct ip_addr *ip_r,
        struct ip_addr *ips;
        const char *p;
        unsigned int ip_count, bits, max_bits;
+       time_t t1, t2;
        int ret;
 
        if (net_parse_range(value, ip_r, bits_r) == 0)
@@ -220,7 +225,11 @@ int config_parse_net(const char *value, struct ip_addr *ip_r,
                p++;
        }
 
+       t1 = time(NULL);
+       alarm(DNS_LOOKUP_TIMEOUT_SECS);
        ret = net_gethostbyname(value, &ips, &ip_count);
+       alarm(0);
+       t2 = time(NULL);
        if (ret != 0) {
                *error_r = t_strdup_printf("gethostbyname(%s) failed: %s",
                                           value, net_gethosterror(ret));
@@ -228,6 +237,11 @@ int config_parse_net(const char *value, struct ip_addr *ip_r,
        }
        *ip_r = ips[0];
 
+       if (t2 - t1 >= DNS_LOOKUP_WARN_SECS) {
+               i_warning("gethostbyname(%s) took %d seconds",
+                         value, (int)(t2-t1));
+       }
+
        max_bits = IPADDR_IS_V4(&ips[0]) ? 32 : 128;
        if (p == NULL || str_to_uint(p, &bits) < 0 || bits > max_bits)
                *bits_r = max_bits;