From: Vincent Bernat <vincent@bernat.im>
Date: Wed, 28 Jan 2015 13:55:31 +0000 (+0100)
Subject: priv: replace the use of `gethostbyname()` by `getaddrinfo()`
X-Git-Tag: 0.7.14~43
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=65e5293aeedfca68c4fd1f7f1bf22d43ca65e2ad;p=thirdparty%2Flldpd.git

priv: replace the use of `gethostbyname()` by `getaddrinfo()`

`gethostbyname()` was uses to get the canonical name. `getaddrinfo()`
should work even if there is no IPv4 at all in the system.
---

diff --git a/src/daemon/priv.c b/src/daemon/priv.c
index f660bafd..0d9ea4a2 100644
--- a/src/daemon/priv.c
+++ b/src/daemon/priv.c
@@ -35,7 +35,6 @@
 #include <grp.h>
 #include <sys/utsname.h>
 #include <sys/ioctl.h>
-#include <netdb.h>
 #include <netinet/if_ether.h>
 
 #if defined HOST_OS_FREEBSD || HOST_OS_OSX || HOST_OS_DRAGONFLY
@@ -216,11 +215,14 @@ static void
 asroot_gethostname()
 {
 	struct utsname un;
-	struct hostent *hp;
+	struct addrinfo hints = {
+		.ai_flags = AI_CANONNAME
+	};
+	struct addrinfo *res;
 	int len;
 	if (uname(&un) < 0)
 		fatal("privsep", "failed to get system information");
-	if ((hp = gethostbyname(un.nodename)) == NULL) {
+	if (getaddrinfo(un.nodename, NULL, &hints, &res) != 0) {
 		log_info("privsep", "unable to get system name");
 #ifdef HAVE_RES_INIT
 		res_init();
@@ -229,9 +231,10 @@ asroot_gethostname()
                 must_write(PRIV_PRIVILEGED, &len, sizeof(int));
                 must_write(PRIV_PRIVILEGED, un.nodename, len + 1);
         } else {
-                len = strlen(hp->h_name);
+                len = strlen(res->ai_canonname);
                 must_write(PRIV_PRIVILEGED, &len, sizeof(int));
-                must_write(PRIV_PRIVILEGED, hp->h_name, len + 1);
+                must_write(PRIV_PRIVILEGED, res->ai_canonname, len + 1);
+		freeaddrinfo(res);
         }
 }