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On Solaris, for 64-bit builds, use the 64-bit pcap-config.
[tcpdump] / print-gre.c
diff --git a/print-gre.c b/print-gre.c
index 1e801b91112123df9725efca53d4c1e2ac9a58fc..b1a814298b5571cb3bc292cf47e2cec0a5cd169b 100644 (file)
--- a/print-gre.c
+++ b/print-gre.c
@@ -1,134 +1,414 @@
+/*     $OpenBSD: print-gre.c,v 1.6 2002/10/30 03:04:04 fgsch Exp $     */
+
 /*
 /*
- * Copyright (c) 1996
- *      The Regents of the University of California.  All rights reserved.
- *
- * Redistribution and use in source and binary forms are permitted
- * provided that the above copyright notice and this paragraph are
- * duplicated in all such forms and that any documentation,
- * advertising materials, and other materials related to such
- * distribution and use acknowledge that the software was developed
- * by the University of California, Lawrence Berkeley Laboratory,
- * Berkeley, CA.  The name of the University may not be used to
- * endorse or promote products derived from this software without
- * specific prior written permission.
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
- * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ * Copyright (c) 2002 Jason L. Wright ([email protected])
+ * All rights reserved.
  *
  *
- * Initial contribution from John Hawkinson <[email protected]>
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
  *
  *
- * This module implements support for decoding GRE (Generic Routing
- * Encapsulation) tunnels; they're documented in RFC1701 and RFC1702.
- * This code only supports the IP encapsulation thereof.
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
  */
 
  */
 
-#ifndef lint
-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-gre.c,v 1.9 2000-12-18 05:41:59 guy Exp $";
-#endif
+/* \summary: Generic Routing Encapsulation (GRE) printer */
+
+/*
+ * netdissect printer for GRE - Generic Routing Encapsulation
+ * RFC1701 (GRE), RFC1702 (GRE IPv4), and RFC2637 (Enhanced GRE)
+ */
 
 #ifdef HAVE_CONFIG_H
 
 #ifdef HAVE_CONFIG_H
-#include "config.h"
+#include <config.h>
 #endif
 
 #endif
 
-#include <sys/param.h>
-#include <sys/time.h>
-#include <sys/uio.h>
-#include <sys/socket.h>
-
-#include <netinet/in.h>
-
-#include <netdb.h>
-#include <stdio.h>
-
-#include "interface.h"
-#include "addrtoname.h"
-#include "extract.h"           /* must come after interface.h */
-
-#define GRE_SIZE (20)
-
-struct gre {
-       u_short flags;
-       u_short proto;
-       union {
-               struct gre_ckof {
-                       u_short cksum;
-                       u_short offset;
-               }        gre_ckof;
-               u_int32_t key;
-               u_int32_t seq;
-       }     gre_void1;
-       union {
-               u_int32_t key;
-               u_int32_t seq;
-               u_int32_t routing;
-       }     gre_void2;
-       union {
-               u_int32_t seq;
-               u_int32_t routing;
-       }     gre_void3;
-       union {
-               u_int32_t routing;
-       }     gre_void4;
+#include "netdissect-stdinc.h"
+
+#include "netdissect.h"
+#include "addrtostr.h"
+#include "extract.h"
+#include "ethertype.h"
+
+
+#define        GRE_CP          0x8000          /* checksum present */
+#define        GRE_RP          0x4000          /* routing present */
+#define        GRE_KP          0x2000          /* key present */
+#define        GRE_SP          0x1000          /* sequence# present */
+#define        GRE_sP          0x0800          /* source routing */
+#define        GRE_AP          0x0080          /* acknowledgment# present */
+
+static const struct tok gre_flag_values[] = {
+    { GRE_CP, "checksum present"},
+    { GRE_RP, "routing present"},
+    { GRE_KP, "key present"},
+    { GRE_SP, "sequence# present"},
+    { GRE_sP, "source routing present"},
+    { GRE_AP, "ack present"},
+    { 0, NULL }
 };
 
 };
 
-#define GRE_CP         0x8000  /* Checksum Present */
-#define GRE_RP         0x4000  /* Routing Present */
-#define GRE_KP         0x2000  /* Key Present */
-#define GRE_SP         0x1000  /* Sequence Present */
+#define        GRE_RECRS_MASK  0x0700          /* recursion count */
+#define        GRE_VERS_MASK   0x0007          /* protocol version */
 
 
+/* source route entry types */
+#define        GRESRE_IP       0x0800          /* IP */
+#define        GRESRE_ASN      0xfffe          /* ASN */
+
+static void gre_print_0(netdissect_options *, const u_char *, u_int);
+static void gre_print_1(netdissect_options *, const u_char *, u_int);
+static int gre_sre_print(netdissect_options *, uint16_t, uint8_t, uint8_t, const u_char *, u_int);
+static int gre_sre_ip_print(netdissect_options *, uint8_t, uint8_t, const u_char *, u_int);
+static int gre_sre_asn_print(netdissect_options *, uint8_t, uint8_t, const u_char *, u_int);
 
 
-/*
- * Deencapsulate and print a GRE-tunneled IP datagram
- */
 void
 void
-gre_print(const u_char *bp, u_int length)
+gre_print(netdissect_options *ndo, const u_char *bp, u_int length)
+{
+       u_int len = length, vers;
+
+       ndo->ndo_protocol = "gre";
+       ND_TCHECK_2(bp);
+       if (len < 2)
+               goto trunc;
+       vers = GET_BE_U_2(bp) & GRE_VERS_MASK;
+       ND_PRINT("GREv%u",vers);
+
+       switch(vers) {
+       case 0:
+               gre_print_0(ndo, bp, len);
+               break;
+       case 1:
+               gre_print_1(ndo, bp, len);
+               break;
+       default:
+               ND_PRINT(" ERROR: unknown-version");
+               break;
+       }
+       return;
+
+trunc:
+       nd_print_trunc(ndo);
+}
+
+static void
+gre_print_0(netdissect_options *ndo, const u_char *bp, u_int length)
+{
+       u_int len = length;
+       uint16_t flags, prot;
+
+       /* 16 bits ND_TCHECKed in gre_print() */
+       flags = GET_BE_U_2(bp);
+       if (ndo->ndo_vflag)
+               ND_PRINT(", Flags [%s]",
+                        bittok2str(gre_flag_values,"none",flags));
+
+       len -= 2;
+       bp += 2;
+
+       ND_TCHECK_2(bp);
+       if (len < 2)
+               goto trunc;
+       prot = GET_BE_U_2(bp);
+       len -= 2;
+       bp += 2;
+
+       if ((flags & GRE_CP) | (flags & GRE_RP)) {
+               ND_TCHECK_2(bp);
+               if (len < 2)
+                       goto trunc;
+               if (ndo->ndo_vflag)
+                       ND_PRINT(", sum 0x%x", GET_BE_U_2(bp));
+               bp += 2;
+               len -= 2;
+
+               ND_TCHECK_2(bp);
+               if (len < 2)
+                       goto trunc;
+               ND_PRINT(", off 0x%x", GET_BE_U_2(bp));
+               bp += 2;
+               len -= 2;
+       }
+
+       if (flags & GRE_KP) {
+               ND_TCHECK_4(bp);
+               if (len < 4)
+                       goto trunc;
+               ND_PRINT(", key=0x%x", GET_BE_U_4(bp));
+               bp += 4;
+               len -= 4;
+       }
+
+       if (flags & GRE_SP) {
+               ND_TCHECK_4(bp);
+               if (len < 4)
+                       goto trunc;
+               ND_PRINT(", seq %u", GET_BE_U_4(bp));
+               bp += 4;
+               len -= 4;
+       }
+
+       if (flags & GRE_RP) {
+               for (;;) {
+                       uint16_t af;
+                       uint8_t sreoff;
+                       uint8_t srelen;
+
+                       ND_TCHECK_4(bp);
+                       if (len < 4)
+                               goto trunc;
+                       af = GET_BE_U_2(bp);
+                       sreoff = GET_U_1(bp + 2);
+                       srelen = GET_U_1(bp + 3);
+                       bp += 4;
+                       len -= 4;
+
+                       if (af == 0 && srelen == 0)
+                               break;
+
+                       if (!gre_sre_print(ndo, af, sreoff, srelen, bp, len))
+                               goto trunc;
+
+                       if (len < srelen)
+                               goto trunc;
+                       bp += srelen;
+                       len -= srelen;
+               }
+       }
+
+       if (ndo->ndo_eflag)
+               ND_PRINT(", proto %s (0x%04x)",
+                        tok2str(ethertype_values,"unknown",prot), prot);
+
+       ND_PRINT(", length %u",length);
+
+       if (ndo->ndo_vflag < 1)
+               ND_PRINT(": "); /* put in a colon as protocol demarc */
+       else
+               ND_PRINT("\n\t"); /* if verbose go multiline */
+
+       switch (prot) {
+       case ETHERTYPE_IP:
+               ip_print(ndo, bp, len);
+               break;
+       case ETHERTYPE_IPV6:
+               ip6_print(ndo, bp, len);
+               break;
+       case ETHERTYPE_MPLS:
+               mpls_print(ndo, bp, len);
+               break;
+       case ETHERTYPE_IPX:
+               ipx_print(ndo, bp, len);
+               break;
+       case ETHERTYPE_ATALK:
+               atalk_print(ndo, bp, len);
+               break;
+       case ETHERTYPE_GRE_ISO:
+               isoclns_print(ndo, bp, len);
+               break;
+       case ETHERTYPE_TEB:
+               ether_print(ndo, bp, len, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL);
+               break;
+       default:
+               ND_PRINT("gre-proto-0x%x", prot);
+       }
+       return;
+
+trunc:
+       nd_print_trunc(ndo);
+}
+
+static void
+gre_print_1(netdissect_options *ndo, const u_char *bp, u_int length)
 {
 {
-       const u_char *cp = bp + 4;
-       const struct gre *gre;
-       u_short flags, proto, extracted_ethertype;
+       u_int len = length;
+       uint16_t flags, prot;
+
+       /* 16 bits ND_TCHECKed in gre_print() */
+       flags = GET_BE_U_2(bp);
+       len -= 2;
+       bp += 2;
 
 
-       gre = (const struct gre *)bp;
+       if (ndo->ndo_vflag)
+               ND_PRINT(", Flags [%s]",
+                        bittok2str(gre_flag_values,"none",flags));
 
 
-       if (length < GRE_SIZE) {
+       ND_TCHECK_2(bp);
+       if (len < 2)
                goto trunc;
                goto trunc;
+       prot = GET_BE_U_2(bp);
+       len -= 2;
+       bp += 2;
+
+
+       if (flags & GRE_KP) {
+               uint32_t k;
+
+               ND_TCHECK_4(bp);
+               if (len < 4)
+                       goto trunc;
+               k = GET_BE_U_4(bp);
+               ND_PRINT(", call %u", k & 0xffff);
+               len -= 4;
+               bp += 4;
        }
        }
-       flags = EXTRACT_16BITS(&gre->flags);
-       proto = EXTRACT_16BITS(&gre->proto);
-
-       if (vflag) {
-               /* Decode the flags */
-               putchar('[');
-               if (flags & GRE_CP)
-                       putchar('C');
-               if (flags & GRE_RP)
-                       putchar('R');
-               if (flags & GRE_KP)
-                       putchar('K');
-               if (flags & GRE_SP)
-                       putchar('S');
-               fputs("] ", stdout);
-       }
-       /* Checksum & Offset are present */
-       if ((flags & GRE_CP) | (flags & GRE_RP))
-               cp += 4;
-
-       /* We don't support routing fields (variable length) now. Punt. */
-       if (flags & GRE_RP)
+
+       if (flags & GRE_SP) {
+               ND_TCHECK_4(bp);
+               if (len < 4)
+                       goto trunc;
+               ND_PRINT(", seq %u", GET_BE_U_4(bp));
+               bp += 4;
+               len -= 4;
+       }
+
+       if (flags & GRE_AP) {
+               ND_TCHECK_4(bp);
+               if (len < 4)
+                       goto trunc;
+               ND_PRINT(", ack %u", GET_BE_U_4(bp));
+               bp += 4;
+               len -= 4;
+       }
+
+       if ((flags & GRE_SP) == 0)
+               ND_PRINT(", no-payload");
+
+       if (ndo->ndo_eflag)
+               ND_PRINT(", proto %s (0x%04x)",
+                        tok2str(ethertype_values,"unknown",prot), prot);
+
+       ND_PRINT(", length %u",length);
+
+       if ((flags & GRE_SP) == 0)
                return;
 
                return;
 
-       if (flags & GRE_KP)
-               cp += 4;
-       if (flags & GRE_SP)
-               cp += 4;
+       if (ndo->ndo_vflag < 1)
+               ND_PRINT(": "); /* put in a colon as protocol demarc */
+       else
+               ND_PRINT("\n\t"); /* if verbose go multiline */
 
 
-       length -= cp - bp;
-       if (ether_encap_print(proto, cp, length, length,
-           &extracted_ethertype) == 0)
-               printf("gre-proto-0x%04X", proto);
+       switch (prot) {
+       case ETHERTYPE_PPP:
+               ppp_print(ndo, bp, len);
+               break;
+       default:
+               ND_PRINT("gre-proto-0x%x", prot);
+               break;
+       }
        return;
 
 trunc:
        return;
 
 trunc:
-       fputs("[|gre]", stdout);
+       nd_print_trunc(ndo);
+}
+
+static int
+gre_sre_print(netdissect_options *ndo, uint16_t af, uint8_t sreoff,
+             uint8_t srelen, const u_char *bp, u_int len)
+{
+       int ret;
+
+       switch (af) {
+       case GRESRE_IP:
+               ND_PRINT(", (rtaf=ip");
+               ret = gre_sre_ip_print(ndo, sreoff, srelen, bp, len);
+               ND_PRINT(")");
+               break;
+       case GRESRE_ASN:
+               ND_PRINT(", (rtaf=asn");
+               ret = gre_sre_asn_print(ndo, sreoff, srelen, bp, len);
+               ND_PRINT(")");
+               break;
+       default:
+               ND_PRINT(", (rtaf=0x%x)", af);
+               ret = 1;
+       }
+       return (ret);
+}
+
+static int
+gre_sre_ip_print(netdissect_options *ndo, uint8_t sreoff, uint8_t srelen,
+                const u_char *bp, u_int len)
+{
+       const u_char *up = bp;
+       char buf[INET_ADDRSTRLEN];
+
+       if (sreoff & 3) {
+               ND_PRINT(", badoffset=%u", sreoff);
+               return (1);
+       }
+       if (srelen & 3) {
+               ND_PRINT(", badlength=%u", srelen);
+               return (1);
+       }
+       if (sreoff >= srelen) {
+               ND_PRINT(", badoff/len=%u/%u", sreoff, srelen);
+               return (1);
+       }
+
+       while (srelen != 0) {
+               ND_TCHECK_4(bp);
+               if (len < 4)
+                       return (0);
+
+               addrtostr(bp, buf, sizeof(buf));
+               ND_PRINT(" %s%s",
+                        ((bp - up) == sreoff) ? "*" : "", buf);
+
+               bp += 4;
+               len -= 4;
+               srelen -= 4;
+       }
+       return (1);
+trunc:
+       return 0;
+}
+
+static int
+gre_sre_asn_print(netdissect_options *ndo, uint8_t sreoff, uint8_t srelen,
+                 const u_char *bp, u_int len)
+{
+       const u_char *up = bp;
 
 
+       if (sreoff & 1) {
+               ND_PRINT(", badoffset=%u", sreoff);
+               return (1);
+       }
+       if (srelen & 1) {
+               ND_PRINT(", badlength=%u", srelen);
+               return (1);
+       }
+       if (sreoff >= srelen) {
+               ND_PRINT(", badoff/len=%u/%u", sreoff, srelen);
+               return (1);
+       }
+
+       while (srelen != 0) {
+               ND_TCHECK_2(bp);
+               if (len < 2)
+                       return (0);
+
+               ND_PRINT(" %s%x",
+                        ((bp - up) == sreoff) ? "*" : "", GET_BE_U_2(bp));
+
+               bp += 2;
+               len -= 2;
+               srelen -= 2;
+       }
+       return (1);
+trunc:
+       return 0;
 }
 }
[mirror] the TCPdump network dissector