1/*
2 * Copyright (c) 1983, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if 0
31#ifndef lint
32static char sccsid[] = "@(#)rmjob.c	8.2 (Berkeley) 4/28/95";
33#endif /* not lint */
34#endif
35
36#include "lp.cdefs.h"		/* A cross-platform version of <sys/cdefs.h> */
37__FBSDID("$FreeBSD$");
38
39#include <sys/param.h>
40#include <sys/uio.h>
41
42#include <ctype.h>
43#include <dirent.h>
44#include <errno.h>
45#include <signal.h>
46#include <stdio.h>
47#include <stdlib.h>
48#include <string.h>
49#define psignal foil_gcc_psignal
50#define	sys_siglist foil_gcc_siglist
51#include <unistd.h>
52#undef psignal
53#undef sys_siglist
54
55#include "lp.h"
56#include "lp.local.h"
57#include "pathnames.h"
58
59/*
60 * rmjob - remove the specified jobs from the queue.
61 */
62
63/*
64 * Stuff for handling lprm specifications
65 */
66static char	root[] = "root";
67static int	all = 0;		/* eliminate all files (root only) */
68static int	cur_daemon;		/* daemon's pid */
69static char	current[7+MAXHOSTNAMELEN];  /* active control file name */
70
71extern uid_t	uid, euid;		/* real and effective user id's */
72
73static	void	alarmhandler(int _signo);
74static	void	do_unlink(char *_file);
75static int	 isowner(char *_owner, char *_file, const char *_cfhost);
76
77void
78rmjob(const char *printer)
79{
80	register int i, nitems;
81	int assasinated = 0;
82	struct dirent **files;
83	char *cp;
84	struct printer myprinter, *pp = &myprinter;
85
86	init_printer(pp);
87	if ((i = getprintcap(printer, pp)) < 0)
88		fatal(pp, "getprintcap: %s", pcaperr(i));
89	if ((cp = checkremote(pp))) {
90		printf("Warning: %s\n", cp);
91		free(cp);
92	}
93
94	/*
95	 * If the format was `lprm -' and the user isn't the super-user,
96	 *  then fake things to look like he said `lprm user'.
97	 */
98	if (users < 0) {
99		if (getuid() == 0)
100			all = 1;	/* all files in local queue */
101		else {
102			user[0] = person;
103			users = 1;
104		}
105	}
106	if (!strcmp(person, "-all")) {
107		if (from_host == local_host)
108			fatal(pp, "The login name \"-all\" is reserved");
109		all = 1;	/* all those from 'from_host' */
110		person = root;
111	}
112
113	seteuid(euid);
114	if (chdir(pp->spool_dir) < 0)
115		fatal(pp, "cannot chdir to spool directory");
116	if ((nitems = scandir(".", &files, iscf, NULL)) < 0)
117		fatal(pp, "cannot access spool directory");
118	seteuid(uid);
119
120	if (nitems) {
121		/*
122		 * Check for an active printer daemon (in which case we
123		 *  kill it if it is reading our file) then remove stuff
124		 *  (after which we have to restart the daemon).
125		 */
126		if (lockchk(pp, pp->lock_file) && chk(current)) {
127			seteuid(euid);
128			assasinated = kill(cur_daemon, SIGINT) == 0;
129			seteuid(uid);
130			if (!assasinated)
131				fatal(pp, "cannot kill printer daemon");
132		}
133		/*
134		 * process the files
135		 */
136		for (i = 0; i < nitems; i++)
137			process(pp, files[i]->d_name);
138	}
139	rmremote(pp);
140	/*
141	 * Restart the printer daemon if it was killed
142	 */
143	if (assasinated && !startdaemon(pp))
144		fatal(pp, "cannot restart printer daemon\n");
145	exit(0);
146}
147
148/*
149 * Process a lock file: collect the pid of the active
150 *  daemon and the file name of the active spool entry.
151 * Return boolean indicating existence of a lock file.
152 */
153int
154lockchk(struct printer *pp, char *slockf)
155{
156	register FILE *fp;
157	register int i, n;
158
159	seteuid(euid);
160	if ((fp = fopen(slockf, "r")) == NULL) {
161		if (errno == EACCES)
162			fatal(pp, "%s: %s", slockf, strerror(errno));
163		else
164			return(0);
165	}
166	seteuid(uid);
167	if (!getline(fp)) {
168		(void) fclose(fp);
169		return(0);		/* no daemon present */
170	}
171	cur_daemon = atoi(line);
172	if (kill(cur_daemon, 0) < 0 && errno != EPERM) {
173		(void) fclose(fp);
174		return(0);		/* no daemon present */
175	}
176	for (i = 1; (n = fread(current, sizeof(char), sizeof(current), fp)) <= 0; i++) {
177		if (i > 5) {
178			n = 1;
179			break;
180		}
181		sleep(i);
182	}
183	current[n-1] = '\0';
184	(void) fclose(fp);
185	return(1);
186}
187
188/*
189 * Process a control file.
190 */
191void
192process(const struct printer *pp, char *file)
193{
194	FILE *cfp;
195
196	if (!chk(file))
197		return;
198	seteuid(euid);
199	if ((cfp = fopen(file, "r")) == NULL)
200		fatal(pp, "cannot open %s", file);
201	seteuid(uid);
202	while (getline(cfp)) {
203		switch (line[0]) {
204		case 'U':  /* unlink associated files */
205			if (strchr(line+1, '/') || strncmp(line+1, "df", 2))
206				break;
207			do_unlink(line+1);
208		}
209	}
210	(void) fclose(cfp);
211	do_unlink(file);
212}
213
214static void
215do_unlink(char *file)
216{
217	int	ret;
218
219	if (from_host != local_host)
220		printf("%s: ", local_host);
221	seteuid(euid);
222	ret = unlink(file);
223	seteuid(uid);
224	printf(ret ? "cannot dequeue %s\n" : "%s dequeued\n", file);
225}
226
227/*
228 * Do the dirty work in checking
229 */
230int
231chk(char *file)
232{
233	int *r, jnum;
234	char **u;
235	const char *cfhost;
236	FILE *cfp;
237
238	/*
239	 * Check for valid cf file name (mostly checking current).
240	 */
241	if (strlen(file) < 7 || file[0] != 'c' || file[1] != 'f')
242		return(0);
243
244	jnum = calc_jobnum(file, &cfhost);
245	if (all && (from_host == local_host || !strcmp(from_host, cfhost)))
246		return(1);
247
248	/*
249	 * get the owner's name from the control file.
250	 */
251	seteuid(euid);
252	if ((cfp = fopen(file, "r")) == NULL)
253		return(0);
254	seteuid(uid);
255	while (getline(cfp)) {
256		if (line[0] == 'P')
257			break;
258	}
259	(void) fclose(cfp);
260	if (line[0] != 'P')
261		return(0);
262
263	if (users == 0 && requests == 0)
264		return(!strcmp(file, current) && isowner(line+1, file, cfhost));
265	/*
266	 * Check the request list
267	 */
268	for (r = requ; r < &requ[requests]; r++)
269		if (*r == jnum && isowner(line+1, file, cfhost))
270			return(1);
271	/*
272	 * Check to see if it's in the user list
273	 */
274	for (u = user; u < &user[users]; u++)
275		if (!strcmp(*u, line+1) && isowner(line+1, file, cfhost))
276			return(1);
277	return(0);
278}
279
280/*
281 * If root is removing a file on the local machine, allow it.
282 * If root is removing a file from a remote machine, only allow
283 * files sent from the remote machine to be removed.
284 * Normal users can only remove the file from where it was sent.
285 */
286static int
287isowner(char *owner, char *file, const char *cfhost)
288{
289	if (!strcmp(person, root) && (from_host == local_host ||
290	    !strcmp(from_host, cfhost)))
291		return (1);
292	if (!strcmp(person, owner) && !strcmp(from_host, cfhost))
293		return (1);
294	if (from_host != local_host)
295		printf("%s: ", local_host);
296	printf("%s: Permission denied\n", file);
297	return(0);
298}
299
300/*
301 * Check to see if we are sending files to a remote machine. If we are,
302 * then try removing files on the remote machine.
303 */
304void
305rmremote(const struct printer *pp)
306{
307	int i, elem, firstreq, niov, rem, totlen;
308	char buf[BUFSIZ];
309	void (*savealrm)(int);
310	struct iovec *iov;
311
312	if (!pp->remote)
313		return;	/* not sending to a remote machine */
314
315	/*
316	 * Flush stdout so the user can see what has been deleted
317	 * while we wait (possibly) for the connection.
318	 */
319	fflush(stdout);
320
321	/*
322	 * Counting:
323	 *	4 == "\5" + remote_queue + " " + person
324	 *	2 * users == " " + user[i] for each user
325	 *	requests == asprintf results for each request
326	 *	1 == "\n"
327	 * Although laborious, doing it this way makes it possible for
328	 * us to process requests of indeterminate length without
329	 * applying an arbitrary limit.  Arbitrary Limits Are Bad (tm).
330	 */
331	if (users > 0)
332		niov = 4 + 2 * users + requests + 1;
333	else
334		niov = 4 + requests + 1;
335	iov = malloc(niov * sizeof *iov);
336	if (iov == 0)
337		fatal(pp, "out of memory in rmremote()");
338	iov[0].iov_base = "\5";
339	iov[1].iov_base = pp->remote_queue;
340	iov[2].iov_base = " ";
341	iov[3].iov_base = all ? "-all" : person;
342	elem = 4;
343	for (i = 0; i < users; i++) {
344		iov[elem].iov_base = " ";
345		iov[elem + 1].iov_base = user[i];
346		elem += 2;
347	}
348	firstreq = elem;
349	for (i = 0; i < requests; i++) {
350		asprintf((char **)&iov[elem].iov_base, " %d", requ[i]);
351		if (iov[elem].iov_base == 0)
352			fatal(pp, "out of memory in rmremote()");
353		elem++;
354	}
355	iov[elem++].iov_base = "\n";
356	for (totlen = i = 0; i < niov; i++)
357		totlen += (iov[i].iov_len = strlen(iov[i].iov_base));
358
359	savealrm = signal(SIGALRM, alarmhandler);
360	alarm(pp->conn_timeout);
361	rem = getport(pp, pp->remote_host, 0);
362	(void)signal(SIGALRM, savealrm);
363	if (rem < 0) {
364		if (from_host != local_host)
365			printf("%s: ", local_host);
366		printf("connection to %s is down\n", pp->remote_host);
367	} else {
368		if (writev(rem, iov, niov) != totlen)
369			fatal(pp, "Lost connection");
370		while ((i = read(rem, buf, sizeof(buf))) > 0)
371			(void) fwrite(buf, 1, i, stdout);
372		(void) close(rem);
373	}
374	for (i = 0; i < requests; i++)
375		free(iov[firstreq + i].iov_base);
376	free(iov);
377}
378
379/*
380 * Return 1 if the filename begins with 'cf'
381 */
382int
383iscf(const struct dirent *d)
384{
385	return(d->d_name[0] == 'c' && d->d_name[1] == 'f');
386}
387
388void
389alarmhandler(int signo __unused)
390{
391	/* the signal is ignored */
392	/* (the '__unused' is just to avoid a compile-time warning) */
393}
394