kernel/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 #ifdef CONFIG_NETLINK_MMAP
  12 static int sk_diag_put_ring(struct netlink_ring *ring, int nl_type,
  13                             struct sk_buff *nlskb)
  14 {
  15         struct netlink_diag_ring ndr;
  16
  17         ndr.ndr_block_size = ring->pg_vec_pages << PAGE_SHIFT;
  18         ndr.ndr_block_nr   = ring->pg_vec_len;
  19         ndr.ndr_frame_size = ring->frame_size;
  20         ndr.ndr_frame_nr   = ring->frame_max + 1;
  21
  22         return nla_put(nlskb, nl_type, sizeof(ndr), &ndr);
  23 }
  24
  25 static int sk_diag_put_rings_cfg(struct sock *sk, struct sk_buff *nlskb)
  26 {
  27         struct netlink_sock *nlk = nlk_sk(sk);
  28         int ret;
  29
  30         mutex_lock(&nlk->pg_vec_lock);
  31         ret = sk_diag_put_ring(&nlk->rx_ring, NETLINK_DIAG_RX_RING, nlskb);
  32         if (!ret)
  33                 ret = sk_diag_put_ring(&nlk->tx_ring, NETLINK_DIAG_TX_RING,
  34                                        nlskb);
  35         mutex_unlock(&nlk->pg_vec_lock);
  36
  37         return ret;
  38 }
  39 #else
  40 static int sk_diag_put_rings_cfg(struct sock *sk, struct sk_buff *nlskb)
  41 {
  42         return 0;
  43 }
  44 #endif
  45
  46 static int sk_diag_dump_groups(struct sock *sk, struct sk_buff *nlskb)
  47 {
  48         struct netlink_sock *nlk = nlk_sk(sk);
  49
  50         if (nlk->groups == NULL)
  51                 return 0;
  52
  53         return nla_put(nlskb, NETLINK_DIAG_GROUPS, NLGRPSZ(nlk->ngroups),
  54                        nlk->groups);
  55 }
  56
  57 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
  58                         struct netlink_diag_req *req,
  59                         u32 portid, u32 seq, u32 flags, int sk_ino)
  60 {
  61         struct nlmsghdr *nlh;
  62         struct netlink_diag_msg *rep;
  63         struct netlink_sock *nlk = nlk_sk(sk);
  64
  65         nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep),
  66                         flags);
  67         if (!nlh)
  68                 return -EMSGSIZE;
  69
  70         rep = nlmsg_data(nlh);
  71         rep->ndiag_family       = AF_NETLINK;
  72         rep->ndiag_type         = sk->sk_type;
  73         rep->ndiag_protocol     = sk->sk_protocol;
  74         rep->ndiag_state        = sk->sk_state;
  75
  76         rep->ndiag_ino          = sk_ino;
  77         rep->ndiag_portid       = nlk->portid;
  78         rep->ndiag_dst_portid   = nlk->dst_portid;
  79         rep->ndiag_dst_group    = nlk->dst_group;
  80         sock_diag_save_cookie(sk, rep->ndiag_cookie);
  81
  82         if ((req->ndiag_show & NDIAG_SHOW_GROUPS) &&
  83             sk_diag_dump_groups(sk, skb))
  84                 goto out_nlmsg_trim;
  85
  86         if ((req->ndiag_show & NDIAG_SHOW_MEMINFO) &&
  87             sock_diag_put_meminfo(sk, skb, NETLINK_DIAG_MEMINFO))
  88                 goto out_nlmsg_trim;
  89
  90         if ((req->ndiag_show & NDIAG_SHOW_RING_CFG) &&
  91             sk_diag_put_rings_cfg(sk, skb))
  92                 goto out_nlmsg_trim;
  93
  94         nlmsg_end(skb, nlh);
  95         return 0;
  96
  97 out_nlmsg_trim:
  98         nlmsg_cancel(skb, nlh);
  99         return -EMSGSIZE;
 100 }
 101
 102 static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 103                                 int protocol, int s_num)
 104 {
 105         struct netlink_table *tbl = &nl_table[protocol];
 106         struct rhashtable *ht = &tbl->hash;
 107         const struct bucket_table *htbl = rht_dereference_rcu(ht->tbl, ht);
 108         struct net *net = sock_net(skb->sk);
 109         struct netlink_diag_req *req;
 110         struct netlink_sock *nlsk;
 111         struct sock *sk;
 112         int ret = 0, num = 0, i;
 113
 114         req = nlmsg_data(cb->nlh);
 115
 116         for (i = 0; i < htbl->size; i++) {
 117                 struct rhash_head *pos;
 118
 119                 rht_for_each_entry_rcu(nlsk, pos, htbl, i, node) {
 120                         sk = (struct sock *)nlsk;
 121
 122                         if (!net_eq(sock_net(sk), net))
 123                                 continue;
 124                         if (num < s_num) {
 125                                 num++;
 126                                 continue;
 127                         }
 128
 129                         if (sk_diag_fill(sk, skb, req,
 130                                          NETLINK_CB(cb->skb).portid,
 131                                          cb->nlh->nlmsg_seq,
 132                                          NLM_F_MULTI,
 133                                          sock_i_ino(sk)) < 0) {
 134                                 ret = 1;
 135                                 goto done;
 136                         }
 137
 138                         num++;
 139                 }
 140         }
 141
 142         sk_for_each_bound(sk, &tbl->mc_list) {
 143                 if (sk_hashed(sk))
 144                         continue;
 145                 if (!net_eq(sock_net(sk), net))
 146                         continue;
 147                 if (num < s_num) {
 148                         num++;
 149                         continue;
 150                 }
 151
 152                 if (sk_diag_fill(sk, skb, req,
 153                                  NETLINK_CB(cb->skb).portid,
 154                                  cb->nlh->nlmsg_seq,
 155                                  NLM_F_MULTI,
 156                                  sock_i_ino(sk)) < 0) {
 157                         ret = 1;
 158                         goto done;
 159                 }
 160                 num++;
 161         }
 162 done:
 163         cb->args[0] = num;
 164         cb->args[1] = protocol;
 165
 166         return ret;
 167 }
 168
 169 static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
 170 {
 171         struct netlink_diag_req *req;
 172         int s_num = cb->args[0];
 173
 174         req = nlmsg_data(cb->nlh);
 175
 176         rcu_read_lock();
 177         read_lock(&nl_table_lock);
 178
 179         if (req->sdiag_protocol == NDIAG_PROTO_ALL) {
 180                 int i;
 181
 182                 for (i = cb->args[1]; i < MAX_LINKS; i++) {
 183                         if (__netlink_diag_dump(skb, cb, i, s_num))
 184                                 break;
 185                         s_num = 0;
 186                 }
 187         } else {
 188                 if (req->sdiag_protocol >= MAX_LINKS) {
 189                         read_unlock(&nl_table_lock);
 190                         rcu_read_unlock();
 191                         return -ENOENT;
 192                 }
 193
 194                 __netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num);
 195         }
 196
 197         read_unlock(&nl_table_lock);
 198         rcu_read_unlock();
 199
 200         return skb->len;
 201 }
 202
 203 static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
 204 {
 205         int hdrlen = sizeof(struct netlink_diag_req);
 206         struct net *net = sock_net(skb->sk);
 207
 208         if (nlmsg_len(h) < hdrlen)
 209                 return -EINVAL;
 210
 211         if (h->nlmsg_flags & NLM_F_DUMP) {
 212                 struct netlink_dump_control c = {
 213                         .dump = netlink_diag_dump,
 214                 };
 215                 return netlink_dump_start(net->diag_nlsk, skb, h, &c);
 216         } else
 217                 return -EOPNOTSUPP;
 218 }
 219
 220 static const struct sock_diag_handler netlink_diag_handler = {
 221         .family = AF_NETLINK,
 222         .dump = netlink_diag_handler_dump,
 223 };
 224
 225 static int __init netlink_diag_init(void)
 226 {
 227         return sock_diag_register(&netlink_diag_handler);
 228 }
 229
 230 static void __exit netlink_diag_exit(void)
 231 {
 232         sock_diag_unregister(&netlink_diag_handler);
 233 }
 234
 235 module_init(netlink_diag_init);
 236 module_exit(netlink_diag_exit);
 237 MODULE_LICENSE("GPL");
 238 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 16 /* AF_NETLINK */);