diff options
Diffstat (limited to 'mdk-stage1/ppp/pppd/tty.c')
| -rw-r--r-- | mdk-stage1/ppp/pppd/tty.c | 1164 |
1 files changed, 1164 insertions, 0 deletions
diff --git a/mdk-stage1/ppp/pppd/tty.c b/mdk-stage1/ppp/pppd/tty.c new file mode 100644 index 000000000..4db707968 --- /dev/null +++ b/mdk-stage1/ppp/pppd/tty.c @@ -0,0 +1,1164 @@ +/* + * tty.c - code for handling serial ports in pppd. + * + * Copyright (C) 2000 Paul Mackerras. + * All rights reserved. + * + * Portions Copyright (c) 1989 Carnegie Mellon University. + * All rights reserved. + * + * Redistribution and use in source and binary forms are permitted + * provided that the above copyright notice and this paragraph are + * duplicated in all such forms and that any documentation, + * advertising materials, and other materials related to such + * distribution and use acknowledge that the software was developed + * by Carnegie Mellon University. The name of the + * University may not be used to endorse or promote products derived + * from this software without specific prior written permission. + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED + * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. + */ + +#define RCSID "$Id$" + +#include <stdio.h> +#include <ctype.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <signal.h> +#include <errno.h> +#include <fcntl.h> +#include <syslog.h> +#include <netdb.h> +#include <utmp.h> +#include <pwd.h> +#include <setjmp.h> +#include <sys/param.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <sys/time.h> +#include <sys/resource.h> +#include <sys/stat.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/inet.h> + +#include "pppd.h" +#include "fsm.h" +#include "lcp.h" + +void tty_process_extra_options __P((void)); +void tty_check_options __P((void)); +int connect_tty __P((void)); +void disconnect_tty __P((void)); +void tty_close_fds __P((void)); +void cleanup_tty __P((void)); +void tty_do_send_config __P((int, u_int32_t, int, int)); + +static int setdevname __P((char *, char **, int)); +static int setspeed __P((char *, char **, int)); +static int setxonxoff __P((char **)); +static int setescape __P((char **)); +static void printescape __P((option_t *, void (*)(void *, char *,...),void *)); +static void finish_tty __P((void)); +static int start_charshunt __P((int, int)); +static void stop_charshunt __P((void *, int)); +static void charshunt_done __P((void *)); +static void charshunt __P((int, int, char *)); +static int record_write __P((FILE *, int code, u_char *buf, int nb, + struct timeval *)); +static int open_socket __P((char *)); +static void maybe_relock __P((void *, int)); + +static int pty_master; /* fd for master side of pty */ +static int pty_slave; /* fd for slave side of pty */ +static int real_ttyfd; /* fd for actual serial port (not pty) */ +static int ttyfd; /* Serial port file descriptor */ +static char speed_str[16]; /* Serial port speed as string */ + +mode_t tty_mode = (mode_t)-1; /* Original access permissions to tty */ +int baud_rate; /* Actual bits/second for serial device */ +char *callback_script; /* script for doing callback */ +int charshunt_pid; /* Process ID for charshunt */ +int locked; /* lock() has succeeded */ +struct stat devstat; /* result of stat() on devnam */ + +/* option variables */ +int crtscts = 0; /* Use hardware flow control */ +bool modem = 1; /* Use modem control lines */ +int inspeed = 0; /* Input/Output speed requested */ +bool lockflag = 0; /* Create lock file to lock the serial dev */ +char *initializer = NULL; /* Script to initialize physical link */ +char *connect_script = NULL; /* Script to establish physical link */ +char *disconnect_script = NULL; /* Script to disestablish physical link */ +char *welcomer = NULL; /* Script to run after phys link estab. */ +char *ptycommand = NULL; /* Command to run on other side of pty */ +bool notty = 0; /* Stdin/out is not a tty */ +char *record_file = NULL; /* File to record chars sent/received */ +int max_data_rate; /* max bytes/sec through charshunt */ +bool sync_serial = 0; /* Device is synchronous serial device */ +char *pty_socket = NULL; /* Socket to connect to pty */ +int using_pty = 0; /* we're allocating a pty as the device */ + +extern uid_t uid; +extern int kill_link; + +/* XXX */ +extern int privopen; /* don't lock, open device as root */ + +u_int32_t xmit_accm[8]; /* extended transmit ACCM */ + +/* option descriptors */ +option_t tty_options[] = { + /* device name must be first, or change connect_tty() below! */ + { "device name", o_wild, (void *) &setdevname, + "Serial port device name", + OPT_DEVNAM | OPT_PRIVFIX | OPT_NOARG | OPT_A2STRVAL | OPT_STATIC, + devnam}, + + { "tty speed", o_wild, (void *) &setspeed, + "Baud rate for serial port", + OPT_PRIO | OPT_NOARG | OPT_A2STRVAL | OPT_STATIC, speed_str }, + + { "lock", o_bool, &lockflag, + "Lock serial device with UUCP-style lock file", OPT_PRIO | 1 }, + { "nolock", o_bool, &lockflag, + "Don't lock serial device", OPT_PRIOSUB | OPT_PRIV }, + + { "init", o_string, &initializer, + "A program to initialize the device", OPT_PRIO | OPT_PRIVFIX }, + + { "connect", o_string, &connect_script, + "A program to set up a connection", OPT_PRIO | OPT_PRIVFIX }, + + { "disconnect", o_string, &disconnect_script, + "Program to disconnect serial device", OPT_PRIO | OPT_PRIVFIX }, + + { "welcome", o_string, &welcomer, + "Script to welcome client", OPT_PRIO | OPT_PRIVFIX }, + + { "pty", o_string, &ptycommand, + "Script to run on pseudo-tty master side", + OPT_PRIO | OPT_PRIVFIX | OPT_DEVNAM }, + + { "notty", o_bool, ¬ty, + "Input/output is not a tty", OPT_DEVNAM | 1 }, + + { "socket", o_string, &pty_socket, + "Send and receive over socket, arg is host:port", + OPT_PRIO | OPT_DEVNAM }, + + { "record", o_string, &record_file, + "Record characters sent/received to file", OPT_PRIO }, + + { "crtscts", o_int, &crtscts, + "Set hardware (RTS/CTS) flow control", + OPT_PRIO | OPT_NOARG | OPT_VAL(1) }, + { "cdtrcts", o_int, &crtscts, + "Set alternate hardware (DTR/CTS) flow control", + OPT_PRIOSUB | OPT_NOARG | OPT_VAL(2) }, + { "nocrtscts", o_int, &crtscts, + "Disable hardware flow control", + OPT_PRIOSUB | OPT_NOARG | OPT_VAL(-1) }, + { "-crtscts", o_int, &crtscts, + "Disable hardware flow control", + OPT_PRIOSUB | OPT_ALIAS | OPT_NOARG | OPT_VAL(-1) }, + { "nocdtrcts", o_int, &crtscts, + "Disable hardware flow control", + OPT_PRIOSUB | OPT_ALIAS | OPT_NOARG | OPT_VAL(-1) }, + { "xonxoff", o_special_noarg, (void *)setxonxoff, + "Set software (XON/XOFF) flow control", OPT_PRIOSUB }, + + { "modem", o_bool, &modem, + "Use modem control lines", OPT_PRIO | 1 }, + { "local", o_bool, &modem, + "Don't use modem control lines", OPT_PRIOSUB | 0 }, + + { "sync", o_bool, &sync_serial, + "Use synchronous HDLC serial encoding", 1 }, + + { "datarate", o_int, &max_data_rate, + "Maximum data rate in bytes/sec (with pty, notty or record option)", + OPT_PRIO }, + + { "escape", o_special, (void *)setescape, + "List of character codes to escape on transmission", + OPT_A2PRINTER, (void *)printescape }, + + { NULL } +}; + + +struct channel tty_channel = { + tty_options, + &tty_process_extra_options, + &tty_check_options, + &connect_tty, + &disconnect_tty, + &tty_establish_ppp, + &tty_disestablish_ppp, + &tty_do_send_config, + &tty_recv_config, + &cleanup_tty, + &tty_close_fds +}; + +/* + * setspeed - Set the serial port baud rate. + * If doit is 0, the call is to check whether this option is + * potentially a speed value. + */ +static int +setspeed(arg, argv, doit) + char *arg; + char **argv; + int doit; +{ + char *ptr; + int spd; + + spd = strtol(arg, &ptr, 0); + if (ptr == arg || *ptr != 0 || spd == 0) + return 0; + if (doit) { + inspeed = spd; + slprintf(speed_str, sizeof(speed_str), "%d", spd); + } + return 1; +} + + +/* + * setdevname - Set the device name. + * If doit is 0, the call is to check whether this option is + * potentially a device name. + */ +static int +setdevname(cp, argv, doit) + char *cp; + char **argv; + int doit; +{ + struct stat statbuf; + char dev[MAXPATHLEN]; + + if (*cp == 0) + return 0; + + if (strncmp("/dev/", cp, 5) != 0) { + strlcpy(dev, "/dev/", sizeof(dev)); + strlcat(dev, cp, sizeof(dev)); + cp = dev; + } + + /* + * Check if there is a character device by this name. + */ + if (stat(cp, &statbuf) < 0) { + if (!doit) + return errno != ENOENT; + option_error("Couldn't stat %s: %m", cp); + return 0; + } + if (!S_ISCHR(statbuf.st_mode)) { + if (doit) + option_error("%s is not a character device", cp); + return 0; + } + + if (doit) { + strlcpy(devnam, cp, sizeof(devnam)); + devstat = statbuf; + default_device = 0; + } + + return 1; +} + +static int +setxonxoff(argv) + char **argv; +{ + lcp_wantoptions[0].asyncmap |= 0x000A0000; /* escape ^S and ^Q */ + lcp_wantoptions[0].neg_asyncmap = 1; + + crtscts = -2; + return 1; +} + +/* + * setescape - add chars to the set we escape on transmission. + */ +static int +setescape(argv) + char **argv; +{ + int n, ret; + char *p, *endp; + + p = *argv; + ret = 1; + while (*p) { + n = strtol(p, &endp, 16); + if (p == endp) { + option_error("escape parameter contains invalid hex number '%s'", + p); + return 0; + } + p = endp; + if (n < 0 || n == 0x5E || n > 0xFF) { + option_error("can't escape character 0x%x", n); + ret = 0; + } else + xmit_accm[n >> 5] |= 1 << (n & 0x1F); + while (*p == ',' || *p == ' ') + ++p; + } + lcp_allowoptions[0].asyncmap = xmit_accm[0]; + return ret; +} + +static void +printescape(opt, printer, arg) + option_t *opt; + void (*printer) __P((void *, char *, ...)); + void *arg; +{ + int n; + int first = 1; + + for (n = 0; n < 256; ++n) { + if (n == 0x7d) + n += 2; /* skip 7d, 7e */ + if (xmit_accm[n >> 5] & (1 << (n & 0x1f))) { + if (!first) + printer(arg, ","); + else + first = 0; + printer(arg, "%x", n); + } + } + if (first) + printer(arg, "oops # nothing escaped"); +} + +/* + * tty_init - do various tty-related initializations. + */ +void tty_init() +{ + add_notifier(&pidchange, maybe_relock, 0); + the_channel = &tty_channel; + xmit_accm[3] = 0x60000000; +} + +/* + * tty_process_extra_options - work out which tty device we are using + * and read its options file. + */ +void tty_process_extra_options() +{ + using_pty = notty || ptycommand != NULL || pty_socket != NULL; + if (using_pty) + return; + if (default_device) { + char *p; + if (!isatty(0) || (p = ttyname(0)) == NULL) { + option_error("no device specified and stdin is not a tty"); + exit(EXIT_OPTION_ERROR); + } + strlcpy(devnam, p, sizeof(devnam)); + if (stat(devnam, &devstat) < 0) + fatal("Couldn't stat default device %s: %m", devnam); + } + + + /* + * Parse the tty options file. + * The per-tty options file should not change + * ptycommand, pty_socket, notty or devnam. + * options_for_tty doesn't override options set on the command line, + * except for some privileged options. + */ + if (!options_for_tty()) + exit(EXIT_OPTION_ERROR); +} + +/* + * tty_check_options - do consistency checks on the options we were given. + */ +void +tty_check_options() +{ + struct stat statbuf; + int fdflags; + + if (demand && connect_script == 0) { + option_error("connect script is required for demand-dialling\n"); + exit(EXIT_OPTION_ERROR); + } + /* default holdoff to 0 if no connect script has been given */ + if (connect_script == 0 && !holdoff_specified) + holdoff = 0; + + if (using_pty) { + if (!default_device) { + option_error("%s option precludes specifying device name", + notty? "notty": "pty"); + exit(EXIT_OPTION_ERROR); + } + if (ptycommand != NULL && notty) { + option_error("pty option is incompatible with notty option"); + exit(EXIT_OPTION_ERROR); + } + if (pty_socket != NULL && (ptycommand != NULL || notty)) { + option_error("socket option is incompatible with pty and notty"); + exit(EXIT_OPTION_ERROR); + } + default_device = notty; + lockflag = 0; + modem = 0; + if (notty && log_to_fd <= 1) + log_to_fd = -1; + } else { + /* + * If the user has specified a device which is the same as + * the one on stdin, pretend they didn't specify any. + * If the device is already open read/write on stdin, + * we assume we don't need to lock it, and we can open it + * as root. + */ + if (fstat(0, &statbuf) >= 0 && S_ISCHR(statbuf.st_mode) + && statbuf.st_rdev == devstat.st_rdev) { + default_device = 1; + fdflags = fcntl(0, F_GETFL); + if (fdflags != -1 && (fdflags & O_ACCMODE) == O_RDWR) + privopen = 1; + } + } + if (default_device) + nodetach = 1; + + /* + * Don't send log messages to the serial port, it tends to + * confuse the peer. :-) + */ + if (log_to_fd >= 0 && fstat(log_to_fd, &statbuf) >= 0 + && S_ISCHR(statbuf.st_mode) && statbuf.st_rdev == devstat.st_rdev) + log_to_fd = -1; +} + +/* + * connect_tty - get the serial port ready to start doing PPP. + * That is, open the serial port, set its speed and mode, and run + * the connector and/or welcomer. + */ +int connect_tty() +{ + char *connector; + int fdflags; + struct stat statbuf; + char numbuf[16]; + + /* + * Get a pty master/slave pair if the pty, notty, socket, + * or record options were specified. + */ + strlcpy(ppp_devnam, devnam, sizeof(ppp_devnam)); + pty_master = -1; + pty_slave = -1; + real_ttyfd = -1; + if (using_pty || record_file != NULL) { + if (!get_pty(&pty_master, &pty_slave, ppp_devnam, uid)) { + error("Couldn't allocate pseudo-tty"); + status = EXIT_FATAL_ERROR; + return -1; + } + set_up_tty(pty_slave, 1); + } + + /* + * Lock the device if we've been asked to. + */ + status = EXIT_LOCK_FAILED; + if (lockflag && !privopen) { + if (lock(devnam) < 0) + return -1; + locked = 1; + } + + /* + * Open the serial device and set it up to be the ppp interface. + * First we open it in non-blocking mode so we can set the + * various termios flags appropriately. If we aren't dialling + * out and we want to use the modem lines, we reopen it later + * in order to wait for the carrier detect signal from the modem. + */ + hungup = 0; + kill_link = 0; + connector = doing_callback? callback_script: connect_script; + if (devnam[0] != 0) { + for (;;) { + /* If the user specified the device name, become the + user before opening it. */ + int err, prio; + + prio = privopen? OPRIO_ROOT: tty_options[0].priority; + if (prio < OPRIO_ROOT) + seteuid(uid); + ttyfd = open(devnam, O_NONBLOCK | O_RDWR, 0); + err = errno; + if (prio < OPRIO_ROOT) + seteuid(0); + if (ttyfd >= 0) + break; + errno = err; + if (err != EINTR) { + error("Failed to open %s: %m", devnam); + status = EXIT_OPEN_FAILED; + } + if (!persist || err != EINTR) + return -1; + } + real_ttyfd = ttyfd; + if ((fdflags = fcntl(ttyfd, F_GETFL)) == -1 + || fcntl(ttyfd, F_SETFL, fdflags & ~O_NONBLOCK) < 0) + warn("Couldn't reset non-blocking mode on device: %m"); + + /* + * Do the equivalent of `mesg n' to stop broadcast messages. + */ + if (fstat(ttyfd, &statbuf) < 0 + || fchmod(ttyfd, statbuf.st_mode & ~(S_IWGRP | S_IWOTH)) < 0) { + warn("Couldn't restrict write permissions to %s: %m", devnam); + } else + tty_mode = statbuf.st_mode; + + /* + * Set line speed, flow control, etc. + * If we have a non-null connection or initializer script, + * on most systems we set CLOCAL for now so that we can talk + * to the modem before carrier comes up. But this has the + * side effect that we might miss it if CD drops before we + * get to clear CLOCAL below. On systems where we can talk + * successfully to the modem with CLOCAL clear and CD down, + * we could clear CLOCAL at this point. + */ + set_up_tty(ttyfd, ((connector != NULL && connector[0] != 0) + || initializer != NULL)); + } + + /* + * If the pty, socket, notty and/or record option was specified, + * start up the character shunt now. + */ + status = EXIT_PTYCMD_FAILED; + if (ptycommand != NULL) { + if (record_file != NULL) { + int ipipe[2], opipe[2], ok; + + if (pipe(ipipe) < 0 || pipe(opipe) < 0) + fatal("Couldn't create pipes for record option: %m"); + ok = device_script(ptycommand, opipe[0], ipipe[1], 1) == 0 + && start_charshunt(ipipe[0], opipe[1]); + close(ipipe[0]); + close(ipipe[1]); + close(opipe[0]); + close(opipe[1]); + if (!ok) + return -1; + } else { + if (device_script(ptycommand, pty_master, pty_master, 1) < 0) + return -1; + ttyfd = pty_slave; + close(pty_master); + pty_master = -1; + } + } else if (pty_socket != NULL) { + int fd = open_socket(pty_socket); + if (fd < 0) + return -1; + if (!start_charshunt(fd, fd)) + return -1; + } else if (notty) { + if (!start_charshunt(0, 1)) + return -1; + } else if (record_file != NULL) { + if (!start_charshunt(ttyfd, ttyfd)) + return -1; + } + + /* run connection script */ + if ((connector && connector[0]) || initializer) { + if (real_ttyfd != -1) { + /* XXX do this if doing_callback == CALLBACK_DIALIN? */ + if (!default_device && modem) { + setdtr(real_ttyfd, 0); /* in case modem is off hook */ + sleep(1); + setdtr(real_ttyfd, 1); + } + } + + if (initializer && initializer[0]) { + if (device_script(initializer, ttyfd, ttyfd, 0) < 0) { + error("Initializer script failed"); + status = EXIT_INIT_FAILED; + return -1; + } + if (kill_link) { + disconnect_tty(); + return -1; + } + info("Serial port initialized."); + } + + if (connector && connector[0]) { + if (device_script(connector, ttyfd, ttyfd, 0) < 0) { + error("Connect script failed"); + status = EXIT_CONNECT_FAILED; + return -1; + } + if (kill_link) { + disconnect_tty(); + return -1; + } + info("Serial connection established."); + } + + /* set line speed, flow control, etc.; + clear CLOCAL if modem option */ + if (real_ttyfd != -1) + set_up_tty(real_ttyfd, 0); + + if (doing_callback == CALLBACK_DIALIN) + connector = NULL; + } + + /* reopen tty if necessary to wait for carrier */ + if (connector == NULL && modem && devnam[0] != 0) { + int i; + for (;;) { + if ((i = open(devnam, O_RDWR)) >= 0) + break; + if (errno != EINTR) { + error("Failed to reopen %s: %m", devnam); + status = EXIT_OPEN_FAILED; + } + if (!persist || errno != EINTR || hungup || kill_link) + return -1; + } + close(i); + } + + slprintf(numbuf, sizeof(numbuf), "%d", baud_rate); + script_setenv("SPEED", numbuf, 0); + + /* run welcome script, if any */ + if (welcomer && welcomer[0]) { + if (device_script(welcomer, ttyfd, ttyfd, 0) < 0) + warn("Welcome script failed"); + } + + /* + * If we are initiating this connection, wait for a short + * time for something from the peer. This can avoid bouncing + * our packets off his tty before he has it set up. + */ + if (connector != NULL || ptycommand != NULL) + listen_time = connect_delay; + + return ttyfd; +} + + +void disconnect_tty() +{ + if (disconnect_script == NULL || hungup) + return; + if (real_ttyfd >= 0) + set_up_tty(real_ttyfd, 1); + if (device_script(disconnect_script, ttyfd, ttyfd, 0) < 0) { + warn("disconnect script failed"); + } else { + info("Serial link disconnected."); + } +} + +void tty_close_fds() +{ + if (pty_master >= 0) + close(pty_master); + if (pty_slave >= 0) + close(pty_slave); + if (real_ttyfd >= 0) { + close(real_ttyfd); + real_ttyfd = -1; + } + /* N.B. ttyfd will == either pty_slave or real_ttyfd */ +} + +void cleanup_tty() +{ + if (real_ttyfd >= 0) + finish_tty(); + tty_close_fds(); + if (locked) { + unlock(); + locked = 0; + } +} + +/* + * tty_do_send_config - set transmit-side PPP configuration. + * We set the extended transmit ACCM here as well. + */ +void +tty_do_send_config(mtu, accm, pcomp, accomp) + int mtu; + u_int32_t accm; + int pcomp, accomp; +{ + tty_set_xaccm(xmit_accm); + tty_send_config(mtu, accm, pcomp, accomp); +} + +/* + * finish_tty - restore the terminal device to its original settings + */ +static void +finish_tty() +{ + /* drop dtr to hang up */ + if (!default_device && modem) { + setdtr(real_ttyfd, 0); + /* + * This sleep is in case the serial port has CLOCAL set by default, + * and consequently will reassert DTR when we close the device. + */ + sleep(1); + } + + restore_tty(real_ttyfd); + + if (tty_mode != (mode_t) -1) { + if (fchmod(real_ttyfd, tty_mode) != 0) { + /* XXX if devnam is a symlink, this will change the link */ + chmod(devnam, tty_mode); + } + } + + close(real_ttyfd); + real_ttyfd = -1; +} + +/* + * maybe_relock - our PID has changed, maybe update the lock file. + */ +static void +maybe_relock(arg, pid) + void *arg; + int pid; +{ + if (locked) + relock(pid); +} + +/* + * open_socket - establish a stream socket connection to the nominated + * host and port. + */ +static int +open_socket(dest) + char *dest; +{ + char *sep, *endp = NULL; + int sock, port = -1; + u_int32_t host; + struct hostent *hent; + struct sockaddr_in sad; + + /* parse host:port and resolve host to an IP address */ + sep = strchr(dest, ':'); + if (sep != NULL) + port = strtol(sep+1, &endp, 10); + if (port < 0 || endp == sep+1 || sep == dest) { + error("Can't parse host:port for socket destination"); + return -1; + } + *sep = 0; + host = inet_addr(dest); + if (host == (u_int32_t) -1) { + hent = gethostbyname(dest); + if (hent == NULL) { + error("%s: unknown host in socket option", dest); + *sep = ':'; + return -1; + } + host = *(u_int32_t *)(hent->h_addr_list[0]); + } + *sep = ':'; + + /* get a socket and connect it to the other end */ + sock = socket(PF_INET, SOCK_STREAM, 0); + if (sock < 0) { + error("Can't create socket: %m"); + return -1; + } + memset(&sad, 0, sizeof(sad)); + sad.sin_family = AF_INET; + sad.sin_port = htons(port); + sad.sin_addr.s_addr = host; + if (connect(sock, (struct sockaddr *)&sad, sizeof(sad)) < 0) { + error("Can't connect to %s: %m", dest); + close(sock); + return -1; + } + + return sock; +} + + +/* + * start_charshunt - create a child process to run the character shunt. + */ +static int +start_charshunt(ifd, ofd) + int ifd, ofd; +{ + int cpid; + + cpid = fork(); + if (cpid == -1) { + error("Can't fork process for character shunt: %m"); + return 0; + } + if (cpid == 0) { + /* child */ + close(pty_slave); + setuid(uid); + if (getuid() != uid) + fatal("setuid failed"); + setgid(getgid()); + if (!nodetach) + log_to_fd = -1; + charshunt(ifd, ofd, record_file); + exit(0); + } + charshunt_pid = cpid; + add_notifier(&sigreceived, stop_charshunt, 0); + close(pty_master); + pty_master = -1; + ttyfd = pty_slave; + record_child(cpid, "pppd (charshunt)", charshunt_done, NULL); + return 1; +} + +static void +charshunt_done(arg) + void *arg; +{ + charshunt_pid = 0; +} + +static void +stop_charshunt(arg, sig) + void *arg; + int sig; +{ + if (charshunt_pid) + kill(charshunt_pid, (sig == SIGINT? sig: SIGTERM)); +} + +/* + * charshunt - the character shunt, which passes characters between + * the pty master side and the serial port (or stdin/stdout). + * This runs as the user (not as root). + * (We assume ofd >= ifd which is true the way this gets called. :-). + */ +static void +charshunt(ifd, ofd, record_file) + int ifd, ofd; + char *record_file; +{ + int n, nfds; + fd_set ready, writey; + u_char *ibufp, *obufp; + int nibuf, nobuf; + int flags; + int pty_readable, stdin_readable; + struct timeval lasttime; + FILE *recordf = NULL; + int ilevel, olevel, max_level; + struct timeval levelt, tout, *top; + extern u_char inpacket_buf[]; + + /* + * Reset signal handlers. + */ + signal(SIGHUP, SIG_IGN); /* Hangup */ + signal(SIGINT, SIG_DFL); /* Interrupt */ + signal(SIGTERM, SIG_DFL); /* Terminate */ + signal(SIGCHLD, SIG_DFL); + signal(SIGUSR1, SIG_DFL); + signal(SIGUSR2, SIG_DFL); + signal(SIGABRT, SIG_DFL); + signal(SIGALRM, SIG_DFL); + signal(SIGFPE, SIG_DFL); + signal(SIGILL, SIG_DFL); + signal(SIGPIPE, SIG_DFL); + signal(SIGQUIT, SIG_DFL); + signal(SIGSEGV, SIG_DFL); +#ifdef SIGBUS + signal(SIGBUS, SIG_DFL); +#endif +#ifdef SIGEMT + signal(SIGEMT, SIG_DFL); +#endif +#ifdef SIGPOLL + signal(SIGPOLL, SIG_DFL); +#endif +#ifdef SIGPROF + signal(SIGPROF, SIG_DFL); +#endif +#ifdef SIGSYS + signal(SIGSYS, SIG_DFL); +#endif +#ifdef SIGTRAP + signal(SIGTRAP, SIG_DFL); +#endif +#ifdef SIGVTALRM + signal(SIGVTALRM, SIG_DFL); +#endif +#ifdef SIGXCPU + signal(SIGXCPU, SIG_DFL); +#endif +#ifdef SIGXFSZ + signal(SIGXFSZ, SIG_DFL); +#endif + + /* + * Open the record file if required. + */ + if (record_file != NULL) { + recordf = fopen(record_file, "a"); + if (recordf == NULL) + error("Couldn't create record file %s: %m", record_file); + } + + /* set all the fds to non-blocking mode */ + flags = fcntl(pty_master, F_GETFL); + if (flags == -1 + || fcntl(pty_master, F_SETFL, flags | O_NONBLOCK) == -1) + warn("couldn't set pty master to nonblock: %m"); + flags = fcntl(ifd, F_GETFL); + if (flags == -1 + || fcntl(ifd, F_SETFL, flags | O_NONBLOCK) == -1) + warn("couldn't set %s to nonblock: %m", (ifd==0? "stdin": "tty")); + if (ofd != ifd) { + flags = fcntl(ofd, F_GETFL); + if (flags == -1 + || fcntl(ofd, F_SETFL, flags | O_NONBLOCK) == -1) + warn("couldn't set stdout to nonblock: %m"); + } + + nibuf = nobuf = 0; + ibufp = obufp = NULL; + pty_readable = stdin_readable = 1; + + ilevel = olevel = 0; + gettimeofday(&levelt, NULL); + if (max_data_rate) { + max_level = max_data_rate / 10; + if (max_level < 100) + max_level = 100; + } else + max_level = PPP_MRU + PPP_HDRLEN + 1; + + nfds = (ofd > pty_master? ofd: pty_master) + 1; + if (recordf != NULL) { + gettimeofday(&lasttime, NULL); + putc(7, recordf); /* put start marker */ + putc(lasttime.tv_sec >> 24, recordf); + putc(lasttime.tv_sec >> 16, recordf); + putc(lasttime.tv_sec >> 8, recordf); + putc(lasttime.tv_sec, recordf); + lasttime.tv_usec = 0; + } + + while (nibuf != 0 || nobuf != 0 || pty_readable || stdin_readable) { + top = 0; + tout.tv_sec = 0; + tout.tv_usec = 10000; + FD_ZERO(&ready); + FD_ZERO(&writey); + if (nibuf != 0) { + if (ilevel >= max_level) + top = &tout; + else + FD_SET(pty_master, &writey); + } else if (stdin_readable) + FD_SET(ifd, &ready); + if (nobuf != 0) { + if (olevel >= max_level) + top = &tout; + else + FD_SET(ofd, &writey); + } else if (pty_readable) + FD_SET(pty_master, &ready); + if (select(nfds, &ready, &writey, NULL, top) < 0) { + if (errno != EINTR) + fatal("select"); + continue; + } + if (max_data_rate) { + double dt; + int nbt; + struct timeval now; + + gettimeofday(&now, NULL); + dt = (now.tv_sec - levelt.tv_sec + + (now.tv_usec - levelt.tv_usec) / 1e6); + nbt = (int)(dt * max_data_rate); + ilevel = (nbt < 0 || nbt > ilevel)? 0: ilevel - nbt; + olevel = (nbt < 0 || nbt > olevel)? 0: olevel - nbt; + levelt = now; + } else + ilevel = olevel = 0; + if (FD_ISSET(ifd, &ready)) { + ibufp = inpacket_buf; + nibuf = read(ifd, ibufp, PPP_MRU + PPP_HDRLEN); + if (nibuf < 0 && errno == EIO) + nibuf = 0; + if (nibuf < 0) { + if (!(errno == EINTR || errno == EAGAIN)) { + error("Error reading standard input: %m"); + break; + } + nibuf = 0; + } else if (nibuf == 0) { + /* end of file from stdin */ + stdin_readable = 0; + /* do a 0-length write, hopefully this will generate + an EOF (hangup) on the slave side. */ + write(pty_master, inpacket_buf, 0); + if (recordf) + if (!record_write(recordf, 4, NULL, 0, &lasttime)) + recordf = NULL; + } else { + FD_SET(pty_master, &writey); + if (recordf) + if (!record_write(recordf, 2, ibufp, nibuf, &lasttime)) + recordf = NULL; + } + } + if (FD_ISSET(pty_master, &ready)) { + obufp = outpacket_buf; + nobuf = read(pty_master, obufp, PPP_MRU + PPP_HDRLEN); + if (nobuf < 0 && errno == EIO) + nobuf = 0; + if (nobuf < 0) { + if (!(errno == EINTR || errno == EAGAIN)) { + error("Error reading pseudo-tty master: %m"); + break; + } + nobuf = 0; + } else if (nobuf == 0) { + /* end of file from the pty - slave side has closed */ + pty_readable = 0; + stdin_readable = 0; /* pty is not writable now */ + nibuf = 0; + close(ofd); + if (recordf) + if (!record_write(recordf, 3, NULL, 0, &lasttime)) + recordf = NULL; + } else { + FD_SET(ofd, &writey); + if (recordf) + if (!record_write(recordf, 1, obufp, nobuf, &lasttime)) + recordf = NULL; + } + } + if (FD_ISSET(ofd, &writey)) { + n = nobuf; + if (olevel + n > max_level) + n = max_level - olevel; + n = write(ofd, obufp, n); + if (n < 0) { + if (errno == EIO) { + pty_readable = 0; + nobuf = 0; + } else if (errno != EAGAIN && errno != EINTR) { + error("Error writing standard output: %m"); + break; + } + } else { + obufp += n; + nobuf -= n; + olevel += n; + } + } + if (FD_ISSET(pty_master, &writey)) { + n = nibuf; + if (ilevel + n > max_level) + n = max_level - ilevel; + n = write(pty_master, ibufp, n); + if (n < 0) { + if (errno == EIO) { + stdin_readable = 0; + nibuf = 0; + } else if (errno != EAGAIN && errno != EINTR) { + error("Error writing pseudo-tty master: %m"); + break; + } + } else { + ibufp += n; + nibuf -= n; + ilevel += n; + } + } + } + exit(0); +} + +static int +record_write(f, code, buf, nb, tp) + FILE *f; + int code; + u_char *buf; + int nb; + struct timeval *tp; +{ + struct timeval now; + int diff; + + gettimeofday(&now, NULL); + now.tv_usec /= 100000; /* actually 1/10 s, not usec now */ + diff = (now.tv_sec - tp->tv_sec) * 10 + (now.tv_usec - tp->tv_usec); + if (diff > 0) { + if (diff > 255) { + putc(5, f); + putc(diff >> 24, f); + putc(diff >> 16, f); + putc(diff >> 8, f); + putc(diff, f); + } else { + putc(6, f); + putc(diff, f); + } + *tp = now; + } + putc(code, f); + if (buf != NULL) { + putc(nb >> 8, f); + putc(nb, f); + fwrite(buf, nb, 1, f); + } + fflush(f); + if (ferror(f)) { + error("Error writing record file: %m"); + return 0; + } + return 1; +} |