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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
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>
17#include <linux/init.h>
18#include <linux/sched.h>
19#include <linux/module.h>
20#include <linux/bitops.h>
21#include <linux/mount.h>
22#include <linux/nsproxy.h>
23#include <net/net_namespace.h>
24#include <linux/seq_file.h>
25
26#include "internal.h"
27
28
29static struct net *get_proc_net(const struct inode *inode)
30{
31 return maybe_get_net(PDE_NET(PDE(inode)));
32}
33
34int seq_open_net(struct inode *ino, struct file *f,
35 const struct seq_operations *ops, int size)
36{
37 struct net *net;
38 struct seq_net_private *p;
39
40 BUG_ON(size < sizeof(*p));
41
42 net = get_proc_net(ino);
43 if (net == NULL)
44 return -ENXIO;
45
46 p = __seq_open_private(f, ops, size);
47 if (p == NULL) {
48 put_net(net);
49 return -ENOMEM;
50 }
51#ifdef CONFIG_NET_NS
52 p->net = net;
53#endif
54 return 0;
55}
56EXPORT_SYMBOL_GPL(seq_open_net);
57
58int single_open_net(struct inode *inode, struct file *file,
59 int (*show)(struct seq_file *, void *))
60{
61 int err;
62 struct net *net;
63
64 err = -ENXIO;
65 net = get_proc_net(inode);
66 if (net == NULL)
67 goto err_net;
68
69 err = single_open(file, show, net);
70 if (err < 0)
71 goto err_open;
72
73 return 0;
74
75err_open:
76 put_net(net);
77err_net:
78 return err;
79}
80EXPORT_SYMBOL_GPL(single_open_net);
81
82int seq_release_net(struct inode *ino, struct file *f)
83{
84 struct seq_file *seq;
85
86 seq = f->private_data;
87
88 put_net(seq_file_net(seq));
89 seq_release_private(ino, f);
90 return 0;
91}
92EXPORT_SYMBOL_GPL(seq_release_net);
93
94int single_release_net(struct inode *ino, struct file *f)
95{
96 struct seq_file *seq = f->private_data;
97 put_net(seq->private);
98 return single_release(ino, f);
99}
100EXPORT_SYMBOL_GPL(single_release_net);
101
102static struct net *get_proc_task_net(struct inode *dir)
103{
104 struct task_struct *task;
105 struct nsproxy *ns;
106 struct net *net = NULL;
107
108 rcu_read_lock();
109 task = pid_task(proc_pid(dir), PIDTYPE_PID);
110 if (task != NULL) {
111 ns = task_nsproxy(task);
112 if (ns != NULL)
113 net = get_net(ns->net_ns);
114 }
115 rcu_read_unlock();
116
117 return net;
118}
119
120static struct dentry *proc_tgid_net_lookup(struct inode *dir,
121 struct dentry *dentry, struct nameidata *nd)
122{
123 struct dentry *de;
124 struct net *net;
125
126 de = ERR_PTR(-ENOENT);
127 net = get_proc_task_net(dir);
128 if (net != NULL) {
129 de = proc_lookup_de(net->proc_net, dir, dentry);
130 put_net(net);
131 }
132 return de;
133}
134
135static int proc_tgid_net_getattr(struct vfsmount *mnt, struct dentry *dentry,
136 struct kstat *stat)
137{
138 struct inode *inode = dentry->d_inode;
139 struct net *net;
140
141 net = get_proc_task_net(inode);
142
143 generic_fillattr(inode, stat);
144
145 if (net != NULL) {
146 stat->nlink = net->proc_net->nlink;
147 put_net(net);
148 }
149
150 return 0;
151}
152
153const struct inode_operations proc_net_inode_operations = {
154 .lookup = proc_tgid_net_lookup,
155 .getattr = proc_tgid_net_getattr,
156};
157
158static int proc_tgid_net_readdir(struct file *filp, void *dirent,
159 filldir_t filldir)
160{
161 int ret;
162 struct net *net;
163
164 ret = -EINVAL;
165 net = get_proc_task_net(filp->f_path.dentry->d_inode);
166 if (net != NULL) {
167 ret = proc_readdir_de(net->proc_net, filp, dirent, filldir);
168 put_net(net);
169 }
170 return ret;
171}
172
173const struct file_operations proc_net_operations = {
174 .llseek = generic_file_llseek,
175 .read = generic_read_dir,
176 .readdir = proc_tgid_net_readdir,
177};
178
179
180struct proc_dir_entry *proc_net_fops_create(struct net *net,
181 const char *name, mode_t mode, const struct file_operations *fops)
182{
183 return proc_create(name, mode, net->proc_net, fops);
184}
185EXPORT_SYMBOL_GPL(proc_net_fops_create);
186
187void proc_net_remove(struct net *net, const char *name)
188{
189 remove_proc_entry(name, net->proc_net);
190}
191EXPORT_SYMBOL_GPL(proc_net_remove);
192
193static __net_init int proc_net_ns_init(struct net *net)
194{
195 struct proc_dir_entry *netd, *net_statd;
196 int err;
197
198 err = -ENOMEM;
199 netd = kzalloc(sizeof(*netd), GFP_KERNEL);
200 if (!netd)
201 goto out;
202
203 netd->data = net;
204 netd->nlink = 2;
205 netd->name = "net";
206 netd->namelen = 3;
207 netd->parent = &proc_root;
208
209 err = -EEXIST;
210 net_statd = proc_net_mkdir(net, "stat", netd);
211 if (!net_statd)
212 goto free_net;
213
214 net->proc_net = netd;
215 net->proc_net_stat = net_statd;
216 return 0;
217
218free_net:
219 kfree(netd);
220out:
221 return err;
222}
223
224static __net_exit void proc_net_ns_exit(struct net *net)
225{
226 remove_proc_entry("stat", net->proc_net);
227 kfree(net->proc_net);
228}
229
230static struct pernet_operations __net_initdata proc_net_ns_ops = {
231 .init = proc_net_ns_init,
232 .exit = proc_net_ns_exit,
233};
234
235int __init proc_net_init(void)
236{
237 proc_symlink("net", NULL, "self/net");
238
239 return register_pernet_subsys(&proc_net_ns_ops);
240}