1 /*	$NetBSD: rkpty.c,v 1.1.1.2 2014/04/24 12:45:52 pettai Exp $	*/
2 
3 /*
4  * Copyright (c) 2008 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include "config.h"
37 
38 #ifndef HAVE_SYS_TYPES_H
39 #include <sys/types.h>
40 #endif
41 #ifdef HAVE_SYS_WAIT_H
42 #include <sys/wait.h>
43 #endif
44 #include <stdio.h>
45 #include <stdlib.h>
46 #ifdef HAVE_UNISTD_H
47 #include <unistd.h>
48 #endif
49 #ifdef HAVE_PTY_H
50 #include <pty.h>
51 #endif
52 #ifdef HAVE_UTIL_H
53 #include <util.h>
54 #endif
55 #ifdef HAVE_LIBUTIL_H
56 #include <libutil.h>
57 #endif
58 
59 #ifdef	STREAMSPTY
60 #include <stropts.h>
61 #endif /* STREAMPTY */
62 
63 #include <krb5/roken.h>
64 #include <krb5/getarg.h>
65 
66 struct command {
67     enum { CMD_EXPECT = 0, CMD_SEND, CMD_PASSWORD } type;
68     unsigned int lineno;
69     char *str;
70     struct command *next;
71 };
72 
73 /*
74  *
75  */
76 
77 static struct command *commands, **next = &commands;
78 
79 static sig_atomic_t alarmset = 0;
80 
81 static int timeout = 10;
82 static int verbose;
83 static int help_flag;
84 static int version_flag;
85 
86 static int master;
87 static int slave;
88 static char line[256] = { 0 };
89 
90 static void
caught_signal(int signo)91 caught_signal(int signo)
92 {
93     alarmset = signo;
94 }
95 
96 
97 static void
open_pty(void)98 open_pty(void)
99 {
100 #ifdef _AIX
101     printf("implement open_pty\n");
102     exit(77);
103 #endif
104 #if defined(HAVE_OPENPTY) || defined(__linux) || defined(__osf__) /* XXX */
105     if(openpty(&master, &slave, line, 0, 0) == 0)
106 	return;
107 #endif /* HAVE_OPENPTY .... */
108 #ifdef STREAMSPTY
109     {
110 	char *clone[] = {
111 	    "/dev/ptc",
112 	    "/dev/ptmx",
113 	    "/dev/ptm",
114 	    "/dev/ptym/clone",
115 	    NULL
116 	};
117 	char **q;
118 
119 	for(q = clone; *q; q++){
120 	    master = open(*q, O_RDWR);
121 	    if(master >= 0){
122 #ifdef HAVE_GRANTPT
123 		grantpt(master);
124 #endif
125 #ifdef HAVE_UNLOCKPT
126 		unlockpt(master);
127 #endif
128 		strlcpy(line, ptsname(master), sizeof(line));
129 		slave = open(line, O_RDWR);
130 		if (slave < 0)
131 		    errx(1, "failed to open slave when using %s", *q);
132 		ioctl(slave, I_PUSH, "ptem");
133 		ioctl(slave, I_PUSH, "ldterm");
134 
135 		return;
136 	    }
137 	}
138     }
139 #endif /* STREAMSPTY */
140 
141     /* more cases, like open /dev/ptmx, etc */
142 
143     exit(77);
144 }
145 
146 /*
147  *
148  */
149 
150 static char *
iscmd(const char * buf,const char * s)151 iscmd(const char *buf, const char *s)
152 {
153     size_t len = strlen(s);
154     if (strncmp(buf, s, len) != 0)
155 	return NULL;
156     return estrdup(buf + len);
157 }
158 
159 static void
parse_configuration(const char * fn)160 parse_configuration(const char *fn)
161 {
162     struct command *c;
163     char s[1024];
164     char *str;
165     unsigned int lineno = 0;
166     FILE *cmd;
167 
168     cmd = fopen(fn, "r");
169     if (cmd == NULL)
170 	err(1, "open: %s", fn);
171 
172     while (fgets(s, sizeof(s),  cmd) != NULL) {
173 
174 	s[strcspn(s, "#\n")] = '\0';
175 	lineno++;
176 
177 	c = calloc(1, sizeof(*c));
178 	if (c == NULL)
179 	    errx(1, "malloc");
180 
181 	c->lineno = lineno;
182 	(*next) = c;
183 	next = &(c->next);
184 
185 	if ((str = iscmd(s, "expect ")) != NULL) {
186 	    c->type = CMD_EXPECT;
187 	    c->str = str;
188 	} else if ((str = iscmd(s, "send ")) != NULL) {
189 	    c->type = CMD_SEND;
190 	    c->str = str;
191 	} else if ((str = iscmd(s, "password ")) != NULL) {
192 	    c->type = CMD_PASSWORD;
193 	    c->str = str;
194 	} else
195 	    errx(1, "Invalid command on line %d: %s", lineno, s);
196     }
197 
198     fclose(cmd);
199 }
200 
201 
202 /*
203  *
204  */
205 
206 static int
eval_parent(pid_t pid)207 eval_parent(pid_t pid)
208 {
209     struct command *c;
210     char in;
211     size_t len = 0;
212     ssize_t sret;
213 
214     for (c = commands; c != NULL; c = c->next) {
215 	switch(c->type) {
216 	case CMD_EXPECT:
217 	    if (verbose)
218 		printf("[expecting %s]", c->str);
219 	    len = 0;
220 	    alarm(timeout);
221 	    while((sret = read(master, &in, sizeof(in))) > 0) {
222 		alarm(timeout);
223 		printf("%c", in);
224 		if (c->str[len] != in) {
225 		    len = 0;
226 		    continue;
227 		}
228 		len++;
229 		if (c->str[len] == '\0')
230 		    break;
231 	    }
232 	    alarm(0);
233 	    if (alarmset == SIGALRM)
234 		errx(1, "timeout waiting for %s (line %u)",
235 		     c->str, c->lineno);
236 	    else if (alarmset)
237 		errx(1, "got a signal %d waiting for %s (line %u)",
238 		     alarmset, c->str, c->lineno);
239 	    if (sret <= 0)
240 		errx(1, "end command while waiting for %s (line %u)",
241 		     c->str, c->lineno);
242 	    break;
243 	case CMD_SEND:
244 	case CMD_PASSWORD: {
245 	    size_t i = 0;
246 	    const char *msg = (c->type == CMD_PASSWORD) ? "****" : c->str;
247 
248 	    if (verbose)
249 		printf("[send %s]", msg);
250 
251 	    len = strlen(c->str);
252 
253 	    while (i < len) {
254 		if (c->str[i] == '\\' && i < len - 1) {
255 		    char ctrl;
256 		    i++;
257 		    switch(c->str[i]) {
258 		    case 'n': ctrl = '\n'; break;
259 		    case 'r': ctrl = '\r'; break;
260 		    case 't': ctrl = '\t'; break;
261 		    default:
262 			errx(1, "unknown control char %c (line %u)",
263 			     c->str[i], c->lineno);
264 		    }
265 		    if (net_write(master, &ctrl, 1) != 1)
266 			errx(1, "command refused input (line %u)", c->lineno);
267 		} else {
268 		    if (net_write(master, &c->str[i], 1) != 1)
269 			errx(1, "command refused input (line %u)", c->lineno);
270 		}
271 		i++;
272 	    }
273 	    break;
274 	}
275 	default:
276 	    abort();
277 	}
278     }
279     while(read(master, &in, sizeof(in)) > 0)
280 	printf("%c", in);
281 
282     if (verbose)
283 	printf("[end of program]\n");
284 
285     /*
286      * Fetch status from child
287      */
288     {
289 	int ret, status;
290 
291 	ret = waitpid(pid, &status, 0);
292 	if (ret == -1)
293 	    err(1, "waitpid");
294 	if (WIFEXITED(status) && WEXITSTATUS(status))
295 	    return WEXITSTATUS(status);
296 	else if (WIFSIGNALED(status)) {
297 	    printf("killed by signal: %d\n", WTERMSIG(status));
298 	    return 1;
299 	}
300     }
301     return 0;
302 }
303 
304 /*
305  *
306  */
307 
308 static struct getargs args[] = {
309     { "timeout", 	't', arg_integer, &timeout, "timout", "seconds" },
310     { "verbose", 	'v', arg_counter, &verbose, "verbose debugging" },
311     { "version",	0, arg_flag,	&version_flag, "print version" },
312     { "help",		0, arg_flag,	&help_flag, NULL }
313 };
314 
315 static void
usage(int ret)316 usage(int ret)
317 {
318     arg_printusage (args, sizeof(args)/sizeof(*args), NULL, "infile command..");
319     exit (ret);
320 }
321 
322 int
main(int argc,char ** argv)323 main(int argc, char **argv)
324 {
325     int optidx = 0;
326     pid_t pid;
327 
328     setprogname(argv[0]);
329 
330     if(getarg(args, sizeof(args) / sizeof(args[0]), argc, argv, &optidx))
331 	usage(1);
332 
333     if (help_flag)
334 	usage (0);
335 
336     if (version_flag) {
337 	fprintf (stderr, "%s from %s-%s\n", getprogname(), PACKAGE, VERSION);
338 	return 0;
339     }
340 
341     argv += optidx;
342     argc -= optidx;
343 
344     if (argc < 2)
345 	usage(1);
346 
347     parse_configuration(argv[0]);
348 
349     argv += 1;
350 
351     open_pty();
352 
353     pid = fork();
354     switch (pid) {
355     case -1:
356 	err(1, "Failed to fork");
357     case 0:
358 
359 	if(setsid()<0)
360 	    err(1, "setsid");
361 
362 	dup2(slave, STDIN_FILENO);
363 	dup2(slave, STDOUT_FILENO);
364 	dup2(slave, STDERR_FILENO);
365 	closefrom(STDERR_FILENO + 1);
366 
367 	execvp(argv[0], argv); /* add NULL to end of array ? */
368 	err(1, "Failed to exec: %s", argv[0]);
369     default:
370 	close(slave);
371 	{
372 	    struct sigaction sa;
373 
374 	    sa.sa_handler = caught_signal;
375 	    sa.sa_flags = 0;
376 	    sigemptyset (&sa.sa_mask);
377 
378 	    sigaction(SIGALRM, &sa, NULL);
379 	}
380 
381 	return eval_parent(pid);
382     }
383 }
384