net/ipv4/raw_diag.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 #include <linux/module.h>
   3
   4 #include <linux/inet_diag.h>
   5 #include <linux/sock_diag.h>
   6
   7 #include <net/inet_sock.h>
   8 #include <net/raw.h>
   9 #include <net/rawv6.h>
  10
  11 #ifdef pr_fmt
  12 # undef pr_fmt
  13 #endif
  14
  15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  16
  17 static struct raw_hashinfo *
  18 raw_get_hashinfo(const struct inet_diag_req_v2 *r)
  19 {
  20         if (r->sdiag_family == AF_INET) {
  21                 return &raw_v4_hashinfo;
  22 #if IS_ENABLED(CONFIG_IPV6)
  23         } else if (r->sdiag_family == AF_INET6) {
  24                 return &raw_v6_hashinfo;
  25 #endif
  26         } else {
  27                 return ERR_PTR(-EINVAL);
  28         }
  29 }
  30
  31 /*
  32  * Due to requirement of not breaking user API we can't simply
  33  * rename @pad field in inet_diag_req_v2 structure, instead
  34  * use helper to figure it out.
  35  */
  36
  37 static bool raw_lookup(struct net *net, struct sock *sk,
  38                        const struct inet_diag_req_v2 *req)
  39 {
  40         struct inet_diag_req_raw *r = (void *)req;
  41
  42         if (r->sdiag_family == AF_INET)
  43                 return raw_v4_match(net, sk, r->sdiag_raw_protocol,
  44                                     r->id.idiag_dst[0],
  45                                     r->id.idiag_src[0],
  46                                     r->id.idiag_if, 0);
  47 #if IS_ENABLED(CONFIG_IPV6)
  48         else
  49                 return raw_v6_match(net, sk, r->sdiag_raw_protocol,
  50                                     (const struct in6_addr *)r->id.idiag_src,
  51                                     (const struct in6_addr *)r->id.idiag_dst,
  52                                     r->id.idiag_if, 0);
  53 #endif
  54         return false;
  55 }
  56
  57 static struct sock *raw_sock_get(struct net *net, const struct inet_diag_req_v2 *r)
  58 {
  59         struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
  60         struct hlist_nulls_head *hlist;
  61         struct hlist_nulls_node *hnode;
  62         struct sock *sk;
  63         int slot;
  64
  65         if (IS_ERR(hashinfo))
  66                 return ERR_CAST(hashinfo);
  67
  68         rcu_read_lock();
  69         for (slot = 0; slot < RAW_HTABLE_SIZE; slot++) {
  70                 hlist = &hashinfo->ht[slot];
  71                 sk_nulls_for_each(sk, hnode, hlist) {
  72                         if (raw_lookup(net, sk, r)) {
  73                                 /*
  74                                  * Grab it and keep until we fill
  75                                  * diag message to be reported, so
  76                                  * caller should call sock_put then.
  77                                  */
  78                                 if (refcount_inc_not_zero(&sk->sk_refcnt))
  79                                         goto out_unlock;
  80                         }
  81                 }
  82         }
  83         sk = ERR_PTR(-ENOENT);
  84 out_unlock:
  85         rcu_read_unlock();
  86
  87         return sk;
  88 }
  89
  90 static int raw_diag_dump_one(struct netlink_callback *cb,
  91                              const struct inet_diag_req_v2 *r)
  92 {
  93         struct sk_buff *in_skb = cb->skb;
  94         struct sk_buff *rep;
  95         struct sock *sk;
  96         struct net *net;
  97         int err;
  98
  99         net = sock_net(in_skb->sk);
 100         sk = raw_sock_get(net, r);
 101         if (IS_ERR(sk))
 102                 return PTR_ERR(sk);
 103
 104         rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) +
 105                         inet_diag_msg_attrs_size() +
 106                         nla_total_size(sizeof(struct inet_diag_meminfo)) + 64,
 107                         GFP_KERNEL);
 108         if (!rep) {
 109                 sock_put(sk);
 110                 return -ENOMEM;
 111         }
 112
 113         err = inet_sk_diag_fill(sk, NULL, rep, cb, r, 0,
 114                                 netlink_net_capable(in_skb, CAP_NET_ADMIN));
 115         sock_put(sk);
 116
 117         if (err < 0) {
 118                 kfree_skb(rep);
 119                 return err;
 120         }
 121
 122         err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid);
 123
 124         return err;
 125 }
 126
 127 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
 128                         struct netlink_callback *cb,
 129                         const struct inet_diag_req_v2 *r,
 130                         struct nlattr *bc, bool net_admin)
 131 {
 132         if (!inet_diag_bc_sk(bc, sk))
 133                 return 0;
 134
 135         return inet_sk_diag_fill(sk, NULL, skb, cb, r, NLM_F_MULTI, net_admin);
 136 }
 137
 138 static void raw_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 139                           const struct inet_diag_req_v2 *r)
 140 {
 141         bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
 142         struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
 143         struct net *net = sock_net(skb->sk);
 144         struct inet_diag_dump_data *cb_data;
 145         struct hlist_nulls_head *hlist;
 146         struct hlist_nulls_node *hnode;
 147         int num, s_num, slot, s_slot;
 148         struct sock *sk = NULL;
 149         struct nlattr *bc;
 150
 151         if (IS_ERR(hashinfo))
 152                 return;
 153
 154         cb_data = cb->data;
 155         bc = cb_data->inet_diag_nla_bc;
 156         s_slot = cb->args[0];
 157         num = s_num = cb->args[1];
 158
 159         rcu_read_lock();
 160         for (slot = s_slot; slot < RAW_HTABLE_SIZE; s_num = 0, slot++) {
 161                 num = 0;
 162
 163                 hlist = &hashinfo->ht[slot];
 164                 sk_nulls_for_each(sk, hnode, hlist) {
 165                         struct inet_sock *inet = inet_sk(sk);
 166
 167                         if (!net_eq(sock_net(sk), net))
 168                                 continue;
 169                         if (num < s_num)
 170                                 goto next;
 171                         if (sk->sk_family != r->sdiag_family)
 172                                 goto next;
 173                         if (r->id.idiag_sport != inet->inet_sport &&
 174                             r->id.idiag_sport)
 175                                 goto next;
 176                         if (r->id.idiag_dport != inet->inet_dport &&
 177                             r->id.idiag_dport)
 178                                 goto next;
 179                         if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0)
 180                                 goto out_unlock;
 181 next:
 182                         num++;
 183                 }
 184         }
 185
 186 out_unlock:
 187         rcu_read_unlock();
 188
 189         cb->args[0] = slot;
 190         cb->args[1] = num;
 191 }
 192
 193 static void raw_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
 194                               void *info)
 195 {
 196         r->idiag_rqueue = sk_rmem_alloc_get(sk);
 197         r->idiag_wqueue = sk_wmem_alloc_get(sk);
 198 }
 199
 200 #ifdef CONFIG_INET_DIAG_DESTROY
 201 static int raw_diag_destroy(struct sk_buff *in_skb,
 202                             const struct inet_diag_req_v2 *r)
 203 {
 204         struct net *net = sock_net(in_skb->sk);
 205         struct sock *sk;
 206         int err;
 207
 208         sk = raw_sock_get(net, r);
 209         if (IS_ERR(sk))
 210                 return PTR_ERR(sk);
 211         err = sock_diag_destroy(sk, ECONNABORTED);
 212         sock_put(sk);
 213         return err;
 214 }
 215 #endif
 216
 217 static const struct inet_diag_handler raw_diag_handler = {
 218         .dump                   = raw_diag_dump,
 219         .dump_one               = raw_diag_dump_one,
 220         .idiag_get_info         = raw_diag_get_info,
 221         .idiag_type             = IPPROTO_RAW,
 222         .idiag_info_size        = 0,
 223 #ifdef CONFIG_INET_DIAG_DESTROY
 224         .destroy                = raw_diag_destroy,
 225 #endif
 226 };
 227
 228 static void __always_unused __check_inet_diag_req_raw(void)
 229 {
 230         /*
 231          * Make sure the two structures are identical,
 232          * except the @pad field.
 233          */
 234 #define __offset_mismatch(m1, m2)                       \
 235         (offsetof(struct inet_diag_req_v2, m1) !=       \
 236          offsetof(struct inet_diag_req_raw, m2))
 237
 238         BUILD_BUG_ON(sizeof(struct inet_diag_req_v2) !=
 239                      sizeof(struct inet_diag_req_raw));
 240         BUILD_BUG_ON(__offset_mismatch(sdiag_family, sdiag_family));
 241         BUILD_BUG_ON(__offset_mismatch(sdiag_protocol, sdiag_protocol));
 242         BUILD_BUG_ON(__offset_mismatch(idiag_ext, idiag_ext));
 243         BUILD_BUG_ON(__offset_mismatch(pad, sdiag_raw_protocol));
 244         BUILD_BUG_ON(__offset_mismatch(idiag_states, idiag_states));
 245         BUILD_BUG_ON(__offset_mismatch(id, id));
 246 #undef __offset_mismatch
 247 }
 248
 249 static int __init raw_diag_init(void)
 250 {
 251         return inet_diag_register(&raw_diag_handler);
 252 }
 253
 254 static void __exit raw_diag_exit(void)
 255 {
 256         inet_diag_unregister(&raw_diag_handler);
 257 }
 258
 259 module_init(raw_diag_init);
 260 module_exit(raw_diag_exit);
 261 MODULE_LICENSE("GPL");
 262 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-255 /* AF_INET - IPPROTO_RAW */);
 263 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10-255 /* AF_INET6 - IPPROTO_RAW */);