/* -*- linux-c -*-
   * sysctl_net.c: sysctl interface to net subsystem.
   *
   * Begun April 1, 1996, Mike Shaver.
   * Added /proc/sys/net directories for each protocol family. [MS]
   *

   * Revision 1.2  1996/05/08  20:24:40  shaver
   * Added bits for NET_BRIDGE and the NET_IPV4_ARP stuff and
   * NET_IPV4_IP_FORWARD.
   *
   *
   */

  #include <linux/mm.h>

  #include <linux/export.h>

  #include <linux/sysctl.h>

  #include <linux/nsproxy.h>

  #include <net/sock.h>

  #ifdef CONFIG_INET

  #include <net/ip.h>

  #endif

  #ifdef CONFIG_NET

  #include <linux/if_ether.h>

  #endif
  
  #ifdef CONFIG_TR

  #include <linux/if_tr.h>

  #endif

  static struct ctl_table_set *

  net_ctl_header_lookup(struct ctl_table_root *root, struct nsproxy *namespaces)
  {

  	return &namespaces->net_ns->sysctls;
  }
  
  static int is_seen(struct ctl_table_set *set)
  {
  	return &current->nsproxy->net_ns->sysctls == set;

  }

  /* Return standard mode bits for table entry. */
  static int net_ctl_permissions(struct ctl_table_root *root,
  			       struct nsproxy *nsproxy,
  			       struct ctl_table *table)
  {
  	/* Allow network administrator to have same access as root. */
  	if (capable(CAP_NET_ADMIN)) {
  		int mode = (table->mode >> 6) & 7;
  		return (mode << 6) | (mode << 3) | mode;
  	}
  	return table->mode;
  }

  static struct ctl_table_root net_sysctl_root = {
  	.lookup = net_ctl_header_lookup,

  	.permissions = net_ctl_permissions,

  };

  static int net_ctl_ro_header_perms(struct ctl_table_root *root,
  		struct nsproxy *namespaces, struct ctl_table *table)
  {

  	if (net_eq(namespaces->net_ns, &init_net))

  		return table->mode;
  	else
  		return table->mode & ~0222;
  }
  
  static struct ctl_table_root net_sysctl_ro_root = {

  	.permissions = net_ctl_ro_header_perms,
  };

  static int __net_init sysctl_net_init(struct net *net)

  {

  	setup_sysctl_set(&net->sysctls,
  			 &net_sysctl_ro_root.default_set,
  			 is_seen);

  	return 0;
  }

  static void __net_exit sysctl_net_exit(struct net *net)

  {

  	WARN_ON(!list_empty(&net->sysctls.list));

  }
  
  static struct pernet_operations sysctl_pernet_ops = {
  	.init = sysctl_net_init,
  	.exit = sysctl_net_exit,
  };
  
  static __init int sysctl_init(void)
  {
  	int ret;
  	ret = register_pernet_subsys(&sysctl_pernet_ops);
  	if (ret)
  		goto out;
  	register_sysctl_root(&net_sysctl_root);

  	setup_sysctl_set(&net_sysctl_ro_root.default_set, NULL, NULL);

  	register_sysctl_root(&net_sysctl_ro_root);

  out:
  	return ret;
  }
  subsys_initcall(sysctl_init);
  
  struct ctl_table_header *register_net_sysctl_table(struct net *net,
  	const struct ctl_path *path, struct ctl_table *table)
  {
  	struct nsproxy namespaces;
  	namespaces = *current->nsproxy;
  	namespaces.net_ns = net;
  	return __register_sysctl_paths(&net_sysctl_root,
  					&namespaces, path, table);
  }
  EXPORT_SYMBOL_GPL(register_net_sysctl_table);

  struct ctl_table_header *register_net_sysctl_rotable(const
  		struct ctl_path *path, struct ctl_table *table)
  {
  	return __register_sysctl_paths(&net_sysctl_ro_root,
  			&init_nsproxy, path, table);
  }
  EXPORT_SYMBOL_GPL(register_net_sysctl_rotable);

  void unregister_net_sysctl_table(struct ctl_table_header *header)
  {

  	unregister_sysctl_table(header);

  }
  EXPORT_SYMBOL_GPL(unregister_net_sysctl_table);