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
   8 #include "af_netlink.h"
   9
  10 static int sk_diag_put_ring(struct netlink_ring *ring, int nl_type,
  11                             struct sk_buff *nlskb)
  12 {
  13         struct netlink_diag_ring ndr;
  14
  15         ndr.ndr_block_size = ring->pg_vec_pages << PAGE_SHIFT;
  16         ndr.ndr_block_nr   = ring->pg_vec_len;
  17         ndr.ndr_frame_size = ring->frame_size;
  18         ndr.ndr_frame_nr   = ring->frame_max + 1;
  19
  20         return nla_put(nlskb, nl_type, sizeof(ndr), &ndr);
  21 }
  22
  23 static int sk_diag_put_rings_cfg(struct sock *sk, struct sk_buff *nlskb)
  24 {
  25         struct netlink_sock *nlk = nlk_sk(sk);
  26         int ret;
  27
  28         mutex_lock(&nlk->pg_vec_lock);
  29         ret = sk_diag_put_ring(&nlk->rx_ring, NETLINK_DIAG_RX_RING, nlskb);
  30         if (!ret)
  31                 ret = sk_diag_put_ring(&nlk->tx_ring, NETLINK_DIAG_TX_RING,
  32                                        nlskb);
  33         mutex_unlock(&nlk->pg_vec_lock);
  34
  35         return ret;
  36 }
  37
  38 static int sk_diag_dump_groups(struct sock *sk, struct sk_buff *nlskb)
  39 {
  40         struct netlink_sock *nlk = nlk_sk(sk);
  41
  42         if (nlk->groups == NULL)
  43                 return 0;
  44
  45         return nla_put(nlskb, NETLINK_DIAG_GROUPS, NLGRPSZ(nlk->ngroups),
  46                        nlk->groups);
  47 }
  48
  49 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
  50                         struct netlink_diag_req *req,
  51                         u32 portid, u32 seq, u32 flags, int sk_ino)
  52 {
  53         struct nlmsghdr *nlh;
  54         struct netlink_diag_msg *rep;
  55         struct netlink_sock *nlk = nlk_sk(sk);
  56
  57         nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep),
  58                         flags);
  59         if (!nlh)
  60                 return -EMSGSIZE;
  61
  62         rep = nlmsg_data(nlh);
  63         rep->ndiag_family       = AF_NETLINK;
  64         rep->ndiag_type         = sk->sk_type;
  65         rep->ndiag_protocol     = sk->sk_protocol;
  66         rep->ndiag_state        = sk->sk_state;
  67
  68         rep->ndiag_ino          = sk_ino;
  69         rep->ndiag_portid       = nlk->portid;
  70         rep->ndiag_dst_portid   = nlk->dst_portid;
  71         rep->ndiag_dst_group    = nlk->dst_group;
  72         sock_diag_save_cookie(sk, rep->ndiag_cookie);
  73
  74         if ((req->ndiag_show & NDIAG_SHOW_GROUPS) &&
  75             sk_diag_dump_groups(sk, skb))
  76                 goto out_nlmsg_trim;
  77
  78         if ((req->ndiag_show & NDIAG_SHOW_MEMINFO) &&
  79             sock_diag_put_meminfo(sk, skb, NETLINK_DIAG_MEMINFO))
  80                 goto out_nlmsg_trim;
  81
  82         if ((req->ndiag_show & NDIAG_SHOW_RING_CFG) &&
  83             sk_diag_put_rings_cfg(sk, skb))
  84                 goto out_nlmsg_trim;
  85
  86         return nlmsg_end(skb, nlh);
  87
  88 out_nlmsg_trim:
  89         nlmsg_cancel(skb, nlh);
  90         return -EMSGSIZE;
  91 }
  92
  93 static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
  94                                 int protocol, int s_num)
  95 {
  96         struct netlink_table *tbl = &nl_table[protocol];
  97         struct nl_portid_hash *hash = &tbl->hash;
  98         struct net *net = sock_net(skb->sk);
  99         struct netlink_diag_req *req;
 100         struct sock *sk;
 101         int ret = 0, num = 0, i;
 102
 103         req = nlmsg_data(cb->nlh);
 104
 105         for (i = 0; i <= hash->mask; i++) {
 106                 sk_for_each(sk, &hash->table[i]) {
 107                         if (!net_eq(sock_net(sk), net))
 108                                 continue;
 109                         if (num < s_num) {
 110                                 num++;
 111                                 continue;
 112                         }
 113
 114                         if (sk_diag_fill(sk, skb, req,
 115                                          NETLINK_CB(cb->skb).portid,
 116                                          cb->nlh->nlmsg_seq,
 117                                          NLM_F_MULTI,
 118                                          sock_i_ino(sk)) < 0) {
 119                                 ret = 1;
 120                                 goto done;
 121                         }
 122
 123                         num++;
 124                 }
 125         }
 126
 127         sk_for_each_bound(sk, &tbl->mc_list) {
 128                 if (sk_hashed(sk))
 129                         continue;
 130                 if (!net_eq(sock_net(sk), net))
 131                         continue;
 132                 if (num < s_num) {
 133                         num++;
 134                         continue;
 135                 }
 136
 137                 if (sk_diag_fill(sk, skb, req,
 138                                  NETLINK_CB(cb->skb).portid,
 139                                  cb->nlh->nlmsg_seq,
 140                                  NLM_F_MULTI,
 141                                  sock_i_ino(sk)) < 0) {
 142                         ret = 1;
 143                         goto done;
 144                 }
 145                 num++;
 146         }
 147 done:
 148         cb->args[0] = num;
 149         cb->args[1] = protocol;
 150
 151         return ret;
 152 }
 153
 154 static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
 155 {
 156         struct netlink_diag_req *req;
 157         int s_num = cb->args[0];
 158
 159         req = nlmsg_data(cb->nlh);
 160
 161         read_lock(&nl_table_lock);
 162
 163         if (req->sdiag_protocol == NDIAG_PROTO_ALL) {
 164                 int i;
 165
 166                 for (i = cb->args[1]; i < MAX_LINKS; i++) {
 167                         if (__netlink_diag_dump(skb, cb, i, s_num))
 168                                 break;
 169                         s_num = 0;
 170                 }
 171         } else {
 172                 if (req->sdiag_protocol >= MAX_LINKS) {
 173                         read_unlock(&nl_table_lock);
 174                         return -ENOENT;
 175                 }
 176
 177                 __netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num);
 178         }
 179
 180         read_unlock(&nl_table_lock);
 181
 182         return skb->len;
 183 }
 184
 185 static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
 186 {
 187         int hdrlen = sizeof(struct netlink_diag_req);
 188         struct net *net = sock_net(skb->sk);
 189
 190         if (nlmsg_len(h) < hdrlen)
 191                 return -EINVAL;
 192
 193         if (h->nlmsg_flags & NLM_F_DUMP) {
 194                 struct netlink_dump_control c = {
 195                         .dump = netlink_diag_dump,
 196                 };
 197                 return netlink_dump_start(net->diag_nlsk, skb, h, &c);
 198         } else
 199                 return -EOPNOTSUPP;
 200 }
 201
 202 static const struct sock_diag_handler netlink_diag_handler = {
 203         .family = AF_NETLINK,
 204         .dump = netlink_diag_handler_dump,
 205 };
 206
 207 static int __init netlink_diag_init(void)
 208 {
 209         return sock_diag_register(&netlink_diag_handler);
 210 }
 211
 212 static void __exit netlink_diag_exit(void)
 213 {
 214         sock_diag_unregister(&netlink_diag_handler);
 215 }
 216
 217 module_init(netlink_diag_init);
 218 module_exit(netlink_diag_exit);
 219 MODULE_LICENSE("GPL");
 220 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 16 /* AF_NETLINK */);