freebsd-dev/libexec/telnetd/telnetd.c
1999-08-28 00:22:10 +00:00

1566 lines
38 KiB
C

/*
* Copyright (c) 1989, 1993
* 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 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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 BY THE REGENTS 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 REGENTS 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.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1989, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)telnetd.c 8.2 (Berkeley) 12/15/93";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include "telnetd.h"
#include "pathnames.h"
#if defined(_SC_CRAY_SECURE_SYS) && !defined(SCM_SECURITY)
/*
* UNICOS 6.0/6.1 do not have SCM_SECURITY defined, so we can
* use it to tell us to turn off all the socket security code,
* since that is only used in UNICOS 7.0 and later.
*/
# undef _SC_CRAY_SECURE_SYS
#endif
#include <err.h>
#include <arpa/inet.h>
#include <sys/mman.h>
#include <libutil.h>
#include <utmp.h>
#if defined(_SC_CRAY_SECURE_SYS)
#include <sys/sysv.h>
#include <sys/secdev.h>
# ifdef SO_SEC_MULTI /* 8.0 code */
#include <sys/secparm.h>
#include <sys/usrv.h>
# endif /* SO_SEC_MULTI */
int secflag;
char tty_dev[16];
struct secdev dv;
struct sysv sysv;
# ifdef SO_SEC_MULTI /* 8.0 code */
struct socksec ss;
# else /* SO_SEC_MULTI */ /* 7.0 code */
struct socket_security ss;
# endif /* SO_SEC_MULTI */
#endif /* _SC_CRAY_SECURE_SYS */
#if defined(AUTHENTICATION)
#include <libtelnet/auth.h>
int auth_level = 0;
#endif
#if defined(SecurID)
int require_SecurID = 0;
#endif
char remote_hostname[MAXHOSTNAMELEN];
int utmp_len = sizeof(remote_hostname) - 1;
int registerd_host_only = 0;
#ifdef STREAMSPTY
# include <stropts.h>
# include <termio.h>
/* make sure we don't get the bsd version */
# include "/usr/include/sys/tty.h"
# include <sys/ptyvar.h>
/*
* Because of the way ptyibuf is used with streams messages, we need
* ptyibuf+1 to be on a full-word boundary. The following wierdness
* is simply to make that happen.
*/
long ptyibufbuf[BUFSIZ/sizeof(long)+1];
char *ptyibuf = ((char *)&ptyibufbuf[1])-1;
char *ptyip = ((char *)&ptyibufbuf[1])-1;
char ptyibuf2[BUFSIZ];
unsigned char ctlbuf[BUFSIZ];
struct strbuf strbufc, strbufd;
int readstream();
#else /* ! STREAMPTY */
/*
* I/O data buffers,
* pointers, and counters.
*/
char ptyibuf[BUFSIZ], *ptyip = ptyibuf;
char ptyibuf2[BUFSIZ];
#endif /* ! STREAMPTY */
int hostinfo = 1; /* do we print login banner? */
#ifdef CRAY
extern int newmap; /* nonzero if \n maps to ^M^J */
int lowpty = 0, highpty; /* low, high pty numbers */
#endif /* CRAY */
int debug = 0;
int keepalive = 1;
char *altlogin;
void doit __P((struct sockaddr_in *));
int terminaltypeok __P((char *));
void startslave __P((char *, int, char *));
extern void usage P((void));
/*
* The string to pass to getopt(). We do it this way so
* that only the actual options that we support will be
* passed off to getopt().
*/
char valid_opts[] = {
'd', ':', 'h', 'k', 'n', 'p', ':', 'S', ':', 'u', ':', 'U',
#ifdef AUTHENTICATION
'a', ':', 'X', ':',
#endif
#ifdef BFTPDAEMON
'B',
#endif
#ifdef DIAGNOSTICS
'D', ':',
#endif
#if defined(CRAY) && defined(NEWINIT)
'I', ':',
#endif
#ifdef LINEMODE
'l',
#endif
#ifdef CRAY
'r', ':',
#endif
#ifdef SecurID
's',
#endif
'\0'
};
int
main(argc, argv)
char *argv[];
{
struct sockaddr_in from;
int on = 1, fromlen;
register int ch;
#if defined(IPPROTO_IP) && defined(IP_TOS)
int tos = -1;
#endif
pfrontp = pbackp = ptyobuf;
netip = netibuf;
nfrontp = nbackp = netobuf;
/*
* This initialization causes linemode to default to a configuration
* that works on all telnet clients, including the FreeBSD client.
* This is not quite the same as the telnet client issuing a "mode
* character" command, but has most of the same benefits, and is
* preferable since some clients (like usofts) don't have the
* mode character command anyway and linemode breaks things.
* The most notable symptom of fix is that csh "set filec" operations
* like <ESC> (filename completion) and ^D (choices) keys now work
* in telnet sessions and can be used more than once on the same line.
* CR/LF handling is also corrected in some termio modes. This
* change resolves problem reports bin/771 and bin/1037.
*/
linemode=1; /*Default to mode that works on bulk of clients*/
#ifdef CRAY
/*
* Get number of pty's before trying to process options,
* which may include changing pty range.
*/
highpty = getnpty();
#endif /* CRAY */
while ((ch = getopt(argc, argv, valid_opts)) != -1) {
switch(ch) {
#ifdef AUTHENTICATION
case 'a':
/*
* Check for required authentication level
*/
if (strcmp(optarg, "debug") == 0) {
extern int auth_debug_mode;
auth_debug_mode = 1;
} else if (strcasecmp(optarg, "none") == 0) {
auth_level = 0;
} else if (strcasecmp(optarg, "other") == 0) {
auth_level = AUTH_OTHER;
} else if (strcasecmp(optarg, "user") == 0) {
auth_level = AUTH_USER;
} else if (strcasecmp(optarg, "valid") == 0) {
auth_level = AUTH_VALID;
} else if (strcasecmp(optarg, "off") == 0) {
/*
* This hack turns off authentication
*/
auth_level = -1;
} else {
warnx("unknown authorization level for -a");
}
break;
#endif /* AUTHENTICATION */
#ifdef BFTPDAEMON
case 'B':
bftpd++;
break;
#endif /* BFTPDAEMON */
case 'd':
if (strcmp(optarg, "ebug") == 0) {
debug++;
break;
}
usage();
/* NOTREACHED */
break;
#ifdef DIAGNOSTICS
case 'D':
/*
* Check for desired diagnostics capabilities.
*/
if (!strcmp(optarg, "report")) {
diagnostic |= TD_REPORT|TD_OPTIONS;
} else if (!strcmp(optarg, "exercise")) {
diagnostic |= TD_EXERCISE;
} else if (!strcmp(optarg, "netdata")) {
diagnostic |= TD_NETDATA;
} else if (!strcmp(optarg, "ptydata")) {
diagnostic |= TD_PTYDATA;
} else if (!strcmp(optarg, "options")) {
diagnostic |= TD_OPTIONS;
} else {
usage();
/* NOT REACHED */
}
break;
#endif /* DIAGNOSTICS */
case 'h':
hostinfo = 0;
break;
#if defined(CRAY) && defined(NEWINIT)
case 'I':
{
extern char *gen_id;
gen_id = optarg;
break;
}
#endif /* defined(CRAY) && defined(NEWINIT) */
#ifdef LINEMODE
case 'l':
alwayslinemode = 1;
break;
#endif /* LINEMODE */
case 'k':
#if defined(LINEMODE) && defined(KLUDGELINEMODE)
lmodetype = NO_AUTOKLUDGE;
#else
/* ignore -k option if built without kludge linemode */
#endif /* defined(LINEMODE) && defined(KLUDGELINEMODE) */
break;
case 'n':
keepalive = 0;
break;
case 'p':
altlogin = optarg;
break;
#ifdef CRAY
case 'r':
{
char *strchr();
char *c;
/*
* Allow the specification of alterations
* to the pty search range. It is legal to
* specify only one, and not change the
* other from its default.
*/
c = strchr(optarg, '-');
if (c) {
*c++ = '\0';
highpty = atoi(c);
}
if (*optarg != '\0')
lowpty = atoi(optarg);
if ((lowpty > highpty) || (lowpty < 0) ||
(highpty > 32767)) {
usage();
/* NOT REACHED */
}
break;
}
#endif /* CRAY */
#ifdef SecurID
case 's':
/* SecurID required */
require_SecurID = 1;
break;
#endif /* SecurID */
case 'S':
#ifdef HAS_GETTOS
if ((tos = parsetos(optarg, "tcp")) < 0)
warnx("%s%s%s",
"bad TOS argument '", optarg,
"'; will try to use default TOS");
#else
warnx("TOS option unavailable; -S flag not supported");
#endif
break;
case 'u':
utmp_len = atoi(optarg);
if (utmp_len < 0)
utmp_len = -utmp_len;
if (utmp_len >= sizeof(remote_hostname))
utmp_len = sizeof(remote_hostname) - 1;
break;
case 'U':
registerd_host_only = 1;
break;
#ifdef AUTHENTICATION
case 'X':
/*
* Check for invalid authentication types
*/
auth_disable_name(optarg);
break;
#endif /* AUTHENTICATION */
default:
warnx("%c: unknown option", ch);
/* FALLTHROUGH */
case '?':
usage();
/* NOTREACHED */
}
}
argc -= optind;
argv += optind;
if (debug) {
int s, ns, foo;
struct servent *sp;
static struct sockaddr_in sin = { AF_INET };
if (argc > 1) {
usage();
/* NOT REACHED */
} else if (argc == 1) {
if ((sp = getservbyname(*argv, "tcp"))) {
sin.sin_port = sp->s_port;
} else {
sin.sin_port = atoi(*argv);
if ((int)sin.sin_port <= 0) {
warnx("%s: bad port #", *argv);
usage();
/* NOT REACHED */
}
sin.sin_port = htons((u_short)sin.sin_port);
}
} else {
sp = getservbyname("telnet", "tcp");
if (sp == 0)
errx(1, "tcp/telnet: unknown service");
sin.sin_port = sp->s_port;
}
s = socket(AF_INET, SOCK_STREAM, 0);
if (s < 0)
err(1, "socket");
(void) setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
(char *)&on, sizeof(on));
if (bind(s, (struct sockaddr *)&sin, sizeof sin) < 0)
err(1, "bind");
if (listen(s, 1) < 0)
err(1, "listen");
foo = sizeof sin;
ns = accept(s, (struct sockaddr *)&sin, &foo);
if (ns < 0)
err(1, "accept");
(void) dup2(ns, 0);
(void) close(ns);
(void) close(s);
#ifdef convex
} else if (argc == 1) {
; /* VOID*/ /* Just ignore the host/port name */
#endif
} else if (argc > 0) {
usage();
/* NOT REACHED */
}
#if defined(_SC_CRAY_SECURE_SYS)
secflag = sysconf(_SC_CRAY_SECURE_SYS);
/*
* Get socket's security label
*/
if (secflag) {
int szss = sizeof(ss);
#ifdef SO_SEC_MULTI /* 8.0 code */
int sock_multi;
int szi = sizeof(int);
#endif /* SO_SEC_MULTI */
bzero((char *)&dv, sizeof(dv));
if (getsysv(&sysv, sizeof(struct sysv)) != 0)
err(1, "getsysv");
/*
* Get socket security label and set device values
* {security label to be set on ttyp device}
*/
#ifdef SO_SEC_MULTI /* 8.0 code */
if ((getsockopt(0, SOL_SOCKET, SO_SECURITY,
(char *)&ss, &szss) < 0) ||
(getsockopt(0, SOL_SOCKET, SO_SEC_MULTI,
(char *)&sock_multi, &szi) < 0)) {
err(1, "getsockopt");
} else {
dv.dv_actlvl = ss.ss_actlabel.lt_level;
dv.dv_actcmp = ss.ss_actlabel.lt_compart;
if (!sock_multi) {
dv.dv_minlvl = dv.dv_maxlvl = dv.dv_actlvl;
dv.dv_valcmp = dv.dv_actcmp;
} else {
dv.dv_minlvl = ss.ss_minlabel.lt_level;
dv.dv_maxlvl = ss.ss_maxlabel.lt_level;
dv.dv_valcmp = ss.ss_maxlabel.lt_compart;
}
dv.dv_devflg = 0;
}
#else /* SO_SEC_MULTI */ /* 7.0 code */
if (getsockopt(0, SOL_SOCKET, SO_SECURITY,
(char *)&ss, &szss) >= 0) {
dv.dv_actlvl = ss.ss_slevel;
dv.dv_actcmp = ss.ss_compart;
dv.dv_minlvl = ss.ss_minlvl;
dv.dv_maxlvl = ss.ss_maxlvl;
dv.dv_valcmp = ss.ss_maxcmp;
}
#endif /* SO_SEC_MULTI */
}
#endif /* _SC_CRAY_SECURE_SYS */
openlog("telnetd", LOG_PID | LOG_ODELAY, LOG_DAEMON);
fromlen = sizeof (from);
if (getpeername(0, (struct sockaddr *)&from, &fromlen) < 0) {
warn("getpeername");
_exit(1);
}
if (keepalive &&
setsockopt(0, SOL_SOCKET, SO_KEEPALIVE,
(char *)&on, sizeof (on)) < 0) {
syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m");
}
#if defined(IPPROTO_IP) && defined(IP_TOS)
{
# if defined(HAS_GETTOS)
struct tosent *tp;
if (tos < 0 && (tp = gettosbyname("telnet", "tcp")))
tos = tp->t_tos;
# endif
if (tos < 0)
tos = 020; /* Low Delay bit */
if (tos
&& (setsockopt(0, IPPROTO_IP, IP_TOS,
(char *)&tos, sizeof(tos)) < 0)
&& (errno != ENOPROTOOPT) )
syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
}
#endif /* defined(IPPROTO_IP) && defined(IP_TOS) */
net = 0;
doit(&from);
/* NOTREACHED */
return(0);
} /* end of main */
void
usage()
{
fprintf(stderr, "usage: telnetd");
#ifdef AUTHENTICATION
fprintf(stderr, " [-a (debug|other|user|valid|off|none)]\n\t");
#endif
#ifdef BFTPDAEMON
fprintf(stderr, " [-B]");
#endif
fprintf(stderr, " [-debug]");
#ifdef DIAGNOSTICS
fprintf(stderr, " [-D (options|report|exercise|netdata|ptydata)]\n\t");
#endif
#ifdef AUTHENTICATION
fprintf(stderr, " [-edebug]");
#endif
fprintf(stderr, " [-h]");
#if defined(CRAY) && defined(NEWINIT)
fprintf(stderr, " [-Iinitid]");
#endif
#if defined(LINEMODE) && defined(KLUDGELINEMODE)
fprintf(stderr, " [-k]");
#endif
#ifdef LINEMODE
fprintf(stderr, " [-l]");
#endif
fprintf(stderr, " [-n]");
#ifdef CRAY
fprintf(stderr, " [-r[lowpty]-[highpty]]");
#endif
fprintf(stderr, "\n\t");
#ifdef SecurID
fprintf(stderr, " [-s]");
#endif
#ifdef HAS_GETTOS
fprintf(stderr, " [-S tos]");
#endif
#ifdef AUTHENTICATION
fprintf(stderr, " [-X auth-type]");
#endif
fprintf(stderr, " [-u utmp_hostname_length] [-U]");
fprintf(stderr, " [port]\n");
exit(1);
}
/*
* getterminaltype
*
* Ask the other end to send along its terminal type and speed.
* Output is the variable terminaltype filled in.
*/
static unsigned char ttytype_sbbuf[] = {
IAC, SB, TELOPT_TTYPE, TELQUAL_SEND, IAC, SE
};
int
getterminaltype(name)
char *name;
{
int retval = -1;
void _gettermname();
settimer(baseline);
#if defined(AUTHENTICATION)
/*
* Handle the Authentication option before we do anything else.
*/
send_do(TELOPT_AUTHENTICATION, 1);
while (his_will_wont_is_changing(TELOPT_AUTHENTICATION))
ttloop();
if (his_state_is_will(TELOPT_AUTHENTICATION)) {
retval = auth_wait(name);
}
#endif
send_do(TELOPT_TTYPE, 1);
send_do(TELOPT_TSPEED, 1);
send_do(TELOPT_XDISPLOC, 1);
send_do(TELOPT_NEW_ENVIRON, 1);
send_do(TELOPT_OLD_ENVIRON, 1);
while (
his_will_wont_is_changing(TELOPT_TTYPE) ||
his_will_wont_is_changing(TELOPT_TSPEED) ||
his_will_wont_is_changing(TELOPT_XDISPLOC) ||
his_will_wont_is_changing(TELOPT_NEW_ENVIRON) ||
his_will_wont_is_changing(TELOPT_OLD_ENVIRON)) {
ttloop();
}
if (his_state_is_will(TELOPT_TSPEED)) {
static unsigned char sb[] =
{ IAC, SB, TELOPT_TSPEED, TELQUAL_SEND, IAC, SE };
bcopy(sb, nfrontp, sizeof sb);
nfrontp += sizeof sb;
}
if (his_state_is_will(TELOPT_XDISPLOC)) {
static unsigned char sb[] =
{ IAC, SB, TELOPT_XDISPLOC, TELQUAL_SEND, IAC, SE };
bcopy(sb, nfrontp, sizeof sb);
nfrontp += sizeof sb;
}
if (his_state_is_will(TELOPT_NEW_ENVIRON)) {
static unsigned char sb[] =
{ IAC, SB, TELOPT_NEW_ENVIRON, TELQUAL_SEND, IAC, SE };
bcopy(sb, nfrontp, sizeof sb);
nfrontp += sizeof sb;
}
else if (his_state_is_will(TELOPT_OLD_ENVIRON)) {
static unsigned char sb[] =
{ IAC, SB, TELOPT_OLD_ENVIRON, TELQUAL_SEND, IAC, SE };
bcopy(sb, nfrontp, sizeof sb);
nfrontp += sizeof sb;
}
if (his_state_is_will(TELOPT_TTYPE)) {
bcopy(ttytype_sbbuf, nfrontp, sizeof ttytype_sbbuf);
nfrontp += sizeof ttytype_sbbuf;
}
if (his_state_is_will(TELOPT_TSPEED)) {
while (sequenceIs(tspeedsubopt, baseline))
ttloop();
}
if (his_state_is_will(TELOPT_XDISPLOC)) {
while (sequenceIs(xdisplocsubopt, baseline))
ttloop();
}
if (his_state_is_will(TELOPT_NEW_ENVIRON)) {
while (sequenceIs(environsubopt, baseline))
ttloop();
}
if (his_state_is_will(TELOPT_OLD_ENVIRON)) {
while (sequenceIs(oenvironsubopt, baseline))
ttloop();
}
if (his_state_is_will(TELOPT_TTYPE)) {
char first[256], last[256];
while (sequenceIs(ttypesubopt, baseline))
ttloop();
/*
* If the other side has already disabled the option, then
* we have to just go with what we (might) have already gotten.
*/
if (his_state_is_will(TELOPT_TTYPE) && !terminaltypeok(terminaltype)) {
(void) strncpy(first, terminaltype, sizeof(first)-1);
first[sizeof(first)-1] = '\0';
for(;;) {
/*
* Save the unknown name, and request the next name.
*/
(void) strncpy(last, terminaltype, sizeof(last)-1);
last[sizeof(last)-1] = '\0';
_gettermname();
if (terminaltypeok(terminaltype))
break;
if ((strncmp(last, terminaltype, sizeof(last)) == 0) ||
his_state_is_wont(TELOPT_TTYPE)) {
/*
* We've hit the end. If this is the same as
* the first name, just go with it.
*/
if (strncmp(first, terminaltype, sizeof(first)) == 0)
break;
/*
* Get the terminal name one more time, so that
* RFC1091 compliant telnets will cycle back to
* the start of the list.
*/
_gettermname();
if (strncmp(first, terminaltype, sizeof(first)) != 0) {
(void) strncpy(terminaltype, first, sizeof(terminaltype)-1);
terminaltype[sizeof(terminaltype)-1] = '\0';
}
break;
}
}
}
}
return(retval);
} /* end of getterminaltype */
void
_gettermname()
{
/*
* If the client turned off the option,
* we can't send another request, so we
* just return.
*/
if (his_state_is_wont(TELOPT_TTYPE))
return;
settimer(baseline);
bcopy(ttytype_sbbuf, nfrontp, sizeof ttytype_sbbuf);
nfrontp += sizeof ttytype_sbbuf;
while (sequenceIs(ttypesubopt, baseline))
ttloop();
}
int
terminaltypeok(s)
char *s;
{
char buf[1024];
if (terminaltype == NULL)
return(1);
/*
* tgetent() will return 1 if the type is known, and
* 0 if it is not known. If it returns -1, it couldn't
* open the database. But if we can't open the database,
* it won't help to say we failed, because we won't be
* able to verify anything else. So, we treat -1 like 1.
*/
if (tgetent(buf, s) == 0)
return(0);
return(1);
}
#ifndef MAXHOSTNAMELEN
#define MAXHOSTNAMELEN 64
#endif /* MAXHOSTNAMELEN */
char *hostname;
char host_name[MAXHOSTNAMELEN];
extern void telnet P((int, int, char *));
int level;
char user_name[256];
/*
* Get a pty, scan input lines.
*/
void
doit(who)
struct sockaddr_in *who;
{
int ptynum;
/*
* Find an available pty to use.
*/
#ifndef convex
pty = getpty(&ptynum);
if (pty < 0)
fatal(net, "All network ports in use");
#else
for (;;) {
char *lp;
extern char *line, *getpty();
if ((lp = getpty()) == NULL)
fatal(net, "Out of ptys");
if ((pty = open(lp, 2)) >= 0) {
strcpy(line,lp);
line[5] = 't';
break;
}
}
#endif
#if defined(_SC_CRAY_SECURE_SYS)
/*
* set ttyp line security label
*/
if (secflag) {
char slave_dev[16];
sprintf(tty_dev, "/dev/pty/%03d", ptynum);
if (setdevs(tty_dev, &dv) < 0)
fatal(net, "cannot set pty security");
sprintf(slave_dev, "/dev/ttyp%03d", ptynum);
if (setdevs(slave_dev, &dv) < 0)
fatal(net, "cannot set tty security");
}
#endif /* _SC_CRAY_SECURE_SYS */
/* get name of connected client */
if (realhostname(remote_hostname, sizeof(remote_hostname) - 1,
&who->sin_addr) == HOSTNAME_INVALIDADDR && registerd_host_only)
fatal(net, "Couldn't resolve your address into a host name.\r\n\
Please contact your net administrator");
remote_hostname[sizeof(remote_hostname) - 1] = '\0';
trimdomain(remote_hostname, UT_HOSTSIZE);
if (!isdigit(remote_hostname[0]) && strlen(remote_hostname) > utmp_len)
strncpy(remote_hostname, inet_ntoa(who->sin_addr),
sizeof(remote_hostname) - 1);
(void) gethostname(host_name, sizeof(host_name) - 1);
host_name[sizeof(host_name) - 1] = '\0';
hostname = host_name;
#if defined(AUTHENTICATION)
auth_encrypt_init(hostname, remote_hostname, "TELNETD", 1);
#endif
init_env();
/*
* get terminal type.
*/
*user_name = 0;
level = getterminaltype(user_name);
setenv("TERM", terminaltype ? terminaltype : "network", 1);
#if defined(_SC_CRAY_SECURE_SYS)
if (secflag) {
if (setulvl(dv.dv_actlvl) < 0)
fatal(net,"cannot setulvl()");
if (setucmp(dv.dv_actcmp) < 0)
fatal(net, "cannot setucmp()");
}
#endif /* _SC_CRAY_SECURE_SYS */
telnet(net, pty, remote_hostname); /* begin server process */
/*NOTREACHED*/
} /* end of doit */
#if defined(CRAY2) && defined(UNICOS5) && defined(UNICOS50)
int
Xterm_output(ibufp, obuf, icountp, ocount)
char **ibufp, *obuf;
int *icountp, ocount;
{
int ret;
ret = term_output(*ibufp, obuf, *icountp, ocount);
*ibufp += *icountp;
*icountp = 0;
return(ret);
}
#define term_output Xterm_output
#endif /* defined(CRAY2) && defined(UNICOS5) && defined(UNICOS50) */
/*
* Main loop. Select from pty and network, and
* hand data to telnet receiver finite state machine.
*/
void
telnet(f, p, host)
int f, p;
char *host;
{
int on = 1;
#define TABBUFSIZ 512
char defent[TABBUFSIZ];
char defstrs[TABBUFSIZ];
#undef TABBUFSIZ
char *HE;
char *HN;
char *IM;
char *IF;
char *if_buf;
int if_fd;
struct stat statbuf;
void netflush();
/*
* Initialize the slc mapping table.
*/
get_slc_defaults();
/*
* Do some tests where it is desireable to wait for a response.
* Rather than doing them slowly, one at a time, do them all
* at once.
*/
if (my_state_is_wont(TELOPT_SGA))
send_will(TELOPT_SGA, 1);
/*
* Is the client side a 4.2 (NOT 4.3) system? We need to know this
* because 4.2 clients are unable to deal with TCP urgent data.
*
* To find out, we send out a "DO ECHO". If the remote system
* answers "WILL ECHO" it is probably a 4.2 client, and we note
* that fact ("WILL ECHO" ==> that the client will echo what
* WE, the server, sends it; it does NOT mean that the client will
* echo the terminal input).
*/
send_do(TELOPT_ECHO, 1);
#ifdef LINEMODE
if (his_state_is_wont(TELOPT_LINEMODE)) {
/* Query the peer for linemode support by trying to negotiate
* the linemode option.
*/
linemode = 0;
editmode = 0;
send_do(TELOPT_LINEMODE, 1); /* send do linemode */
}
#endif /* LINEMODE */
/*
* Send along a couple of other options that we wish to negotiate.
*/
send_do(TELOPT_NAWS, 1);
send_will(TELOPT_STATUS, 1);
flowmode = 1; /* default flow control state */
restartany = -1; /* uninitialized... */
send_do(TELOPT_LFLOW, 1);
/*
* Spin, waiting for a response from the DO ECHO. However,
* some REALLY DUMB telnets out there might not respond
* to the DO ECHO. So, we spin looking for NAWS, (most dumb
* telnets so far seem to respond with WONT for a DO that
* they don't understand...) because by the time we get the
* response, it will already have processed the DO ECHO.
* Kludge upon kludge.
*/
while (his_will_wont_is_changing(TELOPT_NAWS))
ttloop();
/*
* But...
* The client might have sent a WILL NAWS as part of its
* startup code; if so, we'll be here before we get the
* response to the DO ECHO. We'll make the assumption
* that any implementation that understands about NAWS
* is a modern enough implementation that it will respond
* to our DO ECHO request; hence we'll do another spin
* waiting for the ECHO option to settle down, which is
* what we wanted to do in the first place...
*/
if (his_want_state_is_will(TELOPT_ECHO) &&
his_state_is_will(TELOPT_NAWS)) {
while (his_will_wont_is_changing(TELOPT_ECHO))
ttloop();
}
/*
* On the off chance that the telnet client is broken and does not
* respond to the DO ECHO we sent, (after all, we did send the
* DO NAWS negotiation after the DO ECHO, and we won't get here
* until a response to the DO NAWS comes back) simulate the
* receipt of a will echo. This will also send a WONT ECHO
* to the client, since we assume that the client failed to
* respond because it believes that it is already in DO ECHO
* mode, which we do not want.
*/
if (his_want_state_is_will(TELOPT_ECHO)) {
DIAG(TD_OPTIONS,
{sprintf(nfrontp, "td: simulating recv\r\n");
nfrontp += strlen(nfrontp);});
willoption(TELOPT_ECHO);
}
/*
* Finally, to clean things up, we turn on our echo. This
* will break stupid 4.2 telnets out of local terminal echo.
*/
if (my_state_is_wont(TELOPT_ECHO))
send_will(TELOPT_ECHO, 1);
#ifndef STREAMSPTY
/*
* Turn on packet mode
*/
(void) ioctl(p, TIOCPKT, (char *)&on);
#endif
#if defined(LINEMODE) && defined(KLUDGELINEMODE)
/*
* Continuing line mode support. If client does not support
* real linemode, attempt to negotiate kludge linemode by sending
* the do timing mark sequence.
*/
if (lmodetype < REAL_LINEMODE)
send_do(TELOPT_TM, 1);
#endif /* defined(LINEMODE) && defined(KLUDGELINEMODE) */
/*
* Call telrcv() once to pick up anything received during
* terminal type negotiation, 4.2/4.3 determination, and
* linemode negotiation.
*/
telrcv();
(void) ioctl(f, FIONBIO, (char *)&on);
(void) ioctl(p, FIONBIO, (char *)&on);
#if defined(CRAY2) && defined(UNICOS5)
init_termdriver(f, p, interrupt, sendbrk);
#endif
#if defined(SO_OOBINLINE)
(void) setsockopt(net, SOL_SOCKET, SO_OOBINLINE,
(char *)&on, sizeof on);
#endif /* defined(SO_OOBINLINE) */
#ifdef SIGTSTP
(void) signal(SIGTSTP, SIG_IGN);
#endif
#ifdef SIGTTOU
/*
* Ignoring SIGTTOU keeps the kernel from blocking us
* in ttioct() in /sys/tty.c.
*/
(void) signal(SIGTTOU, SIG_IGN);
#endif
(void) signal(SIGCHLD, cleanup);
#if defined(CRAY2) && defined(UNICOS5)
/*
* Cray-2 will send a signal when pty modes are changed by slave
* side. Set up signal handler now.
*/
if ((int)signal(SIGUSR1, termstat) < 0)
warn("signal");
else if (ioctl(p, TCSIGME, (char *)SIGUSR1) < 0)
warn("ioctl:TCSIGME");
/*
* Make processing loop check terminal characteristics early on.
*/
termstat();
#endif
#ifdef TIOCNOTTY
{
register int t;
t = open(_PATH_TTY, O_RDWR);
if (t >= 0) {
(void) ioctl(t, TIOCNOTTY, (char *)0);
(void) close(t);
}
}
#endif
#if defined(CRAY) && defined(NEWINIT) && defined(TIOCSCTTY)
(void) setsid();
ioctl(p, TIOCSCTTY, 0);
#endif
/*
* Show banner that getty never gave.
*
* We put the banner in the pty input buffer. This way, it
* gets carriage return null processing, etc., just like all
* other pty --> client data.
*/
#if !defined(CRAY) || !defined(NEWINIT)
if (getenv("USER"))
hostinfo = 0;
#endif
if (getent(defent, "default") == 1) {
char *Getstr();
char *cp=defstrs;
HE = Getstr("he", &cp);
HN = Getstr("hn", &cp);
IM = Getstr("im", &cp);
IF = Getstr("if", &cp);
if (HN && *HN)
(void) strcpy(host_name, HN);
if (IF && (if_fd = open(IF, O_RDONLY, 000)) != -1)
IM = 0;
if (IM == 0)
IM = "";
} else {
IM = DEFAULT_IM;
HE = 0;
}
edithost(HE, host_name);
if (hostinfo && *IM)
putf(IM, ptyibuf2);
else if (IF && if_fd != -1) {
fstat (if_fd, &statbuf);
if_buf = (char *) mmap (0, statbuf.st_size, PROT_READ,
0, if_fd, 0);
putf(if_buf, ptyibuf2);
munmap (if_buf, statbuf.st_size);
close (if_fd);
}
if (pcc)
(void) strncat(ptyibuf2, ptyip, pcc+1);
ptyip = ptyibuf2;
pcc = strlen(ptyip);
#ifdef LINEMODE
/*
* Last check to make sure all our states are correct.
*/
init_termbuf();
localstat();
#endif /* LINEMODE */
DIAG(TD_REPORT,
{sprintf(nfrontp, "td: Entering processing loop\r\n");
nfrontp += strlen(nfrontp);});
/*
* Startup the login process on the slave side of the terminal
* now. We delay this until here to insure option negotiation
* is complete.
*/
startslave(host, level, user_name);
for (;;) {
fd_set ibits, obits, xbits;
register int c;
if (ncc < 0 && pcc < 0)
break;
#if defined(CRAY2) && defined(UNICOS5)
if (needtermstat)
_termstat();
#endif /* defined(CRAY2) && defined(UNICOS5) */
FD_ZERO(&ibits);
FD_ZERO(&obits);
FD_ZERO(&xbits);
/*
* Never look for input if there's still
* stuff in the corresponding output buffer
*/
if (nfrontp - nbackp || pcc > 0) {
FD_SET(f, &obits);
} else {
FD_SET(p, &ibits);
}
if (pfrontp - pbackp || ncc > 0) {
FD_SET(p, &obits);
} else {
FD_SET(f, &ibits);
}
if (!SYNCHing) {
FD_SET(f, &xbits);
}
if ((c = select(16, &ibits, &obits, &xbits,
(struct timeval *)0)) < 1) {
if (c == -1) {
if (errno == EINTR) {
continue;
}
}
sleep(5);
continue;
}
/*
* Any urgent data?
*/
if (FD_ISSET(net, &xbits)) {
SYNCHing = 1;
}
/*
* Something to read from the network...
*/
if (FD_ISSET(net, &ibits)) {
#if !defined(SO_OOBINLINE)
/*
* In 4.2 (and 4.3 beta) systems, the
* OOB indication and data handling in the kernel
* is such that if two separate TCP Urgent requests
* come in, one byte of TCP data will be overlaid.
* This is fatal for Telnet, but we try to live
* with it.
*
* In addition, in 4.2 (and...), a special protocol
* is needed to pick up the TCP Urgent data in
* the correct sequence.
*
* What we do is: if we think we are in urgent
* mode, we look to see if we are "at the mark".
* If we are, we do an OOB receive. If we run
* this twice, we will do the OOB receive twice,
* but the second will fail, since the second
* time we were "at the mark", but there wasn't
* any data there (the kernel doesn't reset
* "at the mark" until we do a normal read).
* Once we've read the OOB data, we go ahead
* and do normal reads.
*
* There is also another problem, which is that
* since the OOB byte we read doesn't put us
* out of OOB state, and since that byte is most
* likely the TELNET DM (data mark), we would
* stay in the TELNET SYNCH (SYNCHing) state.
* So, clocks to the rescue. If we've "just"
* received a DM, then we test for the
* presence of OOB data when the receive OOB
* fails (and AFTER we did the normal mode read
* to clear "at the mark").
*/
if (SYNCHing) {
int atmark;
(void) ioctl(net, SIOCATMARK, (char *)&atmark);
if (atmark) {
ncc = recv(net, netibuf, sizeof (netibuf), MSG_OOB);
if ((ncc == -1) && (errno == EINVAL)) {
ncc = read(net, netibuf, sizeof (netibuf));
if (sequenceIs(didnetreceive, gotDM)) {
SYNCHing = stilloob(net);
}
}
} else {
ncc = read(net, netibuf, sizeof (netibuf));
}
} else {
ncc = read(net, netibuf, sizeof (netibuf));
}
settimer(didnetreceive);
#else /* !defined(SO_OOBINLINE)) */
ncc = read(net, netibuf, sizeof (netibuf));
#endif /* !defined(SO_OOBINLINE)) */
if (ncc < 0 && errno == EWOULDBLOCK)
ncc = 0;
else {
if (ncc <= 0) {
break;
}
netip = netibuf;
}
DIAG((TD_REPORT | TD_NETDATA),
{sprintf(nfrontp, "td: netread %d chars\r\n", ncc);
nfrontp += strlen(nfrontp);});
DIAG(TD_NETDATA, printdata("nd", netip, ncc));
}
/*
* Something to read from the pty...
*/
if (FD_ISSET(p, &ibits)) {
#ifndef STREAMSPTY
pcc = read(p, ptyibuf, BUFSIZ);
#else
pcc = readstream(p, ptyibuf, BUFSIZ);
#endif
/*
* On some systems, if we try to read something
* off the master side before the slave side is
* opened, we get EIO.
*/
if (pcc < 0 && (errno == EWOULDBLOCK ||
#ifdef EAGAIN
errno == EAGAIN ||
#endif
errno == EIO)) {
pcc = 0;
} else {
if (pcc <= 0)
break;
#if !defined(CRAY2) || !defined(UNICOS5)
#ifdef LINEMODE
/*
* If ioctl from pty, pass it through net
*/
if (ptyibuf[0] & TIOCPKT_IOCTL) {
copy_termbuf(ptyibuf+1, pcc-1);
localstat();
pcc = 1;
}
#endif /* LINEMODE */
if (ptyibuf[0] & TIOCPKT_FLUSHWRITE) {
netclear(); /* clear buffer back */
#ifndef NO_URGENT
/*
* There are client telnets on some
* operating systems get screwed up
* royally if we send them urgent
* mode data.
*/
*nfrontp++ = IAC;
*nfrontp++ = DM;
neturg = nfrontp-1; /* off by one XXX */
#endif
}
if (his_state_is_will(TELOPT_LFLOW) &&
(ptyibuf[0] &
(TIOCPKT_NOSTOP|TIOCPKT_DOSTOP))) {
int newflow =
ptyibuf[0] & TIOCPKT_DOSTOP ? 1 : 0;
if (newflow != flowmode) {
flowmode = newflow;
(void) sprintf(nfrontp,
"%c%c%c%c%c%c",
IAC, SB, TELOPT_LFLOW,
flowmode ? LFLOW_ON
: LFLOW_OFF,
IAC, SE);
nfrontp += 6;
}
}
pcc--;
ptyip = ptyibuf+1;
#else /* defined(CRAY2) && defined(UNICOS5) */
if (!uselinemode) {
unpcc = pcc;
unptyip = ptyibuf;
pcc = term_output(&unptyip, ptyibuf2,
&unpcc, BUFSIZ);
ptyip = ptyibuf2;
} else
ptyip = ptyibuf;
#endif /* defined(CRAY2) && defined(UNICOS5) */
}
}
while (pcc > 0) {
if ((&netobuf[BUFSIZ] - nfrontp) < 2)
break;
c = *ptyip++ & 0377, pcc--;
if (c == IAC)
*nfrontp++ = c;
#if defined(CRAY2) && defined(UNICOS5)
else if (c == '\n' &&
my_state_is_wont(TELOPT_BINARY) && newmap)
*nfrontp++ = '\r';
#endif /* defined(CRAY2) && defined(UNICOS5) */
*nfrontp++ = c;
if ((c == '\r') && (my_state_is_wont(TELOPT_BINARY))) {
if (pcc > 0 && ((*ptyip & 0377) == '\n')) {
*nfrontp++ = *ptyip++ & 0377;
pcc--;
} else
*nfrontp++ = '\0';
}
}
#if defined(CRAY2) && defined(UNICOS5)
/*
* If chars were left over from the terminal driver,
* note their existence.
*/
if (!uselinemode && unpcc) {
pcc = unpcc;
unpcc = 0;
ptyip = unptyip;
}
#endif /* defined(CRAY2) && defined(UNICOS5) */
if (FD_ISSET(f, &obits) && (nfrontp - nbackp) > 0)
netflush();
if (ncc > 0)
telrcv();
if (FD_ISSET(p, &obits) && (pfrontp - pbackp) > 0)
ptyflush();
}
cleanup(0);
} /* end of telnet */
#ifndef TCSIG
# ifdef TIOCSIG
# define TCSIG TIOCSIG
# endif
#endif
#ifdef STREAMSPTY
int flowison = -1; /* current state of flow: -1 is unknown */
int readstream(p, ibuf, bufsize)
int p;
char *ibuf;
int bufsize;
{
int flags = 0;
int ret = 0;
struct termios *tsp;
struct termio *tp;
struct iocblk *ip;
char vstop, vstart;
int ixon;
int newflow;
strbufc.maxlen = BUFSIZ;
strbufc.buf = (char *)ctlbuf;
strbufd.maxlen = bufsize-1;
strbufd.len = 0;
strbufd.buf = ibuf+1;
ibuf[0] = 0;
ret = getmsg(p, &strbufc, &strbufd, &flags);
if (ret < 0) /* error of some sort -- probably EAGAIN */
return(-1);
if (strbufc.len <= 0 || ctlbuf[0] == M_DATA) {
/* data message */
if (strbufd.len > 0) { /* real data */
return(strbufd.len + 1); /* count header char */
} else {
/* nothing there */
errno = EAGAIN;
return(-1);
}
}
/*
* It's a control message. Return 1, to look at the flag we set
*/
switch (ctlbuf[0]) {
case M_FLUSH:
if (ibuf[1] & FLUSHW)
ibuf[0] = TIOCPKT_FLUSHWRITE;
return(1);
case M_IOCTL:
ip = (struct iocblk *) (ibuf+1);
switch (ip->ioc_cmd) {
case TCSETS:
case TCSETSW:
case TCSETSF:
tsp = (struct termios *)
(ibuf+1 + sizeof(struct iocblk));
vstop = tsp->c_cc[VSTOP];
vstart = tsp->c_cc[VSTART];
ixon = tsp->c_iflag & IXON;
break;
case TCSETA:
case TCSETAW:
case TCSETAF:
tp = (struct termio *) (ibuf+1 + sizeof(struct iocblk));
vstop = tp->c_cc[VSTOP];
vstart = tp->c_cc[VSTART];
ixon = tp->c_iflag & IXON;
break;
default:
errno = EAGAIN;
return(-1);
}
newflow = (ixon && (vstart == 021) && (vstop == 023)) ? 1 : 0;
if (newflow != flowison) { /* it's a change */
flowison = newflow;
ibuf[0] = newflow ? TIOCPKT_DOSTOP : TIOCPKT_NOSTOP;
return(1);
}
}
/* nothing worth doing anything about */
errno = EAGAIN;
return(-1);
}
#endif /* STREAMSPTY */
/*
* Send interrupt to process on other side of pty.
* If it is in raw mode, just write NULL;
* otherwise, write intr char.
*/
void
interrupt()
{
ptyflush(); /* half-hearted */
#ifdef TCSIG
(void) ioctl(pty, TCSIG, (char *)SIGINT);
#else /* TCSIG */
init_termbuf();
*pfrontp++ = slctab[SLC_IP].sptr ?
(unsigned char)*slctab[SLC_IP].sptr : '\177';
#endif /* TCSIG */
}
/*
* Send quit to process on other side of pty.
* If it is in raw mode, just write NULL;
* otherwise, write quit char.
*/
void
sendbrk()
{
ptyflush(); /* half-hearted */
#ifdef TCSIG
(void) ioctl(pty, TCSIG, (char *)SIGQUIT);
#else /* TCSIG */
init_termbuf();
*pfrontp++ = slctab[SLC_ABORT].sptr ?
(unsigned char)*slctab[SLC_ABORT].sptr : '\034';
#endif /* TCSIG */
}
void
sendsusp()
{
#ifdef SIGTSTP
ptyflush(); /* half-hearted */
# ifdef TCSIG
(void) ioctl(pty, TCSIG, (char *)SIGTSTP);
# else /* TCSIG */
*pfrontp++ = slctab[SLC_SUSP].sptr ?
(unsigned char)*slctab[SLC_SUSP].sptr : '\032';
# endif /* TCSIG */
#endif /* SIGTSTP */
}
/*
* When we get an AYT, if ^T is enabled, use that. Otherwise,
* just send back "[Yes]".
*/
void
recv_ayt()
{
#if defined(SIGINFO) && defined(TCSIG)
if (slctab[SLC_AYT].sptr && *slctab[SLC_AYT].sptr != _POSIX_VDISABLE) {
(void) ioctl(pty, TCSIG, (char *)SIGINFO);
return;
}
#endif
(void) strcpy(nfrontp, "\r\n[Yes]\r\n");
nfrontp += 9;
}
void
doeof()
{
init_termbuf();
#if defined(LINEMODE) && defined(USE_TERMIO) && (VEOF == VMIN)
if (!tty_isediting()) {
extern char oldeofc;
*pfrontp++ = oldeofc;
return;
}
#endif
*pfrontp++ = slctab[SLC_EOF].sptr ?
(unsigned char)*slctab[SLC_EOF].sptr : '\004';
}