blob: 2d4d7449c91b38172c1f9dce816f7e8f5856a9c0 [file] [log] [blame]
/*
* 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, and (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.
* 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.
*
* Original code by Andy Heffernan (ahh@juniper.net)
*/
#ifndef lint
static const char rcsid[] _U_ =
"@(#) $Header: /tcpdump/master/tcpdump/print-pgm.c,v 1.5 2005-06-07 22:05:58 guy Exp $";
#endif
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <tcpdump-stdinc.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "interface.h"
#include "extract.h"
#include "addrtoname.h"
#include "ip.h"
#ifdef INET6
#include "ip6.h"
#endif
#include "ipproto.h"
/*
* PGM header (RFC 3208)
*/
struct pgm_header {
u_int16_t pgm_sport;
u_int16_t pgm_dport;
u_int8_t pgm_type;
u_int8_t pgm_options;
u_int16_t pgm_sum;
u_int8_t pgm_gsid[6];
u_int16_t pgm_length;
};
struct pgm_spm {
u_int32_t pgms_seq;
u_int32_t pgms_trailseq;
u_int32_t pgms_leadseq;
u_int16_t pgms_nla_afi;
u_int16_t pgms_reserved;
/* ... u_int8_t pgms_nla[0]; */
/* ... options */
};
struct pgm_nak {
u_int32_t pgmn_seq;
u_int16_t pgmn_source_afi;
u_int16_t pgmn_reserved;
/* ... u_int8_t pgmn_source[0]; */
/* ... u_int16_t pgmn_group_afi */
/* ... u_int16_t pgmn_reserved2; */
/* ... u_int8_t pgmn_group[0]; */
/* ... options */
};
struct pgm_ack {
u_int32_t pgma_rx_max_seq;
u_int32_t pgma_bitmap;
/* ... options */
};
struct pgm_poll {
u_int32_t pgmp_seq;
u_int16_t pgmp_round;
u_int16_t pgmp_reserved;
/* ... options */
};
struct pgm_polr {
u_int32_t pgmp_seq;
u_int16_t pgmp_round;
u_int16_t pgmp_subtype;
u_int16_t pgmp_nla_afi;
u_int16_t pgmp_reserved;
/* ... u_int8_t pgmp_nla[0]; */
/* ... options */
};
struct pgm_data {
u_int32_t pgmd_seq;
u_int32_t pgmd_trailseq;
/* ... options */
};
typedef enum _pgm_type {
PGM_SPM = 0, /* source path message */
PGM_POLL = 1, /* POLL Request */
PGM_POLR = 2, /* POLL Response */
PGM_ODATA = 4, /* original data */
PGM_RDATA = 5, /* repair data */
PGM_NAK = 8, /* NAK */
PGM_NULLNAK = 9, /* Null NAK */
PGM_NCF = 10, /* NAK Confirmation */
PGM_ACK = 11, /* ACK for congestion control */
PGM_SPMR = 12, /* SPM request */
PGM_MAX = 255
} pgm_type;
#define PGM_OPT_BIT_PRESENT 0x01
#define PGM_OPT_BIT_NETWORK 0x02
#define PGM_OPT_BIT_VAR_PKTLEN 0x40
#define PGM_OPT_BIT_PARITY 0x80
#define PGM_OPT_LENGTH 0x00
#define PGM_OPT_FRAGMENT 0x01
#define PGM_OPT_NAK_LIST 0x02
#define PGM_OPT_JOIN 0x03
#define PGM_OPT_NAK_BO_IVL 0x04
#define PGM_OPT_NAK_BO_RNG 0x05
#define PGM_OPT_REDIRECT 0x07
#define PGM_OPT_PARITY_PRM 0x08
#define PGM_OPT_PARITY_GRP 0x09
#define PGM_OPT_CURR_TGSIZE 0x0A
#define PGM_OPT_NBR_UNREACH 0x0B
#define PGM_OPT_PATH_NLA 0x0C
#define PGM_OPT_SYN 0x0D
#define PGM_OPT_FIN 0x0E
#define PGM_OPT_RST 0x0F
#define PGM_OPT_CR 0x10
#define PGM_OPT_CRQST 0x11
#define PGM_OPT_PGMCC_DATA 0x12
#define PGM_OPT_PGMCC_FEEDBACK 0x13
#define PGM_OPT_MASK 0x7f
#define PGM_OPT_END 0x80 /* end of options marker */
#define PGM_MIN_OPT_LEN 4
#ifndef AFI_IP
#define AFI_IP 1
#define AFI_IP6 2
#endif
void
pgm_print(register const u_char *bp, register u_int length,
register const u_char *bp2)
{
register const struct pgm_header *pgm;
register const struct ip *ip;
register char ch;
u_int16_t sport, dport;
int addr_size;
const void *nla;
int nla_af;
#ifdef INET6
char nla_buf[INET6_ADDRSTRLEN];
register const struct ip6_hdr *ip6;
#else
char nla_buf[INET_ADDRSTRLEN];
#endif
u_int8_t opt_type, opt_len, flags1, flags2;
u_int32_t seq, opts_len, len, offset;
pgm = (struct pgm_header *)bp;
ip = (struct ip *)bp2;
#ifdef INET6
if (IP_V(ip) == 6)
ip6 = (struct ip6_hdr *)bp2;
else
ip6 = NULL;
#else /* INET6 */
if (IP_V(ip) == 6) {
(void)printf("Can't handle IPv6");
return;
}
#endif /* INET6 */
ch = '\0';
if (!TTEST(pgm->pgm_dport)) {
#ifdef INET6
if (ip6) {
(void)printf("%s > %s: [|pgm]",
ip6addr_string(&ip6->ip6_src),
ip6addr_string(&ip6->ip6_dst));
return;
} else
#endif /* INET6 */
{
(void)printf("%s > %s: [|pgm]",
ipaddr_string(&ip->ip_src),
ipaddr_string(&ip->ip_dst));
return;
}
}
sport = EXTRACT_16BITS(&pgm->pgm_sport);
dport = EXTRACT_16BITS(&pgm->pgm_dport);
#ifdef INET6
if (ip6) {
if (ip6->ip6_nxt == IPPROTO_PGM) {
(void)printf("%s.%s > %s.%s: ",
ip6addr_string(&ip6->ip6_src),
tcpport_string(sport),
ip6addr_string(&ip6->ip6_dst),
tcpport_string(dport));
} else {
(void)printf("%s > %s: ",
tcpport_string(sport), tcpport_string(dport));
}
} else
#endif /*INET6*/
{
if (ip->ip_p == IPPROTO_PGM) {
(void)printf("%s.%s > %s.%s: ",
ipaddr_string(&ip->ip_src),
tcpport_string(sport),
ipaddr_string(&ip->ip_dst),
tcpport_string(dport));
} else {
(void)printf("%s > %s: ",
tcpport_string(sport), tcpport_string(dport));
}
}
TCHECK(*pgm);
(void)printf("PGM, length %u", pgm->pgm_length);
if (!vflag)
return;
if (length > pgm->pgm_length)
length = pgm->pgm_length;
(void)printf(" 0x%02x%02x%02x%02x%02x%02x ",
pgm->pgm_gsid[0],
pgm->pgm_gsid[1],
pgm->pgm_gsid[2],
pgm->pgm_gsid[3],
pgm->pgm_gsid[4],
pgm->pgm_gsid[5]);
switch (pgm->pgm_type) {
case PGM_SPM: {
struct pgm_spm *spm;
spm = (struct pgm_spm *)(pgm + 1);
TCHECK(*spm);
switch (EXTRACT_16BITS(&spm->pgms_nla_afi)) {
case AFI_IP:
addr_size = sizeof(struct in_addr);
nla_af = AF_INET;
break;
#ifdef INET6
case AFI_IP6:
addr_size = sizeof(struct in6_addr);
nla_af = AF_INET6;
break;
#endif
default:
goto trunc;
break;
}
bp = (u_char *) (spm + 1);
TCHECK2(*bp, addr_size);
nla = bp;
bp += addr_size;
inet_ntop(nla_af, nla, nla_buf, sizeof(nla_buf));
(void)printf("SPM seq %u trail %u lead %u nla %s",
EXTRACT_32BITS(&spm->pgms_seq),
EXTRACT_32BITS(&spm->pgms_trailseq),
EXTRACT_32BITS(&spm->pgms_leadseq),
nla_buf);
break;
}
case PGM_POLL: {
struct pgm_poll *poll;
poll = (struct pgm_poll *)(pgm + 1);
TCHECK(*poll);
(void)printf("POLL seq %u round %u",
EXTRACT_32BITS(&poll->pgmp_seq),
EXTRACT_16BITS(&poll->pgmp_round));
bp = (u_char *) (poll + 1);
break;
}
case PGM_POLR: {
struct pgm_polr *polr;
u_int32_t ivl, rnd, mask;
polr = (struct pgm_polr *)(pgm + 1);
TCHECK(*polr);
switch (EXTRACT_16BITS(&polr->pgmp_nla_afi)) {
case AFI_IP:
addr_size = sizeof(struct in_addr);
nla_af = AF_INET;
break;
#ifdef INET6
case AFI_IP6:
addr_size = sizeof(struct in6_addr);
nla_af = AF_INET6;
break;
#endif
default:
goto trunc;
break;
}
bp = (u_char *) (polr + 1);
TCHECK2(*bp, addr_size);
nla = bp;
bp += addr_size;
inet_ntop(nla_af, nla, nla_buf, sizeof(nla_buf));
TCHECK2(*bp, sizeof(u_int32_t));
ivl = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
TCHECK2(*bp, sizeof(u_int32_t));
rnd = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
TCHECK2(*bp, sizeof(u_int32_t));
mask = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
(void)printf("POLR seq %u round %u nla %s ivl %u rnd 0x%08x "
"mask 0x%08x", EXTRACT_32BITS(&polr->pgmp_seq),
EXTRACT_16BITS(&polr->pgmp_round), nla_buf, ivl, rnd, mask);
break;
}
case PGM_ODATA: {
struct pgm_data *odata;
odata = (struct pgm_data *)(pgm + 1);
TCHECK(*odata);
(void)printf("ODATA trail %u seq %u",
EXTRACT_32BITS(&odata->pgmd_trailseq),
EXTRACT_32BITS(&odata->pgmd_seq));
bp = (u_char *) (odata + 1);
break;
}
case PGM_RDATA: {
struct pgm_data *rdata;
rdata = (struct pgm_data *)(pgm + 1);
TCHECK(*rdata);
(void)printf("RDATA trail %u seq %u",
EXTRACT_32BITS(&rdata->pgmd_trailseq),
EXTRACT_32BITS(&rdata->pgmd_seq));
bp = (u_char *) (rdata + 1);
break;
}
case PGM_NAK:
case PGM_NULLNAK:
case PGM_NCF: {
struct pgm_nak *nak;
const void *source, *group;
int source_af, group_af;
#ifdef INET6
char source_buf[INET6_ADDRSTRLEN], group_buf[INET6_ADDRSTRLEN];
#else
char source_buf[INET_ADDRSTRLEN], group_buf[INET_ADDRSTRLEN];
#endif
nak = (struct pgm_nak *)(pgm + 1);
TCHECK(*nak);
/*
* Skip past the source, saving info along the way
* and stopping if we don't have enough.
*/
switch (EXTRACT_16BITS(&nak->pgmn_source_afi)) {
case AFI_IP:
addr_size = sizeof(struct in_addr);
source_af = AF_INET;
break;
#ifdef INET6
case AFI_IP6:
addr_size = sizeof(struct in6_addr);
source_af = AF_INET6;
break;
#endif
default:
goto trunc;
break;
}
bp = (u_char *) (nak + 1);
TCHECK2(*bp, addr_size);
source = bp;
bp += addr_size;
/*
* Skip past the group, saving info along the way
* and stopping if we don't have enough.
*/
switch (EXTRACT_16BITS(bp)) {
case AFI_IP:
addr_size = sizeof(struct in_addr);
group_af = AF_INET;
break;
#ifdef INET6
case AFI_IP6:
addr_size = sizeof(struct in6_addr);
group_af = AF_INET6;
break;
#endif
default:
goto trunc;
break;
}
bp += (2 * sizeof(u_int16_t));
TCHECK2(*bp, addr_size);
group = bp;
bp += addr_size;
/*
* Options decoding can go here.
*/
inet_ntop(source_af, source, source_buf, sizeof(source_buf));
inet_ntop(group_af, group, group_buf, sizeof(group_buf));
switch (pgm->pgm_type) {
case PGM_NAK:
(void)printf("NAK ");
break;
case PGM_NULLNAK:
(void)printf("NNAK ");
break;
case PGM_NCF:
(void)printf("NCF ");
break;
default:
break;
}
(void)printf("(%s -> %s), seq %u",
source_buf, group_buf, EXTRACT_32BITS(&nak->pgmn_seq));
break;
}
case PGM_ACK: {
struct pgm_ack *ack;
ack = (struct pgm_ack *)(pgm + 1);
TCHECK(*ack);
(void)printf("ACK seq %u",
EXTRACT_32BITS(&ack->pgma_rx_max_seq));
bp = (u_char *) (ack + 1);
break;
}
case PGM_SPMR:
(void)printf("SPMR");
break;
default:
(void)printf("UNKNOWN type %0x02x", pgm->pgm_type);
break;
}
if (pgm->pgm_options & PGM_OPT_BIT_PRESENT) {
/*
* make sure there's enough for the first option header
*/
if (!TTEST2(*bp, PGM_MIN_OPT_LEN)) {
(void)printf("[|OPT]");
return;
}
/*
* That option header MUST be an OPT_LENGTH option
* (see the first paragraph of section 9.1 in RFC 3208).
*/
opt_type = *bp++;
if ((opt_type & PGM_OPT_MASK) != PGM_OPT_LENGTH) {
(void)printf("[First option bad, should be PGM_OPT_LENGTH, is %u]", opt_type & PGM_OPT_MASK);
return;
}
opt_len = *bp++;
if (opt_len != 4) {
(void)printf("[Bad OPT_LENGTH option, length %u != 4]", opt_len);
return;
}
opts_len = EXTRACT_16BITS(bp);
if (opts_len < 4) {
(void)printf("[Bad total option length %u < 4]", opts_len);
return;
}
bp += sizeof(u_int16_t);
(void)printf(" OPTS LEN %d", opts_len);
opts_len -= 4;
while (opts_len) {
if (opts_len < PGM_MIN_OPT_LEN) {
(void)printf("[Total option length leaves no room for final option]");
return;
}
opt_type = *bp++;
opt_len = *bp++;
if (opt_len < PGM_MIN_OPT_LEN) {
(void)printf("[Bad option, length %u < %u]", opt_len,
PGM_MIN_OPT_LEN);
break;
}
if (opts_len < opt_len) {
(void)printf("[Total option length leaves no room for final option]");
return;
}
if (!TTEST2(*bp, opt_len - 2)) {
(void)printf(" [|OPT]");
return;
}
switch (opt_type & PGM_OPT_MASK) {
case PGM_OPT_LENGTH:
if (opt_len != 4) {
(void)printf("[Bad OPT_LENGTH option, length %u != 4]", opt_len);
return;
}
(void)printf(" OPTS LEN (extra?) %d", EXTRACT_16BITS(bp));
bp += sizeof(u_int16_t);
opts_len -= 4;
break;
case PGM_OPT_FRAGMENT:
if (opt_len != 16) {
(void)printf("[Bad OPT_FRAGMENT option, length %u != 16]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
seq = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
offset = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
len = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
(void)printf(" FRAG seq %u off %u len %u", seq, offset, len);
opts_len -= 16;
break;
case PGM_OPT_NAK_LIST:
flags1 = *bp++;
flags2 = *bp++;
opt_len -= sizeof(u_int32_t); /* option header */
(void)printf(" NAK LIST");
while (opt_len) {
if (opt_len < sizeof(u_int32_t)) {
(void)printf("[Option length not a multiple of 4]");
return;
}
TCHECK2(*bp, sizeof(u_int32_t));
(void)printf(" %u", EXTRACT_32BITS(bp));
bp += sizeof(u_int32_t);
opt_len -= sizeof(u_int32_t);
opts_len -= sizeof(u_int32_t);
}
break;
case PGM_OPT_JOIN:
if (opt_len != 8) {
(void)printf("[Bad OPT_JOIN option, length %u != 8]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
seq = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
(void)printf(" JOIN %u", seq);
opts_len -= 8;
break;
case PGM_OPT_NAK_BO_IVL:
if (opt_len != 12) {
(void)printf("[Bad OPT_NAK_BO_IVL option, length %u != 12]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
offset = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
seq = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
(void)printf(" BACKOFF ivl %u ivlseq %u", offset, seq);
opts_len -= 12;
break;
case PGM_OPT_NAK_BO_RNG:
if (opt_len != 12) {
(void)printf("[Bad OPT_NAK_BO_RNG option, length %u != 12]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
offset = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
seq = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
(void)printf(" BACKOFF max %u min %u", offset, seq);
opts_len -= 12;
break;
case PGM_OPT_REDIRECT:
flags1 = *bp++;
flags2 = *bp++;
switch (EXTRACT_16BITS(bp)) {
case AFI_IP:
addr_size = sizeof(struct in_addr);
nla_af = AF_INET;
break;
#ifdef INET6
case AFI_IP6:
addr_size = sizeof(struct in6_addr);
nla_af = AF_INET6;
break;
#endif
default:
goto trunc;
break;
}
bp += (2 * sizeof(u_int16_t));
if (opt_len != 4 + addr_size) {
(void)printf("[Bad OPT_REDIRECT option, length %u != 4 + address size]", opt_len);
return;
}
TCHECK2(*bp, addr_size);
nla = bp;
bp += addr_size;
inet_ntop(nla_af, nla, nla_buf, sizeof(nla_buf));
(void)printf(" REDIRECT %s", (char *)nla);
opts_len -= 4 + addr_size;
break;
case PGM_OPT_PARITY_PRM:
if (opt_len != 8) {
(void)printf("[Bad OPT_PARITY_PRM option, length %u != 8]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
len = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
(void)printf(" PARITY MAXTGS %u", len);
opts_len -= 8;
break;
case PGM_OPT_PARITY_GRP:
if (opt_len != 8) {
(void)printf("[Bad OPT_PARITY_GRP option, length %u != 8]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
seq = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
(void)printf(" PARITY GROUP %u", seq);
opts_len -= 8;
break;
case PGM_OPT_CURR_TGSIZE:
if (opt_len != 8) {
(void)printf("[Bad OPT_CURR_TGSIZE option, length %u != 8]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
len = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
(void)printf(" PARITY ATGS %u", len);
opts_len -= 8;
break;
case PGM_OPT_NBR_UNREACH:
if (opt_len != 4) {
(void)printf("[Bad OPT_NBR_UNREACH option, length %u != 4]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
(void)printf(" NBR_UNREACH");
opts_len -= 4;
break;
case PGM_OPT_PATH_NLA:
(void)printf(" PATH_NLA [%d]", opt_len);
bp += opt_len;
opts_len -= opt_len;
break;
case PGM_OPT_SYN:
if (opt_len != 4) {
(void)printf("[Bad OPT_SYN option, length %u != 4]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
(void)printf(" SYN");
opts_len -= 4;
break;
case PGM_OPT_FIN:
if (opt_len != 4) {
(void)printf("[Bad OPT_FIN option, length %u != 4]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
(void)printf(" FIN");
opts_len -= 4;
break;
case PGM_OPT_RST:
if (opt_len != 4) {
(void)printf("[Bad OPT_RST option, length %u != 4]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
(void)printf(" RST");
opts_len -= 4;
break;
case PGM_OPT_CR:
(void)printf(" CR");
bp += opt_len;
opts_len -= opt_len;
break;
case PGM_OPT_CRQST:
if (opt_len != 4) {
(void)printf("[Bad OPT_CRQST option, length %u != 4]", opt_len);
return;
}
flags1 = *bp++;
flags2 = *bp++;
(void)printf(" CRQST");
opts_len -= 4;
break;
case PGM_OPT_PGMCC_DATA:
flags1 = *bp++;
flags2 = *bp++;
offset = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
switch (EXTRACT_16BITS(bp)) {
case AFI_IP:
addr_size = sizeof(struct in_addr);
nla_af = AF_INET;
break;
#ifdef INET6
case AFI_IP6:
addr_size = sizeof(struct in6_addr);
nla_af = AF_INET6;
break;
#endif
default:
goto trunc;
break;
}
bp += (2 * sizeof(u_int16_t));
if (opt_len != 12 + addr_size) {
(void)printf("[Bad OPT_PGMCC_DATA option, length %u != 12 + address size]", opt_len);
return;
}
TCHECK2(*bp, addr_size);
nla = bp;
bp += addr_size;
inet_ntop(nla_af, nla, nla_buf, sizeof(nla_buf));
(void)printf(" PGMCC DATA %u %s", offset, (char*)nla);
opts_len -= 16;
break;
case PGM_OPT_PGMCC_FEEDBACK:
flags1 = *bp++;
flags2 = *bp++;
offset = EXTRACT_32BITS(bp);
bp += sizeof(u_int32_t);
switch (EXTRACT_16BITS(bp)) {
case AFI_IP:
addr_size = sizeof(struct in_addr);
nla_af = AF_INET;
break;
#ifdef INET6
case AFI_IP6:
addr_size = sizeof(struct in6_addr);
nla_af = AF_INET6;
break;
#endif
default:
goto trunc;
break;
}
bp += (2 * sizeof(u_int16_t));
if (opt_len != 12 + addr_size) {
(void)printf("[Bad OPT_PGMCC_FEEDBACK option, length %u != 12 + address size]", opt_len);
return;
}
TCHECK2(*bp, addr_size);
nla = bp;
bp += addr_size;
inet_ntop(nla_af, nla, nla_buf, sizeof(nla_buf));
(void)printf(" PGMCC FEEDBACK %u %s", offset, (char*)nla);
opts_len -= 16;
break;
default:
(void)printf(" OPT_%02X [%d] ", opt_type, opt_len);
bp += opt_len;
opts_len -= opt_len;
break;
}
if (opt_type & PGM_OPT_END)
break;
}
}
(void)printf(" [%u]", EXTRACT_16BITS(&pgm->pgm_length));
return;
trunc:
fputs("[|pgm]", stdout);
if (ch != '\0')
putchar('>');
}