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[dragonfly.git] / libexec / getty / chat.c
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1 /*-
2 * Copyright (c) 1997
3 * David L Nugent <davidn@blaze.net.au>.
4 * All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, is permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice immediately at the beginning of the file, without modification,
12 * this list of conditions, and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. This work was done expressly for inclusion into FreeBSD. Other use
17 * is permitted provided this notation is included.
18 * 4. Absolutely no warranty of function or purpose is made by the authors.
19 * 5. Modifications may be freely made to this file providing the above
20 * conditions are met.
22 * Modem chat module - send/expect style functions for getty
23 * For semi-intelligent modem handling.
25 * $FreeBSD: src/libexec/getty/chat.c,v 1.6 1999/08/28 00:09:34 peter Exp $
26 * $DragonFly: src/libexec/getty/chat.c,v 1.6 2007/11/25 18:10:06 swildner Exp $
29 #include <sys/param.h>
30 #include <sys/stat.h>
31 #include <sys/ioctl.h>
32 #include <sys/resource.h>
33 #include <sys/ttydefaults.h>
34 #include <sys/utsname.h>
35 #include <ctype.h>
36 #include <errno.h>
37 #include <fcntl.h>
38 #include <libutil.h>
39 #include <locale.h>
40 #include <setjmp.h>
41 #include <signal.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <syslog.h>
45 #include <time.h>
46 #include <termios.h>
47 #include <unistd.h>
48 #include <sys/socket.h>
50 #include "gettytab.h"
51 #include "extern.h"
53 #define PAUSE_CH (unsigned char)'\xff' /* pause kludge */
55 #define CHATDEBUG_RECEIVE 0x01
56 #define CHATDEBUG_SEND 0x02
57 #define CHATDEBUG_EXPECT 0x04
58 #define CHATDEBUG_MISC 0x08
60 #define CHATDEBUG_DEFAULT 0
61 #define CHAT_DEFAULT_TIMEOUT 10
64 static int chat_debug = CHATDEBUG_DEFAULT;
65 static int chat_alarm = CHAT_DEFAULT_TIMEOUT; /* Default */
67 static volatile int alarmed = 0;
70 static void chat_alrm (int);
71 static int chat_unalarm (void);
72 static int getdigit (unsigned char **, int, int);
73 static char **read_chat (char **);
74 static char *cleanchr (char **, unsigned char);
75 static char *cleanstr (const unsigned char *, int);
76 static const char *result (int);
77 static int chat_expect (const char *);
78 static int chat_send (char const *);
82 * alarm signal handler
83 * handle timeouts in read/write
84 * change stdin to non-blocking mode to prevent
85 * possible hang in read().
88 static void
89 chat_alrm(int signo)
91 int on = 1;
93 alarm(1);
94 alarmed = 1;
95 signal(SIGALRM, chat_alrm);
96 ioctl(STDIN_FILENO, FIONBIO, &on);
101 * Turn back on blocking mode reset by chat_alrm()
104 static int
105 chat_unalarm(void)
107 int off = 0;
109 return ioctl(STDIN_FILENO, FIONBIO, &off);
114 * convert a string of a given base (octal/hex) to binary
117 static int
118 getdigit(unsigned char **ptr, int base, int max)
120 int i, val = 0;
121 char * q;
123 static const char xdigits[] = "0123456789abcdef";
125 for (i = 0, q = *ptr; i++ < max; ++q) {
126 int sval;
127 const char * s = strchr(xdigits, tolower(*q));
129 if (s == NULL || (sval = s - xdigits) >= base)
130 break;
131 val = (val * base) + sval;
133 *ptr = q;
134 return val;
139 * read_chat()
140 * Convert a whitespace delimtied string into an array
141 * of strings, being expect/send pairs
144 static char **
145 read_chat(char **chatstr)
147 char *str = *chatstr;
148 char **res = NULL;
150 if (str != NULL) {
151 char *tmp = NULL;
152 int l;
154 if ((l=strlen(str)) > 0 && (tmp=malloc(l + 1)) != NULL &&
155 (res=malloc((l / 2 + 1) * sizeof(char *))) != NULL) {
156 static char ws[] = " \t";
157 char * p;
159 for (l = 0, p = strtok(strcpy(tmp, str), ws);
160 p != NULL;
161 p = strtok(NULL, ws))
163 unsigned char *q, *r;
165 /* Read escapes */
166 for (q = r = (unsigned char *)p; *r; ++q)
168 if (*q == '\\')
170 /* handle special escapes */
171 switch (*++q)
173 case 'a': /* bell */
174 *r++ = '\a';
175 break;
176 case 'r': /* cr */
177 *r++ = '\r';
178 break;
179 case 'n': /* nl */
180 *r++ = '\n';
181 break;
182 case 'f': /* ff */
183 *r++ = '\f';
184 break;
185 case 'b': /* bs */
186 *r++ = '\b';
187 break;
188 case 'e': /* esc */
189 *r++ = 27;
190 break;
191 case 't': /* tab */
192 *r++ = '\t';
193 break;
194 case 'p': /* pause */
195 *r++ = PAUSE_CH;
196 break;
197 case 's':
198 case 'S': /* space */
199 *r++ = ' ';
200 break;
201 case 'x': /* hexdigit */
202 ++q;
203 *r++ = getdigit(&q, 16, 2);
204 --q;
205 break;
206 case '0': /* octal */
207 ++q;
208 *r++ = getdigit(&q, 8, 3);
209 --q;
210 break;
211 default: /* literal */
212 *r++ = *q;
213 break;
214 case 0: /* not past eos */
215 --q;
216 break;
218 } else {
219 /* copy standard character */
220 *r++ = *q;
224 /* Remove surrounding quotes, if any
226 if (*p == '"' || *p == '\'') {
227 q = strrchr(p+1, *p);
228 if (q != NULL && *q == *p && q[1] == '\0') {
229 *q = '\0';
230 strcpy(p, p+1);
234 res[l++] = p;
236 res[l] = NULL;
237 *chatstr = tmp;
238 return res;
240 free(tmp);
242 return res;
247 * clean a character for display (ctrl/meta character)
250 static char *
251 cleanchr(char **buf, unsigned char ch)
253 int l;
254 static char tmpbuf[5];
255 char * tmp = buf ? *buf : tmpbuf;
257 if (ch & 0x80) {
258 strcpy(tmp, "M-");
259 l = 2;
260 ch &= 0x7f;
261 } else
262 l = 0;
264 if (ch < 32) {
265 tmp[l++] = '^';
266 tmp[l++] = ch + '@';
267 } else if (ch == 127) {
268 tmp[l++] = '^';
269 tmp[l++] = '?';
270 } else
271 tmp[l++] = ch;
272 tmp[l] = '\0';
274 if (buf)
275 *buf = tmp + l;
276 return tmp;
281 * clean a string for display (ctrl/meta characters)
284 static char *
285 cleanstr(const unsigned char *s, int l)
287 static unsigned char * tmp = NULL;
288 static int tmplen = 0;
290 if (tmplen < l * 4 + 1)
291 tmp = realloc(tmp, tmplen = l * 4 + 1);
293 if (tmp == NULL) {
294 tmplen = 0;
295 return (char *)"(mem alloc error)";
296 } else {
297 int i = 0;
298 char * p = tmp;
300 while (i < l)
301 cleanchr(&p, s[i++]);
302 *p = '\0';
305 return tmp;
310 * return result as an pseudo-english word
313 static const char *
314 result(int r)
316 static const char * results[] = {
317 "OK", "MEMERROR", "IOERROR", "TIMEOUT"
319 return results[r & 3];
324 * chat_expect()
325 * scan input for an expected string
328 static int
329 chat_expect(const char *str)
331 int len, r = 0;
333 if (chat_debug & CHATDEBUG_EXPECT)
334 syslog(LOG_DEBUG, "chat_expect '%s'", cleanstr(str, strlen(str)));
336 if ((len = strlen(str)) > 0) {
337 int i = 0;
338 char * got;
340 if ((got = malloc(len + 1)) == NULL)
341 r = 1;
342 else {
344 memset(got, 0, len+1);
345 alarm(chat_alarm);
346 alarmed = 0;
348 while (r == 0 && i < len) {
349 if (alarmed)
350 r = 3;
351 else {
352 unsigned char ch;
354 if (read(STDIN_FILENO, &ch, 1) == 1) {
356 if (chat_debug & CHATDEBUG_RECEIVE)
357 syslog(LOG_DEBUG, "chat_recv '%s' m=%d",
358 cleanchr(NULL, ch), i);
360 if (ch == str[i])
361 got[i++] = ch;
362 else if (i > 0) {
363 int j = 1;
365 /* See if we can resync on a
366 * partial match in our buffer
368 while (j < i && memcmp(got + j, str, i - j) != 0)
369 j++;
370 if (j < i)
371 memcpy(got, got + j, i - j);
372 i -= j;
374 } else
375 r = alarmed ? 3 : 2;
378 alarm(0);
379 chat_unalarm();
380 alarmed = 0;
381 free(got);
385 if (chat_debug & CHATDEBUG_EXPECT)
386 syslog(LOG_DEBUG, "chat_expect %s", result(r));
388 return r;
393 * chat_send()
394 * send a chat string
397 static int
398 chat_send(char const *str)
400 int r = 0;
402 if (chat_debug && CHATDEBUG_SEND)
403 syslog(LOG_DEBUG, "chat_send '%s'", cleanstr(str, strlen(str)));
405 if (*str) {
406 alarm(chat_alarm);
407 alarmed = 0;
408 while (r == 0 && *str)
410 unsigned char ch = (unsigned char)*str++;
412 if (alarmed)
413 r = 3;
414 else if (ch == PAUSE_CH)
415 usleep(500000); /* 1/2 second */
416 else {
417 usleep(10000); /* be kind to modem */
418 if (write(STDOUT_FILENO, &ch, 1) != 1)
419 r = alarmed ? 3 : 2;
422 alarm(0);
423 chat_unalarm();
424 alarmed = 0;
427 if (chat_debug & CHATDEBUG_SEND)
428 syslog(LOG_DEBUG, "chat_send %s", result(r));
430 return r;
435 * getty_chat()
437 * Termination codes:
438 * -1 - no script supplied
439 * 0 - script terminated correctly
440 * 1 - invalid argument, expect string too large, etc.
441 * 2 - error on an I/O operation or fatal error condition
442 * 3 - timeout waiting for a simple string
444 * Parameters:
445 * char *scrstr - unparsed chat script
446 * timeout - seconds timeout
447 * debug - debug value (bitmask)
451 getty_chat(char *scrstr, int timeout, int debug)
453 int r = -1;
455 chat_alarm = timeout ? timeout : CHAT_DEFAULT_TIMEOUT;
456 chat_debug = debug;
458 if (scrstr != NULL) {
459 char **script;
461 if (chat_debug & CHATDEBUG_MISC)
462 syslog(LOG_DEBUG, "getty_chat script='%s'", scrstr);
464 if ((script = read_chat(&scrstr)) != NULL) {
465 int i = r = 0;
466 int off = 0;
467 sig_t old_alarm;
470 * We need to be in raw mode for all this
471 * Rely on caller...
474 old_alarm = signal(SIGALRM, chat_alrm);
475 chat_unalarm(); /* Force blocking mode at start */
478 * This is the send/expect loop
480 while (r == 0 && script[i] != NULL)
481 if ((r = chat_expect(script[i++])) == 0 && script[i] != NULL)
482 r = chat_send(script[i++]);
484 signal(SIGALRM, old_alarm);
485 free(script);
486 free(scrstr);
489 * Ensure stdin is in blocking mode
491 ioctl(STDIN_FILENO, FIONBIO, &off);
494 if (chat_debug & CHATDEBUG_MISC)
495 syslog(LOG_DEBUG, "getty_chat %s", result(r));
498 return r;