Home | History | Annotate | Line # | Download | only in lpd
recvjob.c revision 1.19 
      1 /*	$NetBSD: recvjob.c,v 1.19 2004/04/21 01:05:48 christos Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1983, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  * 1. Redistributions of source code must retain the above copyright
     12  *    notice, this list of conditions and the following disclaimer.
     13  * 2. Redistributions in binary form must reproduce the above copyright
     14  *    notice, this list of conditions and the following disclaimer in the
     15  *    documentation and/or other materials provided with the distribution.
     16  * 3. Neither the name of the University nor the names of its contributors
     17  *    may be used to endorse or promote products derived from this software
     18  *    without specific prior written permission.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     30  * SUCH DAMAGE.
     31  */
     32 
     33 #include <sys/cdefs.h>
     34 
     35 #ifndef lint
     36 __COPYRIGHT("@(#) Copyright (c) 1983, 1993\n\
     37 	The Regents of the University of California.  All rights reserved.\n");
     38 #endif /* not lint */
     39 
     40 #ifndef lint
     41 #if 0
     42 static char sccsid[] = "@(#)recvjob.c	8.2 (Berkeley) 4/27/95";
     43 #else
     44 __RCSID("$NetBSD: recvjob.c,v 1.19 2004/04/21 01:05:48 christos Exp $");
     45 #endif
     46 #endif /* not lint */
     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 <syslog.h>
     61 #include <stdio.h>
     62 #include <stdlib.h>
     63 #include <string.h>
     64 #include "lp.h"
     65 #include "lp.local.h"
     66 #include "extern.h"
     67 #include "pathnames.h"
     68 
     69 #define ack()	(void)write(STDOUT_FILENO, sp, 1);
     70 
     71 static char	 dfname[NAME_MAX];	/* data files */
     72 static int	 minfree;       /* keep at least minfree blocks available */
     73 static char	*sp = "";
     74 static char	 tfname[NAME_MAX];	/* tmp copy of cf before linking */
     75 
     76 static int        chksize(int);
     77 static void       frecverr(const char *, ...)
     78 	__attribute__((__format__(__printf__, 1, 2)));
     79 static int        noresponse(void);
     80 static void       rcleanup(int);
     81 static int        read_number(char *);
     82 static int        readfile(char *, int);
     83 static int        readjob(void);
     84 
     85 
     86 void
     87 recvjob(void)
     88 {
     89 	struct stat stb;
     90 	int status, fd;
     91 
     92 	/*
     93 	 * Perform lookup for printer name or abbreviation
     94 	 */
     95 	if ((status = cgetent(&bp, printcapdb, printer)) == -2)
     96 		frecverr("cannot open printer description file");
     97 	else if (status == -1)
     98 		frecverr("unknown printer %s", printer);
     99 	else if (status == -3)
    100 		fatal("potential reference loop detected in printcap file");
    101 
    102 	if (cgetstr(bp, "lf", &LF) == -1)
    103 		LF = _PATH_CONSOLE;
    104 	if (cgetstr(bp, "sd", &SD) == -1)
    105 		SD = _PATH_DEFSPOOL;
    106 	if (cgetstr(bp, "lo", &LO) == -1)
    107 		LO = DEFLOCK;
    108 
    109 	/* Set up the log file. */
    110 	if ((fd = open(LF, O_WRONLY|O_APPEND, 0664)) < 0) {
    111 		syslog(LOG_ERR, "%s: %m", LF);
    112 		fd = open(_PATH_DEVNULL, O_WRONLY);
    113 	}
    114 	if (fd > 0) {
    115 		(void) dup2(fd, STDERR_FILENO);
    116 		(void) close(fd);
    117 	} else
    118 		(void) close(STDERR_FILENO);
    119 
    120 	if (chdir(SD) < 0)
    121 		frecverr("%s: %s: %m", printer, SD);
    122 	if (stat(LO, &stb) == 0) {
    123 		if (stb.st_mode & 010) {
    124 			/* queue is disabled */
    125 			putchar('\1');		/* return error code */
    126 			exit(1);
    127 		}
    128 	} else if (stat(SD, &stb) < 0)
    129 		frecverr("%s: %s: %m", printer, SD);
    130 	minfree = 2 * read_number("minfree");	/* scale KB to 512 blocks */
    131 	signal(SIGTERM, rcleanup);
    132 	signal(SIGPIPE, rcleanup);
    133 
    134 	if (readjob())
    135 		printjob();
    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  */
    142 static int
    143 readjob(void)
    144 {
    145 	int size, nfiles;
    146 	char *cp;
    147 
    148 	ack();
    149 	nfiles = 0;
    150 	for (;;) {
    151 		/*
    152 		 * Read a command to tell us what to do
    153 		 */
    154 		cp = line;
    155 		do {
    156 			if ((size = read(STDOUT_FILENO, cp, 1)) != 1) {
    157 				if (size < 0)
    158 					frecverr("%s: Lost connection",
    159 					    printer);
    160 				return(nfiles);
    161 			}
    162 		} while (*cp++ != '\n' && (cp - line + 1) < sizeof(line));
    163 		if (cp - line + 1 >= sizeof(line))
    164 			frecverr("readjob overflow");
    165 		*--cp = '\0';
    166 		cp = line;
    167 		switch (*cp++) {
    168 		case '\1':	/* cleanup because data sent was bad */
    169 			rcleanup(0);
    170 			continue;
    171 
    172 		case '\2':	/* read cf file */
    173 			size = 0;
    174 			while (*cp >= '0' && *cp <= '9')
    175 				size = size * 10 + (*cp++ - '0');
    176 			if (*cp++ != ' ')
    177 				break;
    178 			/*
    179 			 * host name has been authenticated, we use our
    180 			 * view of the host name since we may be passed
    181 			 * something different than what gethostbyaddr()
    182 			 * returns
    183 			 */
    184  			(void)strlcpy(cp + 6, from,
    185 			    sizeof(line) + line - cp - 6);
    186 			if (strchr(cp, '/'))
    187 				frecverr("readjob: %s: illegal path name", cp);
    188 			(void)strlcpy(tfname, cp, sizeof(tfname));
    189 			tfname[0] = 't';
    190 			if (!chksize(size)) {
    191 				(void)write(STDOUT_FILENO, "\2", 1);
    192 				continue;
    193 			}
    194 			if (!readfile(tfname, size)) {
    195 				rcleanup(0);
    196 				continue;
    197 			}
    198 			if (link(tfname, cp) < 0)
    199 				frecverr("%s: %m", tfname);
    200 			(void)unlink(tfname);
    201 			tfname[0] = '\0';
    202 			nfiles++;
    203 			continue;
    204 
    205 		case '\3':	/* read df file */
    206 			size = 0;
    207 			while (*cp >= '0' && *cp <= '9')
    208 				size = size * 10 + (*cp++ - '0');
    209 			if (*cp++ != ' ')
    210 				break;
    211 			if (!chksize(size)) {
    212 				(void)write(STDOUT_FILENO, "\2", 1);
    213 				continue;
    214 			}
    215 			if (strchr(cp, '/'))
    216 				frecverr("readjob: %s: illegal path name", cp);
    217 			(void)strlcpy(dfname, cp, sizeof(dfname));
    218 			(void)readfile(dfname, size);
    219 			continue;
    220 		}
    221 		frecverr("protocol screwup: %s", line);
    222 	}
    223 }
    224 
    225 /*
    226  * Read files send by lpd and copy them to the spooling directory.
    227  */
    228 static int
    229 readfile(char *file, int size)
    230 {
    231 	char *cp;
    232 	char buf[BUFSIZ];
    233 	int i, j, amt;
    234 	int fd, err;
    235 
    236 	fd = open(file, O_CREAT|O_EXCL|O_WRONLY, FILMOD);
    237 	if (fd < 0)
    238 		frecverr("readfile: %s: illegal path name: %m", file);
    239 	ack();
    240 	err = 0;
    241 	for (i = 0; i < size; i += BUFSIZ) {
    242 		amt = BUFSIZ;
    243 		cp = buf;
    244 		if (i + amt > size)
    245 			amt = size - i;
    246 		do {
    247 			j = read(STDOUT_FILENO, cp, amt);
    248 			if (j <= 0)
    249 				frecverr("Lost connection");
    250 			amt -= j;
    251 			cp += j;
    252 		} while (amt > 0);
    253 		amt = BUFSIZ;
    254 		if (i + amt > size)
    255 			amt = size - i;
    256 		if (write(fd, buf, amt) != amt) {
    257 			err++;
    258 			break;
    259 		}
    260 	}
    261 	(void)close(fd);
    262 	if (err)
    263 		frecverr("%s: write error", file);
    264 	if (noresponse()) {		/* file sent had bad data in it */
    265 		(void)unlink(file);
    266 		return(0);
    267 	}
    268 	ack();
    269 	return(1);
    270 }
    271 
    272 static int
    273 noresponse(void)
    274 {
    275 	char resp;
    276 
    277 	if (read(STDOUT_FILENO, &resp, 1) != 1)
    278 		frecverr("Lost connection");
    279 	if (resp == '\0')
    280 		return(0);
    281 	return(1);
    282 }
    283 
    284 /*
    285  * Check to see if there is enough space on the disk for size bytes.
    286  * 1 == OK, 0 == Not OK.
    287  */
    288 static int
    289 chksize(int size)
    290 {
    291 	int spacefree;
    292 	struct statvfs sfb;
    293 
    294 	if (statvfs(".", &sfb) < 0) {
    295 		syslog(LOG_ERR, "%s: %m", "statfs(\".\")");
    296 		return (1);
    297 	}
    298 	spacefree = sfb.f_bavail * (sfb.f_frsize / 512);
    299 	size = (size + 511) / 512;
    300 	if (minfree + size > spacefree)
    301 		return(0);
    302 	return(1);
    303 }
    304 
    305 static int
    306 read_number(char *fn)
    307 {
    308 	char lin[80];
    309 	FILE *fp;
    310 
    311 	if ((fp = fopen(fn, "r")) == NULL)
    312 		return (0);
    313 	if (fgets(lin, 80, fp) == NULL) {
    314 		fclose(fp);
    315 		return (0);
    316 	}
    317 	fclose(fp);
    318 	return (atoi(lin));
    319 }
    320 
    321 /*
    322  * Remove all the files associated with the current job being transfered.
    323  */
    324 static void
    325 rcleanup(int signo)
    326 {
    327 	if (tfname[0])
    328 		(void)unlink(tfname);
    329 	if (dfname[0])
    330 		do {
    331 			do {
    332 				if (strchr(dfname, '/') == 0)
    333 					(void)unlink(dfname);
    334 			} while (dfname[2]-- != 'A');
    335 			dfname[2] = 'z';
    336 		} while (dfname[0]-- != 'd');
    337 	dfname[0] = '\0';
    338 }
    339 
    340 #include <stdarg.h>
    341 
    342 static void
    343 frecverr(const char *msg, ...)
    344 {
    345 	extern char fromb[];
    346 	va_list ap;
    347 
    348 	va_start(ap, msg);
    349 	rcleanup(0);
    350 	syslog(LOG_ERR, "%s", fromb);
    351 	vsyslog(LOG_ERR, msg, ap);
    352 	va_end(ap);
    353 	putchar('\1');		/* return error code */
    354 	exit(1);
    355 }
    356