xref: /freebsd/usr.sbin/lpr/lpc/lpc.c (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
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 "lp.cdefs.h"		/* A cross-platform version of <sys/cdefs.h> */
34 #include <sys/param.h>
35 
36 #include <ctype.h>
37 #include <dirent.h>
38 #include <err.h>
39 #include <grp.h>
40 #include <setjmp.h>
41 #include <signal.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <syslog.h>
45 #include <string.h>
46 #include <unistd.h>
47 #include <histedit.h>
48 
49 #include "lp.h"
50 #include "lpc.h"
51 #include "extern.h"
52 
53 #ifndef LPR_OPER
54 #define LPR_OPER	"operator"	/* group name of lpr operators */
55 #endif
56 
57 /*
58  * lpc -- line printer control program
59  */
60 
61 #define MAX_CMDLINE	200
62 #define MAX_MARGV	20
63 static int	fromatty;
64 
65 static char	cmdline[MAX_CMDLINE];
66 static int	margc;
67 static char	*margv[MAX_MARGV];
68 uid_t		uid, euid;
69 
70 int			 main(int _argc, char *_argv[]);
71 static void		 cmdscanner(void);
72 static struct cmd	*getcmd(const char *_name);
73 static void		 intr(int _signo);
74 static void		 makeargv(void);
75 static int		 ingroup(const char *_grname);
76 
77 int
78 main(int argc, char *argv[])
79 {
80 	register struct cmd *c;
81 
82 	euid = geteuid();
83 	uid = getuid();
84 	PRIV_END
85 	progname = argv[0];
86 	openlog("lpd", 0, LOG_LPR);
87 
88 	if (--argc > 0) {
89 		c = getcmd(*++argv);
90 		if (c == (struct cmd *)-1) {
91 			printf("?Ambiguous command\n");
92 			exit(1);
93 		}
94 		if (c == NULL) {
95 			printf("?Invalid command\n");
96 			exit(1);
97 		}
98 		if ((c->c_opts & LPC_PRIVCMD) && getuid() &&
99 		    ingroup(LPR_OPER) == 0) {
100 			printf("?Privileged command\n");
101 			exit(1);
102 		}
103 		if (c->c_generic != NULL)
104 			generic(c->c_generic, c->c_opts, c->c_handler,
105 			    argc, argv);
106 		else
107 			(*c->c_handler)(argc, argv);
108 		exit(0);
109 	}
110 	fromatty = isatty(fileno(stdin));
111 	if (!fromatty)
112 		signal(SIGINT, intr);
113 	for (;;) {
114 		cmdscanner();
115 	}
116 }
117 
118 static void
119 intr(int signo __unused)
120 {
121 	/* (the '__unused' is just to avoid a compile-time warning) */
122 	exit(0);
123 }
124 
125 static const char *
126 lpc_prompt(void)
127 {
128 	return ("lpc> ");
129 }
130 
131 /*
132  * Command parser.
133  */
134 static void
135 cmdscanner(void)
136 {
137 	register struct cmd *c;
138 	static EditLine *el;
139 	static History *hist;
140 	HistEvent he;
141 	size_t len;
142 	int num;
143 	const char *bp;
144 
145 	num = 0;
146 	bp = NULL;
147 	el = NULL;
148 	hist = NULL;
149 	for (;;) {
150 		if (fromatty) {
151 			if (!el) {
152 				el = el_init("lpc", stdin, stdout, stderr);
153 				hist = history_init();
154 				history(hist, &he, H_SETSIZE, 100);
155 				el_set(el, EL_HIST, history, hist);
156 				el_set(el, EL_EDITOR, "emacs");
157 				el_set(el, EL_PROMPT, lpc_prompt);
158 				el_set(el, EL_SIGNAL, 1);
159 				el_source(el, NULL);
160 				/*
161 				 * EditLine init may call 'cgetset()' to set a
162 				 * capability-db meant for termcap (eg: to set
163 				 * terminal type 'xterm').  Reset that now, or
164 				 * that same db-information will be used for
165 				 * printcap (giving us an "xterm" printer, with
166 				 * all kinds of invalid capabilities...).
167 				 */
168 				cgetset(NULL);
169 			}
170 			if ((bp = el_gets(el, &num)) == NULL || num == 0)
171 				quit(0, NULL);
172 
173 			len = MIN(MAX_CMDLINE - 1, num);
174 			memcpy(cmdline, bp, len);
175 			cmdline[len] = 0;
176 			history(hist, &he, H_ENTER, bp);
177 
178 		} else {
179 			if (fgets(cmdline, MAX_CMDLINE, stdin) == NULL)
180 				quit(0, NULL);
181 			if (cmdline[0] == 0 || cmdline[0] == '\n')
182 				break;
183 		}
184 
185 		makeargv();
186 		if (margc == 0)
187 			continue;
188 		if (el != NULL && el_parse(el, margc, (const char **)margv) != -1)
189 			continue;
190 
191 		c = getcmd(margv[0]);
192 		if (c == (struct cmd *)-1) {
193 			printf("?Ambiguous command\n");
194 			continue;
195 		}
196 		if (c == NULL) {
197 			printf("?Invalid command\n");
198 			continue;
199 		}
200 		if ((c->c_opts & LPC_PRIVCMD) && getuid() &&
201 		    ingroup(LPR_OPER) == 0) {
202 			printf("?Privileged command\n");
203 			continue;
204 		}
205 
206 		/*
207 		 * Two different commands might have the same generic rtn
208 		 * (eg: "clean" and "tclean"), and just use different
209 		 * handler routines for distinct command-setup.  The handler
210 		 * routine might also be set on a generic routine for
211 		 * initial parameter processing.
212 		 */
213 		if (c->c_generic != NULL)
214 			generic(c->c_generic, c->c_opts, c->c_handler,
215 			    margc, margv);
216 		else
217 			(*c->c_handler)(margc, margv);
218 	}
219 }
220 
221 static struct cmd *
222 getcmd(const char *name)
223 {
224 	register const char *p, *q;
225 	register struct cmd *c, *found;
226 	register int nmatches, longest;
227 
228 	longest = 0;
229 	nmatches = 0;
230 	found = NULL;
231 	for (c = cmdtab; (p = c->c_name); c++) {
232 		for (q = name; *q == *p++; q++)
233 			if (*q == 0)		/* exact match? */
234 				return(c);
235 		if (!*q) {			/* the name was a prefix */
236 			if (q - name > longest) {
237 				longest = q - name;
238 				nmatches = 1;
239 				found = c;
240 			} else if (q - name == longest)
241 				nmatches++;
242 		}
243 	}
244 	if (nmatches > 1)
245 		return((struct cmd *)-1);
246 	return(found);
247 }
248 
249 /*
250  * Slice a string up into argc/argv.
251  */
252 static void
253 makeargv(void)
254 {
255 	register char *cp;
256 	register char **argp = margv;
257 	register int n = 0;
258 
259 	margc = 0;
260 	for (cp = cmdline; *cp && (size_t)(cp - cmdline) < sizeof(cmdline) &&
261 	    n < MAX_MARGV - 1; n++) {
262 		while (isspace(*cp))
263 			cp++;
264 		if (*cp == '\0')
265 			break;
266 		*argp++ = cp;
267 		margc += 1;
268 		while (*cp != '\0' && !isspace(*cp))
269 			cp++;
270 		if (*cp == '\0')
271 			break;
272 		*cp++ = '\0';
273 	}
274 	*argp++ = NULL;
275 }
276 
277 #define HELPINDENT (sizeof ("directory"))
278 
279 /*
280  * Help command.
281  */
282 void
283 help(int argc, char *argv[])
284 {
285 	register struct cmd *c;
286 
287 	if (argc == 1) {
288 		register int i, j, w;
289 		int columns, width = 0, lines;
290 
291 		printf("Commands may be abbreviated.  Commands are:\n\n");
292 		for (c = cmdtab; c->c_name; c++) {
293 			int len = strlen(c->c_name);
294 
295 			if (len > width)
296 				width = len;
297 		}
298 		width = (width + 8) &~ 7;
299 		columns = 80 / width;
300 		if (columns == 0)
301 			columns = 1;
302 		lines = (NCMDS + columns - 1) / columns;
303 		for (i = 0; i < lines; i++) {
304 			for (j = 0; j < columns; j++) {
305 				c = cmdtab + j * lines + i;
306 				if (c->c_name)
307 					printf("%s", c->c_name);
308 				if (c + lines >= &cmdtab[NCMDS]) {
309 					printf("\n");
310 					break;
311 				}
312 				w = strlen(c->c_name);
313 				while (w < width) {
314 					w = (w + 8) &~ 7;
315 					putchar('\t');
316 				}
317 			}
318 		}
319 		return;
320 	}
321 	while (--argc > 0) {
322 		register char *arg;
323 		arg = *++argv;
324 		c = getcmd(arg);
325 		if (c == (struct cmd *)-1)
326 			printf("?Ambiguous help command %s\n", arg);
327 		else if (c == (struct cmd *)0)
328 			printf("?Invalid help command %s\n", arg);
329 		else
330 			printf("%-*s\t%s\n", (int) HELPINDENT,
331 				c->c_name, c->c_help);
332 	}
333 }
334 
335 /*
336  * return non-zero if the user is a member of the given group
337  */
338 static int
339 ingroup(const char *grname)
340 {
341 	static struct group *gptr=NULL;
342 	static int ngroups = 0;
343 	static long ngroups_max;
344 	static gid_t *groups;
345 	register gid_t gid;
346 	register int i;
347 
348 	if (gptr == NULL) {
349 		if ((gptr = getgrnam(grname)) == NULL) {
350 			warnx("warning: unknown group '%s'", grname);
351 			return(0);
352 		}
353 		ngroups_max = sysconf(_SC_NGROUPS_MAX);
354 		if ((groups = malloc(sizeof(gid_t) * ngroups_max)) == NULL)
355 			err(1, "malloc");
356 		ngroups = getgroups(ngroups_max, groups);
357 		if (ngroups < 0)
358 			err(1, "getgroups");
359 	}
360 	gid = gptr->gr_gid;
361 	for (i = 0; i < ngroups; i++)
362 		if (gid == groups[i])
363 			return(1);
364 	return(0);
365 }
366 
367 /*
368  * Routine to get the information for a single printer (which will be
369  * called by the routines which implement individual commands).
370  * Note: This is for commands operating on a *single* printer.
371  */
372 struct printer *
373 setup_myprinter(char *pwanted, struct printer *pp, int sump_opts)
374 {
375 	int cdres, cmdstatus;
376 
377 	init_printer(pp);
378 	cmdstatus = getprintcap(pwanted, pp);
379 	switch (cmdstatus) {
380 	default:
381 		fatal(pp, "%s", pcaperr(cmdstatus));
382 		/* NOTREACHED */
383 	case PCAPERR_NOTFOUND:
384 		printf("unknown printer %s\n", pwanted);
385 		return (NULL);
386 	case PCAPERR_TCOPEN:
387 		printf("warning: %s: unresolved tc= reference(s)", pwanted);
388 		break;
389 	case PCAPERR_SUCCESS:
390 		break;
391 	}
392 	if ((sump_opts & SUMP_NOHEADER) == 0)
393 		printf("%s:\n", pp->printer);
394 
395 	if (sump_opts & SUMP_CHDIR_SD) {
396 		PRIV_START
397 		cdres = chdir(pp->spool_dir);
398 		PRIV_END
399 		if (cdres < 0) {
400 			printf("\tcannot chdir to %s\n", pp->spool_dir);
401 			free_printer(pp);
402 			return (NULL);
403 		}
404 	}
405 
406 	return (pp);
407 }
408