patch-2.1.30 linux/net/ipv6/ip6_input.c

• Lines: 409
• Date: Thu Mar 20 18:17:15 1997
• Orig file: v2.1.29/linux/net/ipv6/ip6_input.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.29/linux/net/ipv6/ip6_input.c linux/net/ipv6/ip6_input.c
@@ -0,0 +1,408 @@
+/*
+ *	IPv6 input
+ *	Linux INET6 implementation 
+ *
+ *	Authors:
+ *	Pedro Roque		<roque@di.fc.ul.pt>
+ *	Ian P. Morris		<I.P.Morris@soton.ac.uk>
+ *
+ *	$Id: ip6_input.c,v 1.4 1997/03/18 18:24:35 davem Exp $
+ *
+ *	Based in linux/net/ipv4/ip_input.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.
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/sched.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/in6.h>
+#include <linux/icmpv6.h>
+
+#include <net/sock.h>
+#include <net/snmp.h>
+
+#include <net/ipv6.h>
+#include <net/protocol.h>
+#include <net/transp_v6.h>
+#include <net/rawv6.h>
+#include <net/ndisc.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+
+static int ipv6_dest_opt(struct sk_buff **skb_ptr, struct device *dev,
+			 __u8 *nhptr, struct ipv6_options *opt);
+
+struct hdrtype_proc {
+	u8	type;
+	int	(*func) (struct sk_buff **, struct device *dev, __u8 *ptr,
+			 struct ipv6_options *opt);
+} hdrproc_lst[] = {
+
+  /*
+	TODO
+
+	{NEXTHDR_HOP,		ipv6_hop_by_hop}
+	{NEXTHDR_ROUTING,	ipv6_routing_header},
+   */
+	{NEXTHDR_FRAGMENT,	ipv6_reassembly},
+  
+	{NEXTHDR_DEST,		ipv6_dest_opt},
+   /*	
+	{NEXTHDR_AUTH,		ipv6_auth_hdr},
+	{NEXTHDR_ESP,		ipv6_esp_hdr},
+    */
+	{NEXTHDR_MAX,		NULL}
+};
+
+/* New header structures */
+
+
+struct ipv6_tlvtype {
+	u8 type;
+	u8 len;
+};
+
+struct ipv6_destopt_hdr {
+	u8 nexthdr;
+	u8 hdrlen;
+};
+
+
+struct tlvtype_proc {
+	u8	type;
+	int	(*func) (struct sk_buff *, struct device *dev, __u8 *ptr,
+			 struct ipv6_options *opt);
+	/*
+	 *	these functions do NOT update skb->h.raw
+	 */
+
+} tlvprocdestopt_lst[] = {
+	{255,			NULL}
+};
+
+static int ip6_dstopt_unknown(struct sk_buff *skb, struct ipv6_tlvtype *hdr)
+{
+	struct in6_addr *daddr;
+	int pos;
+
+	/*
+	 *	unkown destination option type
+	 */
+	
+	pos = (__u8 *) skb->h.raw - (__u8 *) skb->nh.raw;
+	
+	/* I think this is correct please check - IPM */
+
+	switch ((hdr->type & 0xC0) >> 6) {
+	case 0: /* ignore */
+		skb->h.raw += hdr->len+2;
+		return 1;
+		
+	case 1: /* drop packet */
+		break;
+
+	case 2: /* send ICMP PARM PROB regardless and drop packet */
+		icmpv6_send(skb, ICMPV6_PARAMPROB, ICMPV6_UNK_OPTION,
+			    pos, skb->dev);
+		break;
+		
+	case 3: /* Send ICMP if not a multicast address and drop packet */
+		daddr = &skb->nh.ipv6h->daddr;
+		if (!(ipv6_addr_type(daddr) & IPV6_ADDR_MULTICAST))
+			icmpv6_send(skb, ICMPV6_PARAMPROB,
+				    ICMPV6_UNK_OPTION, pos, skb->dev);
+	};
+	
+	kfree_skb(skb, FREE_READ);
+	return 0;
+}
+
+static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff *skb,
+			 struct device *dev, __u8 *nhptr,
+			 struct ipv6_options *opt, void *lastopt)
+{
+	struct ipv6_tlvtype *hdr;
+	struct tlvtype_proc *curr;
+
+	while ((hdr=(struct ipv6_tlvtype *)skb->h.raw) != lastopt) {
+		switch (hdr->type & 0x3F) {		
+		case 0: /* TLV encoded Pad1 */
+			skb->h.raw++;
+			break;
+
+		case 1: /* TLV encoded PadN */
+			skb->h.raw += hdr->len+2;
+			break;
+
+		default: /* Other TLV code so scan list */
+			for (curr=procs; curr->type != 255; curr++) {
+				if (curr->type == (hdr->type & 0x3F)) {
+					curr->func(skb, dev, nhptr, opt);
+					skb->h.raw += hdr->len+2;
+					break;
+				}
+			}
+			if (curr->type==255) {
+				if (ip6_dstopt_unknown(skb, hdr) == 0)
+					return 0;
+			}
+			break;
+		}
+	}
+	return 1;
+}
+
+static int ipv6_dest_opt(struct sk_buff **skb_ptr, struct device *dev,
+			 __u8 *nhptr, struct ipv6_options *opt)
+{
+	struct sk_buff *skb=*skb_ptr;
+	struct ipv6_destopt_hdr *hdr = (struct ipv6_destopt_hdr *) skb->h.raw;
+	int res = 0;
+
+	if (ip6_parse_tlv(tlvprocdestopt_lst, skb, dev, nhptr, opt,
+			  skb->h.raw+hdr->hdrlen))
+		res = hdr->nexthdr;
+
+	return res;
+}
+
+
+int ipv6_rcv(struct sk_buff *skb, struct device *dev, struct packet_type *pt)
+{
+	struct ipv6hdr *hdr;
+	int pkt_len;
+
+	if (skb->pkt_type == PACKET_OTHERHOST) {
+		kfree_skb(skb, FREE_READ);
+		return 0;
+	}
+
+	hdr = skb->nh.ipv6h;
+
+	if (skb->len < sizeof(struct ipv6hdr) || hdr->version != 6)
+		goto err;
+
+	pkt_len = ntohs(hdr->payload_len);
+
+	if (pkt_len + sizeof(struct ipv6hdr) > skb->len)
+		goto err;
+
+	skb_trim(skb, pkt_len + sizeof(struct ipv6hdr));
+
+	ip6_route_input(skb);
+	
+	return 0;
+err:
+	ipv6_statistics.Ip6InHdrErrors++;
+	kfree_skb(skb, FREE_READ);
+	return 0;
+}
+
+/*
+ *	0 - deliver
+ *	1 - block
+ */
+static __inline__ int icmpv6_filter(struct sock *sk, struct sk_buff *skb)
+{
+	struct icmp6hdr *icmph;
+	struct raw6_opt *opt;
+
+	opt = &sk->tp_pinfo.tp_raw;
+	icmph = (struct icmp6hdr *) (skb->nh.ipv6h + 1);
+	return test_bit(icmph->icmp6_type, &opt->filter);
+}
+
+/*
+ *	demultiplex raw sockets.
+ *	(should consider queueing the skb in the sock receive_queue
+ *	without calling rawv6.c)
+ */
+static struct sock * ipv6_raw_deliver(struct sk_buff *skb,
+				      struct ipv6_options *opt,
+				      int nexthdr, int len)
+{
+	struct in6_addr *saddr;
+	struct in6_addr *daddr;
+	struct sock *sk, *sk2;
+	__u8 hash;
+
+	saddr = &skb->nh.ipv6h->saddr;
+	daddr = saddr + 1;
+
+	hash = nexthdr & (MAX_INET_PROTOS - 1);
+
+	sk = raw_v6_htable[hash];
+
+	/*
+	 *	The first socket found will be delivered after
+	 *	delivery to transport protocols.
+	 */
+
+	if (sk == NULL)
+		return NULL;
+
+	sk = raw_v6_lookup(sk, nexthdr, daddr, saddr);
+
+	if (sk) {
+		sk2 = sk;
+
+		while ((sk2 = raw_v6_lookup(sk2->next, nexthdr, daddr, saddr))) {
+			struct sk_buff *buff;
+
+			if (nexthdr == IPPROTO_ICMPV6 &&
+			    icmpv6_filter(sk2, skb))
+				continue;
+
+			buff = skb_clone(skb, GFP_ATOMIC);
+			buff->sk = sk2;
+			rawv6_rcv(buff, skb->dev, saddr, daddr, opt, len);
+		}
+	}
+
+	if (sk && nexthdr == IPPROTO_ICMPV6 && icmpv6_filter(sk, skb))
+		sk = NULL;
+
+	return sk;
+}
+
+/*
+ *	Deliver the packet to the host
+ */
+
+int ip6_input(struct sk_buff *skb)
+{
+	struct ipv6_options *opt = (struct ipv6_options *) skb->cb;
+	struct ipv6hdr *hdr = skb->nh.ipv6h;
+	struct inet6_protocol *ipprot;
+	struct hdrtype_proc *hdrt;
+	struct sock *raw_sk;
+	__u8 *nhptr;
+	int nexthdr;
+	int found = 0;
+	u8 hash;
+	int len;
+	
+	skb->h.raw += sizeof(struct ipv6hdr);
+
+	/*
+	 *	Parse extension headers
+	 */
+
+	nexthdr = hdr->nexthdr;
+	nhptr = &hdr->nexthdr;
+
+	/*
+	 *	check for extension headers
+	 */
+
+st_loop:
+
+	for (hdrt=hdrproc_lst; hdrt->type != NEXTHDR_MAX; hdrt++) {
+		if (hdrt->type == nexthdr) {
+			if ((nexthdr = hdrt->func(&skb, skb->dev, nhptr, opt))) {
+				nhptr = skb->h.raw;
+				hdr = skb->nh.ipv6h;
+				goto st_loop;
+			}
+			return 0;
+		}
+	}
+
+	len = skb->tail - skb->h.raw;
+
+	raw_sk = ipv6_raw_deliver(skb, opt, nexthdr, len);
+
+	hash = nexthdr & (MAX_INET_PROTOS - 1);
+	for (ipprot = (struct inet6_protocol *) inet6_protos[hash]; 
+	     ipprot != NULL; 
+	     ipprot = (struct inet6_protocol *) ipprot->next) {
+		struct sk_buff *buff = skb;
+		
+		if (ipprot->protocol != nexthdr)
+			continue;
+		
+		if (ipprot->copy || raw_sk)
+			buff = skb_clone(skb, GFP_ATOMIC);
+		
+		
+		ipprot->handler(buff, skb->dev, &hdr->saddr, &hdr->daddr,
+				opt, len, 0, ipprot);
+		found = 1;
+	}
+	
+	if (raw_sk) {
+		skb->sk = raw_sk;
+		rawv6_rcv(skb, skb->dev, &hdr->saddr, &hdr->daddr, opt, len);
+		found = 1;
+	}
+	
+	/*
+	 *	not found: send ICMP parameter problem back
+	 */
+	
+	if (!found) {
+		unsigned long offset;
+#if IP6_DEBUG >= 2
+		printk(KERN_DEBUG "proto not found %d\n", nexthdr);
+#endif
+		offset = nhptr - (u8*) hdr;
+		icmpv6_send(skb, ICMPV6_PARAMPROB, ICMPV6_UNK_NEXTHDR,
+			    offset, skb->dev);
+		kfree_skb(skb, FREE_READ);
+	}
+
+	return 0;
+}
+
+int ip6_mc_input(struct sk_buff *skb)
+{
+	struct ipv6hdr *hdr;	
+	int deliver = 0;
+	int discard = 1;
+
+	hdr = skb->nh.ipv6h;
+	if (ipv6_chk_mcast_addr(skb->dev, &hdr->daddr))
+		deliver = 1;
+
+#if 0
+	if (ipv6_config.multicast_route) {
+		int addr_type;
+
+		addr_type = ipv6_addr_type(&hdr->daddr);
+
+		if (!(addr_type & (IPV6_ADDR_LOOPBACK | IPV6_ADDR_LINKLOCAL))) {
+			struct sk_buff *skb2;
+			struct dst_entry *dst;
+
+			dst = skb->dst;
+			
+			if (deliver) {
+				skb2 = skb_clone(skb, GFP_ATOMIC);
+			} else {
+				discard = 0;
+				skb2 = skb;
+			}
+
+			dst->output(skb2);
+		}
+	}
+#endif
+
+	if (deliver) {
+		discard = 0;
+		ip6_input(skb);
+	}
+
+	if (discard)
+		kfree_skb(skb, FREE_READ);
+
+	return 0;
+}