1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* procfs files for key database enumeration
4 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
8 #include <linux/init.h>
9 #include <linux/sched.h>
11 #include <linux/proc_fs.h>
12 #include <linux/seq_file.h>
13 #include <asm/errno.h>
16 static void *proc_keys_start(struct seq_file *p, loff_t *_pos);
17 static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos);
18 static void proc_keys_stop(struct seq_file *p, void *v);
19 static int proc_keys_show(struct seq_file *m, void *v);
21 static const struct seq_operations proc_keys_ops = {
22 .start = proc_keys_start,
23 .next = proc_keys_next,
24 .stop = proc_keys_stop,
25 .show = proc_keys_show,
28 static void *proc_key_users_start(struct seq_file *p, loff_t *_pos);
29 static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos);
30 static void proc_key_users_stop(struct seq_file *p, void *v);
31 static int proc_key_users_show(struct seq_file *m, void *v);
33 static const struct seq_operations proc_key_users_ops = {
34 .start = proc_key_users_start,
35 .next = proc_key_users_next,
36 .stop = proc_key_users_stop,
37 .show = proc_key_users_show,
41 * Declare the /proc files.
43 static int __init key_proc_init(void)
45 struct proc_dir_entry *p;
47 p = proc_create_seq("keys", 0, NULL, &proc_keys_ops);
49 panic("Cannot create /proc/keys\n");
51 p = proc_create_seq("key-users", 0, NULL, &proc_key_users_ops);
53 panic("Cannot create /proc/key-users\n");
58 __initcall(key_proc_init);
61 * Implement "/proc/keys" to provide a list of the keys on the system that
62 * grant View permission to the caller.
64 static struct rb_node *key_serial_next(struct seq_file *p, struct rb_node *n)
66 struct user_namespace *user_ns = seq_user_ns(p);
70 struct key *key = rb_entry(n, struct key, serial_node);
71 if (kuid_has_mapping(user_ns, key->user->uid))
78 static struct key *find_ge_key(struct seq_file *p, key_serial_t id)
80 struct user_namespace *user_ns = seq_user_ns(p);
81 struct rb_node *n = key_serial_tree.rb_node;
82 struct key *minkey = NULL;
85 struct key *key = rb_entry(n, struct key, serial_node);
86 if (id < key->serial) {
87 if (!minkey || minkey->serial > key->serial)
90 } else if (id > key->serial) {
103 if (kuid_has_mapping(user_ns, minkey->user->uid))
105 n = rb_next(&minkey->serial_node);
108 minkey = rb_entry(n, struct key, serial_node);
112 static void *proc_keys_start(struct seq_file *p, loff_t *_pos)
114 __acquires(key_serial_lock)
116 key_serial_t pos = *_pos;
120 spin_lock(&key_serial_lock);
124 key = find_ge_key(p, pos);
128 return &key->serial_node;
131 static inline key_serial_t key_node_serial(struct rb_node *n)
133 struct key *key = rb_entry(n, struct key, serial_node);
137 static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos)
141 n = key_serial_next(p, v);
143 *_pos = key_node_serial(n);
147 static void proc_keys_stop(struct seq_file *p, void *v)
148 __releases(key_serial_lock)
151 spin_unlock(&key_serial_lock);
155 static int proc_keys_show(struct seq_file *m, void *v)
157 const struct key_acl *acl;
158 struct rb_node *_p = v;
159 struct key *key = rb_entry(_p, struct key, serial_node);
161 key_ref_t key_ref, skey_ref;
162 time64_t now, expiry;
169 struct keyring_search_context ctx = {
170 .index_key = key->index_key,
171 .cred = m->file->f_cred,
172 .match_data.cmp = lookup_user_key_possessed,
173 .match_data.raw_data = key,
174 .match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
175 .flags = (KEYRING_SEARCH_NO_STATE_CHECK |
176 KEYRING_SEARCH_RECURSE),
179 acl = rcu_dereference(key->acl);
180 check_pos = acl->possessor_viewable;
182 /* determine if the key is possessed by this process (a test we can
183 * skip if the key does not indicate the possessor can view it
185 key_ref = make_key_ref(key, 0);
187 skey_ref = search_cred_keyrings_rcu(&ctx);
188 if (!IS_ERR(skey_ref)) {
189 key_ref_put(skey_ref);
190 key_ref = make_key_ref(key, 1);
194 /* check whether the current task is allowed to view the key */
195 rc = key_task_permission(key_ref, ctx.cred, KEY_NEED_VIEW);
199 now = ktime_get_real_seconds();
201 /* come up with a suitable timeout value */
202 expiry = READ_ONCE(key->expiry);
204 memcpy(xbuf, "perm", 5);
205 } else if (now >= expiry) {
206 memcpy(xbuf, "expd", 5);
211 sprintf(xbuf, "%llus", timo);
212 else if (timo < 60*60)
213 sprintf(xbuf, "%llum", div_u64(timo, 60));
214 else if (timo < 60*60*24)
215 sprintf(xbuf, "%lluh", div_u64(timo, 60 * 60));
216 else if (timo < 60*60*24*7)
217 sprintf(xbuf, "%llud", div_u64(timo, 60 * 60 * 24));
219 sprintf(xbuf, "%lluw", div_u64(timo, 60 * 60 * 24 * 7));
222 state = key_read_state(key);
224 #define showflag(FLAGS, LETTER, FLAG) \
225 ((FLAGS & (1 << FLAG)) ? LETTER : '-')
227 flags = READ_ONCE(key->flags);
228 seq_printf(m, "%08x %c%c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
230 state != KEY_IS_UNINSTANTIATED ? 'I' : '-',
231 showflag(flags, 'R', KEY_FLAG_REVOKED),
232 showflag(flags, 'D', KEY_FLAG_DEAD),
233 showflag(flags, 'Q', KEY_FLAG_IN_QUOTA),
234 showflag(flags, 'U', KEY_FLAG_USER_CONSTRUCT),
235 state < 0 ? 'N' : '-',
236 showflag(flags, 'i', KEY_FLAG_INVALIDATED),
237 refcount_read(&key->usage),
239 key_acl_to_perm(acl),
240 from_kuid_munged(seq_user_ns(m), key->uid),
241 from_kgid_munged(seq_user_ns(m), key->gid),
246 if (key->type->describe)
247 key->type->describe(key, m);
254 static struct rb_node *__key_user_next(struct user_namespace *user_ns, struct rb_node *n)
257 struct key_user *user = rb_entry(n, struct key_user, node);
258 if (kuid_has_mapping(user_ns, user->uid))
265 static struct rb_node *key_user_next(struct user_namespace *user_ns, struct rb_node *n)
267 return __key_user_next(user_ns, rb_next(n));
270 static struct rb_node *key_user_first(struct user_namespace *user_ns, struct rb_root *r)
272 struct rb_node *n = rb_first(r);
273 return __key_user_next(user_ns, n);
276 static void *proc_key_users_start(struct seq_file *p, loff_t *_pos)
277 __acquires(key_user_lock)
282 spin_lock(&key_user_lock);
284 _p = key_user_first(seq_user_ns(p), &key_user_tree);
285 while (pos > 0 && _p) {
287 _p = key_user_next(seq_user_ns(p), _p);
293 static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
296 return key_user_next(seq_user_ns(p), (struct rb_node *)v);
299 static void proc_key_users_stop(struct seq_file *p, void *v)
300 __releases(key_user_lock)
302 spin_unlock(&key_user_lock);
305 static int proc_key_users_show(struct seq_file *m, void *v)
307 struct rb_node *_p = v;
308 struct key_user *user = rb_entry(_p, struct key_user, node);
309 unsigned maxkeys = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
310 key_quota_root_maxkeys : key_quota_maxkeys;
311 unsigned maxbytes = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
312 key_quota_root_maxbytes : key_quota_maxbytes;
314 seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
315 from_kuid_munged(seq_user_ns(m), user->uid),
316 refcount_read(&user->usage),
317 atomic_read(&user->nkeys),
318 atomic_read(&user->nikeys),