1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (C) 2012 Ben Gray <bgray@freebsd.org>.
5 * Copyright (C) 2018 The FreeBSD Foundation.
6 * Copyright (c) 2019 Edward Tomasz Napierala <trasz@FreeBSD.org>
7 *
8 * This software was developed by Arshan Khanifar <arshankhanifar@gmail.com>
9 * under sponsorship from the FreeBSD Foundation.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33/*
34 * Universal Serial Bus Communications Class Subclass Specification
35 * for Ethernet Emulation Model Devices:
36 *
37 * https://usb.org/sites/default/files/CDC_EEM10.pdf
38 */
39
40#include <sys/cdefs.h>
41__FBSDID("$FreeBSD$");
42
43#include <sys/gsb_crc32.h>
44#include <sys/eventhandler.h>
45#include <sys/stdint.h>
46#include <sys/stddef.h>
47#include <sys/queue.h>
48#include <sys/systm.h>
49#include <sys/socket.h>
50#include <sys/kernel.h>
51#include <sys/bus.h>
52#include <sys/module.h>
53#include <sys/lock.h>
54#include <sys/mutex.h>
55#include <sys/condvar.h>
56#include <sys/sysctl.h>
57#include <sys/sx.h>
58#include <sys/unistd.h>
59#include <sys/callout.h>
60#include <sys/malloc.h>
61#include <sys/priv.h>
62
63#include <net/if.h>
64#include <net/if_var.h>
65
66#include <dev/usb/usb.h>
67#include <dev/usb/usbdi.h>
68#include <dev/usb/usbdi_util.h>
69#include <dev/usb/usb_cdc.h>
70#include "usbdevs.h"
71
72#define	USB_DEBUG_VAR cdceem_debug
73#include <dev/usb/usb_debug.h>
74#include <dev/usb/usb_process.h>
75#include <dev/usb/usb_msctest.h>
76#include "usb_if.h"
77
78#include <dev/usb/net/usb_ethernet.h>
79
80#define	CDCEEM_FRAMES_MAX	1
81#define	CDCEEM_ECHO_MAX		1024
82
83#define	CDCEEM_ECHO_PAYLOAD	\
84    "ICH DALEKOPIS FALSZUJE GDY PROBY XQV NIE WYTRZYMUJE 1234567890"
85
86enum {
87	CDCEEM_BULK_RX,
88	CDCEEM_BULK_TX,
89	CDCEEM_N_TRANSFER,
90};
91
92struct cdceem_softc {
93	struct usb_ether	sc_ue;
94	struct mtx		sc_mtx;
95	int			sc_flags;
96	struct usb_xfer		*sc_xfer[CDCEEM_N_TRANSFER];
97	size_t			sc_echo_len;
98	char			sc_echo_buffer[CDCEEM_ECHO_MAX];
99};
100
101#define	CDCEEM_SC_FLAGS_ECHO_RESPONSE_PENDING	0x1
102#define	CDCEEM_SC_FLAGS_ECHO_PENDING		0x2
103
104static SYSCTL_NODE(_hw_usb, OID_AUTO, cdceem, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
105    "USB CDC EEM");
106static int cdceem_debug = 1;
107SYSCTL_INT(_hw_usb_cdceem, OID_AUTO, debug, CTLFLAG_RWTUN,
108    &cdceem_debug, 0, "Debug level");
109static int cdceem_send_echoes = 0;
110SYSCTL_INT(_hw_usb_cdceem, OID_AUTO, send_echoes, CTLFLAG_RWTUN,
111    &cdceem_send_echoes, 0, "Send an Echo command");
112static int cdceem_send_fake_crc = 0;
113SYSCTL_INT(_hw_usb_cdceem, OID_AUTO, send_fake_crc, CTLFLAG_RWTUN,
114    &cdceem_send_fake_crc, 0, "Use 0xdeadbeef instead of CRC");
115
116#define	CDCEEM_DEBUG(S, X, ...)						\
117	do {								\
118		if (cdceem_debug > 1) {					\
119			device_printf(S->sc_ue.ue_dev, "%s: " X "\n",	\
120			    __func__, ## __VA_ARGS__);			\
121		}							\
122	} while (0)
123
124#define	CDCEEM_WARN(S, X, ...)						\
125	do {								\
126		if (cdceem_debug > 0) {					\
127			device_printf(S->sc_ue.ue_dev,			\
128			    "WARNING: %s: " X "\n",			\
129			    __func__, ## __VA_ARGS__);			\
130		}							\
131	} while (0)
132
133#define	CDCEEM_LOCK(X)				mtx_lock(&(X)->sc_mtx)
134#define	CDCEEM_UNLOCK(X)			mtx_unlock(&(X)->sc_mtx)
135
136#define	CDCEEM_TYPE_CMD				(0x1 << 15)
137
138#define	CDCEEM_CMD_MASK				(0x7 << 11)
139
140#define	CDCEEM_CMD_ECHO				(0x0 << 11)
141#define	CDCEEM_CMD_ECHO_RESPONSE		(0x1 << 11)
142#define	CDCEEM_CMD_SUSPEND_HINT			(0x2 << 11)
143#define	CDCEEM_CMD_RESPONSE_HINT		(0x3 << 11)
144#define	CDCEEM_CMD_RESPONSE_COMPLETE_HINT	(0x4 << 11)
145#define	CDCEEM_CMD_TICKLE			(0x5 << 11)
146
147#define	CDCEEM_CMD_RESERVED			(0x1 << 14)
148
149#define	CDCEEM_ECHO_LEN_MASK			0x3ff
150
151#define	CDCEEM_DATA_CRC				(0x1 << 14)
152#define	CDCEEM_DATA_LEN_MASK			0x3fff
153
154static device_probe_t cdceem_probe;
155static device_attach_t cdceem_attach;
156static device_detach_t cdceem_detach;
157static device_suspend_t cdceem_suspend;
158static device_resume_t cdceem_resume;
159
160static usb_callback_t cdceem_bulk_write_callback;
161static usb_callback_t cdceem_bulk_read_callback;
162
163static uether_fn_t cdceem_attach_post;
164static uether_fn_t cdceem_init;
165static uether_fn_t cdceem_stop;
166static uether_fn_t cdceem_start;
167static uether_fn_t cdceem_setmulti;
168static uether_fn_t cdceem_setpromisc;
169
170static uint32_t	cdceem_m_crc32(struct mbuf *, uint32_t, uint32_t);
171
172static const struct usb_config cdceem_config[CDCEEM_N_TRANSFER] = {
173	[CDCEEM_BULK_TX] = {
174		.type = UE_BULK,
175		.endpoint = UE_ADDR_ANY,
176		.direction = UE_DIR_TX,
177		.bufsize = 16 * (MCLBYTES + 16),
178		.flags = {.pipe_bof = 1,.force_short_xfer = 1,},
179		.callback = cdceem_bulk_write_callback,
180		.timeout = 10000,	/* 10 seconds */
181		.usb_mode = USB_MODE_DUAL,
182	},
183
184	[CDCEEM_BULK_RX] = {
185		.type = UE_BULK,
186		.endpoint = UE_ADDR_ANY,
187		.direction = UE_DIR_RX,
188		.bufsize = 20480,	/* bytes */
189		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
190		.callback = cdceem_bulk_read_callback,
191		.timeout = 0,	/* no timeout */
192		.usb_mode = USB_MODE_DUAL,
193	},
194};
195
196static device_method_t cdceem_methods[] = {
197	/* Device interface */
198	DEVMETHOD(device_probe, cdceem_probe),
199	DEVMETHOD(device_attach, cdceem_attach),
200	DEVMETHOD(device_detach, cdceem_detach),
201	DEVMETHOD(device_suspend, cdceem_suspend),
202	DEVMETHOD(device_resume, cdceem_resume),
203
204	DEVMETHOD_END
205};
206
207static driver_t cdceem_driver = {
208	.name = "cdceem",
209	.methods = cdceem_methods,
210	.size = sizeof(struct cdceem_softc),
211};
212
213static devclass_t cdceem_devclass;
214
215static const STRUCT_USB_DUAL_ID cdceem_dual_devs[] = {
216	{USB_IFACE_CLASS(UICLASS_CDC),
217		USB_IFACE_SUBCLASS(UISUBCLASS_ETHERNET_EMULATION_MODEL),
218		0},
219};
220
221DRIVER_MODULE(cdceem, uhub, cdceem_driver, cdceem_devclass, NULL, NULL);
222MODULE_VERSION(cdceem, 1);
223MODULE_DEPEND(cdceem, uether, 1, 1, 1);
224MODULE_DEPEND(cdceem, usb, 1, 1, 1);
225MODULE_DEPEND(cdceem, ether, 1, 1, 1);
226USB_PNP_DUAL_INFO(cdceem_dual_devs);
227
228static const struct usb_ether_methods cdceem_ue_methods = {
229	.ue_attach_post = cdceem_attach_post,
230	.ue_start = cdceem_start,
231	.ue_init = cdceem_init,
232	.ue_stop = cdceem_stop,
233	.ue_setmulti = cdceem_setmulti,
234	.ue_setpromisc = cdceem_setpromisc,
235};
236
237static int
238cdceem_probe(device_t dev)
239{
240	struct usb_attach_arg *uaa;
241	int error;
242
243	uaa = device_get_ivars(dev);
244	error = usbd_lookup_id_by_uaa(cdceem_dual_devs,
245	    sizeof(cdceem_dual_devs), uaa);
246
247	return (error);
248}
249
250static void
251cdceem_attach_post(struct usb_ether *ue)
252{
253
254	return;
255}
256
257static int
258cdceem_attach(device_t dev)
259{
260	struct cdceem_softc *sc;
261	struct usb_ether *ue;
262	struct usb_attach_arg *uaa;
263	int error;
264	uint8_t iface_index;
265
266	sc = device_get_softc(dev);
267	ue = &sc->sc_ue;
268	uaa = device_get_ivars(dev);
269
270	device_set_usb_desc(dev);
271
272	mtx_init(&sc->sc_mtx, device_get_nameunit(dev), NULL, MTX_DEF);
273
274	/* Setup the endpoints. */
275	iface_index = 0;
276	error = usbd_transfer_setup(uaa->device, &iface_index, sc->sc_xfer,
277	    cdceem_config, CDCEEM_N_TRANSFER, sc, &sc->sc_mtx);
278	if (error != 0) {
279		CDCEEM_WARN(sc,
280		    "allocating USB transfers failed, error %d", error);
281		mtx_destroy(&sc->sc_mtx);
282		return (error);
283	}
284
285	/* Random MAC address. */
286	arc4rand(ue->ue_eaddr, ETHER_ADDR_LEN, 0);
287	ue->ue_eaddr[0] &= ~0x01;	/* unicast */
288	ue->ue_eaddr[0] |= 0x02;	/* locally administered */
289
290	ue->ue_sc = sc;
291	ue->ue_dev = dev;
292	ue->ue_udev = uaa->device;
293	ue->ue_mtx = &sc->sc_mtx;
294	ue->ue_methods = &cdceem_ue_methods;
295
296	error = uether_ifattach(ue);
297	if (error != 0) {
298		CDCEEM_WARN(sc, "could not attach interface, error %d", error);
299		usbd_transfer_unsetup(sc->sc_xfer, CDCEEM_N_TRANSFER);
300		mtx_destroy(&sc->sc_mtx);
301		return (error);
302	}
303
304	return (0);
305}
306
307static int
308cdceem_detach(device_t dev)
309{
310	struct cdceem_softc *sc = device_get_softc(dev);
311	struct usb_ether *ue = &sc->sc_ue;
312
313	/* Stop all USB transfers first. */
314	usbd_transfer_unsetup(sc->sc_xfer, CDCEEM_N_TRANSFER);
315	uether_ifdetach(ue);
316	mtx_destroy(&sc->sc_mtx);
317
318	return (0);
319}
320
321static void
322cdceem_handle_cmd(struct usb_xfer *xfer, uint16_t hdr, int *offp)
323{
324	struct cdceem_softc *sc;
325	struct usb_page_cache *pc;
326	int actlen, off;
327	uint16_t pktlen;
328
329	off = *offp;
330	sc = usbd_xfer_softc(xfer);
331	pc = usbd_xfer_get_frame(xfer, 0);
332	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
333
334	if (hdr & CDCEEM_CMD_RESERVED) {
335		CDCEEM_WARN(sc, "received command header %#x "
336		    "with Reserved bit set; ignoring", hdr);
337		return;
338	}
339
340	switch (hdr & CDCEEM_CMD_MASK) {
341	case CDCEEM_CMD_ECHO:
342		pktlen = hdr & CDCEEM_ECHO_LEN_MASK;
343		CDCEEM_DEBUG(sc, "received Echo, length %d", pktlen);
344
345		if (pktlen > (actlen - off)) {
346			CDCEEM_WARN(sc,
347			    "bad Echo length %d, should be at most %d",
348			    pktlen, actlen - off);
349			break;
350		}
351
352		if (pktlen > sizeof(sc->sc_echo_buffer)) {
353			CDCEEM_WARN(sc,
354			    "Echo length %u too big, must be less than %zd",
355			    pktlen, sizeof(sc->sc_echo_buffer));
356			break;
357		}
358
359		sc->sc_flags |= CDCEEM_SC_FLAGS_ECHO_RESPONSE_PENDING;
360		sc->sc_echo_len = pktlen;
361		usbd_copy_out(pc, off, sc->sc_echo_buffer, pktlen);
362		off += pktlen;
363		break;
364
365	case CDCEEM_CMD_ECHO_RESPONSE:
366		pktlen = hdr & CDCEEM_ECHO_LEN_MASK;
367		CDCEEM_DEBUG(sc, "received Echo Response, length %d", pktlen);
368
369		if (pktlen > (actlen - off)) {
370			CDCEEM_WARN(sc,
371			    "bad Echo Response length %d, "
372			    "should be at most %d",
373			    pktlen, actlen - off);
374			break;
375		}
376
377		if (pktlen != sizeof(CDCEEM_ECHO_PAYLOAD)) {
378			CDCEEM_WARN(sc, "received Echo Response with bad "
379			    "length %hu, should be %zd",
380			    pktlen, sizeof(CDCEEM_ECHO_PAYLOAD));
381			break;
382		}
383
384		usbd_copy_out(pc, off, sc->sc_echo_buffer, pktlen);
385		off += pktlen;
386
387		if (memcmp(sc->sc_echo_buffer, CDCEEM_ECHO_PAYLOAD,
388		    sizeof(CDCEEM_ECHO_PAYLOAD)) != 0) {
389			CDCEEM_WARN(sc,
390			    "received Echo Response payload does not match");
391		} else {
392			CDCEEM_DEBUG(sc, "received Echo Response is valid");
393		}
394		break;
395
396	case CDCEEM_CMD_SUSPEND_HINT:
397		CDCEEM_DEBUG(sc, "received SuspendHint; ignoring");
398		break;
399
400	case CDCEEM_CMD_RESPONSE_HINT:
401		CDCEEM_DEBUG(sc, "received ResponseHint; ignoring");
402		break;
403
404	case CDCEEM_CMD_RESPONSE_COMPLETE_HINT:
405		CDCEEM_DEBUG(sc, "received ResponseCompleteHint; ignoring");
406		break;
407
408	case CDCEEM_CMD_TICKLE:
409		CDCEEM_DEBUG(sc, "received Tickle; ignoring");
410		break;
411
412	default:
413		CDCEEM_WARN(sc,
414		    "received unknown command %u, header %#x; ignoring",
415		    (hdr & CDCEEM_CMD_MASK >> 11), hdr);
416		break;
417	}
418
419	*offp = off;
420}
421
422static void
423cdceem_handle_data(struct usb_xfer *xfer, uint16_t hdr, int *offp)
424{
425	struct cdceem_softc *sc;
426	struct usb_page_cache *pc;
427	struct usb_ether *ue;
428	struct ifnet *ifp;
429	struct mbuf *m;
430	uint32_t computed_crc, received_crc;
431	int pktlen;
432	int actlen;
433	int off;
434
435	off = *offp;
436	sc = usbd_xfer_softc(xfer);
437	pc = usbd_xfer_get_frame(xfer, 0);
438	ue = &sc->sc_ue;
439	ifp = uether_getifp(ue);
440	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
441
442	pktlen = hdr & CDCEEM_DATA_LEN_MASK;
443	CDCEEM_DEBUG(sc, "received Data, CRC %s, length %d",
444	    (hdr & CDCEEM_DATA_CRC) ? "valid" : "absent",
445	    pktlen);
446
447	if (pktlen < (ETHER_HDR_LEN + 4)) {
448		CDCEEM_WARN(sc,
449		    "bad ethernet frame length %d, should be at least %d",
450		    pktlen, ETHER_HDR_LEN);
451		if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
452		return;
453	}
454
455	if (pktlen > (actlen - off)) {
456		CDCEEM_WARN(sc,
457		    "bad ethernet frame length %d, should be at most %d",
458		    pktlen, actlen - off);
459		if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
460		return;
461	}
462
463	m = uether_newbuf();
464	if (m == NULL) {
465		CDCEEM_WARN(sc, "uether_newbuf() failed");
466		if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
467		return;
468	}
469
470	pktlen -= 4; /* Subtract the CRC. */
471
472	if (pktlen > m->m_len) {
473		CDCEEM_WARN(sc, "buffer too small %d vs %d bytes",
474		    pktlen, m->m_len);
475		if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
476		m_freem(m);
477		return;
478	}
479	usbd_copy_out(pc, off, mtod(m, uint8_t *), pktlen);
480	off += pktlen;
481
482	usbd_copy_out(pc, off, &received_crc, sizeof(received_crc));
483	off += sizeof(received_crc);
484
485	if (hdr & CDCEEM_DATA_CRC) {
486		computed_crc = cdceem_m_crc32(m, 0, pktlen);
487	} else {
488		computed_crc = be32toh(0xdeadbeef);
489	}
490
491	if (received_crc != computed_crc) {
492		CDCEEM_WARN(sc,
493		    "received Data packet with wrong CRC %#x, expected %#x",
494		    received_crc, computed_crc);
495		if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
496		m_freem(m);
497		return;
498	} else {
499		CDCEEM_DEBUG(sc, "received correct CRC %#x", received_crc);
500	}
501
502	uether_rxmbuf(ue, m, pktlen);
503	*offp = off;
504}
505
506static void
507cdceem_bulk_read_callback(struct usb_xfer *xfer, usb_error_t usb_error)
508{
509	struct cdceem_softc *sc;
510	struct usb_page_cache *pc;
511	int actlen, aframes, off;
512	uint16_t hdr;
513
514	sc = usbd_xfer_softc(xfer);
515	usbd_xfer_status(xfer, &actlen, NULL, &aframes, NULL);
516
517	switch (USB_GET_STATE(xfer)) {
518	case USB_ST_TRANSFERRED:
519		CDCEEM_DEBUG(sc,
520		    "received %u bytes in %u frames", actlen, aframes);
521
522		pc = usbd_xfer_get_frame(xfer, 0);
523		off = 0;
524
525		while ((off + sizeof(hdr)) <= actlen) {
526			usbd_copy_out(pc, off, &hdr, sizeof(hdr));
527			CDCEEM_DEBUG(sc, "hdr = %#x", hdr);
528			off += sizeof(hdr);
529
530			if (hdr == 0) {
531				CDCEEM_DEBUG(sc, "received Zero Length EEM");
532				continue;
533			}
534
535			hdr = le16toh(hdr);
536
537			if ((hdr & CDCEEM_TYPE_CMD) != 0) {
538				cdceem_handle_cmd(xfer, hdr, &off);
539			} else {
540				cdceem_handle_data(xfer, hdr, &off);
541			}
542
543			KASSERT(off <= actlen,
544			    ("%s: went past the buffer, off %d, actlen %d",
545			     __func__, off, actlen));
546		}
547
548		/* FALLTHROUGH */
549	case USB_ST_SETUP:
550		CDCEEM_DEBUG(sc, "setup");
551tr_setup:
552		usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
553		usbd_transfer_submit(xfer);
554		uether_rxflush(&sc->sc_ue);
555		break;
556
557	default:
558		CDCEEM_WARN(sc, "USB_ST_ERROR: %s", usbd_errstr(usb_error));
559
560		if (usb_error != USB_ERR_CANCELLED) {
561			/* try to clear stall first */
562			usbd_xfer_set_stall(xfer);
563			goto tr_setup;
564		}
565		break;
566	}
567}
568
569static void
570cdceem_send_echo(struct usb_xfer *xfer, int *offp)
571{
572	struct cdceem_softc *sc;
573	struct usb_page_cache *pc;
574	int maxlen, off;
575	uint16_t hdr;
576
577	off = *offp;
578	sc = usbd_xfer_softc(xfer);
579	pc = usbd_xfer_get_frame(xfer, 0);
580	maxlen = usbd_xfer_max_len(xfer);
581
582	CDCEEM_DEBUG(sc, "sending Echo, length %zd",
583	    sizeof(CDCEEM_ECHO_PAYLOAD));
584
585	KASSERT(off + sizeof(hdr) + sizeof(CDCEEM_ECHO_PAYLOAD) < maxlen,
586	    ("%s: out of space; have %d, need %zd", __func__, maxlen,
587	    off + sizeof(hdr) + sizeof(CDCEEM_ECHO_PAYLOAD)));
588
589	hdr = 0;
590	hdr |= CDCEEM_TYPE_CMD;
591	hdr |= CDCEEM_CMD_ECHO;
592	hdr |= sizeof(CDCEEM_ECHO_PAYLOAD);
593	CDCEEM_DEBUG(sc, "hdr = %#x", hdr);
594	hdr = htole16(hdr);
595
596	usbd_copy_in(pc, off, &hdr, sizeof(hdr));
597	off += sizeof(hdr);
598
599	usbd_copy_in(pc, off, CDCEEM_ECHO_PAYLOAD,
600	    sizeof(CDCEEM_ECHO_PAYLOAD));
601	off += sizeof(CDCEEM_ECHO_PAYLOAD);
602
603	sc->sc_flags &= ~CDCEEM_SC_FLAGS_ECHO_PENDING;
604
605	*offp = off;
606}
607
608static void
609cdceem_send_echo_response(struct usb_xfer *xfer, int *offp)
610{
611	struct cdceem_softc *sc;
612	struct usb_page_cache *pc;
613	int maxlen, off;
614	uint16_t hdr;
615
616	off = *offp;
617	sc = usbd_xfer_softc(xfer);
618	pc = usbd_xfer_get_frame(xfer, 0);
619	maxlen = usbd_xfer_max_len(xfer);
620
621	KASSERT(off + sizeof(hdr) + sc->sc_echo_len < maxlen,
622	    ("%s: out of space; have %d, need %zd", __func__, maxlen,
623	    off + sizeof(hdr) + sc->sc_echo_len));
624
625	CDCEEM_DEBUG(sc, "sending Echo Response, length %zd", sc->sc_echo_len);
626
627	hdr = 0;
628	hdr |= CDCEEM_TYPE_CMD;
629	hdr |= CDCEEM_CMD_ECHO_RESPONSE;
630	hdr |= sc->sc_echo_len;
631	CDCEEM_DEBUG(sc, "hdr = %#x", hdr);
632	hdr = htole16(hdr);
633
634	usbd_copy_in(pc, off, &hdr, sizeof(hdr));
635	off += sizeof(hdr);
636
637	usbd_copy_in(pc, off, sc->sc_echo_buffer, sc->sc_echo_len);
638	off += sc->sc_echo_len;
639
640	sc->sc_flags &= ~CDCEEM_SC_FLAGS_ECHO_RESPONSE_PENDING;
641	sc->sc_echo_len = 0;
642
643	*offp = off;
644}
645
646static void
647cdceem_send_data(struct usb_xfer *xfer, int *offp)
648{
649	struct cdceem_softc *sc;
650	struct usb_page_cache *pc;
651	struct ifnet *ifp;
652	struct mbuf *m;
653	int maxlen, off;
654	uint32_t crc;
655	uint16_t hdr;
656
657	off = *offp;
658	sc = usbd_xfer_softc(xfer);
659	pc = usbd_xfer_get_frame(xfer, 0);
660	ifp = uether_getifp(&sc->sc_ue);
661	maxlen = usbd_xfer_max_len(xfer);
662
663	IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
664	if (m == NULL) {
665		CDCEEM_DEBUG(sc, "no Data packets to send");
666		return;
667	}
668
669	KASSERT((m->m_pkthdr.len & CDCEEM_DATA_LEN_MASK) == m->m_pkthdr.len,
670	    ("%s: packet too long: %d, should be %d\n", __func__,
671	     m->m_pkthdr.len, m->m_pkthdr.len & CDCEEM_DATA_LEN_MASK));
672	KASSERT(off + sizeof(hdr) + m->m_pkthdr.len + 4 < maxlen,
673	    ("%s: out of space; have %d, need %zd", __func__, maxlen,
674	    off + sizeof(hdr) + m->m_pkthdr.len + 4));
675
676	CDCEEM_DEBUG(sc, "sending Data, length %d + 4", m->m_pkthdr.len);
677
678	hdr = 0;
679	if (!cdceem_send_fake_crc)
680		hdr |= CDCEEM_DATA_CRC;
681	hdr |= (m->m_pkthdr.len + 4); /* +4 for CRC */
682	CDCEEM_DEBUG(sc, "hdr = %#x", hdr);
683	hdr = htole16(hdr);
684
685	usbd_copy_in(pc, off, &hdr, sizeof(hdr));
686	off += sizeof(hdr);
687
688	usbd_m_copy_in(pc, off, m, 0, m->m_pkthdr.len);
689	off += m->m_pkthdr.len;
690
691	if (cdceem_send_fake_crc) {
692		crc = htobe32(0xdeadbeef);
693	} else {
694		crc = cdceem_m_crc32(m, 0, m->m_pkthdr.len);
695	}
696	CDCEEM_DEBUG(sc, "CRC = %#x", crc);
697
698	usbd_copy_in(pc, off, &crc, sizeof(crc));
699	off += sizeof(crc);
700
701	if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
702
703	/*
704	 * If there's a BPF listener, bounce a copy of this frame to it.
705	 */
706	BPF_MTAP(ifp, m);
707	m_freem(m);
708
709	*offp = off;
710}
711
712static void
713cdceem_bulk_write_callback(struct usb_xfer *xfer, usb_error_t usb_error)
714{
715	struct cdceem_softc *sc;
716	struct ifnet *ifp;
717	int actlen, aframes, maxlen, off;
718
719	sc = usbd_xfer_softc(xfer);
720	maxlen = usbd_xfer_max_len(xfer);
721
722	switch (USB_GET_STATE(xfer)) {
723	case USB_ST_TRANSFERRED:
724		usbd_xfer_status(xfer, &actlen, NULL, &aframes, NULL);
725		CDCEEM_DEBUG(sc, "transferred %u bytes in %u frames",
726		    actlen, aframes);
727
728		/* FALLTHROUGH */
729	case USB_ST_SETUP:
730		CDCEEM_DEBUG(sc, "setup");
731tr_setup:
732
733		off = 0;
734		usbd_xfer_set_frame_offset(xfer, 0, 0);
735
736		if (sc->sc_flags & CDCEEM_SC_FLAGS_ECHO_PENDING) {
737			cdceem_send_echo(xfer, &off);
738		} else if (sc->sc_flags & CDCEEM_SC_FLAGS_ECHO_RESPONSE_PENDING) {
739			cdceem_send_echo_response(xfer, &off);
740		} else {
741			cdceem_send_data(xfer, &off);
742		}
743
744		KASSERT(off <= maxlen,
745		    ("%s: went past the buffer, off %d, maxlen %d",
746		     __func__, off, maxlen));
747
748		if (off > 0) {
749			CDCEEM_DEBUG(sc, "starting transfer, length %d", off);
750			usbd_xfer_set_frame_len(xfer, 0, off);
751			usbd_transfer_submit(xfer);
752		} else {
753			CDCEEM_DEBUG(sc, "nothing to transfer");
754		}
755
756		break;
757
758	default:
759		CDCEEM_WARN(sc, "USB_ST_ERROR: %s", usbd_errstr(usb_error));
760
761		ifp = uether_getifp(&sc->sc_ue);
762		if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
763
764		if (usb_error != USB_ERR_CANCELLED) {
765			/* try to clear stall first */
766			usbd_xfer_set_stall(xfer);
767			goto tr_setup;
768		}
769		break;
770	}
771}
772
773static int32_t
774cdceem_m_crc32_cb(void *arg, void *src, uint32_t count)
775{
776	uint32_t *p_crc = arg;
777
778	*p_crc = crc32_raw(src, count, *p_crc);
779	return (0);
780}
781
782static uint32_t
783cdceem_m_crc32(struct mbuf *m, uint32_t src_offset, uint32_t src_len)
784{
785	uint32_t crc = 0xFFFFFFFF;
786	int error;
787
788	error = m_apply(m, src_offset, src_len, cdceem_m_crc32_cb, &crc);
789	return (crc ^ 0xFFFFFFFF);
790}
791
792static void
793cdceem_start(struct usb_ether *ue)
794{
795	struct cdceem_softc *sc;
796
797	sc = uether_getsc(ue);
798
799	/*
800	 * Start the USB transfers, if not already started.
801	 */
802	usbd_transfer_start(sc->sc_xfer[CDCEEM_BULK_RX]);
803	usbd_transfer_start(sc->sc_xfer[CDCEEM_BULK_TX]);
804}
805
806static void
807cdceem_init(struct usb_ether *ue)
808{
809	struct cdceem_softc *sc;
810	struct ifnet *ifp;
811
812	sc = uether_getsc(ue);
813	ifp = uether_getifp(ue);
814
815	ifp->if_drv_flags |= IFF_DRV_RUNNING;
816
817	if (cdceem_send_echoes)
818		sc->sc_flags = CDCEEM_SC_FLAGS_ECHO_PENDING;
819	else
820		sc->sc_flags = 0;
821
822	/*
823	 * Stall data write direction, which depends on USB mode.
824	 *
825	 * Some USB host stacks (e.g. Mac OS X) don't clears stall
826	 * bit as it should, so set it in our host mode only.
827	 */
828	if (usbd_get_mode(sc->sc_ue.ue_udev) == USB_MODE_HOST)
829		usbd_xfer_set_stall(sc->sc_xfer[CDCEEM_BULK_TX]);
830
831	cdceem_start(ue);
832}
833
834static void
835cdceem_stop(struct usb_ether *ue)
836{
837	struct cdceem_softc *sc;
838	struct ifnet *ifp;
839
840	sc = uether_getsc(ue);
841	ifp = uether_getifp(ue);
842
843	ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
844
845	usbd_transfer_stop(sc->sc_xfer[CDCEEM_BULK_RX]);
846	usbd_transfer_stop(sc->sc_xfer[CDCEEM_BULK_TX]);
847}
848
849static void
850cdceem_setmulti(struct usb_ether *ue)
851{
852	/* no-op */
853	return;
854}
855
856static void
857cdceem_setpromisc(struct usb_ether *ue)
858{
859	/* no-op */
860	return;
861}
862
863static int
864cdceem_suspend(device_t dev)
865{
866	struct cdceem_softc *sc = device_get_softc(dev);
867
868	CDCEEM_DEBUG(sc, "go");
869	return (0);
870}
871
872static int
873cdceem_resume(device_t dev)
874{
875	struct cdceem_softc *sc = device_get_softc(dev);
876
877	CDCEEM_DEBUG(sc, "go");
878	return (0);
879}
880