1/*-
2 * Copyright (c) 1997 Brian Somers <brian@Awfulhak.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD$");
29
30#include <sys/types.h>
31
32#include <sys/socket.h>
33#include <netinet/in.h>
34#include <arpa/inet.h>
35#include <sys/un.h>
36#include <netdb.h>
37
38#include <sys/time.h>
39#include <err.h>
40#include <errno.h>
41#include <histedit.h>
42#include <semaphore.h>
43#include <pthread.h>
44#include <setjmp.h>
45#include <signal.h>
46#include <stdio.h>
47#include <stdlib.h>
48#include <string.h>
49#include <time.h>
50#include <unistd.h>
51
52#define LINELEN 2048
53
54/* Data passed to the threads we create */
55struct thread_data {
56    EditLine *edit;		/* libedit stuff */
57    History *hist;		/* libedit stuff */
58    pthread_t trm;		/* Terminal thread (for pthread_kill()) */
59    int ppp;			/* ppp descriptor */
60};
61
62/* Flags passed to Receive() */
63#define REC_PASSWD  (1)		/* Handle a password request from ppp */
64#define REC_SHOW    (2)		/* Show everything except prompts */
65#define REC_VERBOSE (4)		/* Show everything */
66
67static char *passwd;
68static char *prompt;		/* Tell libedit what the current prompt is */
69static int data = -1;		/* setjmp() has been done when data != -1 */
70static jmp_buf pppdead;		/* Jump the Terminal thread out of el_gets() */
71static int timetogo;		/* Tell the Monitor thread to exit */
72static sem_t sem_select;	/* select() co-ordination between threads */
73static int TimedOut;		/* Set if our connect() timed out */
74static int want_sem_post;	/* Need to let the Monitor thread in ? */
75
76/*
77 * How to use pppctl...
78 */
79static int
80usage()
81{
82    fprintf(stderr, "usage: pppctl [-v] [-t n] [-p passwd] "
83            "Port|LocalSock [command[;command]...]\n");
84    fprintf(stderr, "              -v tells pppctl to output all"
85            " conversation\n");
86    fprintf(stderr, "              -t n specifies a timeout of n"
87            " seconds when connecting (default 2)\n");
88    fprintf(stderr, "              -p passwd specifies your password\n");
89    exit(1);
90}
91
92/*
93 * Handle the SIGALRM received due to a connect() timeout.
94 */
95static void
96Timeout(int Sig)
97{
98    TimedOut = 1;
99}
100
101/*
102 * A callback routine for libedit to find out what the current prompt is.
103 * All the work is done in Receive() below.
104 */
105static char *
106GetPrompt(EditLine *e)
107{
108    if (prompt == NULL)
109        prompt = "";
110    return prompt;
111}
112
113/*
114 * Receive data from the ppp descriptor.
115 * We also handle password prompts here (if asked via the `display' arg)
116 * and buffer what our prompt looks like (via the `prompt' global).
117 */
118static int
119Receive(int fd, int display)
120{
121    static char Buffer[LINELEN];
122    struct timeval t;
123    int Result;
124    char *last;
125    fd_set f;
126    int len;
127    int err;
128
129    FD_ZERO(&f);
130    FD_SET(fd, &f);
131    t.tv_sec = 0;
132    t.tv_usec = 100000;
133    prompt = Buffer;
134    len = 0;
135
136    while (Result = read(fd, Buffer+len, sizeof(Buffer)-len-1), Result != -1) {
137        if (Result == 0) {
138            Result = -1;
139            break;
140        }
141        len += Result;
142        Buffer[len] = '\0';
143        if (len > 2 && !strcmp(Buffer+len-2, "> ")) {
144            prompt = strrchr(Buffer, '\n');
145            if (display & (REC_SHOW|REC_VERBOSE)) {
146                if (display & REC_VERBOSE)
147                    last = Buffer+len-1;
148                else
149                    last = prompt;
150                if (last) {
151                    last++;
152                    write(STDOUT_FILENO, Buffer, last-Buffer);
153                }
154            }
155            prompt = prompt == NULL ? Buffer : prompt+1;
156            for (last = Buffer+len-2; last > Buffer && *last != ' '; last--)
157                ;
158            if (last > Buffer+3 && !strncmp(last-3, " on", 3)) {
159                 /* a password is required ! */
160                 if (display & REC_PASSWD) {
161                    /* password time */
162                    if (!passwd)
163                        passwd = getpass("Password: ");
164                    sprintf(Buffer, "passwd %s\n", passwd);
165                    memset(passwd, '\0', strlen(passwd));
166                    if (display & REC_VERBOSE)
167                        write(STDOUT_FILENO, Buffer, strlen(Buffer));
168                    write(fd, Buffer, strlen(Buffer));
169                    memset(Buffer, '\0', strlen(Buffer));
170                    return Receive(fd, display & ~REC_PASSWD);
171                }
172                Result = 1;
173            } else
174                Result = 0;
175            break;
176        } else
177            prompt = "";
178        if (len == sizeof Buffer - 1) {
179            int flush;
180            if ((last = strrchr(Buffer, '\n')) == NULL)
181                /* Yeuch - this is one mother of a line ! */
182                flush = sizeof Buffer / 2;
183            else
184                flush = last - Buffer + 1;
185            write(STDOUT_FILENO, Buffer, flush);
186            strcpy(Buffer, Buffer + flush);
187            len -= flush;
188        }
189        if ((Result = select(fd + 1, &f, NULL, NULL, &t)) <= 0) {
190            err = Result == -1 ? errno : 0;
191            if (len)
192                write(STDOUT_FILENO, Buffer, len);
193            if (err == EINTR)
194                continue;
195            break;
196        }
197    }
198
199    return Result;
200}
201
202/*
203 * Handle being told by the Monitor thread that there's data to be read
204 * on the ppp descriptor.
205 *
206 * Note, this is a signal handler - be careful of what we do !
207 */
208static void
209InputHandler(int sig)
210{
211    static char buf[LINELEN];
212    struct timeval t;
213    int len;
214    fd_set f;
215
216    if (data != -1) {
217        FD_ZERO(&f);
218        FD_SET(data, &f);
219        t.tv_sec = t.tv_usec = 0;
220
221        if (select(data + 1, &f, NULL, NULL, &t) > 0) {
222            len = read(data, buf, sizeof buf);
223
224            if (len > 0)
225                write(STDOUT_FILENO, buf, len);
226            else if (data != -1)
227                longjmp(pppdead, -1);
228        }
229
230        sem_post(&sem_select);
231    } else
232        /* Don't let the Monitor thread in 'till we've set ``data'' up again */
233        want_sem_post = 1;
234}
235
236/*
237 * This is a simple wrapper for el_gets(), allowing our SIGUSR1 signal
238 * handler (above) to take effect only after we've done a setjmp().
239 *
240 * We don't want it to do anything outside of here as we're going to
241 * service the ppp descriptor anyway.
242 */
243static const char *
244SmartGets(EditLine *e, int *count, int fd)
245{
246    const char *result;
247
248    if (setjmp(pppdead))
249        result = NULL;
250    else {
251        data = fd;
252        if (want_sem_post)
253            /* Let the Monitor thread in again */
254            sem_post(&sem_select);
255        result = el_gets(e, count);
256    }
257
258    data = -1;
259
260    return result;
261}
262
263/*
264 * The Terminal thread entry point.
265 *
266 * The bulk of the interactive work is done here.  We read the terminal,
267 * write the results to our ppp descriptor and read the results back.
268 *
269 * While reading the terminal (using el_gets()), it's possible to take
270 * a SIGUSR1 from the Monitor thread, telling us that the ppp descriptor
271 * has some data.  The data is read and displayed by the signal handler
272 * itself.
273 */
274static void *
275Terminal(void *v)
276{
277    struct sigaction act, oact;
278    struct thread_data *td;
279    const char *l;
280    int len;
281#ifndef __OpenBSD__
282    HistEvent hev = { 0, "" };
283#endif
284
285    act.sa_handler = InputHandler;
286    sigemptyset(&act.sa_mask);
287    act.sa_flags = SA_RESTART;
288    sigaction(SIGUSR1, &act, &oact);
289
290    td = (struct thread_data *)v;
291    want_sem_post = 1;
292
293    while ((l = SmartGets(td->edit, &len, td->ppp))) {
294        if (len > 1)
295#ifdef __OpenBSD__
296            history(td->hist, H_ENTER, l);
297#else
298            history(td->hist, &hev, H_ENTER, l);
299#endif
300        write(td->ppp, l, len);
301        if (Receive(td->ppp, REC_SHOW) != 0)
302            break;
303    }
304
305    return NULL;
306}
307
308/*
309 * The Monitor thread entry point.
310 *
311 * This thread simply monitors our ppp descriptor.  When there's something
312 * to read, a SIGUSR1 is sent to the Terminal thread.
313 *
314 * sem_select() is used by the Terminal thread to keep us from sending
315 * flurries of SIGUSR1s, and is used from the main thread to wake us up
316 * when it's time to exit.
317 */
318static void *
319Monitor(void *v)
320{
321    struct thread_data *td;
322    fd_set f;
323    int ret;
324
325    td = (struct thread_data *)v;
326    FD_ZERO(&f);
327    FD_SET(td->ppp, &f);
328
329    sem_wait(&sem_select);
330    while (!timetogo)
331        if ((ret = select(td->ppp + 1, &f, NULL, NULL, NULL)) > 0) {
332            pthread_kill(td->trm, SIGUSR1);
333            sem_wait(&sem_select);
334        }
335
336    return NULL;
337}
338
339static const char *
340sockaddr_ntop(const struct sockaddr *sa)
341{
342    const void *addr;
343    static char addrbuf[INET6_ADDRSTRLEN];
344
345    switch (sa->sa_family) {
346    case AF_INET:
347	addr = &((const struct sockaddr_in *)sa)->sin_addr;
348	break;
349    case AF_UNIX:
350	addr = &((const struct sockaddr_un *)sa)->sun_path;
351	break;
352    case AF_INET6:
353	addr = &((const struct sockaddr_in6 *)sa)->sin6_addr;
354	break;
355    default:
356	return NULL;
357    }
358    inet_ntop(sa->sa_family, addr, addrbuf, sizeof(addrbuf));
359    return addrbuf;
360}
361
362/*
363 * Connect to ppp using either a local domain socket or a tcp socket.
364 *
365 * If we're given arguments, process them and quit, otherwise create two
366 * threads to handle interactive mode.
367 */
368int
369main(int argc, char **argv)
370{
371    struct sockaddr_un ifsun;
372    int n, arg, fd, len, verbose, save_errno, hide1, hide1off, hide2;
373    unsigned TimeoutVal;
374    char *DoneWord = "x", *next, *start;
375    struct sigaction act, oact;
376    void *thread_ret;
377    pthread_t mon;
378    char Command[LINELEN];
379    char Buffer[LINELEN];
380
381    verbose = 0;
382    TimeoutVal = 2;
383    hide1 = hide1off = hide2 = 0;
384
385    for (arg = 1; arg < argc; arg++)
386        if (*argv[arg] == '-') {
387            for (start = argv[arg] + 1; *start; start++)
388                switch (*start) {
389                    case 't':
390                        TimeoutVal = (unsigned)atoi
391                            (start[1] ? start + 1 : argv[++arg]);
392                        start = DoneWord;
393                        break;
394
395                    case 'v':
396                        verbose = REC_VERBOSE;
397                        break;
398
399                    case 'p':
400                        if (start[1]) {
401                          hide1 = arg;
402                          hide1off = start - argv[arg];
403                          passwd = start + 1;
404                        } else {
405                          hide1 = arg;
406                          hide1off = start - argv[arg];
407                          passwd = argv[++arg];
408                          hide2 = arg;
409                        }
410                        start = DoneWord;
411                        break;
412
413                    default:
414                        usage();
415                }
416        }
417        else
418            break;
419
420
421    if (argc < arg + 1)
422        usage();
423
424    if (hide1) {
425      char title[1024];
426      int pos, harg;
427
428      for (harg = pos = 0; harg < argc; harg++)
429        if (harg == 0 || harg != hide2) {
430          if (harg == 0 || harg != hide1)
431            n = snprintf(title + pos, sizeof title - pos, "%s%s",
432                            harg ? " " : "", argv[harg]);
433          else if (hide1off > 1)
434            n = snprintf(title + pos, sizeof title - pos, " %.*s",
435                            hide1off, argv[harg]);
436          else
437            n = 0;
438          if (n < 0 || n >= sizeof title - pos)
439            break;
440          pos += n;
441        }
442#ifdef __FreeBSD__
443      setproctitle("-%s", title);
444#else
445      setproctitle("%s", title);
446#endif
447    }
448
449    if (*argv[arg] == '/') {
450        memset(&ifsun, '\0', sizeof ifsun);
451        ifsun.sun_len = strlen(argv[arg]);
452        if (ifsun.sun_len > sizeof ifsun.sun_path - 1) {
453            warnx("%s: path too long", argv[arg]);
454            return 1;
455        }
456        ifsun.sun_family = AF_LOCAL;
457        strcpy(ifsun.sun_path, argv[arg]);
458
459        if (fd = socket(AF_LOCAL, SOCK_STREAM, 0), fd < 0) {
460            warnx("cannot create local domain socket");
461            return 2;
462        }
463	if (connect(fd, (struct sockaddr *)&ifsun, sizeof(ifsun)) < 0) {
464	    if (errno)
465		warn("cannot connect to socket %s", argv[arg]);
466	    else
467		warnx("cannot connect to socket %s", argv[arg]);
468	    close(fd);
469	    return 3;
470	}
471    } else {
472        char *addr, *p, *port;
473	const char *caddr;
474	struct addrinfo hints, *res, *pai;
475        int gai;
476	char local[] = "localhost";
477
478	addr = argv[arg];
479	if (addr[strspn(addr, "0123456789")] == '\0') {
480	    /* port on local machine */
481	    port = addr;
482	    addr = local;
483	} else if (*addr == '[') {
484	    /* [addr]:port */
485	    if ((p = strchr(addr, ']')) == NULL) {
486		warnx("%s: mismatched '['", addr);
487		return 1;
488	    }
489	    addr++;
490	    *p++ = '\0';
491	    if (*p != ':') {
492		warnx("%s: missing port", addr);
493		return 1;
494	    }
495	    port = ++p;
496	} else {
497	    /* addr:port */
498	    p = addr + strcspn(addr, ":");
499	    if (*p != ':') {
500		warnx("%s: missing port", addr);
501		return 1;
502	    }
503	    *p++ = '\0';
504	    port = p;
505	}
506	memset(&hints, 0, sizeof(hints));
507	hints.ai_socktype = SOCK_STREAM;
508	gai = getaddrinfo(addr, port, &hints, &res);
509	if (gai != 0) {
510	    warnx("%s: %s", addr, gai_strerror(gai));
511	    return 1;
512	}
513	for (pai = res; pai != NULL; pai = pai->ai_next) {
514	    if (fd = socket(pai->ai_family, pai->ai_socktype,
515		pai->ai_protocol), fd < 0) {
516		warnx("cannot create socket");
517		continue;
518	    }
519	    TimedOut = 0;
520	    if (TimeoutVal) {
521		act.sa_handler = Timeout;
522		sigemptyset(&act.sa_mask);
523		act.sa_flags = 0;
524		sigaction(SIGALRM, &act, &oact);
525		alarm(TimeoutVal);
526	    }
527	    if (connect(fd, pai->ai_addr, pai->ai_addrlen) == 0)
528		break;
529	    if (TimeoutVal) {
530		save_errno = errno;
531		alarm(0);
532		sigaction(SIGALRM, &oact, 0);
533		errno = save_errno;
534	    }
535	    caddr = sockaddr_ntop(pai->ai_addr);
536	    if (caddr == NULL)
537		caddr = argv[arg];
538	    if (TimedOut)
539		warnx("timeout: cannot connect to %s", caddr);
540	    else {
541		if (errno)
542		    warn("cannot connect to %s", caddr);
543		else
544		    warnx("cannot connect to %s", caddr);
545	    }
546	    close(fd);
547	}
548	freeaddrinfo(res);
549	if (pai == NULL)
550	    return 1;
551	if (TimeoutVal) {
552	    alarm(0);
553	    sigaction(SIGALRM, &oact, 0);
554	}
555    }
556
557    len = 0;
558    Command[sizeof(Command)-1] = '\0';
559    for (arg++; arg < argc; arg++) {
560        if (len && len < sizeof(Command)-1)
561            strcpy(Command+len++, " ");
562        strncpy(Command+len, argv[arg], sizeof(Command)-len-1);
563        len += strlen(Command+len);
564    }
565
566    switch (Receive(fd, verbose | REC_PASSWD)) {
567        case 1:
568            fprintf(stderr, "Password incorrect\n");
569            break;
570
571        case 0:
572            passwd = NULL;
573            if (len == 0) {
574                struct thread_data td;
575                const char *env;
576                int size;
577#ifndef __OpenBSD__
578                HistEvent hev = { 0, "" };
579#endif
580
581                td.hist = history_init();
582                if ((env = getenv("EL_SIZE"))) {
583                    size = atoi(env);
584                    if (size < 0)
585                      size = 20;
586                } else
587                    size = 20;
588#ifdef __OpenBSD__
589                history(td.hist, H_EVENT, size);
590                td.edit = el_init("pppctl", stdin, stdout);
591#else
592                history(td.hist, &hev, H_SETSIZE, size);
593                td.edit = el_init("pppctl", stdin, stdout, stderr);
594#endif
595                el_source(td.edit, NULL);
596                el_set(td.edit, EL_PROMPT, GetPrompt);
597                if ((env = getenv("EL_EDITOR"))) {
598                    if (!strcmp(env, "vi"))
599                        el_set(td.edit, EL_EDITOR, "vi");
600                    else if (!strcmp(env, "emacs"))
601                        el_set(td.edit, EL_EDITOR, "emacs");
602                }
603                el_set(td.edit, EL_SIGNAL, 1);
604                el_set(td.edit, EL_HIST, history, (const char *)td.hist);
605
606                td.ppp = fd;
607                td.trm = NULL;
608
609                /*
610                 * We create two threads.  The Terminal thread does all the
611                 * work while the Monitor thread simply tells the Terminal
612                 * thread when ``fd'' becomes readable.  The telling is done
613                 * by sending a SIGUSR1 to the Terminal thread.  The
614                 * sem_select semaphore is used to prevent the monitor
615                 * thread from firing excessive signals at the Terminal
616                 * thread (it's abused for exit handling too - see below).
617                 *
618                 * The Terminal thread never uses td.trm !
619                 */
620                sem_init(&sem_select, 0, 0);
621
622                pthread_create(&td.trm, NULL, Terminal, &td);
623                pthread_create(&mon, NULL, Monitor, &td);
624
625                /* Wait for the terminal thread to finish */
626                pthread_join(td.trm, &thread_ret);
627                fprintf(stderr, "Connection closed\n");
628
629                /* Get rid of the monitor thread by abusing sem_select */
630                timetogo = 1;
631                close(fd);
632                fd = -1;
633                sem_post(&sem_select);
634                pthread_join(mon, &thread_ret);
635
636                /* Restore our terminal and release resources */
637                el_end(td.edit);
638                history_end(td.hist);
639                sem_destroy(&sem_select);
640            } else {
641                start = Command;
642                do {
643                    next = strchr(start, ';');
644                    while (*start == ' ' || *start == '\t')
645                        start++;
646                    if (next)
647                        *next = '\0';
648                    strcpy(Buffer, start);
649                    Buffer[sizeof(Buffer)-2] = '\0';
650                    strcat(Buffer, "\n");
651                    if (verbose)
652                        write(STDOUT_FILENO, Buffer, strlen(Buffer));
653                    write(fd, Buffer, strlen(Buffer));
654                    if (Receive(fd, verbose | REC_SHOW) != 0) {
655                        fprintf(stderr, "Connection closed\n");
656                        break;
657                    }
658                    if (next)
659                        start = ++next;
660                } while (next && *next);
661                if (verbose)
662                    write(STDOUT_FILENO, "quit\n", 5);
663                write(fd, "quit\n", 5);
664                while (Receive(fd, verbose | REC_SHOW) == 0)
665                    ;
666                if (verbose)
667                    puts("");
668            }
669            break;
670
671        default:
672            warnx("ppp is not responding");
673            break;
674    }
675
676    if (fd != -1)
677        close(fd);
678
679    return 0;
680}
681