--- /dev/null
+/* procfs files for key database enumeration
+ *
+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * 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 Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <asm/errno.h>
+#include "internal.h"
+
+static int proc_keys_open(struct inode *inode, struct file *file);
+static void *proc_keys_start(struct seq_file *p, loff_t *_pos);
+static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos);
+static void proc_keys_stop(struct seq_file *p, void *v);
+static int proc_keys_show(struct seq_file *m, void *v);
+
+static const struct seq_operations proc_keys_ops = {
+ .start = proc_keys_start,
+ .next = proc_keys_next,
+ .stop = proc_keys_stop,
+ .show = proc_keys_show,
+};
+
+static const struct file_operations proc_keys_fops = {
+ .open = proc_keys_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int proc_key_users_open(struct inode *inode, struct file *file);
+static void *proc_key_users_start(struct seq_file *p, loff_t *_pos);
+static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos);
+static void proc_key_users_stop(struct seq_file *p, void *v);
+static int proc_key_users_show(struct seq_file *m, void *v);
+
+static const struct seq_operations proc_key_users_ops = {
+ .start = proc_key_users_start,
+ .next = proc_key_users_next,
+ .stop = proc_key_users_stop,
+ .show = proc_key_users_show,
+};
+
+static const struct file_operations proc_key_users_fops = {
+ .open = proc_key_users_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+/*
+ * Declare the /proc files.
+ */
+static int __init key_proc_init(void)
+{
+ struct proc_dir_entry *p;
+
+ p = proc_create("keys", 0, NULL, &proc_keys_fops);
+ if (!p)
+ panic("Cannot create /proc/keys\n");
+
+ p = proc_create("key-users", 0, NULL, &proc_key_users_fops);
+ if (!p)
+ panic("Cannot create /proc/key-users\n");
+
+ return 0;
+}
+
+__initcall(key_proc_init);
+
+/*
+ * Implement "/proc/keys" to provide a list of the keys on the system that
+ * grant View permission to the caller.
+ */
+static struct rb_node *key_serial_next(struct seq_file *p, struct rb_node *n)
+{
+ struct user_namespace *user_ns = seq_user_ns(p);
+
+ n = rb_next(n);
+ while (n) {
+ struct key *key = rb_entry(n, struct key, serial_node);
+ if (kuid_has_mapping(user_ns, key->user->uid))
+ break;
+ n = rb_next(n);
+ }
+ return n;
+}
+
+static int proc_keys_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &proc_keys_ops);
+}
+
+static struct key *find_ge_key(struct seq_file *p, key_serial_t id)
+{
+ struct user_namespace *user_ns = seq_user_ns(p);
+ struct rb_node *n = key_serial_tree.rb_node;
+ struct key *minkey = NULL;
+
+ while (n) {
+ struct key *key = rb_entry(n, struct key, serial_node);
+ if (id < key->serial) {
+ if (!minkey || minkey->serial > key->serial)
+ minkey = key;
+ n = n->rb_left;
+ } else if (id > key->serial) {
+ n = n->rb_right;
+ } else {
+ minkey = key;
+ break;
+ }
+ key = NULL;
+ }
+
+ if (!minkey)
+ return NULL;
+
+ for (;;) {
+ if (kuid_has_mapping(user_ns, minkey->user->uid))
+ return minkey;
+ n = rb_next(&minkey->serial_node);
+ if (!n)
+ return NULL;
+ minkey = rb_entry(n, struct key, serial_node);
+ }
+}
+
+static void *proc_keys_start(struct seq_file *p, loff_t *_pos)
+ __acquires(key_serial_lock)
+{
+ key_serial_t pos = *_pos;
+ struct key *key;
+
+ spin_lock(&key_serial_lock);
+
+ if (*_pos > INT_MAX)
+ return NULL;
+ key = find_ge_key(p, pos);
+ if (!key)
+ return NULL;
+ *_pos = key->serial;
+ return &key->serial_node;
+}
+
+static inline key_serial_t key_node_serial(struct rb_node *n)
+{
+ struct key *key = rb_entry(n, struct key, serial_node);
+ return key->serial;
+}
+
+static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos)
+{
+ struct rb_node *n;
+
+ n = key_serial_next(p, v);
+ if (n)
+ *_pos = key_node_serial(n);
+ return n;
+}
+
+static void proc_keys_stop(struct seq_file *p, void *v)
+ __releases(key_serial_lock)
+{
+ spin_unlock(&key_serial_lock);
+}
+
+static int proc_keys_show(struct seq_file *m, void *v)
+{
+ struct rb_node *_p = v;
+ struct key *key = rb_entry(_p, struct key, serial_node);
+ struct timespec now;
+ unsigned long timo;
+ key_ref_t key_ref, skey_ref;
+ char xbuf[12];
+ int rc;
+
+ struct keyring_search_context ctx = {
+ .index_key.type = key->type,
+ .index_key.description = key->description,
+ .cred = current_cred(),
+ .match_data.cmp = lookup_user_key_possessed,
+ .match_data.raw_data = key,
+ .match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
+ .flags = KEYRING_SEARCH_NO_STATE_CHECK,
+ };
+
+ key_ref = make_key_ref(key, 0);
+
+ /* determine if the key is possessed by this process (a test we can
+ * skip if the key does not indicate the possessor can view it
+ */
+ if (key->perm & KEY_POS_VIEW) {
+ skey_ref = search_my_process_keyrings(&ctx);
+ if (!IS_ERR(skey_ref)) {
+ key_ref_put(skey_ref);
+ key_ref = make_key_ref(key, 1);
+ }
+ }
+
+ /* check whether the current task is allowed to view the key (assuming
+ * non-possession)
+ * - the caller holds a spinlock, and thus the RCU read lock, making our
+ * access to __current_cred() safe
+ */
+ rc = key_task_permission(key_ref, ctx.cred, KEY_NEED_VIEW);
+ if (rc < 0)
+ return 0;
+
+ now = current_kernel_time();
+
+ rcu_read_lock();
+
+ /* come up with a suitable timeout value */
+ if (key->expiry == 0) {
+ memcpy(xbuf, "perm", 5);
+ } else if (now.tv_sec >= key->expiry) {
+ memcpy(xbuf, "expd", 5);
+ } else {
+ timo = key->expiry - now.tv_sec;
+
+ if (timo < 60)
+ sprintf(xbuf, "%lus", timo);
+ else if (timo < 60*60)
+ sprintf(xbuf, "%lum", timo / 60);
+ else if (timo < 60*60*24)
+ sprintf(xbuf, "%luh", timo / (60*60));
+ else if (timo < 60*60*24*7)
+ sprintf(xbuf, "%lud", timo / (60*60*24));
+ else
+ sprintf(xbuf, "%luw", timo / (60*60*24*7));
+ }
+
+#define showflag(KEY, LETTER, FLAG) \
+ (test_bit(FLAG, &(KEY)->flags) ? LETTER : '-')
+
+ seq_printf(m, "%08x %c%c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
+ key->serial,
+ showflag(key, 'I', KEY_FLAG_INSTANTIATED),
+ showflag(key, 'R', KEY_FLAG_REVOKED),
+ showflag(key, 'D', KEY_FLAG_DEAD),
+ showflag(key, 'Q', KEY_FLAG_IN_QUOTA),
+ showflag(key, 'U', KEY_FLAG_USER_CONSTRUCT),
+ showflag(key, 'N', KEY_FLAG_NEGATIVE),
+ showflag(key, 'i', KEY_FLAG_INVALIDATED),
+ atomic_read(&key->usage),
+ xbuf,
+ key->perm,
+ from_kuid_munged(seq_user_ns(m), key->uid),
+ from_kgid_munged(seq_user_ns(m), key->gid),
+ key->type->name);
+
+#undef showflag
+
+ if (key->type->describe)
+ key->type->describe(key, m);
+ seq_putc(m, '\n');
+
+ rcu_read_unlock();
+ return 0;
+}
+
+static struct rb_node *__key_user_next(struct user_namespace *user_ns, struct rb_node *n)
+{
+ while (n) {
+ struct key_user *user = rb_entry(n, struct key_user, node);
+ if (kuid_has_mapping(user_ns, user->uid))
+ break;
+ n = rb_next(n);
+ }
+ return n;
+}
+
+static struct rb_node *key_user_next(struct user_namespace *user_ns, struct rb_node *n)
+{
+ return __key_user_next(user_ns, rb_next(n));
+}
+
+static struct rb_node *key_user_first(struct user_namespace *user_ns, struct rb_root *r)
+{
+ struct rb_node *n = rb_first(r);
+ return __key_user_next(user_ns, n);
+}
+
+/*
+ * Implement "/proc/key-users" to provides a list of the key users and their
+ * quotas.
+ */
+static int proc_key_users_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &proc_key_users_ops);
+}
+
+static void *proc_key_users_start(struct seq_file *p, loff_t *_pos)
+ __acquires(key_user_lock)
+{
+ struct rb_node *_p;
+ loff_t pos = *_pos;
+
+ spin_lock(&key_user_lock);
+
+ _p = key_user_first(seq_user_ns(p), &key_user_tree);
+ while (pos > 0 && _p) {
+ pos--;
+ _p = key_user_next(seq_user_ns(p), _p);
+ }
+
+ return _p;
+}
+
+static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
+{
+ (*_pos)++;
+ return key_user_next(seq_user_ns(p), (struct rb_node *)v);
+}
+
+static void proc_key_users_stop(struct seq_file *p, void *v)
+ __releases(key_user_lock)
+{
+ spin_unlock(&key_user_lock);
+}
+
+static int proc_key_users_show(struct seq_file *m, void *v)
+{
+ struct rb_node *_p = v;
+ struct key_user *user = rb_entry(_p, struct key_user, node);
+ unsigned maxkeys = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
+ key_quota_root_maxkeys : key_quota_maxkeys;
+ unsigned maxbytes = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
+ key_quota_root_maxbytes : key_quota_maxbytes;
+
+ seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
+ from_kuid_munged(seq_user_ns(m), user->uid),
+ atomic_read(&user->usage),
+ atomic_read(&user->nkeys),
+ atomic_read(&user->nikeys),
+ user->qnkeys,
+ maxkeys,
+ user->qnbytes,
+ maxbytes);
+
+ return 0;
+}
Code Review / kvmfornfv.git / blobdiff