recvjob.c revision 1.10 
1/*	$OpenBSD: recvjob.c,v 1.10 1997/07/20 19:04:18 deraadt Exp $	*/
2
3/*
4 * Copyright (c) 1983, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
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 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#ifndef lint
38static char copyright[] =
39"@(#) Copyright (c) 1983, 1993\n\
40	The Regents of the University of California.  All rights reserved.\n";
41#endif /* not lint */
42
43#ifndef lint
44#if 0
45static char sccsid[] = "@(#)recvjob.c	8.2 (Berkeley) 4/27/95";
46#else
47static char rcsid[] = "$OpenBSD: recvjob.c,v 1.10 1997/07/20 19:04:18 deraadt Exp $";
48#endif
49#endif /* not lint */
50
51/*
52 * Receive printer jobs from the network, queue them and
53 * start the printer daemon.
54 */
55#include <sys/param.h>
56#include <sys/mount.h>
57#include <sys/stat.h>
58
59#include <unistd.h>
60#include <signal.h>
61#include <fcntl.h>
62#include <dirent.h>
63#include <syslog.h>
64#include <stdio.h>
65#include <stdlib.h>
66#include <string.h>
67#include "lp.h"
68#include "lp.local.h"
69#include "extern.h"
70#include "pathnames.h"
71
72#define ack()	(void) write(1, sp, 1);
73
74static char	 dfname[NAME_MAX];	/* data files */
75static int	 minfree;       /* keep at least minfree blocks available */
76static char	*sp = "";
77static char	 tfname[NAME_MAX];	/* tmp copy of cf before linking */
78
79static int        chksize __P((int));
80static void       frecverr __P((const char *, ...));
81static int        noresponse __P((void));
82static void       rcleanup __P((int));
83static int        read_number __P((char *));
84static int        readfile __P((char *, int));
85static int        readjob __P((void));
86
87
88void
89recvjob()
90{
91	struct stat stb;
92	int status;
93
94	/*
95	 * Perform lookup for printer name or abbreviation
96	 */
97	if ((status = cgetent(&bp, printcapdb, printer)) == -2)
98		frecverr("cannot open printer description file");
99	else if (status == -1)
100		frecverr("unknown printer %s", printer);
101	else if (status == -3)
102		fatal("potential reference loop detected in printcap file");
103
104	if (cgetstr(bp, "lf", &LF) == -1)
105		LF = _PATH_CONSOLE;
106	if (cgetstr(bp, "sd", &SD) == -1)
107		SD = _PATH_DEFSPOOL;
108	if (cgetstr(bp, "lo", &LO) == -1)
109		LO = DEFLOCK;
110
111	(void) close(2);			/* set up log file */
112	if (open(LF, O_WRONLY|O_APPEND, 0664) < 0) {
113		syslog(LOG_ERR, "%s: %m", LF);
114		(void) open(_PATH_DEVNULL, O_WRONLY);
115	}
116
117	if (chdir(SD) < 0)
118		frecverr("%s: %s: %m", printer, SD);
119	if (stat(LO, &stb) == 0) {
120		if (stb.st_mode & 010) {
121			/* queue is disabled */
122			putchar('\1');		/* return error code */
123			exit(1);
124		}
125	} else if (stat(SD, &stb) < 0)
126		frecverr("%s: %s: %m", printer, SD);
127	minfree = 2 * read_number("minfree");	/* scale KB to 512 blocks */
128	signal(SIGTERM, rcleanup);
129	signal(SIGPIPE, rcleanup);
130
131	if (readjob())
132		printjob();
133}
134
135/*
136 * Read printer jobs sent by lpd and copy them to the spooling directory.
137 * Return the number of jobs successfully transfered.
138 */
139static int
140readjob()
141{
142	register int size, nfiles;
143	register char *cp;
144
145	ack();
146	nfiles = 0;
147	for (;;) {
148		/*
149		 * Read a command to tell us what to do
150		 */
151		cp = line;
152		do {
153			if ((size = read(1, cp, 1)) != 1) {
154				if (size < 0)
155					frecverr("%s: Lost connection",
156					    printer);
157				return(nfiles);
158			}
159		} while (*cp++ != '\n' && (cp - line + 1) < sizeof line);
160		if (cp - line + 1 >= sizeof line)
161			frecverr("readjob overflow");
162		*--cp = '\0';
163		cp = line;
164		switch (*cp++) {
165		case '\1':	/* cleanup because data sent was bad */
166			rcleanup(0);
167			continue;
168
169		case '\2':	/* read cf file */
170			size = 0;
171			while (*cp >= '0' && *cp <= '9')
172				size = size * 10 + (*cp++ - '0');
173			if (*cp++ != ' ')
174				break;
175			/*
176			 * host name has been authenticated, we use our
177			 * view of the host name since we may be passed
178			 * something different than what gethostbyaddr()
179			 * returns
180			 */
181			strncpy(cp + 6, from, sizeof(line) + line - cp - 7);
182			line[sizeof(line) -1 ] = '\0';
183			strncpy(tfname, cp, sizeof tfname-1);
184			tfname[sizeof tfname-1] = '\0';
185			tfname[0] = 't';
186			if (strchr(tfname, '/'))
187				frecverr("readjob: %s: illegal path name",
188				    tfname);
189			if (!chksize(size)) {
190				(void) write(1, "\2", 1);
191				continue;
192			}
193			if (!readfile(tfname, size)) {
194				rcleanup(0);
195				continue;
196			}
197			if (link(tfname, cp) < 0)
198				frecverr("%s: %m", tfname);
199			(void) unlink(tfname);
200			tfname[0] = '\0';
201			nfiles++;
202			continue;
203
204		case '\3':	/* read df file */
205			size = 0;
206			while (*cp >= '0' && *cp <= '9')
207				size = size * 10 + (*cp++ - '0');
208			if (*cp++ != ' ')
209				break;
210			if (!chksize(size)) {
211				(void) write(1, "\2", 1);
212				continue;
213			}
214			(void) strncpy(dfname, cp, sizeof dfname-1);
215			dfname[sizeof dfname-1] = '\0';
216			if (strchr(dfname, '/'))
217				frecverr("readjob: %s: illegal path name",
218					dfname);
219			(void) readfile(dfname, size);
220			continue;
221		}
222		frecverr("protocol screwup: %s", line);
223	}
224}
225
226/*
227 * Read files send by lpd and copy them to the spooling directory.
228 */
229static int
230readfile(file, size)
231	char *file;
232	int size;
233{
234	register char *cp;
235	char buf[BUFSIZ];
236	register int i, j, amt;
237	int fd, err;
238
239	fd = open(file, O_CREAT|O_EXCL|O_WRONLY, FILMOD);
240	if (fd < 0)
241		frecverr("readfile: %s: illegal path name: %m", file);
242	ack();
243	err = 0;
244	for (i = 0; i < size; i += BUFSIZ) {
245		amt = BUFSIZ;
246		cp = buf;
247		if (i + amt > size)
248			amt = size - i;
249		do {
250			j = read(1, cp, amt);
251			if (j <= 0)
252				frecverr("Lost connection");
253			amt -= j;
254			cp += j;
255		} while (amt > 0);
256		amt = BUFSIZ;
257		if (i + amt > size)
258			amt = size - i;
259		if (write(fd, buf, amt) != amt) {
260			err++;
261			break;
262		}
263	}
264	(void) close(fd);
265	if (err)
266		frecverr("%s: write error", file);
267	if (noresponse()) {		/* file sent had bad data in it */
268		(void) unlink(file);
269		return(0);
270	}
271	ack();
272	return(1);
273}
274
275static int
276noresponse()
277{
278	char resp;
279
280	if (read(1, &resp, 1) != 1)
281		frecverr("Lost connection");
282	if (resp == '\0')
283		return(0);
284	return(1);
285}
286
287/*
288 * Check to see if there is enough space on the disk for size bytes.
289 * 1 == OK, 0 == Not OK.
290 */
291static int
292chksize(size)
293	int size;
294{
295	int spacefree;
296	struct statfs sfb;
297
298	if (statfs(".", &sfb) < 0) {
299		syslog(LOG_ERR, "%s: %m", "statfs(\".\")");
300		return (1);
301	}
302	spacefree = sfb.f_bavail * (sfb.f_bsize / 512);
303	size = (size + 511) / 512;
304	if (minfree + size > spacefree)
305		return(0);
306	return(1);
307}
308
309static int
310read_number(fn)
311	char *fn;
312{
313	char lin[80];
314	register FILE *fp;
315
316	if ((fp = fopen(fn, "r")) == NULL)
317		return (0);
318	if (fgets(lin, 80, fp) == NULL) {
319		fclose(fp);
320		return (0);
321	}
322	fclose(fp);
323	return (atoi(lin));
324}
325
326/*
327 * Remove all the files associated with the current job being transfered.
328 */
329static void
330rcleanup(signo)
331	int signo;
332{
333	if (tfname[0])
334		(void) unlink(tfname);
335	if (dfname[0])
336		do {
337			do
338				(void) unlink(dfname);
339			while (dfname[2]-- != 'A');
340			dfname[2] = 'z';
341		} while (dfname[0]-- != 'd');
342	dfname[0] = '\0';
343}
344
345#if __STDC__
346#include <stdarg.h>
347#else
348#include <varargs.h>
349#endif
350
351static void
352#if __STDC__
353frecverr(const char *msg, ...)
354#else
355frecverr(msg, va_alist)
356	char *msg;
357        va_dcl
358#endif
359{
360	extern char fromb[];
361	va_list ap;
362#if __STDC__
363	va_start(ap, msg);
364#else
365	va_start(ap);
366#endif
367	rcleanup(0);
368	syslog(LOG_ERR, "%s", fromb);
369	vsyslog(LOG_ERR, msg, ap);
370	va_end(ap);
371	putchar('\1');		/* return error code */
372	exit(1);
373}
374