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log to console if syslog is not available
[elogind.git] / udev_remove.c
index 7ad7c24..cff940c 100644 (file)
@@ -1,10 +1,8 @@
 /*
  * udev-remove.c
  *
- * Userspace devfs
- *
  * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
- *
+ * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
  *
  *     This program is free software; you can redistribute it and/or modify it
  *     under the terms of the GNU General Public License as published by the
 
 #include <stdlib.h>
 #include <string.h>
+#include <stddef.h>
 #include <stdio.h>
 #include <fcntl.h>
 #include <unistd.h>
 #include <errno.h>
+#include <sys/stat.h>
 
+#include "udev_libc_wrapper.h"
 #include "udev.h"
-#include "udev_lib.h"
+#include "udev_utils.h"
 #include "udev_version.h"
+#include "udev_db.h"
 #include "logging.h"
-#include "namedev.h"
-#include "udevdb.h"
 
-static int delete_path(char *path)
+static int delete_path(const char *path)
 {
        char *pos;
        int retval;
@@ -65,126 +65,96 @@ static int delete_path(char *path)
        return 0;
 }
 
-/** Remove all permissions on the device node, before
-  * unlinking it. This fixes a security issue.
-  * If the user created a hard-link to the device node,
-  * he can't use it any longer, because he lost permission
-  * to do so.
-  */
-static int secure_unlink(const char *filename)
+static int delete_node(struct udevice *udev)
 {
+       char filename[PATH_SIZE];
+       char partitionname[PATH_SIZE];
+       struct name_entry *name_loop;
+       struct stat stats;
        int retval;
+       int i;
+       int num;
 
-       retval = chown(filename, 0, 0);
-       if (retval) {
-               dbg("chown(%s, 0, 0) failed with error '%s'",
-                   filename, strerror(errno));
-               /* We continue nevertheless.
-                * I think it's very unlikely for chown
-                * to fail here, if the file exists.
-                */
-       }
-       retval = chmod(filename, 0000);
-       if (retval) {
-               dbg("chmod(%s, 0000) failed with error '%s'",
-                   filename, strerror(errno));
-               /* We continue nevertheless. */
-       }
-       retval = unlink(filename);
-       if (errno == ENOENT)
-               retval = 0;
-       if (retval) {
-               dbg("unlink(%s) failed with error '%s'",
-                       filename, strerror(errno));
+       list_for_each_entry(name_loop, &udev->symlink_list, node) {
+               snprintf(filename, sizeof(filename), "%s/%s", udev_root, name_loop->name);
+               filename[sizeof(filename)-1] = '\0';
+
+               if (stat(filename, &stats) != 0) {
+                       dbg("symlink '%s' not found", filename);
+                       continue;
+               }
+               if (udev->devt && stats.st_rdev != udev->devt) {
+                       info("symlink '%s' points to a different device, skip removal", filename);
+                       continue;;
+               }
+
+               info("removing symlink '%s'", filename);
+               unlink(filename);
+
+               if (strchr(filename, '/'))
+                       delete_path(filename);
        }
-       return retval;
-}
 
-static int delete_node(struct udevice *dev)
-{
-       char filename[NAME_SIZE];
-       char linkname[NAME_SIZE];
-       char partitionname[NAME_SIZE];
-       int retval;
-       int i;
-       char *pos;
-       int len;
+       snprintf(filename, sizeof(filename), "%s/%s", udev_root, udev->name);
+       filename[sizeof(filename)-1] = '\0';
 
-       strfieldcpy(filename, udev_root);
-       strfieldcat(filename, dev->name);
+       if (stat(filename, &stats) != 0) {
+               dbg("device node '%s' not found", filename);
+               return -1;
+       }
+       if (udev->devt && stats.st_rdev != udev->devt) {
+               info("device node '%s' points to a different device, skip removal", filename);
+               return -1;
+       }
 
        info("removing device node '%s'", filename);
-       retval = secure_unlink(filename);
+       retval = unlink_secure(filename);
        if (retval)
                return retval;
 
-       /* remove partition nodes */
-       if (dev->partitions > 0) {
-               info("removing partitions '%s[1-%i]'", filename, dev->partitions);
-               for (i = 1; i <= dev->partitions; i++) {
-                       strfieldcpy(partitionname, filename);
-                       strintcat(partitionname, i);
-                       secure_unlink(partitionname);
+       num = udev->partitions;
+       if (num > 0) {
+               info("removing all_partitions '%s[1-%i]'", filename, num);
+               if (num > 255) {
+                       info("garbage from udev database, skip all_partitions removal");
+                       return -1;
+               }
+               for (i = 1; i <= num; i++) {
+                       snprintf(partitionname, sizeof(partitionname), "%s%d", filename, i);
+                       partitionname[sizeof(partitionname)-1] = '\0';
+                       unlink_secure(partitionname);
                }
        }
 
-       /* remove subdirectories */
-       if (strchr(dev->name, '/'))
+       if (strchr(udev->name, '/'))
                delete_path(filename);
 
-       foreach_strpart(dev->symlink, " ", pos, len) {
-               strfieldcpymax(linkname, pos, len+1);
-               strfieldcpy(filename, udev_root);
-               strfieldcat(filename, linkname);
-
-               dbg("unlinking symlink '%s'", filename);
-               retval = unlink(filename);
-               if (errno == ENOENT)
-                       retval = 0;
-               if (retval) {
-                       dbg("unlink(%s) failed with error '%s'",
-                               filename, strerror(errno));
-                       return retval;
-               }
-               if (strchr(dev->symlink, '/')) {
-                       delete_path(filename);
-               }
-       }
-
        return retval;
 }
 
 /*
- * Look up the sysfs path in the database to see if we have named this device
- * something different from the kernel name.  If we have, us it.  If not, use
- * the default kernel name for lack of anything else to know to do.
+ * look up the sysfs path in the database to get the node name to remove
+ * If we can't find it, use kernel name for lack of anything else to know to do
  */
-int udev_remove_device(const char *path, const char *subsystem)
+int udev_remove_device(struct udevice *udev)
 {
-       struct udevice dev;
-       char *temp;
-       int retval;
-
-       memset(&dev, 0x00, sizeof(dev));
+       if (udev->type != DEV_BLOCK && udev->type != DEV_CLASS)
+               return 0;
 
-       retval = udevdb_get_dev(path, &dev);
-       if (retval != 0) {
-               dbg("'%s' not found in database, falling back on default name", path);
-               temp = strrchr(path, '/');
-               if (temp == NULL)
-                       return -ENODEV;
-               strfieldcpy(dev.name, &temp[1]);
+       if (udev_db_get_device(udev, udev->devpath) == 0) {
+               if (udev->ignore_remove) {
+                       dbg("remove event for '%s' requested to be ignored by rule", udev->name);
+                       return 0;
+               }
+               dbg("remove name='%s'", udev->name);
+               udev_db_delete_device(udev);
+       } else {
+               dbg("'%s' not found in database, using kernel name '%s'", udev->devpath, udev->kernel_name);
+               strlcpy(udev->name, udev->kernel_name, sizeof(udev->name));
        }
-       dbg("name='%s'", dev.name);
-
-       dev.type = get_device_type(path, subsystem);
-       dev_d_send(&dev, subsystem, path);
-       udevdb_delete_dev(path);
+       /* use full path to the environment */
+       snprintf(udev->devname, sizeof(udev->devname), "%s/%s", udev_root, udev->name);
+       udev->devname[sizeof(udev->devname)-1] = '\0';
 
-       if (dev.type == 'b' || dev.type == 'c')
-               retval = delete_node(&dev);
-       else if (dev.type == 'n')
-               retval = 0;
-
-       return retval;
+       return delete_node(udev);
 }