blob: a63af3e0a6126b4445bb9a3cef8687038e670b58 [file] [log] [blame]
David S. Miller3c12afe2007-09-12 14:18:18 +02001/*
2 * linux/fs/proc/net.c
3 *
4 * Copyright (C) 2007
5 *
6 * Author: Eric Biederman <ebiederm@xmission.com>
7 *
8 * proc net directory handling functions
9 */
10
11#include <asm/uaccess.h>
12
13#include <linux/errno.h>
14#include <linux/time.h>
15#include <linux/proc_fs.h>
16#include <linux/stat.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090017#include <linux/slab.h>
David S. Miller3c12afe2007-09-12 14:18:18 +020018#include <linux/init.h>
19#include <linux/sched.h>
20#include <linux/module.h>
21#include <linux/bitops.h>
David S. Miller3c12afe2007-09-12 14:18:18 +020022#include <linux/mount.h>
23#include <linux/nsproxy.h>
24#include <net/net_namespace.h>
Denis V. Luneve372c412007-11-19 22:31:54 -080025#include <linux/seq_file.h>
David S. Miller3c12afe2007-09-12 14:18:18 +020026
27#include "internal.h"
28
David Howells4abfd022013-04-12 02:09:03 +010029static inline struct net *PDE_NET(struct proc_dir_entry *pde)
30{
31 return pde->parent->data;
32}
David S. Miller3c12afe2007-09-12 14:18:18 +020033
Adrian Bunk8086cd42008-07-22 14:19:19 -070034static struct net *get_proc_net(const struct inode *inode)
35{
36 return maybe_get_net(PDE_NET(PDE(inode)));
37}
38
Denis V. Luneve372c412007-11-19 22:31:54 -080039int seq_open_net(struct inode *ino, struct file *f,
40 const struct seq_operations *ops, int size)
41{
42 struct net *net;
43 struct seq_net_private *p;
44
45 BUG_ON(size < sizeof(*p));
46
47 net = get_proc_net(ino);
48 if (net == NULL)
49 return -ENXIO;
50
51 p = __seq_open_private(f, ops, size);
52 if (p == NULL) {
53 put_net(net);
54 return -ENOMEM;
55 }
YOSHIFUJI Hideaki12188542008-03-26 02:36:06 +090056#ifdef CONFIG_NET_NS
Denis V. Luneve372c412007-11-19 22:31:54 -080057 p->net = net;
YOSHIFUJI Hideaki12188542008-03-26 02:36:06 +090058#endif
Denis V. Luneve372c412007-11-19 22:31:54 -080059 return 0;
60}
61EXPORT_SYMBOL_GPL(seq_open_net);
62
Pavel Emelyanovde05c552008-07-18 04:07:21 -070063int single_open_net(struct inode *inode, struct file *file,
64 int (*show)(struct seq_file *, void *))
65{
66 int err;
67 struct net *net;
68
69 err = -ENXIO;
70 net = get_proc_net(inode);
71 if (net == NULL)
72 goto err_net;
73
74 err = single_open(file, show, net);
75 if (err < 0)
76 goto err_open;
77
78 return 0;
79
80err_open:
81 put_net(net);
82err_net:
83 return err;
84}
85EXPORT_SYMBOL_GPL(single_open_net);
86
Denis V. Luneve372c412007-11-19 22:31:54 -080087int seq_release_net(struct inode *ino, struct file *f)
88{
89 struct seq_file *seq;
Denis V. Luneve372c412007-11-19 22:31:54 -080090
91 seq = f->private_data;
Denis V. Luneve372c412007-11-19 22:31:54 -080092
YOSHIFUJI Hideaki12188542008-03-26 02:36:06 +090093 put_net(seq_file_net(seq));
Denis V. Luneve372c412007-11-19 22:31:54 -080094 seq_release_private(ino, f);
95 return 0;
96}
97EXPORT_SYMBOL_GPL(seq_release_net);
98
Pavel Emelyanovb6fcbdb2008-07-18 04:07:44 -070099int single_release_net(struct inode *ino, struct file *f)
100{
101 struct seq_file *seq = f->private_data;
102 put_net(seq->private);
103 return single_release(ino, f);
104}
105EXPORT_SYMBOL_GPL(single_release_net);
106
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800107static struct net *get_proc_task_net(struct inode *dir)
108{
109 struct task_struct *task;
110 struct nsproxy *ns;
111 struct net *net = NULL;
112
113 rcu_read_lock();
114 task = pid_task(proc_pid(dir), PIDTYPE_PID);
115 if (task != NULL) {
Eric W. Biederman728dba32014-02-03 19:13:49 -0800116 task_lock(task);
117 ns = task->nsproxy;
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800118 if (ns != NULL)
119 net = get_net(ns->net_ns);
Eric W. Biederman728dba32014-02-03 19:13:49 -0800120 task_unlock(task);
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800121 }
122 rcu_read_unlock();
123
124 return net;
125}
126
127static struct dentry *proc_tgid_net_lookup(struct inode *dir,
Al Viro00cd8dd2012-06-10 17:13:09 -0400128 struct dentry *dentry, unsigned int flags)
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800129{
130 struct dentry *de;
131 struct net *net;
132
133 de = ERR_PTR(-ENOENT);
134 net = get_proc_task_net(dir);
135 if (net != NULL) {
136 de = proc_lookup_de(net->proc_net, dir, dentry);
137 put_net(net);
138 }
139 return de;
140}
141
142static int proc_tgid_net_getattr(struct vfsmount *mnt, struct dentry *dentry,
143 struct kstat *stat)
144{
145 struct inode *inode = dentry->d_inode;
146 struct net *net;
147
148 net = get_proc_task_net(inode);
149
150 generic_fillattr(inode, stat);
151
152 if (net != NULL) {
153 stat->nlink = net->proc_net->nlink;
154 put_net(net);
155 }
156
157 return 0;
158}
159
160const struct inode_operations proc_net_inode_operations = {
161 .lookup = proc_tgid_net_lookup,
162 .getattr = proc_tgid_net_getattr,
163};
164
Al Virof0c3b502013-05-16 12:07:31 -0400165static int proc_tgid_net_readdir(struct file *file, struct dir_context *ctx)
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800166{
167 int ret;
168 struct net *net;
169
170 ret = -EINVAL;
Al Virof0c3b502013-05-16 12:07:31 -0400171 net = get_proc_task_net(file_inode(file));
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800172 if (net != NULL) {
Al Virof0c3b502013-05-16 12:07:31 -0400173 ret = proc_readdir_de(net->proc_net, file, ctx);
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800174 put_net(net);
175 }
176 return ret;
177}
178
179const struct file_operations proc_net_operations = {
Alexey Dobriyanb4df2b92008-10-27 22:48:36 +0300180 .llseek = generic_file_llseek,
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800181 .read = generic_read_dir,
Al Virof0c3b502013-05-16 12:07:31 -0400182 .iterate = proc_tgid_net_readdir,
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800183};
184
Pavel Emelyanov46650792007-10-08 20:38:39 -0700185static __net_init int proc_net_ns_init(struct net *net)
David S. Miller3c12afe2007-09-12 14:18:18 +0200186{
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800187 struct proc_dir_entry *netd, *net_statd;
David S. Miller3c12afe2007-09-12 14:18:18 +0200188 int err;
189
190 err = -ENOMEM;
David Howells09570f92011-07-27 21:47:03 +0300191 netd = kzalloc(sizeof(*netd) + 4, GFP_KERNEL);
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800192 if (!netd)
David S. Miller3c12afe2007-09-12 14:18:18 +0200193 goto out;
194
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800195 netd->data = net;
196 netd->nlink = 2;
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800197 netd->namelen = 3;
198 netd->parent = &proc_root;
David Howells09570f92011-07-27 21:47:03 +0300199 memcpy(netd->name, "net", 4);
David S. Miller3c12afe2007-09-12 14:18:18 +0200200
201 err = -EEXIST;
Denis V. Luneve5d69b92008-01-10 03:51:41 -0800202 net_statd = proc_net_mkdir(net, "stat", netd);
David S. Miller3c12afe2007-09-12 14:18:18 +0200203 if (!net_statd)
204 goto free_net;
205
David S. Miller3c12afe2007-09-12 14:18:18 +0200206 net->proc_net = netd;
207 net->proc_net_stat = net_statd;
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800208 return 0;
David S. Miller3c12afe2007-09-12 14:18:18 +0200209
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800210free_net:
211 kfree(netd);
David S. Miller3c12afe2007-09-12 14:18:18 +0200212out:
213 return err;
David S. Miller3c12afe2007-09-12 14:18:18 +0200214}
215
Pavel Emelyanov46650792007-10-08 20:38:39 -0700216static __net_exit void proc_net_ns_exit(struct net *net)
David S. Miller3c12afe2007-09-12 14:18:18 +0200217{
218 remove_proc_entry("stat", net->proc_net);
Pavel Emelyanove9720ac2008-03-07 11:08:40 -0800219 kfree(net->proc_net);
David S. Miller3c12afe2007-09-12 14:18:18 +0200220}
221
Denis V. Lunev022cbae2007-11-13 03:23:50 -0800222static struct pernet_operations __net_initdata proc_net_ns_ops = {
David S. Miller3c12afe2007-09-12 14:18:18 +0200223 .init = proc_net_ns_init,
224 .exit = proc_net_ns_exit,
225};
226
Pavel Emelyanov46650792007-10-08 20:38:39 -0700227int __init proc_net_init(void)
David S. Miller3c12afe2007-09-12 14:18:18 +0200228{
Linus Torvalds155134f2014-08-10 21:24:59 -0700229 proc_symlink("net", NULL, "self/net");
David S. Miller3c12afe2007-09-12 14:18:18 +0200230
231 return register_pernet_subsys(&proc_net_ns_ops);
232}