1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/module.h>
3 #include <linux/sock_diag.h>
4 #include <linux/net.h>
5 #include <linux/netdevice.h>
6 #include <linux/packet_diag.h>
7 #include <linux/percpu.h>
8 #include <net/net_namespace.h>
9 #include <net/sock.h>
10
11 #include "internal.h"
12
13 static int pdiag_put_info(const struct packet_sock *po, struct sk_buff *nlskb)
14 {
15 struct packet_diag_info pinfo;
16
17 pinfo.pdi_index = po->ifindex;
18 pinfo.pdi_version = po->tp_version;
19 pinfo.pdi_reserve = po->tp_reserve;
20 pinfo.pdi_copy_thresh = READ_ONCE(po->copy_thresh);
21 pinfo.pdi_tstamp = READ_ONCE(po->tp_tstamp);
22
23 pinfo.pdi_flags = 0;
24 if (packet_sock_flag(po, PACKET_SOCK_RUNNING))
25 pinfo.pdi_flags |= PDI_RUNNING;
26 if (packet_sock_flag(po, PACKET_SOCK_AUXDATA))
27 pinfo.pdi_flags |= PDI_AUXDATA;
28 if (packet_sock_flag(po, PACKET_SOCK_ORIGDEV))
29 pinfo.pdi_flags |= PDI_ORIGDEV;
30 if (READ_ONCE(po->vnet_hdr_sz))
31 pinfo.pdi_flags |= PDI_VNETHDR;
32 if (packet_sock_flag(po, PACKET_SOCK_TP_LOSS))
33 pinfo.pdi_flags |= PDI_LOSS;
34
35 return nla_put(nlskb, PACKET_DIAG_INFO, sizeof(pinfo), &pinfo);
36 }
37
38 static int pdiag_put_mclist(const struct packet_sock *po, struct sk_buff *nlskb)
39 {
40 struct nlattr *mca;
41 struct packet_mclist *ml;
42
43 mca = nla_nest_start_noflag(nlskb, PACKET_DIAG_MCLIST);
44 if (!mca)
45 return -EMSGSIZE;
46
47 rtnl_lock();
48 for (ml = po->mclist; ml; ml = ml->next) {
49 struct packet_diag_mclist *dml;
50
51 dml = nla_reserve_nohdr(nlskb, sizeof(*dml));
52 if (!dml) {
53 rtnl_unlock();
54 nla_nest_cancel(nlskb, mca);
55 return -EMSGSIZE;
56 }
57
58 dml->pdmc_index = ml->ifindex;
59 dml->pdmc_type = ml->type;
60 dml->pdmc_alen = ml->alen;
61 dml->pdmc_count = ml->count;
62 BUILD_BUG_ON(sizeof(dml->pdmc_addr) != sizeof(ml->addr));
63 memcpy(dml->pdmc_addr, ml->addr, sizeof(ml->addr));
64 }
65
66 rtnl_unlock();
67 nla_nest_end(nlskb, mca);
68
69 return 0;
70 }
71
72 static int pdiag_put_ring(struct packet_ring_buffer *ring, int ver, int nl_type,
73 struct sk_buff *nlskb)
74 {
75 struct packet_diag_ring pdr;
76
77 if (!ring->pg_vec)
78 return 0;
79
80 pdr.pdr_block_size = ring->pg_vec_pages << PAGE_SHIFT;
81 pdr.pdr_block_nr = ring->pg_vec_len;
82 pdr.pdr_frame_size = ring->frame_size;
83 pdr.pdr_frame_nr = ring->frame_max + 1;
84
85 if (ver > TPACKET_V2) {
86 pdr.pdr_retire_tmo = ring->prb_bdqc.retire_blk_tov;
87 pdr.pdr_sizeof_priv = ring->prb_bdqc.blk_sizeof_priv;
88 pdr.pdr_features = ring->prb_bdqc.feature_req_word;
89 } else {
90 pdr.pdr_retire_tmo = 0;
91 pdr.pdr_sizeof_priv = 0;
92 pdr.pdr_features = 0;
93 }
94
95 return nla_put(nlskb, nl_type, sizeof(pdr), &pdr);
96 }
97
98 static int pdiag_put_rings_cfg(struct packet_sock *po, struct sk_buff *skb)
99 {
100 int ret;
101
102 mutex_lock(&po->pg_vec_lock);
103 ret = pdiag_put_ring(&po->rx_ring, po->tp_version,
104 PACKET_DIAG_RX_RING, skb);
105 if (!ret)
106 ret = pdiag_put_ring(&po->tx_ring, po->tp_version,
107 PACKET_DIAG_TX_RING, skb);
108 mutex_unlock(&po->pg_vec_lock);
109
110 return ret;
111 }
112
113 static int pdiag_put_fanout(struct packet_sock *po, struct sk_buff *nlskb)
114 {
115 int ret = 0;
116
117 mutex_lock(&fanout_mutex);
118 if (po->fanout) {
119 u32 val;
120
121 val = (u32)po->fanout->id | ((u32)po->fanout->type << 16);
122 ret = nla_put_u32(nlskb, PACKET_DIAG_FANOUT, val);
123 }
124 mutex_unlock(&fanout_mutex);
125
126 return ret;
127 }
128
129 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
130 struct packet_diag_req *req,
131 bool may_report_filterinfo,
132 struct user_namespace *user_ns,
133 u32 portid, u32 seq, u32 flags, int sk_ino)
134 {
135 struct nlmsghdr *nlh;
136 struct packet_diag_msg *rp;
137 struct packet_sock *po = pkt_sk(sk);
138
139 nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rp), flags);
140 if (!nlh)
141 return -EMSGSIZE;
142
143 rp = nlmsg_data(nlh);
144 rp->pdiag_family = AF_PACKET;
145 rp->pdiag_type = sk->sk_type;
146 rp->pdiag_num = ntohs(READ_ONCE(po->num));
147 rp->pdiag_ino = sk_ino;
148 sock_diag_save_cookie(sk, rp->pdiag_cookie);
149
150 if ((req->pdiag_show & PACKET_SHOW_INFO) &&
151 pdiag_put_info(po, skb))
152 goto out_nlmsg_trim;
153
154 if ((req->pdiag_show & PACKET_SHOW_INFO) &&
155 nla_put_u32(skb, PACKET_DIAG_UID,
156 from_kuid_munged(user_ns, sock_i_uid(sk))))
157 goto out_nlmsg_trim;
158
159 if ((req->pdiag_show & PACKET_SHOW_MCLIST) &&
160 pdiag_put_mclist(po, skb))
161 goto out_nlmsg_trim;
162
163 if ((req->pdiag_show & PACKET_SHOW_RING_CFG) &&
164 pdiag_put_rings_cfg(po, skb))
165 goto out_nlmsg_trim;
166
167 if ((req->pdiag_show & PACKET_SHOW_FANOUT) &&
168 pdiag_put_fanout(po, skb))
169 goto out_nlmsg_trim;
170
171 if ((req->pdiag_show & PACKET_SHOW_MEMINFO) &&
172 sock_diag_put_meminfo(sk, skb, PACKET_DIAG_MEMINFO))
173 goto out_nlmsg_trim;
174
175 if ((req->pdiag_show & PACKET_SHOW_FILTER) &&
176 sock_diag_put_filterinfo(may_report_filterinfo, sk, skb,
177 PACKET_DIAG_FILTER))
178 goto out_nlmsg_trim;
179
180 nlmsg_end(skb, nlh);
181 return 0;
182
183 out_nlmsg_trim:
184 nlmsg_cancel(skb, nlh);
185 return -EMSGSIZE;
186 }
187
188 static int packet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
189 {
190 int num = 0, s_num = cb->args[0];
191 struct packet_diag_req *req;
192 struct net *net;
193 struct sock *sk;
194 bool may_report_filterinfo;
195
196 net = sock_net(skb->sk);
197 req = nlmsg_data(cb->nlh);
198 may_report_filterinfo = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
199
200 mutex_lock(&net->packet.sklist_lock);
201 sk_for_each(sk, &net->packet.sklist) {
202 if (!net_eq(sock_net(sk), net))
203 continue;
204 if (num < s_num)
205 goto next;
206
207 if (sk_diag_fill(sk, skb, req,
208 may_report_filterinfo,
209 sk_user_ns(NETLINK_CB(cb->skb).sk),
210 NETLINK_CB(cb->skb).portid,
211 cb->nlh->nlmsg_seq, NLM_F_MULTI,
212 sock_i_ino(sk)) < 0)
213 goto done;
214 next:
215 num++;
216 }
217 done:
218 mutex_unlock(&net->packet.sklist_lock);
219 cb->args[0] = num;
220
221 return skb->len;
222 }
223
224 static int packet_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
225 {
226 int hdrlen = sizeof(struct packet_diag_req);
227 struct net *net = sock_net(skb->sk);
228 struct packet_diag_req *req;
229
230 if (nlmsg_len(h) < hdrlen)
231 return -EINVAL;
232
233 req = nlmsg_data(h);
234 /* Make it possible to support protocol filtering later */
235 if (req->sdiag_protocol)
236 return -EINVAL;
237
238 if (h->nlmsg_flags & NLM_F_DUMP) {
239 struct netlink_dump_control c = {
240 .dump = packet_diag_dump,
241 };
242 return netlink_dump_start(net->diag_nlsk, skb, h, &c);
243 } else
244 return -EOPNOTSUPP;
245 }
246
247 static const struct sock_diag_handler packet_diag_handler = {
248 .owner = THIS_MODULE,
249 .family = AF_PACKET,
250 .dump = packet_diag_handler_dump,
251 };
252
253 static int __init packet_diag_init(void)
254 {
255 return sock_diag_register(&packet_diag_handler);
256 }
257
258 static void __exit packet_diag_exit(void)
259 {
260 sock_diag_unregister(&packet_diag_handler);
261 }
262
263 module_init(packet_diag_init);
264 module_exit(packet_diag_exit);
265 MODULE_LICENSE("GPL");
266 MODULE_DESCRIPTION("PACKET socket monitoring via SOCK_DIAG");
267 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 17 /* AF_PACKET */);
268
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