Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 127 insertions, 0 deletions

diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c
new file mode 100644
index 000000000000..77094aac6c28
--- /dev/null
+++ b/net/ipv4/ip_forward.c
@@ -0,0 +1,127 @@
+/*
+ * INET         An implementation of the TCP/IP protocol suite for the LINUX
+ *              operating system.  INET is implemented using the  BSD Socket
+ *              interface as the means of communication with the user level.
+ *
+ *              The IP forwarding functionality.
+ *              
+ * Version:     $Id: ip_forward.c,v 1.48 2000/12/13 18:31:48 davem Exp $
+ *
+ * Authors:     see ip.c
+ *
+ * Fixes:
+ *              Many            :       Split from ip.c , see ip_input.c for 
+ *                                      history.
+ *              Dave Gregorich  :       NULL ip_rt_put fix for multicast 
+ *                                      routing.
+ *              Jos Vos         :       Add call_out_firewall before sending,
+ *                                      use output device for accounting.
+ *              Jos Vos         :       Call forward firewall after routing
+ *                                      (always use output device).
+ *              Mike McLagan    :       Routing by source
+ */
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/skbuff.h>
+#include <linux/ip.h>
+#include <linux/icmp.h>
+#include <linux/netdevice.h>
+#include <net/sock.h>
+#include <net/ip.h>
+#include <net/tcp.h>
+#include <net/udp.h>
+#include <net/icmp.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/netfilter_ipv4.h>
+#include <net/checksum.h>
+#include <linux/route.h>
+#include <net/route.h>
+#include <net/xfrm.h>
+
+static inline int ip_forward_finish(struct sk_buff *skb)
+{
+        struct ip_options * opt = &(IPCB(skb)->opt);
+
+        IP_INC_STATS_BH(IPSTATS_MIB_OUTFORWDATAGRAMS);
+
+        if (unlikely(opt->optlen))
+                ip_forward_options(skb);
+
+        return dst_output(skb);
+}
+
+int ip_forward(struct sk_buff *skb)
+{
+        struct iphdr *iph;      /* Our header */
+        struct rtable *rt;      /* Route we use */
+        struct ip_options * opt = &(IPCB(skb)->opt);
+
+        if (!xfrm4_policy_check(NULL, XFRM_POLICY_FWD, skb))
+                goto drop;
+
+        if (IPCB(skb)->opt.router_alert && ip_call_ra_chain(skb))
+                return NET_RX_SUCCESS;
+
+        if (skb->pkt_type != PACKET_HOST)
+                goto drop;
+
+        skb->ip_summed = CHECKSUM_NONE;
+        
+        /*
+         *      According to the RFC, we must first decrease the TTL field. If
+         *      that reaches zero, we must reply an ICMP control message telling
+         *      that the packet's lifetime expired.
+         */
+
+        iph = skb->nh.iph;
+
+        if (iph->ttl <= 1)
+                goto too_many_hops;
+
+        if (!xfrm4_route_forward(skb))
+                goto drop;
+
+        iph = skb->nh.iph;
+        rt = (struct rtable*)skb->dst;
+
+        if (opt->is_strictroute && rt->rt_dst != rt->rt_gateway)
+                goto sr_failed;
+
+        /* We are about to mangle packet. Copy it! */
+        if (skb_cow(skb, LL_RESERVED_SPACE(rt->u.dst.dev)+rt->u.dst.header_len))
+                goto drop;
+        iph = skb->nh.iph;
+
+        /* Decrease ttl after skb cow done */
+        ip_decrease_ttl(iph);
+
+        /*
+         *      We now generate an ICMP HOST REDIRECT giving the route
+         *      we calculated.
+         */
+        if (rt->rt_flags&RTCF_DOREDIRECT && !opt->srr)
+                ip_rt_send_redirect(skb);
+
+        skb->priority = rt_tos2priority(iph->tos);
+
+        return NF_HOOK(PF_INET, NF_IP_FORWARD, skb, skb->dev, rt->u.dst.dev,
+                       ip_forward_finish);
+
+sr_failed:
+        /*
+         *      Strict routing permits no gatewaying
+         */
+         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_SR_FAILED, 0);
+         goto drop;
+
+too_many_hops:
+        /* Tell the sender its packet died... */
+        icmp_send(skb, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL, 0);
+drop:
+        kfree_skb(skb);
+        return NET_RX_DROP;
+}