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print-pim.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: Protocol Independent Multicast (PIM) printer */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "netdissect-stdinc.h"
#include "netdissect.h"
#include "addrtoname.h"
#include "extract.h"
#include "ip.h"
#include "ip6.h"
#include "ipproto.h"
#define PIMV1_TYPE_QUERY 0
#define PIMV1_TYPE_REGISTER 1
#define PIMV1_TYPE_REGISTER_STOP 2
#define PIMV1_TYPE_JOIN_PRUNE 3
#define PIMV1_TYPE_RP_REACHABILITY 4
#define PIMV1_TYPE_ASSERT 5
#define PIMV1_TYPE_GRAFT 6
#define PIMV1_TYPE_GRAFT_ACK 7
static const struct tok pimv1_type_str[] = {
{ PIMV1_TYPE_QUERY, "Query" },
{ PIMV1_TYPE_REGISTER, "Register" },
{ PIMV1_TYPE_REGISTER_STOP, "Register-Stop" },
{ PIMV1_TYPE_JOIN_PRUNE, "Join/Prune" },
{ PIMV1_TYPE_RP_REACHABILITY, "RP-reachable" },
{ PIMV1_TYPE_ASSERT, "Assert" },
{ PIMV1_TYPE_GRAFT, "Graft" },
{ PIMV1_TYPE_GRAFT_ACK, "Graft-ACK" },
{ 0, NULL }
};
#define PIMV2_TYPE_HELLO 0
#define PIMV2_TYPE_REGISTER 1
#define PIMV2_TYPE_REGISTER_STOP 2
#define PIMV2_TYPE_JOIN_PRUNE 3
#define PIMV2_TYPE_BOOTSTRAP 4
#define PIMV2_TYPE_ASSERT 5
#define PIMV2_TYPE_GRAFT 6
#define PIMV2_TYPE_GRAFT_ACK 7
#define PIMV2_TYPE_CANDIDATE_RP 8
#define PIMV2_TYPE_PRUNE_REFRESH 9
#define PIMV2_TYPE_DF_ELECTION 10
#define PIMV2_TYPE_ECMP_REDIRECT 11
static const struct tok pimv2_type_values[] = {
{ PIMV2_TYPE_HELLO, "Hello" },
{ PIMV2_TYPE_REGISTER, "Register" },
{ PIMV2_TYPE_REGISTER_STOP, "Register Stop" },
{ PIMV2_TYPE_JOIN_PRUNE, "Join / Prune" },
{ PIMV2_TYPE_BOOTSTRAP, "Bootstrap" },
{ PIMV2_TYPE_ASSERT, "Assert" },
{ PIMV2_TYPE_GRAFT, "Graft" },
{ PIMV2_TYPE_GRAFT_ACK, "Graft Acknowledgement" },
{ PIMV2_TYPE_CANDIDATE_RP, "Candidate RP Advertisement" },
{ PIMV2_TYPE_PRUNE_REFRESH, "Prune Refresh" },
{ PIMV2_TYPE_DF_ELECTION, "DF Election" },
{ PIMV2_TYPE_ECMP_REDIRECT, "ECMP Redirect" },
{ 0, NULL}
};
#define PIMV2_HELLO_OPTION_HOLDTIME 1
#define PIMV2_HELLO_OPTION_LANPRUNEDELAY 2
#define PIMV2_HELLO_OPTION_DR_PRIORITY_OLD 18
#define PIMV2_HELLO_OPTION_DR_PRIORITY 19
#define PIMV2_HELLO_OPTION_GENID 20
#define PIMV2_HELLO_OPTION_REFRESH_CAP 21
#define PIMV2_HELLO_OPTION_BIDIR_CAP 22
#define PIMV2_HELLO_OPTION_ADDRESS_LIST 24
#define PIMV2_HELLO_OPTION_ADDRESS_LIST_OLD 65001
static const struct tok pimv2_hello_option_values[] = {
{ PIMV2_HELLO_OPTION_HOLDTIME, "Hold Time" },
{ PIMV2_HELLO_OPTION_LANPRUNEDELAY, "LAN Prune Delay" },
{ PIMV2_HELLO_OPTION_DR_PRIORITY_OLD, "DR Priority (Old)" },
{ PIMV2_HELLO_OPTION_DR_PRIORITY, "DR Priority" },
{ PIMV2_HELLO_OPTION_GENID, "Generation ID" },
{ PIMV2_HELLO_OPTION_REFRESH_CAP, "State Refresh Capability" },
{ PIMV2_HELLO_OPTION_BIDIR_CAP, "Bi-Directional Capability" },
{ PIMV2_HELLO_OPTION_ADDRESS_LIST, "Address List" },
{ PIMV2_HELLO_OPTION_ADDRESS_LIST_OLD, "Address List (Old)" },
{ 0, NULL}
};
#define PIMV2_REGISTER_FLAG_LEN 4
#define PIMV2_REGISTER_FLAG_BORDER 0x80000000
#define PIMV2_REGISTER_FLAG_NULL 0x40000000
static const struct tok pimv2_register_flag_values[] = {
{ PIMV2_REGISTER_FLAG_BORDER, "Border" },
{ PIMV2_REGISTER_FLAG_NULL, "Null" },
{ 0, NULL}
};
#define PIMV2_DF_ELECTION_OFFER 1
#define PIMV2_DF_ELECTION_WINNER 2
#define PIMV2_DF_ELECTION_BACKOFF 3
#define PIMV2_DF_ELECTION_PASS 4
static const struct tok pimv2_df_election_flag_values[] = {
{ PIMV2_DF_ELECTION_OFFER, "Offer" },
{ PIMV2_DF_ELECTION_WINNER, "Winner" },
{ PIMV2_DF_ELECTION_BACKOFF, "Backoff" },
{ PIMV2_DF_ELECTION_PASS, "Pass" },
{ 0, NULL}
};
#define PIMV2_DF_ELECTION_PASS_BACKOFF_STR(x) ( \
x == PIMV2_DF_ELECTION_BACKOFF ? "offer" : "new winner" )
/*
* XXX: We consider a case where IPv6 is not ready yet for portability,
* but PIM dependent defintions should be independent of IPv6...
*/
struct pim {
nd_uint8_t pim_typever;
/* upper 4bit: PIM version number; 2 for PIMv2 */
/* lower 4bit: the PIM message type, currently they are:
* Hello, Register, Register-Stop, Join/Prune,
* Bootstrap, Assert, Graft (PIM-DM only),
* Graft-Ack (PIM-DM only), C-RP-Adv
*/
#define PIM_VER(x) (((x) & 0xf0) >> 4)
#define PIM_TYPE(x) ((x) & 0x0f)
nd_uint8_t pim_rsv; /* Reserved in v1, subtype+address length in v2 */
#define PIM_SUBTYPE(x) (((x) & 0xf0) >> 4)
nd_uint16_t pim_cksum; /* IP style check sum */
};
static void pimv2_print(netdissect_options *, const u_char *bp, u_int len, const u_char *);
static void
pimv1_join_prune_print(netdissect_options *ndo,
const u_char *bp, u_int len)
{
u_int ngroups, njoin, nprune;
u_int njp;
/* If it's a single group and a single source, use 1-line output. */
if (ND_TTEST_LEN(bp, 30) && GET_U_1(bp + 11) == 1 &&
((njoin = GET_BE_U_2(bp + 20)) + GET_BE_U_2(bp + 22)) == 1) {
u_int hold;
ND_PRINT(" RPF %s ", GET_IPADDR_STRING(bp));
hold = GET_BE_U_2(bp + 6);
if (hold != 180) {
ND_PRINT("Hold ");
unsigned_relts_print(ndo, hold);
}
ND_PRINT("%s (%s/%u, %s", njoin ? "Join" : "Prune",
GET_IPADDR_STRING(bp + 26), GET_U_1(bp + 25) & 0x3f,
GET_IPADDR_STRING(bp + 12));
if (GET_BE_U_4(bp + 16) != 0xffffffff)
ND_PRINT("/%s", GET_IPADDR_STRING(bp + 16));
ND_PRINT(") %s%s %s",
(GET_U_1(bp + 24) & 0x01) ? "Sparse" : "Dense",
(GET_U_1(bp + 25) & 0x80) ? " WC" : "",
(GET_U_1(bp + 25) & 0x40) ? "RP" : "SPT");
return;
}
if (len < sizeof(nd_ipv4))
goto trunc;
ND_TCHECK_LEN(bp, sizeof(nd_ipv4));
if (ndo->ndo_vflag > 1)
ND_PRINT("\n");
ND_PRINT(" Upstream Nbr: %s", GET_IPADDR_STRING(bp));
bp += 4;
len -= 4;
if (len < 4)
goto trunc;
ND_TCHECK_2(bp + 2);
if (ndo->ndo_vflag > 1)
ND_PRINT("\n");
ND_PRINT(" Hold time: ");
unsigned_relts_print(ndo, GET_BE_U_2(bp + 2));
if (ndo->ndo_vflag < 2)
return;
bp += 4;
len -= 4;
if (len < 4)
goto trunc;
ND_TCHECK_4(bp);
ngroups = GET_U_1(bp + 3);
bp += 4;
len -= 4;
while (ngroups != 0) {
/*
* XXX - does the address have length "addrlen" and the
* mask length "maddrlen"?
*/
if (len < 4)
goto trunc;
ND_TCHECK_LEN(bp, sizeof(nd_ipv4));
ND_PRINT("\n\tGroup: %s", GET_IPADDR_STRING(bp));
bp += 4;
len -= 4;
if (len < 4)
goto trunc;
ND_TCHECK_LEN(bp, sizeof(nd_ipv4));
if (GET_BE_U_4(bp) != 0xffffffff)
ND_PRINT("/%s", GET_IPADDR_STRING(bp));
bp += 4;
len -= 4;
if (len < 4)
goto trunc;
ND_TCHECK_4(bp);
njoin = GET_BE_U_2(bp);
nprune = GET_BE_U_2(bp + 2);
ND_PRINT(" joined: %u pruned: %u", njoin, nprune);
bp += 4;
len -= 4;
for (njp = 0; njp < (njoin + nprune); njp++) {
const char *type;
if (njp < njoin)
type = "Join ";
else
type = "Prune";
if (len < 6)
goto trunc;
ND_TCHECK_6(bp);
ND_PRINT("\n\t%s %s%s%s%s/%u", type,
(GET_U_1(bp) & 0x01) ? "Sparse " : "Dense ",
(GET_U_1(bp + 1) & 0x80) ? "WC " : "",
(GET_U_1(bp + 1) & 0x40) ? "RP " : "SPT ",
GET_IPADDR_STRING(bp + 2),
GET_U_1(bp + 1) & 0x3f);
bp += 6;
len -= 6;
}
ngroups--;
}
return;
trunc:
nd_print_trunc(ndo);
return;
}
void
pimv1_print(netdissect_options *ndo,
const u_char *bp, u_int len)
{
u_char type;
ndo->ndo_protocol = "pimv1";
ND_TCHECK_1(bp + 1);
type = GET_U_1(bp + 1);
ND_PRINT(" %s", tok2str(pimv1_type_str, "[type %u]", type));
switch (type) {
case PIMV1_TYPE_QUERY:
if (ND_TTEST_1(bp + 8)) {
switch (GET_U_1(bp + 8) >> 4) {
case 0:
ND_PRINT(" Dense-mode");
break;
case 1:
ND_PRINT(" Sparse-mode");
break;
case 2:
ND_PRINT(" Sparse-Dense-mode");
break;
default:
ND_PRINT(" mode-%u", GET_U_1(bp + 8) >> 4);
break;
}
}
if (ndo->ndo_vflag) {
ND_TCHECK_2(bp + 10);
ND_PRINT(" (Hold-time ");
unsigned_relts_print(ndo, GET_BE_U_2(bp + 10));
ND_PRINT(")");
}
break;
case PIMV1_TYPE_REGISTER:
ND_TCHECK_LEN(bp + 8, 20); /* ip header */
ND_PRINT(" for %s > %s", GET_IPADDR_STRING(bp + 20),
GET_IPADDR_STRING(bp + 24));
break;
case PIMV1_TYPE_REGISTER_STOP:
ND_TCHECK_LEN(bp + 12, sizeof(nd_ipv4));
ND_PRINT(" for %s > %s", GET_IPADDR_STRING(bp + 8),
GET_IPADDR_STRING(bp + 12));
break;
case PIMV1_TYPE_RP_REACHABILITY:
if (ndo->ndo_vflag) {
ND_TCHECK_2(bp + 22);
ND_PRINT(" group %s", GET_IPADDR_STRING(bp + 8));
if (GET_BE_U_4(bp + 12) != 0xffffffff)
ND_PRINT("/%s", GET_IPADDR_STRING(bp + 12));
ND_PRINT(" RP %s hold ", GET_IPADDR_STRING(bp + 16));
unsigned_relts_print(ndo, GET_BE_U_2(bp + 22));
}
break;
case PIMV1_TYPE_ASSERT:
ND_TCHECK_LEN(bp + 16, sizeof(nd_ipv4));
ND_PRINT(" for %s > %s", GET_IPADDR_STRING(bp + 16),
GET_IPADDR_STRING(bp + 8));
if (GET_BE_U_4(bp + 12) != 0xffffffff)
ND_PRINT("/%s", GET_IPADDR_STRING(bp + 12));
ND_TCHECK_4(bp + 24);
ND_PRINT(" %s pref %u metric %u",
(GET_U_1(bp + 20) & 0x80) ? "RP-tree" : "SPT",
GET_BE_U_4(bp + 20) & 0x7fffffff,
GET_BE_U_4(bp + 24));
break;
case PIMV1_TYPE_JOIN_PRUNE:
case PIMV1_TYPE_GRAFT:
case PIMV1_TYPE_GRAFT_ACK:
if (ndo->ndo_vflag) {
if (len < 8)
goto trunc;
pimv1_join_prune_print(ndo, bp + 8, len - 8);
}
break;
}
ND_TCHECK_1(bp + 4);
if ((GET_U_1(bp + 4) >> 4) != 1)
ND_PRINT(" [v%u]", GET_U_1(bp + 4) >> 4);
return;
trunc:
nd_print_trunc(ndo);
return;
}
/*
* auto-RP is a cisco protocol, documented at
* ftp://ftpeng.cisco.com/ipmulticast/specs/pim-autorp-spec01.txt
*
* This implements version 1+, dated Sept 9, 1998.
*/
void
cisco_autorp_print(netdissect_options *ndo,
const u_char *bp, u_int len)
{
u_int type;
u_int numrps;
u_int hold;
ndo->ndo_protocol = "cisco_autorp";
if (len < 8)
goto trunc;
ND_TCHECK_1(bp);
ND_PRINT(" auto-rp ");
type = GET_U_1(bp);
switch (type) {
case 0x11:
ND_PRINT("candidate-advert");
break;
case 0x12:
ND_PRINT("mapping");
break;
default:
ND_PRINT("type-0x%02x", type);
break;
}
ND_TCHECK_1(bp + 1);
numrps = GET_U_1(bp + 1);
ND_TCHECK_2(bp + 2);
ND_PRINT(" Hold ");
hold = GET_BE_U_2(bp + 2);
if (hold)
unsigned_relts_print(ndo, GET_BE_U_2(bp + 2));
else
ND_PRINT("FOREVER");
/* Next 4 bytes are reserved. */
bp += 8; len -= 8;
/*XXX skip unless -v? */
/*
* Rest of packet:
* numrps entries of the form:
* 32 bits: RP
* 6 bits: reserved
* 2 bits: PIM version supported, bit 0 is "supports v1", 1 is "v2".
* 8 bits: # of entries for this RP
* each entry: 7 bits: reserved, 1 bit: negative,
* 8 bits: mask 32 bits: source
* lather, rinse, repeat.
*/
while (numrps != 0) {
u_int nentries;
char s;
if (len < 4)
goto trunc;
ND_TCHECK_4(bp);
ND_PRINT(" RP %s", GET_IPADDR_STRING(bp));
bp += 4;
len -= 4;
if (len < 1)
goto trunc;
ND_TCHECK_1(bp);
switch (GET_U_1(bp) & 0x3) {
case 0: ND_PRINT(" PIMv?");
break;
case 1: ND_PRINT(" PIMv1");
break;
case 2: ND_PRINT(" PIMv2");
break;
case 3: ND_PRINT(" PIMv1+2");
break;
}
if (GET_U_1(bp) & 0xfc)
ND_PRINT(" [rsvd=0x%02x]", GET_U_1(bp) & 0xfc);
bp += 1;
len -= 1;
if (len < 1)
goto trunc;
ND_TCHECK_1(bp);
nentries = GET_U_1(bp);
bp += 1;
len -= 1;
s = ' ';
while (nentries != 0) {
if (len < 6)
goto trunc;
ND_TCHECK_6(bp);
ND_PRINT("%c%s%s/%u", s, GET_U_1(bp) & 1 ? "!" : "",
GET_IPADDR_STRING(bp + 2), GET_U_1(bp + 1));
if (GET_U_1(bp) & 0x02) {
ND_PRINT(" bidir");
}
if (GET_U_1(bp) & 0xfc) {
ND_PRINT("[rsvd=0x%02x]", GET_U_1(bp) & 0xfc);
}
s = ',';
bp += 6; len -= 6;
nentries--;
}
numrps--;
}
return;
trunc:
nd_print_trunc(ndo);
return;
}
void
pim_print(netdissect_options *ndo,
const u_char *bp, u_int len, const u_char *bp2)
{
const struct pim *pim = (const struct pim *)bp;
uint8_t pim_typever;
ndo->ndo_protocol = "pim";
#ifdef notyet /* currently we see only version and type */
ND_TCHECK_1(pim->pim_rsv);
#endif
ND_TCHECK_1(pim->pim_typever);
pim_typever = GET_U_1(pim->pim_typever);
switch (PIM_VER(pim_typever)) {
case 2:
if (!ndo->ndo_vflag) {
ND_PRINT("PIMv%u, %s, length %u",
PIM_VER(pim_typever),
tok2str(pimv2_type_values,"Unknown Type",PIM_TYPE(pim_typever)),
len);
return;
} else {
ND_PRINT("PIMv%u, length %u\n\t%s",
PIM_VER(pim_typever),
len,
tok2str(pimv2_type_values,"Unknown Type",PIM_TYPE(pim_typever)));
pimv2_print(ndo, bp, len, bp2);
}
break;
default:
ND_PRINT("PIMv%u, length %u",
PIM_VER(pim_typever),
len);
break;
}
return;
trunc:
nd_print_trunc(ndo);
return;
}
/*
* PIMv2 uses encoded address representations.
*
* The last PIM-SM I-D before RFC2117 was published specified the
* following representation for unicast addresses. However, RFC2117
* specified no encoding for unicast addresses with the unicast
* address length specified in the header. Therefore, we have to
* guess which encoding is being used (Cisco's PIMv2 implementation
* uses the non-RFC encoding). RFC2117 turns a previously "Reserved"
* field into a 'unicast-address-length-in-bytes' field. We guess
* that it's the draft encoding if this reserved field is zero.
*
* RFC2362 goes back to the encoded format, and calls the addr length
* field "reserved" again.
*
* The first byte is the address family, from:
*
* 0 Reserved
* 1 IP (IP version 4)
* 2 IP6 (IP version 6)
* 3 NSAP
* 4 HDLC (8-bit multidrop)
* 5 BBN 1822
* 6 802 (includes all 802 media plus Ethernet "canonical format")
* 7 E.163
* 8 E.164 (SMDS, Frame Relay, ATM)
* 9 F.69 (Telex)
* 10 X.121 (X.25, Frame Relay)
* 11 IPX
* 12 Appletalk
* 13 Decnet IV
* 14 Banyan Vines
* 15 E.164 with NSAP format subaddress
*
* In addition, the second byte is an "Encoding". 0 is the default
* encoding for the address family, and no other encodings are currently
* specified.
*
*/
enum pimv2_addrtype {
pimv2_unicast, pimv2_group, pimv2_source
};
/* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Addr Family | Encoding Type | Unicast Address |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+++++++
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Addr Family | Encoding Type | Reserved | Mask Len |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Group multicast Address |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Addr Family | Encoding Type | Rsrvd |S|W|R| Mask Len |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Source Address |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
static int
pimv2_addr_print(netdissect_options *ndo,
const u_char *bp, u_int len, enum pimv2_addrtype at,
u_int addr_len, int silent)
{
u_int af;
int hdrlen;
if (addr_len == 0) {
if (len < 2)
goto trunc;
ND_TCHECK_1(bp + 1);
switch (GET_U_1(bp)) {
case 1:
af = AF_INET;
addr_len = (u_int)sizeof(nd_ipv4);
break;
case 2:
af = AF_INET6;
addr_len = (u_int)sizeof(nd_ipv6);
break;
default:
return -1;
}
if (GET_U_1(bp + 1) != 0)
return -1;
hdrlen = 2;
} else {
switch (addr_len) {
case sizeof(nd_ipv4):
af = AF_INET;
break;
case sizeof(nd_ipv6):
af = AF_INET6;
break;
default:
return -1;
break;
}
hdrlen = 0;
}
bp += hdrlen;
len -= hdrlen;
switch (at) {
case pimv2_unicast:
if (len < addr_len)
goto trunc;
ND_TCHECK_LEN(bp, addr_len);
if (af == AF_INET) {
if (!silent)
ND_PRINT("%s", GET_IPADDR_STRING(bp));
}
else if (af == AF_INET6) {
if (!silent)
ND_PRINT("%s", GET_IP6ADDR_STRING(bp));
}
return hdrlen + addr_len;
case pimv2_group:
case pimv2_source:
if (len < addr_len + 2)
goto trunc;
ND_TCHECK_LEN(bp, addr_len + 2);
if (af == AF_INET) {
if (!silent) {
ND_PRINT("%s", GET_IPADDR_STRING(bp + 2));
if (GET_U_1(bp + 1) != 32)
ND_PRINT("/%u", GET_U_1(bp + 1));
}
}
else if (af == AF_INET6) {
if (!silent) {
ND_PRINT("%s", GET_IP6ADDR_STRING(bp + 2));
if (GET_U_1(bp + 1) != 128)
ND_PRINT("/%u", GET_U_1(bp + 1));
}
}
if (GET_U_1(bp) && !silent) {
if (at == pimv2_group) {
ND_PRINT("(0x%02x)", GET_U_1(bp));
} else {
ND_PRINT("(%s%s%s",
GET_U_1(bp) & 0x04 ? "S" : "",
GET_U_1(bp) & 0x02 ? "W" : "",
GET_U_1(bp) & 0x01 ? "R" : "");
if (GET_U_1(bp) & 0xf8) {
ND_PRINT("+0x%02x",
GET_U_1(bp) & 0xf8);
}
ND_PRINT(")");
}
}
return hdrlen + 2 + addr_len;
default:
return -1;
}
trunc:
return -1;
}
enum checksum_status {
CORRECT,
INCORRECT,
UNVERIFIED
};
static enum checksum_status
pimv2_check_checksum(netdissect_options *ndo, const u_char *bp,
const u_char *bp2, u_int len)
{
const struct ip *ip;
u_int cksum;
if (!ND_TTEST_LEN(bp, len)) {
/* We don't have all the data. */
return (UNVERIFIED);
}
ip = (const struct ip *)bp2;
if (IP_V(ip) == 4) {
struct cksum_vec vec[1];
vec[0].ptr = bp;
vec[0].len = len;
cksum = in_cksum(vec, 1);
return (cksum ? INCORRECT : CORRECT);
} else if (IP_V(ip) == 6) {
const struct ip6_hdr *ip6;
ip6 = (const struct ip6_hdr *)bp2;
cksum = nextproto6_cksum(ndo, ip6, bp, len, len, IPPROTO_PIM);
return (cksum ? INCORRECT : CORRECT);
} else {
return (UNVERIFIED);
}
}
static void
pimv2_print(netdissect_options *ndo,
const u_char *bp, u_int len, const u_char *bp2)
{
const struct pim *pim = (const struct pim *)bp;
int advance;
int subtype;
enum checksum_status cksum_status;
u_int pim_typever;
u_int pimv2_addr_len;
ndo->ndo_protocol = "pimv2";
if (len < 2) {
ND_PRINT("[length %u < 2]", len);
nd_print_invalid(ndo);
return;
}
ND_TCHECK_1(pim->pim_rsv);
pim_typever = GET_U_1(pim->pim_typever);
/* RFC5015 allocates the high 4 bits of pim_rsv for "subtype". */
pimv2_addr_len = GET_U_1(pim->pim_rsv) & 0x0f;
if (pimv2_addr_len != 0)
ND_PRINT(", RFC2117-encoding");
if (len < 4) {
ND_PRINT("[length %u < 4]", len);
nd_print_invalid(ndo);
return;
}
ND_TCHECK_2(pim->pim_cksum);
ND_PRINT(", cksum 0x%04x ", GET_BE_U_2(pim->pim_cksum));
if (GET_BE_U_2(pim->pim_cksum) == 0) {
ND_PRINT("(unverified)");
} else {
if (PIM_TYPE(pim_typever) == PIMV2_TYPE_REGISTER) {
/*
* The checksum only covers the packet header,
* not the encapsulated packet.
*/
cksum_status = pimv2_check_checksum(ndo, bp, bp2, 8);
if (cksum_status == INCORRECT) {
/*
* To quote RFC 4601, "For interoperability
* reasons, a message carrying a checksum
* calculated over the entire PIM Register
* message should also be accepted."
*/
cksum_status = pimv2_check_checksum(ndo, bp, bp2, len);
}
} else {
/*
* The checksum covers the entire packet.
*/
cksum_status = pimv2_check_checksum(ndo, bp, bp2, len);
}
switch (cksum_status) {
case CORRECT:
ND_PRINT("(correct)");
break;
case INCORRECT:
ND_PRINT("(incorrect)");
break;
case UNVERIFIED:
ND_PRINT("(unverified)");
break;
}
}
bp += 4;
len -= 4;
switch (PIM_TYPE(pim_typever)) {
case PIMV2_TYPE_HELLO:
{
uint16_t otype, olen;
while (len > 0) {
if (len < 4)
goto trunc;
ND_TCHECK_4(bp);
otype = GET_BE_U_2(bp);
olen = GET_BE_U_2(bp + 2);
ND_PRINT("\n\t %s Option (%u), length %u, Value: ",
tok2str(pimv2_hello_option_values, "Unknown", otype),
otype,
olen);
bp += 4;
len -= 4;
if (len < olen)
goto trunc;
ND_TCHECK_LEN(bp, olen);
switch (otype) {
case PIMV2_HELLO_OPTION_HOLDTIME:
if (olen != 2) {
ND_PRINT("[option length %u != 2]", olen);
nd_print_invalid(ndo);
return;
} else {
unsigned_relts_print(ndo,
GET_BE_U_2(bp));
}
break;
case PIMV2_HELLO_OPTION_LANPRUNEDELAY:
if (olen != 4) {
ND_PRINT("[option length %u != 4]", olen);
nd_print_invalid(ndo);
return;
} else {
char t_bit;
uint16_t lan_delay, override_interval;
lan_delay = GET_BE_U_2(bp);
override_interval = GET_BE_U_2(bp + 2);
t_bit = (lan_delay & 0x8000)? 1 : 0;
lan_delay &= ~0x8000;
ND_PRINT("\n\t T-bit=%u, LAN delay %ums, Override interval %ums",
t_bit, lan_delay, override_interval);
}
break;
case PIMV2_HELLO_OPTION_DR_PRIORITY_OLD:
case PIMV2_HELLO_OPTION_DR_PRIORITY:
switch (olen) {
case 0:
ND_PRINT("Bi-Directional Capability (Old)");
break;
case 4:
ND_PRINT("%u", GET_BE_U_4(bp));
break;
default:
ND_PRINT("[option length %u != 4]", olen);
nd_print_invalid(ndo);
return;
break;
}
break;
case PIMV2_HELLO_OPTION_GENID:
if (olen != 4) {
ND_PRINT("[option length %u != 4]", olen);
nd_print_invalid(ndo);
return;
} else {
ND_PRINT("0x%08x", GET_BE_U_4(bp));
}
break;
case PIMV2_HELLO_OPTION_REFRESH_CAP:
if (olen != 4) {
ND_PRINT("[option length %u != 4]", olen);
nd_print_invalid(ndo);
return;
} else {
ND_PRINT("v%u", GET_U_1(bp));
if (GET_U_1(bp + 1) != 0) {
ND_PRINT(", interval ");
unsigned_relts_print(ndo,
GET_U_1(bp + 1));
}
if (GET_BE_U_2(bp + 2) != 0) {
ND_PRINT(" ?0x%04x?",
GET_BE_U_2(bp + 2));
}
}
break;
case PIMV2_HELLO_OPTION_BIDIR_CAP:
break;
case PIMV2_HELLO_OPTION_ADDRESS_LIST_OLD:
case PIMV2_HELLO_OPTION_ADDRESS_LIST:
if (ndo->ndo_vflag > 1) {
const u_char *ptr = bp;
u_int plen = len;
while (ptr < (bp+olen)) {
ND_PRINT("\n\t ");
advance = pimv2_addr_print(ndo, ptr, plen, pimv2_unicast, pimv2_addr_len, 0);
if (advance < 0)
goto trunc;
ptr += advance;
plen -= advance;
}
}
break;
default:
if (ndo->ndo_vflag <= 1)
print_unknown_data(ndo, bp, "\n\t ", olen);
break;
}
/* do we want to see an additionally hexdump ? */
if (ndo->ndo_vflag> 1)
print_unknown_data(ndo, bp, "\n\t ", olen);
bp += olen;
len -= olen;
}
break;
}
case PIMV2_TYPE_REGISTER:
{
const struct ip *ip;
if (len < 4)
goto trunc;
ND_TCHECK_LEN(bp, PIMV2_REGISTER_FLAG_LEN);
ND_PRINT(", Flags [ %s ]\n\t",
tok2str(pimv2_register_flag_values,
"none",
GET_BE_U_4(bp)));
bp += 4; len -= 4;
/* encapsulated multicast packet */
if (len == 0)
goto trunc;
ip = (const struct ip *)bp;
ND_TCHECK_1(ip->ip_vhl);
switch (IP_V(ip)) {
case 0: /* Null header */
ND_TCHECK_4(ip->ip_dst);
ND_PRINT("IP-Null-header %s > %s",
GET_IPADDR_STRING(ip->ip_src),
GET_IPADDR_STRING(ip->ip_dst));
break;
case 4: /* IPv4 */
ip_print(ndo, bp, len);
break;
case 6: /* IPv6 */
ip6_print(ndo, bp, len);
break;
default:
ND_PRINT("IP ver %u", IP_V(ip));
break;
}
break;
}
case PIMV2_TYPE_REGISTER_STOP:
ND_PRINT(" group=");
if ((advance = pimv2_addr_print(ndo, bp, len, pimv2_group, pimv2_addr_len, 0)) < 0)
goto trunc;
bp += advance; len -= advance;
ND_PRINT(" source=");
if ((advance = pimv2_addr_print(ndo, bp, len, pimv2_unicast, pimv2_addr_len, 0)) < 0)
goto trunc;
bp += advance; len -= advance;
break;
case PIMV2_TYPE_JOIN_PRUNE:
case PIMV2_TYPE_GRAFT:
case PIMV2_TYPE_GRAFT_ACK:
/*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |PIM Ver| Type | Addr length | Checksum |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Unicast-Upstream Neighbor Address |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Reserved | Num groups | Holdtime |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Encoded-Multicast Group Address-1 |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Number of Joined Sources | Number of Pruned Sources |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Encoded-Joined Source Address-1 |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | . |
* | . |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Encoded-Joined Source Address-n |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Encoded-Pruned Source Address-1 |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+