recvjob.c revision 182599 
1/*
2 * Copyright (c) 1983, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. All advertising materials mentioning features or use of this software
15 *    must display the following acknowledgement:
16 *	This product includes software developed by the University of
17 *	California, Berkeley and its contributors.
18 * 4. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#ifndef lint
36static const char copyright[] =
37"@(#) Copyright (c) 1983, 1993\n\
38	The Regents of the University of California.  All rights reserved.\n";
39#endif /* not lint */
40
41#if 0
42#ifndef lint
43static char sccsid[] = "@(#)recvjob.c	8.2 (Berkeley) 4/27/95";
44#endif /* not lint */
45#endif
46
47#include "lp.cdefs.h"		/* A cross-platform version of <sys/cdefs.h> */
48__FBSDID("$FreeBSD: head/usr.sbin/lpr/lpd/recvjob.c 182599 2008-09-01 12:32:40Z ticso $");
49
50/*
51 * Receive printer jobs from the network, queue them and
52 * start the printer daemon.
53 */
54#include <sys/param.h>
55#include <sys/mount.h>
56#include <sys/stat.h>
57
58#include <unistd.h>
59#include <signal.h>
60#include <fcntl.h>
61#include <dirent.h>
62#include <errno.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 "ctlinfo.h"
70#include "extern.h"
71#include "pathnames.h"
72
73#define ack()	(void) write(STDOUT_FILENO, sp, (size_t)1);
74
75/*
76 * The buffer size to use when reading/writing spool files.
77 */
78#define	SPL_BUFSIZ	BUFSIZ
79
80static char	 dfname[NAME_MAX];	/* data files */
81static int	 minfree;       /* keep at least minfree blocks available */
82static const char	*sp = "";
83static char	 tfname[NAME_MAX];	/* tmp copy of cf before linking */
84
85static int	 chksize(int _size);
86static void	 frecverr(const char *_msg, ...) __printf0like(1, 2);
87static int	 noresponse(void);
88static void	 rcleanup(int _signo);
89static int	 read_number(const char *_fn);
90static int	 readfile(struct printer *_pp, char *_file, size_t _size);
91static int	 readjob(struct printer *_pp);
92
93
94void
95recvjob(const char *printer)
96{
97	struct stat stb;
98	int status;
99	struct printer myprinter, *pp = &myprinter;
100
101	/*
102	 * Perform lookup for printer name or abbreviation
103	 */
104	init_printer(pp);
105	status = getprintcap(printer, pp);
106	switch (status) {
107	case PCAPERR_OSERR:
108		frecverr("cannot open printer description file");
109		break;
110	case PCAPERR_NOTFOUND:
111		frecverr("unknown printer %s", printer);
112		break;
113	case PCAPERR_TCLOOP:
114		fatal(pp, "potential reference loop detected in printcap file");
115	default:
116		break;
117	}
118
119	(void) close(STDERR_FILENO);			/* set up log file */
120	if (open(pp->log_file, O_WRONLY|O_APPEND, 0664) < 0) {
121		syslog(LOG_ERR, "%s: %m", pp->log_file);
122		(void) open(_PATH_DEVNULL, O_WRONLY);
123	}
124
125	if (chdir(pp->spool_dir) < 0)
126		frecverr("%s: chdir(%s): %s", pp->printer, pp->spool_dir,
127		    strerror(errno));
128	if (stat(pp->lock_file, &stb) == 0) {
129		if (stb.st_mode & 010) {
130			/* queue is disabled */
131			putchar('\1');		/* return error code */
132			exit(1);
133		}
134	} else if (stat(pp->spool_dir, &stb) < 0)
135		frecverr("%s: stat(%s): %s", pp->printer, pp->spool_dir,
136		    strerror(errno));
137	minfree = 2 * read_number("minfree");	/* scale KB to 512 blocks */
138	signal(SIGTERM, rcleanup);
139	signal(SIGPIPE, rcleanup);
140
141	if (readjob(pp))
142		printjob(pp);
143}
144
145/*
146 * Read printer jobs sent by lpd and copy them to the spooling directory.
147 * Return the number of jobs successfully transfered.
148 */
149static int
150readjob(struct printer *pp)
151{
152	register int size;
153	int cfcnt, dfcnt;
154	char *cp, *clastp, *errmsg;
155	char givenid[32], givenhost[MAXHOSTNAMELEN];
156
157	ack();
158	cfcnt = 0;
159	dfcnt = 0;
160	for (;;) {
161		/*
162		 * Read a command to tell us what to do
163		 */
164		cp = line;
165		clastp = line + sizeof(line) - 1;
166		do {
167			size = read(STDOUT_FILENO, cp, (size_t)1);
168			if (size != (ssize_t)1) {
169				if (size < (ssize_t)0) {
170					frecverr("%s: lost connection",
171					    pp->printer);
172					/*NOTREACHED*/
173				}
174				return (cfcnt);
175			}
176		} while ((*cp++ != '\n') && (cp <= clastp));
177		if (cp > clastp) {
178			frecverr("%s: readjob overflow", pp->printer);
179			/*NOTREACHED*/
180		}
181		*--cp = '\0';
182		cp = line;
183		switch (*cp++) {
184		case '\1':	/* cleanup because data sent was bad */
185			rcleanup(0);
186			continue;
187
188		case '\2':	/* read cf file */
189			size = 0;
190			dfcnt = 0;
191			while (*cp >= '0' && *cp <= '9')
192				size = size * 10 + (*cp++ - '0');
193			if (*cp++ != ' ')
194				break;
195			/*
196			 * host name has been authenticated, we use our
197			 * view of the host name since we may be passed
198			 * something different than what gethostbyaddr()
199			 * returns
200			 */
201			strlcpy(cp + 6, from_host, sizeof(line)
202			    + (size_t)(line - cp - 6));
203			if (strchr(cp, '/')) {
204				frecverr("readjob: %s: illegal path name", cp);
205				/*NOTREACHED*/
206			}
207			strlcpy(tfname, cp, sizeof(tfname));
208			tfname[sizeof (tfname) - 1] = '\0';
209			tfname[0] = 't';
210			if (!chksize(size)) {
211				(void) write(STDOUT_FILENO, "\2", (size_t)1);
212				continue;
213			}
214			if (!readfile(pp, tfname, (size_t)size)) {
215				rcleanup(0);
216				continue;
217			}
218			errmsg = ctl_renametf(pp->printer, tfname);
219			tfname[0] = '\0';
220			if (errmsg != NULL) {
221				frecverr("%s: %s", pp->printer, errmsg);
222				/*NOTREACHED*/
223			}
224			cfcnt++;
225			continue;
226
227		case '\3':	/* read df file */
228			*givenid = '\0';
229			*givenhost = '\0';
230			size = 0;
231			while (*cp >= '0' && *cp <= '9')
232				size = size * 10 + (*cp++ - '0');
233			if (*cp++ != ' ')
234				break;
235			if (strchr(cp, '/')) {
236				frecverr("readjob: %s: illegal path name", cp);
237				/*NOTREACHED*/
238			}
239			if (!chksize(size)) {
240				(void) write(STDOUT_FILENO, "\2", (size_t)1);
241				continue;
242			}
243			strlcpy(dfname, cp, sizeof(dfname));
244			dfcnt++;
245			trstat_init(pp, dfname, dfcnt);
246			(void) readfile(pp, dfname, (size_t)size);
247			trstat_write(pp, TR_RECVING, (size_t)size, givenid,
248			    from_host, givenhost);
249			continue;
250		}
251		frecverr("protocol screwup: %s", line);
252		/*NOTREACHED*/
253	}
254}
255
256/*
257 * Read files send by lpd and copy them to the spooling directory.
258 */
259static int
260readfile(struct printer *pp, char *file, size_t size)
261{
262	register char *cp;
263	char buf[SPL_BUFSIZ];
264	size_t amt, i;
265	int err, fd, j;
266
267	fd = open(file, O_CREAT|O_EXCL|O_WRONLY, FILMOD);
268	if (fd < 0) {
269		frecverr("%s: readfile: error on open(%s): %s",
270			 pp->printer, file, strerror(errno));
271		/*NOTREACHED*/
272	}
273	ack();
274	err = 0;
275	for (i = 0; i < size; i += SPL_BUFSIZ) {
276		amt = SPL_BUFSIZ;
277		cp = buf;
278		if (i + amt > size)
279			amt = size - i;
280		do {
281			j = read(STDOUT_FILENO, cp, amt);
282			if (j <= 0) {
283				frecverr("%s: lost connection", pp->printer);
284				/*NOTREACHED*/
285			}
286			amt -= j;
287			cp += j;
288		} while (amt > 0);
289		amt = SPL_BUFSIZ;
290		if (i + amt > size)
291			amt = size - i;
292		if (write(fd, buf, amt) != (ssize_t)amt) {
293			err++;
294			break;
295		}
296	}
297	(void) close(fd);
298	if (err) {
299		frecverr("%s: write error on close(%s)", pp->printer, file);
300		/*NOTREACHED*/
301	}
302	if (noresponse()) {		/* file sent had bad data in it */
303		if (strchr(file, '/') == NULL)
304			(void) unlink(file);
305		return (0);
306	}
307	ack();
308	return (1);
309}
310
311static int
312noresponse(void)
313{
314	char resp;
315
316	if (read(STDOUT_FILENO, &resp, (size_t)1) != 1) {
317		frecverr("lost connection in noresponse()");
318		/*NOTREACHED*/
319	}
320	if (resp == '\0')
321		return(0);
322	return(1);
323}
324
325/*
326 * Check to see if there is enough space on the disk for size bytes.
327 * 1 == OK, 0 == Not OK.
328 */
329static int
330chksize(int size)
331{
332	int64_t spacefree;
333	struct statfs sfb;
334
335	if (statfs(".", &sfb) < 0) {
336		syslog(LOG_ERR, "%s: %m", "statfs(\".\")");
337		return (1);
338	}
339	spacefree = sfb.f_bavail * (sfb.f_bsize / 512);
340	size = (size + 511) / 512;
341	if (minfree + size > spacefree)
342		return(0);
343	return(1);
344}
345
346static int
347read_number(const char *fn)
348{
349	char lin[80];
350	register FILE *fp;
351
352	if ((fp = fopen(fn, "r")) == NULL)
353		return (0);
354	if (fgets(lin, sizeof(lin), fp) == NULL) {
355		fclose(fp);
356		return (0);
357	}
358	fclose(fp);
359	return (atoi(lin));
360}
361
362/*
363 * Remove all the files associated with the current job being transfered.
364 */
365static void
366rcleanup(int signo __unused)
367{
368	if (tfname[0] && strchr(tfname, '/') == NULL)
369		(void) unlink(tfname);
370	if (dfname[0] && strchr(dfname, '/') == NULL) {
371		do {
372			do
373				(void) unlink(dfname);
374			while (dfname[2]-- != 'A');
375			dfname[2] = 'z';
376		} while (dfname[0]-- != 'd');
377	}
378	dfname[0] = '\0';
379}
380
381#include <stdarg.h>
382
383static void
384frecverr(const char *msg, ...)
385{
386	va_list ap;
387	va_start(ap, msg);
388	syslog(LOG_ERR, "Error receiving job from %s:", from_host);
389	vsyslog(LOG_ERR, msg, ap);
390	va_end(ap);
391	/*
392	 * rcleanup is not called until AFTER logging the error message,
393	 * because rcleanup will zap some variables which may have been
394	 * supplied as parameters for that msg...
395	 */
396	rcleanup(0);
397	/*
398	 * Add a minimal delay before returning the final error code to
399	 * the sending host.  This just in case that machine responds
400	 * this error by INSTANTLY retrying (and instantly re-failing...).
401	 * It would be stupid of the sending host to do that, but if there
402	 * was a broken implementation which did it, the result might be
403	 * obscure performance problems and a flood of syslog messages on
404	 * the receiving host.
405	 */
406	sleep(2);		/* a paranoid throttling measure */
407	putchar('\1');		/* return error code */
408	exit(1);
409}
410