mirror of
				https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
				synced 2025-10-31 16:38:31 +00:00 
			
		
		
		
	 06ec7be557
			
		
	
	
		06ec7be557
		
	
	
	
	
		
			
			Restrict /proc/keys such that only those keys to which the current task is granted View permission are presented. The documentation is also updated to reflect these changes. Signed-off-by: Michael LeMay <mdlemay@epoch.ncsc.mil> Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
		
			
				
	
	
		
			264 lines
		
	
	
		
			6.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			264 lines
		
	
	
		
			6.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* proc.c: proc 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/slab.h>
 | |
| #include <linux/fs.h>
 | |
| #include <linux/proc_fs.h>
 | |
| #include <linux/seq_file.h>
 | |
| #include <asm/errno.h>
 | |
| #include "internal.h"
 | |
| 
 | |
| #ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
 | |
| 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 struct seq_operations proc_keys_ops = {
 | |
| 	.start	= proc_keys_start,
 | |
| 	.next	= proc_keys_next,
 | |
| 	.stop	= proc_keys_stop,
 | |
| 	.show	= proc_keys_show,
 | |
| };
 | |
| 
 | |
| static struct file_operations proc_keys_fops = {
 | |
| 	.open		= proc_keys_open,
 | |
| 	.read		= seq_read,
 | |
| 	.llseek		= seq_lseek,
 | |
| 	.release	= seq_release,
 | |
| };
 | |
| #endif
 | |
| 
 | |
| 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 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 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;
 | |
| 
 | |
| #ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
 | |
| 	p = create_proc_entry("keys", 0, NULL);
 | |
| 	if (!p)
 | |
| 		panic("Cannot create /proc/keys\n");
 | |
| 
 | |
| 	p->proc_fops = &proc_keys_fops;
 | |
| #endif
 | |
| 
 | |
| 	p = create_proc_entry("key-users", 0, NULL);
 | |
| 	if (!p)
 | |
| 		panic("Cannot create /proc/key-users\n");
 | |
| 
 | |
| 	p->proc_fops = &proc_key_users_fops;
 | |
| 
 | |
| 	return 0;
 | |
| 
 | |
| } /* end key_proc_init() */
 | |
| 
 | |
| __initcall(key_proc_init);
 | |
| 
 | |
| /*****************************************************************************/
 | |
| /*
 | |
|  * implement "/proc/keys" to provides a list of the keys on the system
 | |
|  */
 | |
| #ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
 | |
| 
 | |
| static int proc_keys_open(struct inode *inode, struct file *file)
 | |
| {
 | |
| 	return seq_open(file, &proc_keys_ops);
 | |
| 
 | |
| }
 | |
| 
 | |
| static void *proc_keys_start(struct seq_file *p, loff_t *_pos)
 | |
| {
 | |
| 	struct rb_node *_p;
 | |
| 	loff_t pos = *_pos;
 | |
| 
 | |
| 	spin_lock(&key_serial_lock);
 | |
| 
 | |
| 	_p = rb_first(&key_serial_tree);
 | |
| 	while (pos > 0 && _p) {
 | |
| 		pos--;
 | |
| 		_p = rb_next(_p);
 | |
| 	}
 | |
| 
 | |
| 	return _p;
 | |
| 
 | |
| }
 | |
| 
 | |
| static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos)
 | |
| {
 | |
| 	(*_pos)++;
 | |
| 	return rb_next((struct rb_node *) v);
 | |
| 
 | |
| }
 | |
| 
 | |
| static void proc_keys_stop(struct seq_file *p, void *v)
 | |
| {
 | |
| 	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;
 | |
| 	char xbuf[12];
 | |
| 	int rc;
 | |
| 
 | |
| 	/* check whether the current task is allowed to view the key (assuming
 | |
| 	 * non-possession) */
 | |
| 	rc = key_task_permission(make_key_ref(key, 0), current, KEY_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 %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),
 | |
| 		   atomic_read(&key->usage),
 | |
| 		   xbuf,
 | |
| 		   key->perm,
 | |
| 		   key->uid,
 | |
| 		   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;
 | |
| 
 | |
| }
 | |
| 
 | |
| #endif /* CONFIG_KEYS_DEBUG_PROC_KEYS */
 | |
| 
 | |
| /*****************************************************************************/
 | |
| /*
 | |
|  * implement "/proc/key-users" to provides a list of the key users
 | |
|  */
 | |
| 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)
 | |
| {
 | |
| 	struct rb_node *_p;
 | |
| 	loff_t pos = *_pos;
 | |
| 
 | |
| 	spin_lock(&key_user_lock);
 | |
| 
 | |
| 	_p = rb_first(&key_user_tree);
 | |
| 	while (pos > 0 && _p) {
 | |
| 		pos--;
 | |
| 		_p = rb_next(_p);
 | |
| 	}
 | |
| 
 | |
| 	return _p;
 | |
| 
 | |
| }
 | |
| 
 | |
| static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
 | |
| {
 | |
| 	(*_pos)++;
 | |
| 	return rb_next((struct rb_node *) v);
 | |
| 
 | |
| }
 | |
| 
 | |
| static void proc_key_users_stop(struct seq_file *p, void *v)
 | |
| {
 | |
| 	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);
 | |
| 
 | |
| 	seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
 | |
| 		   user->uid,
 | |
| 		   atomic_read(&user->usage),
 | |
| 		   atomic_read(&user->nkeys),
 | |
| 		   atomic_read(&user->nikeys),
 | |
| 		   user->qnkeys,
 | |
| 		   KEYQUOTA_MAX_KEYS,
 | |
| 		   user->qnbytes,
 | |
| 		   KEYQUOTA_MAX_BYTES
 | |
| 		   );
 | |
| 
 | |
| 	return 0;
 | |
| 
 | |
| }
 |