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 | |
| 29 | struct proc_dir_entry *proc_net_create(struct net *net, |
| 30 | const char *name, mode_t mode, get_info_t *get_info) |
| 31 | { |
| 32 | return create_proc_info_entry(name,mode, net->proc_net, get_info); |
| 33 | } |
Daniel Lezcano | 36ac313 | 2007-09-12 14:51:47 +0200 | [diff] [blame] | 34 | EXPORT_SYMBOL_GPL(proc_net_create); |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 35 | |
| 36 | struct proc_dir_entry *proc_net_fops_create(struct net *net, |
| 37 | const char *name, mode_t mode, const struct file_operations *fops) |
| 38 | { |
| 39 | struct proc_dir_entry *res; |
| 40 | |
| 41 | res = create_proc_entry(name, mode, net->proc_net); |
| 42 | if (res) |
| 43 | res->proc_fops = fops; |
| 44 | return res; |
| 45 | } |
Daniel Lezcano | 36ac313 | 2007-09-12 14:51:47 +0200 | [diff] [blame] | 46 | EXPORT_SYMBOL_GPL(proc_net_fops_create); |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 47 | |
| 48 | void proc_net_remove(struct net *net, const char *name) |
| 49 | { |
| 50 | remove_proc_entry(name, net->proc_net); |
| 51 | } |
Daniel Lezcano | 36ac313 | 2007-09-12 14:51:47 +0200 | [diff] [blame] | 52 | EXPORT_SYMBOL_GPL(proc_net_remove); |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 53 | |
Eric W. Biederman | 077130c | 2007-09-13 09:18:57 +0200 | [diff] [blame] | 54 | struct net *get_proc_net(const struct inode *inode) |
| 55 | { |
| 56 | return maybe_get_net(PDE_NET(PDE(inode))); |
| 57 | } |
| 58 | EXPORT_SYMBOL_GPL(get_proc_net); |
| 59 | |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 60 | static struct proc_dir_entry *proc_net_shadow; |
| 61 | |
| 62 | static struct dentry *proc_net_shadow_dentry(struct dentry *parent, |
| 63 | struct proc_dir_entry *de) |
| 64 | { |
| 65 | struct dentry *shadow = NULL; |
| 66 | struct inode *inode; |
| 67 | if (!de) |
| 68 | goto out; |
| 69 | de_get(de); |
| 70 | inode = proc_get_inode(parent->d_inode->i_sb, de->low_ino, de); |
| 71 | if (!inode) |
| 72 | goto out_de_put; |
| 73 | shadow = d_alloc_name(parent, de->name); |
| 74 | if (!shadow) |
| 75 | goto out_iput; |
| 76 | shadow->d_op = parent->d_op; /* proc_dentry_operations */ |
| 77 | d_instantiate(shadow, inode); |
| 78 | out: |
| 79 | return shadow; |
| 80 | out_iput: |
| 81 | iput(inode); |
| 82 | out_de_put: |
| 83 | de_put(de); |
| 84 | goto out; |
| 85 | } |
| 86 | |
| 87 | static void *proc_net_follow_link(struct dentry *parent, struct nameidata *nd) |
| 88 | { |
| 89 | struct net *net = current->nsproxy->net_ns; |
| 90 | struct dentry *shadow; |
| 91 | shadow = proc_net_shadow_dentry(parent, net->proc_net); |
| 92 | if (!shadow) |
| 93 | return ERR_PTR(-ENOENT); |
| 94 | |
| 95 | dput(nd->dentry); |
| 96 | /* My dentry count is 1 and that should be enough as the |
| 97 | * shadow dentry is thrown away immediately. |
| 98 | */ |
| 99 | nd->dentry = shadow; |
| 100 | return NULL; |
| 101 | } |
| 102 | |
| 103 | static struct dentry *proc_net_lookup(struct inode *dir, struct dentry *dentry, |
| 104 | struct nameidata *nd) |
| 105 | { |
| 106 | struct net *net = current->nsproxy->net_ns; |
| 107 | struct dentry *shadow; |
| 108 | |
| 109 | shadow = proc_net_shadow_dentry(nd->dentry, net->proc_net); |
| 110 | if (!shadow) |
| 111 | return ERR_PTR(-ENOENT); |
| 112 | |
| 113 | dput(nd->dentry); |
| 114 | nd->dentry = shadow; |
| 115 | |
| 116 | return shadow->d_inode->i_op->lookup(shadow->d_inode, dentry, nd); |
| 117 | } |
| 118 | |
| 119 | static int proc_net_setattr(struct dentry *dentry, struct iattr *iattr) |
| 120 | { |
| 121 | struct net *net = current->nsproxy->net_ns; |
| 122 | struct dentry *shadow; |
| 123 | int ret; |
| 124 | |
| 125 | shadow = proc_net_shadow_dentry(dentry->d_parent, net->proc_net); |
| 126 | if (!shadow) |
| 127 | return -ENOENT; |
| 128 | ret = shadow->d_inode->i_op->setattr(shadow, iattr); |
| 129 | dput(shadow); |
| 130 | return ret; |
| 131 | } |
| 132 | |
| 133 | static const struct file_operations proc_net_dir_operations = { |
| 134 | .read = generic_read_dir, |
| 135 | }; |
| 136 | |
| 137 | static struct inode_operations proc_net_dir_inode_operations = { |
| 138 | .follow_link = proc_net_follow_link, |
| 139 | .lookup = proc_net_lookup, |
| 140 | .setattr = proc_net_setattr, |
| 141 | }; |
| 142 | |
Pavel Emelyanov | 4665079 | 2007-10-08 20:38:39 -0700 | [diff] [blame] | 143 | static __net_init int proc_net_ns_init(struct net *net) |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 144 | { |
| 145 | struct proc_dir_entry *root, *netd, *net_statd; |
| 146 | int err; |
| 147 | |
| 148 | err = -ENOMEM; |
| 149 | root = kzalloc(sizeof(*root), GFP_KERNEL); |
| 150 | if (!root) |
| 151 | goto out; |
| 152 | |
| 153 | err = -EEXIST; |
| 154 | netd = proc_mkdir("net", root); |
| 155 | if (!netd) |
| 156 | goto free_root; |
| 157 | |
| 158 | err = -EEXIST; |
| 159 | net_statd = proc_mkdir("stat", netd); |
| 160 | if (!net_statd) |
| 161 | goto free_net; |
| 162 | |
| 163 | root->data = net; |
| 164 | netd->data = net; |
| 165 | net_statd->data = net; |
| 166 | |
| 167 | net->proc_net_root = root; |
| 168 | net->proc_net = netd; |
| 169 | net->proc_net_stat = net_statd; |
| 170 | err = 0; |
| 171 | |
| 172 | out: |
| 173 | return err; |
| 174 | free_net: |
| 175 | remove_proc_entry("net", root); |
| 176 | free_root: |
| 177 | kfree(root); |
| 178 | goto out; |
| 179 | } |
| 180 | |
Pavel Emelyanov | 4665079 | 2007-10-08 20:38:39 -0700 | [diff] [blame] | 181 | static __net_exit void proc_net_ns_exit(struct net *net) |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 182 | { |
| 183 | remove_proc_entry("stat", net->proc_net); |
| 184 | remove_proc_entry("net", net->proc_net_root); |
| 185 | kfree(net->proc_net_root); |
| 186 | } |
| 187 | |
Adrian Bunk | 253879e | 2007-10-26 03:55:44 -0700 | [diff] [blame] | 188 | static struct pernet_operations __net_initdata proc_net_ns_ops = { |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 189 | .init = proc_net_ns_init, |
| 190 | .exit = proc_net_ns_exit, |
| 191 | }; |
| 192 | |
Pavel Emelyanov | 4665079 | 2007-10-08 20:38:39 -0700 | [diff] [blame] | 193 | int __init proc_net_init(void) |
David S. Miller | 3c12afe | 2007-09-12 14:18:18 +0200 | [diff] [blame] | 194 | { |
| 195 | proc_net_shadow = proc_mkdir("net", NULL); |
| 196 | proc_net_shadow->proc_iops = &proc_net_dir_inode_operations; |
| 197 | proc_net_shadow->proc_fops = &proc_net_dir_operations; |
| 198 | |
| 199 | return register_pernet_subsys(&proc_net_ns_ops); |
| 200 | } |