1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* SCTP kernel implementation
3  * Copyright (c) 2003 International Business Machines, Corp.
4  *
5  * This file is part of the SCTP kernel implementation
6  *
7  * Please send any bug reports or fixes you make to the
8  * email address(es):
9  *    lksctp developers <linux-sctp@vger.kernel.org>
10  *
11  * Written or modified by:
12  *    Sridhar Samudrala <sri@us.ibm.com>
13  */
14 
15 #include <linux/types.h>
16 #include <linux/seq_file.h>
17 #include <linux/init.h>
18 #include <linux/export.h>
19 #include <net/sctp/sctp.h>
20 #include <net/ip.h> /* for snmp_fold_field */
21 
22 static const struct snmp_mib sctp_snmp_list[] = {
23 	SNMP_MIB_ITEM("SctpCurrEstab", SCTP_MIB_CURRESTAB),
24 	SNMP_MIB_ITEM("SctpActiveEstabs", SCTP_MIB_ACTIVEESTABS),
25 	SNMP_MIB_ITEM("SctpPassiveEstabs", SCTP_MIB_PASSIVEESTABS),
26 	SNMP_MIB_ITEM("SctpAborteds", SCTP_MIB_ABORTEDS),
27 	SNMP_MIB_ITEM("SctpShutdowns", SCTP_MIB_SHUTDOWNS),
28 	SNMP_MIB_ITEM("SctpOutOfBlues", SCTP_MIB_OUTOFBLUES),
29 	SNMP_MIB_ITEM("SctpChecksumErrors", SCTP_MIB_CHECKSUMERRORS),
30 	SNMP_MIB_ITEM("SctpOutCtrlChunks", SCTP_MIB_OUTCTRLCHUNKS),
31 	SNMP_MIB_ITEM("SctpOutOrderChunks", SCTP_MIB_OUTORDERCHUNKS),
32 	SNMP_MIB_ITEM("SctpOutUnorderChunks", SCTP_MIB_OUTUNORDERCHUNKS),
33 	SNMP_MIB_ITEM("SctpInCtrlChunks", SCTP_MIB_INCTRLCHUNKS),
34 	SNMP_MIB_ITEM("SctpInOrderChunks", SCTP_MIB_INORDERCHUNKS),
35 	SNMP_MIB_ITEM("SctpInUnorderChunks", SCTP_MIB_INUNORDERCHUNKS),
36 	SNMP_MIB_ITEM("SctpFragUsrMsgs", SCTP_MIB_FRAGUSRMSGS),
37 	SNMP_MIB_ITEM("SctpReasmUsrMsgs", SCTP_MIB_REASMUSRMSGS),
38 	SNMP_MIB_ITEM("SctpOutSCTPPacks", SCTP_MIB_OUTSCTPPACKS),
39 	SNMP_MIB_ITEM("SctpInSCTPPacks", SCTP_MIB_INSCTPPACKS),
40 	SNMP_MIB_ITEM("SctpT1InitExpireds", SCTP_MIB_T1_INIT_EXPIREDS),
41 	SNMP_MIB_ITEM("SctpT1CookieExpireds", SCTP_MIB_T1_COOKIE_EXPIREDS),
42 	SNMP_MIB_ITEM("SctpT2ShutdownExpireds", SCTP_MIB_T2_SHUTDOWN_EXPIREDS),
43 	SNMP_MIB_ITEM("SctpT3RtxExpireds", SCTP_MIB_T3_RTX_EXPIREDS),
44 	SNMP_MIB_ITEM("SctpT4RtoExpireds", SCTP_MIB_T4_RTO_EXPIREDS),
45 	SNMP_MIB_ITEM("SctpT5ShutdownGuardExpireds", SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS),
46 	SNMP_MIB_ITEM("SctpDelaySackExpireds", SCTP_MIB_DELAY_SACK_EXPIREDS),
47 	SNMP_MIB_ITEM("SctpAutocloseExpireds", SCTP_MIB_AUTOCLOSE_EXPIREDS),
48 	SNMP_MIB_ITEM("SctpT3Retransmits", SCTP_MIB_T3_RETRANSMITS),
49 	SNMP_MIB_ITEM("SctpPmtudRetransmits", SCTP_MIB_PMTUD_RETRANSMITS),
50 	SNMP_MIB_ITEM("SctpFastRetransmits", SCTP_MIB_FAST_RETRANSMITS),
51 	SNMP_MIB_ITEM("SctpInPktSoftirq", SCTP_MIB_IN_PKT_SOFTIRQ),
52 	SNMP_MIB_ITEM("SctpInPktBacklog", SCTP_MIB_IN_PKT_BACKLOG),
53 	SNMP_MIB_ITEM("SctpInPktDiscards", SCTP_MIB_IN_PKT_DISCARDS),
54 	SNMP_MIB_ITEM("SctpInDataChunkDiscards", SCTP_MIB_IN_DATA_CHUNK_DISCARDS),
55 	SNMP_MIB_SENTINEL
56 };
57 
58 /* Display sctp snmp mib statistics(/proc/net/sctp/snmp). */
sctp_snmp_seq_show(struct seq_file * seq,void * v)59 static int sctp_snmp_seq_show(struct seq_file *seq, void *v)
60 {
61 	unsigned long buff[SCTP_MIB_MAX];
62 	struct net *net = seq->private;
63 	int i;
64 
65 	memset(buff, 0, sizeof(unsigned long) * SCTP_MIB_MAX);
66 
67 	snmp_get_cpu_field_batch(buff, sctp_snmp_list,
68 				 net->sctp.sctp_statistics);
69 	for (i = 0; sctp_snmp_list[i].name; i++)
70 		seq_printf(seq, "%-32s\t%ld\n", sctp_snmp_list[i].name,
71 						buff[i]);
72 
73 	return 0;
74 }
75 
76 /* Dump local addresses of an association/endpoint. */
sctp_seq_dump_local_addrs(struct seq_file * seq,struct sctp_ep_common * epb)77 static void sctp_seq_dump_local_addrs(struct seq_file *seq, struct sctp_ep_common *epb)
78 {
79 	struct sctp_association *asoc;
80 	struct sctp_sockaddr_entry *laddr;
81 	struct sctp_transport *peer;
82 	union sctp_addr *addr, *primary = NULL;
83 	struct sctp_af *af;
84 
85 	if (epb->type == SCTP_EP_TYPE_ASSOCIATION) {
86 		asoc = sctp_assoc(epb);
87 
88 		peer = asoc->peer.primary_path;
89 		if (unlikely(peer == NULL)) {
90 			WARN(1, "Association %p with NULL primary path!\n", asoc);
91 			return;
92 		}
93 
94 		primary = &peer->saddr;
95 	}
96 
97 	rcu_read_lock();
98 	list_for_each_entry_rcu(laddr, &epb->bind_addr.address_list, list) {
99 		if (!laddr->valid)
100 			continue;
101 
102 		addr = &laddr->a;
103 		af = sctp_get_af_specific(addr->sa.sa_family);
104 		if (primary && af->cmp_addr(addr, primary)) {
105 			seq_printf(seq, "*");
106 		}
107 		af->seq_dump_addr(seq, addr);
108 	}
109 	rcu_read_unlock();
110 }
111 
112 /* Dump remote addresses of an association. */
sctp_seq_dump_remote_addrs(struct seq_file * seq,struct sctp_association * assoc)113 static void sctp_seq_dump_remote_addrs(struct seq_file *seq, struct sctp_association *assoc)
114 {
115 	struct sctp_transport *transport;
116 	union sctp_addr *addr, *primary;
117 	struct sctp_af *af;
118 
119 	primary = &assoc->peer.primary_addr;
120 	list_for_each_entry_rcu(transport, &assoc->peer.transport_addr_list,
121 			transports) {
122 		addr = &transport->ipaddr;
123 
124 		af = sctp_get_af_specific(addr->sa.sa_family);
125 		if (af->cmp_addr(addr, primary)) {
126 			seq_printf(seq, "*");
127 		}
128 		af->seq_dump_addr(seq, addr);
129 	}
130 }
131 
sctp_eps_seq_start(struct seq_file * seq,loff_t * pos)132 static void *sctp_eps_seq_start(struct seq_file *seq, loff_t *pos)
133 {
134 	if (*pos >= sctp_ep_hashsize)
135 		return NULL;
136 
137 	if (*pos < 0)
138 		*pos = 0;
139 
140 	if (*pos == 0)
141 		seq_printf(seq, " ENDPT     SOCK   STY SST HBKT LPORT   UID INODE LADDRS\n");
142 
143 	return (void *)pos;
144 }
145 
sctp_eps_seq_stop(struct seq_file * seq,void * v)146 static void sctp_eps_seq_stop(struct seq_file *seq, void *v)
147 {
148 }
149 
150 
sctp_eps_seq_next(struct seq_file * seq,void * v,loff_t * pos)151 static void *sctp_eps_seq_next(struct seq_file *seq, void *v, loff_t *pos)
152 {
153 	if (++*pos >= sctp_ep_hashsize)
154 		return NULL;
155 
156 	return pos;
157 }
158 
159 
160 /* Display sctp endpoints (/proc/net/sctp/eps). */
sctp_eps_seq_show(struct seq_file * seq,void * v)161 static int sctp_eps_seq_show(struct seq_file *seq, void *v)
162 {
163 	struct sctp_hashbucket *head;
164 	struct sctp_ep_common *epb;
165 	struct sctp_endpoint *ep;
166 	struct sock *sk;
167 	int    hash = *(loff_t *)v;
168 
169 	if (hash >= sctp_ep_hashsize)
170 		return -ENOMEM;
171 
172 	head = &sctp_ep_hashtable[hash];
173 	read_lock_bh(&head->lock);
174 	sctp_for_each_hentry(epb, &head->chain) {
175 		ep = sctp_ep(epb);
176 		sk = epb->sk;
177 		if (!net_eq(sock_net(sk), seq_file_net(seq)))
178 			continue;
179 		seq_printf(seq, "%8pK %8pK %-3d %-3d %-4d %-5d %5u %5lu ", ep, sk,
180 			   sctp_sk(sk)->type, sk->sk_state, hash,
181 			   epb->bind_addr.port,
182 			   from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
183 			   sock_i_ino(sk));
184 
185 		sctp_seq_dump_local_addrs(seq, epb);
186 		seq_printf(seq, "\n");
187 	}
188 	read_unlock_bh(&head->lock);
189 
190 	return 0;
191 }
192 
193 static const struct seq_operations sctp_eps_ops = {
194 	.start = sctp_eps_seq_start,
195 	.next  = sctp_eps_seq_next,
196 	.stop  = sctp_eps_seq_stop,
197 	.show  = sctp_eps_seq_show,
198 };
199 
200 struct sctp_ht_iter {
201 	struct seq_net_private p;
202 	struct rhashtable_iter hti;
203 };
204 
sctp_transport_seq_start(struct seq_file * seq,loff_t * pos)205 static void *sctp_transport_seq_start(struct seq_file *seq, loff_t *pos)
206 {
207 	struct sctp_ht_iter *iter = seq->private;
208 
209 	sctp_transport_walk_start(&iter->hti);
210 
211 	return sctp_transport_get_idx(seq_file_net(seq), &iter->hti, *pos);
212 }
213 
sctp_transport_seq_stop(struct seq_file * seq,void * v)214 static void sctp_transport_seq_stop(struct seq_file *seq, void *v)
215 {
216 	struct sctp_ht_iter *iter = seq->private;
217 
218 	if (v && v != SEQ_START_TOKEN) {
219 		struct sctp_transport *transport = v;
220 
221 		sctp_transport_put(transport);
222 	}
223 
224 	sctp_transport_walk_stop(&iter->hti);
225 }
226 
sctp_transport_seq_next(struct seq_file * seq,void * v,loff_t * pos)227 static void *sctp_transport_seq_next(struct seq_file *seq, void *v, loff_t *pos)
228 {
229 	struct sctp_ht_iter *iter = seq->private;
230 
231 	if (v && v != SEQ_START_TOKEN) {
232 		struct sctp_transport *transport = v;
233 
234 		sctp_transport_put(transport);
235 	}
236 
237 	++*pos;
238 
239 	return sctp_transport_get_next(seq_file_net(seq), &iter->hti);
240 }
241 
242 /* Display sctp associations (/proc/net/sctp/assocs). */
sctp_assocs_seq_show(struct seq_file * seq,void * v)243 static int sctp_assocs_seq_show(struct seq_file *seq, void *v)
244 {
245 	struct sctp_transport *transport;
246 	struct sctp_association *assoc;
247 	struct sctp_ep_common *epb;
248 	struct sock *sk;
249 
250 	if (v == SEQ_START_TOKEN) {
251 		seq_printf(seq, " ASSOC     SOCK   STY SST ST HBKT "
252 				"ASSOC-ID TX_QUEUE RX_QUEUE UID INODE LPORT "
253 				"RPORT LADDRS <-> RADDRS "
254 				"HBINT INS OUTS MAXRT T1X T2X RTXC "
255 				"wmema wmemq sndbuf rcvbuf\n");
256 		return 0;
257 	}
258 
259 	transport = (struct sctp_transport *)v;
260 	assoc = transport->asoc;
261 	epb = &assoc->base;
262 	sk = epb->sk;
263 
264 	seq_printf(seq,
265 		   "%8pK %8pK %-3d %-3d %-2d %-4d "
266 		   "%4d %8d %8d %7u %5lu %-5d %5d ",
267 		   assoc, sk, sctp_sk(sk)->type, sk->sk_state,
268 		   assoc->state, 0,
269 		   assoc->assoc_id,
270 		   assoc->sndbuf_used,
271 		   atomic_read(&assoc->rmem_alloc),
272 		   from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
273 		   sock_i_ino(sk),
274 		   epb->bind_addr.port,
275 		   assoc->peer.port);
276 	seq_printf(seq, " ");
277 	sctp_seq_dump_local_addrs(seq, epb);
278 	seq_printf(seq, "<-> ");
279 	sctp_seq_dump_remote_addrs(seq, assoc);
280 	seq_printf(seq, "\t%8lu %5d %5d %4d %4d %4d %8d "
281 		   "%8d %8d %8d %8d",
282 		assoc->hbinterval, assoc->stream.incnt,
283 		assoc->stream.outcnt, assoc->max_retrans,
284 		assoc->init_retries, assoc->shutdown_retries,
285 		assoc->rtx_data_chunks,
286 		refcount_read(&sk->sk_wmem_alloc),
287 		sk->sk_wmem_queued,
288 		sk->sk_sndbuf,
289 		sk->sk_rcvbuf);
290 	seq_printf(seq, "\n");
291 
292 	return 0;
293 }
294 
295 static const struct seq_operations sctp_assoc_ops = {
296 	.start = sctp_transport_seq_start,
297 	.next  = sctp_transport_seq_next,
298 	.stop  = sctp_transport_seq_stop,
299 	.show  = sctp_assocs_seq_show,
300 };
301 
sctp_remaddr_seq_show(struct seq_file * seq,void * v)302 static int sctp_remaddr_seq_show(struct seq_file *seq, void *v)
303 {
304 	struct sctp_association *assoc;
305 	struct sctp_transport *transport, *tsp;
306 
307 	if (v == SEQ_START_TOKEN) {
308 		seq_printf(seq, "ADDR ASSOC_ID HB_ACT RTO MAX_PATH_RTX "
309 				"REM_ADDR_RTX START STATE\n");
310 		return 0;
311 	}
312 
313 	transport = (struct sctp_transport *)v;
314 	assoc = transport->asoc;
315 
316 	list_for_each_entry_rcu(tsp, &assoc->peer.transport_addr_list,
317 				transports) {
318 		/*
319 		 * The remote address (ADDR)
320 		 */
321 		tsp->af_specific->seq_dump_addr(seq, &tsp->ipaddr);
322 		seq_printf(seq, " ");
323 		/*
324 		 * The association ID (ASSOC_ID)
325 		 */
326 		seq_printf(seq, "%d ", tsp->asoc->assoc_id);
327 
328 		/*
329 		 * If the Heartbeat is active (HB_ACT)
330 		 * Note: 1 = Active, 0 = Inactive
331 		 */
332 		seq_printf(seq, "%d ", timer_pending(&tsp->hb_timer));
333 
334 		/*
335 		 * Retransmit time out (RTO)
336 		 */
337 		seq_printf(seq, "%lu ", tsp->rto);
338 
339 		/*
340 		 * Maximum path retransmit count (PATH_MAX_RTX)
341 		 */
342 		seq_printf(seq, "%d ", tsp->pathmaxrxt);
343 
344 		/*
345 		 * remote address retransmit count (REM_ADDR_RTX)
346 		 * Note: We don't have a way to tally this at the moment
347 		 * so lets just leave it as zero for the moment
348 		 */
349 		seq_puts(seq, "0 ");
350 
351 		/*
352 		 * remote address start time (START).  This is also not
353 		 * currently implemented, but we can record it with a
354 		 * jiffies marker in a subsequent patch
355 		 */
356 		seq_puts(seq, "0 ");
357 
358 		/*
359 		 * The current state of this destination. I.e.
360 		 * SCTP_ACTIVE, SCTP_INACTIVE, ...
361 		 */
362 		seq_printf(seq, "%d", tsp->state);
363 
364 		seq_printf(seq, "\n");
365 	}
366 
367 	return 0;
368 }
369 
370 static const struct seq_operations sctp_remaddr_ops = {
371 	.start = sctp_transport_seq_start,
372 	.next  = sctp_transport_seq_next,
373 	.stop  = sctp_transport_seq_stop,
374 	.show  = sctp_remaddr_seq_show,
375 };
376 
377 /* Set up the proc fs entry for the SCTP protocol. */
sctp_proc_init(struct net * net)378 int __net_init sctp_proc_init(struct net *net)
379 {
380 	net->sctp.proc_net_sctp = proc_net_mkdir(net, "sctp", net->proc_net);
381 	if (!net->sctp.proc_net_sctp)
382 		return -ENOMEM;
383 	if (!proc_create_net_single("snmp", 0444, net->sctp.proc_net_sctp,
384 			 sctp_snmp_seq_show, NULL))
385 		goto cleanup;
386 	if (!proc_create_net("eps", 0444, net->sctp.proc_net_sctp,
387 			&sctp_eps_ops, sizeof(struct seq_net_private)))
388 		goto cleanup;
389 	if (!proc_create_net("assocs", 0444, net->sctp.proc_net_sctp,
390 			&sctp_assoc_ops, sizeof(struct sctp_ht_iter)))
391 		goto cleanup;
392 	if (!proc_create_net("remaddr", 0444, net->sctp.proc_net_sctp,
393 			&sctp_remaddr_ops, sizeof(struct sctp_ht_iter)))
394 		goto cleanup;
395 	return 0;
396 
397 cleanup:
398 	remove_proc_subtree("sctp", net->proc_net);
399 	net->sctp.proc_net_sctp = NULL;
400 	return -ENOMEM;
401 }
402