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_rcu(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 if (iucv->path) {
339 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,struct proto_accept_arg * arg)797 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
798 struct proto_accept_arg *arg)
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, arg->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 = virt_to_dma32(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 = virt_to_dma32(skb_frag_address(frag));
1069 iba[i + 1].length = (u32)skb_frag_size(frag);
1070 }
1071 err = pr_iucv->message_send(iucv->path, &txmsg,
1072 IUCV_IPBUFLST, 0,
1073 (void *)iba, skb->len);
1074 } else { /* non-IPRM Linear skb */
1075 err = pr_iucv->message_send(iucv->path, &txmsg,
1076 0, 0, (void *)skb->data, skb->len);
1077 }
1078 if (err) {
1079 if (err == 3) {
1080 user_id[8] = 0;
1081 memcpy(user_id, iucv->dst_user_id, 8);
1082 appl_id[8] = 0;
1083 memcpy(appl_id, iucv->dst_name, 8);
1084 pr_err(
1085 "Application %s on z/VM guest %s exceeds message limit\n",
1086 appl_id, user_id);
1087 err = -EAGAIN;
1088 } else {
1089 err = -EPIPE;
1090 }
1091
1092 atomic_dec(&iucv->skbs_in_xmit);
1093 skb_unlink(skb, &iucv->send_skb_q);
1094 goto fail;
1095 }
1096 }
1097
1098 release_sock(sk);
1099 return len;
1100
1101 fail:
1102 kfree_skb(skb);
1103 out:
1104 release_sock(sk);
1105 return err;
1106 }
1107
alloc_iucv_recv_skb(unsigned long len)1108 static struct sk_buff *alloc_iucv_recv_skb(unsigned long len)
1109 {
1110 size_t headroom, linear;
1111 struct sk_buff *skb;
1112 int err;
1113
1114 if (len < PAGE_SIZE) {
1115 headroom = 0;
1116 linear = len;
1117 } else {
1118 headroom = sizeof(struct iucv_array) * (MAX_SKB_FRAGS + 1);
1119 linear = PAGE_SIZE - headroom;
1120 }
1121 skb = alloc_skb_with_frags(headroom + linear, len - linear,
1122 0, &err, GFP_ATOMIC | GFP_DMA);
1123 WARN_ONCE(!skb,
1124 "alloc of recv iucv skb len=%lu failed with errcode=%d\n",
1125 len, err);
1126 if (skb) {
1127 if (headroom)
1128 skb_reserve(skb, headroom);
1129 skb_put(skb, linear);
1130 skb->len = len;
1131 skb->data_len = len - linear;
1132 }
1133 return skb;
1134 }
1135
1136 /* iucv_process_message() - Receive a single outstanding IUCV message
1137 *
1138 * Locking: must be called with message_q.lock held
1139 */
iucv_process_message(struct sock * sk,struct sk_buff * skb,struct iucv_path * path,struct iucv_message * msg)1140 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1141 struct iucv_path *path,
1142 struct iucv_message *msg)
1143 {
1144 int rc;
1145 unsigned int len;
1146
1147 len = iucv_msg_length(msg);
1148
1149 /* store msg target class in the second 4 bytes of skb ctrl buffer */
1150 /* Note: the first 4 bytes are reserved for msg tag */
1151 IUCV_SKB_CB(skb)->class = msg->class;
1152
1153 /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1154 if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1155 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1156 skb->data = NULL;
1157 skb->len = 0;
1158 }
1159 } else {
1160 if (skb_is_nonlinear(skb)) {
1161 struct iucv_array *iba = (struct iucv_array *)skb->head;
1162 int i;
1163
1164 iba[0].address = virt_to_dma32(skb->data);
1165 iba[0].length = (u32)skb_headlen(skb);
1166 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1167 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1168
1169 iba[i + 1].address = virt_to_dma32(skb_frag_address(frag));
1170 iba[i + 1].length = (u32)skb_frag_size(frag);
1171 }
1172 rc = pr_iucv->message_receive(path, msg,
1173 IUCV_IPBUFLST,
1174 (void *)iba, len, NULL);
1175 } else {
1176 rc = pr_iucv->message_receive(path, msg,
1177 msg->flags & IUCV_IPRMDATA,
1178 skb->data, len, NULL);
1179 }
1180 if (rc) {
1181 kfree_skb(skb);
1182 return;
1183 }
1184 WARN_ON_ONCE(skb->len != len);
1185 }
1186
1187 IUCV_SKB_CB(skb)->offset = 0;
1188 if (sk_filter(sk, skb)) {
1189 atomic_inc(&sk->sk_drops); /* skb rejected by filter */
1190 kfree_skb(skb);
1191 return;
1192 }
1193 if (__sock_queue_rcv_skb(sk, skb)) /* handle rcv queue full */
1194 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
1195 }
1196
1197 /* iucv_process_message_q() - Process outstanding IUCV messages
1198 *
1199 * Locking: must be called with message_q.lock held
1200 */
iucv_process_message_q(struct sock * sk)1201 static void iucv_process_message_q(struct sock *sk)
1202 {
1203 struct iucv_sock *iucv = iucv_sk(sk);
1204 struct sk_buff *skb;
1205 struct sock_msg_q *p, *n;
1206
1207 list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1208 skb = alloc_iucv_recv_skb(iucv_msg_length(&p->msg));
1209 if (!skb)
1210 break;
1211 iucv_process_message(sk, skb, p->path, &p->msg);
1212 list_del(&p->list);
1213 kfree(p);
1214 if (!skb_queue_empty(&iucv->backlog_skb_q))
1215 break;
1216 }
1217 }
1218
iucv_sock_recvmsg(struct socket * sock,struct msghdr * msg,size_t len,int flags)1219 static int iucv_sock_recvmsg(struct socket *sock, struct msghdr *msg,
1220 size_t len, int flags)
1221 {
1222 struct sock *sk = sock->sk;
1223 struct iucv_sock *iucv = iucv_sk(sk);
1224 unsigned int copied, rlen;
1225 struct sk_buff *skb, *rskb, *cskb;
1226 int err = 0;
1227 u32 offset;
1228
1229 if ((sk->sk_state == IUCV_DISCONN) &&
1230 skb_queue_empty(&iucv->backlog_skb_q) &&
1231 skb_queue_empty(&sk->sk_receive_queue) &&
1232 list_empty(&iucv->message_q.list))
1233 return 0;
1234
1235 if (flags & (MSG_OOB))
1236 return -EOPNOTSUPP;
1237
1238 /* receive/dequeue next skb:
1239 * the function understands MSG_PEEK and, thus, does not dequeue skb */
1240 skb = skb_recv_datagram(sk, flags, &err);
1241 if (!skb) {
1242 if (sk->sk_shutdown & RCV_SHUTDOWN)
1243 return 0;
1244 return err;
1245 }
1246
1247 offset = IUCV_SKB_CB(skb)->offset;
1248 rlen = skb->len - offset; /* real length of skb */
1249 copied = min_t(unsigned int, rlen, len);
1250 if (!rlen)
1251 sk->sk_shutdown = sk->sk_shutdown | RCV_SHUTDOWN;
1252
1253 cskb = skb;
1254 if (skb_copy_datagram_msg(cskb, offset, msg, copied)) {
1255 if (!(flags & MSG_PEEK))
1256 skb_queue_head(&sk->sk_receive_queue, skb);
1257 return -EFAULT;
1258 }
1259
1260 /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1261 if (sk->sk_type == SOCK_SEQPACKET) {
1262 if (copied < rlen)
1263 msg->msg_flags |= MSG_TRUNC;
1264 /* each iucv message contains a complete record */
1265 msg->msg_flags |= MSG_EOR;
1266 }
1267
1268 /* create control message to store iucv msg target class:
1269 * get the trgcls from the control buffer of the skb due to
1270 * fragmentation of original iucv message. */
1271 err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1272 sizeof(IUCV_SKB_CB(skb)->class),
1273 (void *)&IUCV_SKB_CB(skb)->class);
1274 if (err) {
1275 if (!(flags & MSG_PEEK))
1276 skb_queue_head(&sk->sk_receive_queue, skb);
1277 return err;
1278 }
1279
1280 /* Mark read part of skb as used */
1281 if (!(flags & MSG_PEEK)) {
1282
1283 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1284 if (sk->sk_type == SOCK_STREAM) {
1285 if (copied < rlen) {
1286 IUCV_SKB_CB(skb)->offset = offset + copied;
1287 skb_queue_head(&sk->sk_receive_queue, skb);
1288 goto done;
1289 }
1290 }
1291
1292 consume_skb(skb);
1293 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1294 atomic_inc(&iucv->msg_recv);
1295 if (atomic_read(&iucv->msg_recv) > iucv->msglimit) {
1296 WARN_ON(1);
1297 iucv_sock_close(sk);
1298 return -EFAULT;
1299 }
1300 }
1301
1302 /* Queue backlog skbs */
1303 spin_lock_bh(&iucv->message_q.lock);
1304 rskb = skb_dequeue(&iucv->backlog_skb_q);
1305 while (rskb) {
1306 IUCV_SKB_CB(rskb)->offset = 0;
1307 if (__sock_queue_rcv_skb(sk, rskb)) {
1308 /* handle rcv queue full */
1309 skb_queue_head(&iucv->backlog_skb_q,
1310 rskb);
1311 break;
1312 }
1313 rskb = skb_dequeue(&iucv->backlog_skb_q);
1314 }
1315 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1316 if (!list_empty(&iucv->message_q.list))
1317 iucv_process_message_q(sk);
1318 if (atomic_read(&iucv->msg_recv) >=
1319 iucv->msglimit / 2) {
1320 err = iucv_send_ctrl(sk, AF_IUCV_FLAG_WIN);
1321 if (err) {
1322 sk->sk_state = IUCV_DISCONN;
1323 sk->sk_state_change(sk);
1324 }
1325 }
1326 }
1327 spin_unlock_bh(&iucv->message_q.lock);
1328 }
1329
1330 done:
1331 /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1332 if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1333 copied = rlen;
1334
1335 return copied;
1336 }
1337
iucv_accept_poll(struct sock * parent)1338 static inline __poll_t iucv_accept_poll(struct sock *parent)
1339 {
1340 struct iucv_sock *isk, *n;
1341 struct sock *sk;
1342
1343 list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1344 sk = (struct sock *) isk;
1345
1346 if (sk->sk_state == IUCV_CONNECTED)
1347 return EPOLLIN | EPOLLRDNORM;
1348 }
1349
1350 return 0;
1351 }
1352
iucv_sock_poll(struct file * file,struct socket * sock,poll_table * wait)1353 static __poll_t iucv_sock_poll(struct file *file, struct socket *sock,
1354 poll_table *wait)
1355 {
1356 struct sock *sk = sock->sk;
1357 __poll_t mask = 0;
1358
1359 sock_poll_wait(file, sock, wait);
1360
1361 if (sk->sk_state == IUCV_LISTEN)
1362 return iucv_accept_poll(sk);
1363
1364 if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1365 mask |= EPOLLERR |
1366 (sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
1367
1368 if (sk->sk_shutdown & RCV_SHUTDOWN)
1369 mask |= EPOLLRDHUP;
1370
1371 if (sk->sk_shutdown == SHUTDOWN_MASK)
1372 mask |= EPOLLHUP;
1373
1374 if (!skb_queue_empty(&sk->sk_receive_queue) ||
1375 (sk->sk_shutdown & RCV_SHUTDOWN))
1376 mask |= EPOLLIN | EPOLLRDNORM;
1377
1378 if (sk->sk_state == IUCV_CLOSED)
1379 mask |= EPOLLHUP;
1380
1381 if (sk->sk_state == IUCV_DISCONN)
1382 mask |= EPOLLIN;
1383
1384 if (sock_writeable(sk) && iucv_below_msglim(sk))
1385 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
1386 else
1387 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1388
1389 return mask;
1390 }
1391
iucv_sock_shutdown(struct socket * sock,int how)1392 static int iucv_sock_shutdown(struct socket *sock, int how)
1393 {
1394 struct sock *sk = sock->sk;
1395 struct iucv_sock *iucv = iucv_sk(sk);
1396 struct iucv_message txmsg;
1397 int err = 0;
1398
1399 how++;
1400
1401 if ((how & ~SHUTDOWN_MASK) || !how)
1402 return -EINVAL;
1403
1404 lock_sock(sk);
1405 switch (sk->sk_state) {
1406 case IUCV_LISTEN:
1407 case IUCV_DISCONN:
1408 case IUCV_CLOSING:
1409 case IUCV_CLOSED:
1410 err = -ENOTCONN;
1411 goto fail;
1412 default:
1413 break;
1414 }
1415
1416 if ((how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) &&
1417 sk->sk_state == IUCV_CONNECTED) {
1418 if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1419 txmsg.class = 0;
1420 txmsg.tag = 0;
1421 err = pr_iucv->message_send(iucv->path, &txmsg,
1422 IUCV_IPRMDATA, 0, (void *) iprm_shutdown, 8);
1423 if (err) {
1424 switch (err) {
1425 case 1:
1426 err = -ENOTCONN;
1427 break;
1428 case 2:
1429 err = -ECONNRESET;
1430 break;
1431 default:
1432 err = -ENOTCONN;
1433 break;
1434 }
1435 }
1436 } else
1437 iucv_send_ctrl(sk, AF_IUCV_FLAG_SHT);
1438 }
1439
1440 sk->sk_shutdown |= how;
1441 if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1442 if ((iucv->transport == AF_IUCV_TRANS_IUCV) &&
1443 iucv->path) {
1444 err = pr_iucv->path_quiesce(iucv->path, NULL);
1445 if (err)
1446 err = -ENOTCONN;
1447 /* skb_queue_purge(&sk->sk_receive_queue); */
1448 }
1449 skb_queue_purge(&sk->sk_receive_queue);
1450 }
1451
1452 /* Wake up anyone sleeping in poll */
1453 sk->sk_state_change(sk);
1454
1455 fail:
1456 release_sock(sk);
1457 return err;
1458 }
1459
iucv_sock_release(struct socket * sock)1460 static int iucv_sock_release(struct socket *sock)
1461 {
1462 struct sock *sk = sock->sk;
1463 int err = 0;
1464
1465 if (!sk)
1466 return 0;
1467
1468 iucv_sock_close(sk);
1469
1470 sock_orphan(sk);
1471 iucv_sock_kill(sk);
1472 return err;
1473 }
1474
1475 /* getsockopt and setsockopt */
iucv_sock_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)1476 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1477 sockptr_t optval, unsigned int optlen)
1478 {
1479 struct sock *sk = sock->sk;
1480 struct iucv_sock *iucv = iucv_sk(sk);
1481 int val;
1482 int rc;
1483
1484 if (level != SOL_IUCV)
1485 return -ENOPROTOOPT;
1486
1487 if (optlen < sizeof(int))
1488 return -EINVAL;
1489
1490 if (copy_from_sockptr(&val, optval, sizeof(int)))
1491 return -EFAULT;
1492
1493 rc = 0;
1494
1495 lock_sock(sk);
1496 switch (optname) {
1497 case SO_IPRMDATA_MSG:
1498 if (val)
1499 iucv->flags |= IUCV_IPRMDATA;
1500 else
1501 iucv->flags &= ~IUCV_IPRMDATA;
1502 break;
1503 case SO_MSGLIMIT:
1504 switch (sk->sk_state) {
1505 case IUCV_OPEN:
1506 case IUCV_BOUND:
1507 if (val < 1 || val > U16_MAX)
1508 rc = -EINVAL;
1509 else
1510 iucv->msglimit = val;
1511 break;
1512 default:
1513 rc = -EINVAL;
1514 break;
1515 }
1516 break;
1517 default:
1518 rc = -ENOPROTOOPT;
1519 break;
1520 }
1521 release_sock(sk);
1522
1523 return rc;
1524 }
1525
iucv_sock_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)1526 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1527 char __user *optval, int __user *optlen)
1528 {
1529 struct sock *sk = sock->sk;
1530 struct iucv_sock *iucv = iucv_sk(sk);
1531 unsigned int val;
1532 int len;
1533
1534 if (level != SOL_IUCV)
1535 return -ENOPROTOOPT;
1536
1537 if (get_user(len, optlen))
1538 return -EFAULT;
1539
1540 if (len < 0)
1541 return -EINVAL;
1542
1543 len = min_t(unsigned int, len, sizeof(int));
1544
1545 switch (optname) {
1546 case SO_IPRMDATA_MSG:
1547 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1548 break;
1549 case SO_MSGLIMIT:
1550 lock_sock(sk);
1551 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1552 : iucv->msglimit; /* default */
1553 release_sock(sk);
1554 break;
1555 case SO_MSGSIZE:
1556 if (sk->sk_state == IUCV_OPEN)
1557 return -EBADFD;
1558 val = (iucv->hs_dev) ? iucv->hs_dev->mtu -
1559 sizeof(struct af_iucv_trans_hdr) - ETH_HLEN :
1560 0x7fffffff;
1561 break;
1562 default:
1563 return -ENOPROTOOPT;
1564 }
1565
1566 if (put_user(len, optlen))
1567 return -EFAULT;
1568 if (copy_to_user(optval, &val, len))
1569 return -EFAULT;
1570
1571 return 0;
1572 }
1573
1574
1575 /* Callback wrappers - called from iucv base support */
iucv_callback_connreq(struct iucv_path * path,u8 ipvmid[8],u8 ipuser[16])1576 static int iucv_callback_connreq(struct iucv_path *path,
1577 u8 ipvmid[8], u8 ipuser[16])
1578 {
1579 unsigned char user_data[16];
1580 unsigned char nuser_data[16];
1581 unsigned char src_name[8];
1582 struct sock *sk, *nsk;
1583 struct iucv_sock *iucv, *niucv;
1584 int err;
1585
1586 memcpy(src_name, ipuser, 8);
1587 EBCASC(src_name, 8);
1588 /* Find out if this path belongs to af_iucv. */
1589 read_lock(&iucv_sk_list.lock);
1590 iucv = NULL;
1591 sk = NULL;
1592 sk_for_each(sk, &iucv_sk_list.head)
1593 if (sk->sk_state == IUCV_LISTEN &&
1594 !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1595 /*
1596 * Found a listening socket with
1597 * src_name == ipuser[0-7].
1598 */
1599 iucv = iucv_sk(sk);
1600 break;
1601 }
1602 read_unlock(&iucv_sk_list.lock);
1603 if (!iucv)
1604 /* No socket found, not one of our paths. */
1605 return -EINVAL;
1606
1607 bh_lock_sock(sk);
1608
1609 /* Check if parent socket is listening */
1610 low_nmcpy(user_data, iucv->src_name);
1611 high_nmcpy(user_data, iucv->dst_name);
1612 ASCEBC(user_data, sizeof(user_data));
1613 if (sk->sk_state != IUCV_LISTEN) {
1614 err = pr_iucv->path_sever(path, user_data);
1615 iucv_path_free(path);
1616 goto fail;
1617 }
1618
1619 /* Check for backlog size */
1620 if (sk_acceptq_is_full(sk)) {
1621 err = pr_iucv->path_sever(path, user_data);
1622 iucv_path_free(path);
1623 goto fail;
1624 }
1625
1626 /* Create the new socket */
1627 nsk = iucv_sock_alloc(NULL, sk->sk_protocol, GFP_ATOMIC, 0);
1628 if (!nsk) {
1629 err = pr_iucv->path_sever(path, user_data);
1630 iucv_path_free(path);
1631 goto fail;
1632 }
1633
1634 niucv = iucv_sk(nsk);
1635 iucv_sock_init(nsk, sk);
1636 niucv->transport = AF_IUCV_TRANS_IUCV;
1637 nsk->sk_allocation |= GFP_DMA;
1638
1639 /* Set the new iucv_sock */
1640 memcpy(niucv->dst_name, ipuser + 8, 8);
1641 EBCASC(niucv->dst_name, 8);
1642 memcpy(niucv->dst_user_id, ipvmid, 8);
1643 memcpy(niucv->src_name, iucv->src_name, 8);
1644 memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1645 niucv->path = path;
1646
1647 /* Call iucv_accept */
1648 high_nmcpy(nuser_data, ipuser + 8);
1649 memcpy(nuser_data + 8, niucv->src_name, 8);
1650 ASCEBC(nuser_data + 8, 8);
1651
1652 /* set message limit for path based on msglimit of accepting socket */
1653 niucv->msglimit = iucv->msglimit;
1654 path->msglim = iucv->msglimit;
1655 err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1656 if (err) {
1657 iucv_sever_path(nsk, 1);
1658 iucv_sock_kill(nsk);
1659 goto fail;
1660 }
1661
1662 iucv_accept_enqueue(sk, nsk);
1663
1664 /* Wake up accept */
1665 nsk->sk_state = IUCV_CONNECTED;
1666 sk->sk_data_ready(sk);
1667 err = 0;
1668 fail:
1669 bh_unlock_sock(sk);
1670 return 0;
1671 }
1672
iucv_callback_connack(struct iucv_path * path,u8 ipuser[16])1673 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1674 {
1675 struct sock *sk = path->private;
1676
1677 sk->sk_state = IUCV_CONNECTED;
1678 sk->sk_state_change(sk);
1679 }
1680
iucv_callback_rx(struct iucv_path * path,struct iucv_message * msg)1681 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1682 {
1683 struct sock *sk = path->private;
1684 struct iucv_sock *iucv = iucv_sk(sk);
1685 struct sk_buff *skb;
1686 struct sock_msg_q *save_msg;
1687 int len;
1688
1689 if (sk->sk_shutdown & RCV_SHUTDOWN) {
1690 pr_iucv->message_reject(path, msg);
1691 return;
1692 }
1693
1694 spin_lock(&iucv->message_q.lock);
1695
1696 if (!list_empty(&iucv->message_q.list) ||
1697 !skb_queue_empty(&iucv->backlog_skb_q))
1698 goto save_message;
1699
1700 len = atomic_read(&sk->sk_rmem_alloc);
1701 len += SKB_TRUESIZE(iucv_msg_length(msg));
1702 if (len > sk->sk_rcvbuf)
1703 goto save_message;
1704
1705 skb = alloc_iucv_recv_skb(iucv_msg_length(msg));
1706 if (!skb)
1707 goto save_message;
1708
1709 iucv_process_message(sk, skb, path, msg);
1710 goto out_unlock;
1711
1712 save_message:
1713 save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1714 if (!save_msg)
1715 goto out_unlock;
1716 save_msg->path = path;
1717 save_msg->msg = *msg;
1718
1719 list_add_tail(&save_msg->list, &iucv->message_q.list);
1720
1721 out_unlock:
1722 spin_unlock(&iucv->message_q.lock);
1723 }
1724
iucv_callback_txdone(struct iucv_path * path,struct iucv_message * msg)1725 static void iucv_callback_txdone(struct iucv_path *path,
1726 struct iucv_message *msg)
1727 {
1728 struct sock *sk = path->private;
1729 struct sk_buff *this = NULL;
1730 struct sk_buff_head *list;
1731 struct sk_buff *list_skb;
1732 struct iucv_sock *iucv;
1733 unsigned long flags;
1734
1735 iucv = iucv_sk(sk);
1736 list = &iucv->send_skb_q;
1737
1738 bh_lock_sock(sk);
1739
1740 spin_lock_irqsave(&list->lock, flags);
1741 skb_queue_walk(list, list_skb) {
1742 if (msg->tag == IUCV_SKB_CB(list_skb)->tag) {
1743 this = list_skb;
1744 break;
1745 }
1746 }
1747 if (this) {
1748 atomic_dec(&iucv->skbs_in_xmit);
1749 __skb_unlink(this, list);
1750 }
1751
1752 spin_unlock_irqrestore(&list->lock, flags);
1753
1754 if (this) {
1755 consume_skb(this);
1756 /* wake up any process waiting for sending */
1757 iucv_sock_wake_msglim(sk);
1758 }
1759
1760 if (sk->sk_state == IUCV_CLOSING) {
1761 if (atomic_read(&iucv->skbs_in_xmit) == 0) {
1762 sk->sk_state = IUCV_CLOSED;
1763 sk->sk_state_change(sk);
1764 }
1765 }
1766 bh_unlock_sock(sk);
1767
1768 }
1769
iucv_callback_connrej(struct iucv_path * path,u8 ipuser[16])1770 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1771 {
1772 struct sock *sk = path->private;
1773
1774 if (sk->sk_state == IUCV_CLOSED)
1775 return;
1776
1777 bh_lock_sock(sk);
1778 iucv_sever_path(sk, 1);
1779 sk->sk_state = IUCV_DISCONN;
1780
1781 sk->sk_state_change(sk);
1782 bh_unlock_sock(sk);
1783 }
1784
1785 /* called if the other communication side shuts down its RECV direction;
1786 * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1787 */
iucv_callback_shutdown(struct iucv_path * path,u8 ipuser[16])1788 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1789 {
1790 struct sock *sk = path->private;
1791
1792 bh_lock_sock(sk);
1793 if (sk->sk_state != IUCV_CLOSED) {
1794 sk->sk_shutdown |= SEND_SHUTDOWN;
1795 sk->sk_state_change(sk);
1796 }
1797 bh_unlock_sock(sk);
1798 }
1799
1800 static struct iucv_handler af_iucv_handler = {
1801 .path_pending = iucv_callback_connreq,
1802 .path_complete = iucv_callback_connack,
1803 .path_severed = iucv_callback_connrej,
1804 .message_pending = iucv_callback_rx,
1805 .message_complete = iucv_callback_txdone,
1806 .path_quiesced = iucv_callback_shutdown,
1807 };
1808
1809 /***************** HiperSockets transport callbacks ********************/
afiucv_swap_src_dest(struct sk_buff * skb)1810 static void afiucv_swap_src_dest(struct sk_buff *skb)
1811 {
1812 struct af_iucv_trans_hdr *trans_hdr = iucv_trans_hdr(skb);
1813 char tmpID[8];
1814 char tmpName[8];
1815
1816 ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1817 ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1818 ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1819 ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1820 memcpy(tmpID, trans_hdr->srcUserID, 8);
1821 memcpy(tmpName, trans_hdr->srcAppName, 8);
1822 memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1823 memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1824 memcpy(trans_hdr->destUserID, tmpID, 8);
1825 memcpy(trans_hdr->destAppName, tmpName, 8);
1826 skb_push(skb, ETH_HLEN);
1827 memset(skb->data, 0, ETH_HLEN);
1828 }
1829
1830 /*
1831 * afiucv_hs_callback_syn - react on received SYN
1832 */
afiucv_hs_callback_syn(struct sock * sk,struct sk_buff * skb)1833 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1834 {
1835 struct af_iucv_trans_hdr *trans_hdr = iucv_trans_hdr(skb);
1836 struct sock *nsk;
1837 struct iucv_sock *iucv, *niucv;
1838 int err;
1839
1840 iucv = iucv_sk(sk);
1841 if (!iucv) {
1842 /* no sock - connection refused */
1843 afiucv_swap_src_dest(skb);
1844 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1845 err = dev_queue_xmit(skb);
1846 goto out;
1847 }
1848
1849 nsk = iucv_sock_alloc(NULL, sk->sk_protocol, GFP_ATOMIC, 0);
1850 bh_lock_sock(sk);
1851 if ((sk->sk_state != IUCV_LISTEN) ||
1852 sk_acceptq_is_full(sk) ||
1853 !nsk) {
1854 /* error on server socket - connection refused */
1855 afiucv_swap_src_dest(skb);
1856 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1857 err = dev_queue_xmit(skb);
1858 iucv_sock_kill(nsk);
1859 bh_unlock_sock(sk);
1860 goto out;
1861 }
1862
1863 niucv = iucv_sk(nsk);
1864 iucv_sock_init(nsk, sk);
1865 niucv->transport = AF_IUCV_TRANS_HIPER;
1866 niucv->msglimit = iucv->msglimit;
1867 if (!trans_hdr->window)
1868 niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
1869 else
1870 niucv->msglimit_peer = trans_hdr->window;
1871 memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
1872 memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
1873 memcpy(niucv->src_name, iucv->src_name, 8);
1874 memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1875 nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
1876 niucv->hs_dev = iucv->hs_dev;
1877 dev_hold(niucv->hs_dev);
1878 afiucv_swap_src_dest(skb);
1879 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
1880 trans_hdr->window = niucv->msglimit;
1881 /* if receiver acks the xmit connection is established */
1882 err = dev_queue_xmit(skb);
1883 if (!err) {
1884 iucv_accept_enqueue(sk, nsk);
1885 nsk->sk_state = IUCV_CONNECTED;
1886 sk->sk_data_ready(sk);
1887 } else
1888 iucv_sock_kill(nsk);
1889 bh_unlock_sock(sk);
1890
1891 out:
1892 return NET_RX_SUCCESS;
1893 }
1894
1895 /*
1896 * afiucv_hs_callback_synack() - react on received SYN-ACK
1897 */
afiucv_hs_callback_synack(struct sock * sk,struct sk_buff * skb)1898 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
1899 {
1900 struct iucv_sock *iucv = iucv_sk(sk);
1901
1902 if (!iucv || sk->sk_state != IUCV_BOUND) {
1903 kfree_skb(skb);
1904 return NET_RX_SUCCESS;
1905 }
1906
1907 bh_lock_sock(sk);
1908 iucv->msglimit_peer = iucv_trans_hdr(skb)->window;
1909 sk->sk_state = IUCV_CONNECTED;
1910 sk->sk_state_change(sk);
1911 bh_unlock_sock(sk);
1912 consume_skb(skb);
1913 return NET_RX_SUCCESS;
1914 }
1915
1916 /*
1917 * afiucv_hs_callback_synfin() - react on received SYN_FIN
1918 */
afiucv_hs_callback_synfin(struct sock * sk,struct sk_buff * skb)1919 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
1920 {
1921 struct iucv_sock *iucv = iucv_sk(sk);
1922
1923 if (!iucv || sk->sk_state != IUCV_BOUND) {
1924 kfree_skb(skb);
1925 return NET_RX_SUCCESS;
1926 }
1927
1928 bh_lock_sock(sk);
1929 sk->sk_state = IUCV_DISCONN;
1930 sk->sk_state_change(sk);
1931 bh_unlock_sock(sk);
1932 consume_skb(skb);
1933 return NET_RX_SUCCESS;
1934 }
1935
1936 /*
1937 * afiucv_hs_callback_fin() - react on received FIN
1938 */
afiucv_hs_callback_fin(struct sock * sk,struct sk_buff * skb)1939 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
1940 {
1941 struct iucv_sock *iucv = iucv_sk(sk);
1942
1943 /* other end of connection closed */
1944 if (!iucv) {
1945 kfree_skb(skb);
1946 return NET_RX_SUCCESS;
1947 }
1948
1949 bh_lock_sock(sk);
1950 if (sk->sk_state == IUCV_CONNECTED) {
1951 sk->sk_state = IUCV_DISCONN;
1952 sk->sk_state_change(sk);
1953 }
1954 bh_unlock_sock(sk);
1955 consume_skb(skb);
1956 return NET_RX_SUCCESS;
1957 }
1958
1959 /*
1960 * afiucv_hs_callback_win() - react on received WIN
1961 */
afiucv_hs_callback_win(struct sock * sk,struct sk_buff * skb)1962 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
1963 {
1964 struct iucv_sock *iucv = iucv_sk(sk);
1965
1966 if (!iucv)
1967 return NET_RX_SUCCESS;
1968
1969 if (sk->sk_state != IUCV_CONNECTED)
1970 return NET_RX_SUCCESS;
1971
1972 atomic_sub(iucv_trans_hdr(skb)->window, &iucv->msg_sent);
1973 iucv_sock_wake_msglim(sk);
1974 return NET_RX_SUCCESS;
1975 }
1976
1977 /*
1978 * afiucv_hs_callback_rx() - react on received data
1979 */
afiucv_hs_callback_rx(struct sock * sk,struct sk_buff * skb)1980 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
1981 {
1982 struct iucv_sock *iucv = iucv_sk(sk);
1983
1984 if (!iucv) {
1985 kfree_skb(skb);
1986 return NET_RX_SUCCESS;
1987 }
1988
1989 if (sk->sk_state != IUCV_CONNECTED) {
1990 kfree_skb(skb);
1991 return NET_RX_SUCCESS;
1992 }
1993
1994 if (sk->sk_shutdown & RCV_SHUTDOWN) {
1995 kfree_skb(skb);
1996 return NET_RX_SUCCESS;
1997 }
1998
1999 /* write stuff from iucv_msg to skb cb */
2000 skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2001 skb_reset_transport_header(skb);
2002 skb_reset_network_header(skb);
2003 IUCV_SKB_CB(skb)->offset = 0;
2004 if (sk_filter(sk, skb)) {
2005 atomic_inc(&sk->sk_drops); /* skb rejected by filter */
2006 kfree_skb(skb);
2007 return NET_RX_SUCCESS;
2008 }
2009
2010 spin_lock(&iucv->message_q.lock);
2011 if (skb_queue_empty(&iucv->backlog_skb_q)) {
2012 if (__sock_queue_rcv_skb(sk, skb))
2013 /* handle rcv queue full */
2014 skb_queue_tail(&iucv->backlog_skb_q, skb);
2015 } else
2016 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2017 spin_unlock(&iucv->message_q.lock);
2018 return NET_RX_SUCCESS;
2019 }
2020
2021 /*
2022 * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2023 * transport
2024 * called from netif RX softirq
2025 */
afiucv_hs_rcv(struct sk_buff * skb,struct net_device * dev,struct packet_type * pt,struct net_device * orig_dev)2026 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2027 struct packet_type *pt, struct net_device *orig_dev)
2028 {
2029 struct sock *sk;
2030 struct iucv_sock *iucv;
2031 struct af_iucv_trans_hdr *trans_hdr;
2032 int err = NET_RX_SUCCESS;
2033 char nullstring[8];
2034
2035 if (!pskb_may_pull(skb, sizeof(*trans_hdr))) {
2036 kfree_skb(skb);
2037 return NET_RX_SUCCESS;
2038 }
2039
2040 trans_hdr = iucv_trans_hdr(skb);
2041 EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2042 EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2043 EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2044 EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2045 memset(nullstring, 0, sizeof(nullstring));
2046 iucv = NULL;
2047 sk = NULL;
2048 read_lock(&iucv_sk_list.lock);
2049 sk_for_each(sk, &iucv_sk_list.head) {
2050 if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2051 if ((!memcmp(&iucv_sk(sk)->src_name,
2052 trans_hdr->destAppName, 8)) &&
2053 (!memcmp(&iucv_sk(sk)->src_user_id,
2054 trans_hdr->destUserID, 8)) &&
2055 (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2056 (!memcmp(&iucv_sk(sk)->dst_user_id,
2057 nullstring, 8))) {
2058 iucv = iucv_sk(sk);
2059 break;
2060 }
2061 } else {
2062 if ((!memcmp(&iucv_sk(sk)->src_name,
2063 trans_hdr->destAppName, 8)) &&
2064 (!memcmp(&iucv_sk(sk)->src_user_id,
2065 trans_hdr->destUserID, 8)) &&
2066 (!memcmp(&iucv_sk(sk)->dst_name,
2067 trans_hdr->srcAppName, 8)) &&
2068 (!memcmp(&iucv_sk(sk)->dst_user_id,
2069 trans_hdr->srcUserID, 8))) {
2070 iucv = iucv_sk(sk);
2071 break;
2072 }
2073 }
2074 }
2075 read_unlock(&iucv_sk_list.lock);
2076 if (!iucv)
2077 sk = NULL;
2078
2079 /* no sock
2080 how should we send with no sock
2081 1) send without sock no send rc checking?
2082 2) introduce default sock to handle this cases
2083
2084 SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2085 data -> send FIN
2086 SYN|ACK, SYN|FIN, FIN -> no action? */
2087
2088 switch (trans_hdr->flags) {
2089 case AF_IUCV_FLAG_SYN:
2090 /* connect request */
2091 err = afiucv_hs_callback_syn(sk, skb);
2092 break;
2093 case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2094 /* connect request confirmed */
2095 err = afiucv_hs_callback_synack(sk, skb);
2096 break;
2097 case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2098 /* connect request refused */
2099 err = afiucv_hs_callback_synfin(sk, skb);
2100 break;
2101 case (AF_IUCV_FLAG_FIN):
2102 /* close request */
2103 err = afiucv_hs_callback_fin(sk, skb);
2104 break;
2105 case (AF_IUCV_FLAG_WIN):
2106 err = afiucv_hs_callback_win(sk, skb);
2107 if (skb->len == sizeof(struct af_iucv_trans_hdr)) {
2108 consume_skb(skb);
2109 break;
2110 }
2111 fallthrough; /* and receive non-zero length data */
2112 case (AF_IUCV_FLAG_SHT):
2113 /* shutdown request */
2114 fallthrough; /* and receive zero length data */
2115 case 0:
2116 /* plain data frame */
2117 IUCV_SKB_CB(skb)->class = trans_hdr->iucv_hdr.class;
2118 err = afiucv_hs_callback_rx(sk, skb);
2119 break;
2120 default:
2121 kfree_skb(skb);
2122 }
2123
2124 return err;
2125 }
2126
2127 /*
2128 * afiucv_hs_callback_txnotify() - handle send notifications from HiperSockets
2129 * transport
2130 */
afiucv_hs_callback_txnotify(struct sock * sk,enum iucv_tx_notify n)2131 static void afiucv_hs_callback_txnotify(struct sock *sk, enum iucv_tx_notify n)
2132 {
2133 struct iucv_sock *iucv = iucv_sk(sk);
2134
2135 if (sock_flag(sk, SOCK_ZAPPED))
2136 return;
2137
2138 switch (n) {
2139 case TX_NOTIFY_OK:
2140 atomic_dec(&iucv->skbs_in_xmit);
2141 iucv_sock_wake_msglim(sk);
2142 break;
2143 case TX_NOTIFY_PENDING:
2144 atomic_inc(&iucv->pendings);
2145 break;
2146 case TX_NOTIFY_DELAYED_OK:
2147 atomic_dec(&iucv->skbs_in_xmit);
2148 if (atomic_dec_return(&iucv->pendings) <= 0)
2149 iucv_sock_wake_msglim(sk);
2150 break;
2151 default:
2152 atomic_dec(&iucv->skbs_in_xmit);
2153 if (sk->sk_state == IUCV_CONNECTED) {
2154 sk->sk_state = IUCV_DISCONN;
2155 sk->sk_state_change(sk);
2156 }
2157 }
2158
2159 if (sk->sk_state == IUCV_CLOSING) {
2160 if (atomic_read(&iucv->skbs_in_xmit) == 0) {
2161 sk->sk_state = IUCV_CLOSED;
2162 sk->sk_state_change(sk);
2163 }
2164 }
2165 }
2166
2167 /*
2168 * afiucv_netdev_event: handle netdev notifier chain events
2169 */
afiucv_netdev_event(struct notifier_block * this,unsigned long event,void * ptr)2170 static int afiucv_netdev_event(struct notifier_block *this,
2171 unsigned long event, void *ptr)
2172 {
2173 struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2174 struct sock *sk;
2175 struct iucv_sock *iucv;
2176
2177 switch (event) {
2178 case NETDEV_REBOOT:
2179 case NETDEV_GOING_DOWN:
2180 sk_for_each(sk, &iucv_sk_list.head) {
2181 iucv = iucv_sk(sk);
2182 if ((iucv->hs_dev == event_dev) &&
2183 (sk->sk_state == IUCV_CONNECTED)) {
2184 if (event == NETDEV_GOING_DOWN)
2185 iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
2186 sk->sk_state = IUCV_DISCONN;
2187 sk->sk_state_change(sk);
2188 }
2189 }
2190 break;
2191 case NETDEV_DOWN:
2192 case NETDEV_UNREGISTER:
2193 default:
2194 break;
2195 }
2196 return NOTIFY_DONE;
2197 }
2198
2199 static struct notifier_block afiucv_netdev_notifier = {
2200 .notifier_call = afiucv_netdev_event,
2201 };
2202
2203 static const struct proto_ops iucv_sock_ops = {
2204 .family = PF_IUCV,
2205 .owner = THIS_MODULE,
2206 .release = iucv_sock_release,
2207 .bind = iucv_sock_bind,
2208 .connect = iucv_sock_connect,
2209 .listen = iucv_sock_listen,
2210 .accept = iucv_sock_accept,
2211 .getname = iucv_sock_getname,
2212 .sendmsg = iucv_sock_sendmsg,
2213 .recvmsg = iucv_sock_recvmsg,
2214 .poll = iucv_sock_poll,
2215 .ioctl = sock_no_ioctl,
2216 .mmap = sock_no_mmap,
2217 .socketpair = sock_no_socketpair,
2218 .shutdown = iucv_sock_shutdown,
2219 .setsockopt = iucv_sock_setsockopt,
2220 .getsockopt = iucv_sock_getsockopt,
2221 };
2222
iucv_sock_create(struct net * net,struct socket * sock,int protocol,int kern)2223 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
2224 int kern)
2225 {
2226 struct sock *sk;
2227
2228 if (protocol && protocol != PF_IUCV)
2229 return -EPROTONOSUPPORT;
2230
2231 sock->state = SS_UNCONNECTED;
2232
2233 switch (sock->type) {
2234 case SOCK_STREAM:
2235 case SOCK_SEQPACKET:
2236 /* currently, proto ops can handle both sk types */
2237 sock->ops = &iucv_sock_ops;
2238 break;
2239 default:
2240 return -ESOCKTNOSUPPORT;
2241 }
2242
2243 sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL, kern);
2244 if (!sk)
2245 return -ENOMEM;
2246
2247 iucv_sock_init(sk, NULL);
2248
2249 return 0;
2250 }
2251
2252 static const struct net_proto_family iucv_sock_family_ops = {
2253 .family = AF_IUCV,
2254 .owner = THIS_MODULE,
2255 .create = iucv_sock_create,
2256 };
2257
2258 static struct packet_type iucv_packet_type = {
2259 .type = cpu_to_be16(ETH_P_AF_IUCV),
2260 .func = afiucv_hs_rcv,
2261 };
2262
afiucv_init(void)2263 static int __init afiucv_init(void)
2264 {
2265 int err;
2266
2267 if (MACHINE_IS_VM && IS_ENABLED(CONFIG_IUCV)) {
2268 cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2269 if (unlikely(err)) {
2270 WARN_ON(err);
2271 err = -EPROTONOSUPPORT;
2272 goto out;
2273 }
2274
2275 pr_iucv = &iucv_if;
2276 } else {
2277 memset(&iucv_userid, 0, sizeof(iucv_userid));
2278 pr_iucv = NULL;
2279 }
2280
2281 err = proto_register(&iucv_proto, 0);
2282 if (err)
2283 goto out;
2284 err = sock_register(&iucv_sock_family_ops);
2285 if (err)
2286 goto out_proto;
2287
2288 if (pr_iucv) {
2289 err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2290 if (err)
2291 goto out_sock;
2292 }
2293
2294 err = register_netdevice_notifier(&afiucv_netdev_notifier);
2295 if (err)
2296 goto out_notifier;
2297
2298 dev_add_pack(&iucv_packet_type);
2299 return 0;
2300
2301 out_notifier:
2302 if (pr_iucv)
2303 pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2304 out_sock:
2305 sock_unregister(PF_IUCV);
2306 out_proto:
2307 proto_unregister(&iucv_proto);
2308 out:
2309 return err;
2310 }
2311
afiucv_exit(void)2312 static void __exit afiucv_exit(void)
2313 {
2314 if (pr_iucv)
2315 pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2316
2317 unregister_netdevice_notifier(&afiucv_netdev_notifier);
2318 dev_remove_pack(&iucv_packet_type);
2319 sock_unregister(PF_IUCV);
2320 proto_unregister(&iucv_proto);
2321 }
2322
2323 module_init(afiucv_init);
2324 module_exit(afiucv_exit);
2325
2326 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2327 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2328 MODULE_VERSION(VERSION);
2329 MODULE_LICENSE("GPL");
2330 MODULE_ALIAS_NETPROTO(PF_IUCV);
2331