/* * linux/fs/proc/net.c * * Copyright (C) 2007 * * Author: Eric Biederman <ebiederm@xmission.com> * * proc net directory handling functions */ #include <asm/uaccess.h> #include <linux/errno.h> #include <linux/time.h> #include <linux/proc_fs.h> #include <linux/stat.h> #include <linux/init.h> #include <linux/sched.h> #include <linux/module.h> #include <linux/bitops.h> #include <linux/smp_lock.h> #include <linux/mount.h> #include <linux/nsproxy.h> #include <net/net_namespace.h> #include "internal.h" struct proc_dir_entry *proc_net_create(struct net *net, const char *name, mode_t mode, get_info_t *get_info) { return create_proc_info_entry(name,mode, net->proc_net, get_info); } EXPORT_SYMBOL_GPL(proc_net_create); struct proc_dir_entry *proc_net_fops_create(struct net *net, const char *name, mode_t mode, const struct file_operations *fops) { struct proc_dir_entry *res; res = create_proc_entry(name, mode, net->proc_net); if (res) res->proc_fops = fops; return res; } EXPORT_SYMBOL_GPL(proc_net_fops_create); void proc_net_remove(struct net *net, const char *name) { remove_proc_entry(name, net->proc_net); } EXPORT_SYMBOL_GPL(proc_net_remove); struct net *get_proc_net(const struct inode *inode) { return maybe_get_net(PDE_NET(PDE(inode))); } EXPORT_SYMBOL_GPL(get_proc_net); static struct proc_dir_entry *proc_net_shadow; static struct dentry *proc_net_shadow_dentry(struct dentry *parent, struct proc_dir_entry *de) { struct dentry *shadow = NULL; struct inode *inode; if (!de) goto out; de_get(de); inode = proc_get_inode(parent->d_inode->i_sb, de->low_ino, de); if (!inode) goto out_de_put; shadow = d_alloc_name(parent, de->name); if (!shadow) goto out_iput; shadow->d_op = parent->d_op; /* proc_dentry_operations */ d_instantiate(shadow, inode); out: return shadow; out_iput: iput(inode); out_de_put: de_put(de); goto out; } static void *proc_net_follow_link(struct dentry *parent, struct nameidata *nd) { struct net *net = current->nsproxy->net_ns; struct dentry *shadow; shadow = proc_net_shadow_dentry(parent, net->proc_net); if (!shadow) return ERR_PTR(-ENOENT); dput(nd->dentry); /* My dentry count is 1 and that should be enough as the * shadow dentry is thrown away immediately. */ nd->dentry = shadow; return NULL; } static struct dentry *proc_net_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) { struct net *net = current->nsproxy->net_ns; struct dentry *shadow; shadow = proc_net_shadow_dentry(nd->dentry, net->proc_net); if (!shadow) return ERR_PTR(-ENOENT); dput(nd->dentry); nd->dentry = shadow; return shadow->d_inode->i_op->lookup(shadow->d_inode, dentry, nd); } static int proc_net_setattr(struct dentry *dentry, struct iattr *iattr) { struct net *net = current->nsproxy->net_ns; struct dentry *shadow; int ret; shadow = proc_net_shadow_dentry(dentry->d_parent, net->proc_net); if (!shadow) return -ENOENT; ret = shadow->d_inode->i_op->setattr(shadow, iattr); dput(shadow); return ret; } static const struct file_operations proc_net_dir_operations = { .read = generic_read_dir, }; static struct inode_operations proc_net_dir_inode_operations = { .follow_link = proc_net_follow_link, .lookup = proc_net_lookup, .setattr = proc_net_setattr, }; static __net_init int proc_net_ns_init(struct net *net) { struct proc_dir_entry *root, *netd, *net_statd; int err; err = -ENOMEM; root = kzalloc(sizeof(*root), GFP_KERNEL); if (!root) goto out; err = -EEXIST; netd = proc_mkdir("net", root); if (!netd) goto free_root; err = -EEXIST; net_statd = proc_mkdir("stat", netd); if (!net_statd) goto free_net; root->data = net; netd->data = net; net_statd->data = net; net->proc_net_root = root; net->proc_net = netd; net->proc_net_stat = net_statd; err = 0; out: return err; free_net: remove_proc_entry("net", root); free_root: kfree(root); goto out; } static __net_exit void proc_net_ns_exit(struct net *net) { remove_proc_entry("stat", net->proc_net); remove_proc_entry("net", net->proc_net_root); kfree(net->proc_net_root); } struct pernet_operations __net_initdata proc_net_ns_ops = { .init = proc_net_ns_init, .exit = proc_net_ns_exit, }; int __init proc_net_init(void) { proc_net_shadow = proc_mkdir("net", NULL); proc_net_shadow->proc_iops = &proc_net_dir_inode_operations; proc_net_shadow->proc_fops = &proc_net_dir_operations; return register_pernet_subsys(&proc_net_ns_ops); }