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 struct sock *raw_lookup(struct net *net, struct sock *from,
  38                                const struct inet_diag_req_v2 *req)
  39 {
  40         struct inet_diag_req_raw *r = (void *)req;
  41         struct sock *sk = NULL;
  42
  43         if (r->sdiag_family == AF_INET)
  44                 sk = __raw_v4_lookup(net, from, r->sdiag_raw_protocol,
  45                                      r->id.idiag_dst[0],
  46                                      r->id.idiag_src[0],
  47                                      r->id.idiag_if, 0);
  48 #if IS_ENABLED(CONFIG_IPV6)
  49         else
  50                 sk = __raw_v6_lookup(net, from, r->sdiag_raw_protocol,
  51                                      (const struct in6_addr *)r->id.idiag_src,
  52                                      (const struct in6_addr *)r->id.idiag_dst,
  53                                      r->id.idiag_if, 0);
  54 #endif
  55         return sk;
  56 }
  57
  58 static struct sock *raw_sock_get(struct net *net, const struct inet_diag_req_v2 *r)
  59 {
  60         struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
  61         struct sock *sk = NULL, *s;
  62         int slot;
  63
  64         if (IS_ERR(hashinfo))
  65                 return ERR_CAST(hashinfo);
  66
  67         read_lock(&hashinfo->lock);
  68         for (slot = 0; slot < RAW_HTABLE_SIZE; slot++) {
  69                 sk_for_each(s, &hashinfo->ht[slot]) {
  70                         sk = raw_lookup(net, s, r);
  71                         if (sk) {
  72                                 /*
  73                                  * Grab it and keep until we fill
  74                                  * diag meaage to be reported, so
  75                                  * caller should call sock_put then.
  76                                  * We can do that because we're keeping
  77                                  * hashinfo->lock here.
  78                                  */
  79                                 sock_hold(sk);
  80                                 goto out_unlock;
  81                         }
  82                 }
  83         }
  84 out_unlock:
  85         read_unlock(&hashinfo->lock);
  86
  87         return sk ? sk : ERR_PTR(-ENOENT);
  88 }
  89
  90 static int raw_diag_dump_one(struct sk_buff *in_skb,
  91                              const struct nlmsghdr *nlh,
  92                              const struct inet_diag_req_v2 *r)
  93 {
  94         struct net *net = sock_net(in_skb->sk);
  95         struct sk_buff *rep;
  96         struct sock *sk;
  97         int err;
  98
  99         sk = raw_sock_get(net, r);
 100         if (IS_ERR(sk))
 101                 return PTR_ERR(sk);
 102
 103         rep = nlmsg_new(sizeof(struct inet_diag_msg) +
 104                         sizeof(struct inet_diag_meminfo) + 64,
 105                         GFP_KERNEL);
 106         if (!rep) {
 107                 sock_put(sk);
 108                 return -ENOMEM;
 109         }
 110
 111         err = inet_sk_diag_fill(sk, NULL, rep, r,
 112                                 sk_user_ns(NETLINK_CB(in_skb).sk),
 113                                 NETLINK_CB(in_skb).portid,
 114                                 nlh->nlmsg_seq, 0, nlh,
 115                                 netlink_net_capable(in_skb, CAP_NET_ADMIN));
 116         sock_put(sk);
 117
 118         if (err < 0) {
 119                 kfree_skb(rep);
 120                 return err;
 121         }
 122
 123         err = netlink_unicast(net->diag_nlsk, rep,
 124                               NETLINK_CB(in_skb).portid,
 125                               MSG_DONTWAIT);
 126         if (err > 0)
 127                 err = 0;
 128         return err;
 129 }
 130
 131 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
 132                         struct netlink_callback *cb,
 133                         const struct inet_diag_req_v2 *r,
 134                         struct nlattr *bc, bool net_admin)
 135 {
 136         if (!inet_diag_bc_sk(bc, sk))
 137                 return 0;
 138
 139         return inet_sk_diag_fill(sk, NULL, skb, r,
 140                                  sk_user_ns(NETLINK_CB(cb->skb).sk),
 141                                  NETLINK_CB(cb->skb).portid,
 142                                  cb->nlh->nlmsg_seq, NLM_F_MULTI,
 143                                  cb->nlh, net_admin);
 144 }
 145
 146 static void raw_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 147                           const struct inet_diag_req_v2 *r, struct nlattr *bc)
 148 {
 149         bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
 150         struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
 151         struct net *net = sock_net(skb->sk);
 152         int num, s_num, slot, s_slot;
 153         struct sock *sk = NULL;
 154
 155         if (IS_ERR(hashinfo))
 156                 return;
 157
 158         s_slot = cb->args[0];
 159         num = s_num = cb->args[1];
 160
 161         read_lock(&hashinfo->lock);
 162         for (slot = s_slot; slot < RAW_HTABLE_SIZE; s_num = 0, slot++) {
 163                 num = 0;
 164
 165                 sk_for_each(sk, &hashinfo->ht[slot]) {
 166                         struct inet_sock *inet = inet_sk(sk);
 167
 168                         if (!net_eq(sock_net(sk), net))
 169                                 continue;
 170                         if (num < s_num)
 171                                 goto next;
 172                         if (sk->sk_family != r->sdiag_family)
 173                                 goto next;
 174                         if (r->id.idiag_sport != inet->inet_sport &&
 175                             r->id.idiag_sport)
 176                                 goto next;
 177                         if (r->id.idiag_dport != inet->inet_dport &&
 178                             r->id.idiag_dport)
 179                                 goto next;
 180                         if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0)
 181                                 goto out_unlock;
 182 next:
 183                         num++;
 184                 }
 185         }
 186
 187 out_unlock:
 188         read_unlock(&hashinfo->lock);
 189
 190         cb->args[0] = slot;
 191         cb->args[1] = num;
 192 }
 193
 194 static void raw_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
 195                               void *info)
 196 {
 197         r->idiag_rqueue = sk_rmem_alloc_get(sk);
 198         r->idiag_wqueue = sk_wmem_alloc_get(sk);
 199 }
 200
 201 #ifdef CONFIG_INET_DIAG_DESTROY
 202 static int raw_diag_destroy(struct sk_buff *in_skb,
 203                             const struct inet_diag_req_v2 *r)
 204 {
 205         struct net *net = sock_net(in_skb->sk);
 206         struct sock *sk;
 207         int err;
 208
 209         sk = raw_sock_get(net, r);
 210         if (IS_ERR(sk))
 211                 return PTR_ERR(sk);
 212         err = sock_diag_destroy(sk, ECONNABORTED);
 213         sock_put(sk);
 214         return err;
 215 }
 216 #endif
 217
 218 static const struct inet_diag_handler raw_diag_handler = {
 219         .dump                   = raw_diag_dump,
 220         .dump_one               = raw_diag_dump_one,
 221         .idiag_get_info         = raw_diag_get_info,
 222         .idiag_type             = IPPROTO_RAW,
 223         .idiag_info_size        = 0,
 224 #ifdef CONFIG_INET_DIAG_DESTROY
 225         .destroy                = raw_diag_destroy,
 226 #endif
 227 };
 228
 229 static void __always_unused __check_inet_diag_req_raw(void)
 230 {
 231         /*
 232          * Make sure the two structures are identical,
 233          * except the @pad field.
 234          */
 235 #define __offset_mismatch(m1, m2)                       \
 236         (offsetof(struct inet_diag_req_v2, m1) !=       \
 237          offsetof(struct inet_diag_req_raw, m2))
 238
 239         BUILD_BUG_ON(sizeof(struct inet_diag_req_v2) !=
 240                      sizeof(struct inet_diag_req_raw));
 241         BUILD_BUG_ON(__offset_mismatch(sdiag_family, sdiag_family));
 242         BUILD_BUG_ON(__offset_mismatch(sdiag_protocol, sdiag_protocol));
 243         BUILD_BUG_ON(__offset_mismatch(idiag_ext, idiag_ext));
 244         BUILD_BUG_ON(__offset_mismatch(pad, sdiag_raw_protocol));
 245         BUILD_BUG_ON(__offset_mismatch(idiag_states, idiag_states));
 246         BUILD_BUG_ON(__offset_mismatch(id, id));
 247 #undef __offset_mismatch
 248 }
 249
 250 static int __init raw_diag_init(void)
 251 {
 252         return inet_diag_register(&raw_diag_handler);
 253 }
 254
 255 static void __exit raw_diag_exit(void)
 256 {
 257         inet_diag_unregister(&raw_diag_handler);
 258 }
 259
 260 module_init(raw_diag_init);
 261 module_exit(raw_diag_exit);
 262 MODULE_LICENSE("GPL");
 263 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-255 /* AF_INET - IPPROTO_RAW */);
 264 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10-255 /* AF_INET6 - IPPROTO_RAW */);