/* vi: set sw=4 ts=4: */
-/* agetty.c - another getty program for Linux. By W. Z. Venema 1989
+/*
+ * 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. The entire man-page used to
- * be here. Now read the real man-page agetty.8 instead.
+ * 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
+ * - Added Native Language Support
*
* 1999-05-05 Thorsten Kranzkowski <dl8bcu@gmx.net>
- * - enable hardware flow control before displaying /etc/issue
+ * - 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 tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
+//config:config GETTY
+//config: bool "getty (10 kb)"
+//config: default y
+//config: select FEATURE_SYSLOG
+//config: help
+//config: getty lets you log in on a tty. It is normally invoked by init.
+//config:
+//config: Note that you can save a few bytes by disabling it and
+//config: using login applet directly.
+//config: If you need to reset tty attributes before calling login,
+//config: this script approximates getty:
+//config:
+//config: exec </dev/$1 >/dev/$1 2>&1 || exit 1
+//config: reset
+//config: stty sane; stty ispeed 38400; stty ospeed 38400
+//config: printf "%s login: " "`hostname`"
+//config: read -r login
+//config: exec /bin/login "$login"
+
+//applet:IF_GETTY(APPLET(getty, BB_DIR_SBIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_GETTY) += getty.o
#include "libbb.h"
#include <syslog.h>
+#ifndef IUCLC
+# define IUCLC 0
+#endif
-#if ENABLE_FEATURE_UTMP
-# include <utmp.h> /* LOGIN_PROCESS */
+#ifndef LOGIN_PROCESS
+# undef ENABLE_FEATURE_UTMP
+# undef ENABLE_FEATURE_WTMP
+# define ENABLE_FEATURE_UTMP 0
+# define ENABLE_FEATURE_WTMP 0
#endif
-#ifndef IUCLC
-# define IUCLC 0
+
+/* 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
-/*
- * 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 */
-#include <sys/utsname.h>
-#else /* if !sysV style, wtmp/utmp code is off */
-#undef ENABLE_FEATURE_UTMP
-#undef ENABLE_FEATURE_WTMP
-#define ENABLE_FEATURE_UTMP 0
-#define ENABLE_FEATURE_WTMP 0
-#endif /* LOGIN_PROCESS */
/*
* Things you may want to modify.
* below. Note, however, that DEL cannot be used for interrupt generation
* and for line editing at the same time.
*/
-
-/* I doubt there are systems which still need this */
-#undef HANDLE_ALLCAPS
-#undef ANCIENT_BS_KILL_CHARS
-
+#undef _PATH_LOGIN
#define _PATH_LOGIN "/bin/login"
-/* If ISSUE is not defined, getty will never display the contents of the
+/* 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" /* 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 */
+#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.
+ * 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 */
-/* Storage for command-line options. */
-struct options {
- int flags; /* toggle switches, see below */
- unsigned timeout; /* time-out period */
+struct globals {
+ unsigned timeout;
const char *login; /* login program */
- const char *tty; /* name of tty */
- const char *initstring; /* modem init string */
+ 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];
};
-/* Storage for things detected while the login name was read. */
-struct chardata {
- unsigned char erase; /* erase character */
- unsigned char kill; /* kill character */
- unsigned char eol; /* end-of-line character */
- unsigned char parity; /* what parity did we see */
- /* (parity & 1): saw odd parity char with 7th bit set */
- /* (parity & 2): saw even parity char with 7th bit set */
- /* parity == 0: probably 7-bit, space parity? */
- /* parity == 1: probably 7-bit, odd parity? */
- /* parity == 2: probably 7-bit, even parity? */
- /* parity == 3: definitely 8 bit, no parity! */
- /* Hmm... with any value of "parity" 8 bit, no parity is possible */
-#ifdef HANDLE_ALLCAPS
- unsigned char capslock; /* upper case without lower case */
-#endif
-};
-
-
-/* Initial values for the above. */
-static const struct chardata init_chardata = {
- DEF_ERASE, /* default erase character */
- DEF_KILL, /* default kill character */
- 13, /* default eol char */
- 0, /* space parity */
-#ifdef HANDLE_ALLCAPS
- 0, /* no capslock */
-#endif
-};
-
-static const char opt_string[] ALIGN1 = "I:LH:f:hil:mt:wn";
-#define F_INITSTRING (1 << 0) /* -I initstring is set */
-#define F_LOCAL (1 << 1) /* -L force local */
-#define F_FAKEHOST (1 << 2) /* -H fake hostname */
-#define F_CUSTISSUE (1 << 3) /* -f give alternative issue file */
-#define F_RTSCTS (1 << 4) /* -h enable RTS/CTS flow control */
-#define F_ISSUE (1 << 5) /* -i display /etc/issue */
-#define F_LOGIN (1 << 6) /* -l non-default login program */
-#define F_PARSE (1 << 7) /* -m process modem status messages */
-#define F_TIMEOUT (1 << 8) /* -t time out */
-#define F_WAITCRLF (1 << 9) /* -w wait for CR or LF */
-#define F_NOPROMPT (1 << 10) /* -n don't ask for login name */
-
-
-#define line_buf bb_common_bufsiz1
-
-/* 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
-
-
-/* bcode - convert speed string to speed code; return <= 0 on failure */
+#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"
+
+#define OPT_STR "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! */
return tty_value_to_baud(value);
}
-/* parse_speeds - parse alternate baud rates */
-static void parse_speeds(struct options *op, char *arg)
+/* 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) {
- op->speeds[op->numspeed] = bcode(cp);
- if (op->speeds[op->numspeed] < 0)
+ 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 */
- op->numspeed++;
- if (op->numspeed > MAX_SPEED)
- bb_error_msg_and_die("too many alternate speeds");
+ G.numspeed++;
+ if (G.numspeed > MAX_SPEED)
+ bb_simple_error_msg_and_die("too many alternate speeds");
}
debug("exiting parse_speeds\n");
}
-/* parse_args - parse command-line arguments */
-static void parse_args(char **argv, struct options *op, char **fakehost_p)
+/* parse command-line arguments */
+static void parse_args(char **argv)
{
char *ts;
-
- opt_complementary = "-2:t+"; /* at least 2 args; -t N */
- op->flags = getopt32(argv, opt_string,
- &(op->initstring), fakehost_p, &(op->issue),
- &(op->login), &op->timeout);
- argv += optind;
- if (op->flags & F_INITSTRING) {
- const char *p = op->initstring;
- char *q;
-
- op->initstring = q = xstrdup(p);
- /* 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';
+ int flags;
+
+ flags = getopt32(argv, "^" OPT_STR "\0" "-2"/* at least 2 args*/,
+ &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);
}
- op->flags ^= F_ISSUE; /* invert flag "show /etc/issue" */
+ argv += optind;
debug("after getopt\n");
- /* we loosen up a bit and accept both "baudrate tty" and "tty baudrate" */
- op->tty = argv[0]; /* tty name */
- ts = argv[1]; /* baud rate(s) */
+ /* 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) */
- op->tty = ts; /* tty name is in argv[1] */
- ts = argv[0]; /* baud rate(s) */
+ /* 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(op, ts);
-
-// TODO: if applet_name is set to "getty: TTY", bb_error_msg's get simpler!
-// grep for "%s:"
+ parse_speeds(ts);
if (argv[2])
xsetenv("TERM", argv[2]);
debug("exiting parse_args\n");
}
-/* open_tty - set up tty as standard { input, output, error } */
-static void open_tty(const char *tty)
+/* 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(tty)) {
-// struct stat st;
-// int cur_dir_fd;
-// int fd;
-
- /* Sanity checks... */
-// cur_dir_fd = xopen(".", O_DIRECTORY | O_NONBLOCK);
-// xchdir("/dev");
-// xstat(tty, &st);
-// if (!S_ISCHR(st.st_mode))
-// bb_error_msg_and_die("%s: not a character device", tty);
-
- if (tty[0] != '/')
- tty = xasprintf("/dev/%s", tty); /* will leak it */
-
- /* Open the tty as standard input. */
+ /* 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);
- /*fd =*/ xopen(tty, O_RDWR | O_NONBLOCK); /* uses fd 0 */
+ xopen(G.tty_name, O_RDWR | O_NONBLOCK); /* uses fd 0 */
-// /* Restore current directory */
-// fchdir(cur_dir_fd);
-
- /* Open the tty as standard input, continued */
-// xmove_fd(fd, 0);
-// /* fd is >= cur_dir_fd, and cur_dir_fd gets closed too here: */
-// while (fd > 2)
-// close(fd--);
-
- /* Set proper protections and ownership. */
+ /* 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.
+ * 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_RDWR)
- bb_error_msg_and_die("stdin is not open for read/write");
+ if ((fcntl(0, F_GETFL) & (O_RDWR|O_RDONLY|O_WRONLY)) != O_RDWR)
+ bb_simple_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));
}
-/* termios_init - initialize termios settings */
-static void termios_init(struct termios *tp, int speed, struct options *op)
+static void set_tty_attrs(void)
{
- speed_t ispeed, ospeed;
- /*
- * Initial termios settings: 8-bit characters, raw-mode, blocking i/o.
+ if (tcsetattr_stdin_TCSANOW(&G.tty_attrs) < 0)
+ bb_simple_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. Errors will be dealt with
- * later on.
+ * reads will be done in raw mode anyway.
*/
-#ifdef __linux__
- /* flush input and output queues, important for modems! */
- ioctl(0, TCFLSH, TCIOFLUSH); /* tcflush(0, TCIOFLUSH)? - same */
+ /* 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
- ispeed = ospeed = speed;
- if (speed == B0) {
- /* Speed was specified as "0" on command line.
- * Just leave it unchanged */
- ispeed = cfgetispeed(tp);
- ospeed = cfgetospeed(tp);
+#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;
}
- tp->c_cflag = CS8 | HUPCL | CREAD;
- if (op->flags & F_LOCAL)
- tp->c_cflag |= CLOCAL;
- cfsetispeed(tp, ispeed);
- cfsetospeed(tp, ospeed);
-
- tp->c_iflag = tp->c_lflag = tp->c_line = 0;
- tp->c_oflag = OPOST | ONLCR;
- 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;
+ 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 will 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
- tcsetattr_stdin_TCSANOW(tp);
+ set_tty_attrs();
debug("term_io 2\n");
}
-/* auto_baud - extract baud rate from modem status message */
-static void auto_baud(char *buf, unsigned size_buf, struct termios *tp)
+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
+ */
+
+ /* ICANON line buffered input (NL or EOL or EOF chars end a line);
+ * ISIG recognize INT/QUIT/SUSP chars;
+ * ECHO echo input chars;
+ * ECHOE echo BS-SP-BS on erase character;
+ * ECHOK echo kill char specially, not as ^c (ECHOKE controls how exactly);
+ * ECHOKE erase all input via BS-SP-BS on kill char (else go to next line)
+ * ECHOCTL Echo ctrl chars as ^c (else echo verbatim:
+ * e.g. up arrow emits "ESC-something" and thus moves cursor up!)
+ */
+ G.tty_attrs.c_lflag |= ICANON | ISIG | ECHO | ECHOE | ECHOK | ECHOKE | ECHOCTL;
+ /* Other bits in c_lflag:
+ * XCASE Map uppercase to \lowercase [tried, doesn't work]
+ * ECHONL Echo NL even if ECHO is not set
+ * 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 speed;
- int vmin;
- unsigned iflag;
- char *bp;
int nread;
/*
* modem status messages is enabled.
*/
- /*
- * Use 7-bit characters, don't block if input queue is empty. Errors will
- * be dealt with later on.
- */
- 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 */
- tcsetattr_stdin_TCSANOW(tp);
+ 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, buf, size_buf - 1);
+ nread = safe_read(STDIN_FILENO, G.line_buf, sizeof(G.line_buf) - 1);
if (nread > 0) {
- buf[nread] = '\0';
- for (bp = buf; bp < buf + nread; bp++) {
+ 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) {
- tp->c_cflag &= ~CBAUD;
- tp->c_cflag |= speed;
- }
+ if (speed > 0)
+ cfsetspeed(&G.tty_attrs, speed);
break;
}
}
}
- /* Restore terminal settings. Errors will be dealt with later on. */
- tp->c_iflag = iflag;
- tp->c_cc[VMIN] = vmin;
- tcsetattr_stdin_TCSANOW(tp);
-}
-
-/* do_prompt - show login prompt, optionally preceded by /etc/issue contents */
-static void do_prompt(struct options *op)
-{
-#ifdef ISSUE
- print_login_issue(op->issue, op->tty);
-#endif
- print_login_prompt();
-}
-
-#ifdef HANDLE_ALLCAPS
-/* all_is_upcase - string contains upper case without lower case */
-/* returns 1 if true, 0 if false */
-static int all_is_upcase(const char *s)
-{
- while (*s)
- if (islower(*s++))
- return 0;
- return 1;
+ /* Restore terminal settings */
+ G.tty_attrs.c_cc[VMIN] = 1; /* restore to value set by init_tty_attrs */
+ set_tty_attrs();
}
-#endif
-/* get_logname - get user name, establish parity, speed, erase, kill, eol;
- * return NULL on BREAK, logname on success */
-static char *get_logname(char *logname, unsigned size_logname,
- struct options *op, struct chardata *cp)
+/* 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; /* 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 const char erase[][3] = {/* backspace-space-backspace */
- "\010\040\010", /* space parity */
- "\010\040\010", /* odd parity */
- "\210\240\210", /* even parity */
- "\010\040\010", /* 8 bit no parity */
- };
-
- /* NB: *cp is pre-initialized with init_chardata */
-
- /* Flush pending input (esp. after parsing or switching the baud rate). */
- sleep(1);
- ioctl(0, TCFLSH, TCIFLUSH); /* tcflush(0, TCIOFLUSH)? - same */
+ char c;
- /* Prompt for and read a login name. */
- logname[0] = '\0';
- while (!logname[0]) {
- /* Write issue file and prompt, with "parity" bit == 0. */
- do_prompt(op);
+ /* Flush pending input (esp. after parsing or switching the baud rate) */
+ usleep(100*1000); /* 0.1 sec */
+ tcflush(STDIN_FILENO, TCIFLUSH);
- /* Read name, watch for break, parity, erase, kill, end-of-line. */
- bp = logname;
- cp->eol = '\0';
- while (cp->eol == '\0') {
+ /* 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();
- /* Do not report trivial EINTR/EIO errors. */
+ /* 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("%s: read", op->tty);
- }
-
- /* BREAK. If we have speeds to try,
- * return NULL (will switch speeds and return here) */
- if (c == '\0' && op->numspeed > 1)
- return NULL;
-
- /* Do parity bit handling. */
- if (!(op->flags & F_LOCAL) && (c & 0x80)) { /* "parity" bit on? */
- bits = 1;
- mask = 1;
- while (mask & 0x7f) {
- if (mask & c)
- bits++; /* count "1" bits */
- mask <<= 1;
- }
- /* ... |= 2 - even, 1 - odd */
- cp->parity |= 2 - (bits & 1);
+ bb_simple_perror_msg_and_die(bb_msg_read_error);
}
- /* Do erase, kill and end-of-line processing. */
- ascval = c & 0x7f;
- switch (ascval) {
- case CR:
- case NL:
- *bp = '\0'; /* terminate logname */
- cp->eol = ascval; /* set end-of-line char */
- break;
- case BS:
- case DEL:
-#ifdef ANCIENT_BS_KILL_CHARS
- case '#':
-#endif
- cp->erase = ascval; /* set erase character */
- if (bp > logname) {
- full_write(STDOUT_FILENO, erase[cp->parity], 3);
+ 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'):
-#ifdef ANCIENT_BS_KILL_CHARS
- case '@':
-#endif
- cp->kill = ascval; /* set kill character */
- while (bp > logname) {
- full_write(STDOUT_FILENO, erase[cp->parity], 3);
+ 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 (ascval < ' ') {
+ if ((unsigned char)c < ' ') {
/* ignore garbage characters */
- } else if ((int)(bp - logname) >= size_logname - 1) {
- bb_error_msg_and_die("%s: input overrun", op->tty);
- } else {
- full_write(STDOUT_FILENO, &c, 1); /* echo the character */
- *bp++ = ascval; /* and store it */
+ } 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;
}
- }
- }
- /* Handle names with upper case and no lower case. */
-
-#ifdef HANDLE_ALLCAPS
- cp->capslock = all_is_upcase(logname);
- if (cp->capslock) {
- for (bp = logname; *bp; bp++)
- if (isupper(*bp))
- *bp = tolower(*bp); /* map name to lower case */
- }
-#endif
- return logname;
+ } /* end of get char loop */
+ got_logname: ;
+ } while (G.line_buf[0] == '\0'); /* while logname is empty */
+
+ return G.line_buf;
}
-/* termios_final - set the final tty mode bits */
-static void termios_final(struct options *op, struct termios *tp, struct chardata *cp)
+static void alarm_handler(int sig UNUSED_PARAM)
{
- /* 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 */
-// I bet most people go here - they use only 7-bit chars in usernames....
- 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;
-// FIXME: wtf? case 3: we saw both even and odd 8-bit bytes -
-// it's probably some umlauts etc, but definitely NOT 7-bit!!!
-// Entire parity detection madness here just begs for deletion...
- break;
- }
-
- /* Account for upper case without lower case. */
-#ifdef HANDLE_ALLCAPS
- if (cp->capslock) {
- tp->c_iflag |= IUCLC;
- tp->c_lflag |= XCASE;
- tp->c_oflag |= OLCUC;
- }
-#endif
- /* Optionally enable hardware flow control */
-#ifdef CRTSCTS
- if (op->flags & F_RTSCTS)
- tp->c_cflag |= CRTSCTS;
-#endif
+ finalize_tty_attrs();
+ _exit(EXIT_SUCCESS);
+}
- /* Finally, make the new settings effective */
- /* It's tcsetattr_stdin_TCSANOW() + error check */
- ioctl_or_perror_and_die(0, TCSETS, tp, "%s: TCSETS", op->tty);
+static void sleep10(void)
+{
+ sleep(10);
}
int getty_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int getty_main(int argc UNUSED_PARAM, char **argv)
{
int n;
- pid_t pid;
- char *fakehost = NULL; /* Fake hostname for ut_host */
- char *logname; /* login name, given to /bin/login */
- /* Merging these into "struct local" may _seem_ to reduce
- * parameter passing, but today's gcc will inline
- * statics which are called once anyway, so don't do that */
- struct chardata chardata; /* set by get_logname() */
- struct termios termios; /* terminal mode bits */
- struct options options;
-
- chardata = init_chardata;
-
- memset(&options, 0, sizeof(options));
- options.login = _PATH_LOGIN; /* default login program */
- options.tty = "tty1"; /* default tty line */
- options.initstring = ""; /* modem init string */
+ pid_t pid, tsid;
+ char *logname;
+
+ INIT_G();
+ G.login = _PATH_LOGIN; /* default login program */
#ifdef ISSUE
- options.issue = ISSUE; /* default issue file */
+ 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) {
+ //for debugging:
+ //bb_perror_msg_and_die("setsid failed:"
+ // " pid %d ppid %d"
+ // " sid %d pgid %d",
+ // pid, getppid(),
+ // getsid(0), getpgid(0));
+ bb_simple_perror_msg_and_die("setsid");
+ /*
+ * When we can end up here?
+ * Example: setsid() fails when run alone in interactive shell:
+ * # getty 115200 /dev/tty2
+ * because shell's child (getty) is put in a new process group.
+ * But doesn't fail if shell is not interactive
+ * (and therefore doesn't create process groups for pipes),
+ * or if getty is not the first process in the process group:
+ * # true | getty 115200 /dev/tty2
+ */
+ }
+ /* 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);
+ }
+ }
- /* Parse command-line arguments. */
- parse_args(argv, &options, &fakehost);
-
- logmode = LOGMODE_NONE;
-
- /* Create new session, lose controlling tty, if any */
- /* docs/ctty.htm says:
- * "This is allowed only when the current process
- * is not a process group leader" - is this a problem? */
- setsid();
- /* close stdio, and stray descriptors, just in case */
+ /* 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);
close(n--);
/* Logging. We want special flavor of error_msg_and_die */
- die_sleep = 10;
+ die_func = sleep10;
msg_eol = "\r\n";
/* most likely will internally use fd #3 in CLOEXEC mode: */
openlog(applet_name, LOG_PID, LOG_AUTH);
#endif
/* Open the tty as standard input, if it is not "-" */
- /* If it's not "-" and not taken yet, it will become our ctty */
debug("calling open_tty\n");
- open_tty(options.tty);
- ndelay_off(0);
+ open_tty();
+ ndelay_off(STDIN_FILENO);
debug("duping\n");
- xdup2(0, 1);
- xdup2(0, 2);
+ 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_simple_perror_msg_and_die("TIOCSCTTY");
+ }
+
+#ifdef __linux__
+ /* Make ourself a foreground process group within our session */
+ if (tcsetpgrp(STDIN_FILENO, pid) < 0)
+ bb_simple_perror_msg_and_die("tcsetpgrp");
+#endif
/*
* The following ioctl will fail if stdin is not a tty, but also when
* by patching the SunOS kernel variable "zsadtrlow" to a larger value;
* 5 seconds seems to be a good value.
*/
- /* tcgetattr() + error check */
- ioctl_or_perror_and_die(0, TCGETS, &termios, "%s: TCGETS", options.tty);
-
- pid = getpid();
-#ifdef __linux__
-// FIXME: do we need this? Otherwise "-" case seems to be broken...
- // /* Forcibly make fd 0 our controlling tty, even if another session
- // * has it as a ctty. (Another session loses ctty). */
- // ioctl(0, TIOCSCTTY, (void*)1);
- /* Make ourself a foreground process group within our session */
- tcsetpgrp(0, pid);
-#endif
+ if (tcgetattr(STDIN_FILENO, &G.tty_attrs) < 0)
+ bb_simple_perror_msg_and_die("tcgetattr");
/* Update the utmp file. This tty is ours now! */
- update_utmp(pid, LOGIN_PROCESS, options.tty, "LOGIN", fakehost);
+ update_utmp(pid, LOGIN_PROCESS, G.tty_name, "LOGIN", G.fakehost);
- /* Initialize the termios settings (raw mode, eight-bit, blocking i/o). */
- debug("calling termios_init\n");
- termios_init(&termios, options.speeds[0], &options);
+ /* 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 (options.flags & F_INITSTRING) {
+ if (option_mask32 & F_INITSTRING) {
debug("writing init string\n");
- /* todo: use xwrite_str? */
- full_write(STDOUT_FILENO, options.initstring, strlen(options.initstring));
+ full_write1_str(G.initstring);
}
/* Optionally detect the baud rate from the modem status message */
debug("before autobaud\n");
- if (options.flags & F_PARSE)
- auto_baud(line_buf, sizeof(line_buf), &termios);
+ if (option_mask32 & F_PARSE)
+ auto_baud();
/* Set the optional timer */
- alarm(options.timeout); /* if 0, alarm is not set */
+ signal(SIGALRM, alarm_handler);
+ alarm(G.timeout); /* if 0, alarm is not set */
/* Optionally wait for CR or LF before writing /etc/issue */
- if (options.flags & F_WAITCRLF) {
+ 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);
- ch &= 0x7f; /* strip "parity bit" */
if (ch == '\n' || ch == '\r')
break;
}
}
logname = NULL;
- if (!(options.flags & F_NOPROMPT)) {
- /* NB:termios_init already set line speed
- * to options.speeds[0] */
+ 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. */
+ /* Read the login name */
debug("reading login name\n");
- logname = get_logname(line_buf, sizeof(line_buf),
- &options, &chardata);
+ logname = get_logname();
if (logname)
break;
- /* we are here only if options.numspeed > 1 */
- baud_index = (baud_index + 1) % options.numspeed;
- cfsetispeed(&termios, options.speeds[baud_index]);
- cfsetospeed(&termios, options.speeds[baud_index]);
- tcsetattr_stdin_TCSANOW(&termios);
+ /* 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. */
+ /* Disable timer */
alarm(0);
- /* Finalize the termios settings. */
- termios_final(&options, &termios, &chardata);
-
- /* Now the newline character should be properly written. */
- full_write(STDOUT_FILENO, "\n", 1);
+ finalize_tty_attrs();
- /* Let the login program take care of password validation. */
+ /* 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. */
+ * and getty is not suid-root applet */
/* With -n, logname == NULL, and login will ask for username instead */
- BB_EXECLP(options.login, options.login, "--", logname, NULL);
- bb_error_msg_and_die("%s: can't exec %s", options.tty, options.login);
+ BB_EXECLP(G.login, G.login, "--", logname, (char *)0);
+ bb_error_msg_and_die("can't execute '%s'", G.login);
}