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TOMOYO Linux Cross Reference
Linux/net/iucv/af_iucv.c

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  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.h>
 21 #include <linux/slab.h>
 22 #include <linux/skbuff.h>
 23 #include <linux/init.h>
 24 #include <linux/poll.h>
 25 #include <net/sock.h>
 26 #include <asm/ebcdic.h>
 27 #include <asm/cpcmd.h>
 28 #include <linux/kmod.h>
 29 
 30 #include <net/iucv/iucv.h>
 31 #include <net/iucv/af_iucv.h>
 32 
 33 #define VERSION "1.1"
 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 /* special AF_IUCV IPRM messages */
 46 static const u8 iprm_shutdown[8] =
 47         {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
 48 
 49 #define TRGCLS_SIZE     (sizeof(((struct iucv_message *)0)->class))
 50 
 51 /* macros to set/get socket control buffer at correct offset */
 52 #define CB_TAG(skb)     ((skb)->cb)             /* iucv message tag */
 53 #define CB_TAG_LEN      (sizeof(((struct iucv_message *) 0)->tag))
 54 #define CB_TRGCLS(skb)  ((skb)->cb + CB_TAG_LEN) /* iucv msg target class */
 55 #define CB_TRGCLS_LEN   (TRGCLS_SIZE)
 56 
 57 #define __iucv_sock_wait(sk, condition, timeo, ret)                     \
 58 do {                                                                    \
 59         DEFINE_WAIT(__wait);                                            \
 60         long __timeo = timeo;                                           \
 61         ret = 0;                                                        \
 62         prepare_to_wait(sk_sleep(sk), &__wait, TASK_INTERRUPTIBLE);     \
 63         while (!(condition)) {                                          \
 64                 if (!__timeo) {                                         \
 65                         ret = -EAGAIN;                                  \
 66                         break;                                          \
 67                 }                                                       \
 68                 if (signal_pending(current)) {                          \
 69                         ret = sock_intr_errno(__timeo);                 \
 70                         break;                                          \
 71                 }                                                       \
 72                 release_sock(sk);                                       \
 73                 __timeo = schedule_timeout(__timeo);                    \
 74                 lock_sock(sk);                                          \
 75                 ret = sock_error(sk);                                   \
 76                 if (ret)                                                \
 77                         break;                                          \
 78         }                                                               \
 79         finish_wait(sk_sleep(sk), &__wait);                             \
 80 } while (0)
 81 
 82 #define iucv_sock_wait(sk, condition, timeo)                            \
 83 ({                                                                      \
 84         int __ret = 0;                                                  \
 85         if (!(condition))                                               \
 86                 __iucv_sock_wait(sk, condition, timeo, __ret);          \
 87         __ret;                                                          \
 88 })
 89 
 90 static void iucv_sock_kill(struct sock *sk);
 91 static void iucv_sock_close(struct sock *sk);
 92 
 93 /* Call Back functions */
 94 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
 95 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
 96 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
 97 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
 98                                  u8 ipuser[16]);
 99 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
100 static void iucv_callback_shutdown(struct iucv_path *, u8 ipuser[16]);
101 
102 static struct iucv_sock_list iucv_sk_list = {
103         .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
104         .autobind_name = ATOMIC_INIT(0)
105 };
106 
107 static struct iucv_handler af_iucv_handler = {
108         .path_pending     = iucv_callback_connreq,
109         .path_complete    = iucv_callback_connack,
110         .path_severed     = iucv_callback_connrej,
111         .message_pending  = iucv_callback_rx,
112         .message_complete = iucv_callback_txdone,
113         .path_quiesced    = iucv_callback_shutdown,
114 };
115 
116 static inline void high_nmcpy(unsigned char *dst, char *src)
117 {
118        memcpy(dst, src, 8);
119 }
120 
121 static inline void low_nmcpy(unsigned char *dst, char *src)
122 {
123        memcpy(&dst[8], src, 8);
124 }
125 
126 static int afiucv_pm_prepare(struct device *dev)
127 {
128 #ifdef CONFIG_PM_DEBUG
129         printk(KERN_WARNING "afiucv_pm_prepare\n");
130 #endif
131         return 0;
132 }
133 
134 static void afiucv_pm_complete(struct device *dev)
135 {
136 #ifdef CONFIG_PM_DEBUG
137         printk(KERN_WARNING "afiucv_pm_complete\n");
138 #endif
139 }
140 
141 /**
142  * afiucv_pm_freeze() - Freeze PM callback
143  * @dev:        AFIUCV dummy device
144  *
145  * Sever all established IUCV communication pathes
146  */
147 static int afiucv_pm_freeze(struct device *dev)
148 {
149         struct iucv_sock *iucv;
150         struct sock *sk;
151         struct hlist_node *node;
152         int err = 0;
153 
154 #ifdef CONFIG_PM_DEBUG
155         printk(KERN_WARNING "afiucv_pm_freeze\n");
156 #endif
157         read_lock(&iucv_sk_list.lock);
158         sk_for_each(sk, node, &iucv_sk_list.head) {
159                 iucv = iucv_sk(sk);
160                 skb_queue_purge(&iucv->send_skb_q);
161                 skb_queue_purge(&iucv->backlog_skb_q);
162                 switch (sk->sk_state) {
163                 case IUCV_SEVERED:
164                 case IUCV_DISCONN:
165                 case IUCV_CLOSING:
166                 case IUCV_CONNECTED:
167                         if (iucv->path) {
168                                 err = iucv_path_sever(iucv->path, NULL);
169                                 iucv_path_free(iucv->path);
170                                 iucv->path = NULL;
171                         }
172                         break;
173                 case IUCV_OPEN:
174                 case IUCV_BOUND:
175                 case IUCV_LISTEN:
176                 case IUCV_CLOSED:
177                 default:
178                         break;
179                 }
180         }
181         read_unlock(&iucv_sk_list.lock);
182         return err;
183 }
184 
185 /**
186  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
187  * @dev:        AFIUCV dummy device
188  *
189  * socket clean up after freeze
190  */
191 static int afiucv_pm_restore_thaw(struct device *dev)
192 {
193         struct iucv_sock *iucv;
194         struct sock *sk;
195         struct hlist_node *node;
196 
197 #ifdef CONFIG_PM_DEBUG
198         printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
199 #endif
200         read_lock(&iucv_sk_list.lock);
201         sk_for_each(sk, node, &iucv_sk_list.head) {
202                 iucv = iucv_sk(sk);
203                 switch (sk->sk_state) {
204                 case IUCV_CONNECTED:
205                         sk->sk_err = EPIPE;
206                         sk->sk_state = IUCV_DISCONN;
207                         sk->sk_state_change(sk);
208                         break;
209                 case IUCV_DISCONN:
210                 case IUCV_SEVERED:
211                 case IUCV_CLOSING:
212                 case IUCV_LISTEN:
213                 case IUCV_BOUND:
214                 case IUCV_OPEN:
215                 default:
216                         break;
217                 }
218         }
219         read_unlock(&iucv_sk_list.lock);
220         return 0;
221 }
222 
223 static const struct dev_pm_ops afiucv_pm_ops = {
224         .prepare = afiucv_pm_prepare,
225         .complete = afiucv_pm_complete,
226         .freeze = afiucv_pm_freeze,
227         .thaw = afiucv_pm_restore_thaw,
228         .restore = afiucv_pm_restore_thaw,
229 };
230 
231 static struct device_driver af_iucv_driver = {
232         .owner = THIS_MODULE,
233         .name = "afiucv",
234         .bus  = &iucv_bus,
235         .pm   = &afiucv_pm_ops,
236 };
237 
238 /* dummy device used as trigger for PM functions */
239 static struct device *af_iucv_dev;
240 
241 /**
242  * iucv_msg_length() - Returns the length of an iucv message.
243  * @msg:        Pointer to struct iucv_message, MUST NOT be NULL
244  *
245  * The function returns the length of the specified iucv message @msg of data
246  * stored in a buffer and of data stored in the parameter list (PRMDATA).
247  *
248  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
249  * data:
250  *      PRMDATA[0..6]   socket data (max 7 bytes);
251  *      PRMDATA[7]      socket data length value (len is 0xff - PRMDATA[7])
252  *
253  * The socket data length is computed by substracting the socket data length
254  * value from 0xFF.
255  * If the socket data len is greater 7, then PRMDATA can be used for special
256  * notifications (see iucv_sock_shutdown); and further,
257  * if the socket data len is > 7, the function returns 8.
258  *
259  * Use this function to allocate socket buffers to store iucv message data.
260  */
261 static inline size_t iucv_msg_length(struct iucv_message *msg)
262 {
263         size_t datalen;
264 
265         if (msg->flags & IUCV_IPRMDATA) {
266                 datalen = 0xff - msg->rmmsg[7];
267                 return (datalen < 8) ? datalen : 8;
268         }
269         return msg->length;
270 }
271 
272 /**
273  * iucv_sock_in_state() - check for specific states
274  * @sk:         sock structure
275  * @state:      first iucv sk state
276  * @state:      second iucv sk state
277  *
278  * Returns true if the socket in either in the first or second state.
279  */
280 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
281 {
282         return (sk->sk_state == state || sk->sk_state == state2);
283 }
284 
285 /**
286  * iucv_below_msglim() - function to check if messages can be sent
287  * @sk:         sock structure
288  *
289  * Returns true if the send queue length is lower than the message limit.
290  * Always returns true if the socket is not connected (no iucv path for
291  * checking the message limit).
292  */
293 static inline int iucv_below_msglim(struct sock *sk)
294 {
295         struct iucv_sock *iucv = iucv_sk(sk);
296 
297         if (sk->sk_state != IUCV_CONNECTED)
298                 return 1;
299         return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
300 }
301 
302 /**
303  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
304  */
305 static void iucv_sock_wake_msglim(struct sock *sk)
306 {
307         struct socket_wq *wq;
308 
309         rcu_read_lock();
310         wq = rcu_dereference(sk->sk_wq);
311         if (wq_has_sleeper(wq))
312                 wake_up_interruptible_all(&wq->wait);
313         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
314         rcu_read_unlock();
315 }
316 
317 /* Timers */
318 static void iucv_sock_timeout(unsigned long arg)
319 {
320         struct sock *sk = (struct sock *)arg;
321 
322         bh_lock_sock(sk);
323         sk->sk_err = ETIMEDOUT;
324         sk->sk_state_change(sk);
325         bh_unlock_sock(sk);
326 
327         iucv_sock_kill(sk);
328         sock_put(sk);
329 }
330 
331 static void iucv_sock_clear_timer(struct sock *sk)
332 {
333         sk_stop_timer(sk, &sk->sk_timer);
334 }
335 
336 static struct sock *__iucv_get_sock_by_name(char *nm)
337 {
338         struct sock *sk;
339         struct hlist_node *node;
340 
341         sk_for_each(sk, node, &iucv_sk_list.head)
342                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
343                         return sk;
344 
345         return NULL;
346 }
347 
348 static void iucv_sock_destruct(struct sock *sk)
349 {
350         skb_queue_purge(&sk->sk_receive_queue);
351         skb_queue_purge(&sk->sk_write_queue);
352 }
353 
354 /* Cleanup Listen */
355 static void iucv_sock_cleanup_listen(struct sock *parent)
356 {
357         struct sock *sk;
358 
359         /* Close non-accepted connections */
360         while ((sk = iucv_accept_dequeue(parent, NULL))) {
361                 iucv_sock_close(sk);
362                 iucv_sock_kill(sk);
363         }
364 
365         parent->sk_state = IUCV_CLOSED;
366 }
367 
368 /* Kill socket (only if zapped and orphaned) */
369 static void iucv_sock_kill(struct sock *sk)
370 {
371         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
372                 return;
373 
374         iucv_sock_unlink(&iucv_sk_list, sk);
375         sock_set_flag(sk, SOCK_DEAD);
376         sock_put(sk);
377 }
378 
379 /* Close an IUCV socket */
380 static void iucv_sock_close(struct sock *sk)
381 {
382         unsigned char user_data[16];
383         struct iucv_sock *iucv = iucv_sk(sk);
384         int err;
385         unsigned long timeo;
386 
387         iucv_sock_clear_timer(sk);
388         lock_sock(sk);
389 
390         switch (sk->sk_state) {
391         case IUCV_LISTEN:
392                 iucv_sock_cleanup_listen(sk);
393                 break;
394 
395         case IUCV_CONNECTED:
396         case IUCV_DISCONN:
397                 err = 0;
398 
399                 sk->sk_state = IUCV_CLOSING;
400                 sk->sk_state_change(sk);
401 
402                 if (!skb_queue_empty(&iucv->send_skb_q)) {
403                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
404                                 timeo = sk->sk_lingertime;
405                         else
406                                 timeo = IUCV_DISCONN_TIMEOUT;
407                         err = iucv_sock_wait(sk,
408                                         iucv_sock_in_state(sk, IUCV_CLOSED, 0),
409                                         timeo);
410                 }
411 
412         case IUCV_CLOSING:   /* fall through */
413                 sk->sk_state = IUCV_CLOSED;
414                 sk->sk_state_change(sk);
415 
416                 if (iucv->path) {
417                         low_nmcpy(user_data, iucv->src_name);
418                         high_nmcpy(user_data, iucv->dst_name);
419                         ASCEBC(user_data, sizeof(user_data));
420                         err = iucv_path_sever(iucv->path, user_data);
421                         iucv_path_free(iucv->path);
422                         iucv->path = NULL;
423                 }
424 
425                 sk->sk_err = ECONNRESET;
426                 sk->sk_state_change(sk);
427 
428                 skb_queue_purge(&iucv->send_skb_q);
429                 skb_queue_purge(&iucv->backlog_skb_q);
430                 break;
431 
432         default:
433                 /* nothing to do here */
434                 break;
435         }
436 
437         /* mark socket for deletion by iucv_sock_kill() */
438         sock_set_flag(sk, SOCK_ZAPPED);
439 
440         release_sock(sk);
441 }
442 
443 static void iucv_sock_init(struct sock *sk, struct sock *parent)
444 {
445         if (parent)
446                 sk->sk_type = parent->sk_type;
447 }
448 
449 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
450 {
451         struct sock *sk;
452 
453         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
454         if (!sk)
455                 return NULL;
456 
457         sock_init_data(sock, sk);
458         INIT_LIST_HEAD(&iucv_sk(sk)->accept_q);
459         spin_lock_init(&iucv_sk(sk)->accept_q_lock);
460         skb_queue_head_init(&iucv_sk(sk)->send_skb_q);
461         INIT_LIST_HEAD(&iucv_sk(sk)->message_q.list);
462         spin_lock_init(&iucv_sk(sk)->message_q.lock);
463         skb_queue_head_init(&iucv_sk(sk)->backlog_skb_q);
464         iucv_sk(sk)->send_tag = 0;
465         iucv_sk(sk)->flags = 0;
466         iucv_sk(sk)->msglimit = IUCV_QUEUELEN_DEFAULT;
467         iucv_sk(sk)->path = NULL;
468         memset(&iucv_sk(sk)->src_user_id , 0, 32);
469 
470         sk->sk_destruct = iucv_sock_destruct;
471         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
472         sk->sk_allocation = GFP_DMA;
473 
474         sock_reset_flag(sk, SOCK_ZAPPED);
475 
476         sk->sk_protocol = proto;
477         sk->sk_state    = IUCV_OPEN;
478 
479         setup_timer(&sk->sk_timer, iucv_sock_timeout, (unsigned long)sk);
480 
481         iucv_sock_link(&iucv_sk_list, sk);
482         return sk;
483 }
484 
485 /* Create an IUCV socket */
486 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
487                             int kern)
488 {
489         struct sock *sk;
490 
491         if (protocol && protocol != PF_IUCV)
492                 return -EPROTONOSUPPORT;
493 
494         sock->state = SS_UNCONNECTED;
495 
496         switch (sock->type) {
497         case SOCK_STREAM:
498                 sock->ops = &iucv_sock_ops;
499                 break;
500         case SOCK_SEQPACKET:
501                 /* currently, proto ops can handle both sk types */
502                 sock->ops = &iucv_sock_ops;
503                 break;
504         default:
505                 return -ESOCKTNOSUPPORT;
506         }
507 
508         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
509         if (!sk)
510                 return -ENOMEM;
511 
512         iucv_sock_init(sk, NULL);
513 
514         return 0;
515 }
516 
517 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
518 {
519         write_lock_bh(&l->lock);
520         sk_add_node(sk, &l->head);
521         write_unlock_bh(&l->lock);
522 }
523 
524 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
525 {
526         write_lock_bh(&l->lock);
527         sk_del_node_init(sk);
528         write_unlock_bh(&l->lock);
529 }
530 
531 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
532 {
533         unsigned long flags;
534         struct iucv_sock *par = iucv_sk(parent);
535 
536         sock_hold(sk);
537         spin_lock_irqsave(&par->accept_q_lock, flags);
538         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
539         spin_unlock_irqrestore(&par->accept_q_lock, flags);
540         iucv_sk(sk)->parent = parent;
541         sk_acceptq_added(parent);
542 }
543 
544 void iucv_accept_unlink(struct sock *sk)
545 {
546         unsigned long flags;
547         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
548 
549         spin_lock_irqsave(&par->accept_q_lock, flags);
550         list_del_init(&iucv_sk(sk)->accept_q);
551         spin_unlock_irqrestore(&par->accept_q_lock, flags);
552         sk_acceptq_removed(iucv_sk(sk)->parent);
553         iucv_sk(sk)->parent = NULL;
554         sock_put(sk);
555 }
556 
557 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
558 {
559         struct iucv_sock *isk, *n;
560         struct sock *sk;
561 
562         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
563                 sk = (struct sock *) isk;
564                 lock_sock(sk);
565 
566                 if (sk->sk_state == IUCV_CLOSED) {
567                         iucv_accept_unlink(sk);
568                         release_sock(sk);
569                         continue;
570                 }
571 
572                 if (sk->sk_state == IUCV_CONNECTED ||
573                     sk->sk_state == IUCV_SEVERED ||
574                     sk->sk_state == IUCV_DISCONN ||     /* due to PM restore */
575                     !newsock) {
576                         iucv_accept_unlink(sk);
577                         if (newsock)
578                                 sock_graft(sk, newsock);
579 
580                         if (sk->sk_state == IUCV_SEVERED)
581                                 sk->sk_state = IUCV_DISCONN;
582 
583                         release_sock(sk);
584                         return sk;
585                 }
586 
587                 release_sock(sk);
588         }
589         return NULL;
590 }
591 
592 /* Bind an unbound socket */
593 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
594                           int addr_len)
595 {
596         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
597         struct sock *sk = sock->sk;
598         struct iucv_sock *iucv;
599         int err;
600 
601         /* Verify the input sockaddr */
602         if (!addr || addr->sa_family != AF_IUCV)
603                 return -EINVAL;
604 
605         lock_sock(sk);
606         if (sk->sk_state != IUCV_OPEN) {
607                 err = -EBADFD;
608                 goto done;
609         }
610 
611         write_lock_bh(&iucv_sk_list.lock);
612 
613         iucv = iucv_sk(sk);
614         if (__iucv_get_sock_by_name(sa->siucv_name)) {
615                 err = -EADDRINUSE;
616                 goto done_unlock;
617         }
618         if (iucv->path) {
619                 err = 0;
620                 goto done_unlock;
621         }
622 
623         /* Bind the socket */
624         memcpy(iucv->src_name, sa->siucv_name, 8);
625 
626         /* Copy the user id */
627         memcpy(iucv->src_user_id, iucv_userid, 8);
628         sk->sk_state = IUCV_BOUND;
629         err = 0;
630 
631 done_unlock:
632         /* Release the socket list lock */
633         write_unlock_bh(&iucv_sk_list.lock);
634 done:
635         release_sock(sk);
636         return err;
637 }
638 
639 /* Automatically bind an unbound socket */
640 static int iucv_sock_autobind(struct sock *sk)
641 {
642         struct iucv_sock *iucv = iucv_sk(sk);
643         char query_buffer[80];
644         char name[12];
645         int err = 0;
646 
647         /* Set the userid and name */
648         cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
649         if (unlikely(err))
650                 return -EPROTO;
651 
652         memcpy(iucv->src_user_id, query_buffer, 8);
653 
654         write_lock_bh(&iucv_sk_list.lock);
655 
656         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
657         while (__iucv_get_sock_by_name(name)) {
658                 sprintf(name, "%08x",
659                         atomic_inc_return(&iucv_sk_list.autobind_name));
660         }
661 
662         write_unlock_bh(&iucv_sk_list.lock);
663 
664         memcpy(&iucv->src_name, name, 8);
665 
666         return err;
667 }
668 
669 /* Connect an unconnected socket */
670 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
671                              int alen, int flags)
672 {
673         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
674         struct sock *sk = sock->sk;
675         struct iucv_sock *iucv;
676         unsigned char user_data[16];
677         int err;
678 
679         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
680                 return -EINVAL;
681 
682         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
683                 return -EBADFD;
684 
685         if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
686                 return -EINVAL;
687 
688         if (sk->sk_state == IUCV_OPEN) {
689                 err = iucv_sock_autobind(sk);
690                 if (unlikely(err))
691                         return err;
692         }
693 
694         lock_sock(sk);
695 
696         /* Set the destination information */
697         memcpy(iucv_sk(sk)->dst_user_id, sa->siucv_user_id, 8);
698         memcpy(iucv_sk(sk)->dst_name, sa->siucv_name, 8);
699 
700         high_nmcpy(user_data, sa->siucv_name);
701         low_nmcpy(user_data, iucv_sk(sk)->src_name);
702         ASCEBC(user_data, sizeof(user_data));
703 
704         iucv = iucv_sk(sk);
705         /* Create path. */
706         iucv->path = iucv_path_alloc(iucv->msglimit,
707                                      IUCV_IPRMDATA, GFP_KERNEL);
708         if (!iucv->path) {
709                 err = -ENOMEM;
710                 goto done;
711         }
712         err = iucv_path_connect(iucv->path, &af_iucv_handler,
713                                 sa->siucv_user_id, NULL, user_data, sk);
714         if (err) {
715                 iucv_path_free(iucv->path);
716                 iucv->path = NULL;
717                 switch (err) {
718                 case 0x0b:      /* Target communicator is not logged on */
719                         err = -ENETUNREACH;
720                         break;
721                 case 0x0d:      /* Max connections for this guest exceeded */
722                 case 0x0e:      /* Max connections for target guest exceeded */
723                         err = -EAGAIN;
724                         break;
725                 case 0x0f:      /* Missing IUCV authorization */
726                         err = -EACCES;
727                         break;
728                 default:
729                         err = -ECONNREFUSED;
730                         break;
731                 }
732                 goto done;
733         }
734 
735         if (sk->sk_state != IUCV_CONNECTED) {
736                 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
737                                                             IUCV_DISCONN),
738                                      sock_sndtimeo(sk, flags & O_NONBLOCK));
739         }
740 
741         if (sk->sk_state == IUCV_DISCONN) {
742                 err = -ECONNREFUSED;
743         }
744 
745         if (err) {
746                 iucv_path_sever(iucv->path, NULL);
747                 iucv_path_free(iucv->path);
748                 iucv->path = NULL;
749         }
750 
751 done:
752         release_sock(sk);
753         return err;
754 }
755 
756 /* Move a socket into listening state. */
757 static int iucv_sock_listen(struct socket *sock, int backlog)
758 {
759         struct sock *sk = sock->sk;
760         int err;
761 
762         lock_sock(sk);
763 
764         err = -EINVAL;
765         if (sk->sk_state != IUCV_BOUND)
766                 goto done;
767 
768         if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
769                 goto done;
770 
771         sk->sk_max_ack_backlog = backlog;
772         sk->sk_ack_backlog = 0;
773         sk->sk_state = IUCV_LISTEN;
774         err = 0;
775 
776 done:
777         release_sock(sk);
778         return err;
779 }
780 
781 /* Accept a pending connection */
782 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
783                             int flags)
784 {
785         DECLARE_WAITQUEUE(wait, current);
786         struct sock *sk = sock->sk, *nsk;
787         long timeo;
788         int err = 0;
789 
790         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
791 
792         if (sk->sk_state != IUCV_LISTEN) {
793                 err = -EBADFD;
794                 goto done;
795         }
796 
797         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
798 
799         /* Wait for an incoming connection */
800         add_wait_queue_exclusive(sk_sleep(sk), &wait);
801         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
802                 set_current_state(TASK_INTERRUPTIBLE);
803                 if (!timeo) {
804                         err = -EAGAIN;
805                         break;
806                 }
807 
808                 release_sock(sk);
809                 timeo = schedule_timeout(timeo);
810                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
811 
812                 if (sk->sk_state != IUCV_LISTEN) {
813                         err = -EBADFD;
814                         break;
815                 }
816 
817                 if (signal_pending(current)) {
818                         err = sock_intr_errno(timeo);
819                         break;
820                 }
821         }
822 
823         set_current_state(TASK_RUNNING);
824         remove_wait_queue(sk_sleep(sk), &wait);
825 
826         if (err)
827                 goto done;
828 
829         newsock->state = SS_CONNECTED;
830 
831 done:
832         release_sock(sk);
833         return err;
834 }
835 
836 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
837                              int *len, int peer)
838 {
839         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
840         struct sock *sk = sock->sk;
841 
842         addr->sa_family = AF_IUCV;
843         *len = sizeof(struct sockaddr_iucv);
844 
845         if (peer) {
846                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->dst_user_id, 8);
847                 memcpy(siucv->siucv_name, &iucv_sk(sk)->dst_name, 8);
848         } else {
849                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->src_user_id, 8);
850                 memcpy(siucv->siucv_name, iucv_sk(sk)->src_name, 8);
851         }
852         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
853         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
854         memset(siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
855 
856         return 0;
857 }
858 
859 /**
860  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
861  * @path:       IUCV path
862  * @msg:        Pointer to a struct iucv_message
863  * @skb:        The socket data to send, skb->len MUST BE <= 7
864  *
865  * Send the socket data in the parameter list in the iucv message
866  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
867  * list and the socket data len at index 7 (last byte).
868  * See also iucv_msg_length().
869  *
870  * Returns the error code from the iucv_message_send() call.
871  */
872 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
873                           struct sk_buff *skb)
874 {
875         u8 prmdata[8];
876 
877         memcpy(prmdata, (void *) skb->data, skb->len);
878         prmdata[7] = 0xff - (u8) skb->len;
879         return iucv_message_send(path, msg, IUCV_IPRMDATA, 0,
880                                  (void *) prmdata, 8);
881 }
882 
883 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
884                              struct msghdr *msg, size_t len)
885 {
886         struct sock *sk = sock->sk;
887         struct iucv_sock *iucv = iucv_sk(sk);
888         struct sk_buff *skb;
889         struct iucv_message txmsg;
890         struct cmsghdr *cmsg;
891         int cmsg_done;
892         long timeo;
893         char user_id[9];
894         char appl_id[9];
895         int err;
896         int noblock = msg->msg_flags & MSG_DONTWAIT;
897 
898         err = sock_error(sk);
899         if (err)
900                 return err;
901 
902         if (msg->msg_flags & MSG_OOB)
903                 return -EOPNOTSUPP;
904 
905         /* SOCK_SEQPACKET: we do not support segmented records */
906         if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
907                 return -EOPNOTSUPP;
908 
909         lock_sock(sk);
910 
911         if (sk->sk_shutdown & SEND_SHUTDOWN) {
912                 err = -EPIPE;
913                 goto out;
914         }
915 
916         /* Return if the socket is not in connected state */
917         if (sk->sk_state != IUCV_CONNECTED) {
918                 err = -ENOTCONN;
919                 goto out;
920         }
921 
922         /* initialize defaults */
923         cmsg_done   = 0;        /* check for duplicate headers */
924         txmsg.class = 0;
925 
926         /* iterate over control messages */
927         for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
928                 cmsg = CMSG_NXTHDR(msg, cmsg)) {
929 
930                 if (!CMSG_OK(msg, cmsg)) {
931                         err = -EINVAL;
932                         goto out;
933                 }
934 
935                 if (cmsg->cmsg_level != SOL_IUCV)
936                         continue;
937 
938                 if (cmsg->cmsg_type & cmsg_done) {
939                         err = -EINVAL;
940                         goto out;
941                 }
942                 cmsg_done |= cmsg->cmsg_type;
943 
944                 switch (cmsg->cmsg_type) {
945                 case SCM_IUCV_TRGCLS:
946                         if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
947                                 err = -EINVAL;
948                                 goto out;
949                         }
950 
951                         /* set iucv message target class */
952                         memcpy(&txmsg.class,
953                                 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
954 
955                         break;
956 
957                 default:
958                         err = -EINVAL;
959                         goto out;
960                         break;
961                 }
962         }
963 
964         /* allocate one skb for each iucv message:
965          * this is fine for SOCK_SEQPACKET (unless we want to support
966          * segmented records using the MSG_EOR flag), but
967          * for SOCK_STREAM we might want to improve it in future */
968         skb = sock_alloc_send_skb(sk, len, noblock, &err);
969         if (!skb)
970                 goto out;
971         if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
972                 err = -EFAULT;
973                 goto fail;
974         }
975 
976         /* wait if outstanding messages for iucv path has reached */
977         timeo = sock_sndtimeo(sk, noblock);
978         err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
979         if (err)
980                 goto fail;
981 
982         /* return -ECONNRESET if the socket is no longer connected */
983         if (sk->sk_state != IUCV_CONNECTED) {
984                 err = -ECONNRESET;
985                 goto fail;
986         }
987 
988         /* increment and save iucv message tag for msg_completion cbk */
989         txmsg.tag = iucv->send_tag++;
990         memcpy(CB_TAG(skb), &txmsg.tag, CB_TAG_LEN);
991         skb_queue_tail(&iucv->send_skb_q, skb);
992 
993         if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)
994               && skb->len <= 7) {
995                 err = iucv_send_iprm(iucv->path, &txmsg, skb);
996 
997                 /* on success: there is no message_complete callback
998                  * for an IPRMDATA msg; remove skb from send queue */
999                 if (err == 0) {
1000                         skb_unlink(skb, &iucv->send_skb_q);
1001                         kfree_skb(skb);
1002                 }
1003 
1004                 /* this error should never happen since the
1005                  * IUCV_IPRMDATA path flag is set... sever path */
1006                 if (err == 0x15) {
1007                         iucv_path_sever(iucv->path, NULL);
1008                         skb_unlink(skb, &iucv->send_skb_q);
1009                         err = -EPIPE;
1010                         goto fail;
1011                 }
1012         } else
1013                 err = iucv_message_send(iucv->path, &txmsg, 0, 0,
1014                                         (void *) skb->data, skb->len);
1015         if (err) {
1016                 if (err == 3) {
1017                         user_id[8] = 0;
1018                         memcpy(user_id, iucv->dst_user_id, 8);
1019                         appl_id[8] = 0;
1020                         memcpy(appl_id, iucv->dst_name, 8);
1021                         pr_err("Application %s on z/VM guest %s"
1022                                 " exceeds message limit\n",
1023                                 appl_id, user_id);
1024                         err = -EAGAIN;
1025                 } else
1026                         err = -EPIPE;
1027                 skb_unlink(skb, &iucv->send_skb_q);
1028                 goto fail;
1029         }
1030 
1031         release_sock(sk);
1032         return len;
1033 
1034 fail:
1035         kfree_skb(skb);
1036 out:
1037         release_sock(sk);
1038         return err;
1039 }
1040 
1041 /* iucv_fragment_skb() - Fragment a single IUCV message into multiple skb's
1042  *
1043  * Locking: must be called with message_q.lock held
1044  */
1045 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
1046 {
1047         int dataleft, size, copied = 0;
1048         struct sk_buff *nskb;
1049 
1050         dataleft = len;
1051         while (dataleft) {
1052                 if (dataleft >= sk->sk_rcvbuf / 4)
1053                         size = sk->sk_rcvbuf / 4;
1054                 else
1055                         size = dataleft;
1056 
1057                 nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
1058                 if (!nskb)
1059                         return -ENOMEM;
1060 
1061                 /* copy target class to control buffer of new skb */
1062                 memcpy(CB_TRGCLS(nskb), CB_TRGCLS(skb), CB_TRGCLS_LEN);
1063 
1064                 /* copy data fragment */
1065                 memcpy(nskb->data, skb->data + copied, size);
1066                 copied += size;
1067                 dataleft -= size;
1068 
1069                 skb_reset_transport_header(nskb);
1070                 skb_reset_network_header(nskb);
1071                 nskb->len = size;
1072 
1073                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
1074         }
1075 
1076         return 0;
1077 }
1078 
1079 /* iucv_process_message() - Receive a single outstanding IUCV message
1080  *
1081  * Locking: must be called with message_q.lock held
1082  */
1083 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1084                                  struct iucv_path *path,
1085                                  struct iucv_message *msg)
1086 {
1087         int rc;
1088         unsigned int len;
1089 
1090         len = iucv_msg_length(msg);
1091 
1092         /* store msg target class in the second 4 bytes of skb ctrl buffer */
1093         /* Note: the first 4 bytes are reserved for msg tag */
1094         memcpy(CB_TRGCLS(skb), &msg->class, CB_TRGCLS_LEN);
1095 
1096         /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1097         if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1098                 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1099                         skb->data = NULL;
1100                         skb->len = 0;
1101                 }
1102         } else {
1103                 rc = iucv_message_receive(path, msg, msg->flags & IUCV_IPRMDATA,
1104                                           skb->data, len, NULL);
1105                 if (rc) {
1106                         kfree_skb(skb);
1107                         return;
1108                 }
1109                 /* we need to fragment iucv messages for SOCK_STREAM only;
1110                  * for SOCK_SEQPACKET, it is only relevant if we support
1111                  * record segmentation using MSG_EOR (see also recvmsg()) */
1112                 if (sk->sk_type == SOCK_STREAM &&
1113                     skb->truesize >= sk->sk_rcvbuf / 4) {
1114                         rc = iucv_fragment_skb(sk, skb, len);
1115                         kfree_skb(skb);
1116                         skb = NULL;
1117                         if (rc) {
1118                                 iucv_path_sever(path, NULL);
1119                                 return;
1120                         }
1121                         skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
1122                 } else {
1123                         skb_reset_transport_header(skb);
1124                         skb_reset_network_header(skb);
1125                         skb->len = len;
1126                 }
1127         }
1128 
1129         if (sock_queue_rcv_skb(sk, skb))
1130                 skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
1131 }
1132 
1133 /* iucv_process_message_q() - Process outstanding IUCV messages
1134  *
1135  * Locking: must be called with message_q.lock held
1136  */
1137 static void iucv_process_message_q(struct sock *sk)
1138 {
1139         struct iucv_sock *iucv = iucv_sk(sk);
1140         struct sk_buff *skb;
1141         struct sock_msg_q *p, *n;
1142 
1143         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1144                 skb = alloc_skb(iucv_msg_length(&p->msg), GFP_ATOMIC | GFP_DMA);
1145                 if (!skb)
1146                         break;
1147                 iucv_process_message(sk, skb, p->path, &p->msg);
1148                 list_del(&p->list);
1149                 kfree(p);
1150                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1151                         break;
1152         }
1153 }
1154 
1155 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
1156                              struct msghdr *msg, size_t len, int flags)
1157 {
1158         int noblock = flags & MSG_DONTWAIT;
1159         struct sock *sk = sock->sk;
1160         struct iucv_sock *iucv = iucv_sk(sk);
1161         unsigned int copied, rlen;
1162         struct sk_buff *skb, *rskb, *cskb;
1163         int err = 0;
1164 
1165         if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
1166             skb_queue_empty(&iucv->backlog_skb_q) &&
1167             skb_queue_empty(&sk->sk_receive_queue) &&
1168             list_empty(&iucv->message_q.list))
1169                 return 0;
1170 
1171         if (flags & (MSG_OOB))
1172                 return -EOPNOTSUPP;
1173 
1174         /* receive/dequeue next skb:
1175          * the function understands MSG_PEEK and, thus, does not dequeue skb */
1176         skb = skb_recv_datagram(sk, flags, noblock, &err);
1177         if (!skb) {
1178                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1179                         return 0;
1180                 return err;
1181         }
1182 
1183         rlen   = skb->len;              /* real length of skb */
1184         copied = min_t(unsigned int, rlen, len);
1185 
1186         cskb = skb;
1187         if (memcpy_toiovec(msg->msg_iov, cskb->data, copied)) {
1188                 if (!(flags & MSG_PEEK))
1189                         skb_queue_head(&sk->sk_receive_queue, skb);
1190                 return -EFAULT;
1191         }
1192 
1193         /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1194         if (sk->sk_type == SOCK_SEQPACKET) {
1195                 if (copied < rlen)
1196                         msg->msg_flags |= MSG_TRUNC;
1197                 /* each iucv message contains a complete record */
1198                 msg->msg_flags |= MSG_EOR;
1199         }
1200 
1201         /* create control message to store iucv msg target class:
1202          * get the trgcls from the control buffer of the skb due to
1203          * fragmentation of original iucv message. */
1204         err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1205                         CB_TRGCLS_LEN, CB_TRGCLS(skb));
1206         if (err) {
1207                 if (!(flags & MSG_PEEK))
1208                         skb_queue_head(&sk->sk_receive_queue, skb);
1209                 return err;
1210         }
1211 
1212         /* Mark read part of skb as used */
1213         if (!(flags & MSG_PEEK)) {
1214 
1215                 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1216                 if (sk->sk_type == SOCK_STREAM) {
1217                         skb_pull(skb, copied);
1218                         if (skb->len) {
1219                                 skb_queue_head(&sk->sk_receive_queue, skb);
1220                                 goto done;
1221                         }
1222                 }
1223 
1224                 kfree_skb(skb);
1225 
1226                 /* Queue backlog skbs */
1227                 spin_lock_bh(&iucv->message_q.lock);
1228                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1229                 while (rskb) {
1230                         if (sock_queue_rcv_skb(sk, rskb)) {
1231                                 skb_queue_head(&iucv->backlog_skb_q,
1232                                                 rskb);
1233                                 break;
1234                         } else {
1235                                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1236                         }
1237                 }
1238                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1239                         if (!list_empty(&iucv->message_q.list))
1240                                 iucv_process_message_q(sk);
1241                 }
1242                 spin_unlock_bh(&iucv->message_q.lock);
1243         }
1244 
1245 done:
1246         /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1247         if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1248                 copied = rlen;
1249 
1250         return copied;
1251 }
1252 
1253 static inline unsigned int iucv_accept_poll(struct sock *parent)
1254 {
1255         struct iucv_sock *isk, *n;
1256         struct sock *sk;
1257 
1258         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1259                 sk = (struct sock *) isk;
1260 
1261                 if (sk->sk_state == IUCV_CONNECTED)
1262                         return POLLIN | POLLRDNORM;
1263         }
1264 
1265         return 0;
1266 }
1267 
1268 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
1269                             poll_table *wait)
1270 {
1271         struct sock *sk = sock->sk;
1272         unsigned int mask = 0;
1273 
1274         sock_poll_wait(file, sk_sleep(sk), wait);
1275 
1276         if (sk->sk_state == IUCV_LISTEN)
1277                 return iucv_accept_poll(sk);
1278 
1279         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1280                 mask |= POLLERR;
1281 
1282         if (sk->sk_shutdown & RCV_SHUTDOWN)
1283                 mask |= POLLRDHUP;
1284 
1285         if (sk->sk_shutdown == SHUTDOWN_MASK)
1286                 mask |= POLLHUP;
1287 
1288         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1289             (sk->sk_shutdown & RCV_SHUTDOWN))
1290                 mask |= POLLIN | POLLRDNORM;
1291 
1292         if (sk->sk_state == IUCV_CLOSED)
1293                 mask |= POLLHUP;
1294 
1295         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
1296                 mask |= POLLIN;
1297 
1298         if (sock_writeable(sk))
1299                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1300         else
1301                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1302 
1303         return mask;
1304 }
1305 
1306 static int iucv_sock_shutdown(struct socket *sock, int how)
1307 {
1308         struct sock *sk = sock->sk;
1309         struct iucv_sock *iucv = iucv_sk(sk);
1310         struct iucv_message txmsg;
1311         int err = 0;
1312 
1313         how++;
1314 
1315         if ((how & ~SHUTDOWN_MASK) || !how)
1316                 return -EINVAL;
1317 
1318         lock_sock(sk);
1319         switch (sk->sk_state) {
1320         case IUCV_DISCONN:
1321         case IUCV_CLOSING:
1322         case IUCV_SEVERED:
1323         case IUCV_CLOSED:
1324                 err = -ENOTCONN;
1325                 goto fail;
1326 
1327         default:
1328                 sk->sk_shutdown |= how;
1329                 break;
1330         }
1331 
1332         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1333                 txmsg.class = 0;
1334                 txmsg.tag = 0;
1335                 err = iucv_message_send(iucv->path, &txmsg, IUCV_IPRMDATA, 0,
1336                                         (void *) iprm_shutdown, 8);
1337                 if (err) {
1338                         switch (err) {
1339                         case 1:
1340                                 err = -ENOTCONN;
1341                                 break;
1342                         case 2:
1343                                 err = -ECONNRESET;
1344                                 break;
1345                         default:
1346                                 err = -ENOTCONN;
1347                                 break;
1348                         }
1349                 }
1350         }
1351 
1352         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1353                 err = iucv_path_quiesce(iucv_sk(sk)->path, NULL);
1354                 if (err)
1355                         err = -ENOTCONN;
1356 
1357                 skb_queue_purge(&sk->sk_receive_queue);
1358         }
1359 
1360         /* Wake up anyone sleeping in poll */
1361         sk->sk_state_change(sk);
1362 
1363 fail:
1364         release_sock(sk);
1365         return err;
1366 }
1367 
1368 static int iucv_sock_release(struct socket *sock)
1369 {
1370         struct sock *sk = sock->sk;
1371         int err = 0;
1372 
1373         if (!sk)
1374                 return 0;
1375 
1376         iucv_sock_close(sk);
1377 
1378         /* Unregister with IUCV base support */
1379         if (iucv_sk(sk)->path) {
1380                 iucv_path_sever(iucv_sk(sk)->path, NULL);
1381                 iucv_path_free(iucv_sk(sk)->path);
1382                 iucv_sk(sk)->path = NULL;
1383         }
1384 
1385         sock_orphan(sk);
1386         iucv_sock_kill(sk);
1387         return err;
1388 }
1389 
1390 /* getsockopt and setsockopt */
1391 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1392                                 char __user *optval, unsigned int optlen)
1393 {
1394         struct sock *sk = sock->sk;
1395         struct iucv_sock *iucv = iucv_sk(sk);
1396         int val;
1397         int rc;
1398 
1399         if (level != SOL_IUCV)
1400                 return -ENOPROTOOPT;
1401 
1402         if (optlen < sizeof(int))
1403                 return -EINVAL;
1404 
1405         if (get_user(val, (int __user *) optval))
1406                 return -EFAULT;
1407 
1408         rc = 0;
1409 
1410         lock_sock(sk);
1411         switch (optname) {
1412         case SO_IPRMDATA_MSG:
1413                 if (val)
1414                         iucv->flags |= IUCV_IPRMDATA;
1415                 else
1416                         iucv->flags &= ~IUCV_IPRMDATA;
1417                 break;
1418         case SO_MSGLIMIT:
1419                 switch (sk->sk_state) {
1420                 case IUCV_OPEN:
1421                 case IUCV_BOUND:
1422                         if (val < 1 || val > (u16)(~0))
1423                                 rc = -EINVAL;
1424                         else
1425                                 iucv->msglimit = val;
1426                         break;
1427                 default:
1428                         rc = -EINVAL;
1429                         break;
1430                 }
1431                 break;
1432         default:
1433                 rc = -ENOPROTOOPT;
1434                 break;
1435         }
1436         release_sock(sk);
1437 
1438         return rc;
1439 }
1440 
1441 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1442                                 char __user *optval, int __user *optlen)
1443 {
1444         struct sock *sk = sock->sk;
1445         struct iucv_sock *iucv = iucv_sk(sk);
1446         int val, len;
1447 
1448         if (level != SOL_IUCV)
1449                 return -ENOPROTOOPT;
1450 
1451         if (get_user(len, optlen))
1452                 return -EFAULT;
1453 
1454         if (len < 0)
1455                 return -EINVAL;
1456 
1457         len = min_t(unsigned int, len, sizeof(int));
1458 
1459         switch (optname) {
1460         case SO_IPRMDATA_MSG:
1461                 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1462                 break;
1463         case SO_MSGLIMIT:
1464                 lock_sock(sk);
1465                 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1466                                            : iucv->msglimit;    /* default */
1467                 release_sock(sk);
1468                 break;
1469         default:
1470                 return -ENOPROTOOPT;
1471         }
1472 
1473         if (put_user(len, optlen))
1474                 return -EFAULT;
1475         if (copy_to_user(optval, &val, len))
1476                 return -EFAULT;
1477 
1478         return 0;
1479 }
1480 
1481 
1482 /* Callback wrappers - called from iucv base support */
1483 static int iucv_callback_connreq(struct iucv_path *path,
1484                                  u8 ipvmid[8], u8 ipuser[16])
1485 {
1486         unsigned char user_data[16];
1487         unsigned char nuser_data[16];
1488         unsigned char src_name[8];
1489         struct hlist_node *node;
1490         struct sock *sk, *nsk;
1491         struct iucv_sock *iucv, *niucv;
1492         int err;
1493 
1494         memcpy(src_name, ipuser, 8);
1495         EBCASC(src_name, 8);
1496         /* Find out if this path belongs to af_iucv. */
1497         read_lock(&iucv_sk_list.lock);
1498         iucv = NULL;
1499         sk = NULL;
1500         sk_for_each(sk, node, &iucv_sk_list.head)
1501                 if (sk->sk_state == IUCV_LISTEN &&
1502                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1503                         /*
1504                          * Found a listening socket with
1505                          * src_name == ipuser[0-7].
1506                          */
1507                         iucv = iucv_sk(sk);
1508                         break;
1509                 }
1510         read_unlock(&iucv_sk_list.lock);
1511         if (!iucv)
1512                 /* No socket found, not one of our paths. */
1513                 return -EINVAL;
1514 
1515         bh_lock_sock(sk);
1516 
1517         /* Check if parent socket is listening */
1518         low_nmcpy(user_data, iucv->src_name);
1519         high_nmcpy(user_data, iucv->dst_name);
1520         ASCEBC(user_data, sizeof(user_data));
1521         if (sk->sk_state != IUCV_LISTEN) {
1522                 err = iucv_path_sever(path, user_data);
1523                 iucv_path_free(path);
1524                 goto fail;
1525         }
1526 
1527         /* Check for backlog size */
1528         if (sk_acceptq_is_full(sk)) {
1529                 err = iucv_path_sever(path, user_data);
1530                 iucv_path_free(path);
1531                 goto fail;
1532         }
1533 
1534         /* Create the new socket */
1535         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1536         if (!nsk) {
1537                 err = iucv_path_sever(path, user_data);
1538                 iucv_path_free(path);
1539                 goto fail;
1540         }
1541 
1542         niucv = iucv_sk(nsk);
1543         iucv_sock_init(nsk, sk);
1544 
1545         /* Set the new iucv_sock */
1546         memcpy(niucv->dst_name, ipuser + 8, 8);
1547         EBCASC(niucv->dst_name, 8);
1548         memcpy(niucv->dst_user_id, ipvmid, 8);
1549         memcpy(niucv->src_name, iucv->src_name, 8);
1550         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1551         niucv->path = path;
1552 
1553         /* Call iucv_accept */
1554         high_nmcpy(nuser_data, ipuser + 8);
1555         memcpy(nuser_data + 8, niucv->src_name, 8);
1556         ASCEBC(nuser_data + 8, 8);
1557 
1558         /* set message limit for path based on msglimit of accepting socket */
1559         niucv->msglimit = iucv->msglimit;
1560         path->msglim = iucv->msglimit;
1561         err = iucv_path_accept(path, &af_iucv_handler, nuser_data, nsk);
1562         if (err) {
1563                 err = iucv_path_sever(path, user_data);
1564                 iucv_path_free(path);
1565                 iucv_sock_kill(nsk);
1566                 goto fail;
1567         }
1568 
1569         iucv_accept_enqueue(sk, nsk);
1570 
1571         /* Wake up accept */
1572         nsk->sk_state = IUCV_CONNECTED;
1573         sk->sk_data_ready(sk, 1);
1574         err = 0;
1575 fail:
1576         bh_unlock_sock(sk);
1577         return 0;
1578 }
1579 
1580 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1581 {
1582         struct sock *sk = path->private;
1583 
1584         sk->sk_state = IUCV_CONNECTED;
1585         sk->sk_state_change(sk);
1586 }
1587 
1588 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1589 {
1590         struct sock *sk = path->private;
1591         struct iucv_sock *iucv = iucv_sk(sk);
1592         struct sk_buff *skb;
1593         struct sock_msg_q *save_msg;
1594         int len;
1595 
1596         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1597                 iucv_message_reject(path, msg);
1598                 return;
1599         }
1600 
1601         spin_lock(&iucv->message_q.lock);
1602 
1603         if (!list_empty(&iucv->message_q.list) ||
1604             !skb_queue_empty(&iucv->backlog_skb_q))
1605                 goto save_message;
1606 
1607         len = atomic_read(&sk->sk_rmem_alloc);
1608         len += iucv_msg_length(msg) + sizeof(struct sk_buff);
1609         if (len > sk->sk_rcvbuf)
1610                 goto save_message;
1611 
1612         skb = alloc_skb(iucv_msg_length(msg), GFP_ATOMIC | GFP_DMA);
1613         if (!skb)
1614                 goto save_message;
1615 
1616         iucv_process_message(sk, skb, path, msg);
1617         goto out_unlock;
1618 
1619 save_message:
1620         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1621         if (!save_msg)
1622                 goto out_unlock;
1623         save_msg->path = path;
1624         save_msg->msg = *msg;
1625 
1626         list_add_tail(&save_msg->list, &iucv->message_q.list);
1627 
1628 out_unlock:
1629         spin_unlock(&iucv->message_q.lock);
1630 }
1631 
1632 static void iucv_callback_txdone(struct iucv_path *path,
1633                                  struct iucv_message *msg)
1634 {
1635         struct sock *sk = path->private;
1636         struct sk_buff *this = NULL;
1637         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1638         struct sk_buff *list_skb = list->next;
1639         unsigned long flags;
1640 
1641         if (!skb_queue_empty(list)) {
1642                 spin_lock_irqsave(&list->lock, flags);
1643 
1644                 while (list_skb != (struct sk_buff *)list) {
1645                         if (!memcmp(&msg->tag, CB_TAG(list_skb), CB_TAG_LEN)) {
1646                                 this = list_skb;
1647                                 break;
1648                         }
1649                         list_skb = list_skb->next;
1650                 }
1651                 if (this)
1652                         __skb_unlink(this, list);
1653 
1654                 spin_unlock_irqrestore(&list->lock, flags);
1655 
1656                 if (this) {
1657                         kfree_skb(this);
1658                         /* wake up any process waiting for sending */
1659                         iucv_sock_wake_msglim(sk);
1660                 }
1661         }
1662         BUG_ON(!this);
1663 
1664         if (sk->sk_state == IUCV_CLOSING) {
1665                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1666                         sk->sk_state = IUCV_CLOSED;
1667                         sk->sk_state_change(sk);
1668                 }
1669         }
1670 
1671 }
1672 
1673 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1674 {
1675         struct sock *sk = path->private;
1676 
1677         if (!list_empty(&iucv_sk(sk)->accept_q))
1678                 sk->sk_state = IUCV_SEVERED;
1679         else
1680                 sk->sk_state = IUCV_DISCONN;
1681 
1682         sk->sk_state_change(sk);
1683 }
1684 
1685 /* called if the other communication side shuts down its RECV direction;
1686  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1687  */
1688 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1689 {
1690         struct sock *sk = path->private;
1691 
1692         bh_lock_sock(sk);
1693         if (sk->sk_state != IUCV_CLOSED) {
1694                 sk->sk_shutdown |= SEND_SHUTDOWN;
1695                 sk->sk_state_change(sk);
1696         }
1697         bh_unlock_sock(sk);
1698 }
1699 
1700 static const struct proto_ops iucv_sock_ops = {
1701         .family         = PF_IUCV,
1702         .owner          = THIS_MODULE,
1703         .release        = iucv_sock_release,
1704         .bind           = iucv_sock_bind,
1705         .connect        = iucv_sock_connect,
1706         .listen         = iucv_sock_listen,
1707         .accept         = iucv_sock_accept,
1708         .getname        = iucv_sock_getname,
1709         .sendmsg        = iucv_sock_sendmsg,
1710         .recvmsg        = iucv_sock_recvmsg,
1711         .poll           = iucv_sock_poll,
1712         .ioctl          = sock_no_ioctl,
1713         .mmap           = sock_no_mmap,
1714         .socketpair     = sock_no_socketpair,
1715         .shutdown       = iucv_sock_shutdown,
1716         .setsockopt     = iucv_sock_setsockopt,
1717         .getsockopt     = iucv_sock_getsockopt,
1718 };
1719 
1720 static const struct net_proto_family iucv_sock_family_ops = {
1721         .family = AF_IUCV,
1722         .owner  = THIS_MODULE,
1723         .create = iucv_sock_create,
1724 };
1725 
1726 static int __init afiucv_init(void)
1727 {
1728         int err;
1729 
1730         if (!MACHINE_IS_VM) {
1731                 pr_err("The af_iucv module cannot be loaded"
1732                        " without z/VM\n");
1733                 err = -EPROTONOSUPPORT;
1734                 goto out;
1735         }
1736         cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
1737         if (unlikely(err)) {
1738                 WARN_ON(err);
1739                 err = -EPROTONOSUPPORT;
1740                 goto out;
1741         }
1742 
1743         err = iucv_register(&af_iucv_handler, 0);
1744         if (err)
1745                 goto out;
1746         err = proto_register(&iucv_proto, 0);
1747         if (err)
1748                 goto out_iucv;
1749         err = sock_register(&iucv_sock_family_ops);
1750         if (err)
1751                 goto out_proto;
1752         /* establish dummy device */
1753         err = driver_register(&af_iucv_driver);
1754         if (err)
1755                 goto out_sock;
1756         af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
1757         if (!af_iucv_dev) {
1758                 err = -ENOMEM;
1759                 goto out_driver;
1760         }
1761         dev_set_name(af_iucv_dev, "af_iucv");
1762         af_iucv_dev->bus = &iucv_bus;
1763         af_iucv_dev->parent = iucv_root;
1764         af_iucv_dev->release = (void (*)(struct device *))kfree;
1765         af_iucv_dev->driver = &af_iucv_driver;
1766         err = device_register(af_iucv_dev);
1767         if (err)
1768                 goto out_driver;
1769 
1770         return 0;
1771 
1772 out_driver:
1773         driver_unregister(&af_iucv_driver);
1774 out_sock:
1775         sock_unregister(PF_IUCV);
1776 out_proto:
1777         proto_unregister(&iucv_proto);
1778 out_iucv:
1779         iucv_unregister(&af_iucv_handler, 0);
1780 out:
1781         return err;
1782 }
1783 
1784 static void __exit afiucv_exit(void)
1785 {
1786         device_unregister(af_iucv_dev);
1787         driver_unregister(&af_iucv_driver);
1788         sock_unregister(PF_IUCV);
1789         proto_unregister(&iucv_proto);
1790         iucv_unregister(&af_iucv_handler, 0);
1791 }
1792 
1793 module_init(afiucv_init);
1794 module_exit(afiucv_exit);
1795 
1796 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
1797 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
1798 MODULE_VERSION(VERSION);
1799 MODULE_LICENSE("GPL");
1800 MODULE_ALIAS_NETPROTO(PF_IUCV);
1801 

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