linux/net/ipv4/udp_diag.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * udp_diag.c   Module for monitoring UDP transport protocols sockets.
   4 *
   5 * Authors:     Pavel Emelyanov, <xemul@parallels.com>
   6 */
   7
   8
   9#include <linux/module.h>
  10#include <linux/inet_diag.h>
  11#include <linux/udp.h>
  12#include <net/udp.h>
  13#include <net/udplite.h>
  14#include <linux/sock_diag.h>
  15
  16static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
  17                        struct netlink_callback *cb,
  18                        const struct inet_diag_req_v2 *req,
  19                        struct nlattr *bc, bool net_admin)
  20{
  21        if (!inet_diag_bc_sk(bc, sk))
  22                return 0;
  23
  24        return inet_sk_diag_fill(sk, NULL, skb, cb, req, NLM_F_MULTI,
  25                                 net_admin);
  26}
  27
  28static int udp_dump_one(struct udp_table *tbl,
  29                        struct netlink_callback *cb,
  30                        const struct inet_diag_req_v2 *req)
  31{
  32        struct sk_buff *in_skb = cb->skb;
  33        int err;
  34        struct sock *sk = NULL;
  35        struct sk_buff *rep;
  36        struct net *net = sock_net(in_skb->sk);
  37
  38        rcu_read_lock();
  39        if (req->sdiag_family == AF_INET)
  40                /* src and dst are swapped for historical reasons */
  41                sk = __udp4_lib_lookup(net,
  42                                req->id.idiag_src[0], req->id.idiag_sport,
  43                                req->id.idiag_dst[0], req->id.idiag_dport,
  44                                req->id.idiag_if, 0, tbl, NULL);
  45#if IS_ENABLED(CONFIG_IPV6)
  46        else if (req->sdiag_family == AF_INET6)
  47                sk = __udp6_lib_lookup(net,
  48                                (struct in6_addr *)req->id.idiag_src,
  49                                req->id.idiag_sport,
  50                                (struct in6_addr *)req->id.idiag_dst,
  51                                req->id.idiag_dport,
  52                                req->id.idiag_if, 0, tbl, NULL);
  53#endif
  54        if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
  55                sk = NULL;
  56        rcu_read_unlock();
  57        err = -ENOENT;
  58        if (!sk)
  59                goto out_nosk;
  60
  61        err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
  62        if (err)
  63                goto out;
  64
  65        err = -ENOMEM;
  66        rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) +
  67                        inet_diag_msg_attrs_size() +
  68                        nla_total_size(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, cb, req, 0,
  74                                netlink_net_capable(in_skb, CAP_NET_ADMIN));
  75        if (err < 0) {
  76                WARN_ON(err == -EMSGSIZE);
  77                kfree_skb(rep);
  78                goto out;
  79        }
  80        err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid);
  81
  82out:
  83        if (sk)
  84                sock_put(sk);
  85out_nosk:
  86        return err;
  87}
  88
  89static void udp_dump(struct udp_table *table, struct sk_buff *skb,
  90                     struct netlink_callback *cb,
  91                     const struct inet_diag_req_v2 *r)
  92{
  93        bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
  94        struct net *net = sock_net(skb->sk);
  95        struct inet_diag_dump_data *cb_data;
  96        int num, s_num, slot, s_slot;
  97        struct nlattr *bc;
  98
  99        cb_data = cb->data;
 100        bc = cb_data->inet_diag_nla_bc;
 101        s_slot = cb->args[0];
 102        num = s_num = cb->args[1];
 103
 104        for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) {
 105                struct udp_hslot *hslot = &table->hash[slot];
 106                struct sock *sk;
 107
 108                num = 0;
 109
 110                if (hlist_empty(&hslot->head))
 111                        continue;
 112
 113                spin_lock_bh(&hslot->lock);
 114                sk_for_each(sk, &hslot->head) {
 115                        struct inet_sock *inet = inet_sk(sk);
 116
 117                        if (!net_eq(sock_net(sk), net))
 118                                continue;
 119                        if (num < s_num)
 120                                goto next;
 121                        if (!(r->idiag_states & (1 << sk->sk_state)))
 122                                goto next;
 123                        if (r->sdiag_family != AF_UNSPEC &&
 124                                        sk->sk_family != r->sdiag_family)
 125                                goto next;
 126                        if (r->id.idiag_sport != inet->inet_sport &&
 127                            r->id.idiag_sport)
 128                                goto next;
 129                        if (r->id.idiag_dport != inet->inet_dport &&
 130                            r->id.idiag_dport)
 131                                goto next;
 132
 133                        if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) {
 134                                spin_unlock_bh(&hslot->lock);
 135                                goto done;
 136                        }
 137next:
 138                        num++;
 139                }
 140                spin_unlock_bh(&hslot->lock);
 141        }
 142done:
 143        cb->args[0] = slot;
 144        cb->args[1] = num;
 145}
 146
 147static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 148                          const struct inet_diag_req_v2 *r)
 149{
 150        udp_dump(&udp_table, skb, cb, r);
 151}
 152
 153static int udp_diag_dump_one(struct netlink_callback *cb,
 154                             const struct inet_diag_req_v2 *req)
 155{
 156        return udp_dump_one(&udp_table, cb, req);
 157}
 158
 159static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
 160                void *info)
 161{
 162        r->idiag_rqueue = udp_rqueue_get(sk);
 163        r->idiag_wqueue = sk_wmem_alloc_get(sk);
 164}
 165
 166#ifdef CONFIG_INET_DIAG_DESTROY
 167static int __udp_diag_destroy(struct sk_buff *in_skb,
 168                              const struct inet_diag_req_v2 *req,
 169                              struct udp_table *tbl)
 170{
 171        struct net *net = sock_net(in_skb->sk);
 172        struct sock *sk;
 173        int err;
 174
 175        rcu_read_lock();
 176
 177        if (req->sdiag_family == AF_INET)
 178                sk = __udp4_lib_lookup(net,
 179                                req->id.idiag_dst[0], req->id.idiag_dport,
 180                                req->id.idiag_src[0], req->id.idiag_sport,
 181                                req->id.idiag_if, 0, tbl, NULL);
 182#if IS_ENABLED(CONFIG_IPV6)
 183        else if (req->sdiag_family == AF_INET6) {
 184                if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
 185                    ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
 186                        sk = __udp4_lib_lookup(net,
 187                                        req->id.idiag_dst[3], req->id.idiag_dport,
 188                                        req->id.idiag_src[3], req->id.idiag_sport,
 189                                        req->id.idiag_if, 0, tbl, NULL);
 190
 191                else
 192                        sk = __udp6_lib_lookup(net,
 193                                        (struct in6_addr *)req->id.idiag_dst,
 194                                        req->id.idiag_dport,
 195                                        (struct in6_addr *)req->id.idiag_src,
 196                                        req->id.idiag_sport,
 197                                        req->id.idiag_if, 0, tbl, NULL);
 198        }
 199#endif
 200        else {
 201                rcu_read_unlock();
 202                return -EINVAL;
 203        }
 204
 205        if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
 206                sk = NULL;
 207
 208        rcu_read_unlock();
 209
 210        if (!sk)
 211                return -ENOENT;
 212
 213        if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) {
 214                sock_put(sk);
 215                return -ENOENT;
 216        }
 217
 218        err = sock_diag_destroy(sk, ECONNABORTED);
 219
 220        sock_put(sk);
 221
 222        return err;
 223}
 224
 225static int udp_diag_destroy(struct sk_buff *in_skb,
 226                            const struct inet_diag_req_v2 *req)
 227{
 228        return __udp_diag_destroy(in_skb, req, &udp_table);
 229}
 230
 231static int udplite_diag_destroy(struct sk_buff *in_skb,
 232                                const struct inet_diag_req_v2 *req)
 233{
 234        return __udp_diag_destroy(in_skb, req, &udplite_table);
 235}
 236
 237#endif
 238
 239static const struct inet_diag_handler udp_diag_handler = {
 240        .dump            = udp_diag_dump,
 241        .dump_one        = udp_diag_dump_one,
 242        .idiag_get_info  = udp_diag_get_info,
 243        .idiag_type      = IPPROTO_UDP,
 244        .idiag_info_size = 0,
 245#ifdef CONFIG_INET_DIAG_DESTROY
 246        .destroy         = udp_diag_destroy,
 247#endif
 248};
 249
 250static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 251                              const struct inet_diag_req_v2 *r)
 252{
 253        udp_dump(&udplite_table, skb, cb, r);
 254}
 255
 256static int udplite_diag_dump_one(struct netlink_callback *cb,
 257                                 const struct inet_diag_req_v2 *req)
 258{
 259        return udp_dump_one(&udplite_table, cb, req);
 260}
 261
 262static const struct inet_diag_handler udplite_diag_handler = {
 263        .dump            = udplite_diag_dump,
 264        .dump_one        = udplite_diag_dump_one,
 265        .idiag_get_info  = udp_diag_get_info,
 266        .idiag_type      = IPPROTO_UDPLITE,
 267        .idiag_info_size = 0,
 268#ifdef CONFIG_INET_DIAG_DESTROY
 269        .destroy         = udplite_diag_destroy,
 270#endif
 271};
 272
 273static int __init udp_diag_init(void)
 274{
 275        int err;
 276
 277        err = inet_diag_register(&udp_diag_handler);
 278        if (err)
 279                goto out;
 280        err = inet_diag_register(&udplite_diag_handler);
 281        if (err)
 282                goto out_lite;
 283out:
 284        return err;
 285out_lite:
 286        inet_diag_unregister(&udp_diag_handler);
 287        goto out;
 288}
 289
 290static void __exit udp_diag_exit(void)
 291{
 292        inet_diag_unregister(&udplite_diag_handler);
 293        inet_diag_unregister(&udp_diag_handler);
 294}
 295
 296module_init(udp_diag_init);
 297module_exit(udp_diag_exit);
 298MODULE_LICENSE("GPL");
 299MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */);
 300MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */);
 301