1/*-
2 * Copyright (c) 2003-2007 Tim Kientzle
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer
10 *    in this position and unchanged.
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 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27
28#include "cpio_platform.h"
29__FBSDID("$FreeBSD: src/usr.bin/cpio/cmdline.c,v 1.5 2008/12/06 07:30:40 kientzle Exp $");
30
31#ifdef HAVE_ERRNO_H
32#include <errno.h>
33#endif
34#ifdef HAVE_GRP_H
35#include <grp.h>
36#endif
37#ifdef HAVE_PWD_H
38#include <pwd.h>
39#endif
40#include <stdio.h>
41#ifdef HAVE_STDLIB_H
42#include <stdlib.h>
43#endif
44#ifdef HAVE_STRING_H
45#include <string.h>
46#endif
47
48#include "cpio.h"
49#include "err.h"
50
51/*
52 * Short options for cpio.  Please keep this sorted.
53 */
54static const char *short_options = "0AaBC:cdE:F:f:H:hI:iJjLlmnO:opR:rtuvW:yZz";
55
56/*
57 * Long options for cpio.  Please keep this sorted.
58 */
59static const struct option {
60	const char *name;
61	int required;	/* 1 if this option requires an argument */
62	int equivalent;	/* Equivalent short option. */
63} cpio_longopts[] = {
64	{ "create",			0, 'o' },
65	{ "extract",			0, 'i' },
66	{ "file",			1, 'F' },
67	{ "format",             	1, 'H' },
68	{ "help",			0, 'h' },
69	{ "insecure",			0, OPTION_INSECURE },
70	{ "link",			0, 'l' },
71	{ "list",			0, 't' },
72	{ "lzma",			0, OPTION_LZMA },
73	{ "make-directories",		0, 'd' },
74	{ "no-preserve-owner",		0, OPTION_NO_PRESERVE_OWNER },
75	{ "null",			0, '0' },
76	{ "numeric-uid-gid",		0, 'n' },
77	{ "owner",			1, 'R' },
78	{ "pass-through",		0, 'p' },
79	{ "preserve-modification-time", 0, 'm' },
80	{ "preserve-owner",		0, OPTION_PRESERVE_OWNER },
81	{ "quiet",			0, OPTION_QUIET },
82	{ "unconditional",		0, 'u' },
83	{ "verbose",			0, 'v' },
84	{ "version",			0, OPTION_VERSION },
85	{ "xz",				0, 'J' },
86	{ NULL, 0, 0 }
87};
88
89/*
90 * I used to try to select platform-provided getopt() or
91 * getopt_long(), but that caused a lot of headaches.  In particular,
92 * I couldn't consistently use long options in the test harness
93 * because not all platforms have getopt_long().  That in turn led to
94 * overuse of the -W hack in the test harness, which made it rough to
95 * run the test harness against GNU cpio.  (I periodically run the
96 * test harness here against GNU cpio as a sanity-check.  Yes,
97 * I've found a couple of bugs in GNU cpio that way.)
98 */
99int
100cpio_getopt(struct cpio *cpio)
101{
102	enum { state_start = 0, state_next_word, state_short, state_long };
103	static int state = state_start;
104	static char *opt_word;
105
106	const struct option *popt, *match = NULL, *match2 = NULL;
107	const char *p, *long_prefix = "--";
108	size_t optlength;
109	int opt = '?';
110	int required = 0;
111
112	cpio->optarg = NULL;
113
114	/* First time through, initialize everything. */
115	if (state == state_start) {
116		/* Skip program name. */
117		++cpio->argv;
118		--cpio->argc;
119		state = state_next_word;
120	}
121
122	/*
123	 * We're ready to look at the next word in argv.
124	 */
125	if (state == state_next_word) {
126		/* No more arguments, so no more options. */
127		if (cpio->argv[0] == NULL)
128			return (-1);
129		/* Doesn't start with '-', so no more options. */
130		if (cpio->argv[0][0] != '-')
131			return (-1);
132		/* "--" marks end of options; consume it and return. */
133		if (strcmp(cpio->argv[0], "--") == 0) {
134			++cpio->argv;
135			--cpio->argc;
136			return (-1);
137		}
138		/* Get next word for parsing. */
139		opt_word = *cpio->argv++;
140		--cpio->argc;
141		if (opt_word[1] == '-') {
142			/* Set up long option parser. */
143			state = state_long;
144			opt_word += 2; /* Skip leading '--' */
145		} else {
146			/* Set up short option parser. */
147			state = state_short;
148			++opt_word;  /* Skip leading '-' */
149		}
150	}
151
152	/*
153	 * We're parsing a group of POSIX-style single-character options.
154	 */
155	if (state == state_short) {
156		/* Peel next option off of a group of short options. */
157		opt = *opt_word++;
158		if (opt == '\0') {
159			/* End of this group; recurse to get next option. */
160			state = state_next_word;
161			return cpio_getopt(cpio);
162		}
163
164		/* Does this option take an argument? */
165		p = strchr(short_options, opt);
166		if (p == NULL)
167			return ('?');
168		if (p[1] == ':')
169			required = 1;
170
171		/* If it takes an argument, parse that. */
172		if (required) {
173			/* If arg is run-in, opt_word already points to it. */
174			if (opt_word[0] == '\0') {
175				/* Otherwise, pick up the next word. */
176				opt_word = *cpio->argv;
177				if (opt_word == NULL) {
178					lafe_warnc(0,
179					    "Option -%c requires an argument",
180					    opt);
181					return ('?');
182				}
183				++cpio->argv;
184				--cpio->argc;
185			}
186			if (opt == 'W') {
187				state = state_long;
188				long_prefix = "-W "; /* For clearer errors. */
189			} else {
190				state = state_next_word;
191				cpio->optarg = opt_word;
192			}
193		}
194	}
195
196	/* We're reading a long option, including -W long=arg convention. */
197	if (state == state_long) {
198		/* After this long option, we'll be starting a new word. */
199		state = state_next_word;
200
201		/* Option name ends at '=' if there is one. */
202		p = strchr(opt_word, '=');
203		if (p != NULL) {
204			optlength = (size_t)(p - opt_word);
205			cpio->optarg = (char *)(uintptr_t)(p + 1);
206		} else {
207			optlength = strlen(opt_word);
208		}
209
210		/* Search the table for an unambiguous match. */
211		for (popt = cpio_longopts; popt->name != NULL; popt++) {
212			/* Short-circuit if first chars don't match. */
213			if (popt->name[0] != opt_word[0])
214				continue;
215			/* If option is a prefix of name in table, record it.*/
216			if (strncmp(opt_word, popt->name, optlength) == 0) {
217				match2 = match; /* Record up to two matches. */
218				match = popt;
219				/* If it's an exact match, we're done. */
220				if (strlen(popt->name) == optlength) {
221					match2 = NULL; /* Forget the others. */
222					break;
223				}
224			}
225		}
226
227		/* Fail if there wasn't a unique match. */
228		if (match == NULL) {
229			lafe_warnc(0,
230			    "Option %s%s is not supported",
231			    long_prefix, opt_word);
232			return ('?');
233		}
234		if (match2 != NULL) {
235			lafe_warnc(0,
236			    "Ambiguous option %s%s (matches --%s and --%s)",
237			    long_prefix, opt_word, match->name, match2->name);
238			return ('?');
239		}
240
241		/* We've found a unique match; does it need an argument? */
242		if (match->required) {
243			/* Argument required: get next word if necessary. */
244			if (cpio->optarg == NULL) {
245				cpio->optarg = *cpio->argv;
246				if (cpio->optarg == NULL) {
247					lafe_warnc(0,
248					    "Option %s%s requires an argument",
249					    long_prefix, match->name);
250					return ('?');
251				}
252				++cpio->argv;
253				--cpio->argc;
254			}
255		} else {
256			/* Argument forbidden: fail if there is one. */
257			if (cpio->optarg != NULL) {
258				lafe_warnc(0,
259				    "Option %s%s does not allow an argument",
260				    long_prefix, match->name);
261				return ('?');
262			}
263		}
264		return (match->equivalent);
265	}
266
267	return (opt);
268}
269
270
271/*
272 * Parse the argument to the -R or --owner flag.
273 *
274 * The format is one of the following:
275 *   <username|uid>    - Override user but not group
276 *   <username>:   - Override both, group is user's default group
277 *   <uid>:    - Override user but not group
278 *   <username|uid>:<groupname|gid> - Override both
279 *   :<groupname|gid>  - Override group but not user
280 *
281 * Where uid/gid are decimal representations and groupname/username
282 * are names to be looked up in system database.  Note that we try
283 * to look up an argument as a name first, then try numeric parsing.
284 *
285 * A period can be used instead of the colon.
286 *
287 * Sets uid/gid return as appropriate, -1 indicates uid/gid not specified.
288 *
289 * Returns NULL if no error, otherwise returns error string for display.
290 *
291 */
292const char *
293owner_parse(const char *spec, int *uid, int *gid)
294{
295	static char errbuff[128];
296	const char *u, *ue, *g;
297
298	*uid = -1;
299	*gid = -1;
300
301	if (spec[0] == '\0')
302		return ("Invalid empty user/group spec");
303
304	/*
305	 * Split spec into [user][:.][group]
306	 *  u -> first char of username, NULL if no username
307	 *  ue -> first char after username (colon, period, or \0)
308	 *  g -> first char of group name
309	 */
310	if (*spec == ':' || *spec == '.') {
311		/* If spec starts with ':' or '.', then just group. */
312		ue = u = NULL;
313		g = spec + 1;
314	} else {
315		/* Otherwise, [user] or [user][:] or [user][:][group] */
316		ue = u = spec;
317		while (*ue != ':' && *ue != '.' && *ue != '\0')
318			++ue;
319		g = ue;
320		if (*g != '\0') /* Skip : or . to find first char of group. */
321			++g;
322	}
323
324	if (u != NULL) {
325		/* Look up user: ue is first char after end of user. */
326		char *user;
327		struct passwd *pwent;
328
329		user = (char *)malloc(ue - u + 1);
330		if (user == NULL)
331			return ("Couldn't allocate memory");
332		memcpy(user, u, ue - u);
333		user[ue - u] = '\0';
334		if ((pwent = getpwnam(user)) != NULL) {
335			*uid = pwent->pw_uid;
336			if (*ue != '\0')
337				*gid = pwent->pw_gid;
338		} else {
339			char *end;
340			errno = 0;
341			*uid = strtoul(user, &end, 10);
342			if (errno || *end != '\0') {
343				snprintf(errbuff, sizeof(errbuff),
344				    "Couldn't lookup user ``%s''", user);
345				errbuff[sizeof(errbuff) - 1] = '\0';
346				return (errbuff);
347			}
348		}
349		free(user);
350	}
351
352	if (*g != '\0') {
353		struct group *grp;
354		if ((grp = getgrnam(g)) != NULL) {
355			*gid = grp->gr_gid;
356		} else {
357			char *end;
358			errno = 0;
359			*gid = strtoul(g, &end, 10);
360			if (errno || *end != '\0') {
361				snprintf(errbuff, sizeof(errbuff),
362				    "Couldn't lookup group ``%s''", g);
363				errbuff[sizeof(errbuff) - 1] = '\0';
364				return (errbuff);
365			}
366		}
367	}
368	return (NULL);
369}
370