dn_nsp_out.c 17.5 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720
/*
 * DECnet       An implementation of the DECnet protocol suite for the LINUX
 *              operating system.  DECnet is implemented using the  BSD Socket
 *              interface as the means of communication with the user level.
 *
 *              DECnet Network Services Protocol (Output)
 *
 * Author:      Eduardo Marcelo Serrat <emserrat@geocities.com>
 *
 * Changes:
 *
 *    Steve Whitehouse:  Split into dn_nsp_in.c and dn_nsp_out.c from
 *                       original dn_nsp.c.
 *    Steve Whitehouse:  Updated to work with my new routing architecture.
 *    Steve Whitehouse:  Added changes from Eduardo Serrat's patches.
 *    Steve Whitehouse:  Now conninits have the "return" bit set.
 *    Steve Whitehouse:  Fixes to check alloc'd skbs are non NULL!
 *                       Moved output state machine into one function
 *    Steve Whitehouse:  New output state machine
 *         Paul Koning:  Connect Confirm message fix.
 *      Eduardo Serrat:  Fix to stop dn_nsp_do_disc() sending malformed packets.
 *    Steve Whitehouse:  dn_nsp_output() and friends needed a spring clean
 *    Steve Whitehouse:  Moved dn_nsp_send() in here from route.h
 */

/******************************************************************************
    (c) 1995-1998 E.M. Serrat		emserrat@geocities.com

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
*******************************************************************************/

#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/inet.h>
#include <linux/route.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <asm/system.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/termios.h>
#include <linux/interrupt.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/if_packet.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/dn.h>
#include <net/dn_nsp.h>
#include <net/dn_dev.h>
#include <net/dn_route.h>


static int nsp_backoff[NSP_MAXRXTSHIFT + 1] = { 1, 2, 4, 8, 16, 32, 64, 64, 64, 64, 64, 64, 64 };

static void dn_nsp_send(struct sk_buff *skb)
{
	struct sock *sk = skb->sk;
	struct dn_scp *scp = DN_SK(sk);
	struct dst_entry *dst;
	struct flowi fl;

	skb_reset_transport_header(skb);
	scp->stamp = jiffies;

	dst = sk_dst_check(sk, 0);
	if (dst) {
try_again:
		skb_dst_set(skb, dst);
		dst_output(skb);
		return;
	}

	memset(&fl, 0, sizeof(fl));
	fl.oif = sk->sk_bound_dev_if;
	fl.fld_src = dn_saddr2dn(&scp->addr);
	fl.fld_dst = dn_saddr2dn(&scp->peer);
	dn_sk_ports_copy(&fl, scp);
	fl.proto = DNPROTO_NSP;
	if (dn_route_output_sock(&sk->sk_dst_cache, &fl, sk, 0) == 0) {
		dst = sk_dst_get(sk);
		sk->sk_route_caps = dst->dev->features;
		goto try_again;
	}

	sk->sk_err = EHOSTUNREACH;
	if (!sock_flag(sk, SOCK_DEAD))
		sk->sk_state_change(sk);
}


/*
 * If sk == NULL, then we assume that we are supposed to be making
 * a routing layer skb. If sk != NULL, then we are supposed to be
 * creating an skb for the NSP layer.
 *
 * The eventual aim is for each socket to have a cached header size
 * for its outgoing packets, and to set hdr from this when sk != NULL.
 */
struct sk_buff *dn_alloc_skb(struct sock *sk, int size, gfp_t pri)
{
	struct sk_buff *skb;
	int hdr = 64;

	if ((skb = alloc_skb(size + hdr, pri)) == NULL)
		return NULL;

	skb->protocol = htons(ETH_P_DNA_RT);
	skb->pkt_type = PACKET_OUTGOING;

	if (sk)
		skb_set_owner_w(skb, sk);

	skb_reserve(skb, hdr);

	return skb;
}

/*
 * Calculate persist timer based upon the smoothed round
 * trip time and the variance. Backoff according to the
 * nsp_backoff[] array.
 */
unsigned long dn_nsp_persist(struct sock *sk)
{
	struct dn_scp *scp = DN_SK(sk);

	unsigned long t = ((scp->nsp_srtt >> 2) + scp->nsp_rttvar) >> 1;

	t *= nsp_backoff[scp->nsp_rxtshift];

	if (t < HZ) t = HZ;
	if (t > (600*HZ)) t = (600*HZ);

	if (scp->nsp_rxtshift < NSP_MAXRXTSHIFT)
		scp->nsp_rxtshift++;

	/* printk(KERN_DEBUG "rxtshift %lu, t=%lu\n", scp->nsp_rxtshift, t); */

	return t;
}

/*
 * This is called each time we get an estimate for the rtt
 * on the link.
 */
static void dn_nsp_rtt(struct sock *sk, long rtt)
{
	struct dn_scp *scp = DN_SK(sk);
	long srtt = (long)scp->nsp_srtt;
	long rttvar = (long)scp->nsp_rttvar;
	long delta;

	/*
	 * If the jiffies clock flips over in the middle of timestamp
	 * gathering this value might turn out negative, so we make sure
	 * that is it always positive here.
	 */
	if (rtt < 0)
		rtt = -rtt;
	/*
	 * Add new rtt to smoothed average
	 */
	delta = ((rtt << 3) - srtt);
	srtt += (delta >> 3);
	if (srtt >= 1)
		scp->nsp_srtt = (unsigned long)srtt;
	else
		scp->nsp_srtt = 1;

	/*
	 * Add new rtt varience to smoothed varience
	 */
	delta >>= 1;
	rttvar += ((((delta>0)?(delta):(-delta)) - rttvar) >> 2);
	if (rttvar >= 1)
		scp->nsp_rttvar = (unsigned long)rttvar;
	else
		scp->nsp_rttvar = 1;

	/* printk(KERN_DEBUG "srtt=%lu rttvar=%lu\n", scp->nsp_srtt, scp->nsp_rttvar); */
}

/**
 * dn_nsp_clone_and_send - Send a data packet by cloning it
 * @skb: The packet to clone and transmit
 * @gfp: memory allocation flag
 *
 * Clone a queued data or other data packet and transmit it.
 *
 * Returns: The number of times the packet has been sent previously
 */
static inline unsigned dn_nsp_clone_and_send(struct sk_buff *skb,
					     gfp_t gfp)
{
	struct dn_skb_cb *cb = DN_SKB_CB(skb);
	struct sk_buff *skb2;
	int ret = 0;

	if ((skb2 = skb_clone(skb, gfp)) != NULL) {
		ret = cb->xmit_count;
		cb->xmit_count++;
		cb->stamp = jiffies;
		skb2->sk = skb->sk;
		dn_nsp_send(skb2);
	}

	return ret;
}

/**
 * dn_nsp_output - Try and send something from socket queues
 * @sk: The socket whose queues are to be investigated
 *
 * Try and send the packet on the end of the data and other data queues.
 * Other data gets priority over data, and if we retransmit a packet we
 * reduce the window by dividing it in two.
 *
 */
void dn_nsp_output(struct sock *sk)
{
	struct dn_scp *scp = DN_SK(sk);
	struct sk_buff *skb;
	unsigned reduce_win = 0;

	/*
	 * First we check for otherdata/linkservice messages
	 */
	if ((skb = skb_peek(&scp->other_xmit_queue)) != NULL)
		reduce_win = dn_nsp_clone_and_send(skb, GFP_ATOMIC);

	/*
	 * If we may not send any data, we don't.
	 * If we are still trying to get some other data down the
	 * channel, we don't try and send any data.
	 */
	if (reduce_win || (scp->flowrem_sw != DN_SEND))
		goto recalc_window;

	if ((skb = skb_peek(&scp->data_xmit_queue)) != NULL)
		reduce_win = dn_nsp_clone_and_send(skb, GFP_ATOMIC);

	/*
	 * If we've sent any frame more than once, we cut the
	 * send window size in half. There is always a minimum
	 * window size of one available.
	 */
recalc_window:
	if (reduce_win) {
		scp->snd_window >>= 1;
		if (scp->snd_window < NSP_MIN_WINDOW)
			scp->snd_window = NSP_MIN_WINDOW;
	}
}

int dn_nsp_xmit_timeout(struct sock *sk)
{
	struct dn_scp *scp = DN_SK(sk);

	dn_nsp_output(sk);

	if (!skb_queue_empty(&scp->data_xmit_queue) ||
	    !skb_queue_empty(&scp->other_xmit_queue))
		scp->persist = dn_nsp_persist(sk);

	return 0;
}

static inline __le16 *dn_mk_common_header(struct dn_scp *scp, struct sk_buff *skb, unsigned char msgflag, int len)
{
	unsigned char *ptr = skb_push(skb, len);

	BUG_ON(len < 5);

	*ptr++ = msgflag;
	*((__le16 *)ptr) = scp->addrrem;
	ptr += 2;
	*((__le16 *)ptr) = scp->addrloc;
	ptr += 2;
	return (__le16 __force *)ptr;
}

static __le16 *dn_mk_ack_header(struct sock *sk, struct sk_buff *skb, unsigned char msgflag, int hlen, int other)
{
	struct dn_scp *scp = DN_SK(sk);
	unsigned short acknum = scp->numdat_rcv & 0x0FFF;
	unsigned short ackcrs = scp->numoth_rcv & 0x0FFF;
	__le16 *ptr;

	BUG_ON(hlen < 9);

	scp->ackxmt_dat = acknum;
	scp->ackxmt_oth = ackcrs;
	acknum |= 0x8000;
	ackcrs |= 0x8000;

	/* If this is an "other data/ack" message, swap acknum and ackcrs */
	if (other) {
		unsigned short tmp = acknum;
		acknum = ackcrs;
		ackcrs = tmp;
	}

	/* Set "cross subchannel" bit in ackcrs */
	ackcrs |= 0x2000;

	ptr = (__le16 *)dn_mk_common_header(scp, skb, msgflag, hlen);

	*ptr++ = cpu_to_le16(acknum);
	*ptr++ = cpu_to_le16(ackcrs);

	return ptr;
}

static __le16 *dn_nsp_mk_data_header(struct sock *sk, struct sk_buff *skb, int oth)
{
	struct dn_scp *scp = DN_SK(sk);
	struct dn_skb_cb *cb = DN_SKB_CB(skb);
	__le16 *ptr = dn_mk_ack_header(sk, skb, cb->nsp_flags, 11, oth);

	if (unlikely(oth)) {
		cb->segnum = scp->numoth;
		seq_add(&scp->numoth, 1);
	} else {
		cb->segnum = scp->numdat;
		seq_add(&scp->numdat, 1);
	}
	*(ptr++) = cpu_to_le16(cb->segnum);

	return ptr;
}

void dn_nsp_queue_xmit(struct sock *sk, struct sk_buff *skb,
			gfp_t gfp, int oth)
{
	struct dn_scp *scp = DN_SK(sk);
	struct dn_skb_cb *cb = DN_SKB_CB(skb);
	unsigned long t = ((scp->nsp_srtt >> 2) + scp->nsp_rttvar) >> 1;

	cb->xmit_count = 0;
	dn_nsp_mk_data_header(sk, skb, oth);

	/*
	 * Slow start: If we have been idle for more than
	 * one RTT, then reset window to min size.
	 */
	if ((jiffies - scp->stamp) > t)
		scp->snd_window = NSP_MIN_WINDOW;

	if (oth)
		skb_queue_tail(&scp->other_xmit_queue, skb);
	else
		skb_queue_tail(&scp->data_xmit_queue, skb);

	if (scp->flowrem_sw != DN_SEND)
		return;

	dn_nsp_clone_and_send(skb, gfp);
}


int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb, struct sk_buff_head *q, unsigned short acknum)
{
	struct dn_skb_cb *cb = DN_SKB_CB(skb);
	struct dn_scp *scp = DN_SK(sk);
	struct sk_buff *skb2, *n, *ack = NULL;
	int wakeup = 0;
	int try_retrans = 0;
	unsigned long reftime = cb->stamp;
	unsigned long pkttime;
	unsigned short xmit_count;
	unsigned short segnum;

	skb_queue_walk_safe(q, skb2, n) {
		struct dn_skb_cb *cb2 = DN_SKB_CB(skb2);

		if (dn_before_or_equal(cb2->segnum, acknum))
			ack = skb2;

		/* printk(KERN_DEBUG "ack: %s %04x %04x\n", ack ? "ACK" : "SKIP", (int)cb2->segnum, (int)acknum); */

		if (ack == NULL)
			continue;

		/* printk(KERN_DEBUG "check_xmit_queue: %04x, %d\n", acknum, cb2->xmit_count); */

		/* Does _last_ packet acked have xmit_count > 1 */
		try_retrans = 0;
		/* Remember to wake up the sending process */
		wakeup = 1;
		/* Keep various statistics */
		pkttime = cb2->stamp;
		xmit_count = cb2->xmit_count;
		segnum = cb2->segnum;
		/* Remove and drop ack'ed packet */
		skb_unlink(ack, q);
		kfree_skb(ack);
		ack = NULL;

		/*
		 * We don't expect to see acknowledgements for packets we
		 * haven't sent yet.
		 */
		WARN_ON(xmit_count == 0);

		/*
		 * If the packet has only been sent once, we can use it
		 * to calculate the RTT and also open the window a little
		 * further.
		 */
		if (xmit_count == 1) {
			if (dn_equal(segnum, acknum))
				dn_nsp_rtt(sk, (long)(pkttime - reftime));

			if (scp->snd_window < scp->max_window)
				scp->snd_window++;
		}

		/*
		 * Packet has been sent more than once. If this is the last
		 * packet to be acknowledged then we want to send the next
		 * packet in the send queue again (assumes the remote host does
		 * go-back-N error control).
		 */
		if (xmit_count > 1)
			try_retrans = 1;
	}

	if (try_retrans)
		dn_nsp_output(sk);

	return wakeup;
}

void dn_nsp_send_data_ack(struct sock *sk)
{
	struct sk_buff *skb = NULL;

	if ((skb = dn_alloc_skb(sk, 9, GFP_ATOMIC)) == NULL)
		return;

	skb_reserve(skb, 9);
	dn_mk_ack_header(sk, skb, 0x04, 9, 0);
	dn_nsp_send(skb);
}

void dn_nsp_send_oth_ack(struct sock *sk)
{
	struct sk_buff *skb = NULL;

	if ((skb = dn_alloc_skb(sk, 9, GFP_ATOMIC)) == NULL)
		return;

	skb_reserve(skb, 9);
	dn_mk_ack_header(sk, skb, 0x14, 9, 1);
	dn_nsp_send(skb);
}


void dn_send_conn_ack (struct sock *sk)
{
	struct dn_scp *scp = DN_SK(sk);
	struct sk_buff *skb = NULL;
	struct nsp_conn_ack_msg *msg;

	if ((skb = dn_alloc_skb(sk, 3, sk->sk_allocation)) == NULL)
		return;

	msg = (struct nsp_conn_ack_msg *)skb_put(skb, 3);
	msg->msgflg = 0x24;
	msg->dstaddr = scp->addrrem;

	dn_nsp_send(skb);
}

void dn_nsp_delayed_ack(struct sock *sk)
{
	struct dn_scp *scp = DN_SK(sk);

	if (scp->ackxmt_oth != scp->numoth_rcv)
		dn_nsp_send_oth_ack(sk);

	if (scp->ackxmt_dat != scp->numdat_rcv)
		dn_nsp_send_data_ack(sk);
}

static int dn_nsp_retrans_conn_conf(struct sock *sk)
{
	struct dn_scp *scp = DN_SK(sk);

	if (scp->state == DN_CC)
		dn_send_conn_conf(sk, GFP_ATOMIC);

	return 0;
}

void dn_send_conn_conf(struct sock *sk, gfp_t gfp)
{
	struct dn_scp *scp = DN_SK(sk);
	struct sk_buff *skb = NULL;
	struct nsp_conn_init_msg *msg;
	__u8 len = (__u8)le16_to_cpu(scp->conndata_out.opt_optl);

	if ((skb = dn_alloc_skb(sk, 50 + len, gfp)) == NULL)
		return;

	msg = (struct nsp_conn_init_msg *)skb_put(skb, sizeof(*msg));
	msg->msgflg = 0x28;
	msg->dstaddr = scp->addrrem;
	msg->srcaddr = scp->addrloc;
	msg->services = scp->services_loc;
	msg->info = scp->info_loc;
	msg->segsize = cpu_to_le16(scp->segsize_loc);

	*skb_put(skb,1) = len;

	if (len > 0)
		memcpy(skb_put(skb, len), scp->conndata_out.opt_data, len);


	dn_nsp_send(skb);

	scp->persist = dn_nsp_persist(sk);
	scp->persist_fxn = dn_nsp_retrans_conn_conf;
}


static __inline__ void 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)
{
	struct sk_buff *skb = NULL;
	int size = 7 + ddl + ((msgflg == NSP_DISCINIT) ? 1 : 0);
	unsigned char *msg;

	if ((dst == NULL) || (rem == 0)) {
		if (net_ratelimit())
			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);
		return;
	}

	if ((skb = dn_alloc_skb(sk, size, gfp)) == NULL)
		return;

	msg = skb_put(skb, size);
	*msg++ = msgflg;
	*(__le16 *)msg = rem;
	msg += 2;
	*(__le16 *)msg = loc;
	msg += 2;
	*(__le16 *)msg = cpu_to_le16(reason);
	msg += 2;
	if (msgflg == NSP_DISCINIT)
		*msg++ = ddl;

	if (ddl) {
		memcpy(msg, dd, ddl);
	}

	/*
	 * This doesn't go via the dn_nsp_send() function since we need
	 * to be able to send disc packets out which have no socket
	 * associations.
	 */
	skb_dst_set(skb, dst_clone(dst));
	dst_output(skb);
}


void dn_nsp_send_disc(struct sock *sk, unsigned char msgflg,
			unsigned short reason, gfp_t gfp)
{
	struct dn_scp *scp = DN_SK(sk);
	int ddl = 0;

	if (msgflg == NSP_DISCINIT)
		ddl = le16_to_cpu(scp->discdata_out.opt_optl);

	if (reason == 0)
		reason = le16_to_cpu(scp->discdata_out.opt_status);

	dn_nsp_do_disc(sk, msgflg, reason, gfp, sk->sk_dst_cache, ddl,
		scp->discdata_out.opt_data, scp->addrrem, scp->addrloc);
}


void dn_nsp_return_disc(struct sk_buff *skb, unsigned char msgflg,
			unsigned short reason)
{
	struct dn_skb_cb *cb = DN_SKB_CB(skb);
	int ddl = 0;
	gfp_t gfp = GFP_ATOMIC;

	dn_nsp_do_disc(NULL, msgflg, reason, gfp, skb_dst(skb), ddl,
			NULL, cb->src_port, cb->dst_port);
}


void dn_nsp_send_link(struct sock *sk, unsigned char lsflags, char fcval)
{
	struct dn_scp *scp = DN_SK(sk);
	struct sk_buff *skb;
	unsigned char *ptr;
	gfp_t gfp = GFP_ATOMIC;

	if ((skb = dn_alloc_skb(sk, DN_MAX_NSP_DATA_HEADER + 2, gfp)) == NULL)
		return;

	skb_reserve(skb, DN_MAX_NSP_DATA_HEADER);
	ptr = skb_put(skb, 2);
	DN_SKB_CB(skb)->nsp_flags = 0x10;
	*ptr++ = lsflags;
	*ptr = fcval;

	dn_nsp_queue_xmit(sk, skb, gfp, 1);

	scp->persist = dn_nsp_persist(sk);
	scp->persist_fxn = dn_nsp_xmit_timeout;
}

static int dn_nsp_retrans_conninit(struct sock *sk)
{
	struct dn_scp *scp = DN_SK(sk);

	if (scp->state == DN_CI)
		dn_nsp_send_conninit(sk, NSP_RCI);

	return 0;
}

void dn_nsp_send_conninit(struct sock *sk, unsigned char msgflg)
{
	struct dn_scp *scp = DN_SK(sk);
	struct nsp_conn_init_msg *msg;
	unsigned char aux;
	unsigned char menuver;
	struct dn_skb_cb *cb;
	unsigned char type = 1;
	gfp_t allocation = (msgflg == NSP_CI) ? sk->sk_allocation : GFP_ATOMIC;
	struct sk_buff *skb = dn_alloc_skb(sk, 200, allocation);

	if (!skb)
		return;

	cb  = DN_SKB_CB(skb);
	msg = (struct nsp_conn_init_msg *)skb_put(skb,sizeof(*msg));

	msg->msgflg	= msgflg;
	msg->dstaddr	= 0x0000;		/* Remote Node will assign it*/

	msg->srcaddr	= scp->addrloc;
	msg->services	= scp->services_loc;	/* Requested flow control    */
	msg->info	= scp->info_loc;	/* Version Number            */
	msg->segsize	= cpu_to_le16(scp->segsize_loc);	/* Max segment size  */

	if (scp->peer.sdn_objnum)
		type = 0;

	skb_put(skb, dn_sockaddr2username(&scp->peer,
					  skb_tail_pointer(skb), type));
	skb_put(skb, dn_sockaddr2username(&scp->addr,
					  skb_tail_pointer(skb), 2));

	menuver = DN_MENUVER_ACC | DN_MENUVER_USR;
	if (scp->peer.sdn_flags & SDF_PROXY)
		menuver |= DN_MENUVER_PRX;
	if (scp->peer.sdn_flags & SDF_UICPROXY)
		menuver |= DN_MENUVER_UIC;

	*skb_put(skb, 1) = menuver;	/* Menu Version		*/

	aux = scp->accessdata.acc_userl;
	*skb_put(skb, 1) = aux;
	if (aux > 0)
	memcpy(skb_put(skb, aux), scp->accessdata.acc_user, aux);

	aux = scp->accessdata.acc_passl;
	*skb_put(skb, 1) = aux;
	if (aux > 0)
	memcpy(skb_put(skb, aux), scp->accessdata.acc_pass, aux);

	aux = scp->accessdata.acc_accl;
	*skb_put(skb, 1) = aux;
	if (aux > 0)
	memcpy(skb_put(skb, aux), scp->accessdata.acc_acc, aux);

	aux = (__u8)le16_to_cpu(scp->conndata_out.opt_optl);
	*skb_put(skb, 1) = aux;
	if (aux > 0)
	memcpy(skb_put(skb,aux), scp->conndata_out.opt_data, aux);

	scp->persist = dn_nsp_persist(sk);
	scp->persist_fxn = dn_nsp_retrans_conninit;

	cb->rt_flags = DN_RT_F_RQR;

	dn_nsp_send(skb);
}