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
13static 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 = po->copy_thresh;
21 pinfo.pdi_tstamp = READ_ONCE(po->tp_tstamp);
22
23 pinfo.pdi_flags = 0;
24 if (packet_sock_flag(po, flag: PACKET_SOCK_RUNNING))
25 pinfo.pdi_flags |= PDI_RUNNING;
26 if (packet_sock_flag(po, flag: PACKET_SOCK_AUXDATA))
27 pinfo.pdi_flags |= PDI_AUXDATA;
28 if (packet_sock_flag(po, flag: 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, flag: PACKET_SOCK_TP_LOSS))
33 pinfo.pdi_flags |= PDI_LOSS;
34
35 return nla_put(skb: nlskb, attrtype: PACKET_DIAG_INFO, attrlen: sizeof(pinfo), data: &pinfo);
36}
37
38static 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(skb: nlskb, attrtype: 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(skb: nlskb, attrlen: sizeof(*dml));
52 if (!dml) {
53 rtnl_unlock();
54 nla_nest_cancel(skb: nlskb, start: 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(skb: nlskb, start: mca);
68
69 return 0;
70}
71
72static 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(skb: nlskb, attrtype: nl_type, attrlen: sizeof(pdr), data: &pdr);
96}
97
98static 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(ring: &po->rx_ring, ver: po->tp_version,
104 nl_type: PACKET_DIAG_RX_RING, nlskb: skb);
105 if (!ret)
106 ret = pdiag_put_ring(ring: &po->tx_ring, ver: po->tp_version,
107 nl_type: PACKET_DIAG_TX_RING, nlskb: skb);
108 mutex_unlock(lock: &po->pg_vec_lock);
109
110 return ret;
111}
112
113static 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(skb: nlskb, attrtype: PACKET_DIAG_FANOUT, value: val);
123 }
124 mutex_unlock(lock: &fanout_mutex);
125
126 return ret;
127}
128
129static 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, payload: 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, cookie: rp->pdiag_cookie);
149
150 if ((req->pdiag_show & PACKET_SHOW_INFO) &&
151 pdiag_put_info(po, nlskb: skb))
152 goto out_nlmsg_trim;
153
154 if ((req->pdiag_show & PACKET_SHOW_INFO) &&
155 nla_put_u32(skb, attrtype: PACKET_DIAG_UID,
156 value: from_kuid_munged(to: user_ns, uid: sock_i_uid(sk))))
157 goto out_nlmsg_trim;
158
159 if ((req->pdiag_show & PACKET_SHOW_MCLIST) &&
160 pdiag_put_mclist(po, nlskb: 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, nlskb: skb))
169 goto out_nlmsg_trim;
170
171 if ((req->pdiag_show & PACKET_SHOW_MEMINFO) &&
172 sock_diag_put_meminfo(sk, skb, attr: 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 attrtype: PACKET_DIAG_FILTER))
178 goto out_nlmsg_trim;
179
180 nlmsg_end(skb, nlh);
181 return 0;
182
183out_nlmsg_trim:
184 nlmsg_cancel(skb, nlh);
185 return -EMSGSIZE;
186}
187
188static 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(sk: skb->sk);
197 req = nlmsg_data(nlh: cb->nlh);
198 may_report_filterinfo = netlink_net_capable(skb: 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(net1: sock_net(sk), net2: 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 user_ns: sk_user_ns(NETLINK_CB(cb->skb).sk),
210 NETLINK_CB(cb->skb).portid,
211 seq: cb->nlh->nlmsg_seq, NLM_F_MULTI,
212 sk_ino: sock_i_ino(sk)) < 0)
213 goto done;
214next:
215 num++;
216 }
217done:
218 mutex_unlock(lock: &net->packet.sklist_lock);
219 cb->args[0] = num;
220
221 return skb->len;
222}
223
224static 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(sk: skb->sk);
228 struct packet_diag_req *req;
229
230 if (nlmsg_len(nlh: h) < hdrlen)
231 return -EINVAL;
232
233 req = nlmsg_data(nlh: 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(ssk: net->diag_nlsk, skb, nlh: h, control: &c);
243 } else
244 return -EOPNOTSUPP;
245}
246
247static const struct sock_diag_handler packet_diag_handler = {
248 .family = AF_PACKET,
249 .dump = packet_diag_handler_dump,
250};
251
252static int __init packet_diag_init(void)
253{
254 return sock_diag_register(h: &packet_diag_handler);
255}
256
257static void __exit packet_diag_exit(void)
258{
259 sock_diag_unregister(h: &packet_diag_handler);
260}
261
262module_init(packet_diag_init);
263module_exit(packet_diag_exit);
264MODULE_LICENSE("GPL");
265MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 17 /* AF_PACKET */);
266

source code of linux/net/packet/diag.c