net/ipv6/sysctl_net_ipv6.c

   1 /*
   2  * sysctl_net_ipv6.c: sysctl interface to net IPV6 subsystem.
   3  *
   4  * Changes:
   5  * YOSHIFUJI Hideaki @USAGI:    added icmp sysctl table.
   6  */
   7
   8 #include <linux/mm.h>
   9 #include <linux/sysctl.h>
  10 #include <linux/in6.h>
  11 #include <linux/ipv6.h>
  12 #include <net/ndisc.h>
  13 #include <net/ipv6.h>
  14 #include <net/addrconf.h>
  15 #include <net/inet_frag.h>
  16
  17 static ctl_table ipv6_table_template[] = {
  18         {
  19                 .ctl_name       = NET_IPV6_ROUTE,
  20                 .procname       = "route",
  21                 .maxlen         = 0,
  22                 .mode           = 0555,
  23                 .child          = ipv6_route_table_template
  24         },
  25         {
  26                 .ctl_name       = NET_IPV6_ICMP,
  27                 .procname       = "icmp",
  28                 .maxlen         = 0,
  29                 .mode           = 0555,
  30                 .child          = ipv6_icmp_table_template
  31         },
  32         {
  33                 .ctl_name       = NET_IPV6_BINDV6ONLY,
  34                 .procname       = "bindv6only",
  35                 .data           = &init_net.ipv6.sysctl.bindv6only,
  36                 .maxlen         = sizeof(int),
  37                 .mode           = 0644,
  38                 .proc_handler   = &proc_dointvec
  39         },
  40         {
  41                 .ctl_name       = NET_IPV6_MLD_MAX_MSF,
  42                 .procname       = "mld_max_msf",
  43                 .data           = &sysctl_mld_max_msf,
  44                 .maxlen         = sizeof(int),
  45                 .mode           = 0644,
  46                 .proc_handler   = &proc_dointvec
  47         },
  48         { .ctl_name = 0 }
  49 };
  50
  51 struct ctl_path net_ipv6_ctl_path[] = {
  52         { .procname = "net", .ctl_name = CTL_NET, },
  53         { .procname = "ipv6", .ctl_name = NET_IPV6, },
  54         { },
  55 };
  56 EXPORT_SYMBOL_GPL(net_ipv6_ctl_path);
  57
  58 static int ipv6_sysctl_net_init(struct net *net)
  59 {
  60         struct ctl_table *ipv6_table;
  61         struct ctl_table *ipv6_route_table;
  62         struct ctl_table *ipv6_icmp_table;
  63         int err;
  64
  65         err = -ENOMEM;
  66         ipv6_table = kmemdup(ipv6_table_template, sizeof(ipv6_table_template),
  67                              GFP_KERNEL);
  68         if (!ipv6_table)
  69                 goto out;
  70
  71         ipv6_route_table = ipv6_route_sysctl_init(net);
  72         if (!ipv6_route_table)
  73                 goto out_ipv6_table;
  74         ipv6_table[0].child = ipv6_route_table;
  75
  76         ipv6_icmp_table = ipv6_icmp_sysctl_init(net);
  77         if (!ipv6_icmp_table)
  78                 goto out_ipv6_route_table;
  79         ipv6_table[1].child = ipv6_icmp_table;
  80
  81         ipv6_table[2].data = &net->ipv6.sysctl.bindv6only;
  82
  83         /* We don't want this value to be per namespace, it should be global
  84            to all namespaces, so make it read-only when we are not in the
  85            init network namespace */
  86         if (net != &init_net)
  87                 ipv6_table[3].mode = 0444;
  88
  89         net->ipv6.sysctl.table = register_net_sysctl_table(net, net_ipv6_ctl_path,
  90                                                            ipv6_table);
  91         if (!net->ipv6.sysctl.table)
  92                 goto out_ipv6_icmp_table;
  93
  94         err = 0;
  95 out:
  96         return err;
  97
  98 out_ipv6_icmp_table:
  99         kfree(ipv6_icmp_table);
 100 out_ipv6_route_table:
 101         kfree(ipv6_route_table);
 102 out_ipv6_table:
 103         kfree(ipv6_table);
 104         goto out;
 105 }
 106
 107 static void ipv6_sysctl_net_exit(struct net *net)
 108 {
 109         struct ctl_table *ipv6_table;
 110         struct ctl_table *ipv6_route_table;
 111         struct ctl_table *ipv6_icmp_table;
 112
 113         ipv6_table = net->ipv6.sysctl.table->ctl_table_arg;
 114         ipv6_route_table = ipv6_table[0].child;
 115         ipv6_icmp_table = ipv6_table[1].child;
 116
 117         unregister_net_sysctl_table(net->ipv6.sysctl.table);
 118
 119         kfree(ipv6_table);
 120         kfree(ipv6_route_table);
 121         kfree(ipv6_icmp_table);
 122 }
 123
 124 static struct pernet_operations ipv6_sysctl_net_ops = {
 125         .init = ipv6_sysctl_net_init,
 126         .exit = ipv6_sysctl_net_exit,
 127 };
 128
 129 int ipv6_sysctl_register(void)
 130 {
 131         return register_pernet_subsys(&ipv6_sysctl_net_ops);
 132 }
 133
 134 void ipv6_sysctl_unregister(void)
 135 {
 136         unregister_pernet_subsys(&ipv6_sysctl_net_ops);
 137 }