recvjob.c revision 117554 
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
42static char sccsid[] = "@(#)recvjob.c	8.2 (Berkeley) 4/27/95";
43#endif
44
45#include "lp.cdefs.h"		/* A cross-platform version of <sys/cdefs.h> */
46__FBSDID("$FreeBSD: head/usr.sbin/lpr/lpd/recvjob.c 117554 2003-07-14 15:54:41Z gad $");
47
48/*
49 * Receive printer jobs from the network, queue them and
50 * start the printer daemon.
51 */
52#include <sys/param.h>
53#include <sys/mount.h>
54#include <sys/stat.h>
55
56#include <unistd.h>
57#include <signal.h>
58#include <fcntl.h>
59#include <dirent.h>
60#include <errno.h>
61#include <syslog.h>
62#include <stdio.h>
63#include <stdlib.h>
64#include <string.h>
65#include "lp.h"
66#include "lp.local.h"
67#include "ctlinfo.h"
68#include "extern.h"
69#include "pathnames.h"
70
71#define ack()	(void) write(STDOUT_FILENO, sp, (size_t)1);
72
73static char	 dfname[NAME_MAX];	/* data files */
74static int	 minfree;       /* keep at least minfree blocks available */
75static const char	*sp = "";
76static char	 tfname[NAME_MAX];	/* tmp copy of cf before linking */
77
78static int	 chksize(int _size);
79static void	 frecverr(const char *_msg, ...) __printf0like(1, 2);
80static int	 noresponse(void);
81static void	 rcleanup(int _signo);
82static int	 read_number(const char *_fn);
83static int	 readfile(struct printer *_pp, char *_file, size_t _size);
84static int	 readjob(struct printer *_pp);
85
86
87void
88recvjob(const char *printer)
89{
90	struct stat stb;
91	int status;
92	struct printer myprinter, *pp = &myprinter;
93
94	/*
95	 * Perform lookup for printer name or abbreviation
96	 */
97	init_printer(pp);
98	status = getprintcap(printer, pp);
99	switch (status) {
100	case PCAPERR_OSERR:
101		frecverr("cannot open printer description file");
102		break;
103	case PCAPERR_NOTFOUND:
104		frecverr("unknown printer %s", printer);
105		break;
106	case PCAPERR_TCLOOP:
107		fatal(pp, "potential reference loop detected in printcap file");
108	default:
109		break;
110	}
111
112	(void) close(2);			/* set up log file */
113	if (open(pp->log_file, O_WRONLY|O_APPEND, 0664) < 0) {
114		syslog(LOG_ERR, "%s: %m", pp->log_file);
115		(void) open(_PATH_DEVNULL, O_WRONLY);
116	}
117
118	if (chdir(pp->spool_dir) < 0)
119		frecverr("%s: chdir(%s): %s", pp->printer, pp->spool_dir,
120		    strerror(errno));
121	if (stat(pp->lock_file, &stb) == 0) {
122		if (stb.st_mode & 010) {
123			/* queue is disabled */
124			putchar('\1');		/* return error code */
125			exit(1);
126		}
127	} else if (stat(pp->spool_dir, &stb) < 0)
128		frecverr("%s: stat(%s): %s", pp->printer, pp->spool_dir,
129		    strerror(errno));
130	minfree = 2 * read_number("minfree");	/* scale KB to 512 blocks */
131	signal(SIGTERM, rcleanup);
132	signal(SIGPIPE, rcleanup);
133
134	if (readjob(pp))
135		printjob(pp);
136}
137
138/*
139 * Read printer jobs sent by lpd and copy them to the spooling directory.
140 * Return the number of jobs successfully transfered.
141 */
142static int
143readjob(struct printer *pp)
144{
145	register int size;
146	int cfcnt, dfcnt;
147	char *cp, *clastp, *errmsg;
148	char givenid[32], givenhost[MAXHOSTNAMELEN];
149
150	ack();
151	cfcnt = 0;
152	dfcnt = 0;
153	for (;;) {
154		/*
155		 * Read a command to tell us what to do
156		 */
157		cp = line;
158		clastp = line + sizeof(line) - 1;
159		do {
160			size = read(STDOUT_FILENO, cp, (size_t)1);
161			if (size != (ssize_t)1) {
162				if (size < (ssize_t)0) {
163					frecverr("%s: lost connection",
164					    pp->printer);
165					/*NOTREACHED*/
166				}
167				return (cfcnt);
168			}
169		} while ((*cp++ != '\n') && (cp <= clastp));
170		if (cp > clastp) {
171			frecverr("%s: readjob overflow", pp->printer);
172			/*NOTREACHED*/
173		}
174		*--cp = '\0';
175		cp = line;
176		switch (*cp++) {
177		case '\1':	/* cleanup because data sent was bad */
178			rcleanup(0);
179			continue;
180
181		case '\2':	/* read cf file */
182			size = 0;
183			dfcnt = 0;
184			while (*cp >= '0' && *cp <= '9')
185				size = size * 10 + (*cp++ - '0');
186			if (*cp++ != ' ')
187				break;
188			/*
189			 * host name has been authenticated, we use our
190			 * view of the host name since we may be passed
191			 * something different than what gethostbyaddr()
192			 * returns
193			 */
194			strlcpy(cp + 6, from_host, sizeof(line)
195			    + (size_t)(line - cp - 6));
196			if (strchr(cp, '/')) {
197				frecverr("readjob: %s: illegal path name", cp);
198				/*NOTREACHED*/
199			}
200			strlcpy(tfname, cp, sizeof(tfname));
201			tfname[sizeof (tfname) - 1] = '\0';
202			tfname[0] = 't';
203			if (!chksize(size)) {
204				(void) write(STDOUT_FILENO, "\2", (size_t)1);
205				continue;
206			}
207			if (!readfile(pp, tfname, (size_t)size)) {
208				rcleanup(0);
209				continue;
210			}
211			errmsg = ctl_renametf(pp->printer, tfname);
212			tfname[0] = '\0';
213			if (errmsg != NULL) {
214				frecverr("%s: %s", pp->printer, errmsg);
215				/*NOTREACHED*/
216			}
217			cfcnt++;
218			continue;
219
220		case '\3':	/* read df file */
221			*givenid = '\0';
222			*givenhost = '\0';
223			size = 0;
224			while (*cp >= '0' && *cp <= '9')
225				size = size * 10 + (*cp++ - '0');
226			if (*cp++ != ' ')
227				break;
228			if (strchr(cp, '/')) {
229				frecverr("readjob: %s: illegal path name", cp);
230				/*NOTREACHED*/
231			}
232			if (!chksize(size)) {
233				(void) write(STDOUT_FILENO, "\2", (size_t)1);
234				continue;
235			}
236			strlcpy(dfname, cp, sizeof(dfname));
237			dfcnt++;
238			trstat_init(pp, dfname, dfcnt);
239			(void) readfile(pp, dfname, (size_t)size);
240			trstat_write(pp, TR_RECVING, (size_t)size, givenid,
241			    from_host, givenhost);
242			continue;
243		}
244		frecverr("protocol screwup: %s", line);
245		/*NOTREACHED*/
246	}
247}
248
249/*
250 * Read files send by lpd and copy them to the spooling directory.
251 */
252static int
253readfile(struct printer *pp, char *file, size_t size)
254{
255	register char *cp;
256	char buf[BUFSIZ];
257	size_t amt, i;
258	int err, fd, j;
259
260	fd = open(file, O_CREAT|O_EXCL|O_WRONLY, FILMOD);
261	if (fd < 0) {
262		frecverr("%s: readfile: error on open(%s): %s",
263			 pp->printer, file, strerror(errno));
264		/*NOTREACHED*/
265	}
266	ack();
267	err = 0;
268	for (i = 0; i < size; i += BUFSIZ) {
269		amt = BUFSIZ;
270		cp = buf;
271		if (i + amt > size)
272			amt = size - i;
273		do {
274			j = read(STDOUT_FILENO, cp, amt);
275			if (j <= 0) {
276				frecverr("%s: lost connection", pp->printer);
277				/*NOTREACHED*/
278			}
279			amt -= j;
280			cp += j;
281		} while (amt > 0);
282		amt = BUFSIZ;
283		if (i + amt > size)
284			amt = size - i;
285		if (write(fd, buf, amt) != (ssize_t)amt) {
286			err++;
287			break;
288		}
289	}
290	(void) close(fd);
291	if (err) {
292		frecverr("%s: write error on close(%s)", pp->printer, file);
293		/*NOTREACHED*/
294	}
295	if (noresponse()) {		/* file sent had bad data in it */
296		if (strchr(file, '/') == NULL)
297			(void) unlink(file);
298		return (0);
299	}
300	ack();
301	return (1);
302}
303
304static int
305noresponse(void)
306{
307	char resp;
308
309	if (read(STDOUT_FILENO, &resp, (size_t)1) != 1) {
310		frecverr("lost connection in noresponse()");
311		/*NOTREACHED*/
312	}
313	if (resp == '\0')
314		return(0);
315	return(1);
316}
317
318/*
319 * Check to see if there is enough space on the disk for size bytes.
320 * 1 == OK, 0 == Not OK.
321 */
322static int
323chksize(int size)
324{
325	int spacefree;
326	struct statfs sfb;
327
328	if (statfs(".", &sfb) < 0) {
329		syslog(LOG_ERR, "%s: %m", "statfs(\".\")");
330		return (1);
331	}
332	spacefree = sfb.f_bavail * (sfb.f_bsize / 512);
333	size = (size + 511) / 512;
334	if (minfree + size > spacefree)
335		return(0);
336	return(1);
337}
338
339static int
340read_number(const char *fn)
341{
342	char lin[80];
343	register FILE *fp;
344
345	if ((fp = fopen(fn, "r")) == NULL)
346		return (0);
347	if (fgets(lin, 80, fp) == NULL) {
348		fclose(fp);
349		return (0);
350	}
351	fclose(fp);
352	return (atoi(lin));
353}
354
355/*
356 * Remove all the files associated with the current job being transfered.
357 */
358static void
359rcleanup(int signo __unused)
360{
361	if (tfname[0] && strchr(tfname, '/') == NULL)
362		(void) unlink(tfname);
363	if (dfname[0] && strchr(dfname, '/') == NULL) {
364		do {
365			do
366				(void) unlink(dfname);
367			while (dfname[2]-- != 'A');
368			dfname[2] = 'z';
369		} while (dfname[0]-- != 'd');
370	}
371	dfname[0] = '\0';
372}
373
374#include <stdarg.h>
375
376static void
377frecverr(const char *msg, ...)
378{
379	va_list ap;
380	va_start(ap, msg);
381	syslog(LOG_ERR, "Error receiving job from %s:", from_host);
382	vsyslog(LOG_ERR, msg, ap);
383	va_end(ap);
384	/*
385	 * rcleanup is not called until AFTER logging the error message,
386	 * because rcleanup will zap some variables which may have been
387	 * supplied as parameters for that msg...
388	 */
389	rcleanup(0);
390	/*
391	 * Add a minimal delay before returning the final error code to
392	 * the sending host.  This just in case that machine responds
393	 * this error by INSTANTLY retrying (and instantly re-failing...).
394	 * It would be stupid of the sending host to do that, but if there
395	 * was a broken implementation which did it, the result might be
396	 * obscure performance problems and a flood of syslog messages on
397	 * the receiving host.
398	 */
399	sleep(2);		/* a paranoid throttling measure */
400	putchar('\1');		/* return error code */
401	exit(1);
402}
403