lpc.c revision 330897 
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 * 4. 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#ifndef lint
34static const char copyright[] =
35"@(#) Copyright (c) 1983, 1993\n\
36	The Regents of the University of California.  All rights reserved.\n";
37#endif /* not lint */
38
39#if 0
40#ifndef lint
41static char sccsid[] = "@(#)lpc.c	8.3 (Berkeley) 4/28/95";
42#endif /* not lint */
43#endif
44
45#include "lp.cdefs.h"		/* A cross-platform version of <sys/cdefs.h> */
46__FBSDID("$FreeBSD: stable/11/usr.sbin/lpr/lpc/lpc.c 330897 2018-03-14 03:19:51Z eadler $");
47
48#include <sys/param.h>
49
50#include <ctype.h>
51#include <dirent.h>
52#include <err.h>
53#include <grp.h>
54#include <setjmp.h>
55#include <signal.h>
56#include <stdio.h>
57#include <stdlib.h>
58#include <syslog.h>
59#include <string.h>
60#include <unistd.h>
61#include <histedit.h>
62
63#include "lp.h"
64#include "lpc.h"
65#include "extern.h"
66
67#ifndef LPR_OPER
68#define LPR_OPER	"operator"	/* group name of lpr operators */
69#endif
70
71/*
72 * lpc -- line printer control program
73 */
74
75#define MAX_CMDLINE	200
76#define MAX_MARGV	20
77static int	fromatty;
78
79static char	cmdline[MAX_CMDLINE];
80static int	margc;
81static char	*margv[MAX_MARGV];
82uid_t		uid, euid;
83
84int			 main(int _argc, char *_argv[]);
85static void		 cmdscanner(void);
86static struct cmd	*getcmd(const char *_name);
87static void		 intr(int _signo);
88static void		 makeargv(void);
89static int		 ingroup(const char *_grname);
90
91int
92main(int argc, char *argv[])
93{
94	register struct cmd *c;
95
96	euid = geteuid();
97	uid = getuid();
98	PRIV_END
99	progname = argv[0];
100	openlog("lpd", 0, LOG_LPR);
101
102	if (--argc > 0) {
103		c = getcmd(*++argv);
104		if (c == (struct cmd *)-1) {
105			printf("?Ambiguous command\n");
106			exit(1);
107		}
108		if (c == NULL) {
109			printf("?Invalid command\n");
110			exit(1);
111		}
112		if ((c->c_opts & LPC_PRIVCMD) && getuid() &&
113		    ingroup(LPR_OPER) == 0) {
114			printf("?Privileged command\n");
115			exit(1);
116		}
117		if (c->c_generic != NULL)
118			generic(c->c_generic, c->c_opts, c->c_handler,
119			    argc, argv);
120		else
121			(*c->c_handler)(argc, argv);
122		exit(0);
123	}
124	fromatty = isatty(fileno(stdin));
125	if (!fromatty)
126		signal(SIGINT, intr);
127	for (;;) {
128		cmdscanner();
129	}
130}
131
132static void
133intr(int signo __unused)
134{
135	/* (the '__unused' is just to avoid a compile-time warning) */
136	exit(0);
137}
138
139static const char *
140lpc_prompt(void)
141{
142	return ("lpc> ");
143}
144
145/*
146 * Command parser.
147 */
148static void
149cmdscanner(void)
150{
151	register struct cmd *c;
152	static EditLine *el;
153	static History *hist;
154	HistEvent he;
155	size_t len;
156	int num;
157	const char *bp;
158
159	num = 0;
160	bp = NULL;
161	el = NULL;
162	hist = NULL;
163	for (;;) {
164		if (fromatty) {
165			if (!el) {
166				el = el_init("lpc", stdin, stdout, stderr);
167				hist = history_init();
168				history(hist, &he, H_SETSIZE, 100);
169				el_set(el, EL_HIST, history, hist);
170				el_set(el, EL_EDITOR, "emacs");
171				el_set(el, EL_PROMPT, lpc_prompt);
172				el_set(el, EL_SIGNAL, 1);
173				el_source(el, NULL);
174				/*
175				 * EditLine init may call 'cgetset()' to set a
176				 * capability-db meant for termcap (eg: to set
177				 * terminal type 'xterm').  Reset that now, or
178				 * that same db-information will be used for
179				 * printcap (giving us an "xterm" printer, with
180				 * all kinds of invalid capabilities...).
181				 */
182				cgetset(NULL);
183			}
184			if ((bp = el_gets(el, &num)) == NULL || num == 0)
185				quit(0, NULL);
186
187			len = MIN(MAX_CMDLINE - 1, num);
188			memcpy(cmdline, bp, len);
189			cmdline[len] = 0;
190			history(hist, &he, H_ENTER, bp);
191
192		} else {
193			if (fgets(cmdline, MAX_CMDLINE, stdin) == NULL)
194				quit(0, NULL);
195			if (cmdline[0] == 0 || cmdline[0] == '\n')
196				break;
197		}
198
199		makeargv();
200		if (margc == 0)
201			continue;
202		if (el != NULL && el_parse(el, margc, margv) != -1)
203			continue;
204
205		c = getcmd(margv[0]);
206		if (c == (struct cmd *)-1) {
207			printf("?Ambiguous command\n");
208			continue;
209		}
210		if (c == NULL) {
211			printf("?Invalid command\n");
212			continue;
213		}
214		if ((c->c_opts & LPC_PRIVCMD) && getuid() &&
215		    ingroup(LPR_OPER) == 0) {
216			printf("?Privileged command\n");
217			continue;
218		}
219
220		/*
221		 * Two different commands might have the same generic rtn
222		 * (eg: "clean" and "tclean"), and just use different
223		 * handler routines for distinct command-setup.  The handler
224		 * routine might also be set on a generic routine for
225		 * initial parameter processing.
226		 */
227		if (c->c_generic != NULL)
228			generic(c->c_generic, c->c_opts, c->c_handler,
229			    margc, margv);
230		else
231			(*c->c_handler)(margc, margv);
232	}
233}
234
235static struct cmd *
236getcmd(const char *name)
237{
238	register const char *p, *q;
239	register struct cmd *c, *found;
240	register int nmatches, longest;
241
242	longest = 0;
243	nmatches = 0;
244	found = NULL;
245	for (c = cmdtab; (p = c->c_name); c++) {
246		for (q = name; *q == *p++; q++)
247			if (*q == 0)		/* exact match? */
248				return(c);
249		if (!*q) {			/* the name was a prefix */
250			if (q - name > longest) {
251				longest = q - name;
252				nmatches = 1;
253				found = c;
254			} else if (q - name == longest)
255				nmatches++;
256		}
257	}
258	if (nmatches > 1)
259		return((struct cmd *)-1);
260	return(found);
261}
262
263/*
264 * Slice a string up into argc/argv.
265 */
266static void
267makeargv(void)
268{
269	register char *cp;
270	register char **argp = margv;
271	register int n = 0;
272
273	margc = 0;
274	for (cp = cmdline; *cp && (size_t)(cp - cmdline) < sizeof(cmdline) &&
275	    n < MAX_MARGV - 1; n++) {
276		while (isspace(*cp))
277			cp++;
278		if (*cp == '\0')
279			break;
280		*argp++ = cp;
281		margc += 1;
282		while (*cp != '\0' && !isspace(*cp))
283			cp++;
284		if (*cp == '\0')
285			break;
286		*cp++ = '\0';
287	}
288	*argp++ = NULL;
289}
290
291#define HELPINDENT (sizeof ("directory"))
292
293/*
294 * Help command.
295 */
296void
297help(int argc, char *argv[])
298{
299	register struct cmd *c;
300
301	if (argc == 1) {
302		register int i, j, w;
303		int columns, width = 0, lines;
304
305		printf("Commands may be abbreviated.  Commands are:\n\n");
306		for (c = cmdtab; c->c_name; c++) {
307			int len = strlen(c->c_name);
308
309			if (len > width)
310				width = len;
311		}
312		width = (width + 8) &~ 7;
313		columns = 80 / width;
314		if (columns == 0)
315			columns = 1;
316		lines = (NCMDS + columns - 1) / columns;
317		for (i = 0; i < lines; i++) {
318			for (j = 0; j < columns; j++) {
319				c = cmdtab + j * lines + i;
320				if (c->c_name)
321					printf("%s", c->c_name);
322				if (c + lines >= &cmdtab[NCMDS]) {
323					printf("\n");
324					break;
325				}
326				w = strlen(c->c_name);
327				while (w < width) {
328					w = (w + 8) &~ 7;
329					putchar('\t');
330				}
331			}
332		}
333		return;
334	}
335	while (--argc > 0) {
336		register char *arg;
337		arg = *++argv;
338		c = getcmd(arg);
339		if (c == (struct cmd *)-1)
340			printf("?Ambiguous help command %s\n", arg);
341		else if (c == (struct cmd *)0)
342			printf("?Invalid help command %s\n", arg);
343		else
344			printf("%-*s\t%s\n", (int) HELPINDENT,
345				c->c_name, c->c_help);
346	}
347}
348
349/*
350 * return non-zero if the user is a member of the given group
351 */
352static int
353ingroup(const char *grname)
354{
355	static struct group *gptr=NULL;
356	static int ngroups = 0;
357	static long ngroups_max;
358	static gid_t *groups;
359	register gid_t gid;
360	register int i;
361
362	if (gptr == NULL) {
363		if ((gptr = getgrnam(grname)) == NULL) {
364			warnx("warning: unknown group '%s'", grname);
365			return(0);
366		}
367		ngroups_max = sysconf(_SC_NGROUPS_MAX);
368		if ((groups = malloc(sizeof(gid_t) * ngroups_max)) == NULL)
369			err(1, "malloc");
370		ngroups = getgroups(ngroups_max, groups);
371		if (ngroups < 0)
372			err(1, "getgroups");
373	}
374	gid = gptr->gr_gid;
375	for (i = 0; i < ngroups; i++)
376		if (gid == groups[i])
377			return(1);
378	return(0);
379}
380
381/*
382 * Routine to get the information for a single printer (which will be
383 * called by the routines which implement individual commands).
384 * Note: This is for commands operating on a *single* printer.
385 */
386struct printer *
387setup_myprinter(char *pwanted, struct printer *pp, int sump_opts)
388{
389	int cdres, cmdstatus;
390
391	init_printer(pp);
392	cmdstatus = getprintcap(pwanted, pp);
393	switch (cmdstatus) {
394	default:
395		fatal(pp, "%s", pcaperr(cmdstatus));
396		/* NOTREACHED */
397	case PCAPERR_NOTFOUND:
398		printf("unknown printer %s\n", pwanted);
399		return (NULL);
400	case PCAPERR_TCOPEN:
401		printf("warning: %s: unresolved tc= reference(s)", pwanted);
402		break;
403	case PCAPERR_SUCCESS:
404		break;
405	}
406	if ((sump_opts & SUMP_NOHEADER) == 0)
407		printf("%s:\n", pp->printer);
408
409	if (sump_opts & SUMP_CHDIR_SD) {
410		PRIV_START
411		cdres = chdir(pp->spool_dir);
412		PRIV_END
413		if (cdres < 0) {
414			printf("\tcannot chdir to %s\n", pp->spool_dir);
415			free_printer(pp);
416			return (NULL);
417		}
418	}
419
420	return (pp);
421}
422