Support older linux without SOCK_CLOEXEC.

diff --git a/if-linux.c b/if-linux.c
index 472cbf8d506467c4af1e30a163dbe4e2794d551a..9690ea8877a00109f8f958e85bc20256ea2c183f 100644 (file)
--- a/if-linux.c
+++ b/if-linux.c
@@ -217,9 +217,23 @@ _open_link_socket(struct sockaddr_nl *nl)
 {
        int fd;
 
+#ifdef SOCK_CLOEXEC
        fd = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, NETLINK_ROUTE);
        if (fd == -1)
                return -1;
+#else
+       int flags;
+
+       fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+       if (fd == -1)
+               return -1;
+       if ((flags = fcntl(fd, F_GETFD, 0)) == -1 ||
+           fcntl(fd, F_SETFD, flags | FD_CLOEXEC) == -1)
+       {
+               close(fd);
+               return -1;
+       }
+#endif
        nl->nl_family = AF_NETLINK;
        if (bind(fd, (struct sockaddr *)nl, sizeof(*nl)) == -1)
                return -1;
@@ -739,11 +753,28 @@ ipv4_opensocket(struct interface *ifp, int protocol)
        int n;
 #endif
 
+#ifdef SOCK_CLOEXEC
        if ((s = socket(PF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
            htons(protocol))) == -1)
                return -1;
+#else
+       int flags;
 
-       memset(&su, 0, sizeof(su));
+       if ((s = socket(PF_PACKET, SOCK_DGRAM, htons(protocol))) == -1)
+               return -1;
+       if ((flags = fcntl(s, F_GETFD, 0)) == -1 ||
+           fcntl(s, F_SETFD, flags | FD_CLOEXEC) == -1)
+       {
+               close(s);
+               return -1;
+       }
+       if ((flags = fcntl(s, F_GETFL, 0)) == -1 ||
+           fcntl(s, F_SETFL, flags | O_NONBLOCK) == -1)
+       {
+               close(s);
+               return -1;
+       }
+#endif
        su.sll.sll_family = PF_PACKET;
        su.sll.sll_protocol = htons(protocol);
        su.sll.sll_ifindex = (int)ifp->index;