xref: /dragonfly/usr.sbin/lpr/lpd/recvjob.c (revision 65cc0652)
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. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * @(#) Copyright (c) 1983, 1993 The Regents of the University of California.  All rights reserved.
31  * @(#)recvjob.c	8.2 (Berkeley) 4/27/95
32  * $FreeBSD: src/usr.sbin/lpr/lpd/recvjob.c,v 1.14.2.13 2002/06/19 01:46:48 gad Exp $
33  * $DragonFly: src/usr.sbin/lpr/lpd/recvjob.c,v 1.4 2004/12/18 22:48:03 swildner Exp $
34  */
35 
36 /*
37  * Receive printer jobs from the network, queue them and
38  * start the printer daemon.
39  */
40 #include <sys/param.h>
41 #include <sys/mount.h>
42 #include <sys/stat.h>
43 
44 #include <unistd.h>
45 #include <signal.h>
46 #include <fcntl.h>
47 #include <dirent.h>
48 #include <errno.h>
49 #include <syslog.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include "lp.h"
54 #include "lp.local.h"
55 #include "ctlinfo.h"
56 #include "extern.h"
57 #include "pathnames.h"
58 
59 #define ack()	write(STDOUT_FILENO, sp, (size_t)1);
60 
61 static char	 dfname[NAME_MAX];	/* data files */
62 static int	 minfree;       /* keep at least minfree blocks available */
63 static const char	*sp = "";
64 static char	 tfname[NAME_MAX];	/* tmp copy of cf before linking */
65 
66 static int	 chksize(int _size);
67 static void	 frecverr(const char *_msg, ...) __printf0like(1, 2);
68 static int	 noresponse(void);
69 static void	 rcleanup(int _signo);
70 static int	 read_number(const char *_fn);
71 static int	 readfile(struct printer *_pp, char *_file, size_t _size);
72 static int	 readjob(struct printer *_pp);
73 
74 
75 void
76 recvjob(const char *printer)
77 {
78 	struct stat stb;
79 	int status;
80 	struct printer myprinter, *pp = &myprinter;
81 
82 	/*
83 	 * Perform lookup for printer name or abbreviation
84 	 */
85 	init_printer(pp);
86 	status = getprintcap(printer, pp);
87 	switch (status) {
88 	case PCAPERR_OSERR:
89 		frecverr("cannot open printer description file");
90 		break;
91 	case PCAPERR_NOTFOUND:
92 		frecverr("unknown printer %s", printer);
93 		break;
94 	case PCAPERR_TCLOOP:
95 		fatal(pp, "potential reference loop detected in printcap file");
96 	default:
97 		break;
98 	}
99 
100 	close(2);			/* set up log file */
101 	if (open(pp->log_file, O_WRONLY|O_APPEND, 0664) < 0) {
102 		syslog(LOG_ERR, "%s: %m", pp->log_file);
103 		open(_PATH_DEVNULL, O_WRONLY);
104 	}
105 
106 	if (chdir(pp->spool_dir) < 0)
107 		frecverr("%s: chdir(%s): %s", pp->printer, pp->spool_dir,
108 		    strerror(errno));
109 	if (stat(pp->lock_file, &stb) == 0) {
110 		if (stb.st_mode & 010) {
111 			/* queue is disabled */
112 			putchar('\1');		/* return error code */
113 			exit(1);
114 		}
115 	} else if (stat(pp->spool_dir, &stb) < 0)
116 		frecverr("%s: stat(%s): %s", pp->printer, pp->spool_dir,
117 		    strerror(errno));
118 	minfree = 2 * read_number("minfree");	/* scale KB to 512 blocks */
119 	signal(SIGTERM, rcleanup);
120 	signal(SIGPIPE, rcleanup);
121 
122 	if (readjob(pp))
123 		printjob(pp);
124 }
125 
126 /*
127  * Read printer jobs sent by lpd and copy them to the spooling directory.
128  * Return the number of jobs successfully transfered.
129  */
130 static int
131 readjob(struct printer *pp)
132 {
133 	int size;
134 	int cfcnt, dfcnt;
135 	char *cp, *clastp, *errmsg;
136 	char givenid[32], givenhost[MAXHOSTNAMELEN];
137 
138 	ack();
139 	cfcnt = 0;
140 	dfcnt = 0;
141 	for (;;) {
142 		/*
143 		 * Read a command to tell us what to do
144 		 */
145 		cp = line;
146 		clastp = line + sizeof(line) - 1;
147 		do {
148 			size = read(STDOUT_FILENO, cp, (size_t)1);
149 			if (size != (ssize_t)1) {
150 				if (size < (ssize_t)0) {
151 					frecverr("%s: lost connection",
152 					    pp->printer);
153 					/*NOTREACHED*/
154 				}
155 				return (cfcnt);
156 			}
157 		} while ((*cp++ != '\n') && (cp <= clastp));
158 		if (cp > clastp) {
159 			frecverr("%s: readjob overflow", pp->printer);
160 			/*NOTREACHED*/
161 		}
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 			dfcnt = 0;
172 			while (*cp >= '0' && *cp <= '9')
173 				size = size * 10 + (*cp++ - '0');
174 			if (*cp++ != ' ')
175 				break;
176 			/*
177 			 * host name has been authenticated, we use our
178 			 * view of the host name since we may be passed
179 			 * something different than what gethostbyaddr()
180 			 * returns
181 			 */
182 			strlcpy(cp + 6, from_host, sizeof(line)
183 			    + (size_t)(line - cp - 6));
184 			if (strchr(cp, '/')) {
185 				frecverr("readjob: %s: illegal path name", cp);
186 				/*NOTREACHED*/
187 			}
188 			strlcpy(tfname, cp, sizeof(tfname));
189 			tfname[sizeof (tfname) - 1] = '\0';
190 			tfname[0] = 't';
191 			if (!chksize(size)) {
192 				write(STDOUT_FILENO, "\2", (size_t)1);
193 				continue;
194 			}
195 			if (!readfile(pp, tfname, (size_t)size)) {
196 				rcleanup(0);
197 				continue;
198 			}
199 			errmsg = ctl_renametf(pp->printer, tfname);
200 			tfname[0] = '\0';
201 			if (errmsg != NULL) {
202 				frecverr("%s: %s", pp->printer, errmsg);
203 				/*NOTREACHED*/
204 			}
205 			cfcnt++;
206 			continue;
207 
208 		case '\3':	/* read df file */
209 			*givenid = '\0';
210 			*givenhost = '\0';
211 			size = 0;
212 			while (*cp >= '0' && *cp <= '9')
213 				size = size * 10 + (*cp++ - '0');
214 			if (*cp++ != ' ')
215 				break;
216 			if (strchr(cp, '/')) {
217 				frecverr("readjob: %s: illegal path name", cp);
218 				/*NOTREACHED*/
219 			}
220 			if (!chksize(size)) {
221 				write(STDOUT_FILENO, "\2", (size_t)1);
222 				continue;
223 			}
224 			strlcpy(dfname, cp, sizeof(dfname));
225 			dfcnt++;
226 			trstat_init(pp, dfname, dfcnt);
227 			readfile(pp, dfname, (size_t)size);
228 			trstat_write(pp, TR_RECVING, (size_t)size, givenid,
229 			    from_host, givenhost);
230 			continue;
231 		}
232 		frecverr("protocol screwup: %s", line);
233 		/*NOTREACHED*/
234 	}
235 }
236 
237 /*
238  * Read files send by lpd and copy them to the spooling directory.
239  */
240 static int
241 readfile(struct printer *pp, char *file, size_t size)
242 {
243 	char *cp;
244 	char buf[BUFSIZ];
245 	size_t amt, i;
246 	int err, fd, j;
247 
248 	fd = open(file, O_CREAT|O_EXCL|O_WRONLY, FILMOD);
249 	if (fd < 0) {
250 		frecverr("%s: readfile: error on open(%s): %s",
251 			 pp->printer, file, strerror(errno));
252 		/*NOTREACHED*/
253 	}
254 	ack();
255 	err = 0;
256 	for (i = 0; i < size; i += BUFSIZ) {
257 		amt = BUFSIZ;
258 		cp = buf;
259 		if (i + amt > size)
260 			amt = size - i;
261 		do {
262 			j = read(STDOUT_FILENO, cp, amt);
263 			if (j <= 0) {
264 				frecverr("%s: lost connection", pp->printer);
265 				/*NOTREACHED*/
266 			}
267 			amt -= j;
268 			cp += j;
269 		} while (amt > 0);
270 		amt = BUFSIZ;
271 		if (i + amt > size)
272 			amt = size - i;
273 		if (write(fd, buf, amt) != (ssize_t)amt) {
274 			err++;
275 			break;
276 		}
277 	}
278 	close(fd);
279 	if (err) {
280 		frecverr("%s: write error on close(%s)", pp->printer, file);
281 		/*NOTREACHED*/
282 	}
283 	if (noresponse()) {		/* file sent had bad data in it */
284 		if (strchr(file, '/') == NULL)
285 			unlink(file);
286 		return (0);
287 	}
288 	ack();
289 	return (1);
290 }
291 
292 static int
293 noresponse(void)
294 {
295 	char resp;
296 
297 	if (read(STDOUT_FILENO, &resp, (size_t)1) != 1) {
298 		frecverr("lost connection in noresponse()");
299 		/*NOTREACHED*/
300 	}
301 	if (resp == '\0')
302 		return(0);
303 	return(1);
304 }
305 
306 /*
307  * Check to see if there is enough space on the disk for size bytes.
308  * 1 == OK, 0 == Not OK.
309  */
310 static int
311 chksize(int size)
312 {
313 	int spacefree;
314 	struct statfs sfb;
315 
316 	if (statfs(".", &sfb) < 0) {
317 		syslog(LOG_ERR, "%s: %m", "statfs(\".\")");
318 		return (1);
319 	}
320 	spacefree = sfb.f_bavail * (sfb.f_bsize / 512);
321 	size = (size + 511) / 512;
322 	if (minfree + size > spacefree)
323 		return(0);
324 	return(1);
325 }
326 
327 static int
328 read_number(const char *fn)
329 {
330 	char lin[80];
331 	FILE *fp;
332 
333 	if ((fp = fopen(fn, "r")) == NULL)
334 		return (0);
335 	if (fgets(lin, 80, fp) == NULL) {
336 		fclose(fp);
337 		return (0);
338 	}
339 	fclose(fp);
340 	return (atoi(lin));
341 }
342 
343 /*
344  * Remove all the files associated with the current job being transfered.
345  */
346 static void
347 rcleanup(int signo __unused)
348 {
349 	if (tfname[0] && strchr(tfname, '/') == NULL)
350 		unlink(tfname);
351 	if (dfname[0] && strchr(dfname, '/') == NULL) {
352 		do {
353 			do
354 				unlink(dfname);
355 			while (dfname[2]-- != 'A');
356 			dfname[2] = 'z';
357 		} while (dfname[0]-- != 'd');
358 	}
359 	dfname[0] = '\0';
360 }
361 
362 #include <stdarg.h>
363 
364 static void
365 frecverr(const char *msg, ...)
366 {
367 	va_list ap;
368 	va_start(ap, msg);
369 	syslog(LOG_ERR, "Error receiving job from %s:", from_host);
370 	vsyslog(LOG_ERR, msg, ap);
371 	va_end(ap);
372 	/*
373 	 * rcleanup is not called until AFTER logging the error message,
374 	 * because rcleanup will zap some variables which may have been
375 	 * supplied as parameters for that msg...
376 	 */
377 	rcleanup(0);
378 	/*
379 	 * Add a minimal delay before returning the final error code to
380 	 * the sending host.  This just in case that machine responds
381 	 * this error by INSTANTLY retrying (and instantly re-failing...).
382 	 * It would be stupid of the sending host to do that, but if there
383 	 * was a broken implementation which did it, the result might be
384 	 * obscure performance problems and a flood of syslog messages on
385 	 * the receiving host.
386 	 */
387 	sleep(2);		/* a paranoid throttling measure */
388 	putchar('\1');		/* return error code */
389 	exit(1);
390 }
391