emo/busybox
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
087b9d640e
busybox/loginutils/getty.c

967 lines
25 KiB
C
Raw Blame History

/* vi: set sw=4 ts=4: */
/* agetty.c - another getty program for Linux. By W. Z. Venema 1989
Ported to Linux by Peter Orbaek <poe@daimi.aau.dk>
This program is freely distributable. The entire man-page used to
be here. Now read the real man-page agetty.8 instead.
-f option added by Eric Rasmussen <ear@usfirst.org> - 12/28/95
1999-02-22 Arkadiusz Mi¶kiewicz <misiek@misiek.eu.org>
- added Native Language Support
1999-05-05 Thorsten Kranzkowski <dl8bcu@gmx.net>
- enable hardware flow control before displaying /etc/issue
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/ioctl.h>
#include <errno.h>
#include <sys/stat.h>
#include <signal.h>
#include <fcntl.h>
#include <stdarg.h>
#include <ctype.h>
#include <getopt.h>
#include <termios.h>
#include "busybox.h"
#ifdef CONFIG_FEATURE_UTMP
#include <utmp.h>
#endif
#define _PATH_LOGIN "/bin/login"
/* If USE_SYSLOG is undefined all diagnostics go directly to /dev/console. */
#ifdef CONFIG_SYSLOGD
#include <sys/param.h>
#include <syslog.h>
#endif
/*
* Some heuristics to find out what environment we are in: if it is not
* System V, assume it is SunOS 4.
*/
#ifdef LOGIN_PROCESS /* defined in System V utmp.h */
#define SYSV_STYLE /* select System V style getty */
#ifdef CONFIG_FEATURE_WTMP
extern void updwtmp(const char *filename, const struct utmp *ut);
#endif
#endif /* LOGIN_PROCESS */
/*
* Things you may want to modify.
*
* You may disagree with the default line-editing etc. characters defined
* below. Note, however, that DEL cannot be used for interrupt generation
* and for line editing at the same time.
*/
#ifdef SYSV_STYLE
#include <sys/utsname.h>
#include <time.h>
#endif
/* If ISSUE is not defined, agetty will never display the contents of the
* /etc/issue file. You will not want to spit out large "issue" files at the
* wrong baud rate.
*/
#define ISSUE "/etc/issue" /* displayed before the login prompt */
/* Some shorthands for control characters. */
#define CTL(x) (x ^ 0100) /* Assumes ASCII dialect */
#define CR CTL('M') /* carriage return */
#define NL CTL('J') /* line feed */
#define BS CTL('H') /* back space */
#define DEL CTL('?') /* delete */
/* Defaults for line-editing etc. characters; you may want to change this. */
#define DEF_ERASE DEL /* default erase character */
#define DEF_INTR CTL('C') /* default interrupt character */
#define DEF_QUIT CTL('\\') /* default quit char */
#define DEF_KILL CTL('U') /* default kill char */
#define DEF_EOF CTL('D') /* default EOF char */
#define DEF_EOL '\n'
#define DEF_SWITCH 0 /* default switch char */
/*
* SunOS 4.1.1 termio is broken. We must use the termios stuff instead,
* because the termio -> termios translation does not clear the termios
* CIBAUD bits. Therefore, the tty driver would sometimes report that input
* baud rate != output baud rate. I did not notice that problem with SunOS
* 4.1. We will use termios where available, and termio otherwise.
*/
/* linux 0.12 termio is broken too, if we use it c_cc[VERASE] isn't set
properly, but all is well if we use termios?! */
#ifdef TCGETS
#undef TCGETA
#undef TCSETA
#undef TCSETAW
#define termio termios
#define TCGETA TCGETS
#define TCSETA TCSETS
#define TCSETAW TCSETSW
#endif
/*
* When multiple baud rates are specified on the command line, the first one
* we will try is the first one specified.
*/
#define FIRST_SPEED 0
/* Storage for command-line options. */
#define MAX_SPEED 10 /* max. nr. of baud rates */
struct options {
int flags; /* toggle switches, see below */
int timeout; /* time-out period */
char *login; /* login program */
char *tty; /* name of tty */
char *initstring; /* modem init string */
char *issue; /* alternative issue file */
int numspeed; /* number of baud rates to try */
int speeds[MAX_SPEED]; /* baud rates to be tried */
};
static const char opt_string[] = "I:LH:f:hil:mt:wn";
#define F_INITSTRING (1<<0) /* initstring is set */
#define F_LOCAL (1<<1) /* force local */
#define F_FAKEHOST (1<<2) /* force fakehost */
#define F_CUSTISSUE (1<<3) /* give alternative issue file */
#define F_RTSCTS (1<<4) /* enable RTS/CTS flow control */
#define F_ISSUE (1<<5) /* display /etc/issue */
#define F_LOGIN (1<<6) /* non-default login program */
#define F_PARSE (1<<7) /* process modem status messages */
#define F_TIMEOUT (1<<8) /* time out */
#define F_WAITCRLF (1<<9) /* wait for CR or LF */
#define F_NOPROMPT (1<<10) /* don't ask for login name! */
/* Storage for things detected while the login name was read. */
struct chardata {
int erase; /* erase character */
int kill; /* kill character */
int eol; /* end-of-line character */
int parity; /* what parity did we see */
int capslock; /* upper case without lower case */
};
/* Initial values for the above. */
static struct chardata init_chardata = {
DEF_ERASE, /* default erase character */
DEF_KILL, /* default kill character */
13, /* default eol char */
0, /* space parity */
0, /* no capslock */
};
#if 0
struct Speedtab {
long speed;
int code;
};
static struct Speedtab speedtab[] = {
{50, B50},
{75, B75},
{110, B110},
{134, B134},
{150, B150},
{200, B200},
{300, B300},
{600, B600},
{1200, B1200},
{1800, B1800},
{2400, B2400},
{4800, B4800},
{9600, B9600},
#ifdef B19200
{19200, B19200},
#endif
#ifdef B38400
{38400, B38400},
#endif
#ifdef EXTA
{19200, EXTA},
#endif
#ifdef EXTB
{38400, EXTB},
#endif
#ifdef B57600
{57600, B57600},
#endif
#ifdef B115200
{115200, B115200},
#endif
#ifdef B230400
{230400, B230400},
#endif
{0, 0},
};
#endif
#ifdef SYSV_STYLE
#ifdef CONFIG_FEATURE_UTMP
static void update_utmp(char *line);
#endif
#endif
/* The following is used for understandable diagnostics. */
/* Fake hostname for ut_host specified on command line. */
static char *fakehost = NULL;
/* ... */
#ifdef DEBUGGING
#define debug(s) fprintf(dbf,s); fflush(dbf)
#define DEBUGTERM "/dev/ttyp0"
FILE *dbf;
#else
#define debug(s) /* nothing */
#endif
/*
* output error messages
*/
static void error(const char *fmt, ...) ATTRIBUTE_NORETURN;
static void error(const char *fmt, ...)
{
va_list va_alist;
char buf[256];
#ifdef CONFIG_SYSLOGD
va_start(va_alist, fmt);
vsnprintf(buf, sizeof(buf), fmt, va_alist);
openlog(bb_applet_name, 0, LOG_AUTH);
syslog(LOG_ERR, "%s", buf);
closelog();
#else
int fd;
size_t l;
snprintf(buf, sizeof(buf), "%s: ", bb_applet_name);
l = strlen(buf);
va_start(va_alist, fmt);
vsnprintf(buf + l, sizeof(buf) - l, fmt, va_alist);
l = strlen(buf);
/* truncate if need */
if((l + 3) > sizeof(buf))
l = sizeof(buf) - 3;
/* add \r\n always */
buf[l++] = '\r';
buf[l++] = '\n';
buf[l] = 0;
if ((fd = open("/dev/console", 1)) >= 0) {
write(fd, buf, l);
close(fd);
}
#endif
va_end(va_alist);
(void) sleep((unsigned) 10); /* be kind to init(8) */
exit(1);
}
/* bcode - convert speed string to speed code; return 0 on failure */
static int bcode(const char *s)
{
int r;
unsigned long value;
if (safe_strtoul((char *)s, &value)) {
return -1;
}
if ((r = tty_value_to_baud(value)) > 0) {
return r;
}
return 0;
}
/* parse_speeds - parse alternate baud rates */
static void parse_speeds(struct options *op, char *arg)
{
char *cp;
debug("entered parse_speeds\n");
for (cp = strtok(arg, ","); cp != 0; cp = strtok((char *) 0, ",")) {
if ((op->speeds[op->numspeed++] = bcode(cp)) <= 0)
error("bad speed: %s", cp);
if (op->numspeed > MAX_SPEED)
error("too many alternate speeds");
}
debug("exiting parsespeeds\n");
}
/* parse-args - parse command-line arguments */
static void parse_args(int argc, char **argv, struct options *op)
{
char *ts;
op->flags = bb_getopt_ulflags(argc, argv, opt_string,
&(op->initstring), &fakehost, &(op->issue),
&(op->login), &ts);
if(op->flags & F_INITSTRING) {
const char *p = op->initstring;
char *q;
q = op->initstring = bb_xstrdup(op->initstring);
/* copy optarg into op->initstring decoding \ddd
octal codes into chars */
while (*p) {
if (*p == '\\') {
p++;
*q++ = bb_process_escape_sequence(&p);
} else {
*q++ = *p++;
}
}
*q = '\0';
}
op->flags ^= F_ISSUE; /* revert flag show /etc/issue */
if(op->flags & F_TIMEOUT) {
if ((op->timeout = atoi(ts)) <= 0)
error("bad timeout value: %s", ts);
}
debug("after getopt loop\n");
if (argc < optind + 2) /* check parameter count */
bb_show_usage();
/* we loosen up a bit and accept both "baudrate tty" and "tty baudrate" */
if ('0' <= argv[optind][0] && argv[optind][0] <= '9') {
/* a number first, assume it's a speed (BSD style) */
parse_speeds(op, argv[optind++]); /* baud rate(s) */
op->tty = argv[optind]; /* tty name */
} else {
op->tty = argv[optind++]; /* tty name */
parse_speeds(op, argv[optind]); /* baud rate(s) */
}
optind++;
if (argc > optind && argv[optind])
setenv("TERM", argv[optind], 1);
debug("exiting parseargs\n");
}
/* open_tty - set up tty as standard { input, output, error } */
static void open_tty(char *tty, struct termio *tp, int local)
{
int chdir_to_root = 0;
/* Set up new standard input, unless we are given an already opened port. */
if (strcmp(tty, "-")) {
struct stat st;
int fd;
/* Sanity checks... */
if (chdir("/dev"))
error("/dev: chdir() failed: %m");
chdir_to_root = 1;
if (stat(tty, &st) < 0)
error("/dev/%s: %m", tty);
if ((st.st_mode & S_IFMT) != S_IFCHR)
error("/dev/%s: not a character device", tty);
/* Open the tty as standard input. */
close(0);
debug("open(2)\n");
fd = open(tty, O_RDWR | O_NONBLOCK, 0);
if (fd != 0)
error("/dev/%s: cannot open as standard input: %m", tty);
} else {
/*
* Standard input should already be connected to an open port. Make
* sure it is open for read/write.
*/
if ((fcntl(0, F_GETFL, 0) & O_RDWR) != O_RDWR)
error("%s: not open for read/write", tty);
}
/* Replace current standard output/error fd's with new ones */
debug("duping\n");
if (dup2(STDIN_FILENO, STDOUT_FILENO) == -1 ||
dup2(STDIN_FILENO, STDERR_FILENO) == -1)
error("%s: dup problem: %m", tty); /* we have a problem */
/*
* The following ioctl will fail if stdin is not a tty, but also when
* there is noise on the modem control lines. In the latter case, the
* common course of action is (1) fix your cables (2) give the modem more
* time to properly reset after hanging up. SunOS users can achieve (2)
* by patching the SunOS kernel variable "zsadtrlow" to a larger value;
* 5 seconds seems to be a good value.
*/
if (ioctl(0, TCGETA, tp) < 0)
error("%s: ioctl: %m", tty);
/*
* It seems to be a terminal. Set proper protections and ownership. Mode
* 0622 is suitable for SYSV <4 because /bin/login does not change
* protections. SunOS 4 login will change the protections to 0620 (write
* access for group tty) after the login has succeeded.
*/
#ifdef DEBIAN
{
/* tty to root.dialout 660 */
struct group *gr;
int id;
id = (gr = getgrnam("dialout")) ? gr->gr_gid : 0;
chown(tty, 0, id);
chmod(tty, 0660);
/* vcs,vcsa to root.sys 600 */
if (!strncmp(tty, "tty", 3) && isdigit(tty[3])) {
char *vcs, *vcsa;
if (!(vcs = strdup(tty)))
error("Can't malloc for vcs");
if (!(vcsa = malloc(strlen(tty) + 2)))
error("Can't malloc for vcsa");
strcpy(vcs, "vcs");
strcpy(vcs + 3, tty + 3);
strcpy(vcsa, "vcsa");
strcpy(vcsa + 4, tty + 3);
id = (gr = getgrnam("sys")) ? gr->gr_gid : 0;
chown(vcs, 0, id);
chmod(vcs, 0600);
chown(vcsa, 0, id);
chmod(vcs, 0600);
free(vcs);
free(vcsa);
}
}
#else
(void) chown(tty, 0, 0); /* root, sys */
(void) chmod(tty, 0622); /* crw--w--w- */
#endif
if(chdir_to_root && chdir("/"))
error("chdir to / failed: %m");
}
/* termio_init - initialize termio settings */
static void termio_init(struct termio *tp, int speed, struct options *op)
{
/*
* Initial termio settings: 8-bit characters, raw-mode, blocking i/o.
* Special characters are set after we have read the login name; all
* reads will be done in raw mode anyway. Errors will be dealt with
* lateron.
*/
#ifdef __linux__
/* flush input and output queues, important for modems! */
(void) ioctl(0, TCFLSH, TCIOFLUSH);
#endif
tp->c_cflag = CS8 | HUPCL | CREAD | speed;
if (op->flags & F_LOCAL) {
tp->c_cflag |= CLOCAL;
}
tp->c_iflag = tp->c_lflag = tp->c_oflag = tp->c_line = 0;
tp->c_cc[VMIN] = 1;
tp->c_cc[VTIME] = 0;
/* Optionally enable hardware flow control */
#ifdef CRTSCTS
if (op->flags & F_RTSCTS)
tp->c_cflag |= CRTSCTS;
#endif
(void) ioctl(0, TCSETA, tp);
/* go to blocking input even in local mode */
fcntl(0, F_SETFL, fcntl(0, F_GETFL, 0) & ~O_NONBLOCK);
debug("term_io 2\n");
}
/* auto_baud - extract baud rate from modem status message */
static void auto_baud(struct termio *tp)
{
int speed;
int vmin;
unsigned iflag;
char buf[BUFSIZ];
char *bp;
int nread;
/*
* This works only if the modem produces its status code AFTER raising
* the DCD line, and if the computer is fast enough to set the proper
* baud rate before the message has gone by. We expect a message of the
* following format:
*
* <junk><number><junk>
*
* The number is interpreted as the baud rate of the incoming call. If the
* modem does not tell us the baud rate within one second, we will keep
* using the current baud rate. It is advisable to enable BREAK
* processing (comma-separated list of baud rates) if the processing of
* modem status messages is enabled.
*/
/*
* Use 7-bit characters, don't block if input queue is empty. Errors will
* be dealt with lateron.
*/
iflag = tp->c_iflag;
tp->c_iflag |= ISTRIP; /* enable 8th-bit stripping */
vmin = tp->c_cc[VMIN];
tp->c_cc[VMIN] = 0; /* don't block if queue empty */
(void) ioctl(0, TCSETA, tp);
/*
* Wait for a while, then read everything the modem has said so far and
* try to extract the speed of the dial-in call.
*/
(void) sleep(1);
if ((nread = read(0, buf, sizeof(buf) - 1)) > 0) {
buf[nread] = '\0';
for (bp = buf; bp < buf + nread; bp++) {
if (isascii(*bp) && isdigit(*bp)) {
if ((speed = bcode(bp))) {
tp->c_cflag &= ~CBAUD;
tp->c_cflag |= speed;
}
break;
}
}
}
/* Restore terminal settings. Errors will be dealt with lateron. */
tp->c_iflag = iflag;
tp->c_cc[VMIN] = vmin;
(void) ioctl(0, TCSETA, tp);
}
/* next_speed - select next baud rate */
static void next_speed(struct termio *tp, struct options *op)
{
static int baud_index = FIRST_SPEED; /* current speed index */
baud_index = (baud_index + 1) % op->numspeed;
tp->c_cflag &= ~CBAUD;
tp->c_cflag |= op->speeds[baud_index];
(void) ioctl(0, TCSETA, tp);
}
/* do_prompt - show login prompt, optionally preceded by /etc/issue contents */
static void do_prompt(struct options *op, struct termio *tp)
{
#ifdef ISSUE /* optional: show /etc/issue */
print_login_issue(op->issue, op->tty);
#endif
print_login_prompt();
}
/* caps_lock - string contains upper case without lower case */
/* returns 1 if true, 0 if false */
static int caps_lock(const char *s)
{
int capslock;
for (capslock = 0; *s; s++) {
if (islower(*s))
return (0);
if (capslock == 0)
capslock = isupper(*s);
}
return (capslock);
}
#define logname bb_common_bufsiz1
/* get_logname - get user name, establish parity, speed, erase, kill, eol */
/* return NULL on failure, logname on success */
static char *get_logname(struct options *op, struct chardata *cp, struct termio *tp)
{
char *bp;
char c; /* input character, full eight bits */
char ascval; /* low 7 bits of input character */
int bits; /* # of "1" bits per character */
int mask; /* mask with 1 bit up */
static char *erase[] = { /* backspace-space-backspace */
"\010\040\010", /* space parity */
"\010\040\010", /* odd parity */
"\210\240\210", /* even parity */
"\210\240\210", /* no parity */
};
/* Initialize kill, erase, parity etc. (also after switching speeds). */
*cp = init_chardata;
/* Flush pending input (esp. after parsing or switching the baud rate). */
(void) sleep(1);
(void) ioctl(0, TCFLSH, TCIFLUSH);
/* Prompt for and read a login name. */
for (*logname = 0; *logname == 0; /* void */ ) {
/* Write issue file and prompt, with "parity" bit == 0. */
do_prompt(op, tp);
/* Read name, watch for break, parity, erase, kill, end-of-line. */
for (bp = logname, cp->eol = 0; cp->eol == 0; /* void */ ) {
/* Do not report trivial EINTR/EIO errors. */
if (read(0, &c, 1) < 1) {
if (errno == EINTR || errno == EIO)
exit(0);
error("%s: read: %m", op->tty);
}
/* Do BREAK handling elsewhere. */
if ((c == 0) && op->numspeed > 1)
/* return (0); */
return NULL;
/* Do parity bit handling. */
if (c != (ascval = (c & 0177))) { /* "parity" bit on ? */
for (bits = 1, mask = 1; mask & 0177; mask <<= 1)
if (mask & ascval)
bits++; /* count "1" bits */
cp->parity |= ((bits & 1) ? 1 : 2);
}
/* Do erase, kill and end-of-line processing. */
switch (ascval) {
case CR:
case NL:
*bp = 0; /* terminate logname */
cp->eol = ascval; /* set end-of-line char */
break;
case BS:
case DEL:
case '#':
cp->erase = ascval; /* set erase character */
if (bp > logname) {
(void) write(1, erase[cp->parity], 3);
bp--;
}
break;
case CTL('U'):
case '@':
cp->kill = ascval; /* set kill character */
while (bp > logname) {
(void) write(1, erase[cp->parity], 3);
bp--;
}
break;
case CTL('D'):
exit(0);
default:
if (!isascii(ascval) || !isprint(ascval)) {
/* ignore garbage characters */ ;
} else if (bp - logname >= sizeof(logname) - 1) {
error("%s: input overrun", op->tty);
} else {
(void) write(1, &c, 1); /* echo the character */
*bp++ = ascval; /* and store it */
}
break;
}
}
}
/* Handle names with upper case and no lower case. */
if ((cp->capslock = caps_lock(logname))) {
for (bp = logname; *bp; bp++)
if (isupper(*bp))
*bp = tolower(*bp); /* map name to lower case */
}
return (logname);
}
/* termio_final - set the final tty mode bits */
static void termio_final(struct options *op, struct termio *tp, struct chardata *cp)
{
/* General terminal-independent stuff. */
tp->c_iflag |= IXON | IXOFF; /* 2-way flow control */
tp->c_lflag |= ICANON | ISIG | ECHO | ECHOE | ECHOK | ECHOKE;
/* no longer| ECHOCTL | ECHOPRT */
tp->c_oflag |= OPOST;
/* tp->c_cflag = 0; */
tp->c_cc[VINTR] = DEF_INTR; /* default interrupt */
tp->c_cc[VQUIT] = DEF_QUIT; /* default quit */
tp->c_cc[VEOF] = DEF_EOF; /* default EOF character */
tp->c_cc[VEOL] = DEF_EOL;
tp->c_cc[VSWTC] = DEF_SWITCH; /* default switch character */
/* Account for special characters seen in input. */
if (cp->eol == CR) {
tp->c_iflag |= ICRNL; /* map CR in input to NL */
tp->c_oflag |= ONLCR; /* map NL in output to CR-NL */
}
tp->c_cc[VERASE] = cp->erase; /* set erase character */
tp->c_cc[VKILL] = cp->kill; /* set kill character */
/* Account for the presence or absence of parity bits in input. */
switch (cp->parity) {
case 0: /* space (always 0) parity */
break;
case 1: /* odd parity */
tp->c_cflag |= PARODD;
/* FALLTHROUGH */
case 2: /* even parity */
tp->c_cflag |= PARENB;
tp->c_iflag |= INPCK | ISTRIP;
/* FALLTHROUGH */
case (1 | 2): /* no parity bit */
tp->c_cflag &= ~CSIZE;
tp->c_cflag |= CS7;
break;
}
/* Account for upper case without lower case. */
if (cp->capslock) {
tp->c_iflag |= IUCLC;
tp->c_lflag |= XCASE;
tp->c_oflag |= OLCUC;
}
/* Optionally enable hardware flow control */
#ifdef CRTSCTS
if (op->flags & F_RTSCTS)
tp->c_cflag |= CRTSCTS;
#endif
/* Finally, make the new settings effective */
if (ioctl(0, TCSETA, tp) < 0)
error("%s: ioctl: TCSETA: %m", op->tty);
}
#ifdef SYSV_STYLE
#ifdef CONFIG_FEATURE_UTMP
/* update_utmp - update our utmp entry */
static void update_utmp(char *line)
{
struct utmp ut;
struct utmp *utp;
time_t t;
int mypid = getpid();
#if ! (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1))
struct flock lock;
#endif
/*
* The utmp file holds miscellaneous information about things started by
* /sbin/init and other system-related events. Our purpose is to update
* the utmp entry for the current process, in particular the process type
* and the tty line we are listening to. Return successfully only if the
* utmp file can be opened for update, and if we are able to find our
* entry in the utmp file.
*/
if (access(_PATH_UTMP, R_OK|W_OK) == -1) {
close(creat(_PATH_UTMP, 0664));
}
utmpname(_PATH_UTMP);
setutent();
while ((utp = getutent())
&& !(utp->ut_type == INIT_PROCESS && utp->ut_pid == mypid)) /* nothing */
;
if (utp) {
memcpy(&ut, utp, sizeof(ut));
} else {
/* some inits don't initialize utmp... */
memset(&ut, 0, sizeof(ut));
safe_strncpy(ut.ut_id, line + 3, sizeof(ut.ut_id));
}
/*endutent(); */
strcpy(ut.ut_user, "LOGIN");
safe_strncpy(ut.ut_line, line, sizeof(ut.ut_line));
if (fakehost)
safe_strncpy(ut.ut_host, fakehost, sizeof(ut.ut_host));
time(&t);
ut.ut_time = t;
ut.ut_type = LOGIN_PROCESS;
ut.ut_pid = mypid;
pututline(&ut);
endutent();
#ifdef CONFIG_FEATURE_WTMP
if (access(bb_path_wtmp_file, R_OK|W_OK) == -1)
close(creat(bb_path_wtmp_file, 0664));
updwtmp(bb_path_wtmp_file, &ut);
#endif
}
#endif /* CONFIG_FEATURE_UTMP */
#endif /* SYSV_STYLE */
#undef logname
int getty_main(int argc, char **argv)
{
char *logname = NULL; /* login name, given to /bin/login */
struct chardata chardata; /* set by get_logname() */
struct termio termio; /* terminal mode bits */
static struct options options = {
0, /* show /etc/issue (SYSV_STYLE) */
0, /* no timeout */
_PATH_LOGIN, /* default login program */
"tty1", /* default tty line */
"", /* modem init string */
#ifdef ISSUE
ISSUE, /* default issue file */
#else
NULL,
#endif
0, /* no baud rates known yet */
};
#ifdef DEBUGGING
dbf = bb_xfopen(DEBUGTERM, "w");
{
int i;
for (i = 1; i < argc; i++) {
debug(argv[i]);
debug("\n");
}
}
#endif
/* Parse command-line arguments. */
parse_args(argc, argv, &options);
#ifdef __linux__
setsid();
#endif
/* Update the utmp file. */
#ifdef SYSV_STYLE
#ifdef CONFIG_FEATURE_UTMP
update_utmp(options.tty);
#endif
#endif
debug("calling open_tty\n");
/* Open the tty as standard { input, output, error }. */
open_tty(options.tty, &termio, options.flags & F_LOCAL);
#ifdef __linux__
{
int iv;
iv = getpid();
ioctl(0, TIOCSPGRP, &iv);
}
#endif
/* Initialize the termio settings (raw mode, eight-bit, blocking i/o). */
debug("calling termio_init\n");
termio_init(&termio, options.speeds[FIRST_SPEED], &options);
/* write the modem init string and DON'T flush the buffers */
if (options.flags & F_INITSTRING) {
debug("writing init string\n");
write(1, options.initstring, strlen(options.initstring));
}
if (!(options.flags & F_LOCAL)) {
/* go to blocking write mode unless -L is specified */
fcntl(1, F_SETFL, fcntl(1, F_GETFL, 0) & ~O_NONBLOCK);
}
/* Optionally detect the baud rate from the modem status message. */
debug("before autobaud\n");
if (options.flags & F_PARSE)
auto_baud(&termio);
/* Set the optional timer. */
if (options.timeout)
(void) alarm((unsigned) options.timeout);
/* optionally wait for CR or LF before writing /etc/issue */
if (options.flags & F_WAITCRLF) {
char ch;
debug("waiting for cr-lf\n");
while (read(0, &ch, 1) == 1) {
ch &= 0x7f; /* strip "parity bit" */
#ifdef DEBUGGING
fprintf(dbf, "read %c\n", ch);
#endif
if (ch == '\n' || ch == '\r')
break;
}
}
chardata = init_chardata;
if (!(options.flags & F_NOPROMPT)) {
/* Read the login name. */
debug("reading login name\n");
/* while ((logname = get_logname(&options, &chardata, &termio)) == 0) */
while ((logname = get_logname(&options, &chardata, &termio)) ==
NULL) next_speed(&termio, &options);
}
/* Disable timer. */
if (options.timeout)
(void) alarm(0);
/* Finalize the termio settings. */
termio_final(&options, &termio, &chardata);
/* Now the newline character should be properly written. */
(void) write(1, "\n", 1);
/* Let the login program take care of password validation. */
(void) execl(options.login, options.login, "--", logname, (char *) 0);
error("%s: can't exec %s: %m", options.tty, options.login);
}
Reference in New Issue View Git Blame Copy Permalink