1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2019 Isilon Systems, LLC.
5 * Copyright (c) 2005-2014 Sandvine Incorporated. All rights reserved.
6 * Copyright (c) 2000 Darrell Anderson
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <sys/cdefs.h>
32 #include "opt_ddb.h"
33 #include "opt_inet.h"
34
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/endian.h>
38 #include <sys/errno.h>
39 #include <sys/eventhandler.h>
40 #include <sys/kernel.h>
41 #include <sys/lock.h>
42 #include <sys/mutex.h>
43 #include <sys/socket.h>
44 #include <sys/sysctl.h>
45
46 #ifdef DDB
47 #include <ddb/ddb.h>
48 #include <ddb/db_lex.h>
49 #endif
50
51 #include <net/ethernet.h>
52 #include <net/if.h>
53 #include <net/if_arp.h>
54 #include <net/if_dl.h>
55 #include <net/if_types.h>
56 #include <net/if_var.h>
57 #include <net/if_private.h>
58 #include <net/vnet.h>
59 #include <net/route.h>
60 #include <net/route/nhop.h>
61
62 #include <netinet/in.h>
63 #include <netinet/in_fib.h>
64 #include <netinet/in_systm.h>
65 #include <netinet/in_var.h>
66 #include <netinet/ip.h>
67 #include <netinet/ip_var.h>
68 #include <netinet/ip_options.h>
69 #include <netinet/udp.h>
70 #include <netinet/udp_var.h>
71
72 #include <machine/in_cksum.h>
73 #include <machine/pcb.h>
74
75 #include <net/debugnet.h>
76 #define DEBUGNET_INTERNAL
77 #include <net/debugnet_int.h>
78
79 FEATURE(debugnet, "Debugnet support");
80
81 SYSCTL_NODE(_net, OID_AUTO, debugnet, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
82 "debugnet parameters");
83
84 unsigned debugnet_debug;
85 SYSCTL_UINT(_net_debugnet, OID_AUTO, debug, CTLFLAG_RWTUN,
86 &debugnet_debug, 0,
87 "Debug message verbosity (0: off; 1: on; 2: verbose)");
88
89 int debugnet_npolls = 2000;
90 SYSCTL_INT(_net_debugnet, OID_AUTO, npolls, CTLFLAG_RWTUN,
91 &debugnet_npolls, 0,
92 "Number of times to poll before assuming packet loss (0.5ms per poll)");
93 int debugnet_nretries = 10;
94 SYSCTL_INT(_net_debugnet, OID_AUTO, nretries, CTLFLAG_RWTUN,
95 &debugnet_nretries, 0,
96 "Number of retransmit attempts before giving up");
97 int debugnet_fib = RT_DEFAULT_FIB;
98 SYSCTL_INT(_net_debugnet, OID_AUTO, fib, CTLFLAG_RWTUN,
99 &debugnet_fib, 0,
100 "Fib to use when sending dump");
101
102 static bool g_debugnet_pcb_inuse;
103 static struct debugnet_pcb g_dnet_pcb;
104
105 /*
106 * Simple accessors for opaque PCB.
107 */
108 const unsigned char *
debugnet_get_gw_mac(const struct debugnet_pcb * pcb)109 debugnet_get_gw_mac(const struct debugnet_pcb *pcb)
110 {
111 MPASS(g_debugnet_pcb_inuse && pcb == &g_dnet_pcb &&
112 pcb->dp_state >= DN_STATE_HAVE_GW_MAC);
113 return (pcb->dp_gw_mac.octet);
114 }
115
116 const in_addr_t *
debugnet_get_server_addr(const struct debugnet_pcb * pcb)117 debugnet_get_server_addr(const struct debugnet_pcb *pcb)
118 {
119 MPASS(g_debugnet_pcb_inuse && pcb == &g_dnet_pcb &&
120 pcb->dp_state >= DN_STATE_GOT_HERALD_PORT);
121 return (&pcb->dp_server);
122 }
123
124 const uint16_t
debugnet_get_server_port(const struct debugnet_pcb * pcb)125 debugnet_get_server_port(const struct debugnet_pcb *pcb)
126 {
127 MPASS(g_debugnet_pcb_inuse && pcb == &g_dnet_pcb &&
128 pcb->dp_state >= DN_STATE_GOT_HERALD_PORT);
129 return (pcb->dp_server_port);
130 }
131
132 /*
133 * Start of network primitives, beginning with output primitives.
134 */
135
136 /*
137 * Handles creation of the ethernet header, then places outgoing packets into
138 * the tx buffer for the NIC
139 *
140 * Parameters:
141 * m The mbuf containing the packet to be sent (will be freed by
142 * this function or the NIC driver)
143 * ifp The interface to send on
144 * dst The destination ethernet address (source address will be looked
145 * up using ifp)
146 * etype The ETHERTYPE_* value for the protocol that is being sent
147 *
148 * Returns:
149 * int see errno.h, 0 for success
150 */
151 int
debugnet_ether_output(struct mbuf * m,struct ifnet * ifp,struct ether_addr dst,u_short etype)152 debugnet_ether_output(struct mbuf *m, struct ifnet *ifp, struct ether_addr dst,
153 u_short etype)
154 {
155 struct ether_header *eh;
156
157 if (((ifp->if_flags & (IFF_MONITOR | IFF_UP)) != IFF_UP) ||
158 (ifp->if_drv_flags & IFF_DRV_RUNNING) != IFF_DRV_RUNNING) {
159 if_printf(ifp, "%s: interface isn't up\n", __func__);
160 m_freem(m);
161 return (ENETDOWN);
162 }
163
164 /* Fill in the ethernet header. */
165 M_PREPEND(m, ETHER_HDR_LEN, M_NOWAIT);
166 if (m == NULL) {
167 printf("%s: out of mbufs\n", __func__);
168 return (ENOBUFS);
169 }
170 eh = mtod(m, struct ether_header *);
171 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN);
172 memcpy(eh->ether_dhost, dst.octet, ETHER_ADDR_LEN);
173 eh->ether_type = htons(etype);
174 return (ifp->if_debugnet_methods->dn_transmit(ifp, m));
175 }
176
177 /*
178 * Unreliable transmission of an mbuf chain to the debugnet server
179 * Note: can't handle fragmentation; fails if the packet is larger than
180 * ifp->if_mtu after adding the UDP/IP headers
181 *
182 * Parameters:
183 * pcb The debugnet context block
184 * m mbuf chain
185 *
186 * Returns:
187 * int see errno.h, 0 for success
188 */
189 static int
debugnet_udp_output(struct debugnet_pcb * pcb,struct mbuf * m)190 debugnet_udp_output(struct debugnet_pcb *pcb, struct mbuf *m)
191 {
192 struct udphdr *udp;
193
194 MPASS(pcb->dp_state >= DN_STATE_HAVE_GW_MAC);
195
196 M_PREPEND(m, sizeof(*udp), M_NOWAIT);
197 if (m == NULL) {
198 printf("%s: out of mbufs\n", __func__);
199 return (ENOBUFS);
200 }
201
202 udp = mtod(m, struct udphdr *);
203 udp->uh_ulen = htons(m->m_pkthdr.len);
204 /* Use this src port so that the server can connect() the socket */
205 udp->uh_sport = htons(pcb->dp_client_port);
206 udp->uh_dport = htons(pcb->dp_server_port);
207 /* Computed later (protocol-dependent). */
208 udp->uh_sum = 0;
209
210 return (debugnet_ip_output(pcb, m));
211 }
212
213 int
debugnet_ack_output(struct debugnet_pcb * pcb,uint32_t seqno)214 debugnet_ack_output(struct debugnet_pcb *pcb, uint32_t seqno /* net endian */)
215 {
216 struct debugnet_ack *dn_ack;
217 struct mbuf *m;
218
219 DNETDEBUG("Acking with seqno %u\n", ntohl(seqno));
220
221 m = m_gethdr(M_NOWAIT, MT_DATA);
222 if (m == NULL) {
223 printf("%s: Out of mbufs\n", __func__);
224 return (ENOBUFS);
225 }
226 m->m_len = sizeof(*dn_ack);
227 m->m_pkthdr.len = sizeof(*dn_ack);
228 MH_ALIGN(m, sizeof(*dn_ack));
229 dn_ack = mtod(m, struct debugnet_ack *);
230 dn_ack->da_seqno = seqno;
231
232 return (debugnet_udp_output(pcb, m));
233 }
234
235 /*
236 * Dummy free function for debugnet clusters.
237 */
238 static void
debugnet_mbuf_free(struct mbuf * m __unused)239 debugnet_mbuf_free(struct mbuf *m __unused)
240 {
241 }
242
243 /*
244 * Construct and reliably send a debugnet packet. May fail from a resource
245 * shortage or extreme number of unacknowledged retransmissions. Wait for
246 * an acknowledgement before returning. Splits packets into chunks small
247 * enough to be sent without fragmentation (looks up the interface MTU)
248 *
249 * Parameters:
250 * type debugnet packet type (HERALD, FINISHED, ...)
251 * data data
252 * datalen data size (bytes)
253 * auxdata optional auxiliary information
254 *
255 * Returns:
256 * int see errno.h, 0 for success
257 */
258 int
debugnet_send(struct debugnet_pcb * pcb,uint32_t type,const void * data,uint32_t datalen,const struct debugnet_proto_aux * auxdata)259 debugnet_send(struct debugnet_pcb *pcb, uint32_t type, const void *data,
260 uint32_t datalen, const struct debugnet_proto_aux *auxdata)
261 {
262 struct debugnet_msg_hdr *dn_msg_hdr;
263 struct mbuf *m, *m2;
264 uint64_t want_acks;
265 uint32_t i, pktlen, sent_so_far;
266 int retries, polls, error;
267
268 if (pcb->dp_state == DN_STATE_REMOTE_CLOSED)
269 return (ECONNRESET);
270
271 want_acks = 0;
272 pcb->dp_rcvd_acks = 0;
273 retries = 0;
274
275 retransmit:
276 /* Chunks can be too big to fit in packets. */
277 for (i = sent_so_far = 0; sent_so_far < datalen ||
278 (i == 0 && datalen == 0); i++) {
279 pktlen = datalen - sent_so_far;
280
281 /* Bound: the interface MTU (assume no IP options). */
282 pktlen = min(pktlen, pcb->dp_ifp->if_mtu -
283 sizeof(struct udpiphdr) - sizeof(struct debugnet_msg_hdr));
284
285 /*
286 * Check if it is retransmitting and this has been ACKed
287 * already.
288 */
289 if ((pcb->dp_rcvd_acks & (1 << i)) != 0) {
290 sent_so_far += pktlen;
291 continue;
292 }
293
294 /*
295 * Get and fill a header mbuf, then chain data as an extended
296 * mbuf.
297 */
298 m = m_gethdr(M_NOWAIT, MT_DATA);
299 if (m == NULL) {
300 printf("%s: Out of mbufs\n", __func__);
301 return (ENOBUFS);
302 }
303 m->m_len = sizeof(struct debugnet_msg_hdr);
304 m->m_pkthdr.len = sizeof(struct debugnet_msg_hdr);
305 MH_ALIGN(m, sizeof(struct debugnet_msg_hdr));
306 dn_msg_hdr = mtod(m, struct debugnet_msg_hdr *);
307 dn_msg_hdr->mh_seqno = htonl(pcb->dp_seqno + i);
308 dn_msg_hdr->mh_type = htonl(type);
309 dn_msg_hdr->mh_len = htonl(pktlen);
310
311 if (auxdata != NULL) {
312 dn_msg_hdr->mh_offset =
313 htobe64(auxdata->dp_offset_start + sent_so_far);
314 dn_msg_hdr->mh_aux2 = htobe32(auxdata->dp_aux2);
315 } else {
316 dn_msg_hdr->mh_offset = htobe64(sent_so_far);
317 dn_msg_hdr->mh_aux2 = 0;
318 }
319
320 if (pktlen != 0) {
321 m2 = m_get(M_NOWAIT, MT_DATA);
322 if (m2 == NULL) {
323 m_freem(m);
324 printf("%s: Out of mbufs\n", __func__);
325 return (ENOBUFS);
326 }
327 MEXTADD(m2, __DECONST(char *, data) + sent_so_far,
328 pktlen, debugnet_mbuf_free, NULL, NULL, 0,
329 EXT_DISPOSABLE);
330 m2->m_len = pktlen;
331
332 m_cat(m, m2);
333 m->m_pkthdr.len += pktlen;
334 }
335 error = debugnet_udp_output(pcb, m);
336 if (error != 0)
337 return (error);
338
339 /* Note that we're waiting for this packet in the bitfield. */
340 want_acks |= (1 << i);
341 sent_so_far += pktlen;
342 }
343 if (i >= DEBUGNET_MAX_IN_FLIGHT)
344 printf("Warning: Sent more than %d packets (%d). "
345 "Acknowledgements will fail unless the size of "
346 "rcvd_acks/want_acks is increased.\n",
347 DEBUGNET_MAX_IN_FLIGHT, i);
348
349 /*
350 * Wait for acks. A *real* window would speed things up considerably.
351 */
352 polls = 0;
353 while (pcb->dp_rcvd_acks != want_acks) {
354 if (polls++ > debugnet_npolls) {
355 if (retries++ > debugnet_nretries)
356 return (ETIMEDOUT);
357 printf(". ");
358 goto retransmit;
359 }
360 debugnet_network_poll(pcb);
361 DELAY(500);
362 if (pcb->dp_state == DN_STATE_REMOTE_CLOSED)
363 return (ECONNRESET);
364 }
365 pcb->dp_seqno += i;
366 return (0);
367 }
368
369 /*
370 * Network input primitives.
371 */
372
373 /*
374 * Just introspect the header enough to fire off a seqno ack and validate
375 * length fits.
376 */
377 static void
debugnet_handle_rx_msg(struct debugnet_pcb * pcb,struct mbuf ** mb)378 debugnet_handle_rx_msg(struct debugnet_pcb *pcb, struct mbuf **mb)
379 {
380 const struct debugnet_msg_hdr *dnh;
381 struct mbuf *m;
382 uint32_t hdr_type;
383 uint32_t seqno;
384 int error;
385
386 m = *mb;
387
388 if (m->m_pkthdr.len < sizeof(*dnh)) {
389 DNETDEBUG("ignoring small debugnet_msg packet\n");
390 return;
391 }
392
393 /* Get ND header. */
394 if (m->m_len < sizeof(*dnh)) {
395 m = m_pullup(m, sizeof(*dnh));
396 *mb = m;
397 if (m == NULL) {
398 DNETDEBUG("m_pullup failed\n");
399 return;
400 }
401 }
402
403 dnh = mtod(m, const struct debugnet_msg_hdr *);
404 if (ntohl(dnh->mh_len) + sizeof(*dnh) > m->m_pkthdr.len) {
405 DNETDEBUG("Dropping short packet.\n");
406 return;
407 }
408
409 hdr_type = ntohl(dnh->mh_type);
410 if (hdr_type != DEBUGNET_DATA) {
411 if (hdr_type == DEBUGNET_FINISHED) {
412 printf("Remote shut down the connection on us!\n");
413 pcb->dp_state = DN_STATE_REMOTE_CLOSED;
414 if (pcb->dp_finish_handler != NULL) {
415 pcb->dp_finish_handler();
416 }
417 } else {
418 DNETDEBUG("Got unexpected debugnet message %u\n", hdr_type);
419 }
420 return;
421 }
422
423 /*
424 * If the issue is transient (ENOBUFS), sender should resend. If
425 * non-transient (like driver objecting to rx -> tx from the same
426 * thread), not much else we can do.
427 */
428 seqno = dnh->mh_seqno; /* net endian */
429 m_adj(m, sizeof(*dnh));
430 dnh = NULL;
431 error = pcb->dp_rx_handler(m);
432 if (error != 0) {
433 DNETDEBUG("RX handler was not able to accept message, error %d. "
434 "Skipping ack.\n", error);
435 return;
436 }
437
438 error = debugnet_ack_output(pcb, seqno);
439 if (error != 0) {
440 DNETDEBUG("Couldn't ACK rx packet %u; %d\n", ntohl(seqno), error);
441 }
442 }
443
444 static void
debugnet_handle_ack(struct debugnet_pcb * pcb,struct mbuf ** mb,uint16_t sport)445 debugnet_handle_ack(struct debugnet_pcb *pcb, struct mbuf **mb, uint16_t sport)
446 {
447 const struct debugnet_ack *dn_ack;
448 struct mbuf *m;
449 uint32_t rcv_ackno;
450
451 m = *mb;
452
453 /* Get Ack. */
454 if (m->m_len < sizeof(*dn_ack)) {
455 m = m_pullup(m, sizeof(*dn_ack));
456 *mb = m;
457 if (m == NULL) {
458 DNETDEBUG("m_pullup failed\n");
459 return;
460 }
461 }
462 dn_ack = mtod(m, const struct debugnet_ack *);
463
464 /* Debugnet processing. */
465 /*
466 * Packet is meant for us. Extract the ack sequence number and the
467 * port number if necessary.
468 */
469 rcv_ackno = ntohl(dn_ack->da_seqno);
470 if (pcb->dp_state < DN_STATE_GOT_HERALD_PORT) {
471 pcb->dp_server_port = sport;
472 pcb->dp_state = DN_STATE_GOT_HERALD_PORT;
473 }
474 if (rcv_ackno >= pcb->dp_seqno + DEBUGNET_MAX_IN_FLIGHT)
475 printf("%s: ACK %u too far in future!\n", __func__, rcv_ackno);
476 else if (rcv_ackno >= pcb->dp_seqno) {
477 /* We're interested in this ack. Record it. */
478 pcb->dp_rcvd_acks |= 1 << (rcv_ackno - pcb->dp_seqno);
479 }
480 }
481
482 void
debugnet_handle_udp(struct debugnet_pcb * pcb,struct mbuf ** mb)483 debugnet_handle_udp(struct debugnet_pcb *pcb, struct mbuf **mb)
484 {
485 const struct udphdr *udp;
486 struct mbuf *m;
487 uint16_t sport, ulen;
488
489 /* UDP processing. */
490
491 m = *mb;
492 if (m->m_pkthdr.len < sizeof(*udp)) {
493 DNETDEBUG("ignoring small UDP packet\n");
494 return;
495 }
496
497 /* Get UDP headers. */
498 if (m->m_len < sizeof(*udp)) {
499 m = m_pullup(m, sizeof(*udp));
500 *mb = m;
501 if (m == NULL) {
502 DNETDEBUG("m_pullup failed\n");
503 return;
504 }
505 }
506 udp = mtod(m, const struct udphdr *);
507
508 /* We expect to receive UDP packets on the configured client port. */
509 if (ntohs(udp->uh_dport) != pcb->dp_client_port) {
510 DNETDEBUG("not on the expected port.\n");
511 return;
512 }
513
514 /* Check that ulen does not exceed actual size of data. */
515 ulen = ntohs(udp->uh_ulen);
516 if (m->m_pkthdr.len < ulen) {
517 DNETDEBUG("ignoring runt UDP packet\n");
518 return;
519 }
520
521 sport = ntohs(udp->uh_sport);
522
523 m_adj(m, sizeof(*udp));
524 ulen -= sizeof(*udp);
525
526 if (ulen == sizeof(struct debugnet_ack)) {
527 debugnet_handle_ack(pcb, mb, sport);
528 return;
529 }
530
531 if (pcb->dp_rx_handler == NULL) {
532 if (ulen < sizeof(struct debugnet_ack))
533 DNETDEBUG("ignoring small ACK packet\n");
534 else
535 DNETDEBUG("ignoring unexpected non-ACK packet on "
536 "half-duplex connection.\n");
537 return;
538 }
539
540 debugnet_handle_rx_msg(pcb, mb);
541 }
542
543 /*
544 * Handler for incoming packets directly from the network adapter
545 * Identifies the packet type (IP or ARP) and passes it along to one of the
546 * helper functions debugnet_handle_ip or debugnet_handle_arp.
547 *
548 * It needs to partially replicate the behaviour of ether_input() and
549 * ether_demux().
550 *
551 * Parameters:
552 * ifp the interface the packet came from
553 * m an mbuf containing the packet received
554 */
555 static void
debugnet_input_one(struct ifnet * ifp,struct mbuf * m)556 debugnet_input_one(struct ifnet *ifp, struct mbuf *m)
557 {
558 struct ifreq ifr;
559 struct ether_header *eh;
560 u_short etype;
561
562 /* Ethernet processing. */
563 if ((m->m_flags & M_PKTHDR) == 0) {
564 DNETDEBUG_IF(ifp, "discard frame without packet header\n");
565 goto done;
566 }
567 if (m->m_len < ETHER_HDR_LEN) {
568 DNETDEBUG_IF(ifp,
569 "discard frame without leading eth header (len %d pktlen %d)\n",
570 m->m_len, m->m_pkthdr.len);
571 goto done;
572 }
573 eh = mtod(m, struct ether_header *);
574 etype = ntohs(eh->ether_type);
575 if ((m->m_flags & M_VLANTAG) != 0 || etype == ETHERTYPE_VLAN) {
576 DNETDEBUG_IF(ifp, "ignoring vlan packets\n");
577 goto done;
578 }
579 if (if_gethwaddr(ifp, &ifr) != 0) {
580 DNETDEBUG_IF(ifp, "failed to get hw addr for interface\n");
581 goto done;
582 }
583 if (memcmp(ifr.ifr_addr.sa_data, eh->ether_dhost,
584 ETHER_ADDR_LEN) != 0 &&
585 (etype != ETHERTYPE_ARP || !ETHER_IS_BROADCAST(eh->ether_dhost))) {
586 DNETDEBUG_IF(ifp,
587 "discard frame with incorrect destination addr\n");
588 goto done;
589 }
590
591 MPASS(g_debugnet_pcb_inuse);
592
593 /* Done ethernet processing. Strip off the ethernet header. */
594 m_adj(m, ETHER_HDR_LEN);
595 switch (etype) {
596 case ETHERTYPE_ARP:
597 debugnet_handle_arp(&g_dnet_pcb, &m);
598 break;
599 case ETHERTYPE_IP:
600 debugnet_handle_ip(&g_dnet_pcb, &m);
601 break;
602 default:
603 DNETDEBUG_IF(ifp, "dropping unknown ethertype %hu\n", etype);
604 break;
605 }
606 done:
607 if (m != NULL)
608 m_freem(m);
609 }
610
611 static void
debugnet_input(struct ifnet * ifp,struct mbuf * m)612 debugnet_input(struct ifnet *ifp, struct mbuf *m)
613 {
614 struct mbuf *n;
615
616 do {
617 n = m->m_nextpkt;
618 m->m_nextpkt = NULL;
619 debugnet_input_one(ifp, m);
620 m = n;
621 } while (m != NULL);
622 }
623
624 /*
625 * Network polling primitive.
626 *
627 * Instead of assuming that most of the network stack is sane, we just poll the
628 * driver directly for packets.
629 */
630 void
debugnet_network_poll(struct debugnet_pcb * pcb)631 debugnet_network_poll(struct debugnet_pcb *pcb)
632 {
633 struct ifnet *ifp;
634
635 ifp = pcb->dp_ifp;
636 ifp->if_debugnet_methods->dn_poll(ifp, 1000);
637 }
638
639 /*
640 * Start of consumer API surface.
641 */
642 void
debugnet_free(struct debugnet_pcb * pcb)643 debugnet_free(struct debugnet_pcb *pcb)
644 {
645 struct ifnet *ifp;
646
647 MPASS(pcb == &g_dnet_pcb);
648 MPASS(pcb->dp_drv_input == NULL || g_debugnet_pcb_inuse);
649
650 ifp = pcb->dp_ifp;
651 if (ifp != NULL) {
652 if (pcb->dp_drv_input != NULL)
653 ifp->if_input = pcb->dp_drv_input;
654 if (pcb->dp_event_started)
655 ifp->if_debugnet_methods->dn_event(ifp, DEBUGNET_END);
656 }
657 debugnet_mbuf_finish();
658
659 g_debugnet_pcb_inuse = false;
660 memset(&g_dnet_pcb, 0xfd, sizeof(g_dnet_pcb));
661 }
662
663 int
debugnet_connect(const struct debugnet_conn_params * dcp,struct debugnet_pcb ** pcb_out)664 debugnet_connect(const struct debugnet_conn_params *dcp,
665 struct debugnet_pcb **pcb_out)
666 {
667 struct debugnet_proto_aux herald_auxdata;
668 struct debugnet_pcb *pcb;
669 struct ifnet *ifp;
670 int error;
671
672 if (g_debugnet_pcb_inuse) {
673 printf("%s: Only one connection at a time.\n", __func__);
674 return (EBUSY);
675 }
676
677 pcb = &g_dnet_pcb;
678 *pcb = (struct debugnet_pcb) {
679 .dp_state = DN_STATE_INIT,
680 .dp_client = dcp->dc_client,
681 .dp_server = dcp->dc_server,
682 .dp_gateway = dcp->dc_gateway,
683 .dp_server_port = dcp->dc_herald_port, /* Initially */
684 .dp_client_port = dcp->dc_client_port,
685 .dp_seqno = 1,
686 .dp_ifp = dcp->dc_ifp,
687 .dp_rx_handler = dcp->dc_rx_handler,
688 .dp_drv_input = NULL,
689 };
690
691 /* Switch to the debugnet mbuf zones. */
692 debugnet_mbuf_start();
693
694 /* At least one needed parameter is missing; infer it. */
695 if (pcb->dp_client == INADDR_ANY || pcb->dp_gateway == INADDR_ANY ||
696 pcb->dp_ifp == NULL) {
697 struct sockaddr_in dest_sin, *gw_sin, *local_sin;
698 struct ifnet *rt_ifp;
699 struct nhop_object *nh;
700
701 memset(&dest_sin, 0, sizeof(dest_sin));
702 dest_sin = (struct sockaddr_in) {
703 .sin_len = sizeof(dest_sin),
704 .sin_family = AF_INET,
705 .sin_addr.s_addr = pcb->dp_server,
706 };
707
708 CURVNET_SET(vnet0);
709 nh = fib4_lookup_debugnet(debugnet_fib, dest_sin.sin_addr, 0,
710 NHR_NONE);
711 CURVNET_RESTORE();
712
713 if (nh == NULL) {
714 printf("%s: Could not get route for that server.\n",
715 __func__);
716 error = ENOENT;
717 goto cleanup;
718 }
719
720 /* TODO support AF_INET6 */
721 if (nh->gw_sa.sa_family == AF_INET)
722 gw_sin = &nh->gw4_sa;
723 else {
724 if (nh->gw_sa.sa_family == AF_LINK)
725 DNETDEBUG("Destination address is on link.\n");
726 gw_sin = NULL;
727 }
728
729 MPASS(nh->nh_ifa->ifa_addr->sa_family == AF_INET);
730 local_sin = (struct sockaddr_in *)nh->nh_ifa->ifa_addr;
731
732 rt_ifp = nh->nh_ifp;
733
734 if (pcb->dp_client == INADDR_ANY)
735 pcb->dp_client = local_sin->sin_addr.s_addr;
736 if (pcb->dp_gateway == INADDR_ANY && gw_sin != NULL)
737 pcb->dp_gateway = gw_sin->sin_addr.s_addr;
738 if (pcb->dp_ifp == NULL)
739 pcb->dp_ifp = rt_ifp;
740 }
741
742 ifp = pcb->dp_ifp;
743
744 if (debugnet_debug > 0) {
745 char serbuf[INET_ADDRSTRLEN], clibuf[INET_ADDRSTRLEN],
746 gwbuf[INET_ADDRSTRLEN];
747 inet_ntop(AF_INET, &pcb->dp_server, serbuf, sizeof(serbuf));
748 inet_ntop(AF_INET, &pcb->dp_client, clibuf, sizeof(clibuf));
749 if (pcb->dp_gateway != INADDR_ANY)
750 inet_ntop(AF_INET, &pcb->dp_gateway, gwbuf, sizeof(gwbuf));
751 DNETDEBUG("Connecting to %s:%d%s%s from %s:%d on %s\n",
752 serbuf, pcb->dp_server_port,
753 (pcb->dp_gateway == INADDR_ANY) ? "" : " via ",
754 (pcb->dp_gateway == INADDR_ANY) ? "" : gwbuf,
755 clibuf, pcb->dp_client_port, if_name(ifp));
756 }
757
758 /* Validate iface is online and supported. */
759 if (!DEBUGNET_SUPPORTED_NIC(ifp)) {
760 printf("%s: interface '%s' does not support debugnet\n",
761 __func__, if_name(ifp));
762 error = ENODEV;
763 goto cleanup;
764 }
765 if ((if_getflags(ifp) & IFF_UP) == 0) {
766 printf("%s: interface '%s' link is down\n", __func__,
767 if_name(ifp));
768 error = ENXIO;
769 goto cleanup;
770 }
771
772 ifp->if_debugnet_methods->dn_event(ifp, DEBUGNET_START);
773 pcb->dp_event_started = true;
774
775 /*
776 * We maintain the invariant that g_debugnet_pcb_inuse is always true
777 * while the debugnet ifp's if_input is overridden with
778 * debugnet_input().
779 */
780 g_debugnet_pcb_inuse = true;
781
782 /* Make the card use *our* receive callback. */
783 pcb->dp_drv_input = ifp->if_input;
784 ifp->if_input = debugnet_input;
785
786 printf("%s: searching for %s MAC...\n", __func__,
787 (dcp->dc_gateway == INADDR_ANY) ? "server" : "gateway");
788
789 error = debugnet_arp_gw(pcb);
790 if (error != 0) {
791 printf("%s: failed to locate MAC address\n", __func__);
792 goto cleanup;
793 }
794 MPASS(pcb->dp_state == DN_STATE_HAVE_GW_MAC);
795
796 herald_auxdata = (struct debugnet_proto_aux) {
797 .dp_offset_start = dcp->dc_herald_offset,
798 .dp_aux2 = dcp->dc_herald_aux2,
799 };
800 error = debugnet_send(pcb, DEBUGNET_HERALD, dcp->dc_herald_data,
801 dcp->dc_herald_datalen, &herald_auxdata);
802 if (error != 0) {
803 printf("%s: failed to herald debugnet server\n", __func__);
804 goto cleanup;
805 }
806
807 *pcb_out = pcb;
808 return (0);
809
810 cleanup:
811 debugnet_free(pcb);
812 return (error);
813 }
814
815 /*
816 * Pre-allocated dump-time mbuf tracking.
817 *
818 * We just track the high water mark we've ever seen and allocate appropriately
819 * for that iface/mtu combo.
820 */
821 static struct {
822 int nmbuf;
823 int ncl;
824 int clsize;
825 } dn_hwm;
826 static struct mtx dn_hwm_lk;
827 MTX_SYSINIT(debugnet_hwm_lock, &dn_hwm_lk, "Debugnet HWM lock", MTX_DEF);
828
829 static void
dn_maybe_reinit_mbufs(int nmbuf,int ncl,int clsize)830 dn_maybe_reinit_mbufs(int nmbuf, int ncl, int clsize)
831 {
832 bool any;
833
834 any = false;
835 mtx_lock(&dn_hwm_lk);
836
837 if (nmbuf > dn_hwm.nmbuf) {
838 any = true;
839 dn_hwm.nmbuf = nmbuf;
840 } else
841 nmbuf = dn_hwm.nmbuf;
842
843 if (ncl > dn_hwm.ncl) {
844 any = true;
845 dn_hwm.ncl = ncl;
846 } else
847 ncl = dn_hwm.ncl;
848
849 if (clsize > dn_hwm.clsize) {
850 any = true;
851 dn_hwm.clsize = clsize;
852 } else
853 clsize = dn_hwm.clsize;
854
855 mtx_unlock(&dn_hwm_lk);
856
857 if (any)
858 debugnet_mbuf_reinit(nmbuf, ncl, clsize);
859 }
860
861 void
debugnet_any_ifnet_update(struct ifnet * ifp)862 debugnet_any_ifnet_update(struct ifnet *ifp)
863 {
864 int clsize, nmbuf, ncl, nrxr;
865
866 if (!DEBUGNET_SUPPORTED_NIC(ifp))
867 return;
868
869 ifp->if_debugnet_methods->dn_init(ifp, &nrxr, &ncl, &clsize);
870 KASSERT(nrxr > 0, ("invalid receive ring count %d", nrxr));
871
872 /*
873 * We need two headers per message on the transmit side. Multiply by
874 * four to give us some breathing room.
875 */
876 nmbuf = ncl * (4 + nrxr);
877 ncl *= nrxr;
878
879 /*
880 * Bandaid for drivers that (incorrectly) advertise LinkUp before their
881 * dn_init method is available.
882 */
883 if (nmbuf == 0 || ncl == 0 || clsize == 0) {
884 #ifndef INVARIANTS
885 if (bootverbose)
886 #endif
887 printf("%s: Bad dn_init result from %s (ifp %p), ignoring.\n",
888 __func__, if_name(ifp), ifp);
889 return;
890 }
891 dn_maybe_reinit_mbufs(nmbuf, ncl, clsize);
892 }
893
894 /*
895 * Unfortunately, the ifnet_arrival_event eventhandler hook is mostly useless
896 * for us because drivers tend to if_attach before invoking DEBUGNET_SET().
897 *
898 * On the other hand, hooking DEBUGNET_SET() itself may still be too early,
899 * because the driver is still in attach. Since we cannot use down interfaces,
900 * maybe hooking ifnet_event:IFNET_EVENT_UP is sufficient? ... Nope, at least
901 * with vtnet and dhcpclient that event just never occurs.
902 *
903 * So that's how I've landed on the lower level ifnet_link_event.
904 */
905
906 static void
dn_ifnet_event(void * arg __unused,struct ifnet * ifp,int link_state)907 dn_ifnet_event(void *arg __unused, struct ifnet *ifp, int link_state)
908 {
909 if (link_state == LINK_STATE_UP)
910 debugnet_any_ifnet_update(ifp);
911 }
912
913 static eventhandler_tag dn_attach_cookie;
914 static void
dn_evh_init(void * ctx __unused)915 dn_evh_init(void *ctx __unused)
916 {
917 dn_attach_cookie = EVENTHANDLER_REGISTER(ifnet_link_event,
918 dn_ifnet_event, NULL, EVENTHANDLER_PRI_ANY);
919 }
920 SYSINIT(dn_evh_init, SI_SUB_EVENTHANDLER + 1, SI_ORDER_ANY, dn_evh_init, NULL);
921
922 /*
923 * DDB parsing helpers for debugnet(4) consumers.
924 */
925 #ifdef DDB
926 struct my_inet_opt {
927 bool has_opt;
928 const char *printname;
929 in_addr_t *result;
930 };
931
932 static int
dn_parse_optarg_ipv4(struct my_inet_opt * opt)933 dn_parse_optarg_ipv4(struct my_inet_opt *opt)
934 {
935 in_addr_t tmp;
936 unsigned octet;
937 int t;
938
939 tmp = 0;
940 for (octet = 0; octet < 4; octet++) {
941 t = db_read_token_flags(DRT_WSPACE | DRT_DECIMAL);
942 if (t != tNUMBER) {
943 db_printf("%s:%s: octet %u expected number; found %d\n",
944 __func__, opt->printname, octet, t);
945 return (EINVAL);
946 }
947 /*
948 * db_lex lexes '-' distinctly from the number itself, but
949 * let's document that invariant.
950 */
951 MPASS(db_tok_number >= 0);
952
953 if (db_tok_number > UINT8_MAX) {
954 db_printf("%s:%s: octet %u out of range: %jd\n", __func__,
955 opt->printname, octet, (intmax_t)db_tok_number);
956 return (EDOM);
957 }
958
959 /* Constructed host-endian and converted to network later. */
960 tmp = (tmp << 8) | db_tok_number;
961
962 if (octet < 3) {
963 t = db_read_token_flags(DRT_WSPACE);
964 if (t != tDOT) {
965 db_printf("%s:%s: octet %u expected '.'; found"
966 " %d\n", __func__, opt->printname, octet,
967 t);
968 return (EINVAL);
969 }
970 }
971 }
972
973 *opt->result = htonl(tmp);
974 opt->has_opt = true;
975 return (0);
976 }
977
978 int
debugnet_parse_ddb_cmd(const char * cmd,struct debugnet_ddb_config * result)979 debugnet_parse_ddb_cmd(const char *cmd, struct debugnet_ddb_config *result)
980 {
981 struct ifnet *ifp;
982 int t, error;
983 bool want_ifp;
984 char ch;
985
986 struct my_inet_opt opt_client = {
987 .printname = "client",
988 .result = &result->dd_client,
989 },
990 opt_server = {
991 .printname = "server",
992 .result = &result->dd_server,
993 },
994 opt_gateway = {
995 .printname = "gateway",
996 .result = &result->dd_gateway,
997 },
998 *cur_inet_opt;
999
1000 ifp = NULL;
1001 memset(result, 0, sizeof(*result));
1002
1003 /*
1004 * command [space] [-] [opt] [[space] [optarg]] ...
1005 *
1006 * db_command has already lexed 'command' for us.
1007 */
1008 t = db_read_token_flags(DRT_WSPACE);
1009 if (t == tWSPACE)
1010 t = db_read_token_flags(DRT_WSPACE);
1011
1012 while (t != tEOL) {
1013 if (t != tMINUS) {
1014 db_printf("%s: Bad syntax; expected '-', got %d\n",
1015 cmd, t);
1016 goto usage;
1017 }
1018
1019 t = db_read_token_flags(DRT_WSPACE);
1020 if (t != tIDENT) {
1021 db_printf("%s: Bad syntax; expected tIDENT, got %d\n",
1022 cmd, t);
1023 goto usage;
1024 }
1025
1026 if (strlen(db_tok_string) > 1) {
1027 db_printf("%s: Bad syntax; expected single option "
1028 "flag, got '%s'\n", cmd, db_tok_string);
1029 goto usage;
1030 }
1031
1032 want_ifp = false;
1033 cur_inet_opt = NULL;
1034 switch ((ch = db_tok_string[0])) {
1035 default:
1036 DNETDEBUG("Unexpected: '%c'\n", ch);
1037 /* FALLTHROUGH */
1038 case 'h':
1039 goto usage;
1040 case 'c':
1041 cur_inet_opt = &opt_client;
1042 break;
1043 case 'g':
1044 cur_inet_opt = &opt_gateway;
1045 break;
1046 case 's':
1047 cur_inet_opt = &opt_server;
1048 break;
1049 case 'i':
1050 want_ifp = true;
1051 break;
1052 }
1053
1054 t = db_read_token_flags(DRT_WSPACE);
1055 if (t != tWSPACE) {
1056 db_printf("%s: Bad syntax; expected space after "
1057 "flag %c, got %d\n", cmd, ch, t);
1058 goto usage;
1059 }
1060
1061 if (want_ifp) {
1062 t = db_read_token_flags(DRT_WSPACE);
1063 if (t != tIDENT) {
1064 db_printf("%s: Expected interface but got %d\n",
1065 cmd, t);
1066 goto usage;
1067 }
1068
1069 CURVNET_SET(vnet0);
1070 /*
1071 * We *don't* take a ref here because the only current
1072 * consumer, db_netdump_cmd, does not need it. It
1073 * (somewhat redundantly) extracts the if_name(),
1074 * re-lookups the ifp, and takes its own reference.
1075 */
1076 ifp = ifunit(db_tok_string);
1077 CURVNET_RESTORE();
1078 if (ifp == NULL) {
1079 db_printf("Could not locate interface %s\n",
1080 db_tok_string);
1081 error = ENOENT;
1082 goto cleanup;
1083 }
1084 } else {
1085 MPASS(cur_inet_opt != NULL);
1086 /* Assume IPv4 for now. */
1087 error = dn_parse_optarg_ipv4(cur_inet_opt);
1088 if (error != 0)
1089 goto cleanup;
1090 }
1091
1092 /* Skip (mandatory) whitespace after option, if not EOL. */
1093 t = db_read_token_flags(DRT_WSPACE);
1094 if (t == tEOL)
1095 break;
1096 if (t != tWSPACE) {
1097 db_printf("%s: Bad syntax; expected space after "
1098 "flag %c option; got %d\n", cmd, ch, t);
1099 goto usage;
1100 }
1101 t = db_read_token_flags(DRT_WSPACE);
1102 }
1103
1104 if (!opt_server.has_opt) {
1105 db_printf("%s: need a destination server address\n", cmd);
1106 goto usage;
1107 }
1108
1109 result->dd_has_client = opt_client.has_opt;
1110 result->dd_has_gateway = opt_gateway.has_opt;
1111 result->dd_ifp = ifp;
1112
1113 /* We parsed the full line to tEOL already, or bailed with an error. */
1114 return (0);
1115
1116 usage:
1117 db_printf("Usage: %s -s <server> [-g <gateway> -c <localip> "
1118 "-i <interface>]\n", cmd);
1119 error = EINVAL;
1120 /* FALLTHROUGH */
1121 cleanup:
1122 db_skip_to_eol();
1123 return (error);
1124 }
1125 #endif /* DDB */
1126