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