Merge tag 'for-linus-20181012' of git://git.kernel.dk/linux-block
[linux-2.6-microblaze.git] / net / iucv / af_iucv.c
1 /*
2  *  IUCV protocol stack for Linux on zSeries
3  *
4  *  Copyright IBM Corp. 2006, 2009
5  *
6  *  Author(s):  Jennifer Hunt <jenhunt@us.ibm.com>
7  *              Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
8  *  PM functions:
9  *              Ursula Braun <ursula.braun@de.ibm.com>
10  */
11
12 #define KMSG_COMPONENT "af_iucv"
13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
14
15 #include <linux/module.h>
16 #include <linux/types.h>
17 #include <linux/list.h>
18 #include <linux/errno.h>
19 #include <linux/kernel.h>
20 #include <linux/sched/signal.h>
21 #include <linux/slab.h>
22 #include <linux/skbuff.h>
23 #include <linux/init.h>
24 #include <linux/poll.h>
25 #include <linux/security.h>
26 #include <net/sock.h>
27 #include <asm/ebcdic.h>
28 #include <asm/cpcmd.h>
29 #include <linux/kmod.h>
30
31 #include <net/iucv/af_iucv.h>
32
33 #define VERSION "1.2"
34
35 static char iucv_userid[80];
36
37 static const struct proto_ops iucv_sock_ops;
38
39 static struct proto iucv_proto = {
40         .name           = "AF_IUCV",
41         .owner          = THIS_MODULE,
42         .obj_size       = sizeof(struct iucv_sock),
43 };
44
45 static struct iucv_interface *pr_iucv;
46
47 /* special AF_IUCV IPRM messages */
48 static const u8 iprm_shutdown[8] =
49         {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
50
51 #define TRGCLS_SIZE     (sizeof(((struct iucv_message *)0)->class))
52
53 #define __iucv_sock_wait(sk, condition, timeo, ret)                     \
54 do {                                                                    \
55         DEFINE_WAIT(__wait);                                            \
56         long __timeo = timeo;                                           \
57         ret = 0;                                                        \
58         prepare_to_wait(sk_sleep(sk), &__wait, TASK_INTERRUPTIBLE);     \
59         while (!(condition)) {                                          \
60                 if (!__timeo) {                                         \
61                         ret = -EAGAIN;                                  \
62                         break;                                          \
63                 }                                                       \
64                 if (signal_pending(current)) {                          \
65                         ret = sock_intr_errno(__timeo);                 \
66                         break;                                          \
67                 }                                                       \
68                 release_sock(sk);                                       \
69                 __timeo = schedule_timeout(__timeo);                    \
70                 lock_sock(sk);                                          \
71                 ret = sock_error(sk);                                   \
72                 if (ret)                                                \
73                         break;                                          \
74         }                                                               \
75         finish_wait(sk_sleep(sk), &__wait);                             \
76 } while (0)
77
78 #define iucv_sock_wait(sk, condition, timeo)                            \
79 ({                                                                      \
80         int __ret = 0;                                                  \
81         if (!(condition))                                               \
82                 __iucv_sock_wait(sk, condition, timeo, __ret);          \
83         __ret;                                                          \
84 })
85
86 static void iucv_sock_kill(struct sock *sk);
87 static void iucv_sock_close(struct sock *sk);
88 static void iucv_sever_path(struct sock *, int);
89
90 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
91         struct packet_type *pt, struct net_device *orig_dev);
92 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
93                    struct sk_buff *skb, u8 flags);
94 static void afiucv_hs_callback_txnotify(struct sk_buff *, enum iucv_tx_notify);
95
96 /* Call Back functions */
97 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
98 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
99 static void iucv_callback_connack(struct iucv_path *, u8 *);
100 static int iucv_callback_connreq(struct iucv_path *, u8 *, u8 *);
101 static void iucv_callback_connrej(struct iucv_path *, u8 *);
102 static void iucv_callback_shutdown(struct iucv_path *, u8 *);
103
104 static struct iucv_sock_list iucv_sk_list = {
105         .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
106         .autobind_name = ATOMIC_INIT(0)
107 };
108
109 static struct iucv_handler af_iucv_handler = {
110         .path_pending     = iucv_callback_connreq,
111         .path_complete    = iucv_callback_connack,
112         .path_severed     = iucv_callback_connrej,
113         .message_pending  = iucv_callback_rx,
114         .message_complete = iucv_callback_txdone,
115         .path_quiesced    = iucv_callback_shutdown,
116 };
117
118 static inline void high_nmcpy(unsigned char *dst, char *src)
119 {
120        memcpy(dst, src, 8);
121 }
122
123 static inline void low_nmcpy(unsigned char *dst, char *src)
124 {
125        memcpy(&dst[8], src, 8);
126 }
127
128 static int afiucv_pm_prepare(struct device *dev)
129 {
130 #ifdef CONFIG_PM_DEBUG
131         printk(KERN_WARNING "afiucv_pm_prepare\n");
132 #endif
133         return 0;
134 }
135
136 static void afiucv_pm_complete(struct device *dev)
137 {
138 #ifdef CONFIG_PM_DEBUG
139         printk(KERN_WARNING "afiucv_pm_complete\n");
140 #endif
141 }
142
143 /**
144  * afiucv_pm_freeze() - Freeze PM callback
145  * @dev:        AFIUCV dummy device
146  *
147  * Sever all established IUCV communication pathes
148  */
149 static int afiucv_pm_freeze(struct device *dev)
150 {
151         struct iucv_sock *iucv;
152         struct sock *sk;
153
154 #ifdef CONFIG_PM_DEBUG
155         printk(KERN_WARNING "afiucv_pm_freeze\n");
156 #endif
157         read_lock(&iucv_sk_list.lock);
158         sk_for_each(sk, &iucv_sk_list.head) {
159                 iucv = iucv_sk(sk);
160                 switch (sk->sk_state) {
161                 case IUCV_DISCONN:
162                 case IUCV_CLOSING:
163                 case IUCV_CONNECTED:
164                         iucv_sever_path(sk, 0);
165                         break;
166                 case IUCV_OPEN:
167                 case IUCV_BOUND:
168                 case IUCV_LISTEN:
169                 case IUCV_CLOSED:
170                 default:
171                         break;
172                 }
173                 skb_queue_purge(&iucv->send_skb_q);
174                 skb_queue_purge(&iucv->backlog_skb_q);
175         }
176         read_unlock(&iucv_sk_list.lock);
177         return 0;
178 }
179
180 /**
181  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
182  * @dev:        AFIUCV dummy device
183  *
184  * socket clean up after freeze
185  */
186 static int afiucv_pm_restore_thaw(struct device *dev)
187 {
188         struct sock *sk;
189
190 #ifdef CONFIG_PM_DEBUG
191         printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
192 #endif
193         read_lock(&iucv_sk_list.lock);
194         sk_for_each(sk, &iucv_sk_list.head) {
195                 switch (sk->sk_state) {
196                 case IUCV_CONNECTED:
197                         sk->sk_err = EPIPE;
198                         sk->sk_state = IUCV_DISCONN;
199                         sk->sk_state_change(sk);
200                         break;
201                 case IUCV_DISCONN:
202                 case IUCV_CLOSING:
203                 case IUCV_LISTEN:
204                 case IUCV_BOUND:
205                 case IUCV_OPEN:
206                 default:
207                         break;
208                 }
209         }
210         read_unlock(&iucv_sk_list.lock);
211         return 0;
212 }
213
214 static const struct dev_pm_ops afiucv_pm_ops = {
215         .prepare = afiucv_pm_prepare,
216         .complete = afiucv_pm_complete,
217         .freeze = afiucv_pm_freeze,
218         .thaw = afiucv_pm_restore_thaw,
219         .restore = afiucv_pm_restore_thaw,
220 };
221
222 static struct device_driver af_iucv_driver = {
223         .owner = THIS_MODULE,
224         .name = "afiucv",
225         .bus  = NULL,
226         .pm   = &afiucv_pm_ops,
227 };
228
229 /* dummy device used as trigger for PM functions */
230 static struct device *af_iucv_dev;
231
232 /**
233  * iucv_msg_length() - Returns the length of an iucv message.
234  * @msg:        Pointer to struct iucv_message, MUST NOT be NULL
235  *
236  * The function returns the length of the specified iucv message @msg of data
237  * stored in a buffer and of data stored in the parameter list (PRMDATA).
238  *
239  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
240  * data:
241  *      PRMDATA[0..6]   socket data (max 7 bytes);
242  *      PRMDATA[7]      socket data length value (len is 0xff - PRMDATA[7])
243  *
244  * The socket data length is computed by subtracting the socket data length
245  * value from 0xFF.
246  * If the socket data len is greater 7, then PRMDATA can be used for special
247  * notifications (see iucv_sock_shutdown); and further,
248  * if the socket data len is > 7, the function returns 8.
249  *
250  * Use this function to allocate socket buffers to store iucv message data.
251  */
252 static inline size_t iucv_msg_length(struct iucv_message *msg)
253 {
254         size_t datalen;
255
256         if (msg->flags & IUCV_IPRMDATA) {
257                 datalen = 0xff - msg->rmmsg[7];
258                 return (datalen < 8) ? datalen : 8;
259         }
260         return msg->length;
261 }
262
263 /**
264  * iucv_sock_in_state() - check for specific states
265  * @sk:         sock structure
266  * @state:      first iucv sk state
267  * @state:      second iucv sk state
268  *
269  * Returns true if the socket in either in the first or second state.
270  */
271 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
272 {
273         return (sk->sk_state == state || sk->sk_state == state2);
274 }
275
276 /**
277  * iucv_below_msglim() - function to check if messages can be sent
278  * @sk:         sock structure
279  *
280  * Returns true if the send queue length is lower than the message limit.
281  * Always returns true if the socket is not connected (no iucv path for
282  * checking the message limit).
283  */
284 static inline int iucv_below_msglim(struct sock *sk)
285 {
286         struct iucv_sock *iucv = iucv_sk(sk);
287
288         if (sk->sk_state != IUCV_CONNECTED)
289                 return 1;
290         if (iucv->transport == AF_IUCV_TRANS_IUCV)
291                 return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
292         else
293                 return ((atomic_read(&iucv->msg_sent) < iucv->msglimit_peer) &&
294                         (atomic_read(&iucv->pendings) <= 0));
295 }
296
297 /**
298  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
299  */
300 static void iucv_sock_wake_msglim(struct sock *sk)
301 {
302         struct socket_wq *wq;
303
304         rcu_read_lock();
305         wq = rcu_dereference(sk->sk_wq);
306         if (skwq_has_sleeper(wq))
307                 wake_up_interruptible_all(&wq->wait);
308         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
309         rcu_read_unlock();
310 }
311
312 /**
313  * afiucv_hs_send() - send a message through HiperSockets transport
314  */
315 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
316                    struct sk_buff *skb, u8 flags)
317 {
318         struct iucv_sock *iucv = iucv_sk(sock);
319         struct af_iucv_trans_hdr *phs_hdr;
320         struct sk_buff *nskb;
321         int err, confirm_recv = 0;
322
323         memset(skb->head, 0, ETH_HLEN);
324         phs_hdr = skb_push(skb, sizeof(struct af_iucv_trans_hdr));
325         skb_reset_mac_header(skb);
326         skb_reset_network_header(skb);
327         skb_push(skb, ETH_HLEN);
328         skb_reset_mac_header(skb);
329         memset(phs_hdr, 0, sizeof(struct af_iucv_trans_hdr));
330
331         phs_hdr->magic = ETH_P_AF_IUCV;
332         phs_hdr->version = 1;
333         phs_hdr->flags = flags;
334         if (flags == AF_IUCV_FLAG_SYN)
335                 phs_hdr->window = iucv->msglimit;
336         else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
337                 confirm_recv = atomic_read(&iucv->msg_recv);
338                 phs_hdr->window = confirm_recv;
339                 if (confirm_recv)
340                         phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
341         }
342         memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
343         memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
344         memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
345         memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
346         ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
347         ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
348         ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
349         ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
350         if (imsg)
351                 memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
352
353         skb->dev = iucv->hs_dev;
354         if (!skb->dev) {
355                 err = -ENODEV;
356                 goto err_free;
357         }
358         if (!(skb->dev->flags & IFF_UP) || !netif_carrier_ok(skb->dev)) {
359                 err = -ENETDOWN;
360                 goto err_free;
361         }
362         if (skb->len > skb->dev->mtu) {
363                 if (sock->sk_type == SOCK_SEQPACKET) {
364                         err = -EMSGSIZE;
365                         goto err_free;
366                 }
367                 skb_trim(skb, skb->dev->mtu);
368         }
369         skb->protocol = cpu_to_be16(ETH_P_AF_IUCV);
370         nskb = skb_clone(skb, GFP_ATOMIC);
371         if (!nskb) {
372                 err = -ENOMEM;
373                 goto err_free;
374         }
375
376         skb_queue_tail(&iucv->send_skb_q, nskb);
377         err = dev_queue_xmit(skb);
378         if (net_xmit_eval(err)) {
379                 skb_unlink(nskb, &iucv->send_skb_q);
380                 kfree_skb(nskb);
381         } else {
382                 atomic_sub(confirm_recv, &iucv->msg_recv);
383                 WARN_ON(atomic_read(&iucv->msg_recv) < 0);
384         }
385         return net_xmit_eval(err);
386
387 err_free:
388         kfree_skb(skb);
389         return err;
390 }
391
392 static struct sock *__iucv_get_sock_by_name(char *nm)
393 {
394         struct sock *sk;
395
396         sk_for_each(sk, &iucv_sk_list.head)
397                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
398                         return sk;
399
400         return NULL;
401 }
402
403 static void iucv_sock_destruct(struct sock *sk)
404 {
405         skb_queue_purge(&sk->sk_receive_queue);
406         skb_queue_purge(&sk->sk_error_queue);
407
408         sk_mem_reclaim(sk);
409
410         if (!sock_flag(sk, SOCK_DEAD)) {
411                 pr_err("Attempt to release alive iucv socket %p\n", sk);
412                 return;
413         }
414
415         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
416         WARN_ON(refcount_read(&sk->sk_wmem_alloc));
417         WARN_ON(sk->sk_wmem_queued);
418         WARN_ON(sk->sk_forward_alloc);
419 }
420
421 /* Cleanup Listen */
422 static void iucv_sock_cleanup_listen(struct sock *parent)
423 {
424         struct sock *sk;
425
426         /* Close non-accepted connections */
427         while ((sk = iucv_accept_dequeue(parent, NULL))) {
428                 iucv_sock_close(sk);
429                 iucv_sock_kill(sk);
430         }
431
432         parent->sk_state = IUCV_CLOSED;
433 }
434
435 /* Kill socket (only if zapped and orphaned) */
436 static void iucv_sock_kill(struct sock *sk)
437 {
438         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
439                 return;
440
441         iucv_sock_unlink(&iucv_sk_list, sk);
442         sock_set_flag(sk, SOCK_DEAD);
443         sock_put(sk);
444 }
445
446 /* Terminate an IUCV path */
447 static void iucv_sever_path(struct sock *sk, int with_user_data)
448 {
449         unsigned char user_data[16];
450         struct iucv_sock *iucv = iucv_sk(sk);
451         struct iucv_path *path = iucv->path;
452
453         if (iucv->path) {
454                 iucv->path = NULL;
455                 if (with_user_data) {
456                         low_nmcpy(user_data, iucv->src_name);
457                         high_nmcpy(user_data, iucv->dst_name);
458                         ASCEBC(user_data, sizeof(user_data));
459                         pr_iucv->path_sever(path, user_data);
460                 } else
461                         pr_iucv->path_sever(path, NULL);
462                 iucv_path_free(path);
463         }
464 }
465
466 /* Send controlling flags through an IUCV socket for HIPER transport */
467 static int iucv_send_ctrl(struct sock *sk, u8 flags)
468 {
469         int err = 0;
470         int blen;
471         struct sk_buff *skb;
472         u8 shutdown = 0;
473
474         blen = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
475         if (sk->sk_shutdown & SEND_SHUTDOWN) {
476                 /* controlling flags should be sent anyway */
477                 shutdown = sk->sk_shutdown;
478                 sk->sk_shutdown &= RCV_SHUTDOWN;
479         }
480         skb = sock_alloc_send_skb(sk, blen, 1, &err);
481         if (skb) {
482                 skb_reserve(skb, blen);
483                 err = afiucv_hs_send(NULL, sk, skb, flags);
484         }
485         if (shutdown)
486                 sk->sk_shutdown = shutdown;
487         return err;
488 }
489
490 /* Close an IUCV socket */
491 static void iucv_sock_close(struct sock *sk)
492 {
493         struct iucv_sock *iucv = iucv_sk(sk);
494         unsigned long timeo;
495         int err = 0;
496
497         lock_sock(sk);
498
499         switch (sk->sk_state) {
500         case IUCV_LISTEN:
501                 iucv_sock_cleanup_listen(sk);
502                 break;
503
504         case IUCV_CONNECTED:
505                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
506                         err = iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
507                         sk->sk_state = IUCV_DISCONN;
508                         sk->sk_state_change(sk);
509                 }
510         case IUCV_DISCONN:   /* fall through */
511                 sk->sk_state = IUCV_CLOSING;
512                 sk->sk_state_change(sk);
513
514                 if (!err && !skb_queue_empty(&iucv->send_skb_q)) {
515                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
516                                 timeo = sk->sk_lingertime;
517                         else
518                                 timeo = IUCV_DISCONN_TIMEOUT;
519                         iucv_sock_wait(sk,
520                                         iucv_sock_in_state(sk, IUCV_CLOSED, 0),
521                                         timeo);
522                 }
523
524         case IUCV_CLOSING:   /* fall through */
525                 sk->sk_state = IUCV_CLOSED;
526                 sk->sk_state_change(sk);
527
528                 sk->sk_err = ECONNRESET;
529                 sk->sk_state_change(sk);
530
531                 skb_queue_purge(&iucv->send_skb_q);
532                 skb_queue_purge(&iucv->backlog_skb_q);
533
534         default:   /* fall through */
535                 iucv_sever_path(sk, 1);
536         }
537
538         if (iucv->hs_dev) {
539                 dev_put(iucv->hs_dev);
540                 iucv->hs_dev = NULL;
541                 sk->sk_bound_dev_if = 0;
542         }
543
544         /* mark socket for deletion by iucv_sock_kill() */
545         sock_set_flag(sk, SOCK_ZAPPED);
546
547         release_sock(sk);
548 }
549
550 static void iucv_sock_init(struct sock *sk, struct sock *parent)
551 {
552         if (parent) {
553                 sk->sk_type = parent->sk_type;
554                 security_sk_clone(parent, sk);
555         }
556 }
557
558 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio, int kern)
559 {
560         struct sock *sk;
561         struct iucv_sock *iucv;
562
563         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto, kern);
564         if (!sk)
565                 return NULL;
566         iucv = iucv_sk(sk);
567
568         sock_init_data(sock, sk);
569         INIT_LIST_HEAD(&iucv->accept_q);
570         spin_lock_init(&iucv->accept_q_lock);
571         skb_queue_head_init(&iucv->send_skb_q);
572         INIT_LIST_HEAD(&iucv->message_q.list);
573         spin_lock_init(&iucv->message_q.lock);
574         skb_queue_head_init(&iucv->backlog_skb_q);
575         iucv->send_tag = 0;
576         atomic_set(&iucv->pendings, 0);
577         iucv->flags = 0;
578         iucv->msglimit = 0;
579         atomic_set(&iucv->msg_sent, 0);
580         atomic_set(&iucv->msg_recv, 0);
581         iucv->path = NULL;
582         iucv->sk_txnotify = afiucv_hs_callback_txnotify;
583         memset(&iucv->src_user_id , 0, 32);
584         if (pr_iucv)
585                 iucv->transport = AF_IUCV_TRANS_IUCV;
586         else
587                 iucv->transport = AF_IUCV_TRANS_HIPER;
588
589         sk->sk_destruct = iucv_sock_destruct;
590         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
591         sk->sk_allocation = GFP_DMA;
592
593         sock_reset_flag(sk, SOCK_ZAPPED);
594
595         sk->sk_protocol = proto;
596         sk->sk_state    = IUCV_OPEN;
597
598         iucv_sock_link(&iucv_sk_list, sk);
599         return sk;
600 }
601
602 /* Create an IUCV socket */
603 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
604                             int kern)
605 {
606         struct sock *sk;
607
608         if (protocol && protocol != PF_IUCV)
609                 return -EPROTONOSUPPORT;
610
611         sock->state = SS_UNCONNECTED;
612
613         switch (sock->type) {
614         case SOCK_STREAM:
615                 sock->ops = &iucv_sock_ops;
616                 break;
617         case SOCK_SEQPACKET:
618                 /* currently, proto ops can handle both sk types */
619                 sock->ops = &iucv_sock_ops;
620                 break;
621         default:
622                 return -ESOCKTNOSUPPORT;
623         }
624
625         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL, kern);
626         if (!sk)
627                 return -ENOMEM;
628
629         iucv_sock_init(sk, NULL);
630
631         return 0;
632 }
633
634 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
635 {
636         write_lock_bh(&l->lock);
637         sk_add_node(sk, &l->head);
638         write_unlock_bh(&l->lock);
639 }
640
641 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
642 {
643         write_lock_bh(&l->lock);
644         sk_del_node_init(sk);
645         write_unlock_bh(&l->lock);
646 }
647
648 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
649 {
650         unsigned long flags;
651         struct iucv_sock *par = iucv_sk(parent);
652
653         sock_hold(sk);
654         spin_lock_irqsave(&par->accept_q_lock, flags);
655         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
656         spin_unlock_irqrestore(&par->accept_q_lock, flags);
657         iucv_sk(sk)->parent = parent;
658         sk_acceptq_added(parent);
659 }
660
661 void iucv_accept_unlink(struct sock *sk)
662 {
663         unsigned long flags;
664         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
665
666         spin_lock_irqsave(&par->accept_q_lock, flags);
667         list_del_init(&iucv_sk(sk)->accept_q);
668         spin_unlock_irqrestore(&par->accept_q_lock, flags);
669         sk_acceptq_removed(iucv_sk(sk)->parent);
670         iucv_sk(sk)->parent = NULL;
671         sock_put(sk);
672 }
673
674 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
675 {
676         struct iucv_sock *isk, *n;
677         struct sock *sk;
678
679         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
680                 sk = (struct sock *) isk;
681                 lock_sock(sk);
682
683                 if (sk->sk_state == IUCV_CLOSED) {
684                         iucv_accept_unlink(sk);
685                         release_sock(sk);
686                         continue;
687                 }
688
689                 if (sk->sk_state == IUCV_CONNECTED ||
690                     sk->sk_state == IUCV_DISCONN ||
691                     !newsock) {
692                         iucv_accept_unlink(sk);
693                         if (newsock)
694                                 sock_graft(sk, newsock);
695
696                         release_sock(sk);
697                         return sk;
698                 }
699
700                 release_sock(sk);
701         }
702         return NULL;
703 }
704
705 static void __iucv_auto_name(struct iucv_sock *iucv)
706 {
707         char name[12];
708
709         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
710         while (__iucv_get_sock_by_name(name)) {
711                 sprintf(name, "%08x",
712                         atomic_inc_return(&iucv_sk_list.autobind_name));
713         }
714         memcpy(iucv->src_name, name, 8);
715 }
716
717 /* Bind an unbound socket */
718 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
719                           int addr_len)
720 {
721         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
722         struct sock *sk = sock->sk;
723         struct iucv_sock *iucv;
724         int err = 0;
725         struct net_device *dev;
726         char uid[9];
727
728         /* Verify the input sockaddr */
729         if (addr_len < sizeof(struct sockaddr_iucv) ||
730             addr->sa_family != AF_IUCV)
731                 return -EINVAL;
732
733         lock_sock(sk);
734         if (sk->sk_state != IUCV_OPEN) {
735                 err = -EBADFD;
736                 goto done;
737         }
738
739         write_lock_bh(&iucv_sk_list.lock);
740
741         iucv = iucv_sk(sk);
742         if (__iucv_get_sock_by_name(sa->siucv_name)) {
743                 err = -EADDRINUSE;
744                 goto done_unlock;
745         }
746         if (iucv->path)
747                 goto done_unlock;
748
749         /* Bind the socket */
750         if (pr_iucv)
751                 if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
752                         goto vm_bind; /* VM IUCV transport */
753
754         /* try hiper transport */
755         memcpy(uid, sa->siucv_user_id, sizeof(uid));
756         ASCEBC(uid, 8);
757         rcu_read_lock();
758         for_each_netdev_rcu(&init_net, dev) {
759                 if (!memcmp(dev->perm_addr, uid, 8)) {
760                         memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
761                         /* Check for unitialized siucv_name */
762                         if (strncmp(sa->siucv_name, "        ", 8) == 0)
763                                 __iucv_auto_name(iucv);
764                         else
765                                 memcpy(iucv->src_name, sa->siucv_name, 8);
766                         sk->sk_bound_dev_if = dev->ifindex;
767                         iucv->hs_dev = dev;
768                         dev_hold(dev);
769                         sk->sk_state = IUCV_BOUND;
770                         iucv->transport = AF_IUCV_TRANS_HIPER;
771                         if (!iucv->msglimit)
772                                 iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
773                         rcu_read_unlock();
774                         goto done_unlock;
775                 }
776         }
777         rcu_read_unlock();
778 vm_bind:
779         if (pr_iucv) {
780                 /* use local userid for backward compat */
781                 memcpy(iucv->src_name, sa->siucv_name, 8);
782                 memcpy(iucv->src_user_id, iucv_userid, 8);
783                 sk->sk_state = IUCV_BOUND;
784                 iucv->transport = AF_IUCV_TRANS_IUCV;
785                 if (!iucv->msglimit)
786                         iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
787                 goto done_unlock;
788         }
789         /* found no dev to bind */
790         err = -ENODEV;
791 done_unlock:
792         /* Release the socket list lock */
793         write_unlock_bh(&iucv_sk_list.lock);
794 done:
795         release_sock(sk);
796         return err;
797 }
798
799 /* Automatically bind an unbound socket */
800 static int iucv_sock_autobind(struct sock *sk)
801 {
802         struct iucv_sock *iucv = iucv_sk(sk);
803         int err = 0;
804
805         if (unlikely(!pr_iucv))
806                 return -EPROTO;
807
808         memcpy(iucv->src_user_id, iucv_userid, 8);
809
810         write_lock_bh(&iucv_sk_list.lock);
811         __iucv_auto_name(iucv);
812         write_unlock_bh(&iucv_sk_list.lock);
813
814         if (!iucv->msglimit)
815                 iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
816
817         return err;
818 }
819
820 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
821 {
822         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
823         struct sock *sk = sock->sk;
824         struct iucv_sock *iucv = iucv_sk(sk);
825         unsigned char user_data[16];
826         int err;
827
828         high_nmcpy(user_data, sa->siucv_name);
829         low_nmcpy(user_data, iucv->src_name);
830         ASCEBC(user_data, sizeof(user_data));
831
832         /* Create path. */
833         iucv->path = iucv_path_alloc(iucv->msglimit,
834                                      IUCV_IPRMDATA, GFP_KERNEL);
835         if (!iucv->path) {
836                 err = -ENOMEM;
837                 goto done;
838         }
839         err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
840                                     sa->siucv_user_id, NULL, user_data,
841                                     sk);
842         if (err) {
843                 iucv_path_free(iucv->path);
844                 iucv->path = NULL;
845                 switch (err) {
846                 case 0x0b:      /* Target communicator is not logged on */
847                         err = -ENETUNREACH;
848                         break;
849                 case 0x0d:      /* Max connections for this guest exceeded */
850                 case 0x0e:      /* Max connections for target guest exceeded */
851                         err = -EAGAIN;
852                         break;
853                 case 0x0f:      /* Missing IUCV authorization */
854                         err = -EACCES;
855                         break;
856                 default:
857                         err = -ECONNREFUSED;
858                         break;
859                 }
860         }
861 done:
862         return err;
863 }
864
865 /* Connect an unconnected socket */
866 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
867                              int alen, int flags)
868 {
869         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
870         struct sock *sk = sock->sk;
871         struct iucv_sock *iucv = iucv_sk(sk);
872         int err;
873
874         if (alen < sizeof(struct sockaddr_iucv) || addr->sa_family != AF_IUCV)
875                 return -EINVAL;
876
877         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
878                 return -EBADFD;
879
880         if (sk->sk_state == IUCV_OPEN &&
881             iucv->transport == AF_IUCV_TRANS_HIPER)
882                 return -EBADFD; /* explicit bind required */
883
884         if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
885                 return -EINVAL;
886
887         if (sk->sk_state == IUCV_OPEN) {
888                 err = iucv_sock_autobind(sk);
889                 if (unlikely(err))
890                         return err;
891         }
892
893         lock_sock(sk);
894
895         /* Set the destination information */
896         memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
897         memcpy(iucv->dst_name, sa->siucv_name, 8);
898
899         if (iucv->transport == AF_IUCV_TRANS_HIPER)
900                 err = iucv_send_ctrl(sock->sk, AF_IUCV_FLAG_SYN);
901         else
902                 err = afiucv_path_connect(sock, addr);
903         if (err)
904                 goto done;
905
906         if (sk->sk_state != IUCV_CONNECTED)
907                 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
908                                                             IUCV_DISCONN),
909                                      sock_sndtimeo(sk, flags & O_NONBLOCK));
910
911         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
912                 err = -ECONNREFUSED;
913
914         if (err && iucv->transport == AF_IUCV_TRANS_IUCV)
915                 iucv_sever_path(sk, 0);
916
917 done:
918         release_sock(sk);
919         return err;
920 }
921
922 /* Move a socket into listening state. */
923 static int iucv_sock_listen(struct socket *sock, int backlog)
924 {
925         struct sock *sk = sock->sk;
926         int err;
927
928         lock_sock(sk);
929
930         err = -EINVAL;
931         if (sk->sk_state != IUCV_BOUND)
932                 goto done;
933
934         if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
935                 goto done;
936
937         sk->sk_max_ack_backlog = backlog;
938         sk->sk_ack_backlog = 0;
939         sk->sk_state = IUCV_LISTEN;
940         err = 0;
941
942 done:
943         release_sock(sk);
944         return err;
945 }
946
947 /* Accept a pending connection */
948 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
949                             int flags, bool kern)
950 {
951         DECLARE_WAITQUEUE(wait, current);
952         struct sock *sk = sock->sk, *nsk;
953         long timeo;
954         int err = 0;
955
956         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
957
958         if (sk->sk_state != IUCV_LISTEN) {
959                 err = -EBADFD;
960                 goto done;
961         }
962
963         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
964
965         /* Wait for an incoming connection */
966         add_wait_queue_exclusive(sk_sleep(sk), &wait);
967         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
968                 set_current_state(TASK_INTERRUPTIBLE);
969                 if (!timeo) {
970                         err = -EAGAIN;
971                         break;
972                 }
973
974                 release_sock(sk);
975                 timeo = schedule_timeout(timeo);
976                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
977
978                 if (sk->sk_state != IUCV_LISTEN) {
979                         err = -EBADFD;
980                         break;
981                 }
982
983                 if (signal_pending(current)) {
984                         err = sock_intr_errno(timeo);
985                         break;
986                 }
987         }
988
989         set_current_state(TASK_RUNNING);
990         remove_wait_queue(sk_sleep(sk), &wait);
991
992         if (err)
993                 goto done;
994
995         newsock->state = SS_CONNECTED;
996
997 done:
998         release_sock(sk);
999         return err;
1000 }
1001
1002 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
1003                              int peer)
1004 {
1005         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
1006         struct sock *sk = sock->sk;
1007         struct iucv_sock *iucv = iucv_sk(sk);
1008
1009         addr->sa_family = AF_IUCV;
1010
1011         if (peer) {
1012                 memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
1013                 memcpy(siucv->siucv_name, iucv->dst_name, 8);
1014         } else {
1015                 memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
1016                 memcpy(siucv->siucv_name, iucv->src_name, 8);
1017         }
1018         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
1019         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
1020         memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
1021
1022         return sizeof(struct sockaddr_iucv);
1023 }
1024
1025 /**
1026  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
1027  * @path:       IUCV path
1028  * @msg:        Pointer to a struct iucv_message
1029  * @skb:        The socket data to send, skb->len MUST BE <= 7
1030  *
1031  * Send the socket data in the parameter list in the iucv message
1032  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
1033  * list and the socket data len at index 7 (last byte).
1034  * See also iucv_msg_length().
1035  *
1036  * Returns the error code from the iucv_message_send() call.
1037  */
1038 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
1039                           struct sk_buff *skb)
1040 {
1041         u8 prmdata[8];
1042
1043         memcpy(prmdata, (void *) skb->data, skb->len);
1044         prmdata[7] = 0xff - (u8) skb->len;
1045         return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
1046                                  (void *) prmdata, 8);
1047 }
1048
1049 static int iucv_sock_sendmsg(struct socket *sock, struct msghdr *msg,
1050                              size_t len)
1051 {
1052         struct sock *sk = sock->sk;
1053         struct iucv_sock *iucv = iucv_sk(sk);
1054         size_t headroom = 0;
1055         size_t linear;
1056         struct sk_buff *skb;
1057         struct iucv_message txmsg = {0};
1058         struct cmsghdr *cmsg;
1059         int cmsg_done;
1060         long timeo;
1061         char user_id[9];
1062         char appl_id[9];
1063         int err;
1064         int noblock = msg->msg_flags & MSG_DONTWAIT;
1065
1066         err = sock_error(sk);
1067         if (err)
1068                 return err;
1069
1070         if (msg->msg_flags & MSG_OOB)
1071                 return -EOPNOTSUPP;
1072
1073         /* SOCK_SEQPACKET: we do not support segmented records */
1074         if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
1075                 return -EOPNOTSUPP;
1076
1077         lock_sock(sk);
1078
1079         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1080                 err = -EPIPE;
1081                 goto out;
1082         }
1083
1084         /* Return if the socket is not in connected state */
1085         if (sk->sk_state != IUCV_CONNECTED) {
1086                 err = -ENOTCONN;
1087                 goto out;
1088         }
1089
1090         /* initialize defaults */
1091         cmsg_done   = 0;        /* check for duplicate headers */
1092         txmsg.class = 0;
1093
1094         /* iterate over control messages */
1095         for_each_cmsghdr(cmsg, msg) {
1096                 if (!CMSG_OK(msg, cmsg)) {
1097                         err = -EINVAL;
1098                         goto out;
1099                 }
1100
1101                 if (cmsg->cmsg_level != SOL_IUCV)
1102                         continue;
1103
1104                 if (cmsg->cmsg_type & cmsg_done) {
1105                         err = -EINVAL;
1106                         goto out;
1107                 }
1108                 cmsg_done |= cmsg->cmsg_type;
1109
1110                 switch (cmsg->cmsg_type) {
1111                 case SCM_IUCV_TRGCLS:
1112                         if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
1113                                 err = -EINVAL;
1114                                 goto out;
1115                         }
1116
1117                         /* set iucv message target class */
1118                         memcpy(&txmsg.class,
1119                                 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
1120
1121                         break;
1122
1123                 default:
1124                         err = -EINVAL;
1125                         goto out;
1126                 }
1127         }
1128
1129         /* allocate one skb for each iucv message:
1130          * this is fine for SOCK_SEQPACKET (unless we want to support
1131          * segmented records using the MSG_EOR flag), but
1132          * for SOCK_STREAM we might want to improve it in future */
1133         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1134                 headroom = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
1135                 linear = len;
1136         } else {
1137                 if (len < PAGE_SIZE) {
1138                         linear = len;
1139                 } else {
1140                         /* In nonlinear "classic" iucv skb,
1141                          * reserve space for iucv_array
1142                          */
1143                         headroom = sizeof(struct iucv_array) *
1144                                    (MAX_SKB_FRAGS + 1);
1145                         linear = PAGE_SIZE - headroom;
1146                 }
1147         }
1148         skb = sock_alloc_send_pskb(sk, headroom + linear, len - linear,
1149                                    noblock, &err, 0);
1150         if (!skb)
1151                 goto out;
1152         if (headroom)
1153                 skb_reserve(skb, headroom);
1154         skb_put(skb, linear);
1155         skb->len = len;
1156         skb->data_len = len - linear;
1157         err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, len);
1158         if (err)
1159                 goto fail;
1160
1161         /* wait if outstanding messages for iucv path has reached */
1162         timeo = sock_sndtimeo(sk, noblock);
1163         err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1164         if (err)
1165                 goto fail;
1166
1167         /* return -ECONNRESET if the socket is no longer connected */
1168         if (sk->sk_state != IUCV_CONNECTED) {
1169                 err = -ECONNRESET;
1170                 goto fail;
1171         }
1172
1173         /* increment and save iucv message tag for msg_completion cbk */
1174         txmsg.tag = iucv->send_tag++;
1175         IUCV_SKB_CB(skb)->tag = txmsg.tag;
1176
1177         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1178                 atomic_inc(&iucv->msg_sent);
1179                 err = afiucv_hs_send(&txmsg, sk, skb, 0);
1180                 if (err) {
1181                         atomic_dec(&iucv->msg_sent);
1182                         goto out;
1183                 }
1184         } else { /* Classic VM IUCV transport */
1185                 skb_queue_tail(&iucv->send_skb_q, skb);
1186
1187                 if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags) &&
1188                     skb->len <= 7) {
1189                         err = iucv_send_iprm(iucv->path, &txmsg, skb);
1190
1191                         /* on success: there is no message_complete callback */
1192                         /* for an IPRMDATA msg; remove skb from send queue   */
1193                         if (err == 0) {
1194                                 skb_unlink(skb, &iucv->send_skb_q);
1195                                 kfree_skb(skb);
1196                         }
1197
1198                         /* this error should never happen since the     */
1199                         /* IUCV_IPRMDATA path flag is set... sever path */
1200                         if (err == 0x15) {
1201                                 pr_iucv->path_sever(iucv->path, NULL);
1202                                 skb_unlink(skb, &iucv->send_skb_q);
1203                                 err = -EPIPE;
1204                                 goto fail;
1205                         }
1206                 } else if (skb_is_nonlinear(skb)) {
1207                         struct iucv_array *iba = (struct iucv_array *)skb->head;
1208                         int i;
1209
1210                         /* skip iucv_array lying in the headroom */
1211                         iba[0].address = (u32)(addr_t)skb->data;
1212                         iba[0].length = (u32)skb_headlen(skb);
1213                         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1214                                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1215
1216                                 iba[i + 1].address =
1217                                         (u32)(addr_t)skb_frag_address(frag);
1218                                 iba[i + 1].length = (u32)skb_frag_size(frag);
1219                         }
1220                         err = pr_iucv->message_send(iucv->path, &txmsg,
1221                                                     IUCV_IPBUFLST, 0,
1222                                                     (void *)iba, skb->len);
1223                 } else { /* non-IPRM Linear skb */
1224                         err = pr_iucv->message_send(iucv->path, &txmsg,
1225                                         0, 0, (void *)skb->data, skb->len);
1226                 }
1227                 if (err) {
1228                         if (err == 3) {
1229                                 user_id[8] = 0;
1230                                 memcpy(user_id, iucv->dst_user_id, 8);
1231                                 appl_id[8] = 0;
1232                                 memcpy(appl_id, iucv->dst_name, 8);
1233                                 pr_err(
1234                 "Application %s on z/VM guest %s exceeds message limit\n",
1235                                         appl_id, user_id);
1236                                 err = -EAGAIN;
1237                         } else {
1238                                 err = -EPIPE;
1239                         }
1240                         skb_unlink(skb, &iucv->send_skb_q);
1241                         goto fail;
1242                 }
1243         }
1244
1245         release_sock(sk);
1246         return len;
1247
1248 fail:
1249         kfree_skb(skb);
1250 out:
1251         release_sock(sk);
1252         return err;
1253 }
1254
1255 static struct sk_buff *alloc_iucv_recv_skb(unsigned long len)
1256 {
1257         size_t headroom, linear;
1258         struct sk_buff *skb;
1259         int err;
1260
1261         if (len < PAGE_SIZE) {
1262                 headroom = 0;
1263                 linear = len;
1264         } else {
1265                 headroom = sizeof(struct iucv_array) * (MAX_SKB_FRAGS + 1);
1266                 linear = PAGE_SIZE - headroom;
1267         }
1268         skb = alloc_skb_with_frags(headroom + linear, len - linear,
1269                                    0, &err, GFP_ATOMIC | GFP_DMA);
1270         WARN_ONCE(!skb,
1271                   "alloc of recv iucv skb len=%lu failed with errcode=%d\n",
1272                   len, err);
1273         if (skb) {
1274                 if (headroom)
1275                         skb_reserve(skb, headroom);
1276                 skb_put(skb, linear);
1277                 skb->len = len;
1278                 skb->data_len = len - linear;
1279         }
1280         return skb;
1281 }
1282
1283 /* iucv_process_message() - Receive a single outstanding IUCV message
1284  *
1285  * Locking: must be called with message_q.lock held
1286  */
1287 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1288                                  struct iucv_path *path,
1289                                  struct iucv_message *msg)
1290 {
1291         int rc;
1292         unsigned int len;
1293
1294         len = iucv_msg_length(msg);
1295
1296         /* store msg target class in the second 4 bytes of skb ctrl buffer */
1297         /* Note: the first 4 bytes are reserved for msg tag */
1298         IUCV_SKB_CB(skb)->class = msg->class;
1299
1300         /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1301         if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1302                 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1303                         skb->data = NULL;
1304                         skb->len = 0;
1305                 }
1306         } else {
1307                 if (skb_is_nonlinear(skb)) {
1308                         struct iucv_array *iba = (struct iucv_array *)skb->head;
1309                         int i;
1310
1311                         iba[0].address = (u32)(addr_t)skb->data;
1312                         iba[0].length = (u32)skb_headlen(skb);
1313                         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1314                                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1315
1316                                 iba[i + 1].address =
1317                                         (u32)(addr_t)skb_frag_address(frag);
1318                                 iba[i + 1].length = (u32)skb_frag_size(frag);
1319                         }
1320                         rc = pr_iucv->message_receive(path, msg,
1321                                               IUCV_IPBUFLST,
1322                                               (void *)iba, len, NULL);
1323                 } else {
1324                         rc = pr_iucv->message_receive(path, msg,
1325                                               msg->flags & IUCV_IPRMDATA,
1326                                               skb->data, len, NULL);
1327                 }
1328                 if (rc) {
1329                         kfree_skb(skb);
1330                         return;
1331                 }
1332                 WARN_ON_ONCE(skb->len != len);
1333         }
1334
1335         IUCV_SKB_CB(skb)->offset = 0;
1336         if (sk_filter(sk, skb)) {
1337                 atomic_inc(&sk->sk_drops);      /* skb rejected by filter */
1338                 kfree_skb(skb);
1339                 return;
1340         }
1341         if (__sock_queue_rcv_skb(sk, skb))      /* handle rcv queue full */
1342                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
1343 }
1344
1345 /* iucv_process_message_q() - Process outstanding IUCV messages
1346  *
1347  * Locking: must be called with message_q.lock held
1348  */
1349 static void iucv_process_message_q(struct sock *sk)
1350 {
1351         struct iucv_sock *iucv = iucv_sk(sk);
1352         struct sk_buff *skb;
1353         struct sock_msg_q *p, *n;
1354
1355         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1356                 skb = alloc_iucv_recv_skb(iucv_msg_length(&p->msg));
1357                 if (!skb)
1358                         break;
1359                 iucv_process_message(sk, skb, p->path, &p->msg);
1360                 list_del(&p->list);
1361                 kfree(p);
1362                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1363                         break;
1364         }
1365 }
1366
1367 static int iucv_sock_recvmsg(struct socket *sock, struct msghdr *msg,
1368                              size_t len, int flags)
1369 {
1370         int noblock = flags & MSG_DONTWAIT;
1371         struct sock *sk = sock->sk;
1372         struct iucv_sock *iucv = iucv_sk(sk);
1373         unsigned int copied, rlen;
1374         struct sk_buff *skb, *rskb, *cskb;
1375         int err = 0;
1376         u32 offset;
1377
1378         if ((sk->sk_state == IUCV_DISCONN) &&
1379             skb_queue_empty(&iucv->backlog_skb_q) &&
1380             skb_queue_empty(&sk->sk_receive_queue) &&
1381             list_empty(&iucv->message_q.list))
1382                 return 0;
1383
1384         if (flags & (MSG_OOB))
1385                 return -EOPNOTSUPP;
1386
1387         /* receive/dequeue next skb:
1388          * the function understands MSG_PEEK and, thus, does not dequeue skb */
1389         skb = skb_recv_datagram(sk, flags, noblock, &err);
1390         if (!skb) {
1391                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1392                         return 0;
1393                 return err;
1394         }
1395
1396         offset = IUCV_SKB_CB(skb)->offset;
1397         rlen   = skb->len - offset;             /* real length of skb */
1398         copied = min_t(unsigned int, rlen, len);
1399         if (!rlen)
1400                 sk->sk_shutdown = sk->sk_shutdown | RCV_SHUTDOWN;
1401
1402         cskb = skb;
1403         if (skb_copy_datagram_msg(cskb, offset, msg, copied)) {
1404                 if (!(flags & MSG_PEEK))
1405                         skb_queue_head(&sk->sk_receive_queue, skb);
1406                 return -EFAULT;
1407         }
1408
1409         /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1410         if (sk->sk_type == SOCK_SEQPACKET) {
1411                 if (copied < rlen)
1412                         msg->msg_flags |= MSG_TRUNC;
1413                 /* each iucv message contains a complete record */
1414                 msg->msg_flags |= MSG_EOR;
1415         }
1416
1417         /* create control message to store iucv msg target class:
1418          * get the trgcls from the control buffer of the skb due to
1419          * fragmentation of original iucv message. */
1420         err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1421                        sizeof(IUCV_SKB_CB(skb)->class),
1422                        (void *)&IUCV_SKB_CB(skb)->class);
1423         if (err) {
1424                 if (!(flags & MSG_PEEK))
1425                         skb_queue_head(&sk->sk_receive_queue, skb);
1426                 return err;
1427         }
1428
1429         /* Mark read part of skb as used */
1430         if (!(flags & MSG_PEEK)) {
1431
1432                 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1433                 if (sk->sk_type == SOCK_STREAM) {
1434                         if (copied < rlen) {
1435                                 IUCV_SKB_CB(skb)->offset = offset + copied;
1436                                 skb_queue_head(&sk->sk_receive_queue, skb);
1437                                 goto done;
1438                         }
1439                 }
1440
1441                 kfree_skb(skb);
1442                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1443                         atomic_inc(&iucv->msg_recv);
1444                         if (atomic_read(&iucv->msg_recv) > iucv->msglimit) {
1445                                 WARN_ON(1);
1446                                 iucv_sock_close(sk);
1447                                 return -EFAULT;
1448                         }
1449                 }
1450
1451                 /* Queue backlog skbs */
1452                 spin_lock_bh(&iucv->message_q.lock);
1453                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1454                 while (rskb) {
1455                         IUCV_SKB_CB(rskb)->offset = 0;
1456                         if (__sock_queue_rcv_skb(sk, rskb)) {
1457                                 /* handle rcv queue full */
1458                                 skb_queue_head(&iucv->backlog_skb_q,
1459                                                 rskb);
1460                                 break;
1461                         }
1462                         rskb = skb_dequeue(&iucv->backlog_skb_q);
1463                 }
1464                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1465                         if (!list_empty(&iucv->message_q.list))
1466                                 iucv_process_message_q(sk);
1467                         if (atomic_read(&iucv->msg_recv) >=
1468                                                         iucv->msglimit / 2) {
1469                                 err = iucv_send_ctrl(sk, AF_IUCV_FLAG_WIN);
1470                                 if (err) {
1471                                         sk->sk_state = IUCV_DISCONN;
1472                                         sk->sk_state_change(sk);
1473                                 }
1474                         }
1475                 }
1476                 spin_unlock_bh(&iucv->message_q.lock);
1477         }
1478
1479 done:
1480         /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1481         if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1482                 copied = rlen;
1483
1484         return copied;
1485 }
1486
1487 static inline __poll_t iucv_accept_poll(struct sock *parent)
1488 {
1489         struct iucv_sock *isk, *n;
1490         struct sock *sk;
1491
1492         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1493                 sk = (struct sock *) isk;
1494
1495                 if (sk->sk_state == IUCV_CONNECTED)
1496                         return EPOLLIN | EPOLLRDNORM;
1497         }
1498
1499         return 0;
1500 }
1501
1502 __poll_t iucv_sock_poll(struct file *file, struct socket *sock,
1503                             poll_table *wait)
1504 {
1505         struct sock *sk = sock->sk;
1506         __poll_t mask = 0;
1507
1508         sock_poll_wait(file, wait);
1509
1510         if (sk->sk_state == IUCV_LISTEN)
1511                 return iucv_accept_poll(sk);
1512
1513         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1514                 mask |= EPOLLERR |
1515                         (sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
1516
1517         if (sk->sk_shutdown & RCV_SHUTDOWN)
1518                 mask |= EPOLLRDHUP;
1519
1520         if (sk->sk_shutdown == SHUTDOWN_MASK)
1521                 mask |= EPOLLHUP;
1522
1523         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1524             (sk->sk_shutdown & RCV_SHUTDOWN))
1525                 mask |= EPOLLIN | EPOLLRDNORM;
1526
1527         if (sk->sk_state == IUCV_CLOSED)
1528                 mask |= EPOLLHUP;
1529
1530         if (sk->sk_state == IUCV_DISCONN)
1531                 mask |= EPOLLIN;
1532
1533         if (sock_writeable(sk) && iucv_below_msglim(sk))
1534                 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
1535         else
1536                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1537
1538         return mask;
1539 }
1540
1541 static int iucv_sock_shutdown(struct socket *sock, int how)
1542 {
1543         struct sock *sk = sock->sk;
1544         struct iucv_sock *iucv = iucv_sk(sk);
1545         struct iucv_message txmsg;
1546         int err = 0;
1547
1548         how++;
1549
1550         if ((how & ~SHUTDOWN_MASK) || !how)
1551                 return -EINVAL;
1552
1553         lock_sock(sk);
1554         switch (sk->sk_state) {
1555         case IUCV_LISTEN:
1556         case IUCV_DISCONN:
1557         case IUCV_CLOSING:
1558         case IUCV_CLOSED:
1559                 err = -ENOTCONN;
1560                 goto fail;
1561         default:
1562                 break;
1563         }
1564
1565         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1566                 if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1567                         txmsg.class = 0;
1568                         txmsg.tag = 0;
1569                         err = pr_iucv->message_send(iucv->path, &txmsg,
1570                                 IUCV_IPRMDATA, 0, (void *) iprm_shutdown, 8);
1571                         if (err) {
1572                                 switch (err) {
1573                                 case 1:
1574                                         err = -ENOTCONN;
1575                                         break;
1576                                 case 2:
1577                                         err = -ECONNRESET;
1578                                         break;
1579                                 default:
1580                                         err = -ENOTCONN;
1581                                         break;
1582                                 }
1583                         }
1584                 } else
1585                         iucv_send_ctrl(sk, AF_IUCV_FLAG_SHT);
1586         }
1587
1588         sk->sk_shutdown |= how;
1589         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1590                 if ((iucv->transport == AF_IUCV_TRANS_IUCV) &&
1591                     iucv->path) {
1592                         err = pr_iucv->path_quiesce(iucv->path, NULL);
1593                         if (err)
1594                                 err = -ENOTCONN;
1595 /*                      skb_queue_purge(&sk->sk_receive_queue); */
1596                 }
1597                 skb_queue_purge(&sk->sk_receive_queue);
1598         }
1599
1600         /* Wake up anyone sleeping in poll */
1601         sk->sk_state_change(sk);
1602
1603 fail:
1604         release_sock(sk);
1605         return err;
1606 }
1607
1608 static int iucv_sock_release(struct socket *sock)
1609 {
1610         struct sock *sk = sock->sk;
1611         int err = 0;
1612
1613         if (!sk)
1614                 return 0;
1615
1616         iucv_sock_close(sk);
1617
1618         sock_orphan(sk);
1619         iucv_sock_kill(sk);
1620         return err;
1621 }
1622
1623 /* getsockopt and setsockopt */
1624 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1625                                 char __user *optval, unsigned int optlen)
1626 {
1627         struct sock *sk = sock->sk;
1628         struct iucv_sock *iucv = iucv_sk(sk);
1629         int val;
1630         int rc;
1631
1632         if (level != SOL_IUCV)
1633                 return -ENOPROTOOPT;
1634
1635         if (optlen < sizeof(int))
1636                 return -EINVAL;
1637
1638         if (get_user(val, (int __user *) optval))
1639                 return -EFAULT;
1640
1641         rc = 0;
1642
1643         lock_sock(sk);
1644         switch (optname) {
1645         case SO_IPRMDATA_MSG:
1646                 if (val)
1647                         iucv->flags |= IUCV_IPRMDATA;
1648                 else
1649                         iucv->flags &= ~IUCV_IPRMDATA;
1650                 break;
1651         case SO_MSGLIMIT:
1652                 switch (sk->sk_state) {
1653                 case IUCV_OPEN:
1654                 case IUCV_BOUND:
1655                         if (val < 1 || val > (u16)(~0))
1656                                 rc = -EINVAL;
1657                         else
1658                                 iucv->msglimit = val;
1659                         break;
1660                 default:
1661                         rc = -EINVAL;
1662                         break;
1663                 }
1664                 break;
1665         default:
1666                 rc = -ENOPROTOOPT;
1667                 break;
1668         }
1669         release_sock(sk);
1670
1671         return rc;
1672 }
1673
1674 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1675                                 char __user *optval, int __user *optlen)
1676 {
1677         struct sock *sk = sock->sk;
1678         struct iucv_sock *iucv = iucv_sk(sk);
1679         unsigned int val;
1680         int len;
1681
1682         if (level != SOL_IUCV)
1683                 return -ENOPROTOOPT;
1684
1685         if (get_user(len, optlen))
1686                 return -EFAULT;
1687
1688         if (len < 0)
1689                 return -EINVAL;
1690
1691         len = min_t(unsigned int, len, sizeof(int));
1692
1693         switch (optname) {
1694         case SO_IPRMDATA_MSG:
1695                 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1696                 break;
1697         case SO_MSGLIMIT:
1698                 lock_sock(sk);
1699                 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1700                                            : iucv->msglimit;    /* default */
1701                 release_sock(sk);
1702                 break;
1703         case SO_MSGSIZE:
1704                 if (sk->sk_state == IUCV_OPEN)
1705                         return -EBADFD;
1706                 val = (iucv->hs_dev) ? iucv->hs_dev->mtu -
1707                                 sizeof(struct af_iucv_trans_hdr) - ETH_HLEN :
1708                                 0x7fffffff;
1709                 break;
1710         default:
1711                 return -ENOPROTOOPT;
1712         }
1713
1714         if (put_user(len, optlen))
1715                 return -EFAULT;
1716         if (copy_to_user(optval, &val, len))
1717                 return -EFAULT;
1718
1719         return 0;
1720 }
1721
1722
1723 /* Callback wrappers - called from iucv base support */
1724 static int iucv_callback_connreq(struct iucv_path *path,
1725                                  u8 ipvmid[8], u8 ipuser[16])
1726 {
1727         unsigned char user_data[16];
1728         unsigned char nuser_data[16];
1729         unsigned char src_name[8];
1730         struct sock *sk, *nsk;
1731         struct iucv_sock *iucv, *niucv;
1732         int err;
1733
1734         memcpy(src_name, ipuser, 8);
1735         EBCASC(src_name, 8);
1736         /* Find out if this path belongs to af_iucv. */
1737         read_lock(&iucv_sk_list.lock);
1738         iucv = NULL;
1739         sk = NULL;
1740         sk_for_each(sk, &iucv_sk_list.head)
1741                 if (sk->sk_state == IUCV_LISTEN &&
1742                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1743                         /*
1744                          * Found a listening socket with
1745                          * src_name == ipuser[0-7].
1746                          */
1747                         iucv = iucv_sk(sk);
1748                         break;
1749                 }
1750         read_unlock(&iucv_sk_list.lock);
1751         if (!iucv)
1752                 /* No socket found, not one of our paths. */
1753                 return -EINVAL;
1754
1755         bh_lock_sock(sk);
1756
1757         /* Check if parent socket is listening */
1758         low_nmcpy(user_data, iucv->src_name);
1759         high_nmcpy(user_data, iucv->dst_name);
1760         ASCEBC(user_data, sizeof(user_data));
1761         if (sk->sk_state != IUCV_LISTEN) {
1762                 err = pr_iucv->path_sever(path, user_data);
1763                 iucv_path_free(path);
1764                 goto fail;
1765         }
1766
1767         /* Check for backlog size */
1768         if (sk_acceptq_is_full(sk)) {
1769                 err = pr_iucv->path_sever(path, user_data);
1770                 iucv_path_free(path);
1771                 goto fail;
1772         }
1773
1774         /* Create the new socket */
1775         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC, 0);
1776         if (!nsk) {
1777                 err = pr_iucv->path_sever(path, user_data);
1778                 iucv_path_free(path);
1779                 goto fail;
1780         }
1781
1782         niucv = iucv_sk(nsk);
1783         iucv_sock_init(nsk, sk);
1784
1785         /* Set the new iucv_sock */
1786         memcpy(niucv->dst_name, ipuser + 8, 8);
1787         EBCASC(niucv->dst_name, 8);
1788         memcpy(niucv->dst_user_id, ipvmid, 8);
1789         memcpy(niucv->src_name, iucv->src_name, 8);
1790         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1791         niucv->path = path;
1792
1793         /* Call iucv_accept */
1794         high_nmcpy(nuser_data, ipuser + 8);
1795         memcpy(nuser_data + 8, niucv->src_name, 8);
1796         ASCEBC(nuser_data + 8, 8);
1797
1798         /* set message limit for path based on msglimit of accepting socket */
1799         niucv->msglimit = iucv->msglimit;
1800         path->msglim = iucv->msglimit;
1801         err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1802         if (err) {
1803                 iucv_sever_path(nsk, 1);
1804                 iucv_sock_kill(nsk);
1805                 goto fail;
1806         }
1807
1808         iucv_accept_enqueue(sk, nsk);
1809
1810         /* Wake up accept */
1811         nsk->sk_state = IUCV_CONNECTED;
1812         sk->sk_data_ready(sk);
1813         err = 0;
1814 fail:
1815         bh_unlock_sock(sk);
1816         return 0;
1817 }
1818
1819 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1820 {
1821         struct sock *sk = path->private;
1822
1823         sk->sk_state = IUCV_CONNECTED;
1824         sk->sk_state_change(sk);
1825 }
1826
1827 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1828 {
1829         struct sock *sk = path->private;
1830         struct iucv_sock *iucv = iucv_sk(sk);
1831         struct sk_buff *skb;
1832         struct sock_msg_q *save_msg;
1833         int len;
1834
1835         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1836                 pr_iucv->message_reject(path, msg);
1837                 return;
1838         }
1839
1840         spin_lock(&iucv->message_q.lock);
1841
1842         if (!list_empty(&iucv->message_q.list) ||
1843             !skb_queue_empty(&iucv->backlog_skb_q))
1844                 goto save_message;
1845
1846         len = atomic_read(&sk->sk_rmem_alloc);
1847         len += SKB_TRUESIZE(iucv_msg_length(msg));
1848         if (len > sk->sk_rcvbuf)
1849                 goto save_message;
1850
1851         skb = alloc_iucv_recv_skb(iucv_msg_length(msg));
1852         if (!skb)
1853                 goto save_message;
1854
1855         iucv_process_message(sk, skb, path, msg);
1856         goto out_unlock;
1857
1858 save_message:
1859         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1860         if (!save_msg)
1861                 goto out_unlock;
1862         save_msg->path = path;
1863         save_msg->msg = *msg;
1864
1865         list_add_tail(&save_msg->list, &iucv->message_q.list);
1866
1867 out_unlock:
1868         spin_unlock(&iucv->message_q.lock);
1869 }
1870
1871 static void iucv_callback_txdone(struct iucv_path *path,
1872                                  struct iucv_message *msg)
1873 {
1874         struct sock *sk = path->private;
1875         struct sk_buff *this = NULL;
1876         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1877         struct sk_buff *list_skb = list->next;
1878         unsigned long flags;
1879
1880         bh_lock_sock(sk);
1881         if (!skb_queue_empty(list)) {
1882                 spin_lock_irqsave(&list->lock, flags);
1883
1884                 while (list_skb != (struct sk_buff *)list) {
1885                         if (msg->tag == IUCV_SKB_CB(list_skb)->tag) {
1886                                 this = list_skb;
1887                                 break;
1888                         }
1889                         list_skb = list_skb->next;
1890                 }
1891                 if (this)
1892                         __skb_unlink(this, list);
1893
1894                 spin_unlock_irqrestore(&list->lock, flags);
1895
1896                 if (this) {
1897                         kfree_skb(this);
1898                         /* wake up any process waiting for sending */
1899                         iucv_sock_wake_msglim(sk);
1900                 }
1901         }
1902
1903         if (sk->sk_state == IUCV_CLOSING) {
1904                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1905                         sk->sk_state = IUCV_CLOSED;
1906                         sk->sk_state_change(sk);
1907                 }
1908         }
1909         bh_unlock_sock(sk);
1910
1911 }
1912
1913 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1914 {
1915         struct sock *sk = path->private;
1916
1917         if (sk->sk_state == IUCV_CLOSED)
1918                 return;
1919
1920         bh_lock_sock(sk);
1921         iucv_sever_path(sk, 1);
1922         sk->sk_state = IUCV_DISCONN;
1923
1924         sk->sk_state_change(sk);
1925         bh_unlock_sock(sk);
1926 }
1927
1928 /* called if the other communication side shuts down its RECV direction;
1929  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1930  */
1931 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1932 {
1933         struct sock *sk = path->private;
1934
1935         bh_lock_sock(sk);
1936         if (sk->sk_state != IUCV_CLOSED) {
1937                 sk->sk_shutdown |= SEND_SHUTDOWN;
1938                 sk->sk_state_change(sk);
1939         }
1940         bh_unlock_sock(sk);
1941 }
1942
1943 /***************** HiperSockets transport callbacks ********************/
1944 static void afiucv_swap_src_dest(struct sk_buff *skb)
1945 {
1946         struct af_iucv_trans_hdr *trans_hdr =
1947                                 (struct af_iucv_trans_hdr *)skb->data;
1948         char tmpID[8];
1949         char tmpName[8];
1950
1951         ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1952         ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1953         ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1954         ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1955         memcpy(tmpID, trans_hdr->srcUserID, 8);
1956         memcpy(tmpName, trans_hdr->srcAppName, 8);
1957         memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1958         memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1959         memcpy(trans_hdr->destUserID, tmpID, 8);
1960         memcpy(trans_hdr->destAppName, tmpName, 8);
1961         skb_push(skb, ETH_HLEN);
1962         memset(skb->data, 0, ETH_HLEN);
1963 }
1964
1965 /**
1966  * afiucv_hs_callback_syn - react on received SYN
1967  **/
1968 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1969 {
1970         struct sock *nsk;
1971         struct iucv_sock *iucv, *niucv;
1972         struct af_iucv_trans_hdr *trans_hdr;
1973         int err;
1974
1975         iucv = iucv_sk(sk);
1976         trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
1977         if (!iucv) {
1978                 /* no sock - connection refused */
1979                 afiucv_swap_src_dest(skb);
1980                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1981                 err = dev_queue_xmit(skb);
1982                 goto out;
1983         }
1984
1985         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC, 0);
1986         bh_lock_sock(sk);
1987         if ((sk->sk_state != IUCV_LISTEN) ||
1988             sk_acceptq_is_full(sk) ||
1989             !nsk) {
1990                 /* error on server socket - connection refused */
1991                 afiucv_swap_src_dest(skb);
1992                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1993                 err = dev_queue_xmit(skb);
1994                 iucv_sock_kill(nsk);
1995                 bh_unlock_sock(sk);
1996                 goto out;
1997         }
1998
1999         niucv = iucv_sk(nsk);
2000         iucv_sock_init(nsk, sk);
2001         niucv->transport = AF_IUCV_TRANS_HIPER;
2002         niucv->msglimit = iucv->msglimit;
2003         if (!trans_hdr->window)
2004                 niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
2005         else
2006                 niucv->msglimit_peer = trans_hdr->window;
2007         memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
2008         memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
2009         memcpy(niucv->src_name, iucv->src_name, 8);
2010         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
2011         nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
2012         niucv->hs_dev = iucv->hs_dev;
2013         dev_hold(niucv->hs_dev);
2014         afiucv_swap_src_dest(skb);
2015         trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
2016         trans_hdr->window = niucv->msglimit;
2017         /* if receiver acks the xmit connection is established */
2018         err = dev_queue_xmit(skb);
2019         if (!err) {
2020                 iucv_accept_enqueue(sk, nsk);
2021                 nsk->sk_state = IUCV_CONNECTED;
2022                 sk->sk_data_ready(sk);
2023         } else
2024                 iucv_sock_kill(nsk);
2025         bh_unlock_sock(sk);
2026
2027 out:
2028         return NET_RX_SUCCESS;
2029 }
2030
2031 /**
2032  * afiucv_hs_callback_synack() - react on received SYN-ACK
2033  **/
2034 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
2035 {
2036         struct iucv_sock *iucv = iucv_sk(sk);
2037         struct af_iucv_trans_hdr *trans_hdr =
2038                                         (struct af_iucv_trans_hdr *)skb->data;
2039
2040         if (!iucv)
2041                 goto out;
2042         if (sk->sk_state != IUCV_BOUND)
2043                 goto out;
2044         bh_lock_sock(sk);
2045         iucv->msglimit_peer = trans_hdr->window;
2046         sk->sk_state = IUCV_CONNECTED;
2047         sk->sk_state_change(sk);
2048         bh_unlock_sock(sk);
2049 out:
2050         kfree_skb(skb);
2051         return NET_RX_SUCCESS;
2052 }
2053
2054 /**
2055  * afiucv_hs_callback_synfin() - react on received SYN_FIN
2056  **/
2057 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
2058 {
2059         struct iucv_sock *iucv = iucv_sk(sk);
2060
2061         if (!iucv)
2062                 goto out;
2063         if (sk->sk_state != IUCV_BOUND)
2064                 goto out;
2065         bh_lock_sock(sk);
2066         sk->sk_state = IUCV_DISCONN;
2067         sk->sk_state_change(sk);
2068         bh_unlock_sock(sk);
2069 out:
2070         kfree_skb(skb);
2071         return NET_RX_SUCCESS;
2072 }
2073
2074 /**
2075  * afiucv_hs_callback_fin() - react on received FIN
2076  **/
2077 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
2078 {
2079         struct iucv_sock *iucv = iucv_sk(sk);
2080
2081         /* other end of connection closed */
2082         if (!iucv)
2083                 goto out;
2084         bh_lock_sock(sk);
2085         if (sk->sk_state == IUCV_CONNECTED) {
2086                 sk->sk_state = IUCV_DISCONN;
2087                 sk->sk_state_change(sk);
2088         }
2089         bh_unlock_sock(sk);
2090 out:
2091         kfree_skb(skb);
2092         return NET_RX_SUCCESS;
2093 }
2094
2095 /**
2096  * afiucv_hs_callback_win() - react on received WIN
2097  **/
2098 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
2099 {
2100         struct iucv_sock *iucv = iucv_sk(sk);
2101         struct af_iucv_trans_hdr *trans_hdr =
2102                                         (struct af_iucv_trans_hdr *)skb->data;
2103
2104         if (!iucv)
2105                 return NET_RX_SUCCESS;
2106
2107         if (sk->sk_state != IUCV_CONNECTED)
2108                 return NET_RX_SUCCESS;
2109
2110         atomic_sub(trans_hdr->window, &iucv->msg_sent);
2111         iucv_sock_wake_msglim(sk);
2112         return NET_RX_SUCCESS;
2113 }
2114
2115 /**
2116  * afiucv_hs_callback_rx() - react on received data
2117  **/
2118 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
2119 {
2120         struct iucv_sock *iucv = iucv_sk(sk);
2121
2122         if (!iucv) {
2123                 kfree_skb(skb);
2124                 return NET_RX_SUCCESS;
2125         }
2126
2127         if (sk->sk_state != IUCV_CONNECTED) {
2128                 kfree_skb(skb);
2129                 return NET_RX_SUCCESS;
2130         }
2131
2132         if (sk->sk_shutdown & RCV_SHUTDOWN) {
2133                 kfree_skb(skb);
2134                 return NET_RX_SUCCESS;
2135         }
2136
2137         /* write stuff from iucv_msg to skb cb */
2138         skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2139         skb_reset_transport_header(skb);
2140         skb_reset_network_header(skb);
2141         IUCV_SKB_CB(skb)->offset = 0;
2142         if (sk_filter(sk, skb)) {
2143                 atomic_inc(&sk->sk_drops);      /* skb rejected by filter */
2144                 kfree_skb(skb);
2145                 return NET_RX_SUCCESS;
2146         }
2147
2148         spin_lock(&iucv->message_q.lock);
2149         if (skb_queue_empty(&iucv->backlog_skb_q)) {
2150                 if (__sock_queue_rcv_skb(sk, skb))
2151                         /* handle rcv queue full */
2152                         skb_queue_tail(&iucv->backlog_skb_q, skb);
2153         } else
2154                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2155         spin_unlock(&iucv->message_q.lock);
2156         return NET_RX_SUCCESS;
2157 }
2158
2159 /**
2160  * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2161  *                   transport
2162  *                   called from netif RX softirq
2163  **/
2164 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2165         struct packet_type *pt, struct net_device *orig_dev)
2166 {
2167         struct sock *sk;
2168         struct iucv_sock *iucv;
2169         struct af_iucv_trans_hdr *trans_hdr;
2170         int err = NET_RX_SUCCESS;
2171         char nullstring[8];
2172
2173         if (skb->len < (ETH_HLEN + sizeof(struct af_iucv_trans_hdr))) {
2174                 WARN_ONCE(1, "AF_IUCV too short skb, len=%d, min=%d",
2175                           (int)skb->len,
2176                           (int)(ETH_HLEN + sizeof(struct af_iucv_trans_hdr)));
2177                 kfree_skb(skb);
2178                 return NET_RX_SUCCESS;
2179         }
2180         if (skb_headlen(skb) < (ETH_HLEN + sizeof(struct af_iucv_trans_hdr)))
2181                 if (skb_linearize(skb)) {
2182                         WARN_ONCE(1, "AF_IUCV skb_linearize failed, len=%d",
2183                                   (int)skb->len);
2184                         kfree_skb(skb);
2185                         return NET_RX_SUCCESS;
2186                 }
2187         skb_pull(skb, ETH_HLEN);
2188         trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
2189         EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2190         EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2191         EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2192         EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2193         memset(nullstring, 0, sizeof(nullstring));
2194         iucv = NULL;
2195         sk = NULL;
2196         read_lock(&iucv_sk_list.lock);
2197         sk_for_each(sk, &iucv_sk_list.head) {
2198                 if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2199                         if ((!memcmp(&iucv_sk(sk)->src_name,
2200                                      trans_hdr->destAppName, 8)) &&
2201                             (!memcmp(&iucv_sk(sk)->src_user_id,
2202                                      trans_hdr->destUserID, 8)) &&
2203                             (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2204                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2205                                      nullstring, 8))) {
2206                                 iucv = iucv_sk(sk);
2207                                 break;
2208                         }
2209                 } else {
2210                         if ((!memcmp(&iucv_sk(sk)->src_name,
2211                                      trans_hdr->destAppName, 8)) &&
2212                             (!memcmp(&iucv_sk(sk)->src_user_id,
2213                                      trans_hdr->destUserID, 8)) &&
2214                             (!memcmp(&iucv_sk(sk)->dst_name,
2215                                      trans_hdr->srcAppName, 8)) &&
2216                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2217                                      trans_hdr->srcUserID, 8))) {
2218                                 iucv = iucv_sk(sk);
2219                                 break;
2220                         }
2221                 }
2222         }
2223         read_unlock(&iucv_sk_list.lock);
2224         if (!iucv)
2225                 sk = NULL;
2226
2227         /* no sock
2228         how should we send with no sock
2229         1) send without sock no send rc checking?
2230         2) introduce default sock to handle this cases
2231
2232          SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2233          data -> send FIN
2234          SYN|ACK, SYN|FIN, FIN -> no action? */
2235
2236         switch (trans_hdr->flags) {
2237         case AF_IUCV_FLAG_SYN:
2238                 /* connect request */
2239                 err = afiucv_hs_callback_syn(sk, skb);
2240                 break;
2241         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2242                 /* connect request confirmed */
2243                 err = afiucv_hs_callback_synack(sk, skb);
2244                 break;
2245         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2246                 /* connect request refused */
2247                 err = afiucv_hs_callback_synfin(sk, skb);
2248                 break;
2249         case (AF_IUCV_FLAG_FIN):
2250                 /* close request */
2251                 err = afiucv_hs_callback_fin(sk, skb);
2252                 break;
2253         case (AF_IUCV_FLAG_WIN):
2254                 err = afiucv_hs_callback_win(sk, skb);
2255                 if (skb->len == sizeof(struct af_iucv_trans_hdr)) {
2256                         kfree_skb(skb);
2257                         break;
2258                 }
2259                 /* fall through and receive non-zero length data */
2260         case (AF_IUCV_FLAG_SHT):
2261                 /* shutdown request */
2262                 /* fall through and receive zero length data */
2263         case 0:
2264                 /* plain data frame */
2265                 IUCV_SKB_CB(skb)->class = trans_hdr->iucv_hdr.class;
2266                 err = afiucv_hs_callback_rx(sk, skb);
2267                 break;
2268         default:
2269                 kfree_skb(skb);
2270         }
2271
2272         return err;
2273 }
2274
2275 /**
2276  * afiucv_hs_callback_txnotify() - handle send notifcations from HiperSockets
2277  *                                 transport
2278  **/
2279 static void afiucv_hs_callback_txnotify(struct sk_buff *skb,
2280                                         enum iucv_tx_notify n)
2281 {
2282         struct sock *isk = skb->sk;
2283         struct sock *sk = NULL;
2284         struct iucv_sock *iucv = NULL;
2285         struct sk_buff_head *list;
2286         struct sk_buff *list_skb;
2287         struct sk_buff *nskb;
2288         unsigned long flags;
2289
2290         read_lock_irqsave(&iucv_sk_list.lock, flags);
2291         sk_for_each(sk, &iucv_sk_list.head)
2292                 if (sk == isk) {
2293                         iucv = iucv_sk(sk);
2294                         break;
2295                 }
2296         read_unlock_irqrestore(&iucv_sk_list.lock, flags);
2297
2298         if (!iucv || sock_flag(sk, SOCK_ZAPPED))
2299                 return;
2300
2301         list = &iucv->send_skb_q;
2302         spin_lock_irqsave(&list->lock, flags);
2303         if (skb_queue_empty(list))
2304                 goto out_unlock;
2305         list_skb = list->next;
2306         nskb = list_skb->next;
2307         while (list_skb != (struct sk_buff *)list) {
2308                 if (skb_shinfo(list_skb) == skb_shinfo(skb)) {
2309                         switch (n) {
2310                         case TX_NOTIFY_OK:
2311                                 __skb_unlink(list_skb, list);
2312                                 kfree_skb(list_skb);
2313                                 iucv_sock_wake_msglim(sk);
2314                                 break;
2315                         case TX_NOTIFY_PENDING:
2316                                 atomic_inc(&iucv->pendings);
2317                                 break;
2318                         case TX_NOTIFY_DELAYED_OK:
2319                                 __skb_unlink(list_skb, list);
2320                                 atomic_dec(&iucv->pendings);
2321                                 if (atomic_read(&iucv->pendings) <= 0)
2322                                         iucv_sock_wake_msglim(sk);
2323                                 kfree_skb(list_skb);
2324                                 break;
2325                         case TX_NOTIFY_UNREACHABLE:
2326                         case TX_NOTIFY_DELAYED_UNREACHABLE:
2327                         case TX_NOTIFY_TPQFULL: /* not yet used */
2328                         case TX_NOTIFY_GENERALERROR:
2329                         case TX_NOTIFY_DELAYED_GENERALERROR:
2330                                 __skb_unlink(list_skb, list);
2331                                 kfree_skb(list_skb);
2332                                 if (sk->sk_state == IUCV_CONNECTED) {
2333                                         sk->sk_state = IUCV_DISCONN;
2334                                         sk->sk_state_change(sk);
2335                                 }
2336                                 break;
2337                         }
2338                         break;
2339                 }
2340                 list_skb = nskb;
2341                 nskb = nskb->next;
2342         }
2343 out_unlock:
2344         spin_unlock_irqrestore(&list->lock, flags);
2345
2346         if (sk->sk_state == IUCV_CLOSING) {
2347                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
2348                         sk->sk_state = IUCV_CLOSED;
2349                         sk->sk_state_change(sk);
2350                 }
2351         }
2352
2353 }
2354
2355 /*
2356  * afiucv_netdev_event: handle netdev notifier chain events
2357  */
2358 static int afiucv_netdev_event(struct notifier_block *this,
2359                                unsigned long event, void *ptr)
2360 {
2361         struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2362         struct sock *sk;
2363         struct iucv_sock *iucv;
2364
2365         switch (event) {
2366         case NETDEV_REBOOT:
2367         case NETDEV_GOING_DOWN:
2368                 sk_for_each(sk, &iucv_sk_list.head) {
2369                         iucv = iucv_sk(sk);
2370                         if ((iucv->hs_dev == event_dev) &&
2371                             (sk->sk_state == IUCV_CONNECTED)) {
2372                                 if (event == NETDEV_GOING_DOWN)
2373                                         iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
2374                                 sk->sk_state = IUCV_DISCONN;
2375                                 sk->sk_state_change(sk);
2376                         }
2377                 }
2378                 break;
2379         case NETDEV_DOWN:
2380         case NETDEV_UNREGISTER:
2381         default:
2382                 break;
2383         }
2384         return NOTIFY_DONE;
2385 }
2386
2387 static struct notifier_block afiucv_netdev_notifier = {
2388         .notifier_call = afiucv_netdev_event,
2389 };
2390
2391 static const struct proto_ops iucv_sock_ops = {
2392         .family         = PF_IUCV,
2393         .owner          = THIS_MODULE,
2394         .release        = iucv_sock_release,
2395         .bind           = iucv_sock_bind,
2396         .connect        = iucv_sock_connect,
2397         .listen         = iucv_sock_listen,
2398         .accept         = iucv_sock_accept,
2399         .getname        = iucv_sock_getname,
2400         .sendmsg        = iucv_sock_sendmsg,
2401         .recvmsg        = iucv_sock_recvmsg,
2402         .poll           = iucv_sock_poll,
2403         .ioctl          = sock_no_ioctl,
2404         .mmap           = sock_no_mmap,
2405         .socketpair     = sock_no_socketpair,
2406         .shutdown       = iucv_sock_shutdown,
2407         .setsockopt     = iucv_sock_setsockopt,
2408         .getsockopt     = iucv_sock_getsockopt,
2409 };
2410
2411 static const struct net_proto_family iucv_sock_family_ops = {
2412         .family = AF_IUCV,
2413         .owner  = THIS_MODULE,
2414         .create = iucv_sock_create,
2415 };
2416
2417 static struct packet_type iucv_packet_type = {
2418         .type = cpu_to_be16(ETH_P_AF_IUCV),
2419         .func = afiucv_hs_rcv,
2420 };
2421
2422 static int afiucv_iucv_init(void)
2423 {
2424         int err;
2425
2426         err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2427         if (err)
2428                 goto out;
2429         /* establish dummy device */
2430         af_iucv_driver.bus = pr_iucv->bus;
2431         err = driver_register(&af_iucv_driver);
2432         if (err)
2433                 goto out_iucv;
2434         af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2435         if (!af_iucv_dev) {
2436                 err = -ENOMEM;
2437                 goto out_driver;
2438         }
2439         dev_set_name(af_iucv_dev, "af_iucv");
2440         af_iucv_dev->bus = pr_iucv->bus;
2441         af_iucv_dev->parent = pr_iucv->root;
2442         af_iucv_dev->release = (void (*)(struct device *))kfree;
2443         af_iucv_dev->driver = &af_iucv_driver;
2444         err = device_register(af_iucv_dev);
2445         if (err)
2446                 goto out_iucv_dev;
2447         return 0;
2448
2449 out_iucv_dev:
2450         put_device(af_iucv_dev);
2451 out_driver:
2452         driver_unregister(&af_iucv_driver);
2453 out_iucv:
2454         pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2455 out:
2456         return err;
2457 }
2458
2459 static int __init afiucv_init(void)
2460 {
2461         int err;
2462
2463         if (MACHINE_IS_VM) {
2464                 cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2465                 if (unlikely(err)) {
2466                         WARN_ON(err);
2467                         err = -EPROTONOSUPPORT;
2468                         goto out;
2469                 }
2470
2471                 pr_iucv = try_then_request_module(symbol_get(iucv_if), "iucv");
2472                 if (!pr_iucv) {
2473                         printk(KERN_WARNING "iucv_if lookup failed\n");
2474                         memset(&iucv_userid, 0, sizeof(iucv_userid));
2475                 }
2476         } else {
2477                 memset(&iucv_userid, 0, sizeof(iucv_userid));
2478                 pr_iucv = NULL;
2479         }
2480
2481         err = proto_register(&iucv_proto, 0);
2482         if (err)
2483                 goto out;
2484         err = sock_register(&iucv_sock_family_ops);
2485         if (err)
2486                 goto out_proto;
2487
2488         if (pr_iucv) {
2489                 err = afiucv_iucv_init();
2490                 if (err)
2491                         goto out_sock;
2492         } else
2493                 register_netdevice_notifier(&afiucv_netdev_notifier);
2494         dev_add_pack(&iucv_packet_type);
2495         return 0;
2496
2497 out_sock:
2498         sock_unregister(PF_IUCV);
2499 out_proto:
2500         proto_unregister(&iucv_proto);
2501 out:
2502         if (pr_iucv)
2503                 symbol_put(iucv_if);
2504         return err;
2505 }
2506
2507 static void __exit afiucv_exit(void)
2508 {
2509         if (pr_iucv) {
2510                 device_unregister(af_iucv_dev);
2511                 driver_unregister(&af_iucv_driver);
2512                 pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2513                 symbol_put(iucv_if);
2514         } else
2515                 unregister_netdevice_notifier(&afiucv_netdev_notifier);
2516         dev_remove_pack(&iucv_packet_type);
2517         sock_unregister(PF_IUCV);
2518         proto_unregister(&iucv_proto);
2519 }
2520
2521 module_init(afiucv_init);
2522 module_exit(afiucv_exit);
2523
2524 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2525 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2526 MODULE_VERSION(VERSION);
2527 MODULE_LICENSE("GPL");
2528 MODULE_ALIAS_NETPROTO(PF_IUCV);