xref: /freebsd/contrib/libarchive/cpio/cmdline.c (revision b9dee1dca2d74e12e867fd29d2d584fc385078eb)
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 
30 #ifdef HAVE_ERRNO_H
31 #include <errno.h>
32 #endif
33 #ifdef HAVE_GRP_H
34 #include <grp.h>
35 #endif
36 #ifdef HAVE_PWD_H
37 #include <pwd.h>
38 #endif
39 #include <stdio.h>
40 #ifdef HAVE_STDLIB_H
41 #include <stdlib.h>
42 #endif
43 #ifdef HAVE_STRING_H
44 #include <string.h>
45 #endif
46 
47 #include "cpio.h"
48 #include "err.h"
49 
50 /*
51  * Short options for cpio.  Please keep this sorted.
52  */
53 static const char *short_options = "067AaBC:cdE:F:f:H:hI:iJjLlmnO:opR:rtuVvW: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 	{ "b64encode",			0, OPTION_B64ENCODE },
64 	{ "binary",			0, '7' },
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 	{ "pwb",			0, '6' },
90 	{ "quiet",			0, OPTION_QUIET },
91 	{ "unconditional",		0, 'u' },
92 	{ "uuencode",			0, OPTION_UUENCODE },
93 	{ "verbose",			0, 'v' },
94 	{ "version",			0, OPTION_VERSION },
95 	{ "xz",				0, 'J' },
96 	{ "zstd",			0, OPTION_ZSTD },
97 	{ NULL, 0, 0 }
98 };
99 
100 /*
101  * I used to try to select platform-provided getopt() or
102  * getopt_long(), but that caused a lot of headaches.  In particular,
103  * I couldn't consistently use long options in the test harness
104  * because not all platforms have getopt_long().  That in turn led to
105  * overuse of the -W hack in the test harness, which made it rough to
106  * run the test harness against GNU cpio.  (I periodically run the
107  * test harness here against GNU cpio as a sanity-check.  Yes,
108  * I've found a couple of bugs in GNU cpio that way.)
109  */
110 int
111 cpio_getopt(struct cpio *cpio)
112 {
113 	enum { state_start = 0, state_next_word, state_short, state_long };
114 	static int state = state_start;
115 	static char *opt_word;
116 
117 	const struct option *popt, *match = NULL, *match2 = NULL;
118 	const char *p, *long_prefix = "--";
119 	size_t optlength;
120 	int opt = '?';
121 	int required = 0;
122 
123 	cpio->argument = NULL;
124 
125 	/* First time through, initialize everything. */
126 	if (state == state_start) {
127 		/* Skip program name. */
128 		++cpio->argv;
129 		--cpio->argc;
130 		state = state_next_word;
131 	}
132 
133 	/*
134 	 * We're ready to look at the next word in argv.
135 	 */
136 	if (state == state_next_word) {
137 		/* No more arguments, so no more options. */
138 		if (cpio->argv[0] == NULL)
139 			return (-1);
140 		/* Doesn't start with '-', so no more options. */
141 		if (cpio->argv[0][0] != '-')
142 			return (-1);
143 		/* "--" marks end of options; consume it and return. */
144 		if (strcmp(cpio->argv[0], "--") == 0) {
145 			++cpio->argv;
146 			--cpio->argc;
147 			return (-1);
148 		}
149 		/* Get next word for parsing. */
150 		opt_word = *cpio->argv++;
151 		--cpio->argc;
152 		if (opt_word[1] == '-') {
153 			/* Set up long option parser. */
154 			state = state_long;
155 			opt_word += 2; /* Skip leading '--' */
156 		} else {
157 			/* Set up short option parser. */
158 			state = state_short;
159 			++opt_word;  /* Skip leading '-' */
160 		}
161 	}
162 
163 	/*
164 	 * We're parsing a group of POSIX-style single-character options.
165 	 */
166 	if (state == state_short) {
167 		/* Peel next option off of a group of short options. */
168 		opt = *opt_word++;
169 		if (opt == '\0') {
170 			/* End of this group; recurse to get next option. */
171 			state = state_next_word;
172 			return cpio_getopt(cpio);
173 		}
174 
175 		/* Does this option take an argument? */
176 		p = strchr(short_options, opt);
177 		if (p == NULL)
178 			return ('?');
179 		if (p[1] == ':')
180 			required = 1;
181 
182 		/* If it takes an argument, parse that. */
183 		if (required) {
184 			/* If arg is run-in, opt_word already points to it. */
185 			if (opt_word[0] == '\0') {
186 				/* Otherwise, pick up the next word. */
187 				opt_word = *cpio->argv;
188 				if (opt_word == NULL) {
189 					lafe_warnc(0,
190 					    "Option -%c requires an argument",
191 					    opt);
192 					return ('?');
193 				}
194 				++cpio->argv;
195 				--cpio->argc;
196 			}
197 			if (opt == 'W') {
198 				state = state_long;
199 				long_prefix = "-W "; /* For clearer errors. */
200 			} else {
201 				state = state_next_word;
202 				cpio->argument = opt_word;
203 			}
204 		}
205 	}
206 
207 	/* We're reading a long option, including -W long=arg convention. */
208 	if (state == state_long) {
209 		/* After this long option, we'll be starting a new word. */
210 		state = state_next_word;
211 
212 		/* Option name ends at '=' if there is one. */
213 		p = strchr(opt_word, '=');
214 		if (p != NULL) {
215 			optlength = (size_t)(p - opt_word);
216 			cpio->argument = (char *)(uintptr_t)(p + 1);
217 		} else {
218 			optlength = strlen(opt_word);
219 		}
220 
221 		/* Search the table for an unambiguous match. */
222 		for (popt = cpio_longopts; popt->name != NULL; popt++) {
223 			/* Short-circuit if first chars don't match. */
224 			if (popt->name[0] != opt_word[0])
225 				continue;
226 			/* If option is a prefix of name in table, record it.*/
227 			if (strncmp(opt_word, popt->name, optlength) == 0) {
228 				match2 = match; /* Record up to two matches. */
229 				match = popt;
230 				/* If it's an exact match, we're done. */
231 				if (strlen(popt->name) == optlength) {
232 					match2 = NULL; /* Forget the others. */
233 					break;
234 				}
235 			}
236 		}
237 
238 		/* Fail if there wasn't a unique match. */
239 		if (match == NULL) {
240 			lafe_warnc(0,
241 			    "Option %s%s is not supported",
242 			    long_prefix, opt_word);
243 			return ('?');
244 		}
245 		if (match2 != NULL) {
246 			lafe_warnc(0,
247 			    "Ambiguous option %s%s (matches --%s and --%s)",
248 			    long_prefix, opt_word, match->name, match2->name);
249 			return ('?');
250 		}
251 
252 		/* We've found a unique match; does it need an argument? */
253 		if (match->required) {
254 			/* Argument required: get next word if necessary. */
255 			if (cpio->argument == NULL) {
256 				cpio->argument = *cpio->argv;
257 				if (cpio->argument == NULL) {
258 					lafe_warnc(0,
259 					    "Option %s%s requires an argument",
260 					    long_prefix, match->name);
261 					return ('?');
262 				}
263 				++cpio->argv;
264 				--cpio->argc;
265 			}
266 		} else {
267 			/* Argument forbidden: fail if there is one. */
268 			if (cpio->argument != NULL) {
269 				lafe_warnc(0,
270 				    "Option %s%s does not allow an argument",
271 				    long_prefix, match->name);
272 				return ('?');
273 			}
274 		}
275 		return (match->equivalent);
276 	}
277 
278 	return (opt);
279 }
280 
281 
282 /*
283  * Parse the argument to the -R or --owner flag.
284  *
285  * The format is one of the following:
286  *   <username|uid>    - Override user but not group
287  *   <username>:   - Override both, group is user's default group
288  *   <uid>:    - Override user but not group
289  *   <username|uid>:<groupname|gid> - Override both
290  *   :<groupname|gid>  - Override group but not user
291  *
292  * Where uid/gid are decimal representations and groupname/username
293  * are names to be looked up in system database.  Note that we try
294  * to look up an argument as a name first, then try numeric parsing.
295  *
296  * A period can be used instead of the colon.
297  *
298  * Sets uid/gid return as appropriate, -1 indicates uid/gid not specified.
299  * TODO: If the spec uses uname/gname, then return those to the caller
300  * as well.  If the spec provides uid/gid, just return names as NULL.
301  *
302  * Returns NULL if no error, otherwise returns error string for display.
303  *
304  */
305 const char *
306 owner_parse(const char *spec, int *uid, int *gid)
307 {
308 	static char errbuff[128];
309 	const char *u, *ue, *g;
310 
311 	*uid = -1;
312 	*gid = -1;
313 
314 	if (spec[0] == '\0')
315 		return ("Invalid empty user/group spec");
316 
317 	/*
318 	 * Split spec into [user][:.][group]
319 	 *  u -> first char of username, NULL if no username
320 	 *  ue -> first char after username (colon, period, or \0)
321 	 *  g -> first char of group name
322 	 */
323 	if (*spec == ':' || *spec == '.') {
324 		/* If spec starts with ':' or '.', then just group. */
325 		ue = u = NULL;
326 		g = spec + 1;
327 	} else {
328 		/* Otherwise, [user] or [user][:] or [user][:][group] */
329 		ue = u = spec;
330 		while (*ue != ':' && *ue != '.' && *ue != '\0')
331 			++ue;
332 		g = ue;
333 		if (*g != '\0') /* Skip : or . to find first char of group. */
334 			++g;
335 	}
336 
337 	if (u != NULL) {
338 		/* Look up user: ue is first char after end of user. */
339 		char *user;
340 		struct passwd *pwent;
341 
342 		user = (char *)malloc(ue - u + 1);
343 		if (user == NULL)
344 			return ("Couldn't allocate memory");
345 		memcpy(user, u, ue - u);
346 		user[ue - u] = '\0';
347 		if ((pwent = getpwnam(user)) != NULL) {
348 			*uid = pwent->pw_uid;
349 			if (*ue != '\0')
350 				*gid = pwent->pw_gid;
351 		} else {
352 			char *end;
353 			errno = 0;
354 			*uid = (int)strtoul(user, &end, 10);
355 			if (errno || *end != '\0') {
356 				snprintf(errbuff, sizeof(errbuff),
357 				    "Couldn't lookup user ``%s''", user);
358 				errbuff[sizeof(errbuff) - 1] = '\0';
359 				free(user);
360 				return (errbuff);
361 			}
362 		}
363 		free(user);
364 	}
365 
366 	if (*g != '\0') {
367 		struct group *grp;
368 		if ((grp = getgrnam(g)) != NULL) {
369 			*gid = grp->gr_gid;
370 		} else {
371 			char *end;
372 			errno = 0;
373 			*gid = (int)strtoul(g, &end, 10);
374 			if (errno || *end != '\0') {
375 				snprintf(errbuff, sizeof(errbuff),
376 				    "Couldn't lookup group ``%s''", g);
377 				errbuff[sizeof(errbuff) - 1] = '\0';
378 				return (errbuff);
379 			}
380 		}
381 	}
382 	return (NULL);
383 }
384