remove unused variable

[elogind.git] / src / libudev / libudev-monitor.c

diff --git a/src/libudev/libudev-monitor.c b/src/libudev/libudev-monitor.c
index b02ea8808cf949a41de9caca803dba7e7b859f01..ea7263f2808a6721b542a099a6dd83e907bd73ff 100644 (file)
--- a/src/libudev/libudev-monitor.c
+++ b/src/libudev/libudev-monitor.c
@@ -35,6 +35,7 @@
 #include "libudev.h"
 #include "libudev-private.h"
 #include "socket-util.h"
 #include "libudev.h"
 #include "libudev-private.h"
 #include "socket-util.h"

+#include "missing.h"

 
 /**
  * SECTION:libudev-monitor
 
 /**
  * SECTION:libudev-monitor


@@ -105,6 +106,61 @@ static struct udev_monitor *udev_monitor_new(struct udev *udev)
         return udev_monitor;
 }
 
         return udev_monitor;
 }
 

+/* we consider udev running when /dev is on devtmpfs */
+static bool udev_has_devtmpfs(struct udev *udev) {
+        struct file_handle *h;
+        int mount_id;
+        _cleanup_fclose_ FILE *f = NULL;
+        char line[LINE_MAX], *e;
+        int r;
+
+        h = alloca(MAX_HANDLE_SZ);
+        h->handle_bytes = MAX_HANDLE_SZ;
+        r = name_to_handle_at(AT_FDCWD, "/dev", h, &mount_id, 0);
+        if (r < 0)
+                return false;
+
+
+        f = fopen("/proc/self/mountinfo", "re");
+        if (!f)
+                return false;
+
+        FOREACH_LINE(line, f, return false) {
+                int mid;
+
+                if (sscanf(line, "%i", &mid) != 1)
+                        continue;
+
+                if (mid != mount_id)
+                        continue;
+
+                e = strstr(line, " - ");
+                if (!e)
+                        continue;
+
+                /* accept any name that starts with the currently expected type */
+                if (startswith(e + 3, "devtmpfs"))
+                        return true;
+        }
+
+        return false;
+}
+
+/* we consider udev running when we have running udev service */
+static bool udev_has_service(struct udev *udev) {
+        struct udev_queue *queue;
+        bool active;
+
+        queue = udev_queue_new(udev);
+        if (!queue)
+                return false;
+
+        active = udev_queue_get_udev_is_active(queue);
+        udev_queue_unref(queue);
+
+        return active;
+}
+

 struct udev_monitor *udev_monitor_new_from_netlink_fd(struct udev *udev, const char *name, int fd)
 {
         struct udev_monitor *udev_monitor;
 struct udev_monitor *udev_monitor_new_from_netlink_fd(struct udev *udev, const char *name, int fd)
 {
         struct udev_monitor *udev_monitor;


@@ -115,9 +171,25 @@ struct udev_monitor *udev_monitor_new_from_netlink_fd(struct udev *udev, const c
 
         if (name == NULL)
                 group = UDEV_MONITOR_NONE;
 
         if (name == NULL)
                 group = UDEV_MONITOR_NONE;

-        else if (strcmp(name, "udev") == 0)
-                group = UDEV_MONITOR_UDEV;
-        else if (strcmp(name, "kernel") == 0)
+        else if (streq(name, "udev")) {
+                /*
+                 * We do not support subscribing to uevents if no instance of
+                 * udev is running. Uevents would otherwise broadcast the
+                 * processing data of the host into containers, which is not
+                 * desired.
+                 *
+                 * Containers will currently not get any udev uevents, until
+                 * a supporting infrastructure is available.
+                 *
+                 * We do not set a netlink multicast group here, so the socket
+                 * will not receive any messages.
+                 */
+                if (!udev_has_service(udev) && !udev_has_devtmpfs(udev)) {
+                        udev_dbg(udev, "the udev service seems not to be active, disable the monitor\n");
+                        group = UDEV_MONITOR_NONE;
+                } else
+                        group = UDEV_MONITOR_UDEV;
+        } else if (streq(name, "kernel"))

                 group = UDEV_MONITOR_KERNEL;
         else
                 return NULL;
                 group = UDEV_MONITOR_KERNEL;
         else
                 return NULL;


@@ -288,7 +360,7 @@ _public_ int udev_monitor_filter_update(struct udev_monitor *udev_monitor)
                         bpf_stmt(ins, &i, BPF_RET|BPF_K, 0xffffffff);
 
                         if (i+1 >= ELEMENTSOF(ins))
                         bpf_stmt(ins, &i, BPF_RET|BPF_K, 0xffffffff);
 
                         if (i+1 >= ELEMENTSOF(ins))

-                                return -1;
+                                return -E2BIG;

                 }
 
                 /* nothing matched, drop packet */
                 }
 
                 /* nothing matched, drop packet */


@@ -303,7 +375,7 @@ _public_ int udev_monitor_filter_update(struct udev_monitor *udev_monitor)
         filter.len = i;
         filter.filter = ins;
         err = setsockopt(udev_monitor->sock, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter));
         filter.len = i;
         filter.filter = ins;
         err = setsockopt(udev_monitor->sock, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter));

-        return err;
+        return err < 0 ? -errno : 0;

 }
 
 int udev_monitor_allow_unicast_sender(struct udev_monitor *udev_monitor, struct udev_monitor *sender)
 }
 
 int udev_monitor_allow_unicast_sender(struct udev_monitor *udev_monitor, struct udev_monitor *sender)


@@ -324,9 +396,6 @@ _public_ int udev_monitor_enable_receiving(struct udev_monitor *udev_monitor)
         int err = 0;
         const int on = 1;
 
         int err = 0;
         const int on = 1;
 

-        if (udev_monitor->snl.nl.nl_family == 0)
-                return -EINVAL;
-

         udev_monitor_filter_update(udev_monitor);
 
         if (!udev_monitor->bound) {
         udev_monitor_filter_update(udev_monitor);
 
         if (!udev_monitor->bound) {


@@ -350,7 +419,7 @@ _public_ int udev_monitor_enable_receiving(struct udev_monitor *udev_monitor)
                         udev_monitor->snl.nl.nl_pid = snl.nl.nl_pid;
         } else {
                 udev_err(udev_monitor->udev, "bind failed: %m\n");
                         udev_monitor->snl.nl.nl_pid = snl.nl.nl_pid;
         } else {
                 udev_err(udev_monitor->udev, "bind failed: %m\n");

-                return err;
+                return -errno;

         }
 
         /* enable receiving of sender credentials */
         }
 
         /* enable receiving of sender credentials */


@@ -371,7 +440,7 @@ _public_ int udev_monitor_enable_receiving(struct udev_monitor *udev_monitor)
 _public_ int udev_monitor_set_receive_buffer_size(struct udev_monitor *udev_monitor, int size)
 {
         if (udev_monitor == NULL)
 _public_ int udev_monitor_set_receive_buffer_size(struct udev_monitor *udev_monitor, int size)
 {
         if (udev_monitor == NULL)

-                return -1;
+                return -EINVAL;

         return setsockopt(udev_monitor->sock, SOL_SOCKET, SO_RCVBUFFORCE, &size, sizeof(size));
 }
 
         return setsockopt(udev_monitor->sock, SOL_SOCKET, SO_RCVBUFFORCE, &size, sizeof(size));
 }
 


@@ -381,7 +450,7 @@ int udev_monitor_disconnect(struct udev_monitor *udev_monitor)
 
         err = close(udev_monitor->sock);
         udev_monitor->sock = -1;
 
         err = close(udev_monitor->sock);
         udev_monitor->sock = -1;

-        return err;
+        return err < 0 ? -errno : 0;

 }
 
 /**
 }
 
 /**


@@ -408,7 +477,7 @@ _public_ struct udev_monitor *udev_monitor_ref(struct udev_monitor *udev_monitor
  * the bound socket will be closed, and the resources of the monitor
  * will be released.
  *
  * the bound socket will be closed, and the resources of the monitor
  * will be released.
  *

- * Returns: the passed udev monitor if it has still an active reference, or #NULL otherwise.
+ * Returns: #NULL

  **/
 _public_ struct udev_monitor *udev_monitor_unref(struct udev_monitor *udev_monitor)
 {
  **/
 _public_ struct udev_monitor *udev_monitor_unref(struct udev_monitor *udev_monitor)
 {


@@ -416,7 +485,7 @@ _public_ struct udev_monitor *udev_monitor_unref(struct udev_monitor *udev_monit
                 return NULL;
         udev_monitor->refcount--;
         if (udev_monitor->refcount > 0)
                 return NULL;
         udev_monitor->refcount--;
         if (udev_monitor->refcount > 0)

-                return udev_monitor;
+                return NULL;

         if (udev_monitor->sock >= 0)
                 close(udev_monitor->sock);
         udev_list_cleanup(&udev_monitor->filter_subsystem_list);
         if (udev_monitor->sock >= 0)
                 close(udev_monitor->sock);
         udev_list_cleanup(&udev_monitor->filter_subsystem_list);


@@ -451,7 +520,7 @@ _public_ struct udev *udev_monitor_get_udev(struct udev_monitor *udev_monitor)
 _public_ int udev_monitor_get_fd(struct udev_monitor *udev_monitor)
 {
         if (udev_monitor == NULL)
 _public_ int udev_monitor_get_fd(struct udev_monitor *udev_monitor)
 {
         if (udev_monitor == NULL)

-                return -1;
+                return -EINVAL;

         return udev_monitor->sock;
 }
 
         return udev_monitor->sock;
 }
 


@@ -467,7 +536,7 @@ static int passes_filter(struct udev_monitor *udev_monitor, struct udev_device *
                 const char *devtype;
                 const char *ddevtype;
 
                 const char *devtype;
                 const char *ddevtype;
 

-                if (strcmp(dsubsys, subsys) != 0)
+                if (!streq(dsubsys, subsys))

                         continue;
 
                 devtype = udev_list_entry_get_value(list_entry);
                         continue;
 
                 devtype = udev_list_entry_get_value(list_entry);


@@ -476,7 +545,7 @@ static int passes_filter(struct udev_monitor *udev_monitor, struct udev_device *
                 ddevtype = udev_device_get_devtype(udev_device);
                 if (ddevtype == NULL)
                         continue;
                 ddevtype = udev_device_get_devtype(udev_device);
                 if (ddevtype == NULL)
                         continue;

-                if (strcmp(ddevtype, devtype) == 0)
+                if (streq(ddevtype, devtype))

                         goto tag;
         }
         return 0;
                         goto tag;
         }
         return 0;


@@ -524,7 +593,6 @@ _public_ struct udev_device *udev_monitor_receive_device(struct udev_monitor *ud
         char buf[8192];
         ssize_t buflen;
         ssize_t bufpos;
         char buf[8192];
         ssize_t buflen;
         ssize_t bufpos;

-        struct udev_monitor_netlink_header *nlh;

 
 retry:
         if (udev_monitor == NULL)
 
 retry:
         if (udev_monitor == NULL)


@@ -536,11 +604,8 @@ retry:
         smsg.msg_iovlen = 1;
         smsg.msg_control = cred_msg;
         smsg.msg_controllen = sizeof(cred_msg);
         smsg.msg_iovlen = 1;
         smsg.msg_control = cred_msg;
         smsg.msg_controllen = sizeof(cred_msg);

-
-        if (udev_monitor->snl.nl.nl_family != 0) {
-                smsg.msg_name = &snl;
-                smsg.msg_namelen = sizeof(snl);
-        }
+        smsg.msg_name = &snl;
+        smsg.msg_namelen = sizeof(snl);

 
         buflen = recvmsg(udev_monitor->sock, &smsg, 0);
         if (buflen < 0) {
 
         buflen = recvmsg(udev_monitor->sock, &smsg, 0);
         if (buflen < 0) {


@@ -554,20 +619,18 @@ retry:
                 return NULL;
         }
 
                 return NULL;
         }
 

-        if (udev_monitor->snl.nl.nl_family != 0) {
-                if (snl.nl.nl_groups == 0) {
-                        /* unicast message, check if we trust the sender */
-                        if (udev_monitor->snl_trusted_sender.nl.nl_pid == 0 ||
-                            snl.nl.nl_pid != udev_monitor->snl_trusted_sender.nl.nl_pid) {
-                                udev_dbg(udev_monitor->udev, "unicast netlink message ignored\n");
-                                return NULL;
-                        }
-                } else if (snl.nl.nl_groups == UDEV_MONITOR_KERNEL) {
-                        if (snl.nl.nl_pid > 0) {
-                                udev_dbg(udev_monitor->udev, "multicast kernel netlink message from pid %d ignored\n",
-                                     snl.nl.nl_pid);
-                                return NULL;
-                        }
+        if (snl.nl.nl_groups == 0) {
+                /* unicast message, check if we trust the sender */
+                if (udev_monitor->snl_trusted_sender.nl.nl_pid == 0 ||
+                    snl.nl.nl_pid != udev_monitor->snl_trusted_sender.nl.nl_pid) {
+                        udev_dbg(udev_monitor->udev, "unicast netlink message ignored\n");
+                        return NULL;
+                }
+        } else if (snl.nl.nl_groups == UDEV_MONITOR_KERNEL) {
+                if (snl.nl.nl_pid > 0) {
+                        udev_dbg(udev_monitor->udev, "multicast kernel netlink message from pid %d ignored\n",
+                             snl.nl.nl_pid);
+                        return NULL;

                 }
         }
 
                 }
         }
 


@@ -583,35 +646,47 @@ retry:
                 return NULL;
         }
 
                 return NULL;
         }
 

+        udev_device = udev_device_new(udev_monitor->udev);
+        if (udev_device == NULL)
+                return NULL;
+

         if (memcmp(buf, "libudev", 8) == 0) {
         if (memcmp(buf, "libudev", 8) == 0) {

+                struct udev_monitor_netlink_header *nlh;
+

                 /* udev message needs proper version magic */
                 nlh = (struct udev_monitor_netlink_header *) buf;
                 if (nlh->magic != htonl(UDEV_MONITOR_MAGIC)) {
                         udev_err(udev_monitor->udev, "unrecognized message signature (%x != %x)\n",
                 /* udev message needs proper version magic */
                 nlh = (struct udev_monitor_netlink_header *) buf;
                 if (nlh->magic != htonl(UDEV_MONITOR_MAGIC)) {
                         udev_err(udev_monitor->udev, "unrecognized message signature (%x != %x)\n",

-                            nlh->magic, htonl(UDEV_MONITOR_MAGIC));
+                                 nlh->magic, htonl(UDEV_MONITOR_MAGIC));
+                        udev_device_unref(udev_device);

                         return NULL;
                 }
                         return NULL;
                 }

-                if (nlh->properties_off+32 > (size_t)buflen)
+                if (nlh->properties_off+32 > (size_t)buflen) {
+                        udev_device_unref(udev_device);

                         return NULL;
                         return NULL;

+                }
+

                 bufpos = nlh->properties_off;
                 bufpos = nlh->properties_off;

+
+                /* devices received from udev are always initialized */
+                udev_device_set_is_initialized(udev_device);

         } else {
                 /* kernel message with header */
                 bufpos = strlen(buf) + 1;
                 if ((size_t)bufpos < sizeof("a@/d") || bufpos >= buflen) {
                         udev_dbg(udev_monitor->udev, "invalid message length\n");
         } else {
                 /* kernel message with header */
                 bufpos = strlen(buf) + 1;
                 if ((size_t)bufpos < sizeof("a@/d") || bufpos >= buflen) {
                         udev_dbg(udev_monitor->udev, "invalid message length\n");

+                        udev_device_unref(udev_device);

                         return NULL;
                 }
 
                 /* check message header */
                 if (strstr(buf, "@/") == NULL) {
                         udev_dbg(udev_monitor->udev, "unrecognized message header\n");
                         return NULL;
                 }
 
                 /* check message header */
                 if (strstr(buf, "@/") == NULL) {
                         udev_dbg(udev_monitor->udev, "unrecognized message header\n");

+                        udev_device_unref(udev_device);

                         return NULL;
                 }
         }
 
                         return NULL;
                 }
         }
 

-        udev_device = udev_device_new(udev_monitor->udev);
-        if (udev_device == NULL)
-                return NULL;

         udev_device_set_info_loaded(udev_device);
 
         while (bufpos < buflen) {
         udev_device_set_info_loaded(udev_device);
 
         while (bufpos < buflen) {


@@ -664,9 +739,6 @@ int udev_monitor_send_device(struct udev_monitor *udev_monitor,
         struct udev_list_entry *list_entry;
         uint64_t tag_bloom_bits;
 
         struct udev_list_entry *list_entry;
         uint64_t tag_bloom_bits;
 

-        if (udev_monitor->snl.nl.nl_family == 0)
-                return -EINVAL;
-

         blen = udev_device_get_properties_monitor_buf(udev_device, &buf);
         if (blen < 32)
                 return -EINVAL;
         blen = udev_device_get_properties_monitor_buf(udev_device, &buf);
         if (blen < 32)
                 return -EINVAL;