64331158d6938f42709286efa04e2c3e67073208
[linux-2.6-microblaze.git] / net / iucv / af_iucv.c
1 /*
2  *  IUCV protocol stack for Linux on zSeries
3  *
4  *  Copyright IBM Corp. 2006, 2009
5  *
6  *  Author(s):  Jennifer Hunt <jenhunt@us.ibm.com>
7  *              Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
8  *  PM functions:
9  *              Ursula Braun <ursula.braun@de.ibm.com>
10  */
11
12 #define KMSG_COMPONENT "af_iucv"
13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
14
15 #include <linux/module.h>
16 #include <linux/types.h>
17 #include <linux/list.h>
18 #include <linux/errno.h>
19 #include <linux/kernel.h>
20 #include <linux/sched/signal.h>
21 #include <linux/slab.h>
22 #include <linux/skbuff.h>
23 #include <linux/init.h>
24 #include <linux/poll.h>
25 #include <linux/security.h>
26 #include <net/sock.h>
27 #include <asm/ebcdic.h>
28 #include <asm/cpcmd.h>
29 #include <linux/kmod.h>
30
31 #include <net/iucv/af_iucv.h>
32
33 #define VERSION "1.2"
34
35 static char iucv_userid[80];
36
37 static const struct proto_ops iucv_sock_ops;
38
39 static struct proto iucv_proto = {
40         .name           = "AF_IUCV",
41         .owner          = THIS_MODULE,
42         .obj_size       = sizeof(struct iucv_sock),
43 };
44
45 static struct iucv_interface *pr_iucv;
46
47 /* special AF_IUCV IPRM messages */
48 static const u8 iprm_shutdown[8] =
49         {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
50
51 #define TRGCLS_SIZE     (sizeof(((struct iucv_message *)0)->class))
52
53 #define __iucv_sock_wait(sk, condition, timeo, ret)                     \
54 do {                                                                    \
55         DEFINE_WAIT(__wait);                                            \
56         long __timeo = timeo;                                           \
57         ret = 0;                                                        \
58         prepare_to_wait(sk_sleep(sk), &__wait, TASK_INTERRUPTIBLE);     \
59         while (!(condition)) {                                          \
60                 if (!__timeo) {                                         \
61                         ret = -EAGAIN;                                  \
62                         break;                                          \
63                 }                                                       \
64                 if (signal_pending(current)) {                          \
65                         ret = sock_intr_errno(__timeo);                 \
66                         break;                                          \
67                 }                                                       \
68                 release_sock(sk);                                       \
69                 __timeo = schedule_timeout(__timeo);                    \
70                 lock_sock(sk);                                          \
71                 ret = sock_error(sk);                                   \
72                 if (ret)                                                \
73                         break;                                          \
74         }                                                               \
75         finish_wait(sk_sleep(sk), &__wait);                             \
76 } while (0)
77
78 #define iucv_sock_wait(sk, condition, timeo)                            \
79 ({                                                                      \
80         int __ret = 0;                                                  \
81         if (!(condition))                                               \
82                 __iucv_sock_wait(sk, condition, timeo, __ret);          \
83         __ret;                                                          \
84 })
85
86 static void iucv_sock_kill(struct sock *sk);
87 static void iucv_sock_close(struct sock *sk);
88 static void iucv_sever_path(struct sock *, int);
89
90 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
91         struct packet_type *pt, struct net_device *orig_dev);
92 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
93                    struct sk_buff *skb, u8 flags);
94 static void afiucv_hs_callback_txnotify(struct sk_buff *, enum iucv_tx_notify);
95
96 /* Call Back functions */
97 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
98 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
99 static void iucv_callback_connack(struct iucv_path *, u8 *);
100 static int iucv_callback_connreq(struct iucv_path *, u8 *, u8 *);
101 static void iucv_callback_connrej(struct iucv_path *, u8 *);
102 static void iucv_callback_shutdown(struct iucv_path *, u8 *);
103
104 static struct iucv_sock_list iucv_sk_list = {
105         .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
106         .autobind_name = ATOMIC_INIT(0)
107 };
108
109 static struct iucv_handler af_iucv_handler = {
110         .path_pending     = iucv_callback_connreq,
111         .path_complete    = iucv_callback_connack,
112         .path_severed     = iucv_callback_connrej,
113         .message_pending  = iucv_callback_rx,
114         .message_complete = iucv_callback_txdone,
115         .path_quiesced    = iucv_callback_shutdown,
116 };
117
118 static inline void high_nmcpy(unsigned char *dst, char *src)
119 {
120        memcpy(dst, src, 8);
121 }
122
123 static inline void low_nmcpy(unsigned char *dst, char *src)
124 {
125        memcpy(&dst[8], src, 8);
126 }
127
128 static int afiucv_pm_prepare(struct device *dev)
129 {
130 #ifdef CONFIG_PM_DEBUG
131         printk(KERN_WARNING "afiucv_pm_prepare\n");
132 #endif
133         return 0;
134 }
135
136 static void afiucv_pm_complete(struct device *dev)
137 {
138 #ifdef CONFIG_PM_DEBUG
139         printk(KERN_WARNING "afiucv_pm_complete\n");
140 #endif
141 }
142
143 /**
144  * afiucv_pm_freeze() - Freeze PM callback
145  * @dev:        AFIUCV dummy device
146  *
147  * Sever all established IUCV communication pathes
148  */
149 static int afiucv_pm_freeze(struct device *dev)
150 {
151         struct iucv_sock *iucv;
152         struct sock *sk;
153         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 = skb_push(skb, sizeof(struct af_iucv_trans_hdr));
326         skb_reset_mac_header(skb);
327         skb_reset_network_header(skb);
328         skb_push(skb, ETH_HLEN);
329         skb_reset_mac_header(skb);
330         memset(phs_hdr, 0, sizeof(struct af_iucv_trans_hdr));
331
332         phs_hdr->magic = ETH_P_AF_IUCV;
333         phs_hdr->version = 1;
334         phs_hdr->flags = flags;
335         if (flags == AF_IUCV_FLAG_SYN)
336                 phs_hdr->window = iucv->msglimit;
337         else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
338                 confirm_recv = atomic_read(&iucv->msg_recv);
339                 phs_hdr->window = confirm_recv;
340                 if (confirm_recv)
341                         phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
342         }
343         memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
344         memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
345         memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
346         memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
347         ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
348         ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
349         ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
350         ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
351         if (imsg)
352                 memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
353
354         skb->dev = iucv->hs_dev;
355         if (!skb->dev)
356                 return -ENODEV;
357         if (!(skb->dev->flags & IFF_UP) || !netif_carrier_ok(skb->dev))
358                 return -ENETDOWN;
359         if (skb->len > skb->dev->mtu) {
360                 if (sock->sk_type == SOCK_SEQPACKET)
361                         return -EMSGSIZE;
362                 else
363                         skb_trim(skb, skb->dev->mtu);
364         }
365         skb->protocol = cpu_to_be16(ETH_P_AF_IUCV);
366         nskb = skb_clone(skb, GFP_ATOMIC);
367         if (!nskb)
368                 return -ENOMEM;
369         skb_queue_tail(&iucv->send_skb_q, nskb);
370         err = dev_queue_xmit(skb);
371         if (net_xmit_eval(err)) {
372                 skb_unlink(nskb, &iucv->send_skb_q);
373                 kfree_skb(nskb);
374         } else {
375                 atomic_sub(confirm_recv, &iucv->msg_recv);
376                 WARN_ON(atomic_read(&iucv->msg_recv) < 0);
377         }
378         return net_xmit_eval(err);
379 }
380
381 static struct sock *__iucv_get_sock_by_name(char *nm)
382 {
383         struct sock *sk;
384
385         sk_for_each(sk, &iucv_sk_list.head)
386                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
387                         return sk;
388
389         return NULL;
390 }
391
392 static void iucv_sock_destruct(struct sock *sk)
393 {
394         skb_queue_purge(&sk->sk_receive_queue);
395         skb_queue_purge(&sk->sk_error_queue);
396
397         sk_mem_reclaim(sk);
398
399         if (!sock_flag(sk, SOCK_DEAD)) {
400                 pr_err("Attempt to release alive iucv socket %p\n", sk);
401                 return;
402         }
403
404         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
405         WARN_ON(refcount_read(&sk->sk_wmem_alloc));
406         WARN_ON(sk->sk_wmem_queued);
407         WARN_ON(sk->sk_forward_alloc);
408 }
409
410 /* Cleanup Listen */
411 static void iucv_sock_cleanup_listen(struct sock *parent)
412 {
413         struct sock *sk;
414
415         /* Close non-accepted connections */
416         while ((sk = iucv_accept_dequeue(parent, NULL))) {
417                 iucv_sock_close(sk);
418                 iucv_sock_kill(sk);
419         }
420
421         parent->sk_state = IUCV_CLOSED;
422 }
423
424 /* Kill socket (only if zapped and orphaned) */
425 static void iucv_sock_kill(struct sock *sk)
426 {
427         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
428                 return;
429
430         iucv_sock_unlink(&iucv_sk_list, sk);
431         sock_set_flag(sk, SOCK_DEAD);
432         sock_put(sk);
433 }
434
435 /* Terminate an IUCV path */
436 static void iucv_sever_path(struct sock *sk, int with_user_data)
437 {
438         unsigned char user_data[16];
439         struct iucv_sock *iucv = iucv_sk(sk);
440         struct iucv_path *path = iucv->path;
441
442         if (iucv->path) {
443                 iucv->path = NULL;
444                 if (with_user_data) {
445                         low_nmcpy(user_data, iucv->src_name);
446                         high_nmcpy(user_data, iucv->dst_name);
447                         ASCEBC(user_data, sizeof(user_data));
448                         pr_iucv->path_sever(path, user_data);
449                 } else
450                         pr_iucv->path_sever(path, NULL);
451                 iucv_path_free(path);
452         }
453 }
454
455 /* Send controlling flags through an IUCV socket for HIPER transport */
456 static int iucv_send_ctrl(struct sock *sk, u8 flags)
457 {
458         int err = 0;
459         int blen;
460         struct sk_buff *skb;
461         u8 shutdown = 0;
462
463         blen = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
464         if (sk->sk_shutdown & SEND_SHUTDOWN) {
465                 /* controlling flags should be sent anyway */
466                 shutdown = sk->sk_shutdown;
467                 sk->sk_shutdown &= RCV_SHUTDOWN;
468         }
469         skb = sock_alloc_send_skb(sk, blen, 1, &err);
470         if (skb) {
471                 skb_reserve(skb, blen);
472                 err = afiucv_hs_send(NULL, sk, skb, flags);
473         }
474         if (shutdown)
475                 sk->sk_shutdown = shutdown;
476         return err;
477 }
478
479 /* Close an IUCV socket */
480 static void iucv_sock_close(struct sock *sk)
481 {
482         struct iucv_sock *iucv = iucv_sk(sk);
483         unsigned long timeo;
484         int err = 0;
485
486         lock_sock(sk);
487
488         switch (sk->sk_state) {
489         case IUCV_LISTEN:
490                 iucv_sock_cleanup_listen(sk);
491                 break;
492
493         case IUCV_CONNECTED:
494                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
495                         err = iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
496                         sk->sk_state = IUCV_DISCONN;
497                         sk->sk_state_change(sk);
498                 }
499         case IUCV_DISCONN:   /* fall through */
500                 sk->sk_state = IUCV_CLOSING;
501                 sk->sk_state_change(sk);
502
503                 if (!err && !skb_queue_empty(&iucv->send_skb_q)) {
504                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
505                                 timeo = sk->sk_lingertime;
506                         else
507                                 timeo = IUCV_DISCONN_TIMEOUT;
508                         iucv_sock_wait(sk,
509                                         iucv_sock_in_state(sk, IUCV_CLOSED, 0),
510                                         timeo);
511                 }
512
513         case IUCV_CLOSING:   /* fall through */
514                 sk->sk_state = IUCV_CLOSED;
515                 sk->sk_state_change(sk);
516
517                 sk->sk_err = ECONNRESET;
518                 sk->sk_state_change(sk);
519
520                 skb_queue_purge(&iucv->send_skb_q);
521                 skb_queue_purge(&iucv->backlog_skb_q);
522
523         default:   /* fall through */
524                 iucv_sever_path(sk, 1);
525         }
526
527         if (iucv->hs_dev) {
528                 dev_put(iucv->hs_dev);
529                 iucv->hs_dev = NULL;
530                 sk->sk_bound_dev_if = 0;
531         }
532
533         /* mark socket for deletion by iucv_sock_kill() */
534         sock_set_flag(sk, SOCK_ZAPPED);
535
536         release_sock(sk);
537 }
538
539 static void iucv_sock_init(struct sock *sk, struct sock *parent)
540 {
541         if (parent) {
542                 sk->sk_type = parent->sk_type;
543                 security_sk_clone(parent, sk);
544         }
545 }
546
547 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio, int kern)
548 {
549         struct sock *sk;
550         struct iucv_sock *iucv;
551
552         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto, kern);
553         if (!sk)
554                 return NULL;
555         iucv = iucv_sk(sk);
556
557         sock_init_data(sock, sk);
558         INIT_LIST_HEAD(&iucv->accept_q);
559         spin_lock_init(&iucv->accept_q_lock);
560         skb_queue_head_init(&iucv->send_skb_q);
561         INIT_LIST_HEAD(&iucv->message_q.list);
562         spin_lock_init(&iucv->message_q.lock);
563         skb_queue_head_init(&iucv->backlog_skb_q);
564         iucv->send_tag = 0;
565         atomic_set(&iucv->pendings, 0);
566         iucv->flags = 0;
567         iucv->msglimit = 0;
568         atomic_set(&iucv->msg_sent, 0);
569         atomic_set(&iucv->msg_recv, 0);
570         iucv->path = NULL;
571         iucv->sk_txnotify = afiucv_hs_callback_txnotify;
572         memset(&iucv->src_user_id , 0, 32);
573         if (pr_iucv)
574                 iucv->transport = AF_IUCV_TRANS_IUCV;
575         else
576                 iucv->transport = AF_IUCV_TRANS_HIPER;
577
578         sk->sk_destruct = iucv_sock_destruct;
579         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
580         sk->sk_allocation = GFP_DMA;
581
582         sock_reset_flag(sk, SOCK_ZAPPED);
583
584         sk->sk_protocol = proto;
585         sk->sk_state    = IUCV_OPEN;
586
587         iucv_sock_link(&iucv_sk_list, sk);
588         return sk;
589 }
590
591 /* Create an IUCV socket */
592 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
593                             int kern)
594 {
595         struct sock *sk;
596
597         if (protocol && protocol != PF_IUCV)
598                 return -EPROTONOSUPPORT;
599
600         sock->state = SS_UNCONNECTED;
601
602         switch (sock->type) {
603         case SOCK_STREAM:
604                 sock->ops = &iucv_sock_ops;
605                 break;
606         case SOCK_SEQPACKET:
607                 /* currently, proto ops can handle both sk types */
608                 sock->ops = &iucv_sock_ops;
609                 break;
610         default:
611                 return -ESOCKTNOSUPPORT;
612         }
613
614         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL, kern);
615         if (!sk)
616                 return -ENOMEM;
617
618         iucv_sock_init(sk, NULL);
619
620         return 0;
621 }
622
623 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
624 {
625         write_lock_bh(&l->lock);
626         sk_add_node(sk, &l->head);
627         write_unlock_bh(&l->lock);
628 }
629
630 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
631 {
632         write_lock_bh(&l->lock);
633         sk_del_node_init(sk);
634         write_unlock_bh(&l->lock);
635 }
636
637 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
638 {
639         unsigned long flags;
640         struct iucv_sock *par = iucv_sk(parent);
641
642         sock_hold(sk);
643         spin_lock_irqsave(&par->accept_q_lock, flags);
644         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
645         spin_unlock_irqrestore(&par->accept_q_lock, flags);
646         iucv_sk(sk)->parent = parent;
647         sk_acceptq_added(parent);
648 }
649
650 void iucv_accept_unlink(struct sock *sk)
651 {
652         unsigned long flags;
653         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
654
655         spin_lock_irqsave(&par->accept_q_lock, flags);
656         list_del_init(&iucv_sk(sk)->accept_q);
657         spin_unlock_irqrestore(&par->accept_q_lock, flags);
658         sk_acceptq_removed(iucv_sk(sk)->parent);
659         iucv_sk(sk)->parent = NULL;
660         sock_put(sk);
661 }
662
663 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
664 {
665         struct iucv_sock *isk, *n;
666         struct sock *sk;
667
668         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
669                 sk = (struct sock *) isk;
670                 lock_sock(sk);
671
672                 if (sk->sk_state == IUCV_CLOSED) {
673                         iucv_accept_unlink(sk);
674                         release_sock(sk);
675                         continue;
676                 }
677
678                 if (sk->sk_state == IUCV_CONNECTED ||
679                     sk->sk_state == IUCV_DISCONN ||
680                     !newsock) {
681                         iucv_accept_unlink(sk);
682                         if (newsock)
683                                 sock_graft(sk, newsock);
684
685                         release_sock(sk);
686                         return sk;
687                 }
688
689                 release_sock(sk);
690         }
691         return NULL;
692 }
693
694 static void __iucv_auto_name(struct iucv_sock *iucv)
695 {
696         char name[12];
697
698         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
699         while (__iucv_get_sock_by_name(name)) {
700                 sprintf(name, "%08x",
701                         atomic_inc_return(&iucv_sk_list.autobind_name));
702         }
703         memcpy(iucv->src_name, name, 8);
704 }
705
706 /* Bind an unbound socket */
707 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
708                           int addr_len)
709 {
710         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
711         struct sock *sk = sock->sk;
712         struct iucv_sock *iucv;
713         int err = 0;
714         struct net_device *dev;
715         char uid[9];
716
717         /* Verify the input sockaddr */
718         if (addr_len < sizeof(struct sockaddr_iucv) ||
719             addr->sa_family != AF_IUCV)
720                 return -EINVAL;
721
722         lock_sock(sk);
723         if (sk->sk_state != IUCV_OPEN) {
724                 err = -EBADFD;
725                 goto done;
726         }
727
728         write_lock_bh(&iucv_sk_list.lock);
729
730         iucv = iucv_sk(sk);
731         if (__iucv_get_sock_by_name(sa->siucv_name)) {
732                 err = -EADDRINUSE;
733                 goto done_unlock;
734         }
735         if (iucv->path)
736                 goto done_unlock;
737
738         /* Bind the socket */
739         if (pr_iucv)
740                 if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
741                         goto vm_bind; /* VM IUCV transport */
742
743         /* try hiper transport */
744         memcpy(uid, sa->siucv_user_id, sizeof(uid));
745         ASCEBC(uid, 8);
746         rcu_read_lock();
747         for_each_netdev_rcu(&init_net, dev) {
748                 if (!memcmp(dev->perm_addr, uid, 8)) {
749                         memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
750                         /* Check for unitialized siucv_name */
751                         if (strncmp(sa->siucv_name, "        ", 8) == 0)
752                                 __iucv_auto_name(iucv);
753                         else
754                                 memcpy(iucv->src_name, sa->siucv_name, 8);
755                         sk->sk_bound_dev_if = dev->ifindex;
756                         iucv->hs_dev = dev;
757                         dev_hold(dev);
758                         sk->sk_state = IUCV_BOUND;
759                         iucv->transport = AF_IUCV_TRANS_HIPER;
760                         if (!iucv->msglimit)
761                                 iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
762                         rcu_read_unlock();
763                         goto done_unlock;
764                 }
765         }
766         rcu_read_unlock();
767 vm_bind:
768         if (pr_iucv) {
769                 /* use local userid for backward compat */
770                 memcpy(iucv->src_name, sa->siucv_name, 8);
771                 memcpy(iucv->src_user_id, iucv_userid, 8);
772                 sk->sk_state = IUCV_BOUND;
773                 iucv->transport = AF_IUCV_TRANS_IUCV;
774                 if (!iucv->msglimit)
775                         iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
776                 goto done_unlock;
777         }
778         /* found no dev to bind */
779         err = -ENODEV;
780 done_unlock:
781         /* Release the socket list lock */
782         write_unlock_bh(&iucv_sk_list.lock);
783 done:
784         release_sock(sk);
785         return err;
786 }
787
788 /* Automatically bind an unbound socket */
789 static int iucv_sock_autobind(struct sock *sk)
790 {
791         struct iucv_sock *iucv = iucv_sk(sk);
792         int err = 0;
793
794         if (unlikely(!pr_iucv))
795                 return -EPROTO;
796
797         memcpy(iucv->src_user_id, iucv_userid, 8);
798
799         write_lock_bh(&iucv_sk_list.lock);
800         __iucv_auto_name(iucv);
801         write_unlock_bh(&iucv_sk_list.lock);
802
803         if (!iucv->msglimit)
804                 iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
805
806         return err;
807 }
808
809 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
810 {
811         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
812         struct sock *sk = sock->sk;
813         struct iucv_sock *iucv = iucv_sk(sk);
814         unsigned char user_data[16];
815         int err;
816
817         high_nmcpy(user_data, sa->siucv_name);
818         low_nmcpy(user_data, iucv->src_name);
819         ASCEBC(user_data, sizeof(user_data));
820
821         /* Create path. */
822         iucv->path = iucv_path_alloc(iucv->msglimit,
823                                      IUCV_IPRMDATA, GFP_KERNEL);
824         if (!iucv->path) {
825                 err = -ENOMEM;
826                 goto done;
827         }
828         err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
829                                     sa->siucv_user_id, NULL, user_data,
830                                     sk);
831         if (err) {
832                 iucv_path_free(iucv->path);
833                 iucv->path = NULL;
834                 switch (err) {
835                 case 0x0b:      /* Target communicator is not logged on */
836                         err = -ENETUNREACH;
837                         break;
838                 case 0x0d:      /* Max connections for this guest exceeded */
839                 case 0x0e:      /* Max connections for target guest exceeded */
840                         err = -EAGAIN;
841                         break;
842                 case 0x0f:      /* Missing IUCV authorization */
843                         err = -EACCES;
844                         break;
845                 default:
846                         err = -ECONNREFUSED;
847                         break;
848                 }
849         }
850 done:
851         return err;
852 }
853
854 /* Connect an unconnected socket */
855 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
856                              int alen, int flags)
857 {
858         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
859         struct sock *sk = sock->sk;
860         struct iucv_sock *iucv = iucv_sk(sk);
861         int err;
862
863         if (alen < sizeof(struct sockaddr_iucv) || addr->sa_family != AF_IUCV)
864                 return -EINVAL;
865
866         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
867                 return -EBADFD;
868
869         if (sk->sk_state == IUCV_OPEN &&
870             iucv->transport == AF_IUCV_TRANS_HIPER)
871                 return -EBADFD; /* explicit bind required */
872
873         if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
874                 return -EINVAL;
875
876         if (sk->sk_state == IUCV_OPEN) {
877                 err = iucv_sock_autobind(sk);
878                 if (unlikely(err))
879                         return err;
880         }
881
882         lock_sock(sk);
883
884         /* Set the destination information */
885         memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
886         memcpy(iucv->dst_name, sa->siucv_name, 8);
887
888         if (iucv->transport == AF_IUCV_TRANS_HIPER)
889                 err = iucv_send_ctrl(sock->sk, AF_IUCV_FLAG_SYN);
890         else
891                 err = afiucv_path_connect(sock, addr);
892         if (err)
893                 goto done;
894
895         if (sk->sk_state != IUCV_CONNECTED)
896                 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
897                                                             IUCV_DISCONN),
898                                      sock_sndtimeo(sk, flags & O_NONBLOCK));
899
900         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
901                 err = -ECONNREFUSED;
902
903         if (err && iucv->transport == AF_IUCV_TRANS_IUCV)
904                 iucv_sever_path(sk, 0);
905
906 done:
907         release_sock(sk);
908         return err;
909 }
910
911 /* Move a socket into listening state. */
912 static int iucv_sock_listen(struct socket *sock, int backlog)
913 {
914         struct sock *sk = sock->sk;
915         int err;
916
917         lock_sock(sk);
918
919         err = -EINVAL;
920         if (sk->sk_state != IUCV_BOUND)
921                 goto done;
922
923         if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
924                 goto done;
925
926         sk->sk_max_ack_backlog = backlog;
927         sk->sk_ack_backlog = 0;
928         sk->sk_state = IUCV_LISTEN;
929         err = 0;
930
931 done:
932         release_sock(sk);
933         return err;
934 }
935
936 /* Accept a pending connection */
937 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
938                             int flags, bool kern)
939 {
940         DECLARE_WAITQUEUE(wait, current);
941         struct sock *sk = sock->sk, *nsk;
942         long timeo;
943         int err = 0;
944
945         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
946
947         if (sk->sk_state != IUCV_LISTEN) {
948                 err = -EBADFD;
949                 goto done;
950         }
951
952         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
953
954         /* Wait for an incoming connection */
955         add_wait_queue_exclusive(sk_sleep(sk), &wait);
956         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
957                 set_current_state(TASK_INTERRUPTIBLE);
958                 if (!timeo) {
959                         err = -EAGAIN;
960                         break;
961                 }
962
963                 release_sock(sk);
964                 timeo = schedule_timeout(timeo);
965                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
966
967                 if (sk->sk_state != IUCV_LISTEN) {
968                         err = -EBADFD;
969                         break;
970                 }
971
972                 if (signal_pending(current)) {
973                         err = sock_intr_errno(timeo);
974                         break;
975                 }
976         }
977
978         set_current_state(TASK_RUNNING);
979         remove_wait_queue(sk_sleep(sk), &wait);
980
981         if (err)
982                 goto done;
983
984         newsock->state = SS_CONNECTED;
985
986 done:
987         release_sock(sk);
988         return err;
989 }
990
991 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
992                              int *len, int peer)
993 {
994         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
995         struct sock *sk = sock->sk;
996         struct iucv_sock *iucv = iucv_sk(sk);
997
998         addr->sa_family = AF_IUCV;
999         *len = sizeof(struct sockaddr_iucv);
1000
1001         if (peer) {
1002                 memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
1003                 memcpy(siucv->siucv_name, iucv->dst_name, 8);
1004         } else {
1005                 memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
1006                 memcpy(siucv->siucv_name, iucv->src_name, 8);
1007         }
1008         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
1009         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
1010         memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
1011
1012         return 0;
1013 }
1014
1015 /**
1016  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
1017  * @path:       IUCV path
1018  * @msg:        Pointer to a struct iucv_message
1019  * @skb:        The socket data to send, skb->len MUST BE <= 7
1020  *
1021  * Send the socket data in the parameter list in the iucv message
1022  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
1023  * list and the socket data len at index 7 (last byte).
1024  * See also iucv_msg_length().
1025  *
1026  * Returns the error code from the iucv_message_send() call.
1027  */
1028 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
1029                           struct sk_buff *skb)
1030 {
1031         u8 prmdata[8];
1032
1033         memcpy(prmdata, (void *) skb->data, skb->len);
1034         prmdata[7] = 0xff - (u8) skb->len;
1035         return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
1036                                  (void *) prmdata, 8);
1037 }
1038
1039 static int iucv_sock_sendmsg(struct socket *sock, struct msghdr *msg,
1040                              size_t len)
1041 {
1042         struct sock *sk = sock->sk;
1043         struct iucv_sock *iucv = iucv_sk(sk);
1044         size_t headroom = 0;
1045         size_t linear;
1046         struct sk_buff *skb;
1047         struct iucv_message txmsg = {0};
1048         struct cmsghdr *cmsg;
1049         int cmsg_done;
1050         long timeo;
1051         char user_id[9];
1052         char appl_id[9];
1053         int err;
1054         int noblock = msg->msg_flags & MSG_DONTWAIT;
1055
1056         err = sock_error(sk);
1057         if (err)
1058                 return err;
1059
1060         if (msg->msg_flags & MSG_OOB)
1061                 return -EOPNOTSUPP;
1062
1063         /* SOCK_SEQPACKET: we do not support segmented records */
1064         if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
1065                 return -EOPNOTSUPP;
1066
1067         lock_sock(sk);
1068
1069         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1070                 err = -EPIPE;
1071                 goto out;
1072         }
1073
1074         /* Return if the socket is not in connected state */
1075         if (sk->sk_state != IUCV_CONNECTED) {
1076                 err = -ENOTCONN;
1077                 goto out;
1078         }
1079
1080         /* initialize defaults */
1081         cmsg_done   = 0;        /* check for duplicate headers */
1082         txmsg.class = 0;
1083
1084         /* iterate over control messages */
1085         for_each_cmsghdr(cmsg, msg) {
1086                 if (!CMSG_OK(msg, cmsg)) {
1087                         err = -EINVAL;
1088                         goto out;
1089                 }
1090
1091                 if (cmsg->cmsg_level != SOL_IUCV)
1092                         continue;
1093
1094                 if (cmsg->cmsg_type & cmsg_done) {
1095                         err = -EINVAL;
1096                         goto out;
1097                 }
1098                 cmsg_done |= cmsg->cmsg_type;
1099
1100                 switch (cmsg->cmsg_type) {
1101                 case SCM_IUCV_TRGCLS:
1102                         if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
1103                                 err = -EINVAL;
1104                                 goto out;
1105                         }
1106
1107                         /* set iucv message target class */
1108                         memcpy(&txmsg.class,
1109                                 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
1110
1111                         break;
1112
1113                 default:
1114                         err = -EINVAL;
1115                         goto out;
1116                 }
1117         }
1118
1119         /* allocate one skb for each iucv message:
1120          * this is fine for SOCK_SEQPACKET (unless we want to support
1121          * segmented records using the MSG_EOR flag), but
1122          * for SOCK_STREAM we might want to improve it in future */
1123         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1124                 headroom = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
1125                 linear = len;
1126         } else {
1127                 if (len < PAGE_SIZE) {
1128                         linear = len;
1129                 } else {
1130                         /* In nonlinear "classic" iucv skb,
1131                          * reserve space for iucv_array
1132                          */
1133                         headroom = sizeof(struct iucv_array) *
1134                                    (MAX_SKB_FRAGS + 1);
1135                         linear = PAGE_SIZE - headroom;
1136                 }
1137         }
1138         skb = sock_alloc_send_pskb(sk, headroom + linear, len - linear,
1139                                    noblock, &err, 0);
1140         if (!skb)
1141                 goto out;
1142         if (headroom)
1143                 skb_reserve(skb, headroom);
1144         skb_put(skb, linear);
1145         skb->len = len;
1146         skb->data_len = len - linear;
1147         err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, len);
1148         if (err)
1149                 goto fail;
1150
1151         /* wait if outstanding messages for iucv path has reached */
1152         timeo = sock_sndtimeo(sk, noblock);
1153         err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1154         if (err)
1155                 goto fail;
1156
1157         /* return -ECONNRESET if the socket is no longer connected */
1158         if (sk->sk_state != IUCV_CONNECTED) {
1159                 err = -ECONNRESET;
1160                 goto fail;
1161         }
1162
1163         /* increment and save iucv message tag for msg_completion cbk */
1164         txmsg.tag = iucv->send_tag++;
1165         IUCV_SKB_CB(skb)->tag = txmsg.tag;
1166
1167         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1168                 atomic_inc(&iucv->msg_sent);
1169                 err = afiucv_hs_send(&txmsg, sk, skb, 0);
1170                 if (err) {
1171                         atomic_dec(&iucv->msg_sent);
1172                         goto fail;
1173                 }
1174         } else { /* Classic VM IUCV transport */
1175                 skb_queue_tail(&iucv->send_skb_q, skb);
1176
1177                 if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags) &&
1178                     skb->len <= 7) {
1179                         err = iucv_send_iprm(iucv->path, &txmsg, skb);
1180
1181                         /* on success: there is no message_complete callback */
1182                         /* for an IPRMDATA msg; remove skb from send queue   */
1183                         if (err == 0) {
1184                                 skb_unlink(skb, &iucv->send_skb_q);
1185                                 kfree_skb(skb);
1186                         }
1187
1188                         /* this error should never happen since the     */
1189                         /* IUCV_IPRMDATA path flag is set... sever path */
1190                         if (err == 0x15) {
1191                                 pr_iucv->path_sever(iucv->path, NULL);
1192                                 skb_unlink(skb, &iucv->send_skb_q);
1193                                 err = -EPIPE;
1194                                 goto fail;
1195                         }
1196                 } else if (skb_is_nonlinear(skb)) {
1197                         struct iucv_array *iba = (struct iucv_array *)skb->head;
1198                         int i;
1199
1200                         /* skip iucv_array lying in the headroom */
1201                         iba[0].address = (u32)(addr_t)skb->data;
1202                         iba[0].length = (u32)skb_headlen(skb);
1203                         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1204                                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1205
1206                                 iba[i + 1].address =
1207                                         (u32)(addr_t)skb_frag_address(frag);
1208                                 iba[i + 1].length = (u32)skb_frag_size(frag);
1209                         }
1210                         err = pr_iucv->message_send(iucv->path, &txmsg,
1211                                                     IUCV_IPBUFLST, 0,
1212                                                     (void *)iba, skb->len);
1213                 } else { /* non-IPRM Linear skb */
1214                         err = pr_iucv->message_send(iucv->path, &txmsg,
1215                                         0, 0, (void *)skb->data, skb->len);
1216                 }
1217                 if (err) {
1218                         if (err == 3) {
1219                                 user_id[8] = 0;
1220                                 memcpy(user_id, iucv->dst_user_id, 8);
1221                                 appl_id[8] = 0;
1222                                 memcpy(appl_id, iucv->dst_name, 8);
1223                                 pr_err(
1224                 "Application %s on z/VM guest %s exceeds message limit\n",
1225                                         appl_id, user_id);
1226                                 err = -EAGAIN;
1227                         } else {
1228                                 err = -EPIPE;
1229                         }
1230                         skb_unlink(skb, &iucv->send_skb_q);
1231                         goto fail;
1232                 }
1233         }
1234
1235         release_sock(sk);
1236         return len;
1237
1238 fail:
1239         kfree_skb(skb);
1240 out:
1241         release_sock(sk);
1242         return err;
1243 }
1244
1245 static struct sk_buff *alloc_iucv_recv_skb(unsigned long len)
1246 {
1247         size_t headroom, linear;
1248         struct sk_buff *skb;
1249         int err;
1250
1251         if (len < PAGE_SIZE) {
1252                 headroom = 0;
1253                 linear = len;
1254         } else {
1255                 headroom = sizeof(struct iucv_array) * (MAX_SKB_FRAGS + 1);
1256                 linear = PAGE_SIZE - headroom;
1257         }
1258         skb = alloc_skb_with_frags(headroom + linear, len - linear,
1259                                    0, &err, GFP_ATOMIC | GFP_DMA);
1260         WARN_ONCE(!skb,
1261                   "alloc of recv iucv skb len=%lu failed with errcode=%d\n",
1262                   len, err);
1263         if (skb) {
1264                 if (headroom)
1265                         skb_reserve(skb, headroom);
1266                 skb_put(skb, linear);
1267                 skb->len = len;
1268                 skb->data_len = len - linear;
1269         }
1270         return skb;
1271 }
1272
1273 /* iucv_process_message() - Receive a single outstanding IUCV message
1274  *
1275  * Locking: must be called with message_q.lock held
1276  */
1277 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1278                                  struct iucv_path *path,
1279                                  struct iucv_message *msg)
1280 {
1281         int rc;
1282         unsigned int len;
1283
1284         len = iucv_msg_length(msg);
1285
1286         /* store msg target class in the second 4 bytes of skb ctrl buffer */
1287         /* Note: the first 4 bytes are reserved for msg tag */
1288         IUCV_SKB_CB(skb)->class = msg->class;
1289
1290         /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1291         if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1292                 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1293                         skb->data = NULL;
1294                         skb->len = 0;
1295                 }
1296         } else {
1297                 if (skb_is_nonlinear(skb)) {
1298                         struct iucv_array *iba = (struct iucv_array *)skb->head;
1299                         int i;
1300
1301                         iba[0].address = (u32)(addr_t)skb->data;
1302                         iba[0].length = (u32)skb_headlen(skb);
1303                         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1304                                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1305
1306                                 iba[i + 1].address =
1307                                         (u32)(addr_t)skb_frag_address(frag);
1308                                 iba[i + 1].length = (u32)skb_frag_size(frag);
1309                         }
1310                         rc = pr_iucv->message_receive(path, msg,
1311                                               IUCV_IPBUFLST,
1312                                               (void *)iba, len, NULL);
1313                 } else {
1314                         rc = pr_iucv->message_receive(path, msg,
1315                                               msg->flags & IUCV_IPRMDATA,
1316                                               skb->data, len, NULL);
1317                 }
1318                 if (rc) {
1319                         kfree_skb(skb);
1320                         return;
1321                 }
1322                 WARN_ON_ONCE(skb->len != len);
1323         }
1324
1325         IUCV_SKB_CB(skb)->offset = 0;
1326         if (sk_filter(sk, skb)) {
1327                 atomic_inc(&sk->sk_drops);      /* skb rejected by filter */
1328                 kfree_skb(skb);
1329                 return;
1330         }
1331         if (__sock_queue_rcv_skb(sk, skb))      /* handle rcv queue full */
1332                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
1333 }
1334
1335 /* iucv_process_message_q() - Process outstanding IUCV messages
1336  *
1337  * Locking: must be called with message_q.lock held
1338  */
1339 static void iucv_process_message_q(struct sock *sk)
1340 {
1341         struct iucv_sock *iucv = iucv_sk(sk);
1342         struct sk_buff *skb;
1343         struct sock_msg_q *p, *n;
1344
1345         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1346                 skb = alloc_iucv_recv_skb(iucv_msg_length(&p->msg));
1347                 if (!skb)
1348                         break;
1349                 iucv_process_message(sk, skb, p->path, &p->msg);
1350                 list_del(&p->list);
1351                 kfree(p);
1352                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1353                         break;
1354         }
1355 }
1356
1357 static int iucv_sock_recvmsg(struct socket *sock, struct msghdr *msg,
1358                              size_t len, int flags)
1359 {
1360         int noblock = flags & MSG_DONTWAIT;
1361         struct sock *sk = sock->sk;
1362         struct iucv_sock *iucv = iucv_sk(sk);
1363         unsigned int copied, rlen;
1364         struct sk_buff *skb, *rskb, *cskb;
1365         int err = 0;
1366         u32 offset;
1367
1368         if ((sk->sk_state == IUCV_DISCONN) &&
1369             skb_queue_empty(&iucv->backlog_skb_q) &&
1370             skb_queue_empty(&sk->sk_receive_queue) &&
1371             list_empty(&iucv->message_q.list))
1372                 return 0;
1373
1374         if (flags & (MSG_OOB))
1375                 return -EOPNOTSUPP;
1376
1377         /* receive/dequeue next skb:
1378          * the function understands MSG_PEEK and, thus, does not dequeue skb */
1379         skb = skb_recv_datagram(sk, flags, noblock, &err);
1380         if (!skb) {
1381                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1382                         return 0;
1383                 return err;
1384         }
1385
1386         offset = IUCV_SKB_CB(skb)->offset;
1387         rlen   = skb->len - offset;             /* real length of skb */
1388         copied = min_t(unsigned int, rlen, len);
1389         if (!rlen)
1390                 sk->sk_shutdown = sk->sk_shutdown | RCV_SHUTDOWN;
1391
1392         cskb = skb;
1393         if (skb_copy_datagram_msg(cskb, offset, msg, copied)) {
1394                 if (!(flags & MSG_PEEK))
1395                         skb_queue_head(&sk->sk_receive_queue, skb);
1396                 return -EFAULT;
1397         }
1398
1399         /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1400         if (sk->sk_type == SOCK_SEQPACKET) {
1401                 if (copied < rlen)
1402                         msg->msg_flags |= MSG_TRUNC;
1403                 /* each iucv message contains a complete record */
1404                 msg->msg_flags |= MSG_EOR;
1405         }
1406
1407         /* create control message to store iucv msg target class:
1408          * get the trgcls from the control buffer of the skb due to
1409          * fragmentation of original iucv message. */
1410         err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1411                        sizeof(IUCV_SKB_CB(skb)->class),
1412                        (void *)&IUCV_SKB_CB(skb)->class);
1413         if (err) {
1414                 if (!(flags & MSG_PEEK))
1415                         skb_queue_head(&sk->sk_receive_queue, skb);
1416                 return err;
1417         }
1418
1419         /* Mark read part of skb as used */
1420         if (!(flags & MSG_PEEK)) {
1421
1422                 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1423                 if (sk->sk_type == SOCK_STREAM) {
1424                         if (copied < rlen) {
1425                                 IUCV_SKB_CB(skb)->offset = offset + copied;
1426                                 skb_queue_head(&sk->sk_receive_queue, skb);
1427                                 goto done;
1428                         }
1429                 }
1430
1431                 kfree_skb(skb);
1432                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1433                         atomic_inc(&iucv->msg_recv);
1434                         if (atomic_read(&iucv->msg_recv) > iucv->msglimit) {
1435                                 WARN_ON(1);
1436                                 iucv_sock_close(sk);
1437                                 return -EFAULT;
1438                         }
1439                 }
1440
1441                 /* Queue backlog skbs */
1442                 spin_lock_bh(&iucv->message_q.lock);
1443                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1444                 while (rskb) {
1445                         IUCV_SKB_CB(rskb)->offset = 0;
1446                         if (__sock_queue_rcv_skb(sk, rskb)) {
1447                                 /* handle rcv queue full */
1448                                 skb_queue_head(&iucv->backlog_skb_q,
1449                                                 rskb);
1450                                 break;
1451                         }
1452                         rskb = skb_dequeue(&iucv->backlog_skb_q);
1453                 }
1454                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1455                         if (!list_empty(&iucv->message_q.list))
1456                                 iucv_process_message_q(sk);
1457                         if (atomic_read(&iucv->msg_recv) >=
1458                                                         iucv->msglimit / 2) {
1459                                 err = iucv_send_ctrl(sk, AF_IUCV_FLAG_WIN);
1460                                 if (err) {
1461                                         sk->sk_state = IUCV_DISCONN;
1462                                         sk->sk_state_change(sk);
1463                                 }
1464                         }
1465                 }
1466                 spin_unlock_bh(&iucv->message_q.lock);
1467         }
1468
1469 done:
1470         /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1471         if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1472                 copied = rlen;
1473
1474         return copied;
1475 }
1476
1477 static inline __poll_t iucv_accept_poll(struct sock *parent)
1478 {
1479         struct iucv_sock *isk, *n;
1480         struct sock *sk;
1481
1482         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1483                 sk = (struct sock *) isk;
1484
1485                 if (sk->sk_state == IUCV_CONNECTED)
1486                         return POLLIN | POLLRDNORM;
1487         }
1488
1489         return 0;
1490 }
1491
1492 __poll_t iucv_sock_poll(struct file *file, struct socket *sock,
1493                             poll_table *wait)
1494 {
1495         struct sock *sk = sock->sk;
1496         __poll_t mask = 0;
1497
1498         sock_poll_wait(file, sk_sleep(sk), wait);
1499
1500         if (sk->sk_state == IUCV_LISTEN)
1501                 return iucv_accept_poll(sk);
1502
1503         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1504                 mask |= POLLERR |
1505                         (sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? POLLPRI : 0);
1506
1507         if (sk->sk_shutdown & RCV_SHUTDOWN)
1508                 mask |= POLLRDHUP;
1509
1510         if (sk->sk_shutdown == SHUTDOWN_MASK)
1511                 mask |= POLLHUP;
1512
1513         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1514             (sk->sk_shutdown & RCV_SHUTDOWN))
1515                 mask |= POLLIN | POLLRDNORM;
1516
1517         if (sk->sk_state == IUCV_CLOSED)
1518                 mask |= POLLHUP;
1519
1520         if (sk->sk_state == IUCV_DISCONN)
1521                 mask |= POLLIN;
1522
1523         if (sock_writeable(sk) && iucv_below_msglim(sk))
1524                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1525         else
1526                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1527
1528         return mask;
1529 }
1530
1531 static int iucv_sock_shutdown(struct socket *sock, int how)
1532 {
1533         struct sock *sk = sock->sk;
1534         struct iucv_sock *iucv = iucv_sk(sk);
1535         struct iucv_message txmsg;
1536         int err = 0;
1537
1538         how++;
1539
1540         if ((how & ~SHUTDOWN_MASK) || !how)
1541                 return -EINVAL;
1542
1543         lock_sock(sk);
1544         switch (sk->sk_state) {
1545         case IUCV_LISTEN:
1546         case IUCV_DISCONN:
1547         case IUCV_CLOSING:
1548         case IUCV_CLOSED:
1549                 err = -ENOTCONN;
1550                 goto fail;
1551         default:
1552                 break;
1553         }
1554
1555         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1556                 if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1557                         txmsg.class = 0;
1558                         txmsg.tag = 0;
1559                         err = pr_iucv->message_send(iucv->path, &txmsg,
1560                                 IUCV_IPRMDATA, 0, (void *) iprm_shutdown, 8);
1561                         if (err) {
1562                                 switch (err) {
1563                                 case 1:
1564                                         err = -ENOTCONN;
1565                                         break;
1566                                 case 2:
1567                                         err = -ECONNRESET;
1568                                         break;
1569                                 default:
1570                                         err = -ENOTCONN;
1571                                         break;
1572                                 }
1573                         }
1574                 } else
1575                         iucv_send_ctrl(sk, AF_IUCV_FLAG_SHT);
1576         }
1577
1578         sk->sk_shutdown |= how;
1579         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1580                 if ((iucv->transport == AF_IUCV_TRANS_IUCV) &&
1581                     iucv->path) {
1582                         err = pr_iucv->path_quiesce(iucv->path, NULL);
1583                         if (err)
1584                                 err = -ENOTCONN;
1585 /*                      skb_queue_purge(&sk->sk_receive_queue); */
1586                 }
1587                 skb_queue_purge(&sk->sk_receive_queue);
1588         }
1589
1590         /* Wake up anyone sleeping in poll */
1591         sk->sk_state_change(sk);
1592
1593 fail:
1594         release_sock(sk);
1595         return err;
1596 }
1597
1598 static int iucv_sock_release(struct socket *sock)
1599 {
1600         struct sock *sk = sock->sk;
1601         int err = 0;
1602
1603         if (!sk)
1604                 return 0;
1605
1606         iucv_sock_close(sk);
1607
1608         sock_orphan(sk);
1609         iucv_sock_kill(sk);
1610         return err;
1611 }
1612
1613 /* getsockopt and setsockopt */
1614 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1615                                 char __user *optval, unsigned int optlen)
1616 {
1617         struct sock *sk = sock->sk;
1618         struct iucv_sock *iucv = iucv_sk(sk);
1619         int val;
1620         int rc;
1621
1622         if (level != SOL_IUCV)
1623                 return -ENOPROTOOPT;
1624
1625         if (optlen < sizeof(int))
1626                 return -EINVAL;
1627
1628         if (get_user(val, (int __user *) optval))
1629                 return -EFAULT;
1630
1631         rc = 0;
1632
1633         lock_sock(sk);
1634         switch (optname) {
1635         case SO_IPRMDATA_MSG:
1636                 if (val)
1637                         iucv->flags |= IUCV_IPRMDATA;
1638                 else
1639                         iucv->flags &= ~IUCV_IPRMDATA;
1640                 break;
1641         case SO_MSGLIMIT:
1642                 switch (sk->sk_state) {
1643                 case IUCV_OPEN:
1644                 case IUCV_BOUND:
1645                         if (val < 1 || val > (u16)(~0))
1646                                 rc = -EINVAL;
1647                         else
1648                                 iucv->msglimit = val;
1649                         break;
1650                 default:
1651                         rc = -EINVAL;
1652                         break;
1653                 }
1654                 break;
1655         default:
1656                 rc = -ENOPROTOOPT;
1657                 break;
1658         }
1659         release_sock(sk);
1660
1661         return rc;
1662 }
1663
1664 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1665                                 char __user *optval, int __user *optlen)
1666 {
1667         struct sock *sk = sock->sk;
1668         struct iucv_sock *iucv = iucv_sk(sk);
1669         unsigned int val;
1670         int len;
1671
1672         if (level != SOL_IUCV)
1673                 return -ENOPROTOOPT;
1674
1675         if (get_user(len, optlen))
1676                 return -EFAULT;
1677
1678         if (len < 0)
1679                 return -EINVAL;
1680
1681         len = min_t(unsigned int, len, sizeof(int));
1682
1683         switch (optname) {
1684         case SO_IPRMDATA_MSG:
1685                 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1686                 break;
1687         case SO_MSGLIMIT:
1688                 lock_sock(sk);
1689                 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1690                                            : iucv->msglimit;    /* default */
1691                 release_sock(sk);
1692                 break;
1693         case SO_MSGSIZE:
1694                 if (sk->sk_state == IUCV_OPEN)
1695                         return -EBADFD;
1696                 val = (iucv->hs_dev) ? iucv->hs_dev->mtu -
1697                                 sizeof(struct af_iucv_trans_hdr) - ETH_HLEN :
1698                                 0x7fffffff;
1699                 break;
1700         default:
1701                 return -ENOPROTOOPT;
1702         }
1703
1704         if (put_user(len, optlen))
1705                 return -EFAULT;
1706         if (copy_to_user(optval, &val, len))
1707                 return -EFAULT;
1708
1709         return 0;
1710 }
1711
1712
1713 /* Callback wrappers - called from iucv base support */
1714 static int iucv_callback_connreq(struct iucv_path *path,
1715                                  u8 ipvmid[8], u8 ipuser[16])
1716 {
1717         unsigned char user_data[16];
1718         unsigned char nuser_data[16];
1719         unsigned char src_name[8];
1720         struct sock *sk, *nsk;
1721         struct iucv_sock *iucv, *niucv;
1722         int err;
1723
1724         memcpy(src_name, ipuser, 8);
1725         EBCASC(src_name, 8);
1726         /* Find out if this path belongs to af_iucv. */
1727         read_lock(&iucv_sk_list.lock);
1728         iucv = NULL;
1729         sk = NULL;
1730         sk_for_each(sk, &iucv_sk_list.head)
1731                 if (sk->sk_state == IUCV_LISTEN &&
1732                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1733                         /*
1734                          * Found a listening socket with
1735                          * src_name == ipuser[0-7].
1736                          */
1737                         iucv = iucv_sk(sk);
1738                         break;
1739                 }
1740         read_unlock(&iucv_sk_list.lock);
1741         if (!iucv)
1742                 /* No socket found, not one of our paths. */
1743                 return -EINVAL;
1744
1745         bh_lock_sock(sk);
1746
1747         /* Check if parent socket is listening */
1748         low_nmcpy(user_data, iucv->src_name);
1749         high_nmcpy(user_data, iucv->dst_name);
1750         ASCEBC(user_data, sizeof(user_data));
1751         if (sk->sk_state != IUCV_LISTEN) {
1752                 err = pr_iucv->path_sever(path, user_data);
1753                 iucv_path_free(path);
1754                 goto fail;
1755         }
1756
1757         /* Check for backlog size */
1758         if (sk_acceptq_is_full(sk)) {
1759                 err = pr_iucv->path_sever(path, user_data);
1760                 iucv_path_free(path);
1761                 goto fail;
1762         }
1763
1764         /* Create the new socket */
1765         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC, 0);
1766         if (!nsk) {
1767                 err = pr_iucv->path_sever(path, user_data);
1768                 iucv_path_free(path);
1769                 goto fail;
1770         }
1771
1772         niucv = iucv_sk(nsk);
1773         iucv_sock_init(nsk, sk);
1774
1775         /* Set the new iucv_sock */
1776         memcpy(niucv->dst_name, ipuser + 8, 8);
1777         EBCASC(niucv->dst_name, 8);
1778         memcpy(niucv->dst_user_id, ipvmid, 8);
1779         memcpy(niucv->src_name, iucv->src_name, 8);
1780         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1781         niucv->path = path;
1782
1783         /* Call iucv_accept */
1784         high_nmcpy(nuser_data, ipuser + 8);
1785         memcpy(nuser_data + 8, niucv->src_name, 8);
1786         ASCEBC(nuser_data + 8, 8);
1787
1788         /* set message limit for path based on msglimit of accepting socket */
1789         niucv->msglimit = iucv->msglimit;
1790         path->msglim = iucv->msglimit;
1791         err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1792         if (err) {
1793                 iucv_sever_path(nsk, 1);
1794                 iucv_sock_kill(nsk);
1795                 goto fail;
1796         }
1797
1798         iucv_accept_enqueue(sk, nsk);
1799
1800         /* Wake up accept */
1801         nsk->sk_state = IUCV_CONNECTED;
1802         sk->sk_data_ready(sk);
1803         err = 0;
1804 fail:
1805         bh_unlock_sock(sk);
1806         return 0;
1807 }
1808
1809 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1810 {
1811         struct sock *sk = path->private;
1812
1813         sk->sk_state = IUCV_CONNECTED;
1814         sk->sk_state_change(sk);
1815 }
1816
1817 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1818 {
1819         struct sock *sk = path->private;
1820         struct iucv_sock *iucv = iucv_sk(sk);
1821         struct sk_buff *skb;
1822         struct sock_msg_q *save_msg;
1823         int len;
1824
1825         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1826                 pr_iucv->message_reject(path, msg);
1827                 return;
1828         }
1829
1830         spin_lock(&iucv->message_q.lock);
1831
1832         if (!list_empty(&iucv->message_q.list) ||
1833             !skb_queue_empty(&iucv->backlog_skb_q))
1834                 goto save_message;
1835
1836         len = atomic_read(&sk->sk_rmem_alloc);
1837         len += SKB_TRUESIZE(iucv_msg_length(msg));
1838         if (len > sk->sk_rcvbuf)
1839                 goto save_message;
1840
1841         skb = alloc_iucv_recv_skb(iucv_msg_length(msg));
1842         if (!skb)
1843                 goto save_message;
1844
1845         iucv_process_message(sk, skb, path, msg);
1846         goto out_unlock;
1847
1848 save_message:
1849         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1850         if (!save_msg)
1851                 goto out_unlock;
1852         save_msg->path = path;
1853         save_msg->msg = *msg;
1854
1855         list_add_tail(&save_msg->list, &iucv->message_q.list);
1856
1857 out_unlock:
1858         spin_unlock(&iucv->message_q.lock);
1859 }
1860
1861 static void iucv_callback_txdone(struct iucv_path *path,
1862                                  struct iucv_message *msg)
1863 {
1864         struct sock *sk = path->private;
1865         struct sk_buff *this = NULL;
1866         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1867         struct sk_buff *list_skb = list->next;
1868         unsigned long flags;
1869
1870         bh_lock_sock(sk);
1871         if (!skb_queue_empty(list)) {
1872                 spin_lock_irqsave(&list->lock, flags);
1873
1874                 while (list_skb != (struct sk_buff *)list) {
1875                         if (msg->tag == IUCV_SKB_CB(list_skb)->tag) {
1876                                 this = list_skb;
1877                                 break;
1878                         }
1879                         list_skb = list_skb->next;
1880                 }
1881                 if (this)
1882                         __skb_unlink(this, list);
1883
1884                 spin_unlock_irqrestore(&list->lock, flags);
1885
1886                 if (this) {
1887                         kfree_skb(this);
1888                         /* wake up any process waiting for sending */
1889                         iucv_sock_wake_msglim(sk);
1890                 }
1891         }
1892
1893         if (sk->sk_state == IUCV_CLOSING) {
1894                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1895                         sk->sk_state = IUCV_CLOSED;
1896                         sk->sk_state_change(sk);
1897                 }
1898         }
1899         bh_unlock_sock(sk);
1900
1901 }
1902
1903 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1904 {
1905         struct sock *sk = path->private;
1906
1907         if (sk->sk_state == IUCV_CLOSED)
1908                 return;
1909
1910         bh_lock_sock(sk);
1911         iucv_sever_path(sk, 1);
1912         sk->sk_state = IUCV_DISCONN;
1913
1914         sk->sk_state_change(sk);
1915         bh_unlock_sock(sk);
1916 }
1917
1918 /* called if the other communication side shuts down its RECV direction;
1919  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1920  */
1921 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1922 {
1923         struct sock *sk = path->private;
1924
1925         bh_lock_sock(sk);
1926         if (sk->sk_state != IUCV_CLOSED) {
1927                 sk->sk_shutdown |= SEND_SHUTDOWN;
1928                 sk->sk_state_change(sk);
1929         }
1930         bh_unlock_sock(sk);
1931 }
1932
1933 /***************** HiperSockets transport callbacks ********************/
1934 static void afiucv_swap_src_dest(struct sk_buff *skb)
1935 {
1936         struct af_iucv_trans_hdr *trans_hdr =
1937                                 (struct af_iucv_trans_hdr *)skb->data;
1938         char tmpID[8];
1939         char tmpName[8];
1940
1941         ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1942         ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1943         ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1944         ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1945         memcpy(tmpID, trans_hdr->srcUserID, 8);
1946         memcpy(tmpName, trans_hdr->srcAppName, 8);
1947         memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1948         memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1949         memcpy(trans_hdr->destUserID, tmpID, 8);
1950         memcpy(trans_hdr->destAppName, tmpName, 8);
1951         skb_push(skb, ETH_HLEN);
1952         memset(skb->data, 0, ETH_HLEN);
1953 }
1954
1955 /**
1956  * afiucv_hs_callback_syn - react on received SYN
1957  **/
1958 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1959 {
1960         struct sock *nsk;
1961         struct iucv_sock *iucv, *niucv;
1962         struct af_iucv_trans_hdr *trans_hdr;
1963         int err;
1964
1965         iucv = iucv_sk(sk);
1966         trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
1967         if (!iucv) {
1968                 /* no sock - connection refused */
1969                 afiucv_swap_src_dest(skb);
1970                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1971                 err = dev_queue_xmit(skb);
1972                 goto out;
1973         }
1974
1975         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC, 0);
1976         bh_lock_sock(sk);
1977         if ((sk->sk_state != IUCV_LISTEN) ||
1978             sk_acceptq_is_full(sk) ||
1979             !nsk) {
1980                 /* error on server socket - connection refused */
1981                 afiucv_swap_src_dest(skb);
1982                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1983                 err = dev_queue_xmit(skb);
1984                 iucv_sock_kill(nsk);
1985                 bh_unlock_sock(sk);
1986                 goto out;
1987         }
1988
1989         niucv = iucv_sk(nsk);
1990         iucv_sock_init(nsk, sk);
1991         niucv->transport = AF_IUCV_TRANS_HIPER;
1992         niucv->msglimit = iucv->msglimit;
1993         if (!trans_hdr->window)
1994                 niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
1995         else
1996                 niucv->msglimit_peer = trans_hdr->window;
1997         memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
1998         memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
1999         memcpy(niucv->src_name, iucv->src_name, 8);
2000         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
2001         nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
2002         niucv->hs_dev = iucv->hs_dev;
2003         dev_hold(niucv->hs_dev);
2004         afiucv_swap_src_dest(skb);
2005         trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
2006         trans_hdr->window = niucv->msglimit;
2007         /* if receiver acks the xmit connection is established */
2008         err = dev_queue_xmit(skb);
2009         if (!err) {
2010                 iucv_accept_enqueue(sk, nsk);
2011                 nsk->sk_state = IUCV_CONNECTED;
2012                 sk->sk_data_ready(sk);
2013         } else
2014                 iucv_sock_kill(nsk);
2015         bh_unlock_sock(sk);
2016
2017 out:
2018         return NET_RX_SUCCESS;
2019 }
2020
2021 /**
2022  * afiucv_hs_callback_synack() - react on received SYN-ACK
2023  **/
2024 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
2025 {
2026         struct iucv_sock *iucv = iucv_sk(sk);
2027         struct af_iucv_trans_hdr *trans_hdr =
2028                                         (struct af_iucv_trans_hdr *)skb->data;
2029
2030         if (!iucv)
2031                 goto out;
2032         if (sk->sk_state != IUCV_BOUND)
2033                 goto out;
2034         bh_lock_sock(sk);
2035         iucv->msglimit_peer = trans_hdr->window;
2036         sk->sk_state = IUCV_CONNECTED;
2037         sk->sk_state_change(sk);
2038         bh_unlock_sock(sk);
2039 out:
2040         kfree_skb(skb);
2041         return NET_RX_SUCCESS;
2042 }
2043
2044 /**
2045  * afiucv_hs_callback_synfin() - react on received SYN_FIN
2046  **/
2047 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
2048 {
2049         struct iucv_sock *iucv = iucv_sk(sk);
2050
2051         if (!iucv)
2052                 goto out;
2053         if (sk->sk_state != IUCV_BOUND)
2054                 goto out;
2055         bh_lock_sock(sk);
2056         sk->sk_state = IUCV_DISCONN;
2057         sk->sk_state_change(sk);
2058         bh_unlock_sock(sk);
2059 out:
2060         kfree_skb(skb);
2061         return NET_RX_SUCCESS;
2062 }
2063
2064 /**
2065  * afiucv_hs_callback_fin() - react on received FIN
2066  **/
2067 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
2068 {
2069         struct iucv_sock *iucv = iucv_sk(sk);
2070
2071         /* other end of connection closed */
2072         if (!iucv)
2073                 goto out;
2074         bh_lock_sock(sk);
2075         if (sk->sk_state == IUCV_CONNECTED) {
2076                 sk->sk_state = IUCV_DISCONN;
2077                 sk->sk_state_change(sk);
2078         }
2079         bh_unlock_sock(sk);
2080 out:
2081         kfree_skb(skb);
2082         return NET_RX_SUCCESS;
2083 }
2084
2085 /**
2086  * afiucv_hs_callback_win() - react on received WIN
2087  **/
2088 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
2089 {
2090         struct iucv_sock *iucv = iucv_sk(sk);
2091         struct af_iucv_trans_hdr *trans_hdr =
2092                                         (struct af_iucv_trans_hdr *)skb->data;
2093
2094         if (!iucv)
2095                 return NET_RX_SUCCESS;
2096
2097         if (sk->sk_state != IUCV_CONNECTED)
2098                 return NET_RX_SUCCESS;
2099
2100         atomic_sub(trans_hdr->window, &iucv->msg_sent);
2101         iucv_sock_wake_msglim(sk);
2102         return NET_RX_SUCCESS;
2103 }
2104
2105 /**
2106  * afiucv_hs_callback_rx() - react on received data
2107  **/
2108 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
2109 {
2110         struct iucv_sock *iucv = iucv_sk(sk);
2111
2112         if (!iucv) {
2113                 kfree_skb(skb);
2114                 return NET_RX_SUCCESS;
2115         }
2116
2117         if (sk->sk_state != IUCV_CONNECTED) {
2118                 kfree_skb(skb);
2119                 return NET_RX_SUCCESS;
2120         }
2121
2122         if (sk->sk_shutdown & RCV_SHUTDOWN) {
2123                 kfree_skb(skb);
2124                 return NET_RX_SUCCESS;
2125         }
2126
2127         /* write stuff from iucv_msg to skb cb */
2128         skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2129         skb_reset_transport_header(skb);
2130         skb_reset_network_header(skb);
2131         IUCV_SKB_CB(skb)->offset = 0;
2132         if (sk_filter(sk, skb)) {
2133                 atomic_inc(&sk->sk_drops);      /* skb rejected by filter */
2134                 kfree_skb(skb);
2135                 return NET_RX_SUCCESS;
2136         }
2137
2138         spin_lock(&iucv->message_q.lock);
2139         if (skb_queue_empty(&iucv->backlog_skb_q)) {
2140                 if (__sock_queue_rcv_skb(sk, skb))
2141                         /* handle rcv queue full */
2142                         skb_queue_tail(&iucv->backlog_skb_q, skb);
2143         } else
2144                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2145         spin_unlock(&iucv->message_q.lock);
2146         return NET_RX_SUCCESS;
2147 }
2148
2149 /**
2150  * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2151  *                   transport
2152  *                   called from netif RX softirq
2153  **/
2154 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2155         struct packet_type *pt, struct net_device *orig_dev)
2156 {
2157         struct sock *sk;
2158         struct iucv_sock *iucv;
2159         struct af_iucv_trans_hdr *trans_hdr;
2160         char nullstring[8];
2161         int err = 0;
2162
2163         if (skb->len < (ETH_HLEN + sizeof(struct af_iucv_trans_hdr))) {
2164                 WARN_ONCE(1, "AF_IUCV too short skb, len=%d, min=%d",
2165                           (int)skb->len,
2166                           (int)(ETH_HLEN + sizeof(struct af_iucv_trans_hdr)));
2167                 kfree_skb(skb);
2168                 return NET_RX_SUCCESS;
2169         }
2170         if (skb_headlen(skb) < (ETH_HLEN + sizeof(struct af_iucv_trans_hdr)))
2171                 if (skb_linearize(skb)) {
2172                         WARN_ONCE(1, "AF_IUCV skb_linearize failed, len=%d",
2173                                   (int)skb->len);
2174                         kfree_skb(skb);
2175                         return NET_RX_SUCCESS;
2176                 }
2177         skb_pull(skb, ETH_HLEN);
2178         trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
2179         EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2180         EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2181         EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2182         EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2183         memset(nullstring, 0, sizeof(nullstring));
2184         iucv = NULL;
2185         sk = NULL;
2186         read_lock(&iucv_sk_list.lock);
2187         sk_for_each(sk, &iucv_sk_list.head) {
2188                 if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2189                         if ((!memcmp(&iucv_sk(sk)->src_name,
2190                                      trans_hdr->destAppName, 8)) &&
2191                             (!memcmp(&iucv_sk(sk)->src_user_id,
2192                                      trans_hdr->destUserID, 8)) &&
2193                             (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2194                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2195                                      nullstring, 8))) {
2196                                 iucv = iucv_sk(sk);
2197                                 break;
2198                         }
2199                 } else {
2200                         if ((!memcmp(&iucv_sk(sk)->src_name,
2201                                      trans_hdr->destAppName, 8)) &&
2202                             (!memcmp(&iucv_sk(sk)->src_user_id,
2203                                      trans_hdr->destUserID, 8)) &&
2204                             (!memcmp(&iucv_sk(sk)->dst_name,
2205                                      trans_hdr->srcAppName, 8)) &&
2206                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2207                                      trans_hdr->srcUserID, 8))) {
2208                                 iucv = iucv_sk(sk);
2209                                 break;
2210                         }
2211                 }
2212         }
2213         read_unlock(&iucv_sk_list.lock);
2214         if (!iucv)
2215                 sk = NULL;
2216
2217         /* no sock
2218         how should we send with no sock
2219         1) send without sock no send rc checking?
2220         2) introduce default sock to handle this cases
2221
2222          SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2223          data -> send FIN
2224          SYN|ACK, SYN|FIN, FIN -> no action? */
2225
2226         switch (trans_hdr->flags) {
2227         case AF_IUCV_FLAG_SYN:
2228                 /* connect request */
2229                 err = afiucv_hs_callback_syn(sk, skb);
2230                 break;
2231         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2232                 /* connect request confirmed */
2233                 err = afiucv_hs_callback_synack(sk, skb);
2234                 break;
2235         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2236                 /* connect request refused */
2237                 err = afiucv_hs_callback_synfin(sk, skb);
2238                 break;
2239         case (AF_IUCV_FLAG_FIN):
2240                 /* close request */
2241                 err = afiucv_hs_callback_fin(sk, skb);
2242                 break;
2243         case (AF_IUCV_FLAG_WIN):
2244                 err = afiucv_hs_callback_win(sk, skb);
2245                 if (skb->len == sizeof(struct af_iucv_trans_hdr)) {
2246                         kfree_skb(skb);
2247                         break;
2248                 }
2249                 /* fall through and receive non-zero length data */
2250         case (AF_IUCV_FLAG_SHT):
2251                 /* shutdown request */
2252                 /* fall through and receive zero length data */
2253         case 0:
2254                 /* plain data frame */
2255                 IUCV_SKB_CB(skb)->class = trans_hdr->iucv_hdr.class;
2256                 err = afiucv_hs_callback_rx(sk, skb);
2257                 break;
2258         default:
2259                 ;
2260         }
2261
2262         return err;
2263 }
2264
2265 /**
2266  * afiucv_hs_callback_txnotify() - handle send notifcations from HiperSockets
2267  *                                 transport
2268  **/
2269 static void afiucv_hs_callback_txnotify(struct sk_buff *skb,
2270                                         enum iucv_tx_notify n)
2271 {
2272         struct sock *isk = skb->sk;
2273         struct sock *sk = NULL;
2274         struct iucv_sock *iucv = NULL;
2275         struct sk_buff_head *list;
2276         struct sk_buff *list_skb;
2277         struct sk_buff *nskb;
2278         unsigned long flags;
2279
2280         read_lock_irqsave(&iucv_sk_list.lock, flags);
2281         sk_for_each(sk, &iucv_sk_list.head)
2282                 if (sk == isk) {
2283                         iucv = iucv_sk(sk);
2284                         break;
2285                 }
2286         read_unlock_irqrestore(&iucv_sk_list.lock, flags);
2287
2288         if (!iucv || sock_flag(sk, SOCK_ZAPPED))
2289                 return;
2290
2291         list = &iucv->send_skb_q;
2292         spin_lock_irqsave(&list->lock, flags);
2293         if (skb_queue_empty(list))
2294                 goto out_unlock;
2295         list_skb = list->next;
2296         nskb = list_skb->next;
2297         while (list_skb != (struct sk_buff *)list) {
2298                 if (skb_shinfo(list_skb) == skb_shinfo(skb)) {
2299                         switch (n) {
2300                         case TX_NOTIFY_OK:
2301                                 __skb_unlink(list_skb, list);
2302                                 kfree_skb(list_skb);
2303                                 iucv_sock_wake_msglim(sk);
2304                                 break;
2305                         case TX_NOTIFY_PENDING:
2306                                 atomic_inc(&iucv->pendings);
2307                                 break;
2308                         case TX_NOTIFY_DELAYED_OK:
2309                                 __skb_unlink(list_skb, list);
2310                                 atomic_dec(&iucv->pendings);
2311                                 if (atomic_read(&iucv->pendings) <= 0)
2312                                         iucv_sock_wake_msglim(sk);
2313                                 kfree_skb(list_skb);
2314                                 break;
2315                         case TX_NOTIFY_UNREACHABLE:
2316                         case TX_NOTIFY_DELAYED_UNREACHABLE:
2317                         case TX_NOTIFY_TPQFULL: /* not yet used */
2318                         case TX_NOTIFY_GENERALERROR:
2319                         case TX_NOTIFY_DELAYED_GENERALERROR:
2320                                 __skb_unlink(list_skb, list);
2321                                 kfree_skb(list_skb);
2322                                 if (sk->sk_state == IUCV_CONNECTED) {
2323                                         sk->sk_state = IUCV_DISCONN;
2324                                         sk->sk_state_change(sk);
2325                                 }
2326                                 break;
2327                         }
2328                         break;
2329                 }
2330                 list_skb = nskb;
2331                 nskb = nskb->next;
2332         }
2333 out_unlock:
2334         spin_unlock_irqrestore(&list->lock, flags);
2335
2336         if (sk->sk_state == IUCV_CLOSING) {
2337                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
2338                         sk->sk_state = IUCV_CLOSED;
2339                         sk->sk_state_change(sk);
2340                 }
2341         }
2342
2343 }
2344
2345 /*
2346  * afiucv_netdev_event: handle netdev notifier chain events
2347  */
2348 static int afiucv_netdev_event(struct notifier_block *this,
2349                                unsigned long event, void *ptr)
2350 {
2351         struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2352         struct sock *sk;
2353         struct iucv_sock *iucv;
2354
2355         switch (event) {
2356         case NETDEV_REBOOT:
2357         case NETDEV_GOING_DOWN:
2358                 sk_for_each(sk, &iucv_sk_list.head) {
2359                         iucv = iucv_sk(sk);
2360                         if ((iucv->hs_dev == event_dev) &&
2361                             (sk->sk_state == IUCV_CONNECTED)) {
2362                                 if (event == NETDEV_GOING_DOWN)
2363                                         iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
2364                                 sk->sk_state = IUCV_DISCONN;
2365                                 sk->sk_state_change(sk);
2366                         }
2367                 }
2368                 break;
2369         case NETDEV_DOWN:
2370         case NETDEV_UNREGISTER:
2371         default:
2372                 break;
2373         }
2374         return NOTIFY_DONE;
2375 }
2376
2377 static struct notifier_block afiucv_netdev_notifier = {
2378         .notifier_call = afiucv_netdev_event,
2379 };
2380
2381 static const struct proto_ops iucv_sock_ops = {
2382         .family         = PF_IUCV,
2383         .owner          = THIS_MODULE,
2384         .release        = iucv_sock_release,
2385         .bind           = iucv_sock_bind,
2386         .connect        = iucv_sock_connect,
2387         .listen         = iucv_sock_listen,
2388         .accept         = iucv_sock_accept,
2389         .getname        = iucv_sock_getname,
2390         .sendmsg        = iucv_sock_sendmsg,
2391         .recvmsg        = iucv_sock_recvmsg,
2392         .poll           = iucv_sock_poll,
2393         .ioctl          = sock_no_ioctl,
2394         .mmap           = sock_no_mmap,
2395         .socketpair     = sock_no_socketpair,
2396         .shutdown       = iucv_sock_shutdown,
2397         .setsockopt     = iucv_sock_setsockopt,
2398         .getsockopt     = iucv_sock_getsockopt,
2399 };
2400
2401 static const struct net_proto_family iucv_sock_family_ops = {
2402         .family = AF_IUCV,
2403         .owner  = THIS_MODULE,
2404         .create = iucv_sock_create,
2405 };
2406
2407 static struct packet_type iucv_packet_type = {
2408         .type = cpu_to_be16(ETH_P_AF_IUCV),
2409         .func = afiucv_hs_rcv,
2410 };
2411
2412 static int afiucv_iucv_init(void)
2413 {
2414         int err;
2415
2416         err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2417         if (err)
2418                 goto out;
2419         /* establish dummy device */
2420         af_iucv_driver.bus = pr_iucv->bus;
2421         err = driver_register(&af_iucv_driver);
2422         if (err)
2423                 goto out_iucv;
2424         af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2425         if (!af_iucv_dev) {
2426                 err = -ENOMEM;
2427                 goto out_driver;
2428         }
2429         dev_set_name(af_iucv_dev, "af_iucv");
2430         af_iucv_dev->bus = pr_iucv->bus;
2431         af_iucv_dev->parent = pr_iucv->root;
2432         af_iucv_dev->release = (void (*)(struct device *))kfree;
2433         af_iucv_dev->driver = &af_iucv_driver;
2434         err = device_register(af_iucv_dev);
2435         if (err)
2436                 goto out_driver;
2437         return 0;
2438
2439 out_driver:
2440         driver_unregister(&af_iucv_driver);
2441 out_iucv:
2442         pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2443 out:
2444         return err;
2445 }
2446
2447 static int __init afiucv_init(void)
2448 {
2449         int err;
2450
2451         if (MACHINE_IS_VM) {
2452                 cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2453                 if (unlikely(err)) {
2454                         WARN_ON(err);
2455                         err = -EPROTONOSUPPORT;
2456                         goto out;
2457                 }
2458
2459                 pr_iucv = try_then_request_module(symbol_get(iucv_if), "iucv");
2460                 if (!pr_iucv) {
2461                         printk(KERN_WARNING "iucv_if lookup failed\n");
2462                         memset(&iucv_userid, 0, sizeof(iucv_userid));
2463                 }
2464         } else {
2465                 memset(&iucv_userid, 0, sizeof(iucv_userid));
2466                 pr_iucv = NULL;
2467         }
2468
2469         err = proto_register(&iucv_proto, 0);
2470         if (err)
2471                 goto out;
2472         err = sock_register(&iucv_sock_family_ops);
2473         if (err)
2474                 goto out_proto;
2475
2476         if (pr_iucv) {
2477                 err = afiucv_iucv_init();
2478                 if (err)
2479                         goto out_sock;
2480         } else
2481                 register_netdevice_notifier(&afiucv_netdev_notifier);
2482         dev_add_pack(&iucv_packet_type);
2483         return 0;
2484
2485 out_sock:
2486         sock_unregister(PF_IUCV);
2487 out_proto:
2488         proto_unregister(&iucv_proto);
2489 out:
2490         if (pr_iucv)
2491                 symbol_put(iucv_if);
2492         return err;
2493 }
2494
2495 static void __exit afiucv_exit(void)
2496 {
2497         if (pr_iucv) {
2498                 device_unregister(af_iucv_dev);
2499                 driver_unregister(&af_iucv_driver);
2500                 pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2501                 symbol_put(iucv_if);
2502         } else
2503                 unregister_netdevice_notifier(&afiucv_netdev_notifier);
2504         dev_remove_pack(&iucv_packet_type);
2505         sock_unregister(PF_IUCV);
2506         proto_unregister(&iucv_proto);
2507 }
2508
2509 module_init(afiucv_init);
2510 module_exit(afiucv_exit);
2511
2512 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2513 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2514 MODULE_VERSION(VERSION);
2515 MODULE_LICENSE("GPL");
2516 MODULE_ALIAS_NETPROTO(PF_IUCV);
2517