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 *
raw_get_hashinfo(const struct inet_diag_req_v2 * r)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
raw_lookup(struct net * net,const struct sock * sk,const struct inet_diag_req_v2 * req)37 static bool raw_lookup(struct net *net, const 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
raw_sock_get(struct net * net,const struct inet_diag_req_v2 * r)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_head *hlist;
61 struct sock *sk;
62 int slot;
63
64 if (IS_ERR(hashinfo))
65 return ERR_CAST(hashinfo);
66
67 rcu_read_lock();
68 for (slot = 0; slot < RAW_HTABLE_SIZE; slot++) {
69 hlist = &hashinfo->ht[slot];
70 sk_for_each_rcu(sk, hlist) {
71 if (raw_lookup(net, sk, r)) {
72 /*
73 * Grab it and keep until we fill
74 * diag message to be reported, so
75 * caller should call sock_put then.
76 */
77 if (refcount_inc_not_zero(&sk->sk_refcnt))
78 goto out_unlock;
79 }
80 }
81 }
82 sk = ERR_PTR(-ENOENT);
83 out_unlock:
84 rcu_read_unlock();
85
86 return sk;
87 }
88
raw_diag_dump_one(struct netlink_callback * cb,const struct inet_diag_req_v2 * r)89 static int raw_diag_dump_one(struct netlink_callback *cb,
90 const struct inet_diag_req_v2 *r)
91 {
92 struct sk_buff *in_skb = cb->skb;
93 struct sk_buff *rep;
94 struct sock *sk;
95 struct net *net;
96 int err;
97
98 net = sock_net(in_skb->sk);
99 sk = raw_sock_get(net, r);
100 if (IS_ERR(sk))
101 return PTR_ERR(sk);
102
103 rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) +
104 inet_diag_msg_attrs_size() +
105 nla_total_size(sizeof(struct inet_diag_meminfo)) + 64,
106 GFP_KERNEL);
107 if (!rep) {
108 sock_put(sk);
109 return -ENOMEM;
110 }
111
112 err = inet_sk_diag_fill(sk, NULL, rep, cb, r, 0,
113 netlink_net_capable(in_skb, CAP_NET_ADMIN));
114 sock_put(sk);
115
116 if (err < 0) {
117 kfree_skb(rep);
118 return err;
119 }
120
121 err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid);
122
123 return err;
124 }
125
sk_diag_dump(struct sock * sk,struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * r,struct nlattr * bc,bool net_admin)126 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
127 struct netlink_callback *cb,
128 const struct inet_diag_req_v2 *r,
129 struct nlattr *bc, bool net_admin)
130 {
131 if (!inet_diag_bc_sk(bc, sk))
132 return 0;
133
134 return inet_sk_diag_fill(sk, NULL, skb, cb, r, NLM_F_MULTI, net_admin);
135 }
136
raw_diag_dump(struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * r)137 static void raw_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
138 const struct inet_diag_req_v2 *r)
139 {
140 bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
141 struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
142 struct net *net = sock_net(skb->sk);
143 struct inet_diag_dump_data *cb_data;
144 int num, s_num, slot, s_slot;
145 struct hlist_head *hlist;
146 struct sock *sk = NULL;
147 struct nlattr *bc;
148
149 if (IS_ERR(hashinfo))
150 return;
151
152 cb_data = cb->data;
153 bc = cb_data->inet_diag_nla_bc;
154 s_slot = cb->args[0];
155 num = s_num = cb->args[1];
156
157 rcu_read_lock();
158 for (slot = s_slot; slot < RAW_HTABLE_SIZE; s_num = 0, slot++) {
159 num = 0;
160
161 hlist = &hashinfo->ht[slot];
162 sk_for_each_rcu(sk, hlist) {
163 struct inet_sock *inet = inet_sk(sk);
164
165 if (!net_eq(sock_net(sk), net))
166 continue;
167 if (num < s_num)
168 goto next;
169 if (sk->sk_family != r->sdiag_family)
170 goto next;
171 if (r->id.idiag_sport != inet->inet_sport &&
172 r->id.idiag_sport)
173 goto next;
174 if (r->id.idiag_dport != inet->inet_dport &&
175 r->id.idiag_dport)
176 goto next;
177 if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0)
178 goto out_unlock;
179 next:
180 num++;
181 }
182 }
183
184 out_unlock:
185 rcu_read_unlock();
186
187 cb->args[0] = slot;
188 cb->args[1] = num;
189 }
190
raw_diag_get_info(struct sock * sk,struct inet_diag_msg * r,void * info)191 static void raw_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
192 void *info)
193 {
194 r->idiag_rqueue = sk_rmem_alloc_get(sk);
195 r->idiag_wqueue = sk_wmem_alloc_get(sk);
196 }
197
198 #ifdef CONFIG_INET_DIAG_DESTROY
raw_diag_destroy(struct sk_buff * in_skb,const struct inet_diag_req_v2 * r)199 static int raw_diag_destroy(struct sk_buff *in_skb,
200 const struct inet_diag_req_v2 *r)
201 {
202 struct net *net = sock_net(in_skb->sk);
203 struct sock *sk;
204 int err;
205
206 sk = raw_sock_get(net, r);
207 if (IS_ERR(sk))
208 return PTR_ERR(sk);
209 err = sock_diag_destroy(sk, ECONNABORTED);
210 sock_put(sk);
211 return err;
212 }
213 #endif
214
215 static const struct inet_diag_handler raw_diag_handler = {
216 .owner = THIS_MODULE,
217 .dump = raw_diag_dump,
218 .dump_one = raw_diag_dump_one,
219 .idiag_get_info = raw_diag_get_info,
220 .idiag_type = IPPROTO_RAW,
221 .idiag_info_size = 0,
222 #ifdef CONFIG_INET_DIAG_DESTROY
223 .destroy = raw_diag_destroy,
224 #endif
225 };
226
__check_inet_diag_req_raw(void)227 static void __always_unused __check_inet_diag_req_raw(void)
228 {
229 /*
230 * Make sure the two structures are identical,
231 * except the @pad field.
232 */
233 #define __offset_mismatch(m1, m2) \
234 (offsetof(struct inet_diag_req_v2, m1) != \
235 offsetof(struct inet_diag_req_raw, m2))
236
237 BUILD_BUG_ON(sizeof(struct inet_diag_req_v2) !=
238 sizeof(struct inet_diag_req_raw));
239 BUILD_BUG_ON(__offset_mismatch(sdiag_family, sdiag_family));
240 BUILD_BUG_ON(__offset_mismatch(sdiag_protocol, sdiag_protocol));
241 BUILD_BUG_ON(__offset_mismatch(idiag_ext, idiag_ext));
242 BUILD_BUG_ON(__offset_mismatch(pad, sdiag_raw_protocol));
243 BUILD_BUG_ON(__offset_mismatch(idiag_states, idiag_states));
244 BUILD_BUG_ON(__offset_mismatch(id, id));
245 #undef __offset_mismatch
246 }
247
raw_diag_init(void)248 static int __init raw_diag_init(void)
249 {
250 return inet_diag_register(&raw_diag_handler);
251 }
252
raw_diag_exit(void)253 static void __exit raw_diag_exit(void)
254 {
255 inet_diag_unregister(&raw_diag_handler);
256 }
257
258 module_init(raw_diag_init);
259 module_exit(raw_diag_exit);
260 MODULE_LICENSE("GPL");
261 MODULE_DESCRIPTION("RAW socket monitoring via SOCK_DIAG");
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 */);
264