recvjob.c revision 118881 
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 118881 2003-08-13 20:31:33Z gad $");
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
75static char	 dfname[NAME_MAX];	/* data files */
76static int	 minfree;       /* keep at least minfree blocks available */
77static const char	*sp = "";
78static char	 tfname[NAME_MAX];	/* tmp copy of cf before linking */
79
80static int	 chksize(int _size);
81static void	 frecverr(const char *_msg, ...) __printf0like(1, 2);
82static int	 noresponse(void);
83static void	 rcleanup(int _signo);
84static int	 read_number(const char *_fn);
85static int	 readfile(struct printer *_pp, char *_file, size_t _size);
86static int	 readjob(struct printer *_pp);
87
88
89void
90recvjob(const char *printer)
91{
92	struct stat stb;
93	int status;
94	struct printer myprinter, *pp = &myprinter;
95
96	/*
97	 * Perform lookup for printer name or abbreviation
98	 */
99	init_printer(pp);
100	status = getprintcap(printer, pp);
101	switch (status) {
102	case PCAPERR_OSERR:
103		frecverr("cannot open printer description file");
104		break;
105	case PCAPERR_NOTFOUND:
106		frecverr("unknown printer %s", printer);
107		break;
108	case PCAPERR_TCLOOP:
109		fatal(pp, "potential reference loop detected in printcap file");
110	default:
111		break;
112	}
113
114	(void) close(STDERR_FILENO);			/* set up log file */
115	if (open(pp->log_file, O_WRONLY|O_APPEND, 0664) < 0) {
116		syslog(LOG_ERR, "%s: %m", pp->log_file);
117		(void) open(_PATH_DEVNULL, O_WRONLY);
118	}
119
120	if (chdir(pp->spool_dir) < 0)
121		frecverr("%s: chdir(%s): %s", pp->printer, pp->spool_dir,
122		    strerror(errno));
123	if (stat(pp->lock_file, &stb) == 0) {
124		if (stb.st_mode & 010) {
125			/* queue is disabled */
126			putchar('\1');		/* return error code */
127			exit(1);
128		}
129	} else if (stat(pp->spool_dir, &stb) < 0)
130		frecverr("%s: stat(%s): %s", pp->printer, pp->spool_dir,
131		    strerror(errno));
132	minfree = 2 * read_number("minfree");	/* scale KB to 512 blocks */
133	signal(SIGTERM, rcleanup);
134	signal(SIGPIPE, rcleanup);
135
136	if (readjob(pp))
137		printjob(pp);
138}
139
140/*
141 * Read printer jobs sent by lpd and copy them to the spooling directory.
142 * Return the number of jobs successfully transfered.
143 */
144static int
145readjob(struct printer *pp)
146{
147	register int size;
148	int cfcnt, dfcnt;
149	char *cp, *clastp, *errmsg;
150	char givenid[32], givenhost[MAXHOSTNAMELEN];
151
152	ack();
153	cfcnt = 0;
154	dfcnt = 0;
155	for (;;) {
156		/*
157		 * Read a command to tell us what to do
158		 */
159		cp = line;
160		clastp = line + sizeof(line) - 1;
161		do {
162			size = read(STDOUT_FILENO, cp, (size_t)1);
163			if (size != (ssize_t)1) {
164				if (size < (ssize_t)0) {
165					frecverr("%s: lost connection",
166					    pp->printer);
167					/*NOTREACHED*/
168				}
169				return (cfcnt);
170			}
171		} while ((*cp++ != '\n') && (cp <= clastp));
172		if (cp > clastp) {
173			frecverr("%s: readjob overflow", pp->printer);
174			/*NOTREACHED*/
175		}
176		*--cp = '\0';
177		cp = line;
178		switch (*cp++) {
179		case '\1':	/* cleanup because data sent was bad */
180			rcleanup(0);
181			continue;
182
183		case '\2':	/* read cf file */
184			size = 0;
185			dfcnt = 0;
186			while (*cp >= '0' && *cp <= '9')
187				size = size * 10 + (*cp++ - '0');
188			if (*cp++ != ' ')
189				break;
190			/*
191			 * host name has been authenticated, we use our
192			 * view of the host name since we may be passed
193			 * something different than what gethostbyaddr()
194			 * returns
195			 */
196			strlcpy(cp + 6, from_host, sizeof(line)
197			    + (size_t)(line - cp - 6));
198			if (strchr(cp, '/')) {
199				frecverr("readjob: %s: illegal path name", cp);
200				/*NOTREACHED*/
201			}
202			strlcpy(tfname, cp, sizeof(tfname));
203			tfname[sizeof (tfname) - 1] = '\0';
204			tfname[0] = 't';
205			if (!chksize(size)) {
206				(void) write(STDOUT_FILENO, "\2", (size_t)1);
207				continue;
208			}
209			if (!readfile(pp, tfname, (size_t)size)) {
210				rcleanup(0);
211				continue;
212			}
213			errmsg = ctl_renametf(pp->printer, tfname);
214			tfname[0] = '\0';
215			if (errmsg != NULL) {
216				frecverr("%s: %s", pp->printer, errmsg);
217				/*NOTREACHED*/
218			}
219			cfcnt++;
220			continue;
221
222		case '\3':	/* read df file */
223			*givenid = '\0';
224			*givenhost = '\0';
225			size = 0;
226			while (*cp >= '0' && *cp <= '9')
227				size = size * 10 + (*cp++ - '0');
228			if (*cp++ != ' ')
229				break;
230			if (strchr(cp, '/')) {
231				frecverr("readjob: %s: illegal path name", cp);
232				/*NOTREACHED*/
233			}
234			if (!chksize(size)) {
235				(void) write(STDOUT_FILENO, "\2", (size_t)1);
236				continue;
237			}
238			strlcpy(dfname, cp, sizeof(dfname));
239			dfcnt++;
240			trstat_init(pp, dfname, dfcnt);
241			(void) readfile(pp, dfname, (size_t)size);
242			trstat_write(pp, TR_RECVING, (size_t)size, givenid,
243			    from_host, givenhost);
244			continue;
245		}
246		frecverr("protocol screwup: %s", line);
247		/*NOTREACHED*/
248	}
249}
250
251/*
252 * Read files send by lpd and copy them to the spooling directory.
253 */
254static int
255readfile(struct printer *pp, char *file, size_t size)
256{
257	register char *cp;
258	char buf[BUFSIZ];
259	size_t amt, i;
260	int err, fd, j;
261
262	fd = open(file, O_CREAT|O_EXCL|O_WRONLY, FILMOD);
263	if (fd < 0) {
264		frecverr("%s: readfile: error on open(%s): %s",
265			 pp->printer, file, strerror(errno));
266		/*NOTREACHED*/
267	}
268	ack();
269	err = 0;
270	for (i = 0; i < size; i += BUFSIZ) {
271		amt = BUFSIZ;
272		cp = buf;
273		if (i + amt > size)
274			amt = size - i;
275		do {
276			j = read(STDOUT_FILENO, cp, amt);
277			if (j <= 0) {
278				frecverr("%s: lost connection", pp->printer);
279				/*NOTREACHED*/
280			}
281			amt -= j;
282			cp += j;
283		} while (amt > 0);
284		amt = BUFSIZ;
285		if (i + amt > size)
286			amt = size - i;
287		if (write(fd, buf, amt) != (ssize_t)amt) {
288			err++;
289			break;
290		}
291	}
292	(void) close(fd);
293	if (err) {
294		frecverr("%s: write error on close(%s)", pp->printer, file);
295		/*NOTREACHED*/
296	}
297	if (noresponse()) {		/* file sent had bad data in it */
298		if (strchr(file, '/') == NULL)
299			(void) unlink(file);
300		return (0);
301	}
302	ack();
303	return (1);
304}
305
306static int
307noresponse(void)
308{
309	char resp;
310
311	if (read(STDOUT_FILENO, &resp, (size_t)1) != 1) {
312		frecverr("lost connection in noresponse()");
313		/*NOTREACHED*/
314	}
315	if (resp == '\0')
316		return(0);
317	return(1);
318}
319
320/*
321 * Check to see if there is enough space on the disk for size bytes.
322 * 1 == OK, 0 == Not OK.
323 */
324static int
325chksize(int size)
326{
327	int spacefree;
328	struct statfs sfb;
329
330	if (statfs(".", &sfb) < 0) {
331		syslog(LOG_ERR, "%s: %m", "statfs(\".\")");
332		return (1);
333	}
334	spacefree = sfb.f_bavail * (sfb.f_bsize / 512);
335	size = (size + 511) / 512;
336	if (minfree + size > spacefree)
337		return(0);
338	return(1);
339}
340
341static int
342read_number(const char *fn)
343{
344	char lin[80];
345	register FILE *fp;
346
347	if ((fp = fopen(fn, "r")) == NULL)
348		return (0);
349	if (fgets(lin, 80, fp) == NULL) {
350		fclose(fp);
351		return (0);
352	}
353	fclose(fp);
354	return (atoi(lin));
355}
356
357/*
358 * Remove all the files associated with the current job being transfered.
359 */
360static void
361rcleanup(int signo __unused)
362{
363	if (tfname[0] && strchr(tfname, '/') == NULL)
364		(void) unlink(tfname);
365	if (dfname[0] && strchr(dfname, '/') == NULL) {
366		do {
367			do
368				(void) unlink(dfname);
369			while (dfname[2]-- != 'A');
370			dfname[2] = 'z';
371		} while (dfname[0]-- != 'd');
372	}
373	dfname[0] = '\0';
374}
375
376#include <stdarg.h>
377
378static void
379frecverr(const char *msg, ...)
380{
381	va_list ap;
382	va_start(ap, msg);
383	syslog(LOG_ERR, "Error receiving job from %s:", from_host);
384	vsyslog(LOG_ERR, msg, ap);
385	va_end(ap);
386	/*
387	 * rcleanup is not called until AFTER logging the error message,
388	 * because rcleanup will zap some variables which may have been
389	 * supplied as parameters for that msg...
390	 */
391	rcleanup(0);
392	/*
393	 * Add a minimal delay before returning the final error code to
394	 * the sending host.  This just in case that machine responds
395	 * this error by INSTANTLY retrying (and instantly re-failing...).
396	 * It would be stupid of the sending host to do that, but if there
397	 * was a broken implementation which did it, the result might be
398	 * obscure performance problems and a flood of syslog messages on
399	 * the receiving host.
400	 */
401	sleep(2);		/* a paranoid throttling measure */
402	putchar('\1');		/* return error code */
403	exit(1);
404}
405