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
39static char iucv_userid[80];
40
41static struct proto iucv_proto = {
42	.name		= "AF_IUCV",
43	.owner		= THIS_MODULE,
44	.obj_size	= sizeof(struct iucv_sock),
45};
46
47static struct iucv_interface *pr_iucv;
48static struct iucv_handler af_iucv_handler;
49
50/* special AF_IUCV IPRM messages */
51static 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)			\
57do {									\
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
89static struct sock *iucv_accept_dequeue(struct sock *parent,
90					struct socket *newsock);
91static void iucv_sock_kill(struct sock *sk);
92static void iucv_sock_close(struct sock *sk);
93
94static void afiucv_hs_callback_txnotify(struct sock *sk, enum iucv_tx_notify);
95
96static struct iucv_sock_list iucv_sk_list = {
97	.lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
98	.autobind_name = ATOMIC_INIT(0)
99};
100
101static inline void high_nmcpy(unsigned char *dst, char *src)
102{
103       memcpy(dst, src, 8);
104}
105
106static 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 */
131static 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 */
150static 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 */
163static 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 */
179static 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 */
194static 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
260err_free:
261	kfree_skb(skb);
262	return err;
263}
264
265static 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
276static 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 */
293static 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
306static 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
313static 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) */
321static 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 */
332static 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 */
352static 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 */
378static 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
441static 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
449static 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
493static 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
506static 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
519static 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
551static 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 */
564static 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();
624vm_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;
638done_unlock:
639	/* Release the socket list lock */
640	write_unlock_bh(&iucv_sk_list.lock);
641done:
642	release_sock(sk);
643	return err;
644}
645
646/* Automatically bind an unbound socket */
647static 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
669static 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	}
710done:
711	return err;
712}
713
714/* Connect an unconnected socket */
715static 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
766done:
767	release_sock(sk);
768	return err;
769}
770
771/* Move a socket into listening state. */
772static 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
791done:
792	release_sock(sk);
793	return err;
794}
795
796/* Accept a pending connection */
797static 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
846done:
847	release_sock(sk);
848	return err;
849}
850
851static 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 */
887static 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
898static 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
1101fail:
1102	kfree_skb(skb);
1103out:
1104	release_sock(sk);
1105	return err;
1106}
1107
1108static 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 */
1140static 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 */
1201static 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
1219static 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
1330done:
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
1338static 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
1353static __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
1392static 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
1455fail:
1456	release_sock(sk);
1457	return err;
1458}
1459
1460static 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 */
1476static 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
1526static 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 */
1576static 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;
1668fail:
1669	bh_unlock_sock(sk);
1670	return 0;
1671}
1672
1673static 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
1681static 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
1712save_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
1721out_unlock:
1722	spin_unlock(&iucv->message_q.lock);
1723}
1724
1725static 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
1770static 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 */
1788static 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
1800static 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 ********************/
1810static 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 */
1833static 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
1891out:
1892	return NET_RX_SUCCESS;
1893}
1894
1895/*
1896 * afiucv_hs_callback_synack() - react on received SYN-ACK
1897 */
1898static 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 */
1919static 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 */
1939static 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 */
1962static 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 */
1980static 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 */
2026static 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 */
2131static 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 */
2170static 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
2199static struct notifier_block afiucv_netdev_notifier = {
2200	.notifier_call = afiucv_netdev_event,
2201};
2202
2203static 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
2223static 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
2252static const struct net_proto_family iucv_sock_family_ops = {
2253	.family	= AF_IUCV,
2254	.owner	= THIS_MODULE,
2255	.create	= iucv_sock_create,
2256};
2257
2258static struct packet_type iucv_packet_type = {
2259	.type = cpu_to_be16(ETH_P_AF_IUCV),
2260	.func = afiucv_hs_rcv,
2261};
2262
2263static 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
2301out_notifier:
2302	if (pr_iucv)
2303		pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2304out_sock:
2305	sock_unregister(PF_IUCV);
2306out_proto:
2307	proto_unregister(&iucv_proto);
2308out:
2309	return err;
2310}
2311
2312static 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
2323module_init(afiucv_init);
2324module_exit(afiucv_exit);
2325
2326MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2327MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2328MODULE_VERSION(VERSION);
2329MODULE_LICENSE("GPL");
2330MODULE_ALIAS_NETPROTO(PF_IUCV);
2331