David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 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/smp_lock.h> |
| 22 | #include <linux/mount.h> |
| 23 | #include <linux/nsproxy.h> |
| 24 | #include <net/net_namespace.h> |
| 25 | |
| 26 | #include "internal.h" |
| 27 | |
| 28 | |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 29 | struct proc_dir_entry *proc_net_fops_create(struct net *net, |
| 30 | const char *name, mode_t mode, const struct file_operations *fops) |
| 31 | { |
| 32 | struct proc_dir_entry *res; |
| 33 | |
| 34 | res = create_proc_entry(name, mode, net->proc_net); |
| 35 | if (res) |
| 36 | res->proc_fops = fops; |
| 37 | return res; |
| 38 | } |
Daniel Lezcano | 36ac313 | 2007-09-12 14:51:47 +0200 | [diff] [blame] | 39 | EXPORT_SYMBOL_GPL(proc_net_fops_create); |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 40 | |
| 41 | void proc_net_remove(struct net *net, const char *name) |
| 42 | { |
| 43 | remove_proc_entry(name, net->proc_net); |
| 44 | } |
Daniel Lezcano | 36ac313 | 2007-09-12 14:51:47 +0200 | [diff] [blame] | 45 | EXPORT_SYMBOL_GPL(proc_net_remove); |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 46 | |
Eric W. Biederman | 077130c | 2007-09-13 09:18:57 +0200 | [diff] [blame] | 47 | struct net *get_proc_net(const struct inode *inode) |
| 48 | { |
| 49 | return maybe_get_net(PDE_NET(PDE(inode))); |
| 50 | } |
| 51 | EXPORT_SYMBOL_GPL(get_proc_net); |
| 52 | |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 53 | static struct proc_dir_entry *proc_net_shadow; |
| 54 | |
| 55 | static struct dentry *proc_net_shadow_dentry(struct dentry *parent, |
| 56 | struct proc_dir_entry *de) |
| 57 | { |
| 58 | struct dentry *shadow = NULL; |
| 59 | struct inode *inode; |
| 60 | if (!de) |
| 61 | goto out; |
| 62 | de_get(de); |
| 63 | inode = proc_get_inode(parent->d_inode->i_sb, de->low_ino, de); |
| 64 | if (!inode) |
| 65 | goto out_de_put; |
| 66 | shadow = d_alloc_name(parent, de->name); |
| 67 | if (!shadow) |
| 68 | goto out_iput; |
| 69 | shadow->d_op = parent->d_op; /* proc_dentry_operations */ |
| 70 | d_instantiate(shadow, inode); |
| 71 | out: |
| 72 | return shadow; |
| 73 | out_iput: |
| 74 | iput(inode); |
| 75 | out_de_put: |
| 76 | de_put(de); |
| 77 | goto out; |
| 78 | } |
| 79 | |
| 80 | static void *proc_net_follow_link(struct dentry *parent, struct nameidata *nd) |
| 81 | { |
| 82 | struct net *net = current->nsproxy->net_ns; |
| 83 | struct dentry *shadow; |
| 84 | shadow = proc_net_shadow_dentry(parent, net->proc_net); |
| 85 | if (!shadow) |
| 86 | return ERR_PTR(-ENOENT); |
| 87 | |
| 88 | dput(nd->dentry); |
| 89 | /* My dentry count is 1 and that should be enough as the |
| 90 | * shadow dentry is thrown away immediately. |
| 91 | */ |
| 92 | nd->dentry = shadow; |
| 93 | return NULL; |
| 94 | } |
| 95 | |
| 96 | static struct dentry *proc_net_lookup(struct inode *dir, struct dentry *dentry, |
| 97 | struct nameidata *nd) |
| 98 | { |
| 99 | struct net *net = current->nsproxy->net_ns; |
| 100 | struct dentry *shadow; |
| 101 | |
| 102 | shadow = proc_net_shadow_dentry(nd->dentry, net->proc_net); |
| 103 | if (!shadow) |
| 104 | return ERR_PTR(-ENOENT); |
| 105 | |
| 106 | dput(nd->dentry); |
| 107 | nd->dentry = shadow; |
| 108 | |
| 109 | return shadow->d_inode->i_op->lookup(shadow->d_inode, dentry, nd); |
| 110 | } |
| 111 | |
| 112 | static int proc_net_setattr(struct dentry *dentry, struct iattr *iattr) |
| 113 | { |
| 114 | struct net *net = current->nsproxy->net_ns; |
| 115 | struct dentry *shadow; |
| 116 | int ret; |
| 117 | |
| 118 | shadow = proc_net_shadow_dentry(dentry->d_parent, net->proc_net); |
| 119 | if (!shadow) |
| 120 | return -ENOENT; |
| 121 | ret = shadow->d_inode->i_op->setattr(shadow, iattr); |
| 122 | dput(shadow); |
| 123 | return ret; |
| 124 | } |
| 125 | |
| 126 | static const struct file_operations proc_net_dir_operations = { |
| 127 | .read = generic_read_dir, |
| 128 | }; |
| 129 | |
| 130 | static struct inode_operations proc_net_dir_inode_operations = { |
| 131 | .follow_link = proc_net_follow_link, |
| 132 | .lookup = proc_net_lookup, |
| 133 | .setattr = proc_net_setattr, |
| 134 | }; |
| 135 | |
Pavel Emelyanov | 4665079 | 2007-10-08 20:38:39 -0700 | [diff] [blame] | 136 | static __net_init int proc_net_ns_init(struct net *net) |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 137 | { |
| 138 | struct proc_dir_entry *root, *netd, *net_statd; |
| 139 | int err; |
| 140 | |
| 141 | err = -ENOMEM; |
| 142 | root = kzalloc(sizeof(*root), GFP_KERNEL); |
| 143 | if (!root) |
| 144 | goto out; |
| 145 | |
| 146 | err = -EEXIST; |
| 147 | netd = proc_mkdir("net", root); |
| 148 | if (!netd) |
| 149 | goto free_root; |
| 150 | |
| 151 | err = -EEXIST; |
| 152 | net_statd = proc_mkdir("stat", netd); |
| 153 | if (!net_statd) |
| 154 | goto free_net; |
| 155 | |
| 156 | root->data = net; |
| 157 | netd->data = net; |
| 158 | net_statd->data = net; |
| 159 | |
| 160 | net->proc_net_root = root; |
| 161 | net->proc_net = netd; |
| 162 | net->proc_net_stat = net_statd; |
| 163 | err = 0; |
| 164 | |
| 165 | out: |
| 166 | return err; |
| 167 | free_net: |
| 168 | remove_proc_entry("net", root); |
| 169 | free_root: |
| 170 | kfree(root); |
| 171 | goto out; |
| 172 | } |
| 173 | |
Pavel Emelyanov | 4665079 | 2007-10-08 20:38:39 -0700 | [diff] [blame] | 174 | static __net_exit void proc_net_ns_exit(struct net *net) |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 175 | { |
| 176 | remove_proc_entry("stat", net->proc_net); |
| 177 | remove_proc_entry("net", net->proc_net_root); |
| 178 | kfree(net->proc_net_root); |
| 179 | } |
| 180 | |
Denis V. Lunev | 022cbae | 2007-11-13 03:23:50 -0800 | [diff] [blame^] | 181 | static struct pernet_operations __net_initdata proc_net_ns_ops = { |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 182 | .init = proc_net_ns_init, |
| 183 | .exit = proc_net_ns_exit, |
| 184 | }; |
| 185 | |
Pavel Emelyanov | 4665079 | 2007-10-08 20:38:39 -0700 | [diff] [blame] | 186 | int __init proc_net_init(void) |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 187 | { |
| 188 | proc_net_shadow = proc_mkdir("net", NULL); |
| 189 | proc_net_shadow->proc_iops = &proc_net_dir_inode_operations; |
| 190 | proc_net_shadow->proc_fops = &proc_net_dir_operations; |
| 191 | |
| 192 | return register_pernet_subsys(&proc_net_ns_ops); |
| 193 | } |