| /* vi: set sw=4 ts=4: */ |
| /* |
| * Based on agetty - 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. |
| * |
| * option added by Eric Rasmussen <ear@usfirst.org> - 12/28/95 |
| * |
| * 1999-02-22 Arkadiusz Mickiewicz <misiek@misiek.eu.org> |
| * - Added Native Language Support |
| * |
| * 1999-05-05 Thorsten Kranzkowski <dl8bcu@gmx.net> |
| * - Enabled hardware flow control before displaying /etc/issue |
| * |
| * 2011-01 Venys Vlasenko |
| * - Removed parity detection code. It can't work reliably: |
| * if all chars received have bit 7 cleared and odd (or even) parity, |
| * it is impossible to determine whether other side is 8-bit,no-parity |
| * or 7-bit,odd(even)-parity. It also interferes with non-ASCII usernames. |
| * - From now on, we assume that parity is correctly set. |
| * |
| * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| */ |
| |
| #include "libbb.h" |
| #include <syslog.h> |
| #ifndef IUCLC |
| # define IUCLC 0 |
| #endif |
| |
| #ifndef LOGIN_PROCESS |
| # undef ENABLE_FEATURE_UTMP |
| # undef ENABLE_FEATURE_WTMP |
| # define ENABLE_FEATURE_UTMP 0 |
| # define ENABLE_FEATURE_WTMP 0 |
| #endif |
| |
| |
| /* The following is used for understandable diagnostics */ |
| #ifdef DEBUGGING |
| static FILE *dbf; |
| # define DEBUGTERM "/dev/ttyp0" |
| # define debug(...) do { fprintf(dbf, __VA_ARGS__); fflush(dbf); } while (0) |
| #else |
| # define debug(...) ((void)0) |
| #endif |
| |
| |
| /* |
| * 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. |
| */ |
| #undef _PATH_LOGIN |
| #define _PATH_LOGIN "/bin/login" |
| |
| /* Displayed before the login prompt. |
| * If ISSUE is not defined, getty 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" |
| |
| /* Macro to build Ctrl-LETTER. Assumes ASCII dialect */ |
| #define CTL(x) ((x) ^ 0100) |
| |
| /* |
| * When multiple baud rates are specified on the command line, |
| * the first one we will try is the first one specified. |
| */ |
| #define MAX_SPEED 10 /* max. nr. of baud rates */ |
| |
| struct globals { |
| unsigned timeout; |
| const char *login; /* login program */ |
| const char *fakehost; |
| const char *tty_name; |
| char *initstring; /* modem init string */ |
| const char *issue; /* alternative issue file */ |
| int numspeed; /* number of baud rates to try */ |
| int speeds[MAX_SPEED]; /* baud rates to be tried */ |
| unsigned char eol; /* end-of-line char seen (CR or NL) */ |
| struct termios tty_attrs; |
| char line_buf[128]; |
| }; |
| |
| #define G (*ptr_to_globals) |
| #define INIT_G() do { \ |
| SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \ |
| } while (0) |
| |
| //usage:#define getty_trivial_usage |
| //usage: "[OPTIONS] BAUD_RATE[,BAUD_RATE]... TTY [TERMTYPE]" |
| //usage:#define getty_full_usage "\n\n" |
| //usage: "Open TTY, prompt for login name, then invoke /bin/login\n" |
| //usage: "\n -h Enable hardware RTS/CTS flow control" |
| //usage: "\n -L Set CLOCAL (ignore Carrier Detect state)" |
| //usage: "\n -m Get baud rate from modem's CONNECT status message" |
| //usage: "\n -n Don't prompt for login name" |
| //usage: "\n -w Wait for CR or LF before sending /etc/issue" |
| //usage: "\n -i Don't display /etc/issue" |
| //usage: "\n -f ISSUE_FILE Display ISSUE_FILE instead of /etc/issue" |
| //usage: "\n -l LOGIN Invoke LOGIN instead of /bin/login" |
| //usage: "\n -t SEC Terminate after SEC if no login name is read" |
| //usage: "\n -I INITSTR Send INITSTR before anything else" |
| //usage: "\n -H HOST Log HOST into the utmp file as the hostname" |
| //usage: "\n" |
| //usage: "\nBAUD_RATE of 0 leaves it unchanged" |
| |
| static const char opt_string[] ALIGN1 = "I:LH:f:hil:mt:wn"; |
| #define F_INITSTRING (1 << 0) /* -I */ |
| #define F_LOCAL (1 << 1) /* -L */ |
| #define F_FAKEHOST (1 << 2) /* -H */ |
| #define F_CUSTISSUE (1 << 3) /* -f */ |
| #define F_RTSCTS (1 << 4) /* -h */ |
| #define F_NOISSUE (1 << 5) /* -i */ |
| #define F_LOGIN (1 << 6) /* -l */ |
| #define F_PARSE (1 << 7) /* -m */ |
| #define F_TIMEOUT (1 << 8) /* -t */ |
| #define F_WAITCRLF (1 << 9) /* -w */ |
| #define F_NOPROMPT (1 << 10) /* -n */ |
| |
| |
| /* convert speed string to speed code; return <= 0 on failure */ |
| static int bcode(const char *s) |
| { |
| int value = bb_strtou(s, NULL, 10); /* yes, int is intended! */ |
| if (value < 0) /* bad terminating char, overflow, etc */ |
| return value; |
| return tty_value_to_baud(value); |
| } |
| |
| /* parse alternate baud rates */ |
| static void parse_speeds(char *arg) |
| { |
| char *cp; |
| |
| /* NB: at least one iteration is always done */ |
| debug("entered parse_speeds\n"); |
| while ((cp = strsep(&arg, ",")) != NULL) { |
| G.speeds[G.numspeed] = bcode(cp); |
| if (G.speeds[G.numspeed] < 0) |
| bb_error_msg_and_die("bad speed: %s", cp); |
| /* note: arg "0" turns into speed B0 */ |
| G.numspeed++; |
| if (G.numspeed > MAX_SPEED) |
| bb_error_msg_and_die("too many alternate speeds"); |
| } |
| debug("exiting parse_speeds\n"); |
| } |
| |
| /* parse command-line arguments */ |
| static void parse_args(char **argv) |
| { |
| char *ts; |
| int flags; |
| |
| opt_complementary = "-2:t+"; /* at least 2 args; -t N */ |
| flags = getopt32(argv, opt_string, |
| &G.initstring, &G.fakehost, &G.issue, |
| &G.login, &G.timeout |
| ); |
| if (flags & F_INITSTRING) { |
| G.initstring = xstrdup(G.initstring); |
| /* decode \ddd octal codes into chars */ |
| strcpy_and_process_escape_sequences(G.initstring, G.initstring); |
| } |
| argv += optind; |
| debug("after getopt\n"); |
| |
| /* We loosen up a bit and accept both "baudrate tty" and "tty baudrate" */ |
| G.tty_name = argv[0]; |
| ts = argv[1]; /* baud rate(s) */ |
| if (isdigit(argv[0][0])) { |
| /* A number first, assume it's a speed (BSD style) */ |
| G.tty_name = ts; /* tty name is in argv[1] */ |
| ts = argv[0]; /* baud rate(s) */ |
| } |
| parse_speeds(ts); |
| |
| if (argv[2]) |
| xsetenv("TERM", argv[2]); |
| |
| debug("exiting parse_args\n"); |
| } |
| |
| /* set up tty as standard input, output, error */ |
| static void open_tty(void) |
| { |
| /* Set up new standard input, unless we are given an already opened port */ |
| if (NOT_LONE_DASH(G.tty_name)) { |
| if (G.tty_name[0] != '/') |
| G.tty_name = xasprintf("/dev/%s", G.tty_name); /* will leak it */ |
| |
| /* Open the tty as standard input */ |
| debug("open(2)\n"); |
| close(0); |
| xopen(G.tty_name, O_RDWR | O_NONBLOCK); /* uses fd 0 */ |
| |
| /* Set proper protections and ownership */ |
| fchown(0, 0, 0); /* 0:0 */ |
| fchmod(0, 0620); /* crw--w---- */ |
| } else { |
| char *n; |
| /* |
| * Standard input should already be connected to an open port. |
| * Make sure it is open for read/write. |
| */ |
| if ((fcntl(0, F_GETFL) & (O_RDWR|O_RDONLY|O_WRONLY)) != O_RDWR) |
| bb_error_msg_and_die("stdin is not open for read/write"); |
| |
| /* Try to get real tty name instead of "-" */ |
| n = xmalloc_ttyname(0); |
| if (n) |
| G.tty_name = n; |
| } |
| applet_name = xasprintf("getty: %s", skip_dev_pfx(G.tty_name)); |
| } |
| |
| static void set_tty_attrs(void) |
| { |
| if (tcsetattr_stdin_TCSANOW(&G.tty_attrs) < 0) |
| bb_perror_msg_and_die("tcsetattr"); |
| } |
| |
| /* We manipulate tty_attrs this way: |
| * - first, we read existing tty_attrs |
| * - init_tty_attrs modifies some parts and sets it |
| * - auto_baud and/or BREAK processing can set different speed and set tty attrs |
| * - finalize_tty_attrs again modifies some parts and sets tty attrs before |
| * execing login |
| */ |
| static void init_tty_attrs(int speed) |
| { |
| /* Try to drain output buffer, with 5 sec timeout. |
| * Added on request from users of ~600 baud serial interface |
| * with biggish buffer on a 90MHz CPU. |
| * They were losing hundreds of bytes of buffered output |
| * on tcflush. |
| */ |
| signal_no_SA_RESTART_empty_mask(SIGALRM, record_signo); |
| alarm(5); |
| tcdrain(STDIN_FILENO); |
| alarm(0); |
| |
| /* Flush input and output queues, important for modems! */ |
| tcflush(STDIN_FILENO, TCIOFLUSH); |
| |
| /* Set speed if it wasn't specified as "0" on command line */ |
| if (speed != B0) |
| cfsetspeed(&G.tty_attrs, speed); |
| |
| /* Initial 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. |
| */ |
| /* Clear all bits except: */ |
| G.tty_attrs.c_cflag &= (0 |
| /* 2 stop bits (1 otherwise) |
| * Enable parity bit (both on input and output) |
| * Odd parity (else even) |
| */ |
| | CSTOPB | PARENB | PARODD |
| #ifdef CMSPAR |
| | CMSPAR /* mark or space parity */ |
| #endif |
| #ifdef CBAUD |
| | CBAUD /* (output) baud rate */ |
| #endif |
| #ifdef CBAUDEX |
| | CBAUDEX /* (output) baud rate */ |
| #endif |
| #ifdef CIBAUD |
| | CIBAUD /* input baud rate */ |
| #endif |
| ); |
| /* Set: 8 bits; hang up (drop DTR) on last close; enable receive */ |
| G.tty_attrs.c_cflag |= CS8 | HUPCL | CREAD; |
| if (option_mask32 & F_LOCAL) { |
| /* ignore Carrier Detect pin: |
| * opens don't block when CD is low, |
| * losing CD doesn't hang up processes whose ctty is this tty |
| */ |
| G.tty_attrs.c_cflag |= CLOCAL; |
| } |
| #ifdef CRTSCTS |
| if (option_mask32 & F_RTSCTS) |
| G.tty_attrs.c_cflag |= CRTSCTS; /* flow control using RTS/CTS pins */ |
| #endif |
| G.tty_attrs.c_iflag = 0; |
| G.tty_attrs.c_lflag = 0; |
| /* non-raw output; add CR to each NL */ |
| G.tty_attrs.c_oflag = OPOST | ONLCR; |
| |
| /* reads would block only if < 1 char is available */ |
| G.tty_attrs.c_cc[VMIN] = 1; |
| /* no timeout (reads block forever) */ |
| G.tty_attrs.c_cc[VTIME] = 0; |
| #ifdef __linux__ |
| G.tty_attrs.c_line = 0; |
| #endif |
| |
| set_tty_attrs(); |
| |
| debug("term_io 2\n"); |
| } |
| |
| static void finalize_tty_attrs(void) |
| { |
| /* software flow control on output (stop sending if XOFF is recvd); |
| * and on input (send XOFF when buffer is full) |
| */ |
| G.tty_attrs.c_iflag |= IXON | IXOFF; |
| if (G.eol == '\r') { |
| G.tty_attrs.c_iflag |= ICRNL; /* map CR on input to NL */ |
| } |
| /* Other bits in c_iflag: |
| * IXANY Any recvd char enables output (any char is also a XON) |
| * INPCK Enable parity check |
| * IGNPAR Ignore parity errors (drop bad bytes) |
| * PARMRK Mark parity errors with 0xff, 0x00 prefix |
| * (else bad byte is received as 0x00) |
| * ISTRIP Strip parity bit |
| * IGNBRK Ignore break condition |
| * BRKINT Send SIGINT on break - maybe set this? |
| * INLCR Map NL to CR |
| * IGNCR Ignore CR |
| * ICRNL Map CR to NL |
| * IUCLC Map uppercase to lowercase |
| * IMAXBEL Echo BEL on input line too long |
| * IUTF8 Appears to affect tty's idea of char widths, |
| * observed to improve backspacing through Unicode chars |
| */ |
| |
| /* line buffered input (NL or EOL or EOF chars end a line); |
| * recognize INT/QUIT/SUSP chars; |
| * echo input chars; |
| * echo BS-SP-BS on erase character; |
| * echo kill char specially, not as ^c (ECHOKE controls how exactly); |
| * erase all input via BS-SP-BS on kill char (else go to next line) |
| */ |
| G.tty_attrs.c_lflag |= ICANON | ISIG | ECHO | ECHOE | ECHOK | ECHOKE; |
| /* Other bits in c_lflag: |
| * XCASE Map uppercase to \lowercase [tried, doesn't work] |
| * ECHONL Echo NL even if ECHO is not set |
| * ECHOCTL Echo ctrl chars as ^c (else don't echo) - maybe set this? |
| * ECHOPRT On erase, echo erased chars |
| * [qwe<BS><BS><BS> input looks like "qwe\ewq/" on screen] |
| * NOFLSH Don't flush input buffer after interrupt or quit chars |
| * IEXTEN Enable extended functions (??) |
| * [glibc says it enables c_cc[LNEXT] "enter literal char" |
| * and c_cc[VDISCARD] "toggle discard buffered output" chars] |
| * FLUSHO Output being flushed (c_cc[VDISCARD] is in effect) |
| * PENDIN Retype pending input at next read or input char |
| * (c_cc[VREPRINT] is being processed) |
| * TOSTOP Send SIGTTOU for background output |
| * (why "stty sane" unsets this bit?) |
| */ |
| |
| G.tty_attrs.c_cc[VINTR] = CTL('C'); |
| G.tty_attrs.c_cc[VQUIT] = CTL('\\'); |
| G.tty_attrs.c_cc[VEOF] = CTL('D'); |
| G.tty_attrs.c_cc[VEOL] = '\n'; |
| #ifdef VSWTC |
| G.tty_attrs.c_cc[VSWTC] = 0; |
| #endif |
| #ifdef VSWTCH |
| G.tty_attrs.c_cc[VSWTCH] = 0; |
| #endif |
| G.tty_attrs.c_cc[VKILL] = CTL('U'); |
| /* Other control chars: |
| * VEOL2 |
| * VERASE, VWERASE - (word) erase. we may set VERASE in get_logname |
| * VREPRINT - reprint current input buffer |
| * VLNEXT, VDISCARD, VSTATUS |
| * VSUSP, VDSUSP - send (delayed) SIGTSTP |
| * VSTART, VSTOP - chars used for IXON/IXOFF |
| */ |
| |
| set_tty_attrs(); |
| |
| /* Now the newline character should be properly written */ |
| full_write(STDOUT_FILENO, "\n", 1); |
| } |
| |
| /* extract baud rate from modem status message */ |
| static void auto_baud(void) |
| { |
| 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. |
| */ |
| |
| G.tty_attrs.c_cc[VMIN] = 0; /* don't block reads (min read is 0 chars) */ |
| set_tty_attrs(); |
| |
| /* |
| * Wait for a while, then read everything the modem has said so far and |
| * try to extract the speed of the dial-in call. |
| */ |
| sleep(1); |
| nread = safe_read(STDIN_FILENO, G.line_buf, sizeof(G.line_buf) - 1); |
| if (nread > 0) { |
| int speed; |
| char *bp; |
| G.line_buf[nread] = '\0'; |
| for (bp = G.line_buf; bp < G.line_buf + nread; bp++) { |
| if (isdigit(*bp)) { |
| speed = bcode(bp); |
| if (speed > 0) |
| cfsetspeed(&G.tty_attrs, speed); |
| break; |
| } |
| } |
| } |
| |
| /* Restore terminal settings */ |
| G.tty_attrs.c_cc[VMIN] = 1; /* restore to value set by init_tty_attrs */ |
| set_tty_attrs(); |
| } |
| |
| /* get user name, establish parity, speed, erase, kill, eol; |
| * return NULL on BREAK, logname on success |
| */ |
| static char *get_logname(void) |
| { |
| char *bp; |
| char c; |
| |
| /* Flush pending input (esp. after parsing or switching the baud rate) */ |
| usleep(100*1000); /* 0.1 sec */ |
| tcflush(STDIN_FILENO, TCIFLUSH); |
| |
| /* Prompt for and read a login name */ |
| do { |
| /* Write issue file and prompt */ |
| #ifdef ISSUE |
| if (!(option_mask32 & F_NOISSUE)) |
| print_login_issue(G.issue, G.tty_name); |
| #endif |
| print_login_prompt(); |
| |
| /* Read name, watch for break, erase, kill, end-of-line */ |
| bp = G.line_buf; |
| while (1) { |
| /* Do not report trivial EINTR/EIO errors */ |
| errno = EINTR; /* make read of 0 bytes be silent too */ |
| if (read(STDIN_FILENO, &c, 1) < 1) { |
| finalize_tty_attrs(); |
| if (errno == EINTR || errno == EIO) |
| exit(EXIT_SUCCESS); |
| bb_perror_msg_and_die(bb_msg_read_error); |
| } |
| |
| switch (c) { |
| case '\r': |
| case '\n': |
| *bp = '\0'; |
| G.eol = c; |
| goto got_logname; |
| case CTL('H'): |
| case 0x7f: |
| G.tty_attrs.c_cc[VERASE] = c; |
| if (bp > G.line_buf) { |
| full_write(STDOUT_FILENO, "\010 \010", 3); |
| bp--; |
| } |
| break; |
| case CTL('U'): |
| while (bp > G.line_buf) { |
| full_write(STDOUT_FILENO, "\010 \010", 3); |
| bp--; |
| } |
| break; |
| case CTL('C'): |
| case CTL('D'): |
| finalize_tty_attrs(); |
| exit(EXIT_SUCCESS); |
| case '\0': |
| /* BREAK. If we have speeds to try, |
| * return NULL (will switch speeds and return here) */ |
| if (G.numspeed > 1) |
| return NULL; |
| /* fall through and ignore it */ |
| default: |
| if ((unsigned char)c < ' ') { |
| /* ignore garbage characters */ |
| } else if ((int)(bp - G.line_buf) < sizeof(G.line_buf) - 1) { |
| /* echo and store the character */ |
| full_write(STDOUT_FILENO, &c, 1); |
| *bp++ = c; |
| } |
| break; |
| } |
| } /* end of get char loop */ |
| got_logname: ; |
| } while (G.line_buf[0] == '\0'); /* while logname is empty */ |
| |
| return G.line_buf; |
| } |
| |
| static void alarm_handler(int sig UNUSED_PARAM) |
| { |
| finalize_tty_attrs(); |
| _exit(EXIT_SUCCESS); |
| } |
| |
| int getty_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int getty_main(int argc UNUSED_PARAM, char **argv) |
| { |
| int n; |
| pid_t pid, tsid; |
| char *logname; |
| |
| INIT_G(); |
| G.login = _PATH_LOGIN; /* default login program */ |
| #ifdef ISSUE |
| G.issue = ISSUE; /* default issue file */ |
| #endif |
| G.eol = '\r'; |
| |
| /* Parse command-line arguments */ |
| parse_args(argv); |
| |
| /* Create new session and pgrp, lose controlling tty */ |
| pid = setsid(); /* this also gives us our pid :) */ |
| if (pid < 0) { |
| int fd; |
| /* :( |
| * docs/ctty.htm says: |
| * "This is allowed only when the current process |
| * is not a process group leader". |
| * Thus, setsid() will fail if we _already_ are |
| * a session leader - which is quite possible for getty! |
| */ |
| pid = getpid(); |
| if (getsid(0) != pid) |
| bb_perror_msg_and_die("setsid"); |
| /* Looks like we are already a session leader. |
| * In this case (setsid failed) we may still have ctty, |
| * and it may be different from tty we need to control! |
| * If we still have ctty, on Linux ioctl(TIOCSCTTY) |
| * (which we are going to use a bit later) always fails - |
| * even if we try to take ctty which is already ours! |
| * Try to drop old ctty now to prevent that. |
| * Use O_NONBLOCK: old ctty may be a serial line. |
| */ |
| fd = open("/dev/tty", O_RDWR | O_NONBLOCK); |
| if (fd >= 0) { |
| /* TIOCNOTTY sends SIGHUP to the foreground |
| * process group - which may include us! |
| * Make sure to not die on it: |
| */ |
| sighandler_t old = signal(SIGHUP, SIG_IGN); |
| ioctl(fd, TIOCNOTTY); |
| close(fd); |
| signal(SIGHUP, old); |
| } |
| } |
| |
| /* Close stdio, and stray descriptors, just in case */ |
| n = xopen(bb_dev_null, O_RDWR); |
| /* dup2(n, 0); - no, we need to handle "getty - 9600" too */ |
| xdup2(n, 1); |
| xdup2(n, 2); |
| while (n > 2) |
| close(n--); |
| |
| /* Logging. We want special flavor of error_msg_and_die */ |
| die_sleep = 10; |
| msg_eol = "\r\n"; |
| /* most likely will internally use fd #3 in CLOEXEC mode: */ |
| openlog(applet_name, LOG_PID, LOG_AUTH); |
| logmode = LOGMODE_BOTH; |
| |
| #ifdef DEBUGGING |
| dbf = xfopen_for_write(DEBUGTERM); |
| for (n = 1; argv[n]; n++) { |
| debug(argv[n]); |
| debug("\n"); |
| } |
| #endif |
| |
| /* Open the tty as standard input, if it is not "-" */ |
| debug("calling open_tty\n"); |
| open_tty(); |
| ndelay_off(STDIN_FILENO); |
| debug("duping\n"); |
| xdup2(STDIN_FILENO, 1); |
| xdup2(STDIN_FILENO, 2); |
| |
| /* Steal ctty if we don't have it yet */ |
| tsid = tcgetsid(STDIN_FILENO); |
| if (tsid < 0 || pid != tsid) { |
| if (ioctl(STDIN_FILENO, TIOCSCTTY, /*force:*/ (long)1) < 0) |
| bb_perror_msg_and_die("TIOCSCTTY"); |
| } |
| |
| #ifdef __linux__ |
| /* Make ourself a foreground process group within our session */ |
| if (tcsetpgrp(STDIN_FILENO, pid) < 0) |
| bb_perror_msg_and_die("tcsetpgrp"); |
| #endif |
| |
| /* |
| * 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 (tcgetattr(STDIN_FILENO, &G.tty_attrs) < 0) |
| bb_perror_msg_and_die("tcgetattr"); |
| |
| /* Update the utmp file. This tty is ours now! */ |
| update_utmp(pid, LOGIN_PROCESS, G.tty_name, "LOGIN", G.fakehost); |
| |
| /* Initialize tty attrs (raw mode, eight-bit, blocking i/o) */ |
| debug("calling init_tty_attrs\n"); |
| init_tty_attrs(G.speeds[0]); |
| |
| /* Write the modem init string and DON'T flush the buffers */ |
| if (option_mask32 & F_INITSTRING) { |
| debug("writing init string\n"); |
| full_write1_str(G.initstring); |
| } |
| |
| /* Optionally detect the baud rate from the modem status message */ |
| debug("before autobaud\n"); |
| if (option_mask32 & F_PARSE) |
| auto_baud(); |
| |
| /* Set the optional timer */ |
| signal(SIGALRM, alarm_handler); |
| alarm(G.timeout); /* if 0, alarm is not set */ |
| |
| /* Optionally wait for CR or LF before writing /etc/issue */ |
| if (option_mask32 & F_WAITCRLF) { |
| char ch; |
| debug("waiting for cr-lf\n"); |
| while (safe_read(STDIN_FILENO, &ch, 1) == 1) { |
| debug("read %x\n", (unsigned char)ch); |
| if (ch == '\n' || ch == '\r') |
| break; |
| } |
| } |
| |
| logname = NULL; |
| if (!(option_mask32 & F_NOPROMPT)) { |
| /* NB: init_tty_attrs already set line speed |
| * to G.speeds[0] */ |
| int baud_index = 0; |
| |
| while (1) { |
| /* Read the login name */ |
| debug("reading login name\n"); |
| logname = get_logname(); |
| if (logname) |
| break; |
| /* We are here only if G.numspeed > 1 */ |
| baud_index = (baud_index + 1) % G.numspeed; |
| cfsetspeed(&G.tty_attrs, G.speeds[baud_index]); |
| set_tty_attrs(); |
| } |
| } |
| |
| /* Disable timer */ |
| alarm(0); |
| |
| finalize_tty_attrs(); |
| |
| /* Let the login program take care of password validation */ |
| /* We use PATH because we trust that root doesn't set "bad" PATH, |
| * and getty is not suid-root applet */ |
| /* With -n, logname == NULL, and login will ask for username instead */ |
| BB_EXECLP(G.login, G.login, "--", logname, NULL); |
| bb_error_msg_and_die("can't execute '%s'", G.login); |
| } |