slirp: use localhost as dns when /etc/resolv.conf empty
diff --git a/src/slirp.c b/src/slirp.c
index 57d0768..f26c987 100644
--- a/src/slirp.c
+++ b/src/slirp.c
@@ -389,6 +389,48 @@
return 1;
}
+static bool try_and_setdns_server(int af, unsigned found, unsigned if_index,
+ const char *buff2, void *pdns_addr, void *cached_addr,
+ socklen_t addrlen, uint32_t *scope_id, uint32_t *cached_scope_id,
+ unsigned *cached_time)
+{
+ union {
+ struct in_addr dns_addr;
+ struct in6_addr dns6_addr;
+ } tmp_addr;
+
+ assert(sizeof(tmp_addr) >= addrlen);
+
+ if (!inet_pton(af, buff2, &tmp_addr))
+ return false;
+
+ /* If it's the first one, set it to dns_addr */
+ if (!found) {
+ memcpy(pdns_addr, &tmp_addr, addrlen);
+ memcpy(cached_addr, &tmp_addr, addrlen);
+ if (scope_id) {
+ *scope_id = if_index;
+ }
+ if (cached_scope_id) {
+ *cached_scope_id = if_index;
+ }
+ *cached_time = curtime;
+ }
+
+ if (found > 2) {
+ DEBUG_MISC(" (more)");
+ } else if (slirp_debug & DBG_MISC) {
+ char s[INET6_ADDRSTRLEN];
+ const char *res = inet_ntop(af, &tmp_addr, s, sizeof(s));
+ if (!res) {
+ res = " (string conversion error)";
+ }
+ DEBUG_MISC(" %s", res);
+ }
+
+ return true;
+}
+
static int get_dns_addr_resolv_conf(int af, void *pdns_addr, void *cached_addr,
socklen_t addrlen,
uint32_t *scope_id, uint32_t *cached_scope_id,
@@ -398,13 +440,9 @@
char buff2[257];
FILE *f;
int found = 0;
- union {
- struct in_addr dns_addr;
- struct in6_addr dns6_addr;
- } tmp_addr;
unsigned if_index;
+ unsigned nameservers = 0;
- assert(sizeof(tmp_addr) >= addrlen);
f = fopen(RESOLV_CONF_PATH, "r");
if (!f)
return -1;
@@ -420,39 +458,30 @@
if_index = 0;
}
- if (!inet_pton(af, buff2, &tmp_addr)) {
- continue;
- }
- /* If it's the first one, set it to dns_addr */
- if (!found) {
- memcpy(pdns_addr, &tmp_addr, addrlen);
- memcpy(cached_addr, &tmp_addr, addrlen);
- if (scope_id) {
- *scope_id = if_index;
- }
- if (cached_scope_id) {
- *cached_scope_id = if_index;
- }
- *cached_time = curtime;
- }
+ nameservers++;
- if (++found > 3) {
- DEBUG_MISC(" (more)");
- break;
- } else if (slirp_debug & DBG_MISC) {
- char s[INET6_ADDRSTRLEN];
- const char *res = inet_ntop(af, &tmp_addr, s, sizeof(s));
- if (!res) {
- res = " (string conversion error)";
- }
- DEBUG_MISC(" %s", res);
- }
+ if (!try_and_setdns_server(af, found, if_index, buff2, pdns_addr,
+ cached_addr, addrlen, scope_id,
+ cached_scope_id, cached_time))
+ continue;
+
+ if (++found > 3)
+ break;
}
}
fclose(f);
- if (!found)
+ if (nameservers && !found)
return -1;
- return 0;
+ if (!nameservers) {
+ found += try_and_setdns_server(af, found, 0, "127.0.0.1",
+ pdns_addr, cached_addr, addrlen, scope_id,
+ cached_scope_id, cached_time);
+ found += try_and_setdns_server(af, found, 0, "::1",
+ pdns_addr, cached_addr, addrlen, scope_id,
+ cached_scope_id, cached_time);
+ }
+
+ return found ? 0 : -1;
}
int get_dns_addr(struct in_addr *pdns_addr)
