xref: /freebsd/contrib/libarchive/cpio/cmdline.c (revision 273c26a3c3bea87a241d6879abd4f991db180bf0)
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("$FreeBSD$");
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  */
54 static const char *short_options = "0AaBC:cdE:F:f:H:hI:iJjLlmnO:opR:rtuVvW:yZz";
55 
56 /*
57  * Long options for cpio.  Please keep this sorted.
58  */
59 static 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 	{ "b64encode",			0, OPTION_B64ENCODE },
65 	{ "create",			0, 'o' },
66 	{ "dereference",		0, 'L' },
67 	{ "dot",			0, 'V' },
68 	{ "extract",			0, 'i' },
69 	{ "file",			1, 'F' },
70 	{ "format",             	1, 'H' },
71 	{ "grzip",			0, OPTION_GRZIP },
72 	{ "help",			0, 'h' },
73 	{ "insecure",			0, OPTION_INSECURE },
74 	{ "link",			0, 'l' },
75 	{ "list",			0, 't' },
76 	{ "lrzip",			0, OPTION_LRZIP },
77 	{ "lz4",			0, OPTION_LZ4 },
78 	{ "lzma",			0, OPTION_LZMA },
79 	{ "lzop",			0, OPTION_LZOP },
80 	{ "make-directories",		0, 'd' },
81 	{ "no-preserve-owner",		0, OPTION_NO_PRESERVE_OWNER },
82 	{ "null",			0, '0' },
83 	{ "numeric-uid-gid",		0, 'n' },
84 	{ "owner",			1, 'R' },
85 	{ "passphrase",			1, OPTION_PASSPHRASE },
86 	{ "pass-through",		0, 'p' },
87 	{ "preserve-modification-time", 0, 'm' },
88 	{ "preserve-owner",		0, OPTION_PRESERVE_OWNER },
89 	{ "quiet",			0, OPTION_QUIET },
90 	{ "unconditional",		0, 'u' },
91 	{ "uuencode",			0, OPTION_UUENCODE },
92 	{ "verbose",			0, 'v' },
93 	{ "version",			0, OPTION_VERSION },
94 	{ "xz",				0, 'J' },
95 	{ NULL, 0, 0 }
96 };
97 
98 /*
99  * I used to try to select platform-provided getopt() or
100  * getopt_long(), but that caused a lot of headaches.  In particular,
101  * I couldn't consistently use long options in the test harness
102  * because not all platforms have getopt_long().  That in turn led to
103  * overuse of the -W hack in the test harness, which made it rough to
104  * run the test harness against GNU cpio.  (I periodically run the
105  * test harness here against GNU cpio as a sanity-check.  Yes,
106  * I've found a couple of bugs in GNU cpio that way.)
107  */
108 int
109 cpio_getopt(struct cpio *cpio)
110 {
111 	enum { state_start = 0, state_next_word, state_short, state_long };
112 	static int state = state_start;
113 	static char *opt_word;
114 
115 	const struct option *popt, *match = NULL, *match2 = NULL;
116 	const char *p, *long_prefix = "--";
117 	size_t optlength;
118 	int opt = '?';
119 	int required = 0;
120 
121 	cpio->argument = NULL;
122 
123 	/* First time through, initialize everything. */
124 	if (state == state_start) {
125 		/* Skip program name. */
126 		++cpio->argv;
127 		--cpio->argc;
128 		state = state_next_word;
129 	}
130 
131 	/*
132 	 * We're ready to look at the next word in argv.
133 	 */
134 	if (state == state_next_word) {
135 		/* No more arguments, so no more options. */
136 		if (cpio->argv[0] == NULL)
137 			return (-1);
138 		/* Doesn't start with '-', so no more options. */
139 		if (cpio->argv[0][0] != '-')
140 			return (-1);
141 		/* "--" marks end of options; consume it and return. */
142 		if (strcmp(cpio->argv[0], "--") == 0) {
143 			++cpio->argv;
144 			--cpio->argc;
145 			return (-1);
146 		}
147 		/* Get next word for parsing. */
148 		opt_word = *cpio->argv++;
149 		--cpio->argc;
150 		if (opt_word[1] == '-') {
151 			/* Set up long option parser. */
152 			state = state_long;
153 			opt_word += 2; /* Skip leading '--' */
154 		} else {
155 			/* Set up short option parser. */
156 			state = state_short;
157 			++opt_word;  /* Skip leading '-' */
158 		}
159 	}
160 
161 	/*
162 	 * We're parsing a group of POSIX-style single-character options.
163 	 */
164 	if (state == state_short) {
165 		/* Peel next option off of a group of short options. */
166 		opt = *opt_word++;
167 		if (opt == '\0') {
168 			/* End of this group; recurse to get next option. */
169 			state = state_next_word;
170 			return cpio_getopt(cpio);
171 		}
172 
173 		/* Does this option take an argument? */
174 		p = strchr(short_options, opt);
175 		if (p == NULL)
176 			return ('?');
177 		if (p[1] == ':')
178 			required = 1;
179 
180 		/* If it takes an argument, parse that. */
181 		if (required) {
182 			/* If arg is run-in, opt_word already points to it. */
183 			if (opt_word[0] == '\0') {
184 				/* Otherwise, pick up the next word. */
185 				opt_word = *cpio->argv;
186 				if (opt_word == NULL) {
187 					lafe_warnc(0,
188 					    "Option -%c requires an argument",
189 					    opt);
190 					return ('?');
191 				}
192 				++cpio->argv;
193 				--cpio->argc;
194 			}
195 			if (opt == 'W') {
196 				state = state_long;
197 				long_prefix = "-W "; /* For clearer errors. */
198 			} else {
199 				state = state_next_word;
200 				cpio->argument = opt_word;
201 			}
202 		}
203 	}
204 
205 	/* We're reading a long option, including -W long=arg convention. */
206 	if (state == state_long) {
207 		/* After this long option, we'll be starting a new word. */
208 		state = state_next_word;
209 
210 		/* Option name ends at '=' if there is one. */
211 		p = strchr(opt_word, '=');
212 		if (p != NULL) {
213 			optlength = (size_t)(p - opt_word);
214 			cpio->argument = (char *)(uintptr_t)(p + 1);
215 		} else {
216 			optlength = strlen(opt_word);
217 		}
218 
219 		/* Search the table for an unambiguous match. */
220 		for (popt = cpio_longopts; popt->name != NULL; popt++) {
221 			/* Short-circuit if first chars don't match. */
222 			if (popt->name[0] != opt_word[0])
223 				continue;
224 			/* If option is a prefix of name in table, record it.*/
225 			if (strncmp(opt_word, popt->name, optlength) == 0) {
226 				match2 = match; /* Record up to two matches. */
227 				match = popt;
228 				/* If it's an exact match, we're done. */
229 				if (strlen(popt->name) == optlength) {
230 					match2 = NULL; /* Forget the others. */
231 					break;
232 				}
233 			}
234 		}
235 
236 		/* Fail if there wasn't a unique match. */
237 		if (match == NULL) {
238 			lafe_warnc(0,
239 			    "Option %s%s is not supported",
240 			    long_prefix, opt_word);
241 			return ('?');
242 		}
243 		if (match2 != NULL) {
244 			lafe_warnc(0,
245 			    "Ambiguous option %s%s (matches --%s and --%s)",
246 			    long_prefix, opt_word, match->name, match2->name);
247 			return ('?');
248 		}
249 
250 		/* We've found a unique match; does it need an argument? */
251 		if (match->required) {
252 			/* Argument required: get next word if necessary. */
253 			if (cpio->argument == NULL) {
254 				cpio->argument = *cpio->argv;
255 				if (cpio->argument == NULL) {
256 					lafe_warnc(0,
257 					    "Option %s%s requires an argument",
258 					    long_prefix, match->name);
259 					return ('?');
260 				}
261 				++cpio->argv;
262 				--cpio->argc;
263 			}
264 		} else {
265 			/* Argument forbidden: fail if there is one. */
266 			if (cpio->argument != NULL) {
267 				lafe_warnc(0,
268 				    "Option %s%s does not allow an argument",
269 				    long_prefix, match->name);
270 				return ('?');
271 			}
272 		}
273 		return (match->equivalent);
274 	}
275 
276 	return (opt);
277 }
278 
279 
280 /*
281  * Parse the argument to the -R or --owner flag.
282  *
283  * The format is one of the following:
284  *   <username|uid>    - Override user but not group
285  *   <username>:   - Override both, group is user's default group
286  *   <uid>:    - Override user but not group
287  *   <username|uid>:<groupname|gid> - Override both
288  *   :<groupname|gid>  - Override group but not user
289  *
290  * Where uid/gid are decimal representations and groupname/username
291  * are names to be looked up in system database.  Note that we try
292  * to look up an argument as a name first, then try numeric parsing.
293  *
294  * A period can be used instead of the colon.
295  *
296  * Sets uid/gid return as appropriate, -1 indicates uid/gid not specified.
297  * TODO: If the spec uses uname/gname, then return those to the caller
298  * as well.  If the spec provides uid/gid, just return names as NULL.
299  *
300  * Returns NULL if no error, otherwise returns error string for display.
301  *
302  */
303 const char *
304 owner_parse(const char *spec, int *uid, int *gid)
305 {
306 	static char errbuff[128];
307 	const char *u, *ue, *g;
308 
309 	*uid = -1;
310 	*gid = -1;
311 
312 	if (spec[0] == '\0')
313 		return ("Invalid empty user/group spec");
314 
315 	/*
316 	 * Split spec into [user][:.][group]
317 	 *  u -> first char of username, NULL if no username
318 	 *  ue -> first char after username (colon, period, or \0)
319 	 *  g -> first char of group name
320 	 */
321 	if (*spec == ':' || *spec == '.') {
322 		/* If spec starts with ':' or '.', then just group. */
323 		ue = u = NULL;
324 		g = spec + 1;
325 	} else {
326 		/* Otherwise, [user] or [user][:] or [user][:][group] */
327 		ue = u = spec;
328 		while (*ue != ':' && *ue != '.' && *ue != '\0')
329 			++ue;
330 		g = ue;
331 		if (*g != '\0') /* Skip : or . to find first char of group. */
332 			++g;
333 	}
334 
335 	if (u != NULL) {
336 		/* Look up user: ue is first char after end of user. */
337 		char *user;
338 		struct passwd *pwent;
339 
340 		user = (char *)malloc(ue - u + 1);
341 		if (user == NULL)
342 			return ("Couldn't allocate memory");
343 		memcpy(user, u, ue - u);
344 		user[ue - u] = '\0';
345 		if ((pwent = getpwnam(user)) != NULL) {
346 			*uid = pwent->pw_uid;
347 			if (*ue != '\0')
348 				*gid = pwent->pw_gid;
349 		} else {
350 			char *end;
351 			errno = 0;
352 			*uid = (int)strtoul(user, &end, 10);
353 			if (errno || *end != '\0') {
354 				snprintf(errbuff, sizeof(errbuff),
355 				    "Couldn't lookup user ``%s''", user);
356 				errbuff[sizeof(errbuff) - 1] = '\0';
357 				free(user);
358 				return (errbuff);
359 			}
360 		}
361 		free(user);
362 	}
363 
364 	if (*g != '\0') {
365 		struct group *grp;
366 		if ((grp = getgrnam(g)) != NULL) {
367 			*gid = grp->gr_gid;
368 		} else {
369 			char *end;
370 			errno = 0;
371 			*gid = (int)strtoul(g, &end, 10);
372 			if (errno || *end != '\0') {
373 				snprintf(errbuff, sizeof(errbuff),
374 				    "Couldn't lookup group ``%s''", g);
375 				errbuff[sizeof(errbuff) - 1] = '\0';
376 				return (errbuff);
377 			}
378 		}
379 	}
380 	return (NULL);
381 }
382