1 /*        $NetBSD: tip.c,v 1.63 2020/04/23 00:35:14 joerg Exp $       */
2 
3 /*
4  * Copyright (c) 1983, 1993
5  *        The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #include <ctype.h>
34 #include <libgen.h>
35 
36 #ifndef lint
37 __COPYRIGHT("@(#) Copyright (c) 1983, 1993\
38  The Regents of the University of California.  All rights reserved.");
39 #endif /* not lint */
40 
41 #ifndef lint
42 #if 0
43 static char sccsid[] = "@(#)tip.c       8.1 (Berkeley) 6/6/93";
44 #endif
45 __RCSID("$NetBSD: tip.c,v 1.63 2020/04/23 00:35:14 joerg Exp $");
46 #endif /* not lint */
47 
48 /*
49  * tip - UNIX link to other systems
50  *  tip [-v] [-speed] system-name
51  * or
52  *  cu [options] [phone-number|"dir"]
53  */
54 #include "tip.h"
55 #include "pathnames.h"
56 
57 struct termios      term;
58 struct termios      defterm;
59 struct termios      defchars;
60 
61 FILE      *fscript;
62 
63 int       attndes[2];
64 int       fildes[2];
65 int       repdes[2];
66 int       FD;
67 #ifndef __lint__  /* not used by hayes.c, but used by some other dialers */
68 int       AC;
69 #endif /*__lint__*/
70 int       sfd;
71 int       pid;
72 uid_t     uid, euid;
73 gid_t     gid, egid;
74 int       stop;
75 int       quit;
76 int       stoprompt;
77 int       timedout;
78 int       cumode;
79 int       bits8;
80 #define STRIP_PAR   (bits8 ? 0377 : 0177)
81 
82 char      fname[80];
83 char      copyname[80];
84 char      ccc;
85 
86 int       odisc;
87 int       vflag;
88 
89 char      *DV;
90 char      *EL;
91 char      *CM;
92 char      *IE;
93 char      *OE;
94 char      *CU;
95 char      *AT;
96 char      *PN;
97 char      *DI;
98 char      *PA;
99 
100 char      *PH;
101 char      *RM;
102 char      *HO;
103 
104 long      BR;
105 long      FS;
106 
107 long      DU;
108 long      HW;
109 char      *ES;
110 char      *EX;
111 char      *FO;
112 char      *RC;
113 char      *RE;
114 char      *PR;
115 long      DL;
116 long      CL;
117 long      ET;
118 long      HD;
119 char      DC;
120 
121 __dead static void  tipusage(void);
122 
123 int       escape(void);
124 __dead static void  intprompt(int);
125 __dead static void  tipin(void);
126 
127 char      PNbuf[256];                             /* This limits the size of a number */
128 
129 static char path_phones[] = _PATH_PHONES;
130 
131 int
main(int argc,char * argv[])132 main(int argc, char *argv[])
133 {
134           char *System = NULL;
135           int c, i;
136           char *p;
137           const char *q;
138           char sbuf[12];
139           int cmdlineBR;
140           int fcarg;
141 
142           setprogname(argv[0]);
143           gid = getgid();
144           egid = getegid();
145           uid = getuid();
146           euid = geteuid();
147           if (strcmp(getprogname(), "cu") == 0) {
148                     cumode = 1;
149                     cumain(argc, argv);
150                     goto cucommon;
151           }
152 
153           if (argc > 4)
154                     tipusage();
155 
156           if (!isatty(0))
157                     errx(EXIT_FAILURE, "must be interactive");
158 
159           cmdlineBR = 0;
160           while((c = getopt(argc, argv, "v0123456789")) != -1) {
161                     switch(c) {
162 
163                     case 'v':
164                               vflag++;
165                               break;
166 
167                     case '0': case '1': case '2': case '3': case '4':
168                     case '5': case '6': case '7': case '8': case '9':
169                               cmdlineBR = cmdlineBR * 10 + (c - '0');
170                               BR = cmdlineBR;
171                               break;
172 
173                     default:
174                               warnx("%s, unknown option", argv[1]);
175                               break;
176                     }
177           }
178 
179           argc -= optind;
180           argv += optind;
181 
182           if (argc != 1)
183                     tipusage();
184           else
185                     System = argv[0];
186 
187 
188           if (System == NULL)
189                     goto notnumber;
190           if (isalpha((unsigned char)*System))
191                     goto notnumber;
192           /*
193            * System name is really a phone number...
194            * Copy the number then stomp on the original (in case the number
195            *        is private, we don't want 'ps' or 'w' to find it).
196            */
197           if (strlen(System) > sizeof PNbuf - 1) {
198                     errx(1, "phone number too long (max = %d bytes)",
199                               (int)sizeof(PNbuf) - 1);
200           }
201           (void)strlcpy(PNbuf, System, sizeof(PNbuf));
202           for (p = System; *p; p++)
203                     *p = '\0';
204           PN = PNbuf;
205           (void)snprintf(sbuf, sizeof sbuf, "tip%d", (int)BR);
206           System = sbuf;
207 
208 notnumber:
209           (void)signal(SIGINT, cleanup);
210           (void)signal(SIGQUIT, cleanup);
211           (void)signal(SIGHUP, cleanup);
212           (void)signal(SIGTERM, cleanup);
213 
214           if ((i = hunt(System)) == 0) {
215                     errx(3, "all ports busy");
216           }
217           if (i == -1) {
218                     errx(3, "link down");
219           }
220           setbuf(stdout, NULL);
221 
222           /*
223            * Kludge, their's no easy way to get the initialization
224            *   in the right order, so force it here
225            */
226           if ((PH = getenv("PHONES")) == NULL)
227                     PH = path_phones;
228           vinit();                                /* init variables */
229           setparity("none");                      /* set the parity table */
230 
231           /*
232            * Hardwired connections require the
233            *  line speed set before they make any transmissions
234            *  (this is particularly true of things like a DF03-AC)
235            */
236           if (HW) {
237                     if (ttysetup((speed_t)number(value(BAUDRATE))) != 0) {
238                               errx(3, "bad baud rate %d",
239                                   (int)number(value(BAUDRATE)));
240                     }
241           }
242           if ((q = tip_connect()) != NULL) {
243                     errx(1, "\07%s\n[EOT]", q);
244           }
245           if (!HW) {
246                     if (ttysetup((speed_t)number(value(BAUDRATE))) != 0) {
247                               errx(3, "bad baud rate %d",
248                                   (int)number(value(BAUDRATE)));
249                     }
250           }
251 
252 
253 cucommon:
254           /*
255            * From here down the code is shared with
256            * the "cu" version of tip.
257            */
258 
259           /*
260            * Direct connections with no carrier require using O_NONBLOCK on
261            * open, but we don't want to keep O_NONBLOCK after open because it
262            * will cause busy waits.
263            */
264           if (DC &&
265               ((fcarg = fcntl(FD, F_GETFL, 0)) < 0 ||
266                fcntl(FD, F_SETFL, fcarg & ~O_NONBLOCK) < 0)) {
267                     err(1, "can't clear O_NONBLOCK");
268           }
269 
270           (void)tcgetattr(0, &defterm);
271           term = defterm;
272           term.c_lflag &= ~(ICANON|IEXTEN|ECHO);
273           term.c_iflag &= ~(INPCK|ICRNL);
274           term.c_oflag &= ~OPOST;
275           term.c_cc[VMIN] = 1;
276           term.c_cc[VTIME] = 0;
277           defchars = term;
278           term.c_cc[VINTR] = term.c_cc[VQUIT] = term.c_cc[VSUSP] =
279                     term.c_cc[VDSUSP] = term.c_cc[VDISCARD] =
280                     term.c_cc[VLNEXT] = _POSIX_VDISABLE;
281           raw();
282 
283           (void)pipe(attndes);
284           (void)pipe(fildes);
285           (void)pipe(repdes);
286           (void)signal(SIGALRM, alrmtimeout);
287 
288           /*
289            * Everything's set up now:
290            *        connection established (hardwired or dialup)
291            *        line conditioned (baud rate, mode, etc.)
292            *        internal data structures (variables)
293            * so, fork one process for local side and one for remote.
294            */
295           (void)printf("%s", cumode ? "Connected\r\n" : "\07connected\r\n");
296           switch (pid = fork()) {
297           default:
298                     tipin();
299                     break;
300           case 0:
301                     tipout();
302                     break;
303           case -1:
304                     err(1, "can't fork");
305           }
306           /*NOTREACHED*/
307           exit(0);  /* XXX: pacify gcc */
308 }
309 
310 void
tipusage(void)311 tipusage(void)
312 {
313           (void)fprintf(stderr, "usage: %s [-v] [-speed] system-name\n",
314               getprogname());
315           (void)fprintf(stderr, "       %s [-v] [-speed] phone-number\n",
316               getprogname());
317           exit(1);
318 }
319 
320 void
321 /*ARGSUSED*/
cleanup(int dummy __unused)322 cleanup(int dummy __unused)
323 {
324 
325           if (odisc)
326                     (void)ioctl(0, TIOCSETD, &odisc);
327           _exit(0);
328 }
329 
330 /*
331  * put the controlling keyboard into raw mode
332  */
333 void
raw(void)334 raw(void)
335 {
336 
337           (void)tcsetattr(0, TCSADRAIN, &term);
338 }
339 
340 
341 /*
342  * return keyboard to normal mode
343  */
344 void
unraw(void)345 unraw(void)
346 {
347 
348           (void)tcsetattr(0, TCSADRAIN, &defterm);
349 }
350 
351 static    jmp_buf promptbuf;
352 
353 /*
354  * Print string ``s'', then read a string
355  *  in from the terminal.  Handles signals & allows use of
356  *  normal erase and kill characters.
357  */
358 int
prompt(const char * s,char * volatile p,size_t l)359 prompt(const char *s, char *volatile p, size_t l)
360 {
361           int c;
362           char *b = p;
363           sig_t oint, oquit;
364 
365           stoprompt = 0;
366           oint = signal(SIGINT, intprompt);
367           oquit = signal(SIGQUIT, SIG_IGN);
368           unraw();
369           (void)printf("%s", s);
370           if (setjmp(promptbuf) == 0)
371                     while ((c = getchar()) != EOF && (*p = c) != '\n' &&
372                         b + l > p)
373                               p++;
374           *p = '\0';
375 
376           raw();
377           (void)signal(SIGINT, oint);
378           (void)signal(SIGQUIT, oquit);
379           return (stoprompt || p == b);
380 }
381 
382 /*
383  * Interrupt service routine during prompting
384  */
385 static void
386 /*ARGSUSED*/
intprompt(int dummy __unused)387 intprompt(int dummy __unused)
388 {
389 
390           (void)signal(SIGINT, SIG_IGN);
391           stoprompt = 1;
392           (void)printf("\r\n");
393           longjmp(promptbuf, 1);
394 }
395 
396 /*
397  * getchar() wrapper that checks for EOF on the local end.
398  */
399 static int
xgetchar(void)400 xgetchar(void)
401 {
402           int c = getchar();
403           if (__predict_false(c == EOF)) {
404                     cleanup(SIGHUP);
405                     /* NOTREACHED */
406           }
407 
408           return c & STRIP_PAR;
409 }
410 
411 
412 /*
413  * ****TIPIN   TIPIN****
414  */
415 static void
tipin(void)416 tipin(void)
417 {
418           char gch, bol = 1;
419 
420           /*
421            * Kinda klugey here...
422            *   check for scripting being turned on from the .tiprc file,
423            *   but be careful about just using setscript(), as we may
424            *   send a SIGEMT before tipout has a chance to set up catching
425            *   it; so wait a second, then setscript()
426            */
427           if (boolean(value(SCRIPT))) {
428                     (void)sleep(1);
429                     setscript();
430           }
431 
432           for (;;) {
433                     gch = xgetchar();
434                     if ((gch == character(value(ESCAPE))) && bol) {
435                               if (!(gch = escape()))
436                                         continue;
437                     } else if (!cumode &&
438                         gch && gch == character(value(RAISECHAR))) {
439                               setboolean(value(RAISE), !boolean(value(RAISE)));
440                               continue;
441                     } else if (gch == '\r' || gch == '\n') {
442                               bol = 1;
443                               xpwrite(FD, &gch, 1);
444                               if (boolean(value(HALFDUPLEX)))
445                                         (void)printf("%s\n", gch == '\r' ? "\r" : "");
446                               continue;
447                     } else if (!cumode && gch && gch == character(value(FORCE)))
448                               gch = xgetchar();
449                     bol = any(gch, value(EOL));
450                     if (boolean(value(RAISE)) && islower((unsigned char)gch))
451                               gch = toupper((unsigned char)gch);
452                     xpwrite(FD, &gch, 1);
453                     if (boolean(value(HALFDUPLEX)))
454                               (void)printf("%c", gch);
455           }
456 }
457 
458 /*
459  * Escape handler --
460  *  called on recognition of ``escapec'' at the beginning of a line
461  */
462 int
escape(void)463 escape(void)
464 {
465           char gch;
466           esctable_t *p;
467           char c = character(value(ESCAPE));
468 
469           gch = xgetchar();
470           for (p = etable; p->e_char; p++)
471                     if (p->e_char == gch) {
472                               if ((p->e_flags&PRIV) && uid)
473                                         continue;
474                               (void)printf("%s", ctrl(c));
475                               (*p->e_func)(gch);
476                               return (0);
477                     }
478           /* ESCAPE ESCAPE forces ESCAPE */
479           if (c != gch)
480                     xpwrite(FD, &c, 1);
481           return (gch);
482 }
483 
484 int
any(char c,const char * p)485 any(char c, const char *p)
486 {
487 
488           while (p && *p)
489                     if (*p++ == c)
490                               return (1);
491           return (0);
492 }
493 
494 char *
interp(const char * s)495 interp(const char *s)
496 {
497           static char buf[256];
498           char *p = buf, c;
499           const char *q;
500 
501           while ((c = *s++) != 0 && buf + sizeof buf - p > 2) {
502                     for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++)
503                               if (*q++ == c) {
504                                         *p++ = '\\'; *p++ = *q;
505                                         goto next;
506                               }
507                     if (c < 040) {
508                               *p++ = '^'; *p++ = c + 'A'-1;
509                     } else if (c == 0177) {
510                               *p++ = '^'; *p++ = '?';
511                     } else
512                               *p++ = c;
513           next:
514                     ;
515           }
516           *p = '\0';
517           return (buf);
518 }
519 
520 char *
ctrl(char c)521 ctrl(char c)
522 {
523           static char s[3];
524 
525           if (c < 040 || c == 0177) {
526                     s[0] = '^';
527                     s[1] = c == 0177 ? '?' : c+'A'-1;
528                     s[2] = '\0';
529           } else {
530                     s[0] = c;
531                     s[1] = '\0';
532           }
533           return (s);
534 }
535 
536 /*
537  * Help command
538  */
539 void
help(char c)540 help(char c)
541 {
542           esctable_t *p;
543 
544           (void)printf("%c\r\n", c);
545           for (p = etable; p->e_char; p++) {
546                     if ((p->e_flags&PRIV) && uid)
547                               continue;
548                     (void)printf("%2s", ctrl(character(value(ESCAPE))));
549                     (void)printf("%-2s %c   %s\r\n", ctrl(p->e_char),
550                               p->e_flags&EXP ? '*': ' ', p->e_help);
551           }
552 }
553 
554 /*
555  * Set up the "remote" tty's state
556  */
557 int
ttysetup(speed_t spd)558 ttysetup(speed_t spd)
559 {
560           struct termios      cntrl;
561 
562           (void)tcgetattr(FD, &cntrl);
563           (void)cfsetospeed(&cntrl, spd);
564           (void)cfsetispeed(&cntrl, spd);
565           cntrl.c_cflag &= ~(CSIZE|PARENB);
566           cntrl.c_cflag |= CS8;
567           if (DC)
568                     cntrl.c_cflag |= CLOCAL;
569           if (boolean(value(HARDWAREFLOW)))
570                     cntrl.c_cflag |= CRTSCTS;
571           cntrl.c_iflag &= ~(ISTRIP|ICRNL);
572           cntrl.c_oflag &= ~OPOST;
573           cntrl.c_lflag &= ~(ICANON|ISIG|IEXTEN|ECHO);
574           cntrl.c_cc[VMIN] = 1;
575           cntrl.c_cc[VTIME] = 0;
576           if (boolean(value(TAND)))
577                     cntrl.c_iflag |= IXOFF|IXON;
578           else
579                     cntrl.c_iflag &= ~(IXOFF|IXON);
580           return tcsetattr(FD, TCSAFLUSH, &cntrl);
581 }
582 
583 static char partab[0200];
584 
585 /*
586  * Do a write to the remote machine with the correct parity.
587  * We are doing 8 bit wide output, so we just generate a character
588  * with the right parity and output it.
589  */
590 void
xpwrite(int fd,char * buf,size_t n)591 xpwrite(int fd, char *buf, size_t n)
592 {
593           size_t i;
594           char *bp;
595 
596           bp = buf;
597           if (bits8 == 0)
598                     for (i = 0; i < n; i++) {
599                               *bp = partab[(*bp) & 0177];
600                               bp++;
601                     }
602           if (write(fd, buf, n) < 0) {
603                     if (errno == EIO)
604                               tipabort("Lost carrier.");
605                     /* this is questionable */
606                     warn("write");
607           }
608 }
609 
610 /*
611  * Build a parity table with appropriate high-order bit.
612  */
613 void
setparity(const char * defparity)614 setparity(const char *defparity)
615 {
616           int i, flip, clr, set;
617           const char *parity;
618           static char *curpar;
619 
620           if (value(PARITY) == NULL || ((char *)value(PARITY))[0] == '\0') {
621                     if (curpar != NULL)
622                               free(curpar);
623                     value(PARITY) = curpar = strdup(defparity);
624           }
625           parity = value(PARITY);
626           if (strcmp(parity, "none") == 0) {
627                     bits8 = 1;
628                     return;
629           }
630           bits8 = 0;
631           flip = 0;
632           clr = 0377;
633           set = 0;
634           if (strcmp(parity, "odd") == 0)
635                     flip = 0200;                            /* reverse bit 7 */
636           else if (strcmp(parity, "zero") == 0)
637                     clr = 0177;                             /* turn off bit 7 */
638           else if (strcmp(parity, "one") == 0)
639                     set = 0200;                             /* turn on bit 7 */
640           else if (strcmp(parity, "even") != 0) {
641                     (void)fprintf(stderr, "%s: unknown parity value\r\n", parity);
642                     (void)fflush(stderr);
643           }
644           for (i = 0; i < 0200; i++)
645                     partab[i] = ((evenpartab[i] ^ flip) | set) & clr;
646 }
647