xref: /freebsd/contrib/libarchive/cpio/cmdline.c (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
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 	{ "dot",			0, 'V' },
67 	{ "extract",			0, 'i' },
68 	{ "file",			1, 'F' },
69 	{ "format",             	1, 'H' },
70 	{ "grzip",			0, OPTION_GRZIP },
71 	{ "help",			0, 'h' },
72 	{ "insecure",			0, OPTION_INSECURE },
73 	{ "link",			0, 'l' },
74 	{ "list",			0, 't' },
75 	{ "lrzip",			0, OPTION_LRZIP },
76 	{ "lzma",			0, OPTION_LZMA },
77 	{ "lzop",			0, OPTION_LZOP },
78 	{ "make-directories",		0, 'd' },
79 	{ "no-preserve-owner",		0, OPTION_NO_PRESERVE_OWNER },
80 	{ "null",			0, '0' },
81 	{ "numeric-uid-gid",		0, 'n' },
82 	{ "owner",			1, 'R' },
83 	{ "pass-through",		0, 'p' },
84 	{ "preserve-modification-time", 0, 'm' },
85 	{ "preserve-owner",		0, OPTION_PRESERVE_OWNER },
86 	{ "quiet",			0, OPTION_QUIET },
87 	{ "unconditional",		0, 'u' },
88 	{ "uuencode",			0, OPTION_UUENCODE },
89 	{ "verbose",			0, 'v' },
90 	{ "version",			0, OPTION_VERSION },
91 	{ "xz",				0, 'J' },
92 	{ NULL, 0, 0 }
93 };
94 
95 /*
96  * I used to try to select platform-provided getopt() or
97  * getopt_long(), but that caused a lot of headaches.  In particular,
98  * I couldn't consistently use long options in the test harness
99  * because not all platforms have getopt_long().  That in turn led to
100  * overuse of the -W hack in the test harness, which made it rough to
101  * run the test harness against GNU cpio.  (I periodically run the
102  * test harness here against GNU cpio as a sanity-check.  Yes,
103  * I've found a couple of bugs in GNU cpio that way.)
104  */
105 int
106 cpio_getopt(struct cpio *cpio)
107 {
108 	enum { state_start = 0, state_next_word, state_short, state_long };
109 	static int state = state_start;
110 	static char *opt_word;
111 
112 	const struct option *popt, *match = NULL, *match2 = NULL;
113 	const char *p, *long_prefix = "--";
114 	size_t optlength;
115 	int opt = '?';
116 	int required = 0;
117 
118 	cpio->argument = NULL;
119 
120 	/* First time through, initialize everything. */
121 	if (state == state_start) {
122 		/* Skip program name. */
123 		++cpio->argv;
124 		--cpio->argc;
125 		state = state_next_word;
126 	}
127 
128 	/*
129 	 * We're ready to look at the next word in argv.
130 	 */
131 	if (state == state_next_word) {
132 		/* No more arguments, so no more options. */
133 		if (cpio->argv[0] == NULL)
134 			return (-1);
135 		/* Doesn't start with '-', so no more options. */
136 		if (cpio->argv[0][0] != '-')
137 			return (-1);
138 		/* "--" marks end of options; consume it and return. */
139 		if (strcmp(cpio->argv[0], "--") == 0) {
140 			++cpio->argv;
141 			--cpio->argc;
142 			return (-1);
143 		}
144 		/* Get next word for parsing. */
145 		opt_word = *cpio->argv++;
146 		--cpio->argc;
147 		if (opt_word[1] == '-') {
148 			/* Set up long option parser. */
149 			state = state_long;
150 			opt_word += 2; /* Skip leading '--' */
151 		} else {
152 			/* Set up short option parser. */
153 			state = state_short;
154 			++opt_word;  /* Skip leading '-' */
155 		}
156 	}
157 
158 	/*
159 	 * We're parsing a group of POSIX-style single-character options.
160 	 */
161 	if (state == state_short) {
162 		/* Peel next option off of a group of short options. */
163 		opt = *opt_word++;
164 		if (opt == '\0') {
165 			/* End of this group; recurse to get next option. */
166 			state = state_next_word;
167 			return cpio_getopt(cpio);
168 		}
169 
170 		/* Does this option take an argument? */
171 		p = strchr(short_options, opt);
172 		if (p == NULL)
173 			return ('?');
174 		if (p[1] == ':')
175 			required = 1;
176 
177 		/* If it takes an argument, parse that. */
178 		if (required) {
179 			/* If arg is run-in, opt_word already points to it. */
180 			if (opt_word[0] == '\0') {
181 				/* Otherwise, pick up the next word. */
182 				opt_word = *cpio->argv;
183 				if (opt_word == NULL) {
184 					lafe_warnc(0,
185 					    "Option -%c requires an argument",
186 					    opt);
187 					return ('?');
188 				}
189 				++cpio->argv;
190 				--cpio->argc;
191 			}
192 			if (opt == 'W') {
193 				state = state_long;
194 				long_prefix = "-W "; /* For clearer errors. */
195 			} else {
196 				state = state_next_word;
197 				cpio->argument = opt_word;
198 			}
199 		}
200 	}
201 
202 	/* We're reading a long option, including -W long=arg convention. */
203 	if (state == state_long) {
204 		/* After this long option, we'll be starting a new word. */
205 		state = state_next_word;
206 
207 		/* Option name ends at '=' if there is one. */
208 		p = strchr(opt_word, '=');
209 		if (p != NULL) {
210 			optlength = (size_t)(p - opt_word);
211 			cpio->argument = (char *)(uintptr_t)(p + 1);
212 		} else {
213 			optlength = strlen(opt_word);
214 		}
215 
216 		/* Search the table for an unambiguous match. */
217 		for (popt = cpio_longopts; popt->name != NULL; popt++) {
218 			/* Short-circuit if first chars don't match. */
219 			if (popt->name[0] != opt_word[0])
220 				continue;
221 			/* If option is a prefix of name in table, record it.*/
222 			if (strncmp(opt_word, popt->name, optlength) == 0) {
223 				match2 = match; /* Record up to two matches. */
224 				match = popt;
225 				/* If it's an exact match, we're done. */
226 				if (strlen(popt->name) == optlength) {
227 					match2 = NULL; /* Forget the others. */
228 					break;
229 				}
230 			}
231 		}
232 
233 		/* Fail if there wasn't a unique match. */
234 		if (match == NULL) {
235 			lafe_warnc(0,
236 			    "Option %s%s is not supported",
237 			    long_prefix, opt_word);
238 			return ('?');
239 		}
240 		if (match2 != NULL) {
241 			lafe_warnc(0,
242 			    "Ambiguous option %s%s (matches --%s and --%s)",
243 			    long_prefix, opt_word, match->name, match2->name);
244 			return ('?');
245 		}
246 
247 		/* We've found a unique match; does it need an argument? */
248 		if (match->required) {
249 			/* Argument required: get next word if necessary. */
250 			if (cpio->argument == NULL) {
251 				cpio->argument = *cpio->argv;
252 				if (cpio->argument == NULL) {
253 					lafe_warnc(0,
254 					    "Option %s%s requires an argument",
255 					    long_prefix, match->name);
256 					return ('?');
257 				}
258 				++cpio->argv;
259 				--cpio->argc;
260 			}
261 		} else {
262 			/* Argument forbidden: fail if there is one. */
263 			if (cpio->argument != NULL) {
264 				lafe_warnc(0,
265 				    "Option %s%s does not allow an argument",
266 				    long_prefix, match->name);
267 				return ('?');
268 			}
269 		}
270 		return (match->equivalent);
271 	}
272 
273 	return (opt);
274 }
275 
276 
277 /*
278  * Parse the argument to the -R or --owner flag.
279  *
280  * The format is one of the following:
281  *   <username|uid>    - Override user but not group
282  *   <username>:   - Override both, group is user's default group
283  *   <uid>:    - Override user but not group
284  *   <username|uid>:<groupname|gid> - Override both
285  *   :<groupname|gid>  - Override group but not user
286  *
287  * Where uid/gid are decimal representations and groupname/username
288  * are names to be looked up in system database.  Note that we try
289  * to look up an argument as a name first, then try numeric parsing.
290  *
291  * A period can be used instead of the colon.
292  *
293  * Sets uid/gid return as appropriate, -1 indicates uid/gid not specified.
294  * TODO: If the spec uses uname/gname, then return those to the caller
295  * as well.  If the spec provides uid/gid, just return names as NULL.
296  *
297  * Returns NULL if no error, otherwise returns error string for display.
298  *
299  */
300 const char *
301 owner_parse(const char *spec, int *uid, int *gid)
302 {
303 	static char errbuff[128];
304 	const char *u, *ue, *g;
305 
306 	*uid = -1;
307 	*gid = -1;
308 
309 	if (spec[0] == '\0')
310 		return ("Invalid empty user/group spec");
311 
312 	/*
313 	 * Split spec into [user][:.][group]
314 	 *  u -> first char of username, NULL if no username
315 	 *  ue -> first char after username (colon, period, or \0)
316 	 *  g -> first char of group name
317 	 */
318 	if (*spec == ':' || *spec == '.') {
319 		/* If spec starts with ':' or '.', then just group. */
320 		ue = u = NULL;
321 		g = spec + 1;
322 	} else {
323 		/* Otherwise, [user] or [user][:] or [user][:][group] */
324 		ue = u = spec;
325 		while (*ue != ':' && *ue != '.' && *ue != '\0')
326 			++ue;
327 		g = ue;
328 		if (*g != '\0') /* Skip : or . to find first char of group. */
329 			++g;
330 	}
331 
332 	if (u != NULL) {
333 		/* Look up user: ue is first char after end of user. */
334 		char *user;
335 		struct passwd *pwent;
336 
337 		user = (char *)malloc(ue - u + 1);
338 		if (user == NULL)
339 			return ("Couldn't allocate memory");
340 		memcpy(user, u, ue - u);
341 		user[ue - u] = '\0';
342 		if ((pwent = getpwnam(user)) != NULL) {
343 			*uid = pwent->pw_uid;
344 			if (*ue != '\0')
345 				*gid = pwent->pw_gid;
346 		} else {
347 			char *end;
348 			errno = 0;
349 			*uid = (int)strtoul(user, &end, 10);
350 			if (errno || *end != '\0') {
351 				snprintf(errbuff, sizeof(errbuff),
352 				    "Couldn't lookup user ``%s''", user);
353 				errbuff[sizeof(errbuff) - 1] = '\0';
354 				free(user);
355 				return (errbuff);
356 			}
357 		}
358 		free(user);
359 	}
360 
361 	if (*g != '\0') {
362 		struct group *grp;
363 		if ((grp = getgrnam(g)) != NULL) {
364 			*gid = grp->gr_gid;
365 		} else {
366 			char *end;
367 			errno = 0;
368 			*gid = (int)strtoul(g, &end, 10);
369 			if (errno || *end != '\0') {
370 				snprintf(errbuff, sizeof(errbuff),
371 				    "Couldn't lookup group ``%s''", g);
372 				errbuff[sizeof(errbuff) - 1] = '\0';
373 				return (errbuff);
374 			}
375 		}
376 	}
377 	return (NULL);
378 }
379