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8#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
9
10#include <linux/fs.h>
11#include <linux/hardirq.h>
12#include <linux/init.h>
13#include <linux/module.h>
14#include <linux/netdevice.h>
15#include <linux/if_ether.h>
16#include <linux/moduleparam.h>
17#include <linux/ip.h>
18#include <linux/sched.h>
19#include <linux/sockios.h>
20#include <linux/caif/if_caif.h>
21#include <net/rtnetlink.h>
22#include <net/caif/caif_layer.h>
23#include <net/caif/cfpkt.h>
24#include <net/caif/caif_dev.h>
25
26
27#define GPRS_PDP_MTU 1500
28
29#define CONNECT_TIMEOUT (5 * HZ)
30#define CAIF_NET_DEFAULT_QUEUE_LEN 500
31#define UNDEF_CONNID 0xffffffff
32
33
34static LIST_HEAD(chnl_net_list);
35
36MODULE_LICENSE("GPL");
37MODULE_ALIAS_RTNL_LINK("caif");
38
39enum caif_states {
40 CAIF_CONNECTED = 1,
41 CAIF_CONNECTING,
42 CAIF_DISCONNECTED,
43 CAIF_SHUTDOWN
44};
45
46struct chnl_net {
47 struct cflayer chnl;
48 struct net_device_stats stats;
49 struct caif_connect_request conn_req;
50 struct list_head list_field;
51 struct net_device *netdev;
52 char name[256];
53 wait_queue_head_t netmgmt_wq;
54
55 bool flowenabled;
56 enum caif_states state;
57};
58
59static void robust_list_del(struct list_head *delete_node)
60{
61 struct list_head *list_node;
62 struct list_head *n;
63 ASSERT_RTNL();
64 list_for_each_safe(list_node, n, &chnl_net_list) {
65 if (list_node == delete_node) {
66 list_del(list_node);
67 return;
68 }
69 }
70 WARN_ON(1);
71}
72
73static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
74{
75 struct sk_buff *skb;
76 struct chnl_net *priv;
77 int pktlen;
78 const u8 *ip_version;
79 u8 buf;
80
81 priv = container_of(layr, struct chnl_net, chnl);
82 if (!priv)
83 return -EINVAL;
84
85 skb = (struct sk_buff *) cfpkt_tonative(pkt);
86
87
88 pktlen = skb->len;
89
90
91
92
93 skb->dev = priv->netdev;
94
95
96 ip_version = skb_header_pointer(skb, 0, 1, &buf);
97 if (!ip_version) {
98 kfree_skb(skb);
99 return -EINVAL;
100 }
101
102 switch (*ip_version >> 4) {
103 case 4:
104 skb->protocol = htons(ETH_P_IP);
105 break;
106 case 6:
107 skb->protocol = htons(ETH_P_IPV6);
108 break;
109 default:
110 kfree_skb(skb);
111 priv->netdev->stats.rx_errors++;
112 return -EINVAL;
113 }
114
115
116 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
117 skb->ip_summed = CHECKSUM_UNNECESSARY;
118 else
119 skb->ip_summed = CHECKSUM_NONE;
120
121 if (in_interrupt())
122 netif_rx(skb);
123 else
124 netif_rx_ni(skb);
125
126
127 priv->netdev->stats.rx_packets++;
128 priv->netdev->stats.rx_bytes += pktlen;
129
130 return 0;
131}
132
133static int delete_device(struct chnl_net *dev)
134{
135 ASSERT_RTNL();
136 if (dev->netdev)
137 unregister_netdevice(dev->netdev);
138 return 0;
139}
140
141static void close_work(struct work_struct *work)
142{
143 struct chnl_net *dev = NULL;
144 struct list_head *list_node;
145 struct list_head *_tmp;
146
147 rtnl_lock();
148 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
149 dev = list_entry(list_node, struct chnl_net, list_field);
150 if (dev->state == CAIF_SHUTDOWN)
151 dev_close(dev->netdev);
152 }
153 rtnl_unlock();
154}
155static DECLARE_WORK(close_worker, close_work);
156
157static void chnl_hold(struct cflayer *lyr)
158{
159 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
160 dev_hold(priv->netdev);
161}
162
163static void chnl_put(struct cflayer *lyr)
164{
165 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
166 dev_put(priv->netdev);
167}
168
169static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
170 int phyid)
171{
172 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
173 pr_debug("NET flowctrl func called flow: %s\n",
174 flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
175 flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
176 flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
177 flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
178 flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
179 flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
180 "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");
181
182
183
184 switch (flow) {
185 case CAIF_CTRLCMD_FLOW_OFF_IND:
186 priv->flowenabled = false;
187 netif_stop_queue(priv->netdev);
188 break;
189 case CAIF_CTRLCMD_DEINIT_RSP:
190 priv->state = CAIF_DISCONNECTED;
191 break;
192 case CAIF_CTRLCMD_INIT_FAIL_RSP:
193 priv->state = CAIF_DISCONNECTED;
194 wake_up_interruptible(&priv->netmgmt_wq);
195 break;
196 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
197 priv->state = CAIF_SHUTDOWN;
198 netif_tx_disable(priv->netdev);
199 schedule_work(&close_worker);
200 break;
201 case CAIF_CTRLCMD_FLOW_ON_IND:
202 priv->flowenabled = true;
203 netif_wake_queue(priv->netdev);
204 break;
205 case CAIF_CTRLCMD_INIT_RSP:
206 caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
207 priv->state = CAIF_CONNECTED;
208 priv->flowenabled = true;
209 netif_wake_queue(priv->netdev);
210 wake_up_interruptible(&priv->netmgmt_wq);
211 break;
212 default:
213 break;
214 }
215}
216
217static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
218{
219 struct chnl_net *priv;
220 struct cfpkt *pkt = NULL;
221 int len;
222 int result = -1;
223
224 priv = netdev_priv(dev);
225
226 if (skb->len > priv->netdev->mtu) {
227 pr_warn("Size of skb exceeded MTU\n");
228 kfree_skb(skb);
229 dev->stats.tx_errors++;
230 return NETDEV_TX_OK;
231 }
232
233 if (!priv->flowenabled) {
234 pr_debug("dropping packets flow off\n");
235 kfree_skb(skb);
236 dev->stats.tx_dropped++;
237 return NETDEV_TX_OK;
238 }
239
240 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
241 swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
242
243
244 len = skb->len;
245
246 pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
247
248
249 result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
250 if (result) {
251 dev->stats.tx_dropped++;
252 return NETDEV_TX_OK;
253 }
254
255
256 dev->stats.tx_packets++;
257 dev->stats.tx_bytes += len;
258
259 return NETDEV_TX_OK;
260}
261
262static int chnl_net_open(struct net_device *dev)
263{
264 struct chnl_net *priv = NULL;
265 int result = -1;
266 int llifindex, headroom, tailroom, mtu;
267 struct net_device *lldev;
268 ASSERT_RTNL();
269 priv = netdev_priv(dev);
270 if (!priv) {
271 pr_debug("chnl_net_open: no priv\n");
272 return -ENODEV;
273 }
274
275 if (priv->state != CAIF_CONNECTING) {
276 priv->state = CAIF_CONNECTING;
277 result = caif_connect_client(dev_net(dev), &priv->conn_req,
278 &priv->chnl, &llifindex,
279 &headroom, &tailroom);
280 if (result != 0) {
281 pr_debug("err: "
282 "Unable to register and open device,"
283 " Err:%d\n",
284 result);
285 goto error;
286 }
287
288 lldev = __dev_get_by_index(dev_net(dev), llifindex);
289
290 if (lldev == NULL) {
291 pr_debug("no interface?\n");
292 result = -ENODEV;
293 goto error;
294 }
295
296 dev->needed_tailroom = tailroom + lldev->needed_tailroom;
297 dev->hard_header_len = headroom + lldev->hard_header_len +
298 lldev->needed_tailroom;
299
300
301
302
303
304
305
306
307 mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
308 mtu = min_t(int, GPRS_PDP_MTU, mtu);
309 dev_set_mtu(dev, mtu);
310
311 if (mtu < 100) {
312 pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
313 result = -ENODEV;
314 goto error;
315 }
316 }
317
318 rtnl_unlock();
319
320 result = wait_event_interruptible_timeout(priv->netmgmt_wq,
321 priv->state != CAIF_CONNECTING,
322 CONNECT_TIMEOUT);
323
324 rtnl_lock();
325
326 if (result == -ERESTARTSYS) {
327 pr_debug("wait_event_interruptible woken by a signal\n");
328 result = -ERESTARTSYS;
329 goto error;
330 }
331
332 if (result == 0) {
333 pr_debug("connect timeout\n");
334 caif_disconnect_client(dev_net(dev), &priv->chnl);
335 priv->state = CAIF_DISCONNECTED;
336 pr_debug("state disconnected\n");
337 result = -ETIMEDOUT;
338 goto error;
339 }
340
341 if (priv->state != CAIF_CONNECTED) {
342 pr_debug("connect failed\n");
343 result = -ECONNREFUSED;
344 goto error;
345 }
346 pr_debug("CAIF Netdevice connected\n");
347 return 0;
348
349error:
350 caif_disconnect_client(dev_net(dev), &priv->chnl);
351 priv->state = CAIF_DISCONNECTED;
352 pr_debug("state disconnected\n");
353 return result;
354
355}
356
357static int chnl_net_stop(struct net_device *dev)
358{
359 struct chnl_net *priv;
360
361 ASSERT_RTNL();
362 priv = netdev_priv(dev);
363 priv->state = CAIF_DISCONNECTED;
364 caif_disconnect_client(dev_net(dev), &priv->chnl);
365 return 0;
366}
367
368static int chnl_net_init(struct net_device *dev)
369{
370 struct chnl_net *priv;
371 ASSERT_RTNL();
372 priv = netdev_priv(dev);
373 strncpy(priv->name, dev->name, sizeof(priv->name));
374 return 0;
375}
376
377static void chnl_net_uninit(struct net_device *dev)
378{
379 struct chnl_net *priv;
380 ASSERT_RTNL();
381 priv = netdev_priv(dev);
382 robust_list_del(&priv->list_field);
383}
384
385static const struct net_device_ops netdev_ops = {
386 .ndo_open = chnl_net_open,
387 .ndo_stop = chnl_net_stop,
388 .ndo_init = chnl_net_init,
389 .ndo_uninit = chnl_net_uninit,
390 .ndo_start_xmit = chnl_net_start_xmit,
391};
392
393static void chnl_net_destructor(struct net_device *dev)
394{
395 struct chnl_net *priv = netdev_priv(dev);
396 caif_free_client(&priv->chnl);
397 free_netdev(dev);
398}
399
400static void ipcaif_net_setup(struct net_device *dev)
401{
402 struct chnl_net *priv;
403 dev->netdev_ops = &netdev_ops;
404 dev->destructor = chnl_net_destructor;
405 dev->flags |= IFF_NOARP;
406 dev->flags |= IFF_POINTOPOINT;
407 dev->mtu = GPRS_PDP_MTU;
408 dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
409
410 priv = netdev_priv(dev);
411 priv->chnl.receive = chnl_recv_cb;
412 priv->chnl.ctrlcmd = chnl_flowctrl_cb;
413 priv->netdev = dev;
414 priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
415 priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
416 priv->conn_req.priority = CAIF_PRIO_LOW;
417
418 priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
419 priv->flowenabled = false;
420
421 init_waitqueue_head(&priv->netmgmt_wq);
422}
423
424
425static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
426{
427 struct chnl_net *priv;
428 u8 loop;
429 priv = netdev_priv(dev);
430 if (nla_put_u32(skb, IFLA_CAIF_IPV4_CONNID,
431 priv->conn_req.sockaddr.u.dgm.connection_id) ||
432 nla_put_u32(skb, IFLA_CAIF_IPV6_CONNID,
433 priv->conn_req.sockaddr.u.dgm.connection_id))
434 goto nla_put_failure;
435 loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
436 if (nla_put_u8(skb, IFLA_CAIF_LOOPBACK, loop))
437 goto nla_put_failure;
438 return 0;
439nla_put_failure:
440 return -EMSGSIZE;
441
442}
443
444static void caif_netlink_parms(struct nlattr *data[],
445 struct caif_connect_request *conn_req)
446{
447 if (!data) {
448 pr_warn("no params data found\n");
449 return;
450 }
451 if (data[IFLA_CAIF_IPV4_CONNID])
452 conn_req->sockaddr.u.dgm.connection_id =
453 nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
454 if (data[IFLA_CAIF_IPV6_CONNID])
455 conn_req->sockaddr.u.dgm.connection_id =
456 nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
457 if (data[IFLA_CAIF_LOOPBACK]) {
458 if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
459 conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
460 else
461 conn_req->protocol = CAIFPROTO_DATAGRAM;
462 }
463}
464
465static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
466 struct nlattr *tb[], struct nlattr *data[])
467{
468 int ret;
469 struct chnl_net *caifdev;
470 ASSERT_RTNL();
471 caifdev = netdev_priv(dev);
472 caif_netlink_parms(data, &caifdev->conn_req);
473 dev_net_set(caifdev->netdev, src_net);
474
475 ret = register_netdevice(dev);
476 if (ret)
477 pr_warn("device rtml registration failed\n");
478 else
479 list_add(&caifdev->list_field, &chnl_net_list);
480
481
482 if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
483 caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
484 caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
485 }
486 return ret;
487}
488
489static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
490 struct nlattr *data[])
491{
492 struct chnl_net *caifdev;
493 ASSERT_RTNL();
494 caifdev = netdev_priv(dev);
495 caif_netlink_parms(data, &caifdev->conn_req);
496 netdev_state_change(dev);
497 return 0;
498}
499
500static size_t ipcaif_get_size(const struct net_device *dev)
501{
502 return
503
504 nla_total_size(4) +
505
506 nla_total_size(4) +
507
508 nla_total_size(2) +
509 0;
510}
511
512static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
513 [IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
514 [IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
515 [IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
516};
517
518
519static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
520 .kind = "caif",
521 .priv_size = sizeof(struct chnl_net),
522 .setup = ipcaif_net_setup,
523 .maxtype = IFLA_CAIF_MAX,
524 .policy = ipcaif_policy,
525 .newlink = ipcaif_newlink,
526 .changelink = ipcaif_changelink,
527 .get_size = ipcaif_get_size,
528 .fill_info = ipcaif_fill_info,
529
530};
531
532static int __init chnl_init_module(void)
533{
534 return rtnl_link_register(&ipcaif_link_ops);
535}
536
537static void __exit chnl_exit_module(void)
538{
539 struct chnl_net *dev = NULL;
540 struct list_head *list_node;
541 struct list_head *_tmp;
542 rtnl_link_unregister(&ipcaif_link_ops);
543 rtnl_lock();
544 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
545 dev = list_entry(list_node, struct chnl_net, list_field);
546 list_del(list_node);
547 delete_device(dev);
548 }
549 rtnl_unlock();
550}
551
552module_init(chnl_init_module);
553module_exit(chnl_exit_module);
554
