mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-22 17:01:14 +00:00
1546 lines
38 KiB
C
1546 lines
38 KiB
C
/*
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* IPv6 output functions
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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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*
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* Based on linux/net/ipv4/ip_output.c
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Changes:
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* A.N.Kuznetsov : airthmetics in fragmentation.
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* extension headers are implemented.
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* route changes now work.
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* ip6_forward does not confuse sniffers.
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* etc.
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*
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* H. von Brand : Added missing #include <linux/string.h>
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* Imran Patel : frag id should be in NBO
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* Kazunori MIYAZAWA @USAGI
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* : add ip6_append_data and related functions
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* for datagram xmit
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*/
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#include <linux/errno.h>
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#include <linux/kernel.h>
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#include <linux/string.h>
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#include <linux/socket.h>
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#include <linux/net.h>
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#include <linux/netdevice.h>
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#include <linux/if_arp.h>
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#include <linux/in6.h>
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#include <linux/tcp.h>
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#include <linux/route.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/netfilter.h>
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#include <linux/netfilter_ipv6.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/ndisc.h>
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#include <net/protocol.h>
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#include <net/ip6_route.h>
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#include <net/addrconf.h>
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#include <net/rawv6.h>
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#include <net/icmp.h>
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#include <net/xfrm.h>
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#include <net/checksum.h>
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#include <linux/mroute6.h>
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static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
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int __ip6_local_out(struct sk_buff *skb)
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{
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int len;
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len = skb->len - sizeof(struct ipv6hdr);
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if (len > IPV6_MAXPLEN)
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len = 0;
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ipv6_hdr(skb)->payload_len = htons(len);
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return nf_hook(PF_INET6, NF_INET_LOCAL_OUT, skb, NULL, skb_dst(skb)->dev,
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dst_output);
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}
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int ip6_local_out(struct sk_buff *skb)
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{
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int err;
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err = __ip6_local_out(skb);
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if (likely(err == 1))
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err = dst_output(skb);
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return err;
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}
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EXPORT_SYMBOL_GPL(ip6_local_out);
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static int ip6_output_finish(struct sk_buff *skb)
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{
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struct dst_entry *dst = skb_dst(skb);
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if (dst->hh)
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return neigh_hh_output(dst->hh, skb);
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else if (dst->neighbour)
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return dst->neighbour->output(skb);
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IP6_INC_STATS_BH(dev_net(dst->dev),
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ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
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kfree_skb(skb);
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return -EINVAL;
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}
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/* dev_loopback_xmit for use with netfilter. */
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static int ip6_dev_loopback_xmit(struct sk_buff *newskb)
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{
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skb_reset_mac_header(newskb);
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__skb_pull(newskb, skb_network_offset(newskb));
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newskb->pkt_type = PACKET_LOOPBACK;
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newskb->ip_summed = CHECKSUM_UNNECESSARY;
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WARN_ON(!skb_dst(newskb));
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netif_rx_ni(newskb);
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return 0;
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}
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static int ip6_output2(struct sk_buff *skb)
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{
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struct dst_entry *dst = skb_dst(skb);
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struct net_device *dev = dst->dev;
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skb->protocol = htons(ETH_P_IPV6);
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skb->dev = dev;
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if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
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struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
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if (!(dev->flags & IFF_LOOPBACK) && sk_mc_loop(skb->sk) &&
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((mroute6_socket(dev_net(dev)) &&
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!(IP6CB(skb)->flags & IP6SKB_FORWARDED)) ||
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ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr,
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&ipv6_hdr(skb)->saddr))) {
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struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
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/* Do not check for IFF_ALLMULTI; multicast routing
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is not supported in any case.
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*/
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if (newskb)
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NF_HOOK(PF_INET6, NF_INET_POST_ROUTING, newskb,
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NULL, newskb->dev,
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ip6_dev_loopback_xmit);
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if (ipv6_hdr(skb)->hop_limit == 0) {
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IP6_INC_STATS(dev_net(dev), idev,
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IPSTATS_MIB_OUTDISCARDS);
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kfree_skb(skb);
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return 0;
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}
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}
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IP6_UPD_PO_STATS(dev_net(dev), idev, IPSTATS_MIB_OUTMCAST,
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skb->len);
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}
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return NF_HOOK(PF_INET6, NF_INET_POST_ROUTING, skb, NULL, skb->dev,
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ip6_output_finish);
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}
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static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
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{
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struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
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return (np && np->pmtudisc == IPV6_PMTUDISC_PROBE) ?
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skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
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}
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int ip6_output(struct sk_buff *skb)
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{
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struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
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if (unlikely(idev->cnf.disable_ipv6)) {
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IP6_INC_STATS(dev_net(skb_dst(skb)->dev), idev,
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IPSTATS_MIB_OUTDISCARDS);
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kfree_skb(skb);
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return 0;
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}
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if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
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dst_allfrag(skb_dst(skb)))
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return ip6_fragment(skb, ip6_output2);
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else
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return ip6_output2(skb);
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}
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/*
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* xmit an sk_buff (used by TCP, SCTP and DCCP)
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*/
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int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
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struct ipv6_txoptions *opt)
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{
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struct net *net = sock_net(sk);
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struct ipv6_pinfo *np = inet6_sk(sk);
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struct in6_addr *first_hop = &fl->fl6_dst;
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struct dst_entry *dst = skb_dst(skb);
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struct ipv6hdr *hdr;
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u8 proto = fl->proto;
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int seg_len = skb->len;
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int hlimit = -1;
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int tclass = 0;
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u32 mtu;
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if (opt) {
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unsigned int head_room;
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/* First: exthdrs may take lots of space (~8K for now)
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MAX_HEADER is not enough.
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*/
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head_room = opt->opt_nflen + opt->opt_flen;
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seg_len += head_room;
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head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev);
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if (skb_headroom(skb) < head_room) {
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struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room);
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if (skb2 == NULL) {
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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 -ENOBUFS;
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}
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kfree_skb(skb);
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skb = skb2;
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if (sk)
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skb_set_owner_w(skb, sk);
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}
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if (opt->opt_flen)
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ipv6_push_frag_opts(skb, opt, &proto);
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if (opt->opt_nflen)
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ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop);
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}
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skb_push(skb, sizeof(struct ipv6hdr));
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skb_reset_network_header(skb);
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hdr = ipv6_hdr(skb);
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/*
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* Fill in the IPv6 header
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*/
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if (np) {
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tclass = np->tclass;
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hlimit = np->hop_limit;
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}
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if (hlimit < 0)
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hlimit = ip6_dst_hoplimit(dst);
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*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | fl->fl6_flowlabel;
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hdr->payload_len = htons(seg_len);
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hdr->nexthdr = proto;
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hdr->hop_limit = hlimit;
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ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
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ipv6_addr_copy(&hdr->daddr, first_hop);
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skb->priority = sk->sk_priority;
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skb->mark = sk->sk_mark;
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mtu = dst_mtu(dst);
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if ((skb->len <= mtu) || skb->local_df || skb_is_gso(skb)) {
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IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)),
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IPSTATS_MIB_OUT, skb->len);
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return NF_HOOK(PF_INET6, NF_INET_LOCAL_OUT, skb, NULL, dst->dev,
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dst_output);
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}
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if (net_ratelimit())
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printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n");
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skb->dev = dst->dev;
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icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
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IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS);
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kfree_skb(skb);
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return -EMSGSIZE;
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}
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EXPORT_SYMBOL(ip6_xmit);
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/*
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* To avoid extra problems ND packets are send through this
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* routine. It's code duplication but I really want to avoid
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* extra checks since ipv6_build_header is used by TCP (which
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* is for us performance critical)
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*/
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int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev,
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const struct in6_addr *saddr, const struct in6_addr *daddr,
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int proto, int len)
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{
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struct ipv6_pinfo *np = inet6_sk(sk);
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struct ipv6hdr *hdr;
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int totlen;
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skb->protocol = htons(ETH_P_IPV6);
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skb->dev = dev;
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totlen = len + sizeof(struct ipv6hdr);
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skb_reset_network_header(skb);
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skb_put(skb, sizeof(struct ipv6hdr));
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hdr = ipv6_hdr(skb);
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*(__be32*)hdr = htonl(0x60000000);
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hdr->payload_len = htons(len);
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hdr->nexthdr = proto;
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hdr->hop_limit = np->hop_limit;
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ipv6_addr_copy(&hdr->saddr, saddr);
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ipv6_addr_copy(&hdr->daddr, daddr);
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return 0;
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}
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static int ip6_call_ra_chain(struct sk_buff *skb, int sel)
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{
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struct ip6_ra_chain *ra;
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struct sock *last = NULL;
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read_lock(&ip6_ra_lock);
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for (ra = ip6_ra_chain; ra; ra = ra->next) {
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struct sock *sk = ra->sk;
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if (sk && ra->sel == sel &&
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(!sk->sk_bound_dev_if ||
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sk->sk_bound_dev_if == skb->dev->ifindex)) {
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if (last) {
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struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
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if (skb2)
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rawv6_rcv(last, skb2);
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}
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last = sk;
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}
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}
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if (last) {
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rawv6_rcv(last, skb);
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read_unlock(&ip6_ra_lock);
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return 1;
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}
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read_unlock(&ip6_ra_lock);
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return 0;
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}
|
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static int ip6_forward_proxy_check(struct sk_buff *skb)
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{
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struct ipv6hdr *hdr = ipv6_hdr(skb);
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u8 nexthdr = hdr->nexthdr;
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int offset;
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|
|
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if (ipv6_ext_hdr(nexthdr)) {
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offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr);
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if (offset < 0)
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return 0;
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} else
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offset = sizeof(struct ipv6hdr);
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if (nexthdr == IPPROTO_ICMPV6) {
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struct icmp6hdr *icmp6;
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if (!pskb_may_pull(skb, (skb_network_header(skb) +
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offset + 1 - skb->data)))
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return 0;
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icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
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switch (icmp6->icmp6_type) {
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case NDISC_ROUTER_SOLICITATION:
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case NDISC_ROUTER_ADVERTISEMENT:
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case NDISC_NEIGHBOUR_SOLICITATION:
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case NDISC_NEIGHBOUR_ADVERTISEMENT:
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case NDISC_REDIRECT:
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/* For reaction involving unicast neighbor discovery
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* message destined to the proxied address, pass it to
|
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* input function.
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*/
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return 1;
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default:
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break;
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}
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}
|
|
|
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/*
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* The proxying router can't forward traffic sent to a link-local
|
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* address, so signal the sender and discard the packet. This
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* behavior is clarified by the MIPv6 specification.
|
|
*/
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if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) {
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dst_link_failure(skb);
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return -1;
|
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}
|
|
|
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return 0;
|
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}
|
|
|
|
static inline int ip6_forward_finish(struct sk_buff *skb)
|
|
{
|
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return dst_output(skb);
|
|
}
|
|
|
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int ip6_forward(struct sk_buff *skb)
|
|
{
|
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struct dst_entry *dst = skb_dst(skb);
|
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struct ipv6hdr *hdr = ipv6_hdr(skb);
|
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struct inet6_skb_parm *opt = IP6CB(skb);
|
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struct net *net = dev_net(dst->dev);
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u32 mtu;
|
|
|
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if (net->ipv6.devconf_all->forwarding == 0)
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goto error;
|
|
|
|
if (skb_warn_if_lro(skb))
|
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goto drop;
|
|
|
|
if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
|
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IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
|
|
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) {
|
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u8 *ptr = skb_network_header(skb) + opt->ra;
|
|
if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3]))
|
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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 && dst->neighbour && opt->srcrt == 0 &&
|
|
!skb_sec_path(skb)) {
|
|
struct in6_addr *target = NULL;
|
|
struct rt6_info *rt;
|
|
struct neighbour *n = dst->neighbour;
|
|
|
|
/*
|
|
* incoming and outgoing devices are the same
|
|
* send a redirect.
|
|
*/
|
|
|
|
rt = (struct rt6_info *) dst;
|
|
if ((rt->rt6i_flags & RTF_GATEWAY))
|
|
target = (struct in6_addr*)&n->primary_key;
|
|
else
|
|
target = &hdr->daddr;
|
|
|
|
/* Limit redirects both by destination (here)
|
|
and by source (inside ndisc_send_redirect)
|
|
*/
|
|
if (xrlim_allow(dst, 1*HZ))
|
|
ndisc_send_redirect(skb, n, 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) {
|
|
/* 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(PF_INET6, 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 =
|
|
(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) {
|
|
|
|
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);
|
|
*nexthdr = &exthdr->nexthdr;
|
|
exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) +
|
|
offset);
|
|
}
|
|
|
|
return offset;
|
|
}
|
|
|
|
static 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;
|
|
__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);
|
|
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_frags(skb)) {
|
|
int first_len = skb_pagelen(skb);
|
|
int truesizes = 0;
|
|
|
|
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;
|
|
|
|
/* Partially cloned skb? */
|
|
if (skb_shared(frag))
|
|
goto slow_path;
|
|
|
|
BUG_ON(frag->sk);
|
|
if (skb->sk) {
|
|
frag->sk = skb->sk;
|
|
frag->destructor = sock_wfree;
|
|
truesizes += 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);
|
|
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->truesize -= truesizes;
|
|
skb->len = first_len;
|
|
ipv6_hdr(skb)->payload_len = htons(first_len -
|
|
sizeof(struct ipv6hdr));
|
|
|
|
dst_hold(&rt->u.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->u.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->u.dst),
|
|
IPSTATS_MIB_FRAGOKS);
|
|
dst_release(&rt->u.dst);
|
|
return 0;
|
|
}
|
|
|
|
while (frag) {
|
|
skb = frag->next;
|
|
kfree_skb(frag);
|
|
frag = skb;
|
|
}
|
|
|
|
IP6_INC_STATS(net, ip6_dst_idev(&rt->u.dst),
|
|
IPSTATS_MIB_FRAGFAILS);
|
|
dst_release(&rt->u.dst);
|
|
return err;
|
|
}
|
|
|
|
slow_path:
|
|
left = skb->len - hlen; /* Space per frame */
|
|
ptr = hlen; /* Where to start from */
|
|
|
|
/*
|
|
* Fragment the datagram.
|
|
*/
|
|
|
|
*prevhdr = NEXTHDR_FRAGMENT;
|
|
|
|
/*
|
|
* 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 upto 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)+LL_ALLOCATED_SPACE(rt->u.dst.dev), 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, LL_RESERVED_SPACE(rt->u.dst.dev));
|
|
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);
|
|
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(struct rt6key *rt_key,
|
|
struct in6_addr *fl_addr,
|
|
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,
|
|
struct flowi *fl)
|
|
{
|
|
struct ipv6_pinfo *np = inet6_sk(sk);
|
|
struct rt6_info *rt = (struct rt6_info *)dst;
|
|
|
|
if (!dst)
|
|
goto out;
|
|
|
|
/* 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, &fl->fl6_dst, np->daddr_cache) ||
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
ip6_rt_check(&rt->rt6i_src, &fl->fl6_src, np->saddr_cache) ||
|
|
#endif
|
|
(fl->oif && fl->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 flowi *fl)
|
|
{
|
|
int err;
|
|
struct net *net = sock_net(sk);
|
|
|
|
if (*dst == NULL)
|
|
*dst = ip6_route_output(net, sk, fl);
|
|
|
|
if ((err = (*dst)->error))
|
|
goto out_err_release;
|
|
|
|
if (ipv6_addr_any(&fl->fl6_src)) {
|
|
err = ipv6_dev_get_saddr(net, ip6_dst_idev(*dst)->dev,
|
|
&fl->fl6_dst,
|
|
sk ? inet6_sk(sk)->srcprefs : 0,
|
|
&fl->fl6_src);
|
|
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
|
|
*/
|
|
if ((*dst)->neighbour && !((*dst)->neighbour->nud_state & NUD_VALID)) {
|
|
struct inet6_ifaddr *ifp;
|
|
struct flowi fl_gw;
|
|
int redirect;
|
|
|
|
ifp = ipv6_get_ifaddr(net, &fl->fl6_src,
|
|
(*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_gw, fl, sizeof(struct flowi));
|
|
memset(&fl_gw.fl6_dst, 0, sizeof(struct in6_addr));
|
|
*dst = ip6_route_output(net, sk, &fl_gw);
|
|
if ((err = (*dst)->error))
|
|
goto out_err_release;
|
|
}
|
|
}
|
|
#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
|
|
* @fl: 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 flowi *fl)
|
|
{
|
|
*dst = NULL;
|
|
return ip6_dst_lookup_tail(sk, dst, fl);
|
|
}
|
|
EXPORT_SYMBOL_GPL(ip6_dst_lookup);
|
|
|
|
/**
|
|
* ip6_sk_dst_lookup - perform socket cached route lookup on flow
|
|
* @sk: socket which provides the dst cache and route info
|
|
* @dst: pointer to dst_entry * for result
|
|
* @fl: flow to lookup
|
|
*
|
|
* 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 zero on success, or a standard errno code on error.
|
|
*/
|
|
int ip6_sk_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl)
|
|
{
|
|
*dst = NULL;
|
|
if (sk) {
|
|
*dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie);
|
|
*dst = ip6_sk_dst_check(sk, *dst, fl);
|
|
}
|
|
|
|
return ip6_dst_lookup_tail(sk, dst, fl);
|
|
}
|
|
EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup);
|
|
|
|
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 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) {
|
|
skb = sock_alloc_send_skb(sk,
|
|
hh_len + fragheaderlen + transhdrlen + 20,
|
|
(flags & MSG_DONTWAIT), &err);
|
|
if (skb == NULL)
|
|
return -ENOMEM;
|
|
|
|
/* 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;
|
|
sk->sk_sndmsg_off = 0;
|
|
}
|
|
|
|
err = skb_append_datato_frags(sk,skb, getfrag, from,
|
|
(length - transhdrlen));
|
|
if (!err) {
|
|
struct frag_hdr fhdr;
|
|
|
|
/* 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);
|
|
skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
|
|
__skb_queue_tail(&sk->sk_write_queue, skb);
|
|
|
|
return 0;
|
|
}
|
|
/* There is not enough support do UPD LSO,
|
|
* so follow normal path
|
|
*/
|
|
kfree_skb(skb);
|
|
|
|
return err;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
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 flowi *fl,
|
|
struct rt6_info *rt, unsigned int flags, int dontfrag)
|
|
{
|
|
struct inet_sock *inet = inet_sk(sk);
|
|
struct ipv6_pinfo *np = inet6_sk(sk);
|
|
struct sk_buff *skb;
|
|
unsigned int maxfraglen, fragheaderlen;
|
|
int exthdrlen;
|
|
int hh_len;
|
|
int mtu;
|
|
int copy;
|
|
int err;
|
|
int offset = 0;
|
|
int csummode = CHECKSUM_NONE;
|
|
|
|
if (flags&MSG_PROBE)
|
|
return 0;
|
|
if (skb_queue_empty(&sk->sk_write_queue)) {
|
|
/*
|
|
* setup for corking
|
|
*/
|
|
if (opt) {
|
|
if (WARN_ON(np->cork.opt))
|
|
return -EINVAL;
|
|
|
|
np->cork.opt = kmalloc(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->u.dst);
|
|
inet->cork.dst = &rt->u.dst;
|
|
inet->cork.fl = *fl;
|
|
np->cork.hop_limit = hlimit;
|
|
np->cork.tclass = tclass;
|
|
mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ?
|
|
rt->u.dst.dev->mtu : dst_mtu(rt->u.dst.path);
|
|
if (np->frag_size < mtu) {
|
|
if (np->frag_size)
|
|
mtu = np->frag_size;
|
|
}
|
|
inet->cork.fragsize = mtu;
|
|
if (dst_allfrag(rt->u.dst.path))
|
|
inet->cork.flags |= IPCORK_ALLFRAG;
|
|
inet->cork.length = 0;
|
|
sk->sk_sndmsg_page = NULL;
|
|
sk->sk_sndmsg_off = 0;
|
|
exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0) -
|
|
rt->rt6i_nfheader_len;
|
|
length += exthdrlen;
|
|
transhdrlen += exthdrlen;
|
|
} else {
|
|
rt = (struct rt6_info *)inet->cork.dst;
|
|
fl = &inet->cork.fl;
|
|
opt = np->cork.opt;
|
|
transhdrlen = 0;
|
|
exthdrlen = 0;
|
|
mtu = inet->cork.fragsize;
|
|
}
|
|
|
|
hh_len = LL_RESERVED_SPACE(rt->u.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 (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) {
|
|
ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen);
|
|
return -EMSGSIZE;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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
|
|
*/
|
|
|
|
inet->cork.length += length;
|
|
if (length > mtu) {
|
|
int proto = sk->sk_protocol;
|
|
if (dontfrag && (proto == IPPROTO_UDP || proto == IPPROTO_RAW)){
|
|
ipv6_local_rxpmtu(sk, fl, mtu-exthdrlen);
|
|
return -EMSGSIZE;
|
|
}
|
|
|
|
if (proto == IPPROTO_UDP &&
|
|
(rt->u.dst.dev->features & NETIF_F_UFO)) {
|
|
|
|
err = ip6_ufo_append_data(sk, getfrag, from, length,
|
|
hh_len, fragheaderlen,
|
|
transhdrlen, mtu, flags);
|
|
if (err)
|
|
goto error;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL)
|
|
goto alloc_new_skb;
|
|
|
|
while (length > 0) {
|
|
/* Check if the remaining data fits into current packet. */
|
|
copy = (inet->cork.length <= mtu && !(inet->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;
|
|
struct sk_buff *skb_prev;
|
|
alloc_new_skb:
|
|
skb_prev = skb;
|
|
|
|
/* There's no room in the current skb */
|
|
if (skb_prev)
|
|
fraggap = skb_prev->len - maxfraglen;
|
|
else
|
|
fraggap = 0;
|
|
|
|
/*
|
|
* If remaining data exceeds the mtu,
|
|
* we know we need more fragment(s).
|
|
*/
|
|
datalen = length + fraggap;
|
|
if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
|
|
datalen = maxfraglen - fragheaderlen;
|
|
|
|
fraglen = datalen + fragheaderlen;
|
|
if ((flags & MSG_MORE) &&
|
|
!(rt->u.dst.dev->features&NETIF_F_SG))
|
|
alloclen = mtu;
|
|
else
|
|
alloclen = datalen + fragheaderlen;
|
|
|
|
/*
|
|
* The last fragment gets additional space at tail.
|
|
* Note: we overallocate on fragments with MSG_MODE
|
|
* because we have no idea if we're the last one.
|
|
*/
|
|
if (datalen == length + fraggap)
|
|
alloclen += rt->u.dst.trailer_len;
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
if (skb == NULL)
|
|
goto error;
|
|
/*
|
|
* Fill in the control structures
|
|
*/
|
|
skb->ip_summed = csummode;
|
|
skb->csum = 0;
|
|
/* reserve for fragmentation */
|
|
skb_reserve(skb, hh_len+sizeof(struct frag_hdr));
|
|
|
|
/*
|
|
* 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;
|
|
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->u.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 != frag->page) {
|
|
if (i == MAX_SKB_FRAGS) {
|
|
err = -EMSGSIZE;
|
|
goto error;
|
|
}
|
|
get_page(page);
|
|
skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0);
|
|
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;
|
|
}
|
|
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, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) {
|
|
err = -EFAULT;
|
|
goto error;
|
|
}
|
|
sk->sk_sndmsg_off += copy;
|
|
frag->size += 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:
|
|
inet->cork.length -= length;
|
|
IP6_INC_STATS(sock_net(sk), rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
|
|
return err;
|
|
}
|
|
|
|
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.dst) {
|
|
dst_release(inet->cork.dst);
|
|
inet->cork.dst = NULL;
|
|
inet->cork.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.dst;
|
|
struct flowi *fl = &inet->cork.fl;
|
|
unsigned char proto = fl->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;
|
|
|
|
ipv6_addr_copy(final_dst, &fl->fl6_dst);
|
|
__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 = fl->fl6_flowlabel |
|
|
htonl(0x60000000 | ((int)np->cork.tclass << 20));
|
|
|
|
hdr->hop_limit = np->cork.hop_limit;
|
|
hdr->nexthdr = proto;
|
|
ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
|
|
ipv6_addr_copy(&hdr->daddr, final_dst);
|
|
|
|
skb->priority = sk->sk_priority;
|
|
skb->mark = sk->sk_mark;
|
|
|
|
skb_dst_set(skb, dst_clone(&rt->u.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_BH(net, idev, icmp6_hdr(skb)->icmp6_type);
|
|
ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTMSGS);
|
|
}
|
|
|
|
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));
|
|
}
|