LXR linux/net/ipv4/raw

   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
  17static struct raw_hashinfo *
  18raw_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
  37static 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
  58static 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        }
  84out_unlock:
  85        read_unlock(&hashinfo->lock);
  86
  87        return sk ? sk : ERR_PTR(-ENOENT);
  88}
  89
  90static 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
 131static 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
 146static 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;
 182next:
 183                        num++;
 184                }
 185        }
 186
 187out_unlock:
 188        read_unlock(&hashinfo->lock);
 189
 190        cb->args[0] = slot;
 191        cb->args[1] = num;
 192}
 193
 194static 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
 202static 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
 218static 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
 229static 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
 250static int __init raw_diag_init(void)
 251{
 252        return inet_diag_register(&raw_diag_handler);
 253}
 254
 255static void __exit raw_diag_exit(void)
 256{
 257        inet_diag_unregister(&raw_diag_handler);
 258}
 259
 260module_init(raw_diag_init);
 261module_exit(raw_diag_exit);
 262MODULE_LICENSE("GPL");
 263MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-255 /* AF_INET - IPPROTO_RAW */);
 264MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10-255 /* AF_INET6 - IPPROTO_RAW */);
 265