iproute2-2.6.23: RFC4214 Support (v2.5)

This patch includes support for the Intra-Site Automatic Tunnel
Addressing Protocol (ISATAP) per RFC4214.

The following diffs are specific to the iproute2-2.6.23
software distribution. This message includes the full and
patchable diff text; please use this version to apply patches.
Signed-off-by: Fred L. Templin <fred.l.templin@boeing.com>
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>

include/linux/if_tunnel.h

+#ifndef _IF_TUNNEL_H_
+#define _IF_TUNNEL_H_
+
+#include <linux/types.h>
+
+#define SIOCGETTUNNEL   (SIOCDEVPRIVATE + 0)
+#define SIOCADDTUNNEL   (SIOCDEVPRIVATE + 1)
+#define SIOCDELTUNNEL   (SIOCDEVPRIVATE + 2)
+#define SIOCCHGTUNNEL   (SIOCDEVPRIVATE + 3)
+
+#define GRE_CSUM	__constant_htons(0x8000)
+#define GRE_ROUTING	__constant_htons(0x4000)
+#define GRE_KEY		__constant_htons(0x2000)
+#define GRE_SEQ		__constant_htons(0x1000)
+#define GRE_STRICT	__constant_htons(0x0800)
+#define GRE_REC		__constant_htons(0x0700)
+#define GRE_FLAGS	__constant_htons(0x00F8)
+#define GRE_VERSION	__constant_htons(0x0007)
+
+/* i_flags values for SIT mode */
+#define	SIT_ISATAP	0x0001
+
+struct ip_tunnel_parm
+{
+	char			name[IFNAMSIZ];
+	int			link;
+	__be16			i_flags;
+	__be16			o_flags;
+	__be32			i_key;
+	__be32			o_key;
+	struct iphdr		iph;
+};
+
+#endif /* _IF_TUNNEL_H_ */

ip/iptunnel.c

@@ -39,7 +39,7 @@ static void usage(void) __attribute__((noreturn));
 static void usage(void)
 {
 	fprintf(stderr, "Usage: ip tunnel { add | change | del | show } [ NAME ]\n");
-	fprintf(stderr, "          [ mode { ipip | gre | sit } ] [ remote ADDR ] [ local ADDR ]\n");
+	fprintf(stderr, "          [ mode { ipip | gre | sit | isatap } ] [ remote ADDR ] [ local ADDR ]\n");
 	fprintf(stderr, "          [ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ]\n");
 	fprintf(stderr, "          [ ttl TTL ] [ tos TOS ] [ [no]pmtudisc ] [ dev PHYS_DEV ]\n");
 	fprintf(stderr, "\n");
@@ -55,6 +55,7 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 {
 	int count = 0;
 	char medium[IFNAMSIZ];
+	int isatap = 0;
 
 	memset(p, 0, sizeof(*p));
 	memset(&medium, 0, sizeof(medium));
@@ -90,6 +91,13 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 					exit(-1);
 				}
 				p->iph.protocol = IPPROTO_IPV6;
+			} else if (strcmp(*argv, "isatap") == 0) {
+				if (p->iph.protocol && p->iph.protocol != IPPROTO_IPV6) {
+					fprintf(stderr, "You managed to ask for more than one tunnel mode.\n");
+					exit(-1);
+				}
+				p->iph.protocol = IPPROTO_IPV6;
+				isatap++;
 			} else {
 				fprintf(stderr,"Cannot guess tunnel mode.\n");
 				exit(-1);
@@ -212,6 +220,10 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 			p->iph.protocol = IPPROTO_IPIP;
 		else if (memcmp(p->name, "sit", 3) == 0)
 			p->iph.protocol = IPPROTO_IPV6;
+		else if (memcmp(p->name, "isatap", 6) == 0) {
+			p->iph.protocol = IPPROTO_IPV6;
+			isatap++;
+		}
 	}
 
 	if (p->iph.protocol == IPPROTO_IPIP || p->iph.protocol == IPPROTO_IPV6) {
@@ -239,6 +251,14 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 		fprintf(stderr, "Broadcast tunnel requires a source address.\n");
 		return -1;
 	}
+	if (isatap) {
+		if (p->iph.daddr) {
+			fprintf(stderr, "no remote with isatap.\n");
+			return -1;
+		}
+		p->i_flags |= SIT_ISATAP;
+	}
+
 	return 0;
 }