zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/net/ipv6/ip6_output.c b/ap/os/linux/linux-3.4.x/net/ipv6/ip6_output.c
new file mode 100755
index 0000000..daadf4c
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/net/ipv6/ip6_output.c
@@ -0,0 +1,1706 @@
+/*
+ * IPv6 output functions
+ * Linux INET6 implementation
+ *
+ * Authors:
+ * Pedro Roque <roque@di.fc.ul.pt>
+ *
+ * Based on linux/net/ipv4/ip_output.c
+ *
+ * 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:
+ * A.N.Kuznetsov : airthmetics in fragmentation.
+ * extension headers are implemented.
+ * route changes now work.
+ * ip6_forward does not confuse sniffers.
+ * etc.
+ *
+ * H. von Brand : Added missing #include <linux/string.h>
+ * Imran Patel : frag id should be in NBO
+ * Kazunori MIYAZAWA @USAGI
+ * : add ip6_append_data and related functions
+ * for datagram xmit
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/socket.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/in6.h>
+#include <linux/tcp.h>
+#include <linux/route.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include <linux/netfilter.h>
+#include <linux/netfilter_ipv6.h>
+
+#include <net/sock.h>
+#include <net/snmp.h>
+
+#include <net/ipv6.h>
+#include <net/ndisc.h>
+#include <net/protocol.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#include <net/rawv6.h>
+#include <net/icmp.h>
+#include <net/xfrm.h>
+#include <net/checksum.h>
+#include <linux/mroute6.h>
+
+#include <net/SI/fast_common.h>
+
+
+int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
+
+int __ip6_local_out(struct sk_buff *skb)
+{
+ int len;
+
+ len = skb->len - sizeof(struct ipv6hdr);
+ if (len > IPV6_MAXPLEN)
+ len = 0;
+ ipv6_hdr(skb)->payload_len = htons(len);
+
+ return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL,
+ skb_dst(skb)->dev, dst_output);
+}
+
+int ip6_local_out(struct sk_buff *skb)
+{
+ int err;
+
+ err = __ip6_local_out(skb);
+ if (likely(err == 1))
+ err = dst_output(skb);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(ip6_local_out);
+
+/* dev_loopback_xmit for use with netfilter. */
+static int ip6_dev_loopback_xmit(struct sk_buff *newskb)
+{
+ skb_reset_mac_header(newskb);
+ __skb_pull(newskb, skb_network_offset(newskb));
+ newskb->pkt_type = PACKET_LOOPBACK;
+ newskb->ip_summed = CHECKSUM_UNNECESSARY;
+ WARN_ON(!skb_dst(newskb));
+
+ netif_rx_ni(newskb);
+ return 0;
+}
+
+static int ip6_finish_output2(struct sk_buff *skb)
+{
+ struct dst_entry *dst = skb_dst(skb);
+ struct net_device *dev = dst->dev;
+ struct neighbour *neigh;
+
+ skb->protocol = htons(ETH_P_IPV6);
+ skb->dev = dev;
+
+ if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
+ struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
+
+ if (!(dev->flags & IFF_LOOPBACK) && sk_mc_loop(skb->sk) &&
+ ((mroute6_socket(dev_net(dev), skb) &&
+ !(IP6CB(skb)->flags & IP6SKB_FORWARDED)) ||
+ ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr,
+ &ipv6_hdr(skb)->saddr))) {
+ struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
+
+ /* Do not check for IFF_ALLMULTI; multicast routing
+ is not supported in any case.
+ */
+ if (newskb)
+ NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING,
+ newskb, NULL, newskb->dev,
+ ip6_dev_loopback_xmit);
+
+ if (ipv6_hdr(skb)->hop_limit == 0) {
+ IP6_INC_STATS(dev_net(dev), idev,
+ IPSTATS_MIB_OUTDISCARDS);
+ kfree_skb(skb);
+ return 0;
+ }
+ }
+
+ IP6_UPD_PO_STATS(dev_net(dev), idev, IPSTATS_MIB_OUTMCAST,
+ skb->len);
+ }
+
+ rcu_read_lock();
+ neigh = dst_get_neighbour_noref(dst);
+ if (neigh) {
+ int res = neigh_output(neigh, skb);
+
+ rcu_read_unlock();
+ return res;
+ }
+ rcu_read_unlock();
+ IP6_INC_STATS(dev_net(dst->dev),
+ ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+static int ip6_finish_output(struct sk_buff *skb)
+{
+ if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
+ dst_allfrag(skb_dst(skb)))
+ return ip6_fragment(skb, ip6_finish_output2);
+ else
+ return ip6_finish_output2(skb);
+}
+
+int ip6_output(struct sk_buff *skb)
+{
+ struct net_device *dev = skb_dst(skb)->dev;
+ struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
+ if (unlikely(idev->cnf.disable_ipv6)) {
+ IP6_INC_STATS(dev_net(dev), idev,
+ IPSTATS_MIB_OUTDISCARDS);
+ kfree_skb(skb);
+ return 0;
+ }
+
+ return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING, skb, NULL, dev,
+ ip6_finish_output,
+ !(IP6CB(skb)->flags & IP6SKB_REROUTED));
+}
+
+/*
+ * xmit an sk_buff (used by TCP, SCTP and DCCP)
+ */
+
+int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
+ struct ipv6_txoptions *opt, int tclass)
+{
+ struct net *net = sock_net(sk);
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct in6_addr *first_hop = &fl6->daddr;
+ struct dst_entry *dst = skb_dst(skb);
+ struct ipv6hdr *hdr;
+ u8 proto = fl6->flowi6_proto;
+ int seg_len = skb->len;
+ int hlimit = -1;
+ u32 mtu;
+
+ if (opt) {
+ unsigned int head_room;
+
+ /* First: exthdrs may take lots of space (~8K for now)
+ MAX_HEADER is not enough.
+ */
+ head_room = opt->opt_nflen + opt->opt_flen;
+ seg_len += head_room;
+ head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev);
+
+ if (skb_headroom(skb) < head_room) {
+ struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room);
+ if (skb2 == NULL) {
+ IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_OUTDISCARDS);
+ kfree_skb(skb);
+ return -ENOBUFS;
+ }
+ kfree_skb(skb);
+ skb = skb2;
+ skb_set_owner_w(skb, sk);
+ }
+ if (opt->opt_flen)
+ ipv6_push_frag_opts(skb, opt, &proto);
+ if (opt->opt_nflen)
+ ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop);
+ }
+
+ skb_push(skb, sizeof(struct ipv6hdr));
+ skb_reset_network_header(skb);
+ hdr = ipv6_hdr(skb);
+
+ /*
+ * Fill in the IPv6 header
+ */
+ if (np)
+ hlimit = np->hop_limit;
+ if (hlimit < 0)
+ hlimit = ip6_dst_hoplimit(dst);
+
+ *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | fl6->flowlabel;
+
+ hdr->payload_len = htons(seg_len);
+ hdr->nexthdr = proto;
+ hdr->hop_limit = hlimit;
+
+ hdr->saddr = fl6->saddr;
+ hdr->daddr = *first_hop;
+
+ skb->priority = sk->sk_priority;
+ skb->mark = sk->sk_mark;
+
+ mtu = dst_mtu(dst);
+ if ((skb->len <= mtu) || skb->local_df || skb_is_gso(skb)) {
+ IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_OUT, skb->len);
+ return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL,
+ dst->dev, dst_output);
+ }
+
+ if (net_ratelimit())
+ printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n");
+ skb->dev = dst->dev;
+ icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+ IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS);
+ kfree_skb(skb);
+ return -EMSGSIZE;
+}
+
+EXPORT_SYMBOL(ip6_xmit);
+
+/*
+ * To avoid extra problems ND packets are send through this
+ * routine. It's code duplication but I really want to avoid
+ * extra checks since ipv6_build_header is used by TCP (which
+ * is for us performance critical)
+ */
+
+int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev,
+ const struct in6_addr *saddr, const struct in6_addr *daddr,
+ int proto, int len)
+{
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct ipv6hdr *hdr;
+
+ skb->protocol = htons(ETH_P_IPV6);
+ skb->dev = dev;
+
+ skb_reset_network_header(skb);
+ skb_put(skb, sizeof(struct ipv6hdr));
+ hdr = ipv6_hdr(skb);
+
+ *(__be32*)hdr = htonl(0x60000000);
+
+ hdr->payload_len = htons(len);
+ hdr->nexthdr = proto;
+ hdr->hop_limit = np->hop_limit;
+
+ hdr->saddr = *saddr;
+ hdr->daddr = *daddr;
+
+ return 0;
+}
+
+static int ip6_call_ra_chain(struct sk_buff *skb, int sel)
+{
+ struct ip6_ra_chain *ra;
+ struct sock *last = NULL;
+
+ read_lock(&ip6_ra_lock);
+ for (ra = ip6_ra_chain; ra; ra = ra->next) {
+ struct sock *sk = ra->sk;
+ if (sk && ra->sel == sel &&
+ (!sk->sk_bound_dev_if ||
+ sk->sk_bound_dev_if == skb->dev->ifindex)) {
+ if (last) {
+ struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
+ if (skb2)
+ rawv6_rcv(last, skb2);
+ }
+ last = sk;
+ }
+ }
+
+ if (last) {
+ rawv6_rcv(last, skb);
+ read_unlock(&ip6_ra_lock);
+ return 1;
+ }
+ read_unlock(&ip6_ra_lock);
+ return 0;
+}
+
+static int ip6_forward_proxy_check(struct sk_buff *skb)
+{
+ struct ipv6hdr *hdr = ipv6_hdr(skb);
+ u8 nexthdr = hdr->nexthdr;
+ __be16 frag_off;
+ int offset;
+
+ if (ipv6_ext_hdr(nexthdr)) {
+ offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr, &frag_off);
+ if (offset < 0)
+ return 0;
+ } else
+ offset = sizeof(struct ipv6hdr);
+
+ if (nexthdr == IPPROTO_ICMPV6) {
+ struct icmp6hdr *icmp6;
+
+ if (!pskb_may_pull(skb, (skb_network_header(skb) +
+ offset + 1 - skb->data)))
+ return 0;
+
+ icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
+
+ switch (icmp6->icmp6_type) {
+ case NDISC_ROUTER_SOLICITATION:
+ case NDISC_ROUTER_ADVERTISEMENT:
+ case NDISC_NEIGHBOUR_SOLICITATION:
+ case NDISC_NEIGHBOUR_ADVERTISEMENT:
+ case NDISC_REDIRECT:
+ /* For reaction involving unicast neighbor discovery
+ * message destined to the proxied address, pass it to
+ * input function.
+ */
+ return 1;
+ default:
+ break;
+ }
+ }
+
+ /*
+ * The proxying router can't forward traffic sent to a link-local
+ * address, so signal the sender and discard the packet. This
+ * behavior is clarified by the MIPv6 specification.
+ */
+ if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) {
+ dst_link_failure(skb);
+ return -1;
+ }
+
+ return 0;
+}
+
+static inline int ip6_forward_finish(struct sk_buff *skb)
+{
+ return dst_output(skb);
+}
+
+int ip6_forward(struct sk_buff *skb)
+{
+ struct dst_entry *dst = skb_dst(skb);
+ struct ipv6hdr *hdr = ipv6_hdr(skb);
+ struct inet6_skb_parm *opt = IP6CB(skb);
+ struct net *net = dev_net(dst->dev);
+ u32 mtu;
+
+ if (net->ipv6.devconf_all->forwarding == 0)
+ goto error;
+
+ if (skb_warn_if_lro(skb))
+ goto drop;
+
+ if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
+ IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
+ goto drop;
+ }
+
+ if (skb->pkt_type != PACKET_HOST)
+ goto drop;
+
+ skb_forward_csum(skb);
+
+ /*
+ * We DO NOT make any processing on
+ * RA packets, pushing them to user level AS IS
+ * without ane WARRANTY that application will be able
+ * to interpret them. The reason is that we
+ * cannot make anything clever here.
+ *
+ * We are not end-node, so that if packet contains
+ * AH/ESP, we cannot make anything.
+ * Defragmentation also would be mistake, RA packets
+ * cannot be fragmented, because there is no warranty
+ * that different fragments will go along one path. --ANK
+ */
+ if (opt->ra) {
+ u8 *ptr = skb_network_header(skb) + opt->ra;
+ if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3]))
+ return 0;
+ }
+
+ /*
+ * check and decrement ttl
+ */
+ if (hdr->hop_limit <= 1) {
+ /* Force OUTPUT device used as source address */
+ skb->dev = dst->dev;
+ icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, 0);
+ IP6_INC_STATS_BH(net,
+ ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS);
+
+ kfree_skb(skb);
+ return -ETIMEDOUT;
+ }
+
+ /* XXX: idev->cnf.proxy_ndp? */
+ if (net->ipv6.devconf_all->proxy_ndp &&
+ pneigh_lookup(&nd_tbl, net, &hdr->daddr, skb->dev, 0)) {
+ int proxied = ip6_forward_proxy_check(skb);
+ if (proxied > 0)
+ return ip6_input(skb);
+ else if (proxied < 0) {
+ IP6_INC_STATS(net, ip6_dst_idev(dst),
+ IPSTATS_MIB_INDISCARDS);
+ goto drop;
+ }
+ }
+
+ if (!xfrm6_route_forward(skb)) {
+ IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
+ goto drop;
+ }
+ dst = skb_dst(skb);
+
+ /* IPv6 specs say nothing about it, but it is clear that we cannot
+ send redirects to source routed frames.
+ We don't send redirects to frames decapsulated from IPsec.
+ */
+ if (skb->dev == dst->dev && opt->srcrt == 0 && !skb_sec_path(skb)) {
+ struct in6_addr *target = NULL;
+ struct rt6_info *rt;
+
+ /*
+ * incoming and outgoing devices are the same
+ * send a redirect.
+ */
+
+ rt = (struct rt6_info *) dst;
+ if (rt->rt6i_flags & RTF_GATEWAY)
+ target = &rt->rt6i_gateway;
+ else
+ target = &hdr->daddr;
+
+ if (!rt->rt6i_peer)
+ rt6_bind_peer(rt, 1);
+
+ /* Limit redirects both by destination (here)
+ and by source (inside ndisc_send_redirect)
+ */
+ if (inet_peer_xrlim_allow(rt->rt6i_peer, 1*HZ))
+ ndisc_send_redirect(skb, target);
+ } else {
+ int addrtype = ipv6_addr_type(&hdr->saddr);
+
+ /* This check is security critical. */
+ if (addrtype == IPV6_ADDR_ANY ||
+ addrtype & (IPV6_ADDR_MULTICAST | IPV6_ADDR_LOOPBACK))
+ goto error;
+ if (addrtype & IPV6_ADDR_LINKLOCAL) {
+ icmpv6_send(skb, ICMPV6_DEST_UNREACH,
+ ICMPV6_NOT_NEIGHBOUR, 0);
+ goto error;
+ }
+ }
+
+ mtu = dst_mtu(dst);
+ if (mtu < IPV6_MIN_MTU)
+ mtu = IPV6_MIN_MTU;
+
+ if (skb->len > mtu && !skb_is_gso(skb)) {
+ /* Again, force OUTPUT device used as source address */
+ skb->dev = dst->dev;
+ icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+ IP6_INC_STATS_BH(net,
+ ip6_dst_idev(dst), IPSTATS_MIB_INTOOBIGERRORS);
+ IP6_INC_STATS_BH(net,
+ ip6_dst_idev(dst), IPSTATS_MIB_FRAGFAILS);
+ kfree_skb(skb);
+ return -EMSGSIZE;
+ }
+
+ if (skb_cow(skb, dst->dev->hard_header_len)) {
+ IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS);
+ goto drop;
+ }
+
+ hdr = ipv6_hdr(skb);
+
+ /* Mangling hops number delayed to point after skb COW */
+
+ hdr->hop_limit--;
+
+ IP6_INC_STATS_BH(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS);
+ return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD, skb, skb->dev, dst->dev,
+ ip6_forward_finish);
+
+error:
+ IP6_INC_STATS_BH(net, ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS);
+drop:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
+{
+ to->pkt_type = from->pkt_type;
+ to->priority = from->priority;
+ to->protocol = from->protocol;
+ skb_dst_drop(to);
+ skb_dst_set(to, dst_clone(skb_dst(from)));
+ to->dev = from->dev;
+ to->mark = from->mark;
+
+#ifdef CONFIG_NET_SCHED
+ to->tc_index = from->tc_index;
+#endif
+ nf_copy(to, from);
+#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
+ defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)
+ to->nf_trace = from->nf_trace;
+#endif
+ skb_copy_secmark(to, from);
+}
+
+int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr)
+{
+ u16 offset = sizeof(struct ipv6hdr);
+ //struct ipv6_opt_hdr *exthdr =//CVE-2017-9074
+ //(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
+ unsigned int packet_len = skb->tail - skb->network_header;
+ int found_rhdr = 0;
+ *nexthdr = &ipv6_hdr(skb)->nexthdr;
+
+ //while (offset + 1 <= packet_len) {//CVE-2017-9074
+ while (offset <= packet_len) {
+ struct ipv6_opt_hdr *exthdr;//CVE-2017-9074
+ switch (**nexthdr) {
+
+ case NEXTHDR_HOP:
+ break;
+ case NEXTHDR_ROUTING:
+ found_rhdr = 1;
+ break;
+ case NEXTHDR_DEST:
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+ if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
+ break;
+#endif
+ if (found_rhdr)
+ return offset;
+ break;
+ default :
+ return offset;
+ }
+
+ //offset += ipv6_optlen(exthdr);//CVE-2017-9074
+ //*nexthdr = &exthdr->nexthdr;
+ if (offset + sizeof(struct ipv6_opt_hdr) > packet_len)
+ return -EINVAL;//CVE-2017-9074
+ exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) +
+ offset);
+ offset += ipv6_optlen(exthdr);
+ *nexthdr = &exthdr->nexthdr;//CVE-2017-9074
+ }
+
+ //return offset;
+ return -EINVAL;//CVE-2017-9074
+}
+
+void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt)
+{
+ static u32 ip6_idents_hashrnd __read_mostly;
+ static bool hashrnd_initialized = false;
+ u32 hash, id;
+
+ if (unlikely(!hashrnd_initialized)) {
+ hashrnd_initialized = true;
+ get_random_bytes(&ip6_idents_hashrnd, sizeof(ip6_idents_hashrnd));
+ }
+ hash = __ipv6_addr_jhash(&rt->rt6i_dst.addr, ip6_idents_hashrnd);
+ hash = __ipv6_addr_jhash(&rt->rt6i_src.addr, hash);
+
+ id = ip_idents_reserve(hash, 1);
+ fhdr->identification = htonl(id);
+}
+
+int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
+{
+ struct sk_buff *frag;
+ struct rt6_info *rt = (struct rt6_info*)skb_dst(skb);
+ struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
+ struct ipv6hdr *tmp_hdr;
+ struct frag_hdr *fh;
+ unsigned int mtu, hlen, left, len;
+ int hroom, troom;
+ __be32 frag_id = 0;
+ int ptr, offset = 0, err=0;
+ u8 *prevhdr, nexthdr = 0;
+ struct net *net = dev_net(skb_dst(skb)->dev);
+
+ hlen = ip6_find_1stfragopt(skb, &prevhdr);
+ if (hlen < 0) {//CVE-2017-9074
+ err = hlen;
+ goto fail;
+ }
+ nexthdr = *prevhdr;
+
+ mtu = ip6_skb_dst_mtu(skb);
+
+ /* We must not fragment if the socket is set to force MTU discovery
+ * or if the skb it not generated by a local socket.
+ */
+ if (!skb->local_df && skb->len > mtu) {
+ skb->dev = skb_dst(skb)->dev;
+ icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+ IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_FRAGFAILS);
+ kfree_skb(skb);
+ return -EMSGSIZE;
+ }
+
+ if (np && np->frag_size < mtu) {
+ if (np->frag_size)
+ mtu = np->frag_size;
+ }
+ mtu -= hlen + sizeof(struct frag_hdr);
+
+ if (skb_has_frag_list(skb)) {
+ int first_len = skb_pagelen(skb);
+ struct sk_buff *frag2;
+
+ if (first_len - hlen > mtu ||
+ ((first_len - hlen) & 7) ||
+ skb_cloned(skb))
+ goto slow_path;
+
+ skb_walk_frags(skb, frag) {
+ /* Correct geometry. */
+ if (frag->len > mtu ||
+ ((frag->len & 7) && frag->next) ||
+ skb_headroom(frag) < hlen)
+ goto slow_path_clean;
+
+ /* Partially cloned skb? */
+ if (skb_shared(frag))
+ goto slow_path_clean;
+
+ BUG_ON(frag->sk);
+ if (skb->sk) {
+ frag->sk = skb->sk;
+ frag->destructor = sock_wfree;
+ }
+ skb->truesize -= frag->truesize;
+ }
+
+ err = 0;
+ offset = 0;
+ frag = skb_shinfo(skb)->frag_list;
+ skb_frag_list_init(skb);
+ /* BUILD HEADER */
+
+ *prevhdr = NEXTHDR_FRAGMENT;
+ tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC);
+ if (!tmp_hdr) {
+ IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_FRAGFAILS);
+ return -ENOMEM;
+ }
+
+ __skb_pull(skb, hlen);
+ fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr));
+ __skb_push(skb, hlen);
+ skb_reset_network_header(skb);
+ memcpy(skb_network_header(skb), tmp_hdr, hlen);
+
+ ipv6_select_ident(fh, rt);
+ fh->nexthdr = nexthdr;
+ fh->reserved = 0;
+ fh->frag_off = htons(IP6_MF);
+ frag_id = fh->identification;
+
+ first_len = skb_pagelen(skb);
+ skb->data_len = first_len - skb_headlen(skb);
+ skb->len = first_len;
+ ipv6_hdr(skb)->payload_len = htons(first_len -
+ sizeof(struct ipv6hdr));
+
+ dst_hold(&rt->dst);
+
+ for (;;) {
+ /* Prepare header of the next frame,
+ * before previous one went down. */
+ if (frag) {
+ frag->ip_summed = CHECKSUM_NONE;
+ skb_reset_transport_header(frag);
+ fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr));
+ __skb_push(frag, hlen);
+ skb_reset_network_header(frag);
+ memcpy(skb_network_header(frag), tmp_hdr,
+ hlen);
+ offset += skb->len - hlen - sizeof(struct frag_hdr);
+ fh->nexthdr = nexthdr;
+ fh->reserved = 0;
+ fh->frag_off = htons(offset);
+ if (frag->next != NULL)
+ fh->frag_off |= htons(IP6_MF);
+ fh->identification = frag_id;
+ ipv6_hdr(frag)->payload_len =
+ htons(frag->len -
+ sizeof(struct ipv6hdr));
+ ip6_copy_metadata(frag, skb);
+ }
+
+ err = output(skb);
+ if(!err)
+ IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
+ IPSTATS_MIB_FRAGCREATES);
+
+ if (err || !frag)
+ break;
+
+ skb = frag;
+ frag = skb->next;
+ skb->next = NULL;
+ }
+
+ kfree(tmp_hdr);
+
+ if (err == 0) {
+ IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
+ IPSTATS_MIB_FRAGOKS);
+ dst_release(&rt->dst);
+ return 0;
+ }
+
+ while (frag) {
+ skb = frag->next;
+ kfree_skb(frag);
+ frag = skb;
+ }
+
+ IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
+ IPSTATS_MIB_FRAGFAILS);
+ dst_release(&rt->dst);
+ return err;
+
+slow_path_clean:
+ skb_walk_frags(skb, frag2) {
+ if (frag2 == frag)
+ break;
+ frag2->sk = NULL;
+ frag2->destructor = NULL;
+ skb->truesize += frag2->truesize;
+ }
+ }
+
+slow_path:
+ left = skb->len - hlen; /* Space per frame */
+ ptr = hlen; /* Where to start from */
+
+ /*
+ * Fragment the datagram.
+ */
+
+ *prevhdr = NEXTHDR_FRAGMENT;
+ hroom = LL_RESERVED_SPACE(rt->dst.dev);
+ troom = rt->dst.dev->needed_tailroom;
+
+ /*
+ * Keep copying data until we run out.
+ */
+ while(left > 0) {
+ len = left;
+ /* IF: it doesn't fit, use 'mtu' - the data space left */
+ if (len > mtu)
+ len = mtu;
+ /* IF: we are not sending up to and including the packet end
+ then align the next start on an eight byte boundary */
+ if (len < left) {
+ len &= ~7;
+ }
+ /*
+ * Allocate buffer.
+ */
+
+ if ((frag = alloc_skb(len + hlen + sizeof(struct frag_hdr) +
+ hroom + troom, GFP_ATOMIC)) == NULL) {
+ NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n");
+ IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_FRAGFAILS);
+ err = -ENOMEM;
+ goto fail;
+ }
+
+ /*
+ * Set up data on packet
+ */
+
+ ip6_copy_metadata(frag, skb);
+ skb_reserve(frag, hroom);
+ skb_put(frag, len + hlen + sizeof(struct frag_hdr));
+ skb_reset_network_header(frag);
+ fh = (struct frag_hdr *)(skb_network_header(frag) + hlen);
+ frag->transport_header = (frag->network_header + hlen +
+ sizeof(struct frag_hdr));
+
+ /*
+ * Charge the memory for the fragment to any owner
+ * it might possess
+ */
+ if (skb->sk)
+ skb_set_owner_w(frag, skb->sk);
+
+ /*
+ * Copy the packet header into the new buffer.
+ */
+ skb_copy_from_linear_data(skb, skb_network_header(frag), hlen);
+
+ /*
+ * Build fragment header.
+ */
+ fh->nexthdr = nexthdr;
+ fh->reserved = 0;
+ if (!frag_id) {
+ ipv6_select_ident(fh, rt);
+ frag_id = fh->identification;
+ } else
+ fh->identification = frag_id;
+
+ /*
+ * Copy a block of the IP datagram.
+ */
+ if (skb_copy_bits(skb, ptr, skb_transport_header(frag), len))
+ BUG();
+ left -= len;
+
+ fh->frag_off = htons(offset);
+ if (left > 0)
+ fh->frag_off |= htons(IP6_MF);
+ ipv6_hdr(frag)->payload_len = htons(frag->len -
+ sizeof(struct ipv6hdr));
+
+ ptr += len;
+ offset += len;
+
+ /*
+ * Put this fragment into the sending queue.
+ */
+ err = output(frag);
+ if (err)
+ goto fail;
+
+ IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_FRAGCREATES);
+ }
+ IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_FRAGOKS);
+ kfree_skb(skb);
+ return err;
+
+fail:
+ IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_FRAGFAILS);
+ kfree_skb(skb);
+ return err;
+}
+
+static inline int ip6_rt_check(const struct rt6key *rt_key,
+ const struct in6_addr *fl_addr,
+ const struct in6_addr *addr_cache)
+{
+ return (rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) &&
+ (addr_cache == NULL || !ipv6_addr_equal(fl_addr, addr_cache));
+}
+
+static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
+ struct dst_entry *dst,
+ const struct flowi6 *fl6)
+{
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct rt6_info *rt;
+
+ if (!dst)
+ goto out;
+
+ if (dst->ops->family != AF_INET6) {
+ dst_release(dst);
+ return NULL;
+ }
+
+ rt = (struct rt6_info *)dst;
+ /* Yes, checking route validity in not connected
+ * case is not very simple. Take into account,
+ * that we do not support routing by source, TOS,
+ * and MSG_DONTROUTE --ANK (980726)
+ *
+ * 1. ip6_rt_check(): If route was host route,
+ * check that cached destination is current.
+ * If it is network route, we still may
+ * check its validity using saved pointer
+ * to the last used address: daddr_cache.
+ * We do not want to save whole address now,
+ * (because main consumer of this service
+ * is tcp, which has not this problem),
+ * so that the last trick works only on connected
+ * sockets.
+ * 2. oif also should be the same.
+ */
+ if (ip6_rt_check(&rt->rt6i_dst, &fl6->daddr, np->daddr_cache) ||
+#ifdef CONFIG_IPV6_SUBTREES
+ ip6_rt_check(&rt->rt6i_src, &fl6->saddr, np->saddr_cache) ||
+#endif
+ (fl6->flowi6_oif && fl6->flowi6_oif != dst->dev->ifindex)) {
+ dst_release(dst);
+ dst = NULL;
+ }
+
+out:
+ return dst;
+}
+
+static int ip6_dst_lookup_tail(struct sock *sk,
+ struct dst_entry **dst, struct flowi6 *fl6)
+{
+ struct net *net = sock_net(sk);
+#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
+ struct neighbour *n;
+#endif
+ int err;
+
+ if (*dst == NULL)
+ *dst = ip6_route_output(net, sk, fl6);
+
+ if ((err = (*dst)->error))
+ goto out_err_release;
+
+ if (ipv6_addr_any(&fl6->saddr)) {
+ struct rt6_info *rt = (struct rt6_info *) *dst;
+ err = ip6_route_get_saddr(net, rt, &fl6->daddr,
+ sk ? inet6_sk(sk)->srcprefs : 0,
+ &fl6->saddr);
+ if (err)
+ goto out_err_release;
+ }
+
+#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
+ /*
+ * Here if the dst entry we've looked up
+ * has a neighbour entry that is in the INCOMPLETE
+ * state and the src address from the flow is
+ * marked as OPTIMISTIC, we release the found
+ * dst entry and replace it instead with the
+ * dst entry of the nexthop router
+ */
+ rcu_read_lock();
+ n = dst_get_neighbour_noref(*dst);
+ if (n && !(n->nud_state & NUD_VALID)) {
+ struct inet6_ifaddr *ifp;
+ struct flowi6 fl_gw6;
+ int redirect;
+
+ rcu_read_unlock();
+ ifp = ipv6_get_ifaddr(net, &fl6->saddr,
+ (*dst)->dev, 1);
+
+ redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC);
+ if (ifp)
+ in6_ifa_put(ifp);
+
+ if (redirect) {
+ /*
+ * We need to get the dst entry for the
+ * default router instead
+ */
+ dst_release(*dst);
+ memcpy(&fl_gw6, fl6, sizeof(struct flowi6));
+ memset(&fl_gw6.daddr, 0, sizeof(struct in6_addr));
+ *dst = ip6_route_output(net, sk, &fl_gw6);
+ if ((err = (*dst)->error))
+ goto out_err_release;
+ }
+ } else {
+ rcu_read_unlock();
+ }
+#endif
+
+ return 0;
+
+out_err_release:
+ if (err == -ENETUNREACH)
+ IP6_INC_STATS_BH(net, NULL, IPSTATS_MIB_OUTNOROUTES);
+ dst_release(*dst);
+ *dst = NULL;
+ return err;
+}
+
+/**
+ * ip6_dst_lookup - perform route lookup on flow
+ * @sk: socket which provides route info
+ * @dst: pointer to dst_entry * for result
+ * @fl6: flow to lookup
+ *
+ * This function performs a route lookup on the given flow.
+ *
+ * It returns zero on success, or a standard errno code on error.
+ */
+int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi6 *fl6)
+{
+ *dst = NULL;
+ return ip6_dst_lookup_tail(sk, dst, fl6);
+}
+EXPORT_SYMBOL_GPL(ip6_dst_lookup);
+
+/**
+ * ip6_dst_lookup_flow - perform route lookup on flow with ipsec
+ * @sk: socket which provides route info
+ * @fl6: flow to lookup
+ * @final_dst: final destination address for ipsec lookup
+ * @can_sleep: we are in a sleepable context
+ *
+ * This function performs a route lookup on the given flow.
+ *
+ * It returns a valid dst pointer on success, or a pointer encoded
+ * error code.
+ */
+struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
+ const struct in6_addr *final_dst,
+ bool can_sleep)
+{
+ struct dst_entry *dst = NULL;
+ int err;
+
+ err = ip6_dst_lookup_tail(sk, &dst, fl6);
+ if (err)
+ return ERR_PTR(err);
+ if (final_dst)
+ fl6->daddr = *final_dst;
+ if (can_sleep)
+ fl6->flowi6_flags |= FLOWI_FLAG_CAN_SLEEP;
+
+ return xfrm_lookup(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
+}
+EXPORT_SYMBOL_GPL(ip6_dst_lookup_flow);
+
+/**
+ * ip6_sk_dst_lookup_flow - perform socket cached route lookup on flow
+ * @sk: socket which provides the dst cache and route info
+ * @fl6: flow to lookup
+ * @final_dst: final destination address for ipsec lookup
+ * @can_sleep: we are in a sleepable context
+ *
+ * This function performs a route lookup on the given flow with the
+ * possibility of using the cached route in the socket if it is valid.
+ * It will take the socket dst lock when operating on the dst cache.
+ * As a result, this function can only be used in process context.
+ *
+ * It returns a valid dst pointer on success, or a pointer encoded
+ * error code.
+ */
+struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
+ const struct in6_addr *final_dst,
+ bool can_sleep)
+{
+ struct dst_entry *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie);
+ int err;
+
+ dst = ip6_sk_dst_check(sk, dst, fl6);
+
+ err = ip6_dst_lookup_tail(sk, &dst, fl6);
+ if (err)
+ return ERR_PTR(err);
+ if (final_dst)
+ fl6->daddr = *final_dst;
+ if (can_sleep)
+ fl6->flowi6_flags |= FLOWI_FLAG_CAN_SLEEP;
+
+ return xfrm_lookup(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
+}
+EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup_flow);
+
+static inline int ip6_ufo_append_data(struct sock *sk,
+ int getfrag(void *from, char *to, int offset, int len,
+ int odd, struct sk_buff *skb),
+ void *from, int length, int hh_len, int fragheaderlen,
+ int transhdrlen, int mtu,unsigned int flags,
+ struct rt6_info *rt)
+
+{
+ struct sk_buff *skb;
+ int err;
+
+ /* There is support for UDP large send offload by network
+ * device, so create one single skb packet containing complete
+ * udp datagram
+ */
+ if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) {
+ struct frag_hdr fhdr;
+
+ skb = sock_alloc_send_skb(sk,
+ hh_len + fragheaderlen + transhdrlen + 20,
+ (flags & MSG_DONTWAIT), &err);
+ if (skb == NULL)
+ return err;
+
+ /* reserve space for Hardware header */
+ skb_reserve(skb, hh_len);
+
+ /* create space for UDP/IP header */
+ skb_put(skb,fragheaderlen + transhdrlen);
+
+ /* initialize network header pointer */
+ skb_reset_network_header(skb);
+
+ /* initialize protocol header pointer */
+ skb->transport_header = skb->network_header + fragheaderlen;
+
+ skb->ip_summed = CHECKSUM_PARTIAL;
+ skb->csum = 0;
+
+ /* Specify the length of each IPv6 datagram fragment.
+ * It has to be a multiple of 8.
+ */
+ skb_shinfo(skb)->gso_size = (mtu - fragheaderlen -
+ sizeof(struct frag_hdr)) & ~7;
+ skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
+ ipv6_select_ident(&fhdr, rt);
+ skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
+ __skb_queue_tail(&sk->sk_write_queue, skb);
+ }
+
+ return skb_append_datato_frags(sk, skb, getfrag, from,
+ (length - transhdrlen));
+}
+
+static inline struct ipv6_opt_hdr *ip6_opt_dup(struct ipv6_opt_hdr *src,
+ gfp_t gfp)
+{
+ return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL;
+}
+
+static inline struct ipv6_rt_hdr *ip6_rthdr_dup(struct ipv6_rt_hdr *src,
+ gfp_t gfp)
+{
+ return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL;
+}
+
+static void ip6_append_data_mtu(unsigned int *mtu,
+ int *maxfraglen,
+ unsigned int fragheaderlen,
+ struct sk_buff *skb,
+ struct rt6_info *rt,
+ unsigned int orig_mtu)
+{
+ if (!(rt->dst.flags & DST_XFRM_TUNNEL)) {
+ if (skb == NULL) {
+ /* first fragment, reserve header_len */
+ *mtu = orig_mtu - rt->dst.header_len;
+
+ } else {
+ /*
+ * this fragment is not first, the headers
+ * space is regarded as data space.
+ */
+ *mtu = orig_mtu;
+ }
+ *maxfraglen = ((*mtu - fragheaderlen) & ~7)
+ + fragheaderlen - sizeof(struct frag_hdr);
+ }
+}
+
+int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
+ int offset, int len, int odd, struct sk_buff *skb),
+ void *from, int length, int transhdrlen,
+ int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi6 *fl6,
+ struct rt6_info *rt, unsigned int flags, int dontfrag)
+{
+ struct inet_sock *inet = inet_sk(sk);
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct inet_cork *cork;
+ struct sk_buff *skb, *skb_prev = NULL;
+ unsigned int maxfraglen, fragheaderlen, mtu, orig_mtu;
+ int exthdrlen;
+ int dst_exthdrlen;
+ int hh_len;
+ int copy;
+ int err;
+ int offset = 0;
+ int csummode = CHECKSUM_NONE;
+ __u8 tx_flags = 0;
+
+ if (flags&MSG_PROBE)
+ return 0;
+ cork = &inet->cork.base;
+ if (skb_queue_empty(&sk->sk_write_queue)) {
+ /*
+ * setup for corking
+ */
+ if (opt) {
+ if (WARN_ON(np->cork.opt))
+ return -EINVAL;
+
+ np->cork.opt = kzalloc(opt->tot_len, sk->sk_allocation);
+ if (unlikely(np->cork.opt == NULL))
+ return -ENOBUFS;
+
+ np->cork.opt->tot_len = opt->tot_len;
+ np->cork.opt->opt_flen = opt->opt_flen;
+ np->cork.opt->opt_nflen = opt->opt_nflen;
+
+ np->cork.opt->dst0opt = ip6_opt_dup(opt->dst0opt,
+ sk->sk_allocation);
+ if (opt->dst0opt && !np->cork.opt->dst0opt)
+ return -ENOBUFS;
+
+ np->cork.opt->dst1opt = ip6_opt_dup(opt->dst1opt,
+ sk->sk_allocation);
+ if (opt->dst1opt && !np->cork.opt->dst1opt)
+ return -ENOBUFS;
+
+ np->cork.opt->hopopt = ip6_opt_dup(opt->hopopt,
+ sk->sk_allocation);
+ if (opt->hopopt && !np->cork.opt->hopopt)
+ return -ENOBUFS;
+
+ np->cork.opt->srcrt = ip6_rthdr_dup(opt->srcrt,
+ sk->sk_allocation);
+ if (opt->srcrt && !np->cork.opt->srcrt)
+ return -ENOBUFS;
+
+ /* need source address above miyazawa*/
+ }
+ dst_hold(&rt->dst);
+ cork->dst = &rt->dst;
+ inet->cork.fl.u.ip6 = *fl6;
+ np->cork.hop_limit = hlimit;
+ np->cork.tclass = tclass;
+ if (rt->dst.flags & DST_XFRM_TUNNEL)
+ mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ?
+ rt->dst.dev->mtu : dst_mtu(&rt->dst);
+ else
+ mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ?
+ rt->dst.dev->mtu : dst_mtu(rt->dst.path);
+ if (np->frag_size < mtu) {
+ if (np->frag_size)
+ mtu = np->frag_size;
+ }
+ cork->fragsize = mtu;
+ if (dst_allfrag(rt->dst.path))
+ cork->flags |= IPCORK_ALLFRAG;
+ cork->length = 0;
+ sk->sk_sndmsg_page = NULL;
+ sk->sk_sndmsg_off = 0;
+ exthdrlen = (opt ? opt->opt_flen : 0);
+ length += exthdrlen;
+ transhdrlen += exthdrlen;
+ dst_exthdrlen = rt->dst.header_len - rt->rt6i_nfheader_len;
+ } else {
+ rt = (struct rt6_info *)cork->dst;
+ fl6 = &inet->cork.fl.u.ip6;
+ opt = np->cork.opt;
+ transhdrlen = 0;
+ exthdrlen = 0;
+ dst_exthdrlen = 0;
+ mtu = cork->fragsize;
+ }
+ orig_mtu = mtu;
+
+ hh_len = LL_RESERVED_SPACE(rt->dst.dev);
+
+ fragheaderlen = sizeof(struct ipv6hdr) + rt->rt6i_nfheader_len +
+ (opt ? opt->opt_nflen : 0);
+ maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr);
+
+ if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) {
+ if (cork->length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) {
+ ipv6_local_error(sk, EMSGSIZE, fl6, mtu-exthdrlen);
+ return -EMSGSIZE;
+ }
+ }
+
+ /* For UDP, check if TX timestamp is enabled */
+ if (sk->sk_type == SOCK_DGRAM) {
+ err = sock_tx_timestamp(sk, &tx_flags);
+ if (err)
+ goto error;
+ }
+
+ /*
+ * Let's try using as much space as possible.
+ * Use MTU if total length of the message fits into the MTU.
+ * Otherwise, we need to reserve fragment header and
+ * fragment alignment (= 8-15 octects, in total).
+ *
+ * Note that we may need to "move" the data from the tail of
+ * of the buffer to the new fragment when we split
+ * the message.
+ *
+ * FIXME: It may be fragmented into multiple chunks
+ * at once if non-fragmentable extension headers
+ * are too large.
+ * --yoshfuji
+ */
+
+ if ((length > mtu) && dontfrag && (sk->sk_protocol == IPPROTO_UDP ||
+ sk->sk_protocol == IPPROTO_RAW)) {
+ ipv6_local_rxpmtu(sk, fl6, mtu-exthdrlen);
+ return -EMSGSIZE;
+ }
+
+ skb = skb_peek_tail(&sk->sk_write_queue);
+ cork->length += length;
+/*
+ if (((length > mtu) ||
+ (skb && skb_has_frags(skb))) &&
+ (sk->sk_protocol == IPPROTO_UDP) &&
+ (rt->dst.dev->features & NETIF_F_UFO)) {
+*/
+ if ((skb && skb_is_gso(skb)) ||//CVE-2017-1000112
+ (((length > mtu) ||
+ (skb && skb_has_frags(skb))) &&
+ (sk->sk_protocol == IPPROTO_UDP) &&
+ (rt->dst.dev->features & NETIF_F_UFO))) {
+ err = ip6_ufo_append_data(sk, getfrag, from, length,
+ hh_len, fragheaderlen,
+ transhdrlen, mtu, flags, rt);
+ if (err)
+ goto error;
+ return 0;
+ }
+
+ if (!skb)
+ goto alloc_new_skb;
+
+ while (length > 0) {
+ /* Check if the remaining data fits into current packet. */
+ copy = (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len;
+ if (copy < length)
+ copy = maxfraglen - skb->len;
+
+ if (copy <= 0) {
+ char *data;
+ unsigned int datalen;
+ unsigned int fraglen;
+ unsigned int fraggap;
+ unsigned int alloclen;
+alloc_new_skb:
+ /* There's no room in the current skb */
+ if (skb)
+ fraggap = skb->len - maxfraglen;
+ else
+ fraggap = 0;
+ /* update mtu and maxfraglen if necessary */
+ if (skb == NULL || skb_prev == NULL)
+ ip6_append_data_mtu(&mtu, &maxfraglen,
+ fragheaderlen, skb, rt,
+ orig_mtu);
+
+ skb_prev = skb;
+
+ /*
+ * If remaining data exceeds the mtu,
+ * we know we need more fragment(s).
+ */
+ datalen = length + fraggap;
+
+ if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
+ datalen = maxfraglen - fragheaderlen - rt->dst.trailer_len;
+ if ((flags & MSG_MORE) &&
+ !(rt->dst.dev->features&NETIF_F_SG))
+ alloclen = mtu;
+ else
+ alloclen = datalen + fragheaderlen;
+
+ alloclen += dst_exthdrlen;
+
+ if (datalen != length + fraggap) {
+ /*
+ * this is not the last fragment, the trailer
+ * space is regarded as data space.
+ */
+ datalen += rt->dst.trailer_len;
+ }
+
+ alloclen += rt->dst.trailer_len;
+ fraglen = datalen + fragheaderlen;
+
+ /*
+ * We just reserve space for fragment header.
+ * Note: this may be overallocation if the message
+ * (without MSG_MORE) fits into the MTU.
+ */
+ alloclen += sizeof(struct frag_hdr);
+
+ if (transhdrlen) {
+ skb = sock_alloc_send_skb(sk,
+ alloclen + hh_len,
+ (flags & MSG_DONTWAIT), &err);
+ } else {
+ skb = NULL;
+ if (atomic_read(&sk->sk_wmem_alloc) <=
+ 2 * sk->sk_sndbuf)
+ skb = sock_wmalloc(sk,
+ alloclen + hh_len, 1,
+ sk->sk_allocation);
+ if (unlikely(skb == NULL))
+ err = -ENOBUFS;
+ else {
+ /* Only the initial fragment
+ * is time stamped.
+ */
+ tx_flags = 0;
+ }
+ }
+ if (skb == NULL)
+ goto error;
+ /*
+ * Fill in the control structures
+ */
+ skb->ip_summed = csummode;
+ skb->csum = 0;
+ /* reserve for fragmentation and ipsec header */
+ skb_reserve(skb, hh_len + sizeof(struct frag_hdr) +
+ dst_exthdrlen);
+
+ if (sk->sk_type == SOCK_DGRAM)
+ skb_shinfo(skb)->tx_flags = tx_flags;
+
+ /*
+ * Find where to start putting bytes
+ */
+ data = skb_put(skb, fraglen);
+ skb_set_network_header(skb, exthdrlen);
+ data += fragheaderlen;
+ skb->transport_header = (skb->network_header +
+ fragheaderlen);
+ if (fraggap) {
+ skb->csum = skb_copy_and_csum_bits(
+ skb_prev, maxfraglen,
+ data + transhdrlen, fraggap, 0);
+ skb_prev->csum = csum_sub(skb_prev->csum,
+ skb->csum);
+ data += fraggap;
+ pskb_trim_unique(skb_prev, maxfraglen);
+ }
+ copy = datalen - transhdrlen - fraggap;
+
+ if (copy < 0) {
+ err = -EINVAL;
+ kfree_skb(skb);
+ goto error;
+ } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) {
+ err = -EFAULT;
+ kfree_skb(skb);
+ goto error;
+ }
+
+ offset += copy;
+ length -= datalen - fraggap;
+ transhdrlen = 0;
+ exthdrlen = 0;
+ dst_exthdrlen = 0;
+ csummode = CHECKSUM_NONE;
+
+ /*
+ * Put the packet on the pending queue
+ */
+ __skb_queue_tail(&sk->sk_write_queue, skb);
+ continue;
+ }
+
+ if (copy > length)
+ copy = length;
+
+ if (!(rt->dst.dev->features&NETIF_F_SG)) {
+ unsigned int off;
+
+ off = skb->len;
+ if (getfrag(from, skb_put(skb, copy),
+ offset, copy, off, skb) < 0) {
+ __skb_trim(skb, off);
+ err = -EFAULT;
+ goto error;
+ }
+ } else {
+ int i = skb_shinfo(skb)->nr_frags;
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1];
+ struct page *page = sk->sk_sndmsg_page;
+ int off = sk->sk_sndmsg_off;
+ unsigned int left;
+
+ if (page && (left = PAGE_SIZE - off) > 0) {
+ if (copy >= left)
+ copy = left;
+ if (page != skb_frag_page(frag)) {
+ if (i == MAX_SKB_FRAGS) {
+ err = -EMSGSIZE;
+ goto error;
+ }
+ skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0);
+ skb_frag_ref(skb, i);
+ frag = &skb_shinfo(skb)->frags[i];
+ }
+ } else if(i < MAX_SKB_FRAGS) {
+ if (copy > PAGE_SIZE)
+ copy = PAGE_SIZE;
+ page = alloc_pages(sk->sk_allocation, 0);
+ if (page == NULL) {
+ err = -ENOMEM;
+ goto error;
+ }
+ netslab_inc(IP6_OUTPUT_ALLOC_PAGES);
+ sk->sk_sndmsg_page = page;
+ sk->sk_sndmsg_off = 0;
+
+ skb_fill_page_desc(skb, i, page, 0, 0);
+ frag = &skb_shinfo(skb)->frags[i];
+ } else {
+ err = -EMSGSIZE;
+ goto error;
+ }
+ if (getfrag(from,
+ skb_frag_address(frag) + skb_frag_size(frag),
+ offset, copy, skb->len, skb) < 0) {
+ err = -EFAULT;
+ goto error;
+ }
+ sk->sk_sndmsg_off += copy;
+ skb_frag_size_add(frag, copy);
+ skb->len += copy;
+ skb->data_len += copy;
+ skb->truesize += copy;
+ atomic_add(copy, &sk->sk_wmem_alloc);
+ }
+ offset += copy;
+ length -= copy;
+ }
+ return 0;
+error:
+ cork->length -= length;
+ IP6_INC_STATS(sock_net(sk), rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
+ return err;
+}
+
+extern int fast_local6_output_num;
+static void ip6_cork_release(struct inet_sock *inet, struct ipv6_pinfo *np)
+{
+ if (np->cork.opt) {
+ kfree(np->cork.opt->dst0opt);
+ kfree(np->cork.opt->dst1opt);
+ kfree(np->cork.opt->hopopt);
+ kfree(np->cork.opt->srcrt);
+ kfree(np->cork.opt);
+ np->cork.opt = NULL;
+ }
+
+ if (inet->cork.base.dst) {
+ dst_release(inet->cork.base.dst);
+ inet->cork.base.dst = NULL;
+ inet->cork.base.flags &= ~IPCORK_ALLFRAG;
+ }
+ memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
+}
+
+int ip6_push_pending_frames(struct sock *sk)
+{
+ struct sk_buff *skb, *tmp_skb;
+ struct sk_buff **tail_skb;
+ struct in6_addr final_dst_buf, *final_dst = &final_dst_buf;
+ struct inet_sock *inet = inet_sk(sk);
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct net *net = sock_net(sk);
+ struct ipv6hdr *hdr;
+ struct ipv6_txoptions *opt = np->cork.opt;
+ struct rt6_info *rt = (struct rt6_info *)inet->cork.base.dst;
+ struct flowi6 *fl6 = &inet->cork.fl.u.ip6;
+ unsigned char proto = fl6->flowi6_proto;
+ int err = 0;
+
+ if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL)
+ goto out;
+ tail_skb = &(skb_shinfo(skb)->frag_list);
+
+ /* move skb->data to ip header from ext header */
+ if (skb->data < skb_network_header(skb))
+ __skb_pull(skb, skb_network_offset(skb));
+ while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) {
+ __skb_pull(tmp_skb, skb_network_header_len(skb));
+ *tail_skb = tmp_skb;
+ tail_skb = &(tmp_skb->next);
+ skb->len += tmp_skb->len;
+ skb->data_len += tmp_skb->len;
+ skb->truesize += tmp_skb->truesize;
+ tmp_skb->destructor = NULL;
+ tmp_skb->sk = NULL;
+ }
+
+ /* Allow local fragmentation. */
+ if (np->pmtudisc < IPV6_PMTUDISC_DO)
+ skb->local_df = 1;
+
+ *final_dst = fl6->daddr;
+ __skb_pull(skb, skb_network_header_len(skb));
+ if (opt && opt->opt_flen)
+ ipv6_push_frag_opts(skb, opt, &proto);
+ if (opt && opt->opt_nflen)
+ ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst);
+
+ skb_push(skb, sizeof(struct ipv6hdr));
+ skb_reset_network_header(skb);
+ hdr = ipv6_hdr(skb);
+
+ *(__be32*)hdr = fl6->flowlabel |
+ htonl(0x60000000 | ((int)np->cork.tclass << 20));
+
+ hdr->hop_limit = np->cork.hop_limit;
+ hdr->nexthdr = proto;
+ hdr->saddr = fl6->saddr;
+ hdr->daddr = *final_dst;
+
+ skb->priority = sk->sk_priority;
+ skb->mark = sk->sk_mark;
+
+ skb_dst_set(skb, dst_clone(&rt->dst));
+ IP6_UPD_PO_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUT, skb->len);
+ if (proto == IPPROTO_ICMPV6) {
+ struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
+
+ ICMP6MSGOUT_INC_STATS(net, idev, icmp6_hdr(skb)->icmp6_type);
+ ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
+ }
+
+ //Èç¹ûÒѾ·¢Ëͳ¬¹ýãÐÖµÁË£¬Ö±½Ó¿ìËÙÌí¼ÓMACÍ·£¬Ìø¹ýËùÓеÄIP²ãHOOK¹³×Óº¯Êý
+ if (fast_local6_output_proc && fast_local6_output_proc(skb))
+ {
+ fast_local6_output_num++;
+ err = ip6_finish_output(skb);
+ } else {
+ err = ip6_local_out(skb);
+ }
+ if (err) {
+ if (err > 0)
+ err = net_xmit_errno(err);
+ if (err)
+ goto error;
+ }
+
+out:
+ ip6_cork_release(inet, np);
+ return err;
+error:
+ IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
+ goto out;
+}
+
+void ip6_flush_pending_frames(struct sock *sk)
+{
+ struct sk_buff *skb;
+
+ while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) {
+ if (skb_dst(skb))
+ IP6_INC_STATS(sock_net(sk), ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_OUTDISCARDS);
+ kfree_skb(skb);
+ }
+
+ ip6_cork_release(inet_sk(sk), inet6_sk(sk));
+}