xref: /netbsd/usr.sbin/lpr/common_source/common.c (revision 076d8406)
1 /*	$NetBSD: common.c,v 1.44 2023/05/13 11:48:19 andvar Exp $	*/
2 
3 /*
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <sys/cdefs.h>
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)common.c	8.5 (Berkeley) 4/28/95";
41 #else
42 __RCSID("$NetBSD: common.c,v 1.44 2023/05/13 11:48:19 andvar Exp $");
43 #endif
44 #endif /* not lint */
45 
46 #include <sys/param.h>
47 #include <sys/stat.h>
48 #include <sys/time.h>
49 
50 #include <sys/socket.h>
51 #include <netinet/in.h>
52 #include <arpa/inet.h>
53 #include <netdb.h>
54 
55 #include <dirent.h>
56 #include <errno.h>
57 #include <unistd.h>
58 #include <stdlib.h>
59 #include <stdio.h>
60 #include <string.h>
61 #include <ifaddrs.h>
62 #include "lp.h"
63 #include "lp.local.h"
64 #include "pathnames.h"
65 
66 /*
67  * Routines and data common to all the line printer functions.
68  */
69 
70 const char	*AF;		/* accounting file */
71 long		 BR;		/* baud rate if lp is a tty */
72 const char	*CF;		/* name of cifplot filter (per job) */
73 const char	*DF;		/* name of tex filter (per job) */
74 long		 DU;		/* daeomon user-id */
75 long		 FC;		/* flags to clear if lp is a tty */
76 const char	*FF;		/* form feed string */
77 long		 FS;		/* flags to set if lp is a tty */
78 const char	*GF;		/* name of graph(1G) filter (per job) */
79 long		 HL;		/* print header last */
80 const char	*IF;		/* name of input filter (created per job) */
81 const char	*LF;		/* log file for error messages */
82 const char	*LO;		/* lock file name */
83 const char	*LP;		/* line printer device name */
84 long		 MC;		/* maximum number of copies allowed */
85 const char	*MS;		/* stty flags to set if lp is a tty */
86 long		 MX;		/* maximum number of blocks to copy */
87 const char	*NF;		/* name of ditroff filter (per job) */
88 const char	*OF;		/* name of output filter (created once) */
89 const char	*PF;		/* name of postscript filter (per job) */
90 long		 PL;		/* page length */
91 long		 PW;		/* page width */
92 long		 PX;		/* page width in pixels */
93 long		 PY;		/* page length in pixels */
94 const char	*RF;		/* name of fortran text filter (per job) */
95 const char	*RG;		/* resricted group */
96 const char	*RM;		/* remote machine name */
97 const char	*RP;		/* remote printer name */
98 long		 RS;		/* restricted to those with local accounts */
99 long		 RW;		/* open LP for reading and writing */
100 long		 SB;		/* short banner instead of normal header */
101 long		 SC;		/* suppress multiple copies */
102 const char	*SD;		/* spool directory */
103 long		 SF;		/* suppress FF on each print job */
104 long		 SH;		/* suppress header page */
105 const char	*ST;		/* status file name */
106 const char	*TF;		/* name of troff filter (per job) */
107 const char	*TR;		/* trailer string to be output when Q empties */
108 const char	*VF;		/* name of vplot/vrast filter (per job) */
109 long		 XC;		/* flags to clear for local mode */
110 long		 XS;		/* flags to set for local mode */
111 
112 char	line[BUFSIZ];
113 int	remote;		/* true if sending files to a remote host */
114 
115 extern uid_t	uid, euid;
116 
117 static int compar(const void *, const void *);
118 
119 const char *
gethost(const char * hname)120 gethost(const char *hname)
121 {
122 	const char *p = strchr(hname, '@');
123 	return p ? ++p : hname;
124 }
125 
126 /*
127  * Create a TCP connection to host "rhost". If "rhost" is of the
128  * form port@host, use the specified port. Otherwise use the
129  * default printer port. Most of this code comes from rcmd.c.
130  */
131 int
getport(const char * rhost)132 getport(const char *rhost)
133 {
134 	struct addrinfo hints, *res, *r;
135 	u_int timo = 1;
136 	int s, lport = IPPORT_RESERVED - 1;
137 	int error;
138 	int refuse, trial;
139 	char hbuf[NI_MAXSERV], *ptr;
140 	const char *port = "printer";
141 	const char *hostname = rhost;
142 
143 	/*
144 	 * Get the host address and port number to connect to.
145 	 */
146 	if (rhost == NULL)
147 		fatal("no remote host to connect to");
148 	(void)strlcpy(hbuf, rhost, sizeof(hbuf));
149 	for (ptr = hbuf; *ptr; ptr++)
150 		if (*ptr == '@') {
151 			*ptr++ = '\0';
152 			port = hbuf;
153 			hostname = ptr;
154 			break;
155 		}
156 	(void)memset(&hints, 0, sizeof(hints));
157 	hints.ai_family = PF_UNSPEC;
158 	hints.ai_socktype = SOCK_STREAM;
159 	error = getaddrinfo(hostname, port, &hints, &res);
160 	if (error)
161 		fatal("printer/tcp: %s", gai_strerror(error));
162 
163 	/*
164 	 * Try connecting to the server.
165 	 */
166 retry:
167 	s = -1;
168 	refuse = trial = 0;
169 	for (r = res; r; r = r->ai_next) {
170 		trial++;
171 retryport:
172 		seteuid(euid);
173 		s = rresvport_af(&lport, r->ai_family);
174 		seteuid(uid);
175 		if (s < 0)
176 			return(-1);
177 		if (connect(s, r->ai_addr, r->ai_addrlen) < 0) {
178 			error = errno;
179 			(void)close(s);
180 			s = -1;
181 			errno = error;
182 			if (errno == EADDRINUSE) {
183 				lport--;
184 				goto retryport;
185 			} else if (errno == ECONNREFUSED)
186 				refuse++;
187 			continue;
188 		} else
189 			break;
190 	}
191 	if (s < 0 && trial == refuse && timo <= 16) {
192 		sleep(timo);
193 		timo *= 2;
194 		goto retry;
195 	}
196 	if (res)
197 		freeaddrinfo(res);
198 	return(s);
199 }
200 
201 /*
202  * Getline reads a line from the control file cfp, removes tabs, converts
203  *  new-line to null and leaves it in line.
204  * Returns 0 at EOF or the number of characters read.
205  */
206 size_t
get_line(FILE * cfp)207 get_line(FILE *cfp)
208 {
209 	size_t linel = 0;
210 	int c;
211 	char *lp = line;
212 
213 	while ((c = getc(cfp)) != '\n' && linel+1<sizeof(line)) {
214 		if (c == EOF)
215 			return(0);
216 		if (c == '\t') {
217 			do {
218 				*lp++ = ' ';
219 				linel++;
220 			} while ((linel & 07) != 0 && linel+1 < sizeof(line));
221 			continue;
222 		}
223 		*lp++ = c;
224 		linel++;
225 	}
226 	*lp++ = '\0';
227 	return(linel);
228 }
229 
230 /*
231  * Scan the current directory and make a list of daemon files sorted by
232  * creation time.
233  * Return the number of entries and a pointer to the list.
234  */
235 int
getq(struct queue ** namelist[])236 getq(struct queue **namelist[])
237 {
238 	struct dirent *d;
239 	struct queue *q, **queue = NULL, **nqueue;
240 	struct stat stbuf;
241 	DIR *dirp;
242 	u_int nitems = 0, arraysz;
243 
244 	seteuid(euid);
245 	dirp = opendir(SD);
246 	seteuid(uid);
247 	if (dirp == NULL)
248 		return(-1);
249 	if (fstat(dirp->dd_fd, &stbuf) < 0)
250 		goto errdone;
251 
252 	/*
253 	 * Estimate the array size by taking the size of the directory file
254 	 * and dividing it by a multiple of the minimum size entry.
255 	 */
256 	arraysz = (int)(stbuf.st_size / 24);
257 	queue = calloc(arraysz, sizeof(struct queue *));
258 	if (queue == NULL)
259 		goto errdone;
260 
261 	while ((d = readdir(dirp)) != NULL) {
262 		if (d->d_name[0] != 'c' || d->d_name[1] != 'f'
263 		    || d->d_name[2] == '\0')
264 			continue;	/* daemon control files only */
265 		seteuid(euid);
266 		if (stat(d->d_name, &stbuf) < 0) {
267 			seteuid(uid);
268 			continue;	/* Doesn't exist */
269 		}
270 		seteuid(uid);
271 		q = (struct queue *)malloc(sizeof(time_t)+strlen(d->d_name)+1);
272 		if (q == NULL)
273 			goto errdone;
274 		q->q_time = stbuf.st_mtime;
275 		strcpy(q->q_name, d->d_name);	/* XXX: strcpy is safe */
276 		/*
277 		 * Check to make sure the array has space left and
278 		 * realloc the maximum size.
279 		 */
280 		if (++nitems > arraysz) {
281 			nqueue = (struct queue **)realloc(queue,
282 				arraysz * 2 * sizeof(struct queue *));
283 			if (nqueue == NULL) {
284 				free(q);
285 				goto errdone;
286 			}
287 			(void)memset(&nqueue[arraysz], 0,
288 			    arraysz * sizeof(nqueue[0]));
289 			queue = nqueue;
290 			arraysz *= 2;
291 		}
292 		queue[nitems-1] = q;
293 	}
294 	closedir(dirp);
295 	if (nitems)
296 		qsort(queue, nitems, sizeof(struct queue *), compar);
297 	*namelist = queue;
298 	return(nitems);
299 
300 errdone:
301 	freeq(queue, nitems);
302 	closedir(dirp);
303 	return(-1);
304 }
305 
306 void
freeq(struct queue ** namelist,u_int nitems)307 freeq(struct queue **namelist, u_int nitems)
308 {
309 	u_int i;
310 	if (namelist == NULL)
311 		return;
312 	for (i = 0; i < nitems; i++)
313 		if (namelist[i])
314 			free(namelist[i]);
315 	free(namelist);
316 }
317 
318 /*
319  * Compare modification times.
320  */
321 static int
compar(const void * p1,const void * p2)322 compar(const void *p1, const void *p2)
323 {
324 	const struct queue *const *q1 = p1;
325 	const struct queue *const *q2 = p2;
326 	int j1, j2;
327 
328 	if ((*q1)->q_time < (*q2)->q_time)
329 		return -1;
330 	if ((*q1)->q_time > (*q2)->q_time)
331 		return 1;
332 
333 	j1 = atoi((*q1)->q_name+3);
334 	j2 = atoi((*q2)->q_name+3);
335 
336         if (j1 == j2)
337                 return 0;
338         if ((j1 < j2 && j2-j1 < 500) || (j1 > j2 && j1-j2 > 500))
339                 return -1;
340         if ((j1 < j2 && j2-j1 > 500) || (j1 > j2 && j1-j2 < 500))
341                 return 1;
342 
343 	return 0;
344 }
345 
346 /*
347  * Figure out whether the local machine is the same
348  * as the remote machine (RM) entry (if it exists).
349  */
350 const char *
checkremote(void)351 checkremote(void)
352 {
353 	struct addrinfo hints, *res0;
354 	static char errbuf[128];
355 	int error;
356 	struct ifaddrs *ifap;
357 #if defined(INET6) && defined(__KAME__)
358 	char lname[NI_MAXHOST], rname[NI_MAXHOST];
359 	struct addrinfo *res;
360 	struct ifaddrs *ifa;
361 	const int niflags = NI_NUMERICHOST;
362 	struct sockaddr_in6 sin6;
363 	struct sockaddr_in6 *sin6p;
364 #endif
365 
366 	remote = 0;	/* assume printer is local on failure */
367 
368 	if (RM == NULL)
369 		return NULL;
370 
371 	/* get the local interface addresses */
372 	if (getifaddrs(&ifap) < 0) {
373 		(void)snprintf(errbuf, sizeof(errbuf),
374 		    "unable to get local interface address: %s",
375 		    strerror(errno));
376 		return errbuf;
377 	}
378 
379 	/* get the remote host addresses (RM) */
380 	memset(&hints, 0, sizeof(hints));
381 	hints.ai_flags = AI_CANONNAME;
382 	hints.ai_family = PF_UNSPEC;
383 	hints.ai_socktype = SOCK_STREAM;
384 	error = getaddrinfo(gethost(RM), NULL, &hints, &res0);
385 	if (error) {
386 		(void)snprintf(errbuf, sizeof(errbuf),
387 		    "unable to resolve remote machine %s: %s",
388 		    RM, gai_strerror(error));
389 		freeifaddrs(ifap);
390 		return errbuf;
391 	}
392 
393 	remote = 1;	/* assume printer is remote */
394 
395 #if defined(INET6) && defined(__KAME__)
396 	for (res = res0; res; res = res->ai_next) {
397 		if (getnameinfo(res->ai_addr, res->ai_addrlen,
398 		    rname, sizeof(rname), NULL, 0, niflags) != 0)
399 			continue;
400 		for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
401 			sin6p = (struct sockaddr_in6 *)ifa->ifa_addr;
402 			if (ifa->ifa_addr->sa_family == AF_INET6 &&
403 			    ifa->ifa_addr->sa_len == sizeof(sin6)) {
404 				inet6_getscopeid(sin6p, 3);
405 				if (getnameinfo((struct sockaddr *)&sin6,
406 				    sin6.sin6_len, lname, sizeof(lname),
407 				    NULL, 0, niflags) != 0)
408 					continue;
409 				if (strcmp(rname, lname) == 0) {
410 					remote = 0;
411 					goto done;
412 				}
413 			}
414 		}
415 	}
416 done:
417 #endif
418 	freeaddrinfo(res0);
419 	freeifaddrs(ifap);
420 	return NULL;
421 }
422 
423 /* sleep n milliseconds */
424 void
delay(int n)425 delay(int n)
426 {
427 	struct timespec tdelay;
428 
429 	if (n <= 0 || n > 10000)
430 		fatal("unreasonable delay period (%d)", n);
431 	tdelay.tv_sec = n / 1000;
432 	tdelay.tv_nsec = (n % 1000) * 1000000;
433 	nanosleep(&tdelay, NULL);
434 }
435 
436 void
getprintcap(const char * pr)437 getprintcap(const char *pr)
438 {
439 	char *cp;
440 	const char *dp;
441 	int i;
442 
443 	if ((i = cgetent(&bp, printcapdb, pr)) == -2)
444 		fatal("can't open printer description file");
445 	else if (i == -1)
446 		fatal("unknown printer: %s", pr);
447 	else if (i == -3)
448 		fatal("potential reference loop detected in printcap file");
449 
450 	LP = cgetstr(bp, DEFLP, &cp) == -1 ? _PATH_DEFDEVLP : cp;
451 	RP = cgetstr(bp, "rp", &cp) == -1 ? DEFLP : cp;
452 	SD = cgetstr(bp, "sd", &cp) == -1 ? _PATH_DEFSPOOL : cp;
453 	LO = cgetstr(bp, "lo", &cp) == -1 ? DEFLOCK : cp;
454 	ST = cgetstr(bp, "st", &cp) == -1 ? DEFSTAT : cp;
455 	RM = cgetstr(bp, "rm", &cp) == -1 ? NULL : cp;
456 	if ((dp = checkremote()) != NULL)
457 		printf("Warning: %s\n", dp);
458 	LF = cgetstr(bp, "lf", &cp) == -1 ? _PATH_CONSOLE : cp;
459 }
460 
461 /*
462  * Make sure there's some work to do before forking off a child
463  */
464 int
ckqueue(char * cap)465 ckqueue(char *cap)
466 {
467 	struct dirent *d;
468 	DIR *dirp;
469 	const char *spooldir;
470 	char *sd = NULL;
471 	int rv = 0;
472 
473 	spooldir = cgetstr(cap, "sd", &sd) == -1 ? _PATH_DEFSPOOL : sd;
474 	if ((dirp = opendir(spooldir)) == NULL) {
475 		rv = -1;
476 		goto out;
477 	}
478 	while ((d = readdir(dirp)) != NULL) {
479 		if (d->d_name[0] != 'c' || d->d_name[1] != 'f')
480 			continue;	/* daemon control files only */
481 		rv = 1;
482 		break;
483 	}
484 out:
485 	if (dirp != NULL)
486 		closedir(dirp);
487 	if (spooldir != sd)
488 		free(sd);
489 	return (rv);
490 }
491