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Diffstat (limited to 'src/udev/udev-event.c')
-rw-r--r--src/udev/udev-event.c129
1 files changed, 87 insertions, 42 deletions
diff --git a/src/udev/udev-event.c b/src/udev/udev-event.c
index 7cf82fd8a6..0779ebc30b 100644
--- a/src/udev/udev-event.c
+++ b/src/udev/udev-event.c
@@ -752,36 +752,18 @@ out:
}
#ifdef ENABLE_RULE_GENERATOR
-static void rename_netif_kernel_log(struct ifreq ifr)
-{
- int klog;
- FILE *f;
-
- klog = open("/dev/kmsg", O_WRONLY|O_CLOEXEC);
- if (klog < 0)
- return;
-
- f = fdopen(klog, "w");
- if (f == NULL) {
- close(klog);
- return;
- }
-
- fprintf(f, "<30>udevd[%u]: renamed network interface %s to %s\n",
- getpid(), ifr.ifr_name, ifr.ifr_newname);
- fclose(f);
-}
+/* function to return the count of rules that assign NAME= to a value matching arg#2 , defined in udev-rules.c */
+int udev_rules_assigning_name_to(struct udev_rules *rules,const char *match_name);
#endif
-static int rename_netif(struct udev_event *event)
+static int rename_netif_dev_fromname_toname(struct udev_device *dev,const char *oldname,const char *newname)
{
- struct udev_device *dev = event->dev;
int sk;
struct ifreq ifr;
int err;
log_debug("changing net interface name from '%s' to '%s'\n",
- udev_device_get_sysname(dev), event->name);
+ oldname, newname);
sk = socket(PF_INET, SOCK_DGRAM, 0);
if (sk < 0) {
@@ -791,37 +773,26 @@ static int rename_netif(struct udev_event *event)
}
memset(&ifr, 0x00, sizeof(struct ifreq));
- strscpy(ifr.ifr_name, IFNAMSIZ, udev_device_get_sysname(dev));
- strscpy(ifr.ifr_newname, IFNAMSIZ, event->name);
+ strscpy(ifr.ifr_name, IFNAMSIZ, oldname);
+ strscpy(ifr.ifr_newname, IFNAMSIZ, newname);
err = ioctl(sk, SIOCSIFNAME, &ifr);
#ifdef ENABLE_RULE_GENERATOR
int loop;
if (err == 0) {
- rename_netif_kernel_log(ifr);
+ print_kmsg("renamed network interface %s to %s\n", ifr.ifr_name, ifr.ifr_newname);
goto out;
}
-
/* keep trying if the destination interface name already exists */
+ log_debug("collision on rename of network interface %s to %s , retrying until timeout\n",
+ ifr.ifr_name, ifr.ifr_newname);
+
err = -errno;
if (err != -EEXIST)
goto out;
- /* free our own name, another process may wait for us */
- snprintf(ifr.ifr_newname, IFNAMSIZ, "rename%u", udev_device_get_ifindex(dev));
- err = ioctl(sk, SIOCSIFNAME, &ifr);
- if (err < 0) {
- err = -errno;
- goto out;
- }
-
- /* log temporary name */
- rename_netif_kernel_log(ifr);
-
/* wait a maximum of 90 seconds for our target to become available */
- strscpy(ifr.ifr_name, IFNAMSIZ, ifr.ifr_newname);
- strscpy(ifr.ifr_newname, IFNAMSIZ, event->name);
loop = 90 * 20;
while (loop--) {
const struct timespec duration = { 0, 1000 * 1000 * 1000 / 20 };
@@ -830,7 +801,7 @@ static int rename_netif(struct udev_event *event)
err = ioctl(sk, SIOCSIFNAME, &ifr);
if (err == 0) {
- rename_netif_kernel_log(ifr);
+ print_kmsg("renamed network interface %s to %s\n", ifr.ifr_name, ifr.ifr_newname);
break;
}
err = -errno;
@@ -854,6 +825,11 @@ out:
return err;
}
+static int rename_netif(struct udev_event *event)
+{
+ return rename_netif_dev_fromname_toname(event->dev,udev_device_get_sysname(event->dev),event->name);
+}
+
int udev_event_execute_rules(struct udev_event *event, struct udev_rules *rules, const sigset_t *sigmask)
{
struct udev_device *dev = event->dev;
@@ -890,14 +866,83 @@ int udev_event_execute_rules(struct udev_event *event, struct udev_rules *rules,
udev_rules_apply_to_event(rules, event, sigmask);
/* rename a new network interface, if needed */
+
+ /* ENABLE_RULE_GENERATOR conditional:
+ * if this is a net iface, and it is an add event,
+ * and as long as all of the following are FALSE:
+ * - no NAME target and the current name is not being used
+ * - there is a NAME target and it is the same as the current name
+ * - the rules can successfully be searched for the current name (not really part of the conditional)
+ * the run the rename.
+ *
+ * note - udev_rules_assigning_name_to is run when event->name is NULL to ensure renames happen,
+ * but also on its own to check if a temp-rename is necessary when event->name exists.
+ *
+ * A temp-rename is necessary when:
+ * - there is no rule renaming the current iface but the current name IS used in some other rule
+ * - there is a rule renaming the current iface,
+ * the current name IS used AND the target name != the current name
+ */
+
if (udev_device_get_ifindex(dev) > 0 && streq(udev_device_get_action(dev), "add") &&
+#ifdef ENABLE_RULE_GENERATOR
+ (event->name == NULL && (err=udev_rules_assigning_name_to(rules,udev_device_get_sysname(dev))) > 0 ||
+ event->name != NULL && !streq(event->name, udev_device_get_sysname(dev)))) {
+#else
event->name != NULL && !streq(event->name, udev_device_get_sysname(dev))) {
+#endif
char syspath[UTIL_PATH_SIZE];
char *pos;
+ char *finalifname = event->name;
+#ifdef ENABLE_RULE_GENERATOR
+ char newifname[IFNAMSIZ];
+
+ /* err is the number of rules that assign a device with NAME= this sysname */
+ if (err > 0 || (err=udev_rules_assigning_name_to(rules,udev_device_get_sysname(dev))) > 0) {
+ /* have a conflict, rename to a temp name */
+ char *newpos;
+ int ifidnum;
+
+ /* build the temporary iface name */
+ strscpy(newifname, IFNAMSIZ, udev_device_get_sysname(dev));
+ newpos=pos=&newifname[strcspn(newifname,"0123456789")];
+ ifidnum=(int)strtol(pos,&newpos,10);
+ *pos='\0';
+ if (newpos > pos && *newpos == '\0') /* append new iface num to name */
+ /* use udev_device_get_ifindex(dev) as it is unique to every iface */
+ snprintf(pos,IFNAMSIZ+(newifname-pos), "%d", 128 - udev_device_get_ifindex(dev));
+
+ /* note, err > 0, which will skip the post-rename stuff if no rename occurs */
+
+ /* if sysname isn't already the tmpname (ie there is no numeric component), do the rename */
+ if (!streq(newifname,udev_device_get_sysname(dev))) {
+ err = rename_netif_dev_fromname_toname(dev,udev_device_get_sysname(dev),newifname);
+ if (err == 0) {
+ finalifname = newifname;
+ log_debug("renamed netif to '%s' for collision avoidance\n", newifname);
+ } else {
+ log_error("could not rename netif to '%s' for collision avoidance\n",newifname);
+ }
+ }
+ /* rename it now to its final target if its not already there */
+ if (event->name != NULL && !streq(event->name, newifname)) {
+ err = rename_netif_dev_fromname_toname(dev,newifname,event->name);
+ if (err == 0)
+ finalifname = event->name;
+ }
+
+ } else { /* no need to rename to a tempname first, do a regular direct rename to event->name */
+
+ err = 1; /* skip the post-rename stuff if no rename occurs */
+ if (!streq(event->name, udev_device_get_sysname(dev)))
+ err = rename_netif(event);
+ }
+#else
err = rename_netif(event);
+#endif
if (err == 0) {
- log_debug("renamed netif to '%s'\n", event->name);
+ log_debug("renamed netif to '%s'\n", finalifname);
/* remember old name */
udev_device_add_property(dev, "INTERFACE_OLD", udev_device_get_sysname(dev));
@@ -907,7 +952,7 @@ int udev_event_execute_rules(struct udev_event *event, struct udev_rules *rules,
pos = strrchr(syspath, '/');
if (pos != NULL) {
pos++;
- strscpy(pos, sizeof(syspath) - (pos - syspath), event->name);
+ strscpy(pos, sizeof(syspath) - (pos - syspath), finalifname);
udev_device_set_syspath(event->dev, syspath);
udev_device_add_property(dev, "INTERFACE", udev_device_get_sysname(dev));
log_debug("changed devpath to '%s'\n", udev_device_get_devpath(dev));
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-09-16 11:27:43 +0000