diff options
Diffstat (limited to 'net/ipv6/ip6_output.c')
| -rw-r--r-- | net/ipv6/ip6_output.c | 1686 |
1 files changed, 1686 insertions, 0 deletions
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c new file mode 100644 index 00000000..13e5399b --- /dev/null +++ b/net/ipv6/ip6_output.c @@ -0,0 +1,1686 @@ +/* + * 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> + +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_BH(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 = + (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; +} + +void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt) +{ + static atomic_t ipv6_fragmentation_id; + int old, new; + + if (rt && !(rt->dst.flags & DST_NOPEER)) { + struct inet_peer *peer; + + if (!rt->rt6i_peer) + rt6_bind_peer(rt, 1); + peer = rt->rt6i_peer; + if (peer) { + fhdr->identification = htonl(inet_getid(peer, 0)); + return; + } + } + do { + old = atomic_read(&ipv6_fragmentation_id); + new = old + 1; + if (!new) + new = 1; + } while (atomic_cmpxchg(&ipv6_fragmentation_id, old, new) != old); + fhdr->identification = htonl(new); +} + +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); + 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 = (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, &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) { + 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; + } + + 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, rt); + 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; +} + +static void ip6_append_data_mtu(int *mtu, + int *maxfraglen, + unsigned int fragheaderlen, + struct sk_buff *skb, + struct rt6_info *rt) +{ + if (!(rt->dst.flags & DST_XFRM_TUNNEL)) { + if (skb == NULL) { + /* first fragment, reserve header_len */ + *mtu = *mtu - rt->dst.header_len; + + } else { + /* + * this fragment is not first, the headers + * space is regarded as data space. + */ + *mtu = dst_mtu(rt->dst.path); + } + *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; + int exthdrlen; + int dst_exthdrlen; + int hh_len; + int mtu; + 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 = 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->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) - rt->rt6i_nfheader_len; + length += exthdrlen; + transhdrlen += exthdrlen; + dst_exthdrlen = rt->dst.header_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; + } + + 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 + */ + + cork->length += length; + if (length > mtu) { + int proto = sk->sk_protocol; + if (dontfrag && (proto == IPPROTO_UDP || proto == IPPROTO_RAW)){ + ipv6_local_rxpmtu(sk, fl6, mtu-exthdrlen); + return -EMSGSIZE; + } + + if (proto == 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 = 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 = (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); + + 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; + } + 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; +} + +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_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)); +} |