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 #include <linux/seq_file.h> 26 27 #include "internal.h" 28 29 30 int seq_open_net(struct inode *ino, struct file *f, 31 const struct seq_operations *ops, int size) 32 { 33 struct net *net; 34 struct seq_net_private *p; 35 36 BUG_ON(size < sizeof(*p)); 37 38 net = get_proc_net(ino); 39 if (net == NULL) 40 return -ENXIO; 41 42 p = __seq_open_private(f, ops, size); 43 if (p == NULL) { 44 put_net(net); 45 return -ENOMEM; 46 } 47 p->net = net; 48 return 0; 49 } 50 EXPORT_SYMBOL_GPL(seq_open_net); 51 52 int seq_release_net(struct inode *ino, struct file *f) 53 { 54 struct seq_file *seq; 55 struct seq_net_private *p; 56 57 seq = f->private_data; 58 p = seq->private; 59 60 put_net(p->net); 61 seq_release_private(ino, f); 62 return 0; 63 } 64 EXPORT_SYMBOL_GPL(seq_release_net); 65 66 67 struct proc_dir_entry *proc_net_fops_create(struct net *net, 68 const char *name, mode_t mode, const struct file_operations *fops) 69 { 70 return proc_create(name, mode, net->proc_net, fops); 71 } 72 EXPORT_SYMBOL_GPL(proc_net_fops_create); 73 74 void proc_net_remove(struct net *net, const char *name) 75 { 76 remove_proc_entry(name, net->proc_net); 77 } 78 EXPORT_SYMBOL_GPL(proc_net_remove); 79 80 struct net *get_proc_net(const struct inode *inode) 81 { 82 return maybe_get_net(PDE_NET(PDE(inode))); 83 } 84 EXPORT_SYMBOL_GPL(get_proc_net); 85 86 static struct proc_dir_entry *shadow_pde; 87 88 static struct proc_dir_entry *proc_net_shadow(struct task_struct *task, 89 struct proc_dir_entry *de) 90 { 91 return task->nsproxy->net_ns->proc_net; 92 } 93 94 struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name, 95 struct proc_dir_entry *parent) 96 { 97 struct proc_dir_entry *pde; 98 pde = proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent); 99 if (pde != NULL) 100 pde->data = net; 101 return pde; 102 } 103 EXPORT_SYMBOL_GPL(proc_net_mkdir); 104 105 static __net_init int proc_net_ns_init(struct net *net) 106 { 107 struct proc_dir_entry *root, *netd, *net_statd; 108 int err; 109 110 err = -ENOMEM; 111 root = kzalloc(sizeof(*root), GFP_KERNEL); 112 if (!root) 113 goto out; 114 115 err = -EEXIST; 116 netd = proc_net_mkdir(net, "net", root); 117 if (!netd) 118 goto free_root; 119 120 err = -EEXIST; 121 net_statd = proc_net_mkdir(net, "stat", netd); 122 if (!net_statd) 123 goto free_net; 124 125 root->data = net; 126 127 net->proc_net_root = root; 128 net->proc_net = netd; 129 net->proc_net_stat = net_statd; 130 err = 0; 131 132 out: 133 return err; 134 free_net: 135 remove_proc_entry("net", root); 136 free_root: 137 kfree(root); 138 goto out; 139 } 140 141 static __net_exit void proc_net_ns_exit(struct net *net) 142 { 143 remove_proc_entry("stat", net->proc_net); 144 remove_proc_entry("net", net->proc_net_root); 145 kfree(net->proc_net_root); 146 } 147 148 static struct pernet_operations __net_initdata proc_net_ns_ops = { 149 .init = proc_net_ns_init, 150 .exit = proc_net_ns_exit, 151 }; 152 153 int __init proc_net_init(void) 154 { 155 shadow_pde = proc_mkdir("net", NULL); 156 shadow_pde->shadow_proc = proc_net_shadow; 157 158 return register_pernet_subsys(&proc_net_ns_ops); 159 } 160