BUG/MEDIUM: dns: use the correct server hostname when resolving

The server's host name picked for resolution was incorrect, it did not
skip the address family specifier, did not resolve environment variables,
and messed up with the optional trailing colon.

Instead, let's get the fqdn returned by str2sa_range() and use that
exclusively.

diff --git a/src/server.c b/src/server.c
index 0e5c07999f8d227a75f9805ca2ac4a8028f51a50..f8fbe6a9a11e3bf20cbfe775a4e30367259e2c8f 100644 (file)
--- a/src/server.c
+++ b/src/server.c
@@ -835,6 +835,7 @@ int parse_server(const char *file, int linenum, char **args, struct proxy *curpr
        char *errmsg = NULL;
        int err_code = 0;
        unsigned val;
+       char *fqdn = NULL;
 
        if (!strcmp(args[0], "server") || !strcmp(args[0], "default-server")) {  /* server address */
                int cur_arg;
@@ -904,7 +905,7 @@ int parse_server(const char *file, int linenum, char **args, struct proxy *curpr
                         *  - IP:+N => port=+N, relative
                         *  - IP:-N => port=-N, relative
                         */
-                       sk = str2sa_range(args[2], &port1, &port2, &errmsg, NULL, NULL);
+                       sk = str2sa_range(args[2], &port1, &port2, &errmsg, NULL, &fqdn);
                        if (!sk) {
                                Alert("parsing [%s:%d] : '%s %s' : %s\n", file, linenum, args[0], args[1], errmsg);
                                err_code |= ERR_ALERT | ERR_FATAL;
@@ -936,29 +937,11 @@ int parse_server(const char *file, int linenum, char **args, struct proxy *curpr
                        }
 
                        /* save hostname and create associated name resolution */
-                       switch (sk->ss_family) {
-                       case AF_INET: {
-                               /* remove the port if any */
-                               char *c;
-                               if ((c = rindex(args[2], ':')) != NULL) {
-                                       newsrv->hostname = my_strndup(args[2], c - args[2]);
-                               }
-                               else {
-                                       newsrv->hostname = strdup(args[2]);
-                               }
-                       }
-                               break;
-                       case AF_INET6:
-                               newsrv->hostname = strdup(args[2]);
-                               break;
-                       default:
-                               goto skip_name_resolution;
-                       }
-
-                       /* no name resolution if an IP has been provided */
-                       if (inet_pton(sk->ss_family, newsrv->hostname, trash.str) == 1)
+                       newsrv->hostname = fqdn;
+                       if (!fqdn)
                                goto skip_name_resolution;
 
+                       fqdn = NULL;
                        if ((curr_resolution = calloc(1, sizeof(struct dns_resolution))) == NULL)
                                goto skip_name_resolution;
 
@@ -1779,9 +1762,11 @@ int parse_server(const char *file, int linenum, char **args, struct proxy *curpr
                        srv_lb_commit_status(newsrv);
                }
        }
+       free(fqdn);
        return 0;
 
  out:
+       free(fqdn);
        free(errmsg);
        return err_code;
 }