xref: /dragonfly/contrib/libarchive/cpio/cmdline.c (revision 10cbe914)
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 
50 /*
51  * Short options for cpio.  Please keep this sorted.
52  */
53 static const char *short_options = "0AaBC:F:O:cdE:f:H:hI:ijLlmnopR:rtuvW:yZz";
54 
55 /*
56  * Long options for cpio.  Please keep this sorted.
57  */
58 static const struct option {
59 	const char *name;
60 	int required;	/* 1 if this option requires an argument */
61 	int equivalent;	/* Equivalent short option. */
62 } cpio_longopts[] = {
63 	{ "create",			0, 'o' },
64 	{ "extract",			0, 'i' },
65 	{ "file",			1, 'F' },
66 	{ "format",             	1, 'H' },
67 	{ "help",			0, 'h' },
68 	{ "insecure",			0, OPTION_INSECURE },
69 	{ "link",			0, 'l' },
70 	{ "list",			0, 't' },
71 	{ "make-directories",		0, 'd' },
72 	{ "no-preserve-owner",		0, OPTION_NO_PRESERVE_OWNER },
73 	{ "null",			0, '0' },
74 	{ "numeric-uid-gid",		0, 'n' },
75 	{ "owner",			1, 'R' },
76 	{ "pass-through",		0, 'p' },
77 	{ "preserve-modification-time", 0, 'm' },
78 	{ "quiet",			0, OPTION_QUIET },
79 	{ "unconditional",		0, 'u' },
80 	{ "verbose",			0, 'v' },
81 	{ "version",			0, OPTION_VERSION },
82 	{ NULL, 0, 0 }
83 };
84 
85 /*
86  * I used to try to select platform-provided getopt() or
87  * getopt_long(), but that caused a lot of headaches.  In particular,
88  * I couldn't consistently use long options in the test harness
89  * because not all platforms have getopt_long().  That in turn led to
90  * overuse of the -W hack in the test harness, which made it rough to
91  * run the test harness against GNU cpio.  (I periodically run the
92  * test harness here against GNU cpio as a sanity-check.  Yes,
93  * I've found a couple of bugs in GNU cpio that way.)
94  */
95 int
96 cpio_getopt(struct cpio *cpio)
97 {
98 	enum { state_start = 0, state_next_word, state_short, state_long };
99 	static int state = state_start;
100 	static char *opt_word;
101 
102 	const struct option *popt, *match = NULL, *match2 = NULL;
103 	const char *p, *long_prefix = "--";
104 	size_t optlength;
105 	int opt = '?';
106 	int required = 0;
107 
108 	cpio->optarg = NULL;
109 
110 	/* First time through, initialize everything. */
111 	if (state == state_start) {
112 		/* Skip program name. */
113 		++cpio->argv;
114 		--cpio->argc;
115 		state = state_next_word;
116 	}
117 
118 	/*
119 	 * We're ready to look at the next word in argv.
120 	 */
121 	if (state == state_next_word) {
122 		/* No more arguments, so no more options. */
123 		if (cpio->argv[0] == NULL)
124 			return (-1);
125 		/* Doesn't start with '-', so no more options. */
126 		if (cpio->argv[0][0] != '-')
127 			return (-1);
128 		/* "--" marks end of options; consume it and return. */
129 		if (strcmp(cpio->argv[0], "--") == 0) {
130 			++cpio->argv;
131 			--cpio->argc;
132 			return (-1);
133 		}
134 		/* Get next word for parsing. */
135 		opt_word = *cpio->argv++;
136 		--cpio->argc;
137 		if (opt_word[1] == '-') {
138 			/* Set up long option parser. */
139 			state = state_long;
140 			opt_word += 2; /* Skip leading '--' */
141 		} else {
142 			/* Set up short option parser. */
143 			state = state_short;
144 			++opt_word;  /* Skip leading '-' */
145 		}
146 	}
147 
148 	/*
149 	 * We're parsing a group of POSIX-style single-character options.
150 	 */
151 	if (state == state_short) {
152 		/* Peel next option off of a group of short options. */
153 		opt = *opt_word++;
154 		if (opt == '\0') {
155 			/* End of this group; recurse to get next option. */
156 			state = state_next_word;
157 			return cpio_getopt(cpio);
158 		}
159 
160 		/* Does this option take an argument? */
161 		p = strchr(short_options, opt);
162 		if (p == NULL)
163 			return ('?');
164 		if (p[1] == ':')
165 			required = 1;
166 
167 		/* If it takes an argument, parse that. */
168 		if (required) {
169 			/* If arg is run-in, opt_word already points to it. */
170 			if (opt_word[0] == '\0') {
171 				/* Otherwise, pick up the next word. */
172 				opt_word = *cpio->argv;
173 				if (opt_word == NULL) {
174 					cpio_warnc(0,
175 					    "Option -%c requires an argument",
176 					    opt);
177 					return ('?');
178 				}
179 				++cpio->argv;
180 				--cpio->argc;
181 			}
182 			if (opt == 'W') {
183 				state = state_long;
184 				long_prefix = "-W "; /* For clearer errors. */
185 			} else {
186 				state = state_next_word;
187 				cpio->optarg = opt_word;
188 			}
189 		}
190 	}
191 
192 	/* We're reading a long option, including -W long=arg convention. */
193 	if (state == state_long) {
194 		/* After this long option, we'll be starting a new word. */
195 		state = state_next_word;
196 
197 		/* Option name ends at '=' if there is one. */
198 		p = strchr(opt_word, '=');
199 		if (p != NULL) {
200 			optlength = (size_t)(p - opt_word);
201 			cpio->optarg = (char *)(uintptr_t)(p + 1);
202 		} else {
203 			optlength = strlen(opt_word);
204 		}
205 
206 		/* Search the table for an unambiguous match. */
207 		for (popt = cpio_longopts; popt->name != NULL; popt++) {
208 			/* Short-circuit if first chars don't match. */
209 			if (popt->name[0] != opt_word[0])
210 				continue;
211 			/* If option is a prefix of name in table, record it.*/
212 			if (strncmp(opt_word, popt->name, optlength) == 0) {
213 				match2 = match; /* Record up to two matches. */
214 				match = popt;
215 				/* If it's an exact match, we're done. */
216 				if (strlen(popt->name) == optlength) {
217 					match2 = NULL; /* Forget the others. */
218 					break;
219 				}
220 			}
221 		}
222 
223 		/* Fail if there wasn't a unique match. */
224 		if (match == NULL) {
225 			cpio_warnc(0,
226 			    "Option %s%s is not supported",
227 			    long_prefix, opt_word);
228 			return ('?');
229 		}
230 		if (match2 != NULL) {
231 			cpio_warnc(0,
232 			    "Ambiguous option %s%s (matches --%s and --%s)",
233 			    long_prefix, opt_word, match->name, match2->name);
234 			return ('?');
235 		}
236 
237 		/* We've found a unique match; does it need an argument? */
238 		if (match->required) {
239 			/* Argument required: get next word if necessary. */
240 			if (cpio->optarg == NULL) {
241 				cpio->optarg = *cpio->argv;
242 				if (cpio->optarg == NULL) {
243 					cpio_warnc(0,
244 					    "Option %s%s requires an argument",
245 					    long_prefix, match->name);
246 					return ('?');
247 				}
248 				++cpio->argv;
249 				--cpio->argc;
250 			}
251 		} else {
252 			/* Argument forbidden: fail if there is one. */
253 			if (cpio->optarg != NULL) {
254 				cpio_warnc(0,
255 				    "Option %s%s does not allow an argument",
256 				    long_prefix, match->name);
257 				return ('?');
258 			}
259 		}
260 		return (match->equivalent);
261 	}
262 
263 	return (opt);
264 }
265 
266 
267 /*
268  * Parse the argument to the -R or --owner flag.
269  *
270  * The format is one of the following:
271  *   <user>    - Override user but not group
272  *   <user>:   - Override both, group is user's default group
273  *   <user>:<group> - Override both
274  *   :<group>  - Override group but not user
275  *
276  * A period can be used instead of the colon.
277  *
278  * Sets uid/gid as appropriate, -1 indicates uid/gid not specified.
279  *
280  */
281 int
282 owner_parse(const char *spec, int *uid, int *gid)
283 {
284 	const char *u, *ue, *g;
285 
286 	*uid = -1;
287 	*gid = -1;
288 
289 	/*
290 	 * Split spec into [user][:.][group]
291 	 *  u -> first char of username, NULL if no username
292 	 *  ue -> first char after username (colon, period, or \0)
293 	 *  g -> first char of group name
294 	 */
295 	if (*spec == ':' || *spec == '.') {
296 		/* If spec starts with ':' or '.', then just group. */
297 		ue = u = NULL;
298 		g = spec + 1;
299 	} else {
300 		/* Otherwise, [user] or [user][:] or [user][:][group] */
301 		ue = u = spec;
302 		while (*ue != ':' && *ue != '.' && *ue != '\0')
303 			++ue;
304 		g = ue;
305 		if (*g != '\0') /* Skip : or . to find first char of group. */
306 			++g;
307 	}
308 
309 	if (u != NULL) {
310 		/* Look up user: ue is first char after end of user. */
311 		char *user;
312 		struct passwd *pwent;
313 
314 		user = (char *)malloc(ue - u + 1);
315 		if (user == NULL) {
316 			cpio_warnc(errno, "Couldn't allocate memory");
317 			return (1);
318 		}
319 		memcpy(user, u, ue - u);
320 		user[ue - u] = '\0';
321 		pwent = getpwnam(user);
322 		if (pwent == NULL) {
323 			cpio_warnc(errno, "Couldn't lookup user ``%s''", user);
324 			return (1);
325 		}
326 		free(user);
327 		*uid = pwent->pw_uid;
328 		if (*ue != '\0' && *g == '\0')
329 			*gid = pwent->pw_gid;
330 	}
331 	if (*g != '\0') {
332 		struct group *grp;
333 		grp = getgrnam(g);
334 		if (grp != NULL)
335 			*gid = grp->gr_gid;
336 		else {
337 			cpio_warnc(errno, "Couldn't look up group ``%s''", g);
338 			return (1);
339 		}
340 	}
341 	return (0);
342 }
343