net/netlink/diag.c

   1 #include <linux/module.h>
   2
   3 #include <net/sock.h>
   4 #include <linux/netlink.h>
   5 #include <linux/sock_diag.h>
   6 #include <linux/netlink_diag.h>
   7 #include <linux/rhashtable.h>
   8
   9 #include "af_netlink.h"
  10
  11 static int sk_diag_dump_groups(struct sock *sk, struct sk_buff *nlskb)
  12 {
  13         struct netlink_sock *nlk = nlk_sk(sk);
  14
  15         if (nlk->groups == NULL)
  16                 return 0;
  17
  18         return nla_put(nlskb, NETLINK_DIAG_GROUPS, NLGRPSZ(nlk->ngroups),
  19                        nlk->groups);
  20 }
  21
  22 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
  23                         struct netlink_diag_req *req,
  24                         u32 portid, u32 seq, u32 flags, int sk_ino)
  25 {
  26         struct nlmsghdr *nlh;
  27         struct netlink_diag_msg *rep;
  28         struct netlink_sock *nlk = nlk_sk(sk);
  29
  30         nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep),
  31                         flags);
  32         if (!nlh)
  33                 return -EMSGSIZE;
  34
  35         rep = nlmsg_data(nlh);
  36         rep->ndiag_family       = AF_NETLINK;
  37         rep->ndiag_type         = sk->sk_type;
  38         rep->ndiag_protocol     = sk->sk_protocol;
  39         rep->ndiag_state        = sk->sk_state;
  40
  41         rep->ndiag_ino          = sk_ino;
  42         rep->ndiag_portid       = nlk->portid;
  43         rep->ndiag_dst_portid   = nlk->dst_portid;
  44         rep->ndiag_dst_group    = nlk->dst_group;
  45         sock_diag_save_cookie(sk, rep->ndiag_cookie);
  46
  47         if ((req->ndiag_show & NDIAG_SHOW_GROUPS) &&
  48             sk_diag_dump_groups(sk, skb))
  49                 goto out_nlmsg_trim;
  50
  51         if ((req->ndiag_show & NDIAG_SHOW_MEMINFO) &&
  52             sock_diag_put_meminfo(sk, skb, NETLINK_DIAG_MEMINFO))
  53                 goto out_nlmsg_trim;
  54
  55         nlmsg_end(skb, nlh);
  56         return 0;
  57
  58 out_nlmsg_trim:
  59         nlmsg_cancel(skb, nlh);
  60         return -EMSGSIZE;
  61 }
  62
  63 static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
  64                                 int protocol, int s_num)
  65 {
  66         struct netlink_table *tbl = &nl_table[protocol];
  67         struct rhashtable *ht = &tbl->hash;
  68         const struct bucket_table *htbl = rht_dereference_rcu(ht->tbl, ht);
  69         struct net *net = sock_net(skb->sk);
  70         struct netlink_diag_req *req;
  71         struct netlink_sock *nlsk;
  72         struct sock *sk;
  73         int ret = 0, num = 0, i;
  74
  75         req = nlmsg_data(cb->nlh);
  76
  77         for (i = 0; i < htbl->size; i++) {
  78                 struct rhash_head *pos;
  79
  80                 rht_for_each_entry_rcu(nlsk, pos, htbl, i, node) {
  81                         sk = (struct sock *)nlsk;
  82
  83                         if (!net_eq(sock_net(sk), net))
  84                                 continue;
  85                         if (num < s_num) {
  86                                 num++;
  87                                 continue;
  88                         }
  89
  90                         if (sk_diag_fill(sk, skb, req,
  91                                          NETLINK_CB(cb->skb).portid,
  92                                          cb->nlh->nlmsg_seq,
  93                                          NLM_F_MULTI,
  94                                          sock_i_ino(sk)) < 0) {
  95                                 ret = 1;
  96                                 goto done;
  97                         }
  98
  99                         num++;
 100                 }
 101         }
 102
 103         sk_for_each_bound(sk, &tbl->mc_list) {
 104                 if (sk_hashed(sk))
 105                         continue;
 106                 if (!net_eq(sock_net(sk), net))
 107                         continue;
 108                 if (num < s_num) {
 109                         num++;
 110                         continue;
 111                 }
 112
 113                 if (sk_diag_fill(sk, skb, req,
 114                                  NETLINK_CB(cb->skb).portid,
 115                                  cb->nlh->nlmsg_seq,
 116                                  NLM_F_MULTI,
 117                                  sock_i_ino(sk)) < 0) {
 118                         ret = 1;
 119                         goto done;
 120                 }
 121                 num++;
 122         }
 123 done:
 124         cb->args[0] = num;
 125         cb->args[1] = protocol;
 126
 127         return ret;
 128 }
 129
 130 static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
 131 {
 132         struct netlink_diag_req *req;
 133         int s_num = cb->args[0];
 134
 135         req = nlmsg_data(cb->nlh);
 136
 137         rcu_read_lock();
 138         read_lock(&nl_table_lock);
 139
 140         if (req->sdiag_protocol == NDIAG_PROTO_ALL) {
 141                 int i;
 142
 143                 for (i = cb->args[1]; i < MAX_LINKS; i++) {
 144                         if (__netlink_diag_dump(skb, cb, i, s_num))
 145                                 break;
 146                         s_num = 0;
 147                 }
 148         } else {
 149                 if (req->sdiag_protocol >= MAX_LINKS) {
 150                         read_unlock(&nl_table_lock);
 151                         rcu_read_unlock();
 152                         return -ENOENT;
 153                 }
 154
 155                 __netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num);
 156         }
 157
 158         read_unlock(&nl_table_lock);
 159         rcu_read_unlock();
 160
 161         return skb->len;
 162 }
 163
 164 static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
 165 {
 166         int hdrlen = sizeof(struct netlink_diag_req);
 167         struct net *net = sock_net(skb->sk);
 168
 169         if (nlmsg_len(h) < hdrlen)
 170                 return -EINVAL;
 171
 172         if (h->nlmsg_flags & NLM_F_DUMP) {
 173                 struct netlink_dump_control c = {
 174                         .dump = netlink_diag_dump,
 175                 };
 176                 return netlink_dump_start(net->diag_nlsk, skb, h, &c);
 177         } else
 178                 return -EOPNOTSUPP;
 179 }
 180
 181 static const struct sock_diag_handler netlink_diag_handler = {
 182         .family = AF_NETLINK,
 183         .dump = netlink_diag_handler_dump,
 184 };
 185
 186 static int __init netlink_diag_init(void)
 187 {
 188         return sock_diag_register(&netlink_diag_handler);
 189 }
 190
 191 static void __exit netlink_diag_exit(void)
 192 {
 193         sock_diag_unregister(&netlink_diag_handler);
 194 }
 195
 196 module_init(netlink_diag_init);
 197 module_exit(netlink_diag_exit);
 198 MODULE_LICENSE("GPL");
 199 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 16 /* AF_NETLINK */);