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