xref: /freebsd/usr.sbin/ppp/tty.c (revision ae477ca7da55f76d28859e1bd01cd1051e36f28f)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 1999 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 
29 #include <sys/param.h>
30 #include <sys/un.h>
31 #if defined(__OpenBSD__) || defined(__NetBSD__)
32 #include <sys/ioctl.h>
33 #endif
34 
35 #include <errno.h>
36 #include <fcntl.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <sysexits.h>
41 #include <sys/uio.h>
42 #include <termios.h>
43 #include <ttyent.h>
44 #include <unistd.h>
45 #ifndef NONETGRAPH
46 #include <netgraph.h>
47 #include <netgraph/ng_async.h>
48 #include <netgraph/ng_message.h>
49 #include <netgraph/ng_ppp.h>
50 #include <netgraph/ng_tty.h>
51 #endif
52 
53 #include "layer.h"
54 #include "defs.h"
55 #include "mbuf.h"
56 #include "log.h"
57 #include "timer.h"
58 #include "lqr.h"
59 #include "hdlc.h"
60 #include "throughput.h"
61 #include "fsm.h"
62 #include "lcp.h"
63 #include "ccp.h"
64 #include "link.h"
65 #include "async.h"
66 #include "descriptor.h"
67 #include "physical.h"
68 #include "mp.h"
69 #include "chat.h"
70 #include "auth.h"
71 #include "chap.h"
72 #include "cbcp.h"
73 #include "datalink.h"
74 #include "main.h"
75 #include "id.h"
76 #include "tty.h"
77 
78 #if defined(__mac68k__) || defined(__macppc__)
79 #undef	CRTS_IFLOW
80 #undef	CCTS_OFLOW
81 #define	CRTS_IFLOW	CDTRCTS
82 #define	CCTS_OFLOW	CDTRCTS
83 #endif
84 
85 #define	Online(dev)	((dev)->mbits & TIOCM_CD)
86 
87 struct ttydevice {
88   struct device dev;		/* What struct physical knows about */
89   struct pppTimer Timer;	/* CD checks */
90   int mbits;			/* Current DCD status */
91   int carrier_seconds;		/* seconds before CD is *required* */
92 #ifndef NONETGRAPH
93   struct {
94     unsigned speed;		/* Pre-line-discipline speed */
95     int fd;			/* Pre-line-discipline fd */
96     int disc;			/* Old line-discipline */
97   } real;
98   char hook[sizeof NG_ASYNC_HOOK_SYNC]; /* our ng_socket hook */
99   int cs;			/* A netgraph control socket (maybe) */
100 #endif
101   struct termios ios;		/* To be able to reset from raw mode */
102 };
103 
104 #define device2tty(d) ((d)->type == TTY_DEVICE ? (struct ttydevice *)d : NULL)
105 
106 unsigned
107 tty_DeviceSize(void)
108 {
109   return sizeof(struct ttydevice);
110 }
111 
112 /*
113  * tty_Timeout() watches the DCD signal and mentions it if it's status
114  * changes.
115  */
116 static void
117 tty_Timeout(void *data)
118 {
119   struct physical *p = data;
120   struct ttydevice *dev = device2tty(p->handler);
121   int ombits, change;
122 
123   timer_Stop(&dev->Timer);
124   dev->Timer.load = SECTICKS;		/* Once a second please */
125   timer_Start(&dev->Timer);
126   ombits = dev->mbits;
127 
128   if (p->fd >= 0) {
129     if (ioctl(p->fd, TIOCMGET, &dev->mbits) < 0) {
130       /* we must be a pty ? */
131       if (p->cfg.cd.necessity != CD_DEFAULT)
132         log_Printf(LogWARN, "%s: Carrier ioctl not supported, "
133                    "using ``set cd off''\n", p->link.name);
134       timer_Stop(&dev->Timer);
135       dev->mbits = TIOCM_CD;
136       return;
137     }
138   } else
139     dev->mbits = 0;
140 
141   if (ombits == -1) {
142     /* First time looking for carrier */
143     if (Online(dev))
144       log_Printf(LogPHASE, "%s: %s: CD detected\n", p->link.name, p->name.full);
145     else if (++dev->carrier_seconds >= dev->dev.cd.delay) {
146       if (dev->dev.cd.necessity == CD_REQUIRED)
147         log_Printf(LogPHASE, "%s: %s: Required CD not detected\n",
148                    p->link.name, p->name.full);
149       else {
150         log_Printf(LogPHASE, "%s: %s doesn't support CD\n",
151                    p->link.name, p->name.full);
152         dev->mbits = TIOCM_CD;		/* Dodgy null-modem cable ? */
153       }
154       timer_Stop(&dev->Timer);
155       /* tty_AwaitCarrier() will notice */
156     } else {
157       /* Keep waiting */
158       log_Printf(LogDEBUG, "%s: %s: Still no carrier (%d/%d)\n",
159                  p->link.name, p->name.full, dev->carrier_seconds,
160                  dev->dev.cd.delay);
161       dev->mbits = -1;
162     }
163   } else {
164     change = ombits ^ dev->mbits;
165     if (change & TIOCM_CD) {
166       if (dev->mbits & TIOCM_CD)
167         log_Printf(LogDEBUG, "%s: offline -> online\n", p->link.name);
168       else {
169         log_Printf(LogDEBUG, "%s: online -> offline\n", p->link.name);
170         log_Printf(LogPHASE, "%s: Carrier lost\n", p->link.name);
171         datalink_Down(p->dl, CLOSE_NORMAL);
172         timer_Stop(&dev->Timer);
173       }
174     } else
175       log_Printf(LogDEBUG, "%s: Still %sline\n", p->link.name,
176                  Online(dev) ? "on" : "off");
177   }
178 }
179 
180 static void
181 tty_StartTimer(struct physical *p)
182 {
183   struct ttydevice *dev = device2tty(p->handler);
184 
185   timer_Stop(&dev->Timer);
186   dev->Timer.load = SECTICKS;
187   dev->Timer.func = tty_Timeout;
188   dev->Timer.name = "tty CD";
189   dev->Timer.arg = p;
190   log_Printf(LogDEBUG, "%s: Using tty_Timeout [%p]\n",
191              p->link.name, tty_Timeout);
192   timer_Start(&dev->Timer);
193 }
194 
195 static int
196 tty_AwaitCarrier(struct physical *p)
197 {
198   struct ttydevice *dev = device2tty(p->handler);
199 
200   if (dev->dev.cd.necessity == CD_NOTREQUIRED || physical_IsSync(p))
201     return CARRIER_OK;
202 
203   if (dev->mbits == -1) {
204     if (dev->Timer.state == TIMER_STOPPED) {
205       dev->carrier_seconds = 0;
206       tty_StartTimer(p);
207     }
208     return CARRIER_PENDING;			/* Not yet ! */
209   }
210 
211   return Online(dev) ? CARRIER_OK : CARRIER_LOST;
212 }
213 
214 #ifdef NONETGRAPH
215 #define tty_SetAsyncParams	NULL
216 #define tty_Write		NULL
217 #define tty_Read		NULL
218 #else
219 
220 static int
221 isngtty(struct ttydevice *dev)
222 {
223   return dev->real.fd != -1;
224 }
225 
226 static void
227 tty_SetAsyncParams(struct physical *p, u_int32_t mymap, u_int32_t hismap)
228 {
229   struct ttydevice *dev = device2tty(p->handler);
230   char asyncpath[NG_PATHSIZ];
231   struct ng_async_cfg cfg;
232 
233   if (isngtty(dev)) {
234     /* Configure the async converter node */
235 
236     snprintf(asyncpath, sizeof asyncpath, ".:%s", dev->hook);
237     memset(&cfg, 0, sizeof cfg);
238     cfg.enabled = 1;
239     cfg.accm = mymap | hismap;
240     cfg.amru = MAX_MTU;
241     cfg.smru = MAX_MRU;
242     log_Printf(LogDEBUG, "Configure async node at %s\n", asyncpath);
243     if (NgSendMsg(dev->cs, asyncpath, NGM_ASYNC_COOKIE,
244                   NGM_ASYNC_CMD_SET_CONFIG, &cfg, sizeof cfg) < 0)
245       log_Printf(LogWARN, "%s: Can't configure async node at %s\n",
246                  p->link.name, asyncpath);
247   } else
248     /* No netgraph node, just config the async layer */
249     async_SetLinkParams(&p->async, mymap, hismap);
250 }
251 
252 static int
253 LoadLineDiscipline(struct physical *p)
254 {
255   struct ttydevice *dev = device2tty(p->handler);
256   u_char rbuf[sizeof(struct ng_mesg) + sizeof(struct nodeinfo)];
257   struct ng_mesg *reply;
258   struct nodeinfo *info;
259   char ttypath[NG_NODESIZ];
260   struct ngm_mkpeer ngm;
261   struct ngm_connect ngc;
262   int ldisc, cs, ds, hot;
263   unsigned speed;
264 
265   /*
266    * Don't use the netgraph line discipline for now.  Using it works, but
267    * carrier cannot be detected via TIOCMGET and the device doesn't become
268    * selectable with 0 bytes to read when carrier is lost :(
269    */
270   return 0;
271 
272   reply = (struct ng_mesg *)rbuf;
273   info = (struct nodeinfo *)reply->data;
274 
275   loadmodules(LOAD_VERBOSLY, "netgraph", "ng_tty", "ng_async", "ng_socket",
276               NULL);
277 
278   /* Get the speed before loading the line discipline */
279   speed = physical_GetSpeed(p);
280 
281   if (ioctl(p->fd, TIOCGETD, &dev->real.disc) < 0) {
282     log_Printf(LogDEBUG, "%s: Couldn't get tty line discipline\n",
283                p->link.name);
284     return 0;
285   }
286   ldisc = NETGRAPHDISC;
287   if (ID0ioctl(p->fd, TIOCSETD, &ldisc) < 0) {
288     log_Printf(LogDEBUG, "%s: Couldn't set NETGRAPHDISC line discipline\n",
289                p->link.name);
290     return 0;
291   }
292 
293   /* Get the name of the tty node */
294   if (ioctl(p->fd, NGIOCGINFO, info) < 0) {
295     log_Printf(LogWARN, "%s: ioctl(NGIOCGINFO): %s\n", p->link.name,
296                strerror(errno));
297     ID0ioctl(p->fd, TIOCSETD, &dev->real.disc);
298     return 0;
299   }
300   snprintf(ttypath, sizeof ttypath, "%s:", info->name);
301 
302   /* Create a socket node for our endpoint (and to send messages via) */
303   if (ID0NgMkSockNode(NULL, &cs, &ds) == -1) {
304     log_Printf(LogWARN, "%s: NgMkSockNode: %s\n", p->link.name,
305                strerror(errno));
306     ID0ioctl(p->fd, TIOCSETD, &dev->real.disc);
307     return 0;
308   }
309 
310   /* Set the ``hot char'' on the TTY node */
311   hot = HDLC_SYN;
312   log_Printf(LogDEBUG, "%s: Set tty hotchar to 0x%02x\n", p->link.name, hot);
313   if (NgSendMsg(cs, ttypath, NGM_TTY_COOKIE,
314       NGM_TTY_SET_HOTCHAR, &hot, sizeof hot) < 0) {
315     log_Printf(LogWARN, "%s: Can't set hot char\n", p->link.name);
316     goto failed;
317   }
318 
319   /* Attach an async converter node */
320   snprintf(ngm.type, sizeof ngm.type, "%s", NG_ASYNC_NODE_TYPE);
321   snprintf(ngm.ourhook, sizeof ngm.ourhook, "%s", NG_TTY_HOOK);
322   snprintf(ngm.peerhook, sizeof ngm.peerhook, "%s", NG_ASYNC_HOOK_ASYNC);
323   log_Printf(LogDEBUG, "%s: Send mkpeer async:%s to %s:%s\n", p->link.name,
324              ngm.peerhook, ttypath, ngm.ourhook);
325   if (NgSendMsg(cs, ttypath, NGM_GENERIC_COOKIE,
326       NGM_MKPEER, &ngm, sizeof ngm) < 0) {
327     log_Printf(LogWARN, "%s: Can't create %s node\n", p->link.name,
328                NG_ASYNC_NODE_TYPE);
329     goto failed;
330   }
331 
332   /* Connect the async node to our socket */
333   snprintf(ngc.path, sizeof ngc.path, "%s%s", ttypath, NG_TTY_HOOK);
334   snprintf(ngc.peerhook, sizeof ngc.peerhook, "%s", NG_ASYNC_HOOK_SYNC);
335   memcpy(ngc.ourhook, ngc.peerhook, sizeof ngc.ourhook);
336   log_Printf(LogDEBUG, "%s: Send connect %s:%s to .:%s\n", p->link.name,
337              ngc.path, ngc.peerhook, ngc.ourhook);
338   if (NgSendMsg(cs, ".:", NGM_GENERIC_COOKIE, NGM_CONNECT,
339       &ngc, sizeof ngc) < 0) {
340     log_Printf(LogWARN, "%s: Can't connect .:%s -> %s.%s: %s\n",
341                p->link.name, ngc.ourhook, ngc.path, ngc.peerhook,
342                strerror(errno));
343     goto failed;
344   }
345 
346   /* Get the async node id */
347   if (NgSendMsg(cs, ngc.path, NGM_GENERIC_COOKIE, NGM_NODEINFO, NULL, 0) < 0) {
348     log_Printf(LogWARN, "%s: Can't request async node info at %s: %s\n",
349                p->link.name, ngc.path, strerror(errno));
350     goto failed;
351   }
352   if (NgRecvMsg(cs, reply, sizeof rbuf, NULL) < 0) {
353     log_Printf(LogWARN, "%s: Can't obtain async node info at %s: %s\n",
354                p->link.name, ngc.path, strerror(errno));
355     goto failed;
356   }
357 
358   /* All done, set up our device state */
359   snprintf(dev->hook, sizeof dev->hook, "%s", ngc.ourhook);
360   dev->cs = cs;
361   dev->real.fd = p->fd;
362   p->fd = ds;
363   dev->real.speed = speed;
364   physical_SetSync(p);
365 
366   tty_SetAsyncParams(p, 0xffffffff, 0xffffffff);
367   physical_SetupStack(p, dev->dev.name, PHYSICAL_NOFORCE);
368   log_Printf(LogPHASE, "%s: Loaded netgraph tty line discipline\n",
369              p->link.name);
370 
371   return 1;
372 
373 failed:
374   ID0ioctl(p->fd, TIOCSETD, &dev->real.disc);
375   close(ds);
376   close(cs);
377 
378   return 0;
379 }
380 
381 static void
382 UnloadLineDiscipline(struct physical *p)
383 {
384   struct ttydevice *dev = device2tty(p->handler);
385 
386   if (isngtty(dev)) {
387     if (!physical_SetSpeed(p, dev->real.speed))
388       log_Printf(LogWARN, "Couldn't reset tty speed to %d\n", dev->real.speed);
389     dev->real.speed = 0;
390     close(p->fd);
391     p->fd = dev->real.fd;
392     dev->real.fd = -1;
393     close(dev->cs);
394     dev->cs = -1;
395     *dev->hook = '\0';
396     if (ID0ioctl(p->fd, TIOCSETD, &dev->real.disc) == 0) {
397       physical_SetupStack(p, dev->dev.name, PHYSICAL_NOFORCE);
398       log_Printf(LogPHASE, "%s: Unloaded netgraph tty line discipline\n",
399                  p->link.name);
400     } else
401       log_Printf(LogWARN, "%s: Failed to unload netgraph tty line discipline\n",
402                  p->link.name);
403   }
404 }
405 
406 static ssize_t
407 tty_Write(struct physical *p, const void *v, size_t n)
408 {
409   struct ttydevice *dev = device2tty(p->handler);
410 
411   if (isngtty(dev))
412     return NgSendData(p->fd, dev->hook, v, n) == -1 ? -1 : (ssize_t)n;
413   else
414     return write(p->fd, v, n);
415 }
416 
417 static ssize_t
418 tty_Read(struct physical *p, void *v, size_t n)
419 {
420   struct ttydevice *dev = device2tty(p->handler);
421   char hook[sizeof NG_ASYNC_HOOK_SYNC];
422 
423   if (isngtty(dev))
424     return NgRecvData(p->fd, v, n, hook);
425   else
426     return read(p->fd, v, n);
427 }
428 
429 #endif /* NETGRAPH */
430 
431 static int
432 tty_Raw(struct physical *p)
433 {
434   struct ttydevice *dev = device2tty(p->handler);
435   struct termios ios;
436   int oldflag;
437 
438   log_Printf(LogDEBUG, "%s: Entering tty_Raw\n", p->link.name);
439 
440   if (p->type != PHYS_DIRECT && p->fd >= 0 && !Online(dev))
441     log_Printf(LogDEBUG, "%s: Raw: descriptor = %d, mbits = %x\n",
442               p->link.name, p->fd, dev->mbits);
443 
444   if (!physical_IsSync(p)) {
445 #ifndef NONETGRAPH
446     if (!LoadLineDiscipline(p))
447 #endif
448     {
449       tcgetattr(p->fd, &ios);
450       cfmakeraw(&ios);
451       if (p->cfg.rts_cts)
452         ios.c_cflag |= CLOCAL | CCTS_OFLOW | CRTS_IFLOW;
453       else
454         ios.c_cflag |= CLOCAL;
455 
456       if (p->type != PHYS_DEDICATED)
457         ios.c_cflag |= HUPCL;
458 
459       if (tcsetattr(p->fd, TCSANOW, &ios) == -1)
460         log_Printf(LogWARN, "%s: tcsetattr: Failed configuring device\n",
461                    p->link.name);
462     }
463   }
464 
465   oldflag = fcntl(p->fd, F_GETFL, 0);
466   if (oldflag < 0)
467     return 0;
468   fcntl(p->fd, F_SETFL, oldflag | O_NONBLOCK);
469 
470   return 1;
471 }
472 
473 static void
474 tty_Offline(struct physical *p)
475 {
476   struct ttydevice *dev = device2tty(p->handler);
477 
478   if (p->fd >= 0) {
479     timer_Stop(&dev->Timer);
480     dev->mbits &= ~TIOCM_DTR;	/* XXX: Hmm, what's this supposed to do ? */
481     if (Online(dev)) {
482       struct termios tio;
483 
484       tcgetattr(p->fd, &tio);
485       if (cfsetspeed(&tio, B0) == -1 || tcsetattr(p->fd, TCSANOW, &tio) == -1)
486         log_Printf(LogWARN, "%s: Unable to set physical to speed 0\n",
487                    p->link.name);
488     }
489   }
490 }
491 
492 static void
493 tty_Cooked(struct physical *p)
494 {
495   struct ttydevice *dev = device2tty(p->handler);
496   int oldflag;
497 
498   tty_Offline(p);	/* In case of emergency close()s */
499 
500   tcflush(p->fd, TCIOFLUSH);
501 
502   if (!physical_IsSync(p) && tcsetattr(p->fd, TCSAFLUSH, &dev->ios) == -1)
503     log_Printf(LogWARN, "%s: tcsetattr: Unable to restore device settings\n",
504                p->link.name);
505 
506 #ifndef NONETGRAPH
507   UnloadLineDiscipline(p);
508 #endif
509 
510   if ((oldflag = fcntl(p->fd, F_GETFL, 0)) != -1)
511     fcntl(p->fd, F_SETFL, oldflag & ~O_NONBLOCK);
512 }
513 
514 static void
515 tty_StopTimer(struct physical *p)
516 {
517   struct ttydevice *dev = device2tty(p->handler);
518 
519   timer_Stop(&dev->Timer);
520 }
521 
522 static void
523 tty_Free(struct physical *p)
524 {
525   struct ttydevice *dev = device2tty(p->handler);
526 
527   tty_Offline(p);	/* In case of emergency close()s */
528   free(dev);
529 }
530 
531 static unsigned
532 tty_Speed(struct physical *p)
533 {
534   struct termios ios;
535 
536   if (tcgetattr(p->fd, &ios) == -1)
537     return 0;
538 
539   return SpeedToUnsigned(cfgetispeed(&ios));
540 }
541 
542 static const char *
543 tty_OpenInfo(struct physical *p)
544 {
545   struct ttydevice *dev = device2tty(p->handler);
546   static char buf[13];
547 
548   if (Online(dev))
549     strcpy(buf, "with");
550   else
551     strcpy(buf, "no");
552   strcat(buf, " carrier");
553 
554   return buf;
555 }
556 
557 static int
558 tty_Slot(struct physical *p)
559 {
560   struct ttyent *ttyp;
561   int slot;
562 
563   setttyent();
564   for (slot = 1; (ttyp = getttyent()); ++slot)
565     if (!strcmp(ttyp->ty_name, p->name.base)) {
566       endttyent();
567       return slot;
568     }
569 
570   endttyent();
571   return -1;
572 }
573 
574 static void
575 tty_device2iov(struct device *d, struct iovec *iov, int *niov,
576                int maxiov __unused,
577 #ifndef NONETGRAPH
578                int *auxfd, int *nauxfd
579 #else
580                int *auxfd __unused, int *nauxfd __unused
581 #endif
582                )
583 {
584   struct ttydevice *dev;
585   int sz = physical_MaxDeviceSize();
586 
587   iov[*niov].iov_base = d = realloc(d, sz);
588   if (d == NULL) {
589     log_Printf(LogALERT, "Failed to allocate memory: %d\n", sz);
590     AbortProgram(EX_OSERR);
591   }
592   iov[*niov].iov_len = sz;
593   (*niov)++;
594 
595   dev = device2tty(d);
596 
597 #ifndef NONETGRAPH
598   if (dev->cs >= 0) {
599     *auxfd = dev->cs;
600     (*nauxfd)++;
601   }
602 #endif
603 
604   if (dev->Timer.state != TIMER_STOPPED) {
605     timer_Stop(&dev->Timer);
606     dev->Timer.state = TIMER_RUNNING;
607   }
608 }
609 
610 static struct device basettydevice = {
611   TTY_DEVICE,
612   "tty",
613   0,
614   { CD_VARIABLE, DEF_TTYCDDELAY },
615   tty_AwaitCarrier,
616   NULL,
617   tty_Raw,
618   tty_Offline,
619   tty_Cooked,
620   tty_SetAsyncParams,
621   tty_StopTimer,
622   tty_Free,
623   tty_Read,
624   tty_Write,
625   tty_device2iov,
626   tty_Speed,
627   tty_OpenInfo,
628   tty_Slot
629 };
630 
631 struct device *
632 tty_iov2device(int type, struct physical *p, struct iovec *iov, int *niov,
633                int maxiov __unused,
634 #ifndef NONETGRAPH
635                int *auxfd, int *nauxfd
636 #else
637                int *auxfd __unused, int *nauxfd __unused
638 #endif
639                )
640 {
641   if (type == TTY_DEVICE) {
642     struct ttydevice *dev = (struct ttydevice *)iov[(*niov)++].iov_base;
643 
644     dev = realloc(dev, sizeof *dev);	/* Reduce to the correct size */
645     if (dev == NULL) {
646       log_Printf(LogALERT, "Failed to allocate memory: %d\n",
647                  (int)(sizeof *dev));
648       AbortProgram(EX_OSERR);
649     }
650 
651 #ifndef NONETGRAPH
652     if (*nauxfd) {
653       dev->cs = *auxfd;
654       (*nauxfd)--;
655     } else
656       dev->cs = -1;
657 #endif
658 
659     /* Refresh function pointers etc */
660     memcpy(&dev->dev, &basettydevice, sizeof dev->dev);
661 
662     physical_SetupStack(p, dev->dev.name, PHYSICAL_NOFORCE);
663     if (dev->Timer.state != TIMER_STOPPED) {
664       dev->Timer.state = TIMER_STOPPED;
665       p->handler = &dev->dev;		/* For the benefit of StartTimer */
666       tty_StartTimer(p);
667     }
668     return &dev->dev;
669   }
670 
671   return NULL;
672 }
673 
674 struct device *
675 tty_Create(struct physical *p)
676 {
677   struct ttydevice *dev;
678   struct termios ios;
679   int oldflag;
680 
681   if (p->fd < 0 || !isatty(p->fd))
682     /* Don't want this */
683     return NULL;
684 
685   if (*p->name.full == '\0') {
686     physical_SetDevice(p, ttyname(p->fd));
687     log_Printf(LogDEBUG, "%s: Input is a tty (%s)\n",
688                p->link.name, p->name.full);
689   } else
690     log_Printf(LogDEBUG, "%s: Opened %s\n", p->link.name, p->name.full);
691 
692   /* We're gonna return a ttydevice (unless something goes horribly wrong) */
693 
694   if ((dev = malloc(sizeof *dev)) == NULL) {
695     /* Complete failure - parent doesn't continue trying to ``create'' */
696     close(p->fd);
697     p->fd = -1;
698     return NULL;
699   }
700 
701   memcpy(&dev->dev, &basettydevice, sizeof dev->dev);
702   memset(&dev->Timer, '\0', sizeof dev->Timer);
703   dev->mbits = -1;
704 #ifndef NONETGRAPH
705   dev->real.speed = 0;
706   dev->real.fd = -1;
707   dev->real.disc = -1;
708   *dev->hook = '\0';
709 #endif
710   tcgetattr(p->fd, &ios);
711   dev->ios = ios;
712 
713   if (p->cfg.cd.necessity != CD_DEFAULT)
714     /* Any override is ok for the tty device */
715     dev->dev.cd = p->cfg.cd;
716 
717   log_Printf(LogDEBUG, "%s: tty_Create: physical (get): fd = %d,"
718              " iflag = %lx, oflag = %lx, cflag = %lx\n", p->link.name, p->fd,
719              (u_long)ios.c_iflag, (u_long)ios.c_oflag, (u_long)ios.c_cflag);
720 
721   cfmakeraw(&ios);
722   if (p->cfg.rts_cts)
723     ios.c_cflag |= CLOCAL | CCTS_OFLOW | CRTS_IFLOW;
724   else {
725     ios.c_cflag |= CLOCAL;
726     ios.c_iflag |= IXOFF;
727   }
728   ios.c_iflag |= IXON;
729   if (p->type != PHYS_DEDICATED)
730     ios.c_cflag |= HUPCL;
731 
732   if (p->type != PHYS_DIRECT) {
733       /* Change tty speed when we're not in -direct mode */
734       ios.c_cflag &= ~(CSIZE | PARODD | PARENB);
735       ios.c_cflag |= p->cfg.parity;
736       if (cfsetspeed(&ios, UnsignedToSpeed(p->cfg.speed)) == -1)
737 	log_Printf(LogWARN, "%s: %s: Unable to set speed to %d\n",
738 		  p->link.name, p->name.full, p->cfg.speed);
739   }
740 
741   if (tcsetattr(p->fd, TCSADRAIN, &ios) == -1) {
742     log_Printf(LogWARN, "%s: tcsetattr: Failed configuring device\n",
743                p->link.name);
744     if (p->type != PHYS_DIRECT && p->cfg.speed > 115200)
745       log_Printf(LogWARN, "%.*s             Perhaps the speed is unsupported\n",
746                  (int)strlen(p->link.name), "");
747   }
748 
749   log_Printf(LogDEBUG, "%s: physical (put): iflag = %lx, oflag = %lx, "
750             "cflag = %lx\n", p->link.name, (u_long)ios.c_iflag,
751             (u_long)ios.c_oflag, (u_long)ios.c_cflag);
752 
753   oldflag = fcntl(p->fd, F_GETFL, 0);
754   if (oldflag < 0) {
755     /* Complete failure - parent doesn't continue trying to ``create'' */
756 
757     log_Printf(LogWARN, "%s: Open: Cannot get physical flags: %s\n",
758                p->link.name, strerror(errno));
759     tty_Cooked(p);
760     close(p->fd);
761     p->fd = -1;
762     free(dev);
763     return NULL;
764   } else
765     fcntl(p->fd, F_SETFL, oldflag & ~O_NONBLOCK);
766 
767   physical_SetupStack(p, dev->dev.name, PHYSICAL_NOFORCE);
768 
769   return &dev->dev;
770 }
771