257 lines
7.2 KiB
C
257 lines
7.2 KiB
C
/* SPDX-License-Identifier: LGPL-2.1-or-later */
|
|
|
|
#include <errno.h>
|
|
|
|
#include "sd-device.h"
|
|
|
|
#include "acl-util.h"
|
|
#include "alloc-util.h"
|
|
#include "device-util.h"
|
|
#include "dirent-util.h"
|
|
#include "escape.h"
|
|
#include "fd-util.h"
|
|
#include "format-util.h"
|
|
#include "logind-acl.h"
|
|
#include "set.h"
|
|
#include "string-util.h"
|
|
#include "util.h"
|
|
|
|
static int flush_acl(acl_t acl) {
|
|
acl_entry_t i;
|
|
int found;
|
|
bool changed = false;
|
|
|
|
assert(acl);
|
|
|
|
for (found = acl_get_entry(acl, ACL_FIRST_ENTRY, &i);
|
|
found > 0;
|
|
found = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) {
|
|
|
|
acl_tag_t tag;
|
|
|
|
if (acl_get_tag_type(i, &tag) < 0)
|
|
return -errno;
|
|
|
|
if (tag != ACL_USER)
|
|
continue;
|
|
|
|
if (acl_delete_entry(acl, i) < 0)
|
|
return -errno;
|
|
|
|
changed = true;
|
|
}
|
|
|
|
if (found < 0)
|
|
return -errno;
|
|
|
|
return changed;
|
|
}
|
|
|
|
int devnode_acl(const char *path,
|
|
bool flush,
|
|
bool del, uid_t old_uid,
|
|
bool add, uid_t new_uid) {
|
|
|
|
acl_t acl;
|
|
int r = 0;
|
|
bool changed = false;
|
|
|
|
assert(path);
|
|
|
|
acl = acl_get_file(path, ACL_TYPE_ACCESS);
|
|
if (!acl)
|
|
return -errno;
|
|
|
|
if (flush) {
|
|
|
|
r = flush_acl(acl);
|
|
if (r < 0)
|
|
goto finish;
|
|
if (r > 0)
|
|
changed = true;
|
|
|
|
} else if (del && old_uid > 0) {
|
|
acl_entry_t entry;
|
|
|
|
r = acl_find_uid(acl, old_uid, &entry);
|
|
if (r < 0)
|
|
goto finish;
|
|
|
|
if (r > 0) {
|
|
if (acl_delete_entry(acl, entry) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
|
|
changed = true;
|
|
}
|
|
}
|
|
|
|
if (add && new_uid > 0) {
|
|
acl_entry_t entry;
|
|
acl_permset_t permset;
|
|
int rd, wt;
|
|
|
|
r = acl_find_uid(acl, new_uid, &entry);
|
|
if (r < 0)
|
|
goto finish;
|
|
|
|
if (r == 0) {
|
|
if (acl_create_entry(&acl, &entry) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
|
|
if (acl_set_tag_type(entry, ACL_USER) < 0 ||
|
|
acl_set_qualifier(entry, &new_uid) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
}
|
|
|
|
if (acl_get_permset(entry, &permset) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
|
|
rd = acl_get_perm(permset, ACL_READ);
|
|
if (rd < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
|
|
wt = acl_get_perm(permset, ACL_WRITE);
|
|
if (wt < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
|
|
if (!rd || !wt) {
|
|
|
|
if (acl_add_perm(permset, ACL_READ|ACL_WRITE) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
|
|
changed = true;
|
|
}
|
|
}
|
|
|
|
if (!changed)
|
|
goto finish;
|
|
|
|
if (acl_calc_mask(&acl) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
|
|
if (acl_set_file(path, ACL_TYPE_ACCESS, acl) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
|
|
r = 0;
|
|
|
|
finish:
|
|
acl_free(acl);
|
|
|
|
return r;
|
|
}
|
|
|
|
int devnode_acl_all(const char *seat,
|
|
bool flush,
|
|
bool del, uid_t old_uid,
|
|
bool add, uid_t new_uid) {
|
|
|
|
_cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
|
|
_cleanup_set_free_free_ Set *nodes = NULL;
|
|
_cleanup_closedir_ DIR *dir = NULL;
|
|
struct dirent *dent;
|
|
sd_device *d;
|
|
char *n;
|
|
int r;
|
|
|
|
nodes = set_new(&path_hash_ops);
|
|
if (!nodes)
|
|
return -ENOMEM;
|
|
|
|
r = sd_device_enumerator_new(&e);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
if (isempty(seat))
|
|
seat = "seat0";
|
|
|
|
/* We can only match by one tag in libudev. We choose
|
|
* "uaccess" for that. If we could match for two tags here we
|
|
* could add the seat name as second match tag, but this would
|
|
* be hardly optimizable in libudev, and hence checking the
|
|
* second tag manually in our loop is a good solution. */
|
|
r = sd_device_enumerator_add_match_tag(e, "uaccess");
|
|
if (r < 0)
|
|
return r;
|
|
|
|
FOREACH_DEVICE(e, d) {
|
|
const char *node, *sn;
|
|
|
|
/* Make sure the tag is still in place */
|
|
if (sd_device_has_current_tag(d, "uaccess") <= 0)
|
|
continue;
|
|
|
|
if (sd_device_get_property_value(d, "ID_SEAT", &sn) < 0 || isempty(sn))
|
|
sn = "seat0";
|
|
|
|
if (!streq(seat, sn))
|
|
continue;
|
|
|
|
/* In case people mistag devices with nodes, we need to ignore this */
|
|
if (sd_device_get_devname(d, &node) < 0)
|
|
continue;
|
|
|
|
log_device_debug(d, "Found udev node %s for seat %s", node, seat);
|
|
r = set_put_strdup(&nodes, node);
|
|
if (r < 0)
|
|
return r;
|
|
}
|
|
|
|
/* udev exports "dead" device nodes to allow module on-demand loading,
|
|
* these devices are not known to the kernel at this moment */
|
|
dir = opendir("/run/udev/static_node-tags/uaccess");
|
|
if (dir) {
|
|
FOREACH_DIRENT(dent, dir, return -errno) {
|
|
_cleanup_free_ char *unescaped_devname = NULL;
|
|
|
|
if (cunescape(dent->d_name, UNESCAPE_RELAX, &unescaped_devname) < 0)
|
|
return -ENOMEM;
|
|
|
|
n = path_join("/dev", unescaped_devname);
|
|
if (!n)
|
|
return -ENOMEM;
|
|
|
|
log_debug("Found static node %s for seat %s", n, seat);
|
|
r = set_consume(nodes, n);
|
|
if (r == -EEXIST)
|
|
continue;
|
|
if (r < 0)
|
|
return r;
|
|
}
|
|
}
|
|
|
|
r = 0;
|
|
SET_FOREACH(n, nodes) {
|
|
int k;
|
|
|
|
log_debug("Changing ACLs at %s for seat %s (uid "UID_FMT"→"UID_FMT"%s%s)",
|
|
n, seat, old_uid, new_uid,
|
|
del ? " del" : "", add ? " add" : "");
|
|
|
|
k = devnode_acl(n, flush, del, old_uid, add, new_uid);
|
|
if (k == -ENOENT)
|
|
log_debug("Device %s disappeared while setting ACLs", n);
|
|
else if (k < 0 && r == 0)
|
|
r = k;
|
|
}
|
|
|
|
return r;
|
|
}
|