1 
2 /*
3  * DECnet       An implementation of the DECnet protocol suite for the LINUX
4  *              operating system.  DECnet is implemented using the  BSD Socket
5  *              interface as the means of communication with the user level.
6  *
7  *              DECnet Network Services Protocol (Output)
8  *
9  * Author:      Eduardo Marcelo Serrat <emserrat@geocities.com>
10  *
11  * Changes:
12  *
13  *    Steve Whitehouse:  Split into dn_nsp_in.c and dn_nsp_out.c from
14  *                       original dn_nsp.c.
15  *    Steve Whitehouse:  Updated to work with my new routing architecture.
16  *    Steve Whitehouse:  Added changes from Eduardo Serrat's patches.
17  *    Steve Whitehouse:  Now conninits have the "return" bit set.
18  *    Steve Whitehouse:  Fixes to check alloc'd skbs are non NULL!
19  *                       Moved output state machine into one function
20  *    Steve Whitehouse:  New output state machine
21  *         Paul Koning:  Connect Confirm message fix.
22  *      Eduardo Serrat:  Fix to stop dn_nsp_do_disc() sending malformed packets.
23  *    Steve Whitehouse:  dn_nsp_output() and friends needed a spring clean
24  *    Steve Whitehouse:  Moved dn_nsp_send() in here from route.h
25  */
26 
27 /******************************************************************************
28     (c) 1995-1998 E.M. Serrat		emserrat@geocities.com
29 
30     This program is free software; you can redistribute it and/or modify
31     it under the terms of the GNU General Public License as published by
32     the Free Software Foundation; either version 2 of the License, or
33     any later version.
34 
35     This program is distributed in the hope that it will be useful,
36     but WITHOUT ANY WARRANTY; without even the implied warranty of
37     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
38     GNU General Public License for more details.
39 *******************************************************************************/
40 
41 #include <linux/errno.h>
42 #include <linux/types.h>
43 #include <linux/socket.h>
44 #include <linux/in.h>
45 #include <linux/kernel.h>
46 #include <linux/timer.h>
47 #include <linux/string.h>
48 #include <linux/sockios.h>
49 #include <linux/net.h>
50 #include <linux/netdevice.h>
51 #include <linux/inet.h>
52 #include <linux/route.h>
53 #include <linux/slab.h>
54 #include <net/sock.h>
55 #include <linux/fcntl.h>
56 #include <linux/mm.h>
57 #include <linux/termios.h>
58 #include <linux/interrupt.h>
59 #include <linux/proc_fs.h>
60 #include <linux/stat.h>
61 #include <linux/init.h>
62 #include <linux/poll.h>
63 #include <linux/if_packet.h>
64 #include <net/neighbour.h>
65 #include <net/dst.h>
66 #include <net/flow.h>
67 #include <net/dn.h>
68 #include <net/dn_nsp.h>
69 #include <net/dn_dev.h>
70 #include <net/dn_route.h>
71 
72 
73 static int nsp_backoff[NSP_MAXRXTSHIFT + 1] = { 1, 2, 4, 8, 16, 32, 64, 64, 64, 64, 64, 64, 64 };
74 
dn_nsp_send(struct sk_buff * skb)75 static void dn_nsp_send(struct sk_buff *skb)
76 {
77 	struct sock *sk = skb->sk;
78 	struct dn_scp *scp = DN_SK(sk);
79 	struct dst_entry *dst;
80 	struct flowidn fld;
81 
82 	skb_reset_transport_header(skb);
83 	scp->stamp = jiffies;
84 
85 	dst = sk_dst_check(sk, 0);
86 	if (dst) {
87 try_again:
88 		skb_dst_set(skb, dst);
89 		dst_output(skb);
90 		return;
91 	}
92 
93 	memset(&fld, 0, sizeof(fld));
94 	fld.flowidn_oif = sk->sk_bound_dev_if;
95 	fld.saddr = dn_saddr2dn(&scp->addr);
96 	fld.daddr = dn_saddr2dn(&scp->peer);
97 	dn_sk_ports_copy(&fld, scp);
98 	fld.flowidn_proto = DNPROTO_NSP;
99 	if (dn_route_output_sock(&sk->sk_dst_cache, &fld, sk, 0) == 0) {
100 		dst = sk_dst_get(sk);
101 		sk->sk_route_caps = dst->dev->features;
102 		goto try_again;
103 	}
104 
105 	sk->sk_err = EHOSTUNREACH;
106 	if (!sock_flag(sk, SOCK_DEAD))
107 		sk->sk_state_change(sk);
108 }
109 
110 
111 /*
112  * If sk == NULL, then we assume that we are supposed to be making
113  * a routing layer skb. If sk != NULL, then we are supposed to be
114  * creating an skb for the NSP layer.
115  *
116  * The eventual aim is for each socket to have a cached header size
117  * for its outgoing packets, and to set hdr from this when sk != NULL.
118  */
dn_alloc_skb(struct sock * sk,int size,gfp_t pri)119 struct sk_buff *dn_alloc_skb(struct sock *sk, int size, gfp_t pri)
120 {
121 	struct sk_buff *skb;
122 	int hdr = 64;
123 
124 	if ((skb = alloc_skb(size + hdr, pri)) == NULL)
125 		return NULL;
126 
127 	skb->protocol = htons(ETH_P_DNA_RT);
128 	skb->pkt_type = PACKET_OUTGOING;
129 
130 	if (sk)
131 		skb_set_owner_w(skb, sk);
132 
133 	skb_reserve(skb, hdr);
134 
135 	return skb;
136 }
137 
138 /*
139  * Calculate persist timer based upon the smoothed round
140  * trip time and the variance. Backoff according to the
141  * nsp_backoff[] array.
142  */
dn_nsp_persist(struct sock * sk)143 unsigned long dn_nsp_persist(struct sock *sk)
144 {
145 	struct dn_scp *scp = DN_SK(sk);
146 
147 	unsigned long t = ((scp->nsp_srtt >> 2) + scp->nsp_rttvar) >> 1;
148 
149 	t *= nsp_backoff[scp->nsp_rxtshift];
150 
151 	if (t < HZ) t = HZ;
152 	if (t > (600*HZ)) t = (600*HZ);
153 
154 	if (scp->nsp_rxtshift < NSP_MAXRXTSHIFT)
155 		scp->nsp_rxtshift++;
156 
157 	/* printk(KERN_DEBUG "rxtshift %lu, t=%lu\n", scp->nsp_rxtshift, t); */
158 
159 	return t;
160 }
161 
162 /*
163  * This is called each time we get an estimate for the rtt
164  * on the link.
165  */
dn_nsp_rtt(struct sock * sk,long rtt)166 static void dn_nsp_rtt(struct sock *sk, long rtt)
167 {
168 	struct dn_scp *scp = DN_SK(sk);
169 	long srtt = (long)scp->nsp_srtt;
170 	long rttvar = (long)scp->nsp_rttvar;
171 	long delta;
172 
173 	/*
174 	 * If the jiffies clock flips over in the middle of timestamp
175 	 * gathering this value might turn out negative, so we make sure
176 	 * that is it always positive here.
177 	 */
178 	if (rtt < 0)
179 		rtt = -rtt;
180 	/*
181 	 * Add new rtt to smoothed average
182 	 */
183 	delta = ((rtt << 3) - srtt);
184 	srtt += (delta >> 3);
185 	if (srtt >= 1)
186 		scp->nsp_srtt = (unsigned long)srtt;
187 	else
188 		scp->nsp_srtt = 1;
189 
190 	/*
191 	 * Add new rtt varience to smoothed varience
192 	 */
193 	delta >>= 1;
194 	rttvar += ((((delta>0)?(delta):(-delta)) - rttvar) >> 2);
195 	if (rttvar >= 1)
196 		scp->nsp_rttvar = (unsigned long)rttvar;
197 	else
198 		scp->nsp_rttvar = 1;
199 
200 	/* printk(KERN_DEBUG "srtt=%lu rttvar=%lu\n", scp->nsp_srtt, scp->nsp_rttvar); */
201 }
202 
203 /**
204  * dn_nsp_clone_and_send - Send a data packet by cloning it
205  * @skb: The packet to clone and transmit
206  * @gfp: memory allocation flag
207  *
208  * Clone a queued data or other data packet and transmit it.
209  *
210  * Returns: The number of times the packet has been sent previously
211  */
dn_nsp_clone_and_send(struct sk_buff * skb,gfp_t gfp)212 static inline unsigned dn_nsp_clone_and_send(struct sk_buff *skb,
213 					     gfp_t gfp)
214 {
215 	struct dn_skb_cb *cb = DN_SKB_CB(skb);
216 	struct sk_buff *skb2;
217 	int ret = 0;
218 
219 	if ((skb2 = skb_clone(skb, gfp)) != NULL) {
220 		ret = cb->xmit_count;
221 		cb->xmit_count++;
222 		cb->stamp = jiffies;
223 		skb2->sk = skb->sk;
224 		dn_nsp_send(skb2);
225 	}
226 
227 	return ret;
228 }
229 
230 /**
231  * dn_nsp_output - Try and send something from socket queues
232  * @sk: The socket whose queues are to be investigated
233  *
234  * Try and send the packet on the end of the data and other data queues.
235  * Other data gets priority over data, and if we retransmit a packet we
236  * reduce the window by dividing it in two.
237  *
238  */
dn_nsp_output(struct sock * sk)239 void dn_nsp_output(struct sock *sk)
240 {
241 	struct dn_scp *scp = DN_SK(sk);
242 	struct sk_buff *skb;
243 	unsigned reduce_win = 0;
244 
245 	/*
246 	 * First we check for otherdata/linkservice messages
247 	 */
248 	if ((skb = skb_peek(&scp->other_xmit_queue)) != NULL)
249 		reduce_win = dn_nsp_clone_and_send(skb, GFP_ATOMIC);
250 
251 	/*
252 	 * If we may not send any data, we don't.
253 	 * If we are still trying to get some other data down the
254 	 * channel, we don't try and send any data.
255 	 */
256 	if (reduce_win || (scp->flowrem_sw != DN_SEND))
257 		goto recalc_window;
258 
259 	if ((skb = skb_peek(&scp->data_xmit_queue)) != NULL)
260 		reduce_win = dn_nsp_clone_and_send(skb, GFP_ATOMIC);
261 
262 	/*
263 	 * If we've sent any frame more than once, we cut the
264 	 * send window size in half. There is always a minimum
265 	 * window size of one available.
266 	 */
267 recalc_window:
268 	if (reduce_win) {
269 		scp->snd_window >>= 1;
270 		if (scp->snd_window < NSP_MIN_WINDOW)
271 			scp->snd_window = NSP_MIN_WINDOW;
272 	}
273 }
274 
dn_nsp_xmit_timeout(struct sock * sk)275 int dn_nsp_xmit_timeout(struct sock *sk)
276 {
277 	struct dn_scp *scp = DN_SK(sk);
278 
279 	dn_nsp_output(sk);
280 
281 	if (!skb_queue_empty(&scp->data_xmit_queue) ||
282 	    !skb_queue_empty(&scp->other_xmit_queue))
283 		scp->persist = dn_nsp_persist(sk);
284 
285 	return 0;
286 }
287 
dn_mk_common_header(struct dn_scp * scp,struct sk_buff * skb,unsigned char msgflag,int len)288 static inline __le16 *dn_mk_common_header(struct dn_scp *scp, struct sk_buff *skb, unsigned char msgflag, int len)
289 {
290 	unsigned char *ptr = skb_push(skb, len);
291 
292 	BUG_ON(len < 5);
293 
294 	*ptr++ = msgflag;
295 	*((__le16 *)ptr) = scp->addrrem;
296 	ptr += 2;
297 	*((__le16 *)ptr) = scp->addrloc;
298 	ptr += 2;
299 	return (__le16 __force *)ptr;
300 }
301 
dn_mk_ack_header(struct sock * sk,struct sk_buff * skb,unsigned char msgflag,int hlen,int other)302 static __le16 *dn_mk_ack_header(struct sock *sk, struct sk_buff *skb, unsigned char msgflag, int hlen, int other)
303 {
304 	struct dn_scp *scp = DN_SK(sk);
305 	unsigned short acknum = scp->numdat_rcv & 0x0FFF;
306 	unsigned short ackcrs = scp->numoth_rcv & 0x0FFF;
307 	__le16 *ptr;
308 
309 	BUG_ON(hlen < 9);
310 
311 	scp->ackxmt_dat = acknum;
312 	scp->ackxmt_oth = ackcrs;
313 	acknum |= 0x8000;
314 	ackcrs |= 0x8000;
315 
316 	/* If this is an "other data/ack" message, swap acknum and ackcrs */
317 	if (other) {
318 		unsigned short tmp = acknum;
319 		acknum = ackcrs;
320 		ackcrs = tmp;
321 	}
322 
323 	/* Set "cross subchannel" bit in ackcrs */
324 	ackcrs |= 0x2000;
325 
326 	ptr = (__le16 *)dn_mk_common_header(scp, skb, msgflag, hlen);
327 
328 	*ptr++ = cpu_to_le16(acknum);
329 	*ptr++ = cpu_to_le16(ackcrs);
330 
331 	return ptr;
332 }
333 
dn_nsp_mk_data_header(struct sock * sk,struct sk_buff * skb,int oth)334 static __le16 *dn_nsp_mk_data_header(struct sock *sk, struct sk_buff *skb, int oth)
335 {
336 	struct dn_scp *scp = DN_SK(sk);
337 	struct dn_skb_cb *cb = DN_SKB_CB(skb);
338 	__le16 *ptr = dn_mk_ack_header(sk, skb, cb->nsp_flags, 11, oth);
339 
340 	if (unlikely(oth)) {
341 		cb->segnum = scp->numoth;
342 		seq_add(&scp->numoth, 1);
343 	} else {
344 		cb->segnum = scp->numdat;
345 		seq_add(&scp->numdat, 1);
346 	}
347 	*(ptr++) = cpu_to_le16(cb->segnum);
348 
349 	return ptr;
350 }
351 
dn_nsp_queue_xmit(struct sock * sk,struct sk_buff * skb,gfp_t gfp,int oth)352 void dn_nsp_queue_xmit(struct sock *sk, struct sk_buff *skb,
353 			gfp_t gfp, int oth)
354 {
355 	struct dn_scp *scp = DN_SK(sk);
356 	struct dn_skb_cb *cb = DN_SKB_CB(skb);
357 	unsigned long t = ((scp->nsp_srtt >> 2) + scp->nsp_rttvar) >> 1;
358 
359 	cb->xmit_count = 0;
360 	dn_nsp_mk_data_header(sk, skb, oth);
361 
362 	/*
363 	 * Slow start: If we have been idle for more than
364 	 * one RTT, then reset window to min size.
365 	 */
366 	if ((jiffies - scp->stamp) > t)
367 		scp->snd_window = NSP_MIN_WINDOW;
368 
369 	if (oth)
370 		skb_queue_tail(&scp->other_xmit_queue, skb);
371 	else
372 		skb_queue_tail(&scp->data_xmit_queue, skb);
373 
374 	if (scp->flowrem_sw != DN_SEND)
375 		return;
376 
377 	dn_nsp_clone_and_send(skb, gfp);
378 }
379 
380 
dn_nsp_check_xmit_queue(struct sock * sk,struct sk_buff * skb,struct sk_buff_head * q,unsigned short acknum)381 int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb, struct sk_buff_head *q, unsigned short acknum)
382 {
383 	struct dn_skb_cb *cb = DN_SKB_CB(skb);
384 	struct dn_scp *scp = DN_SK(sk);
385 	struct sk_buff *skb2, *n, *ack = NULL;
386 	int wakeup = 0;
387 	int try_retrans = 0;
388 	unsigned long reftime = cb->stamp;
389 	unsigned long pkttime;
390 	unsigned short xmit_count;
391 	unsigned short segnum;
392 
393 	skb_queue_walk_safe(q, skb2, n) {
394 		struct dn_skb_cb *cb2 = DN_SKB_CB(skb2);
395 
396 		if (dn_before_or_equal(cb2->segnum, acknum))
397 			ack = skb2;
398 
399 		/* printk(KERN_DEBUG "ack: %s %04x %04x\n", ack ? "ACK" : "SKIP", (int)cb2->segnum, (int)acknum); */
400 
401 		if (ack == NULL)
402 			continue;
403 
404 		/* printk(KERN_DEBUG "check_xmit_queue: %04x, %d\n", acknum, cb2->xmit_count); */
405 
406 		/* Does _last_ packet acked have xmit_count > 1 */
407 		try_retrans = 0;
408 		/* Remember to wake up the sending process */
409 		wakeup = 1;
410 		/* Keep various statistics */
411 		pkttime = cb2->stamp;
412 		xmit_count = cb2->xmit_count;
413 		segnum = cb2->segnum;
414 		/* Remove and drop ack'ed packet */
415 		skb_unlink(ack, q);
416 		kfree_skb(ack);
417 		ack = NULL;
418 
419 		/*
420 		 * We don't expect to see acknowledgements for packets we
421 		 * haven't sent yet.
422 		 */
423 		WARN_ON(xmit_count == 0);
424 
425 		/*
426 		 * If the packet has only been sent once, we can use it
427 		 * to calculate the RTT and also open the window a little
428 		 * further.
429 		 */
430 		if (xmit_count == 1) {
431 			if (dn_equal(segnum, acknum))
432 				dn_nsp_rtt(sk, (long)(pkttime - reftime));
433 
434 			if (scp->snd_window < scp->max_window)
435 				scp->snd_window++;
436 		}
437 
438 		/*
439 		 * Packet has been sent more than once. If this is the last
440 		 * packet to be acknowledged then we want to send the next
441 		 * packet in the send queue again (assumes the remote host does
442 		 * go-back-N error control).
443 		 */
444 		if (xmit_count > 1)
445 			try_retrans = 1;
446 	}
447 
448 	if (try_retrans)
449 		dn_nsp_output(sk);
450 
451 	return wakeup;
452 }
453 
dn_nsp_send_data_ack(struct sock * sk)454 void dn_nsp_send_data_ack(struct sock *sk)
455 {
456 	struct sk_buff *skb = NULL;
457 
458 	if ((skb = dn_alloc_skb(sk, 9, GFP_ATOMIC)) == NULL)
459 		return;
460 
461 	skb_reserve(skb, 9);
462 	dn_mk_ack_header(sk, skb, 0x04, 9, 0);
463 	dn_nsp_send(skb);
464 }
465 
dn_nsp_send_oth_ack(struct sock * sk)466 void dn_nsp_send_oth_ack(struct sock *sk)
467 {
468 	struct sk_buff *skb = NULL;
469 
470 	if ((skb = dn_alloc_skb(sk, 9, GFP_ATOMIC)) == NULL)
471 		return;
472 
473 	skb_reserve(skb, 9);
474 	dn_mk_ack_header(sk, skb, 0x14, 9, 1);
475 	dn_nsp_send(skb);
476 }
477 
478 
dn_send_conn_ack(struct sock * sk)479 void dn_send_conn_ack (struct sock *sk)
480 {
481 	struct dn_scp *scp = DN_SK(sk);
482 	struct sk_buff *skb = NULL;
483 	struct nsp_conn_ack_msg *msg;
484 
485 	if ((skb = dn_alloc_skb(sk, 3, sk->sk_allocation)) == NULL)
486 		return;
487 
488 	msg = (struct nsp_conn_ack_msg *)skb_put(skb, 3);
489 	msg->msgflg = 0x24;
490 	msg->dstaddr = scp->addrrem;
491 
492 	dn_nsp_send(skb);
493 }
494 
dn_nsp_delayed_ack(struct sock * sk)495 void dn_nsp_delayed_ack(struct sock *sk)
496 {
497 	struct dn_scp *scp = DN_SK(sk);
498 
499 	if (scp->ackxmt_oth != scp->numoth_rcv)
500 		dn_nsp_send_oth_ack(sk);
501 
502 	if (scp->ackxmt_dat != scp->numdat_rcv)
503 		dn_nsp_send_data_ack(sk);
504 }
505 
dn_nsp_retrans_conn_conf(struct sock * sk)506 static int dn_nsp_retrans_conn_conf(struct sock *sk)
507 {
508 	struct dn_scp *scp = DN_SK(sk);
509 
510 	if (scp->state == DN_CC)
511 		dn_send_conn_conf(sk, GFP_ATOMIC);
512 
513 	return 0;
514 }
515 
dn_send_conn_conf(struct sock * sk,gfp_t gfp)516 void dn_send_conn_conf(struct sock *sk, gfp_t gfp)
517 {
518 	struct dn_scp *scp = DN_SK(sk);
519 	struct sk_buff *skb = NULL;
520 	struct nsp_conn_init_msg *msg;
521 	__u8 len = (__u8)le16_to_cpu(scp->conndata_out.opt_optl);
522 
523 	if ((skb = dn_alloc_skb(sk, 50 + len, gfp)) == NULL)
524 		return;
525 
526 	msg = (struct nsp_conn_init_msg *)skb_put(skb, sizeof(*msg));
527 	msg->msgflg = 0x28;
528 	msg->dstaddr = scp->addrrem;
529 	msg->srcaddr = scp->addrloc;
530 	msg->services = scp->services_loc;
531 	msg->info = scp->info_loc;
532 	msg->segsize = cpu_to_le16(scp->segsize_loc);
533 
534 	*skb_put(skb,1) = len;
535 
536 	if (len > 0)
537 		memcpy(skb_put(skb, len), scp->conndata_out.opt_data, len);
538 
539 
540 	dn_nsp_send(skb);
541 
542 	scp->persist = dn_nsp_persist(sk);
543 	scp->persist_fxn = dn_nsp_retrans_conn_conf;
544 }
545 
546 
dn_nsp_do_disc(struct sock * sk,unsigned char msgflg,unsigned short reason,gfp_t gfp,struct dst_entry * dst,int ddl,unsigned char * dd,__le16 rem,__le16 loc)547 static __inline__ void dn_nsp_do_disc(struct sock *sk, unsigned char msgflg,
548 			unsigned short reason, gfp_t gfp,
549 			struct dst_entry *dst,
550 			int ddl, unsigned char *dd, __le16 rem, __le16 loc)
551 {
552 	struct sk_buff *skb = NULL;
553 	int size = 7 + ddl + ((msgflg == NSP_DISCINIT) ? 1 : 0);
554 	unsigned char *msg;
555 
556 	if ((dst == NULL) || (rem == 0)) {
557 		if (net_ratelimit())
558 			printk(KERN_DEBUG "DECnet: dn_nsp_do_disc: BUG! Please report this to SteveW@ACM.org rem=%u dst=%p\n", le16_to_cpu(rem), dst);
559 		return;
560 	}
561 
562 	if ((skb = dn_alloc_skb(sk, size, gfp)) == NULL)
563 		return;
564 
565 	msg = skb_put(skb, size);
566 	*msg++ = msgflg;
567 	*(__le16 *)msg = rem;
568 	msg += 2;
569 	*(__le16 *)msg = loc;
570 	msg += 2;
571 	*(__le16 *)msg = cpu_to_le16(reason);
572 	msg += 2;
573 	if (msgflg == NSP_DISCINIT)
574 		*msg++ = ddl;
575 
576 	if (ddl) {
577 		memcpy(msg, dd, ddl);
578 	}
579 
580 	/*
581 	 * This doesn't go via the dn_nsp_send() function since we need
582 	 * to be able to send disc packets out which have no socket
583 	 * associations.
584 	 */
585 	skb_dst_set(skb, dst_clone(dst));
586 	dst_output(skb);
587 }
588 
589 
dn_nsp_send_disc(struct sock * sk,unsigned char msgflg,unsigned short reason,gfp_t gfp)590 void dn_nsp_send_disc(struct sock *sk, unsigned char msgflg,
591 			unsigned short reason, gfp_t gfp)
592 {
593 	struct dn_scp *scp = DN_SK(sk);
594 	int ddl = 0;
595 
596 	if (msgflg == NSP_DISCINIT)
597 		ddl = le16_to_cpu(scp->discdata_out.opt_optl);
598 
599 	if (reason == 0)
600 		reason = le16_to_cpu(scp->discdata_out.opt_status);
601 
602 	dn_nsp_do_disc(sk, msgflg, reason, gfp, sk->sk_dst_cache, ddl,
603 		scp->discdata_out.opt_data, scp->addrrem, scp->addrloc);
604 }
605 
606 
dn_nsp_return_disc(struct sk_buff * skb,unsigned char msgflg,unsigned short reason)607 void dn_nsp_return_disc(struct sk_buff *skb, unsigned char msgflg,
608 			unsigned short reason)
609 {
610 	struct dn_skb_cb *cb = DN_SKB_CB(skb);
611 	int ddl = 0;
612 	gfp_t gfp = GFP_ATOMIC;
613 
614 	dn_nsp_do_disc(NULL, msgflg, reason, gfp, skb_dst(skb), ddl,
615 			NULL, cb->src_port, cb->dst_port);
616 }
617 
618 
dn_nsp_send_link(struct sock * sk,unsigned char lsflags,char fcval)619 void dn_nsp_send_link(struct sock *sk, unsigned char lsflags, char fcval)
620 {
621 	struct dn_scp *scp = DN_SK(sk);
622 	struct sk_buff *skb;
623 	unsigned char *ptr;
624 	gfp_t gfp = GFP_ATOMIC;
625 
626 	if ((skb = dn_alloc_skb(sk, DN_MAX_NSP_DATA_HEADER + 2, gfp)) == NULL)
627 		return;
628 
629 	skb_reserve(skb, DN_MAX_NSP_DATA_HEADER);
630 	ptr = skb_put(skb, 2);
631 	DN_SKB_CB(skb)->nsp_flags = 0x10;
632 	*ptr++ = lsflags;
633 	*ptr = fcval;
634 
635 	dn_nsp_queue_xmit(sk, skb, gfp, 1);
636 
637 	scp->persist = dn_nsp_persist(sk);
638 	scp->persist_fxn = dn_nsp_xmit_timeout;
639 }
640 
dn_nsp_retrans_conninit(struct sock * sk)641 static int dn_nsp_retrans_conninit(struct sock *sk)
642 {
643 	struct dn_scp *scp = DN_SK(sk);
644 
645 	if (scp->state == DN_CI)
646 		dn_nsp_send_conninit(sk, NSP_RCI);
647 
648 	return 0;
649 }
650 
dn_nsp_send_conninit(struct sock * sk,unsigned char msgflg)651 void dn_nsp_send_conninit(struct sock *sk, unsigned char msgflg)
652 {
653 	struct dn_scp *scp = DN_SK(sk);
654 	struct nsp_conn_init_msg *msg;
655 	unsigned char aux;
656 	unsigned char menuver;
657 	struct dn_skb_cb *cb;
658 	unsigned char type = 1;
659 	gfp_t allocation = (msgflg == NSP_CI) ? sk->sk_allocation : GFP_ATOMIC;
660 	struct sk_buff *skb = dn_alloc_skb(sk, 200, allocation);
661 
662 	if (!skb)
663 		return;
664 
665 	cb  = DN_SKB_CB(skb);
666 	msg = (struct nsp_conn_init_msg *)skb_put(skb,sizeof(*msg));
667 
668 	msg->msgflg	= msgflg;
669 	msg->dstaddr	= 0x0000;		/* Remote Node will assign it*/
670 
671 	msg->srcaddr	= scp->addrloc;
672 	msg->services	= scp->services_loc;	/* Requested flow control    */
673 	msg->info	= scp->info_loc;	/* Version Number            */
674 	msg->segsize	= cpu_to_le16(scp->segsize_loc);	/* Max segment size  */
675 
676 	if (scp->peer.sdn_objnum)
677 		type = 0;
678 
679 	skb_put(skb, dn_sockaddr2username(&scp->peer,
680 					  skb_tail_pointer(skb), type));
681 	skb_put(skb, dn_sockaddr2username(&scp->addr,
682 					  skb_tail_pointer(skb), 2));
683 
684 	menuver = DN_MENUVER_ACC | DN_MENUVER_USR;
685 	if (scp->peer.sdn_flags & SDF_PROXY)
686 		menuver |= DN_MENUVER_PRX;
687 	if (scp->peer.sdn_flags & SDF_UICPROXY)
688 		menuver |= DN_MENUVER_UIC;
689 
690 	*skb_put(skb, 1) = menuver;	/* Menu Version		*/
691 
692 	aux = scp->accessdata.acc_userl;
693 	*skb_put(skb, 1) = aux;
694 	if (aux > 0)
695 		memcpy(skb_put(skb, aux), scp->accessdata.acc_user, aux);
696 
697 	aux = scp->accessdata.acc_passl;
698 	*skb_put(skb, 1) = aux;
699 	if (aux > 0)
700 		memcpy(skb_put(skb, aux), scp->accessdata.acc_pass, aux);
701 
702 	aux = scp->accessdata.acc_accl;
703 	*skb_put(skb, 1) = aux;
704 	if (aux > 0)
705 		memcpy(skb_put(skb, aux), scp->accessdata.acc_acc, aux);
706 
707 	aux = (__u8)le16_to_cpu(scp->conndata_out.opt_optl);
708 	*skb_put(skb, 1) = aux;
709 	if (aux > 0)
710 		memcpy(skb_put(skb, aux), scp->conndata_out.opt_data, aux);
711 
712 	scp->persist = dn_nsp_persist(sk);
713 	scp->persist_fxn = dn_nsp_retrans_conninit;
714 
715 	cb->rt_flags = DN_RT_F_RQR;
716 
717 	dn_nsp_send(skb);
718 }
719 
720