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freebsd/libexec/getty/main.c
Edward Tomasz Napierala 170430d505 Prevent getty(8) from looping indefinitely if the device node doesn't
exist. This behaviour makes no sense for eg USB serial adapters, or
USB device-side serial templates.

This mostly reverts to pre-r135941 behaviour.

Reviewed by:	imp@
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D14198
2018-02-25 20:15:06 +00:00

820 lines
18 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1980, 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. 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) 1980, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)from: main.c 8.1 (Berkeley) 6/20/93";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/ttydefaults.h>
#include <sys/utsname.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <locale.h>
#include <libutil.h>
#include <setjmp.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <termios.h>
#include <time.h>
#include <unistd.h>
#include "gettytab.h"
#include "extern.h"
#include "pathnames.h"
/*
* Set the amount of running time that getty should accumulate
* before deciding that something is wrong and exit.
*/
#define GETTY_TIMEOUT 60 /* seconds */
#undef CTRL
#define CTRL(x) (x&037)
/* defines for auto detection of incoming PPP calls (->PAP/CHAP) */
#define PPP_FRAME 0x7e /* PPP Framing character */
#define PPP_STATION 0xff /* "All Station" character */
#define PPP_ESCAPE 0x7d /* Escape Character */
#define PPP_CONTROL 0x03 /* PPP Control Field */
#define PPP_CONTROL_ESCAPED 0x23 /* PPP Control Field, escaped */
#define PPP_LCP_HI 0xc0 /* LCP protocol - high byte */
#define PPP_LCP_LOW 0x21 /* LCP protocol - low byte */
/* original mode; flags've been reset using values from <sys/ttydefaults.h> */
struct termios omode;
/* current mode */
struct termios tmode;
static int crmod, digit, lower, upper;
char hostname[MAXHOSTNAMELEN];
static char name[MAXLOGNAME*3];
static char dev[] = _PATH_DEV;
static char ttyn[32];
#define OBUFSIZ 128
#define TABBUFSIZ 512
static char defent[TABBUFSIZ];
static char tabent[TABBUFSIZ];
static const char *tname;
static char *env[128];
static char partab[] = {
0001,0201,0201,0001,0201,0001,0001,0201,
0202,0004,0003,0205,0005,0206,0201,0001,
0201,0001,0001,0201,0001,0201,0201,0001,
0001,0201,0201,0001,0201,0001,0001,0201,
0200,0000,0000,0200,0000,0200,0200,0000,
0000,0200,0200,0000,0200,0000,0000,0200,
0000,0200,0200,0000,0200,0000,0000,0200,
0200,0000,0000,0200,0000,0200,0200,0000,
0200,0000,0000,0200,0000,0200,0200,0000,
0000,0200,0200,0000,0200,0000,0000,0200,
0000,0200,0200,0000,0200,0000,0000,0200,
0200,0000,0000,0200,0000,0200,0200,0000,
0000,0200,0200,0000,0200,0000,0000,0200,
0200,0000,0000,0200,0000,0200,0200,0000,
0200,0000,0000,0200,0000,0200,0200,0000,
0000,0200,0200,0000,0200,0000,0000,0201
};
#define ERASE tmode.c_cc[VERASE]
#define KILL tmode.c_cc[VKILL]
#define EOT tmode.c_cc[VEOF]
#define puts Gputs
static void defttymode(void);
static void dingdong(int);
static void dogettytab(void);
static int getname(void);
static void interrupt(int);
static void oflush(void);
static void prompt(void);
static void putchr(int);
static void putf(const char *);
static void putpad(const char *);
static void puts(const char *);
static void timeoverrun(int);
static char *get_line(int);
static void setttymode(int);
static int opentty(const char *, int);
static jmp_buf timeout;
static void
dingdong(int signo __unused)
{
alarm(0);
longjmp(timeout, 1);
}
static jmp_buf intrupt;
static void
interrupt(int signo __unused)
{
longjmp(intrupt, 1);
}
/*
* Action to take when getty is running too long.
*/
static void
timeoverrun(int signo __unused)
{
syslog(LOG_ERR, "getty exiting due to excessive running time");
exit(1);
}
int
main(int argc, char *argv[])
{
int first_sleep = 1, first_time = 1;
struct rlimit limit;
int rval;
signal(SIGINT, SIG_IGN);
signal(SIGQUIT, SIG_IGN);
openlog("getty", LOG_CONS|LOG_PID, LOG_AUTH);
gethostname(hostname, sizeof(hostname) - 1);
hostname[sizeof(hostname) - 1] = '\0';
if (hostname[0] == '\0')
strcpy(hostname, "Amnesiac");
/*
* Limit running time to deal with broken or dead lines.
*/
(void)signal(SIGXCPU, timeoverrun);
limit.rlim_max = RLIM_INFINITY;
limit.rlim_cur = GETTY_TIMEOUT;
(void)setrlimit(RLIMIT_CPU, &limit);
gettable("default", defent);
gendefaults();
tname = "default";
if (argc > 1)
tname = argv[1];
/*
* The following is a work around for vhangup interactions
* which cause great problems getting window systems started.
* If the tty line is "-", we do the old style getty presuming
* that the file descriptors are already set up for us.
* J. Gettys - MIT Project Athena.
*/
if (argc <= 2 || strcmp(argv[2], "-") == 0)
strcpy(ttyn, ttyname(STDIN_FILENO));
else {
strcpy(ttyn, dev);
strncat(ttyn, argv[2], sizeof(ttyn)-sizeof(dev));
if (strcmp(argv[0], "+") != 0) {
chown(ttyn, 0, 0);
chmod(ttyn, 0600);
revoke(ttyn);
/*
* Do the first scan through gettytab.
* Terminal mode parameters will be wrong until
* defttymode() called, but they're irrelevant for
* the initial setup of the terminal device.
*/
dogettytab();
/*
* Init or answer modem sequence has been specified.
*/
if (IC || AC) {
if (!opentty(ttyn, O_RDWR|O_NONBLOCK))
exit(1);
defttymode();
setttymode(1);
}
if (IC) {
if (getty_chat(IC, CT, DC) > 0) {
syslog(LOG_ERR, "modem init problem on %s", ttyn);
(void)tcsetattr(STDIN_FILENO, TCSANOW, &tmode);
exit(1);
}
}
if (AC) {
fd_set rfds;
struct timeval to;
int i;
FD_ZERO(&rfds);
FD_SET(0, &rfds);
to.tv_sec = RT;
to.tv_usec = 0;
i = select(32, &rfds, NULL, NULL, RT ? &to : NULL);
if (i < 0) {
syslog(LOG_ERR, "select %s: %m", ttyn);
} else if (i == 0) {
syslog(LOG_NOTICE, "recycle tty %s", ttyn);
(void)tcsetattr(STDIN_FILENO, TCSANOW, &tmode);
exit(0); /* recycle for init */
}
i = getty_chat(AC, CT, DC);
if (i > 0) {
syslog(LOG_ERR, "modem answer problem on %s", ttyn);
(void)tcsetattr(STDIN_FILENO, TCSANOW, &tmode);
exit(1);
}
} else { /* maybe blocking open */
if (!opentty(ttyn, O_RDWR | (NC ? O_NONBLOCK : 0 )))
exit(1);
}
}
}
defttymode();
for (;;) {
/*
* if a delay was specified then sleep for that
* number of seconds before writing the initial prompt
*/
if (first_sleep && DE) {
sleep(DE);
/* remove any noise */
(void)tcflush(STDIN_FILENO, TCIOFLUSH);
}
first_sleep = 0;
setttymode(0);
if (AB) {
tname = autobaud();
dogettytab();
continue;
}
if (PS) {
tname = portselector();
dogettytab();
continue;
}
if (CL && *CL)
putpad(CL);
edithost(HE);
/* if this is the first time through this, and an
issue file has been given, then send it */
if (first_time && IF) {
int fd;
if ((fd = open(IF, O_RDONLY)) != -1) {
char * cp;
while ((cp = get_line(fd)) != NULL) {
putf(cp);
}
close(fd);
}
}
first_time = 0;
if (IMP && *IMP && !(PL && PP))
system(IMP);
if (IM && *IM && !(PL && PP))
putf(IM);
if (setjmp(timeout)) {
cfsetispeed(&tmode, B0);
cfsetospeed(&tmode, B0);
(void)tcsetattr(STDIN_FILENO, TCSANOW, &tmode);
exit(1);
}
if (TO) {
signal(SIGALRM, dingdong);
alarm(TO);
}
rval = 0;
if (AL) {
const char *p = AL;
char *q = name;
while (*p && q < &name[sizeof name - 1]) {
if (isupper(*p))
upper = 1;
else if (islower(*p))
lower = 1;
else if (isdigit(*p))
digit = 1;
*q++ = *p++;
}
} else if (!(PL && PP))
rval = getname();
if (rval == 2 || (PL && PP)) {
oflush();
alarm(0);
limit.rlim_max = RLIM_INFINITY;
limit.rlim_cur = RLIM_INFINITY;
(void)setrlimit(RLIMIT_CPU, &limit);
execle(PP, "ppplogin", ttyn, (char *) 0, env);
syslog(LOG_ERR, "%s: %m", PP);
exit(1);
} else if (rval || AL) {
int i;
oflush();
alarm(0);
signal(SIGALRM, SIG_DFL);
if (name[0] == '\0')
continue;
if (name[0] == '-') {
puts("user names may not start with '-'.");
continue;
}
if (!(upper || lower || digit)) {
if (AL) {
syslog(LOG_ERR,
"invalid auto-login name: %s", AL);
exit(1);
} else
continue;
}
set_flags(2);
if (crmod) {
tmode.c_iflag |= ICRNL;
tmode.c_oflag |= ONLCR;
}
#if REALLY_OLD_TTYS
if (upper || UC)
tmode.sg_flags |= LCASE;
if (lower || LC)
tmode.sg_flags &= ~LCASE;
#endif
if (tcsetattr(STDIN_FILENO, TCSANOW, &tmode) < 0) {
syslog(LOG_ERR, "tcsetattr %s: %m", ttyn);
exit(1);
}
signal(SIGINT, SIG_DFL);
for (i = 0; environ[i] != (char *)0; i++)
env[i] = environ[i];
makeenv(&env[i]);
limit.rlim_max = RLIM_INFINITY;
limit.rlim_cur = RLIM_INFINITY;
(void)setrlimit(RLIMIT_CPU, &limit);
execle(LO, "login", AL ? "-fp" : "-p", name,
(char *) 0, env);
syslog(LOG_ERR, "%s: %m", LO);
exit(1);
}
alarm(0);
signal(SIGALRM, SIG_DFL);
signal(SIGINT, SIG_IGN);
if (NX && *NX) {
tname = NX;
dogettytab();
}
}
}
static int
opentty(const char *tty, int flags)
{
int failopenlogged = 0, i, saved_errno;
while ((i = open(tty, flags)) == -1)
{
saved_errno = errno;
if (!failopenlogged) {
syslog(LOG_ERR, "open %s: %m", tty);
failopenlogged = 1;
}
if (saved_errno == ENOENT)
return 0;
sleep(60);
}
if (login_tty(i) < 0) {
if (daemon(0,0) < 0) {
syslog(LOG_ERR,"daemon: %m");
close(i);
return 0;
}
if (login_tty(i) < 0) {
syslog(LOG_ERR, "login_tty %s: %m", tty);
close(i);
return 0;
}
}
return 1;
}
static void
defttymode(void)
{
struct termios def;
/* Start with default tty settings. */
if (tcgetattr(STDIN_FILENO, &tmode) < 0) {
syslog(LOG_ERR, "tcgetattr %s: %m", ttyn);
exit(1);
}
omode = tmode; /* fill c_cc for dogettytab() */
dogettytab();
/*
* Don't rely on the driver too much, and initialize crucial
* things according to <sys/ttydefaults.h>. Avoid clobbering
* the c_cc[] settings however, the console drivers might wish
* to leave their idea of the preferred VERASE key value
* there.
*/
cfmakesane(&def);
tmode.c_iflag = def.c_iflag;
tmode.c_oflag = def.c_oflag;
tmode.c_lflag = def.c_lflag;
tmode.c_cflag = def.c_cflag;
if (NC)
tmode.c_cflag |= CLOCAL;
omode = tmode;
}
static void
setttymode(int raw)
{
int off = 0;
(void)tcflush(STDIN_FILENO, TCIOFLUSH); /* clear out the crap */
ioctl(STDIN_FILENO, FIONBIO, &off); /* turn off non-blocking mode */
ioctl(STDIN_FILENO, FIOASYNC, &off); /* ditto for async mode */
if (IS)
cfsetispeed(&tmode, speed(IS));
else if (SP)
cfsetispeed(&tmode, speed(SP));
if (OS)
cfsetospeed(&tmode, speed(OS));
else if (SP)
cfsetospeed(&tmode, speed(SP));
set_flags(0);
setchars();
if (raw)
cfmakeraw(&tmode);
if (tcsetattr(STDIN_FILENO, TCSANOW, &tmode) < 0) {
syslog(LOG_ERR, "tcsetattr %s: %m", ttyn);
exit(1);
}
}
static int
getname(void)
{
int c;
char *np;
unsigned char cs;
int ppp_state = 0;
int ppp_connection = 0;
/*
* Interrupt may happen if we use CBREAK mode
*/
if (setjmp(intrupt)) {
signal(SIGINT, SIG_IGN);
return (0);
}
signal(SIGINT, interrupt);
set_flags(1);
prompt();
oflush();
if (PF > 0) {
sleep(PF);
PF = 0;
}
if (tcsetattr(STDIN_FILENO, TCSANOW, &tmode) < 0) {
syslog(LOG_ERR, "%s: %m", ttyn);
exit(1);
}
crmod = digit = lower = upper = 0;
np = name;
for (;;) {
oflush();
if (read(STDIN_FILENO, &cs, 1) <= 0)
exit(0);
if ((c = cs&0177) == 0)
return (0);
/* PPP detection state machine..
Look for sequences:
PPP_FRAME, PPP_STATION, PPP_ESCAPE, PPP_CONTROL_ESCAPED or
PPP_FRAME, PPP_STATION, PPP_CONTROL (deviant from RFC)
See RFC1662.
Derived from code from Michael Hancock, <michaelh@cet.co.jp>
and Erik 'PPP' Olson, <eriko@wrq.com>
*/
if (PP && (cs == PPP_FRAME)) {
ppp_state = 1;
} else if (ppp_state == 1 && cs == PPP_STATION) {
ppp_state = 2;
} else if (ppp_state == 2 && cs == PPP_ESCAPE) {
ppp_state = 3;
} else if ((ppp_state == 2 && cs == PPP_CONTROL)
|| (ppp_state == 3 && cs == PPP_CONTROL_ESCAPED)) {
ppp_state = 4;
} else if (ppp_state == 4 && cs == PPP_LCP_HI) {
ppp_state = 5;
} else if (ppp_state == 5 && cs == PPP_LCP_LOW) {
ppp_connection = 1;
break;
} else {
ppp_state = 0;
}
if (c == EOT || c == CTRL('d'))
exit(0);
if (c == '\r' || c == '\n' || np >= &name[sizeof name-1]) {
putf("\r\n");
break;
}
if (islower(c))
lower = 1;
else if (isupper(c))
upper = 1;
else if (c == ERASE || c == '\b' || c == 0177) {
if (np > name) {
np--;
if (cfgetospeed(&tmode) >= 1200)
puts("\b \b");
else
putchr(cs);
}
continue;
} else if (c == KILL || c == CTRL('u')) {
putchr('\r');
if (cfgetospeed(&tmode) < 1200)
putchr('\n');
/* this is the way they do it down under ... */
else if (np > name)
puts(" \r");
prompt();
digit = lower = upper = 0;
np = name;
continue;
} else if (isdigit(c))
digit = 1;
if (IG && (c <= ' ' || c > 0176))
continue;
*np++ = c;
putchr(cs);
}
signal(SIGINT, SIG_IGN);
*np = 0;
if (c == '\r')
crmod = 1;
if ((upper && !lower && !LC) || UC)
for (np = name; *np; np++)
if (isupper(*np))
*np = tolower(*np);
return (1 + ppp_connection);
}
static void
putpad(const char *s)
{
int pad = 0;
speed_t ospeed = cfgetospeed(&tmode);
if (isdigit(*s)) {
while (isdigit(*s)) {
pad *= 10;
pad += *s++ - '0';
}
pad *= 10;
if (*s == '.' && isdigit(s[1])) {
pad += s[1] - '0';
s += 2;
}
}
puts(s);
/*
* If no delay needed, or output speed is
* not comprehensible, then don't try to delay.
*/
if (pad == 0 || ospeed <= 0)
return;
/*
* Round up by a half a character frame, and then do the delay.
* Too bad there are no user program accessible programmed delays.
* Transmitting pad characters slows many terminals down and also
* loads the system.
*/
pad = (pad * ospeed + 50000) / 100000;
while (pad--)
putchr(*PC);
}
static void
puts(const char *s)
{
while (*s)
putchr(*s++);
}
static char outbuf[OBUFSIZ];
static int obufcnt = 0;
static void
putchr(int cc)
{
char c;
c = cc;
if (!NP) {
c |= partab[c&0177] & 0200;
if (OP)
c ^= 0200;
}
if (!UB) {
outbuf[obufcnt++] = c;
if (obufcnt >= OBUFSIZ)
oflush();
} else
write(STDOUT_FILENO, &c, 1);
}
static void
oflush(void)
{
if (obufcnt)
write(STDOUT_FILENO, outbuf, obufcnt);
obufcnt = 0;
}
static void
prompt(void)
{
putf(LM);
if (CO)
putchr('\n');
}
static char *
get_line(int fd)
{
size_t i = 0;
static char linebuf[512];
/*
* This is certainly slow, but it avoids having to include
* stdio.h unnecessarily. Issue files should be small anyway.
*/
while (i < (sizeof linebuf - 3) && read(fd, linebuf+i, 1)==1) {
if (linebuf[i] == '\n') {
/* Don't rely on newline mode, assume raw */
linebuf[i++] = '\r';
linebuf[i++] = '\n';
linebuf[i] = '\0';
return linebuf;
}
++i;
}
linebuf[i] = '\0';
return i ? linebuf : 0;
}
static void
putf(const char *cp)
{
time_t t;
char *slash, db[100];
static struct utsname kerninfo;
if (!*kerninfo.sysname)
uname(&kerninfo);
while (*cp) {
if (*cp != '%') {
putchr(*cp++);
continue;
}
switch (*++cp) {
case 't':
slash = strrchr(ttyn, '/');
if (slash == (char *) 0)
puts(ttyn);
else
puts(&slash[1]);
break;
case 'h':
puts(editedhost);
break;
case 'd': {
t = (time_t)0;
(void)time(&t);
if (Lo)
(void)setlocale(LC_TIME, Lo);
(void)strftime(db, sizeof(db), DF, localtime(&t));
puts(db);
break;
case 's':
puts(kerninfo.sysname);
break;
case 'm':
puts(kerninfo.machine);
break;
case 'r':
puts(kerninfo.release);
break;
case 'v':
puts(kerninfo.version);
break;
}
case '%':
putchr('%');
break;
}
cp++;
}
}
/*
* Read a gettytab database entry and perform necessary quirks.
*/
static void
dogettytab(void)
{
/* Read the database entry. */
gettable(tname, tabent);
/*
* Avoid inheriting the parity values from the default entry
* if any of them is set in the current entry.
* Mixing different parity settings is unreasonable.
*/
if (OPset || EPset || APset || NPset)
OPset = EPset = APset = NPset = 1;
/* Fill in default values for unset capabilities. */
setdefaults();
}