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/sock_diag.h>
  19
  20 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
  21                 struct netlink_callback *cb, struct inet_diag_req_v2 *req,
  22                 struct nlattr *bc)
  23 {
  24         if (!inet_diag_bc_sk(bc, sk))
  25                 return 0;
  26
  27         return inet_sk_diag_fill(sk, NULL, skb, req,
  28                         sk_user_ns(NETLINK_CB(cb->skb).sk),
  29                         NETLINK_CB(cb->skb).portid,
  30                         cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
  31 }
  32
  33 static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
  34                 const struct nlmsghdr *nlh, struct inet_diag_req_v2 *req)
  35 {
  36         int err = -EINVAL;
  37         struct sock *sk;
  38         struct sk_buff *rep;
  39         struct net *net = sock_net(in_skb->sk);
  40
  41         if (req->sdiag_family == AF_INET)
  42                 sk = __udp4_lib_lookup(net,
  43                                 req->id.idiag_src[0], req->id.idiag_sport,
  44                                 req->id.idiag_dst[0], req->id.idiag_dport,
  45                                 req->id.idiag_if, tbl);
  46 #if IS_ENABLED(CONFIG_IPV6)
  47         else if (req->sdiag_family == AF_INET6)
  48                 sk = __udp6_lib_lookup(net,
  49                                 (struct in6_addr *)req->id.idiag_src,
  50                                 req->id.idiag_sport,
  51                                 (struct in6_addr *)req->id.idiag_dst,
  52                                 req->id.idiag_dport,
  53                                 req->id.idiag_if, tbl);
  54 #endif
  55         else
  56                 goto out_nosk;
  57
  58         err = -ENOENT;
  59         if (sk == NULL)
  60                 goto out_nosk;
  61
  62         err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
  63         if (err)
  64                 goto out;
  65
  66         err = -ENOMEM;
  67         rep = nlmsg_new(sizeof(struct inet_diag_msg) +
  68                         sizeof(struct inet_diag_meminfo) + 64,
  69                         GFP_KERNEL);
  70         if (!rep)
  71                 goto out;
  72
  73         err = inet_sk_diag_fill(sk, NULL, rep, req,
  74                            sk_user_ns(NETLINK_CB(in_skb).sk),
  75                            NETLINK_CB(in_skb).portid,
  76                            nlh->nlmsg_seq, 0, nlh);
  77         if (err < 0) {
  78                 WARN_ON(err == -EMSGSIZE);
  79                 kfree_skb(rep);
  80                 goto out;
  81         }
  82         err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
  83                               MSG_DONTWAIT);
  84         if (err > 0)
  85                 err = 0;
  86 out:
  87         if (sk)
  88                 sock_put(sk);
  89 out_nosk:
  90         return err;
  91 }
  92
  93 static void udp_dump(struct udp_table *table, struct sk_buff *skb, struct netlink_callback *cb,
  94                 struct inet_diag_req_v2 *r, struct nlattr *bc)
  95 {
  96         int num, s_num, slot, s_slot;
  97         struct net *net = sock_net(skb->sk);
  98
  99         s_slot = cb->args[0];
 100         num = s_num = cb->args[1];
 101
 102         for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) {
 103                 struct sock *sk;
 104                 struct hlist_nulls_node *node;
 105                 struct udp_hslot *hslot = &table->hash[slot];
 106
 107                 num = 0;
 108
 109                 if (hlist_nulls_empty(&hslot->head))
 110                         continue;
 111
 112                 spin_lock_bh(&hslot->lock);
 113                 sk_nulls_for_each(sk, node, &hslot->head) {
 114                         struct inet_sock *inet = inet_sk(sk);
 115
 116                         if (!net_eq(sock_net(sk), net))
 117                                 continue;
 118                         if (num < s_num)
 119                                 goto next;
 120                         if (!(r->idiag_states & (1 << sk->sk_state)))
 121                                 goto next;
 122                         if (r->sdiag_family != AF_UNSPEC &&
 123                                         sk->sk_family != r->sdiag_family)
 124                                 goto next;
 125                         if (r->id.idiag_sport != inet->inet_sport &&
 126                             r->id.idiag_sport)
 127                                 goto next;
 128                         if (r->id.idiag_dport != inet->inet_dport &&
 129                             r->id.idiag_dport)
 130                                 goto next;
 131
 132                         if (sk_diag_dump(sk, skb, cb, r, bc) < 0) {
 133                                 spin_unlock_bh(&hslot->lock);
 134                                 goto done;
 135                         }
 136 next:
 137                         num++;
 138                 }
 139                 spin_unlock_bh(&hslot->lock);
 140         }
 141 done:
 142         cb->args[0] = slot;
 143         cb->args[1] = num;
 144 }
 145
 146 static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 147                 struct inet_diag_req_v2 *r, struct nlattr *bc)
 148 {
 149         udp_dump(&udp_table, skb, cb, r, bc);
 150 }
 151
 152 static int udp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
 153                 struct inet_diag_req_v2 *req)
 154 {
 155         return udp_dump_one(&udp_table, in_skb, nlh, req);
 156 }
 157
 158 static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
 159                 void *info)
 160 {
 161         r->idiag_rqueue = sk_rmem_alloc_get(sk);
 162         r->idiag_wqueue = sk_wmem_alloc_get(sk);
 163 }
 164
 165 static const struct inet_diag_handler udp_diag_handler = {
 166         .dump            = udp_diag_dump,
 167         .dump_one        = udp_diag_dump_one,
 168         .idiag_get_info  = udp_diag_get_info,
 169         .idiag_type      = IPPROTO_UDP,
 170 };
 171
 172 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 173                 struct inet_diag_req_v2 *r, struct nlattr *bc)
 174 {
 175         udp_dump(&udplite_table, skb, cb, r, bc);
 176 }
 177
 178 static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
 179                 struct inet_diag_req_v2 *req)
 180 {
 181         return udp_dump_one(&udplite_table, in_skb, nlh, req);
 182 }
 183
 184 static const struct inet_diag_handler udplite_diag_handler = {
 185         .dump            = udplite_diag_dump,
 186         .dump_one        = udplite_diag_dump_one,
 187         .idiag_get_info  = udp_diag_get_info,
 188         .idiag_type      = IPPROTO_UDPLITE,
 189 };
 190
 191 static int __init udp_diag_init(void)
 192 {
 193         int err;
 194
 195         err = inet_diag_register(&udp_diag_handler);
 196         if (err)
 197                 goto out;
 198         err = inet_diag_register(&udplite_diag_handler);
 199         if (err)
 200                 goto out_lite;
 201 out:
 202         return err;
 203 out_lite:
 204         inet_diag_unregister(&udp_diag_handler);
 205         goto out;
 206 }
 207
 208 static void __exit udp_diag_exit(void)
 209 {
 210         inet_diag_unregister(&udplite_diag_handler);
 211         inet_diag_unregister(&udp_diag_handler);
 212 }
 213
 214 module_init(udp_diag_init);
 215 module_exit(udp_diag_exit);
 216 MODULE_LICENSE("GPL");
 217 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */);
 218 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */);