X-Git-Url: http://git.ozlabs.org/?p=ppp.git;a=blobdiff_plain;f=pppd%2Fmain.c;h=dbeaeac0ce400338301c9e9cd968541be41fc00b;hp=2f17a69ed0d6933a3f2bfcbfdb374249cbc2f1b8;hb=4e3c66a04c0b86108858081d434bc45983471990;hpb=9678d8e116c5f9ae854b9f744ebf3f6aae85d16a diff --git a/pppd/main.c b/pppd/main.c index 2f17a69..dbeaeac 100644 --- a/pppd/main.c +++ b/pppd/main.c @@ -18,7 +18,7 @@ */ #ifndef lint -static char rcsid[] = "$Id: main.c,v 1.41 1997/04/30 05:54:52 paulus Exp $"; +static char rcsid[] = "$Id: main.c,v 1.51 1998/11/07 06:59:28 paulus Exp $"; #endif #include @@ -33,6 +33,7 @@ static char rcsid[] = "$Id: main.c,v 1.41 1997/04/30 05:54:52 paulus Exp $"; #include #include #include +#include #include #include #include @@ -40,7 +41,6 @@ static char rcsid[] = "$Id: main.c,v 1.41 1997/04/30 05:54:52 paulus Exp $"; #include #include #include -#include #include "pppd.h" #include "magic.h" @@ -69,7 +69,7 @@ extern char *strerror(); #endif /* interface vars */ -char ifname[IFNAMSIZ]; /* Interface name */ +char ifname[32]; /* Interface name */ int ifunit; /* Interface unit number */ char *progname; /* Name of this program */ @@ -86,11 +86,17 @@ int baud_rate; /* Actual bits/second for serial device */ int hungup; /* terminal has been hung up */ int privileged; /* we're running as real uid root */ int need_holdoff; /* need holdoff period before restarting */ +int detached; /* have detached from terminal */ int phase; /* where the link is at */ int kill_link; int open_ccp_flag; -int redirect_stderr; /* Connector's stderr should go to file */ + +static int waiting; +static jmp_buf sigjmp; + +char **script_env; /* Env. variable values for scripts */ +int s_env_nalloc; /* # words avail at script_env */ u_char outpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for outgoing packet */ u_char inpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for incoming packet */ @@ -103,6 +109,7 @@ char *no_ppp_msg = "Sorry - this system lacks PPP kernel support\n"; /* Prototypes for procedures local to this file. */ +static void create_pidfile __P((void)); static void cleanup __P((void)); static void close_tty __P((void)); static void get_input __P((void)); @@ -161,15 +168,15 @@ main(argc, argv) int argc; char *argv[]; { - int i, nonblock, fdflags; + int i, fdflags; struct sigaction sa; - FILE *pidfile; char *p; struct passwd *pw; struct timeval timo; sigset_t mask; struct protent *protp; struct stat statbuf; + char numbuf[16]; phase = PHASE_INITIALIZE; p = ttyname(0); @@ -177,6 +184,8 @@ main(argc, argv) strcpy(devnam, p); strcpy(default_devnam, devnam); + script_env = NULL; + /* Initialize syslog facilities */ #ifdef ULTRIX openlog("pppd", LOG_PID); @@ -187,12 +196,14 @@ main(argc, argv) if (gethostname(hostname, MAXNAMELEN) < 0 ) { option_error("Couldn't get hostname: %m"); - die(1); + exit(1); } hostname[MAXNAMELEN-1] = 0; uid = getuid(); privileged = uid == 0; + sprintf(numbuf, "%d", uid); + script_setenv("ORIG_UID", numbuf); /* * Initialize to the standard option set, then parse, in order, @@ -201,7 +212,7 @@ main(argc, argv) */ for (i = 0; (protp = protocols[i]) != NULL; ++i) (*protp->init)(0); - + progname = *argv; if (!options_from_file(_PATH_SYSOPTIONS, !privileged, 0, 1) @@ -218,7 +229,7 @@ main(argc, argv) if (geteuid() != 0) { option_error("must be root to run %s, since it is not setuid-root", argv[0]); - die(1); + exit(1); } if (!ppp_available()) { @@ -229,23 +240,29 @@ main(argc, argv) /* * Check that the options given are valid and consistent. */ - sys_check_options(); + if (!sys_check_options()) + exit(1); auth_check_options(); for (i = 0; (protp = protocols[i]) != NULL; ++i) if (protp->check_options != NULL) (*protp->check_options)(); if (demand && connector == 0) { - option_error("connect script required for demand-dialling\n"); + option_error("connect script is required for demand-dialling\n"); exit(1); } + script_setenv("DEVICE", devnam); + sprintf(numbuf, "%d", baud_rate); + script_setenv("SPEED", numbuf); + /* * If the user has specified the default device name explicitly, * pretend they hadn't. */ if (!default_device && strcmp(devnam, default_devnam) == 0) default_device = 1; - redirect_stderr = !nodetach || default_device; + if (default_device) + nodetach = 1; /* * Initialize system-dependent stuff and magic number package. @@ -259,10 +276,8 @@ main(argc, argv) * Detach ourselves from the terminal, if required, * and identify who is running us. */ - if (!default_device && !nodetach && daemon(0, 0) < 0) { - perror("Couldn't detach from controlling terminal"); - exit(1); - } + if (!nodetach && !updetach) + detach(); pid = getpid(); p = getlogin(); if (p == NULL) { @@ -285,12 +300,13 @@ main(argc, argv) sigaddset(&mask, SIGINT); sigaddset(&mask, SIGTERM); sigaddset(&mask, SIGCHLD); + sigaddset(&mask, SIGUSR2); #define SIGNAL(s, handler) { \ sa.sa_handler = handler; \ if (sigaction(s, &sa, NULL) < 0) { \ syslog(LOG_ERR, "Couldn't establish signal handler (%d): %m", s); \ - die(1); \ + exit(1); \ } \ } @@ -350,6 +366,9 @@ main(argc, argv) */ signal(SIGPIPE, SIG_IGN); + waiting = 0; + sigprocmask(SIG_BLOCK, &mask, NULL); + /* * If we're doing dial-on-demand, set up the interface now. */ @@ -361,16 +380,9 @@ main(argc, argv) syslog(LOG_INFO, "Using interface ppp%d", ifunit); (void) sprintf(ifname, "ppp%d", ifunit); + script_setenv("IFNAME", ifname); - /* write pid to file */ - (void) sprintf(pidfilename, "%s%s.pid", _PATH_VARRUN, ifname); - if ((pidfile = fopen(pidfilename, "w")) != NULL) { - fprintf(pidfile, "%d\n", pid); - (void) fclose(pidfile); - } else { - syslog(LOG_ERR, "Failed to create pid file %s: %m", pidfilename); - pidfilename[0] = 0; - } + create_pidfile(); /* write pid to file */ /* * Configure the interface and mark it up, etc. @@ -390,17 +402,25 @@ main(argc, argv) kill_link = 0; demand_unblock(); for (;;) { - wait_loop_output(timeleft(&timo)); + if (setjmp(sigjmp) == 0) { + waiting = 1; + sigprocmask(SIG_UNBLOCK, &mask, NULL); + wait_loop_output(timeleft(&timo)); + } + sigprocmask(SIG_BLOCK, &mask, NULL); + waiting = 0; calltimeout(); if (kill_link) { if (!persist) - die(0); + break; kill_link = 0; } if (get_loop_output()) break; reap_kids(); } + if (kill_link) + break; /* * Now we want to bring up the link. @@ -425,20 +445,21 @@ main(argc, argv) * 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; + sigprocmask(SIG_UNBLOCK, &mask, NULL); while ((ttyfd = open(devnam, O_NONBLOCK | O_RDWR, 0)) < 0) { if (errno != EINTR) syslog(LOG_ERR, "Failed to open %s: %m", devnam); if (!persist || errno != EINTR) goto fail; } + sigprocmask(SIG_BLOCK, &mask, NULL); if ((fdflags = fcntl(ttyfd, F_GETFL)) == -1 || fcntl(ttyfd, F_SETFL, fdflags & ~O_NONBLOCK) < 0) syslog(LOG_WARNING, "Couldn't reset non-blocking mode on device: %m"); - hungup = 0; - kill_link = 0; - /* * Do the equivalent of `mesg n' to stop broadcast messages. */ @@ -453,19 +474,24 @@ main(argc, argv) if (connector && connector[0]) { MAINDEBUG((LOG_INFO, "Connecting with <%s>", connector)); - /* set line speed, flow control, etc.; set CLOCAL for now */ - set_up_tty(ttyfd, 1); - - /* drop dtr to hang up in case modem is off hook */ if (!default_device && modem) { - setdtr(ttyfd, FALSE); + hangup_modem(ttyfd); /* in case modem is off hook */ sleep(1); - setdtr(ttyfd, TRUE); } + /* + * Set line speed, flow control, etc. + * 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, 1); + if (device_script(connector, ttyfd, ttyfd) < 0) { syslog(LOG_ERR, "Connect script failed"); - setdtr(ttyfd, FALSE); goto fail; } @@ -481,7 +507,7 @@ main(argc, argv) while ((i = open(devnam, O_RDWR)) < 0) { if (errno != EINTR) syslog(LOG_ERR, "Failed to reopen %s: %m", devnam); - if (!persist || errno != EINTR) + if (!persist || errno != EINTR || hungup || kill_link) goto fail; } close(i); @@ -500,17 +526,9 @@ main(argc, argv) syslog(LOG_INFO, "Using interface ppp%d", ifunit); (void) sprintf(ifname, "ppp%d", ifunit); - - /* write pid to file */ - (void) sprintf(pidfilename, "%s%s.pid", _PATH_VARRUN, ifname); - if ((pidfile = fopen(pidfilename, "w")) != NULL) { - fprintf(pidfile, "%d\n", pid); - (void) fclose(pidfile); - } else { - syslog(LOG_ERR, "Failed to create pid file %s: %m", - pidfilename); - pidfilename[0] = 0; - } + script_setenv("IFNAME", ifname); + + create_pidfile(); /* write pid to file */ } /* @@ -520,14 +538,21 @@ main(argc, argv) syslog(LOG_NOTICE, "Connect: %s <--> %s", ifname, devnam); lcp_lowerup(0); lcp_open(0); /* Start protocol */ + open_ccp_flag = 0; for (phase = PHASE_ESTABLISH; phase != PHASE_DEAD; ) { - wait_input(timeleft(&timo)); + if (setjmp(sigjmp) == 0) { + waiting = 1; + sigprocmask(SIG_UNBLOCK, &mask, NULL); + wait_input(timeleft(&timo)); + } + sigprocmask(SIG_BLOCK, &mask, NULL); + waiting = 0; calltimeout(); - get_input(); if (kill_link) { lcp_close(0, "User request"); kill_link = 0; } + get_input(); if (open_ccp_flag) { if (phase == PHASE_NETWORK) { ccp_fsm[0].flags = OPT_RESTART; /* clears OPT_SILENT */ @@ -585,23 +610,73 @@ main(argc, argv) phase = PHASE_HOLDOFF; TIMEOUT(holdoff_end, NULL, holdoff); do { - wait_time(timeleft(&timo)); + if (setjmp(sigjmp) == 0) { + waiting = 1; + sigprocmask(SIG_UNBLOCK, &mask, NULL); + wait_time(timeleft(&timo)); + } + sigprocmask(SIG_BLOCK, &mask, NULL); + waiting = 0; calltimeout(); if (kill_link) { - if (!persist) - die(0); kill_link = 0; phase = PHASE_DORMANT; /* allow signal to end holdoff */ } reap_kids(); } while (phase == PHASE_HOLDOFF); + if (!persist) + break; } } + /* Wait for scripts to finish */ + while (n_children > 0) + reap_kids(); + die(0); return 0; } +/* + * detach - detach us from the controlling terminal. + */ +void +detach() +{ + if (detached) + return; + if (daemon(0, 0) < 0) { + perror("Couldn't detach from controlling terminal"); + die(1); + } + detached = 1; + pid = getpid(); + /* update pid file if it has been written already */ + if (pidfilename[0]) + create_pidfile(); +} + +/* + * Create a file containing our process ID. + */ +static void +create_pidfile() +{ + FILE *pidfile; + char numbuf[16]; + + (void) sprintf(pidfilename, "%s%s.pid", _PATH_VARRUN, ifname); + if ((pidfile = fopen(pidfilename, "w")) != NULL) { + fprintf(pidfile, "%d\n", pid); + (void) fclose(pidfile); + } else { + syslog(LOG_ERR, "Failed to create pid file %s: %m", pidfilename); + pidfilename[0] = 0; + } + sprintf(numbuf, "%d", pid); + script_setenv("PPPD_PID", numbuf); +} + /* * holdoff_end - called via a timeout when the holdoff period ends. */ @@ -741,8 +816,8 @@ close_tty() disestablish_ppp(ttyfd); /* drop dtr to hang up */ - if (modem) { - setdtr(ttyfd, FALSE); + if (!default_device && modem) { + hangup_modem(ttyfd); /* * This sleep is in case the serial port has CLOCAL set by default, * and consequently will reassert DTR when we close the device. @@ -806,7 +881,7 @@ timeout(func, arg, time) for (pp = &callout; (p = *pp); pp = &p->c_next) if (newp->c_time.tv_sec < p->c_time.tv_sec || (newp->c_time.tv_sec == p->c_time.tv_sec - && newp->c_time.tv_usec < p->c_time.tv_sec)) + && newp->c_time.tv_usec < p->c_time.tv_usec)) break; newp->c_next = p; *pp = newp; @@ -922,6 +997,8 @@ hup(sig) if (conn_running) /* Send the signal to the [dis]connector process(es) also */ kill_my_pg(sig); + if (waiting) + longjmp(sigjmp, 1); } @@ -941,6 +1018,8 @@ term(sig) if (conn_running) /* Send the signal to the [dis]connector process(es) also */ kill_my_pg(sig); + if (waiting) + longjmp(sigjmp, 1); } @@ -952,7 +1031,8 @@ static void chld(sig) int sig; { - reap_kids(); + if (waiting) + longjmp(sigjmp, 1); } @@ -986,6 +1066,8 @@ open_ccp(sig) int sig; { open_ccp_flag = 1; + if (waiting) + longjmp(sigjmp, 1); } @@ -996,6 +1078,11 @@ static void bad_signal(sig) int sig; { + static int crashed = 0; + + if (crashed) + _exit(127); + crashed = 1; syslog(LOG_ERR, "Fatal signal %d", sig); if (conn_running) kill_my_pg(SIGTERM); @@ -1046,9 +1133,9 @@ device_script(program, in, out) close(out); } } - if (redirect_stderr) { + if (!nodetach && !updetach) { close(2); - errfd = open(_PATH_CONNERRS, O_WRONLY | O_APPEND | O_CREAT, 0644); + errfd = open(_PATH_CONNERRS, O_WRONLY | O_APPEND | O_CREAT, 0600); if (errfd >= 0 && errfd != 2) { dup2(errfd, 2); close(errfd); @@ -1074,25 +1161,60 @@ device_script(program, in, out) } +/* + * We maintain a list of child process pids and + * functions to call when they exit. + */ +struct subprocess { + pid_t pid; + char *prog; + void (*done) __P((void *)); + void *arg; + struct subprocess *next; +}; + +struct subprocess *children; + /* * run-program - execute a program with given arguments, * but don't wait for it. * If the program can't be executed, logs an error unless * must_exist is 0 and the program file doesn't exist. + * Returns -1 if it couldn't fork, 0 if the file doesn't exist + * or isn't an executable plain file, or the process ID of the child. + * If done != NULL, (*done)(arg) will be called later (within + * reap_kids) iff the return value is > 0. */ -int -run_program(prog, args, must_exist) +pid_t +run_program(prog, args, must_exist, done, arg) char *prog; char **args; int must_exist; + void (*done) __P((void *)); + void *arg; { int pid; - char *nullenv[1]; + struct subprocess *chp; + struct stat sbuf; + + /* + * First check if the file exists and is executable. + * We don't use access() because that would use the + * real user-id, which might not be root, and the script + * might be accessible only to root. + */ + errno = EINVAL; + if (stat(prog, &sbuf) < 0 || !S_ISREG(sbuf.st_mode) + || (sbuf.st_mode & (S_IXUSR|S_IXGRP|S_IXOTH)) == 0) { + if (must_exist || errno != ENOENT) + syslog(LOG_WARNING, "Can't execute %s: %m", prog); + return 0; + } pid = fork(); if (pid == -1) { syslog(LOG_ERR, "Failed to create child process for %s: %m", prog); - return -1; + die(1); } if (pid == 0) { int new_fd; @@ -1131,16 +1253,36 @@ run_program(prog, args, must_exist) /* SysV recommends a second fork at this point. */ - /* run the program; give it a null environment */ - nullenv[0] = NULL; - execve(prog, args, nullenv); - if (must_exist || errno != ENOENT) + /* run the program */ + execve(prog, args, script_env); + if (must_exist || errno != ENOENT) { + int i; syslog(LOG_WARNING, "Can't execute %s: %m", prog); + for (i = 0; args[i]; ++i) + syslog(LOG_DEBUG, "args[%d] = '%s'", i, args[i]); + for (i = 0; script_env[i]; ++i) + syslog(LOG_DEBUG, "env[%d] = '%s'", i, script_env[i]); + } _exit(-1); } - MAINDEBUG((LOG_DEBUG, "Script %s started; pid = %d", prog, pid)); + + if (debug) + syslog(LOG_DEBUG, "Script %s started; pid = %d", prog, pid); ++n_children; - return 0; + + chp = (struct subprocess *) malloc(sizeof(struct subprocess)); + if (chp == NULL) { + syslog(LOG_WARNING, "losing track of %s process", prog); + } else { + chp->pid = pid; + chp->prog = prog; + chp->done = done; + chp->arg = arg; + chp->next = children; + children = chp; + } + + return pid; } @@ -1152,21 +1294,28 @@ static void reap_kids() { int pid, status; + struct subprocess *chp, **prevp; if (n_children == 0) return; - if ((pid = waitpid(-1, &status, WNOHANG)) == -1) { - if (errno != ECHILD) - syslog(LOG_ERR, "Error waiting for child process: %m"); - return; - } - if (pid > 0) { + while ((pid = waitpid(-1, &status, WNOHANG)) != -1 && pid != 0) { --n_children; + for (prevp = &children; (chp = *prevp) != NULL; prevp = &chp->next) + if (chp->pid == pid) + break; + if (debug) + syslog(LOG_DEBUG, "process %d (%s) finished, status = 0x%x", + pid, (chp? chp->prog: "??"), status); if (WIFSIGNALED(status)) { - syslog(LOG_WARNING, "Child process %d terminated with signal %d", - pid, WTERMSIG(status)); + syslog(LOG_WARNING, + "Child process %s (pid %d) terminated with signal %d", + (chp? chp->prog: "??"), pid, WTERMSIG(status)); } + if (chp && chp->done) + (*chp->done)(chp->arg); } + if (pid == -1 && errno != ECHILD) + syslog(LOG_ERR, "Error waiting for child process: %m"); } @@ -1248,10 +1397,9 @@ pr_log __V((void *arg, char *fmt, ...)) fmt = va_arg(pvar, char *); #endif - vsprintf(buf, fmt, pvar); + n = vfmtmsg(buf, sizeof(buf), fmt, pvar); va_end(pvar); - n = strlen(buf); if (linep + n + 1 > line + sizeof(line)) { syslog(LOG_DEBUG, "%s", line); linep = line; @@ -1558,3 +1706,78 @@ vfmtmsg(buf, buflen, fmt, args) *buf = 0; return buf - buf0; } + +/* + * script_setenv - set an environment variable value to be used + * for scripts that we run (e.g. ip-up, auth-up, etc.) + */ +void +script_setenv(var, value) + char *var, *value; +{ + int vl = strlen(var); + int i; + char *p, *newstring; + + newstring = (char *) malloc(vl + strlen(value) + 2); + if (newstring == 0) + return; + strcpy(newstring, var); + newstring[vl] = '='; + strcpy(newstring+vl+1, value); + + /* check if this variable is already set */ + if (script_env != 0) { + for (i = 0; (p = script_env[i]) != 0; ++i) { + if (strncmp(p, var, vl) == 0 && p[vl] == '=') { + free(p); + script_env[i] = newstring; + return; + } + } + } else { + i = 0; + script_env = (char **) malloc(16 * sizeof(char *)); + if (script_env == 0) + return; + s_env_nalloc = 16; + } + + /* reallocate script_env with more space if needed */ + if (i + 1 >= s_env_nalloc) { + int new_n = i + 17; + char **newenv = (char **) realloc((void *)script_env, + new_n * sizeof(char *)); + if (newenv == 0) + return; + script_env = newenv; + s_env_nalloc = new_n; + } + + script_env[i] = newstring; + script_env[i+1] = 0; +} + +/* + * script_unsetenv - remove a variable from the environment + * for scripts. + */ +void +script_unsetenv(var) + char *var; +{ + int vl = strlen(var); + int i; + char *p; + + if (script_env == 0) + return; + for (i = 0; (p = script_env[i]) != 0; ++i) { + if (strncmp(p, var, vl) == 0 && p[vl] == '=') { + free(p); + while ((script_env[i] = script_env[i+1]) != 0) + ++i; + break; + } + } +}