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-rw-r--r--print-dvmrp.c332
1 files changed, 332 insertions, 0 deletions
diff --git a/print-dvmrp.c b/print-dvmrp.c
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+++ b/print-dvmrp.c
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+/*
+ * Copyright (c) 1995, 1996
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that: (1) source code distributions
+ * retain the above copyright notice and this paragraph in its entirety, (2)
+ * distributions including binary code include the above copyright notice and
+ * this paragraph in its entirety in the documentation or other materials
+ * provided with the distribution, and (3) all advertising materials mentioning
+ * features or use of this software display the following acknowledgement:
+ * ``This product includes software developed by the University of California,
+ * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
+ * the University nor the names of its contributors may 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
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+/* \summary: Distance Vector Multicast Routing Protocol printer */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "netdissect-stdinc.h"
+
+#include "netdissect.h"
+#include "extract.h"
+#include "addrtoname.h"
+
+/*
+ * See: RFC 1075 and draft-ietf-idmr-dvmrp-v3
+ *
+ * DVMRP message types and flag values shamelessly stolen from
+ * mrouted/dvmrp.h.
+ */
+#define DVMRP_PROBE 1 /* for finding neighbors */
+#define DVMRP_REPORT 2 /* for reporting some or all routes */
+#define DVMRP_ASK_NEIGHBORS 3 /* sent by mapper, asking for a list */
+ /* of this router's neighbors */
+#define DVMRP_NEIGHBORS 4 /* response to such a request */
+#define DVMRP_ASK_NEIGHBORS2 5 /* as above, want new format reply */
+#define DVMRP_NEIGHBORS2 6
+#define DVMRP_PRUNE 7 /* prune message */
+#define DVMRP_GRAFT 8 /* graft message */
+#define DVMRP_GRAFT_ACK 9 /* graft acknowledgement */
+static const struct tok dvmrp_msgtype_str[] = {
+ { DVMRP_PROBE, "Probe" },
+ { DVMRP_REPORT, "Report" },
+ { DVMRP_ASK_NEIGHBORS, "Ask-neighbors(old)" },
+ { DVMRP_NEIGHBORS, "Neighbors(old)" },
+ { DVMRP_ASK_NEIGHBORS2, "Ask-neighbors2" },
+ { DVMRP_NEIGHBORS2, "Neighbors2" },
+ { DVMRP_PRUNE, "Prune" },
+ { DVMRP_GRAFT, "Graft" },
+ { DVMRP_GRAFT_ACK, "Graft-ACK" },
+ { 0, NULL }
+};
+
+/*
+ * 'flags' byte values in DVMRP_NEIGHBORS2 reply.
+ */
+#define DVMRP_NF_TUNNEL 0x01 /* neighbors reached via tunnel */
+#define DVMRP_NF_SRCRT 0x02 /* tunnel uses IP source routing */
+#define DVMRP_NF_DOWN 0x10 /* kernel state of interface */
+#define DVMRP_NF_DISABLED 0x20 /* administratively disabled */
+#define DVMRP_NF_QUERIER 0x40 /* I am the subnet's querier */
+
+static void print_probe(netdissect_options *, const u_char *, u_int);
+static void print_report(netdissect_options *, const u_char *, u_int);
+static void print_neighbors(netdissect_options *, const u_char *, u_int);
+static void print_neighbors2(netdissect_options *, const u_char *, u_int, uint8_t, uint8_t);
+
+void
+dvmrp_print(netdissect_options *ndo,
+ const u_char *bp, u_int len)
+{
+ u_char type;
+ uint8_t major_version, minor_version;
+
+ ndo->ndo_protocol = "dvmrp";
+ if (len < 8) {
+ ND_PRINT(" [length %u < 8]", len);
+ goto invalid;
+ }
+
+ type = GET_U_1(bp + 1);
+
+ /* Skip IGMP header */
+ bp += 8;
+ len -= 8;
+
+ ND_PRINT(" %s", tok2str(dvmrp_msgtype_str, "[type %u]", type));
+ switch (type) {
+
+ case DVMRP_PROBE:
+ if (ndo->ndo_vflag) {
+ print_probe(ndo, bp, len);
+ }
+ break;
+
+ case DVMRP_REPORT:
+ if (ndo->ndo_vflag > 1) {
+ print_report(ndo, bp, len);
+ }
+ break;
+
+ case DVMRP_NEIGHBORS:
+ print_neighbors(ndo, bp, len);
+ break;
+
+ case DVMRP_NEIGHBORS2:
+ /*
+ * extract version from IGMP group address field
+ */
+ bp -= 4;
+ major_version = GET_U_1(bp + 3);
+ minor_version = GET_U_1(bp + 2);
+ bp += 4;
+ print_neighbors2(ndo, bp, len, major_version, minor_version);
+ break;
+
+ case DVMRP_PRUNE:
+ ND_PRINT(" src %s grp %s", GET_IPADDR_STRING(bp), GET_IPADDR_STRING(bp + 4));
+ ND_PRINT(" timer ");
+ unsigned_relts_print(ndo, GET_BE_U_4(bp + 8));
+ break;
+
+ case DVMRP_GRAFT:
+ ND_PRINT(" src %s grp %s", GET_IPADDR_STRING(bp), GET_IPADDR_STRING(bp + 4));
+ break;
+
+ case DVMRP_GRAFT_ACK:
+ ND_PRINT(" src %s grp %s", GET_IPADDR_STRING(bp), GET_IPADDR_STRING(bp + 4));
+ break;
+ }
+ return;
+
+invalid:
+ nd_print_invalid(ndo);
+}
+
+static void
+print_report(netdissect_options *ndo,
+ const u_char *bp,
+ u_int len)
+{
+ uint32_t mask, origin;
+ u_int metric, done;
+ u_int i, width;
+
+ while (len > 0) {
+ if (len < 3) {
+ ND_PRINT(" [length %u < 3]", len);
+ goto invalid;
+ }
+ mask = (uint32_t)0xff << 24 | GET_U_1(bp) << 16 |
+ GET_U_1(bp + 1) << 8 | GET_U_1(bp + 2);
+ width = 1;
+ if (GET_U_1(bp))
+ width = 2;
+ if (GET_U_1(bp + 1))
+ width = 3;
+ if (GET_U_1(bp + 2))
+ width = 4;
+
+ ND_PRINT("\n\tMask %s", intoa(htonl(mask)));
+ bp += 3;
+ len -= 3;
+ do {
+ if (len < width + 1) {
+ ND_PRINT("\n\t [Truncated Report]");
+ goto invalid;
+ }
+ origin = 0;
+ for (i = 0; i < width; ++i) {
+ origin = origin << 8 | GET_U_1(bp);
+ bp++;
+ }
+ for ( ; i < 4; ++i)
+ origin <<= 8;
+
+ metric = GET_U_1(bp);
+ bp++;
+ done = metric & 0x80;
+ metric &= 0x7f;
+ ND_PRINT("\n\t %s metric %u", intoa(htonl(origin)),
+ metric);
+ len -= width + 1;
+ } while (!done);
+ }
+ return;
+
+invalid:
+ nd_print_invalid(ndo);
+}
+
+static void
+print_probe(netdissect_options *ndo,
+ const u_char *bp,
+ u_int len)
+{
+ if (len < 4) {
+ ND_PRINT(" [full length %u < 4]", len);
+ goto invalid;
+ }
+ ND_PRINT(ndo->ndo_vflag > 1 ? "\n\t" : " ");
+ ND_PRINT("genid %u", GET_BE_U_4(bp));
+ if (ndo->ndo_vflag < 2)
+ return;
+
+ bp += 4;
+ len -= 4;
+ while (len > 0) {
+ if (len < 4) {
+ ND_PRINT("[remaining length %u < 4]", len);
+ goto invalid;
+ }
+ ND_PRINT("\n\tneighbor %s", GET_IPADDR_STRING(bp));
+ bp += 4; len -= 4;
+ }
+ return;
+
+invalid:
+ nd_print_invalid(ndo);
+}
+
+static void
+print_neighbors(netdissect_options *ndo,
+ const u_char *bp,
+ u_int len)
+{
+ const u_char *laddr;
+ u_char metric;
+ u_char thresh;
+ int ncount;
+
+ while (len > 0) {
+ if (len < 7) {
+ ND_PRINT(" [length %u < 7]", len);
+ goto invalid;
+ }
+ laddr = bp;
+ bp += 4;
+ metric = GET_U_1(bp);
+ bp++;
+ thresh = GET_U_1(bp);
+ bp++;
+ ncount = GET_U_1(bp);
+ bp++;
+ len -= 7;
+ while (--ncount >= 0) {
+ if (len < 4) {
+ ND_PRINT(" [length %u < 4]", len);
+ goto invalid;
+ }
+ ND_PRINT(" [%s ->", GET_IPADDR_STRING(laddr));
+ ND_PRINT(" %s, (%u/%u)]",
+ GET_IPADDR_STRING(bp), metric, thresh);
+ bp += 4;
+ len -= 4;
+ }
+ }
+ return;
+
+invalid:
+ nd_print_invalid(ndo);
+}
+
+static void
+print_neighbors2(netdissect_options *ndo,
+ const u_char *bp,
+ u_int len, uint8_t major_version,
+ uint8_t minor_version)
+{
+ const u_char *laddr;
+ u_char metric, thresh, flags;
+ int ncount;
+
+ ND_PRINT(" (v %u.%u):", major_version, minor_version);
+
+ while (len > 0) {
+ if (len < 8) {
+ ND_PRINT(" [length %u < 8]", len);
+ goto invalid;
+ }
+ laddr = bp;
+ bp += 4;
+ metric = GET_U_1(bp);
+ bp++;
+ thresh = GET_U_1(bp);
+ bp++;
+ flags = GET_U_1(bp);
+ bp++;
+ ncount = GET_U_1(bp);
+ bp++;
+ len -= 8;
+ while (--ncount >= 0 && len > 0) {
+ if (len < 4) {
+ ND_PRINT(" [length %u < 4]", len);
+ goto invalid;
+ }
+ ND_PRINT(" [%s -> ", GET_IPADDR_STRING(laddr));
+ ND_PRINT("%s (%u/%u", GET_IPADDR_STRING(bp),
+ metric, thresh);
+ if (flags & DVMRP_NF_TUNNEL)
+ ND_PRINT("/tunnel");
+ if (flags & DVMRP_NF_SRCRT)
+ ND_PRINT("/srcrt");
+ if (flags & DVMRP_NF_QUERIER)
+ ND_PRINT("/querier");
+ if (flags & DVMRP_NF_DISABLED)
+ ND_PRINT("/disabled");
+ if (flags & DVMRP_NF_DOWN)
+ ND_PRINT("/down");
+ ND_PRINT(")]");
+ bp += 4;
+ len -= 4;
+ }
+ if (ncount != -1) {
+ ND_PRINT(" [invalid ncount]");
+ goto invalid;
+ }
+ }
+ return;
+
+invalid:
+ nd_print_invalid(ndo);
+}
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