net/ipv4/udp_diag.c

   1 /*
   2  * udp_diag.c   Module for monitoring UDP transport protocols sockets.
   3  *
   4  * Authors:     Pavel Emelyanov, <xemul@parallels.com>
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License
   8  *      as published by the Free Software Foundation; either version
   9  *      2 of the License, or (at your option) any later version.
  10  */
  11
  12
  13 #include <linux/module.h>
  14 #include <linux/inet_diag.h>
  15 #include <linux/udp.h>
  16 #include <net/udp.h>
  17 #include <net/udplite.h>
  18 #include <linux/inet_diag.h>
  19 #include <linux/sock_diag.h>
  20
  21 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
  22                 struct netlink_callback *cb, struct inet_diag_req *req,
  23                 struct nlattr *bc)
  24 {
  25         if (!inet_diag_bc_sk(bc, sk))
  26                 return 0;
  27
  28         return inet_sk_diag_fill(sk, NULL, skb, req, NETLINK_CB(cb->skb).pid,
  29                         cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
  30 }
  31
  32 static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
  33                 const struct nlmsghdr *nlh, struct inet_diag_req *req)
  34 {
  35         int err = -EINVAL;
  36         struct sock *sk;
  37         struct sk_buff *rep;
  38
  39         if (req->sdiag_family == AF_INET)
  40                 sk = __udp4_lib_lookup(&init_net,
  41                                 req->id.idiag_src[0], req->id.idiag_sport,
  42                                 req->id.idiag_dst[0], req->id.idiag_dport,
  43                                 req->id.idiag_if, tbl);
  44         else if (req->sdiag_family == AF_INET6)
  45                 sk = __udp6_lib_lookup(&init_net,
  46                                 (struct in6_addr *)req->id.idiag_src,
  47                                 req->id.idiag_sport,
  48                                 (struct in6_addr *)req->id.idiag_dst,
  49                                 req->id.idiag_dport,
  50                                 req->id.idiag_if, tbl);
  51         else
  52                 goto out_nosk;
  53
  54         err = -ENOENT;
  55         if (sk == NULL)
  56                 goto out_nosk;
  57
  58         err = inet_diag_check_cookie(sk, req);
  59         if (err)
  60                 goto out;
  61
  62         err = -ENOMEM;
  63         rep = alloc_skb(NLMSG_SPACE((sizeof(struct inet_diag_msg) +
  64                                      sizeof(struct inet_diag_meminfo) +
  65                                      64)), GFP_KERNEL);
  66         if (!rep)
  67                 goto out;
  68
  69         err = inet_sk_diag_fill(sk, NULL, rep, req,
  70                            NETLINK_CB(in_skb).pid,
  71                            nlh->nlmsg_seq, 0, nlh);
  72         if (err < 0) {
  73                 WARN_ON(err == -EMSGSIZE);
  74                 kfree_skb(rep);
  75                 goto out;
  76         }
  77         err = netlink_unicast(sock_diag_nlsk, rep, NETLINK_CB(in_skb).pid,
  78                               MSG_DONTWAIT);
  79         if (err > 0)
  80                 err = 0;
  81 out:
  82         if (sk)
  83                 sock_put(sk);
  84 out_nosk:
  85         return err;
  86 }
  87
  88 static void udp_dump(struct udp_table *table, struct sk_buff *skb, struct netlink_callback *cb,
  89                 struct inet_diag_req *r, struct nlattr *bc)
  90 {
  91         int num, s_num, slot, s_slot;
  92
  93         s_slot = cb->args[0];
  94         num = s_num = cb->args[1];
  95
  96         for (slot = s_slot; slot <= table->mask; num = s_num = 0, slot++) {
  97                 struct sock *sk;
  98                 struct hlist_nulls_node *node;
  99                 struct udp_hslot *hslot = &table->hash[slot];
 100
 101                 if (hlist_nulls_empty(&hslot->head))
 102                         continue;
 103
 104                 spin_lock_bh(&hslot->lock);
 105                 sk_nulls_for_each(sk, node, &hslot->head) {
 106                         struct inet_sock *inet = inet_sk(sk);
 107
 108                         if (num < s_num)
 109                                 goto next;
 110                         if (!(r->idiag_states & (1 << sk->sk_state)))
 111                                 goto next;
 112                         if (r->sdiag_family != AF_UNSPEC &&
 113                                         sk->sk_family != r->sdiag_family)
 114                                 goto next;
 115                         if (r->id.idiag_sport != inet->inet_sport &&
 116                             r->id.idiag_sport)
 117                                 goto next;
 118                         if (r->id.idiag_dport != inet->inet_dport &&
 119                             r->id.idiag_dport)
 120                                 goto next;
 121
 122                         if (sk_diag_dump(sk, skb, cb, r, bc) < 0) {
 123                                 spin_unlock_bh(&hslot->lock);
 124                                 goto done;
 125                         }
 126 next:
 127                         num++;
 128                 }
 129                 spin_unlock_bh(&hslot->lock);
 130         }
 131 done:
 132         cb->args[0] = slot;
 133         cb->args[1] = num;
 134 }
 135
 136 static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 137                 struct inet_diag_req *r, struct nlattr *bc)
 138 {
 139         udp_dump(&udp_table, skb, cb, r, bc);
 140 }
 141
 142 static int udp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
 143                 struct inet_diag_req *req)
 144 {
 145         return udp_dump_one(&udp_table, in_skb, nlh, req);
 146 }
 147
 148 static const struct inet_diag_handler udp_diag_handler = {
 149         .dump            = udp_diag_dump,
 150         .dump_one        = udp_diag_dump_one,
 151         .idiag_type      = IPPROTO_UDP,
 152 };
 153
 154 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 155                 struct inet_diag_req *r, struct nlattr *bc)
 156 {
 157         udp_dump(&udplite_table, skb, cb, r, bc);
 158 }
 159
 160 static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
 161                 struct inet_diag_req *req)
 162 {
 163         return udp_dump_one(&udplite_table, in_skb, nlh, req);
 164 }
 165
 166 static const struct inet_diag_handler udplite_diag_handler = {
 167         .dump            = udplite_diag_dump,
 168         .dump_one        = udplite_diag_dump_one,
 169         .idiag_type      = IPPROTO_UDPLITE,
 170 };
 171
 172 static int __init udp_diag_init(void)
 173 {
 174         int err;
 175
 176         err = inet_diag_register(&udp_diag_handler);
 177         if (err)
 178                 goto out;
 179         err = inet_diag_register(&udplite_diag_handler);
 180         if (err)
 181                 goto out_lite;
 182 out:
 183         return err;
 184 out_lite:
 185         inet_diag_unregister(&udp_diag_handler);
 186         goto out;
 187 }
 188
 189 static void __exit udp_diag_exit(void)
 190 {
 191         inet_diag_unregister(&udplite_diag_handler);
 192         inet_diag_unregister(&udp_diag_handler);
 193 }
 194
 195 module_init(udp_diag_init);
 196 module_exit(udp_diag_exit);
 197 MODULE_LICENSE("GPL");
 198 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 17);
 199 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 136);