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mtrace.c
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mtrace.c
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/*
* mtrace.c
*
* This tool traces the branch of a multicast tree from a source to a
* receiver for a particular multicast group and gives statistics
* about packet rate and loss for each hop along the path. It can
* usually be invoked just as
*
* mtrace source
*
* to trace the route from that source to the local host for a default
* group when only the route is desired and not group-specific packet
* counts. See the usage line for more complex forms.
*
*
* Released 4 Apr 1995. This program was adapted by Steve Casner
* (USC/ISI) from a prototype written by Ajit Thyagarajan (UDel and
* Xerox PARC). It attempts to parallel in command syntax and output
* format the unicast traceroute program written by Van Jacobson (LBL)
* for the parts where that makes sense.
*
* Copyright (c) 1998-2001.
* The University of Southern California/Information Sciences Institute.
* All rights reserved.
*
* 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.
* 3. Neither the name of the project 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 BY THE PROJECT AND CONTRIBUTORS ``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 PROJECT OR CONTRIBUTORS 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.
*/
#include "defs.h"
#include <arpa/inet.h>
#include <ctype.h>
#include <err.h>
#include <ifaddrs.h>
#include <memory.h>
#include <netdb.h>
#include <poll.h>
#include <stdarg.h>
#include <string.h>
#include <sys/ioctl.h>
#ifdef SUNOS5
#include <sys/systeminfo.h>
#endif
#include <sys/time.h>
#define DEFAULT_TIMEOUT 3 /* How long to wait before retrying requests */
#define DEFAULT_RETRIES 3 /* How many times to try */
#define MAXHOPS UNREACHABLE /* Don't need more hops than max metric */
#define UNICAST_TTL 255 /* TTL for unicast response */
#define MULTICAST_TTL1 64 /* Default TTL for multicast query/response */
#define MULTICAST_TTL_INC 32 /* TTL increment for increase after timeout */
#define MULTICAST_TTL_MAX 192 /* Maximum TTL allowed (protect low-BW links */
struct resp_buf {
u_long qtime; /* Time query was issued */
u_long rtime; /* Time response was received */
int len; /* Number of reports or length of data */
struct igmp igmp; /* IGMP header */
union {
struct {
struct tr_query q; /* Query/response header */
struct tr_resp r[MAXHOPS]; /* Per-hop reports */
} t;
char d[MAX_DVMRP_DATA_LEN]; /* Neighbor data */
} u;
} base, incr[2];
#define qhdr u.t.q
#define resps u.t.r
#define ndata u.d
char names[MAXHOPS][40];
int reset[MAXHOPS]; /* To get around 3.4 bug, ... */
int swaps[MAXHOPS]; /* To get around 3.6 bug, ... */
int timeout = DEFAULT_TIMEOUT;
int nqueries = DEFAULT_RETRIES;
int numeric = FALSE;
int debug = 0;
int passive = FALSE;
int multicast = FALSE;
int statint = 10;
int verbose = 0;
u_int32_t defgrp; /* Default group if not specified */
u_int32_t query_cast; /* All routers multicast addr */
u_int32_t resp_cast; /* Mtrace response multicast addr */
u_int32_t lcl_addr = 0; /* This host address, in NET order */
u_int32_t dst_netmask; /* netmask to go with qdst */
/*
* Query/response parameters, all initialized to zero and set later
* to default values or from options.
*/
u_int32_t qsrc = 0; /* Source address in the query */
u_int32_t qgrp = 0; /* Group address in the query */
u_int32_t qdst = 0; /* Destination (receiver) address in query */
u_char qno = 0; /* Max number of hops to query */
u_int32_t raddr = 0; /* Address where response should be sent */
int qttl = 0; /* TTL for the query packet */
u_char rttl = 0; /* TTL for the response packet */
u_int32_t gwy = 0; /* User-supplied last-hop router address */
u_int32_t tdst = 0; /* Address where trace is sent (last-hop) */
vifi_t numvifs; /* to keep loader happy */
/* (see kern.c) */
char * inet_name(u_int32_t addr);
u_int32_t host_addr(char *name);
/* u_int is promoted u_char */
char * proto_type(u_int type);
char * flag_type(u_int type);
u_int32_t get_netmask(int s, u_int32_t dst);
int get_ttl(struct resp_buf *buf);
int t_diff(u_long a, u_long b);
u_long fixtime(u_long time);
int send_recv(u_int32_t dst, int type, int code,
int tries, struct resp_buf *save);
char * print_host(u_int32_t addr);
char * print_host2(u_int32_t addr1, u_int32_t addr2);
void print_trace(int index, struct resp_buf *buf);
int what_kind(struct resp_buf *buf, char *why);
char * scale(int *hop);
void stat_line(struct tr_resp *r, struct tr_resp *s,
int have_next, int *res);
void fixup_stats(struct resp_buf *base,
struct resp_buf *prev, struct resp_buf *new);
int print_stats(struct resp_buf *base,
struct resp_buf *prev, struct resp_buf *new);
void check_vif_state(void);
u_long byteswap(u_long v);
char *inet_name(u_int32_t addr)
{
struct hostent *e;
e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET);
return e ? e->h_name : "?";
}
u_int32_t host_addr(char *name)
{
struct hostent *e = (struct hostent *)0;
u_int32_t addr;
int i, dots = 3;
char buf[40];
char *ip = name;
char *op = buf;
/*
* Undo BSD's favor -- take fewer than 4 octets as net/subnet address
* if the name is all numeric.
*/
for (i = sizeof(buf) - 7; i > 0; --i) {
if (*ip == '.') --dots;
else if (*ip == '\0') break;
else if (!isdigit((int)*ip)) dots = 0; /* Not numeric, don't add zeroes */
*op++ = *ip++;
}
for (i = 0; i < dots; ++i) {
*op++ = '.';
*op++ = '0';
}
*op = '\0';
if (dots <= 0) e = gethostbyname(name);
if (e) memcpy((char *)&addr, e->h_addr_list[0], e->h_length);
else {
addr = inet_addr(buf);
if (addr == INADDR_NONE) {
addr = 0;
printf("Could not parse %s as host name or address\n", name);
}
}
return addr;
}
char *proto_type(u_int type)
{
static char buf[80];
switch (type) {
case PROTO_DVMRP:
return ("DVMRP");
case PROTO_MOSPF:
return ("MOSPF");
case PROTO_PIM:
return ("PIM");
case PROTO_CBT:
return ("CBT");
default:
(void) snprintf(buf, sizeof buf, "Unknown protocol code %d", type);
return (buf);
}
}
char *flag_type(u_int type)
{
static char buf[80];
switch (type) {
case TR_NO_ERR:
return ("");
case TR_WRONG_IF:
return ("Wrong interface");
case TR_PRUNED:
return ("Prune sent upstream");
case TR_OPRUNED:
return ("Output pruned");
case TR_SCOPED:
return ("Hit scope boundary");
case TR_NO_RTE:
return ("No route");
case TR_OLD_ROUTER:
return ("Next router no mtrace");
case TR_NO_FWD:
return ("Not forwarding");
case TR_NO_SPACE:
return ("No space in packet");
default:
(void) snprintf(buf, sizeof buf, "Unknown error code %d", type);
return (buf);
}
}
/*
* If destination is on a local net, get the netmask, else set the
* netmask to all ones. There are two side effects: if the local
* address was not explicitly set, and if the destination is on a
* local net, use that one; in either case, verify that the local
* address is valid.
*/
u_int32_t get_netmask(int UNUSED s, u_int32_t dst)
{
u_int32_t if_addr, if_mask;
u_int32_t retval = 0xFFFFFFFF;
int found = FALSE;
struct ifaddrs *ifap, *ifa;
if (getifaddrs(&ifap) != 0) {
perror("getifaddrs");
return (retval);
}
for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
if (!ifa->ifa_addr || ifa->ifa_addr->sa_family != AF_INET)
continue;
if_addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr;
if_mask = ((struct sockaddr_in *)ifa->ifa_netmask)->sin_addr.s_addr;
if ((dst & if_mask) == (if_addr & if_mask)) {
retval = if_mask;
if (lcl_addr == 0)
lcl_addr = if_addr;
}
if (lcl_addr == if_addr)
found = TRUE;
}
if (!found && lcl_addr != 0) {
printf("Interface address is not valid\n");
exit(1);
}
freeifaddrs(ifap);
return (retval);
}
int get_ttl(struct resp_buf *buf)
{
int rno;
struct tr_resp *b;
u_int ttl;
if (buf && (rno = buf->len) > 0) {
b = buf->resps + rno - 1;
ttl = b->tr_fttl;
while (--rno > 0) {
--b;
if (ttl < b->tr_fttl) ttl = b->tr_fttl;
else ++ttl;
}
ttl += MULTICAST_TTL_INC;
if (ttl < MULTICAST_TTL1) ttl = MULTICAST_TTL1;
if (ttl > MULTICAST_TTL_MAX) ttl = MULTICAST_TTL_MAX;
return (ttl);
} else return(MULTICAST_TTL1);
}
/*
* Calculate the difference between two 32-bit NTP timestamps and return
* the result in milliseconds.
*/
int t_diff(u_long a, u_long b)
{
int d = a - b;
return ((d * 125) >> 13);
}
/*
* Fixup for incorrect time format in 3.3 mrouted.
* This is possible because (JAN_1970 mod 64K) is quite close to 32K,
* so correct and incorrect times will be far apart.
*/
u_long fixtime(u_long time)
{
if (abs((int)(time-base.qtime)) > 0x3FFFFFFF)
time = ((time & 0xFFFF0000) + (JAN_1970 << 16)) +
((time & 0xFFFF) << 14) / 15625;
return (time);
}
/*
* Swap bytes for poor little-endian machines that don't byte-swap
*/
u_long byteswap(u_long v)
{
return ((v << 24) | ((v & 0xff00) << 8) |
((v >> 8) & 0xff00) | (v >> 24));
}
int send_recv(u_int32_t dst, int type, int code, int tries, struct resp_buf *save)
{
struct timeval tq, tr, tv;
struct ip *ip;
struct igmp *igmp;
struct tr_query *query, *rquery;
size_t ipdatalen, iphdrlen;
u_int32_t local, group;
int datalen;
struct pollfd pfd[1];
int count, len, i;
size_t igmpdatalen;
ssize_t recvlen;
socklen_t dummy = 0;
if (type == IGMP_MTRACE) {
group = qgrp;
datalen = sizeof(struct tr_query);
} else {
group = htonl(MROUTED_LEVEL);
datalen = 0;
}
if (IN_MULTICAST(ntohl(dst))) local = lcl_addr;
else local = INADDR_ANY;
/*
* If the reply address was not explicitly specified, start off
* with the unicast address of this host. Then, if there is no
* response after trying half the tries with unicast, switch to
* the standard multicast reply address. If the TTL was also not
* specified, set a multicast TTL and if needed increase it for the
* last quarter of the tries.
*/
query = (struct tr_query *)(send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN);
query->tr_raddr = raddr ? raddr : multicast ? resp_cast : lcl_addr;
query->tr_rttl = rttl ? rttl :
IN_MULTICAST(ntohl(query->tr_raddr)) ? get_ttl(save) : UNICAST_TTL;
query->tr_src = qsrc;
query->tr_dst = qdst;
for (i = tries ; i > 0; --i) {
if (tries == nqueries && raddr == 0) {
if (i == ((nqueries + 1) >> 1)) {
query->tr_raddr = resp_cast;
if (rttl == 0) query->tr_rttl = get_ttl(save);
}
if (i <= ((nqueries + 3) >> 2) && rttl == 0) {
query->tr_rttl += MULTICAST_TTL_INC;
if (query->tr_rttl > MULTICAST_TTL_MAX)
query->tr_rttl = MULTICAST_TTL_MAX;
}
}
/*
* Change the qid for each request sent to avoid being confused
* by duplicate responses
*/
#ifdef SYSV
query->tr_qid = ((u_int32_t)lrand48() >> 8);
#else
query->tr_qid = ((u_int32_t)random() >> 8);
#endif
/*
* Set timer to calculate delays, then send query
*/
gettimeofday(&tq, 0);
send_igmp(local, dst, type, code, group, datalen);
/*
* Wait for response, discarding false alarms
*/
pfd[0].fd = igmp_socket;
pfd[0].events = POLLIN;
while (TRUE) {
gettimeofday(&tv, 0);
tv.tv_sec = tq.tv_sec + timeout - tv.tv_sec;
tv.tv_usec = tq.tv_usec - tv.tv_usec;
if (tv.tv_usec < 0) tv.tv_usec += 1000000L, --tv.tv_sec;
if (tv.tv_sec < 0) tv.tv_sec = tv.tv_usec = 0;
count = poll(pfd, 1, tv.tv_sec * 1000);
if (count < 0) {
if (errno != EINTR) perror("poll");
continue;
} else if (count == 0) {
printf("* ");
fflush(stdout);
break;
}
gettimeofday(&tr, 0);
recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
0, (struct sockaddr *)0, &dummy);
if (recvlen <= 0) {
if (recvlen && errno != EINTR) perror("recvfrom");
continue;
}
if ((size_t)recvlen < sizeof(struct ip)) {
fprintf(stderr, "packet too short (%zd bytes) for IP header", recvlen);
continue;
}
ip = (struct ip *) recv_buf;
if (ip->ip_p == 0) /* ignore cache creation requests */
continue;
iphdrlen = ip->ip_hl << 2;
ipdatalen = ntohs(ip->ip_len) - iphdrlen;
if (iphdrlen + ipdatalen != (size_t)recvlen) {
fprintf(stderr, "packet shorter (%zd bytes) than hdr+data len (%zu+%zu)\n",
recvlen, iphdrlen, ipdatalen);
continue;
}
igmp = (struct igmp *) (recv_buf + iphdrlen);
if (ipdatalen < IGMP_MINLEN) {
fprintf(stderr,
"IP data field too short (%zu bytes) for IGMP from %s\n",
ipdatalen, inet_fmt(ip->ip_src.s_addr, s1, sizeof(s1)));
continue;
}
igmpdatalen = ipdatalen - IGMP_MINLEN;
switch (igmp->igmp_type) {
case IGMP_DVMRP:
if (igmp->igmp_code != DVMRP_NEIGHBORS2) continue;
len = igmpdatalen;
/*
* Accept DVMRP_NEIGHBORS2 response if it comes from the
* address queried or if that address is one of the local
* addresses in the response.
*/
if (ip->ip_src.s_addr != dst) {
u_int32_t *p = (u_int32_t *)(igmp + 1);
u_int32_t *ep = p + (len >> 2);
while (p < ep) {
u_int32_t laddr = *p++;
int n = ntohl(*p++) & 0xFF;
if (laddr == dst) {
ep = p + 1; /* ensure p < ep after loop */
break;
}
p += n;
}
if (p >= ep) continue;
}
break;
case IGMP_MTRACE: /* For backward compatibility with 3.3 */
case IGMP_MTRACE_RESP:
if (igmpdatalen <= QLEN) continue;
if ((igmpdatalen - QLEN) % RLEN) {
printf("packet with incorrect datalen\n");
continue;
}
/*
* Ignore responses that don't match query.
*/
rquery = (struct tr_query *)(igmp + 1);
if (rquery->tr_qid != query->tr_qid) continue;
if (rquery->tr_src != qsrc) continue;
if (rquery->tr_dst != qdst) continue;
len = (igmpdatalen - QLEN) / RLEN;
/*
* Ignore trace queries passing through this node when
* mtrace is run on an mrouter that is in the path
* (needed only because IGMP_MTRACE is accepted above
* for backward compatibility with multicast release 3.3).
*/
if (igmp->igmp_type == IGMP_MTRACE) {
struct tr_resp *r = (struct tr_resp *)(rquery+1) + len - 1;
u_int32_t smask;
VAL_TO_MASK(smask, r->tr_smask);
if (len < code && (r->tr_inaddr & smask) != (qsrc & smask)
&& r->tr_rmtaddr != 0 && !(r->tr_rflags & 0x80))
continue;
}
/*
* A match, we'll keep this one.
*/
if (len > code) {
fprintf(stderr,
"Num hops received (%d) exceeds request (%d)\n",
len, code);
}
rquery->tr_raddr = query->tr_raddr; /* Insure these are */
rquery->tr_rttl = query->tr_rttl; /* as we sent them */
break;
default:
continue;
}
/*
* Most of the sanity checking done at this point.
* Return this packet we have been waiting for.
*/
if (save) {
save->qtime = ((tq.tv_sec + JAN_1970) << 16) +
(tq.tv_usec << 10) / 15625;
save->rtime = ((tr.tv_sec + JAN_1970) << 16) +
(tr.tv_usec << 10) / 15625;
save->len = len;
bcopy((char *)igmp, (char *)&save->igmp, ipdatalen);
}
return recvlen;
}
}
return 0;
}
/*
* Most of this code is duplicated elsewhere. I'm not sure if
* the duplication is absolutely required or not.
*
* Ideally, this would keep track of ongoing statistics
* collection and print out statistics. (& keep track
* of h-b-h traces and only print the longest) For now,
* it just snoops on what traces it can.
*/
void passive_mode(void)
{
struct timeval tr;
struct ip *ip;
struct igmp *igmp;
struct tr_resp *r;
size_t ipdatalen, iphdrlen, igmpdatalen;
size_t len;
ssize_t recvlen;
socklen_t dummy = 0;
u_int32_t smask;
if (raddr) {
if (IN_MULTICAST(ntohl(raddr))) k_join(raddr, INADDR_ANY);
} else k_join(htonl(0xE0000120), INADDR_ANY);
while (1) {
recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
0, (struct sockaddr *)0, &dummy);
gettimeofday(&tr,0);
if (recvlen <= 0) {
if (recvlen && errno != EINTR) perror("recvfrom");
continue;
}
if ((size_t)recvlen < sizeof(struct ip)) {
fprintf(stderr, "packet too short (%zd bytes) for IP header", recvlen);
continue;
}
ip = (struct ip *) recv_buf;
if (ip->ip_p == 0) /* ignore cache creation requests */
continue;
iphdrlen = ip->ip_hl << 2;
ipdatalen = ntohs(ip->ip_len) - iphdrlen;
if (iphdrlen + ipdatalen != (size_t)recvlen) {
fprintf(stderr, "packet shorter (%zd bytes) than hdr+data len (%zu+%zu)\n",
recvlen, iphdrlen, ipdatalen);
continue;
}
igmp = (struct igmp *) (recv_buf + iphdrlen);
if (ipdatalen < IGMP_MINLEN) {
fprintf(stderr, "IP data field too short (%zu bytes) for IGMP from %s\n",
ipdatalen, inet_fmt(ip->ip_src.s_addr, s1, sizeof(s1)));
continue;
}
igmpdatalen = ipdatalen - IGMP_MINLEN;
switch (igmp->igmp_type) {
case IGMP_MTRACE: /* For backward compatibility with 3.3 */
case IGMP_MTRACE_RESP:
if (igmpdatalen < QLEN) continue;
if ((igmpdatalen - QLEN) % RLEN) {
printf("packet with incorrect datalen\n");
continue;
}
len = (igmpdatalen - QLEN)/RLEN;
break;
default:
continue;
}
base.qtime = ((tr.tv_sec + JAN_1970) << 16) +
(tr.tv_usec << 10) / 15625;
base.rtime = ((tr.tv_sec + JAN_1970) << 16) +
(tr.tv_usec << 10) / 15625;
base.len = len;
bcopy((char *)igmp, (char *)&base.igmp, ipdatalen);
/*
* If the user specified which traces to monitor,
* only accept traces that correspond to the
* request
*/
if ((qsrc != 0 && qsrc != base.qhdr.tr_src) ||
(qdst != 0 && qdst != base.qhdr.tr_dst) ||
(qgrp != 0 && qgrp != igmp->igmp_group.s_addr))
continue;
printf("Mtrace from %s to %s via group %s (mxhop=%d)\n",
inet_fmt(base.qhdr.tr_dst, s1, sizeof(s1)), inet_fmt(base.qhdr.tr_src, s2, sizeof(s2)),
inet_fmt(igmp->igmp_group.s_addr, s3, sizeof(s3)), igmp->igmp_code);
if (len == 0)
continue;
printf(" 0 ");
print_host(base.qhdr.tr_dst);
printf("\n");
print_trace(1, &base);
r = base.resps + base.len - 1;
VAL_TO_MASK(smask, r->tr_smask);
if ((r->tr_inaddr & smask) == (base.qhdr.tr_src & smask)) {
printf("%3d ", -(base.len+1));
print_host(base.qhdr.tr_src);
printf("\n");
} else if (r->tr_rmtaddr != 0) {
printf("%3d ", -(base.len+1));
what_kind(&base, r->tr_rflags == TR_OLD_ROUTER ?
"doesn't support mtrace"
: "is the next hop");
}
printf("\n");
}
}
char *print_host(u_int32_t addr)
{
return print_host2(addr, 0);
}
/*
* On some routers, one interface has a name and the other doesn't.
* We always print the address of the outgoing interface, but can
* sometimes get the name from the incoming interface. This might be
* confusing but should be slightly more helpful than just a "?".
*/
char *print_host2(u_int32_t addr1, u_int32_t addr2)
{
char *name;
if (numeric) {
printf("%s", inet_fmt(addr1, s1, sizeof(s1)));
return ("");
}
name = inet_name(addr1);
if (*name == '?' && *(name + 1) == '\0' && addr2 != 0)
name = inet_name(addr2);
printf("%s (%s)", name, inet_fmt(addr1, s1, sizeof(s1)));
return (name);
}
/*
* Print responses as received (reverse path from dst to src)
*/
void print_trace(int index, struct resp_buf *buf)
{
struct tr_resp *r;
char *name;
int i;
int hop;
char *ms;
i = abs(index);
r = buf->resps + i - 1;
for (; i <= buf->len; ++i, ++r) {
if (index > 0) printf("%3d ", -i);
name = print_host2(r->tr_outaddr, r->tr_inaddr);
printf(" %s thresh^ %d", proto_type(r->tr_rproto), r->tr_fttl);
if (verbose) {
hop = t_diff(fixtime(ntohl(r->tr_qarr)), buf->qtime);
ms = scale(&hop);
printf(" %d%s", hop, ms);
}
printf(" %s\n", flag_type(r->tr_rflags));
memcpy(names[i-1], name, sizeof(names[0]) - 1);
names[i-1][sizeof(names[0])-1] = '\0';
}
}
/*
* See what kind of router is the next hop
*/
int what_kind(struct resp_buf *buf, char *why)
{
u_int32_t smask;
int retval;
int hops = buf->len;
struct tr_resp *r = buf->resps + hops - 1;
u_int32_t next = r->tr_rmtaddr;
retval = send_recv(next, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2, 1, &incr[0]);
print_host(next);
if (retval) {
u_int32_t version = ntohl(incr[0].igmp.igmp_group.s_addr);
u_int32_t *p = (u_int32_t *)incr[0].ndata;
u_int32_t *ep = p + (incr[0].len >> 2);
char *type = "";
retval = 0;
switch (version & 0xFF) {
case 1:
type = "proteon/mrouted ";
retval = 1;
break;
case 2:
case 3:
if (((version >> 8) & 0xFF) < 3) retval = 1;
/* Fall through */
case 4:
type = "mrouted ";
break;
case 10:
type = "cisco ";
}
printf(" [%s%d.%d] %s\n",
type, version & 0xFF, (version >> 8) & 0xFF,
why);
VAL_TO_MASK(smask, r->tr_smask);
while (p < ep) {
u_int32_t laddr = *p++;
int flags = (ntohl(*p) & 0xFF00) >> 8;
int n = ntohl(*p++) & 0xFF;
if (!(flags & (DVMRP_NF_DOWN | DVMRP_NF_DISABLED)) &&
(laddr & smask) == (qsrc & smask)) {
printf("%3d ", -(hops+2));
print_host(qsrc);
printf("\n");
return 1;
}
p += n;
}
return retval;
}
printf(" %s\n", why);
return 0;
}
char *scale(int *hop)
{
if (*hop > -1000 && *hop < 10000) return (" ms");
*hop /= 1000;
if (*hop > -1000 && *hop < 10000) return (" s ");
return ("s ");
}
/*
* Calculate and print one line of packet loss and packet rate statistics.
* Checks for count of all ones from mrouted 2.3 that doesn't have counters.
*/
#define NEITHER 0
#define INS 1
#define OUTS 2
#define BOTH 3
void stat_line(struct tr_resp *r, struct tr_resp *s, int have_next, int *rst)
{
int timediff = (fixtime(ntohl(s->tr_qarr)) -
fixtime(ntohl(r->tr_qarr))) >> 16;
int v_lost, v_pct;
int g_lost, g_pct;
int v_out = ntohl(s->tr_vifout) - ntohl(r->tr_vifout);
int g_out = ntohl(s->tr_pktcnt) - ntohl(r->tr_pktcnt);
int v_pps, g_pps;
char v_str[8], g_str[8];
int have = NEITHER;
int res = *rst;
if (timediff == 0) timediff = 1;
v_pps = v_out / timediff;
g_pps = g_out / timediff;
if (v_out && ((s->tr_vifout != 0xFFFFFFFF && s->tr_vifout != 0) ||
(r->tr_vifout != 0xFFFFFFFF && r->tr_vifout != 0)))
have |= OUTS;
if (have_next) {
--r, --s, --rst;
if ((s->tr_vifin != 0xFFFFFFFF && s->tr_vifin != 0) ||
(r->tr_vifin != 0xFFFFFFFF && r->tr_vifin != 0))
have |= INS;
if (*rst)
res = 1;
}
switch (have) {
case BOTH:
v_lost = v_out - (ntohl(s->tr_vifin) - ntohl(r->tr_vifin));
if (v_out) v_pct = (v_lost * 100 + (v_out >> 1)) / v_out;
else v_pct = 0;
if (-100 < v_pct && v_pct < 101 && v_out > 10)
snprintf(v_str, sizeof v_str, "%3d", v_pct);
else memcpy(v_str, " --", 4);
g_lost = g_out - (ntohl(s->tr_pktcnt) - ntohl(r->tr_pktcnt));
if (g_out) g_pct = (g_lost * 100 + (g_out >> 1))/ g_out;
else g_pct = 0;
if (-100 < g_pct && g_pct < 101 && g_out > 10)
snprintf(g_str, sizeof g_str, "%3d", g_pct);
else memcpy(g_str, " --", 4);
printf("%6d/%-5d=%s%%%4d pps",
v_lost, v_out, v_str, v_pps);
if (res)
printf("\n");
else
printf("%6d/%-5d=%s%%%4d pps\n",
g_lost, g_out, g_str, g_pps);
break;
case INS:
v_out = ntohl(s->tr_vifin) - ntohl(r->tr_vifin);
v_pps = v_out / timediff;
/* Fall through */
case OUTS:
printf(" %-5d %4d pps",
v_out, v_pps);
if (res)
printf("\n");
else
printf(" %-5d %4d pps\n",
g_out, g_pps);
break;
case NEITHER:
printf("\n");
break;
}
if (debug > 2) {
printf("\t\t\t\tv_in: %u ", ntohl(s->tr_vifin));
printf("v_out: %u ", ntohl(s->tr_vifout));
printf("pkts: %u\n", ntohl(s->tr_pktcnt));
printf("\t\t\t\tv_in: %u ", ntohl(r->tr_vifin));
printf("v_out: %u ", ntohl(r->tr_vifout));
printf("pkts: %u\n", ntohl(r->tr_pktcnt));
printf("\t\t\t\tv_in: %u ", ntohl(s->tr_vifin)-ntohl(r->tr_vifin));
printf("v_out: %u ", ntohl(s->tr_vifout) - ntohl(r->tr_vifout));
printf("pkts: %u ", ntohl(s->tr_pktcnt) - ntohl(r->tr_pktcnt));
printf("time: %d\n", timediff);
printf("\t\t\t\tres: %d\n", res);
}
}
/*
* A fixup to check if any pktcnt has been reset, and to fix the
* byteorder bugs in mrouted 3.6 on little-endian machines.
*/
void fixup_stats(struct resp_buf *base, struct resp_buf *prev, struct resp_buf *new)
{
int rno = base->len;
struct tr_resp *b = base->resps + rno;
struct tr_resp *p = prev->resps + rno;
struct tr_resp *n = new->resps + rno;
int *r = reset + rno;
int *s = swaps + rno;
int res;
/* Check for byte-swappers */
while (--rno >= 0) {
--n; --p; --b; --s;
if (*s || abs(ntohl(n->tr_vifout) - ntohl(p->tr_vifout)) > 100000) {
/* This host sends byteswapped reports; swap 'em */
if (!*s) {
*s = 1;
b->tr_qarr = byteswap(b->tr_qarr);
b->tr_vifin = byteswap(b->tr_vifin);
b->tr_vifout = byteswap(b->tr_vifout);
b->tr_pktcnt = byteswap(b->tr_pktcnt);
}
n->tr_qarr = byteswap(n->tr_qarr);
n->tr_vifin = byteswap(n->tr_vifin);
n->tr_vifout = byteswap(n->tr_vifout);
n->tr_pktcnt = byteswap(n->tr_pktcnt);
}
}
rno = base->len;
b = base->resps + rno;
p = prev->resps + rno;
n = new->resps + rno;
while (--rno >= 0) {
--n; --p; --b; --r;
res = ((ntohl(n->tr_pktcnt) < ntohl(b->tr_pktcnt)) ||
(ntohl(n->tr_pktcnt) < ntohl(p->tr_pktcnt)));
if (debug > 2)
printf("\t\tr=%d, res=%d\n", *r, res);
if (*r) {
if (res || *r > 1) {
/*
* This router appears to be a 3.4 with that nasty ol'
* neighbor version bug, which causes it to constantly
* reset. Just nuke the statistics for this node, and
* don't even bother giving it the benefit of the
* doubt from now on.
*/
p->tr_pktcnt = b->tr_pktcnt = n->tr_pktcnt;
r++;
} else {
/*
* This is simply the situation that the original
* fixup_stats was meant to deal with -- that a
* 3.3 or 3.4 router deleted a cache entry while
* traffic was still active.
*/
*r = 0;
break;
}
} else
*r = res;
}
if (rno < 0) return;
rno = base->len;
b = base->resps + rno;
p = prev->resps + rno;
while (--rno >= 0) (--b)->tr_pktcnt = (--p)->tr_pktcnt;
}
/*
* Print responses with statistics for forward path (from src to dst)
*/
int print_stats(struct resp_buf *base, struct resp_buf *prev, struct resp_buf *new)
{
int rtt, hop;
char *ms;
u_int32_t smask;
int rno = base->len - 1;
struct tr_resp *b = base->resps + rno;
struct tr_resp *p = prev->resps + rno;
struct tr_resp *n = new->resps + rno;
int *r = reset + rno;
u_long resptime = new->rtime;
u_long qarrtime = fixtime(ntohl(n->tr_qarr));
u_int ttl = n->tr_fttl;