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