X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fbasic%2Fsocket-util.c;h=a983c67a826a0ddcd2a49ed09f11177669b764f4;hp=86d6e3f6e1a609b020c51eded17bc7adbf766717;hb=1e2c11636861da69c5637e59afe207a11dd4f386;hpb=9facc64034a98d593cf5b577e979aa78e3b184bf

diff --git a/src/basic/socket-util.c b/src/basic/socket-util.c
index 86d6e3f6e..a983c67a8 100644
--- a/src/basic/socket-util.c
+++ b/src/basic/socket-util.c
@@ -441,7 +441,7 @@ const char* socket_address_get_path(const SocketAddress *a) {
 #endif // 0
 
 bool socket_ipv6_is_supported(void) {
-        if (access("/proc/net/sockstat6", F_OK) != 0)
+        if (access("/proc/net/if_inet6", F_OK) != 0)
                 return false;
 
         return true;
@@ -991,7 +991,7 @@ ssize_t next_datagram_size_fd(int fd) {
 
         l = recv(fd, NULL, 0, MSG_PEEK|MSG_TRUNC);
         if (l < 0) {
-                if (errno == EOPNOTSUPP)
+                if (errno == EOPNOTSUPP || errno == EFAULT)
                         goto fallback;
 
                 return -errno;
@@ -1052,3 +1052,34 @@ int flush_accept(int fd) {
         }
 }
 #endif // 0
+
+struct cmsghdr* cmsg_find(struct msghdr *mh, int level, int type, socklen_t length) {
+        struct cmsghdr *cmsg;
+
+        assert(mh);
+
+        CMSG_FOREACH(cmsg, mh)
+                if (cmsg->cmsg_level == level &&
+                    cmsg->cmsg_type == type &&
+                    (length == (socklen_t) -1 || length == cmsg->cmsg_len))
+                        return cmsg;
+
+        return NULL;
+}
+
+int socket_ioctl_fd(void) {
+        int fd;
+
+        /* Create a socket to invoke the various network interface ioctl()s on. Traditionally only AF_INET was good for
+         * that. Since kernel 4.6 AF_NETLINK works for this too. We first try to use AF_INET hence, but if that's not
+         * available (for example, because it is made unavailable via SECCOMP or such), we'll fall back to the more
+         * generic AF_NETLINK. */
+
+        fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC, 0);
+        if (fd < 0)
+                fd = socket(AF_NETLINK, SOCK_RAW|SOCK_CLOEXEC, NETLINK_GENERIC);
+        if (fd < 0)
+                return -errno;
+
+        return fd;
+}