Merge tag 'rproc-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/remoteproc...
[linux.git] / net / phonet / pep.c
blob53a858478e22f0fd12bdf29ffaa9266cd7dec666
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * File: pep.c
5 * Phonet pipe protocol end point socket
7 * Copyright (C) 2008 Nokia Corporation.
9 * Author: RĂ©mi Denis-Courmont
12 #include <linux/kernel.h>
13 #include <linux/sched/signal.h>
14 #include <linux/slab.h>
15 #include <linux/socket.h>
16 #include <net/sock.h>
17 #include <net/tcp_states.h>
18 #include <asm/ioctls.h>
20 #include <linux/phonet.h>
21 #include <linux/module.h>
22 #include <net/phonet/phonet.h>
23 #include <net/phonet/pep.h>
24 #include <net/phonet/gprs.h>
26 /* sk_state values:
27 * TCP_CLOSE sock not in use yet
28 * TCP_CLOSE_WAIT disconnected pipe
29 * TCP_LISTEN listening pipe endpoint
30 * TCP_SYN_RECV connected pipe in disabled state
31 * TCP_ESTABLISHED connected pipe in enabled state
33 * pep_sock locking:
34 * - sk_state, hlist: sock lock needed
35 * - listener: read only
36 * - pipe_handle: read only
39 #define CREDITS_MAX 10
40 #define CREDITS_THR 7
42 #define pep_sb_size(s) (((s) + 5) & ~3) /* 2-bytes head, 32-bits aligned */
44 /* Get the next TLV sub-block. */
45 static unsigned char *pep_get_sb(struct sk_buff *skb, u8 *ptype, u8 *plen,
46 void *buf)
48 void *data = NULL;
49 struct {
50 u8 sb_type;
51 u8 sb_len;
52 } *ph, h;
53 int buflen = *plen;
55 ph = skb_header_pointer(skb, 0, 2, &h);
56 if (ph == NULL || ph->sb_len < 2 || !pskb_may_pull(skb, ph->sb_len))
57 return NULL;
58 ph->sb_len -= 2;
59 *ptype = ph->sb_type;
60 *plen = ph->sb_len;
62 if (buflen > ph->sb_len)
63 buflen = ph->sb_len;
64 data = skb_header_pointer(skb, 2, buflen, buf);
65 __skb_pull(skb, 2 + ph->sb_len);
66 return data;
69 static struct sk_buff *pep_alloc_skb(struct sock *sk, const void *payload,
70 int len, gfp_t priority)
72 struct sk_buff *skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority);
73 if (!skb)
74 return NULL;
75 skb_set_owner_w(skb, sk);
77 skb_reserve(skb, MAX_PNPIPE_HEADER);
78 __skb_put(skb, len);
79 skb_copy_to_linear_data(skb, payload, len);
80 __skb_push(skb, sizeof(struct pnpipehdr));
81 skb_reset_transport_header(skb);
82 return skb;
85 static int pep_reply(struct sock *sk, struct sk_buff *oskb, u8 code,
86 const void *data, int len, gfp_t priority)
88 const struct pnpipehdr *oph = pnp_hdr(oskb);
89 struct pnpipehdr *ph;
90 struct sk_buff *skb;
91 struct sockaddr_pn peer;
93 skb = pep_alloc_skb(sk, data, len, priority);
94 if (!skb)
95 return -ENOMEM;
97 ph = pnp_hdr(skb);
98 ph->utid = oph->utid;
99 ph->message_id = oph->message_id + 1; /* REQ -> RESP */
100 ph->pipe_handle = oph->pipe_handle;
101 ph->error_code = code;
103 pn_skb_get_src_sockaddr(oskb, &peer);
104 return pn_skb_send(sk, skb, &peer);
107 static int pep_indicate(struct sock *sk, u8 id, u8 code,
108 const void *data, int len, gfp_t priority)
110 struct pep_sock *pn = pep_sk(sk);
111 struct pnpipehdr *ph;
112 struct sk_buff *skb;
114 skb = pep_alloc_skb(sk, data, len, priority);
115 if (!skb)
116 return -ENOMEM;
118 ph = pnp_hdr(skb);
119 ph->utid = 0;
120 ph->message_id = id;
121 ph->pipe_handle = pn->pipe_handle;
122 ph->error_code = code;
123 return pn_skb_send(sk, skb, NULL);
126 #define PAD 0x00
128 static int pipe_handler_request(struct sock *sk, u8 id, u8 code,
129 const void *data, int len)
131 struct pep_sock *pn = pep_sk(sk);
132 struct pnpipehdr *ph;
133 struct sk_buff *skb;
135 skb = pep_alloc_skb(sk, data, len, GFP_KERNEL);
136 if (!skb)
137 return -ENOMEM;
139 ph = pnp_hdr(skb);
140 ph->utid = id; /* whatever */
141 ph->message_id = id;
142 ph->pipe_handle = pn->pipe_handle;
143 ph->error_code = code;
144 return pn_skb_send(sk, skb, NULL);
147 static int pipe_handler_send_created_ind(struct sock *sk)
149 struct pep_sock *pn = pep_sk(sk);
150 u8 data[4] = {
151 PN_PIPE_SB_NEGOTIATED_FC, pep_sb_size(2),
152 pn->tx_fc, pn->rx_fc,
155 return pep_indicate(sk, PNS_PIPE_CREATED_IND, 1 /* sub-blocks */,
156 data, 4, GFP_ATOMIC);
159 static int pep_accept_conn(struct sock *sk, struct sk_buff *skb)
161 static const u8 data[20] = {
162 PAD, PAD, PAD, 2 /* sub-blocks */,
163 PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD,
164 PN_MULTI_CREDIT_FLOW_CONTROL,
165 PN_ONE_CREDIT_FLOW_CONTROL,
166 PN_LEGACY_FLOW_CONTROL,
167 PAD,
168 PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD,
169 PN_MULTI_CREDIT_FLOW_CONTROL,
170 PN_ONE_CREDIT_FLOW_CONTROL,
171 PN_LEGACY_FLOW_CONTROL,
172 PAD,
175 might_sleep();
176 return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data),
177 GFP_KERNEL);
180 static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code,
181 gfp_t priority)
183 static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ };
184 WARN_ON(code == PN_PIPE_NO_ERROR);
185 return pep_reply(sk, skb, code, data, sizeof(data), priority);
188 /* Control requests are not sent by the pipe service and have a specific
189 * message format. */
190 static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code,
191 gfp_t priority)
193 const struct pnpipehdr *oph = pnp_hdr(oskb);
194 struct sk_buff *skb;
195 struct pnpipehdr *ph;
196 struct sockaddr_pn dst;
197 u8 data[4] = {
198 oph->pep_type, /* PEP type */
199 code, /* error code, at an unusual offset */
200 PAD, PAD,
203 skb = pep_alloc_skb(sk, data, 4, priority);
204 if (!skb)
205 return -ENOMEM;
207 ph = pnp_hdr(skb);
208 ph->utid = oph->utid;
209 ph->message_id = PNS_PEP_CTRL_RESP;
210 ph->pipe_handle = oph->pipe_handle;
211 ph->data0 = oph->data[0]; /* CTRL id */
213 pn_skb_get_src_sockaddr(oskb, &dst);
214 return pn_skb_send(sk, skb, &dst);
217 static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority)
219 u8 data[4] = { type, PAD, PAD, status };
221 return pep_indicate(sk, PNS_PEP_STATUS_IND, PN_PEP_TYPE_COMMON,
222 data, 4, priority);
225 /* Send our RX flow control information to the sender.
226 * Socket must be locked. */
227 static void pipe_grant_credits(struct sock *sk, gfp_t priority)
229 struct pep_sock *pn = pep_sk(sk);
231 BUG_ON(sk->sk_state != TCP_ESTABLISHED);
233 switch (pn->rx_fc) {
234 case PN_LEGACY_FLOW_CONTROL: /* TODO */
235 break;
236 case PN_ONE_CREDIT_FLOW_CONTROL:
237 if (pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL,
238 PEP_IND_READY, priority) == 0)
239 pn->rx_credits = 1;
240 break;
241 case PN_MULTI_CREDIT_FLOW_CONTROL:
242 if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX)
243 break;
244 if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS,
245 CREDITS_MAX - pn->rx_credits,
246 priority) == 0)
247 pn->rx_credits = CREDITS_MAX;
248 break;
252 static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb)
254 struct pep_sock *pn = pep_sk(sk);
255 struct pnpipehdr *hdr;
256 int wake = 0;
258 if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
259 return -EINVAL;
261 hdr = pnp_hdr(skb);
262 if (hdr->pep_type != PN_PEP_TYPE_COMMON) {
263 net_dbg_ratelimited("Phonet unknown PEP type: %u\n",
264 (unsigned int)hdr->pep_type);
265 return -EOPNOTSUPP;
268 switch (hdr->data[0]) {
269 case PN_PEP_IND_FLOW_CONTROL:
270 switch (pn->tx_fc) {
271 case PN_LEGACY_FLOW_CONTROL:
272 switch (hdr->data[3]) {
273 case PEP_IND_BUSY:
274 atomic_set(&pn->tx_credits, 0);
275 break;
276 case PEP_IND_READY:
277 atomic_set(&pn->tx_credits, wake = 1);
278 break;
280 break;
281 case PN_ONE_CREDIT_FLOW_CONTROL:
282 if (hdr->data[3] == PEP_IND_READY)
283 atomic_set(&pn->tx_credits, wake = 1);
284 break;
286 break;
288 case PN_PEP_IND_ID_MCFC_GRANT_CREDITS:
289 if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL)
290 break;
291 atomic_add(wake = hdr->data[3], &pn->tx_credits);
292 break;
294 default:
295 net_dbg_ratelimited("Phonet unknown PEP indication: %u\n",
296 (unsigned int)hdr->data[0]);
297 return -EOPNOTSUPP;
299 if (wake)
300 sk->sk_write_space(sk);
301 return 0;
304 static int pipe_rcv_created(struct sock *sk, struct sk_buff *skb)
306 struct pep_sock *pn = pep_sk(sk);
307 struct pnpipehdr *hdr = pnp_hdr(skb);
308 u8 n_sb = hdr->data0;
310 pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
311 __skb_pull(skb, sizeof(*hdr));
312 while (n_sb > 0) {
313 u8 type, buf[2], len = sizeof(buf);
314 u8 *data = pep_get_sb(skb, &type, &len, buf);
316 if (data == NULL)
317 return -EINVAL;
318 switch (type) {
319 case PN_PIPE_SB_NEGOTIATED_FC:
320 if (len < 2 || (data[0] | data[1]) > 3)
321 break;
322 pn->tx_fc = data[0] & 3;
323 pn->rx_fc = data[1] & 3;
324 break;
326 n_sb--;
328 return 0;
331 /* Queue an skb to a connected sock.
332 * Socket lock must be held. */
333 static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
335 struct pep_sock *pn = pep_sk(sk);
336 struct pnpipehdr *hdr = pnp_hdr(skb);
337 struct sk_buff_head *queue;
338 int err = 0;
340 BUG_ON(sk->sk_state == TCP_CLOSE_WAIT);
342 switch (hdr->message_id) {
343 case PNS_PEP_CONNECT_REQ:
344 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_ATOMIC);
345 break;
347 case PNS_PEP_DISCONNECT_REQ:
348 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
349 sk->sk_state = TCP_CLOSE_WAIT;
350 if (!sock_flag(sk, SOCK_DEAD))
351 sk->sk_state_change(sk);
352 break;
354 case PNS_PEP_ENABLE_REQ:
355 /* Wait for PNS_PIPE_(ENABLED|REDIRECTED)_IND */
356 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
357 break;
359 case PNS_PEP_RESET_REQ:
360 switch (hdr->state_after_reset) {
361 case PN_PIPE_DISABLE:
362 pn->init_enable = 0;
363 break;
364 case PN_PIPE_ENABLE:
365 pn->init_enable = 1;
366 break;
367 default: /* not allowed to send an error here!? */
368 err = -EINVAL;
369 goto out;
371 fallthrough;
372 case PNS_PEP_DISABLE_REQ:
373 atomic_set(&pn->tx_credits, 0);
374 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
375 break;
377 case PNS_PEP_CTRL_REQ:
378 if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) {
379 atomic_inc(&sk->sk_drops);
380 break;
382 __skb_pull(skb, 4);
383 queue = &pn->ctrlreq_queue;
384 goto queue;
386 case PNS_PIPE_ALIGNED_DATA:
387 __skb_pull(skb, 1);
388 fallthrough;
389 case PNS_PIPE_DATA:
390 __skb_pull(skb, 3); /* Pipe data header */
391 if (!pn_flow_safe(pn->rx_fc)) {
392 err = sock_queue_rcv_skb(sk, skb);
393 if (!err)
394 return NET_RX_SUCCESS;
395 err = -ENOBUFS;
396 break;
399 if (pn->rx_credits == 0) {
400 atomic_inc(&sk->sk_drops);
401 err = -ENOBUFS;
402 break;
404 pn->rx_credits--;
405 queue = &sk->sk_receive_queue;
406 goto queue;
408 case PNS_PEP_STATUS_IND:
409 pipe_rcv_status(sk, skb);
410 break;
412 case PNS_PIPE_REDIRECTED_IND:
413 err = pipe_rcv_created(sk, skb);
414 break;
416 case PNS_PIPE_CREATED_IND:
417 err = pipe_rcv_created(sk, skb);
418 if (err)
419 break;
420 fallthrough;
421 case PNS_PIPE_RESET_IND:
422 if (!pn->init_enable)
423 break;
424 fallthrough;
425 case PNS_PIPE_ENABLED_IND:
426 if (!pn_flow_safe(pn->tx_fc)) {
427 atomic_set(&pn->tx_credits, 1);
428 sk->sk_write_space(sk);
430 if (sk->sk_state == TCP_ESTABLISHED)
431 break; /* Nothing to do */
432 sk->sk_state = TCP_ESTABLISHED;
433 pipe_grant_credits(sk, GFP_ATOMIC);
434 break;
436 case PNS_PIPE_DISABLED_IND:
437 sk->sk_state = TCP_SYN_RECV;
438 pn->rx_credits = 0;
439 break;
441 default:
442 net_dbg_ratelimited("Phonet unknown PEP message: %u\n",
443 hdr->message_id);
444 err = -EINVAL;
446 out:
447 kfree_skb(skb);
448 return (err == -ENOBUFS) ? NET_RX_DROP : NET_RX_SUCCESS;
450 queue:
451 skb->dev = NULL;
452 skb_set_owner_r(skb, sk);
453 skb_queue_tail(queue, skb);
454 if (!sock_flag(sk, SOCK_DEAD))
455 sk->sk_data_ready(sk);
456 return NET_RX_SUCCESS;
459 /* Destroy connected sock. */
460 static void pipe_destruct(struct sock *sk)
462 struct pep_sock *pn = pep_sk(sk);
464 skb_queue_purge(&sk->sk_receive_queue);
465 skb_queue_purge(&pn->ctrlreq_queue);
468 static u8 pipe_negotiate_fc(const u8 *fcs, unsigned int n)
470 unsigned int i;
471 u8 final_fc = PN_NO_FLOW_CONTROL;
473 for (i = 0; i < n; i++) {
474 u8 fc = fcs[i];
476 if (fc > final_fc && fc < PN_MAX_FLOW_CONTROL)
477 final_fc = fc;
479 return final_fc;
482 static int pep_connresp_rcv(struct sock *sk, struct sk_buff *skb)
484 struct pep_sock *pn = pep_sk(sk);
485 struct pnpipehdr *hdr;
486 u8 n_sb;
488 if (!pskb_pull(skb, sizeof(*hdr) + 4))
489 return -EINVAL;
491 hdr = pnp_hdr(skb);
492 if (hdr->error_code != PN_PIPE_NO_ERROR)
493 return -ECONNREFUSED;
495 /* Parse sub-blocks */
496 n_sb = hdr->data[3];
497 while (n_sb > 0) {
498 u8 type, buf[6], len = sizeof(buf);
499 const u8 *data = pep_get_sb(skb, &type, &len, buf);
501 if (data == NULL)
502 return -EINVAL;
504 switch (type) {
505 case PN_PIPE_SB_REQUIRED_FC_TX:
506 if (len < 2 || len < data[0])
507 break;
508 pn->tx_fc = pipe_negotiate_fc(data + 2, len - 2);
509 break;
511 case PN_PIPE_SB_PREFERRED_FC_RX:
512 if (len < 2 || len < data[0])
513 break;
514 pn->rx_fc = pipe_negotiate_fc(data + 2, len - 2);
515 break;
518 n_sb--;
521 return pipe_handler_send_created_ind(sk);
524 static int pep_enableresp_rcv(struct sock *sk, struct sk_buff *skb)
526 struct pnpipehdr *hdr = pnp_hdr(skb);
528 if (hdr->error_code != PN_PIPE_NO_ERROR)
529 return -ECONNREFUSED;
531 return pep_indicate(sk, PNS_PIPE_ENABLED_IND, 0 /* sub-blocks */,
532 NULL, 0, GFP_ATOMIC);
536 static void pipe_start_flow_control(struct sock *sk)
538 struct pep_sock *pn = pep_sk(sk);
540 if (!pn_flow_safe(pn->tx_fc)) {
541 atomic_set(&pn->tx_credits, 1);
542 sk->sk_write_space(sk);
544 pipe_grant_credits(sk, GFP_ATOMIC);
547 /* Queue an skb to an actively connected sock.
548 * Socket lock must be held. */
549 static int pipe_handler_do_rcv(struct sock *sk, struct sk_buff *skb)
551 struct pep_sock *pn = pep_sk(sk);
552 struct pnpipehdr *hdr = pnp_hdr(skb);
553 int err = NET_RX_SUCCESS;
555 switch (hdr->message_id) {
556 case PNS_PIPE_ALIGNED_DATA:
557 __skb_pull(skb, 1);
558 fallthrough;
559 case PNS_PIPE_DATA:
560 __skb_pull(skb, 3); /* Pipe data header */
561 if (!pn_flow_safe(pn->rx_fc)) {
562 err = sock_queue_rcv_skb(sk, skb);
563 if (!err)
564 return NET_RX_SUCCESS;
565 err = NET_RX_DROP;
566 break;
569 if (pn->rx_credits == 0) {
570 atomic_inc(&sk->sk_drops);
571 err = NET_RX_DROP;
572 break;
574 pn->rx_credits--;
575 skb->dev = NULL;
576 skb_set_owner_r(skb, sk);
577 skb_queue_tail(&sk->sk_receive_queue, skb);
578 if (!sock_flag(sk, SOCK_DEAD))
579 sk->sk_data_ready(sk);
580 return NET_RX_SUCCESS;
582 case PNS_PEP_CONNECT_RESP:
583 if (sk->sk_state != TCP_SYN_SENT)
584 break;
585 if (!sock_flag(sk, SOCK_DEAD))
586 sk->sk_state_change(sk);
587 if (pep_connresp_rcv(sk, skb)) {
588 sk->sk_state = TCP_CLOSE_WAIT;
589 break;
591 if (pn->init_enable == PN_PIPE_DISABLE)
592 sk->sk_state = TCP_SYN_RECV;
593 else {
594 sk->sk_state = TCP_ESTABLISHED;
595 pipe_start_flow_control(sk);
597 break;
599 case PNS_PEP_ENABLE_RESP:
600 if (sk->sk_state != TCP_SYN_SENT)
601 break;
603 if (pep_enableresp_rcv(sk, skb)) {
604 sk->sk_state = TCP_CLOSE_WAIT;
605 break;
608 sk->sk_state = TCP_ESTABLISHED;
609 pipe_start_flow_control(sk);
610 break;
612 case PNS_PEP_DISCONNECT_RESP:
613 /* sock should already be dead, nothing to do */
614 break;
616 case PNS_PEP_STATUS_IND:
617 pipe_rcv_status(sk, skb);
618 break;
620 kfree_skb(skb);
621 return err;
624 /* Listening sock must be locked */
625 static struct sock *pep_find_pipe(const struct hlist_head *hlist,
626 const struct sockaddr_pn *dst,
627 u8 pipe_handle)
629 struct sock *sknode;
630 u16 dobj = pn_sockaddr_get_object(dst);
632 sk_for_each(sknode, hlist) {
633 struct pep_sock *pnnode = pep_sk(sknode);
635 /* Ports match, but addresses might not: */
636 if (pnnode->pn_sk.sobject != dobj)
637 continue;
638 if (pnnode->pipe_handle != pipe_handle)
639 continue;
640 if (sknode->sk_state == TCP_CLOSE_WAIT)
641 continue;
643 sock_hold(sknode);
644 return sknode;
646 return NULL;
650 * Deliver an skb to a listening sock.
651 * Socket lock must be held.
652 * We then queue the skb to the right connected sock (if any).
654 static int pep_do_rcv(struct sock *sk, struct sk_buff *skb)
656 struct pep_sock *pn = pep_sk(sk);
657 struct sock *sknode;
658 struct pnpipehdr *hdr;
659 struct sockaddr_pn dst;
660 u8 pipe_handle;
662 if (!pskb_may_pull(skb, sizeof(*hdr)))
663 goto drop;
665 hdr = pnp_hdr(skb);
666 pipe_handle = hdr->pipe_handle;
667 if (pipe_handle == PN_PIPE_INVALID_HANDLE)
668 goto drop;
670 pn_skb_get_dst_sockaddr(skb, &dst);
672 /* Look for an existing pipe handle */
673 sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
674 if (sknode)
675 return sk_receive_skb(sknode, skb, 1);
677 switch (hdr->message_id) {
678 case PNS_PEP_CONNECT_REQ:
679 if (sk->sk_state != TCP_LISTEN || sk_acceptq_is_full(sk)) {
680 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE,
681 GFP_ATOMIC);
682 break;
684 skb_queue_head(&sk->sk_receive_queue, skb);
685 sk_acceptq_added(sk);
686 if (!sock_flag(sk, SOCK_DEAD))
687 sk->sk_data_ready(sk);
688 return NET_RX_SUCCESS;
690 case PNS_PEP_DISCONNECT_REQ:
691 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
692 break;
694 case PNS_PEP_CTRL_REQ:
695 pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC);
696 break;
698 case PNS_PEP_RESET_REQ:
699 case PNS_PEP_ENABLE_REQ:
700 case PNS_PEP_DISABLE_REQ:
701 /* invalid handle is not even allowed here! */
702 break;
704 default:
705 if ((1 << sk->sk_state)
706 & ~(TCPF_CLOSE|TCPF_LISTEN|TCPF_CLOSE_WAIT))
707 /* actively connected socket */
708 return pipe_handler_do_rcv(sk, skb);
710 drop:
711 kfree_skb(skb);
712 return NET_RX_SUCCESS;
715 static int pipe_do_remove(struct sock *sk)
717 struct pep_sock *pn = pep_sk(sk);
718 struct pnpipehdr *ph;
719 struct sk_buff *skb;
721 skb = pep_alloc_skb(sk, NULL, 0, GFP_KERNEL);
722 if (!skb)
723 return -ENOMEM;
725 ph = pnp_hdr(skb);
726 ph->utid = 0;
727 ph->message_id = PNS_PIPE_REMOVE_REQ;
728 ph->pipe_handle = pn->pipe_handle;
729 ph->data0 = PAD;
730 return pn_skb_send(sk, skb, NULL);
733 /* associated socket ceases to exist */
734 static void pep_sock_close(struct sock *sk, long timeout)
736 struct pep_sock *pn = pep_sk(sk);
737 int ifindex = 0;
739 sock_hold(sk); /* keep a reference after sk_common_release() */
740 sk_common_release(sk);
742 lock_sock(sk);
743 if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED)) {
744 if (sk->sk_backlog_rcv == pipe_do_rcv)
745 /* Forcefully remove dangling Phonet pipe */
746 pipe_do_remove(sk);
747 else
748 pipe_handler_request(sk, PNS_PEP_DISCONNECT_REQ, PAD,
749 NULL, 0);
751 sk->sk_state = TCP_CLOSE;
753 ifindex = pn->ifindex;
754 pn->ifindex = 0;
755 release_sock(sk);
757 if (ifindex)
758 gprs_detach(sk);
759 sock_put(sk);
762 static struct sock *pep_sock_accept(struct sock *sk,
763 struct proto_accept_arg *arg)
765 struct pep_sock *pn = pep_sk(sk), *newpn;
766 struct sock *newsk = NULL;
767 struct sk_buff *skb;
768 struct pnpipehdr *hdr;
769 struct sockaddr_pn dst, src;
770 int err;
771 u16 peer_type;
772 u8 pipe_handle, enabled, n_sb;
773 u8 aligned = 0;
775 skb = skb_recv_datagram(sk, (arg->flags & O_NONBLOCK) ? MSG_DONTWAIT : 0,
776 &arg->err);
777 if (!skb)
778 return NULL;
780 lock_sock(sk);
781 if (sk->sk_state != TCP_LISTEN) {
782 err = -EINVAL;
783 goto drop;
785 sk_acceptq_removed(sk);
787 err = -EPROTO;
788 if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
789 goto drop;
791 hdr = pnp_hdr(skb);
792 pipe_handle = hdr->pipe_handle;
793 switch (hdr->state_after_connect) {
794 case PN_PIPE_DISABLE:
795 enabled = 0;
796 break;
797 case PN_PIPE_ENABLE:
798 enabled = 1;
799 break;
800 default:
801 pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM,
802 GFP_KERNEL);
803 goto drop;
805 peer_type = hdr->other_pep_type << 8;
807 /* Parse sub-blocks (options) */
808 n_sb = hdr->data[3];
809 while (n_sb > 0) {
810 u8 type, buf[1], len = sizeof(buf);
811 const u8 *data = pep_get_sb(skb, &type, &len, buf);
813 if (data == NULL)
814 goto drop;
815 switch (type) {
816 case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE:
817 if (len < 1)
818 goto drop;
819 peer_type = (peer_type & 0xff00) | data[0];
820 break;
821 case PN_PIPE_SB_ALIGNED_DATA:
822 aligned = data[0] != 0;
823 break;
825 n_sb--;
828 /* Check for duplicate pipe handle */
829 newsk = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
830 if (unlikely(newsk)) {
831 __sock_put(newsk);
832 newsk = NULL;
833 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_KERNEL);
834 goto drop;
837 /* Create a new to-be-accepted sock */
838 newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_KERNEL, sk->sk_prot,
839 arg->kern);
840 if (!newsk) {
841 pep_reject_conn(sk, skb, PN_PIPE_ERR_OVERLOAD, GFP_KERNEL);
842 err = -ENOBUFS;
843 goto drop;
846 sock_init_data(NULL, newsk);
847 newsk->sk_state = TCP_SYN_RECV;
848 newsk->sk_backlog_rcv = pipe_do_rcv;
849 newsk->sk_protocol = sk->sk_protocol;
850 newsk->sk_destruct = pipe_destruct;
852 newpn = pep_sk(newsk);
853 pn_skb_get_dst_sockaddr(skb, &dst);
854 pn_skb_get_src_sockaddr(skb, &src);
855 newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst);
856 newpn->pn_sk.dobject = pn_sockaddr_get_object(&src);
857 newpn->pn_sk.resource = pn_sockaddr_get_resource(&dst);
858 sock_hold(sk);
859 newpn->listener = sk;
860 skb_queue_head_init(&newpn->ctrlreq_queue);
861 newpn->pipe_handle = pipe_handle;
862 atomic_set(&newpn->tx_credits, 0);
863 newpn->ifindex = 0;
864 newpn->peer_type = peer_type;
865 newpn->rx_credits = 0;
866 newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL;
867 newpn->init_enable = enabled;
868 newpn->aligned = aligned;
870 err = pep_accept_conn(newsk, skb);
871 if (err) {
872 __sock_put(sk);
873 sock_put(newsk);
874 newsk = NULL;
875 goto drop;
877 sk_add_node(newsk, &pn->hlist);
878 drop:
879 release_sock(sk);
880 kfree_skb(skb);
881 arg->err = err;
882 return newsk;
885 static int pep_sock_connect(struct sock *sk, struct sockaddr *addr, int len)
887 struct pep_sock *pn = pep_sk(sk);
888 int err;
889 u8 data[4] = { 0 /* sub-blocks */, PAD, PAD, PAD };
891 if (pn->pipe_handle == PN_PIPE_INVALID_HANDLE)
892 pn->pipe_handle = 1; /* anything but INVALID_HANDLE */
894 err = pipe_handler_request(sk, PNS_PEP_CONNECT_REQ,
895 pn->init_enable, data, 4);
896 if (err) {
897 pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
898 return err;
901 sk->sk_state = TCP_SYN_SENT;
903 return 0;
906 static int pep_sock_enable(struct sock *sk, struct sockaddr *addr, int len)
908 int err;
910 err = pipe_handler_request(sk, PNS_PEP_ENABLE_REQ, PAD,
911 NULL, 0);
912 if (err)
913 return err;
915 sk->sk_state = TCP_SYN_SENT;
917 return 0;
920 static unsigned int pep_first_packet_length(struct sock *sk)
922 struct pep_sock *pn = pep_sk(sk);
923 struct sk_buff_head *q;
924 struct sk_buff *skb;
925 unsigned int len = 0;
926 bool found = false;
928 if (sock_flag(sk, SOCK_URGINLINE)) {
929 q = &pn->ctrlreq_queue;
930 spin_lock_bh(&q->lock);
931 skb = skb_peek(q);
932 if (skb) {
933 len = skb->len;
934 found = true;
936 spin_unlock_bh(&q->lock);
939 if (likely(!found)) {
940 q = &sk->sk_receive_queue;
941 spin_lock_bh(&q->lock);
942 skb = skb_peek(q);
943 if (skb)
944 len = skb->len;
945 spin_unlock_bh(&q->lock);
948 return len;
951 static int pep_ioctl(struct sock *sk, int cmd, int *karg)
953 struct pep_sock *pn = pep_sk(sk);
954 int ret = -ENOIOCTLCMD;
956 switch (cmd) {
957 case SIOCINQ:
958 if (sk->sk_state == TCP_LISTEN) {
959 ret = -EINVAL;
960 break;
963 *karg = pep_first_packet_length(sk);
964 ret = 0;
965 break;
967 case SIOCPNENABLEPIPE:
968 lock_sock(sk);
969 if (sk->sk_state == TCP_SYN_SENT)
970 ret = -EBUSY;
971 else if (sk->sk_state == TCP_ESTABLISHED)
972 ret = -EISCONN;
973 else if (!pn->pn_sk.sobject)
974 ret = -EADDRNOTAVAIL;
975 else
976 ret = pep_sock_enable(sk, NULL, 0);
977 release_sock(sk);
978 break;
981 return ret;
984 static int pep_init(struct sock *sk)
986 struct pep_sock *pn = pep_sk(sk);
988 sk->sk_destruct = pipe_destruct;
989 INIT_HLIST_HEAD(&pn->hlist);
990 pn->listener = NULL;
991 skb_queue_head_init(&pn->ctrlreq_queue);
992 atomic_set(&pn->tx_credits, 0);
993 pn->ifindex = 0;
994 pn->peer_type = 0;
995 pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
996 pn->rx_credits = 0;
997 pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
998 pn->init_enable = 1;
999 pn->aligned = 0;
1000 return 0;
1003 static int pep_setsockopt(struct sock *sk, int level, int optname,
1004 sockptr_t optval, unsigned int optlen)
1006 struct pep_sock *pn = pep_sk(sk);
1007 int val = 0, err = 0;
1009 if (level != SOL_PNPIPE)
1010 return -ENOPROTOOPT;
1011 if (optlen >= sizeof(int)) {
1012 if (copy_from_sockptr(&val, optval, sizeof(int)))
1013 return -EFAULT;
1016 lock_sock(sk);
1017 switch (optname) {
1018 case PNPIPE_ENCAP:
1019 if (val && val != PNPIPE_ENCAP_IP) {
1020 err = -EINVAL;
1021 break;
1023 if (!pn->ifindex == !val)
1024 break; /* Nothing to do! */
1025 if (!capable(CAP_NET_ADMIN)) {
1026 err = -EPERM;
1027 break;
1029 if (val) {
1030 release_sock(sk);
1031 err = gprs_attach(sk);
1032 if (err > 0) {
1033 pn->ifindex = err;
1034 err = 0;
1036 } else {
1037 pn->ifindex = 0;
1038 release_sock(sk);
1039 gprs_detach(sk);
1040 err = 0;
1042 goto out_norel;
1044 case PNPIPE_HANDLE:
1045 if ((sk->sk_state == TCP_CLOSE) &&
1046 (val >= 0) && (val < PN_PIPE_INVALID_HANDLE))
1047 pn->pipe_handle = val;
1048 else
1049 err = -EINVAL;
1050 break;
1052 case PNPIPE_INITSTATE:
1053 pn->init_enable = !!val;
1054 break;
1056 default:
1057 err = -ENOPROTOOPT;
1059 release_sock(sk);
1061 out_norel:
1062 return err;
1065 static int pep_getsockopt(struct sock *sk, int level, int optname,
1066 char __user *optval, int __user *optlen)
1068 struct pep_sock *pn = pep_sk(sk);
1069 int len, val;
1071 if (level != SOL_PNPIPE)
1072 return -ENOPROTOOPT;
1073 if (get_user(len, optlen))
1074 return -EFAULT;
1076 switch (optname) {
1077 case PNPIPE_ENCAP:
1078 val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE;
1079 break;
1081 case PNPIPE_IFINDEX:
1082 val = pn->ifindex;
1083 break;
1085 case PNPIPE_HANDLE:
1086 val = pn->pipe_handle;
1087 if (val == PN_PIPE_INVALID_HANDLE)
1088 return -EINVAL;
1089 break;
1091 case PNPIPE_INITSTATE:
1092 val = pn->init_enable;
1093 break;
1095 default:
1096 return -ENOPROTOOPT;
1099 len = min_t(unsigned int, sizeof(int), len);
1100 if (put_user(len, optlen))
1101 return -EFAULT;
1102 if (put_user(val, (int __user *) optval))
1103 return -EFAULT;
1104 return 0;
1107 static int pipe_skb_send(struct sock *sk, struct sk_buff *skb)
1109 struct pep_sock *pn = pep_sk(sk);
1110 struct pnpipehdr *ph;
1111 int err;
1113 if (pn_flow_safe(pn->tx_fc) &&
1114 !atomic_add_unless(&pn->tx_credits, -1, 0)) {
1115 kfree_skb(skb);
1116 return -ENOBUFS;
1119 skb_push(skb, 3 + pn->aligned);
1120 skb_reset_transport_header(skb);
1121 ph = pnp_hdr(skb);
1122 ph->utid = 0;
1123 if (pn->aligned) {
1124 ph->message_id = PNS_PIPE_ALIGNED_DATA;
1125 ph->data0 = 0; /* padding */
1126 } else
1127 ph->message_id = PNS_PIPE_DATA;
1128 ph->pipe_handle = pn->pipe_handle;
1129 err = pn_skb_send(sk, skb, NULL);
1131 if (err && pn_flow_safe(pn->tx_fc))
1132 atomic_inc(&pn->tx_credits);
1133 return err;
1137 static int pep_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1139 struct pep_sock *pn = pep_sk(sk);
1140 struct sk_buff *skb;
1141 long timeo;
1142 int flags = msg->msg_flags;
1143 int err, done;
1145 if (len > USHRT_MAX)
1146 return -EMSGSIZE;
1148 if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|
1149 MSG_CMSG_COMPAT)) ||
1150 !(msg->msg_flags & MSG_EOR))
1151 return -EOPNOTSUPP;
1153 skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len,
1154 flags & MSG_DONTWAIT, &err);
1155 if (!skb)
1156 return err;
1158 skb_reserve(skb, MAX_PHONET_HEADER + 3 + pn->aligned);
1159 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1160 if (err < 0)
1161 goto outfree;
1163 lock_sock(sk);
1164 timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1165 if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) {
1166 err = -ENOTCONN;
1167 goto out;
1169 if (sk->sk_state != TCP_ESTABLISHED) {
1170 /* Wait until the pipe gets to enabled state */
1171 disabled:
1172 err = sk_stream_wait_connect(sk, &timeo);
1173 if (err)
1174 goto out;
1176 if (sk->sk_state == TCP_CLOSE_WAIT) {
1177 err = -ECONNRESET;
1178 goto out;
1181 BUG_ON(sk->sk_state != TCP_ESTABLISHED);
1183 /* Wait until flow control allows TX */
1184 done = atomic_read(&pn->tx_credits);
1185 while (!done) {
1186 DEFINE_WAIT_FUNC(wait, woken_wake_function);
1188 if (!timeo) {
1189 err = -EAGAIN;
1190 goto out;
1192 if (signal_pending(current)) {
1193 err = sock_intr_errno(timeo);
1194 goto out;
1197 add_wait_queue(sk_sleep(sk), &wait);
1198 done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits), &wait);
1199 remove_wait_queue(sk_sleep(sk), &wait);
1201 if (sk->sk_state != TCP_ESTABLISHED)
1202 goto disabled;
1205 err = pipe_skb_send(sk, skb);
1206 if (err >= 0)
1207 err = len; /* success! */
1208 skb = NULL;
1209 out:
1210 release_sock(sk);
1211 outfree:
1212 kfree_skb(skb);
1213 return err;
1216 int pep_writeable(struct sock *sk)
1218 struct pep_sock *pn = pep_sk(sk);
1220 return atomic_read(&pn->tx_credits);
1223 int pep_write(struct sock *sk, struct sk_buff *skb)
1225 struct sk_buff *rskb, *fs;
1226 int flen = 0;
1228 if (pep_sk(sk)->aligned)
1229 return pipe_skb_send(sk, skb);
1231 rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC);
1232 if (!rskb) {
1233 kfree_skb(skb);
1234 return -ENOMEM;
1236 skb_shinfo(rskb)->frag_list = skb;
1237 rskb->len += skb->len;
1238 rskb->data_len += rskb->len;
1239 rskb->truesize += rskb->len;
1241 /* Avoid nested fragments */
1242 skb_walk_frags(skb, fs)
1243 flen += fs->len;
1244 skb->next = skb_shinfo(skb)->frag_list;
1245 skb_frag_list_init(skb);
1246 skb->len -= flen;
1247 skb->data_len -= flen;
1248 skb->truesize -= flen;
1250 skb_reserve(rskb, MAX_PHONET_HEADER + 3);
1251 return pipe_skb_send(sk, rskb);
1254 struct sk_buff *pep_read(struct sock *sk)
1256 struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue);
1258 if (sk->sk_state == TCP_ESTABLISHED)
1259 pipe_grant_credits(sk, GFP_ATOMIC);
1260 return skb;
1263 static int pep_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
1264 int flags, int *addr_len)
1266 struct sk_buff *skb;
1267 int err;
1269 if (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL|
1270 MSG_NOSIGNAL|MSG_CMSG_COMPAT))
1271 return -EOPNOTSUPP;
1273 if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE)))
1274 return -ENOTCONN;
1276 if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) {
1277 /* Dequeue and acknowledge control request */
1278 struct pep_sock *pn = pep_sk(sk);
1280 if (flags & MSG_PEEK)
1281 return -EOPNOTSUPP;
1282 skb = skb_dequeue(&pn->ctrlreq_queue);
1283 if (skb) {
1284 pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR,
1285 GFP_KERNEL);
1286 msg->msg_flags |= MSG_OOB;
1287 goto copy;
1289 if (flags & MSG_OOB)
1290 return -EINVAL;
1293 skb = skb_recv_datagram(sk, flags, &err);
1294 lock_sock(sk);
1295 if (skb == NULL) {
1296 if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT)
1297 err = -ECONNRESET;
1298 release_sock(sk);
1299 return err;
1302 if (sk->sk_state == TCP_ESTABLISHED)
1303 pipe_grant_credits(sk, GFP_KERNEL);
1304 release_sock(sk);
1305 copy:
1306 msg->msg_flags |= MSG_EOR;
1307 if (skb->len > len)
1308 msg->msg_flags |= MSG_TRUNC;
1309 else
1310 len = skb->len;
1312 err = skb_copy_datagram_msg(skb, 0, msg, len);
1313 if (!err)
1314 err = (flags & MSG_TRUNC) ? skb->len : len;
1316 skb_free_datagram(sk, skb);
1317 return err;
1320 static void pep_sock_unhash(struct sock *sk)
1322 struct pep_sock *pn = pep_sk(sk);
1323 struct sock *skparent = NULL;
1325 lock_sock(sk);
1327 if (pn->listener != NULL) {
1328 skparent = pn->listener;
1329 pn->listener = NULL;
1330 release_sock(sk);
1332 pn = pep_sk(skparent);
1333 lock_sock(skparent);
1334 sk_del_node_init(sk);
1335 sk = skparent;
1338 /* Unhash a listening sock only when it is closed
1339 * and all of its active connected pipes are closed. */
1340 if (hlist_empty(&pn->hlist))
1341 pn_sock_unhash(&pn->pn_sk.sk);
1342 release_sock(sk);
1344 if (skparent)
1345 sock_put(skparent);
1348 static struct proto pep_proto = {
1349 .close = pep_sock_close,
1350 .accept = pep_sock_accept,
1351 .connect = pep_sock_connect,
1352 .ioctl = pep_ioctl,
1353 .init = pep_init,
1354 .setsockopt = pep_setsockopt,
1355 .getsockopt = pep_getsockopt,
1356 .sendmsg = pep_sendmsg,
1357 .recvmsg = pep_recvmsg,
1358 .backlog_rcv = pep_do_rcv,
1359 .hash = pn_sock_hash,
1360 .unhash = pep_sock_unhash,
1361 .get_port = pn_sock_get_port,
1362 .obj_size = sizeof(struct pep_sock),
1363 .owner = THIS_MODULE,
1364 .name = "PNPIPE",
1367 static const struct phonet_protocol pep_pn_proto = {
1368 .ops = &phonet_stream_ops,
1369 .prot = &pep_proto,
1370 .sock_type = SOCK_SEQPACKET,
1373 static int __init pep_register(void)
1375 return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto);
1378 static void __exit pep_unregister(void)
1380 phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto);
1383 module_init(pep_register);
1384 module_exit(pep_unregister);
1385 MODULE_AUTHOR("Remi Denis-Courmont, Nokia");
1386 MODULE_DESCRIPTION("Phonet pipe protocol");
1387 MODULE_LICENSE("GPL");
1388 MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE);