1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * IUCV protocol stack for Linux on zSeries
4 *
5 * Copyright IBM Corp. 2006, 2009
6 *
7 * Author(s): Jennifer Hunt <jenhunt@us.ibm.com>
8 * Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
9 * PM functions:
10 * Ursula Braun <ursula.braun@de.ibm.com>
11 */
12
13 #define KMSG_COMPONENT "af_iucv"
14 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
15
16 #include <linux/filter.h>
17 #include <linux/module.h>
18 #include <linux/netdevice.h>
19 #include <linux/types.h>
20 #include <linux/limits.h>
21 #include <linux/list.h>
22 #include <linux/errno.h>
23 #include <linux/kernel.h>
24 #include <linux/sched/signal.h>
25 #include <linux/slab.h>
26 #include <linux/skbuff.h>
27 #include <linux/init.h>
28 #include <linux/poll.h>
29 #include <linux/security.h>
30 #include <net/sock.h>
31 #include <asm/ebcdic.h>
32 #include <asm/cpcmd.h>
33 #include <linux/kmod.h>
34
35 #include <net/iucv/af_iucv.h>
36
37 #define VERSION "1.2"
38
39 static char iucv_userid[80];
40
41 static struct proto iucv_proto = {
42 .name = "AF_IUCV",
43 .owner = THIS_MODULE,
44 .obj_size = sizeof(struct iucv_sock),
45 };
46
47 static struct iucv_interface *pr_iucv;
48 static struct iucv_handler af_iucv_handler;
49
50 /* special AF_IUCV IPRM messages */
51 static const u8 iprm_shutdown[8] =
52 {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
53
54 #define TRGCLS_SIZE sizeof_field(struct iucv_message, class)
55
56 #define __iucv_sock_wait(sk, condition, timeo, ret) \
57 do { \
58 DEFINE_WAIT(__wait); \
59 long __timeo = timeo; \
60 ret = 0; \
61 prepare_to_wait(sk_sleep(sk), &__wait, TASK_INTERRUPTIBLE); \
62 while (!(condition)) { \
63 if (!__timeo) { \
64 ret = -EAGAIN; \
65 break; \
66 } \
67 if (signal_pending(current)) { \
68 ret = sock_intr_errno(__timeo); \
69 break; \
70 } \
71 release_sock(sk); \
72 __timeo = schedule_timeout(__timeo); \
73 lock_sock(sk); \
74 ret = sock_error(sk); \
75 if (ret) \
76 break; \
77 } \
78 finish_wait(sk_sleep(sk), &__wait); \
79 } while (0)
80
81 #define iucv_sock_wait(sk, condition, timeo) \
82 ({ \
83 int __ret = 0; \
84 if (!(condition)) \
85 __iucv_sock_wait(sk, condition, timeo, __ret); \
86 __ret; \
87 })
88
89 static struct sock *iucv_accept_dequeue(struct sock *parent,
90 struct socket *newsock);
91 static void iucv_sock_kill(struct sock *sk);
92 static void iucv_sock_close(struct sock *sk);
93
94 static void afiucv_hs_callback_txnotify(struct sock *sk, enum iucv_tx_notify);
95
96 static struct iucv_sock_list iucv_sk_list = {
97 .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
98 .autobind_name = ATOMIC_INIT(0)
99 };
100
high_nmcpy(unsigned char * dst,char * src)101 static inline void high_nmcpy(unsigned char *dst, char *src)
102 {
103 memcpy(dst, src, 8);
104 }
105
low_nmcpy(unsigned char * dst,char * src)106 static inline void low_nmcpy(unsigned char *dst, char *src)
107 {
108 memcpy(&dst[8], src, 8);
109 }
110
111 /**
112 * iucv_msg_length() - Returns the length of an iucv message.
113 * @msg: Pointer to struct iucv_message, MUST NOT be NULL
114 *
115 * The function returns the length of the specified iucv message @msg of data
116 * stored in a buffer and of data stored in the parameter list (PRMDATA).
117 *
118 * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
119 * data:
120 * PRMDATA[0..6] socket data (max 7 bytes);
121 * PRMDATA[7] socket data length value (len is 0xff - PRMDATA[7])
122 *
123 * The socket data length is computed by subtracting the socket data length
124 * value from 0xFF.
125 * If the socket data len is greater 7, then PRMDATA can be used for special
126 * notifications (see iucv_sock_shutdown); and further,
127 * if the socket data len is > 7, the function returns 8.
128 *
129 * Use this function to allocate socket buffers to store iucv message data.
130 */
iucv_msg_length(struct iucv_message * msg)131 static inline size_t iucv_msg_length(struct iucv_message *msg)
132 {
133 size_t datalen;
134
135 if (msg->flags & IUCV_IPRMDATA) {
136 datalen = 0xff - msg->rmmsg[7];
137 return (datalen < 8) ? datalen : 8;
138 }
139 return msg->length;
140 }
141
142 /**
143 * iucv_sock_in_state() - check for specific states
144 * @sk: sock structure
145 * @state: first iucv sk state
146 * @state2: second iucv sk state
147 *
148 * Returns true if the socket in either in the first or second state.
149 */
iucv_sock_in_state(struct sock * sk,int state,int state2)150 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
151 {
152 return (sk->sk_state == state || sk->sk_state == state2);
153 }
154
155 /**
156 * iucv_below_msglim() - function to check if messages can be sent
157 * @sk: sock structure
158 *
159 * Returns true if the send queue length is lower than the message limit.
160 * Always returns true if the socket is not connected (no iucv path for
161 * checking the message limit).
162 */
iucv_below_msglim(struct sock * sk)163 static inline int iucv_below_msglim(struct sock *sk)
164 {
165 struct iucv_sock *iucv = iucv_sk(sk);
166
167 if (sk->sk_state != IUCV_CONNECTED)
168 return 1;
169 if (iucv->transport == AF_IUCV_TRANS_IUCV)
170 return (atomic_read(&iucv->skbs_in_xmit) < iucv->path->msglim);
171 else
172 return ((atomic_read(&iucv->msg_sent) < iucv->msglimit_peer) &&
173 (atomic_read(&iucv->pendings) <= 0));
174 }
175
176 /*
177 * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
178 */
iucv_sock_wake_msglim(struct sock * sk)179 static void iucv_sock_wake_msglim(struct sock *sk)
180 {
181 struct socket_wq *wq;
182
183 rcu_read_lock();
184 wq = rcu_dereference(sk->sk_wq);
185 if (skwq_has_sleeper(wq))
186 wake_up_interruptible_all(&wq->wait);
187 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
188 rcu_read_unlock();
189 }
190
191 /*
192 * afiucv_hs_send() - send a message through HiperSockets transport
193 */
afiucv_hs_send(struct iucv_message * imsg,struct sock * sock,struct sk_buff * skb,u8 flags)194 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
195 struct sk_buff *skb, u8 flags)
196 {
197 struct iucv_sock *iucv = iucv_sk(sock);
198 struct af_iucv_trans_hdr *phs_hdr;
199 int err, confirm_recv = 0;
200
201 phs_hdr = skb_push(skb, sizeof(*phs_hdr));
202 memset(phs_hdr, 0, sizeof(*phs_hdr));
203 skb_reset_network_header(skb);
204
205 phs_hdr->magic = ETH_P_AF_IUCV;
206 phs_hdr->version = 1;
207 phs_hdr->flags = flags;
208 if (flags == AF_IUCV_FLAG_SYN)
209 phs_hdr->window = iucv->msglimit;
210 else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
211 confirm_recv = atomic_read(&iucv->msg_recv);
212 phs_hdr->window = confirm_recv;
213 if (confirm_recv)
214 phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
215 }
216 memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
217 memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
218 memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
219 memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
220 ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
221 ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
222 ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
223 ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
224 if (imsg)
225 memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
226
227 skb->dev = iucv->hs_dev;
228 if (!skb->dev) {
229 err = -ENODEV;
230 goto err_free;
231 }
232
233 dev_hard_header(skb, skb->dev, ETH_P_AF_IUCV, NULL, NULL, skb->len);
234
235 if (!(skb->dev->flags & IFF_UP) || !netif_carrier_ok(skb->dev)) {
236 err = -ENETDOWN;
237 goto err_free;
238 }
239 if (skb->len > skb->dev->mtu) {
240 if (sock->sk_type == SOCK_SEQPACKET) {
241 err = -EMSGSIZE;
242 goto err_free;
243 }
244 err = pskb_trim(skb, skb->dev->mtu);
245 if (err)
246 goto err_free;
247 }
248 skb->protocol = cpu_to_be16(ETH_P_AF_IUCV);
249
250 atomic_inc(&iucv->skbs_in_xmit);
251 err = dev_queue_xmit(skb);
252 if (net_xmit_eval(err)) {
253 atomic_dec(&iucv->skbs_in_xmit);
254 } else {
255 atomic_sub(confirm_recv, &iucv->msg_recv);
256 WARN_ON(atomic_read(&iucv->msg_recv) < 0);
257 }
258 return net_xmit_eval(err);
259
260 err_free:
261 kfree_skb(skb);
262 return err;
263 }
264
__iucv_get_sock_by_name(char * nm)265 static struct sock *__iucv_get_sock_by_name(char *nm)
266 {
267 struct sock *sk;
268
269 sk_for_each(sk, &iucv_sk_list.head)
270 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
271 return sk;
272
273 return NULL;
274 }
275
iucv_sock_destruct(struct sock * sk)276 static void iucv_sock_destruct(struct sock *sk)
277 {
278 skb_queue_purge(&sk->sk_receive_queue);
279 skb_queue_purge(&sk->sk_error_queue);
280
281 if (!sock_flag(sk, SOCK_DEAD)) {
282 pr_err("Attempt to release alive iucv socket %p\n", sk);
283 return;
284 }
285
286 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
287 WARN_ON(refcount_read(&sk->sk_wmem_alloc));
288 WARN_ON(sk->sk_wmem_queued);
289 WARN_ON(sk->sk_forward_alloc);
290 }
291
292 /* Cleanup Listen */
iucv_sock_cleanup_listen(struct sock * parent)293 static void iucv_sock_cleanup_listen(struct sock *parent)
294 {
295 struct sock *sk;
296
297 /* Close non-accepted connections */
298 while ((sk = iucv_accept_dequeue(parent, NULL))) {
299 iucv_sock_close(sk);
300 iucv_sock_kill(sk);
301 }
302
303 parent->sk_state = IUCV_CLOSED;
304 }
305
iucv_sock_link(struct iucv_sock_list * l,struct sock * sk)306 static void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
307 {
308 write_lock_bh(&l->lock);
309 sk_add_node(sk, &l->head);
310 write_unlock_bh(&l->lock);
311 }
312
iucv_sock_unlink(struct iucv_sock_list * l,struct sock * sk)313 static void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
314 {
315 write_lock_bh(&l->lock);
316 sk_del_node_init(sk);
317 write_unlock_bh(&l->lock);
318 }
319
320 /* Kill socket (only if zapped and orphaned) */
iucv_sock_kill(struct sock * sk)321 static void iucv_sock_kill(struct sock *sk)
322 {
323 if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
324 return;
325
326 iucv_sock_unlink(&iucv_sk_list, sk);
327 sock_set_flag(sk, SOCK_DEAD);
328 sock_put(sk);
329 }
330
331 /* Terminate an IUCV path */
iucv_sever_path(struct sock * sk,int with_user_data)332 static void iucv_sever_path(struct sock *sk, int with_user_data)
333 {
334 unsigned char user_data[16];
335 struct iucv_sock *iucv = iucv_sk(sk);
336 struct iucv_path *path = iucv->path;
337
338 /* Whoever resets the path pointer, must sever and free it. */
339 if (xchg(&iucv->path, NULL)) {
340 if (with_user_data) {
341 low_nmcpy(user_data, iucv->src_name);
342 high_nmcpy(user_data, iucv->dst_name);
343 ASCEBC(user_data, sizeof(user_data));
344 pr_iucv->path_sever(path, user_data);
345 } else
346 pr_iucv->path_sever(path, NULL);
347 iucv_path_free(path);
348 }
349 }
350
351 /* Send controlling flags through an IUCV socket for HIPER transport */
iucv_send_ctrl(struct sock * sk,u8 flags)352 static int iucv_send_ctrl(struct sock *sk, u8 flags)
353 {
354 struct iucv_sock *iucv = iucv_sk(sk);
355 int err = 0;
356 int blen;
357 struct sk_buff *skb;
358 u8 shutdown = 0;
359
360 blen = sizeof(struct af_iucv_trans_hdr) +
361 LL_RESERVED_SPACE(iucv->hs_dev);
362 if (sk->sk_shutdown & SEND_SHUTDOWN) {
363 /* controlling flags should be sent anyway */
364 shutdown = sk->sk_shutdown;
365 sk->sk_shutdown &= RCV_SHUTDOWN;
366 }
367 skb = sock_alloc_send_skb(sk, blen, 1, &err);
368 if (skb) {
369 skb_reserve(skb, blen);
370 err = afiucv_hs_send(NULL, sk, skb, flags);
371 }
372 if (shutdown)
373 sk->sk_shutdown = shutdown;
374 return err;
375 }
376
377 /* Close an IUCV socket */
iucv_sock_close(struct sock * sk)378 static void iucv_sock_close(struct sock *sk)
379 {
380 struct iucv_sock *iucv = iucv_sk(sk);
381 unsigned long timeo;
382 int err = 0;
383
384 lock_sock(sk);
385
386 switch (sk->sk_state) {
387 case IUCV_LISTEN:
388 iucv_sock_cleanup_listen(sk);
389 break;
390
391 case IUCV_CONNECTED:
392 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
393 err = iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
394 sk->sk_state = IUCV_DISCONN;
395 sk->sk_state_change(sk);
396 }
397 fallthrough;
398
399 case IUCV_DISCONN:
400 sk->sk_state = IUCV_CLOSING;
401 sk->sk_state_change(sk);
402
403 if (!err && atomic_read(&iucv->skbs_in_xmit) > 0) {
404 if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
405 timeo = sk->sk_lingertime;
406 else
407 timeo = IUCV_DISCONN_TIMEOUT;
408 iucv_sock_wait(sk,
409 iucv_sock_in_state(sk, IUCV_CLOSED, 0),
410 timeo);
411 }
412 fallthrough;
413
414 case IUCV_CLOSING:
415 sk->sk_state = IUCV_CLOSED;
416 sk->sk_state_change(sk);
417
418 sk->sk_err = ECONNRESET;
419 sk->sk_state_change(sk);
420
421 skb_queue_purge(&iucv->send_skb_q);
422 skb_queue_purge(&iucv->backlog_skb_q);
423 fallthrough;
424
425 default:
426 iucv_sever_path(sk, 1);
427 }
428
429 if (iucv->hs_dev) {
430 dev_put(iucv->hs_dev);
431 iucv->hs_dev = NULL;
432 sk->sk_bound_dev_if = 0;
433 }
434
435 /* mark socket for deletion by iucv_sock_kill() */
436 sock_set_flag(sk, SOCK_ZAPPED);
437
438 release_sock(sk);
439 }
440
iucv_sock_init(struct sock * sk,struct sock * parent)441 static void iucv_sock_init(struct sock *sk, struct sock *parent)
442 {
443 if (parent) {
444 sk->sk_type = parent->sk_type;
445 security_sk_clone(parent, sk);
446 }
447 }
448
iucv_sock_alloc(struct socket * sock,int proto,gfp_t prio,int kern)449 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio, int kern)
450 {
451 struct sock *sk;
452 struct iucv_sock *iucv;
453
454 sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto, kern);
455 if (!sk)
456 return NULL;
457 iucv = iucv_sk(sk);
458
459 sock_init_data(sock, sk);
460 INIT_LIST_HEAD(&iucv->accept_q);
461 spin_lock_init(&iucv->accept_q_lock);
462 skb_queue_head_init(&iucv->send_skb_q);
463 INIT_LIST_HEAD(&iucv->message_q.list);
464 spin_lock_init(&iucv->message_q.lock);
465 skb_queue_head_init(&iucv->backlog_skb_q);
466 iucv->send_tag = 0;
467 atomic_set(&iucv->pendings, 0);
468 iucv->flags = 0;
469 iucv->msglimit = 0;
470 atomic_set(&iucv->skbs_in_xmit, 0);
471 atomic_set(&iucv->msg_sent, 0);
472 atomic_set(&iucv->msg_recv, 0);
473 iucv->path = NULL;
474 iucv->sk_txnotify = afiucv_hs_callback_txnotify;
475 memset(&iucv->init, 0, sizeof(iucv->init));
476 if (pr_iucv)
477 iucv->transport = AF_IUCV_TRANS_IUCV;
478 else
479 iucv->transport = AF_IUCV_TRANS_HIPER;
480
481 sk->sk_destruct = iucv_sock_destruct;
482 sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
483
484 sock_reset_flag(sk, SOCK_ZAPPED);
485
486 sk->sk_protocol = proto;
487 sk->sk_state = IUCV_OPEN;
488
489 iucv_sock_link(&iucv_sk_list, sk);
490 return sk;
491 }
492
iucv_accept_enqueue(struct sock * parent,struct sock * sk)493 static void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
494 {
495 unsigned long flags;
496 struct iucv_sock *par = iucv_sk(parent);
497
498 sock_hold(sk);
499 spin_lock_irqsave(&par->accept_q_lock, flags);
500 list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
501 spin_unlock_irqrestore(&par->accept_q_lock, flags);
502 iucv_sk(sk)->parent = parent;
503 sk_acceptq_added(parent);
504 }
505
iucv_accept_unlink(struct sock * sk)506 static void iucv_accept_unlink(struct sock *sk)
507 {
508 unsigned long flags;
509 struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
510
511 spin_lock_irqsave(&par->accept_q_lock, flags);
512 list_del_init(&iucv_sk(sk)->accept_q);
513 spin_unlock_irqrestore(&par->accept_q_lock, flags);
514 sk_acceptq_removed(iucv_sk(sk)->parent);
515 iucv_sk(sk)->parent = NULL;
516 sock_put(sk);
517 }
518
iucv_accept_dequeue(struct sock * parent,struct socket * newsock)519 static struct sock *iucv_accept_dequeue(struct sock *parent,
520 struct socket *newsock)
521 {
522 struct iucv_sock *isk, *n;
523 struct sock *sk;
524
525 list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
526 sk = (struct sock *) isk;
527 lock_sock(sk);
528
529 if (sk->sk_state == IUCV_CLOSED) {
530 iucv_accept_unlink(sk);
531 release_sock(sk);
532 continue;
533 }
534
535 if (sk->sk_state == IUCV_CONNECTED ||
536 sk->sk_state == IUCV_DISCONN ||
537 !newsock) {
538 iucv_accept_unlink(sk);
539 if (newsock)
540 sock_graft(sk, newsock);
541
542 release_sock(sk);
543 return sk;
544 }
545
546 release_sock(sk);
547 }
548 return NULL;
549 }
550
__iucv_auto_name(struct iucv_sock * iucv)551 static void __iucv_auto_name(struct iucv_sock *iucv)
552 {
553 char name[12];
554
555 sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
556 while (__iucv_get_sock_by_name(name)) {
557 sprintf(name, "%08x",
558 atomic_inc_return(&iucv_sk_list.autobind_name));
559 }
560 memcpy(iucv->src_name, name, 8);
561 }
562
563 /* Bind an unbound socket */
iucv_sock_bind(struct socket * sock,struct sockaddr * addr,int addr_len)564 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
565 int addr_len)
566 {
567 DECLARE_SOCKADDR(struct sockaddr_iucv *, sa, addr);
568 char uid[sizeof(sa->siucv_user_id)];
569 struct sock *sk = sock->sk;
570 struct iucv_sock *iucv;
571 int err = 0;
572 struct net_device *dev;
573
574 /* Verify the input sockaddr */
575 if (addr_len < sizeof(struct sockaddr_iucv) ||
576 addr->sa_family != AF_IUCV)
577 return -EINVAL;
578
579 lock_sock(sk);
580 if (sk->sk_state != IUCV_OPEN) {
581 err = -EBADFD;
582 goto done;
583 }
584
585 write_lock_bh(&iucv_sk_list.lock);
586
587 iucv = iucv_sk(sk);
588 if (__iucv_get_sock_by_name(sa->siucv_name)) {
589 err = -EADDRINUSE;
590 goto done_unlock;
591 }
592 if (iucv->path)
593 goto done_unlock;
594
595 /* Bind the socket */
596 if (pr_iucv)
597 if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
598 goto vm_bind; /* VM IUCV transport */
599
600 /* try hiper transport */
601 memcpy(uid, sa->siucv_user_id, sizeof(uid));
602 ASCEBC(uid, 8);
603 rcu_read_lock();
604 for_each_netdev_rcu(&init_net, dev) {
605 if (!memcmp(dev->perm_addr, uid, 8)) {
606 memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
607 /* Check for uninitialized siucv_name */
608 if (strncmp(sa->siucv_name, " ", 8) == 0)
609 __iucv_auto_name(iucv);
610 else
611 memcpy(iucv->src_name, sa->siucv_name, 8);
612 sk->sk_bound_dev_if = dev->ifindex;
613 iucv->hs_dev = dev;
614 dev_hold(dev);
615 sk->sk_state = IUCV_BOUND;
616 iucv->transport = AF_IUCV_TRANS_HIPER;
617 if (!iucv->msglimit)
618 iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
619 rcu_read_unlock();
620 goto done_unlock;
621 }
622 }
623 rcu_read_unlock();
624 vm_bind:
625 if (pr_iucv) {
626 /* use local userid for backward compat */
627 memcpy(iucv->src_name, sa->siucv_name, 8);
628 memcpy(iucv->src_user_id, iucv_userid, 8);
629 sk->sk_state = IUCV_BOUND;
630 iucv->transport = AF_IUCV_TRANS_IUCV;
631 sk->sk_allocation |= GFP_DMA;
632 if (!iucv->msglimit)
633 iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
634 goto done_unlock;
635 }
636 /* found no dev to bind */
637 err = -ENODEV;
638 done_unlock:
639 /* Release the socket list lock */
640 write_unlock_bh(&iucv_sk_list.lock);
641 done:
642 release_sock(sk);
643 return err;
644 }
645
646 /* Automatically bind an unbound socket */
iucv_sock_autobind(struct sock * sk)647 static int iucv_sock_autobind(struct sock *sk)
648 {
649 struct iucv_sock *iucv = iucv_sk(sk);
650 int err = 0;
651
652 if (unlikely(!pr_iucv))
653 return -EPROTO;
654
655 memcpy(iucv->src_user_id, iucv_userid, 8);
656 iucv->transport = AF_IUCV_TRANS_IUCV;
657 sk->sk_allocation |= GFP_DMA;
658
659 write_lock_bh(&iucv_sk_list.lock);
660 __iucv_auto_name(iucv);
661 write_unlock_bh(&iucv_sk_list.lock);
662
663 if (!iucv->msglimit)
664 iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
665
666 return err;
667 }
668
afiucv_path_connect(struct socket * sock,struct sockaddr * addr)669 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
670 {
671 DECLARE_SOCKADDR(struct sockaddr_iucv *, sa, addr);
672 struct sock *sk = sock->sk;
673 struct iucv_sock *iucv = iucv_sk(sk);
674 unsigned char user_data[16];
675 int err;
676
677 high_nmcpy(user_data, sa->siucv_name);
678 low_nmcpy(user_data, iucv->src_name);
679 ASCEBC(user_data, sizeof(user_data));
680
681 /* Create path. */
682 iucv->path = iucv_path_alloc(iucv->msglimit,
683 IUCV_IPRMDATA, GFP_KERNEL);
684 if (!iucv->path) {
685 err = -ENOMEM;
686 goto done;
687 }
688 err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
689 sa->siucv_user_id, NULL, user_data,
690 sk);
691 if (err) {
692 iucv_path_free(iucv->path);
693 iucv->path = NULL;
694 switch (err) {
695 case 0x0b: /* Target communicator is not logged on */
696 err = -ENETUNREACH;
697 break;
698 case 0x0d: /* Max connections for this guest exceeded */
699 case 0x0e: /* Max connections for target guest exceeded */
700 err = -EAGAIN;
701 break;
702 case 0x0f: /* Missing IUCV authorization */
703 err = -EACCES;
704 break;
705 default:
706 err = -ECONNREFUSED;
707 break;
708 }
709 }
710 done:
711 return err;
712 }
713
714 /* Connect an unconnected socket */
iucv_sock_connect(struct socket * sock,struct sockaddr * addr,int alen,int flags)715 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
716 int alen, int flags)
717 {
718 DECLARE_SOCKADDR(struct sockaddr_iucv *, sa, addr);
719 struct sock *sk = sock->sk;
720 struct iucv_sock *iucv = iucv_sk(sk);
721 int err;
722
723 if (alen < sizeof(struct sockaddr_iucv) || addr->sa_family != AF_IUCV)
724 return -EINVAL;
725
726 if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
727 return -EBADFD;
728
729 if (sk->sk_state == IUCV_OPEN &&
730 iucv->transport == AF_IUCV_TRANS_HIPER)
731 return -EBADFD; /* explicit bind required */
732
733 if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
734 return -EINVAL;
735
736 if (sk->sk_state == IUCV_OPEN) {
737 err = iucv_sock_autobind(sk);
738 if (unlikely(err))
739 return err;
740 }
741
742 lock_sock(sk);
743
744 /* Set the destination information */
745 memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
746 memcpy(iucv->dst_name, sa->siucv_name, 8);
747
748 if (iucv->transport == AF_IUCV_TRANS_HIPER)
749 err = iucv_send_ctrl(sock->sk, AF_IUCV_FLAG_SYN);
750 else
751 err = afiucv_path_connect(sock, addr);
752 if (err)
753 goto done;
754
755 if (sk->sk_state != IUCV_CONNECTED)
756 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
757 IUCV_DISCONN),
758 sock_sndtimeo(sk, flags & O_NONBLOCK));
759
760 if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
761 err = -ECONNREFUSED;
762
763 if (err && iucv->transport == AF_IUCV_TRANS_IUCV)
764 iucv_sever_path(sk, 0);
765
766 done:
767 release_sock(sk);
768 return err;
769 }
770
771 /* Move a socket into listening state. */
iucv_sock_listen(struct socket * sock,int backlog)772 static int iucv_sock_listen(struct socket *sock, int backlog)
773 {
774 struct sock *sk = sock->sk;
775 int err;
776
777 lock_sock(sk);
778
779 err = -EINVAL;
780 if (sk->sk_state != IUCV_BOUND)
781 goto done;
782
783 if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
784 goto done;
785
786 sk->sk_max_ack_backlog = backlog;
787 sk->sk_ack_backlog = 0;
788 sk->sk_state = IUCV_LISTEN;
789 err = 0;
790
791 done:
792 release_sock(sk);
793 return err;
794 }
795
796 /* Accept a pending connection */
iucv_sock_accept(struct socket * sock,struct socket * newsock,int flags,bool kern)797 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
798 int flags, bool kern)
799 {
800 DECLARE_WAITQUEUE(wait, current);
801 struct sock *sk = sock->sk, *nsk;
802 long timeo;
803 int err = 0;
804
805 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
806
807 if (sk->sk_state != IUCV_LISTEN) {
808 err = -EBADFD;
809 goto done;
810 }
811
812 timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
813
814 /* Wait for an incoming connection */
815 add_wait_queue_exclusive(sk_sleep(sk), &wait);
816 while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
817 set_current_state(TASK_INTERRUPTIBLE);
818 if (!timeo) {
819 err = -EAGAIN;
820 break;
821 }
822
823 release_sock(sk);
824 timeo = schedule_timeout(timeo);
825 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
826
827 if (sk->sk_state != IUCV_LISTEN) {
828 err = -EBADFD;
829 break;
830 }
831
832 if (signal_pending(current)) {
833 err = sock_intr_errno(timeo);
834 break;
835 }
836 }
837
838 set_current_state(TASK_RUNNING);
839 remove_wait_queue(sk_sleep(sk), &wait);
840
841 if (err)
842 goto done;
843
844 newsock->state = SS_CONNECTED;
845
846 done:
847 release_sock(sk);
848 return err;
849 }
850
iucv_sock_getname(struct socket * sock,struct sockaddr * addr,int peer)851 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
852 int peer)
853 {
854 DECLARE_SOCKADDR(struct sockaddr_iucv *, siucv, addr);
855 struct sock *sk = sock->sk;
856 struct iucv_sock *iucv = iucv_sk(sk);
857
858 addr->sa_family = AF_IUCV;
859
860 if (peer) {
861 memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
862 memcpy(siucv->siucv_name, iucv->dst_name, 8);
863 } else {
864 memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
865 memcpy(siucv->siucv_name, iucv->src_name, 8);
866 }
867 memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
868 memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
869 memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
870
871 return sizeof(struct sockaddr_iucv);
872 }
873
874 /**
875 * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
876 * @path: IUCV path
877 * @msg: Pointer to a struct iucv_message
878 * @skb: The socket data to send, skb->len MUST BE <= 7
879 *
880 * Send the socket data in the parameter list in the iucv message
881 * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
882 * list and the socket data len at index 7 (last byte).
883 * See also iucv_msg_length().
884 *
885 * Returns the error code from the iucv_message_send() call.
886 */
iucv_send_iprm(struct iucv_path * path,struct iucv_message * msg,struct sk_buff * skb)887 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
888 struct sk_buff *skb)
889 {
890 u8 prmdata[8];
891
892 memcpy(prmdata, (void *) skb->data, skb->len);
893 prmdata[7] = 0xff - (u8) skb->len;
894 return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
895 (void *) prmdata, 8);
896 }
897
iucv_sock_sendmsg(struct socket * sock,struct msghdr * msg,size_t len)898 static int iucv_sock_sendmsg(struct socket *sock, struct msghdr *msg,
899 size_t len)
900 {
901 struct sock *sk = sock->sk;
902 struct iucv_sock *iucv = iucv_sk(sk);
903 size_t headroom = 0;
904 size_t linear;
905 struct sk_buff *skb;
906 struct iucv_message txmsg = {0};
907 struct cmsghdr *cmsg;
908 int cmsg_done;
909 long timeo;
910 char user_id[9];
911 char appl_id[9];
912 int err;
913 int noblock = msg->msg_flags & MSG_DONTWAIT;
914
915 err = sock_error(sk);
916 if (err)
917 return err;
918
919 if (msg->msg_flags & MSG_OOB)
920 return -EOPNOTSUPP;
921
922 /* SOCK_SEQPACKET: we do not support segmented records */
923 if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
924 return -EOPNOTSUPP;
925
926 lock_sock(sk);
927
928 if (sk->sk_shutdown & SEND_SHUTDOWN) {
929 err = -EPIPE;
930 goto out;
931 }
932
933 /* Return if the socket is not in connected state */
934 if (sk->sk_state != IUCV_CONNECTED) {
935 err = -ENOTCONN;
936 goto out;
937 }
938
939 /* initialize defaults */
940 cmsg_done = 0; /* check for duplicate headers */
941
942 /* iterate over control messages */
943 for_each_cmsghdr(cmsg, msg) {
944 if (!CMSG_OK(msg, cmsg)) {
945 err = -EINVAL;
946 goto out;
947 }
948
949 if (cmsg->cmsg_level != SOL_IUCV)
950 continue;
951
952 if (cmsg->cmsg_type & cmsg_done) {
953 err = -EINVAL;
954 goto out;
955 }
956 cmsg_done |= cmsg->cmsg_type;
957
958 switch (cmsg->cmsg_type) {
959 case SCM_IUCV_TRGCLS:
960 if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
961 err = -EINVAL;
962 goto out;
963 }
964
965 /* set iucv message target class */
966 memcpy(&txmsg.class,
967 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
968
969 break;
970
971 default:
972 err = -EINVAL;
973 goto out;
974 }
975 }
976
977 /* allocate one skb for each iucv message:
978 * this is fine for SOCK_SEQPACKET (unless we want to support
979 * segmented records using the MSG_EOR flag), but
980 * for SOCK_STREAM we might want to improve it in future */
981 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
982 headroom = sizeof(struct af_iucv_trans_hdr) +
983 LL_RESERVED_SPACE(iucv->hs_dev);
984 linear = min(len, PAGE_SIZE - headroom);
985 } else {
986 if (len < PAGE_SIZE) {
987 linear = len;
988 } else {
989 /* In nonlinear "classic" iucv skb,
990 * reserve space for iucv_array
991 */
992 headroom = sizeof(struct iucv_array) *
993 (MAX_SKB_FRAGS + 1);
994 linear = PAGE_SIZE - headroom;
995 }
996 }
997 skb = sock_alloc_send_pskb(sk, headroom + linear, len - linear,
998 noblock, &err, 0);
999 if (!skb)
1000 goto out;
1001 if (headroom)
1002 skb_reserve(skb, headroom);
1003 skb_put(skb, linear);
1004 skb->len = len;
1005 skb->data_len = len - linear;
1006 err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, len);
1007 if (err)
1008 goto fail;
1009
1010 /* wait if outstanding messages for iucv path has reached */
1011 timeo = sock_sndtimeo(sk, noblock);
1012 err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1013 if (err)
1014 goto fail;
1015
1016 /* return -ECONNRESET if the socket is no longer connected */
1017 if (sk->sk_state != IUCV_CONNECTED) {
1018 err = -ECONNRESET;
1019 goto fail;
1020 }
1021
1022 /* increment and save iucv message tag for msg_completion cbk */
1023 txmsg.tag = iucv->send_tag++;
1024 IUCV_SKB_CB(skb)->tag = txmsg.tag;
1025
1026 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1027 atomic_inc(&iucv->msg_sent);
1028 err = afiucv_hs_send(&txmsg, sk, skb, 0);
1029 if (err) {
1030 atomic_dec(&iucv->msg_sent);
1031 goto out;
1032 }
1033 } else { /* Classic VM IUCV transport */
1034 skb_queue_tail(&iucv->send_skb_q, skb);
1035 atomic_inc(&iucv->skbs_in_xmit);
1036
1037 if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags) &&
1038 skb->len <= 7) {
1039 err = iucv_send_iprm(iucv->path, &txmsg, skb);
1040
1041 /* on success: there is no message_complete callback */
1042 /* for an IPRMDATA msg; remove skb from send queue */
1043 if (err == 0) {
1044 atomic_dec(&iucv->skbs_in_xmit);
1045 skb_unlink(skb, &iucv->send_skb_q);
1046 consume_skb(skb);
1047 }
1048
1049 /* this error should never happen since the */
1050 /* IUCV_IPRMDATA path flag is set... sever path */
1051 if (err == 0x15) {
1052 pr_iucv->path_sever(iucv->path, NULL);
1053 atomic_dec(&iucv->skbs_in_xmit);
1054 skb_unlink(skb, &iucv->send_skb_q);
1055 err = -EPIPE;
1056 goto fail;
1057 }
1058 } else if (skb_is_nonlinear(skb)) {
1059 struct iucv_array *iba = (struct iucv_array *)skb->head;
1060 int i;
1061
1062 /* skip iucv_array lying in the headroom */
1063 iba[0].address = (u32)(addr_t)skb->data;
1064 iba[0].length = (u32)skb_headlen(skb);
1065 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1066 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1067
1068 iba[i + 1].address =
1069 (u32)(addr_t)skb_frag_address(frag);
1070 iba[i + 1].length = (u32)skb_frag_size(frag);
1071 }
1072 err = pr_iucv->message_send(iucv->path, &txmsg,
1073 IUCV_IPBUFLST, 0,
1074 (void *)iba, skb->len);
1075 } else { /* non-IPRM Linear skb */
1076 err = pr_iucv->message_send(iucv->path, &txmsg,
1077 0, 0, (void *)skb->data, skb->len);
1078 }
1079 if (err) {
1080 if (err == 3) {
1081 user_id[8] = 0;
1082 memcpy(user_id, iucv->dst_user_id, 8);
1083 appl_id[8] = 0;
1084 memcpy(appl_id, iucv->dst_name, 8);
1085 pr_err(
1086 "Application %s on z/VM guest %s exceeds message limit\n",
1087 appl_id, user_id);
1088 err = -EAGAIN;
1089 } else {
1090 err = -EPIPE;
1091 }
1092
1093 atomic_dec(&iucv->skbs_in_xmit);
1094 skb_unlink(skb, &iucv->send_skb_q);
1095 goto fail;
1096 }
1097 }
1098
1099 release_sock(sk);
1100 return len;
1101
1102 fail:
1103 kfree_skb(skb);
1104 out:
1105 release_sock(sk);
1106 return err;
1107 }
1108
alloc_iucv_recv_skb(unsigned long len)1109 static struct sk_buff *alloc_iucv_recv_skb(unsigned long len)
1110 {
1111 size_t headroom, linear;
1112 struct sk_buff *skb;
1113 int err;
1114
1115 if (len < PAGE_SIZE) {
1116 headroom = 0;
1117 linear = len;
1118 } else {
1119 headroom = sizeof(struct iucv_array) * (MAX_SKB_FRAGS + 1);
1120 linear = PAGE_SIZE - headroom;
1121 }
1122 skb = alloc_skb_with_frags(headroom + linear, len - linear,
1123 0, &err, GFP_ATOMIC | GFP_DMA);
1124 WARN_ONCE(!skb,
1125 "alloc of recv iucv skb len=%lu failed with errcode=%d\n",
1126 len, err);
1127 if (skb) {
1128 if (headroom)
1129 skb_reserve(skb, headroom);
1130 skb_put(skb, linear);
1131 skb->len = len;
1132 skb->data_len = len - linear;
1133 }
1134 return skb;
1135 }
1136
1137 /* iucv_process_message() - Receive a single outstanding IUCV message
1138 *
1139 * Locking: must be called with message_q.lock held
1140 */
iucv_process_message(struct sock * sk,struct sk_buff * skb,struct iucv_path * path,struct iucv_message * msg)1141 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1142 struct iucv_path *path,
1143 struct iucv_message *msg)
1144 {
1145 int rc;
1146 unsigned int len;
1147
1148 len = iucv_msg_length(msg);
1149
1150 /* store msg target class in the second 4 bytes of skb ctrl buffer */
1151 /* Note: the first 4 bytes are reserved for msg tag */
1152 IUCV_SKB_CB(skb)->class = msg->class;
1153
1154 /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1155 if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1156 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1157 skb->data = NULL;
1158 skb->len = 0;
1159 }
1160 } else {
1161 if (skb_is_nonlinear(skb)) {
1162 struct iucv_array *iba = (struct iucv_array *)skb->head;
1163 int i;
1164
1165 iba[0].address = (u32)(addr_t)skb->data;
1166 iba[0].length = (u32)skb_headlen(skb);
1167 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1168 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1169
1170 iba[i + 1].address =
1171 (u32)(addr_t)skb_frag_address(frag);
1172 iba[i + 1].length = (u32)skb_frag_size(frag);
1173 }
1174 rc = pr_iucv->message_receive(path, msg,
1175 IUCV_IPBUFLST,
1176 (void *)iba, len, NULL);
1177 } else {
1178 rc = pr_iucv->message_receive(path, msg,
1179 msg->flags & IUCV_IPRMDATA,
1180 skb->data, len, NULL);
1181 }
1182 if (rc) {
1183 kfree_skb(skb);
1184 return;
1185 }
1186 WARN_ON_ONCE(skb->len != len);
1187 }
1188
1189 IUCV_SKB_CB(skb)->offset = 0;
1190 if (sk_filter(sk, skb)) {
1191 atomic_inc(&sk->sk_drops); /* skb rejected by filter */
1192 kfree_skb(skb);
1193 return;
1194 }
1195 if (__sock_queue_rcv_skb(sk, skb)) /* handle rcv queue full */
1196 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
1197 }
1198
1199 /* iucv_process_message_q() - Process outstanding IUCV messages
1200 *
1201 * Locking: must be called with message_q.lock held
1202 */
iucv_process_message_q(struct sock * sk)1203 static void iucv_process_message_q(struct sock *sk)
1204 {
1205 struct iucv_sock *iucv = iucv_sk(sk);
1206 struct sk_buff *skb;
1207 struct sock_msg_q *p, *n;
1208
1209 list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1210 skb = alloc_iucv_recv_skb(iucv_msg_length(&p->msg));
1211 if (!skb)
1212 break;
1213 iucv_process_message(sk, skb, p->path, &p->msg);
1214 list_del(&p->list);
1215 kfree(p);
1216 if (!skb_queue_empty(&iucv->backlog_skb_q))
1217 break;
1218 }
1219 }
1220
iucv_sock_recvmsg(struct socket * sock,struct msghdr * msg,size_t len,int flags)1221 static int iucv_sock_recvmsg(struct socket *sock, struct msghdr *msg,
1222 size_t len, int flags)
1223 {
1224 struct sock *sk = sock->sk;
1225 struct iucv_sock *iucv = iucv_sk(sk);
1226 unsigned int copied, rlen;
1227 struct sk_buff *skb, *rskb, *cskb;
1228 int err = 0;
1229 u32 offset;
1230
1231 if ((sk->sk_state == IUCV_DISCONN) &&
1232 skb_queue_empty(&iucv->backlog_skb_q) &&
1233 skb_queue_empty(&sk->sk_receive_queue) &&
1234 list_empty(&iucv->message_q.list))
1235 return 0;
1236
1237 if (flags & (MSG_OOB))
1238 return -EOPNOTSUPP;
1239
1240 /* receive/dequeue next skb:
1241 * the function understands MSG_PEEK and, thus, does not dequeue skb */
1242 skb = skb_recv_datagram(sk, flags, &err);
1243 if (!skb) {
1244 if (sk->sk_shutdown & RCV_SHUTDOWN)
1245 return 0;
1246 return err;
1247 }
1248
1249 offset = IUCV_SKB_CB(skb)->offset;
1250 rlen = skb->len - offset; /* real length of skb */
1251 copied = min_t(unsigned int, rlen, len);
1252 if (!rlen)
1253 sk->sk_shutdown = sk->sk_shutdown | RCV_SHUTDOWN;
1254
1255 cskb = skb;
1256 if (skb_copy_datagram_msg(cskb, offset, msg, copied)) {
1257 if (!(flags & MSG_PEEK))
1258 skb_queue_head(&sk->sk_receive_queue, skb);
1259 return -EFAULT;
1260 }
1261
1262 /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1263 if (sk->sk_type == SOCK_SEQPACKET) {
1264 if (copied < rlen)
1265 msg->msg_flags |= MSG_TRUNC;
1266 /* each iucv message contains a complete record */
1267 msg->msg_flags |= MSG_EOR;
1268 }
1269
1270 /* create control message to store iucv msg target class:
1271 * get the trgcls from the control buffer of the skb due to
1272 * fragmentation of original iucv message. */
1273 err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1274 sizeof(IUCV_SKB_CB(skb)->class),
1275 (void *)&IUCV_SKB_CB(skb)->class);
1276 if (err) {
1277 if (!(flags & MSG_PEEK))
1278 skb_queue_head(&sk->sk_receive_queue, skb);
1279 return err;
1280 }
1281
1282 /* Mark read part of skb as used */
1283 if (!(flags & MSG_PEEK)) {
1284
1285 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1286 if (sk->sk_type == SOCK_STREAM) {
1287 if (copied < rlen) {
1288 IUCV_SKB_CB(skb)->offset = offset + copied;
1289 skb_queue_head(&sk->sk_receive_queue, skb);
1290 goto done;
1291 }
1292 }
1293
1294 consume_skb(skb);
1295 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1296 atomic_inc(&iucv->msg_recv);
1297 if (atomic_read(&iucv->msg_recv) > iucv->msglimit) {
1298 WARN_ON(1);
1299 iucv_sock_close(sk);
1300 return -EFAULT;
1301 }
1302 }
1303
1304 /* Queue backlog skbs */
1305 spin_lock_bh(&iucv->message_q.lock);
1306 rskb = skb_dequeue(&iucv->backlog_skb_q);
1307 while (rskb) {
1308 IUCV_SKB_CB(rskb)->offset = 0;
1309 if (__sock_queue_rcv_skb(sk, rskb)) {
1310 /* handle rcv queue full */
1311 skb_queue_head(&iucv->backlog_skb_q,
1312 rskb);
1313 break;
1314 }
1315 rskb = skb_dequeue(&iucv->backlog_skb_q);
1316 }
1317 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1318 if (!list_empty(&iucv->message_q.list))
1319 iucv_process_message_q(sk);
1320 if (atomic_read(&iucv->msg_recv) >=
1321 iucv->msglimit / 2) {
1322 err = iucv_send_ctrl(sk, AF_IUCV_FLAG_WIN);
1323 if (err) {
1324 sk->sk_state = IUCV_DISCONN;
1325 sk->sk_state_change(sk);
1326 }
1327 }
1328 }
1329 spin_unlock_bh(&iucv->message_q.lock);
1330 }
1331
1332 done:
1333 /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1334 if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1335 copied = rlen;
1336
1337 return copied;
1338 }
1339
iucv_accept_poll(struct sock * parent)1340 static inline __poll_t iucv_accept_poll(struct sock *parent)
1341 {
1342 struct iucv_sock *isk, *n;
1343 struct sock *sk;
1344
1345 list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1346 sk = (struct sock *) isk;
1347
1348 if (sk->sk_state == IUCV_CONNECTED)
1349 return EPOLLIN | EPOLLRDNORM;
1350 }
1351
1352 return 0;
1353 }
1354
iucv_sock_poll(struct file * file,struct socket * sock,poll_table * wait)1355 static __poll_t iucv_sock_poll(struct file *file, struct socket *sock,
1356 poll_table *wait)
1357 {
1358 struct sock *sk = sock->sk;
1359 __poll_t mask = 0;
1360
1361 sock_poll_wait(file, sock, wait);
1362
1363 if (sk->sk_state == IUCV_LISTEN)
1364 return iucv_accept_poll(sk);
1365
1366 if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1367 mask |= EPOLLERR |
1368 (sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
1369
1370 if (sk->sk_shutdown & RCV_SHUTDOWN)
1371 mask |= EPOLLRDHUP;
1372
1373 if (sk->sk_shutdown == SHUTDOWN_MASK)
1374 mask |= EPOLLHUP;
1375
1376 if (!skb_queue_empty(&sk->sk_receive_queue) ||
1377 (sk->sk_shutdown & RCV_SHUTDOWN))
1378 mask |= EPOLLIN | EPOLLRDNORM;
1379
1380 if (sk->sk_state == IUCV_CLOSED)
1381 mask |= EPOLLHUP;
1382
1383 if (sk->sk_state == IUCV_DISCONN)
1384 mask |= EPOLLIN;
1385
1386 if (sock_writeable(sk) && iucv_below_msglim(sk))
1387 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
1388 else
1389 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1390
1391 return mask;
1392 }
1393
iucv_sock_shutdown(struct socket * sock,int how)1394 static int iucv_sock_shutdown(struct socket *sock, int how)
1395 {
1396 struct sock *sk = sock->sk;
1397 struct iucv_sock *iucv = iucv_sk(sk);
1398 struct iucv_message txmsg;
1399 int err = 0;
1400
1401 how++;
1402
1403 if ((how & ~SHUTDOWN_MASK) || !how)
1404 return -EINVAL;
1405
1406 lock_sock(sk);
1407 switch (sk->sk_state) {
1408 case IUCV_LISTEN:
1409 case IUCV_DISCONN:
1410 case IUCV_CLOSING:
1411 case IUCV_CLOSED:
1412 err = -ENOTCONN;
1413 goto fail;
1414 default:
1415 break;
1416 }
1417
1418 if ((how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) &&
1419 sk->sk_state == IUCV_CONNECTED) {
1420 if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1421 txmsg.class = 0;
1422 txmsg.tag = 0;
1423 err = pr_iucv->message_send(iucv->path, &txmsg,
1424 IUCV_IPRMDATA, 0, (void *) iprm_shutdown, 8);
1425 if (err) {
1426 switch (err) {
1427 case 1:
1428 err = -ENOTCONN;
1429 break;
1430 case 2:
1431 err = -ECONNRESET;
1432 break;
1433 default:
1434 err = -ENOTCONN;
1435 break;
1436 }
1437 }
1438 } else
1439 iucv_send_ctrl(sk, AF_IUCV_FLAG_SHT);
1440 }
1441
1442 sk->sk_shutdown |= how;
1443 if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1444 if ((iucv->transport == AF_IUCV_TRANS_IUCV) &&
1445 iucv->path) {
1446 err = pr_iucv->path_quiesce(iucv->path, NULL);
1447 if (err)
1448 err = -ENOTCONN;
1449 /* skb_queue_purge(&sk->sk_receive_queue); */
1450 }
1451 skb_queue_purge(&sk->sk_receive_queue);
1452 }
1453
1454 /* Wake up anyone sleeping in poll */
1455 sk->sk_state_change(sk);
1456
1457 fail:
1458 release_sock(sk);
1459 return err;
1460 }
1461
iucv_sock_release(struct socket * sock)1462 static int iucv_sock_release(struct socket *sock)
1463 {
1464 struct sock *sk = sock->sk;
1465 int err = 0;
1466
1467 if (!sk)
1468 return 0;
1469
1470 iucv_sock_close(sk);
1471
1472 sock_orphan(sk);
1473 iucv_sock_kill(sk);
1474 return err;
1475 }
1476
1477 /* getsockopt and setsockopt */
iucv_sock_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)1478 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1479 sockptr_t optval, unsigned int optlen)
1480 {
1481 struct sock *sk = sock->sk;
1482 struct iucv_sock *iucv = iucv_sk(sk);
1483 int val;
1484 int rc;
1485
1486 if (level != SOL_IUCV)
1487 return -ENOPROTOOPT;
1488
1489 if (optlen < sizeof(int))
1490 return -EINVAL;
1491
1492 if (copy_from_sockptr(&val, optval, sizeof(int)))
1493 return -EFAULT;
1494
1495 rc = 0;
1496
1497 lock_sock(sk);
1498 switch (optname) {
1499 case SO_IPRMDATA_MSG:
1500 if (val)
1501 iucv->flags |= IUCV_IPRMDATA;
1502 else
1503 iucv->flags &= ~IUCV_IPRMDATA;
1504 break;
1505 case SO_MSGLIMIT:
1506 switch (sk->sk_state) {
1507 case IUCV_OPEN:
1508 case IUCV_BOUND:
1509 if (val < 1 || val > U16_MAX)
1510 rc = -EINVAL;
1511 else
1512 iucv->msglimit = val;
1513 break;
1514 default:
1515 rc = -EINVAL;
1516 break;
1517 }
1518 break;
1519 default:
1520 rc = -ENOPROTOOPT;
1521 break;
1522 }
1523 release_sock(sk);
1524
1525 return rc;
1526 }
1527
iucv_sock_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)1528 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1529 char __user *optval, int __user *optlen)
1530 {
1531 struct sock *sk = sock->sk;
1532 struct iucv_sock *iucv = iucv_sk(sk);
1533 unsigned int val;
1534 int len;
1535
1536 if (level != SOL_IUCV)
1537 return -ENOPROTOOPT;
1538
1539 if (get_user(len, optlen))
1540 return -EFAULT;
1541
1542 if (len < 0)
1543 return -EINVAL;
1544
1545 len = min_t(unsigned int, len, sizeof(int));
1546
1547 switch (optname) {
1548 case SO_IPRMDATA_MSG:
1549 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1550 break;
1551 case SO_MSGLIMIT:
1552 lock_sock(sk);
1553 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1554 : iucv->msglimit; /* default */
1555 release_sock(sk);
1556 break;
1557 case SO_MSGSIZE:
1558 if (sk->sk_state == IUCV_OPEN)
1559 return -EBADFD;
1560 val = (iucv->hs_dev) ? iucv->hs_dev->mtu -
1561 sizeof(struct af_iucv_trans_hdr) - ETH_HLEN :
1562 0x7fffffff;
1563 break;
1564 default:
1565 return -ENOPROTOOPT;
1566 }
1567
1568 if (put_user(len, optlen))
1569 return -EFAULT;
1570 if (copy_to_user(optval, &val, len))
1571 return -EFAULT;
1572
1573 return 0;
1574 }
1575
1576
1577 /* Callback wrappers - called from iucv base support */
iucv_callback_connreq(struct iucv_path * path,u8 ipvmid[8],u8 ipuser[16])1578 static int iucv_callback_connreq(struct iucv_path *path,
1579 u8 ipvmid[8], u8 ipuser[16])
1580 {
1581 unsigned char user_data[16];
1582 unsigned char nuser_data[16];
1583 unsigned char src_name[8];
1584 struct sock *sk, *nsk;
1585 struct iucv_sock *iucv, *niucv;
1586 int err;
1587
1588 memcpy(src_name, ipuser, 8);
1589 EBCASC(src_name, 8);
1590 /* Find out if this path belongs to af_iucv. */
1591 read_lock(&iucv_sk_list.lock);
1592 iucv = NULL;
1593 sk = NULL;
1594 sk_for_each(sk, &iucv_sk_list.head)
1595 if (sk->sk_state == IUCV_LISTEN &&
1596 !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1597 /*
1598 * Found a listening socket with
1599 * src_name == ipuser[0-7].
1600 */
1601 iucv = iucv_sk(sk);
1602 break;
1603 }
1604 read_unlock(&iucv_sk_list.lock);
1605 if (!iucv)
1606 /* No socket found, not one of our paths. */
1607 return -EINVAL;
1608
1609 bh_lock_sock(sk);
1610
1611 /* Check if parent socket is listening */
1612 low_nmcpy(user_data, iucv->src_name);
1613 high_nmcpy(user_data, iucv->dst_name);
1614 ASCEBC(user_data, sizeof(user_data));
1615 if (sk->sk_state != IUCV_LISTEN) {
1616 err = pr_iucv->path_sever(path, user_data);
1617 iucv_path_free(path);
1618 goto fail;
1619 }
1620
1621 /* Check for backlog size */
1622 if (sk_acceptq_is_full(sk)) {
1623 err = pr_iucv->path_sever(path, user_data);
1624 iucv_path_free(path);
1625 goto fail;
1626 }
1627
1628 /* Create the new socket */
1629 nsk = iucv_sock_alloc(NULL, sk->sk_protocol, GFP_ATOMIC, 0);
1630 if (!nsk) {
1631 err = pr_iucv->path_sever(path, user_data);
1632 iucv_path_free(path);
1633 goto fail;
1634 }
1635
1636 niucv = iucv_sk(nsk);
1637 iucv_sock_init(nsk, sk);
1638 niucv->transport = AF_IUCV_TRANS_IUCV;
1639 nsk->sk_allocation |= GFP_DMA;
1640
1641 /* Set the new iucv_sock */
1642 memcpy(niucv->dst_name, ipuser + 8, 8);
1643 EBCASC(niucv->dst_name, 8);
1644 memcpy(niucv->dst_user_id, ipvmid, 8);
1645 memcpy(niucv->src_name, iucv->src_name, 8);
1646 memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1647 niucv->path = path;
1648
1649 /* Call iucv_accept */
1650 high_nmcpy(nuser_data, ipuser + 8);
1651 memcpy(nuser_data + 8, niucv->src_name, 8);
1652 ASCEBC(nuser_data + 8, 8);
1653
1654 /* set message limit for path based on msglimit of accepting socket */
1655 niucv->msglimit = iucv->msglimit;
1656 path->msglim = iucv->msglimit;
1657 err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1658 if (err) {
1659 iucv_sever_path(nsk, 1);
1660 iucv_sock_kill(nsk);
1661 goto fail;
1662 }
1663
1664 iucv_accept_enqueue(sk, nsk);
1665
1666 /* Wake up accept */
1667 nsk->sk_state = IUCV_CONNECTED;
1668 sk->sk_data_ready(sk);
1669 err = 0;
1670 fail:
1671 bh_unlock_sock(sk);
1672 return 0;
1673 }
1674
iucv_callback_connack(struct iucv_path * path,u8 ipuser[16])1675 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1676 {
1677 struct sock *sk = path->private;
1678
1679 sk->sk_state = IUCV_CONNECTED;
1680 sk->sk_state_change(sk);
1681 }
1682
iucv_callback_rx(struct iucv_path * path,struct iucv_message * msg)1683 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1684 {
1685 struct sock *sk = path->private;
1686 struct iucv_sock *iucv = iucv_sk(sk);
1687 struct sk_buff *skb;
1688 struct sock_msg_q *save_msg;
1689 int len;
1690
1691 if (sk->sk_shutdown & RCV_SHUTDOWN) {
1692 pr_iucv->message_reject(path, msg);
1693 return;
1694 }
1695
1696 spin_lock(&iucv->message_q.lock);
1697
1698 if (!list_empty(&iucv->message_q.list) ||
1699 !skb_queue_empty(&iucv->backlog_skb_q))
1700 goto save_message;
1701
1702 len = atomic_read(&sk->sk_rmem_alloc);
1703 len += SKB_TRUESIZE(iucv_msg_length(msg));
1704 if (len > sk->sk_rcvbuf)
1705 goto save_message;
1706
1707 skb = alloc_iucv_recv_skb(iucv_msg_length(msg));
1708 if (!skb)
1709 goto save_message;
1710
1711 iucv_process_message(sk, skb, path, msg);
1712 goto out_unlock;
1713
1714 save_message:
1715 save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1716 if (!save_msg)
1717 goto out_unlock;
1718 save_msg->path = path;
1719 save_msg->msg = *msg;
1720
1721 list_add_tail(&save_msg->list, &iucv->message_q.list);
1722
1723 out_unlock:
1724 spin_unlock(&iucv->message_q.lock);
1725 }
1726
iucv_callback_txdone(struct iucv_path * path,struct iucv_message * msg)1727 static void iucv_callback_txdone(struct iucv_path *path,
1728 struct iucv_message *msg)
1729 {
1730 struct sock *sk = path->private;
1731 struct sk_buff *this = NULL;
1732 struct sk_buff_head *list;
1733 struct sk_buff *list_skb;
1734 struct iucv_sock *iucv;
1735 unsigned long flags;
1736
1737 iucv = iucv_sk(sk);
1738 list = &iucv->send_skb_q;
1739
1740 bh_lock_sock(sk);
1741
1742 spin_lock_irqsave(&list->lock, flags);
1743 skb_queue_walk(list, list_skb) {
1744 if (msg->tag == IUCV_SKB_CB(list_skb)->tag) {
1745 this = list_skb;
1746 break;
1747 }
1748 }
1749 if (this) {
1750 atomic_dec(&iucv->skbs_in_xmit);
1751 __skb_unlink(this, list);
1752 }
1753
1754 spin_unlock_irqrestore(&list->lock, flags);
1755
1756 if (this) {
1757 consume_skb(this);
1758 /* wake up any process waiting for sending */
1759 iucv_sock_wake_msglim(sk);
1760 }
1761
1762 if (sk->sk_state == IUCV_CLOSING) {
1763 if (atomic_read(&iucv->skbs_in_xmit) == 0) {
1764 sk->sk_state = IUCV_CLOSED;
1765 sk->sk_state_change(sk);
1766 }
1767 }
1768 bh_unlock_sock(sk);
1769
1770 }
1771
iucv_callback_connrej(struct iucv_path * path,u8 ipuser[16])1772 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1773 {
1774 struct sock *sk = path->private;
1775
1776 if (sk->sk_state == IUCV_CLOSED)
1777 return;
1778
1779 bh_lock_sock(sk);
1780 iucv_sever_path(sk, 1);
1781 sk->sk_state = IUCV_DISCONN;
1782
1783 sk->sk_state_change(sk);
1784 bh_unlock_sock(sk);
1785 }
1786
1787 /* called if the other communication side shuts down its RECV direction;
1788 * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1789 */
iucv_callback_shutdown(struct iucv_path * path,u8 ipuser[16])1790 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1791 {
1792 struct sock *sk = path->private;
1793
1794 bh_lock_sock(sk);
1795 if (sk->sk_state != IUCV_CLOSED) {
1796 sk->sk_shutdown |= SEND_SHUTDOWN;
1797 sk->sk_state_change(sk);
1798 }
1799 bh_unlock_sock(sk);
1800 }
1801
1802 static struct iucv_handler af_iucv_handler = {
1803 .path_pending = iucv_callback_connreq,
1804 .path_complete = iucv_callback_connack,
1805 .path_severed = iucv_callback_connrej,
1806 .message_pending = iucv_callback_rx,
1807 .message_complete = iucv_callback_txdone,
1808 .path_quiesced = iucv_callback_shutdown,
1809 };
1810
1811 /***************** HiperSockets transport callbacks ********************/
afiucv_swap_src_dest(struct sk_buff * skb)1812 static void afiucv_swap_src_dest(struct sk_buff *skb)
1813 {
1814 struct af_iucv_trans_hdr *trans_hdr = iucv_trans_hdr(skb);
1815 char tmpID[8];
1816 char tmpName[8];
1817
1818 ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1819 ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1820 ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1821 ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1822 memcpy(tmpID, trans_hdr->srcUserID, 8);
1823 memcpy(tmpName, trans_hdr->srcAppName, 8);
1824 memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1825 memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1826 memcpy(trans_hdr->destUserID, tmpID, 8);
1827 memcpy(trans_hdr->destAppName, tmpName, 8);
1828 skb_push(skb, ETH_HLEN);
1829 memset(skb->data, 0, ETH_HLEN);
1830 }
1831
1832 /*
1833 * afiucv_hs_callback_syn - react on received SYN
1834 */
afiucv_hs_callback_syn(struct sock * sk,struct sk_buff * skb)1835 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1836 {
1837 struct af_iucv_trans_hdr *trans_hdr = iucv_trans_hdr(skb);
1838 struct sock *nsk;
1839 struct iucv_sock *iucv, *niucv;
1840 int err;
1841
1842 iucv = iucv_sk(sk);
1843 if (!iucv) {
1844 /* no sock - connection refused */
1845 afiucv_swap_src_dest(skb);
1846 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1847 err = dev_queue_xmit(skb);
1848 goto out;
1849 }
1850
1851 nsk = iucv_sock_alloc(NULL, sk->sk_protocol, GFP_ATOMIC, 0);
1852 bh_lock_sock(sk);
1853 if ((sk->sk_state != IUCV_LISTEN) ||
1854 sk_acceptq_is_full(sk) ||
1855 !nsk) {
1856 /* error on server socket - connection refused */
1857 afiucv_swap_src_dest(skb);
1858 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1859 err = dev_queue_xmit(skb);
1860 iucv_sock_kill(nsk);
1861 bh_unlock_sock(sk);
1862 goto out;
1863 }
1864
1865 niucv = iucv_sk(nsk);
1866 iucv_sock_init(nsk, sk);
1867 niucv->transport = AF_IUCV_TRANS_HIPER;
1868 niucv->msglimit = iucv->msglimit;
1869 if (!trans_hdr->window)
1870 niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
1871 else
1872 niucv->msglimit_peer = trans_hdr->window;
1873 memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
1874 memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
1875 memcpy(niucv->src_name, iucv->src_name, 8);
1876 memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1877 nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
1878 niucv->hs_dev = iucv->hs_dev;
1879 dev_hold(niucv->hs_dev);
1880 afiucv_swap_src_dest(skb);
1881 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
1882 trans_hdr->window = niucv->msglimit;
1883 /* if receiver acks the xmit connection is established */
1884 err = dev_queue_xmit(skb);
1885 if (!err) {
1886 iucv_accept_enqueue(sk, nsk);
1887 nsk->sk_state = IUCV_CONNECTED;
1888 sk->sk_data_ready(sk);
1889 } else
1890 iucv_sock_kill(nsk);
1891 bh_unlock_sock(sk);
1892
1893 out:
1894 return NET_RX_SUCCESS;
1895 }
1896
1897 /*
1898 * afiucv_hs_callback_synack() - react on received SYN-ACK
1899 */
afiucv_hs_callback_synack(struct sock * sk,struct sk_buff * skb)1900 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
1901 {
1902 struct iucv_sock *iucv = iucv_sk(sk);
1903
1904 if (!iucv || sk->sk_state != IUCV_BOUND) {
1905 kfree_skb(skb);
1906 return NET_RX_SUCCESS;
1907 }
1908
1909 bh_lock_sock(sk);
1910 iucv->msglimit_peer = iucv_trans_hdr(skb)->window;
1911 sk->sk_state = IUCV_CONNECTED;
1912 sk->sk_state_change(sk);
1913 bh_unlock_sock(sk);
1914 consume_skb(skb);
1915 return NET_RX_SUCCESS;
1916 }
1917
1918 /*
1919 * afiucv_hs_callback_synfin() - react on received SYN_FIN
1920 */
afiucv_hs_callback_synfin(struct sock * sk,struct sk_buff * skb)1921 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
1922 {
1923 struct iucv_sock *iucv = iucv_sk(sk);
1924
1925 if (!iucv || sk->sk_state != IUCV_BOUND) {
1926 kfree_skb(skb);
1927 return NET_RX_SUCCESS;
1928 }
1929
1930 bh_lock_sock(sk);
1931 sk->sk_state = IUCV_DISCONN;
1932 sk->sk_state_change(sk);
1933 bh_unlock_sock(sk);
1934 consume_skb(skb);
1935 return NET_RX_SUCCESS;
1936 }
1937
1938 /*
1939 * afiucv_hs_callback_fin() - react on received FIN
1940 */
afiucv_hs_callback_fin(struct sock * sk,struct sk_buff * skb)1941 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
1942 {
1943 struct iucv_sock *iucv = iucv_sk(sk);
1944
1945 /* other end of connection closed */
1946 if (!iucv) {
1947 kfree_skb(skb);
1948 return NET_RX_SUCCESS;
1949 }
1950
1951 bh_lock_sock(sk);
1952 if (sk->sk_state == IUCV_CONNECTED) {
1953 sk->sk_state = IUCV_DISCONN;
1954 sk->sk_state_change(sk);
1955 }
1956 bh_unlock_sock(sk);
1957 consume_skb(skb);
1958 return NET_RX_SUCCESS;
1959 }
1960
1961 /*
1962 * afiucv_hs_callback_win() - react on received WIN
1963 */
afiucv_hs_callback_win(struct sock * sk,struct sk_buff * skb)1964 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
1965 {
1966 struct iucv_sock *iucv = iucv_sk(sk);
1967
1968 if (!iucv)
1969 return NET_RX_SUCCESS;
1970
1971 if (sk->sk_state != IUCV_CONNECTED)
1972 return NET_RX_SUCCESS;
1973
1974 atomic_sub(iucv_trans_hdr(skb)->window, &iucv->msg_sent);
1975 iucv_sock_wake_msglim(sk);
1976 return NET_RX_SUCCESS;
1977 }
1978
1979 /*
1980 * afiucv_hs_callback_rx() - react on received data
1981 */
afiucv_hs_callback_rx(struct sock * sk,struct sk_buff * skb)1982 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
1983 {
1984 struct iucv_sock *iucv = iucv_sk(sk);
1985
1986 if (!iucv) {
1987 kfree_skb(skb);
1988 return NET_RX_SUCCESS;
1989 }
1990
1991 if (sk->sk_state != IUCV_CONNECTED) {
1992 kfree_skb(skb);
1993 return NET_RX_SUCCESS;
1994 }
1995
1996 if (sk->sk_shutdown & RCV_SHUTDOWN) {
1997 kfree_skb(skb);
1998 return NET_RX_SUCCESS;
1999 }
2000
2001 /* write stuff from iucv_msg to skb cb */
2002 skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2003 skb_reset_transport_header(skb);
2004 skb_reset_network_header(skb);
2005 IUCV_SKB_CB(skb)->offset = 0;
2006 if (sk_filter(sk, skb)) {
2007 atomic_inc(&sk->sk_drops); /* skb rejected by filter */
2008 kfree_skb(skb);
2009 return NET_RX_SUCCESS;
2010 }
2011
2012 spin_lock(&iucv->message_q.lock);
2013 if (skb_queue_empty(&iucv->backlog_skb_q)) {
2014 if (__sock_queue_rcv_skb(sk, skb))
2015 /* handle rcv queue full */
2016 skb_queue_tail(&iucv->backlog_skb_q, skb);
2017 } else
2018 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2019 spin_unlock(&iucv->message_q.lock);
2020 return NET_RX_SUCCESS;
2021 }
2022
2023 /*
2024 * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2025 * transport
2026 * called from netif RX softirq
2027 */
afiucv_hs_rcv(struct sk_buff * skb,struct net_device * dev,struct packet_type * pt,struct net_device * orig_dev)2028 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2029 struct packet_type *pt, struct net_device *orig_dev)
2030 {
2031 struct sock *sk;
2032 struct iucv_sock *iucv;
2033 struct af_iucv_trans_hdr *trans_hdr;
2034 int err = NET_RX_SUCCESS;
2035 char nullstring[8];
2036
2037 if (!pskb_may_pull(skb, sizeof(*trans_hdr))) {
2038 kfree_skb(skb);
2039 return NET_RX_SUCCESS;
2040 }
2041
2042 trans_hdr = iucv_trans_hdr(skb);
2043 EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2044 EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2045 EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2046 EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2047 memset(nullstring, 0, sizeof(nullstring));
2048 iucv = NULL;
2049 sk = NULL;
2050 read_lock(&iucv_sk_list.lock);
2051 sk_for_each(sk, &iucv_sk_list.head) {
2052 if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2053 if ((!memcmp(&iucv_sk(sk)->src_name,
2054 trans_hdr->destAppName, 8)) &&
2055 (!memcmp(&iucv_sk(sk)->src_user_id,
2056 trans_hdr->destUserID, 8)) &&
2057 (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2058 (!memcmp(&iucv_sk(sk)->dst_user_id,
2059 nullstring, 8))) {
2060 iucv = iucv_sk(sk);
2061 break;
2062 }
2063 } else {
2064 if ((!memcmp(&iucv_sk(sk)->src_name,
2065 trans_hdr->destAppName, 8)) &&
2066 (!memcmp(&iucv_sk(sk)->src_user_id,
2067 trans_hdr->destUserID, 8)) &&
2068 (!memcmp(&iucv_sk(sk)->dst_name,
2069 trans_hdr->srcAppName, 8)) &&
2070 (!memcmp(&iucv_sk(sk)->dst_user_id,
2071 trans_hdr->srcUserID, 8))) {
2072 iucv = iucv_sk(sk);
2073 break;
2074 }
2075 }
2076 }
2077 read_unlock(&iucv_sk_list.lock);
2078 if (!iucv)
2079 sk = NULL;
2080
2081 /* no sock
2082 how should we send with no sock
2083 1) send without sock no send rc checking?
2084 2) introduce default sock to handle this cases
2085
2086 SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2087 data -> send FIN
2088 SYN|ACK, SYN|FIN, FIN -> no action? */
2089
2090 switch (trans_hdr->flags) {
2091 case AF_IUCV_FLAG_SYN:
2092 /* connect request */
2093 err = afiucv_hs_callback_syn(sk, skb);
2094 break;
2095 case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2096 /* connect request confirmed */
2097 err = afiucv_hs_callback_synack(sk, skb);
2098 break;
2099 case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2100 /* connect request refused */
2101 err = afiucv_hs_callback_synfin(sk, skb);
2102 break;
2103 case (AF_IUCV_FLAG_FIN):
2104 /* close request */
2105 err = afiucv_hs_callback_fin(sk, skb);
2106 break;
2107 case (AF_IUCV_FLAG_WIN):
2108 err = afiucv_hs_callback_win(sk, skb);
2109 if (skb->len == sizeof(struct af_iucv_trans_hdr)) {
2110 consume_skb(skb);
2111 break;
2112 }
2113 fallthrough; /* and receive non-zero length data */
2114 case (AF_IUCV_FLAG_SHT):
2115 /* shutdown request */
2116 fallthrough; /* and receive zero length data */
2117 case 0:
2118 /* plain data frame */
2119 IUCV_SKB_CB(skb)->class = trans_hdr->iucv_hdr.class;
2120 err = afiucv_hs_callback_rx(sk, skb);
2121 break;
2122 default:
2123 kfree_skb(skb);
2124 }
2125
2126 return err;
2127 }
2128
2129 /*
2130 * afiucv_hs_callback_txnotify() - handle send notifications from HiperSockets
2131 * transport
2132 */
afiucv_hs_callback_txnotify(struct sock * sk,enum iucv_tx_notify n)2133 static void afiucv_hs_callback_txnotify(struct sock *sk, enum iucv_tx_notify n)
2134 {
2135 struct iucv_sock *iucv = iucv_sk(sk);
2136
2137 if (sock_flag(sk, SOCK_ZAPPED))
2138 return;
2139
2140 switch (n) {
2141 case TX_NOTIFY_OK:
2142 atomic_dec(&iucv->skbs_in_xmit);
2143 iucv_sock_wake_msglim(sk);
2144 break;
2145 case TX_NOTIFY_PENDING:
2146 atomic_inc(&iucv->pendings);
2147 break;
2148 case TX_NOTIFY_DELAYED_OK:
2149 atomic_dec(&iucv->skbs_in_xmit);
2150 if (atomic_dec_return(&iucv->pendings) <= 0)
2151 iucv_sock_wake_msglim(sk);
2152 break;
2153 default:
2154 atomic_dec(&iucv->skbs_in_xmit);
2155 if (sk->sk_state == IUCV_CONNECTED) {
2156 sk->sk_state = IUCV_DISCONN;
2157 sk->sk_state_change(sk);
2158 }
2159 }
2160
2161 if (sk->sk_state == IUCV_CLOSING) {
2162 if (atomic_read(&iucv->skbs_in_xmit) == 0) {
2163 sk->sk_state = IUCV_CLOSED;
2164 sk->sk_state_change(sk);
2165 }
2166 }
2167 }
2168
2169 /*
2170 * afiucv_netdev_event: handle netdev notifier chain events
2171 */
afiucv_netdev_event(struct notifier_block * this,unsigned long event,void * ptr)2172 static int afiucv_netdev_event(struct notifier_block *this,
2173 unsigned long event, void *ptr)
2174 {
2175 struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2176 struct sock *sk;
2177 struct iucv_sock *iucv;
2178
2179 switch (event) {
2180 case NETDEV_REBOOT:
2181 case NETDEV_GOING_DOWN:
2182 sk_for_each(sk, &iucv_sk_list.head) {
2183 iucv = iucv_sk(sk);
2184 if ((iucv->hs_dev == event_dev) &&
2185 (sk->sk_state == IUCV_CONNECTED)) {
2186 if (event == NETDEV_GOING_DOWN)
2187 iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
2188 sk->sk_state = IUCV_DISCONN;
2189 sk->sk_state_change(sk);
2190 }
2191 }
2192 break;
2193 case NETDEV_DOWN:
2194 case NETDEV_UNREGISTER:
2195 default:
2196 break;
2197 }
2198 return NOTIFY_DONE;
2199 }
2200
2201 static struct notifier_block afiucv_netdev_notifier = {
2202 .notifier_call = afiucv_netdev_event,
2203 };
2204
2205 static const struct proto_ops iucv_sock_ops = {
2206 .family = PF_IUCV,
2207 .owner = THIS_MODULE,
2208 .release = iucv_sock_release,
2209 .bind = iucv_sock_bind,
2210 .connect = iucv_sock_connect,
2211 .listen = iucv_sock_listen,
2212 .accept = iucv_sock_accept,
2213 .getname = iucv_sock_getname,
2214 .sendmsg = iucv_sock_sendmsg,
2215 .recvmsg = iucv_sock_recvmsg,
2216 .poll = iucv_sock_poll,
2217 .ioctl = sock_no_ioctl,
2218 .mmap = sock_no_mmap,
2219 .socketpair = sock_no_socketpair,
2220 .shutdown = iucv_sock_shutdown,
2221 .setsockopt = iucv_sock_setsockopt,
2222 .getsockopt = iucv_sock_getsockopt,
2223 };
2224
iucv_sock_create(struct net * net,struct socket * sock,int protocol,int kern)2225 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
2226 int kern)
2227 {
2228 struct sock *sk;
2229
2230 if (protocol && protocol != PF_IUCV)
2231 return -EPROTONOSUPPORT;
2232
2233 sock->state = SS_UNCONNECTED;
2234
2235 switch (sock->type) {
2236 case SOCK_STREAM:
2237 case SOCK_SEQPACKET:
2238 /* currently, proto ops can handle both sk types */
2239 sock->ops = &iucv_sock_ops;
2240 break;
2241 default:
2242 return -ESOCKTNOSUPPORT;
2243 }
2244
2245 sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL, kern);
2246 if (!sk)
2247 return -ENOMEM;
2248
2249 iucv_sock_init(sk, NULL);
2250
2251 return 0;
2252 }
2253
2254 static const struct net_proto_family iucv_sock_family_ops = {
2255 .family = AF_IUCV,
2256 .owner = THIS_MODULE,
2257 .create = iucv_sock_create,
2258 };
2259
2260 static struct packet_type iucv_packet_type = {
2261 .type = cpu_to_be16(ETH_P_AF_IUCV),
2262 .func = afiucv_hs_rcv,
2263 };
2264
afiucv_init(void)2265 static int __init afiucv_init(void)
2266 {
2267 int err;
2268
2269 if (MACHINE_IS_VM && IS_ENABLED(CONFIG_IUCV)) {
2270 cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2271 if (unlikely(err)) {
2272 WARN_ON(err);
2273 err = -EPROTONOSUPPORT;
2274 goto out;
2275 }
2276
2277 pr_iucv = &iucv_if;
2278 } else {
2279 memset(&iucv_userid, 0, sizeof(iucv_userid));
2280 pr_iucv = NULL;
2281 }
2282
2283 err = proto_register(&iucv_proto, 0);
2284 if (err)
2285 goto out;
2286 err = sock_register(&iucv_sock_family_ops);
2287 if (err)
2288 goto out_proto;
2289
2290 if (pr_iucv) {
2291 err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2292 if (err)
2293 goto out_sock;
2294 }
2295
2296 err = register_netdevice_notifier(&afiucv_netdev_notifier);
2297 if (err)
2298 goto out_notifier;
2299
2300 dev_add_pack(&iucv_packet_type);
2301 return 0;
2302
2303 out_notifier:
2304 if (pr_iucv)
2305 pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2306 out_sock:
2307 sock_unregister(PF_IUCV);
2308 out_proto:
2309 proto_unregister(&iucv_proto);
2310 out:
2311 return err;
2312 }
2313
afiucv_exit(void)2314 static void __exit afiucv_exit(void)
2315 {
2316 if (pr_iucv)
2317 pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2318
2319 unregister_netdevice_notifier(&afiucv_netdev_notifier);
2320 dev_remove_pack(&iucv_packet_type);
2321 sock_unregister(PF_IUCV);
2322 proto_unregister(&iucv_proto);
2323 }
2324
2325 module_init(afiucv_init);
2326 module_exit(afiucv_exit);
2327
2328 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2329 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2330 MODULE_VERSION(VERSION);
2331 MODULE_LICENSE("GPL");
2332 MODULE_ALIAS_NETPROTO(PF_IUCV);
2333