1 /*
2 * Copyright (C) 2010 Michael Brown <mbrown@fensystems.co.uk>.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17 * 02110-1301, USA.
18 *
19 * You can also choose to distribute this program under the terms of
20 * the Unmodified Binary Distribution Licence (as given in the file
21 * COPYING.UBDL), provided that you have satisfied its requirements.
22 */
23
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25
26 #include <stdint.h>
27 #include <string.h>
28 #include <stdio.h>
29 #include <errno.h>
30 #include <byteswap.h>
31 #include <ipxe/features.h>
32 #include <ipxe/if_ether.h>
33 #include <ipxe/ethernet.h>
34 #include <ipxe/netdevice.h>
35 #include <ipxe/iobuf.h>
36 #include <ipxe/vlan.h>
37
38 /** @file
39 *
40 * Virtual LANs
41 *
42 */
43
44 FEATURE ( FEATURE_PROTOCOL, "VLAN", DHCP_EB_FEATURE_VLAN, 1 );
45
46 struct net_protocol vlan_protocol __net_protocol;
47
48 /** VLAN device private data */
49 struct vlan_device {
50 /** Trunk network device */
51 struct net_device *trunk;
52 /** VLAN tag */
53 unsigned int tag;
54 /** Default priority */
55 unsigned int priority;
56 };
57
58 /**
59 * Open VLAN device
60 *
61 * @v netdev Network device
62 * @ret rc Return status code
63 */
vlan_open(struct net_device * netdev)64 static int vlan_open ( struct net_device *netdev ) {
65 struct vlan_device *vlan = netdev->priv;
66
67 return netdev_open ( vlan->trunk );
68 }
69
70 /**
71 * Close VLAN device
72 *
73 * @v netdev Network device
74 */
vlan_close(struct net_device * netdev)75 static void vlan_close ( struct net_device *netdev ) {
76 struct vlan_device *vlan = netdev->priv;
77
78 netdev_close ( vlan->trunk );
79 }
80
81 /**
82 * Transmit packet on VLAN device
83 *
84 * @v netdev Network device
85 * @v iobuf I/O buffer
86 * @ret rc Return status code
87 */
vlan_transmit(struct net_device * netdev,struct io_buffer * iobuf)88 static int vlan_transmit ( struct net_device *netdev,
89 struct io_buffer *iobuf ) {
90 struct vlan_device *vlan = netdev->priv;
91 struct net_device *trunk = vlan->trunk;
92 struct ll_protocol *ll_protocol;
93 struct vlan_header *vlanhdr;
94 uint8_t ll_dest_copy[ETH_ALEN];
95 uint8_t ll_source_copy[ETH_ALEN];
96 const void *ll_dest;
97 const void *ll_source;
98 uint16_t net_proto;
99 unsigned int flags;
100 int rc;
101
102 /* Strip link-layer header and preserve link-layer header fields */
103 ll_protocol = netdev->ll_protocol;
104 if ( ( rc = ll_protocol->pull ( netdev, iobuf, &ll_dest, &ll_source,
105 &net_proto, &flags ) ) != 0 ) {
106 DBGC ( netdev, "VLAN %s could not parse link-layer header: "
107 "%s\n", netdev->name, strerror ( rc ) );
108 return rc;
109 }
110 memcpy ( ll_dest_copy, ll_dest, ETH_ALEN );
111 memcpy ( ll_source_copy, ll_source, ETH_ALEN );
112
113 /* Construct VLAN header */
114 vlanhdr = iob_push ( iobuf, sizeof ( *vlanhdr ) );
115 vlanhdr->tci = htons ( VLAN_TCI ( vlan->tag, vlan->priority ) );
116 vlanhdr->net_proto = net_proto;
117
118 /* Reclaim I/O buffer from VLAN device's TX queue */
119 list_del ( &iobuf->list );
120
121 /* Transmit packet on trunk device */
122 if ( ( rc = net_tx ( iob_disown ( iobuf ), trunk, &vlan_protocol,
123 ll_dest_copy, ll_source_copy ) ) != 0 ) {
124 DBGC ( netdev, "VLAN %s could not transmit: %s\n",
125 netdev->name, strerror ( rc ) );
126 /* Cannot return an error status, since that would
127 * cause the I/O buffer to be double-freed.
128 */
129 return 0;
130 }
131
132 return 0;
133 }
134
135 /**
136 * Poll VLAN device
137 *
138 * @v netdev Network device
139 */
vlan_poll(struct net_device * netdev)140 static void vlan_poll ( struct net_device *netdev ) {
141 struct vlan_device *vlan = netdev->priv;
142
143 /* Poll trunk device */
144 netdev_poll ( vlan->trunk );
145 }
146
147 /**
148 * Enable/disable interrupts on VLAN device
149 *
150 * @v netdev Network device
151 * @v enable Interrupts should be enabled
152 */
vlan_irq(struct net_device * netdev,int enable)153 static void vlan_irq ( struct net_device *netdev, int enable ) {
154 struct vlan_device *vlan = netdev->priv;
155
156 /* Enable/disable interrupts on trunk device. This is not at
157 * all robust, but there is no sensible course of action
158 * available.
159 */
160 netdev_irq ( vlan->trunk, enable );
161 }
162
163 /** VLAN device operations */
164 static struct net_device_operations vlan_operations = {
165 .open = vlan_open,
166 .close = vlan_close,
167 .transmit = vlan_transmit,
168 .poll = vlan_poll,
169 .irq = vlan_irq,
170 };
171
172 /**
173 * Synchronise VLAN device
174 *
175 * @v netdev Network device
176 */
vlan_sync(struct net_device * netdev)177 static void vlan_sync ( struct net_device *netdev ) {
178 struct vlan_device *vlan = netdev->priv;
179 struct net_device *trunk = vlan->trunk;
180
181 /* Synchronise link status */
182 if ( netdev->link_rc != trunk->link_rc )
183 netdev_link_err ( netdev, trunk->link_rc );
184
185 /* Synchronise open/closed status */
186 if ( netdev_is_open ( trunk ) ) {
187 if ( ! netdev_is_open ( netdev ) )
188 netdev_open ( netdev );
189 } else {
190 if ( netdev_is_open ( netdev ) )
191 netdev_close ( netdev );
192 }
193 }
194
195 /**
196 * Identify VLAN device
197 *
198 * @v trunk Trunk network device
199 * @v tag VLAN tag
200 * @ret netdev VLAN device, if any
201 */
vlan_find(struct net_device * trunk,unsigned int tag)202 struct net_device * vlan_find ( struct net_device *trunk, unsigned int tag ) {
203 struct net_device *netdev;
204 struct vlan_device *vlan;
205
206 for_each_netdev ( netdev ) {
207 if ( netdev->op != &vlan_operations )
208 continue;
209 vlan = netdev->priv;
210 if ( ( vlan->trunk == trunk ) && ( vlan->tag == tag ) )
211 return netdev;
212 }
213 return NULL;
214 }
215
216 /**
217 * Process incoming VLAN packet
218 *
219 * @v iobuf I/O buffer
220 * @v trunk Trunk network device
221 * @v ll_dest Link-layer destination address
222 * @v ll_source Link-layer source address
223 * @v flags Packet flags
224 * @ret rc Return status code
225 */
vlan_rx(struct io_buffer * iobuf,struct net_device * trunk,const void * ll_dest,const void * ll_source,unsigned int flags __unused)226 static int vlan_rx ( struct io_buffer *iobuf, struct net_device *trunk,
227 const void *ll_dest, const void *ll_source,
228 unsigned int flags __unused ) {
229 struct vlan_header *vlanhdr = iobuf->data;
230 struct net_device *netdev;
231 struct ll_protocol *ll_protocol;
232 uint8_t ll_dest_copy[ETH_ALEN];
233 uint8_t ll_source_copy[ETH_ALEN];
234 uint16_t tag;
235 int rc;
236
237 /* Sanity check */
238 if ( iob_len ( iobuf ) < sizeof ( *vlanhdr ) ) {
239 DBGC ( trunk, "VLAN %s received underlength packet (%zd "
240 "bytes)\n", trunk->name, iob_len ( iobuf ) );
241 rc = -EINVAL;
242 goto err_sanity;
243 }
244
245 /* Identify VLAN device */
246 tag = VLAN_TAG ( ntohs ( vlanhdr->tci ) );
247 netdev = vlan_find ( trunk, tag );
248 if ( ! netdev ) {
249 DBGC2 ( trunk, "VLAN %s received packet for unknown VLAN "
250 "%d\n", trunk->name, tag );
251 rc = -EPIPE;
252 goto err_no_vlan;
253 }
254
255 /* Strip VLAN header and preserve original link-layer header fields */
256 iob_pull ( iobuf, sizeof ( *vlanhdr ) );
257 ll_protocol = trunk->ll_protocol;
258 memcpy ( ll_dest_copy, ll_dest, ETH_ALEN );
259 memcpy ( ll_source_copy, ll_source, ETH_ALEN );
260
261 /* Reconstruct link-layer header for VLAN device */
262 ll_protocol = netdev->ll_protocol;
263 if ( ( rc = ll_protocol->push ( netdev, iobuf, ll_dest_copy,
264 ll_source_copy,
265 vlanhdr->net_proto ) ) != 0 ) {
266 DBGC ( netdev, "VLAN %s could not reconstruct link-layer "
267 "header: %s\n", netdev->name, strerror ( rc ) );
268 goto err_ll_push;
269 }
270
271 /* Enqueue packet on VLAN device */
272 netdev_rx ( netdev, iob_disown ( iobuf ) );
273 return 0;
274
275 err_ll_push:
276 err_no_vlan:
277 err_sanity:
278 free_iob ( iobuf );
279 return rc;
280 }
281
282 /** VLAN protocol */
283 struct net_protocol vlan_protocol __net_protocol = {
284 .name = "VLAN",
285 .net_proto = htons ( ETH_P_8021Q ),
286 .rx = vlan_rx,
287 };
288
289 /**
290 * Get the VLAN tag
291 *
292 * @v netdev Network device
293 * @ret tag VLAN tag, or 0 if device is not a VLAN device
294 */
vlan_tag(struct net_device * netdev)295 unsigned int vlan_tag ( struct net_device *netdev ) {
296 struct vlan_device *vlan;
297
298 if ( netdev->op == &vlan_operations ) {
299 vlan = netdev->priv;
300 return vlan->tag;
301 } else {
302 return 0;
303 }
304 }
305
306 /**
307 * Check if network device can be used as a VLAN trunk device
308 *
309 * @v trunk Trunk network device
310 * @ret is_ok Trunk network device is usable
311 *
312 * VLAN devices will be created as Ethernet devices. (We cannot
313 * simply clone the link layer of the trunk network device, because
314 * this link layer may expect the network device structure to contain
315 * some link-layer-private data.) The trunk network device must
316 * therefore have a link layer that is in some sense 'compatible' with
317 * Ethernet; specifically, it must have link-layer addresses that are
318 * the same length as Ethernet link-layer addresses.
319 *
320 * As an additional check, and primarily to assist with the sanity of
321 * the FCoE code, we refuse to allow nested VLANs.
322 */
vlan_can_be_trunk(struct net_device * trunk)323 int vlan_can_be_trunk ( struct net_device *trunk ) {
324
325 return ( ( trunk->ll_protocol->ll_addr_len == ETH_ALEN ) &&
326 ( trunk->op != &vlan_operations ) );
327 }
328
329 /**
330 * Create VLAN device
331 *
332 * @v trunk Trunk network device
333 * @v tag VLAN tag
334 * @v priority Default VLAN priority
335 * @ret rc Return status code
336 */
vlan_create(struct net_device * trunk,unsigned int tag,unsigned int priority)337 int vlan_create ( struct net_device *trunk, unsigned int tag,
338 unsigned int priority ) {
339 struct net_device *netdev;
340 struct vlan_device *vlan;
341 int rc;
342
343 /* If VLAN already exists, just update the priority */
344 if ( ( netdev = vlan_find ( trunk, tag ) ) != NULL ) {
345 vlan = netdev->priv;
346 if ( priority != vlan->priority ) {
347 DBGC ( netdev, "VLAN %s priority changed from %d to "
348 "%d\n", netdev->name, vlan->priority, priority );
349 }
350 vlan->priority = priority;
351 return 0;
352 }
353
354 /* Sanity checks */
355 if ( ! vlan_can_be_trunk ( trunk ) ) {
356 DBGC ( trunk, "VLAN %s cannot create VLAN on non-trunk "
357 "device\n", trunk->name );
358 rc = -ENOTTY;
359 goto err_sanity;
360 }
361 if ( ! VLAN_TAG_IS_VALID ( tag ) ) {
362 DBGC ( trunk, "VLAN %s cannot create VLAN with invalid tag "
363 "%d\n", trunk->name, tag );
364 rc = -EINVAL;
365 goto err_sanity;
366 }
367 if ( ! VLAN_PRIORITY_IS_VALID ( priority ) ) {
368 DBGC ( trunk, "VLAN %s cannot create VLAN with invalid "
369 "priority %d\n", trunk->name, priority );
370 rc = -EINVAL;
371 goto err_sanity;
372 }
373
374 /* Allocate and initialise structure */
375 netdev = alloc_etherdev ( sizeof ( *vlan ) );
376 if ( ! netdev ) {
377 rc = -ENOMEM;
378 goto err_alloc_etherdev;
379 }
380 netdev_init ( netdev, &vlan_operations );
381 netdev->dev = trunk->dev;
382 memcpy ( netdev->hw_addr, trunk->ll_addr, ETH_ALEN );
383 vlan = netdev->priv;
384 vlan->trunk = netdev_get ( trunk );
385 vlan->tag = tag;
386 vlan->priority = priority;
387
388 /* Construct VLAN device name */
389 snprintf ( netdev->name, sizeof ( netdev->name ), "%s-%d",
390 trunk->name, vlan->tag );
391
392 /* Mark device as not supporting interrupts, if applicable */
393 if ( ! netdev_irq_supported ( trunk ) )
394 netdev->state |= NETDEV_IRQ_UNSUPPORTED;
395
396 /* Register VLAN device */
397 if ( ( rc = register_netdev ( netdev ) ) != 0 ) {
398 DBGC ( netdev, "VLAN %s could not register: %s\n",
399 netdev->name, strerror ( rc ) );
400 goto err_register;
401 }
402
403 /* Synchronise with trunk device */
404 vlan_sync ( netdev );
405
406 DBGC ( netdev, "VLAN %s created with tag %d and priority %d\n",
407 netdev->name, vlan->tag, vlan->priority );
408
409 return 0;
410
411 unregister_netdev ( netdev );
412 err_register:
413 netdev_nullify ( netdev );
414 netdev_put ( netdev );
415 netdev_put ( trunk );
416 err_alloc_etherdev:
417 err_sanity:
418 return rc;
419 }
420
421 /**
422 * Destroy VLAN device
423 *
424 * @v netdev Network device
425 * @ret rc Return status code
426 */
vlan_destroy(struct net_device * netdev)427 int vlan_destroy ( struct net_device *netdev ) {
428 struct vlan_device *vlan = netdev->priv;
429 struct net_device *trunk;
430
431 /* Sanity check */
432 if ( netdev->op != &vlan_operations ) {
433 DBGC ( netdev, "VLAN %s cannot destroy non-VLAN device\n",
434 netdev->name );
435 return -ENOTTY;
436 }
437
438 DBGC ( netdev, "VLAN %s destroyed\n", netdev->name );
439
440 /* Remove VLAN device */
441 unregister_netdev ( netdev );
442 trunk = vlan->trunk;
443 netdev_nullify ( netdev );
444 netdev_put ( netdev );
445 netdev_put ( trunk );
446
447 return 0;
448 }
449
450 /**
451 * Handle trunk network device link state change
452 *
453 * @v trunk Trunk network device
454 */
vlan_notify(struct net_device * trunk)455 static void vlan_notify ( struct net_device *trunk ) {
456 struct net_device *netdev;
457 struct vlan_device *vlan;
458
459 for_each_netdev ( netdev ) {
460 if ( netdev->op != &vlan_operations )
461 continue;
462 vlan = netdev->priv;
463 if ( vlan->trunk == trunk )
464 vlan_sync ( netdev );
465 }
466 }
467
468 /**
469 * Destroy first VLAN device for a given trunk
470 *
471 * @v trunk Trunk network device
472 * @ret found A VLAN device was found
473 */
vlan_remove_first(struct net_device * trunk)474 static int vlan_remove_first ( struct net_device *trunk ) {
475 struct net_device *netdev;
476 struct vlan_device *vlan;
477
478 for_each_netdev ( netdev ) {
479 if ( netdev->op != &vlan_operations )
480 continue;
481 vlan = netdev->priv;
482 if ( vlan->trunk == trunk ) {
483 vlan_destroy ( netdev );
484 return 1;
485 }
486 }
487 return 0;
488 }
489
490 /**
491 * Destroy all VLAN devices for a given trunk
492 *
493 * @v trunk Trunk network device
494 */
vlan_remove(struct net_device * trunk)495 static void vlan_remove ( struct net_device *trunk ) {
496
497 /* Remove all VLAN devices attached to this trunk, safe
498 * against arbitrary net device removal.
499 */
500 while ( vlan_remove_first ( trunk ) ) {}
501 }
502
503 /** VLAN driver */
504 struct net_driver vlan_driver __net_driver = {
505 .name = "VLAN",
506 .notify = vlan_notify,
507 .remove = vlan_remove,
508 };
509