[mirror_ubuntu-bionic-kernel.git] / drivers / char / tpm / xen-tpmfront.c

/*
 * Implementation of the Xen vTPM device frontend
 *
 * Author:  Daniel De Graaf <dgdegra@tycho.nsa.gov>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2,
 * as published by the Free Software Foundation.
 */
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <xen/xen.h>
#include <xen/events.h>
#include <xen/interface/io/tpmif.h>
#include <xen/grant_table.h>
#include <xen/xenbus.h>
#include <xen/page.h>
#include "tpm.h"

struct tpm_private {
	struct tpm_chip *chip;
	struct xenbus_device *dev;

	struct vtpm_shared_page *shr;

	unsigned int evtchn;
	int ring_ref;
	domid_t backend_id;
};

enum status_bits {
	VTPM_STATUS_RUNNING  = 0x1,
	VTPM_STATUS_IDLE     = 0x2,
	VTPM_STATUS_RESULT   = 0x4,
	VTPM_STATUS_CANCELED = 0x8,
};

static u8 vtpm_status(struct tpm_chip *chip)
{
	struct tpm_private *priv = TPM_VPRIV(chip);
	switch (priv->shr->state) {
	case VTPM_STATE_IDLE:
		return VTPM_STATUS_IDLE | VTPM_STATUS_CANCELED;
	case VTPM_STATE_FINISH:
		return VTPM_STATUS_IDLE | VTPM_STATUS_RESULT;
	case VTPM_STATE_SUBMIT:
	case VTPM_STATE_CANCEL: /* cancel requested, not yet canceled */
		return VTPM_STATUS_RUNNING;
	default:
		return 0;
	}
}

static bool vtpm_req_canceled(struct tpm_chip *chip, u8 status)
{
	return status & VTPM_STATUS_CANCELED;
}

static void vtpm_cancel(struct tpm_chip *chip)
{
	struct tpm_private *priv = TPM_VPRIV(chip);
	priv->shr->state = VTPM_STATE_CANCEL;
	wmb();
	notify_remote_via_evtchn(priv->evtchn);
}

static unsigned int shr_data_offset(struct vtpm_shared_page *shr)
{
	return sizeof(*shr) + sizeof(u32) * shr->nr_extra_pages;
}

static int vtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
{
	struct tpm_private *priv = TPM_VPRIV(chip);
	struct vtpm_shared_page *shr = priv->shr;
	unsigned int offset = shr_data_offset(shr);

	u32 ordinal;
	unsigned long duration;

	if (offset > PAGE_SIZE)
		return -EINVAL;

	if (offset + count > PAGE_SIZE)
		return -EINVAL;

	/* Wait for completion of any existing command or cancellation */
	if (wait_for_tpm_stat(chip, VTPM_STATUS_IDLE, chip->vendor.timeout_c,
			&chip->vendor.read_queue, true) < 0) {
		vtpm_cancel(chip);
		return -ETIME;
	}

	memcpy(offset + (u8 *)shr, buf, count);
	shr->length = count;
	barrier();
	shr->state = VTPM_STATE_SUBMIT;
	wmb();
	notify_remote_via_evtchn(priv->evtchn);

	ordinal = be32_to_cpu(((struct tpm_input_header*)buf)->ordinal);
	duration = tpm_calc_ordinal_duration(chip, ordinal);

	if (wait_for_tpm_stat(chip, VTPM_STATUS_IDLE, duration,
			&chip->vendor.read_queue, true) < 0) {
		/* got a signal or timeout, try to cancel */
		vtpm_cancel(chip);
		return -ETIME;
	}

	return count;
}

static int vtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count)
{
	struct tpm_private *priv = TPM_VPRIV(chip);
	struct vtpm_shared_page *shr = priv->shr;
	unsigned int offset = shr_data_offset(shr);
	size_t length = shr->length;

	if (shr->state == VTPM_STATE_IDLE)
		return -ECANCELED;

	/* In theory the wait at the end of _send makes this one unnecessary */
	if (wait_for_tpm_stat(chip, VTPM_STATUS_RESULT, chip->vendor.timeout_c,
			&chip->vendor.read_queue, true) < 0) {
		vtpm_cancel(chip);
		return -ETIME;
	}

	if (offset > PAGE_SIZE)
		return -EIO;

	if (offset + length > PAGE_SIZE)
		length = PAGE_SIZE - offset;

	if (length > count)
		length = count;

	memcpy(buf, offset + (u8 *)shr, length);

	return length;
}

static const struct tpm_class_ops tpm_vtpm = {
	.status = vtpm_status,
	.recv = vtpm_recv,
	.send = vtpm_send,
	.cancel = vtpm_cancel,
	.req_complete_mask = VTPM_STATUS_IDLE | VTPM_STATUS_RESULT,
	.req_complete_val  = VTPM_STATUS_IDLE | VTPM_STATUS_RESULT,
	.req_canceled      = vtpm_req_canceled,
};

static irqreturn_t tpmif_interrupt(int dummy, void *dev_id)
{
	struct tpm_private *priv = dev_id;

	switch (priv->shr->state) {
	case VTPM_STATE_IDLE:
	case VTPM_STATE_FINISH:
		wake_up_interruptible(&priv->chip->vendor.read_queue);
		break;
	case VTPM_STATE_SUBMIT:
	case VTPM_STATE_CANCEL:
	default:
		break;
	}
	return IRQ_HANDLED;
}

static int setup_chip(struct device *dev, struct tpm_private *priv)
{
	struct tpm_chip *chip;

	chip = tpm_register_hardware(dev, &tpm_vtpm);
	if (!chip)
		return -ENODEV;

	init_waitqueue_head(&chip->vendor.read_queue);

	priv->chip = chip;
	TPM_VPRIV(chip) = priv;

	return 0;
}

/* caller must clean up in case of errors */
static int setup_ring(struct xenbus_device *dev, struct tpm_private *priv)
{
	struct xenbus_transaction xbt;
	const char *message = NULL;
	int rv;

	priv->shr = (void *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
	if (!priv->shr) {
		xenbus_dev_fatal(dev, -ENOMEM, "allocating shared ring");
		return -ENOMEM;
	}

	rv = xenbus_grant_ring(dev, virt_to_mfn(priv->shr));
	if (rv < 0)
		return rv;

	priv->ring_ref = rv;

	rv = xenbus_alloc_evtchn(dev, &priv->evtchn);
	if (rv)
		return rv;

	rv = bind_evtchn_to_irqhandler(priv->evtchn, tpmif_interrupt, 0,
				       "tpmif", priv);
	if (rv <= 0) {
		xenbus_dev_fatal(dev, rv, "allocating TPM irq");
		return rv;
	}
	priv->chip->vendor.irq = rv;

 again:
	rv = xenbus_transaction_start(&xbt);
	if (rv) {
		xenbus_dev_fatal(dev, rv, "starting transaction");
		return rv;
	}

	rv = xenbus_printf(xbt, dev->nodename,
			"ring-ref", "%u", priv->ring_ref);
	if (rv) {
		message = "writing ring-ref";
		goto abort_transaction;
	}

	rv = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
			priv->evtchn);
	if (rv) {
		message = "writing event-channel";
		goto abort_transaction;
	}

	rv = xenbus_printf(xbt, dev->nodename, "feature-protocol-v2", "1");
	if (rv) {
		message = "writing feature-protocol-v2";
		goto abort_transaction;
	}

	rv = xenbus_transaction_end(xbt, 0);
	if (rv == -EAGAIN)
		goto again;
	if (rv) {
		xenbus_dev_fatal(dev, rv, "completing transaction");
		return rv;
	}

	xenbus_switch_state(dev, XenbusStateInitialised);

	return 0;

 abort_transaction:
	xenbus_transaction_end(xbt, 1);
	if (message)
		xenbus_dev_error(dev, rv, "%s", message);

	return rv;
}

static void ring_free(struct tpm_private *priv)
{
	if (!priv)
		return;

	if (priv->ring_ref)
		gnttab_end_foreign_access(priv->ring_ref, 0,
				(unsigned long)priv->shr);
	else
		free_page((unsigned long)priv->shr);

	if (priv->chip && priv->chip->vendor.irq)
		unbind_from_irqhandler(priv->chip->vendor.irq, priv);

	kfree(priv);
}

static int tpmfront_probe(struct xenbus_device *dev,
		const struct xenbus_device_id *id)
{
	struct tpm_private *priv;
	int rv;

	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	if (!priv) {
		xenbus_dev_fatal(dev, -ENOMEM, "allocating priv structure");
		return -ENOMEM;
	}

	rv = setup_chip(&dev->dev, priv);
	if (rv) {
		kfree(priv);
		return rv;
	}

	rv = setup_ring(dev, priv);
	if (rv) {
		tpm_remove_hardware(&dev->dev);
		ring_free(priv);
		return rv;
	}

	tpm_get_timeouts(priv->chip);

	return rv;
}

static int tpmfront_remove(struct xenbus_device *dev)
{
	struct tpm_chip *chip = dev_get_drvdata(&dev->dev);
	struct tpm_private *priv = TPM_VPRIV(chip);
	tpm_remove_hardware(&dev->dev);
	ring_free(priv);
	TPM_VPRIV(chip) = NULL;
	return 0;
}

static int tpmfront_resume(struct xenbus_device *dev)
{
	/* A suspend/resume/migrate will interrupt a vTPM anyway */
	tpmfront_remove(dev);
	return tpmfront_probe(dev, NULL);
}

static void backend_changed(struct xenbus_device *dev,
		enum xenbus_state backend_state)
{
	int val;

	switch (backend_state) {
	case XenbusStateInitialised:
	case XenbusStateConnected:
		if (dev->state == XenbusStateConnected)
			break;

		if (xenbus_scanf(XBT_NIL, dev->otherend,
				"feature-protocol-v2", "%d", &val) < 0)
			val = 0;
		if (!val) {
			xenbus_dev_fatal(dev, -EINVAL,
					"vTPM protocol 2 required");
			return;
		}
		xenbus_switch_state(dev, XenbusStateConnected);
		break;

	case XenbusStateClosing:
	case XenbusStateClosed:
		device_unregister(&dev->dev);
		xenbus_frontend_closed(dev);
		break;
	default:
		break;
	}
}

static const struct xenbus_device_id tpmfront_ids[] = {
	{ "vtpm" },
	{ "" }
};
MODULE_ALIAS("xen:vtpm");

static DEFINE_XENBUS_DRIVER(tpmfront, ,
		.probe = tpmfront_probe,
		.remove = tpmfront_remove,
		.resume = tpmfront_resume,
		.otherend_changed = backend_changed,
	);

static int __init xen_tpmfront_init(void)
{
	if (!xen_domain())
		return -ENODEV;

	return xenbus_register_frontend(&tpmfront_driver);
}
module_init(xen_tpmfront_init);

static void __exit xen_tpmfront_exit(void)
{
	xenbus_unregister_driver(&tpmfront_driver);
}
module_exit(xen_tpmfront_exit);

MODULE_AUTHOR("Daniel De Graaf <dgdegra@tycho.nsa.gov>");
MODULE_DESCRIPTION("Xen vTPM Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
e2683957 DDG	1	/*
	2	* Implementation of the Xen vTPM device frontend
	3	*
	4	* Author: Daniel De Graaf <dgdegra@tycho.nsa.gov>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2,
	8	* as published by the Free Software Foundation.
	9	*/
	10	#include <linux/errno.h>
	11	#include <linux/err.h>
	12	#include <linux/interrupt.h>
8702c675	13	#include <xen/xen.h>
e2683957 DDG	14	#include <xen/events.h>
	15	#include <xen/interface/io/tpmif.h>
	16	#include <xen/grant_table.h>
	17	#include <xen/xenbus.h>
	18	#include <xen/page.h>
	19	#include "tpm.h"
	20
	21	struct tpm_private {
	22	struct tpm_chip *chip;
	23	struct xenbus_device *dev;
	24
	25	struct vtpm_shared_page *shr;
	26
	27	unsigned int evtchn;
	28	int ring_ref;
	29	domid_t backend_id;
	30	};
	31
	32	enum status_bits {
	33	VTPM_STATUS_RUNNING = 0x1,
	34	VTPM_STATUS_IDLE = 0x2,
	35	VTPM_STATUS_RESULT = 0x4,
	36	VTPM_STATUS_CANCELED = 0x8,
	37	};
	38
	39	static u8 vtpm_status(struct tpm_chip *chip)
	40	{
	41	struct tpm_private *priv = TPM_VPRIV(chip);
	42	switch (priv->shr->state) {
	43	case VTPM_STATE_IDLE:
	44	return VTPM_STATUS_IDLE \| VTPM_STATUS_CANCELED;
	45	case VTPM_STATE_FINISH:
	46	return VTPM_STATUS_IDLE \| VTPM_STATUS_RESULT;
	47	case VTPM_STATE_SUBMIT:
	48	case VTPM_STATE_CANCEL: /* cancel requested, not yet canceled */
	49	return VTPM_STATUS_RUNNING;
	50	default:
	51	return 0;
	52	}
	53	}
	54
	55	static bool vtpm_req_canceled(struct tpm_chip *chip, u8 status)
	56	{
	57	return status & VTPM_STATUS_CANCELED;
	58	}
	59
	60	static void vtpm_cancel(struct tpm_chip *chip)
	61	{
	62	struct tpm_private *priv = TPM_VPRIV(chip);
	63	priv->shr->state = VTPM_STATE_CANCEL;
	64	wmb();
	65	notify_remote_via_evtchn(priv->evtchn);
	66	}
	67
	68	static unsigned int shr_data_offset(struct vtpm_shared_page *shr)
	69	{
	70	return sizeof(shr) + sizeof(u32) shr->nr_extra_pages;
	71	}
	72
	73	static int vtpm_send(struct tpm_chip chip, u8 buf, size_t count)
	74	{
	75	struct tpm_private *priv = TPM_VPRIV(chip);
	76	struct vtpm_shared_page *shr = priv->shr;
	77	unsigned int offset = shr_data_offset(shr);
78
79	u32 ordinal;
80	unsigned long duration;
81
82	if (offset > PAGE_SIZE)
83	return -EINVAL;
84
85	if (offset + count > PAGE_SIZE)
86	return -EINVAL;
87
88	/* Wait for completion of any existing command or cancellation */
89	if (wait_for_tpm_stat(chip, VTPM_STATUS_IDLE, chip->vendor.timeout_c,
90	&chip->vendor.read_queue, true) < 0) {
91	vtpm_cancel(chip);
92	return -ETIME;
93	}
94
95	memcpy(offset + (u8 *)shr, buf, count);
96	shr->length = count;
97	barrier();
98	shr->state = VTPM_STATE_SUBMIT;
99	wmb();
100	notify_remote_via_evtchn(priv->evtchn);
101
102	ordinal = be32_to_cpu(((struct tpm_input_header*)buf)->ordinal);
103	duration = tpm_calc_ordinal_duration(chip, ordinal);
104
105	if (wait_for_tpm_stat(chip, VTPM_STATUS_IDLE, duration,
106	&chip->vendor.read_queue, true) < 0) {
107	/* got a signal or timeout, try to cancel */
108	vtpm_cancel(chip);
109	return -ETIME;
110	}
111
112	return count;
113	}
114
115	static int vtpm_recv(struct tpm_chip chip, u8 buf, size_t count)
116	{
117	struct tpm_private *priv = TPM_VPRIV(chip);
118	struct vtpm_shared_page *shr = priv->shr;
119	unsigned int offset = shr_data_offset(shr);
120	size_t length = shr->length;
121
122	if (shr->state == VTPM_STATE_IDLE)
123	return -ECANCELED;
124
125	/* In theory the wait at the end of _send makes this one unnecessary */
126	if (wait_for_tpm_stat(chip, VTPM_STATUS_RESULT, chip->vendor.timeout_c,
127	&chip->vendor.read_queue, true) < 0) {
128	vtpm_cancel(chip);
129	return -ETIME;
130	}
131
132	if (offset > PAGE_SIZE)
133	return -EIO;
134
135	if (offset + length > PAGE_SIZE)
136	length = PAGE_SIZE - offset;
137
138	if (length > count)
139	length = count;
140
141	memcpy(buf, offset + (u8 *)shr, length);
142
143	return length;
144	}
145
01ad1fa7	146	static const struct tpm_class_ops tpm_vtpm = {
e2683957 DDG	147	.status = vtpm_status,
	148	.recv = vtpm_recv,
	149	.send = vtpm_send,
	150	.cancel = vtpm_cancel,
	151	.req_complete_mask = VTPM_STATUS_IDLE \| VTPM_STATUS_RESULT,
	152	.req_complete_val = VTPM_STATUS_IDLE \| VTPM_STATUS_RESULT,
	153	.req_canceled = vtpm_req_canceled,
e2683957 DDG	154	};
	155
	156	static irqreturn_t tpmif_interrupt(int dummy, void *dev_id)
	157	{
	158	struct tpm_private *priv = dev_id;
	159
	160	switch (priv->shr->state) {
	161	case VTPM_STATE_IDLE:
	162	case VTPM_STATE_FINISH:
	163	wake_up_interruptible(&priv->chip->vendor.read_queue);
	164	break;
	165	case VTPM_STATE_SUBMIT:
	166	case VTPM_STATE_CANCEL:
	167	default:
	168	break;
	169	}
	170	return IRQ_HANDLED;
	171	}
	172
	173	static int setup_chip(struct device dev, struct tpm_private priv)
	174	{
	175	struct tpm_chip *chip;
	176
	177	chip = tpm_register_hardware(dev, &tpm_vtpm);
	178	if (!chip)
	179	return -ENODEV;
	180
	181	init_waitqueue_head(&chip->vendor.read_queue);
	182
	183	priv->chip = chip;
	184	TPM_VPRIV(chip) = priv;
	185
	186	return 0;
	187	}
	188
	189	/* caller must clean up in case of errors */
	190	static int setup_ring(struct xenbus_device dev, struct tpm_private priv)
	191	{
	192	struct xenbus_transaction xbt;
	193	const char *message = NULL;
	194	int rv;
	195
	196	priv->shr = (void *)__get_free_page(GFP_KERNEL\|__GFP_ZERO);
	197	if (!priv->shr) {
	198	xenbus_dev_fatal(dev, -ENOMEM, "allocating shared ring");
	199	return -ENOMEM;
	200	}
	201
	202	rv = xenbus_grant_ring(dev, virt_to_mfn(priv->shr));
	203	if (rv < 0)
	204	return rv;
	205
	206	priv->ring_ref = rv;
	207
	208	rv = xenbus_alloc_evtchn(dev, &priv->evtchn);
	209	if (rv)
	210	return rv;
	211
	212	rv = bind_evtchn_to_irqhandler(priv->evtchn, tpmif_interrupt, 0,
	213	"tpmif", priv);
	214	if (rv <= 0) {
	215	xenbus_dev_fatal(dev, rv, "allocating TPM irq");
	216	return rv;
	217	}
218	priv->chip->vendor.irq = rv;
219
220	again:
221	rv = xenbus_transaction_start(&xbt);
222	if (rv) {
223	xenbus_dev_fatal(dev, rv, "starting transaction");
224	return rv;
225	}
226
227	rv = xenbus_printf(xbt, dev->nodename,
228	"ring-ref", "%u", priv->ring_ref);
229	if (rv) {
230	message = "writing ring-ref";
231	goto abort_transaction;
232	}
233
234	rv = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
235	priv->evtchn);
236	if (rv) {
237	message = "writing event-channel";
238	goto abort_transaction;
239	}
240
241	rv = xenbus_printf(xbt, dev->nodename, "feature-protocol-v2", "1");
242	if (rv) {
243	message = "writing feature-protocol-v2";
244	goto abort_transaction;
245	}
246
247	rv = xenbus_transaction_end(xbt, 0);
248	if (rv == -EAGAIN)
249	goto again;
250	if (rv) {
251	xenbus_dev_fatal(dev, rv, "completing transaction");
252	return rv;
253	}
254
255	xenbus_switch_state(dev, XenbusStateInitialised);
256
257	return 0;
258
259	abort_transaction:
260	xenbus_transaction_end(xbt, 1);
261	if (message)
262	xenbus_dev_error(dev, rv, "%s", message);
263
264	return rv;
265	}
266
267	static void ring_free(struct tpm_private *priv)
268	{
269	if (!priv)
270	return;
271
272	if (priv->ring_ref)
273	gnttab_end_foreign_access(priv->ring_ref, 0,
274	(unsigned long)priv->shr);
275	else
276	free_page((unsigned long)priv->shr);
277
278	if (priv->chip && priv->chip->vendor.irq)
279	unbind_from_irqhandler(priv->chip->vendor.irq, priv);
280
281	kfree(priv);
282	}
283
284	static int tpmfront_probe(struct xenbus_device *dev,
285	const struct xenbus_device_id *id)
286	{
287	struct tpm_private *priv;
288	int rv;
289
290	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
291	if (!priv) {
292	xenbus_dev_fatal(dev, -ENOMEM, "allocating priv structure");
293	return -ENOMEM;
294	}
295
296	rv = setup_chip(&dev->dev, priv);
297	if (rv) {
298	kfree(priv);
299	return rv;
300	}
301
302	rv = setup_ring(dev, priv);
303	if (rv) {
304	tpm_remove_hardware(&dev->dev);
305	ring_free(priv);
306	return rv;
307	}
308
309	tpm_get_timeouts(priv->chip);
310
e2683957 DDG	311	return rv;
	312	}
	313
	314	static int tpmfront_remove(struct xenbus_device *dev)
	315	{
	316	struct tpm_chip *chip = dev_get_drvdata(&dev->dev);
	317	struct tpm_private *priv = TPM_VPRIV(chip);
	318	tpm_remove_hardware(&dev->dev);
	319	ring_free(priv);
	320	TPM_VPRIV(chip) = NULL;
	321	return 0;
	322	}
	323
	324	static int tpmfront_resume(struct xenbus_device *dev)
	325	{
	326	/* A suspend/resume/migrate will interrupt a vTPM anyway */
	327	tpmfront_remove(dev);
	328	return tpmfront_probe(dev, NULL);
	329	}
	330
	331	static void backend_changed(struct xenbus_device *dev,
	332	enum xenbus_state backend_state)
	333	{
	334	int val;
	335
	336	switch (backend_state) {
	337	case XenbusStateInitialised:
	338	case XenbusStateConnected:
	339	if (dev->state == XenbusStateConnected)
	340	break;
	341
	342	if (xenbus_scanf(XBT_NIL, dev->otherend,
	343	"feature-protocol-v2", "%d", &val) < 0)
	344	val = 0;
	345	if (!val) {
	346	xenbus_dev_fatal(dev, -EINVAL,
	347	"vTPM protocol 2 required");
	348	return;
	349	}
	350	xenbus_switch_state(dev, XenbusStateConnected);
	351	break;
	352
	353	case XenbusStateClosing:
	354	case XenbusStateClosed:
	355	device_unregister(&dev->dev);
	356	xenbus_frontend_closed(dev);
	357	break;
	358	default:
	359	break;
	360	}
	361	}
	362
	363	static const struct xenbus_device_id tpmfront_ids[] = {
	364	{ "vtpm" },
	365	{ "" }
	366	};
	367	MODULE_ALIAS("xen:vtpm");
	368
	369	static DEFINE_XENBUS_DRIVER(tpmfront, ,
	370	.probe = tpmfront_probe,
	371	.remove = tpmfront_remove,
	372	.resume = tpmfront_resume,
	373	.otherend_changed = backend_changed,
	374	);
375
376	static int __init xen_tpmfront_init(void)
377	{
378	if (!xen_domain())
379	return -ENODEV;
380
381	return xenbus_register_frontend(&tpmfront_driver);
382	}
383	module_init(xen_tpmfront_init);
384
385	static void __exit xen_tpmfront_exit(void)
386	{
387	xenbus_unregister_driver(&tpmfront_driver);
388	}
389	module_exit(xen_tpmfront_exit);
390
391	MODULE_AUTHOR("Daniel De Graaf <dgdegra@tycho.nsa.gov>");
392	MODULE_DESCRIPTION("Xen vTPM Driver");
393	MODULE_LICENSE("GPL");