xref: /freebsd/usr.sbin/ppp/prompt.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57) 
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 1998 Brian Somers <brian@Awfulhak.org>
5  * 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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 #include <sys/param.h>
32 #include <netinet/in.h>
33 #include <netinet/in_systm.h>
34 #include <netinet/ip.h>
35 #include <sys/socket.h>
36 #include <sys/un.h>
37 
38 #include <errno.h>
39 #include <stdarg.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <sys/fcntl.h>
44 #include <termios.h>
45 #include <unistd.h>
46 
47 #include "layer.h"
48 #include "defs.h"
49 #include "timer.h"
50 #include "command.h"
51 #include "log.h"
52 #include "descriptor.h"
53 #include "prompt.h"
54 #include "fsm.h"
55 #include "auth.h"
56 #include "iplist.h"
57 #include "throughput.h"
58 #include "slcompress.h"
59 #include "mbuf.h"
60 #include "lqr.h"
61 #include "hdlc.h"
62 #include "lcp.h"
63 #include "ncpaddr.h"
64 #include "ipcp.h"
65 #include "filter.h"
66 #include "async.h"
67 #include "ccp.h"
68 #include "link.h"
69 #include "physical.h"
70 #include "mp.h"
71 #ifndef NORADIUS
72 #include "radius.h"
73 #endif
74 #include "ipv6cp.h"
75 #include "ncp.h"
76 #include "bundle.h"
77 #include "chat.h"
78 #include "chap.h"
79 #include "cbcp.h"
80 #include "datalink.h"
81 #include "server.h"
82 #include "main.h"
83 
84 static void
85 prompt_Display(struct prompt *p)
86 {
87   /* XXX: See Index2Nam() - should we only figure this out once ? */
88   static char shostname[MAXHOSTNAMELEN];
89   const char *pconnect, *pauth;
90 
91   if (p->TermMode || !p->needprompt)
92     return;
93 
94   p->needprompt = 0;
95 
96   if (p->nonewline)
97     p->nonewline = 0;
98   else
99     fprintf(p->Term, "\n");
100 
101   if (p->auth == LOCAL_AUTH)
102     pauth = " ON ";
103   else
104     pauth = " on ";
105 
106   if (p->bundle->ncp.ipcp.fsm.state == ST_OPENED)
107     pconnect = "PPP";
108 #ifndef NOINET6
109   else if (!Enabled(p->bundle, OPT_IPCP) &&
110 	   p->bundle->ncp.ipv6cp.fsm.state == ST_OPENED)
111     pconnect = "PPP";
112 #endif
113   else if (bundle_Phase(p->bundle) == PHASE_NETWORK)
114     pconnect = "PPp";
115   else if (bundle_Phase(p->bundle) == PHASE_AUTHENTICATE)
116     pconnect = "Ppp";
117   else
118     pconnect = "ppp";
119 
120   if (*shostname == '\0') {
121     char *dot;
122 
123     if (gethostname(shostname, sizeof shostname) || *shostname == '\0')
124       strcpy(shostname, "localhost");
125     else if ((dot = strchr(shostname, '.')))
126       *dot = '\0';
127   }
128 
129   fprintf(p->Term, "%s%s%s> ", pconnect, pauth, shostname);
130   fflush(p->Term);
131 }
132 
133 static int
134 prompt_UpdateSet(struct fdescriptor *d, fd_set *r, fd_set *w __unused,
135 		 fd_set *e, int *n)
136 {
137   struct prompt *p = descriptor2prompt(d);
138   int sets;
139 
140   sets = 0;
141 
142   if (!p->active)
143     return sets;
144 
145   if (p->fd_in >= 0) {
146     if (r) {
147       FD_SET(p->fd_in, r);
148       log_Printf(LogTIMER, "prompt %s: fdset(r) %d\n", p->src.from, p->fd_in);
149       sets++;
150     }
151     if (e) {
152       FD_SET(p->fd_in, e);
153       log_Printf(LogTIMER, "prompt %s: fdset(e) %d\n", p->src.from, p->fd_in);
154       sets++;
155     }
156     if (sets && *n < p->fd_in + 1)
157       *n = p->fd_in + 1;
158   }
159 
160   prompt_Display(p);
161 
162   return sets;
163 }
164 
165 static int
166 prompt_IsSet(struct fdescriptor *d, const fd_set *fdset)
167 {
168   struct prompt *p = descriptor2prompt(d);
169   return p->fd_in >= 0 && FD_ISSET(p->fd_in, fdset);
170 }
171 
172 
173 static void
174 prompt_ShowHelp(struct prompt *p)
175 {
176   prompt_Printf(p, "The following commands are available:\n");
177   prompt_Printf(p, " ~p\tEnter Packet mode\n");
178   prompt_Printf(p, " ~t\tShow timers\n");
179   prompt_Printf(p, " ~m\tShow memory map\n");
180   prompt_Printf(p, " ~.\tTerminate program\n");
181   prompt_Printf(p, " ~?\tThis help\n");
182 }
183 
184 static void
185 prompt_Read(struct fdescriptor *d, struct bundle *bundle,
186 	    const fd_set *fdset __unused)
187 {
188   struct prompt *p = descriptor2prompt(d);
189   struct prompt *op;
190   int n;
191   char ch;
192   char linebuff[LINE_LEN];
193 
194   if (p->TermMode == NULL) {
195     n = read(p->fd_in, linebuff, sizeof linebuff - 1);
196     if (n > 0) {
197       if (linebuff[n-1] == '\n')
198         linebuff[--n] = '\0';
199       else
200         linebuff[n] = '\0';
201       p->nonewline = 1;		/* Maybe command_Decode does a prompt */
202       prompt_Required(p);
203       if (n) {
204         if ((op = log_PromptContext) == NULL)
205           log_PromptContext = p;
206         if (!command_Decode(bundle, linebuff, n, p, p->src.from))
207           prompt_Printf(p, "Syntax error\n");
208         log_PromptContext = op;
209       }
210     } else if (n <= 0) {
211       log_Printf(LogPHASE, "%s: Client connection closed.\n", p->src.from);
212       if (!p->owner)
213         Cleanup();
214       prompt_Destroy(p, 0);
215     }
216     return;
217   }
218 
219   switch (p->TermMode->state) {
220     case DATALINK_CLOSED:
221       prompt_Printf(p, "Link lost, terminal mode.\n");
222       prompt_TtyCommandMode(p);
223       p->nonewline = 0;
224       prompt_Required(p);
225       return;
226 
227     case DATALINK_READY:
228       break;
229 
230     case DATALINK_OPEN:
231       prompt_Printf(p, "\nPacket mode detected.\n");
232       prompt_TtyCommandMode(p);
233       p->nonewline = 0;
234       /* We'll get a prompt because of our status change */
235       /* FALLTHROUGH */
236 
237     default:
238       /* Wait 'till we're in a state we care about */
239       return;
240   }
241 
242   /*
243    * We are in terminal mode, decode special sequences
244    */
245   n = read(p->fd_in, &ch, 1);
246   log_Printf(LogDEBUG, "Got %d bytes (reading from the terminal)\n", n);
247 
248   if (n > 0) {
249     switch (p->readtilde) {
250     case 0:
251       if (ch == '~')
252         p->readtilde = 1;
253       else
254 	if (physical_Write(p->TermMode->physical, &ch, n) < 0) {
255 	  log_Printf(LogWARN, "error writing to modem: %s\n", strerror(errno));
256           prompt_TtyCommandMode(p);
257         }
258       break;
259     case 1:
260       switch (ch) {
261       case '?':
262 	prompt_ShowHelp(p);
263 	break;
264       case 'p':
265         datalink_Up(p->TermMode, 0, 1);
266         prompt_Printf(p, "\nPacket mode.\n");
267 	prompt_TtyCommandMode(p);
268         break;
269       case '.':
270 	prompt_TtyCommandMode(p);
271         p->nonewline = 0;
272         prompt_Required(p);
273 	break;
274       case 't':
275 	timer_Show(0, p);
276 	break;
277       case 'm':
278         {
279           struct cmdargs arg;
280 
281           arg.cmdtab = NULL;
282           arg.cmd = NULL;
283           arg.argc = 0;
284           arg.argn = 0;
285           arg.argv = NULL;
286           arg.bundle = bundle;
287           arg.cx = p->TermMode;
288           arg.prompt = p;
289 
290 	  mbuf_Show(&arg);
291         }
292 	break;
293       default:
294 	if (physical_Write(p->TermMode->physical, &ch, n) < 0) {
295 	  log_Printf(LogWARN, "error writing to modem: %s\n", strerror(errno));
296           prompt_TtyCommandMode(p);
297         }
298 	break;
299       }
300       p->readtilde = 0;
301       break;
302     }
303   }
304 }
305 
306 static int
307 prompt_Write(struct fdescriptor *d __unused, struct bundle *bundle __unused,
308 	     const fd_set *fdset __unused)
309 {
310   /* We never want to write here ! */
311   log_Printf(LogALERT, "prompt_Write: Internal error: Bad call !\n");
312   return 0;
313 }
314 
315 struct prompt *
316 prompt_Create(struct server *s, struct bundle *bundle, int fd)
317 {
318   struct prompt *p = (struct prompt *)malloc(sizeof(struct prompt));
319 
320   if (p != NULL) {
321     p->desc.type = PROMPT_DESCRIPTOR;
322     p->desc.UpdateSet = prompt_UpdateSet;
323     p->desc.IsSet = prompt_IsSet;
324     p->desc.Read = prompt_Read;
325     p->desc.Write = prompt_Write;
326 
327     if (fd == PROMPT_STD) {
328       char *tty = ttyname(STDIN_FILENO);
329 
330       if (!tty) {
331         free(p);
332         return NULL;
333       }
334       p->fd_in = STDIN_FILENO;
335       p->fd_out = STDOUT_FILENO;
336       p->Term = stdout;
337       p->owner = NULL;
338       p->auth = LOCAL_AUTH;
339       p->src.type = "Controller";
340       strncpy(p->src.from, tty, sizeof p->src.from - 1);
341       p->src.from[sizeof p->src.from - 1] = '\0';
342       tcgetattr(p->fd_in, &p->oldtio);	/* Save original tty mode */
343     } else {
344       p->fd_in = p->fd_out = fd;
345       p->Term = fdopen(fd, "a+");
346       p->owner = s;
347       p->auth = *s->cfg.passwd ? LOCAL_NO_AUTH : LOCAL_AUTH;
348       p->src.type = "unknown";
349       *p->src.from = '\0';
350     }
351     p->TermMode = NULL;
352     p->nonewline = 1;
353     p->needprompt = 1;
354     p->readtilde = 0;
355     p->bundle = bundle;
356     log_RegisterPrompt(p);
357   }
358 
359   return p;
360 }
361 
362 void
363 prompt_Destroy(struct prompt *p, int verbose)
364 {
365   if (p) {
366     if (p->Term != stdout) {
367       fclose(p->Term);
368       close(p->fd_in);
369       if (p->fd_out != p->fd_in)
370         close(p->fd_out);
371       if (verbose)
372         log_Printf(LogPHASE, "%s: Client connection dropped.\n", p->src.from);
373     } else
374       prompt_TtyOldMode(p);
375 
376     log_UnRegisterPrompt(p);
377     free(p);
378   }
379 }
380 
381 void
382 prompt_Printf(struct prompt *p, const char *fmt,...)
383 {
384   if (p && p->active) {
385     va_list ap;
386 
387     va_start(ap, fmt);
388     prompt_vPrintf(p, fmt, ap);
389     va_end(ap);
390   }
391 }
392 
393 void
394 prompt_vPrintf(struct prompt *p, const char *fmt, va_list ap)
395 {
396   if (p && p->active) {
397     char nfmt[LINE_LEN];
398     const char *pfmt;
399 
400     if (p->TermMode) {
401       /* Stuff '\r' in front of '\n' 'cos we're in raw mode */
402       size_t len = strlen(fmt);
403 
404       if (len && len < sizeof nfmt - 1 && fmt[len-1] == '\n' &&
405           (len == 1 || fmt[len-2] != '\r')) {
406         strcpy(nfmt, fmt);
407         strcpy(nfmt + len - 1, "\r\n");
408         pfmt = nfmt;
409       } else
410         pfmt = fmt;
411     } else
412       pfmt = fmt;
413     vfprintf(p->Term, pfmt, ap);
414     fflush(p->Term);
415     p->nonewline = 1;
416   }
417 }
418 
419 void
420 prompt_TtyInit(struct prompt *p)
421 {
422   int stat, fd = p ? p->fd_in : STDIN_FILENO;
423   struct termios newtio;
424 
425   stat = fcntl(fd, F_GETFL, 0);
426   if (stat > 0) {
427     stat |= O_NONBLOCK;
428     fcntl(fd, F_SETFL, stat);
429   }
430 
431   if (p)
432     newtio = p->oldtio;
433   else
434     tcgetattr(fd, &newtio);
435 
436   newtio.c_lflag &= ~(ECHO | ISIG | ICANON);
437   newtio.c_iflag = 0;
438   newtio.c_oflag &= ~OPOST;
439   if (!p)
440     newtio.c_cc[VINTR] = _POSIX_VDISABLE;
441   newtio.c_cc[VMIN] = 1;
442   newtio.c_cc[VTIME] = 0;
443   newtio.c_cflag |= CS8;
444   tcsetattr(fd, TCSANOW, &newtio);
445   if (p)
446     p->comtio = newtio;
447 }
448 
449 /*
450  *  Set tty into command mode. We allow canonical input and echo processing.
451  */
452 void
453 prompt_TtyCommandMode(struct prompt *p)
454 {
455   struct termios newtio;
456   int stat;
457 
458   tcgetattr(p->fd_in, &newtio);
459   newtio.c_lflag |= (ECHO | ISIG | ICANON);
460   newtio.c_iflag = p->oldtio.c_iflag;
461   newtio.c_oflag |= OPOST;
462   tcsetattr(p->fd_in, TCSADRAIN, &newtio);
463 
464   stat = fcntl(p->fd_in, F_GETFL, 0);
465   if (stat > 0) {
466     stat |= O_NONBLOCK;
467     fcntl(p->fd_in, F_SETFL, stat);
468   }
469 
470   p->TermMode = NULL;
471 }
472 
473 /*
474  * Set tty into terminal mode which is used while we invoke term command.
475  */
476 void
477 prompt_TtyTermMode(struct prompt *p, struct datalink *dl)
478 {
479   int stat;
480 
481   if (p->Term == stdout)
482     tcsetattr(p->fd_in, TCSADRAIN, &p->comtio);
483 
484   stat = fcntl(p->fd_in, F_GETFL, 0);
485   if (stat > 0) {
486     stat &= ~O_NONBLOCK;
487     fcntl(p->fd_in, F_SETFL, stat);
488   }
489   p->TermMode = dl;
490 }
491 
492 void
493 prompt_TtyOldMode(struct prompt *p)
494 {
495   int stat;
496 
497   stat = fcntl(p->fd_in, F_GETFL, 0);
498   if (stat > 0) {
499     stat &= ~O_NONBLOCK;
500     fcntl(p->fd_in, F_SETFL, stat);
501   }
502 
503   if (p->Term == stdout)
504     tcsetattr(p->fd_in, TCSADRAIN, &p->oldtio);
505 }
506 
507 pid_t
508 prompt_pgrp(struct prompt *p)
509 {
510   return tcgetpgrp(p->fd_in);
511 }
512 
513 int
514 PasswdCommand(struct cmdargs const *arg)
515 {
516   const char *pass;
517 
518   if (!arg->prompt) {
519     log_Printf(LogWARN, "passwd: Cannot specify without a prompt\n");
520     return 0;
521   }
522 
523   if (arg->prompt->owner == NULL) {
524     log_Printf(LogWARN, "passwd: Not required\n");
525     return 0;
526   }
527 
528   if (arg->argc == arg->argn)
529     pass = "";
530   else if (arg->argc > arg->argn+1)
531     return -1;
532   else
533     pass = arg->argv[arg->argn];
534 
535   if (!strcmp(arg->prompt->owner->cfg.passwd, pass))
536     arg->prompt->auth = LOCAL_AUTH;
537   else
538     arg->prompt->auth = LOCAL_NO_AUTH;
539 
540   return 0;
541 }
542 
543 static struct pppTimer bgtimer;
544 
545 static void
546 prompt_TimedContinue(void *v)
547 {
548   prompt_Continue((struct prompt *)v);
549 }
550 
551 void
552 prompt_Continue(struct prompt *p)
553 {
554   timer_Stop(&bgtimer);
555   if (getpgrp() == prompt_pgrp(p)) {
556     prompt_TtyCommandMode(p);
557     p->nonewline = 1;
558     prompt_Required(p);
559     log_ActivatePrompt(p);
560   } else if (!p->owner) {
561     bgtimer.func = prompt_TimedContinue;
562     bgtimer.name = "prompt bg";
563     bgtimer.load = SECTICKS;
564     bgtimer.arg = p;
565     timer_Start(&bgtimer);
566   }
567 }
568 
569 void
570 prompt_Suspend(struct prompt *p)
571 {
572   if (getpgrp() == prompt_pgrp(p)) {
573     prompt_TtyOldMode(p);
574     log_DeactivatePrompt(p);
575   }
576 }
577