/* 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 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,
  };
  #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 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;
  
  #ifdef CONFIG_KEYS_DEBUG_PROC_KEYS

  	p = proc_create("keys", 0, NULL, &proc_keys_fops);

  	if (!p)
  		panic("Cannot create /proc/keys
  ");

  #endif

  	p = proc_create("key-users", 0, NULL, &proc_key_users_fops);

  	if (!p)
  		panic("Cannot create /proc/key-users
  ");

  	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, '
  ');

  	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);

  	unsigned maxkeys = (user->uid == 0) ?
  		key_quota_root_maxkeys : key_quota_maxkeys;
  	unsigned maxbytes = (user->uid == 0) ?
  		key_quota_root_maxbytes : key_quota_maxbytes;

  
  	seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d
  ",
  		   user->uid,
  		   atomic_read(&user->usage),
  		   atomic_read(&user->nkeys),
  		   atomic_read(&user->nikeys),
  		   user->qnkeys,

  		   maxkeys,

  		   user->qnbytes,

  		   maxbytes);

  
  	return 0;
  
  }