2 * Extension Header handling for IPv6
3 * Linux INET6 implementation
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Andi Kleen <ak@muc.de>
8 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
17 * yoshfuji : ensure not to overrun while parsing
19 * Mitsuru KANDA @USAGI and: Remove ipv6_parse_exthdrs().
20 * YOSHIFUJI Hideaki @USAGI Register inbound extension header
21 * handlers as inet6_protocol{}.
24 #include <linux/errno.h>
25 #include <linux/types.h>
26 #include <linux/socket.h>
27 #include <linux/sockios.h>
28 #include <linux/net.h>
29 #include <linux/netdevice.h>
30 #include <linux/in6.h>
31 #include <linux/icmpv6.h>
32 #include <linux/slab.h>
33 #include <linux/export.h>
40 #include <net/protocol.h>
41 #include <net/transp_v6.h>
42 #include <net/rawv6.h>
43 #include <net/ndisc.h>
44 #include <net/ip6_route.h>
45 #include <net/addrconf.h>
46 #if IS_ENABLED(CONFIG_IPV6_MIP6)
50 #include <asm/uaccess.h>
51 #include "ip6_offload.h"
54 * Parsing tlv encoded headers.
56 * Parsing function "func" returns true, if parsing succeed
57 * and false, if it failed.
58 * It MUST NOT touch skb->h.
63 bool (*func)(struct sk_buff *skb, int offset);
66 /*********************
68 *********************/
70 /* An unknown option is detected, decide what to do */
72 static bool ip6_tlvopt_unknown(struct sk_buff *skb, int optoff)
74 switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) {
78 case 1: /* drop packet */
81 case 3: /* Send ICMP if not a multicast address and drop packet */
82 /* Actually, it is redundant check. icmp_send
83 will recheck in any case.
85 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr))
87 case 2: /* send ICMP PARM PROB regardless and drop packet */
88 icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff);
96 /* Parse tlv encoded option header (hop-by-hop or destination) */
98 static bool ip6_parse_tlv(const struct tlvtype_proc *procs, struct sk_buff *skb)
100 const struct tlvtype_proc *curr;
101 const unsigned char *nh = skb_network_header(skb);
102 int off = skb_network_header_len(skb);
103 int len = (skb_transport_header(skb)[1] + 1) << 3;
106 if (skb_transport_offset(skb) + len > skb_headlen(skb))
113 int optlen = nh[off + 1] + 2;
125 /* RFC 2460 states that the purpose of PadN is
126 * to align the containing header to multiples
127 * of 8. 7 is therefore the highest valid value.
128 * See also RFC 4942, Section 2.1.9.5.
133 /* RFC 4942 recommends receiving hosts to
134 * actively check PadN payload to contain
137 for (i = 2; i < optlen; i++) {
138 if (nh[off + i] != 0)
143 default: /* Other TLV code so scan list */
146 for (curr=procs; curr->type >= 0; curr++) {
147 if (curr->type == nh[off]) {
148 /* type specific length/alignment
149 checks will be performed in the
151 if (curr->func(skb, off) == false)
156 if (curr->type < 0) {
157 if (ip6_tlvopt_unknown(skb, off) == 0)
166 /* This case will not be caught by above check since its padding
167 * length is smaller than 7:
168 * 1 byte NH + 1 byte Length + 6 bytes Padding
170 if ((padlen == 6) && ((off - skb_network_header_len(skb)) == 8))
180 /*****************************
181 Destination options header.
182 *****************************/
184 #if IS_ENABLED(CONFIG_IPV6_MIP6)
185 static bool ipv6_dest_hao(struct sk_buff *skb, int optoff)
187 struct ipv6_destopt_hao *hao;
188 struct inet6_skb_parm *opt = IP6CB(skb);
189 struct ipv6hdr *ipv6h = ipv6_hdr(skb);
190 struct in6_addr tmp_addr;
194 LIMIT_NETDEBUG(KERN_DEBUG "hao duplicated\n");
197 opt->dsthao = opt->dst1;
200 hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff);
202 if (hao->length != 16) {
204 KERN_DEBUG "hao invalid option length = %d\n", hao->length);
208 if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) {
210 KERN_DEBUG "hao is not an unicast addr: %pI6\n", &hao->addr);
214 ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr,
215 (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS);
216 if (unlikely(ret < 0))
219 if (skb_cloned(skb)) {
220 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
223 /* update all variable using below by copied skbuff */
224 hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) +
226 ipv6h = ipv6_hdr(skb);
229 if (skb->ip_summed == CHECKSUM_COMPLETE)
230 skb->ip_summed = CHECKSUM_NONE;
232 tmp_addr = ipv6h->saddr;
233 ipv6h->saddr = hao->addr;
234 hao->addr = tmp_addr;
236 if (skb->tstamp.tv64 == 0)
237 __net_timestamp(skb);
247 static const struct tlvtype_proc tlvprocdestopt_lst[] = {
248 #if IS_ENABLED(CONFIG_IPV6_MIP6)
250 .type = IPV6_TLV_HAO,
251 .func = ipv6_dest_hao,
257 static int ipv6_destopt_rcv(struct sk_buff *skb)
259 struct inet6_skb_parm *opt = IP6CB(skb);
260 #if IS_ENABLED(CONFIG_IPV6_MIP6)
263 struct dst_entry *dst = skb_dst(skb);
265 if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
266 !pskb_may_pull(skb, (skb_transport_offset(skb) +
267 ((skb_transport_header(skb)[1] + 1) << 3)))) {
268 IP6_INC_STATS_BH(dev_net(dst->dev), ip6_dst_idev(dst),
269 IPSTATS_MIB_INHDRERRORS);
274 opt->lastopt = opt->dst1 = skb_network_header_len(skb);
275 #if IS_ENABLED(CONFIG_IPV6_MIP6)
279 if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) {
280 skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
282 #if IS_ENABLED(CONFIG_IPV6_MIP6)
285 opt->nhoff = opt->dst1;
290 IP6_INC_STATS_BH(dev_net(dst->dev),
291 ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS);
295 /********************************
297 ********************************/
299 /* called with rcu_read_lock() */
300 static int ipv6_rthdr_rcv(struct sk_buff *skb)
302 struct inet6_skb_parm *opt = IP6CB(skb);
303 struct in6_addr *addr = NULL;
304 struct in6_addr daddr;
305 struct inet6_dev *idev;
307 struct ipv6_rt_hdr *hdr;
308 struct rt0_hdr *rthdr;
309 struct net *net = dev_net(skb->dev);
310 int accept_source_route = net->ipv6.devconf_all->accept_source_route;
312 idev = __in6_dev_get(skb->dev);
313 if (idev && accept_source_route > idev->cnf.accept_source_route)
314 accept_source_route = idev->cnf.accept_source_route;
316 if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
317 !pskb_may_pull(skb, (skb_transport_offset(skb) +
318 ((skb_transport_header(skb)[1] + 1) << 3)))) {
319 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
320 IPSTATS_MIB_INHDRERRORS);
325 hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
327 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) ||
328 skb->pkt_type != PACKET_HOST) {
329 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
330 IPSTATS_MIB_INADDRERRORS);
336 if (hdr->segments_left == 0) {
338 #if IS_ENABLED(CONFIG_IPV6_MIP6)
339 case IPV6_SRCRT_TYPE_2:
340 /* Silently discard type 2 header unless it was
344 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
345 IPSTATS_MIB_INADDRERRORS);
355 opt->lastopt = opt->srcrt = skb_network_header_len(skb);
356 skb->transport_header += (hdr->hdrlen + 1) << 3;
357 opt->dst0 = opt->dst1;
359 opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
364 #if IS_ENABLED(CONFIG_IPV6_MIP6)
365 case IPV6_SRCRT_TYPE_2:
366 if (accept_source_route < 0)
368 /* Silently discard invalid RTH type 2 */
369 if (hdr->hdrlen != 2 || hdr->segments_left != 1) {
370 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
371 IPSTATS_MIB_INHDRERRORS);
382 * This is the routing header forwarding algorithm from
386 n = hdr->hdrlen >> 1;
388 if (hdr->segments_left > n) {
389 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
390 IPSTATS_MIB_INHDRERRORS);
391 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
392 ((&hdr->segments_left) -
393 skb_network_header(skb)));
397 /* We are about to mangle packet header. Be careful!
398 Do not damage packets queued somewhere.
400 if (skb_cloned(skb)) {
401 /* the copy is a forwarded packet */
402 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
403 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
404 IPSTATS_MIB_OUTDISCARDS);
408 hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
411 if (skb->ip_summed == CHECKSUM_COMPLETE)
412 skb->ip_summed = CHECKSUM_NONE;
414 i = n - --hdr->segments_left;
416 rthdr = (struct rt0_hdr *) hdr;
421 #if IS_ENABLED(CONFIG_IPV6_MIP6)
422 case IPV6_SRCRT_TYPE_2:
423 if (xfrm6_input_addr(skb, (xfrm_address_t *)addr,
424 (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
425 IPPROTO_ROUTING) < 0) {
426 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
427 IPSTATS_MIB_INADDRERRORS);
431 if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) {
432 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
433 IPSTATS_MIB_INADDRERRORS);
443 if (ipv6_addr_is_multicast(addr)) {
444 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
445 IPSTATS_MIB_INADDRERRORS);
451 *addr = ipv6_hdr(skb)->daddr;
452 ipv6_hdr(skb)->daddr = daddr;
455 ip6_route_input(skb);
456 if (skb_dst(skb)->error) {
457 skb_push(skb, skb->data - skb_network_header(skb));
462 if (skb_dst(skb)->dev->flags&IFF_LOOPBACK) {
463 if (ipv6_hdr(skb)->hop_limit <= 1) {
464 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
465 IPSTATS_MIB_INHDRERRORS);
466 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
471 ipv6_hdr(skb)->hop_limit--;
475 skb_push(skb, skb->data - skb_network_header(skb));
480 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS);
481 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
482 (&hdr->type) - skb_network_header(skb));
486 static const struct inet6_protocol rthdr_protocol = {
487 .handler = ipv6_rthdr_rcv,
488 .flags = INET6_PROTO_NOPOLICY,
491 static const struct inet6_protocol destopt_protocol = {
492 .handler = ipv6_destopt_rcv,
493 .flags = INET6_PROTO_NOPOLICY,
496 static const struct inet6_protocol nodata_protocol = {
497 .handler = dst_discard,
498 .flags = INET6_PROTO_NOPOLICY,
501 int __init ipv6_exthdrs_init(void)
505 ret = ipv6_exthdrs_offload_init();
509 ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING);
513 ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
517 ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE);
524 inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
526 inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING);
528 ipv6_exthdrs_offload_exit();
532 void ipv6_exthdrs_exit(void)
534 ipv6_exthdrs_offload_exit();
535 inet6_del_protocol(&nodata_protocol, IPPROTO_NONE);
536 inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
537 inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING);
540 /**********************************
542 **********************************/
545 * Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input().
547 static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb)
549 return skb_dst(skb) ? ip6_dst_idev(skb_dst(skb)) : __in6_dev_get(skb->dev);
552 static inline struct net *ipv6_skb_net(struct sk_buff *skb)
554 return skb_dst(skb) ? dev_net(skb_dst(skb)->dev) : dev_net(skb->dev);
557 /* Router Alert as of RFC 2711 */
559 static bool ipv6_hop_ra(struct sk_buff *skb, int optoff)
561 const unsigned char *nh = skb_network_header(skb);
563 if (nh[optoff + 1] == 2) {
564 IP6CB(skb)->ra = optoff;
567 LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n",
575 static bool ipv6_hop_jumbo(struct sk_buff *skb, int optoff)
577 const unsigned char *nh = skb_network_header(skb);
578 struct net *net = ipv6_skb_net(skb);
581 if (nh[optoff + 1] != 4 || (optoff & 3) != 2) {
582 LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n",
584 IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
585 IPSTATS_MIB_INHDRERRORS);
589 pkt_len = ntohl(*(__be32 *)(nh + optoff + 2));
590 if (pkt_len <= IPV6_MAXPLEN) {
591 IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
592 IPSTATS_MIB_INHDRERRORS);
593 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2);
596 if (ipv6_hdr(skb)->payload_len) {
597 IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
598 IPSTATS_MIB_INHDRERRORS);
599 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff);
603 if (pkt_len > skb->len - sizeof(struct ipv6hdr)) {
604 IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
605 IPSTATS_MIB_INTRUNCATEDPKTS);
609 if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr)))
619 static const struct tlvtype_proc tlvprochopopt_lst[] = {
621 .type = IPV6_TLV_ROUTERALERT,
625 .type = IPV6_TLV_JUMBO,
626 .func = ipv6_hop_jumbo,
631 int ipv6_parse_hopopts(struct sk_buff *skb)
633 struct inet6_skb_parm *opt = IP6CB(skb);
636 * skb_network_header(skb) is equal to skb->data, and
637 * skb_network_header_len(skb) is always equal to
638 * sizeof(struct ipv6hdr) by definition of
639 * hop-by-hop options.
641 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) ||
642 !pskb_may_pull(skb, (sizeof(struct ipv6hdr) +
643 ((skb_transport_header(skb)[1] + 1) << 3)))) {
648 opt->hop = sizeof(struct ipv6hdr);
649 if (ip6_parse_tlv(tlvprochopopt_lst, skb)) {
650 skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
652 opt->nhoff = sizeof(struct ipv6hdr);
659 * Creating outbound headers.
661 * "build" functions work when skb is filled from head to tail (datagram)
662 * "push" functions work when headers are added from tail to head (tcp)
664 * In both cases we assume, that caller reserved enough room
668 static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto,
669 struct ipv6_rt_hdr *opt,
670 struct in6_addr **addr_p)
672 struct rt0_hdr *phdr, *ihdr;
675 ihdr = (struct rt0_hdr *) opt;
677 phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3);
678 memcpy(phdr, ihdr, sizeof(struct rt0_hdr));
680 hops = ihdr->rt_hdr.hdrlen >> 1;
683 memcpy(phdr->addr, ihdr->addr + 1,
684 (hops - 1) * sizeof(struct in6_addr));
686 phdr->addr[hops - 1] = **addr_p;
687 *addr_p = ihdr->addr;
689 phdr->rt_hdr.nexthdr = *proto;
690 *proto = NEXTHDR_ROUTING;
693 static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt)
695 struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt));
697 memcpy(h, opt, ipv6_optlen(opt));
702 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
704 struct in6_addr **daddr)
707 ipv6_push_rthdr(skb, proto, opt->srcrt, daddr);
709 * IPV6_RTHDRDSTOPTS is ignored
710 * unless IPV6_RTHDR is set (RFC3542).
713 ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt);
716 ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt);
718 EXPORT_SYMBOL(ipv6_push_nfrag_opts);
720 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto)
723 ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt);
726 struct ipv6_txoptions *
727 ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt)
729 struct ipv6_txoptions *opt2;
731 opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC);
733 long dif = (char *)opt2 - (char *)opt;
734 memcpy(opt2, opt, opt->tot_len);
736 *((char **)&opt2->hopopt) += dif;
738 *((char **)&opt2->dst0opt) += dif;
740 *((char **)&opt2->dst1opt) += dif;
742 *((char **)&opt2->srcrt) += dif;
746 EXPORT_SYMBOL_GPL(ipv6_dup_options);
748 static int ipv6_renew_option(void *ohdr,
749 struct ipv6_opt_hdr __user *newopt, int newoptlen,
751 struct ipv6_opt_hdr **hdr,
756 memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr));
757 *hdr = (struct ipv6_opt_hdr *)*p;
758 *p += CMSG_ALIGN(ipv6_optlen(*hdr));
762 if (copy_from_user(*p, newopt, newoptlen))
764 *hdr = (struct ipv6_opt_hdr *)*p;
765 if (ipv6_optlen(*hdr) > newoptlen)
767 *p += CMSG_ALIGN(newoptlen);
773 struct ipv6_txoptions *
774 ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt,
776 struct ipv6_opt_hdr __user *newopt, int newoptlen)
780 struct ipv6_txoptions *opt2;
784 if (newtype != IPV6_HOPOPTS && opt->hopopt)
785 tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt));
786 if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt)
787 tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt));
788 if (newtype != IPV6_RTHDR && opt->srcrt)
789 tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt));
790 if (newtype != IPV6_DSTOPTS && opt->dst1opt)
791 tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt));
794 if (newopt && newoptlen)
795 tot_len += CMSG_ALIGN(newoptlen);
800 tot_len += sizeof(*opt2);
801 opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC);
803 return ERR_PTR(-ENOBUFS);
805 memset(opt2, 0, tot_len);
807 opt2->tot_len = tot_len;
808 p = (char *)(opt2 + 1);
810 err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen,
811 newtype != IPV6_HOPOPTS,
816 err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen,
817 newtype != IPV6_RTHDRDSTOPTS,
822 err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen,
823 newtype != IPV6_RTHDR,
824 (struct ipv6_opt_hdr **)&opt2->srcrt, &p);
828 err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen,
829 newtype != IPV6_DSTOPTS,
834 opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) +
835 (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) +
836 (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0);
837 opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0);
841 sock_kfree_s(sk, opt2, opt2->tot_len);
845 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
846 struct ipv6_txoptions *opt)
849 * ignore the dest before srcrt unless srcrt is being included.
852 if (opt && opt->dst0opt && !opt->srcrt) {
853 if (opt_space != opt) {
854 memcpy(opt_space, opt, sizeof(*opt_space));
857 opt->opt_nflen -= ipv6_optlen(opt->dst0opt);
863 EXPORT_SYMBOL_GPL(ipv6_fixup_options);
866 * fl6_update_dst - update flowi destination address with info given
867 * by srcrt option, if any.
869 * @fl6: flowi6 for which daddr is to be updated
870 * @opt: struct ipv6_txoptions in which to look for srcrt opt
871 * @orig: copy of original daddr address if modified
873 * Returns NULL if no txoptions or no srcrt, otherwise returns orig
874 * and initial value of fl6->daddr set in orig
876 struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
877 const struct ipv6_txoptions *opt,
878 struct in6_addr *orig)
880 if (!opt || !opt->srcrt)
884 fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr;
887 EXPORT_SYMBOL_GPL(fl6_update_dst);