* @udev: udev library context
* @socket_path: unix socket path
*
- * Create new udev monitor, setup and connect to a specified socket. The
- * path to a socket can point to an existing socket file, or it will be
- * created if needed. If neccessary, the permissions adjustment as well as
- * the later cleanup of the socket file, needs to be done by the caller.
- * If the socket path starts with a '@' character, an abstract namespace
+ * Create new udev monitor and connect to a specified socket. The
+ * path to a socket either points to an existing socket file, or if
+ * the socket path starts with a '@' character, an abstract namespace
* socket will be used.
*
+ * A socket file will not be created. If it does not already exist,
+ * it will fall-back and connect to an abstract namespace socket with
+ * the given path. The permissions adjustment of a socket file, as
+ * well as the later cleanup, needs to be done by the caller.
+ *
* The initial refcount is 1, and needs to be decremented to
* release the resources of the udev monitor.
*
free(udev_monitor);
return NULL;
}
+ util_set_fd_cloexec(udev_monitor->sock);
+
dbg(udev, "monitor %p created with '%s'\n", udev_monitor, socket_path);
return udev_monitor;
}
+/**
+ * udev_monitor_new_from_netlink:
+ * @udev: udev library context
+ * @name: name of event source
+ *
+ * Create new udev monitor and connect to a specified event
+ * source. Valid sources identifiers are "udev" and "kernel".
+ *
+ * Applications should usually not connect directly to the
+ * "kernel" events, because the devices might not be useable
+ * at that time, before udev has configured them, and created
+ * device nodes.
+ *
+ * Accessing devices at the same time as udev, might result
+ * in unpredictable behavior.
+ *
+ * The "udev" events are sent out after udev has finished its
+ * event processing, all rules have been processed, and needed
+ * device nodes are created.
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev monitor.
+ *
+ * Returns: a new udev monitor, or #NULL, in case of an error
+ **/
struct udev_monitor *udev_monitor_new_from_netlink(struct udev *udev, const char *name)
{
struct udev_monitor *udev_monitor;
free(udev_monitor);
return NULL;
}
+ util_set_fd_cloexec(udev_monitor->sock);
udev_monitor->snl.nl_family = AF_NETLINK;
udev_monitor->snl.nl_groups = group;
int err;
const int on = 1;
- if (udev_monitor->snl.nl_family != 0) {
- err = bind(udev_monitor->sock,
- (struct sockaddr *)&udev_monitor->snl, sizeof(struct sockaddr_nl));
- if (err < 0) {
- err(udev_monitor->udev, "bind failed: %m\n");
- return err;
- }
- dbg(udev_monitor->udev, "monitor %p listening on netlink\n", udev_monitor);
- } else if (udev_monitor->sun.sun_family != 0) {
+ if (udev_monitor->sun.sun_family != 0)
err = bind(udev_monitor->sock,
(struct sockaddr *)&udev_monitor->sun, udev_monitor->addrlen);
- if (err < 0) {
- err(udev_monitor->udev, "bind failed: %m\n");
- return err;
- }
- /* enable receiving of the sender credentials */
- setsockopt(udev_monitor->sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on));
- dbg(udev_monitor->udev, "monitor %p listening on socket\n", udev_monitor);
+ else if (udev_monitor->snl.nl_family != 0)
+ err = bind(udev_monitor->sock,
+ (struct sockaddr *)&udev_monitor->snl, sizeof(struct sockaddr_nl));
+ else
+ return -EINVAL;
+
+ if (err < 0) {
+ err(udev_monitor->udev, "bind failed: %m\n");
+ return err;
}
+
+ /* enable receiving of sender credentials */
+ setsockopt(udev_monitor->sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on));
return 0;
}
* udev_monitor_unref:
* @udev_monitor: udev monitor
*
- * Drop a reference ofa udev monitor. If the refcount reaches zero,
+ * Drop a reference of a udev monitor. If the refcount reaches zero,
* the bound socket will be closed, and the resources of the monitor
* will be released.
*
struct msghdr smsg;
struct iovec iov;
char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
+ struct cmsghdr *cmsg;
+ struct sockaddr_nl snl;
+ struct ucred *cred;
char buf[4096];
size_t bufpos;
int devpath_set = 0;
smsg.msg_control = cred_msg;
smsg.msg_controllen = sizeof(cred_msg);
+ if (udev_monitor->snl.nl_family != 0) {
+ smsg.msg_name = &snl;
+ smsg.msg_namelen = sizeof snl;
+ }
+
if (recvmsg(udev_monitor->sock, &smsg, 0) < 0) {
if (errno != EINTR)
- info(udev_monitor->udev, "unable to receive message");
+ info(udev_monitor->udev, "unable to receive message\n");
return NULL;
}
- if (udev_monitor->sun.sun_family != 0) {
- struct cmsghdr *cmsg = CMSG_FIRSTHDR(&smsg);
- struct ucred *cred = (struct ucred *)CMSG_DATA (cmsg);
-
- if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
- info(udev_monitor->udev, "no sender credentials received, message ignored");
+ if (udev_monitor->snl.nl_family != 0) {
+ if (snl.nl_groups == 0) {
+ info(udev_monitor->udev, "unicast netlink message ignored\n");
return NULL;
}
-
- if (cred->uid != 0) {
- info(udev_monitor->udev, "sender uid=%d, message ignored", cred->uid);
+ if ((snl.nl_groups == UDEV_MONITOR_KERNEL) && (snl.nl_pid > 0)) {
+ info(udev_monitor->udev, "multicast kernel netlink message from pid %d ignored\n", snl.nl_pid);
return NULL;
}
}
+ cmsg = CMSG_FIRSTHDR(&smsg);
+ if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
+ info(udev_monitor->udev, "no sender credentials received, message ignored\n");
+ return NULL;
+ }
+
+ cred = (struct ucred *)CMSG_DATA(cmsg);
+ if (cred->uid != 0) {
+ info(udev_monitor->udev, "sender uid=%d, message ignored\n", cred->uid);
+ return NULL;
+ }
+
/* skip header */
bufpos = strlen(buf) + 1;
if (bufpos < sizeof("a@/d") || bufpos >= sizeof(buf)) {
- info(udev_monitor->udev, "invalid message length");
+ info(udev_monitor->udev, "invalid message length\n");
return NULL;
}
/* check message header */
if (strstr(buf, "@/") == NULL) {
- info(udev_monitor->udev, "unrecognized message header");
+ info(udev_monitor->udev, "unrecognized message header\n");
return NULL;
}
len = udev_device_get_properties_monitor_buf(udev_device, &buf);
if (len < 32)
return -1;
- if (udev_monitor->sun.sun_family != 0) {
+ if (udev_monitor->sun.sun_family != 0)
count = sendto(udev_monitor->sock,
buf, len, 0,
(struct sockaddr *)&udev_monitor->sun,
udev_monitor->addrlen);
- } else {
- /* no destination besides the muticast group, we will always get -1 ECONNREFUSED */
+ else if (udev_monitor->snl.nl_family != 0)
+ /* no destination besides the muticast group, we will always get ECONNREFUSED */
count = sendto(udev_monitor->sock,
buf, len, 0,
(struct sockaddr *)&udev_monitor->snl_peer,
sizeof(struct sockaddr_nl));
- }
- info(udev_monitor->udev, "passed %zi bytes to monitor %p, \n", count, udev_monitor);
+ else
+ return -1;
+
+ info(udev_monitor->udev, "passed %zi bytes to monitor %p\n", count, udev_monitor);
return count;
}
~ianmdlvl / elogind.git / blobdiff