xref: /freebsd/usr.sbin/lpr/lpc/lpc.c (revision 7750ad47a9a7dbc83f87158464170c8640723293)
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  * 4. 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 
31 #ifndef lint
32 static const char copyright[] =
33 "@(#) Copyright (c) 1983, 1993\n\
34 	The Regents of the University of California.  All rights reserved.\n";
35 #endif /* not lint */
36 
37 #if 0
38 #ifndef lint
39 static char sccsid[] = "@(#)lpc.c	8.3 (Berkeley) 4/28/95";
40 #endif /* not lint */
41 #endif
42 
43 #include "lp.cdefs.h"		/* A cross-platform version of <sys/cdefs.h> */
44 __FBSDID("$FreeBSD$");
45 
46 #include <sys/param.h>
47 
48 #include <ctype.h>
49 #include <dirent.h>
50 #include <err.h>
51 #include <grp.h>
52 #include <setjmp.h>
53 #include <signal.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <syslog.h>
57 #include <string.h>
58 #include <unistd.h>
59 #include <histedit.h>
60 
61 #include "lp.h"
62 #include "lpc.h"
63 #include "extern.h"
64 
65 #ifndef LPR_OPER
66 #define LPR_OPER	"operator"	/* group name of lpr operators */
67 #endif
68 
69 /*
70  * lpc -- line printer control program
71  */
72 
73 #define MAX_CMDLINE	200
74 #define MAX_MARGV	20
75 static int	fromatty;
76 
77 static char	cmdline[MAX_CMDLINE];
78 static int	margc;
79 static char	*margv[MAX_MARGV];
80 uid_t		uid, euid;
81 
82 int			 main(int _argc, char *_argv[]);
83 static void		 cmdscanner(void);
84 static struct cmd	*getcmd(const char *_name);
85 static void		 intr(int _signo);
86 static void		 makeargv(void);
87 static int		 ingroup(const char *_grname);
88 
89 int
90 main(int argc, char *argv[])
91 {
92 	register struct cmd *c;
93 
94 	euid = geteuid();
95 	uid = getuid();
96 	seteuid(uid);
97 	progname = argv[0];
98 	openlog("lpd", 0, LOG_LPR);
99 
100 	if (--argc > 0) {
101 		c = getcmd(*++argv);
102 		if (c == (struct cmd *)-1) {
103 			printf("?Ambiguous command\n");
104 			exit(1);
105 		}
106 		if (c == 0) {
107 			printf("?Invalid command\n");
108 			exit(1);
109 		}
110 		if ((c->c_opts & LPC_PRIVCMD) && getuid() &&
111 		    ingroup(LPR_OPER) == 0) {
112 			printf("?Privileged command\n");
113 			exit(1);
114 		}
115 		if (c->c_generic != 0)
116 			generic(c->c_generic, c->c_opts, c->c_handler,
117 			    argc, argv);
118 		else
119 			(*c->c_handler)(argc, argv);
120 		exit(0);
121 	}
122 	fromatty = isatty(fileno(stdin));
123 	if (!fromatty)
124 		signal(SIGINT, intr);
125 	for (;;) {
126 		cmdscanner();
127 	}
128 }
129 
130 static void
131 intr(int signo __unused)
132 {
133 	/* (the '__unused' is just to avoid a compile-time warning) */
134 	exit(0);
135 }
136 
137 static const char *
138 lpc_prompt(void)
139 {
140 	return ("lpc> ");
141 }
142 
143 /*
144  * Command parser.
145  */
146 static void
147 cmdscanner(void)
148 {
149 	register struct cmd *c;
150 	static EditLine *el;
151 	static History *hist;
152 	HistEvent he;
153 	size_t len;
154 	int num;
155 	const char *bp;
156 
157 	num = 0;
158 	bp = NULL;
159 	el = NULL;
160 	hist = NULL;
161 	for (;;) {
162 		if (fromatty) {
163 			if (!el) {
164 				el = el_init("lpc", stdin, stdout, stderr);
165 				hist = history_init();
166 				history(hist, &he, H_SETSIZE, 100);
167 				el_set(el, EL_HIST, history, hist);
168 				el_set(el, EL_EDITOR, "emacs");
169 				el_set(el, EL_PROMPT, lpc_prompt);
170 				el_set(el, EL_SIGNAL, 1);
171 				el_source(el, NULL);
172 				/*
173 				 * EditLine init may call 'cgetset()' to set a
174 				 * capability-db meant for termcap (eg: to set
175 				 * terminal type 'xterm').  Reset that now, or
176 				 * that same db-information will be used for
177 				 * printcap (giving us an "xterm" printer, with
178 				 * all kinds of invalid capabilities...).
179 				 */
180 				cgetset(NULL);
181 			}
182 			if ((bp = el_gets(el, &num)) == NULL || num == 0)
183 				quit(0, NULL);
184 
185 			len = (num > MAX_CMDLINE - 1) ? MAX_CMDLINE - 1 : num;
186 			memcpy(cmdline, bp, len);
187 			cmdline[len] = 0;
188 			history(hist, &he, H_ENTER, bp);
189 
190 		} else {
191 			if (fgets(cmdline, MAX_CMDLINE, stdin) == NULL)
192 				quit(0, NULL);
193 			if (cmdline[0] == 0 || cmdline[0] == '\n')
194 				break;
195 		}
196 
197 		makeargv();
198 		if (margc == 0)
199 			continue;
200 		if (el != NULL && el_parse(el, margc, margv) != -1)
201 			continue;
202 
203 		c = getcmd(margv[0]);
204 		if (c == (struct cmd *)-1) {
205 			printf("?Ambiguous command\n");
206 			continue;
207 		}
208 		if (c == 0) {
209 			printf("?Invalid command\n");
210 			continue;
211 		}
212 		if ((c->c_opts & LPC_PRIVCMD) && getuid() &&
213 		    ingroup(LPR_OPER) == 0) {
214 			printf("?Privileged command\n");
215 			continue;
216 		}
217 
218 		/*
219 		 * Two different commands might have the same generic rtn
220 		 * (eg: "clean" and "tclean"), and just use different
221 		 * handler routines for distinct command-setup.  The handler
222 		 * routine might also be set on a generic routine for
223 		 * initial parameter processing.
224 		 */
225 		if (c->c_generic != 0)
226 			generic(c->c_generic, c->c_opts, c->c_handler,
227 			    margc, margv);
228 		else
229 			(*c->c_handler)(margc, margv);
230 	}
231 }
232 
233 static struct cmd *
234 getcmd(const char *name)
235 {
236 	register const char *p, *q;
237 	register struct cmd *c, *found;
238 	register int nmatches, longest;
239 
240 	longest = 0;
241 	nmatches = 0;
242 	found = 0;
243 	for (c = cmdtab; (p = c->c_name); c++) {
244 		for (q = name; *q == *p++; q++)
245 			if (*q == 0)		/* exact match? */
246 				return(c);
247 		if (!*q) {			/* the name was a prefix */
248 			if (q - name > longest) {
249 				longest = q - name;
250 				nmatches = 1;
251 				found = c;
252 			} else if (q - name == longest)
253 				nmatches++;
254 		}
255 	}
256 	if (nmatches > 1)
257 		return((struct cmd *)-1);
258 	return(found);
259 }
260 
261 /*
262  * Slice a string up into argc/argv.
263  */
264 static void
265 makeargv(void)
266 {
267 	register char *cp;
268 	register char **argp = margv;
269 	register int n = 0;
270 
271 	margc = 0;
272 	for (cp = cmdline; *cp && (size_t)(cp - cmdline) < sizeof(cmdline) &&
273 	    n < MAX_MARGV - 1; n++) {
274 		while (isspace(*cp))
275 			cp++;
276 		if (*cp == '\0')
277 			break;
278 		*argp++ = cp;
279 		margc += 1;
280 		while (*cp != '\0' && !isspace(*cp))
281 			cp++;
282 		if (*cp == '\0')
283 			break;
284 		*cp++ = '\0';
285 	}
286 	*argp++ = 0;
287 }
288 
289 #define HELPINDENT (sizeof ("directory"))
290 
291 /*
292  * Help command.
293  */
294 void
295 help(int argc, char *argv[])
296 {
297 	register struct cmd *c;
298 
299 	if (argc == 1) {
300 		register int i, j, w;
301 		int columns, width = 0, lines;
302 
303 		printf("Commands may be abbreviated.  Commands are:\n\n");
304 		for (c = cmdtab; c->c_name; c++) {
305 			int len = strlen(c->c_name);
306 
307 			if (len > width)
308 				width = len;
309 		}
310 		width = (width + 8) &~ 7;
311 		columns = 80 / width;
312 		if (columns == 0)
313 			columns = 1;
314 		lines = (NCMDS + columns - 1) / columns;
315 		for (i = 0; i < lines; i++) {
316 			for (j = 0; j < columns; j++) {
317 				c = cmdtab + j * lines + i;
318 				if (c->c_name)
319 					printf("%s", c->c_name);
320 				if (c + lines >= &cmdtab[NCMDS]) {
321 					printf("\n");
322 					break;
323 				}
324 				w = strlen(c->c_name);
325 				while (w < width) {
326 					w = (w + 8) &~ 7;
327 					putchar('\t');
328 				}
329 			}
330 		}
331 		return;
332 	}
333 	while (--argc > 0) {
334 		register char *arg;
335 		arg = *++argv;
336 		c = getcmd(arg);
337 		if (c == (struct cmd *)-1)
338 			printf("?Ambiguous help command %s\n", arg);
339 		else if (c == (struct cmd *)0)
340 			printf("?Invalid help command %s\n", arg);
341 		else
342 			printf("%-*s\t%s\n", (int) HELPINDENT,
343 				c->c_name, c->c_help);
344 	}
345 }
346 
347 /*
348  * return non-zero if the user is a member of the given group
349  */
350 static int
351 ingroup(const char *grname)
352 {
353 	static struct group *gptr=NULL;
354 	static int ngroups = 0;
355 	static long ngroups_max;
356 	static gid_t *groups;
357 	register gid_t gid;
358 	register int i;
359 
360 	if (gptr == NULL) {
361 		if ((gptr = getgrnam(grname)) == NULL) {
362 			warnx("warning: unknown group '%s'", grname);
363 			return(0);
364 		}
365 		ngroups_max = sysconf(_SC_NGROUPS_MAX);
366 		if ((groups = malloc(sizeof(gid_t) * ngroups_max)) == NULL)
367 			err(1, "malloc");
368 		ngroups = getgroups(ngroups_max, groups);
369 		if (ngroups < 0)
370 			err(1, "getgroups");
371 	}
372 	gid = gptr->gr_gid;
373 	for (i = 0; i < ngroups; i++)
374 		if (gid == groups[i])
375 			return(1);
376 	return(0);
377 }
378 
379 /*
380  * Routine to get the information for a single printer (which will be
381  * called by the routines which implement individual commands).
382  * Note: This is for commands operating on a *single* printer.
383  */
384 struct printer *
385 setup_myprinter(char *pwanted, struct printer *pp, int sump_opts)
386 {
387 	int cdres, cmdstatus;
388 
389 	init_printer(pp);
390 	cmdstatus = getprintcap(pwanted, pp);
391 	switch (cmdstatus) {
392 	default:
393 		fatal(pp, "%s", pcaperr(cmdstatus));
394 		/* NOTREACHED */
395 	case PCAPERR_NOTFOUND:
396 		printf("unknown printer %s\n", pwanted);
397 		return (NULL);
398 	case PCAPERR_TCOPEN:
399 		printf("warning: %s: unresolved tc= reference(s)", pwanted);
400 		break;
401 	case PCAPERR_SUCCESS:
402 		break;
403 	}
404 	if ((sump_opts & SUMP_NOHEADER) == 0)
405 		printf("%s:\n", pp->printer);
406 
407 	if (sump_opts & SUMP_CHDIR_SD) {
408 		seteuid(euid);
409 		cdres = chdir(pp->spool_dir);
410 		seteuid(uid);
411 		if (cdres < 0) {
412 			printf("\tcannot chdir to %s\n", pp->spool_dir);
413 			free_printer(pp);
414 			return (NULL);
415 		}
416 	}
417 
418 	return (pp);
419 }
420