GNU Linux-libre 4.19.211-gnu1
[releases.git] / net / netlink / diag.c
1 #include <linux/module.h>
2
3 #include <net/sock.h>
4 #include <linux/netlink.h>
5 #include <linux/sock_diag.h>
6 #include <linux/netlink_diag.h>
7 #include <linux/rhashtable.h>
8
9 #include "af_netlink.h"
10
11 static int sk_diag_dump_groups(struct sock *sk, struct sk_buff *nlskb)
12 {
13         struct netlink_sock *nlk = nlk_sk(sk);
14
15         if (nlk->groups == NULL)
16                 return 0;
17
18         return nla_put(nlskb, NETLINK_DIAG_GROUPS, NLGRPSZ(nlk->ngroups),
19                        nlk->groups);
20 }
21
22 static int sk_diag_put_flags(struct sock *sk, struct sk_buff *skb)
23 {
24         struct netlink_sock *nlk = nlk_sk(sk);
25         u32 flags = 0;
26
27         if (nlk->cb_running)
28                 flags |= NDIAG_FLAG_CB_RUNNING;
29         if (nlk->flags & NETLINK_F_RECV_PKTINFO)
30                 flags |= NDIAG_FLAG_PKTINFO;
31         if (nlk->flags & NETLINK_F_BROADCAST_SEND_ERROR)
32                 flags |= NDIAG_FLAG_BROADCAST_ERROR;
33         if (nlk->flags & NETLINK_F_RECV_NO_ENOBUFS)
34                 flags |= NDIAG_FLAG_NO_ENOBUFS;
35         if (nlk->flags & NETLINK_F_LISTEN_ALL_NSID)
36                 flags |= NDIAG_FLAG_LISTEN_ALL_NSID;
37         if (nlk->flags & NETLINK_F_CAP_ACK)
38                 flags |= NDIAG_FLAG_CAP_ACK;
39
40         return nla_put_u32(skb, NETLINK_DIAG_FLAGS, flags);
41 }
42
43 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
44                         struct netlink_diag_req *req,
45                         u32 portid, u32 seq, u32 flags, int sk_ino)
46 {
47         struct nlmsghdr *nlh;
48         struct netlink_diag_msg *rep;
49         struct netlink_sock *nlk = nlk_sk(sk);
50
51         nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep),
52                         flags);
53         if (!nlh)
54                 return -EMSGSIZE;
55
56         rep = nlmsg_data(nlh);
57         rep->ndiag_family       = AF_NETLINK;
58         rep->ndiag_type         = sk->sk_type;
59         rep->ndiag_protocol     = sk->sk_protocol;
60         rep->ndiag_state        = sk->sk_state;
61
62         rep->ndiag_ino          = sk_ino;
63         rep->ndiag_portid       = nlk->portid;
64         rep->ndiag_dst_portid   = nlk->dst_portid;
65         rep->ndiag_dst_group    = nlk->dst_group;
66         sock_diag_save_cookie(sk, rep->ndiag_cookie);
67
68         if ((req->ndiag_show & NDIAG_SHOW_GROUPS) &&
69             sk_diag_dump_groups(sk, skb))
70                 goto out_nlmsg_trim;
71
72         if ((req->ndiag_show & NDIAG_SHOW_MEMINFO) &&
73             sock_diag_put_meminfo(sk, skb, NETLINK_DIAG_MEMINFO))
74                 goto out_nlmsg_trim;
75
76         if ((req->ndiag_show & NDIAG_SHOW_FLAGS) &&
77             sk_diag_put_flags(sk, skb))
78                 goto out_nlmsg_trim;
79
80         nlmsg_end(skb, nlh);
81         return 0;
82
83 out_nlmsg_trim:
84         nlmsg_cancel(skb, nlh);
85         return -EMSGSIZE;
86 }
87
88 static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
89                                 int protocol, int s_num)
90 {
91         struct rhashtable_iter *hti = (void *)cb->args[2];
92         struct netlink_table *tbl = &nl_table[protocol];
93         struct net *net = sock_net(skb->sk);
94         struct netlink_diag_req *req;
95         struct netlink_sock *nlsk;
96         struct sock *sk;
97         int num = 2;
98         int ret = 0;
99
100         req = nlmsg_data(cb->nlh);
101
102         if (s_num > 1)
103                 goto mc_list;
104
105         num--;
106
107         if (!hti) {
108                 hti = kmalloc(sizeof(*hti), GFP_KERNEL);
109                 if (!hti)
110                         return -ENOMEM;
111
112                 cb->args[2] = (long)hti;
113         }
114
115         if (!s_num)
116                 rhashtable_walk_enter(&tbl->hash, hti);
117
118         rhashtable_walk_start(hti);
119
120         while ((nlsk = rhashtable_walk_next(hti))) {
121                 if (IS_ERR(nlsk)) {
122                         ret = PTR_ERR(nlsk);
123                         if (ret == -EAGAIN) {
124                                 ret = 0;
125                                 continue;
126                         }
127                         break;
128                 }
129
130                 sk = (struct sock *)nlsk;
131
132                 if (!net_eq(sock_net(sk), net))
133                         continue;
134
135                 if (sk_diag_fill(sk, skb, req,
136                                  NETLINK_CB(cb->skb).portid,
137                                  cb->nlh->nlmsg_seq,
138                                  NLM_F_MULTI,
139                                  sock_i_ino(sk)) < 0) {
140                         ret = 1;
141                         break;
142                 }
143         }
144
145         rhashtable_walk_stop(hti);
146
147         if (ret)
148                 goto done;
149
150         rhashtable_walk_exit(hti);
151         num++;
152
153 mc_list:
154         read_lock(&nl_table_lock);
155         sk_for_each_bound(sk, &tbl->mc_list) {
156                 if (sk_hashed(sk))
157                         continue;
158                 if (!net_eq(sock_net(sk), net))
159                         continue;
160                 if (num < s_num) {
161                         num++;
162                         continue;
163                 }
164
165                 if (sk_diag_fill(sk, skb, req,
166                                  NETLINK_CB(cb->skb).portid,
167                                  cb->nlh->nlmsg_seq,
168                                  NLM_F_MULTI,
169                                  sock_i_ino(sk)) < 0) {
170                         ret = 1;
171                         break;
172                 }
173                 num++;
174         }
175         read_unlock(&nl_table_lock);
176
177 done:
178         cb->args[0] = num;
179
180         return ret;
181 }
182
183 static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
184 {
185         struct netlink_diag_req *req;
186         int s_num = cb->args[0];
187         int err = 0;
188
189         req = nlmsg_data(cb->nlh);
190
191         if (req->sdiag_protocol == NDIAG_PROTO_ALL) {
192                 int i;
193
194                 for (i = cb->args[1]; i < MAX_LINKS; i++) {
195                         err = __netlink_diag_dump(skb, cb, i, s_num);
196                         if (err)
197                                 break;
198                         s_num = 0;
199                 }
200                 cb->args[1] = i;
201         } else {
202                 if (req->sdiag_protocol >= MAX_LINKS)
203                         return -ENOENT;
204
205                 err = __netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num);
206         }
207
208         return err < 0 ? err : skb->len;
209 }
210
211 static int netlink_diag_dump_done(struct netlink_callback *cb)
212 {
213         struct rhashtable_iter *hti = (void *)cb->args[2];
214
215         if (cb->args[0] == 1)
216                 rhashtable_walk_exit(hti);
217
218         kfree(hti);
219
220         return 0;
221 }
222
223 static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
224 {
225         int hdrlen = sizeof(struct netlink_diag_req);
226         struct net *net = sock_net(skb->sk);
227
228         if (nlmsg_len(h) < hdrlen)
229                 return -EINVAL;
230
231         if (h->nlmsg_flags & NLM_F_DUMP) {
232                 struct netlink_dump_control c = {
233                         .dump = netlink_diag_dump,
234                         .done = netlink_diag_dump_done,
235                 };
236                 return netlink_dump_start(net->diag_nlsk, skb, h, &c);
237         } else
238                 return -EOPNOTSUPP;
239 }
240
241 static const struct sock_diag_handler netlink_diag_handler = {
242         .family = AF_NETLINK,
243         .dump = netlink_diag_handler_dump,
244 };
245
246 static int __init netlink_diag_init(void)
247 {
248         return sock_diag_register(&netlink_diag_handler);
249 }
250
251 static void __exit netlink_diag_exit(void)
252 {
253         sock_diag_unregister(&netlink_diag_handler);
254 }
255
256 module_init(netlink_diag_init);
257 module_exit(netlink_diag_exit);
258 MODULE_LICENSE("GPL");
259 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 16 /* AF_NETLINK */);