ipv6.c 26.8 KB
Newer Older
L
Linus Torvalds 已提交
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
/* SCTP kernel reference Implementation
 * (C) Copyright IBM Corp. 2002, 2004
 * Copyright (c) 2001 Nokia, Inc.
 * Copyright (c) 2001 La Monte H.P. Yarroll
 * Copyright (c) 2002-2003 Intel Corp.
 *
 * This file is part of the SCTP kernel reference Implementation
 *
 * SCTP over IPv6.
 *
 * The SCTP reference implementation 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, or (at your option)
 * any later version.
 *
 * The SCTP reference implementation 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU CC; see the file COPYING.  If not, write to
 * the Free Software Foundation, 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * Please send any bug reports or fixes you make to the
 * email address(es):
 *    lksctp developers <lksctp-developers@lists.sourceforge.net>
 *
 * Or submit a bug report through the following website:
 *    http://www.sf.net/projects/lksctp
 *
 * Written or modified by:
 *    Le Yanqun		    <yanqun.le@nokia.com>
 *    Hui Huang		    <hui.huang@nokia.com>
 *    La Monte H.P. Yarroll <piggy@acm.org>
 *    Sridhar Samudrala	    <sri@us.ibm.com>
 *    Jon Grimm		    <jgrimm@us.ibm.com>
 *    Ardelle Fan	    <ardelle.fan@intel.com>
 *
 * Based on:
 *	linux/net/ipv6/tcp_ipv6.c
 *
 * Any bugs reported given to us we will try to fix... any fixes shared will
 * be incorporated into the next SCTP release.
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/sched.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/netdevice.h>
#include <linux/init.h>
#include <linux/ipsec.h>

#include <linux/ipv6.h>
#include <linux/icmpv6.h>
#include <linux/random.h>
#include <linux/seq_file.h>

#include <net/protocol.h>
#include <net/ndisc.h>
70
#include <net/ip.h>
L
Linus Torvalds 已提交
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
#include <net/ipv6.h>
#include <net/transp_v6.h>
#include <net/addrconf.h>
#include <net/ip6_route.h>
#include <net/inet_common.h>
#include <net/inet_ecn.h>
#include <net/sctp/sctp.h>

#include <asm/uaccess.h>

extern int sctp_inetaddr_event(struct notifier_block *, unsigned long, void *);
static struct notifier_block sctp_inet6addr_notifier = {
	.notifier_call = sctp_inetaddr_event,
};

/* ICMP error handler. */
SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
			     int type, int code, int offset, __u32 info)
{
	struct inet6_dev *idev;
	struct ipv6hdr *iph = (struct ipv6hdr *)skb->data;
	struct sctphdr *sh = (struct sctphdr *)(skb->data + offset);
	struct sock *sk;
	struct sctp_association *asoc;
	struct sctp_transport *transport;
	struct ipv6_pinfo *np;
	char *saveip, *savesctp;
	int err;

	idev = in6_dev_get(skb->dev);

	/* Fix up skb to look at the embedded net header. */
	saveip = skb->nh.raw;
	savesctp  = skb->h.raw;
	skb->nh.ipv6h = iph;
	skb->h.raw = (char *)sh;
107
	sk = sctp_err_lookup(AF_INET6, skb, sh, &asoc, &transport);
L
Linus Torvalds 已提交
108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125
	/* Put back, the original pointers. */
	skb->nh.raw = saveip;
	skb->h.raw = savesctp;
	if (!sk) {
		ICMP6_INC_STATS_BH(idev, ICMP6_MIB_INERRORS);
		goto out;
	}

	/* Warning:  The sock lock is held.  Remember to call
	 * sctp_err_finish!
	 */

	switch (type) {
	case ICMPV6_PKT_TOOBIG:
		sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
		goto out_unlock;
	case ICMPV6_PARAMPROB:
		if (ICMPV6_UNK_NEXTHDR == code) {
126
			sctp_icmp_proto_unreachable(sk, asoc, transport);
L
Linus Torvalds 已提交
127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143
			goto out_unlock;
		}
		break;
	default:
		break;
	}

	np = inet6_sk(sk);
	icmpv6_err_convert(type, code, &err);
	if (!sock_owned_by_user(sk) && np->recverr) {
		sk->sk_err = err;
		sk->sk_error_report(sk);
	} else {  /* Only an error on timeout */
		sk->sk_err_soft = err;
	}

out_unlock:
144
	sctp_err_finish(sk, asoc);
L
Linus Torvalds 已提交
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
out:
	if (likely(idev != NULL))
		in6_dev_put(idev);
}

/* Based on tcp_v6_xmit() in tcp_ipv6.c. */
static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport,
			int ipfragok)
{
	struct sock *sk = skb->sk;
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct flowi fl;

	memset(&fl, 0, sizeof(fl));

	fl.proto = sk->sk_protocol;

	/* Fill in the dest address from the route entry passed with the skb
	 * and the source address from the transport.
	 */
	ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
	ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);

	fl.fl6_flowlabel = np->flow_label;
	IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
	if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
		fl.oif = transport->saddr.v6.sin6_scope_id;
	else
		fl.oif = sk->sk_bound_dev_if;
	fl.fl_ip_sport = inet_sk(sk)->sport;
	fl.fl_ip_dport = transport->ipaddr.v6.sin6_port;

	if (np->opt && np->opt->srcrt) {
		struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
		ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
	}

	SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
J
Joe Perches 已提交
183
			  "src:" NIP6_FMT " dst:" NIP6_FMT "\n",
L
Linus Torvalds 已提交
184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207
			  __FUNCTION__, skb, skb->len,
			  NIP6(fl.fl6_src), NIP6(fl.fl6_dst));

	SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);

	return ip6_xmit(sk, skb, &fl, np->opt, ipfragok);
}

/* Returns the dst cache entry for the given source and destination ip
 * addresses.
 */
static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
					 union sctp_addr *daddr,
					 union sctp_addr *saddr)
{
	struct dst_entry *dst;
	struct flowi fl;

	memset(&fl, 0, sizeof(fl));
	ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
	if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
		fl.oif = daddr->v6.sin6_scope_id;
	

J
Joe Perches 已提交
208
	SCTP_DEBUG_PRINTK("%s: DST=" NIP6_FMT " ",
L
Linus Torvalds 已提交
209 210 211 212 213
			  __FUNCTION__, NIP6(fl.fl6_dst));

	if (saddr) {
		ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
		SCTP_DEBUG_PRINTK(
J
Joe Perches 已提交
214
			"SRC=" NIP6_FMT " - ",
L
Linus Torvalds 已提交
215 216 217 218 219 220 221 222
			NIP6(fl.fl6_src));
	}

	dst = ip6_route_output(NULL, &fl);
	if (dst) {
		struct rt6_info *rt;
		rt = (struct rt6_info *)dst;
		SCTP_DEBUG_PRINTK(
J
Joe Perches 已提交
223
			"rt6_dst:" NIP6_FMT " rt6_src:" NIP6_FMT "\n",
L
Linus Torvalds 已提交
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
			NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
	} else {
		SCTP_DEBUG_PRINTK("NO ROUTE\n");
	}

	return dst;
}

/* Returns the number of consecutive initial bits that match in the 2 ipv6
 * addresses.
 */
static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
					 union sctp_addr *s2)
{
	struct in6_addr *a1 = &s1->v6.sin6_addr;
	struct in6_addr *a2 = &s2->v6.sin6_addr;
	int i, j;

	for (i = 0; i < 4 ; i++) {
		__u32 a1xora2;

		a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];

		if ((j = fls(ntohl(a1xora2))))
			return (i * 32 + 32 - j);
	}

	return (i*32);
}

/* Fills in the source address(saddr) based on the destination address(daddr)
 * and asoc's bind address list.
 */
static void sctp_v6_get_saddr(struct sctp_association *asoc,
			      struct dst_entry *dst,
			      union sctp_addr *daddr,
			      union sctp_addr *saddr)
{
	struct sctp_bind_addr *bp;
	rwlock_t *addr_lock;
	struct sctp_sockaddr_entry *laddr;
	struct list_head *pos;
	sctp_scope_t scope;
	union sctp_addr *baddr = NULL;
	__u8 matchlen = 0;
	__u8 bmatchlen;

	SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
J
Joe Perches 已提交
272
			  "daddr:" NIP6_FMT " ",
L
Linus Torvalds 已提交
273 274 275 276
			  __FUNCTION__, asoc, dst, NIP6(daddr->v6.sin6_addr));

	if (!asoc) {
		ipv6_get_saddr(dst, &daddr->v6.sin6_addr,&saddr->v6.sin6_addr);
J
Joe Perches 已提交
277
		SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: " NIP6_FMT "\n",
L
Linus Torvalds 已提交
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
				  NIP6(saddr->v6.sin6_addr));
		return;
	}

	scope = sctp_scope(daddr);

	bp = &asoc->base.bind_addr;
	addr_lock = &asoc->base.addr_lock;

	/* Go through the bind address list and find the best source address
	 * that matches the scope of the destination address.
	 */
	sctp_read_lock(addr_lock);
	list_for_each(pos, &bp->address_list) {
		laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
		if ((laddr->a.sa.sa_family == AF_INET6) &&
		    (scope <= sctp_scope(&laddr->a))) {
			bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
			if (!baddr || (matchlen < bmatchlen)) {
				baddr = &laddr->a;
				matchlen = bmatchlen;
			}
		}
	}

	if (baddr) {
		memcpy(saddr, baddr, sizeof(union sctp_addr));
J
Joe Perches 已提交
305
		SCTP_DEBUG_PRINTK("saddr: " NIP6_FMT "\n",
L
Linus Torvalds 已提交
306 307 308
				  NIP6(saddr->v6.sin6_addr));
	} else {
		printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
J
Joe Perches 已提交
309
		       "address for the dest:" NIP6_FMT "\n",
L
Linus Torvalds 已提交
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
		       __FUNCTION__, asoc, NIP6(daddr->v6.sin6_addr));
	}

	sctp_read_unlock(addr_lock);
}

/* Make a copy of all potential local addresses. */
static void sctp_v6_copy_addrlist(struct list_head *addrlist,
				  struct net_device *dev)
{
	struct inet6_dev *in6_dev;
	struct inet6_ifaddr *ifp;
	struct sctp_sockaddr_entry *addr;

	read_lock(&addrconf_lock);
	if ((in6_dev = __in6_dev_get(dev)) == NULL) {
		read_unlock(&addrconf_lock);
		return;
	}

	read_lock(&in6_dev->lock);
	for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
		/* Add the address to the local list.  */
		addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
		if (addr) {
			addr->a.v6.sin6_family = AF_INET6;
			addr->a.v6.sin6_port = 0;
			addr->a.v6.sin6_addr = ifp->addr;
			addr->a.v6.sin6_scope_id = dev->ifindex;
			INIT_LIST_HEAD(&addr->list);
			list_add_tail(&addr->list, addrlist);
		}
	}

	read_unlock(&in6_dev->lock);
	read_unlock(&addrconf_lock);
}

/* Initialize a sockaddr_storage from in incoming skb. */
static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
			     int is_saddr)
{
	void *from;
	__u16 *port;
	struct sctphdr *sh;

	port = &addr->v6.sin6_port;
	addr->v6.sin6_family = AF_INET6;
	addr->v6.sin6_flowinfo = 0; /* FIXME */
	addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;

	sh = (struct sctphdr *) skb->h.raw;
	if (is_saddr) {
		*port  = ntohs(sh->source);
		from = &skb->nh.ipv6h->saddr;
	} else {
		*port = ntohs(sh->dest);
		from = &skb->nh.ipv6h->daddr;
	}
	ipv6_addr_copy(&addr->v6.sin6_addr, from);
}

/* Initialize an sctp_addr from a socket. */
static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
{
	addr->v6.sin6_family = AF_INET6;
	addr->v6.sin6_port = inet_sk(sk)->num;
	addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
}

/* Initialize sk->sk_rcv_saddr from sctp_addr. */
static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
{
	if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
		inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
		inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
		inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
		inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
			addr->v4.sin_addr.s_addr;
	} else {
		inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
	}
}

/* Initialize sk->sk_daddr from sctp_addr. */
static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
{
	if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
		inet6_sk(sk)->daddr.s6_addr32[0] = 0;
		inet6_sk(sk)->daddr.s6_addr32[1] = 0;
		inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
		inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
	} else {
		inet6_sk(sk)->daddr = addr->v6.sin6_addr;
	}
}

/* Initialize a sctp_addr from an address parameter. */
static void sctp_v6_from_addr_param(union sctp_addr *addr,
				    union sctp_addr_param *param,
				    __u16 port, int iif)
{
	addr->v6.sin6_family = AF_INET6;
	addr->v6.sin6_port = port;
	addr->v6.sin6_flowinfo = 0; /* BUG */
	ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
	addr->v6.sin6_scope_id = iif;
}

/* Initialize an address parameter from a sctp_addr and return the length
 * of the address parameter.
 */
static int sctp_v6_to_addr_param(const union sctp_addr *addr,
				 union sctp_addr_param *param)
{
	int length = sizeof(sctp_ipv6addr_param_t);

	param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
	param->v6.param_hdr.length = ntohs(length);
	ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);

	return length;
}

/* Initialize a sctp_addr from a dst_entry. */
static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
			      unsigned short port)
{
	struct rt6_info *rt = (struct rt6_info *)dst;
	addr->sa.sa_family = AF_INET6;
	addr->v6.sin6_port = port;
	ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
}

/* Compare addresses exactly.
 * v4-mapped-v6 is also in consideration.
 */
static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
			    const union sctp_addr *addr2)
{
	if (addr1->sa.sa_family != addr2->sa.sa_family) {
		if (addr1->sa.sa_family == AF_INET &&
		    addr2->sa.sa_family == AF_INET6 &&
		    IPV6_ADDR_MAPPED == ipv6_addr_type(&addr2->v6.sin6_addr)) {
			if (addr2->v6.sin6_port == addr1->v4.sin_port &&
			    addr2->v6.sin6_addr.s6_addr32[3] ==
			    addr1->v4.sin_addr.s_addr)
				return 1;
		}
		if (addr2->sa.sa_family == AF_INET &&
		    addr1->sa.sa_family == AF_INET6 &&
		    IPV6_ADDR_MAPPED == ipv6_addr_type(&addr1->v6.sin6_addr)) {
			if (addr1->v6.sin6_port == addr2->v4.sin_port &&
			    addr1->v6.sin6_addr.s6_addr32[3] ==
			    addr2->v4.sin_addr.s_addr)
				return 1;
		}
		return 0;
	}
	if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
		return 0;
	/* If this is a linklocal address, compare the scope_id. */
	if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
		if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
		    (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
			return 0;
		}
	}

	return 1;
}

/* Initialize addr struct to INADDR_ANY. */
static void sctp_v6_inaddr_any(union sctp_addr *addr, unsigned short port)
{
	memset(addr, 0x00, sizeof(union sctp_addr));
	addr->v6.sin6_family = AF_INET6;
	addr->v6.sin6_port = port;
}

/* Is this a wildcard address? */
static int sctp_v6_is_any(const union sctp_addr *addr)
{
493
	return ipv6_addr_any(&addr->v6.sin6_addr);
L
Linus Torvalds 已提交
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
}

/* Should this be available for binding?   */
static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
{
	int type;
	struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;

	type = ipv6_addr_type(in6);
	if (IPV6_ADDR_ANY == type)
		return 1;
	if (type == IPV6_ADDR_MAPPED) {
		if (sp && !sp->v4mapped)
			return 0;
		if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
			return 0;
		sctp_v6_map_v4(addr);
		return sctp_get_af_specific(AF_INET)->available(addr, sp);
	}
	if (!(type & IPV6_ADDR_UNICAST))
		return 0;

	return ipv6_chk_addr(in6, NULL, 0);
}

/* This function checks if the address is a valid address to be used for
 * SCTP.
 *
 * Output:
 * Return 0 - If the address is a non-unicast or an illegal address.
 * Return 1 - If the address is a unicast.
 */
static int sctp_v6_addr_valid(union sctp_addr *addr, struct sctp_sock *sp)
{
	int ret = ipv6_addr_type(&addr->v6.sin6_addr);

	/* Support v4-mapped-v6 address. */
	if (ret == IPV6_ADDR_MAPPED) {
		/* Note: This routine is used in input, so v4-mapped-v6
		 * are disallowed here when there is no sctp_sock.
		 */
		if (!sp || !sp->v4mapped)
			return 0;
		if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
			return 0;
		sctp_v6_map_v4(addr);
		return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp);
	}

	/* Is this a non-unicast address */
	if (!(ret & IPV6_ADDR_UNICAST))
		return 0;

	return 1;
}

/* What is the scope of 'addr'?  */
static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
{
	int v6scope;
	sctp_scope_t retval;

	/* The IPv6 scope is really a set of bit fields.
	 * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
	 */

	v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
	switch (v6scope) {
	case IFA_HOST:
		retval = SCTP_SCOPE_LOOPBACK;
		break;
	case IFA_LINK:
		retval = SCTP_SCOPE_LINK;
		break;
	case IFA_SITE:
		retval = SCTP_SCOPE_PRIVATE;
		break;
	default:
		retval = SCTP_SCOPE_GLOBAL;
		break;
	};

	return retval;
}

/* Create and initialize a new sk for the socket to be returned by accept(). */
static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
					     struct sctp_association *asoc)
{
	struct inet_sock *inet = inet_sk(sk);
	struct sock *newsk;
	struct inet_sock *newinet;
	struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
	struct sctp6_sock *newsctp6sk;

	newsk = sk_alloc(PF_INET6, GFP_KERNEL, sk->sk_prot, 1);
	if (!newsk)
		goto out;

	sock_init_data(NULL, newsk);

	newsk->sk_type = SOCK_STREAM;

	newsk->sk_prot = sk->sk_prot;
	newsk->sk_no_check = sk->sk_no_check;
	newsk->sk_reuse = sk->sk_reuse;

	newsk->sk_destruct = inet_sock_destruct;
	newsk->sk_family = PF_INET6;
	newsk->sk_protocol = IPPROTO_SCTP;
	newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
	newsk->sk_shutdown = sk->sk_shutdown;
	sock_reset_flag(sk, SOCK_ZAPPED);

	newsctp6sk = (struct sctp6_sock *)newsk;
	inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;

	newinet = inet_sk(newsk);
	newnp = inet6_sk(newsk);

	memcpy(newnp, np, sizeof(struct ipv6_pinfo));

	/* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
	 * and getpeername().
	 */
	newinet->sport = inet->sport;
	newnp->saddr = np->saddr;
	newnp->rcv_saddr = np->rcv_saddr;
	newinet->dport = htons(asoc->peer.port);
	sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);

	/* Init the ipv4 part of the socket since we can have sockets
	 * using v6 API for ipv4.
	 */
	newinet->uc_ttl = -1;
	newinet->mc_loop = 1;
	newinet->mc_ttl = 1;
	newinet->mc_index = 0;
	newinet->mc_list = NULL;

	if (ipv4_config.no_pmtu_disc)
		newinet->pmtudisc = IP_PMTUDISC_DONT;
	else
		newinet->pmtudisc = IP_PMTUDISC_WANT;

639
	sk_refcnt_debug_inc(newsk);
L
Linus Torvalds 已提交
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

	if (newsk->sk_prot->init(newsk)) {
		sk_common_release(newsk);
		newsk = NULL;
	}

out:
	return newsk;
}

/* Map v4 address to mapped v6 address */
static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
{
	if (sp->v4mapped && AF_INET == addr->sa.sa_family)
		sctp_v4_map_v6(addr);
}

/* Where did this skb come from?  */
static int sctp_v6_skb_iif(const struct sk_buff *skb)
{
	struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
	return opt->iif;
}

/* Was this packet marked by Explicit Congestion Notification? */
static int sctp_v6_is_ce(const struct sk_buff *skb)
{
	return *((__u32 *)(skb->nh.ipv6h)) & htonl(1<<20);
}

/* Dump the v6 addr to the seq file. */
static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
{
J
Joe Perches 已提交
673
	seq_printf(seq, NIP6_FMT " ", NIP6(addr->v6.sin6_addr));
L
Linus Torvalds 已提交
674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805
}

/* Initialize a PF_INET6 socket msg_name. */
static void sctp_inet6_msgname(char *msgname, int *addr_len)
{
	struct sockaddr_in6 *sin6;

	sin6 = (struct sockaddr_in6 *)msgname;
	sin6->sin6_family = AF_INET6;
	sin6->sin6_flowinfo = 0;
	sin6->sin6_scope_id = 0; /*FIXME */
	*addr_len = sizeof(struct sockaddr_in6);
}

/* Initialize a PF_INET msgname from a ulpevent. */
static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
				     char *msgname, int *addrlen)
{
	struct sockaddr_in6 *sin6, *sin6from;

	if (msgname) {
		union sctp_addr *addr;
		struct sctp_association *asoc;

		asoc = event->asoc;
		sctp_inet6_msgname(msgname, addrlen);
		sin6 = (struct sockaddr_in6 *)msgname;
		sin6->sin6_port = htons(asoc->peer.port);
		addr = &asoc->peer.primary_addr;

		/* Note: If we go to a common v6 format, this code
		 * will change.
		 */

		/* Map ipv4 address into v4-mapped-on-v6 address.  */
		if (sctp_sk(asoc->base.sk)->v4mapped &&
		    AF_INET == addr->sa.sa_family) {
			sctp_v4_map_v6((union sctp_addr *)sin6);
			sin6->sin6_addr.s6_addr32[3] =
				addr->v4.sin_addr.s_addr;
			return;
		}

		sin6from = &asoc->peer.primary_addr.v6;
		ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
		if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
			sin6->sin6_scope_id = sin6from->sin6_scope_id;
	}
}

/* Initialize a msg_name from an inbound skb. */
static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
				   int *addr_len)
{
	struct sctphdr *sh;
	struct sockaddr_in6 *sin6;

	if (msgname) {
		sctp_inet6_msgname(msgname, addr_len);
		sin6 = (struct sockaddr_in6 *)msgname;
		sh = (struct sctphdr *)skb->h.raw;
		sin6->sin6_port = sh->source;

		/* Map ipv4 address into v4-mapped-on-v6 address. */
		if (sctp_sk(skb->sk)->v4mapped &&
		    skb->nh.iph->version == 4) {
			sctp_v4_map_v6((union sctp_addr *)sin6);
			sin6->sin6_addr.s6_addr32[3] = skb->nh.iph->saddr;
			return;
		}

		/* Otherwise, just copy the v6 address. */
		ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr);
		if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
			struct sctp_ulpevent *ev = sctp_skb2event(skb);
			sin6->sin6_scope_id = ev->iif;
		}
	}
}

/* Do we support this AF? */
static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
{
	switch (family) {
	case AF_INET6:
		return 1;
	/* v4-mapped-v6 addresses */
	case AF_INET:
		if (!__ipv6_only_sock(sctp_opt2sk(sp)) && sp->v4mapped)
			return 1;
	default:
		return 0;
	}
}

/* Address matching with wildcards allowed.  This extra level
 * of indirection lets us choose whether a PF_INET6 should
 * disallow any v4 addresses if we so choose.
 */
static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
			       const union sctp_addr *addr2,
			       struct sctp_sock *opt)
{
	struct sctp_af *af1, *af2;

	af1 = sctp_get_af_specific(addr1->sa.sa_family);
	af2 = sctp_get_af_specific(addr2->sa.sa_family);

	if (!af1 || !af2)
		return 0;
	/* Today, wildcard AF_INET/AF_INET6. */
	if (sctp_is_any(addr1) || sctp_is_any(addr2))
		return 1;

	if (addr1->sa.sa_family != addr2->sa.sa_family)
		return 0;

	return af1->cmp_addr(addr1, addr2);
}

/* Verify that the provided sockaddr looks bindable.   Common verification,
 * has already been taken care of.
 */
static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
{
	struct sctp_af *af;

	/* ASSERT: address family has already been verified. */
	if (addr->sa.sa_family != AF_INET6)
		af = sctp_get_af_specific(addr->sa.sa_family);
	else {
		int type = ipv6_addr_type(&addr->v6.sin6_addr);
806 807
		struct net_device *dev;

L
Linus Torvalds 已提交
808
		if (type & IPV6_ADDR_LINKLOCAL) {
809 810 811 812
			if (!addr->v6.sin6_scope_id)
				return 0;
			dev = dev_get_by_index(addr->v6.sin6_scope_id);
			if (!dev)
L
Linus Torvalds 已提交
813
				return 0;
814
			dev_put(dev);
L
Linus Torvalds 已提交
815 816 817 818 819 820
		}
		af = opt->pf->af;
	}
	return af->available(addr, opt);
}

821
/* Verify that the provided sockaddr looks sendable.   Common verification,
L
Linus Torvalds 已提交
822 823 824 825 826 827 828 829 830 831 832
 * has already been taken care of.
 */
static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
{
	struct sctp_af *af = NULL;

	/* ASSERT: address family has already been verified. */
	if (addr->sa.sa_family != AF_INET6)
		af = sctp_get_af_specific(addr->sa.sa_family);
	else {
		int type = ipv6_addr_type(&addr->v6.sin6_addr);
833 834
		struct net_device *dev;

L
Linus Torvalds 已提交
835
		if (type & IPV6_ADDR_LINKLOCAL) {
836 837 838 839
			if (!addr->v6.sin6_scope_id)
				return 0;
			dev = dev_get_by_index(addr->v6.sin6_scope_id);
			if (!dev)
L
Linus Torvalds 已提交
840
				return 0;
841
			dev_put(dev);
L
Linus Torvalds 已提交
842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862
		}
		af = opt->pf->af;
	}

	return af != NULL;
}

/* Fill in Supported Address Type information for INIT and INIT-ACK
 * chunks.   Note: In the future, we may want to look at sock options
 * to determine whether a PF_INET6 socket really wants to have IPV4
 * addresses.
 * Returns number of addresses supported.
 */
static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
				      __u16 *types)
{
	types[0] = SCTP_PARAM_IPV4_ADDRESS;
	types[1] = SCTP_PARAM_IPV6_ADDRESS;
	return 2;
}

863
static const struct proto_ops inet6_seqpacket_ops = {
L
Linus Torvalds 已提交
864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901
	.family     = PF_INET6,
	.owner      = THIS_MODULE,
	.release    = inet6_release,
	.bind       = inet6_bind,
	.connect    = inet_dgram_connect,
	.socketpair = sock_no_socketpair,
	.accept     = inet_accept,
	.getname    = inet6_getname,
	.poll       = sctp_poll,
	.ioctl      = inet6_ioctl,
	.listen     = sctp_inet_listen,
	.shutdown   = inet_shutdown,
	.setsockopt = sock_common_setsockopt,
	.getsockopt = sock_common_getsockopt,
	.sendmsg    = inet_sendmsg,
	.recvmsg    = sock_common_recvmsg,
	.mmap       = sock_no_mmap,
};

static struct inet_protosw sctpv6_seqpacket_protosw = {
	.type          = SOCK_SEQPACKET,
	.protocol      = IPPROTO_SCTP,
	.prot 	       = &sctpv6_prot,
	.ops           = &inet6_seqpacket_ops,
	.capability    = -1,
	.no_check      = 0,
	.flags         = SCTP_PROTOSW_FLAG
};
static struct inet_protosw sctpv6_stream_protosw = {
	.type          = SOCK_STREAM,
	.protocol      = IPPROTO_SCTP,
	.prot 	       = &sctpv6_prot,
	.ops           = &inet6_seqpacket_ops,
	.capability    = -1,
	.no_check      = 0,
	.flags         = SCTP_PROTOSW_FLAG,
};

902
static int sctp6_rcv(struct sk_buff **pskb)
L
Linus Torvalds 已提交
903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995
{
	return sctp_rcv(*pskb) ? -1 : 0;
}

static struct inet6_protocol sctpv6_protocol = {
	.handler      = sctp6_rcv,
	.err_handler  = sctp_v6_err,
	.flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
};

static struct sctp_af sctp_ipv6_specific = {
	.sctp_xmit       = sctp_v6_xmit,
	.setsockopt      = ipv6_setsockopt,
	.getsockopt      = ipv6_getsockopt,
	.get_dst	 = sctp_v6_get_dst,
	.get_saddr	 = sctp_v6_get_saddr,
	.copy_addrlist   = sctp_v6_copy_addrlist,
	.from_skb        = sctp_v6_from_skb,
	.from_sk         = sctp_v6_from_sk,
	.to_sk_saddr     = sctp_v6_to_sk_saddr,
	.to_sk_daddr     = sctp_v6_to_sk_daddr,
	.from_addr_param = sctp_v6_from_addr_param,
	.to_addr_param   = sctp_v6_to_addr_param,
	.dst_saddr       = sctp_v6_dst_saddr,
	.cmp_addr        = sctp_v6_cmp_addr,
	.scope           = sctp_v6_scope,
	.addr_valid      = sctp_v6_addr_valid,
	.inaddr_any      = sctp_v6_inaddr_any,
	.is_any          = sctp_v6_is_any,
	.available       = sctp_v6_available,
	.skb_iif         = sctp_v6_skb_iif,
	.is_ce           = sctp_v6_is_ce,
	.seq_dump_addr   = sctp_v6_seq_dump_addr,
	.net_header_len  = sizeof(struct ipv6hdr),
	.sockaddr_len    = sizeof(struct sockaddr_in6),
	.sa_family       = AF_INET6,
};

static struct sctp_pf sctp_pf_inet6_specific = {
	.event_msgname = sctp_inet6_event_msgname,
	.skb_msgname   = sctp_inet6_skb_msgname,
	.af_supported  = sctp_inet6_af_supported,
	.cmp_addr      = sctp_inet6_cmp_addr,
	.bind_verify   = sctp_inet6_bind_verify,
	.send_verify   = sctp_inet6_send_verify,
	.supported_addrs = sctp_inet6_supported_addrs,
	.create_accept_sk = sctp_v6_create_accept_sk,
	.addr_v4map    = sctp_v6_addr_v4map,
	.af            = &sctp_ipv6_specific,
};

/* Initialize IPv6 support and register with inet6 stack.  */
int sctp_v6_init(void)
{
	int rc = proto_register(&sctpv6_prot, 1);

	if (rc)
		goto out;
	/* Register inet6 protocol. */
	rc = -EAGAIN;
	if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
		goto out_unregister_sctp_proto;

	/* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
	inet6_register_protosw(&sctpv6_seqpacket_protosw);
	inet6_register_protosw(&sctpv6_stream_protosw);

	/* Register the SCTP specific PF_INET6 functions. */
	sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6);

	/* Register the SCTP specific AF_INET6 functions. */
	sctp_register_af(&sctp_ipv6_specific);

	/* Register notifier for inet6 address additions/deletions. */
	register_inet6addr_notifier(&sctp_inet6addr_notifier);
	rc = 0;
out:
	return rc;
out_unregister_sctp_proto:
	proto_unregister(&sctpv6_prot);
	goto out;
}

/* IPv6 specific exit support. */
void sctp_v6_exit(void)
{
	list_del(&sctp_ipv6_specific.list);
	inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
	inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
	inet6_unregister_protosw(&sctpv6_stream_protosw);
	unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
	proto_unregister(&sctpv6_prot);
}