diff options
| -rw-r--r-- | fs/proc/proc_net.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c new file mode 100644 index 000000000000..45dde2f7034d --- /dev/null +++ b/fs/proc/proc_net.c @@ -0,0 +1,192 @@ +/* + * 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); +} + +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; +} + +void proc_net_remove(struct net *net, const char *name) +{ + remove_proc_entry(name, net->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 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 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 proc_net_ns_ops = { + .init = proc_net_ns_init, + .exit = proc_net_ns_exit, +}; + +int 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); +} |