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,
  22                         const struct inet_diag_req_v2 *req,
  23                         struct nlattr *bc, bool net_admin)
  24 {
  25         if (!inet_diag_bc_sk(bc, sk))
  26                 return 0;
  27
  28         return inet_sk_diag_fill(sk, NULL, skb, req,
  29                         sk_user_ns(NETLINK_CB(cb->skb).sk),
  30                         NETLINK_CB(cb->skb).portid,
  31                         cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh, net_admin);
  32 }
  33
  34 static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
  35                         const struct nlmsghdr *nlh,
  36                         const struct inet_diag_req_v2 *req)
  37 {
  38         int err = -EINVAL;
  39         struct sock *sk = NULL;
  40         struct sk_buff *rep;
  41         struct net *net = sock_net(in_skb->sk);
  42
  43         rcu_read_lock();
  44         if (req->sdiag_family == AF_INET)
  45                 sk = __udp4_lib_lookup(net,
  46                                 req->id.idiag_src[0], req->id.idiag_sport,
  47                                 req->id.idiag_dst[0], req->id.idiag_dport,
  48                                 req->id.idiag_if, 0, tbl, NULL);
  49 #if IS_ENABLED(CONFIG_IPV6)
  50         else if (req->sdiag_family == AF_INET6)
  51                 sk = __udp6_lib_lookup(net,
  52                                 (struct in6_addr *)req->id.idiag_src,
  53                                 req->id.idiag_sport,
  54                                 (struct in6_addr *)req->id.idiag_dst,
  55                                 req->id.idiag_dport,
  56                                 req->id.idiag_if, 0, tbl, NULL);
  57 #endif
  58         if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
  59                 sk = NULL;
  60         rcu_read_unlock();
  61         err = -ENOENT;
  62         if (!sk)
  63                 goto out_nosk;
  64
  65         err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
  66         if (err)
  67                 goto out;
  68
  69         err = -ENOMEM;
  70         rep = nlmsg_new(sizeof(struct inet_diag_msg) +
  71                         sizeof(struct inet_diag_meminfo) + 64,
  72                         GFP_KERNEL);
  73         if (!rep)
  74                 goto out;
  75
  76         err = inet_sk_diag_fill(sk, NULL, rep, req,
  77                            sk_user_ns(NETLINK_CB(in_skb).sk),
  78                            NETLINK_CB(in_skb).portid,
  79                            nlh->nlmsg_seq, 0, nlh,
  80                            netlink_net_capable(in_skb, CAP_NET_ADMIN));
  81         if (err < 0) {
  82                 WARN_ON(err == -EMSGSIZE);
  83                 kfree_skb(rep);
  84                 goto out;
  85         }
  86         err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
  87                               MSG_DONTWAIT);
  88         if (err > 0)
  89                 err = 0;
  90 out:
  91         if (sk)
  92                 sock_put(sk);
  93 out_nosk:
  94         return err;
  95 }
  96
  97 static void udp_dump(struct udp_table *table, struct sk_buff *skb,
  98                      struct netlink_callback *cb,
  99                      const struct inet_diag_req_v2 *r, struct nlattr *bc)
 100 {
 101         bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
 102         struct net *net = sock_net(skb->sk);
 103         int num, s_num, slot, s_slot;
 104
 105         s_slot = cb->args[0];
 106         num = s_num = cb->args[1];
 107
 108         for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) {
 109                 struct udp_hslot *hslot = &table->hash[slot];
 110                 struct sock *sk;
 111
 112                 num = 0;
 113
 114                 if (hlist_empty(&hslot->head))
 115                         continue;
 116
 117                 spin_lock_bh(&hslot->lock);
 118                 sk_for_each(sk, &hslot->head) {
 119                         struct inet_sock *inet = inet_sk(sk);
 120
 121                         if (!net_eq(sock_net(sk), net))
 122                                 continue;
 123                         if (num < s_num)
 124                                 goto next;
 125                         if (!(r->idiag_states & (1 << sk->sk_state)))
 126                                 goto next;
 127                         if (r->sdiag_family != AF_UNSPEC &&
 128                                         sk->sk_family != r->sdiag_family)
 129                                 goto next;
 130                         if (r->id.idiag_sport != inet->inet_sport &&
 131                             r->id.idiag_sport)
 132                                 goto next;
 133                         if (r->id.idiag_dport != inet->inet_dport &&
 134                             r->id.idiag_dport)
 135                                 goto next;
 136
 137                         if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) {
 138                                 spin_unlock_bh(&hslot->lock);
 139                                 goto done;
 140                         }
 141 next:
 142                         num++;
 143                 }
 144                 spin_unlock_bh(&hslot->lock);
 145         }
 146 done:
 147         cb->args[0] = slot;
 148         cb->args[1] = num;
 149 }
 150
 151 static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 152                           const struct inet_diag_req_v2 *r, struct nlattr *bc)
 153 {
 154         udp_dump(&udp_table, skb, cb, r, bc);
 155 }
 156
 157 static int udp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
 158                              const struct inet_diag_req_v2 *req)
 159 {
 160         return udp_dump_one(&udp_table, in_skb, nlh, req);
 161 }
 162
 163 static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
 164                 void *info)
 165 {
 166         r->idiag_rqueue = sk_rmem_alloc_get(sk);
 167         r->idiag_wqueue = sk_wmem_alloc_get(sk);
 168 }
 169
 170 #ifdef CONFIG_INET_DIAG_DESTROY
 171 static int __udp_diag_destroy(struct sk_buff *in_skb,
 172                               const struct inet_diag_req_v2 *req,
 173                               struct udp_table *tbl)
 174 {
 175         struct net *net = sock_net(in_skb->sk);
 176         struct sock *sk;
 177         int err;
 178
 179         rcu_read_lock();
 180
 181         if (req->sdiag_family == AF_INET)
 182                 sk = __udp4_lib_lookup(net,
 183                                 req->id.idiag_dst[0], req->id.idiag_dport,
 184                                 req->id.idiag_src[0], req->id.idiag_sport,
 185                                 req->id.idiag_if, 0, tbl, NULL);
 186 #if IS_ENABLED(CONFIG_IPV6)
 187         else if (req->sdiag_family == AF_INET6) {
 188                 if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
 189                     ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
 190                         sk = __udp4_lib_lookup(net,
 191                                         req->id.idiag_dst[3], req->id.idiag_dport,
 192                                         req->id.idiag_src[3], req->id.idiag_sport,
 193                                         req->id.idiag_if, 0, tbl, NULL);
 194
 195                 else
 196                         sk = __udp6_lib_lookup(net,
 197                                         (struct in6_addr *)req->id.idiag_dst,
 198                                         req->id.idiag_dport,
 199                                         (struct in6_addr *)req->id.idiag_src,
 200                                         req->id.idiag_sport,
 201                                         req->id.idiag_if, 0, tbl, NULL);
 202         }
 203 #endif
 204         else {
 205                 rcu_read_unlock();
 206                 return -EINVAL;
 207         }
 208
 209         if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
 210                 sk = NULL;
 211
 212         rcu_read_unlock();
 213
 214         if (!sk)
 215                 return -ENOENT;
 216
 217         if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) {
 218                 sock_put(sk);
 219                 return -ENOENT;
 220         }
 221
 222         err = sock_diag_destroy(sk, ECONNABORTED);
 223
 224         sock_put(sk);
 225
 226         return err;
 227 }
 228
 229 static int udp_diag_destroy(struct sk_buff *in_skb,
 230                             const struct inet_diag_req_v2 *req)
 231 {
 232         return __udp_diag_destroy(in_skb, req, &udp_table);
 233 }
 234
 235 static int udplite_diag_destroy(struct sk_buff *in_skb,
 236                                 const struct inet_diag_req_v2 *req)
 237 {
 238         return __udp_diag_destroy(in_skb, req, &udplite_table);
 239 }
 240
 241 #endif
 242
 243 static const struct inet_diag_handler udp_diag_handler = {
 244         .dump            = udp_diag_dump,
 245         .dump_one        = udp_diag_dump_one,
 246         .idiag_get_info  = udp_diag_get_info,
 247         .idiag_type      = IPPROTO_UDP,
 248         .idiag_info_size = 0,
 249 #ifdef CONFIG_INET_DIAG_DESTROY
 250         .destroy         = udp_diag_destroy,
 251 #endif
 252 };
 253
 254 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 255                               const struct inet_diag_req_v2 *r,
 256                               struct nlattr *bc)
 257 {
 258         udp_dump(&udplite_table, skb, cb, r, bc);
 259 }
 260
 261 static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
 262                                  const struct inet_diag_req_v2 *req)
 263 {
 264         return udp_dump_one(&udplite_table, in_skb, nlh, req);
 265 }
 266
 267 static const struct inet_diag_handler udplite_diag_handler = {
 268         .dump            = udplite_diag_dump,
 269         .dump_one        = udplite_diag_dump_one,
 270         .idiag_get_info  = udp_diag_get_info,
 271         .idiag_type      = IPPROTO_UDPLITE,
 272         .idiag_info_size = 0,
 273 #ifdef CONFIG_INET_DIAG_DESTROY
 274         .destroy         = udplite_diag_destroy,
 275 #endif
 276 };
 277
 278 static int __init udp_diag_init(void)
 279 {
 280         int err;
 281
 282         err = inet_diag_register(&udp_diag_handler);
 283         if (err)
 284                 goto out;
 285         err = inet_diag_register(&udplite_diag_handler);
 286         if (err)
 287                 goto out_lite;
 288 out:
 289         return err;
 290 out_lite:
 291         inet_diag_unregister(&udp_diag_handler);
 292         goto out;
 293 }
 294
 295 static void __exit udp_diag_exit(void)
 296 {
 297         inet_diag_unregister(&udplite_diag_handler);
 298         inet_diag_unregister(&udp_diag_handler);
 299 }
 300
 301 module_init(udp_diag_init);
 302 module_exit(udp_diag_exit);
 303 MODULE_LICENSE("GPL");
 304 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */);
 305 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */);