summaryrefslogtreecommitdiff
path: root/source4/heimdal/lib/roken/simple_exec.c
blob: 97679d7e4175e506a274ffbccacadb82f5ad4ba0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
/*
 * Copyright (c) 1998 - 2001, 2004 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden).
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <config.h>

#include <stdarg.h>
#include <stdlib.h>
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <errno.h>

#include "roken.h"

#define EX_NOEXEC	126
#define EX_NOTFOUND	127

/* return values:
   SE_E_UNSPECIFIED   on `unspecified' system errors
   SE_E_FORKFAILED    on fork failures
   SE_E_WAITPIDFAILED on waitpid errors
   SE_E_EXECTIMEOUT   exec timeout
   0-   is return value from subprocess
   SE_E_NOEXEC        if the program couldn't be executed
   SE_E_NOTFOUND      if the program couldn't be found
   128- is 128 + signal that killed subprocess

   possible values `func' can return:
   ((time_t)-2)		exit loop w/o killing child and return
   			`exec timeout'/-4 from simple_exec
   ((time_t)-1)		kill child with SIGTERM and wait for child to exit
   0			don't timeout again
   n			seconds to next timeout
   */

static int sig_alarm;

static RETSIGTYPE
sigtimeout(int sig)
{
    sig_alarm = 1;
    SIGRETURN(0);
}

ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
wait_for_process_timed(pid_t pid, time_t (*func)(void *),
		       void *ptr, time_t timeout)
{
    RETSIGTYPE (*old_func)(int sig) = NULL;
    unsigned int oldtime = 0;
    int ret;

    sig_alarm = 0;

    if (func) {
	old_func = signal(SIGALRM, sigtimeout);
	oldtime = alarm(timeout);
    }

    while(1) {
	int status;

	while(waitpid(pid, &status, 0) < 0) {
	    if (errno != EINTR) {
		ret = SE_E_WAITPIDFAILED;
		goto out;
	    }
	    if (func == NULL)
		continue;
	    if (sig_alarm == 0)
		continue;
	    timeout = (*func)(ptr);
	    if (timeout == (time_t)-1) {
		kill(pid, SIGTERM);
		continue;
	    } else if (timeout == (time_t)-2) {
		ret = SE_E_EXECTIMEOUT;
		goto out;
	    }
	    alarm(timeout);
	}
	if(WIFSTOPPED(status))
	    continue;
	if(WIFEXITED(status)) {
	    ret = WEXITSTATUS(status);
	    break;
	}
	if(WIFSIGNALED(status)) {
	    ret = WTERMSIG(status) + 128;
	    break;
	}
    }
 out:
    if (func) {
	signal(SIGALRM, old_func);
	alarm(oldtime);
    }
    return ret;
}

ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
wait_for_process(pid_t pid)
{
    return wait_for_process_timed(pid, NULL, NULL, 0);
}

ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
pipe_execv(FILE **stdin_fd, FILE **stdout_fd, FILE **stderr_fd,
	   const char *file, ...)
{
    int in_fd[2], out_fd[2], err_fd[2];
    pid_t pid;
    va_list ap;
    char **argv;

    if(stdin_fd != NULL)
	pipe(in_fd);
    if(stdout_fd != NULL)
	pipe(out_fd);
    if(stderr_fd != NULL)
	pipe(err_fd);
    pid = fork();
    switch(pid) {
    case 0:
	va_start(ap, file);
	argv = vstrcollect(&ap);
	va_end(ap);
	if(argv == NULL)
	    exit(-1);

	/* close pipes we're not interested in */
	if(stdin_fd != NULL)
	    close(in_fd[1]);
	if(stdout_fd != NULL)
	    close(out_fd[0]);
	if(stderr_fd != NULL)
	    close(err_fd[0]);

	/* pipe everything caller doesn't care about to /dev/null */
	if(stdin_fd == NULL)
	    in_fd[0] = open(_PATH_DEVNULL, O_RDONLY);
	if(stdout_fd == NULL)
	    out_fd[1] = open(_PATH_DEVNULL, O_WRONLY);
	if(stderr_fd == NULL)
	    err_fd[1] = open(_PATH_DEVNULL, O_WRONLY);

	/* move to proper descriptors */
	if(in_fd[0] != STDIN_FILENO) {
	    dup2(in_fd[0], STDIN_FILENO);
	    close(in_fd[0]);
	}
	if(out_fd[1] != STDOUT_FILENO) {
	    dup2(out_fd[1], STDOUT_FILENO);
	    close(out_fd[1]);
	}
	if(err_fd[1] != STDERR_FILENO) {
	    dup2(err_fd[1], STDERR_FILENO);
	    close(err_fd[1]);
	}

	closefrom(3);

	execv(file, argv);
	exit((errno == ENOENT) ? EX_NOTFOUND : EX_NOEXEC);
    case -1:
	if(stdin_fd != NULL) {
	    close(in_fd[0]);
	    close(in_fd[1]);
	}
	if(stdout_fd != NULL) {
	    close(out_fd[0]);
	    close(out_fd[1]);
	}
	if(stderr_fd != NULL) {
	    close(err_fd[0]);
	    close(err_fd[1]);
	}
	return SE_E_FORKFAILED;
    default:
	if(stdin_fd != NULL) {
	    close(in_fd[0]);
	    *stdin_fd = fdopen(in_fd[1], "w");
	}
	if(stdout_fd != NULL) {
	    close(out_fd[1]);
	    *stdout_fd = fdopen(out_fd[0], "r");
	}
	if(stderr_fd != NULL) {
	    close(err_fd[1]);
	    *stderr_fd = fdopen(err_fd[0], "r");
	}
    }
    return pid;
}

ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
simple_execvp_timed(const char *file, char *const args[],
		    time_t (*func)(void *), void *ptr, time_t timeout)
{
    pid_t pid = fork();
    switch(pid){
    case -1:
	return SE_E_FORKFAILED;
    case 0:
	execvp(file, args);
	exit((errno == ENOENT) ? EX_NOTFOUND : EX_NOEXEC);
    default:
	return wait_for_process_timed(pid, func, ptr, timeout);
    }
}

ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
simple_execvp(const char *file, char *const args[])
{
    return simple_execvp_timed(file, args, NULL, NULL, 0);
}

/* gee, I'd like a execvpe */
ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
simple_execve_timed(const char *file, char *const args[], char *const envp[],
		    time_t (*func)(void *), void *ptr, time_t timeout)
{
    pid_t pid = fork();
    switch(pid){
    case -1:
	return SE_E_FORKFAILED;
    case 0:
	execve(file, args, envp);
	exit((errno == ENOENT) ? EX_NOTFOUND : EX_NOEXEC);
    default:
	return wait_for_process_timed(pid, func, ptr, timeout);
    }
}

ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
simple_execve(const char *file, char *const args[], char *const envp[])
{
    return simple_execve_timed(file, args, envp, NULL, NULL, 0);
}

ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
simple_execlp(const char *file, ...)
{
    va_list ap;
    char **argv;
    int ret;

    va_start(ap, file);
    argv = vstrcollect(&ap);
    va_end(ap);
    if(argv == NULL)
	return SE_E_UNSPECIFIED;
    ret = simple_execvp(file, argv);
    free(argv);
    return ret;
}

ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
simple_execle(const char *file, ... /* ,char *const envp[] */)
{
    va_list ap;
    char **argv;
    char *const* envp;
    int ret;

    va_start(ap, file);
    argv = vstrcollect(&ap);
    envp = va_arg(ap, char **);
    va_end(ap);
    if(argv == NULL)
	return SE_E_UNSPECIFIED;
    ret = simple_execve(file, argv, envp);
    free(argv);
    return ret;
}