net/ipv4/raw_diag.c

   1 #include <linux/module.h>
   2
   3 #include <linux/inet_diag.h>
   4 #include <linux/sock_diag.h>
   5
   6 #include <net/inet_sock.h>
   7 #include <net/raw.h>
   8 #include <net/rawv6.h>
   9
  10 #ifdef pr_fmt
  11 # undef pr_fmt
  12 #endif
  13
  14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16 static struct raw_hashinfo *
  17 raw_get_hashinfo(const struct inet_diag_req_v2 *r)
  18 {
  19         if (r->sdiag_family == AF_INET) {
  20                 return &raw_v4_hashinfo;
  21 #if IS_ENABLED(CONFIG_IPV6)
  22         } else if (r->sdiag_family == AF_INET6) {
  23                 return &raw_v6_hashinfo;
  24 #endif
  25         } else {
  26                 pr_warn_once("Unexpected inet family %d\n",
  27                              r->sdiag_family);
  28                 WARN_ON_ONCE(1);
  29                 return ERR_PTR(-EINVAL);
  30         }
  31 }
  32
  33 /*
  34  * Due to requirement of not breaking user API we can't simply
  35  * rename @pad field in inet_diag_req_v2 structure, instead
  36  * use helper to figure it out.
  37  */
  38
  39 static struct sock *raw_lookup(struct net *net, struct sock *from,
  40                                const struct inet_diag_req_v2 *req)
  41 {
  42         struct inet_diag_req_raw *r = (void *)req;
  43         struct sock *sk = NULL;
  44
  45         if (r->sdiag_family == AF_INET)
  46                 sk = __raw_v4_lookup(net, from, r->sdiag_raw_protocol,
  47                                      r->id.idiag_dst[0],
  48                                      r->id.idiag_src[0],
  49                                      r->id.idiag_if, 0);
  50 #if IS_ENABLED(CONFIG_IPV6)
  51         else
  52                 sk = __raw_v6_lookup(net, from, r->sdiag_raw_protocol,
  53                                      (const struct in6_addr *)r->id.idiag_src,
  54                                      (const struct in6_addr *)r->id.idiag_dst,
  55                                      r->id.idiag_if, 0);
  56 #endif
  57         return sk;
  58 }
  59
  60 static struct sock *raw_sock_get(struct net *net, const struct inet_diag_req_v2 *r)
  61 {
  62         struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
  63         struct sock *sk = NULL, *s;
  64         int slot;
  65
  66         if (IS_ERR(hashinfo))
  67                 return ERR_CAST(hashinfo);
  68
  69         read_lock(&hashinfo->lock);
  70         for (slot = 0; slot < RAW_HTABLE_SIZE; slot++) {
  71                 sk_for_each(s, &hashinfo->ht[slot]) {
  72                         sk = raw_lookup(net, s, r);
  73                         if (sk) {
  74                                 /*
  75                                  * Grab it and keep until we fill
  76                                  * diag meaage to be reported, so
  77                                  * caller should call sock_put then.
  78                                  * We can do that because we're keeping
  79                                  * hashinfo->lock here.
  80                                  */
  81                                 sock_hold(sk);
  82                                 goto out_unlock;
  83                         }
  84                 }
  85         }
  86 out_unlock:
  87         read_unlock(&hashinfo->lock);
  88
  89         return sk ? sk : ERR_PTR(-ENOENT);
  90 }
  91
  92 static int raw_diag_dump_one(struct sk_buff *in_skb,
  93                              const struct nlmsghdr *nlh,
  94                              const struct inet_diag_req_v2 *r)
  95 {
  96         struct net *net = sock_net(in_skb->sk);
  97         struct sk_buff *rep;
  98         struct sock *sk;
  99         int err;
 100
 101         sk = raw_sock_get(net, r);
 102         if (IS_ERR(sk))
 103                 return PTR_ERR(sk);
 104
 105         rep = nlmsg_new(sizeof(struct inet_diag_msg) +
 106                         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, r,
 114                                 sk_user_ns(NETLINK_CB(in_skb).sk),
 115                                 NETLINK_CB(in_skb).portid,
 116                                 nlh->nlmsg_seq, 0, nlh,
 117                                 netlink_net_capable(in_skb, CAP_NET_ADMIN));
 118         sock_put(sk);
 119
 120         if (err < 0) {
 121                 kfree_skb(rep);
 122                 return err;
 123         }
 124
 125         err = netlink_unicast(net->diag_nlsk, rep,
 126                               NETLINK_CB(in_skb).portid,
 127                               MSG_DONTWAIT);
 128         if (err > 0)
 129                 err = 0;
 130         return err;
 131 }
 132
 133 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
 134                         struct netlink_callback *cb,
 135                         const struct inet_diag_req_v2 *r,
 136                         struct nlattr *bc, bool net_admin)
 137 {
 138         if (!inet_diag_bc_sk(bc, sk))
 139                 return 0;
 140
 141         return inet_sk_diag_fill(sk, NULL, skb, r,
 142                                  sk_user_ns(NETLINK_CB(cb->skb).sk),
 143                                  NETLINK_CB(cb->skb).portid,
 144                                  cb->nlh->nlmsg_seq, NLM_F_MULTI,
 145                                  cb->nlh, net_admin);
 146 }
 147
 148 static void raw_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 149                           const struct inet_diag_req_v2 *r, struct nlattr *bc)
 150 {
 151         bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
 152         struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
 153         struct net *net = sock_net(skb->sk);
 154         int num, s_num, slot, s_slot;
 155         struct sock *sk = NULL;
 156
 157         if (IS_ERR(hashinfo))
 158                 return;
 159
 160         s_slot = cb->args[0];
 161         num = s_num = cb->args[1];
 162
 163         read_lock(&hashinfo->lock);
 164         for (slot = s_slot; slot < RAW_HTABLE_SIZE; s_num = 0, slot++) {
 165                 num = 0;
 166
 167                 sk_for_each(sk, &hashinfo->ht[slot]) {
 168                         struct inet_sock *inet = inet_sk(sk);
 169
 170                         if (!net_eq(sock_net(sk), net))
 171                                 continue;
 172                         if (num < s_num)
 173                                 goto next;
 174                         if (sk->sk_family != r->sdiag_family)
 175                                 goto next;
 176                         if (r->id.idiag_sport != inet->inet_sport &&
 177                             r->id.idiag_sport)
 178                                 goto next;
 179                         if (r->id.idiag_dport != inet->inet_dport &&
 180                             r->id.idiag_dport)
 181                                 goto next;
 182                         if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0)
 183                                 goto out_unlock;
 184 next:
 185                         num++;
 186                 }
 187         }
 188
 189 out_unlock:
 190         read_unlock(&hashinfo->lock);
 191
 192         cb->args[0] = slot;
 193         cb->args[1] = num;
 194 }
 195
 196 static void raw_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
 197                               void *info)
 198 {
 199         r->idiag_rqueue = sk_rmem_alloc_get(sk);
 200         r->idiag_wqueue = sk_wmem_alloc_get(sk);
 201 }
 202
 203 #ifdef CONFIG_INET_DIAG_DESTROY
 204 static int raw_diag_destroy(struct sk_buff *in_skb,
 205                             const struct inet_diag_req_v2 *r)
 206 {
 207         struct net *net = sock_net(in_skb->sk);
 208         struct sock *sk;
 209         int err;
 210
 211         sk = raw_sock_get(net, r);
 212         if (IS_ERR(sk))
 213                 return PTR_ERR(sk);
 214         err = sock_diag_destroy(sk, ECONNABORTED);
 215         sock_put(sk);
 216         return err;
 217 }
 218 #endif
 219
 220 static const struct inet_diag_handler raw_diag_handler = {
 221         .dump                   = raw_diag_dump,
 222         .dump_one               = raw_diag_dump_one,
 223         .idiag_get_info         = raw_diag_get_info,
 224         .idiag_type             = IPPROTO_RAW,
 225         .idiag_info_size        = 0,
 226 #ifdef CONFIG_INET_DIAG_DESTROY
 227         .destroy                = raw_diag_destroy,
 228 #endif
 229 };
 230
 231 static void __always_unused __check_inet_diag_req_raw(void)
 232 {
 233         /*
 234          * Make sure the two structures are identical,
 235          * except the @pad field.
 236          */
 237 #define __offset_mismatch(m1, m2)                       \
 238         (offsetof(struct inet_diag_req_v2, m1) !=       \
 239          offsetof(struct inet_diag_req_raw, m2))
 240
 241         BUILD_BUG_ON(sizeof(struct inet_diag_req_v2) !=
 242                      sizeof(struct inet_diag_req_raw));
 243         BUILD_BUG_ON(__offset_mismatch(sdiag_family, sdiag_family));
 244         BUILD_BUG_ON(__offset_mismatch(sdiag_protocol, sdiag_protocol));
 245         BUILD_BUG_ON(__offset_mismatch(idiag_ext, idiag_ext));
 246         BUILD_BUG_ON(__offset_mismatch(pad, sdiag_raw_protocol));
 247         BUILD_BUG_ON(__offset_mismatch(idiag_states, idiag_states));
 248         BUILD_BUG_ON(__offset_mismatch(id, id));
 249 #undef __offset_mismatch
 250 }
 251
 252 static int __init raw_diag_init(void)
 253 {
 254         return inet_diag_register(&raw_diag_handler);
 255 }
 256
 257 static void __exit raw_diag_exit(void)
 258 {
 259         inet_diag_unregister(&raw_diag_handler);
 260 }
 261
 262 module_init(raw_diag_init);
 263 module_exit(raw_diag_exit);
 264 MODULE_LICENSE("GPL");
 265 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-255 /* AF_INET - IPPROTO_RAW */);
 266 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10-255 /* AF_INET6 - IPPROTO_RAW */);