X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fnetwork%2F__dns.c;h=97d8031ca1d50e110d30e12575c2957bca5e682f;hb=6739b13a172aad9c01572c04cadacc99c7041811;hp=8f3c6370a2e71753a7cf75421370bc90b268f290;hpb=fcc522c92335783293ac19df318415cd97fbf66b;p=musl

diff --git a/src/network/__dns.c b/src/network/__dns.c
index 8f3c6370..97d8031c 100644
--- a/src/network/__dns.c
+++ b/src/network/__dns.c
@@ -11,6 +11,7 @@
 #include <ctype.h>
 #include <unistd.h>
 #include <pthread.h>
+#include <errno.h>
 #include "__dns.h"
 #include "stdio_impl.h"
 
@@ -35,9 +36,9 @@ int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt)
 		struct sockaddr_in sin;
 		struct sockaddr_in6 sin6;
 	} sa = {0}, ns[3] = {{0}};
-	socklen_t sl;
+	socklen_t sl = sizeof sa.sin;
 	int nns = 0;
-	int family = AF_UNSPEC;
+	int family = AF_INET;
 	unsigned char q[280] = "", *r = dest;
 	int ql;
 	int rlen;
@@ -75,10 +76,12 @@ int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt)
 		for (s=line+11; isspace(*s); s++);
 		for (z=s; *z && !isspace(*z); z++);
 		*z=0;
-		if (__ipparse(ns+nns, family, s) < 0) continue;
+		if (__ipparse(ns+nns, AF_UNSPEC, s) < 0) continue;
 		ns[nns].sin.sin_port = htons(53);
-		family = ns[nns++].sin.sin_family;
-		sl = family==AF_INET6 ? sizeof sa.sin6 : sizeof sa.sin;
+		if (ns[nns++].sin.sin_family == AF_INET6) {
+			family = AF_INET6;
+			sl = sizeof sa.sin6;
+		}
 	}
 	if (f) __fclose_ca(f);
 	if (!nns) {
@@ -93,6 +96,29 @@ int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt)
 	sa.sin.sin_family = family;
 	fd = socket(family, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
 
+	/* Handle case where system lacks IPv6 support */
+	if (fd < 0 && errno == EAFNOSUPPORT) {
+		if (family != AF_INET6) return EAI_SYSTEM;
+		fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+		family = AF_INET;
+	}
+	if (fd < 0) return EAI_SYSTEM;
+
+	/* Convert any IPv4 addresses in a mixed environment to v4-mapped */
+	if (family == AF_INET6) {
+		setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &(int){0}, sizeof 0);
+		for (i=0; i<nns; i++) {
+			if (ns[i].sin.sin_family != AF_INET) continue;
+			memcpy(ns[i].sin6.sin6_addr.s6_addr+12,
+				&ns[i].sin.sin_addr, 4);
+			memcpy(ns[i].sin6.sin6_addr.s6_addr,
+				"\0\0\0\0\0\0\0\0\0\0\xff\xff", 12);
+			ns[i].sin6.sin6_family = AF_INET6;
+			ns[i].sin6.sin6_flowinfo = 0;
+			ns[i].sin6.sin6_scope_id = 0;
+		}
+	}
+
 	pthread_cleanup_push(cleanup, (void *)(intptr_t)fd);
 	pthread_setcancelstate(cs, 0);