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26#include <linux/kernel.h>
27#include <linux/module.h>
28#include <linux/slab.h>
29#include <asm/unaligned.h>
30#include <net/sock.h>
31
32#include <linux/if_phonet.h>
33#include <linux/phonet.h>
34#include <net/phonet/phonet.h>
35#include <net/phonet/pn_dev.h>
36
37
38static const struct phonet_protocol *proto_tab[PHONET_NPROTO] __read_mostly;
39
40static const struct phonet_protocol *phonet_proto_get(unsigned int protocol)
41{
42 const struct phonet_protocol *pp;
43
44 if (protocol >= PHONET_NPROTO)
45 return NULL;
46
47 rcu_read_lock();
48 pp = rcu_dereference(proto_tab[protocol]);
49 if (pp && !try_module_get(pp->prot->owner))
50 pp = NULL;
51 rcu_read_unlock();
52
53 return pp;
54}
55
56static inline void phonet_proto_put(const struct phonet_protocol *pp)
57{
58 module_put(pp->prot->owner);
59}
60
61
62
63static int pn_socket_create(struct net *net, struct socket *sock, int protocol,
64 int kern)
65{
66 struct sock *sk;
67 struct pn_sock *pn;
68 const struct phonet_protocol *pnp;
69 int err;
70
71 if (!capable(CAP_SYS_ADMIN))
72 return -EPERM;
73
74 if (protocol == 0) {
75
76 switch (sock->type) {
77 case SOCK_DGRAM:
78 protocol = PN_PROTO_PHONET;
79 break;
80 case SOCK_SEQPACKET:
81 protocol = PN_PROTO_PIPE;
82 break;
83 default:
84 return -EPROTONOSUPPORT;
85 }
86 }
87
88 pnp = phonet_proto_get(protocol);
89 if (pnp == NULL &&
90 request_module("net-pf-%d-proto-%d", PF_PHONET, protocol) == 0)
91 pnp = phonet_proto_get(protocol);
92
93 if (pnp == NULL)
94 return -EPROTONOSUPPORT;
95 if (sock->type != pnp->sock_type) {
96 err = -EPROTONOSUPPORT;
97 goto out;
98 }
99
100 sk = sk_alloc(net, PF_PHONET, GFP_KERNEL, pnp->prot, kern);
101 if (sk == NULL) {
102 err = -ENOMEM;
103 goto out;
104 }
105
106 sock_init_data(sock, sk);
107 sock->state = SS_UNCONNECTED;
108 sock->ops = pnp->ops;
109 sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
110 sk->sk_protocol = protocol;
111 pn = pn_sk(sk);
112 pn->sobject = 0;
113 pn->dobject = 0;
114 pn->resource = 0;
115 sk->sk_prot->init(sk);
116 err = 0;
117
118out:
119 phonet_proto_put(pnp);
120 return err;
121}
122
123static const struct net_proto_family phonet_proto_family = {
124 .family = PF_PHONET,
125 .create = pn_socket_create,
126 .owner = THIS_MODULE,
127};
128
129
130static int pn_header_create(struct sk_buff *skb, struct net_device *dev,
131 unsigned short type, const void *daddr,
132 const void *saddr, unsigned int len)
133{
134 u8 *media = skb_push(skb, 1);
135
136 if (type != ETH_P_PHONET)
137 return -1;
138
139 if (!saddr)
140 saddr = dev->dev_addr;
141 *media = *(const u8 *)saddr;
142 return 1;
143}
144
145static int pn_header_parse(const struct sk_buff *skb, unsigned char *haddr)
146{
147 const u8 *media = skb_mac_header(skb);
148 *haddr = *media;
149 return 1;
150}
151
152const struct header_ops phonet_header_ops = {
153 .create = pn_header_create,
154 .parse = pn_header_parse,
155};
156EXPORT_SYMBOL(phonet_header_ops);
157
158
159
160
161static int pn_send(struct sk_buff *skb, struct net_device *dev,
162 u16 dst, u16 src, u8 res, u8 irq)
163{
164 struct phonethdr *ph;
165 int err;
166
167 if (skb->len + 2 > 0xffff ||
168 skb->len + sizeof(struct phonethdr) > dev->mtu) {
169 err = -EMSGSIZE;
170 goto drop;
171 }
172
173
174 if (pn_addr(dst) == PNADDR_BROADCAST) {
175 err = -EOPNOTSUPP;
176 goto drop;
177 }
178
179 skb_reset_transport_header(skb);
180 WARN_ON(skb_headroom(skb) & 1);
181 skb_push(skb, sizeof(struct phonethdr));
182 skb_reset_network_header(skb);
183 ph = pn_hdr(skb);
184 ph->pn_rdev = pn_dev(dst);
185 ph->pn_sdev = pn_dev(src);
186 ph->pn_res = res;
187 ph->pn_length = __cpu_to_be16(skb->len + 2 - sizeof(*ph));
188 ph->pn_robj = pn_obj(dst);
189 ph->pn_sobj = pn_obj(src);
190
191 skb->protocol = htons(ETH_P_PHONET);
192 skb->priority = 0;
193 skb->dev = dev;
194
195 if (skb->pkt_type == PACKET_LOOPBACK) {
196 skb_reset_mac_header(skb);
197 skb_orphan(skb);
198 err = (irq ? netif_rx(skb) : netif_rx_ni(skb)) ? -ENOBUFS : 0;
199 } else {
200 err = dev_hard_header(skb, dev, ntohs(skb->protocol),
201 NULL, NULL, skb->len);
202 if (err < 0) {
203 err = -EHOSTUNREACH;
204 goto drop;
205 }
206 err = dev_queue_xmit(skb);
207 if (unlikely(err > 0))
208 err = net_xmit_errno(err);
209 }
210
211 return err;
212drop:
213 kfree_skb(skb);
214 return err;
215}
216
217static int pn_raw_send(const void *data, int len, struct net_device *dev,
218 u16 dst, u16 src, u8 res)
219{
220 struct sk_buff *skb = alloc_skb(MAX_PHONET_HEADER + len, GFP_ATOMIC);
221 if (skb == NULL)
222 return -ENOMEM;
223
224 if (phonet_address_lookup(dev_net(dev), pn_addr(dst)) == 0)
225 skb->pkt_type = PACKET_LOOPBACK;
226
227 skb_reserve(skb, MAX_PHONET_HEADER);
228 __skb_put(skb, len);
229 skb_copy_to_linear_data(skb, data, len);
230 return pn_send(skb, dev, dst, src, res, 1);
231}
232
233
234
235
236
237int pn_skb_send(struct sock *sk, struct sk_buff *skb,
238 const struct sockaddr_pn *target)
239{
240 struct net *net = sock_net(sk);
241 struct net_device *dev;
242 struct pn_sock *pn = pn_sk(sk);
243 int err;
244 u16 src, dst;
245 u8 daddr, saddr, res;
246
247 src = pn->sobject;
248 if (target != NULL) {
249 dst = pn_sockaddr_get_object(target);
250 res = pn_sockaddr_get_resource(target);
251 } else {
252 dst = pn->dobject;
253 res = pn->resource;
254 }
255 daddr = pn_addr(dst);
256
257 err = -EHOSTUNREACH;
258 if (sk->sk_bound_dev_if)
259 dev = dev_get_by_index(net, sk->sk_bound_dev_if);
260 else if (phonet_address_lookup(net, daddr) == 0) {
261 dev = phonet_device_get(net);
262 skb->pkt_type = PACKET_LOOPBACK;
263 } else if (dst == 0) {
264
265 struct sock *sk = pn_find_sock_by_res(net, res);
266 if (sk) {
267 sock_put(sk);
268 dev = phonet_device_get(net);
269 skb->pkt_type = PACKET_LOOPBACK;
270 } else
271 dev = phonet_route_output(net, daddr);
272 } else
273 dev = phonet_route_output(net, daddr);
274
275 if (!dev || !(dev->flags & IFF_UP))
276 goto drop;
277
278 saddr = phonet_address_get(dev, daddr);
279 if (saddr == PN_NO_ADDR)
280 goto drop;
281
282 if (!pn_addr(src))
283 src = pn_object(saddr, pn_obj(src));
284
285 err = pn_send(skb, dev, dst, src, res, 0);
286 dev_put(dev);
287 return err;
288
289drop:
290 kfree_skb(skb);
291 if (dev)
292 dev_put(dev);
293 return err;
294}
295EXPORT_SYMBOL(pn_skb_send);
296
297
298static inline int can_respond(struct sk_buff *skb)
299{
300 const struct phonethdr *ph;
301 const struct phonetmsg *pm;
302 u8 submsg_id;
303
304 if (!pskb_may_pull(skb, 3))
305 return 0;
306
307 ph = pn_hdr(skb);
308 if (ph->pn_res == PN_PREFIX && !pskb_may_pull(skb, 5))
309 return 0;
310 if (ph->pn_res == PN_COMMGR)
311 return 0;
312
313 ph = pn_hdr(skb);
314 pm = pn_msg(skb);
315 if (pm->pn_msg_id != PN_COMMON_MESSAGE)
316 return 1;
317 submsg_id = (ph->pn_res == PN_PREFIX)
318 ? pm->pn_e_submsg_id : pm->pn_submsg_id;
319 if (submsg_id != PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP &&
320 pm->pn_e_submsg_id != PN_COMM_SERVICE_NOT_IDENTIFIED_RESP)
321 return 1;
322 return 0;
323}
324
325static int send_obj_unreachable(struct sk_buff *rskb)
326{
327 const struct phonethdr *oph = pn_hdr(rskb);
328 const struct phonetmsg *opm = pn_msg(rskb);
329 struct phonetmsg resp;
330
331 memset(&resp, 0, sizeof(resp));
332 resp.pn_trans_id = opm->pn_trans_id;
333 resp.pn_msg_id = PN_COMMON_MESSAGE;
334 if (oph->pn_res == PN_PREFIX) {
335 resp.pn_e_res_id = opm->pn_e_res_id;
336 resp.pn_e_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP;
337 resp.pn_e_orig_msg_id = opm->pn_msg_id;
338 resp.pn_e_status = 0;
339 } else {
340 resp.pn_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP;
341 resp.pn_orig_msg_id = opm->pn_msg_id;
342 resp.pn_status = 0;
343 }
344 return pn_raw_send(&resp, sizeof(resp), rskb->dev,
345 pn_object(oph->pn_sdev, oph->pn_sobj),
346 pn_object(oph->pn_rdev, oph->pn_robj),
347 oph->pn_res);
348}
349
350static int send_reset_indications(struct sk_buff *rskb)
351{
352 struct phonethdr *oph = pn_hdr(rskb);
353 static const u8 data[4] = {
354 0x00 , 0x10 ,
355 0x00 , 0x00
356 };
357
358 return pn_raw_send(data, sizeof(data), rskb->dev,
359 pn_object(oph->pn_sdev, 0x00),
360 pn_object(oph->pn_rdev, oph->pn_robj),
361 PN_COMMGR);
362}
363
364
365
366
367
368
369
370
371static int phonet_rcv(struct sk_buff *skb, struct net_device *dev,
372 struct packet_type *pkttype,
373 struct net_device *orig_dev)
374{
375 struct net *net = dev_net(dev);
376 struct phonethdr *ph;
377 struct sockaddr_pn sa;
378 u16 len;
379
380 skb = skb_share_check(skb, GFP_ATOMIC);
381 if (!skb)
382 return NET_RX_DROP;
383
384
385 if (!pskb_pull(skb, sizeof(struct phonethdr)))
386 goto out;
387
388
389 ph = pn_hdr(skb);
390 len = get_unaligned_be16(&ph->pn_length);
391 if (len < 2)
392 goto out;
393 len -= 2;
394 if ((len > skb->len) || pskb_trim(skb, len))
395 goto out;
396 skb_reset_transport_header(skb);
397
398 pn_skb_get_dst_sockaddr(skb, &sa);
399
400
401 if (pn_sockaddr_get_addr(&sa) == PNADDR_BROADCAST) {
402 pn_deliver_sock_broadcast(net, skb);
403 goto out;
404 }
405
406
407 if (pn_sockaddr_get_object(&sa) == 0) {
408 struct sock *sk = pn_find_sock_by_res(net, sa.spn_resource);
409 if (sk)
410 return sk_receive_skb(sk, skb, 0);
411 }
412
413
414 if (phonet_address_lookup(net, pn_sockaddr_get_addr(&sa)) == 0) {
415
416 struct sock *sk = pn_find_sock_by_sa(net, &sa);
417
418 if (sk)
419 return sk_receive_skb(sk, skb, 0);
420
421 if (can_respond(skb)) {
422 send_obj_unreachable(skb);
423 send_reset_indications(skb);
424 }
425 } else if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
426 goto out;
427 else {
428
429 struct net_device *out_dev;
430
431 out_dev = phonet_route_output(net, pn_sockaddr_get_addr(&sa));
432 if (!out_dev) {
433 net_dbg_ratelimited("No Phonet route to %02X\n",
434 pn_sockaddr_get_addr(&sa));
435 goto out;
436 }
437
438 __skb_push(skb, sizeof(struct phonethdr));
439 skb->dev = out_dev;
440 if (out_dev == dev) {
441 net_dbg_ratelimited("Phonet loop to %02X on %s\n",
442 pn_sockaddr_get_addr(&sa),
443 dev->name);
444 goto out_dev;
445 }
446
447 if (skb_cow_head(skb, out_dev->hard_header_len))
448 goto out_dev;
449
450 if (dev_hard_header(skb, out_dev, ETH_P_PHONET, NULL, NULL,
451 skb->len) < 0)
452 goto out_dev;
453 dev_queue_xmit(skb);
454 dev_put(out_dev);
455 return NET_RX_SUCCESS;
456out_dev:
457 dev_put(out_dev);
458 }
459
460out:
461 kfree_skb(skb);
462 return NET_RX_DROP;
463}
464
465static struct packet_type phonet_packet_type __read_mostly = {
466 .type = cpu_to_be16(ETH_P_PHONET),
467 .func = phonet_rcv,
468};
469
470static DEFINE_MUTEX(proto_tab_lock);
471
472int __init_or_module phonet_proto_register(unsigned int protocol,
473 const struct phonet_protocol *pp)
474{
475 int err = 0;
476
477 if (protocol >= PHONET_NPROTO)
478 return -EINVAL;
479
480 err = proto_register(pp->prot, 1);
481 if (err)
482 return err;
483
484 mutex_lock(&proto_tab_lock);
485 if (proto_tab[protocol])
486 err = -EBUSY;
487 else
488 rcu_assign_pointer(proto_tab[protocol], pp);
489 mutex_unlock(&proto_tab_lock);
490
491 return err;
492}
493EXPORT_SYMBOL(phonet_proto_register);
494
495void phonet_proto_unregister(unsigned int protocol,
496 const struct phonet_protocol *pp)
497{
498 mutex_lock(&proto_tab_lock);
499 BUG_ON(proto_tab[protocol] != pp);
500 RCU_INIT_POINTER(proto_tab[protocol], NULL);
501 mutex_unlock(&proto_tab_lock);
502 synchronize_rcu();
503 proto_unregister(pp->prot);
504}
505EXPORT_SYMBOL(phonet_proto_unregister);
506
507
508static int __init phonet_init(void)
509{
510 int err;
511
512 err = phonet_device_init();
513 if (err)
514 return err;
515
516 pn_sock_init();
517 err = sock_register(&phonet_proto_family);
518 if (err) {
519 printk(KERN_ALERT
520 "phonet protocol family initialization failed\n");
521 goto err_sock;
522 }
523
524 dev_add_pack(&phonet_packet_type);
525 phonet_sysctl_init();
526
527 err = isi_register();
528 if (err)
529 goto err;
530 return 0;
531
532err:
533 phonet_sysctl_exit();
534 sock_unregister(PF_PHONET);
535 dev_remove_pack(&phonet_packet_type);
536err_sock:
537 phonet_device_exit();
538 return err;
539}
540
541static void __exit phonet_exit(void)
542{
543 isi_unregister();
544 phonet_sysctl_exit();
545 sock_unregister(PF_PHONET);
546 dev_remove_pack(&phonet_packet_type);
547 phonet_device_exit();
548}
549
550module_init(phonet_init);
551module_exit(phonet_exit);
552MODULE_DESCRIPTION("Phonet protocol stack for Linux");
553MODULE_LICENSE("GPL");
554MODULE_ALIAS_NETPROTO(PF_PHONET);
555
