xref: /freebsd/usr.sbin/lpr/lpd/recvjob.c (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
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
36 static 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
43 static 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("$FreeBSD$");
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 
80 static char	 dfname[NAME_MAX];	/* data files */
81 static int	 minfree;       /* keep at least minfree blocks available */
82 static const char	*sp = "";
83 static char	 tfname[NAME_MAX];	/* tmp copy of cf before linking */
84 
85 static int	 chksize(int _size);
86 static void	 frecverr(const char *_msg, ...) __printf0like(1, 2);
87 static int	 noresponse(void);
88 static void	 rcleanup(int _signo);
89 static int	 read_number(const char *_fn);
90 static int	 readfile(struct printer *_pp, char *_file, size_t _size);
91 static int	 readjob(struct printer *_pp);
92 
93 
94 void
95 recvjob(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  */
149 static int
150 readjob(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  */
259 static int
260 readfile(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 
311 static int
312 noresponse(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  */
329 static int
330 chksize(int size)
331 {
332 	int 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 
346 static int
347 read_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  */
365 static void
366 rcleanup(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 
383 static void
384 frecverr(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