[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) {
        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(NULL, 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	116	DIR *dir;
8fb3f009	117	struct dirent *dent;
912541b0 KS	118	int priority = 0;
	119	const char *target = NULL;
	120
	121	if (add) {
	122	priority = udev_device_get_devlink_priority(dev);
d5a89d7d	123	strscpy(buf, bufsize, udev_device_get_devnode(dev));
912541b0 KS	124	target = buf;
	125	}
	126
	127	dir = opendir(stackdir);
	128	if (dir == NULL)
	129	return target;
8fb3f009	130	FOREACH_DIRENT_ALL(dent, dir, break) {
912541b0	131	struct udev_device *dev_db;
912541b0	132
8fb3f009	133	if (dent->d_name[0] == '\0')
912541b0 KS	134	break;
	135	if (dent->d_name[0] == '.')
	136	continue;
	137
9f6445e3	138	log_debug("found '%s' claiming '%s'", dent->d_name, stackdir);
912541b0 KS	139
912541b0 KS	140	/* did we find ourself? */
090be865	141	if (streq(dent->d_name, udev_device_get_id_filename(dev)))
912541b0 KS	142	continue;
912541b0 KS	143
2024ed61	144	dev_db = udev_device_new_from_device_id(NULL, dent->d_name);
912541b0 KS	145	if (dev_db != NULL) {
	146	const char *devnode;
	147
	148	devnode = udev_device_get_devnode(dev_db);
	149	if (devnode != NULL) {
912541b0	150	if (target == NULL \|\| udev_device_get_devlink_priority(dev_db) > priority) {
9f6445e3	151	log_debug("'%s' claims priority %i for '%s'",
baa30fbc	152	udev_device_get_syspath(dev_db), udev_device_get_devlink_priority(dev_db), stackdir);
912541b0	153	priority = udev_device_get_devlink_priority(dev_db);
d5a89d7d	154	strscpy(buf, bufsize, devnode);
912541b0 KS	155	target = buf;
	156	}
	157	}
	158	udev_device_unref(dev_db);
	159	}
	160	}
	161	closedir(dir);
	162	return target;
aa8734ff KS	163	}
aa8734ff KS	164
6c29f2b9	165	/* manage "stack of names" with possibly specified device priorities */
9ec6e95b	166	static void link_update(struct udev_device dev, const char slink, bool add) {
912541b0 KS	167	char name_enc[UTIL_PATH_SIZE];
	168	char filename[UTIL_PATH_SIZE * 2];
	169	char dirname[UTIL_PATH_SIZE];
	170	const char *target;
	171	char buf[UTIL_PATH_SIZE];
	172
fbd0b64f	173	util_path_encode(slink + STRLEN("/dev"), name_enc, sizeof(name_enc));
d5a89d7d KS	174	strscpyl(dirname, sizeof(dirname), "/run/udev/links/", name_enc, NULL);
d5a89d7d KS	175	strscpyl(filename, sizeof(filename), dirname, "/", udev_device_get_id_filename(dev), NULL);
912541b0	176
baa30fbc KS	177	if (!add && unlink(filename) == 0)
baa30fbc KS	178	rmdir(dirname);
912541b0 KS	179
	180	target = link_find_prioritized(dev, add, dirname, buf, sizeof(buf));
	181	if (target == NULL) {
9f6445e3	182	log_debug("no reference left, remove '%s'", slink);
912541b0	183	if (unlink(slink) == 0)
37d52274	184	rmdir_parents(slink, "/");
912541b0	185	} else {
9f6445e3	186	log_debug("creating link '%s' to '%s'", slink, target);
38d70045	187	node_symlink(dev, target, slink);
912541b0 KS	188	}
	189
	190	if (add) {
	191	int err;
	192
912541b0 KS	193	do {
	194	int fd;
	195
3cbd5f6b	196	err = mkdir_parents(filename, 0755);
4c701096	197	if (!IN_SET(err, 0, -ENOENT))
912541b0 KS	198	break;
	199	fd = open(filename, O_WRONLY\|O_CREAT\|O_CLOEXEC\|O_TRUNC\|O_NOFOLLOW, 0444);
	200	if (fd >= 0)
	201	close(fd);
	202	else
	203	err = -errno;
	204	} while (err == -ENOENT);
	205	}
24f0605c KS	206	}
24f0605c KS	207
9ec6e95b	208	void udev_node_update_old_links(struct udev_device dev, struct udev_device dev_old) {
912541b0 KS	209	struct udev_list_entry *list_entry;
	210
	211	/* update possible left-over symlinks */
	212	udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev_old)) {
	213	const char *name = udev_list_entry_get_name(list_entry);
	214	struct udev_list_entry *list_entry_current;
	215	int found;
	216
	217	/* check if old link name still belongs to this device */
	218	found = 0;
	219	udev_list_entry_foreach(list_entry_current, udev_device_get_devlinks_list_entry(dev)) {
	220	const char *name_current = udev_list_entry_get_name(list_entry_current);
	221
090be865	222	if (streq(name, name_current)) {
912541b0 KS	223	found = 1;
	224	break;
	225	}
	226	}
	227	if (found)
	228	continue;
	229
9f6445e3	230	log_debug("update old name, '%s' no longer belonging to '%s'",
912541b0	231	name, udev_device_get_devpath(dev));
8a173387	232	link_update(dev, name, false);
912541b0	233	}
24f0605c KS	234	}
24f0605c KS	235
c26547d6 KS	236	static int node_permissions_apply(struct udev_device *dev, bool apply,
	237	mode_t mode, uid_t uid, gid_t gid,
	238	struct udev_list *seclabel_list) {
912541b0 KS	239	const char *devnode = udev_device_get_devnode(dev);
	240	dev_t devnum = udev_device_get_devnum(dev);
	241	struct stat stats;
c26547d6	242	struct udev_list_entry *entry;
912541b0 KS	243	int err = 0;
912541b0 KS	244
090be865	245	if (streq(udev_device_get_subsystem(dev), "block"))
912541b0 KS	246	mode \|= S_IFBLK;
	247	else
	248	mode \|= S_IFCHR;
	249
	250	if (lstat(devnode, &stats) != 0) {
87ac8d99	251	err = log_debug_errno(errno, "cannot stat() node '%s' (%m)", devnode);
912541b0 KS	252	goto out;
	253	}
	254
	255	if (((stats.st_mode & S_IFMT) != (mode & S_IFMT)) \|\| (stats.st_rdev != devnum)) {
	256	err = -EEXIST;
9f6445e3	257	log_debug("found node '%s' with non-matching devnum %s, skip handling",
baa30fbc	258	udev_device_get_devnode(dev), udev_device_get_id_filename(dev));
912541b0 KS	259	goto out;
	260	}
	261
22582bb2	262	if (apply) {
b7e2b764	263	bool selinux = false;
b7e2b764	264	bool smack = false;
b7e2b764	265
48a849ee	266	if ((stats.st_mode & 0777) != (mode & 0777) \|\| stats.st_uid != uid \|\| stats.st_gid != gid) {
9f6445e3	267	log_debug("set permissions %s, %#o, uid=%u, gid=%u", devnode, mode, uid, gid);
543afdc6 TG	268	err = chmod(devnode, mode);
543afdc6 TG	269	if (err < 0)
56f64d95	270	log_warning_errno(errno, "setting mode of %s to %#o failed: %m", devnode, mode);
543afdc6 TG	271	err = chown(devnode, uid, gid);
543afdc6 TG	272	if (err < 0)
56f64d95	273	log_warning_errno(errno, "setting owner of %s to uid=%u, gid=%u failed: %m", devnode, uid, gid);
48a849ee	274	} else {
9f6445e3	275	log_debug("preserve permissions %s, %#o, uid=%u, gid=%u", devnode, mode, uid, gid);
48a849ee	276	}
c26547d6	277
c26547d6 KS	278	/* apply SECLABEL{$module}=$label */
	279	udev_list_entry_foreach(entry, udev_list_get_entry(seclabel_list)) {
	280	const char name, label;
d53e386d	281	int r;
c26547d6 KS	282
	283	name = udev_list_entry_get_name(entry);
	284	label = udev_list_entry_get_value(entry);
	285
	286	if (streq(name, "selinux")) {
b7e2b764	287	selinux = true;
d53e386d	288
ecabcf8b LP	289	r = mac_selinux_apply(devnode, label);
ecabcf8b LP	290	if (r < 0)
da927ba9	291	log_error_errno(r, "SECLABEL: failed to set SELinux label '%s': %m", label);
463b5dbb KS	292	else
463b5dbb KS	293	log_debug("SECLABEL: set SELinux label '%s'", label);
c26547d6	294
9a4e038c	295	} else if (streq(name, "smack")) {
b7e2b764	296	smack = true;
d53e386d	297
5ab58c20	298	r = mac_smack_apply(devnode, SMACK_ATTR_ACCESS, label);
d53e386d	299	if (r < 0)
da927ba9	300	log_error_errno(r, "SECLABEL: failed to set SMACK label '%s': %m", label);
c26547d6 KS	301	else
c26547d6 KS	302	log_debug("SECLABEL: set SMACK label '%s'", label);
c26547d6 KS	303
	304	} else
	305	log_error("SECLABEL: unknown subsystem, ignoring '%s'='%s'", name, label);
	306	}
b7e2b764 KS	307
	308	/* set the defaults */
	309	if (!selinux)
08c84981	310	(void) mac_selinux_fix(devnode, LABEL_IGNORE_ENOENT);
9a4e038c	311	if (!smack)
5ab58c20	312	mac_smack_apply(devnode, SMACK_ATTR_ACCESS, NULL);
48a849ee	313	}
912541b0 KS	314
	315	/* always update timestamp when we re-use the node, like on media change events */
	316	utimensat(AT_FDCWD, devnode, NULL, 0);
220893b3	317	out:
912541b0	318	return err;
220893b3 KS	319	}
220893b3 KS	320
c26547d6 KS	321	void udev_node_add(struct udev_device *dev, bool apply,
	322	mode_t mode, uid_t uid, gid_t gid,
	323	struct udev_list *seclabel_list) {
c67f84b0	324	char filename[DEV_NUM_PATH_MAX];
912541b0	325	struct udev_list_entry *list_entry;
912541b0	326
1fa2f38f	327	log_debug("handling device node '%s', devnum=%s, mode=%#o, uid="UID_FMT", gid="GID_FMT,
baa30fbc	328	udev_device_get_devnode(dev), udev_device_get_id_filename(dev), mode, uid, gid);
912541b0	329
c26547d6	330	if (node_permissions_apply(dev, apply, mode, uid, gid, seclabel_list) < 0)
e7f32890	331	return;
912541b0 KS	332
912541b0 KS	333	/* always add /dev/{block,char}/$major:$minor */
c67f84b0 ZJS	334	xsprintf_dev_num_path(filename,
	335	streq(udev_device_get_subsystem(dev), "block") ? "block" : "char",
	336	udev_device_get_devnum(dev));
38d70045	337	node_symlink(dev, udev_device_get_devnode(dev), filename);
912541b0 KS	338
912541b0 KS	339	/* create/update symlinks, add symlinks to name index */
8a173387 KS	340	udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev))
8a173387 KS	341	link_update(dev, udev_list_entry_get_name(list_entry), true);
ea733a2f GKH	342	}
ea733a2f GKH	343
9ec6e95b	344	void udev_node_remove(struct udev_device *dev) {
912541b0	345	struct udev_list_entry *list_entry;
c67f84b0	346	char filename[DEV_NUM_PATH_MAX];
912541b0 KS	347
	348	/* remove/update symlinks, remove symlinks from name index */
	349	udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev))
8a173387	350	link_update(dev, udev_list_entry_get_name(list_entry), false);
912541b0 KS	351
912541b0 KS	352	/* remove /dev/{block,char}/$major:$minor */
c67f84b0 ZJS	353	xsprintf_dev_num_path(filename,
	354	streq(udev_device_get_subsystem(dev), "block") ? "block" : "char",
	355	udev_device_get_devnum(dev));
912541b0	356	unlink(filename);
ea733a2f	357	}