xref: /netbsd-src/bin/cp/utils.c (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
1 /*-
2  * Copyright (c) 1991, 1993, 1994
3  *	The Regents of the University of California.  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  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 /*static char sccsid[] = "from: @(#)utils.c	8.3 (Berkeley) 4/1/94";*/
36 static char *rcsid = "$Id: utils.c,v 1.2 1994/09/22 09:24:43 mycroft Exp $";
37 #endif /* not lint */
38 
39 #include <sys/param.h>
40 #include <sys/stat.h>
41 #include <sys/mman.h>
42 #include <sys/time.h>
43 
44 #include <err.h>
45 #include <errno.h>
46 #include <fcntl.h>
47 #include <fts.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52 
53 #include "extern.h"
54 
55 int
56 copy_file(entp, dne)
57 	FTSENT *entp;
58 	int dne;
59 {
60 	static char buf[MAXBSIZE];
61 	struct stat to_stat, *fs;
62 	int ch, checkch, from_fd, rcount, rval, to_fd, wcount;
63 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
64 	char *p;
65 #endif
66 
67 	if ((from_fd = open(entp->fts_path, O_RDONLY, 0)) == -1) {
68 		warn("%s", entp->fts_path);
69 		return (1);
70 	}
71 
72 	fs = entp->fts_statp;
73 
74 	/*
75 	 * If the file exists and we're interactive, verify with the user.
76 	 * If the file DNE, set the mode to be the from file, minus setuid
77 	 * bits, modified by the umask; arguably wrong, but it makes copying
78 	 * executables work right and it's been that way forever.  (The
79 	 * other choice is 666 or'ed with the execute bits on the from file
80 	 * modified by the umask.)
81 	 */
82 	if (!dne) {
83 		if (iflag) {
84 			(void)fprintf(stderr, "overwrite %s? ", to.p_path);
85 			checkch = ch = getchar();
86 			while (ch != '\n' && ch != EOF)
87 				ch = getchar();
88 			if (checkch != 'y' && checkch != 'Y') {
89 				(void)close(from_fd);
90 				return (0);
91 			}
92 		}
93 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0);
94 	} else
95 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
96 		    fs->st_mode & ~(S_ISUID | S_ISGID));
97 
98 	if (to_fd == -1) {
99 		warn("%s", to.p_path);
100 		(void)close(from_fd);
101 		return (1);;
102 	}
103 
104 	rval = 0;
105 
106 	/*
107 	 * Mmap and write if less than 8M (the limit is so we don't totally
108 	 * trash memory on big files.  This is really a minor hack, but it
109 	 * wins some CPU back.
110 	 */
111 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
112 	if (fs->st_size <= 8 * 1048576) {
113 		if ((p = mmap(NULL, (size_t)fs->st_size, PROT_READ,
114 		    0, from_fd, (off_t)0)) == (char *)-1) {
115 			warn("%s", entp->fts_path);
116 			rval = 1;
117 		} else {
118 			if (write(to_fd, p, fs->st_size) != fs->st_size) {
119 				warn("%s", to.p_path);
120 				rval = 1;
121 			}
122 			/* Some systems don't unmap on close(2). */
123 			if (munmap(p, fs->st_size) < 0) {
124 				warn("%s", entp->fts_path);
125 				rval = 1;
126 			}
127 		}
128 	} else
129 #endif
130 	{
131 		while ((rcount = read(from_fd, buf, MAXBSIZE)) > 0) {
132 			wcount = write(to_fd, buf, rcount);
133 			if (rcount != wcount || wcount == -1) {
134 				warn("%s", to.p_path);
135 				rval = 1;
136 				break;
137 			}
138 		}
139 		if (rcount < 0) {
140 			warn("%s", entp->fts_path);
141 			rval = 1;
142 		}
143 	}
144 
145 	/* If the copy went bad, lose the file. */
146 	if (rval == 1) {
147 		(void)unlink(to.p_path);
148 		(void)close(from_fd);
149 		(void)close(to_fd);
150 		return (1);
151 	}
152 
153 	if (pflag && setfile(fs, to_fd))
154 		rval = 1;
155 	/*
156 	 * If the source was setuid or setgid, lose the bits unless the
157 	 * copy is owned by the same user and group.
158 	 */
159 #define	RETAINBITS \
160 	(S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO)
161 	else if (fs->st_mode & (S_ISUID | S_ISGID) && fs->st_uid == myuid)
162 		if (fstat(to_fd, &to_stat)) {
163 			warn("%s", to.p_path);
164 			rval = 1;
165 		} else if (fs->st_gid == to_stat.st_gid &&
166 		    fchmod(to_fd, fs->st_mode & RETAINBITS & ~myumask)) {
167 			warn("%s", to.p_path);
168 			rval = 1;
169 		}
170 	(void)close(from_fd);
171 	if (close(to_fd)) {
172 		warn("%s", to.p_path);
173 		rval = 1;
174 	}
175 	return (rval);
176 }
177 
178 int
179 copy_link(p, exists)
180 	FTSENT *p;
181 	int exists;
182 {
183 	int len;
184 	char link[MAXPATHLEN];
185 
186 	if ((len = readlink(p->fts_path, link, sizeof(link))) == -1) {
187 		warn("readlink: %s", p->fts_path);
188 		return (1);
189 	}
190 	link[len] = '\0';
191 	if (exists && unlink(to.p_path)) {
192 		warn("unlink: %s", to.p_path);
193 		return (1);
194 	}
195 	if (symlink(link, to.p_path)) {
196 		warn("symlink: %s", link);
197 		return (1);
198 	}
199 	return (0);
200 }
201 
202 int
203 copy_fifo(from_stat, exists)
204 	struct stat *from_stat;
205 	int exists;
206 {
207 	if (exists && unlink(to.p_path)) {
208 		warn("unlink: %s", to.p_path);
209 		return (1);
210 	}
211 	if (mkfifo(to.p_path, from_stat->st_mode)) {
212 		warn("mkfifo: %s", to.p_path);
213 		return (1);
214 	}
215 	return (pflag ? setfile(from_stat, 0) : 0);
216 }
217 
218 int
219 copy_special(from_stat, exists)
220 	struct stat *from_stat;
221 	int exists;
222 {
223 	if (exists && unlink(to.p_path)) {
224 		warn("unlink: %s", to.p_path);
225 		return (1);
226 	}
227 	if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) {
228 		warn("mknod: %s", to.p_path);
229 		return (1);
230 	}
231 	return (pflag ? setfile(from_stat, 0) : 0);
232 }
233 
234 
235 int
236 setfile(fs, fd)
237 	register struct stat *fs;
238 	int fd;
239 {
240 	static struct timeval tv[2];
241 	int rval;
242 
243 	rval = 0;
244 	fs->st_mode &= S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO;
245 
246 	TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
247 	TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
248 	if (utimes(to.p_path, tv)) {
249 		warn("utimes: %s", to.p_path);
250 		rval = 1;
251 	}
252 	/*
253 	 * Changing the ownership probably won't succeed, unless we're root
254 	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
255 	 * the mode; current BSD behavior is to remove all setuid bits on
256 	 * chown.  If chown fails, lose setuid/setgid bits.
257 	 */
258 	if (fd ? fchown(fd, fs->st_uid, fs->st_gid) :
259 	    chown(to.p_path, fs->st_uid, fs->st_gid)) {
260 		if (errno != EPERM) {
261 			warn("chown: %s", to.p_path);
262 			rval = 1;
263 		}
264 		fs->st_mode &= ~(S_ISUID | S_ISGID);
265 	}
266 	if (fd ? fchmod(fd, fs->st_mode) : chmod(to.p_path, fs->st_mode)) {
267 		warn("chown: %s", to.p_path);
268 		rval = 1;
269 	}
270 
271 	if (fd ?
272 	    fchflags(fd, fs->st_flags) : chflags(to.p_path, fs->st_flags)) {
273 		warn("chflags: %s", to.p_path);
274 		rval = 1;
275 	}
276 	return (rval);
277 }
278 
279 void
280 usage()
281 {
282 	(void)fprintf(stderr, "%s\n%s\n",
283 "usage: cp [-R [-H | -L | -P] [-fip] src target",
284 "       cp [-R [-H | -L | -P] [-fip] src1 ... srcN directory");
285 	exit(1);
286 }
287