summaryrefslogtreecommitdiff
path: root/src/network
diff options
context:
space:
mode:
Diffstat (limited to 'src/network')
-rw-r--r--src/network/getaddrinfo.c39
1 files changed, 39 insertions, 0 deletions
diff --git a/src/network/getaddrinfo.c b/src/network/getaddrinfo.c
index b9439f77..ba26847a 100644
--- a/src/network/getaddrinfo.c
+++ b/src/network/getaddrinfo.c
@@ -3,6 +3,10 @@
#include <netinet/in.h>
#include <netdb.h>
#include <string.h>
+#include <pthread.h>
+#include <unistd.h>
+#include <endian.h>
+#include <errno.h>
#include "lookup.h"
int getaddrinfo(const char *restrict host, const char *restrict serv, const struct addrinfo *restrict hint, struct addrinfo **restrict res)
@@ -43,6 +47,41 @@ int getaddrinfo(const char *restrict host, const char *restrict serv, const stru
}
}
+ if (flags & AI_ADDRCONFIG) {
+ /* Define the "an address is configured" condition for address
+ * families via ability to create a socket for the family plus
+ * routability of the loopback address for the family. */
+ static const struct sockaddr_in lo4 = {
+ .sin_family = AF_INET, .sin_port = 65535,
+ .sin_addr.s_addr = __BYTE_ORDER == __BIG_ENDIAN
+ ? 0x7f000001 : 0x0100007f
+ };
+ static const struct sockaddr_in6 lo6 = {
+ .sin6_family = AF_INET6, .sin6_port = 65535,
+ .sin6_addr = IN6ADDR_LOOPBACK_INIT
+ };
+ int tf[2] = { AF_INET, AF_INET6 };
+ const void *ta[2] = { &lo4, &lo6 };
+ socklen_t tl[2] = { sizeof lo4, sizeof lo6 };
+ for (i=0; i<2; i++) {
+ if (family==tf[1-i]) continue;
+ int s = socket(tf[i], SOCK_CLOEXEC|SOCK_DGRAM,
+ IPPROTO_UDP);
+ if (s>=0) {
+ int cs;
+ pthread_setcancelstate(
+ PTHREAD_CANCEL_DISABLE, &cs);
+ int r = connect(s, ta[i], tl[i]);
+ pthread_setcancelstate(cs, 0);
+ close(s);
+ if (!r) continue;
+ }
+ if (errno != EAFNOSUPPORT) return EAI_SYSTEM;
+ if (family == tf[i]) return EAI_NONAME;
+ family = tf[1-i];
+ }
+ }
+
nservs = __lookup_serv(ports, serv, proto, socktype, flags);
if (nservs < 0) return nservs;