1 /* $NetBSD: rmjob.c,v 1.25 2009/07/13 19:05:41 roy Exp $ */
2
3 /*
4 * Copyright (c) 1983, 1993
5 * The Regents of the University of California. 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 #if 0
35 static char sccsid[] = "@(#)rmjob.c 8.2 (Berkeley) 4/28/95";
36 #else
37 __RCSID("$NetBSD: rmjob.c,v 1.25 2009/07/13 19:05:41 roy Exp $");
38 #endif
39 #endif /* not lint */
40
41 #include <sys/param.h>
42
43 #include <signal.h>
44 #include <errno.h>
45 #include <dirent.h>
46 #include <unistd.h>
47 #include <stdlib.h>
48 #include <stdio.h>
49 #include <string.h>
50 #include <ctype.h>
51 #include "lp.h"
52 #include "lp.local.h"
53 #include "pathnames.h"
54
55 /*
56 * rmjob - remove the specified jobs from the queue.
57 */
58
59 /*
60 * Stuff for handling lprm specifications
61 */
62 extern char *user[]; /* users to process */
63 extern int users; /* # of users in user array */
64 extern int requ[]; /* job number of spool entries */
65 extern int requests; /* # of spool requests */
66 extern char *person; /* name of person doing lprm */
67
68 static char root[] = "root";
69 static int all = 0; /* eliminate all files (root only) */
70 static int cur_daemon; /* daemon's pid */
71 static char current[40]; /* active control file name */
72
73 extern uid_t uid, euid; /* real and effective user id's */
74
75 static void do_unlink(const char *);
76 static void alarmer(int);
77
78 void
rmjob(void)79 rmjob(void)
80 {
81 int i, nitems;
82 int assasinated = 0;
83 struct dirent **files;
84
85 getprintcap(printer);
86
87 /*
88 * If the format was `lprm -' and the user isn't the super-user,
89 * then fake things to look like he said `lprm user'.
90 */
91 if (users < 0) {
92 if (getuid() == 0)
93 all = 1; /* all files in local queue */
94 else {
95 user[0] = person;
96 users = 1;
97 }
98 }
99 if (!strcmp(person, "-all")) {
100 if (from == host)
101 fatal("The login name \"-all\" is reserved");
102 all = 1; /* all those from 'from' */
103 person = root;
104 }
105
106 seteuid(euid);
107 if (chdir(SD) < 0)
108 fatal("cannot chdir to spool directory");
109 if ((nitems = scandir(".", &files, iscf, NULL)) < 0)
110 fatal("cannot access spool directory");
111 seteuid(uid);
112
113 if (nitems) {
114 /*
115 * Check for an active printer daemon (in which case we
116 * kill it if it is reading our file) then remove stuff
117 * (after which we have to restart the daemon).
118 */
119 if (lockchk(LO) && chk(current)) {
120 seteuid(euid);
121 assasinated = kill(cur_daemon, SIGINT) == 0;
122 seteuid(uid);
123 if (!assasinated)
124 fatal("cannot kill printer daemon");
125 }
126 /*
127 * process the files
128 */
129 for (i = 0; i < nitems; i++)
130 process(files[i]->d_name);
131 }
132 rmremote();
133 /*
134 * Restart the printer daemon if it was killed
135 */
136 if (assasinated && !startdaemon(printer))
137 fatal("cannot restart printer daemon\n");
138 exit(0);
139 }
140
141 /*
142 * Process a lock file: collect the pid of the active
143 * daemon and the file name of the active spool entry.
144 * Return boolean indicating existence of a lock file.
145 */
146 int
lockchk(const char * s)147 lockchk(const char *s)
148 {
149 FILE *fp;
150 int i, n;
151
152 seteuid(euid);
153 if ((fp = fopen(s, "r")) == NULL) {
154 if (errno == EACCES)
155 fatal("can't access lock file");
156 else
157 return(0);
158 }
159 seteuid(uid);
160 if (!get_line(fp)) {
161 (void)fclose(fp);
162 return(0); /* no daemon present */
163 }
164 cur_daemon = atoi(line);
165 if (kill(cur_daemon, 0) < 0 && errno != EPERM) {
166 (void)fclose(fp);
167 return(0); /* no daemon present */
168 }
169 for (i = 1; (n = fread(current, sizeof(char), sizeof(current), fp)) <= 0; i++) {
170 if (i > 5) {
171 n = 1;
172 break;
173 }
174 sleep((size_t)i);
175 }
176 current[n-1] = '\0';
177 (void)fclose(fp);
178 return(1);
179 }
180
181 /*
182 * Process a control file.
183 */
184 void
process(const char * file)185 process(const char *file)
186 {
187 FILE *cfp;
188
189 if (!chk(file))
190 return;
191 seteuid(euid);
192 if ((cfp = fopen(file, "r")) == NULL)
193 fatal("cannot open %s", file);
194 seteuid(uid);
195 while (get_line(cfp)) {
196 switch (line[0]) {
197 case 'U': /* unlink associated files */
198 if (strchr(line+1, '/') || strncmp(line+1, "df", 2))
199 break;
200 do_unlink(line+1);
201 }
202 }
203 (void)fclose(cfp);
204 do_unlink(file);
205 }
206
207 static void
do_unlink(const char * file)208 do_unlink(const char *file)
209 {
210 int ret;
211
212 if (from != host)
213 printf("%s: ", host);
214 seteuid(euid);
215 ret = unlink(file);
216 seteuid(uid);
217 printf(ret ? "cannot dequeue %s\n" : "%s dequeued\n", file);
218 }
219
220 /*
221 * Do the dirty work in checking
222 */
223 int
chk(const char * file)224 chk(const char *file)
225 {
226 int *r, n;
227 char **u;
228 const char *cp;
229 FILE *cfp;
230
231 /*
232 * Check for valid cf file name (mostly checking current).
233 */
234 if (strlen(file) < 7 || file[0] != 'c' || file[1] != 'f')
235 return(0);
236
237 if (all && (from == host || !strcmp(from, file+6)))
238 return(1);
239
240 /*
241 * get the owner's name from the control file.
242 */
243 seteuid(euid);
244 if ((cfp = fopen(file, "r")) == NULL)
245 return(0);
246 seteuid(uid);
247 while (get_line(cfp)) {
248 if (line[0] == 'P')
249 break;
250 }
251 (void)fclose(cfp);
252 if (line[0] != 'P')
253 return(0);
254
255 if (users == 0 && requests == 0)
256 return(!strcmp(file, current) && isowner(line+1, file));
257 /*
258 * Check the request list
259 */
260 for (n = 0, cp = file+3; isdigit((unsigned char)*cp); )
261 n = n * 10 + (*cp++ - '0');
262 for (r = requ; r < &requ[requests]; r++)
263 if (*r == n && isowner(line+1, file))
264 return(1);
265 /*
266 * Check to see if it's in the user list
267 */
268 for (u = user; u < &user[users]; u++)
269 if (!strcmp(*u, line+1) && isowner(line+1, file))
270 return(1);
271 return(0);
272 }
273
274 /*
275 * If root is removing a file on the local machine, allow it.
276 * If root is removing a file from a remote machine, only allow
277 * files sent from the remote machine to be removed.
278 * Normal users can only remove the file from where it was sent.
279 */
280 int
isowner(const char * owner,const char * file)281 isowner(const char *owner, const char *file)
282 {
283 if (!strcmp(person, root) && (from == host || !strcmp(from, file+6)))
284 return(1);
285 if (!strcmp(person, owner) && !strcmp(from, file+6))
286 return(1);
287 if (from != host)
288 printf("%s: ", host);
289 printf("%s: Permission denied\n", file);
290 return(0);
291 }
292
293 /*
294 * Check to see if we are sending files to a remote machine. If we are,
295 * then try removing files on the remote machine.
296 */
297 void
rmremote(void)298 rmremote(void)
299 {
300 char *cp, *s;
301 int i, rem;
302 size_t len;
303
304 if (!remote)
305 return; /* not sending to a remote machine */
306
307 /*
308 * Flush stdout so the user can see what has been deleted
309 * while we wait (possibly) for the connection.
310 */
311 fflush(stdout);
312
313 /* \5 RP space all */
314 len = 1 + strlen(RP) + 1 + strlen(all ? "-all" : person);
315 for (i = 0; i < users; i++) {
316 len += strlen(user[i]) + 1;
317 }
318 for (i = 0; i < requests; i++) {
319 len += snprintf(line, sizeof(line), " %d", requ[i]);
320 }
321 /* newline nul */
322 len += 2;
323 if (len > sizeof(line))
324 s = malloc(len);
325 else
326 s = line;
327 cp = s;
328
329 cp += snprintf(s, len, "\5%s %s", RP, all ? "-all" : person);
330 for (i = 0; i < users; i++) {
331 *cp++ = ' ';
332 strncpy(cp, user[i], len - (cp - s) - 2);
333 cp += strlen(cp);
334 }
335 for (i = 0; i < requests; i++) {
336 (void)snprintf(cp, len - (cp - s) - 1, " %d", requ[i]);
337 cp += strlen(cp);
338 }
339 cp[0] = '\n';
340 cp[1] = '\0';
341
342 rem = getport(RM);
343 if (rem < 0) {
344 if (from != host)
345 printf("%s: ", host);
346 printf("connection to %s is down\n", RM);
347 } else {
348 struct sigaction osa, nsa;
349
350 if ((size_t)write(rem, s, len) != len)
351 fatal("Lost connection");
352 if (len > sizeof(line))
353 (void)free(s);
354 nsa.sa_handler = alarmer;
355 sigemptyset(&nsa.sa_mask);
356 sigaddset(&nsa.sa_mask, SIGALRM);
357 nsa.sa_flags = 0;
358 (void)sigaction(SIGALRM, &nsa, &osa);
359 alarm(wait_time);
360 while ((i = read(rem, line, sizeof(line))) > 0) {
361 (void)fwrite(line, 1, (size_t)i, stdout);
362 alarm(wait_time);
363 }
364 alarm(0);
365 (void)sigaction(SIGALRM, &osa, NULL);
366 (void)close(rem);
367 }
368 }
369
370 static void
alarmer(int s)371 alarmer(int s)
372 {
373 /* nothing */
374 }
375
376 /*
377 * Return 1 if the filename begins with 'cf'
378 */
379 int
iscf(const struct dirent * d)380 iscf(const struct dirent *d)
381 {
382 return(d->d_name[0] == 'c' && d->d_name[1] == 'f');
383 }
384