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