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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
98 switch (*ip_version >> 4) {
99 case 4:
100 skb->protocol = htons(ETH_P_IP);
101 break;
102 case 6:
103 skb->protocol = htons(ETH_P_IPV6);
104 break;
105 default:
106 kfree_skb(skb);
107 priv->netdev->stats.rx_errors++;
108 return -EINVAL;
109 }
110
111
112 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
113 skb->ip_summed = CHECKSUM_UNNECESSARY;
114 else
115 skb->ip_summed = CHECKSUM_NONE;
116
117 if (in_interrupt())
118 netif_rx(skb);
119 else
120 netif_rx_ni(skb);
121
122
123 priv->netdev->stats.rx_packets++;
124 priv->netdev->stats.rx_bytes += pktlen;
125
126 return 0;
127}
128
129static int delete_device(struct chnl_net *dev)
130{
131 ASSERT_RTNL();
132 if (dev->netdev)
133 unregister_netdevice(dev->netdev);
134 return 0;
135}
136
137static void close_work(struct work_struct *work)
138{
139 struct chnl_net *dev = NULL;
140 struct list_head *list_node;
141 struct list_head *_tmp;
142
143 rtnl_lock();
144 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
145 dev = list_entry(list_node, struct chnl_net, list_field);
146 if (dev->state == CAIF_SHUTDOWN)
147 dev_close(dev->netdev);
148 }
149 rtnl_unlock();
150}
151static DECLARE_WORK(close_worker, close_work);
152
153static void chnl_hold(struct cflayer *lyr)
154{
155 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
156 dev_hold(priv->netdev);
157}
158
159static void chnl_put(struct cflayer *lyr)
160{
161 struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
162 dev_put(priv->netdev);
163}
164
165static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
166 int phyid)
167{
168 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
169 pr_debug("NET flowctrl func called flow: %s\n",
170 flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
171 flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
172 flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
173 flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
174 flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
175 flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
176 "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");
177
178
179
180 switch (flow) {
181 case CAIF_CTRLCMD_FLOW_OFF_IND:
182 priv->flowenabled = false;
183 netif_stop_queue(priv->netdev);
184 break;
185 case CAIF_CTRLCMD_DEINIT_RSP:
186 priv->state = CAIF_DISCONNECTED;
187 break;
188 case CAIF_CTRLCMD_INIT_FAIL_RSP:
189 priv->state = CAIF_DISCONNECTED;
190 wake_up_interruptible(&priv->netmgmt_wq);
191 break;
192 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
193 priv->state = CAIF_SHUTDOWN;
194 netif_tx_disable(priv->netdev);
195 schedule_work(&close_worker);
196 break;
197 case CAIF_CTRLCMD_FLOW_ON_IND:
198 priv->flowenabled = true;
199 netif_wake_queue(priv->netdev);
200 break;
201 case CAIF_CTRLCMD_INIT_RSP:
202 caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
203 priv->state = CAIF_CONNECTED;
204 priv->flowenabled = true;
205 netif_wake_queue(priv->netdev);
206 wake_up_interruptible(&priv->netmgmt_wq);
207 break;
208 default:
209 break;
210 }
211}
212
213static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
214{
215 struct chnl_net *priv;
216 struct cfpkt *pkt = NULL;
217 int len;
218 int result = -1;
219
220 priv = netdev_priv(dev);
221
222 if (skb->len > priv->netdev->mtu) {
223 pr_warn("Size of skb exceeded MTU\n");
224 kfree_skb(skb);
225 dev->stats.tx_errors++;
226 return NETDEV_TX_OK;
227 }
228
229 if (!priv->flowenabled) {
230 pr_debug("dropping packets flow off\n");
231 kfree_skb(skb);
232 dev->stats.tx_dropped++;
233 return NETDEV_TX_OK;
234 }
235
236 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
237 swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
238
239
240 len = skb->len;
241
242 pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
243
244
245 result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
246 if (result) {
247 dev->stats.tx_dropped++;
248 return NETDEV_TX_OK;
249 }
250
251
252 dev->stats.tx_packets++;
253 dev->stats.tx_bytes += len;
254
255 return NETDEV_TX_OK;
256}
257
258static int chnl_net_open(struct net_device *dev)
259{
260 struct chnl_net *priv = NULL;
261 int result = -1;
262 int llifindex, headroom, tailroom, mtu;
263 struct net_device *lldev;
264 ASSERT_RTNL();
265 priv = netdev_priv(dev);
266 if (!priv) {
267 pr_debug("chnl_net_open: no priv\n");
268 return -ENODEV;
269 }
270
271 if (priv->state != CAIF_CONNECTING) {
272 priv->state = CAIF_CONNECTING;
273 result = caif_connect_client(dev_net(dev), &priv->conn_req,
274 &priv->chnl, &llifindex,
275 &headroom, &tailroom);
276 if (result != 0) {
277 pr_debug("err: "
278 "Unable to register and open device,"
279 " Err:%d\n",
280 result);
281 goto error;
282 }
283
284 lldev = dev_get_by_index(dev_net(dev), llifindex);
285
286 if (lldev == NULL) {
287 pr_debug("no interface?\n");
288 result = -ENODEV;
289 goto error;
290 }
291
292 dev->needed_tailroom = tailroom + lldev->needed_tailroom;
293 dev->hard_header_len = headroom + lldev->hard_header_len +
294 lldev->needed_tailroom;
295
296
297
298
299
300
301
302
303 mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
304 mtu = min_t(int, GPRS_PDP_MTU, mtu);
305 dev_set_mtu(dev, mtu);
306 dev_put(lldev);
307
308 if (mtu < 100) {
309 pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
310 result = -ENODEV;
311 goto error;
312 }
313 }
314
315 rtnl_unlock();
316
317 result = wait_event_interruptible_timeout(priv->netmgmt_wq,
318 priv->state != CAIF_CONNECTING,
319 CONNECT_TIMEOUT);
320
321 rtnl_lock();
322
323 if (result == -ERESTARTSYS) {
324 pr_debug("wait_event_interruptible woken by a signal\n");
325 result = -ERESTARTSYS;
326 goto error;
327 }
328
329 if (result == 0) {
330 pr_debug("connect timeout\n");
331 caif_disconnect_client(dev_net(dev), &priv->chnl);
332 priv->state = CAIF_DISCONNECTED;
333 pr_debug("state disconnected\n");
334 result = -ETIMEDOUT;
335 goto error;
336 }
337
338 if (priv->state != CAIF_CONNECTED) {
339 pr_debug("connect failed\n");
340 result = -ECONNREFUSED;
341 goto error;
342 }
343 pr_debug("CAIF Netdevice connected\n");
344 return 0;
345
346error:
347 caif_disconnect_client(dev_net(dev), &priv->chnl);
348 priv->state = CAIF_DISCONNECTED;
349 pr_debug("state disconnected\n");
350 return result;
351
352}
353
354static int chnl_net_stop(struct net_device *dev)
355{
356 struct chnl_net *priv;
357
358 ASSERT_RTNL();
359 priv = netdev_priv(dev);
360 priv->state = CAIF_DISCONNECTED;
361 caif_disconnect_client(dev_net(dev), &priv->chnl);
362 return 0;
363}
364
365static int chnl_net_init(struct net_device *dev)
366{
367 struct chnl_net *priv;
368 ASSERT_RTNL();
369 priv = netdev_priv(dev);
370 strncpy(priv->name, dev->name, sizeof(priv->name));
371 return 0;
372}
373
374static void chnl_net_uninit(struct net_device *dev)
375{
376 struct chnl_net *priv;
377 ASSERT_RTNL();
378 priv = netdev_priv(dev);
379 robust_list_del(&priv->list_field);
380}
381
382static const struct net_device_ops netdev_ops = {
383 .ndo_open = chnl_net_open,
384 .ndo_stop = chnl_net_stop,
385 .ndo_init = chnl_net_init,
386 .ndo_uninit = chnl_net_uninit,
387 .ndo_start_xmit = chnl_net_start_xmit,
388};
389
390static void chnl_net_destructor(struct net_device *dev)
391{
392 struct chnl_net *priv = netdev_priv(dev);
393 caif_free_client(&priv->chnl);
394 free_netdev(dev);
395}
396
397static void ipcaif_net_setup(struct net_device *dev)
398{
399 struct chnl_net *priv;
400 dev->netdev_ops = &netdev_ops;
401 dev->destructor = chnl_net_destructor;
402 dev->flags |= IFF_NOARP;
403 dev->flags |= IFF_POINTOPOINT;
404 dev->mtu = GPRS_PDP_MTU;
405 dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
406
407 priv = netdev_priv(dev);
408 priv->chnl.receive = chnl_recv_cb;
409 priv->chnl.ctrlcmd = chnl_flowctrl_cb;
410 priv->netdev = dev;
411 priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
412 priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
413 priv->conn_req.priority = CAIF_PRIO_LOW;
414
415 priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
416 priv->flowenabled = false;
417
418 init_waitqueue_head(&priv->netmgmt_wq);
419}
420
421
422static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
423{
424 struct chnl_net *priv;
425 u8 loop;
426 priv = netdev_priv(dev);
427 NLA_PUT_U32(skb, IFLA_CAIF_IPV4_CONNID,
428 priv->conn_req.sockaddr.u.dgm.connection_id);
429 NLA_PUT_U32(skb, IFLA_CAIF_IPV6_CONNID,
430 priv->conn_req.sockaddr.u.dgm.connection_id);
431 loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
432 NLA_PUT_U8(skb, IFLA_CAIF_LOOPBACK, loop);
433
434
435 return 0;
436nla_put_failure:
437 return -EMSGSIZE;
438
439}
440
441static void caif_netlink_parms(struct nlattr *data[],
442 struct caif_connect_request *conn_req)
443{
444 if (!data) {
445 pr_warn("no params data found\n");
446 return;
447 }
448 if (data[IFLA_CAIF_IPV4_CONNID])
449 conn_req->sockaddr.u.dgm.connection_id =
450 nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
451 if (data[IFLA_CAIF_IPV6_CONNID])
452 conn_req->sockaddr.u.dgm.connection_id =
453 nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
454 if (data[IFLA_CAIF_LOOPBACK]) {
455 if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
456 conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
457 else
458 conn_req->protocol = CAIFPROTO_DATAGRAM;
459 }
460}
461
462static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
463 struct nlattr *tb[], struct nlattr *data[])
464{
465 int ret;
466 struct chnl_net *caifdev;
467 ASSERT_RTNL();
468 caifdev = netdev_priv(dev);
469 caif_netlink_parms(data, &caifdev->conn_req);
470 dev_net_set(caifdev->netdev, src_net);
471
472 ret = register_netdevice(dev);
473 if (ret)
474 pr_warn("device rtml registration failed\n");
475 else
476 list_add(&caifdev->list_field, &chnl_net_list);
477
478
479 if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
480 caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
481 caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
482 }
483 return ret;
484}
485
486static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
487 struct nlattr *data[])
488{
489 struct chnl_net *caifdev;
490 ASSERT_RTNL();
491 caifdev = netdev_priv(dev);
492 caif_netlink_parms(data, &caifdev->conn_req);
493 netdev_state_change(dev);
494 return 0;
495}
496
497static size_t ipcaif_get_size(const struct net_device *dev)
498{
499 return
500
501 nla_total_size(4) +
502
503 nla_total_size(4) +
504
505 nla_total_size(2) +
506 0;
507}
508
509static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
510 [IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
511 [IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
512 [IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
513};
514
515
516static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
517 .kind = "caif",
518 .priv_size = sizeof(struct chnl_net),
519 .setup = ipcaif_net_setup,
520 .maxtype = IFLA_CAIF_MAX,
521 .policy = ipcaif_policy,
522 .newlink = ipcaif_newlink,
523 .changelink = ipcaif_changelink,
524 .get_size = ipcaif_get_size,
525 .fill_info = ipcaif_fill_info,
526
527};
528
529static int __init chnl_init_module(void)
530{
531 return rtnl_link_register(&ipcaif_link_ops);
532}
533
534static void __exit chnl_exit_module(void)
535{
536 struct chnl_net *dev = NULL;
537 struct list_head *list_node;
538 struct list_head *_tmp;
539 rtnl_link_unregister(&ipcaif_link_ops);
540 rtnl_lock();
541 list_for_each_safe(list_node, _tmp, &chnl_net_list) {
542 dev = list_entry(list_node, struct chnl_net, list_field);
543 list_del(list_node);
544 delete_device(dev);
545 }
546 rtnl_unlock();
547}
548
549module_init(chnl_init_module);
550module_exit(chnl_exit_module);
551
