154 lines
3.8 KiB
C
154 lines
3.8 KiB
C
/* drivers/misc/uid_stat.c
|
|
*
|
|
* Copyright (C) 2008 - 2009 Google, Inc.
|
|
*
|
|
* This software is licensed under the terms of the GNU General Public
|
|
* License version 2, as published by the Free Software Foundation, and
|
|
* may be copied, distributed, and modified under those terms.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
*/
|
|
|
|
#include <asm/atomic.h>
|
|
|
|
#include <linux/err.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/list.h>
|
|
#include <linux/proc_fs.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/stat.h>
|
|
#include <linux/uid_stat.h>
|
|
|
|
static DEFINE_SPINLOCK(uid_lock);
|
|
static LIST_HEAD(uid_list);
|
|
static struct proc_dir_entry *parent;
|
|
|
|
struct uid_stat {
|
|
struct list_head link;
|
|
uid_t uid;
|
|
atomic_t tcp_rcv;
|
|
atomic_t tcp_snd;
|
|
};
|
|
|
|
static struct uid_stat *find_uid_stat(uid_t uid) {
|
|
unsigned long flags;
|
|
struct uid_stat *entry;
|
|
|
|
spin_lock_irqsave(&uid_lock, flags);
|
|
list_for_each_entry(entry, &uid_list, link) {
|
|
if (entry->uid == uid) {
|
|
spin_unlock_irqrestore(&uid_lock, flags);
|
|
return entry;
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&uid_lock, flags);
|
|
return NULL;
|
|
}
|
|
|
|
static int tcp_snd_read_proc(char *page, char **start, off_t off,
|
|
int count, int *eof, void *data)
|
|
{
|
|
int len;
|
|
unsigned int bytes;
|
|
char *p = page;
|
|
struct uid_stat *uid_entry = (struct uid_stat *) data;
|
|
if (!data)
|
|
return 0;
|
|
|
|
bytes = (unsigned int) (atomic_read(&uid_entry->tcp_snd) + INT_MIN);
|
|
p += sprintf(p, "%u\n", bytes);
|
|
len = (p - page) - off;
|
|
*eof = (len <= count) ? 1 : 0;
|
|
*start = page + off;
|
|
return len;
|
|
}
|
|
|
|
static int tcp_rcv_read_proc(char *page, char **start, off_t off,
|
|
int count, int *eof, void *data)
|
|
{
|
|
int len;
|
|
unsigned int bytes;
|
|
char *p = page;
|
|
struct uid_stat *uid_entry = (struct uid_stat *) data;
|
|
if (!data)
|
|
return 0;
|
|
|
|
bytes = (unsigned int) (atomic_read(&uid_entry->tcp_rcv) + INT_MIN);
|
|
p += sprintf(p, "%u\n", bytes);
|
|
len = (p - page) - off;
|
|
*eof = (len <= count) ? 1 : 0;
|
|
*start = page + off;
|
|
return len;
|
|
}
|
|
|
|
/* Create a new entry for tracking the specified uid. */
|
|
static struct uid_stat *create_stat(uid_t uid) {
|
|
unsigned long flags;
|
|
char uid_s[32];
|
|
struct uid_stat *new_uid;
|
|
struct proc_dir_entry *entry;
|
|
|
|
/* Create the uid stat struct and append it to the list. */
|
|
if ((new_uid = kmalloc(sizeof(struct uid_stat), GFP_KERNEL)) == NULL)
|
|
return NULL;
|
|
|
|
new_uid->uid = uid;
|
|
/* Counters start at INT_MIN, so we can track 4GB of network traffic. */
|
|
atomic_set(&new_uid->tcp_rcv, INT_MIN);
|
|
atomic_set(&new_uid->tcp_snd, INT_MIN);
|
|
|
|
spin_lock_irqsave(&uid_lock, flags);
|
|
list_add_tail(&new_uid->link, &uid_list);
|
|
spin_unlock_irqrestore(&uid_lock, flags);
|
|
|
|
sprintf(uid_s, "%d", uid);
|
|
entry = proc_mkdir(uid_s, parent);
|
|
|
|
/* Keep reference to uid_stat so we know what uid to read stats from. */
|
|
create_proc_read_entry("tcp_snd", S_IRUGO, entry , tcp_snd_read_proc,
|
|
(void *) new_uid);
|
|
|
|
create_proc_read_entry("tcp_rcv", S_IRUGO, entry, tcp_rcv_read_proc,
|
|
(void *) new_uid);
|
|
|
|
return new_uid;
|
|
}
|
|
|
|
int update_tcp_snd(uid_t uid, int size) {
|
|
struct uid_stat *entry;
|
|
if ((entry = find_uid_stat(uid)) == NULL &&
|
|
((entry = create_stat(uid)) == NULL)) {
|
|
return -1;
|
|
}
|
|
atomic_add(size, &entry->tcp_snd);
|
|
return 0;
|
|
}
|
|
|
|
int update_tcp_rcv(uid_t uid, int size) {
|
|
struct uid_stat *entry;
|
|
if ((entry = find_uid_stat(uid)) == NULL &&
|
|
((entry = create_stat(uid)) == NULL)) {
|
|
return -1;
|
|
}
|
|
atomic_add(size, &entry->tcp_rcv);
|
|
return 0;
|
|
}
|
|
|
|
static int __init uid_stat_init(void)
|
|
{
|
|
parent = proc_mkdir("uid_stat", NULL);
|
|
if (!parent) {
|
|
pr_err("uid_stat: failed to create proc entry\n");
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
__initcall(uid_stat_init);
|