xref: /openbsd-src/bin/cp/utils.c (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*	$OpenBSD: utils.c,v 1.16 2001/06/25 04:35:31 art Exp $	*/
2 /*	$NetBSD: utils.c,v 1.6 1997/02/26 14:40:51 cgd Exp $	*/
3 
4 /*-
5  * Copyright (c) 1991, 1993, 1994
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgment:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)utils.c	8.3 (Berkeley) 4/1/94";
40 #else
41 static char rcsid[] = "$OpenBSD: utils.c,v 1.16 2001/06/25 04:35:31 art Exp $";
42 #endif
43 #endif /* not lint */
44 
45 #include <sys/param.h>
46 #include <sys/stat.h>
47 #include <sys/mman.h>
48 #include <sys/time.h>
49 
50 #include <err.h>
51 #include <errno.h>
52 #include <fcntl.h>
53 #include <fts.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <unistd.h>
58 
59 #include "extern.h"
60 
61 int
62 copy_file(entp, dne)
63 	FTSENT *entp;
64 	int dne;
65 {
66 	static char buf[MAXBSIZE];
67 	struct stat to_stat, *fs;
68 	int ch, checkch, from_fd, rcount, rval, to_fd, wcount;
69 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
70 	char *p;
71 #endif
72 
73 	if ((from_fd = open(entp->fts_path, O_RDONLY, 0)) == -1) {
74 		warn("%s", entp->fts_path);
75 		return (1);
76 	}
77 
78 	fs = entp->fts_statp;
79 
80 	/*
81 	 * In -f (force) mode, we always unlink the destination first
82 	 * if it exists.  Note that -i and -f are mututally exclusive.
83 	 */
84 	if (!dne && fflag)
85 		(void)unlink(to.p_path);
86 
87 	/*
88 	 * If the file exists and we're interactive, verify with the user.
89 	 * If the file DNE, set the mode to be the from file, minus setuid
90 	 * bits, modified by the umask; arguably wrong, but it makes copying
91 	 * executables work right and it's been that way forever.  (The
92 	 * other choice is 666 or'ed with the execute bits on the from file
93 	 * modified by the umask.)
94 	 */
95 	if (!dne && !fflag) {
96 		if (iflag) {
97 			(void)fprintf(stderr, "overwrite %s? ", to.p_path);
98 			checkch = ch = getchar();
99 			while (ch != '\n' && ch != EOF)
100 				ch = getchar();
101 			if (checkch != 'y' && checkch != 'Y') {
102 				(void)close(from_fd);
103 				return (0);
104 			}
105 		}
106 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0);
107 	} else
108 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
109 		    fs->st_mode & ~(S_ISTXT | S_ISUID | S_ISGID));
110 
111 	if (to_fd == -1) {
112 		warn("%s", to.p_path);
113 		(void)close(from_fd);
114 		return (1);;
115 	}
116 
117 	rval = 0;
118 
119 	/*
120 	 * Mmap and write if less than 8M (the limit is so we don't totally
121 	 * trash memory on big files.  This is really a minor hack, but it
122 	 * wins some CPU back.
123 	 */
124 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
125 	if (fs->st_size <= 8 * 1048576) {
126 		if ((p = mmap(NULL, (size_t)fs->st_size, PROT_READ,
127 		    MAP_FILE|MAP_SHARED, from_fd, (off_t)0)) == MAP_FAILED) {
128 			warn("mmap: %s", entp->fts_path);
129 			rval = 1;
130 		} else {
131 			if (write(to_fd, p, fs->st_size) != fs->st_size) {
132 				warn("%s", to.p_path);
133 				rval = 1;
134 			}
135 			/* Some systems don't unmap on close(2). */
136 			if (munmap(p, fs->st_size) < 0) {
137 				warn("%s", entp->fts_path);
138 				rval = 1;
139 			}
140 		}
141 	} else
142 #endif
143 	{
144 		while ((rcount = read(from_fd, buf, MAXBSIZE)) > 0) {
145 			wcount = write(to_fd, buf, rcount);
146 			if (rcount != wcount || wcount == -1) {
147 				warn("%s", to.p_path);
148 				rval = 1;
149 				break;
150 			}
151 		}
152 		if (rcount < 0) {
153 			warn("%s", entp->fts_path);
154 			rval = 1;
155 		}
156 	}
157 
158 	if (rval == 1) {
159 		(void)close(from_fd);
160 		(void)close(to_fd);
161 		return (1);
162 	}
163 
164 	if (pflag && setfile(fs, to_fd))
165 		rval = 1;
166 	/*
167 	 * If the source was setuid or setgid, lose the bits unless the
168 	 * copy is owned by the same user and group.
169 	 */
170 #define	RETAINBITS \
171 	(S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO)
172 	else if (fs->st_mode & (S_ISUID | S_ISGID) && fs->st_uid == myuid) {
173 		if (fstat(to_fd, &to_stat)) {
174 			warn("%s", to.p_path);
175 			rval = 1;
176 		} else if (fs->st_gid == to_stat.st_gid &&
177 		    fchmod(to_fd, fs->st_mode & RETAINBITS & ~myumask)) {
178 			warn("%s", to.p_path);
179 			rval = 1;
180 		}
181 	}
182 	(void)close(from_fd);
183 	if (close(to_fd)) {
184 		warn("%s", to.p_path);
185 		rval = 1;
186 	}
187 	return (rval);
188 }
189 
190 int
191 copy_link(p, exists)
192 	FTSENT *p;
193 	int exists;
194 {
195 	int len;
196 	char link[MAXPATHLEN];
197 
198 	if ((len = readlink(p->fts_path, link, sizeof(link)-1)) == -1) {
199 		warn("readlink: %s", p->fts_path);
200 		return (1);
201 	}
202 	link[len] = '\0';
203 	if (exists && unlink(to.p_path)) {
204 		warn("unlink: %s", to.p_path);
205 		return (1);
206 	}
207 	if (symlink(link, to.p_path)) {
208 		warn("symlink: %s", link);
209 		return (1);
210 	}
211 	return (pflag ? setlink(p->fts_statp) : 0);
212 }
213 
214 int
215 copy_fifo(from_stat, exists)
216 	struct stat *from_stat;
217 	int exists;
218 {
219 	if (exists && unlink(to.p_path)) {
220 		warn("unlink: %s", to.p_path);
221 		return (1);
222 	}
223 	if (mkfifo(to.p_path, from_stat->st_mode)) {
224 		warn("mkfifo: %s", to.p_path);
225 		return (1);
226 	}
227 	return (pflag ? setfile(from_stat, 0) : 0);
228 }
229 
230 int
231 copy_special(from_stat, exists)
232 	struct stat *from_stat;
233 	int exists;
234 {
235 	if (exists && unlink(to.p_path)) {
236 		warn("unlink: %s", to.p_path);
237 		return (1);
238 	}
239 	if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) {
240 		warn("mknod: %s", to.p_path);
241 		return (1);
242 	}
243 	return (pflag ? setfile(from_stat, 0) : 0);
244 }
245 
246 
247 int
248 setfile(fs, fd)
249 	struct stat *fs;
250 	int fd;
251 {
252 	static struct timeval tv[2];
253 	int rval;
254 
255 	rval = 0;
256 	fs->st_mode &= S_ISTXT | S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO;
257 
258 	TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
259 	TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
260 	if (utimes(to.p_path, tv)) {
261 		warn("utimes: %s", to.p_path);
262 		rval = 1;
263 	}
264 	/*
265 	 * Changing the ownership probably won't succeed, unless we're root
266 	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
267 	 * the mode; current BSD behavior is to remove all setuid bits on
268 	 * chown.  If chown fails, lose setuid/setgid bits.
269 	 */
270 	if (fd ? fchown(fd, fs->st_uid, fs->st_gid) :
271 	    chown(to.p_path, fs->st_uid, fs->st_gid)) {
272 		if (errno != EPERM) {
273 			warn("chown: %s", to.p_path);
274 			rval = 1;
275 		}
276 		fs->st_mode &= ~(S_ISTXT | S_ISUID | S_ISGID);
277 	}
278 	if (fd ? fchmod(fd, fs->st_mode) : chmod(to.p_path, fs->st_mode)) {
279 		warn("chown: %s", to.p_path);
280 		rval = 1;
281 	}
282 
283 	/*
284 	 * XXX
285 	 * NFS doesn't support chflags; ignore errors unless there's reason
286 	 * to believe we're losing bits.  (Note, this still won't be right
287 	 * if the server supports flags and we were trying to *remove* flags
288 	 * on a file that we copied, i.e., that we didn't create.)
289 	 */
290 	errno = 0;
291 	if (fd ? fchflags(fd, fs->st_flags) : chflags(to.p_path, fs->st_flags))
292 		if (errno != EOPNOTSUPP || fs->st_flags != 0) {
293 			warn("chflags: %s", to.p_path);
294 			rval = 1;
295 		}
296 	return (rval);
297 }
298 
299 
300 int
301 setlink(fs)
302 	register struct stat *fs;
303 {
304 
305 	if (lchown(to.p_path, fs->st_uid, fs->st_gid)) {
306 		if (errno != EPERM) {
307 			warn("lchown: %s", to.p_path);
308 			return (1);
309 		}
310 	}
311 	return (0);
312 }
313 
314 
315 void
316 usage()
317 {
318 	(void)fprintf(stderr, "%s\n%s\n",
319 	    "usage: cp [-R [-H | -L | -P]] [-fip] src target",
320 	    "       cp [-R [-H | -L | -P]] [-fip] src1 ... srcN directory");
321 	exit(1);
322 }
323