1 /* $NetBSD: timedc.c,v 1.22 2012/01/16 17:38:16 christos Exp $ */
2
3 /*-
4 * Copyright (c) 1985, 1993 The Regents of the University of California.
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 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1985, 1993\
35 The Regents of the University of California. All rights reserved.");
36 #endif /* not lint */
37
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)timedc.c 8.1 (Berkeley) 6/6/93";
41 #else
42 __RCSID("$NetBSD: timedc.c,v 1.22 2012/01/16 17:38:16 christos Exp $");
43 #endif
44 #endif /* not lint */
45
46 #include "timedc.h"
47 #include <ctype.h>
48 #include <setjmp.h>
49 #include <signal.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <syslog.h>
53 #include <unistd.h>
54 #include <fcntl.h>
55 #include <pwd.h>
56 #include <err.h>
57
58 int trace = 0;
59 FILE *fd = 0;
60 int margc;
61 int fromatty;
62 #define MAX_MARGV 20
63 char *margv[MAX_MARGV];
64 char cmdline[200];
65 jmp_buf toplevel;
66 static const struct cmd *getcmd(char *);
67 static int drop_privileges(void);
68
69 int
main(int argc,char * argv[])70 main(int argc, char *argv[])
71 {
72 const struct cmd *c;
73
74 fcntl(3, F_CLOSEM);
75 openlog("timedc", 0, LOG_AUTH);
76
77 /*
78 * security dictates!
79 */
80 if (priv_resources() < 0)
81 errx(EXIT_FAILURE, "Could not get privileged resources");
82 if (drop_privileges() < 0)
83 errx(EXIT_FAILURE, "Could not drop privileges");
84
85 if (--argc > 0) {
86 c = getcmd(*++argv);
87 if (c == (struct cmd *)-1) {
88 printf("?Ambiguous command\n");
89 exit(EXIT_FAILURE);
90 }
91 if (c == 0) {
92 printf("?Invalid command\n");
93 exit(EXIT_FAILURE);
94 }
95 (*c->c_handler)(argc, argv);
96 exit(EXIT_SUCCESS);
97 }
98
99 fromatty = isatty(fileno(stdin));
100 if (setjmp(toplevel))
101 putchar('\n');
102 (void) signal(SIGINT, intr);
103 for (;;) {
104 if (fromatty) {
105 printf("timedc> ");
106 (void) fflush(stdout);
107 }
108 if (fgets(cmdline, sizeof(cmdline), stdin) == NULL)
109 quit(0, NULL);
110 if (cmdline[0] == 0)
111 break;
112 if (makeargv()) {
113 printf("?Too many arguments\n");
114 continue;
115 }
116 if (margv[0] == 0)
117 continue;
118 c = getcmd(margv[0]);
119 if (c == (struct cmd *)-1) {
120 printf("?Ambiguous command\n");
121 continue;
122 }
123 if (c == 0) {
124 printf("?Invalid command\n");
125 continue;
126 }
127 (*c->c_handler)(margc, margv);
128 }
129 return 0;
130 }
131
132 void
intr(int signo)133 intr(int signo)
134 {
135 (void) signo;
136 if (!fromatty)
137 exit(EXIT_SUCCESS);
138 longjmp(toplevel, 1);
139 }
140
141
142 static const struct cmd *
getcmd(char * name)143 getcmd(char *name)
144 {
145 const char *p;
146 char *q;
147 const struct cmd *c, *found;
148 int nmatches, longest;
149 extern const struct cmd cmdtab[];
150 extern int NCMDS;
151
152 longest = 0;
153 nmatches = 0;
154 found = 0;
155 for (c = cmdtab; c < &cmdtab[NCMDS]; c++) {
156 p = c->c_name;
157 for (q = name; *q == *p++; q++)
158 if (*q == 0) /* exact match? */
159 return(c);
160 if (!*q) { /* the name was a prefix */
161 if (q - name > longest) {
162 longest = q - name;
163 nmatches = 1;
164 found = c;
165 } else if (q - name == longest)
166 nmatches++;
167 }
168 }
169 if (nmatches > 1)
170 return((struct cmd *)-1);
171 return(found);
172 }
173
174 /*
175 * Slice a string up into argc/argv.
176 */
177 int
makeargv(void)178 makeargv(void)
179 {
180 char *cp;
181 char **argp = margv;
182
183 margc = 0;
184 for (cp = cmdline; argp < &margv[MAX_MARGV - 1] && *cp;) {
185 while (isspace((unsigned char)*cp))
186 cp++;
187 if (*cp == '\0')
188 break;
189 *argp++ = cp;
190 margc += 1;
191 while (*cp != '\0' && !isspace((unsigned char)*cp))
192 cp++;
193 if (*cp == '\0')
194 break;
195 *cp++ = '\0';
196 }
197 if (margc == MAX_MARGV - 1)
198 return 1;
199 *argp++ = 0;
200 return 0;
201 }
202
203 #define HELPINDENT (sizeof ("directory"))
204
205 /*
206 * Help command.
207 */
208 void
help(int argc,char * argv[])209 help(int argc, char *argv[])
210 {
211 const struct cmd *c;
212 extern const struct cmd cmdtab[];
213
214 if (argc == 1) {
215 int i, j, w;
216 int columns, width = 0, lines;
217 extern int NCMDS;
218
219 printf("Commands may be abbreviated. Commands are:\n\n");
220 for (c = cmdtab; c < &cmdtab[NCMDS]; c++) {
221 int len = strlen(c->c_name);
222
223 if (len > width)
224 width = len;
225 }
226 width = (width + 8) &~ 7;
227 columns = 80 / width;
228 if (columns == 0)
229 columns = 1;
230 lines = (NCMDS + columns - 1) / columns;
231 for (i = 0; i < lines; i++) {
232 for (j = 0; j < columns; j++) {
233 c = cmdtab + j * lines + i;
234 printf("%s", c->c_name);
235 if (c + lines >= &cmdtab[NCMDS]) {
236 printf("\n");
237 break;
238 }
239 w = strlen(c->c_name);
240 while (w < width) {
241 w = (w + 8) &~ 7;
242 putchar('\t');
243 }
244 }
245 }
246 return;
247 }
248 while (--argc > 0) {
249 char *arg;
250 arg = *++argv;
251 c = getcmd(arg);
252 if (c == (struct cmd *)-1)
253 printf("?Ambiguous help command %s\n", arg);
254 else if (c == (struct cmd *)0)
255 printf("?Invalid help command %s\n", arg);
256 else
257 printf("%-*s\t%s\n", (int)HELPINDENT,
258 c->c_name, c->c_help);
259 }
260 }
261
262 static int
drop_privileges(void)263 drop_privileges(void)
264 {
265 static const char user[] = "_timedc";
266 const struct passwd *pw;
267 uid_t uid;
268 gid_t gid;
269
270 if ((pw = getpwnam(user)) == NULL) {
271 warnx("getpwnam(\"%s\") failed", user);
272 return -1;
273 }
274 uid = pw->pw_uid;
275 gid = pw->pw_gid;
276 if (setgroups(1, &gid)) {
277 warn("setgroups");
278 return -1;
279 }
280 if (setgid(gid)) {
281 warn("setgid");
282 return -1;
283 }
284 if (setuid(uid)) {
285 warn("setuid");
286 return -1;
287 }
288 return 0;
289 }
290