add support for reverse name lookups from hosts file to getnameinfo

this also affects the legacy gethostbyaddr family, which uses
getnameinfo as its backend.

some other minor changes associated with the refactoring of source
files are also made; in particular, the resolv.conf parser now uses
the same code that's used elsewhere to handle ip literals, so as a
side effect it can now accept a scope id for nameserver addressed with
link-local scope.

1 files changed, 14 insertions, 7 deletions

diff --git a/src/network/res_msend.c b/src/network/res_msend.c
index a5b7793a..5192b4d8 100644
--- a/src/network/res_msend.c
+++ b/src/network/res_msend.c
@@ -12,6 +12,7 @@
 #include <pthread.h>
 #include "stdio_impl.h"
 #include "syscall.h"
+#include "lookup.h"
 
 static void cleanup(void *p)
 {
@@ -47,6 +48,7 @@ int __res_msend(int nqueries, const unsigned char *const *queries,
 	int cs;
 	struct pollfd pfd;
 	unsigned long t0, t1, t2;
+	struct address iplit;
 
 	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
 
@@ -76,13 +78,18 @@ int __res_msend(int nqueries, const unsigned char *const *queries,
 		for (z=s; *z && !isspace(*z); z++);
 		*z=0;
 
-		if (inet_pton(AF_INET, s, &ns[nns].sin.sin_addr)>0) {
-			ns[nns].sin.sin_port = htons(53);
-			ns[nns++].sin.sin_family = AF_INET;
-		} else if (inet_pton(AF_INET6, s, &ns[nns].sin6.sin6_addr)>0) {
-			sl = sizeof sa.sin6;
-			ns[nns].sin6.sin6_port = htons(53);
-			ns[nns++].sin6.sin6_family = family = AF_INET6;
+		if (__lookup_ipliteral(&iplit, s, AF_UNSPEC)>0) {
+			if (iplit.family == AF_INET) {
+				memcpy(&ns[nns].sin.sin_addr, iplit.addr, 4);
+				ns[nns].sin.sin_port = htons(53);
+				ns[nns++].sin.sin_family = AF_INET;
+			} else {
+				sl = sizeof sa.sin6;
+				memcpy(&ns[nns].sin6.sin6_addr, iplit.addr, 16);
+				ns[nns].sin6.sin6_port = htons(53);
+				ns[nns].sin6.sin6_scope_id = iplit.scopeid;
+				ns[nns++].sin6.sin6_family = family = AF_INET6;
+			}
 		}
 	}
 	if (f) __fclose_ca(f);