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Diffstat (limited to 'net/ipv6/exthdrs.c')
-rw-r--r--net/ipv6/exthdrs.c896
1 files changed, 896 insertions, 0 deletions
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
new file mode 100644
index 00000000..3d641b6e
--- /dev/null
+++ b/net/ipv6/exthdrs.c
@@ -0,0 +1,896 @@
+/*
+ * Extension Header handling for IPv6
+ * Linux INET6 implementation
+ *
+ * Authors:
+ * Pedro Roque <roque@di.fc.ul.pt>
+ * Andi Kleen <ak@muc.de>
+ * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+/* Changes:
+ * yoshfuji : ensure not to overrun while parsing
+ * tlv options.
+ * Mitsuru KANDA @USAGI and: Remove ipv6_parse_exthdrs().
+ * YOSHIFUJI Hideaki @USAGI Register inbound extension header
+ * handlers as inet6_protocol{}.
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/in6.h>
+#include <linux/icmpv6.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+#include <net/dst.h>
+#include <net/sock.h>
+#include <net/snmp.h>
+
+#include <net/ipv6.h>
+#include <net/protocol.h>
+#include <net/transp_v6.h>
+#include <net/rawv6.h>
+#include <net/ndisc.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+#include <net/xfrm.h>
+#endif
+
+#include <asm/uaccess.h>
+
+int ipv6_find_tlv(struct sk_buff *skb, int offset, int type)
+{
+ const unsigned char *nh = skb_network_header(skb);
+ int packet_len = skb->tail - skb->network_header;
+ struct ipv6_opt_hdr *hdr;
+ int len;
+
+ if (offset + 2 > packet_len)
+ goto bad;
+ hdr = (struct ipv6_opt_hdr *)(nh + offset);
+ len = ((hdr->hdrlen + 1) << 3);
+
+ if (offset + len > packet_len)
+ goto bad;
+
+ offset += 2;
+ len -= 2;
+
+ while (len > 0) {
+ int opttype = nh[offset];
+ int optlen;
+
+ if (opttype == type)
+ return offset;
+
+ switch (opttype) {
+ case IPV6_TLV_PAD0:
+ optlen = 1;
+ break;
+ default:
+ optlen = nh[offset + 1] + 2;
+ if (optlen > len)
+ goto bad;
+ break;
+ }
+ offset += optlen;
+ len -= optlen;
+ }
+ /* not_found */
+ bad:
+ return -1;
+}
+EXPORT_SYMBOL_GPL(ipv6_find_tlv);
+
+/*
+ * Parsing tlv encoded headers.
+ *
+ * Parsing function "func" returns 1, if parsing succeed
+ * and 0, if it failed.
+ * It MUST NOT touch skb->h.
+ */
+
+struct tlvtype_proc {
+ int type;
+ int (*func)(struct sk_buff *skb, int offset);
+};
+
+/*********************
+ Generic functions
+ *********************/
+
+/* An unknown option is detected, decide what to do */
+
+static int ip6_tlvopt_unknown(struct sk_buff *skb, int optoff)
+{
+ switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) {
+ case 0: /* ignore */
+ return 1;
+
+ case 1: /* drop packet */
+ break;
+
+ case 3: /* Send ICMP if not a multicast address and drop packet */
+ /* Actually, it is redundant check. icmp_send
+ will recheck in any case.
+ */
+ if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr))
+ break;
+ case 2: /* send ICMP PARM PROB regardless and drop packet */
+ icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff);
+ return 0;
+ }
+
+ kfree_skb(skb);
+ return 0;
+}
+
+/* Parse tlv encoded option header (hop-by-hop or destination) */
+
+static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff *skb)
+{
+ struct tlvtype_proc *curr;
+ const unsigned char *nh = skb_network_header(skb);
+ int off = skb_network_header_len(skb);
+ int len = (skb_transport_header(skb)[1] + 1) << 3;
+
+ if (skb_transport_offset(skb) + len > skb_headlen(skb))
+ goto bad;
+
+ off += 2;
+ len -= 2;
+
+ while (len > 0) {
+ int optlen = nh[off + 1] + 2;
+
+ switch (nh[off]) {
+ case IPV6_TLV_PAD0:
+ optlen = 1;
+ break;
+
+ case IPV6_TLV_PADN:
+ break;
+
+ default: /* Other TLV code so scan list */
+ if (optlen > len)
+ goto bad;
+ for (curr=procs; curr->type >= 0; curr++) {
+ if (curr->type == nh[off]) {
+ /* type specific length/alignment
+ checks will be performed in the
+ func(). */
+ if (curr->func(skb, off) == 0)
+ return 0;
+ break;
+ }
+ }
+ if (curr->type < 0) {
+ if (ip6_tlvopt_unknown(skb, off) == 0)
+ return 0;
+ }
+ break;
+ }
+ off += optlen;
+ len -= optlen;
+ }
+ if (len == 0)
+ return 1;
+bad:
+ kfree_skb(skb);
+ return 0;
+}
+
+/*****************************
+ Destination options header.
+ *****************************/
+
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+static int ipv6_dest_hao(struct sk_buff *skb, int optoff)
+{
+ struct ipv6_destopt_hao *hao;
+ struct inet6_skb_parm *opt = IP6CB(skb);
+ struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+ struct in6_addr tmp_addr;
+ int ret;
+
+ if (opt->dsthao) {
+ LIMIT_NETDEBUG(KERN_DEBUG "hao duplicated\n");
+ goto discard;
+ }
+ opt->dsthao = opt->dst1;
+ opt->dst1 = 0;
+
+ hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff);
+
+ if (hao->length != 16) {
+ LIMIT_NETDEBUG(
+ KERN_DEBUG "hao invalid option length = %d\n", hao->length);
+ goto discard;
+ }
+
+ if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) {
+ LIMIT_NETDEBUG(
+ KERN_DEBUG "hao is not an unicast addr: %pI6\n", &hao->addr);
+ goto discard;
+ }
+
+ ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr,
+ (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS);
+ if (unlikely(ret < 0))
+ goto discard;
+
+ if (skb_cloned(skb)) {
+ if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
+ goto discard;
+
+ /* update all variable using below by copied skbuff */
+ hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) +
+ optoff);
+ ipv6h = ipv6_hdr(skb);
+ }
+
+ if (skb->ip_summed == CHECKSUM_COMPLETE)
+ skb->ip_summed = CHECKSUM_NONE;
+
+ tmp_addr = ipv6h->saddr;
+ ipv6h->saddr = hao->addr;
+ hao->addr = tmp_addr;
+
+ if (skb->tstamp.tv64 == 0)
+ __net_timestamp(skb);
+
+ return 1;
+
+ discard:
+ kfree_skb(skb);
+ return 0;
+}
+#endif
+
+static struct tlvtype_proc tlvprocdestopt_lst[] = {
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+ {
+ .type = IPV6_TLV_HAO,
+ .func = ipv6_dest_hao,
+ },
+#endif
+ {-1, NULL}
+};
+
+static int ipv6_destopt_rcv(struct sk_buff *skb)
+{
+ struct inet6_skb_parm *opt = IP6CB(skb);
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+ __u16 dstbuf;
+#endif
+ struct dst_entry *dst = skb_dst(skb);
+
+ 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_BH(dev_net(dst->dev), ip6_dst_idev(dst),
+ IPSTATS_MIB_INHDRERRORS);
+ kfree_skb(skb);
+ return -1;
+ }
+
+ opt->lastopt = opt->dst1 = skb_network_header_len(skb);
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+ dstbuf = opt->dst1;
+#endif
+
+ if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) {
+ skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
+ opt = IP6CB(skb);
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+ opt->nhoff = dstbuf;
+#else
+ opt->nhoff = opt->dst1;
+#endif
+ return 1;
+ }
+
+ IP6_INC_STATS_BH(dev_net(dst->dev),
+ ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS);
+ return -1;
+}
+
+/********************************
+ Routing header.
+ ********************************/
+
+/* called with rcu_read_lock() */
+static int ipv6_rthdr_rcv(struct sk_buff *skb)
+{
+ struct inet6_skb_parm *opt = IP6CB(skb);
+ struct in6_addr *addr = NULL;
+ struct in6_addr daddr;
+ struct inet6_dev *idev;
+ 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_BH(net, ip6_dst_idev(skb_dst(skb)),
+ 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_BH(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_INADDRERRORS);
+ kfree_skb(skb);
+ return -1;
+ }
+
+looped_back:
+ if (hdr->segments_left == 0) {
+ switch (hdr->type) {
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+ case IPV6_SRCRT_TYPE_2:
+ /* Silently discard type 2 header unless it was
+ * processed by own
+ */
+ if (!addr) {
+ IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+ 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 defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+ 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_BH(net, ip6_dst_idev(skb_dst(skb)),
+ 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_BH(net, ip6_dst_idev(skb_dst(skb)),
+ 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_BH(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 defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+ 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_BH(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_INADDRERRORS);
+ kfree_skb(skb);
+ return -1;
+ }
+ if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) {
+ IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_INADDRERRORS);
+ kfree_skb(skb);
+ return -1;
+ }
+ break;
+#endif
+ default:
+ break;
+ }
+
+ if (ipv6_addr_is_multicast(addr)) {
+ IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
+ 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_BH(net, ip6_dst_idev(skb_dst(skb)),
+ 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_BH(net, ip6_dst_idev(skb_dst(skb)), 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 | INET6_PROTO_GSO_EXTHDR,
+};
+
+static const struct inet6_protocol destopt_protocol = {
+ .handler = ipv6_destopt_rcv,
+ .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR,
+};
+
+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_rthdr:
+ inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING);
+out_destopt:
+ inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
+ 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 int ipv6_hop_ra(struct sk_buff *skb, int optoff)
+{
+ const unsigned char *nh = skb_network_header(skb);
+
+ if (nh[optoff + 1] == 2) {
+ IP6CB(skb)->ra = optoff;
+ return 1;
+ }
+ LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n",
+ nh[optoff + 1]);
+ kfree_skb(skb);
+ return 0;
+}
+
+/* Jumbo payload */
+
+static int ipv6_hop_jumbo(struct sk_buff *skb, int optoff)
+{
+ const unsigned char *nh = skb_network_header(skb);
+ struct net *net = ipv6_skb_net(skb);
+ u32 pkt_len;
+
+ if (nh[optoff + 1] != 4 || (optoff & 3) != 2) {
+ LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n",
+ nh[optoff+1]);
+ IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
+ IPSTATS_MIB_INHDRERRORS);
+ goto drop;
+ }
+
+ pkt_len = ntohl(*(__be32 *)(nh + optoff + 2));
+ if (pkt_len <= IPV6_MAXPLEN) {
+ IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
+ IPSTATS_MIB_INHDRERRORS);
+ icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2);
+ return 0;
+ }
+ if (ipv6_hdr(skb)->payload_len) {
+ IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
+ IPSTATS_MIB_INHDRERRORS);
+ icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff);
+ return 0;
+ }
+
+ if (pkt_len > skb->len - sizeof(struct ipv6hdr)) {
+ IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
+ IPSTATS_MIB_INTRUNCATEDPKTS);
+ goto drop;
+ }
+
+ if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr)))
+ goto drop;
+
+ return 1;
+
+drop:
+ kfree_skb(skb);
+ return 0;
+}
+
+static struct tlvtype_proc tlvprochopopt_lst[] = {
+ {
+ .type = IPV6_TLV_ROUTERALERT,
+ .func = ipv6_hop_ra,
+ },
+ {
+ .type = IPV6_TLV_JUMBO,
+ .func = ipv6_hop_jumbo,
+ },
+ { -1, }
+};
+
+int ipv6_parse_hopopts(struct sk_buff *skb)
+{
+ struct inet6_skb_parm *opt = IP6CB(skb);
+
+ /*
+ * 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)))) {
+ kfree_skb(skb);
+ return -1;
+ }
+
+ opt->hop = sizeof(struct ipv6hdr);
+ if (ip6_parse_tlv(tlvprochopopt_lst, skb)) {
+ skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
+ 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_rthdr(struct sk_buff *skb, u8 *proto,
+ struct ipv6_rt_hdr *opt,
+ struct in6_addr **addr_p)
+{
+ struct rt0_hdr *phdr, *ihdr;
+ int hops;
+
+ ihdr = (struct rt0_hdr *) opt;
+
+ phdr = (struct rt0_hdr *) 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_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt)
+{
+ struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)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)
+{
+ if (opt->srcrt) {
+ ipv6_push_rthdr(skb, proto, opt->srcrt, daddr);
+ /*
+ * 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);
+}
+
+EXPORT_SYMBOL(ipv6_push_nfrag_opts);
+
+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);
+}
+
+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;
+ }
+ return opt2;
+}
+
+EXPORT_SYMBOL_GPL(ipv6_dup_options);
+
+static int ipv6_renew_option(void *ohdr,
+ struct ipv6_opt_hdr __user *newopt, int newoptlen,
+ int inherit,
+ struct ipv6_opt_hdr **hdr,
+ char **p)
+{
+ if (inherit) {
+ if (ohdr) {
+ memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr));
+ *hdr = (struct ipv6_opt_hdr *)*p;
+ *p += CMSG_ALIGN(ipv6_optlen(*(struct ipv6_opt_hdr **)hdr));
+ }
+ } else {
+ if (newopt) {
+ if (copy_from_user(*p, newopt, newoptlen))
+ return -EFAULT;
+ *hdr = (struct ipv6_opt_hdr *)*p;
+ if (ipv6_optlen(*(struct ipv6_opt_hdr **)hdr) > newoptlen)
+ return -EINVAL;
+ *p += CMSG_ALIGN(newoptlen);
+ }
+ }
+ return 0;
+}
+
+struct ipv6_txoptions *
+ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt,
+ int newtype,
+ struct ipv6_opt_hdr __user *newopt, int newoptlen)
+{
+ int tot_len = 0;
+ char *p;
+ struct ipv6_txoptions *opt2;
+ int err;
+
+ 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 && newoptlen)
+ tot_len += CMSG_ALIGN(newoptlen);
+
+ 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);
+
+ opt2->tot_len = tot_len;
+ p = (char *)(opt2 + 1);
+
+ err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen,
+ newtype != IPV6_HOPOPTS,
+ &opt2->hopopt, &p);
+ if (err)
+ goto out;
+
+ err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen,
+ newtype != IPV6_RTHDRDSTOPTS,
+ &opt2->dst0opt, &p);
+ if (err)
+ goto out;
+
+ err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen,
+ newtype != IPV6_RTHDR,
+ (struct ipv6_opt_hdr **)&opt2->srcrt, &p);
+ if (err)
+ goto out;
+
+ err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen,
+ newtype != IPV6_DSTOPTS,
+ &opt2->dst1opt, &p);
+ if (err)
+ goto out;
+
+ 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;
+out:
+ sock_kfree_s(sk, opt2, opt2->tot_len);
+ return ERR_PTR(err);
+}
+
+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;
+}
+
+/**
+ * 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;
+ fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr;
+ return orig;
+}
+
+EXPORT_SYMBOL_GPL(fl6_update_dst);
generated by cgit (git 2.34.1) at 2024-12-20 11:02:47 +0000