Linux-libre 4.11.5-gnu
[librecmc/linux-libre.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         int err = 0;
154
155 #ifdef CONFIG_PM_DEBUG
156         printk(KERN_WARNING "afiucv_pm_freeze\n");
157 #endif
158         read_lock(&iucv_sk_list.lock);
159         sk_for_each(sk, &iucv_sk_list.head) {
160                 iucv = iucv_sk(sk);
161                 switch (sk->sk_state) {
162                 case IUCV_DISCONN:
163                 case IUCV_CLOSING:
164                 case IUCV_CONNECTED:
165                         iucv_sever_path(sk, 0);
166                         break;
167                 case IUCV_OPEN:
168                 case IUCV_BOUND:
169                 case IUCV_LISTEN:
170                 case IUCV_CLOSED:
171                 default:
172                         break;
173                 }
174                 skb_queue_purge(&iucv->send_skb_q);
175                 skb_queue_purge(&iucv->backlog_skb_q);
176         }
177         read_unlock(&iucv_sk_list.lock);
178         return err;
179 }
180
181 /**
182  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
183  * @dev:        AFIUCV dummy device
184  *
185  * socket clean up after freeze
186  */
187 static int afiucv_pm_restore_thaw(struct device *dev)
188 {
189         struct sock *sk;
190
191 #ifdef CONFIG_PM_DEBUG
192         printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
193 #endif
194         read_lock(&iucv_sk_list.lock);
195         sk_for_each(sk, &iucv_sk_list.head) {
196                 switch (sk->sk_state) {
197                 case IUCV_CONNECTED:
198                         sk->sk_err = EPIPE;
199                         sk->sk_state = IUCV_DISCONN;
200                         sk->sk_state_change(sk);
201                         break;
202                 case IUCV_DISCONN:
203                 case IUCV_CLOSING:
204                 case IUCV_LISTEN:
205                 case IUCV_BOUND:
206                 case IUCV_OPEN:
207                 default:
208                         break;
209                 }
210         }
211         read_unlock(&iucv_sk_list.lock);
212         return 0;
213 }
214
215 static const struct dev_pm_ops afiucv_pm_ops = {
216         .prepare = afiucv_pm_prepare,
217         .complete = afiucv_pm_complete,
218         .freeze = afiucv_pm_freeze,
219         .thaw = afiucv_pm_restore_thaw,
220         .restore = afiucv_pm_restore_thaw,
221 };
222
223 static struct device_driver af_iucv_driver = {
224         .owner = THIS_MODULE,
225         .name = "afiucv",
226         .bus  = NULL,
227         .pm   = &afiucv_pm_ops,
228 };
229
230 /* dummy device used as trigger for PM functions */
231 static struct device *af_iucv_dev;
232
233 /**
234  * iucv_msg_length() - Returns the length of an iucv message.
235  * @msg:        Pointer to struct iucv_message, MUST NOT be NULL
236  *
237  * The function returns the length of the specified iucv message @msg of data
238  * stored in a buffer and of data stored in the parameter list (PRMDATA).
239  *
240  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
241  * data:
242  *      PRMDATA[0..6]   socket data (max 7 bytes);
243  *      PRMDATA[7]      socket data length value (len is 0xff - PRMDATA[7])
244  *
245  * The socket data length is computed by subtracting the socket data length
246  * value from 0xFF.
247  * If the socket data len is greater 7, then PRMDATA can be used for special
248  * notifications (see iucv_sock_shutdown); and further,
249  * if the socket data len is > 7, the function returns 8.
250  *
251  * Use this function to allocate socket buffers to store iucv message data.
252  */
253 static inline size_t iucv_msg_length(struct iucv_message *msg)
254 {
255         size_t datalen;
256
257         if (msg->flags & IUCV_IPRMDATA) {
258                 datalen = 0xff - msg->rmmsg[7];
259                 return (datalen < 8) ? datalen : 8;
260         }
261         return msg->length;
262 }
263
264 /**
265  * iucv_sock_in_state() - check for specific states
266  * @sk:         sock structure
267  * @state:      first iucv sk state
268  * @state:      second iucv sk state
269  *
270  * Returns true if the socket in either in the first or second state.
271  */
272 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
273 {
274         return (sk->sk_state == state || sk->sk_state == state2);
275 }
276
277 /**
278  * iucv_below_msglim() - function to check if messages can be sent
279  * @sk:         sock structure
280  *
281  * Returns true if the send queue length is lower than the message limit.
282  * Always returns true if the socket is not connected (no iucv path for
283  * checking the message limit).
284  */
285 static inline int iucv_below_msglim(struct sock *sk)
286 {
287         struct iucv_sock *iucv = iucv_sk(sk);
288
289         if (sk->sk_state != IUCV_CONNECTED)
290                 return 1;
291         if (iucv->transport == AF_IUCV_TRANS_IUCV)
292                 return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
293         else
294                 return ((atomic_read(&iucv->msg_sent) < iucv->msglimit_peer) &&
295                         (atomic_read(&iucv->pendings) <= 0));
296 }
297
298 /**
299  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
300  */
301 static void iucv_sock_wake_msglim(struct sock *sk)
302 {
303         struct socket_wq *wq;
304
305         rcu_read_lock();
306         wq = rcu_dereference(sk->sk_wq);
307         if (skwq_has_sleeper(wq))
308                 wake_up_interruptible_all(&wq->wait);
309         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
310         rcu_read_unlock();
311 }
312
313 /**
314  * afiucv_hs_send() - send a message through HiperSockets transport
315  */
316 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
317                    struct sk_buff *skb, u8 flags)
318 {
319         struct iucv_sock *iucv = iucv_sk(sock);
320         struct af_iucv_trans_hdr *phs_hdr;
321         struct sk_buff *nskb;
322         int err, confirm_recv = 0;
323
324         memset(skb->head, 0, ETH_HLEN);
325         phs_hdr = (struct af_iucv_trans_hdr *)skb_push(skb,
326                                         sizeof(struct af_iucv_trans_hdr));
327         skb_reset_mac_header(skb);
328         skb_reset_network_header(skb);
329         skb_push(skb, ETH_HLEN);
330         skb_reset_mac_header(skb);
331         memset(phs_hdr, 0, sizeof(struct af_iucv_trans_hdr));
332
333         phs_hdr->magic = ETH_P_AF_IUCV;
334         phs_hdr->version = 1;
335         phs_hdr->flags = flags;
336         if (flags == AF_IUCV_FLAG_SYN)
337                 phs_hdr->window = iucv->msglimit;
338         else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
339                 confirm_recv = atomic_read(&iucv->msg_recv);
340                 phs_hdr->window = confirm_recv;
341                 if (confirm_recv)
342                         phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
343         }
344         memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
345         memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
346         memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
347         memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
348         ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
349         ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
350         ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
351         ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
352         if (imsg)
353                 memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
354
355         skb->dev = iucv->hs_dev;
356         if (!skb->dev)
357                 return -ENODEV;
358         if (!(skb->dev->flags & IFF_UP) || !netif_carrier_ok(skb->dev))
359                 return -ENETDOWN;
360         if (skb->len > skb->dev->mtu) {
361                 if (sock->sk_type == SOCK_SEQPACKET)
362                         return -EMSGSIZE;
363                 else
364                         skb_trim(skb, skb->dev->mtu);
365         }
366         skb->protocol = ETH_P_AF_IUCV;
367         nskb = skb_clone(skb, GFP_ATOMIC);
368         if (!nskb)
369                 return -ENOMEM;
370         skb_queue_tail(&iucv->send_skb_q, nskb);
371         err = dev_queue_xmit(skb);
372         if (net_xmit_eval(err)) {
373                 skb_unlink(nskb, &iucv->send_skb_q);
374                 kfree_skb(nskb);
375         } else {
376                 atomic_sub(confirm_recv, &iucv->msg_recv);
377                 WARN_ON(atomic_read(&iucv->msg_recv) < 0);
378         }
379         return net_xmit_eval(err);
380 }
381
382 static struct sock *__iucv_get_sock_by_name(char *nm)
383 {
384         struct sock *sk;
385
386         sk_for_each(sk, &iucv_sk_list.head)
387                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
388                         return sk;
389
390         return NULL;
391 }
392
393 static void iucv_sock_destruct(struct sock *sk)
394 {
395         skb_queue_purge(&sk->sk_receive_queue);
396         skb_queue_purge(&sk->sk_error_queue);
397
398         sk_mem_reclaim(sk);
399
400         if (!sock_flag(sk, SOCK_DEAD)) {
401                 pr_err("Attempt to release alive iucv socket %p\n", sk);
402                 return;
403         }
404
405         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
406         WARN_ON(atomic_read(&sk->sk_wmem_alloc));
407         WARN_ON(sk->sk_wmem_queued);
408         WARN_ON(sk->sk_forward_alloc);
409 }
410
411 /* Cleanup Listen */
412 static void iucv_sock_cleanup_listen(struct sock *parent)
413 {
414         struct sock *sk;
415
416         /* Close non-accepted connections */
417         while ((sk = iucv_accept_dequeue(parent, NULL))) {
418                 iucv_sock_close(sk);
419                 iucv_sock_kill(sk);
420         }
421
422         parent->sk_state = IUCV_CLOSED;
423 }
424
425 /* Kill socket (only if zapped and orphaned) */
426 static void iucv_sock_kill(struct sock *sk)
427 {
428         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
429                 return;
430
431         iucv_sock_unlink(&iucv_sk_list, sk);
432         sock_set_flag(sk, SOCK_DEAD);
433         sock_put(sk);
434 }
435
436 /* Terminate an IUCV path */
437 static void iucv_sever_path(struct sock *sk, int with_user_data)
438 {
439         unsigned char user_data[16];
440         struct iucv_sock *iucv = iucv_sk(sk);
441         struct iucv_path *path = iucv->path;
442
443         if (iucv->path) {
444                 iucv->path = NULL;
445                 if (with_user_data) {
446                         low_nmcpy(user_data, iucv->src_name);
447                         high_nmcpy(user_data, iucv->dst_name);
448                         ASCEBC(user_data, sizeof(user_data));
449                         pr_iucv->path_sever(path, user_data);
450                 } else
451                         pr_iucv->path_sever(path, NULL);
452                 iucv_path_free(path);
453         }
454 }
455
456 /* Send controlling flags through an IUCV socket for HIPER transport */
457 static int iucv_send_ctrl(struct sock *sk, u8 flags)
458 {
459         int err = 0;
460         int blen;
461         struct sk_buff *skb;
462         u8 shutdown = 0;
463
464         blen = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
465         if (sk->sk_shutdown & SEND_SHUTDOWN) {
466                 /* controlling flags should be sent anyway */
467                 shutdown = sk->sk_shutdown;
468                 sk->sk_shutdown &= RCV_SHUTDOWN;
469         }
470         skb = sock_alloc_send_skb(sk, blen, 1, &err);
471         if (skb) {
472                 skb_reserve(skb, blen);
473                 err = afiucv_hs_send(NULL, sk, skb, flags);
474         }
475         if (shutdown)
476                 sk->sk_shutdown = shutdown;
477         return err;
478 }
479
480 /* Close an IUCV socket */
481 static void iucv_sock_close(struct sock *sk)
482 {
483         struct iucv_sock *iucv = iucv_sk(sk);
484         unsigned long timeo;
485         int err = 0;
486
487         lock_sock(sk);
488
489         switch (sk->sk_state) {
490         case IUCV_LISTEN:
491                 iucv_sock_cleanup_listen(sk);
492                 break;
493
494         case IUCV_CONNECTED:
495                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
496                         err = iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
497                         sk->sk_state = IUCV_DISCONN;
498                         sk->sk_state_change(sk);
499                 }
500         case IUCV_DISCONN:   /* fall through */
501                 sk->sk_state = IUCV_CLOSING;
502                 sk->sk_state_change(sk);
503
504                 if (!err && !skb_queue_empty(&iucv->send_skb_q)) {
505                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
506                                 timeo = sk->sk_lingertime;
507                         else
508                                 timeo = IUCV_DISCONN_TIMEOUT;
509                         iucv_sock_wait(sk,
510                                         iucv_sock_in_state(sk, IUCV_CLOSED, 0),
511                                         timeo);
512                 }
513
514         case IUCV_CLOSING:   /* fall through */
515                 sk->sk_state = IUCV_CLOSED;
516                 sk->sk_state_change(sk);
517
518                 sk->sk_err = ECONNRESET;
519                 sk->sk_state_change(sk);
520
521                 skb_queue_purge(&iucv->send_skb_q);
522                 skb_queue_purge(&iucv->backlog_skb_q);
523
524         default:   /* fall through */
525                 iucv_sever_path(sk, 1);
526         }
527
528         if (iucv->hs_dev) {
529                 dev_put(iucv->hs_dev);
530                 iucv->hs_dev = NULL;
531                 sk->sk_bound_dev_if = 0;
532         }
533
534         /* mark socket for deletion by iucv_sock_kill() */
535         sock_set_flag(sk, SOCK_ZAPPED);
536
537         release_sock(sk);
538 }
539
540 static void iucv_sock_init(struct sock *sk, struct sock *parent)
541 {
542         if (parent) {
543                 sk->sk_type = parent->sk_type;
544                 security_sk_clone(parent, sk);
545         }
546 }
547
548 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio, int kern)
549 {
550         struct sock *sk;
551         struct iucv_sock *iucv;
552
553         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto, kern);
554         if (!sk)
555                 return NULL;
556         iucv = iucv_sk(sk);
557
558         sock_init_data(sock, sk);
559         INIT_LIST_HEAD(&iucv->accept_q);
560         spin_lock_init(&iucv->accept_q_lock);
561         skb_queue_head_init(&iucv->send_skb_q);
562         INIT_LIST_HEAD(&iucv->message_q.list);
563         spin_lock_init(&iucv->message_q.lock);
564         skb_queue_head_init(&iucv->backlog_skb_q);
565         iucv->send_tag = 0;
566         atomic_set(&iucv->pendings, 0);
567         iucv->flags = 0;
568         iucv->msglimit = 0;
569         atomic_set(&iucv->msg_sent, 0);
570         atomic_set(&iucv->msg_recv, 0);
571         iucv->path = NULL;
572         iucv->sk_txnotify = afiucv_hs_callback_txnotify;
573         memset(&iucv->src_user_id , 0, 32);
574         if (pr_iucv)
575                 iucv->transport = AF_IUCV_TRANS_IUCV;
576         else
577                 iucv->transport = AF_IUCV_TRANS_HIPER;
578
579         sk->sk_destruct = iucv_sock_destruct;
580         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
581         sk->sk_allocation = GFP_DMA;
582
583         sock_reset_flag(sk, SOCK_ZAPPED);
584
585         sk->sk_protocol = proto;
586         sk->sk_state    = IUCV_OPEN;
587
588         iucv_sock_link(&iucv_sk_list, sk);
589         return sk;
590 }
591
592 /* Create an IUCV socket */
593 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
594                             int kern)
595 {
596         struct sock *sk;
597
598         if (protocol && protocol != PF_IUCV)
599                 return -EPROTONOSUPPORT;
600
601         sock->state = SS_UNCONNECTED;
602
603         switch (sock->type) {
604         case SOCK_STREAM:
605                 sock->ops = &iucv_sock_ops;
606                 break;
607         case SOCK_SEQPACKET:
608                 /* currently, proto ops can handle both sk types */
609                 sock->ops = &iucv_sock_ops;
610                 break;
611         default:
612                 return -ESOCKTNOSUPPORT;
613         }
614
615         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL, kern);
616         if (!sk)
617                 return -ENOMEM;
618
619         iucv_sock_init(sk, NULL);
620
621         return 0;
622 }
623
624 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
625 {
626         write_lock_bh(&l->lock);
627         sk_add_node(sk, &l->head);
628         write_unlock_bh(&l->lock);
629 }
630
631 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
632 {
633         write_lock_bh(&l->lock);
634         sk_del_node_init(sk);
635         write_unlock_bh(&l->lock);
636 }
637
638 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
639 {
640         unsigned long flags;
641         struct iucv_sock *par = iucv_sk(parent);
642
643         sock_hold(sk);
644         spin_lock_irqsave(&par->accept_q_lock, flags);
645         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
646         spin_unlock_irqrestore(&par->accept_q_lock, flags);
647         iucv_sk(sk)->parent = parent;
648         sk_acceptq_added(parent);
649 }
650
651 void iucv_accept_unlink(struct sock *sk)
652 {
653         unsigned long flags;
654         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
655
656         spin_lock_irqsave(&par->accept_q_lock, flags);
657         list_del_init(&iucv_sk(sk)->accept_q);
658         spin_unlock_irqrestore(&par->accept_q_lock, flags);
659         sk_acceptq_removed(iucv_sk(sk)->parent);
660         iucv_sk(sk)->parent = NULL;
661         sock_put(sk);
662 }
663
664 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
665 {
666         struct iucv_sock *isk, *n;
667         struct sock *sk;
668
669         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
670                 sk = (struct sock *) isk;
671                 lock_sock(sk);
672
673                 if (sk->sk_state == IUCV_CLOSED) {
674                         iucv_accept_unlink(sk);
675                         release_sock(sk);
676                         continue;
677                 }
678
679                 if (sk->sk_state == IUCV_CONNECTED ||
680                     sk->sk_state == IUCV_DISCONN ||
681                     !newsock) {
682                         iucv_accept_unlink(sk);
683                         if (newsock)
684                                 sock_graft(sk, newsock);
685
686                         release_sock(sk);
687                         return sk;
688                 }
689
690                 release_sock(sk);
691         }
692         return NULL;
693 }
694
695 static void __iucv_auto_name(struct iucv_sock *iucv)
696 {
697         char name[12];
698
699         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
700         while (__iucv_get_sock_by_name(name)) {
701                 sprintf(name, "%08x",
702                         atomic_inc_return(&iucv_sk_list.autobind_name));
703         }
704         memcpy(iucv->src_name, name, 8);
705 }
706
707 /* Bind an unbound socket */
708 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
709                           int addr_len)
710 {
711         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
712         struct sock *sk = sock->sk;
713         struct iucv_sock *iucv;
714         int err = 0;
715         struct net_device *dev;
716         char uid[9];
717
718         /* Verify the input sockaddr */
719         if (!addr || addr->sa_family != AF_IUCV)
720                 return -EINVAL;
721
722         if (addr_len < sizeof(struct sockaddr_iucv))
723                 return -EINVAL;
724
725         lock_sock(sk);
726         if (sk->sk_state != IUCV_OPEN) {
727                 err = -EBADFD;
728                 goto done;
729         }
730
731         write_lock_bh(&iucv_sk_list.lock);
732
733         iucv = iucv_sk(sk);
734         if (__iucv_get_sock_by_name(sa->siucv_name)) {
735                 err = -EADDRINUSE;
736                 goto done_unlock;
737         }
738         if (iucv->path)
739                 goto done_unlock;
740
741         /* Bind the socket */
742         if (pr_iucv)
743                 if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
744                         goto vm_bind; /* VM IUCV transport */
745
746         /* try hiper transport */
747         memcpy(uid, sa->siucv_user_id, sizeof(uid));
748         ASCEBC(uid, 8);
749         rcu_read_lock();
750         for_each_netdev_rcu(&init_net, dev) {
751                 if (!memcmp(dev->perm_addr, uid, 8)) {
752                         memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
753                         /* Check for unitialized siucv_name */
754                         if (strncmp(sa->siucv_name, "        ", 8) == 0)
755                                 __iucv_auto_name(iucv);
756                         else
757                                 memcpy(iucv->src_name, sa->siucv_name, 8);
758                         sk->sk_bound_dev_if = dev->ifindex;
759                         iucv->hs_dev = dev;
760                         dev_hold(dev);
761                         sk->sk_state = IUCV_BOUND;
762                         iucv->transport = AF_IUCV_TRANS_HIPER;
763                         if (!iucv->msglimit)
764                                 iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
765                         rcu_read_unlock();
766                         goto done_unlock;
767                 }
768         }
769         rcu_read_unlock();
770 vm_bind:
771         if (pr_iucv) {
772                 /* use local userid for backward compat */
773                 memcpy(iucv->src_name, sa->siucv_name, 8);
774                 memcpy(iucv->src_user_id, iucv_userid, 8);
775                 sk->sk_state = IUCV_BOUND;
776                 iucv->transport = AF_IUCV_TRANS_IUCV;
777                 if (!iucv->msglimit)
778                         iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
779                 goto done_unlock;
780         }
781         /* found no dev to bind */
782         err = -ENODEV;
783 done_unlock:
784         /* Release the socket list lock */
785         write_unlock_bh(&iucv_sk_list.lock);
786 done:
787         release_sock(sk);
788         return err;
789 }
790
791 /* Automatically bind an unbound socket */
792 static int iucv_sock_autobind(struct sock *sk)
793 {
794         struct iucv_sock *iucv = iucv_sk(sk);
795         int err = 0;
796
797         if (unlikely(!pr_iucv))
798                 return -EPROTO;
799
800         memcpy(iucv->src_user_id, iucv_userid, 8);
801
802         write_lock_bh(&iucv_sk_list.lock);
803         __iucv_auto_name(iucv);
804         write_unlock_bh(&iucv_sk_list.lock);
805
806         if (!iucv->msglimit)
807                 iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
808
809         return err;
810 }
811
812 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
813 {
814         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
815         struct sock *sk = sock->sk;
816         struct iucv_sock *iucv = iucv_sk(sk);
817         unsigned char user_data[16];
818         int err;
819
820         high_nmcpy(user_data, sa->siucv_name);
821         low_nmcpy(user_data, iucv->src_name);
822         ASCEBC(user_data, sizeof(user_data));
823
824         /* Create path. */
825         iucv->path = iucv_path_alloc(iucv->msglimit,
826                                      IUCV_IPRMDATA, GFP_KERNEL);
827         if (!iucv->path) {
828                 err = -ENOMEM;
829                 goto done;
830         }
831         err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
832                                     sa->siucv_user_id, NULL, user_data,
833                                     sk);
834         if (err) {
835                 iucv_path_free(iucv->path);
836                 iucv->path = NULL;
837                 switch (err) {
838                 case 0x0b:      /* Target communicator is not logged on */
839                         err = -ENETUNREACH;
840                         break;
841                 case 0x0d:      /* Max connections for this guest exceeded */
842                 case 0x0e:      /* Max connections for target guest exceeded */
843                         err = -EAGAIN;
844                         break;
845                 case 0x0f:      /* Missing IUCV authorization */
846                         err = -EACCES;
847                         break;
848                 default:
849                         err = -ECONNREFUSED;
850                         break;
851                 }
852         }
853 done:
854         return err;
855 }
856
857 /* Connect an unconnected socket */
858 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
859                              int alen, int flags)
860 {
861         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
862         struct sock *sk = sock->sk;
863         struct iucv_sock *iucv = iucv_sk(sk);
864         int err;
865
866         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
867                 return -EINVAL;
868
869         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
870                 return -EBADFD;
871
872         if (sk->sk_state == IUCV_OPEN &&
873             iucv->transport == AF_IUCV_TRANS_HIPER)
874                 return -EBADFD; /* explicit bind required */
875
876         if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
877                 return -EINVAL;
878
879         if (sk->sk_state == IUCV_OPEN) {
880                 err = iucv_sock_autobind(sk);
881                 if (unlikely(err))
882                         return err;
883         }
884
885         lock_sock(sk);
886
887         /* Set the destination information */
888         memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
889         memcpy(iucv->dst_name, sa->siucv_name, 8);
890
891         if (iucv->transport == AF_IUCV_TRANS_HIPER)
892                 err = iucv_send_ctrl(sock->sk, AF_IUCV_FLAG_SYN);
893         else
894                 err = afiucv_path_connect(sock, addr);
895         if (err)
896                 goto done;
897
898         if (sk->sk_state != IUCV_CONNECTED)
899                 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
900                                                             IUCV_DISCONN),
901                                      sock_sndtimeo(sk, flags & O_NONBLOCK));
902
903         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
904                 err = -ECONNREFUSED;
905
906         if (err && iucv->transport == AF_IUCV_TRANS_IUCV)
907                 iucv_sever_path(sk, 0);
908
909 done:
910         release_sock(sk);
911         return err;
912 }
913
914 /* Move a socket into listening state. */
915 static int iucv_sock_listen(struct socket *sock, int backlog)
916 {
917         struct sock *sk = sock->sk;
918         int err;
919
920         lock_sock(sk);
921
922         err = -EINVAL;
923         if (sk->sk_state != IUCV_BOUND)
924                 goto done;
925
926         if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
927                 goto done;
928
929         sk->sk_max_ack_backlog = backlog;
930         sk->sk_ack_backlog = 0;
931         sk->sk_state = IUCV_LISTEN;
932         err = 0;
933
934 done:
935         release_sock(sk);
936         return err;
937 }
938
939 /* Accept a pending connection */
940 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
941                             int flags, bool kern)
942 {
943         DECLARE_WAITQUEUE(wait, current);
944         struct sock *sk = sock->sk, *nsk;
945         long timeo;
946         int err = 0;
947
948         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
949
950         if (sk->sk_state != IUCV_LISTEN) {
951                 err = -EBADFD;
952                 goto done;
953         }
954
955         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
956
957         /* Wait for an incoming connection */
958         add_wait_queue_exclusive(sk_sleep(sk), &wait);
959         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
960                 set_current_state(TASK_INTERRUPTIBLE);
961                 if (!timeo) {
962                         err = -EAGAIN;
963                         break;
964                 }
965
966                 release_sock(sk);
967                 timeo = schedule_timeout(timeo);
968                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
969
970                 if (sk->sk_state != IUCV_LISTEN) {
971                         err = -EBADFD;
972                         break;
973                 }
974
975                 if (signal_pending(current)) {
976                         err = sock_intr_errno(timeo);
977                         break;
978                 }
979         }
980
981         set_current_state(TASK_RUNNING);
982         remove_wait_queue(sk_sleep(sk), &wait);
983
984         if (err)
985                 goto done;
986
987         newsock->state = SS_CONNECTED;
988
989 done:
990         release_sock(sk);
991         return err;
992 }
993
994 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
995                              int *len, int peer)
996 {
997         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
998         struct sock *sk = sock->sk;
999         struct iucv_sock *iucv = iucv_sk(sk);
1000
1001         addr->sa_family = AF_IUCV;
1002         *len = sizeof(struct sockaddr_iucv);
1003
1004         if (peer) {
1005                 memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
1006                 memcpy(siucv->siucv_name, iucv->dst_name, 8);
1007         } else {
1008                 memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
1009                 memcpy(siucv->siucv_name, iucv->src_name, 8);
1010         }
1011         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
1012         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
1013         memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
1014
1015         return 0;
1016 }
1017
1018 /**
1019  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
1020  * @path:       IUCV path
1021  * @msg:        Pointer to a struct iucv_message
1022  * @skb:        The socket data to send, skb->len MUST BE <= 7
1023  *
1024  * Send the socket data in the parameter list in the iucv message
1025  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
1026  * list and the socket data len at index 7 (last byte).
1027  * See also iucv_msg_length().
1028  *
1029  * Returns the error code from the iucv_message_send() call.
1030  */
1031 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
1032                           struct sk_buff *skb)
1033 {
1034         u8 prmdata[8];
1035
1036         memcpy(prmdata, (void *) skb->data, skb->len);
1037         prmdata[7] = 0xff - (u8) skb->len;
1038         return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
1039                                  (void *) prmdata, 8);
1040 }
1041
1042 static int iucv_sock_sendmsg(struct socket *sock, struct msghdr *msg,
1043                              size_t len)
1044 {
1045         struct sock *sk = sock->sk;
1046         struct iucv_sock *iucv = iucv_sk(sk);
1047         size_t headroom = 0;
1048         size_t linear;
1049         struct sk_buff *skb;
1050         struct iucv_message txmsg = {0};
1051         struct cmsghdr *cmsg;
1052         int cmsg_done;
1053         long timeo;
1054         char user_id[9];
1055         char appl_id[9];
1056         int err;
1057         int noblock = msg->msg_flags & MSG_DONTWAIT;
1058
1059         err = sock_error(sk);
1060         if (err)
1061                 return err;
1062
1063         if (msg->msg_flags & MSG_OOB)
1064                 return -EOPNOTSUPP;
1065
1066         /* SOCK_SEQPACKET: we do not support segmented records */
1067         if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
1068                 return -EOPNOTSUPP;
1069
1070         lock_sock(sk);
1071
1072         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1073                 err = -EPIPE;
1074                 goto out;
1075         }
1076
1077         /* Return if the socket is not in connected state */
1078         if (sk->sk_state != IUCV_CONNECTED) {
1079                 err = -ENOTCONN;
1080                 goto out;
1081         }
1082
1083         /* initialize defaults */
1084         cmsg_done   = 0;        /* check for duplicate headers */
1085         txmsg.class = 0;
1086
1087         /* iterate over control messages */
1088         for_each_cmsghdr(cmsg, msg) {
1089                 if (!CMSG_OK(msg, cmsg)) {
1090                         err = -EINVAL;
1091                         goto out;
1092                 }
1093
1094                 if (cmsg->cmsg_level != SOL_IUCV)
1095                         continue;
1096
1097                 if (cmsg->cmsg_type & cmsg_done) {
1098                         err = -EINVAL;
1099                         goto out;
1100                 }
1101                 cmsg_done |= cmsg->cmsg_type;
1102
1103                 switch (cmsg->cmsg_type) {
1104                 case SCM_IUCV_TRGCLS:
1105                         if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
1106                                 err = -EINVAL;
1107                                 goto out;
1108                         }
1109
1110                         /* set iucv message target class */
1111                         memcpy(&txmsg.class,
1112                                 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
1113
1114                         break;
1115
1116                 default:
1117                         err = -EINVAL;
1118                         goto out;
1119                 }
1120         }
1121
1122         /* allocate one skb for each iucv message:
1123          * this is fine for SOCK_SEQPACKET (unless we want to support
1124          * segmented records using the MSG_EOR flag), but
1125          * for SOCK_STREAM we might want to improve it in future */
1126         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1127                 headroom = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
1128                 linear = len;
1129         } else {
1130                 if (len < PAGE_SIZE) {
1131                         linear = len;
1132                 } else {
1133                         /* In nonlinear "classic" iucv skb,
1134                          * reserve space for iucv_array
1135                          */
1136                         headroom = sizeof(struct iucv_array) *
1137                                    (MAX_SKB_FRAGS + 1);
1138                         linear = PAGE_SIZE - headroom;
1139                 }
1140         }
1141         skb = sock_alloc_send_pskb(sk, headroom + linear, len - linear,
1142                                    noblock, &err, 0);
1143         if (!skb)
1144                 goto out;
1145         if (headroom)
1146                 skb_reserve(skb, headroom);
1147         skb_put(skb, linear);
1148         skb->len = len;
1149         skb->data_len = len - linear;
1150         err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, len);
1151         if (err)
1152                 goto fail;
1153
1154         /* wait if outstanding messages for iucv path has reached */
1155         timeo = sock_sndtimeo(sk, noblock);
1156         err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1157         if (err)
1158                 goto fail;
1159
1160         /* return -ECONNRESET if the socket is no longer connected */
1161         if (sk->sk_state != IUCV_CONNECTED) {
1162                 err = -ECONNRESET;
1163                 goto fail;
1164         }
1165
1166         /* increment and save iucv message tag for msg_completion cbk */
1167         txmsg.tag = iucv->send_tag++;
1168         IUCV_SKB_CB(skb)->tag = txmsg.tag;
1169
1170         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1171                 atomic_inc(&iucv->msg_sent);
1172                 err = afiucv_hs_send(&txmsg, sk, skb, 0);
1173                 if (err) {
1174                         atomic_dec(&iucv->msg_sent);
1175                         goto fail;
1176                 }
1177         } else { /* Classic VM IUCV transport */
1178                 skb_queue_tail(&iucv->send_skb_q, skb);
1179
1180                 if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags) &&
1181                     skb->len <= 7) {
1182                         err = iucv_send_iprm(iucv->path, &txmsg, skb);
1183
1184                         /* on success: there is no message_complete callback */
1185                         /* for an IPRMDATA msg; remove skb from send queue   */
1186                         if (err == 0) {
1187                                 skb_unlink(skb, &iucv->send_skb_q);
1188                                 kfree_skb(skb);
1189                         }
1190
1191                         /* this error should never happen since the     */
1192                         /* IUCV_IPRMDATA path flag is set... sever path */
1193                         if (err == 0x15) {
1194                                 pr_iucv->path_sever(iucv->path, NULL);
1195                                 skb_unlink(skb, &iucv->send_skb_q);
1196                                 err = -EPIPE;
1197                                 goto fail;
1198                         }
1199                 } else if (skb_is_nonlinear(skb)) {
1200                         struct iucv_array *iba = (struct iucv_array *)skb->head;
1201                         int i;
1202
1203                         /* skip iucv_array lying in the headroom */
1204                         iba[0].address = (u32)(addr_t)skb->data;
1205                         iba[0].length = (u32)skb_headlen(skb);
1206                         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1207                                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1208
1209                                 iba[i + 1].address =
1210                                         (u32)(addr_t)skb_frag_address(frag);
1211                                 iba[i + 1].length = (u32)skb_frag_size(frag);
1212                         }
1213                         err = pr_iucv->message_send(iucv->path, &txmsg,
1214                                                     IUCV_IPBUFLST, 0,
1215                                                     (void *)iba, skb->len);
1216                 } else { /* non-IPRM Linear skb */
1217                         err = pr_iucv->message_send(iucv->path, &txmsg,
1218                                         0, 0, (void *)skb->data, skb->len);
1219                 }
1220                 if (err) {
1221                         if (err == 3) {
1222                                 user_id[8] = 0;
1223                                 memcpy(user_id, iucv->dst_user_id, 8);
1224                                 appl_id[8] = 0;
1225                                 memcpy(appl_id, iucv->dst_name, 8);
1226                                 pr_err(
1227                 "Application %s on z/VM guest %s exceeds message limit\n",
1228                                         appl_id, user_id);
1229                                 err = -EAGAIN;
1230                         } else {
1231                                 err = -EPIPE;
1232                         }
1233                         skb_unlink(skb, &iucv->send_skb_q);
1234                         goto fail;
1235                 }
1236         }
1237
1238         release_sock(sk);
1239         return len;
1240
1241 fail:
1242         kfree_skb(skb);
1243 out:
1244         release_sock(sk);
1245         return err;
1246 }
1247
1248 static struct sk_buff *alloc_iucv_recv_skb(unsigned long len)
1249 {
1250         size_t headroom, linear;
1251         struct sk_buff *skb;
1252         int err;
1253
1254         if (len < PAGE_SIZE) {
1255                 headroom = 0;
1256                 linear = len;
1257         } else {
1258                 headroom = sizeof(struct iucv_array) * (MAX_SKB_FRAGS + 1);
1259                 linear = PAGE_SIZE - headroom;
1260         }
1261         skb = alloc_skb_with_frags(headroom + linear, len - linear,
1262                                    0, &err, GFP_ATOMIC | GFP_DMA);
1263         WARN_ONCE(!skb,
1264                   "alloc of recv iucv skb len=%lu failed with errcode=%d\n",
1265                   len, err);
1266         if (skb) {
1267                 if (headroom)
1268                         skb_reserve(skb, headroom);
1269                 skb_put(skb, linear);
1270                 skb->len = len;
1271                 skb->data_len = len - linear;
1272         }
1273         return skb;
1274 }
1275
1276 /* iucv_process_message() - Receive a single outstanding IUCV message
1277  *
1278  * Locking: must be called with message_q.lock held
1279  */
1280 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1281                                  struct iucv_path *path,
1282                                  struct iucv_message *msg)
1283 {
1284         int rc;
1285         unsigned int len;
1286
1287         len = iucv_msg_length(msg);
1288
1289         /* store msg target class in the second 4 bytes of skb ctrl buffer */
1290         /* Note: the first 4 bytes are reserved for msg tag */
1291         IUCV_SKB_CB(skb)->class = msg->class;
1292
1293         /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1294         if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1295                 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1296                         skb->data = NULL;
1297                         skb->len = 0;
1298                 }
1299         } else {
1300                 if (skb_is_nonlinear(skb)) {
1301                         struct iucv_array *iba = (struct iucv_array *)skb->head;
1302                         int i;
1303
1304                         iba[0].address = (u32)(addr_t)skb->data;
1305                         iba[0].length = (u32)skb_headlen(skb);
1306                         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1307                                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1308
1309                                 iba[i + 1].address =
1310                                         (u32)(addr_t)skb_frag_address(frag);
1311                                 iba[i + 1].length = (u32)skb_frag_size(frag);
1312                         }
1313                         rc = pr_iucv->message_receive(path, msg,
1314                                               IUCV_IPBUFLST,
1315                                               (void *)iba, len, NULL);
1316                 } else {
1317                         rc = pr_iucv->message_receive(path, msg,
1318                                               msg->flags & IUCV_IPRMDATA,
1319                                               skb->data, len, NULL);
1320                 }
1321                 if (rc) {
1322                         kfree_skb(skb);
1323                         return;
1324                 }
1325                 WARN_ON_ONCE(skb->len != len);
1326         }
1327
1328         IUCV_SKB_CB(skb)->offset = 0;
1329         if (sk_filter(sk, skb)) {
1330                 atomic_inc(&sk->sk_drops);      /* skb rejected by filter */
1331                 kfree_skb(skb);
1332                 return;
1333         }
1334         if (__sock_queue_rcv_skb(sk, skb))      /* handle rcv queue full */
1335                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
1336 }
1337
1338 /* iucv_process_message_q() - Process outstanding IUCV messages
1339  *
1340  * Locking: must be called with message_q.lock held
1341  */
1342 static void iucv_process_message_q(struct sock *sk)
1343 {
1344         struct iucv_sock *iucv = iucv_sk(sk);
1345         struct sk_buff *skb;
1346         struct sock_msg_q *p, *n;
1347
1348         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1349                 skb = alloc_iucv_recv_skb(iucv_msg_length(&p->msg));
1350                 if (!skb)
1351                         break;
1352                 iucv_process_message(sk, skb, p->path, &p->msg);
1353                 list_del(&p->list);
1354                 kfree(p);
1355                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1356                         break;
1357         }
1358 }
1359
1360 static int iucv_sock_recvmsg(struct socket *sock, struct msghdr *msg,
1361                              size_t len, int flags)
1362 {
1363         int noblock = flags & MSG_DONTWAIT;
1364         struct sock *sk = sock->sk;
1365         struct iucv_sock *iucv = iucv_sk(sk);
1366         unsigned int copied, rlen;
1367         struct sk_buff *skb, *rskb, *cskb;
1368         int err = 0;
1369         u32 offset;
1370
1371         if ((sk->sk_state == IUCV_DISCONN) &&
1372             skb_queue_empty(&iucv->backlog_skb_q) &&
1373             skb_queue_empty(&sk->sk_receive_queue) &&
1374             list_empty(&iucv->message_q.list))
1375                 return 0;
1376
1377         if (flags & (MSG_OOB))
1378                 return -EOPNOTSUPP;
1379
1380         /* receive/dequeue next skb:
1381          * the function understands MSG_PEEK and, thus, does not dequeue skb */
1382         skb = skb_recv_datagram(sk, flags, noblock, &err);
1383         if (!skb) {
1384                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1385                         return 0;
1386                 return err;
1387         }
1388
1389         offset = IUCV_SKB_CB(skb)->offset;
1390         rlen   = skb->len - offset;             /* real length of skb */
1391         copied = min_t(unsigned int, rlen, len);
1392         if (!rlen)
1393                 sk->sk_shutdown = sk->sk_shutdown | RCV_SHUTDOWN;
1394
1395         cskb = skb;
1396         if (skb_copy_datagram_msg(cskb, offset, msg, copied)) {
1397                 if (!(flags & MSG_PEEK))
1398                         skb_queue_head(&sk->sk_receive_queue, skb);
1399                 return -EFAULT;
1400         }
1401
1402         /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1403         if (sk->sk_type == SOCK_SEQPACKET) {
1404                 if (copied < rlen)
1405                         msg->msg_flags |= MSG_TRUNC;
1406                 /* each iucv message contains a complete record */
1407                 msg->msg_flags |= MSG_EOR;
1408         }
1409
1410         /* create control message to store iucv msg target class:
1411          * get the trgcls from the control buffer of the skb due to
1412          * fragmentation of original iucv message. */
1413         err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1414                        sizeof(IUCV_SKB_CB(skb)->class),
1415                        (void *)&IUCV_SKB_CB(skb)->class);
1416         if (err) {
1417                 if (!(flags & MSG_PEEK))
1418                         skb_queue_head(&sk->sk_receive_queue, skb);
1419                 return err;
1420         }
1421
1422         /* Mark read part of skb as used */
1423         if (!(flags & MSG_PEEK)) {
1424
1425                 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1426                 if (sk->sk_type == SOCK_STREAM) {
1427                         if (copied < rlen) {
1428                                 IUCV_SKB_CB(skb)->offset = offset + copied;
1429                                 skb_queue_head(&sk->sk_receive_queue, skb);
1430                                 goto done;
1431                         }
1432                 }
1433
1434                 kfree_skb(skb);
1435                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1436                         atomic_inc(&iucv->msg_recv);
1437                         if (atomic_read(&iucv->msg_recv) > iucv->msglimit) {
1438                                 WARN_ON(1);
1439                                 iucv_sock_close(sk);
1440                                 return -EFAULT;
1441                         }
1442                 }
1443
1444                 /* Queue backlog skbs */
1445                 spin_lock_bh(&iucv->message_q.lock);
1446                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1447                 while (rskb) {
1448                         IUCV_SKB_CB(rskb)->offset = 0;
1449                         if (__sock_queue_rcv_skb(sk, rskb)) {
1450                                 /* handle rcv queue full */
1451                                 skb_queue_head(&iucv->backlog_skb_q,
1452                                                 rskb);
1453                                 break;
1454                         }
1455                         rskb = skb_dequeue(&iucv->backlog_skb_q);
1456                 }
1457                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1458                         if (!list_empty(&iucv->message_q.list))
1459                                 iucv_process_message_q(sk);
1460                         if (atomic_read(&iucv->msg_recv) >=
1461                                                         iucv->msglimit / 2) {
1462                                 err = iucv_send_ctrl(sk, AF_IUCV_FLAG_WIN);
1463                                 if (err) {
1464                                         sk->sk_state = IUCV_DISCONN;
1465                                         sk->sk_state_change(sk);
1466                                 }
1467                         }
1468                 }
1469                 spin_unlock_bh(&iucv->message_q.lock);
1470         }
1471
1472 done:
1473         /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1474         if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1475                 copied = rlen;
1476
1477         return copied;
1478 }
1479
1480 static inline unsigned int iucv_accept_poll(struct sock *parent)
1481 {
1482         struct iucv_sock *isk, *n;
1483         struct sock *sk;
1484
1485         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1486                 sk = (struct sock *) isk;
1487
1488                 if (sk->sk_state == IUCV_CONNECTED)
1489                         return POLLIN | POLLRDNORM;
1490         }
1491
1492         return 0;
1493 }
1494
1495 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
1496                             poll_table *wait)
1497 {
1498         struct sock *sk = sock->sk;
1499         unsigned int mask = 0;
1500
1501         sock_poll_wait(file, sk_sleep(sk), wait);
1502
1503         if (sk->sk_state == IUCV_LISTEN)
1504                 return iucv_accept_poll(sk);
1505
1506         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1507                 mask |= POLLERR |
1508                         (sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? POLLPRI : 0);
1509
1510         if (sk->sk_shutdown & RCV_SHUTDOWN)
1511                 mask |= POLLRDHUP;
1512
1513         if (sk->sk_shutdown == SHUTDOWN_MASK)
1514                 mask |= POLLHUP;
1515
1516         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1517             (sk->sk_shutdown & RCV_SHUTDOWN))
1518                 mask |= POLLIN | POLLRDNORM;
1519
1520         if (sk->sk_state == IUCV_CLOSED)
1521                 mask |= POLLHUP;
1522
1523         if (sk->sk_state == IUCV_DISCONN)
1524                 mask |= POLLIN;
1525
1526         if (sock_writeable(sk) && iucv_below_msglim(sk))
1527                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1528         else
1529                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1530
1531         return mask;
1532 }
1533
1534 static int iucv_sock_shutdown(struct socket *sock, int how)
1535 {
1536         struct sock *sk = sock->sk;
1537         struct iucv_sock *iucv = iucv_sk(sk);
1538         struct iucv_message txmsg;
1539         int err = 0;
1540
1541         how++;
1542
1543         if ((how & ~SHUTDOWN_MASK) || !how)
1544                 return -EINVAL;
1545
1546         lock_sock(sk);
1547         switch (sk->sk_state) {
1548         case IUCV_LISTEN:
1549         case IUCV_DISCONN:
1550         case IUCV_CLOSING:
1551         case IUCV_CLOSED:
1552                 err = -ENOTCONN;
1553                 goto fail;
1554         default:
1555                 break;
1556         }
1557
1558         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1559                 if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1560                         txmsg.class = 0;
1561                         txmsg.tag = 0;
1562                         err = pr_iucv->message_send(iucv->path, &txmsg,
1563                                 IUCV_IPRMDATA, 0, (void *) iprm_shutdown, 8);
1564                         if (err) {
1565                                 switch (err) {
1566                                 case 1:
1567                                         err = -ENOTCONN;
1568                                         break;
1569                                 case 2:
1570                                         err = -ECONNRESET;
1571                                         break;
1572                                 default:
1573                                         err = -ENOTCONN;
1574                                         break;
1575                                 }
1576                         }
1577                 } else
1578                         iucv_send_ctrl(sk, AF_IUCV_FLAG_SHT);
1579         }
1580
1581         sk->sk_shutdown |= how;
1582         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1583                 if ((iucv->transport == AF_IUCV_TRANS_IUCV) &&
1584                     iucv->path) {
1585                         err = pr_iucv->path_quiesce(iucv->path, NULL);
1586                         if (err)
1587                                 err = -ENOTCONN;
1588 /*                      skb_queue_purge(&sk->sk_receive_queue); */
1589                 }
1590                 skb_queue_purge(&sk->sk_receive_queue);
1591         }
1592
1593         /* Wake up anyone sleeping in poll */
1594         sk->sk_state_change(sk);
1595
1596 fail:
1597         release_sock(sk);
1598         return err;
1599 }
1600
1601 static int iucv_sock_release(struct socket *sock)
1602 {
1603         struct sock *sk = sock->sk;
1604         int err = 0;
1605
1606         if (!sk)
1607                 return 0;
1608
1609         iucv_sock_close(sk);
1610
1611         sock_orphan(sk);
1612         iucv_sock_kill(sk);
1613         return err;
1614 }
1615
1616 /* getsockopt and setsockopt */
1617 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1618                                 char __user *optval, unsigned int optlen)
1619 {
1620         struct sock *sk = sock->sk;
1621         struct iucv_sock *iucv = iucv_sk(sk);
1622         int val;
1623         int rc;
1624
1625         if (level != SOL_IUCV)
1626                 return -ENOPROTOOPT;
1627
1628         if (optlen < sizeof(int))
1629                 return -EINVAL;
1630
1631         if (get_user(val, (int __user *) optval))
1632                 return -EFAULT;
1633
1634         rc = 0;
1635
1636         lock_sock(sk);
1637         switch (optname) {
1638         case SO_IPRMDATA_MSG:
1639                 if (val)
1640                         iucv->flags |= IUCV_IPRMDATA;
1641                 else
1642                         iucv->flags &= ~IUCV_IPRMDATA;
1643                 break;
1644         case SO_MSGLIMIT:
1645                 switch (sk->sk_state) {
1646                 case IUCV_OPEN:
1647                 case IUCV_BOUND:
1648                         if (val < 1 || val > (u16)(~0))
1649                                 rc = -EINVAL;
1650                         else
1651                                 iucv->msglimit = val;
1652                         break;
1653                 default:
1654                         rc = -EINVAL;
1655                         break;
1656                 }
1657                 break;
1658         default:
1659                 rc = -ENOPROTOOPT;
1660                 break;
1661         }
1662         release_sock(sk);
1663
1664         return rc;
1665 }
1666
1667 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1668                                 char __user *optval, int __user *optlen)
1669 {
1670         struct sock *sk = sock->sk;
1671         struct iucv_sock *iucv = iucv_sk(sk);
1672         unsigned int val;
1673         int len;
1674
1675         if (level != SOL_IUCV)
1676                 return -ENOPROTOOPT;
1677
1678         if (get_user(len, optlen))
1679                 return -EFAULT;
1680
1681         if (len < 0)
1682                 return -EINVAL;
1683
1684         len = min_t(unsigned int, len, sizeof(int));
1685
1686         switch (optname) {
1687         case SO_IPRMDATA_MSG:
1688                 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1689                 break;
1690         case SO_MSGLIMIT:
1691                 lock_sock(sk);
1692                 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1693                                            : iucv->msglimit;    /* default */
1694                 release_sock(sk);
1695                 break;
1696         case SO_MSGSIZE:
1697                 if (sk->sk_state == IUCV_OPEN)
1698                         return -EBADFD;
1699                 val = (iucv->hs_dev) ? iucv->hs_dev->mtu -
1700                                 sizeof(struct af_iucv_trans_hdr) - ETH_HLEN :
1701                                 0x7fffffff;
1702                 break;
1703         default:
1704                 return -ENOPROTOOPT;
1705         }
1706
1707         if (put_user(len, optlen))
1708                 return -EFAULT;
1709         if (copy_to_user(optval, &val, len))
1710                 return -EFAULT;
1711
1712         return 0;
1713 }
1714
1715
1716 /* Callback wrappers - called from iucv base support */
1717 static int iucv_callback_connreq(struct iucv_path *path,
1718                                  u8 ipvmid[8], u8 ipuser[16])
1719 {
1720         unsigned char user_data[16];
1721         unsigned char nuser_data[16];
1722         unsigned char src_name[8];
1723         struct sock *sk, *nsk;
1724         struct iucv_sock *iucv, *niucv;
1725         int err;
1726
1727         memcpy(src_name, ipuser, 8);
1728         EBCASC(src_name, 8);
1729         /* Find out if this path belongs to af_iucv. */
1730         read_lock(&iucv_sk_list.lock);
1731         iucv = NULL;
1732         sk = NULL;
1733         sk_for_each(sk, &iucv_sk_list.head)
1734                 if (sk->sk_state == IUCV_LISTEN &&
1735                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1736                         /*
1737                          * Found a listening socket with
1738                          * src_name == ipuser[0-7].
1739                          */
1740                         iucv = iucv_sk(sk);
1741                         break;
1742                 }
1743         read_unlock(&iucv_sk_list.lock);
1744         if (!iucv)
1745                 /* No socket found, not one of our paths. */
1746                 return -EINVAL;
1747
1748         bh_lock_sock(sk);
1749
1750         /* Check if parent socket is listening */
1751         low_nmcpy(user_data, iucv->src_name);
1752         high_nmcpy(user_data, iucv->dst_name);
1753         ASCEBC(user_data, sizeof(user_data));
1754         if (sk->sk_state != IUCV_LISTEN) {
1755                 err = pr_iucv->path_sever(path, user_data);
1756                 iucv_path_free(path);
1757                 goto fail;
1758         }
1759
1760         /* Check for backlog size */
1761         if (sk_acceptq_is_full(sk)) {
1762                 err = pr_iucv->path_sever(path, user_data);
1763                 iucv_path_free(path);
1764                 goto fail;
1765         }
1766
1767         /* Create the new socket */
1768         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC, 0);
1769         if (!nsk) {
1770                 err = pr_iucv->path_sever(path, user_data);
1771                 iucv_path_free(path);
1772                 goto fail;
1773         }
1774
1775         niucv = iucv_sk(nsk);
1776         iucv_sock_init(nsk, sk);
1777
1778         /* Set the new iucv_sock */
1779         memcpy(niucv->dst_name, ipuser + 8, 8);
1780         EBCASC(niucv->dst_name, 8);
1781         memcpy(niucv->dst_user_id, ipvmid, 8);
1782         memcpy(niucv->src_name, iucv->src_name, 8);
1783         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1784         niucv->path = path;
1785
1786         /* Call iucv_accept */
1787         high_nmcpy(nuser_data, ipuser + 8);
1788         memcpy(nuser_data + 8, niucv->src_name, 8);
1789         ASCEBC(nuser_data + 8, 8);
1790
1791         /* set message limit for path based on msglimit of accepting socket */
1792         niucv->msglimit = iucv->msglimit;
1793         path->msglim = iucv->msglimit;
1794         err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1795         if (err) {
1796                 iucv_sever_path(nsk, 1);
1797                 iucv_sock_kill(nsk);
1798                 goto fail;
1799         }
1800
1801         iucv_accept_enqueue(sk, nsk);
1802
1803         /* Wake up accept */
1804         nsk->sk_state = IUCV_CONNECTED;
1805         sk->sk_data_ready(sk);
1806         err = 0;
1807 fail:
1808         bh_unlock_sock(sk);
1809         return 0;
1810 }
1811
1812 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1813 {
1814         struct sock *sk = path->private;
1815
1816         sk->sk_state = IUCV_CONNECTED;
1817         sk->sk_state_change(sk);
1818 }
1819
1820 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1821 {
1822         struct sock *sk = path->private;
1823         struct iucv_sock *iucv = iucv_sk(sk);
1824         struct sk_buff *skb;
1825         struct sock_msg_q *save_msg;
1826         int len;
1827
1828         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1829                 pr_iucv->message_reject(path, msg);
1830                 return;
1831         }
1832
1833         spin_lock(&iucv->message_q.lock);
1834
1835         if (!list_empty(&iucv->message_q.list) ||
1836             !skb_queue_empty(&iucv->backlog_skb_q))
1837                 goto save_message;
1838
1839         len = atomic_read(&sk->sk_rmem_alloc);
1840         len += SKB_TRUESIZE(iucv_msg_length(msg));
1841         if (len > sk->sk_rcvbuf)
1842                 goto save_message;
1843
1844         skb = alloc_iucv_recv_skb(iucv_msg_length(msg));
1845         if (!skb)
1846                 goto save_message;
1847
1848         iucv_process_message(sk, skb, path, msg);
1849         goto out_unlock;
1850
1851 save_message:
1852         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1853         if (!save_msg)
1854                 goto out_unlock;
1855         save_msg->path = path;
1856         save_msg->msg = *msg;
1857
1858         list_add_tail(&save_msg->list, &iucv->message_q.list);
1859
1860 out_unlock:
1861         spin_unlock(&iucv->message_q.lock);
1862 }
1863
1864 static void iucv_callback_txdone(struct iucv_path *path,
1865                                  struct iucv_message *msg)
1866 {
1867         struct sock *sk = path->private;
1868         struct sk_buff *this = NULL;
1869         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1870         struct sk_buff *list_skb = list->next;
1871         unsigned long flags;
1872
1873         bh_lock_sock(sk);
1874         if (!skb_queue_empty(list)) {
1875                 spin_lock_irqsave(&list->lock, flags);
1876
1877                 while (list_skb != (struct sk_buff *)list) {
1878                         if (msg->tag == IUCV_SKB_CB(list_skb)->tag) {
1879                                 this = list_skb;
1880                                 break;
1881                         }
1882                         list_skb = list_skb->next;
1883                 }
1884                 if (this)
1885                         __skb_unlink(this, list);
1886
1887                 spin_unlock_irqrestore(&list->lock, flags);
1888
1889                 if (this) {
1890                         kfree_skb(this);
1891                         /* wake up any process waiting for sending */
1892                         iucv_sock_wake_msglim(sk);
1893                 }
1894         }
1895
1896         if (sk->sk_state == IUCV_CLOSING) {
1897                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1898                         sk->sk_state = IUCV_CLOSED;
1899                         sk->sk_state_change(sk);
1900                 }
1901         }
1902         bh_unlock_sock(sk);
1903
1904 }
1905
1906 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1907 {
1908         struct sock *sk = path->private;
1909
1910         if (sk->sk_state == IUCV_CLOSED)
1911                 return;
1912
1913         bh_lock_sock(sk);
1914         iucv_sever_path(sk, 1);
1915         sk->sk_state = IUCV_DISCONN;
1916
1917         sk->sk_state_change(sk);
1918         bh_unlock_sock(sk);
1919 }
1920
1921 /* called if the other communication side shuts down its RECV direction;
1922  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1923  */
1924 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1925 {
1926         struct sock *sk = path->private;
1927
1928         bh_lock_sock(sk);
1929         if (sk->sk_state != IUCV_CLOSED) {
1930                 sk->sk_shutdown |= SEND_SHUTDOWN;
1931                 sk->sk_state_change(sk);
1932         }
1933         bh_unlock_sock(sk);
1934 }
1935
1936 /***************** HiperSockets transport callbacks ********************/
1937 static void afiucv_swap_src_dest(struct sk_buff *skb)
1938 {
1939         struct af_iucv_trans_hdr *trans_hdr =
1940                                 (struct af_iucv_trans_hdr *)skb->data;
1941         char tmpID[8];
1942         char tmpName[8];
1943
1944         ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1945         ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1946         ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1947         ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1948         memcpy(tmpID, trans_hdr->srcUserID, 8);
1949         memcpy(tmpName, trans_hdr->srcAppName, 8);
1950         memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1951         memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1952         memcpy(trans_hdr->destUserID, tmpID, 8);
1953         memcpy(trans_hdr->destAppName, tmpName, 8);
1954         skb_push(skb, ETH_HLEN);
1955         memset(skb->data, 0, ETH_HLEN);
1956 }
1957
1958 /**
1959  * afiucv_hs_callback_syn - react on received SYN
1960  **/
1961 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1962 {
1963         struct sock *nsk;
1964         struct iucv_sock *iucv, *niucv;
1965         struct af_iucv_trans_hdr *trans_hdr;
1966         int err;
1967
1968         iucv = iucv_sk(sk);
1969         trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
1970         if (!iucv) {
1971                 /* no sock - connection refused */
1972                 afiucv_swap_src_dest(skb);
1973                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1974                 err = dev_queue_xmit(skb);
1975                 goto out;
1976         }
1977
1978         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC, 0);
1979         bh_lock_sock(sk);
1980         if ((sk->sk_state != IUCV_LISTEN) ||
1981             sk_acceptq_is_full(sk) ||
1982             !nsk) {
1983                 /* error on server socket - connection refused */
1984                 afiucv_swap_src_dest(skb);
1985                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1986                 err = dev_queue_xmit(skb);
1987                 iucv_sock_kill(nsk);
1988                 bh_unlock_sock(sk);
1989                 goto out;
1990         }
1991
1992         niucv = iucv_sk(nsk);
1993         iucv_sock_init(nsk, sk);
1994         niucv->transport = AF_IUCV_TRANS_HIPER;
1995         niucv->msglimit = iucv->msglimit;
1996         if (!trans_hdr->window)
1997                 niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
1998         else
1999                 niucv->msglimit_peer = trans_hdr->window;
2000         memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
2001         memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
2002         memcpy(niucv->src_name, iucv->src_name, 8);
2003         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
2004         nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
2005         niucv->hs_dev = iucv->hs_dev;
2006         dev_hold(niucv->hs_dev);
2007         afiucv_swap_src_dest(skb);
2008         trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
2009         trans_hdr->window = niucv->msglimit;
2010         /* if receiver acks the xmit connection is established */
2011         err = dev_queue_xmit(skb);
2012         if (!err) {
2013                 iucv_accept_enqueue(sk, nsk);
2014                 nsk->sk_state = IUCV_CONNECTED;
2015                 sk->sk_data_ready(sk);
2016         } else
2017                 iucv_sock_kill(nsk);
2018         bh_unlock_sock(sk);
2019
2020 out:
2021         return NET_RX_SUCCESS;
2022 }
2023
2024 /**
2025  * afiucv_hs_callback_synack() - react on received SYN-ACK
2026  **/
2027 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
2028 {
2029         struct iucv_sock *iucv = iucv_sk(sk);
2030         struct af_iucv_trans_hdr *trans_hdr =
2031                                         (struct af_iucv_trans_hdr *)skb->data;
2032
2033         if (!iucv)
2034                 goto out;
2035         if (sk->sk_state != IUCV_BOUND)
2036                 goto out;
2037         bh_lock_sock(sk);
2038         iucv->msglimit_peer = trans_hdr->window;
2039         sk->sk_state = IUCV_CONNECTED;
2040         sk->sk_state_change(sk);
2041         bh_unlock_sock(sk);
2042 out:
2043         kfree_skb(skb);
2044         return NET_RX_SUCCESS;
2045 }
2046
2047 /**
2048  * afiucv_hs_callback_synfin() - react on received SYN_FIN
2049  **/
2050 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
2051 {
2052         struct iucv_sock *iucv = iucv_sk(sk);
2053
2054         if (!iucv)
2055                 goto out;
2056         if (sk->sk_state != IUCV_BOUND)
2057                 goto out;
2058         bh_lock_sock(sk);
2059         sk->sk_state = IUCV_DISCONN;
2060         sk->sk_state_change(sk);
2061         bh_unlock_sock(sk);
2062 out:
2063         kfree_skb(skb);
2064         return NET_RX_SUCCESS;
2065 }
2066
2067 /**
2068  * afiucv_hs_callback_fin() - react on received FIN
2069  **/
2070 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
2071 {
2072         struct iucv_sock *iucv = iucv_sk(sk);
2073
2074         /* other end of connection closed */
2075         if (!iucv)
2076                 goto out;
2077         bh_lock_sock(sk);
2078         if (sk->sk_state == IUCV_CONNECTED) {
2079                 sk->sk_state = IUCV_DISCONN;
2080                 sk->sk_state_change(sk);
2081         }
2082         bh_unlock_sock(sk);
2083 out:
2084         kfree_skb(skb);
2085         return NET_RX_SUCCESS;
2086 }
2087
2088 /**
2089  * afiucv_hs_callback_win() - react on received WIN
2090  **/
2091 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
2092 {
2093         struct iucv_sock *iucv = iucv_sk(sk);
2094         struct af_iucv_trans_hdr *trans_hdr =
2095                                         (struct af_iucv_trans_hdr *)skb->data;
2096
2097         if (!iucv)
2098                 return NET_RX_SUCCESS;
2099
2100         if (sk->sk_state != IUCV_CONNECTED)
2101                 return NET_RX_SUCCESS;
2102
2103         atomic_sub(trans_hdr->window, &iucv->msg_sent);
2104         iucv_sock_wake_msglim(sk);
2105         return NET_RX_SUCCESS;
2106 }
2107
2108 /**
2109  * afiucv_hs_callback_rx() - react on received data
2110  **/
2111 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
2112 {
2113         struct iucv_sock *iucv = iucv_sk(sk);
2114
2115         if (!iucv) {
2116                 kfree_skb(skb);
2117                 return NET_RX_SUCCESS;
2118         }
2119
2120         if (sk->sk_state != IUCV_CONNECTED) {
2121                 kfree_skb(skb);
2122                 return NET_RX_SUCCESS;
2123         }
2124
2125         if (sk->sk_shutdown & RCV_SHUTDOWN) {
2126                 kfree_skb(skb);
2127                 return NET_RX_SUCCESS;
2128         }
2129
2130         /* write stuff from iucv_msg to skb cb */
2131         skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2132         skb_reset_transport_header(skb);
2133         skb_reset_network_header(skb);
2134         IUCV_SKB_CB(skb)->offset = 0;
2135         if (sk_filter(sk, skb)) {
2136                 atomic_inc(&sk->sk_drops);      /* skb rejected by filter */
2137                 kfree_skb(skb);
2138                 return NET_RX_SUCCESS;
2139         }
2140
2141         spin_lock(&iucv->message_q.lock);
2142         if (skb_queue_empty(&iucv->backlog_skb_q)) {
2143                 if (__sock_queue_rcv_skb(sk, skb))
2144                         /* handle rcv queue full */
2145                         skb_queue_tail(&iucv->backlog_skb_q, skb);
2146         } else
2147                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2148         spin_unlock(&iucv->message_q.lock);
2149         return NET_RX_SUCCESS;
2150 }
2151
2152 /**
2153  * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2154  *                   transport
2155  *                   called from netif RX softirq
2156  **/
2157 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2158         struct packet_type *pt, struct net_device *orig_dev)
2159 {
2160         struct sock *sk;
2161         struct iucv_sock *iucv;
2162         struct af_iucv_trans_hdr *trans_hdr;
2163         char nullstring[8];
2164         int err = 0;
2165
2166         if (skb->len < (ETH_HLEN + sizeof(struct af_iucv_trans_hdr))) {
2167                 WARN_ONCE(1, "AF_IUCV too short skb, len=%d, min=%d",
2168                           (int)skb->len,
2169                           (int)(ETH_HLEN + sizeof(struct af_iucv_trans_hdr)));
2170                 kfree_skb(skb);
2171                 return NET_RX_SUCCESS;
2172         }
2173         if (skb_headlen(skb) < (ETH_HLEN + sizeof(struct af_iucv_trans_hdr)))
2174                 if (skb_linearize(skb)) {
2175                         WARN_ONCE(1, "AF_IUCV skb_linearize failed, len=%d",
2176                                   (int)skb->len);
2177                         kfree_skb(skb);
2178                         return NET_RX_SUCCESS;
2179                 }
2180         skb_pull(skb, ETH_HLEN);
2181         trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
2182         EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2183         EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2184         EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2185         EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2186         memset(nullstring, 0, sizeof(nullstring));
2187         iucv = NULL;
2188         sk = NULL;
2189         read_lock(&iucv_sk_list.lock);
2190         sk_for_each(sk, &iucv_sk_list.head) {
2191                 if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2192                         if ((!memcmp(&iucv_sk(sk)->src_name,
2193                                      trans_hdr->destAppName, 8)) &&
2194                             (!memcmp(&iucv_sk(sk)->src_user_id,
2195                                      trans_hdr->destUserID, 8)) &&
2196                             (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2197                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2198                                      nullstring, 8))) {
2199                                 iucv = iucv_sk(sk);
2200                                 break;
2201                         }
2202                 } else {
2203                         if ((!memcmp(&iucv_sk(sk)->src_name,
2204                                      trans_hdr->destAppName, 8)) &&
2205                             (!memcmp(&iucv_sk(sk)->src_user_id,
2206                                      trans_hdr->destUserID, 8)) &&
2207                             (!memcmp(&iucv_sk(sk)->dst_name,
2208                                      trans_hdr->srcAppName, 8)) &&
2209                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2210                                      trans_hdr->srcUserID, 8))) {
2211                                 iucv = iucv_sk(sk);
2212                                 break;
2213                         }
2214                 }
2215         }
2216         read_unlock(&iucv_sk_list.lock);
2217         if (!iucv)
2218                 sk = NULL;
2219
2220         /* no sock
2221         how should we send with no sock
2222         1) send without sock no send rc checking?
2223         2) introduce default sock to handle this cases
2224
2225          SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2226          data -> send FIN
2227          SYN|ACK, SYN|FIN, FIN -> no action? */
2228
2229         switch (trans_hdr->flags) {
2230         case AF_IUCV_FLAG_SYN:
2231                 /* connect request */
2232                 err = afiucv_hs_callback_syn(sk, skb);
2233                 break;
2234         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2235                 /* connect request confirmed */
2236                 err = afiucv_hs_callback_synack(sk, skb);
2237                 break;
2238         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2239                 /* connect request refused */
2240                 err = afiucv_hs_callback_synfin(sk, skb);
2241                 break;
2242         case (AF_IUCV_FLAG_FIN):
2243                 /* close request */
2244                 err = afiucv_hs_callback_fin(sk, skb);
2245                 break;
2246         case (AF_IUCV_FLAG_WIN):
2247                 err = afiucv_hs_callback_win(sk, skb);
2248                 if (skb->len == sizeof(struct af_iucv_trans_hdr)) {
2249                         kfree_skb(skb);
2250                         break;
2251                 }
2252                 /* fall through and receive non-zero length data */
2253         case (AF_IUCV_FLAG_SHT):
2254                 /* shutdown request */
2255                 /* fall through and receive zero length data */
2256         case 0:
2257                 /* plain data frame */
2258                 IUCV_SKB_CB(skb)->class = trans_hdr->iucv_hdr.class;
2259                 err = afiucv_hs_callback_rx(sk, skb);
2260                 break;
2261         default:
2262                 ;
2263         }
2264
2265         return err;
2266 }
2267
2268 /**
2269  * afiucv_hs_callback_txnotify() - handle send notifcations from HiperSockets
2270  *                                 transport
2271  **/
2272 static void afiucv_hs_callback_txnotify(struct sk_buff *skb,
2273                                         enum iucv_tx_notify n)
2274 {
2275         struct sock *isk = skb->sk;
2276         struct sock *sk = NULL;
2277         struct iucv_sock *iucv = NULL;
2278         struct sk_buff_head *list;
2279         struct sk_buff *list_skb;
2280         struct sk_buff *nskb;
2281         unsigned long flags;
2282
2283         read_lock_irqsave(&iucv_sk_list.lock, flags);
2284         sk_for_each(sk, &iucv_sk_list.head)
2285                 if (sk == isk) {
2286                         iucv = iucv_sk(sk);
2287                         break;
2288                 }
2289         read_unlock_irqrestore(&iucv_sk_list.lock, flags);
2290
2291         if (!iucv || sock_flag(sk, SOCK_ZAPPED))
2292                 return;
2293
2294         list = &iucv->send_skb_q;
2295         spin_lock_irqsave(&list->lock, flags);
2296         if (skb_queue_empty(list))
2297                 goto out_unlock;
2298         list_skb = list->next;
2299         nskb = list_skb->next;
2300         while (list_skb != (struct sk_buff *)list) {
2301                 if (skb_shinfo(list_skb) == skb_shinfo(skb)) {
2302                         switch (n) {
2303                         case TX_NOTIFY_OK:
2304                                 __skb_unlink(list_skb, list);
2305                                 kfree_skb(list_skb);
2306                                 iucv_sock_wake_msglim(sk);
2307                                 break;
2308                         case TX_NOTIFY_PENDING:
2309                                 atomic_inc(&iucv->pendings);
2310                                 break;
2311                         case TX_NOTIFY_DELAYED_OK:
2312                                 __skb_unlink(list_skb, list);
2313                                 atomic_dec(&iucv->pendings);
2314                                 if (atomic_read(&iucv->pendings) <= 0)
2315                                         iucv_sock_wake_msglim(sk);
2316                                 kfree_skb(list_skb);
2317                                 break;
2318                         case TX_NOTIFY_UNREACHABLE:
2319                         case TX_NOTIFY_DELAYED_UNREACHABLE:
2320                         case TX_NOTIFY_TPQFULL: /* not yet used */
2321                         case TX_NOTIFY_GENERALERROR:
2322                         case TX_NOTIFY_DELAYED_GENERALERROR:
2323                                 __skb_unlink(list_skb, list);
2324                                 kfree_skb(list_skb);
2325                                 if (sk->sk_state == IUCV_CONNECTED) {
2326                                         sk->sk_state = IUCV_DISCONN;
2327                                         sk->sk_state_change(sk);
2328                                 }
2329                                 break;
2330                         }
2331                         break;
2332                 }
2333                 list_skb = nskb;
2334                 nskb = nskb->next;
2335         }
2336 out_unlock:
2337         spin_unlock_irqrestore(&list->lock, flags);
2338
2339         if (sk->sk_state == IUCV_CLOSING) {
2340                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
2341                         sk->sk_state = IUCV_CLOSED;
2342                         sk->sk_state_change(sk);
2343                 }
2344         }
2345
2346 }
2347
2348 /*
2349  * afiucv_netdev_event: handle netdev notifier chain events
2350  */
2351 static int afiucv_netdev_event(struct notifier_block *this,
2352                                unsigned long event, void *ptr)
2353 {
2354         struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2355         struct sock *sk;
2356         struct iucv_sock *iucv;
2357
2358         switch (event) {
2359         case NETDEV_REBOOT:
2360         case NETDEV_GOING_DOWN:
2361                 sk_for_each(sk, &iucv_sk_list.head) {
2362                         iucv = iucv_sk(sk);
2363                         if ((iucv->hs_dev == event_dev) &&
2364                             (sk->sk_state == IUCV_CONNECTED)) {
2365                                 if (event == NETDEV_GOING_DOWN)
2366                                         iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
2367                                 sk->sk_state = IUCV_DISCONN;
2368                                 sk->sk_state_change(sk);
2369                         }
2370                 }
2371                 break;
2372         case NETDEV_DOWN:
2373         case NETDEV_UNREGISTER:
2374         default:
2375                 break;
2376         }
2377         return NOTIFY_DONE;
2378 }
2379
2380 static struct notifier_block afiucv_netdev_notifier = {
2381         .notifier_call = afiucv_netdev_event,
2382 };
2383
2384 static const struct proto_ops iucv_sock_ops = {
2385         .family         = PF_IUCV,
2386         .owner          = THIS_MODULE,
2387         .release        = iucv_sock_release,
2388         .bind           = iucv_sock_bind,
2389         .connect        = iucv_sock_connect,
2390         .listen         = iucv_sock_listen,
2391         .accept         = iucv_sock_accept,
2392         .getname        = iucv_sock_getname,
2393         .sendmsg        = iucv_sock_sendmsg,
2394         .recvmsg        = iucv_sock_recvmsg,
2395         .poll           = iucv_sock_poll,
2396         .ioctl          = sock_no_ioctl,
2397         .mmap           = sock_no_mmap,
2398         .socketpair     = sock_no_socketpair,
2399         .shutdown       = iucv_sock_shutdown,
2400         .setsockopt     = iucv_sock_setsockopt,
2401         .getsockopt     = iucv_sock_getsockopt,
2402 };
2403
2404 static const struct net_proto_family iucv_sock_family_ops = {
2405         .family = AF_IUCV,
2406         .owner  = THIS_MODULE,
2407         .create = iucv_sock_create,
2408 };
2409
2410 static struct packet_type iucv_packet_type = {
2411         .type = cpu_to_be16(ETH_P_AF_IUCV),
2412         .func = afiucv_hs_rcv,
2413 };
2414
2415 static int afiucv_iucv_init(void)
2416 {
2417         int err;
2418
2419         err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2420         if (err)
2421                 goto out;
2422         /* establish dummy device */
2423         af_iucv_driver.bus = pr_iucv->bus;
2424         err = driver_register(&af_iucv_driver);
2425         if (err)
2426                 goto out_iucv;
2427         af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2428         if (!af_iucv_dev) {
2429                 err = -ENOMEM;
2430                 goto out_driver;
2431         }
2432         dev_set_name(af_iucv_dev, "af_iucv");
2433         af_iucv_dev->bus = pr_iucv->bus;
2434         af_iucv_dev->parent = pr_iucv->root;
2435         af_iucv_dev->release = (void (*)(struct device *))kfree;
2436         af_iucv_dev->driver = &af_iucv_driver;
2437         err = device_register(af_iucv_dev);
2438         if (err)
2439                 goto out_driver;
2440         return 0;
2441
2442 out_driver:
2443         driver_unregister(&af_iucv_driver);
2444 out_iucv:
2445         pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2446 out:
2447         return err;
2448 }
2449
2450 static int __init afiucv_init(void)
2451 {
2452         int err;
2453
2454         if (MACHINE_IS_VM) {
2455                 cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2456                 if (unlikely(err)) {
2457                         WARN_ON(err);
2458                         err = -EPROTONOSUPPORT;
2459                         goto out;
2460                 }
2461
2462                 pr_iucv = try_then_request_module(symbol_get(iucv_if), "iucv");
2463                 if (!pr_iucv) {
2464                         printk(KERN_WARNING "iucv_if lookup failed\n");
2465                         memset(&iucv_userid, 0, sizeof(iucv_userid));
2466                 }
2467         } else {
2468                 memset(&iucv_userid, 0, sizeof(iucv_userid));
2469                 pr_iucv = NULL;
2470         }
2471
2472         err = proto_register(&iucv_proto, 0);
2473         if (err)
2474                 goto out;
2475         err = sock_register(&iucv_sock_family_ops);
2476         if (err)
2477                 goto out_proto;
2478
2479         if (pr_iucv) {
2480                 err = afiucv_iucv_init();
2481                 if (err)
2482                         goto out_sock;
2483         } else
2484                 register_netdevice_notifier(&afiucv_netdev_notifier);
2485         dev_add_pack(&iucv_packet_type);
2486         return 0;
2487
2488 out_sock:
2489         sock_unregister(PF_IUCV);
2490 out_proto:
2491         proto_unregister(&iucv_proto);
2492 out:
2493         if (pr_iucv)
2494                 symbol_put(iucv_if);
2495         return err;
2496 }
2497
2498 static void __exit afiucv_exit(void)
2499 {
2500         if (pr_iucv) {
2501                 device_unregister(af_iucv_dev);
2502                 driver_unregister(&af_iucv_driver);
2503                 pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2504                 symbol_put(iucv_if);
2505         } else
2506                 unregister_netdevice_notifier(&afiucv_netdev_notifier);
2507         dev_remove_pack(&iucv_packet_type);
2508         sock_unregister(PF_IUCV);
2509         proto_unregister(&iucv_proto);
2510 }
2511
2512 module_init(afiucv_init);
2513 module_exit(afiucv_exit);
2514
2515 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2516 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2517 MODULE_VERSION(VERSION);
2518 MODULE_LICENSE("GPL");
2519 MODULE_ALIAS_NETPROTO(PF_IUCV);
2520