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![Alexander Aring](/assets/img/avatar_default.png)
This patch adds rpl source routing receive handling. Everything works only if sysconf "rpl_seg_enabled" and source routing is enabled. Mostly the same behaviour as IPv6 segmentation routing. To handle compression and uncompression a rpl.c file is created which contains the necessary functionality. The receive handling will also care about IPv6 encapsulated so far it's specified as possible nexthdr in RFC 6554. Signed-off-by: Alexander Aring <alex.aring@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1365 lines
32 KiB
C
1365 lines
32 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Extension Header handling for IPv6
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* Linux INET6 implementation
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*
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* Authors:
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* Pedro Roque <roque@di.fc.ul.pt>
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* Andi Kleen <ak@muc.de>
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* Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
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*/
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/* Changes:
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* yoshfuji : ensure not to overrun while parsing
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* tlv options.
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* Mitsuru KANDA @USAGI and: Remove ipv6_parse_exthdrs().
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* YOSHIFUJI Hideaki @USAGI Register inbound extension header
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* handlers as inet6_protocol{}.
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*/
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#include <linux/errno.h>
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#include <linux/types.h>
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#include <linux/socket.h>
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#include <linux/sockios.h>
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#include <linux/net.h>
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#include <linux/netdevice.h>
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#include <linux/in6.h>
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#include <linux/icmpv6.h>
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#include <linux/slab.h>
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#include <linux/export.h>
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#include <net/dst.h>
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#include <net/sock.h>
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#include <net/snmp.h>
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#include <net/ipv6.h>
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#include <net/protocol.h>
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#include <net/transp_v6.h>
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#include <net/rawv6.h>
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#include <net/ndisc.h>
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#include <net/ip6_route.h>
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#include <net/addrconf.h>
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#include <net/calipso.h>
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#if IS_ENABLED(CONFIG_IPV6_MIP6)
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#include <net/xfrm.h>
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#endif
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#include <linux/seg6.h>
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#include <net/seg6.h>
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#ifdef CONFIG_IPV6_SEG6_HMAC
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#include <net/seg6_hmac.h>
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#endif
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#include <net/rpl.h>
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#include <linux/uaccess.h>
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/*
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* Parsing tlv encoded headers.
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*
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* Parsing function "func" returns true, if parsing succeed
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* and false, if it failed.
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* It MUST NOT touch skb->h.
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*/
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struct tlvtype_proc {
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int type;
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bool (*func)(struct sk_buff *skb, int offset);
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};
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/*********************
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Generic functions
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*********************/
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/* An unknown option is detected, decide what to do */
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static bool ip6_tlvopt_unknown(struct sk_buff *skb, int optoff,
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bool disallow_unknowns)
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{
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if (disallow_unknowns) {
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/* If unknown TLVs are disallowed by configuration
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* then always silently drop packet. Note this also
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* means no ICMP parameter problem is sent which
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* could be a good property to mitigate a reflection DOS
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* attack.
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*/
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goto drop;
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}
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switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) {
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case 0: /* ignore */
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return true;
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case 1: /* drop packet */
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break;
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case 3: /* Send ICMP if not a multicast address and drop packet */
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/* Actually, it is redundant check. icmp_send
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will recheck in any case.
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*/
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if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr))
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break;
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fallthrough;
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case 2: /* send ICMP PARM PROB regardless and drop packet */
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icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff);
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return false;
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}
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drop:
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kfree_skb(skb);
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return false;
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}
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/* Parse tlv encoded option header (hop-by-hop or destination) */
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static bool ip6_parse_tlv(const struct tlvtype_proc *procs,
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struct sk_buff *skb,
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int max_count)
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{
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int len = (skb_transport_header(skb)[1] + 1) << 3;
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const unsigned char *nh = skb_network_header(skb);
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int off = skb_network_header_len(skb);
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const struct tlvtype_proc *curr;
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bool disallow_unknowns = false;
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int tlv_count = 0;
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int padlen = 0;
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if (unlikely(max_count < 0)) {
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disallow_unknowns = true;
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max_count = -max_count;
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}
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if (skb_transport_offset(skb) + len > skb_headlen(skb))
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goto bad;
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off += 2;
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len -= 2;
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while (len > 0) {
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int optlen = nh[off + 1] + 2;
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int i;
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switch (nh[off]) {
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case IPV6_TLV_PAD1:
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optlen = 1;
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padlen++;
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if (padlen > 7)
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goto bad;
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break;
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case IPV6_TLV_PADN:
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/* RFC 2460 states that the purpose of PadN is
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* to align the containing header to multiples
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* of 8. 7 is therefore the highest valid value.
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* See also RFC 4942, Section 2.1.9.5.
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*/
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padlen += optlen;
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if (padlen > 7)
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goto bad;
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/* RFC 4942 recommends receiving hosts to
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* actively check PadN payload to contain
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* only zeroes.
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*/
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for (i = 2; i < optlen; i++) {
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if (nh[off + i] != 0)
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goto bad;
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}
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break;
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default: /* Other TLV code so scan list */
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if (optlen > len)
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goto bad;
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tlv_count++;
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if (tlv_count > max_count)
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goto bad;
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for (curr = procs; curr->type >= 0; curr++) {
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if (curr->type == nh[off]) {
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/* type specific length/alignment
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checks will be performed in the
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func(). */
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if (curr->func(skb, off) == false)
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return false;
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break;
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}
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}
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if (curr->type < 0 &&
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!ip6_tlvopt_unknown(skb, off, disallow_unknowns))
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return false;
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padlen = 0;
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break;
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}
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off += optlen;
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len -= optlen;
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}
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if (len == 0)
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return true;
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bad:
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kfree_skb(skb);
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return false;
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}
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/*****************************
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Destination options header.
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*****************************/
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#if IS_ENABLED(CONFIG_IPV6_MIP6)
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static bool ipv6_dest_hao(struct sk_buff *skb, int optoff)
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{
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struct ipv6_destopt_hao *hao;
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struct inet6_skb_parm *opt = IP6CB(skb);
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struct ipv6hdr *ipv6h = ipv6_hdr(skb);
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int ret;
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if (opt->dsthao) {
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net_dbg_ratelimited("hao duplicated\n");
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goto discard;
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}
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opt->dsthao = opt->dst1;
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opt->dst1 = 0;
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hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff);
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if (hao->length != 16) {
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net_dbg_ratelimited("hao invalid option length = %d\n",
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hao->length);
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goto discard;
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}
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if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) {
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net_dbg_ratelimited("hao is not an unicast addr: %pI6\n",
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&hao->addr);
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goto discard;
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}
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ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr,
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(xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS);
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if (unlikely(ret < 0))
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goto discard;
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if (skb_cloned(skb)) {
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if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
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goto discard;
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/* update all variable using below by copied skbuff */
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hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) +
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optoff);
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ipv6h = ipv6_hdr(skb);
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}
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if (skb->ip_summed == CHECKSUM_COMPLETE)
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skb->ip_summed = CHECKSUM_NONE;
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swap(ipv6h->saddr, hao->addr);
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if (skb->tstamp == 0)
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__net_timestamp(skb);
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return true;
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discard:
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kfree_skb(skb);
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return false;
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}
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#endif
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static const struct tlvtype_proc tlvprocdestopt_lst[] = {
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#if IS_ENABLED(CONFIG_IPV6_MIP6)
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{
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.type = IPV6_TLV_HAO,
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.func = ipv6_dest_hao,
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},
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#endif
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{-1, NULL}
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};
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static int ipv6_destopt_rcv(struct sk_buff *skb)
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{
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struct inet6_dev *idev = __in6_dev_get(skb->dev);
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struct inet6_skb_parm *opt = IP6CB(skb);
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#if IS_ENABLED(CONFIG_IPV6_MIP6)
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__u16 dstbuf;
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#endif
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struct dst_entry *dst = skb_dst(skb);
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struct net *net = dev_net(skb->dev);
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int extlen;
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if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
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!pskb_may_pull(skb, (skb_transport_offset(skb) +
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((skb_transport_header(skb)[1] + 1) << 3)))) {
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__IP6_INC_STATS(dev_net(dst->dev), idev,
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IPSTATS_MIB_INHDRERRORS);
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fail_and_free:
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kfree_skb(skb);
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return -1;
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}
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extlen = (skb_transport_header(skb)[1] + 1) << 3;
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if (extlen > net->ipv6.sysctl.max_dst_opts_len)
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goto fail_and_free;
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opt->lastopt = opt->dst1 = skb_network_header_len(skb);
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#if IS_ENABLED(CONFIG_IPV6_MIP6)
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dstbuf = opt->dst1;
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#endif
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if (ip6_parse_tlv(tlvprocdestopt_lst, skb,
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init_net.ipv6.sysctl.max_dst_opts_cnt)) {
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skb->transport_header += extlen;
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opt = IP6CB(skb);
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#if IS_ENABLED(CONFIG_IPV6_MIP6)
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opt->nhoff = dstbuf;
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#else
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opt->nhoff = opt->dst1;
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#endif
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return 1;
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}
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__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
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return -1;
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}
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static void seg6_update_csum(struct sk_buff *skb)
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{
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struct ipv6_sr_hdr *hdr;
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struct in6_addr *addr;
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__be32 from, to;
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/* srh is at transport offset and seg_left is already decremented
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* but daddr is not yet updated with next segment
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*/
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hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb);
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addr = hdr->segments + hdr->segments_left;
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hdr->segments_left++;
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from = *(__be32 *)hdr;
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hdr->segments_left--;
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to = *(__be32 *)hdr;
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/* update skb csum with diff resulting from seg_left decrement */
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update_csum_diff4(skb, from, to);
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/* compute csum diff between current and next segment and update */
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update_csum_diff16(skb, (__be32 *)(&ipv6_hdr(skb)->daddr),
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(__be32 *)addr);
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}
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static int ipv6_srh_rcv(struct sk_buff *skb)
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{
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struct inet6_skb_parm *opt = IP6CB(skb);
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struct net *net = dev_net(skb->dev);
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struct ipv6_sr_hdr *hdr;
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struct inet6_dev *idev;
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struct in6_addr *addr;
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int accept_seg6;
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hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb);
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idev = __in6_dev_get(skb->dev);
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accept_seg6 = net->ipv6.devconf_all->seg6_enabled;
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if (accept_seg6 > idev->cnf.seg6_enabled)
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accept_seg6 = idev->cnf.seg6_enabled;
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if (!accept_seg6) {
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kfree_skb(skb);
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return -1;
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}
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#ifdef CONFIG_IPV6_SEG6_HMAC
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if (!seg6_hmac_validate_skb(skb)) {
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kfree_skb(skb);
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return -1;
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}
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#endif
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looped_back:
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if (hdr->segments_left == 0) {
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if (hdr->nexthdr == NEXTHDR_IPV6) {
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int offset = (hdr->hdrlen + 1) << 3;
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skb_postpull_rcsum(skb, skb_network_header(skb),
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skb_network_header_len(skb));
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if (!pskb_pull(skb, offset)) {
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kfree_skb(skb);
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return -1;
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}
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skb_postpull_rcsum(skb, skb_transport_header(skb),
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offset);
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|
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skb_reset_network_header(skb);
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skb_reset_transport_header(skb);
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skb->encapsulation = 0;
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__skb_tunnel_rx(skb, skb->dev, net);
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netif_rx(skb);
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return -1;
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}
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opt->srcrt = skb_network_header_len(skb);
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opt->lastopt = opt->srcrt;
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skb->transport_header += (hdr->hdrlen + 1) << 3;
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opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
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return 1;
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}
|
|
|
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if (hdr->segments_left >= (hdr->hdrlen >> 1)) {
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__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
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icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
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((&hdr->segments_left) -
|
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skb_network_header(skb)));
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return -1;
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}
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|
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if (skb_cloned(skb)) {
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if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
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__IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
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IPSTATS_MIB_OUTDISCARDS);
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kfree_skb(skb);
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return -1;
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}
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}
|
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hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb);
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|
|
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hdr->segments_left--;
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addr = hdr->segments + hdr->segments_left;
|
|
|
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skb_push(skb, sizeof(struct ipv6hdr));
|
|
|
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if (skb->ip_summed == CHECKSUM_COMPLETE)
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seg6_update_csum(skb);
|
|
|
|
ipv6_hdr(skb)->daddr = *addr;
|
|
|
|
skb_dst_drop(skb);
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|
|
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ip6_route_input(skb);
|
|
|
|
if (skb_dst(skb)->error) {
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dst_input(skb);
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return -1;
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|
}
|
|
|
|
if (skb_dst(skb)->dev->flags & IFF_LOOPBACK) {
|
|
if (ipv6_hdr(skb)->hop_limit <= 1) {
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__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
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icmpv6_send(skb, ICMPV6_TIME_EXCEED,
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ICMPV6_EXC_HOPLIMIT, 0);
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kfree_skb(skb);
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return -1;
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}
|
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ipv6_hdr(skb)->hop_limit--;
|
|
|
|
skb_pull(skb, sizeof(struct ipv6hdr));
|
|
goto looped_back;
|
|
}
|
|
|
|
dst_input(skb);
|
|
|
|
return -1;
|
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}
|
|
|
|
static int ipv6_rpl_srh_rcv(struct sk_buff *skb)
|
|
{
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|
struct ipv6_rpl_sr_hdr *hdr, *ohdr, *chdr;
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|
struct inet6_skb_parm *opt = IP6CB(skb);
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|
struct net *net = dev_net(skb->dev);
|
|
struct inet6_dev *idev;
|
|
struct ipv6hdr *oldhdr;
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struct in6_addr addr;
|
|
unsigned char *buf;
|
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int accept_rpl_seg;
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|
int i, err;
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|
u64 n = 0;
|
|
u32 r;
|
|
|
|
idev = __in6_dev_get(skb->dev);
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|
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|
accept_rpl_seg = net->ipv6.devconf_all->rpl_seg_enabled;
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|
if (accept_rpl_seg > idev->cnf.rpl_seg_enabled)
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|
accept_rpl_seg = idev->cnf.rpl_seg_enabled;
|
|
|
|
if (!accept_rpl_seg) {
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kfree_skb(skb);
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return -1;
|
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}
|
|
|
|
looped_back:
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|
hdr = (struct ipv6_rpl_sr_hdr *)skb_transport_header(skb);
|
|
|
|
if (hdr->segments_left == 0) {
|
|
if (hdr->nexthdr == NEXTHDR_IPV6) {
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|
int offset = (hdr->hdrlen + 1) << 3;
|
|
|
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skb_postpull_rcsum(skb, skb_network_header(skb),
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|
skb_network_header_len(skb));
|
|
|
|
if (!pskb_pull(skb, offset)) {
|
|
kfree_skb(skb);
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|
return -1;
|
|
}
|
|
skb_postpull_rcsum(skb, skb_transport_header(skb),
|
|
offset);
|
|
|
|
skb_reset_network_header(skb);
|
|
skb_reset_transport_header(skb);
|
|
skb->encapsulation = 0;
|
|
|
|
__skb_tunnel_rx(skb, skb->dev, net);
|
|
|
|
netif_rx(skb);
|
|
return -1;
|
|
}
|
|
|
|
opt->srcrt = skb_network_header_len(skb);
|
|
opt->lastopt = opt->srcrt;
|
|
skb->transport_header += (hdr->hdrlen + 1) << 3;
|
|
opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
|
|
|
|
return 1;
|
|
}
|
|
|
|
if (!pskb_may_pull(skb, sizeof(*hdr))) {
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
|
|
n = (hdr->hdrlen << 3) - hdr->pad - (16 - hdr->cmpre);
|
|
r = do_div(n, (16 - hdr->cmpri));
|
|
/* checks if calculation was without remainder and n fits into
|
|
* unsigned char which is segments_left field. Should not be
|
|
* higher than that.
|
|
*/
|
|
if (r || (n + 1) > 255) {
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
|
|
if (hdr->segments_left > n + 1) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
|
icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
|
|
((&hdr->segments_left) -
|
|
skb_network_header(skb)));
|
|
return -1;
|
|
}
|
|
|
|
if (skb_cloned(skb)) {
|
|
if (pskb_expand_head(skb, IPV6_RPL_SRH_WORST_SWAP_SIZE, 0,
|
|
GFP_ATOMIC)) {
|
|
__IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
|
|
IPSTATS_MIB_OUTDISCARDS);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
} else {
|
|
err = skb_cow_head(skb, IPV6_RPL_SRH_WORST_SWAP_SIZE);
|
|
if (unlikely(err)) {
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
hdr = (struct ipv6_rpl_sr_hdr *)skb_transport_header(skb);
|
|
|
|
if (!pskb_may_pull(skb, ipv6_rpl_srh_size(n, hdr->cmpri,
|
|
hdr->cmpre))) {
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
|
|
hdr->segments_left--;
|
|
i = n - hdr->segments_left;
|
|
|
|
buf = kzalloc(ipv6_rpl_srh_alloc_size(n + 1) * 2, GFP_ATOMIC);
|
|
if (unlikely(!buf)) {
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
|
|
ohdr = (struct ipv6_rpl_sr_hdr *)buf;
|
|
ipv6_rpl_srh_decompress(ohdr, hdr, &ipv6_hdr(skb)->daddr, n);
|
|
chdr = (struct ipv6_rpl_sr_hdr *)(buf + ((ohdr->hdrlen + 1) << 3));
|
|
|
|
if ((ipv6_addr_type(&ipv6_hdr(skb)->daddr) & IPV6_ADDR_MULTICAST) ||
|
|
(ipv6_addr_type(&ohdr->rpl_segaddr[i]) & IPV6_ADDR_MULTICAST)) {
|
|
kfree_skb(skb);
|
|
kfree(buf);
|
|
return -1;
|
|
}
|
|
|
|
err = ipv6_chk_rpl_srh_loop(net, ohdr->rpl_segaddr, n + 1);
|
|
if (err) {
|
|
icmpv6_send(skb, ICMPV6_PARAMPROB, 0, 0);
|
|
kfree_skb(skb);
|
|
kfree(buf);
|
|
return -1;
|
|
}
|
|
|
|
addr = ipv6_hdr(skb)->daddr;
|
|
ipv6_hdr(skb)->daddr = ohdr->rpl_segaddr[i];
|
|
ohdr->rpl_segaddr[i] = addr;
|
|
|
|
ipv6_rpl_srh_compress(chdr, ohdr, &ipv6_hdr(skb)->daddr, n);
|
|
|
|
oldhdr = ipv6_hdr(skb);
|
|
|
|
skb_pull(skb, ((hdr->hdrlen + 1) << 3));
|
|
skb_postpull_rcsum(skb, oldhdr,
|
|
sizeof(struct ipv6hdr) + ((hdr->hdrlen + 1) << 3));
|
|
skb_push(skb, ((chdr->hdrlen + 1) << 3) + sizeof(struct ipv6hdr));
|
|
skb_reset_network_header(skb);
|
|
skb_mac_header_rebuild(skb);
|
|
skb_set_transport_header(skb, sizeof(struct ipv6hdr));
|
|
|
|
memmove(ipv6_hdr(skb), oldhdr, sizeof(struct ipv6hdr));
|
|
memcpy(skb_transport_header(skb), chdr, (chdr->hdrlen + 1) << 3);
|
|
|
|
ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
|
|
skb_postpush_rcsum(skb, ipv6_hdr(skb),
|
|
sizeof(struct ipv6hdr) + ((chdr->hdrlen + 1) << 3));
|
|
|
|
kfree(buf);
|
|
|
|
skb_dst_drop(skb);
|
|
|
|
ip6_route_input(skb);
|
|
|
|
if (skb_dst(skb)->error) {
|
|
dst_input(skb);
|
|
return -1;
|
|
}
|
|
|
|
if (skb_dst(skb)->dev->flags & IFF_LOOPBACK) {
|
|
if (ipv6_hdr(skb)->hop_limit <= 1) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
|
icmpv6_send(skb, ICMPV6_TIME_EXCEED,
|
|
ICMPV6_EXC_HOPLIMIT, 0);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
ipv6_hdr(skb)->hop_limit--;
|
|
|
|
skb_pull(skb, sizeof(struct ipv6hdr));
|
|
goto looped_back;
|
|
}
|
|
|
|
dst_input(skb);
|
|
|
|
return -1;
|
|
}
|
|
|
|
/********************************
|
|
Routing header.
|
|
********************************/
|
|
|
|
/* called with rcu_read_lock() */
|
|
static int ipv6_rthdr_rcv(struct sk_buff *skb)
|
|
{
|
|
struct inet6_dev *idev = __in6_dev_get(skb->dev);
|
|
struct inet6_skb_parm *opt = IP6CB(skb);
|
|
struct in6_addr *addr = NULL;
|
|
struct in6_addr daddr;
|
|
int n, i;
|
|
struct ipv6_rt_hdr *hdr;
|
|
struct rt0_hdr *rthdr;
|
|
struct net *net = dev_net(skb->dev);
|
|
int accept_source_route = net->ipv6.devconf_all->accept_source_route;
|
|
|
|
idev = __in6_dev_get(skb->dev);
|
|
if (idev && accept_source_route > idev->cnf.accept_source_route)
|
|
accept_source_route = idev->cnf.accept_source_route;
|
|
|
|
if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
|
|
!pskb_may_pull(skb, (skb_transport_offset(skb) +
|
|
((skb_transport_header(skb)[1] + 1) << 3)))) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
|
|
hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
|
|
|
|
if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) ||
|
|
skb->pkt_type != PACKET_HOST) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
|
|
switch (hdr->type) {
|
|
case IPV6_SRCRT_TYPE_4:
|
|
/* segment routing */
|
|
return ipv6_srh_rcv(skb);
|
|
case IPV6_SRCRT_TYPE_3:
|
|
/* rpl segment routing */
|
|
return ipv6_rpl_srh_rcv(skb);
|
|
default:
|
|
break;
|
|
}
|
|
|
|
looped_back:
|
|
if (hdr->segments_left == 0) {
|
|
switch (hdr->type) {
|
|
#if IS_ENABLED(CONFIG_IPV6_MIP6)
|
|
case IPV6_SRCRT_TYPE_2:
|
|
/* Silently discard type 2 header unless it was
|
|
* processed by own
|
|
*/
|
|
if (!addr) {
|
|
__IP6_INC_STATS(net, idev,
|
|
IPSTATS_MIB_INADDRERRORS);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
break;
|
|
#endif
|
|
default:
|
|
break;
|
|
}
|
|
|
|
opt->lastopt = opt->srcrt = skb_network_header_len(skb);
|
|
skb->transport_header += (hdr->hdrlen + 1) << 3;
|
|
opt->dst0 = opt->dst1;
|
|
opt->dst1 = 0;
|
|
opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
|
|
return 1;
|
|
}
|
|
|
|
switch (hdr->type) {
|
|
#if IS_ENABLED(CONFIG_IPV6_MIP6)
|
|
case IPV6_SRCRT_TYPE_2:
|
|
if (accept_source_route < 0)
|
|
goto unknown_rh;
|
|
/* Silently discard invalid RTH type 2 */
|
|
if (hdr->hdrlen != 2 || hdr->segments_left != 1) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
break;
|
|
#endif
|
|
default:
|
|
goto unknown_rh;
|
|
}
|
|
|
|
/*
|
|
* This is the routing header forwarding algorithm from
|
|
* RFC 2460, page 16.
|
|
*/
|
|
|
|
n = hdr->hdrlen >> 1;
|
|
|
|
if (hdr->segments_left > n) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
|
icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
|
|
((&hdr->segments_left) -
|
|
skb_network_header(skb)));
|
|
return -1;
|
|
}
|
|
|
|
/* We are about to mangle packet header. Be careful!
|
|
Do not damage packets queued somewhere.
|
|
*/
|
|
if (skb_cloned(skb)) {
|
|
/* the copy is a forwarded packet */
|
|
if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
|
|
__IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
|
|
IPSTATS_MIB_OUTDISCARDS);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
|
|
}
|
|
|
|
if (skb->ip_summed == CHECKSUM_COMPLETE)
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
|
|
i = n - --hdr->segments_left;
|
|
|
|
rthdr = (struct rt0_hdr *) hdr;
|
|
addr = rthdr->addr;
|
|
addr += i - 1;
|
|
|
|
switch (hdr->type) {
|
|
#if IS_ENABLED(CONFIG_IPV6_MIP6)
|
|
case IPV6_SRCRT_TYPE_2:
|
|
if (xfrm6_input_addr(skb, (xfrm_address_t *)addr,
|
|
(xfrm_address_t *)&ipv6_hdr(skb)->saddr,
|
|
IPPROTO_ROUTING) < 0) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
break;
|
|
#endif
|
|
default:
|
|
break;
|
|
}
|
|
|
|
if (ipv6_addr_is_multicast(addr)) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
|
|
daddr = *addr;
|
|
*addr = ipv6_hdr(skb)->daddr;
|
|
ipv6_hdr(skb)->daddr = daddr;
|
|
|
|
skb_dst_drop(skb);
|
|
ip6_route_input(skb);
|
|
if (skb_dst(skb)->error) {
|
|
skb_push(skb, skb->data - skb_network_header(skb));
|
|
dst_input(skb);
|
|
return -1;
|
|
}
|
|
|
|
if (skb_dst(skb)->dev->flags&IFF_LOOPBACK) {
|
|
if (ipv6_hdr(skb)->hop_limit <= 1) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
|
icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
|
|
0);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
ipv6_hdr(skb)->hop_limit--;
|
|
goto looped_back;
|
|
}
|
|
|
|
skb_push(skb, skb->data - skb_network_header(skb));
|
|
dst_input(skb);
|
|
return -1;
|
|
|
|
unknown_rh:
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
|
icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
|
|
(&hdr->type) - skb_network_header(skb));
|
|
return -1;
|
|
}
|
|
|
|
static const struct inet6_protocol rthdr_protocol = {
|
|
.handler = ipv6_rthdr_rcv,
|
|
.flags = INET6_PROTO_NOPOLICY,
|
|
};
|
|
|
|
static const struct inet6_protocol destopt_protocol = {
|
|
.handler = ipv6_destopt_rcv,
|
|
.flags = INET6_PROTO_NOPOLICY,
|
|
};
|
|
|
|
static const struct inet6_protocol nodata_protocol = {
|
|
.handler = dst_discard,
|
|
.flags = INET6_PROTO_NOPOLICY,
|
|
};
|
|
|
|
int __init ipv6_exthdrs_init(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING);
|
|
if (ret)
|
|
goto out;
|
|
|
|
ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
|
|
if (ret)
|
|
goto out_rthdr;
|
|
|
|
ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE);
|
|
if (ret)
|
|
goto out_destopt;
|
|
|
|
out:
|
|
return ret;
|
|
out_destopt:
|
|
inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
|
|
out_rthdr:
|
|
inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING);
|
|
goto out;
|
|
};
|
|
|
|
void ipv6_exthdrs_exit(void)
|
|
{
|
|
inet6_del_protocol(&nodata_protocol, IPPROTO_NONE);
|
|
inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
|
|
inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING);
|
|
}
|
|
|
|
/**********************************
|
|
Hop-by-hop options.
|
|
**********************************/
|
|
|
|
/*
|
|
* Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input().
|
|
*/
|
|
static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb)
|
|
{
|
|
return skb_dst(skb) ? ip6_dst_idev(skb_dst(skb)) : __in6_dev_get(skb->dev);
|
|
}
|
|
|
|
static inline struct net *ipv6_skb_net(struct sk_buff *skb)
|
|
{
|
|
return skb_dst(skb) ? dev_net(skb_dst(skb)->dev) : dev_net(skb->dev);
|
|
}
|
|
|
|
/* Router Alert as of RFC 2711 */
|
|
|
|
static bool ipv6_hop_ra(struct sk_buff *skb, int optoff)
|
|
{
|
|
const unsigned char *nh = skb_network_header(skb);
|
|
|
|
if (nh[optoff + 1] == 2) {
|
|
IP6CB(skb)->flags |= IP6SKB_ROUTERALERT;
|
|
memcpy(&IP6CB(skb)->ra, nh + optoff + 2, sizeof(IP6CB(skb)->ra));
|
|
return true;
|
|
}
|
|
net_dbg_ratelimited("ipv6_hop_ra: wrong RA length %d\n",
|
|
nh[optoff + 1]);
|
|
kfree_skb(skb);
|
|
return false;
|
|
}
|
|
|
|
/* Jumbo payload */
|
|
|
|
static bool ipv6_hop_jumbo(struct sk_buff *skb, int optoff)
|
|
{
|
|
const unsigned char *nh = skb_network_header(skb);
|
|
struct inet6_dev *idev = __in6_dev_get_safely(skb->dev);
|
|
struct net *net = ipv6_skb_net(skb);
|
|
u32 pkt_len;
|
|
|
|
if (nh[optoff + 1] != 4 || (optoff & 3) != 2) {
|
|
net_dbg_ratelimited("ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n",
|
|
nh[optoff+1]);
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
|
goto drop;
|
|
}
|
|
|
|
pkt_len = ntohl(*(__be32 *)(nh + optoff + 2));
|
|
if (pkt_len <= IPV6_MAXPLEN) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
|
icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2);
|
|
return false;
|
|
}
|
|
if (ipv6_hdr(skb)->payload_len) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
|
icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff);
|
|
return false;
|
|
}
|
|
|
|
if (pkt_len > skb->len - sizeof(struct ipv6hdr)) {
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INTRUNCATEDPKTS);
|
|
goto drop;
|
|
}
|
|
|
|
if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr)))
|
|
goto drop;
|
|
|
|
IP6CB(skb)->flags |= IP6SKB_JUMBOGRAM;
|
|
return true;
|
|
|
|
drop:
|
|
kfree_skb(skb);
|
|
return false;
|
|
}
|
|
|
|
/* CALIPSO RFC 5570 */
|
|
|
|
static bool ipv6_hop_calipso(struct sk_buff *skb, int optoff)
|
|
{
|
|
const unsigned char *nh = skb_network_header(skb);
|
|
|
|
if (nh[optoff + 1] < 8)
|
|
goto drop;
|
|
|
|
if (nh[optoff + 6] * 4 + 8 > nh[optoff + 1])
|
|
goto drop;
|
|
|
|
if (!calipso_validate(skb, nh + optoff))
|
|
goto drop;
|
|
|
|
return true;
|
|
|
|
drop:
|
|
kfree_skb(skb);
|
|
return false;
|
|
}
|
|
|
|
static const struct tlvtype_proc tlvprochopopt_lst[] = {
|
|
{
|
|
.type = IPV6_TLV_ROUTERALERT,
|
|
.func = ipv6_hop_ra,
|
|
},
|
|
{
|
|
.type = IPV6_TLV_JUMBO,
|
|
.func = ipv6_hop_jumbo,
|
|
},
|
|
{
|
|
.type = IPV6_TLV_CALIPSO,
|
|
.func = ipv6_hop_calipso,
|
|
},
|
|
{ -1, }
|
|
};
|
|
|
|
int ipv6_parse_hopopts(struct sk_buff *skb)
|
|
{
|
|
struct inet6_skb_parm *opt = IP6CB(skb);
|
|
struct net *net = dev_net(skb->dev);
|
|
int extlen;
|
|
|
|
/*
|
|
* skb_network_header(skb) is equal to skb->data, and
|
|
* skb_network_header_len(skb) is always equal to
|
|
* sizeof(struct ipv6hdr) by definition of
|
|
* hop-by-hop options.
|
|
*/
|
|
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) ||
|
|
!pskb_may_pull(skb, (sizeof(struct ipv6hdr) +
|
|
((skb_transport_header(skb)[1] + 1) << 3)))) {
|
|
fail_and_free:
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
|
|
extlen = (skb_transport_header(skb)[1] + 1) << 3;
|
|
if (extlen > net->ipv6.sysctl.max_hbh_opts_len)
|
|
goto fail_and_free;
|
|
|
|
opt->flags |= IP6SKB_HOPBYHOP;
|
|
if (ip6_parse_tlv(tlvprochopopt_lst, skb,
|
|
init_net.ipv6.sysctl.max_hbh_opts_cnt)) {
|
|
skb->transport_header += extlen;
|
|
opt = IP6CB(skb);
|
|
opt->nhoff = sizeof(struct ipv6hdr);
|
|
return 1;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Creating outbound headers.
|
|
*
|
|
* "build" functions work when skb is filled from head to tail (datagram)
|
|
* "push" functions work when headers are added from tail to head (tcp)
|
|
*
|
|
* In both cases we assume, that caller reserved enough room
|
|
* for headers.
|
|
*/
|
|
|
|
static void ipv6_push_rthdr0(struct sk_buff *skb, u8 *proto,
|
|
struct ipv6_rt_hdr *opt,
|
|
struct in6_addr **addr_p, struct in6_addr *saddr)
|
|
{
|
|
struct rt0_hdr *phdr, *ihdr;
|
|
int hops;
|
|
|
|
ihdr = (struct rt0_hdr *) opt;
|
|
|
|
phdr = skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3);
|
|
memcpy(phdr, ihdr, sizeof(struct rt0_hdr));
|
|
|
|
hops = ihdr->rt_hdr.hdrlen >> 1;
|
|
|
|
if (hops > 1)
|
|
memcpy(phdr->addr, ihdr->addr + 1,
|
|
(hops - 1) * sizeof(struct in6_addr));
|
|
|
|
phdr->addr[hops - 1] = **addr_p;
|
|
*addr_p = ihdr->addr;
|
|
|
|
phdr->rt_hdr.nexthdr = *proto;
|
|
*proto = NEXTHDR_ROUTING;
|
|
}
|
|
|
|
static void ipv6_push_rthdr4(struct sk_buff *skb, u8 *proto,
|
|
struct ipv6_rt_hdr *opt,
|
|
struct in6_addr **addr_p, struct in6_addr *saddr)
|
|
{
|
|
struct ipv6_sr_hdr *sr_phdr, *sr_ihdr;
|
|
int plen, hops;
|
|
|
|
sr_ihdr = (struct ipv6_sr_hdr *)opt;
|
|
plen = (sr_ihdr->hdrlen + 1) << 3;
|
|
|
|
sr_phdr = skb_push(skb, plen);
|
|
memcpy(sr_phdr, sr_ihdr, sizeof(struct ipv6_sr_hdr));
|
|
|
|
hops = sr_ihdr->first_segment + 1;
|
|
memcpy(sr_phdr->segments + 1, sr_ihdr->segments + 1,
|
|
(hops - 1) * sizeof(struct in6_addr));
|
|
|
|
sr_phdr->segments[0] = **addr_p;
|
|
*addr_p = &sr_ihdr->segments[sr_ihdr->segments_left];
|
|
|
|
if (sr_ihdr->hdrlen > hops * 2) {
|
|
int tlvs_offset, tlvs_length;
|
|
|
|
tlvs_offset = (1 + hops * 2) << 3;
|
|
tlvs_length = (sr_ihdr->hdrlen - hops * 2) << 3;
|
|
memcpy((char *)sr_phdr + tlvs_offset,
|
|
(char *)sr_ihdr + tlvs_offset, tlvs_length);
|
|
}
|
|
|
|
#ifdef CONFIG_IPV6_SEG6_HMAC
|
|
if (sr_has_hmac(sr_phdr)) {
|
|
struct net *net = NULL;
|
|
|
|
if (skb->dev)
|
|
net = dev_net(skb->dev);
|
|
else if (skb->sk)
|
|
net = sock_net(skb->sk);
|
|
|
|
WARN_ON(!net);
|
|
|
|
if (net)
|
|
seg6_push_hmac(net, saddr, sr_phdr);
|
|
}
|
|
#endif
|
|
|
|
sr_phdr->nexthdr = *proto;
|
|
*proto = NEXTHDR_ROUTING;
|
|
}
|
|
|
|
static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto,
|
|
struct ipv6_rt_hdr *opt,
|
|
struct in6_addr **addr_p, struct in6_addr *saddr)
|
|
{
|
|
switch (opt->type) {
|
|
case IPV6_SRCRT_TYPE_0:
|
|
case IPV6_SRCRT_STRICT:
|
|
case IPV6_SRCRT_TYPE_2:
|
|
ipv6_push_rthdr0(skb, proto, opt, addr_p, saddr);
|
|
break;
|
|
case IPV6_SRCRT_TYPE_4:
|
|
ipv6_push_rthdr4(skb, proto, opt, addr_p, saddr);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt)
|
|
{
|
|
struct ipv6_opt_hdr *h = skb_push(skb, ipv6_optlen(opt));
|
|
|
|
memcpy(h, opt, ipv6_optlen(opt));
|
|
h->nexthdr = *proto;
|
|
*proto = type;
|
|
}
|
|
|
|
void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
|
|
u8 *proto,
|
|
struct in6_addr **daddr, struct in6_addr *saddr)
|
|
{
|
|
if (opt->srcrt) {
|
|
ipv6_push_rthdr(skb, proto, opt->srcrt, daddr, saddr);
|
|
/*
|
|
* IPV6_RTHDRDSTOPTS is ignored
|
|
* unless IPV6_RTHDR is set (RFC3542).
|
|
*/
|
|
if (opt->dst0opt)
|
|
ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt);
|
|
}
|
|
if (opt->hopopt)
|
|
ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt);
|
|
}
|
|
|
|
void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto)
|
|
{
|
|
if (opt->dst1opt)
|
|
ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt);
|
|
}
|
|
EXPORT_SYMBOL(ipv6_push_frag_opts);
|
|
|
|
struct ipv6_txoptions *
|
|
ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt)
|
|
{
|
|
struct ipv6_txoptions *opt2;
|
|
|
|
opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC);
|
|
if (opt2) {
|
|
long dif = (char *)opt2 - (char *)opt;
|
|
memcpy(opt2, opt, opt->tot_len);
|
|
if (opt2->hopopt)
|
|
*((char **)&opt2->hopopt) += dif;
|
|
if (opt2->dst0opt)
|
|
*((char **)&opt2->dst0opt) += dif;
|
|
if (opt2->dst1opt)
|
|
*((char **)&opt2->dst1opt) += dif;
|
|
if (opt2->srcrt)
|
|
*((char **)&opt2->srcrt) += dif;
|
|
refcount_set(&opt2->refcnt, 1);
|
|
}
|
|
return opt2;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ipv6_dup_options);
|
|
|
|
static void ipv6_renew_option(int renewtype,
|
|
struct ipv6_opt_hdr **dest,
|
|
struct ipv6_opt_hdr *old,
|
|
struct ipv6_opt_hdr *new,
|
|
int newtype, char **p)
|
|
{
|
|
struct ipv6_opt_hdr *src;
|
|
|
|
src = (renewtype == newtype ? new : old);
|
|
if (!src)
|
|
return;
|
|
|
|
memcpy(*p, src, ipv6_optlen(src));
|
|
*dest = (struct ipv6_opt_hdr *)*p;
|
|
*p += CMSG_ALIGN(ipv6_optlen(*dest));
|
|
}
|
|
|
|
/**
|
|
* ipv6_renew_options - replace a specific ext hdr with a new one.
|
|
*
|
|
* @sk: sock from which to allocate memory
|
|
* @opt: original options
|
|
* @newtype: option type to replace in @opt
|
|
* @newopt: new option of type @newtype to replace (user-mem)
|
|
* @newoptlen: length of @newopt
|
|
*
|
|
* Returns a new set of options which is a copy of @opt with the
|
|
* option type @newtype replaced with @newopt.
|
|
*
|
|
* @opt may be NULL, in which case a new set of options is returned
|
|
* containing just @newopt.
|
|
*
|
|
* @newopt may be NULL, in which case the specified option type is
|
|
* not copied into the new set of options.
|
|
*
|
|
* The new set of options is allocated from the socket option memory
|
|
* buffer of @sk.
|
|
*/
|
|
struct ipv6_txoptions *
|
|
ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt,
|
|
int newtype, struct ipv6_opt_hdr *newopt)
|
|
{
|
|
int tot_len = 0;
|
|
char *p;
|
|
struct ipv6_txoptions *opt2;
|
|
|
|
if (opt) {
|
|
if (newtype != IPV6_HOPOPTS && opt->hopopt)
|
|
tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt));
|
|
if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt)
|
|
tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt));
|
|
if (newtype != IPV6_RTHDR && opt->srcrt)
|
|
tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt));
|
|
if (newtype != IPV6_DSTOPTS && opt->dst1opt)
|
|
tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt));
|
|
}
|
|
|
|
if (newopt)
|
|
tot_len += CMSG_ALIGN(ipv6_optlen(newopt));
|
|
|
|
if (!tot_len)
|
|
return NULL;
|
|
|
|
tot_len += sizeof(*opt2);
|
|
opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC);
|
|
if (!opt2)
|
|
return ERR_PTR(-ENOBUFS);
|
|
|
|
memset(opt2, 0, tot_len);
|
|
refcount_set(&opt2->refcnt, 1);
|
|
opt2->tot_len = tot_len;
|
|
p = (char *)(opt2 + 1);
|
|
|
|
ipv6_renew_option(IPV6_HOPOPTS, &opt2->hopopt,
|
|
(opt ? opt->hopopt : NULL),
|
|
newopt, newtype, &p);
|
|
ipv6_renew_option(IPV6_RTHDRDSTOPTS, &opt2->dst0opt,
|
|
(opt ? opt->dst0opt : NULL),
|
|
newopt, newtype, &p);
|
|
ipv6_renew_option(IPV6_RTHDR,
|
|
(struct ipv6_opt_hdr **)&opt2->srcrt,
|
|
(opt ? (struct ipv6_opt_hdr *)opt->srcrt : NULL),
|
|
newopt, newtype, &p);
|
|
ipv6_renew_option(IPV6_DSTOPTS, &opt2->dst1opt,
|
|
(opt ? opt->dst1opt : NULL),
|
|
newopt, newtype, &p);
|
|
|
|
opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) +
|
|
(opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) +
|
|
(opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0);
|
|
opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0);
|
|
|
|
return opt2;
|
|
}
|
|
|
|
struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
|
|
struct ipv6_txoptions *opt)
|
|
{
|
|
/*
|
|
* ignore the dest before srcrt unless srcrt is being included.
|
|
* --yoshfuji
|
|
*/
|
|
if (opt && opt->dst0opt && !opt->srcrt) {
|
|
if (opt_space != opt) {
|
|
memcpy(opt_space, opt, sizeof(*opt_space));
|
|
opt = opt_space;
|
|
}
|
|
opt->opt_nflen -= ipv6_optlen(opt->dst0opt);
|
|
opt->dst0opt = NULL;
|
|
}
|
|
|
|
return opt;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ipv6_fixup_options);
|
|
|
|
/**
|
|
* fl6_update_dst - update flowi destination address with info given
|
|
* by srcrt option, if any.
|
|
*
|
|
* @fl6: flowi6 for which daddr is to be updated
|
|
* @opt: struct ipv6_txoptions in which to look for srcrt opt
|
|
* @orig: copy of original daddr address if modified
|
|
*
|
|
* Returns NULL if no txoptions or no srcrt, otherwise returns orig
|
|
* and initial value of fl6->daddr set in orig
|
|
*/
|
|
struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
|
|
const struct ipv6_txoptions *opt,
|
|
struct in6_addr *orig)
|
|
{
|
|
if (!opt || !opt->srcrt)
|
|
return NULL;
|
|
|
|
*orig = fl6->daddr;
|
|
|
|
switch (opt->srcrt->type) {
|
|
case IPV6_SRCRT_TYPE_0:
|
|
case IPV6_SRCRT_STRICT:
|
|
case IPV6_SRCRT_TYPE_2:
|
|
fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr;
|
|
break;
|
|
case IPV6_SRCRT_TYPE_4:
|
|
{
|
|
struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)opt->srcrt;
|
|
|
|
fl6->daddr = srh->segments[srh->segments_left];
|
|
break;
|
|
}
|
|
default:
|
|
return NULL;
|
|
}
|
|
|
|
return orig;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fl6_update_dst);
|