1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | #include <linux/module.h> |
3 | |
4 | #include <net/sock.h> |
5 | #include <linux/netlink.h> |
6 | #include <linux/sock_diag.h> |
7 | #include <linux/netlink_diag.h> |
8 | #include <linux/rhashtable.h> |
9 | |
10 | #include "af_netlink.h" |
11 | |
12 | static int sk_diag_dump_groups(struct sock *sk, struct sk_buff *nlskb) |
13 | { |
14 | struct netlink_sock *nlk = nlk_sk(sk); |
15 | |
16 | if (nlk->groups == NULL) |
17 | return 0; |
18 | |
19 | return nla_put(skb: nlskb, attrtype: NETLINK_DIAG_GROUPS, NLGRPSZ(nlk->ngroups), |
20 | data: nlk->groups); |
21 | } |
22 | |
23 | static int sk_diag_put_flags(struct sock *sk, struct sk_buff *skb) |
24 | { |
25 | struct netlink_sock *nlk = nlk_sk(sk); |
26 | u32 flags = 0; |
27 | |
28 | if (nlk->cb_running) |
29 | flags |= NDIAG_FLAG_CB_RUNNING; |
30 | if (nlk_test_bit(RECV_PKTINFO, sk)) |
31 | flags |= NDIAG_FLAG_PKTINFO; |
32 | if (nlk_test_bit(BROADCAST_SEND_ERROR, sk)) |
33 | flags |= NDIAG_FLAG_BROADCAST_ERROR; |
34 | if (nlk_test_bit(RECV_NO_ENOBUFS, sk)) |
35 | flags |= NDIAG_FLAG_NO_ENOBUFS; |
36 | if (nlk_test_bit(LISTEN_ALL_NSID, sk)) |
37 | flags |= NDIAG_FLAG_LISTEN_ALL_NSID; |
38 | if (nlk_test_bit(CAP_ACK, sk)) |
39 | flags |= NDIAG_FLAG_CAP_ACK; |
40 | |
41 | return nla_put_u32(skb, attrtype: NETLINK_DIAG_FLAGS, value: flags); |
42 | } |
43 | |
44 | static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, |
45 | struct netlink_diag_req *req, |
46 | u32 portid, u32 seq, u32 flags, int sk_ino) |
47 | { |
48 | struct nlmsghdr *nlh; |
49 | struct netlink_diag_msg *rep; |
50 | struct netlink_sock *nlk = nlk_sk(sk); |
51 | |
52 | nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, payload: sizeof(*rep), |
53 | flags); |
54 | if (!nlh) |
55 | return -EMSGSIZE; |
56 | |
57 | rep = nlmsg_data(nlh); |
58 | rep->ndiag_family = AF_NETLINK; |
59 | rep->ndiag_type = sk->sk_type; |
60 | rep->ndiag_protocol = sk->sk_protocol; |
61 | rep->ndiag_state = sk->sk_state; |
62 | |
63 | rep->ndiag_ino = sk_ino; |
64 | rep->ndiag_portid = nlk->portid; |
65 | rep->ndiag_dst_portid = nlk->dst_portid; |
66 | rep->ndiag_dst_group = nlk->dst_group; |
67 | sock_diag_save_cookie(sk, cookie: rep->ndiag_cookie); |
68 | |
69 | if ((req->ndiag_show & NDIAG_SHOW_GROUPS) && |
70 | sk_diag_dump_groups(sk, nlskb: skb)) |
71 | goto out_nlmsg_trim; |
72 | |
73 | if ((req->ndiag_show & NDIAG_SHOW_MEMINFO) && |
74 | sock_diag_put_meminfo(sk, skb, attr: NETLINK_DIAG_MEMINFO)) |
75 | goto out_nlmsg_trim; |
76 | |
77 | if ((req->ndiag_show & NDIAG_SHOW_FLAGS) && |
78 | sk_diag_put_flags(sk, skb)) |
79 | goto out_nlmsg_trim; |
80 | |
81 | nlmsg_end(skb, nlh); |
82 | return 0; |
83 | |
84 | out_nlmsg_trim: |
85 | nlmsg_cancel(skb, nlh); |
86 | return -EMSGSIZE; |
87 | } |
88 | |
89 | static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, |
90 | int protocol, int s_num) |
91 | { |
92 | struct rhashtable_iter *hti = (void *)cb->args[2]; |
93 | struct netlink_table *tbl = &nl_table[protocol]; |
94 | struct net *net = sock_net(sk: skb->sk); |
95 | struct netlink_diag_req *req; |
96 | struct netlink_sock *nlsk; |
97 | unsigned long flags; |
98 | struct sock *sk; |
99 | int num = 2; |
100 | int ret = 0; |
101 | |
102 | req = nlmsg_data(nlh: cb->nlh); |
103 | |
104 | if (s_num > 1) |
105 | goto mc_list; |
106 | |
107 | num--; |
108 | |
109 | if (!hti) { |
110 | hti = kmalloc(size: sizeof(*hti), GFP_KERNEL); |
111 | if (!hti) |
112 | return -ENOMEM; |
113 | |
114 | cb->args[2] = (long)hti; |
115 | } |
116 | |
117 | if (!s_num) |
118 | rhashtable_walk_enter(ht: &tbl->hash, iter: hti); |
119 | |
120 | rhashtable_walk_start(iter: hti); |
121 | |
122 | while ((nlsk = rhashtable_walk_next(iter: hti))) { |
123 | if (IS_ERR(ptr: nlsk)) { |
124 | ret = PTR_ERR(ptr: nlsk); |
125 | if (ret == -EAGAIN) { |
126 | ret = 0; |
127 | continue; |
128 | } |
129 | break; |
130 | } |
131 | |
132 | sk = (struct sock *)nlsk; |
133 | |
134 | if (!net_eq(net1: sock_net(sk), net2: net)) |
135 | continue; |
136 | |
137 | if (sk_diag_fill(sk, skb, req, |
138 | NETLINK_CB(cb->skb).portid, |
139 | seq: cb->nlh->nlmsg_seq, |
140 | NLM_F_MULTI, |
141 | sk_ino: sock_i_ino(sk)) < 0) { |
142 | ret = 1; |
143 | break; |
144 | } |
145 | } |
146 | |
147 | rhashtable_walk_stop(iter: hti); |
148 | |
149 | if (ret) |
150 | goto done; |
151 | |
152 | rhashtable_walk_exit(iter: hti); |
153 | num++; |
154 | |
155 | mc_list: |
156 | read_lock_irqsave(&nl_table_lock, flags); |
157 | sk_for_each_bound(sk, &tbl->mc_list) { |
158 | if (sk_hashed(sk)) |
159 | continue; |
160 | if (!net_eq(net1: sock_net(sk), net2: net)) |
161 | continue; |
162 | if (num < s_num) { |
163 | num++; |
164 | continue; |
165 | } |
166 | |
167 | if (sk_diag_fill(sk, skb, req, |
168 | NETLINK_CB(cb->skb).portid, |
169 | seq: cb->nlh->nlmsg_seq, |
170 | NLM_F_MULTI, |
171 | sk_ino: __sock_i_ino(sk)) < 0) { |
172 | ret = 1; |
173 | break; |
174 | } |
175 | num++; |
176 | } |
177 | read_unlock_irqrestore(&nl_table_lock, flags); |
178 | |
179 | done: |
180 | cb->args[0] = num; |
181 | |
182 | return ret; |
183 | } |
184 | |
185 | static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) |
186 | { |
187 | struct netlink_diag_req *req; |
188 | int s_num = cb->args[0]; |
189 | int err = 0; |
190 | |
191 | req = nlmsg_data(nlh: cb->nlh); |
192 | |
193 | if (req->sdiag_protocol == NDIAG_PROTO_ALL) { |
194 | int i; |
195 | |
196 | for (i = cb->args[1]; i < MAX_LINKS; i++) { |
197 | err = __netlink_diag_dump(skb, cb, protocol: i, s_num); |
198 | if (err) |
199 | break; |
200 | s_num = 0; |
201 | } |
202 | cb->args[1] = i; |
203 | } else { |
204 | if (req->sdiag_protocol >= MAX_LINKS) |
205 | return -ENOENT; |
206 | |
207 | err = __netlink_diag_dump(skb, cb, protocol: req->sdiag_protocol, s_num); |
208 | } |
209 | |
210 | return err < 0 ? err : skb->len; |
211 | } |
212 | |
213 | static int netlink_diag_dump_done(struct netlink_callback *cb) |
214 | { |
215 | struct rhashtable_iter *hti = (void *)cb->args[2]; |
216 | |
217 | if (cb->args[0] == 1) |
218 | rhashtable_walk_exit(iter: hti); |
219 | |
220 | kfree(objp: hti); |
221 | |
222 | return 0; |
223 | } |
224 | |
225 | static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h) |
226 | { |
227 | int hdrlen = sizeof(struct netlink_diag_req); |
228 | struct net *net = sock_net(sk: skb->sk); |
229 | |
230 | if (nlmsg_len(nlh: h) < hdrlen) |
231 | return -EINVAL; |
232 | |
233 | if (h->nlmsg_flags & NLM_F_DUMP) { |
234 | struct netlink_dump_control c = { |
235 | .dump = netlink_diag_dump, |
236 | .done = netlink_diag_dump_done, |
237 | }; |
238 | return netlink_dump_start(ssk: net->diag_nlsk, skb, nlh: h, control: &c); |
239 | } else |
240 | return -EOPNOTSUPP; |
241 | } |
242 | |
243 | static const struct sock_diag_handler netlink_diag_handler = { |
244 | .family = AF_NETLINK, |
245 | .dump = netlink_diag_handler_dump, |
246 | }; |
247 | |
248 | static int __init netlink_diag_init(void) |
249 | { |
250 | return sock_diag_register(h: &netlink_diag_handler); |
251 | } |
252 | |
253 | static void __exit netlink_diag_exit(void) |
254 | { |
255 | sock_diag_unregister(h: &netlink_diag_handler); |
256 | } |
257 | |
258 | module_init(netlink_diag_init); |
259 | module_exit(netlink_diag_exit); |
260 | MODULE_LICENSE("GPL" ); |
261 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 16 /* AF_NETLINK */); |
262 | |