xref: /freebsd/contrib/libarchive/cpio/cmdline.c (revision fe6060f10f634930ff71b7c50291ddc610da2475)
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 = "067AaBC: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 	{ "binary",			0, '7' },
66 	{ "create",			0, 'o' },
67 	{ "dereference",		0, 'L' },
68 	{ "dot",			0, 'V' },
69 	{ "extract",			0, 'i' },
70 	{ "file",			1, 'F' },
71 	{ "format",             	1, 'H' },
72 	{ "grzip",			0, OPTION_GRZIP },
73 	{ "help",			0, 'h' },
74 	{ "insecure",			0, OPTION_INSECURE },
75 	{ "link",			0, 'l' },
76 	{ "list",			0, 't' },
77 	{ "lrzip",			0, OPTION_LRZIP },
78 	{ "lz4",			0, OPTION_LZ4 },
79 	{ "lzma",			0, OPTION_LZMA },
80 	{ "lzop",			0, OPTION_LZOP },
81 	{ "make-directories",		0, 'd' },
82 	{ "no-preserve-owner",		0, OPTION_NO_PRESERVE_OWNER },
83 	{ "null",			0, '0' },
84 	{ "numeric-uid-gid",		0, 'n' },
85 	{ "owner",			1, 'R' },
86 	{ "passphrase",			1, OPTION_PASSPHRASE },
87 	{ "pass-through",		0, 'p' },
88 	{ "preserve-modification-time", 0, 'm' },
89 	{ "preserve-owner",		0, OPTION_PRESERVE_OWNER },
90 	{ "pwb",			0, '6' },
91 	{ "quiet",			0, OPTION_QUIET },
92 	{ "unconditional",		0, 'u' },
93 	{ "uuencode",			0, OPTION_UUENCODE },
94 	{ "verbose",			0, 'v' },
95 	{ "version",			0, OPTION_VERSION },
96 	{ "xz",				0, 'J' },
97 	{ "zstd",			0, OPTION_ZSTD },
98 	{ NULL, 0, 0 }
99 };
100 
101 /*
102  * I used to try to select platform-provided getopt() or
103  * getopt_long(), but that caused a lot of headaches.  In particular,
104  * I couldn't consistently use long options in the test harness
105  * because not all platforms have getopt_long().  That in turn led to
106  * overuse of the -W hack in the test harness, which made it rough to
107  * run the test harness against GNU cpio.  (I periodically run the
108  * test harness here against GNU cpio as a sanity-check.  Yes,
109  * I've found a couple of bugs in GNU cpio that way.)
110  */
111 int
112 cpio_getopt(struct cpio *cpio)
113 {
114 	enum { state_start = 0, state_next_word, state_short, state_long };
115 	static int state = state_start;
116 	static char *opt_word;
117 
118 	const struct option *popt, *match = NULL, *match2 = NULL;
119 	const char *p, *long_prefix = "--";
120 	size_t optlength;
121 	int opt = '?';
122 	int required = 0;
123 
124 	cpio->argument = NULL;
125 
126 	/* First time through, initialize everything. */
127 	if (state == state_start) {
128 		/* Skip program name. */
129 		++cpio->argv;
130 		--cpio->argc;
131 		state = state_next_word;
132 	}
133 
134 	/*
135 	 * We're ready to look at the next word in argv.
136 	 */
137 	if (state == state_next_word) {
138 		/* No more arguments, so no more options. */
139 		if (cpio->argv[0] == NULL)
140 			return (-1);
141 		/* Doesn't start with '-', so no more options. */
142 		if (cpio->argv[0][0] != '-')
143 			return (-1);
144 		/* "--" marks end of options; consume it and return. */
145 		if (strcmp(cpio->argv[0], "--") == 0) {
146 			++cpio->argv;
147 			--cpio->argc;
148 			return (-1);
149 		}
150 		/* Get next word for parsing. */
151 		opt_word = *cpio->argv++;
152 		--cpio->argc;
153 		if (opt_word[1] == '-') {
154 			/* Set up long option parser. */
155 			state = state_long;
156 			opt_word += 2; /* Skip leading '--' */
157 		} else {
158 			/* Set up short option parser. */
159 			state = state_short;
160 			++opt_word;  /* Skip leading '-' */
161 		}
162 	}
163 
164 	/*
165 	 * We're parsing a group of POSIX-style single-character options.
166 	 */
167 	if (state == state_short) {
168 		/* Peel next option off of a group of short options. */
169 		opt = *opt_word++;
170 		if (opt == '\0') {
171 			/* End of this group; recurse to get next option. */
172 			state = state_next_word;
173 			return cpio_getopt(cpio);
174 		}
175 
176 		/* Does this option take an argument? */
177 		p = strchr(short_options, opt);
178 		if (p == NULL)
179 			return ('?');
180 		if (p[1] == ':')
181 			required = 1;
182 
183 		/* If it takes an argument, parse that. */
184 		if (required) {
185 			/* If arg is run-in, opt_word already points to it. */
186 			if (opt_word[0] == '\0') {
187 				/* Otherwise, pick up the next word. */
188 				opt_word = *cpio->argv;
189 				if (opt_word == NULL) {
190 					lafe_warnc(0,
191 					    "Option -%c requires an argument",
192 					    opt);
193 					return ('?');
194 				}
195 				++cpio->argv;
196 				--cpio->argc;
197 			}
198 			if (opt == 'W') {
199 				state = state_long;
200 				long_prefix = "-W "; /* For clearer errors. */
201 			} else {
202 				state = state_next_word;
203 				cpio->argument = opt_word;
204 			}
205 		}
206 	}
207 
208 	/* We're reading a long option, including -W long=arg convention. */
209 	if (state == state_long) {
210 		/* After this long option, we'll be starting a new word. */
211 		state = state_next_word;
212 
213 		/* Option name ends at '=' if there is one. */
214 		p = strchr(opt_word, '=');
215 		if (p != NULL) {
216 			optlength = (size_t)(p - opt_word);
217 			cpio->argument = (char *)(uintptr_t)(p + 1);
218 		} else {
219 			optlength = strlen(opt_word);
220 		}
221 
222 		/* Search the table for an unambiguous match. */
223 		for (popt = cpio_longopts; popt->name != NULL; popt++) {
224 			/* Short-circuit if first chars don't match. */
225 			if (popt->name[0] != opt_word[0])
226 				continue;
227 			/* If option is a prefix of name in table, record it.*/
228 			if (strncmp(opt_word, popt->name, optlength) == 0) {
229 				match2 = match; /* Record up to two matches. */
230 				match = popt;
231 				/* If it's an exact match, we're done. */
232 				if (strlen(popt->name) == optlength) {
233 					match2 = NULL; /* Forget the others. */
234 					break;
235 				}
236 			}
237 		}
238 
239 		/* Fail if there wasn't a unique match. */
240 		if (match == NULL) {
241 			lafe_warnc(0,
242 			    "Option %s%s is not supported",
243 			    long_prefix, opt_word);
244 			return ('?');
245 		}
246 		if (match2 != NULL) {
247 			lafe_warnc(0,
248 			    "Ambiguous option %s%s (matches --%s and --%s)",
249 			    long_prefix, opt_word, match->name, match2->name);
250 			return ('?');
251 		}
252 
253 		/* We've found a unique match; does it need an argument? */
254 		if (match->required) {
255 			/* Argument required: get next word if necessary. */
256 			if (cpio->argument == NULL) {
257 				cpio->argument = *cpio->argv;
258 				if (cpio->argument == NULL) {
259 					lafe_warnc(0,
260 					    "Option %s%s requires an argument",
261 					    long_prefix, match->name);
262 					return ('?');
263 				}
264 				++cpio->argv;
265 				--cpio->argc;
266 			}
267 		} else {
268 			/* Argument forbidden: fail if there is one. */
269 			if (cpio->argument != NULL) {
270 				lafe_warnc(0,
271 				    "Option %s%s does not allow an argument",
272 				    long_prefix, match->name);
273 				return ('?');
274 			}
275 		}
276 		return (match->equivalent);
277 	}
278 
279 	return (opt);
280 }
281 
282 
283 /*
284  * Parse the argument to the -R or --owner flag.
285  *
286  * The format is one of the following:
287  *   <username|uid>    - Override user but not group
288  *   <username>:   - Override both, group is user's default group
289  *   <uid>:    - Override user but not group
290  *   <username|uid>:<groupname|gid> - Override both
291  *   :<groupname|gid>  - Override group but not user
292  *
293  * Where uid/gid are decimal representations and groupname/username
294  * are names to be looked up in system database.  Note that we try
295  * to look up an argument as a name first, then try numeric parsing.
296  *
297  * A period can be used instead of the colon.
298  *
299  * Sets uid/gid return as appropriate, -1 indicates uid/gid not specified.
300  * TODO: If the spec uses uname/gname, then return those to the caller
301  * as well.  If the spec provides uid/gid, just return names as NULL.
302  *
303  * Returns NULL if no error, otherwise returns error string for display.
304  *
305  */
306 const char *
307 owner_parse(const char *spec, int *uid, int *gid)
308 {
309 	static char errbuff[128];
310 	const char *u, *ue, *g;
311 
312 	*uid = -1;
313 	*gid = -1;
314 
315 	if (spec[0] == '\0')
316 		return ("Invalid empty user/group spec");
317 
318 	/*
319 	 * Split spec into [user][:.][group]
320 	 *  u -> first char of username, NULL if no username
321 	 *  ue -> first char after username (colon, period, or \0)
322 	 *  g -> first char of group name
323 	 */
324 	if (*spec == ':' || *spec == '.') {
325 		/* If spec starts with ':' or '.', then just group. */
326 		ue = u = NULL;
327 		g = spec + 1;
328 	} else {
329 		/* Otherwise, [user] or [user][:] or [user][:][group] */
330 		ue = u = spec;
331 		while (*ue != ':' && *ue != '.' && *ue != '\0')
332 			++ue;
333 		g = ue;
334 		if (*g != '\0') /* Skip : or . to find first char of group. */
335 			++g;
336 	}
337 
338 	if (u != NULL) {
339 		/* Look up user: ue is first char after end of user. */
340 		char *user;
341 		struct passwd *pwent;
342 
343 		user = (char *)malloc(ue - u + 1);
344 		if (user == NULL)
345 			return ("Couldn't allocate memory");
346 		memcpy(user, u, ue - u);
347 		user[ue - u] = '\0';
348 		if ((pwent = getpwnam(user)) != NULL) {
349 			*uid = pwent->pw_uid;
350 			if (*ue != '\0')
351 				*gid = pwent->pw_gid;
352 		} else {
353 			char *end;
354 			errno = 0;
355 			*uid = (int)strtoul(user, &end, 10);
356 			if (errno || *end != '\0') {
357 				snprintf(errbuff, sizeof(errbuff),
358 				    "Couldn't lookup user ``%s''", user);
359 				errbuff[sizeof(errbuff) - 1] = '\0';
360 				free(user);
361 				return (errbuff);
362 			}
363 		}
364 		free(user);
365 	}
366 
367 	if (*g != '\0') {
368 		struct group *grp;
369 		if ((grp = getgrnam(g)) != NULL) {
370 			*gid = grp->gr_gid;
371 		} else {
372 			char *end;
373 			errno = 0;
374 			*gid = (int)strtoul(g, &end, 10);
375 			if (errno || *end != '\0') {
376 				snprintf(errbuff, sizeof(errbuff),
377 				    "Couldn't lookup group ``%s''", g);
378 				errbuff[sizeof(errbuff) - 1] = '\0';
379 				return (errbuff);
380 			}
381 		}
382 	}
383 	return (NULL);
384 }
385