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 struct proc_dir_entry *res; 71 72 res = create_proc_entry(name, mode, net->proc_net); 73 if (res) 74 res->proc_fops = fops; 75 return res; 76 } 77 EXPORT_SYMBOL_GPL(proc_net_fops_create); 78 79 void proc_net_remove(struct net *net, const char *name) 80 { 81 remove_proc_entry(name, net->proc_net); 82 } 83 EXPORT_SYMBOL_GPL(proc_net_remove); 84 85 struct net *get_proc_net(const struct inode *inode) 86 { 87 return maybe_get_net(PDE_NET(PDE(inode))); 88 } 89 EXPORT_SYMBOL_GPL(get_proc_net); 90 91 static struct proc_dir_entry *shadow_pde; 92 93 static struct proc_dir_entry *proc_net_shadow(struct task_struct *task, 94 struct proc_dir_entry *de) 95 { 96 return task->nsproxy->net_ns->proc_net; 97 } 98 99 struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name, 100 struct proc_dir_entry *parent) 101 { 102 struct proc_dir_entry *pde; 103 pde = proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent); 104 if (pde != NULL) 105 pde->data = net; 106 return pde; 107 } 108 EXPORT_SYMBOL_GPL(proc_net_mkdir); 109 110 static __net_init int proc_net_ns_init(struct net *net) 111 { 112 struct proc_dir_entry *root, *netd, *net_statd; 113 int err; 114 115 err = -ENOMEM; 116 root = kzalloc(sizeof(*root), GFP_KERNEL); 117 if (!root) 118 goto out; 119 120 err = -EEXIST; 121 netd = proc_net_mkdir(net, "net", root); 122 if (!netd) 123 goto free_root; 124 125 err = -EEXIST; 126 net_statd = proc_net_mkdir(net, "stat", netd); 127 if (!net_statd) 128 goto free_net; 129 130 root->data = net; 131 132 net->proc_net_root = root; 133 net->proc_net = netd; 134 net->proc_net_stat = net_statd; 135 err = 0; 136 137 out: 138 return err; 139 free_net: 140 remove_proc_entry("net", root); 141 free_root: 142 kfree(root); 143 goto out; 144 } 145 146 static __net_exit void proc_net_ns_exit(struct net *net) 147 { 148 remove_proc_entry("stat", net->proc_net); 149 remove_proc_entry("net", net->proc_net_root); 150 kfree(net->proc_net_root); 151 } 152 153 static struct pernet_operations __net_initdata proc_net_ns_ops = { 154 .init = proc_net_ns_init, 155 .exit = proc_net_ns_exit, 156 }; 157 158 int __init proc_net_init(void) 159 { 160 shadow_pde = proc_mkdir("net", NULL); 161 shadow_pde->shadow_proc = proc_net_shadow; 162 163 return register_pernet_subsys(&proc_net_ns_ops); 164 } 165