[thirdparty/systemd.git] / src / udev / udev-node.c

/* SPDX-License-Identifier: GPL-2.0+ */

#include <errno.h>
#include <fcntl.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>

#include "device-nodes.h"
#include "dirent-util.h"
#include "format-util.h"
#include "fs-util.h"
#include "selinux-util.h"
#include "smack-util.h"
#include "stdio-util.h"
#include "string-util.h"
#include "udev.h"

static int node_symlink(struct udev_device *dev, const char *node, const char *slink) {
        struct stat stats;
        char target[UTIL_PATH_SIZE];
        char *s;
        size_t l;
        char slink_tmp[UTIL_PATH_SIZE + 32];
        int i = 0;
        int tail = 0;
        int err = 0;

        /* use relative link */
        target[0] = '\0';
        while (node[i] && (node[i] == slink[i])) {
                if (node[i] == '/')
                        tail = i+1;
                i++;
        }
        s = target;
        l = sizeof(target);
        while (slink[i] != '\0') {
                if (slink[i] == '/')
                        l = strpcpy(&s, l, "../");
                i++;
        }
        l = strscpy(s, l, &node[tail]);
        if (l == 0) {
                err = -EINVAL;
                goto exit;
        }

        /* preserve link with correct target, do not replace node of other device */
        if (lstat(slink, &stats) == 0) {
                if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
                        log_error("conflicting device node '%s' found, link to '%s' will not be created", slink, node);
                        goto exit;
                } else if (S_ISLNK(stats.st_mode)) {
                        char buf[UTIL_PATH_SIZE];
                        int len;

                        len = readlink(slink, buf, sizeof(buf));
                        if (len > 0 && len < (int)sizeof(buf)) {
                                buf[len] = '\0';
                                if (streq(target, buf)) {
                                        log_debug("preserve already existing symlink '%s' to '%s'", slink, target);
                                        (void) label_fix(slink, LABEL_IGNORE_ENOENT);
                                        utimensat(AT_FDCWD, slink, NULL, AT_SYMLINK_NOFOLLOW);
                                        goto exit;
                                }
                        }
                }
        } else {
                log_debug("creating symlink '%s' to '%s'", slink, target);
                do {
                        err = mkdir_parents_label(slink, 0755);
                        if (!IN_SET(err, 0, -ENOENT))
                                break;
                        mac_selinux_create_file_prepare(slink, S_IFLNK);
                        err = symlink(target, slink);
                        if (err != 0)
                                err = -errno;
                        mac_selinux_create_file_clear();
                } while (err == -ENOENT);
                if (err == 0)
                        goto exit;
        }

        log_debug("atomically replace '%s'", slink);
        strscpyl(slink_tmp, sizeof(slink_tmp), slink, ".tmp-", udev_device_get_id_filename(dev), NULL);
        unlink(slink_tmp);
        do {
                err = mkdir_parents_label(slink_tmp, 0755);
                if (!IN_SET(err, 0, -ENOENT))
                        break;
                mac_selinux_create_file_prepare(slink_tmp, S_IFLNK);
                err = symlink(target, slink_tmp);
                if (err != 0)
                        err = -errno;
                mac_selinux_create_file_clear();
        } while (err == -ENOENT);
        if (err != 0) {
                log_error_errno(errno, "symlink '%s' '%s' failed: %m", target, slink_tmp);
                goto exit;
        }
        err = rename(slink_tmp, slink);
        if (err != 0) {
                log_error_errno(errno, "rename '%s' '%s' failed: %m", slink_tmp, slink);
                unlink(slink_tmp);
        }
exit:
        return err;
}

/* find device node of device with highest priority */
static const char *link_find_prioritized(struct udev_device *dev, bool add, const char *stackdir, char *buf, size_t bufsize) {
        struct udev *udev = udev_device_get_udev(dev);
        DIR *dir;
        struct dirent *dent;
        int priority = 0;
        const char *target = NULL;

        if (add) {
                priority = udev_device_get_devlink_priority(dev);
                strscpy(buf, bufsize, udev_device_get_devnode(dev));
                target = buf;
        }

        dir = opendir(stackdir);
        if (dir == NULL)
                return target;
        FOREACH_DIRENT_ALL(dent, dir, break) {
                struct udev_device *dev_db;

                if (dent->d_name[0] == '\0')
                        break;
                if (dent->d_name[0] == '.')
                        continue;

                log_debug("found '%s' claiming '%s'", dent->d_name, stackdir);

                /* did we find ourself? */
                if (streq(dent->d_name, udev_device_get_id_filename(dev)))
                        continue;

                dev_db = udev_device_new_from_device_id(udev, dent->d_name);
                if (dev_db != NULL) {
                        const char *devnode;

                        devnode = udev_device_get_devnode(dev_db);
                        if (devnode != NULL) {
                                if (target == NULL || udev_device_get_devlink_priority(dev_db) > priority) {
                                        log_debug("'%s' claims priority %i for '%s'",
                                                  udev_device_get_syspath(dev_db), udev_device_get_devlink_priority(dev_db), stackdir);
                                        priority = udev_device_get_devlink_priority(dev_db);
                                        strscpy(buf, bufsize, devnode);
                                        target = buf;
                                }
                        }
                        udev_device_unref(dev_db);
                }
        }
        closedir(dir);
        return target;
}

/* manage "stack of names" with possibly specified device priorities */
static void link_update(struct udev_device *dev, const char *slink, bool add) {
        char name_enc[UTIL_PATH_SIZE];
        char filename[UTIL_PATH_SIZE * 2];
        char dirname[UTIL_PATH_SIZE];
        const char *target;
        char buf[UTIL_PATH_SIZE];

        util_path_encode(slink + STRLEN("/dev"), name_enc, sizeof(name_enc));
        strscpyl(dirname, sizeof(dirname), "/run/udev/links/", name_enc, NULL);
        strscpyl(filename, sizeof(filename), dirname, "/", udev_device_get_id_filename(dev), NULL);

        if (!add && unlink(filename) == 0)
                rmdir(dirname);

        target = link_find_prioritized(dev, add, dirname, buf, sizeof(buf));
        if (target == NULL) {
                log_debug("no reference left, remove '%s'", slink);
                if (unlink(slink) == 0)
                        rmdir_parents(slink, "/");
        } else {
                log_debug("creating link '%s' to '%s'", slink, target);
                node_symlink(dev, target, slink);
        }

        if (add) {
                int err;

                do {
                        int fd;

                        err = mkdir_parents(filename, 0755);
                        if (!IN_SET(err, 0, -ENOENT))
                                break;
                        fd = open(filename, O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444);
                        if (fd >= 0)
                                close(fd);
                        else
                                err = -errno;
                } while (err == -ENOENT);
        }
}

void udev_node_update_old_links(struct udev_device *dev, struct udev_device *dev_old) {
        struct udev_list_entry *list_entry;

        /* update possible left-over symlinks */
        udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev_old)) {
                const char *name = udev_list_entry_get_name(list_entry);
                struct udev_list_entry *list_entry_current;
                int found;

                /* check if old link name still belongs to this device */
                found = 0;
                udev_list_entry_foreach(list_entry_current, udev_device_get_devlinks_list_entry(dev)) {
                        const char *name_current = udev_list_entry_get_name(list_entry_current);

                        if (streq(name, name_current)) {
                                found = 1;
                                break;
                        }
                }
                if (found)
                        continue;

                log_debug("update old name, '%s' no longer belonging to '%s'",
                     name, udev_device_get_devpath(dev));
                link_update(dev, name, false);
        }
}

static int node_permissions_apply(struct udev_device *dev, bool apply,
                                  mode_t mode, uid_t uid, gid_t gid,
                                  struct udev_list *seclabel_list) {
        const char *devnode = udev_device_get_devnode(dev);
        dev_t devnum = udev_device_get_devnum(dev);
        struct stat stats;
        struct udev_list_entry *entry;
        int err = 0;

        if (streq(udev_device_get_subsystem(dev), "block"))
                mode |= S_IFBLK;
        else
                mode |= S_IFCHR;

        if (lstat(devnode, &stats) != 0) {
                err = log_debug_errno(errno, "cannot stat() node '%s' (%m)", devnode);
                goto out;
        }

        if (((stats.st_mode & S_IFMT) != (mode & S_IFMT)) || (stats.st_rdev != devnum)) {
                err = -EEXIST;
                log_debug("found node '%s' with non-matching devnum %s, skip handling",
                          udev_device_get_devnode(dev), udev_device_get_id_filename(dev));
                goto out;
        }

        if (apply) {
                bool selinux = false;
                bool smack = false;

                if ((stats.st_mode & 0777) != (mode & 0777) || stats.st_uid != uid || stats.st_gid != gid) {
                        log_debug("set permissions %s, %#o, uid=%u, gid=%u", devnode, mode, uid, gid);
                        err = chmod(devnode, mode);
                        if (err < 0)
                                log_warning_errno(errno, "setting mode of %s to %#o failed: %m", devnode, mode);
                        err = chown(devnode, uid, gid);
                        if (err < 0)
                                log_warning_errno(errno, "setting owner of %s to uid=%u, gid=%u failed: %m", devnode, uid, gid);
                } else {
                        log_debug("preserve permissions %s, %#o, uid=%u, gid=%u", devnode, mode, uid, gid);
                }

                /* apply SECLABEL{$module}=$label */
                udev_list_entry_foreach(entry, udev_list_get_entry(seclabel_list)) {
                        const char *name, *label;
                        int r;

                        name = udev_list_entry_get_name(entry);
                        label = udev_list_entry_get_value(entry);

                        if (streq(name, "selinux")) {
                                selinux = true;

                                r = mac_selinux_apply(devnode, label);
                                if (r < 0)
                                        log_error_errno(r, "SECLABEL: failed to set SELinux label '%s': %m", label);
                                else
                                        log_debug("SECLABEL: set SELinux label '%s'", label);

                        } else if (streq(name, "smack")) {
                                smack = true;

                                r = mac_smack_apply(devnode, SMACK_ATTR_ACCESS, label);
                                if (r < 0)
                                        log_error_errno(r, "SECLABEL: failed to set SMACK label '%s': %m", label);
                                else
                                        log_debug("SECLABEL: set SMACK label '%s'", label);

                        } else
                                log_error("SECLABEL: unknown subsystem, ignoring '%s'='%s'", name, label);
                }

                /* set the defaults */
                if (!selinux)
                        (void) mac_selinux_fix(devnode, LABEL_IGNORE_ENOENT);
                if (!smack)
                        mac_smack_apply(devnode, SMACK_ATTR_ACCESS, NULL);
        }

        /* always update timestamp when we re-use the node, like on media change events */
        utimensat(AT_FDCWD, devnode, NULL, 0);
out:
        return err;
}

void udev_node_add(struct udev_device *dev, bool apply,
                   mode_t mode, uid_t uid, gid_t gid,
                   struct udev_list *seclabel_list) {
        char filename[DEV_NUM_PATH_MAX];
        struct udev_list_entry *list_entry;

        log_debug("handling device node '%s', devnum=%s, mode=%#o, uid="UID_FMT", gid="GID_FMT,
                  udev_device_get_devnode(dev), udev_device_get_id_filename(dev), mode, uid, gid);

        if (node_permissions_apply(dev, apply, mode, uid, gid, seclabel_list) < 0)
                return;

        /* always add /dev/{block,char}/$major:$minor */
        xsprintf_dev_num_path(filename,
                              streq(udev_device_get_subsystem(dev), "block") ? "block" : "char",
                              udev_device_get_devnum(dev));
        node_symlink(dev, udev_device_get_devnode(dev), filename);

        /* create/update symlinks, add symlinks to name index */
        udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev))
                        link_update(dev, udev_list_entry_get_name(list_entry), true);
}

void udev_node_remove(struct udev_device *dev) {
        struct udev_list_entry *list_entry;
        char filename[DEV_NUM_PATH_MAX];

        /* remove/update symlinks, remove symlinks from name index */
        udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev))
                link_update(dev, udev_list_entry_get_name(list_entry), false);

        /* remove /dev/{block,char}/$major:$minor */
        xsprintf_dev_num_path(filename,
                              streq(udev_device_get_subsystem(dev), "block") ? "block" : "char",
                              udev_device_get_devnum(dev));
        unlink(filename);
}
Commit	Line	Data
e7145211	1	/* SPDX-License-Identifier: GPL-2.0+ */
ea733a2f	2
07630cea LP	3	#include <errno.h>
	4	#include <fcntl.h>
	5	#include <stdbool.h>
	6	#include <stddef.h>
	7	#include <stdio.h>
	8	#include <string.h>
32ff5bca	9	#include <sys/stat.h>
07630cea	10	#include <unistd.h>
ea733a2f	11
c67f84b0	12	#include "device-nodes.h"
8fb3f009	13	#include "dirent-util.h"
f97b34a6	14	#include "format-util.h"
f4f15635	15	#include "fs-util.h"
07630cea LP	16	#include "selinux-util.h"
07630cea LP	17	#include "smack-util.h"
d054f0a4	18	#include "stdio-util.h"
07630cea LP	19	#include "string-util.h"
07630cea LP	20	#include "udev.h"
9825617b	21
9ec6e95b	22	static int node_symlink(struct udev_device dev, const char node, const char *slink) {
912541b0 KS	23	struct stat stats;
	24	char target[UTIL_PATH_SIZE];
	25	char *s;
	26	size_t l;
38d70045	27	char slink_tmp[UTIL_PATH_SIZE + 32];
912541b0 KS	28	int i = 0;
	29	int tail = 0;
	30	int err = 0;
	31
	32	/* use relative link */
	33	target[0] = '\0';
	34	while (node[i] && (node[i] == slink[i])) {
	35	if (node[i] == '/')
	36	tail = i+1;
	37	i++;
	38	}
	39	s = target;
	40	l = sizeof(target);
	41	while (slink[i] != '\0') {
	42	if (slink[i] == '/')
d5a89d7d	43	l = strpcpy(&s, l, "../");
912541b0 KS	44	i++;
912541b0 KS	45	}
d5a89d7d	46	l = strscpy(s, l, &node[tail]);
912541b0 KS	47	if (l == 0) {
	48	err = -EINVAL;
	49	goto exit;
	50	}
	51
	52	/* preserve link with correct target, do not replace node of other device */
	53	if (lstat(slink, &stats) == 0) {
	54	if (S_ISBLK(stats.st_mode) \|\| S_ISCHR(stats.st_mode)) {
9f6445e3	55	log_error("conflicting device node '%s' found, link to '%s' will not be created", slink, node);
2be7287b	56	goto exit;
912541b0 KS	57	} else if (S_ISLNK(stats.st_mode)) {
	58	char buf[UTIL_PATH_SIZE];
	59	int len;
	60
912541b0 KS	61	len = readlink(slink, buf, sizeof(buf));
	62	if (len > 0 && len < (int)sizeof(buf)) {
	63	buf[len] = '\0';
090be865	64	if (streq(target, buf)) {
9f6445e3	65	log_debug("preserve already existing symlink '%s' to '%s'", slink, target);
08c84981	66	(void) label_fix(slink, LABEL_IGNORE_ENOENT);
912541b0 KS	67	utimensat(AT_FDCWD, slink, NULL, AT_SYMLINK_NOFOLLOW);
	68	goto exit;
	69	}
	70	}
	71	}
	72	} else {
9f6445e3	73	log_debug("creating symlink '%s' to '%s'", slink, target);
912541b0	74	do {
d2e54fae	75	err = mkdir_parents_label(slink, 0755);
4c701096	76	if (!IN_SET(err, 0, -ENOENT))
912541b0	77	break;
ecabcf8b	78	mac_selinux_create_file_prepare(slink, S_IFLNK);
912541b0 KS	79	err = symlink(target, slink);
	80	if (err != 0)
	81	err = -errno;
ecabcf8b	82	mac_selinux_create_file_clear();
912541b0 KS	83	} while (err == -ENOENT);
	84	if (err == 0)
	85	goto exit;
	86	}
	87
9f6445e3	88	log_debug("atomically replace '%s'", slink);
38d70045	89	strscpyl(slink_tmp, sizeof(slink_tmp), slink, ".tmp-", udev_device_get_id_filename(dev), NULL);
912541b0 KS	90	unlink(slink_tmp);
912541b0 KS	91	do {
d2e54fae	92	err = mkdir_parents_label(slink_tmp, 0755);
4c701096	93	if (!IN_SET(err, 0, -ENOENT))
912541b0	94	break;
ecabcf8b	95	mac_selinux_create_file_prepare(slink_tmp, S_IFLNK);
912541b0 KS	96	err = symlink(target, slink_tmp);
	97	if (err != 0)
	98	err = -errno;
ecabcf8b	99	mac_selinux_create_file_clear();
912541b0 KS	100	} while (err == -ENOENT);
912541b0 KS	101	if (err != 0) {
56f64d95	102	log_error_errno(errno, "symlink '%s' '%s' failed: %m", target, slink_tmp);
912541b0 KS	103	goto exit;
	104	}
	105	err = rename(slink_tmp, slink);
	106	if (err != 0) {
56f64d95	107	log_error_errno(errno, "rename '%s' '%s' failed: %m", slink_tmp, slink);
912541b0 KS	108	unlink(slink_tmp);
912541b0 KS	109	}
fa33d857	110	exit:
912541b0	111	return err;
fa33d857 KS	112	}
fa33d857 KS	113
6c29f2b9	114	/* find device node of device with highest priority */
9ec6e95b	115	static const char link_find_prioritized(struct udev_device dev, bool add, const char stackdir, char buf, size_t bufsize) {
912541b0 KS	116	struct udev *udev = udev_device_get_udev(dev);
912541b0 KS	117	DIR *dir;
8fb3f009	118	struct dirent *dent;
912541b0 KS	119	int priority = 0;
	120	const char *target = NULL;
	121
	122	if (add) {
	123	priority = udev_device_get_devlink_priority(dev);
d5a89d7d	124	strscpy(buf, bufsize, udev_device_get_devnode(dev));
912541b0 KS	125	target = buf;
	126	}
	127
	128	dir = opendir(stackdir);
	129	if (dir == NULL)
	130	return target;
8fb3f009	131	FOREACH_DIRENT_ALL(dent, dir, break) {
912541b0	132	struct udev_device *dev_db;
912541b0	133
8fb3f009	134	if (dent->d_name[0] == '\0')
912541b0 KS	135	break;
	136	if (dent->d_name[0] == '.')
	137	continue;
	138
9f6445e3	139	log_debug("found '%s' claiming '%s'", dent->d_name, stackdir);
912541b0 KS	140
912541b0 KS	141	/* did we find ourself? */
090be865	142	if (streq(dent->d_name, udev_device_get_id_filename(dev)))
912541b0 KS	143	continue;
912541b0 KS	144
dbf61afb	145	dev_db = udev_device_new_from_device_id(udev, dent->d_name);
912541b0 KS	146	if (dev_db != NULL) {
	147	const char *devnode;
	148
	149	devnode = udev_device_get_devnode(dev_db);
	150	if (devnode != NULL) {
912541b0	151	if (target == NULL \|\| udev_device_get_devlink_priority(dev_db) > priority) {
9f6445e3	152	log_debug("'%s' claims priority %i for '%s'",
baa30fbc	153	udev_device_get_syspath(dev_db), udev_device_get_devlink_priority(dev_db), stackdir);
912541b0	154	priority = udev_device_get_devlink_priority(dev_db);
d5a89d7d	155	strscpy(buf, bufsize, devnode);
912541b0 KS	156	target = buf;
	157	}
	158	}
	159	udev_device_unref(dev_db);
	160	}
	161	}
	162	closedir(dir);
	163	return target;
aa8734ff KS	164	}
aa8734ff KS	165
6c29f2b9	166	/* manage "stack of names" with possibly specified device priorities */
9ec6e95b	167	static void link_update(struct udev_device dev, const char slink, bool add) {
912541b0 KS	168	char name_enc[UTIL_PATH_SIZE];
	169	char filename[UTIL_PATH_SIZE * 2];
	170	char dirname[UTIL_PATH_SIZE];
	171	const char *target;
	172	char buf[UTIL_PATH_SIZE];
	173
fbd0b64f	174	util_path_encode(slink + STRLEN("/dev"), name_enc, sizeof(name_enc));
d5a89d7d KS	175	strscpyl(dirname, sizeof(dirname), "/run/udev/links/", name_enc, NULL);
d5a89d7d KS	176	strscpyl(filename, sizeof(filename), dirname, "/", udev_device_get_id_filename(dev), NULL);
912541b0	177
baa30fbc KS	178	if (!add && unlink(filename) == 0)
baa30fbc KS	179	rmdir(dirname);
912541b0 KS	180
	181	target = link_find_prioritized(dev, add, dirname, buf, sizeof(buf));
	182	if (target == NULL) {
9f6445e3	183	log_debug("no reference left, remove '%s'", slink);
912541b0	184	if (unlink(slink) == 0)
37d52274	185	rmdir_parents(slink, "/");
912541b0	186	} else {
9f6445e3	187	log_debug("creating link '%s' to '%s'", slink, target);
38d70045	188	node_symlink(dev, target, slink);
912541b0 KS	189	}
	190
	191	if (add) {
	192	int err;
	193
912541b0 KS	194	do {
	195	int fd;
	196
3cbd5f6b	197	err = mkdir_parents(filename, 0755);
4c701096	198	if (!IN_SET(err, 0, -ENOENT))
912541b0 KS	199	break;
	200	fd = open(filename, O_WRONLY\|O_CREAT\|O_CLOEXEC\|O_TRUNC\|O_NOFOLLOW, 0444);
	201	if (fd >= 0)
	202	close(fd);
	203	else
	204	err = -errno;
	205	} while (err == -ENOENT);
	206	}
24f0605c KS	207	}
24f0605c KS	208
9ec6e95b	209	void udev_node_update_old_links(struct udev_device dev, struct udev_device dev_old) {
912541b0 KS	210	struct udev_list_entry *list_entry;
	211
	212	/* update possible left-over symlinks */
	213	udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev_old)) {
	214	const char *name = udev_list_entry_get_name(list_entry);
	215	struct udev_list_entry *list_entry_current;
	216	int found;
	217
	218	/* check if old link name still belongs to this device */
	219	found = 0;
	220	udev_list_entry_foreach(list_entry_current, udev_device_get_devlinks_list_entry(dev)) {
	221	const char *name_current = udev_list_entry_get_name(list_entry_current);
	222
090be865	223	if (streq(name, name_current)) {
912541b0 KS	224	found = 1;
	225	break;
	226	}
	227	}
	228	if (found)
	229	continue;
	230
9f6445e3	231	log_debug("update old name, '%s' no longer belonging to '%s'",
912541b0	232	name, udev_device_get_devpath(dev));
8a173387	233	link_update(dev, name, false);
912541b0	234	}
24f0605c KS	235	}
24f0605c KS	236
c26547d6 KS	237	static int node_permissions_apply(struct udev_device *dev, bool apply,
	238	mode_t mode, uid_t uid, gid_t gid,
	239	struct udev_list *seclabel_list) {
912541b0 KS	240	const char *devnode = udev_device_get_devnode(dev);
	241	dev_t devnum = udev_device_get_devnum(dev);
	242	struct stat stats;
c26547d6	243	struct udev_list_entry *entry;
912541b0 KS	244	int err = 0;
912541b0 KS	245
090be865	246	if (streq(udev_device_get_subsystem(dev), "block"))
912541b0 KS	247	mode \|= S_IFBLK;
	248	else
	249	mode \|= S_IFCHR;
	250
	251	if (lstat(devnode, &stats) != 0) {
87ac8d99	252	err = log_debug_errno(errno, "cannot stat() node '%s' (%m)", devnode);
912541b0 KS	253	goto out;
	254	}
	255
	256	if (((stats.st_mode & S_IFMT) != (mode & S_IFMT)) \|\| (stats.st_rdev != devnum)) {
	257	err = -EEXIST;
9f6445e3	258	log_debug("found node '%s' with non-matching devnum %s, skip handling",
baa30fbc	259	udev_device_get_devnode(dev), udev_device_get_id_filename(dev));
912541b0 KS	260	goto out;
	261	}
	262
22582bb2	263	if (apply) {
b7e2b764	264	bool selinux = false;
b7e2b764	265	bool smack = false;
b7e2b764	266
48a849ee	267	if ((stats.st_mode & 0777) != (mode & 0777) \|\| stats.st_uid != uid \|\| stats.st_gid != gid) {
9f6445e3	268	log_debug("set permissions %s, %#o, uid=%u, gid=%u", devnode, mode, uid, gid);
543afdc6 TG	269	err = chmod(devnode, mode);
543afdc6 TG	270	if (err < 0)
56f64d95	271	log_warning_errno(errno, "setting mode of %s to %#o failed: %m", devnode, mode);
543afdc6 TG	272	err = chown(devnode, uid, gid);
543afdc6 TG	273	if (err < 0)
56f64d95	274	log_warning_errno(errno, "setting owner of %s to uid=%u, gid=%u failed: %m", devnode, uid, gid);
48a849ee	275	} else {
9f6445e3	276	log_debug("preserve permissions %s, %#o, uid=%u, gid=%u", devnode, mode, uid, gid);
48a849ee	277	}
c26547d6	278
c26547d6 KS	279	/* apply SECLABEL{$module}=$label */
	280	udev_list_entry_foreach(entry, udev_list_get_entry(seclabel_list)) {
	281	const char name, label;
d53e386d	282	int r;
c26547d6 KS	283
	284	name = udev_list_entry_get_name(entry);
	285	label = udev_list_entry_get_value(entry);
	286
	287	if (streq(name, "selinux")) {
b7e2b764	288	selinux = true;
d53e386d	289
ecabcf8b LP	290	r = mac_selinux_apply(devnode, label);
ecabcf8b LP	291	if (r < 0)
da927ba9	292	log_error_errno(r, "SECLABEL: failed to set SELinux label '%s': %m", label);
463b5dbb KS	293	else
463b5dbb KS	294	log_debug("SECLABEL: set SELinux label '%s'", label);
c26547d6	295
9a4e038c	296	} else if (streq(name, "smack")) {
b7e2b764	297	smack = true;
d53e386d	298
5ab58c20	299	r = mac_smack_apply(devnode, SMACK_ATTR_ACCESS, label);
d53e386d	300	if (r < 0)
da927ba9	301	log_error_errno(r, "SECLABEL: failed to set SMACK label '%s': %m", label);
c26547d6 KS	302	else
c26547d6 KS	303	log_debug("SECLABEL: set SMACK label '%s'", label);
c26547d6 KS	304
	305	} else
	306	log_error("SECLABEL: unknown subsystem, ignoring '%s'='%s'", name, label);
	307	}
b7e2b764 KS	308
	309	/* set the defaults */
	310	if (!selinux)
08c84981	311	(void) mac_selinux_fix(devnode, LABEL_IGNORE_ENOENT);
9a4e038c	312	if (!smack)
5ab58c20	313	mac_smack_apply(devnode, SMACK_ATTR_ACCESS, NULL);
48a849ee	314	}
912541b0 KS	315
	316	/* always update timestamp when we re-use the node, like on media change events */
	317	utimensat(AT_FDCWD, devnode, NULL, 0);
220893b3	318	out:
912541b0	319	return err;
220893b3 KS	320	}
220893b3 KS	321
c26547d6 KS	322	void udev_node_add(struct udev_device *dev, bool apply,
	323	mode_t mode, uid_t uid, gid_t gid,
	324	struct udev_list *seclabel_list) {
c67f84b0	325	char filename[DEV_NUM_PATH_MAX];
912541b0	326	struct udev_list_entry *list_entry;
912541b0	327
1fa2f38f	328	log_debug("handling device node '%s', devnum=%s, mode=%#o, uid="UID_FMT", gid="GID_FMT,
baa30fbc	329	udev_device_get_devnode(dev), udev_device_get_id_filename(dev), mode, uid, gid);
912541b0	330
c26547d6	331	if (node_permissions_apply(dev, apply, mode, uid, gid, seclabel_list) < 0)
e7f32890	332	return;
912541b0 KS	333
912541b0 KS	334	/* always add /dev/{block,char}/$major:$minor */
c67f84b0 ZJS	335	xsprintf_dev_num_path(filename,
	336	streq(udev_device_get_subsystem(dev), "block") ? "block" : "char",
	337	udev_device_get_devnum(dev));
38d70045	338	node_symlink(dev, udev_device_get_devnode(dev), filename);
912541b0 KS	339
912541b0 KS	340	/* create/update symlinks, add symlinks to name index */
8a173387 KS	341	udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev))
8a173387 KS	342	link_update(dev, udev_list_entry_get_name(list_entry), true);
ea733a2f GKH	343	}
ea733a2f GKH	344
9ec6e95b	345	void udev_node_remove(struct udev_device *dev) {
912541b0	346	struct udev_list_entry *list_entry;
c67f84b0	347	char filename[DEV_NUM_PATH_MAX];
912541b0 KS	348
	349	/* remove/update symlinks, remove symlinks from name index */
	350	udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev))
8a173387	351	link_update(dev, udev_list_entry_get_name(list_entry), false);
912541b0 KS	352
912541b0 KS	353	/* remove /dev/{block,char}/$major:$minor */
c67f84b0 ZJS	354	xsprintf_dev_num_path(filename,
	355	streq(udev_device_get_subsystem(dev), "block") ? "block" : "char",
	356	udev_device_get_devnum(dev));
912541b0	357	unlink(filename);
ea733a2f	358	}