xref: /openbmc/linux/net/packet/diag.c (revision 0d456bad)
1 #include <linux/module.h>
2 #include <linux/sock_diag.h>
3 #include <linux/net.h>
4 #include <linux/netdevice.h>
5 #include <linux/packet_diag.h>
6 #include <net/net_namespace.h>
7 #include <net/sock.h>
8 
9 #include "internal.h"
10 
11 static int pdiag_put_info(const struct packet_sock *po, struct sk_buff *nlskb)
12 {
13 	struct packet_diag_info pinfo;
14 
15 	pinfo.pdi_index = po->ifindex;
16 	pinfo.pdi_version = po->tp_version;
17 	pinfo.pdi_reserve = po->tp_reserve;
18 	pinfo.pdi_copy_thresh = po->copy_thresh;
19 	pinfo.pdi_tstamp = po->tp_tstamp;
20 
21 	pinfo.pdi_flags = 0;
22 	if (po->running)
23 		pinfo.pdi_flags |= PDI_RUNNING;
24 	if (po->auxdata)
25 		pinfo.pdi_flags |= PDI_AUXDATA;
26 	if (po->origdev)
27 		pinfo.pdi_flags |= PDI_ORIGDEV;
28 	if (po->has_vnet_hdr)
29 		pinfo.pdi_flags |= PDI_VNETHDR;
30 	if (po->tp_loss)
31 		pinfo.pdi_flags |= PDI_LOSS;
32 
33 	return nla_put(nlskb, PACKET_DIAG_INFO, sizeof(pinfo), &pinfo);
34 }
35 
36 static int pdiag_put_mclist(const struct packet_sock *po, struct sk_buff *nlskb)
37 {
38 	struct nlattr *mca;
39 	struct packet_mclist *ml;
40 
41 	mca = nla_nest_start(nlskb, PACKET_DIAG_MCLIST);
42 	if (!mca)
43 		return -EMSGSIZE;
44 
45 	rtnl_lock();
46 	for (ml = po->mclist; ml; ml = ml->next) {
47 		struct packet_diag_mclist *dml;
48 
49 		dml = nla_reserve_nohdr(nlskb, sizeof(*dml));
50 		if (!dml) {
51 			rtnl_unlock();
52 			nla_nest_cancel(nlskb, mca);
53 			return -EMSGSIZE;
54 		}
55 
56 		dml->pdmc_index = ml->ifindex;
57 		dml->pdmc_type = ml->type;
58 		dml->pdmc_alen = ml->alen;
59 		dml->pdmc_count = ml->count;
60 		BUILD_BUG_ON(sizeof(dml->pdmc_addr) != sizeof(ml->addr));
61 		memcpy(dml->pdmc_addr, ml->addr, sizeof(ml->addr));
62 	}
63 
64 	rtnl_unlock();
65 	nla_nest_end(nlskb, mca);
66 
67 	return 0;
68 }
69 
70 static int pdiag_put_ring(struct packet_ring_buffer *ring, int ver, int nl_type,
71 		struct sk_buff *nlskb)
72 {
73 	struct packet_diag_ring pdr;
74 
75 	if (!ring->pg_vec || ((ver > TPACKET_V2) &&
76 				(nl_type == PACKET_DIAG_TX_RING)))
77 		return 0;
78 
79 	pdr.pdr_block_size = ring->pg_vec_pages << PAGE_SHIFT;
80 	pdr.pdr_block_nr = ring->pg_vec_len;
81 	pdr.pdr_frame_size = ring->frame_size;
82 	pdr.pdr_frame_nr = ring->frame_max + 1;
83 
84 	if (ver > TPACKET_V2) {
85 		pdr.pdr_retire_tmo = ring->prb_bdqc.retire_blk_tov;
86 		pdr.pdr_sizeof_priv = ring->prb_bdqc.blk_sizeof_priv;
87 		pdr.pdr_features = ring->prb_bdqc.feature_req_word;
88 	} else {
89 		pdr.pdr_retire_tmo = 0;
90 		pdr.pdr_sizeof_priv = 0;
91 		pdr.pdr_features = 0;
92 	}
93 
94 	return nla_put(nlskb, nl_type, sizeof(pdr), &pdr);
95 }
96 
97 static int pdiag_put_rings_cfg(struct packet_sock *po, struct sk_buff *skb)
98 {
99 	int ret;
100 
101 	mutex_lock(&po->pg_vec_lock);
102 	ret = pdiag_put_ring(&po->rx_ring, po->tp_version,
103 			PACKET_DIAG_RX_RING, skb);
104 	if (!ret)
105 		ret = pdiag_put_ring(&po->tx_ring, po->tp_version,
106 				PACKET_DIAG_TX_RING, skb);
107 	mutex_unlock(&po->pg_vec_lock);
108 
109 	return ret;
110 }
111 
112 static int pdiag_put_fanout(struct packet_sock *po, struct sk_buff *nlskb)
113 {
114 	int ret = 0;
115 
116 	mutex_lock(&fanout_mutex);
117 	if (po->fanout) {
118 		u32 val;
119 
120 		val = (u32)po->fanout->id | ((u32)po->fanout->type << 16);
121 		ret = nla_put_u32(nlskb, PACKET_DIAG_FANOUT, val);
122 	}
123 	mutex_unlock(&fanout_mutex);
124 
125 	return ret;
126 }
127 
128 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct packet_diag_req *req,
129 		u32 portid, u32 seq, u32 flags, int sk_ino)
130 {
131 	struct nlmsghdr *nlh;
132 	struct packet_diag_msg *rp;
133 	struct packet_sock *po = pkt_sk(sk);
134 
135 	nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rp), flags);
136 	if (!nlh)
137 		return -EMSGSIZE;
138 
139 	rp = nlmsg_data(nlh);
140 	rp->pdiag_family = AF_PACKET;
141 	rp->pdiag_type = sk->sk_type;
142 	rp->pdiag_num = ntohs(po->num);
143 	rp->pdiag_ino = sk_ino;
144 	sock_diag_save_cookie(sk, rp->pdiag_cookie);
145 
146 	if ((req->pdiag_show & PACKET_SHOW_INFO) &&
147 			pdiag_put_info(po, skb))
148 		goto out_nlmsg_trim;
149 
150 	if ((req->pdiag_show & PACKET_SHOW_MCLIST) &&
151 			pdiag_put_mclist(po, skb))
152 		goto out_nlmsg_trim;
153 
154 	if ((req->pdiag_show & PACKET_SHOW_RING_CFG) &&
155 			pdiag_put_rings_cfg(po, skb))
156 		goto out_nlmsg_trim;
157 
158 	if ((req->pdiag_show & PACKET_SHOW_FANOUT) &&
159 			pdiag_put_fanout(po, skb))
160 		goto out_nlmsg_trim;
161 
162 	return nlmsg_end(skb, nlh);
163 
164 out_nlmsg_trim:
165 	nlmsg_cancel(skb, nlh);
166 	return -EMSGSIZE;
167 }
168 
169 static int packet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
170 {
171 	int num = 0, s_num = cb->args[0];
172 	struct packet_diag_req *req;
173 	struct net *net;
174 	struct sock *sk;
175 	struct hlist_node *node;
176 
177 	net = sock_net(skb->sk);
178 	req = nlmsg_data(cb->nlh);
179 
180 	mutex_lock(&net->packet.sklist_lock);
181 	sk_for_each(sk, node, &net->packet.sklist) {
182 		if (!net_eq(sock_net(sk), net))
183 			continue;
184 		if (num < s_num)
185 			goto next;
186 
187 		if (sk_diag_fill(sk, skb, req, NETLINK_CB(cb->skb).portid,
188 					cb->nlh->nlmsg_seq, NLM_F_MULTI,
189 					sock_i_ino(sk)) < 0)
190 			goto done;
191 next:
192 		num++;
193 	}
194 done:
195 	mutex_unlock(&net->packet.sklist_lock);
196 	cb->args[0] = num;
197 
198 	return skb->len;
199 }
200 
201 static int packet_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
202 {
203 	int hdrlen = sizeof(struct packet_diag_req);
204 	struct net *net = sock_net(skb->sk);
205 	struct packet_diag_req *req;
206 
207 	if (nlmsg_len(h) < hdrlen)
208 		return -EINVAL;
209 
210 	req = nlmsg_data(h);
211 	/* Make it possible to support protocol filtering later */
212 	if (req->sdiag_protocol)
213 		return -EINVAL;
214 
215 	if (h->nlmsg_flags & NLM_F_DUMP) {
216 		struct netlink_dump_control c = {
217 			.dump = packet_diag_dump,
218 		};
219 		return netlink_dump_start(net->diag_nlsk, skb, h, &c);
220 	} else
221 		return -EOPNOTSUPP;
222 }
223 
224 static const struct sock_diag_handler packet_diag_handler = {
225 	.family = AF_PACKET,
226 	.dump = packet_diag_handler_dump,
227 };
228 
229 static int __init packet_diag_init(void)
230 {
231 	return sock_diag_register(&packet_diag_handler);
232 }
233 
234 static void __exit packet_diag_exit(void)
235 {
236 	sock_diag_unregister(&packet_diag_handler);
237 }
238 
239 module_init(packet_diag_init);
240 module_exit(packet_diag_exit);
241 MODULE_LICENSE("GPL");
242 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 17 /* AF_PACKET */);
243