xref: /original-bsd/bin/cp/utils.c (revision e58c8952)
1 /*-
2  * Copyright (c) 1991, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 static char sccsid[] = "@(#)utils.c	8.3 (Berkeley) 04/01/94";
10 #endif /* not lint */
11 
12 #include <sys/param.h>
13 #include <sys/stat.h>
14 #include <sys/mman.h>
15 #include <sys/time.h>
16 
17 #include <err.h>
18 #include <errno.h>
19 #include <fcntl.h>
20 #include <fts.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <unistd.h>
25 
26 #include "extern.h"
27 
28 int
29 copy_file(entp, dne)
30 	FTSENT *entp;
31 	int dne;
32 {
33 	static char buf[MAXBSIZE];
34 	struct stat to_stat, *fs;
35 	int ch, checkch, from_fd, rcount, rval, to_fd, wcount;
36 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
37 	char *p;
38 #endif
39 
40 	if ((from_fd = open(entp->fts_path, O_RDONLY, 0)) == -1) {
41 		warn("%s", entp->fts_path);
42 		return (1);
43 	}
44 
45 	fs = entp->fts_statp;
46 
47 	/*
48 	 * If the file exists and we're interactive, verify with the user.
49 	 * If the file DNE, set the mode to be the from file, minus setuid
50 	 * bits, modified by the umask; arguably wrong, but it makes copying
51 	 * executables work right and it's been that way forever.  (The
52 	 * other choice is 666 or'ed with the execute bits on the from file
53 	 * modified by the umask.)
54 	 */
55 	if (!dne) {
56 		if (iflag) {
57 			(void)fprintf(stderr, "overwrite %s? ", to.p_path);
58 			checkch = ch = getchar();
59 			while (ch != '\n' && ch != EOF)
60 				ch = getchar();
61 			if (checkch != 'y') {
62 				(void)close(from_fd);
63 				return (0);
64 			}
65 		}
66 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0);
67 	} else
68 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
69 		    fs->st_mode & ~(S_ISUID | S_ISGID));
70 
71 	if (to_fd == -1) {
72 		warn("%s", to.p_path);
73 		(void)close(from_fd);
74 		return (1);;
75 	}
76 
77 	rval = 0;
78 
79 	/*
80 	 * Mmap and write if less than 8M (the limit is so we don't totally
81 	 * trash memory on big files.  This is really a minor hack, but it
82 	 * wins some CPU back.
83 	 */
84 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
85 	if (fs->st_size <= 8 * 1048576) {
86 		if ((p = mmap(NULL, (size_t)fs->st_size, PROT_READ,
87 		    0, from_fd, (off_t)0)) == (char *)-1) {
88 			warn("%s", entp->fts_path);
89 			rval = 1;
90 		} else {
91 			if (write(to_fd, p, fs->st_size) != fs->st_size) {
92 				warn("%s", to.p_path);
93 				rval = 1;
94 			}
95 			/* Some systems don't unmap on close(2). */
96 			if (munmap(p, fs->st_size) < 0) {
97 				warn("%s", entp->fts_path);
98 				rval = 1;
99 			}
100 		}
101 	} else
102 #endif
103 	{
104 		while ((rcount = read(from_fd, buf, MAXBSIZE)) > 0) {
105 			wcount = write(to_fd, buf, rcount);
106 			if (rcount != wcount || wcount == -1) {
107 				warn("%s", to.p_path);
108 				rval = 1;
109 				break;
110 			}
111 		}
112 		if (rcount < 0) {
113 			warn("%s", entp->fts_path);
114 			rval = 1;
115 		}
116 	}
117 
118 	/* If the copy went bad, lose the file. */
119 	if (rval == 1) {
120 		(void)unlink(to.p_path);
121 		(void)close(from_fd);
122 		(void)close(to_fd);
123 		return (1);
124 	}
125 
126 	if (pflag && setfile(fs, to_fd))
127 		rval = 1;
128 	/*
129 	 * If the source was setuid or setgid, lose the bits unless the
130 	 * copy is owned by the same user and group.
131 	 */
132 #define	RETAINBITS \
133 	(S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO)
134 	else if (fs->st_mode & (S_ISUID | S_ISGID) && fs->st_uid == myuid)
135 		if (fstat(to_fd, &to_stat)) {
136 			warn("%s", to.p_path);
137 			rval = 1;
138 		} else if (fs->st_gid == to_stat.st_gid &&
139 		    fchmod(to_fd, fs->st_mode & RETAINBITS & ~myumask)) {
140 			warn("%s", to.p_path);
141 			rval = 1;
142 		}
143 	(void)close(from_fd);
144 	if (close(to_fd)) {
145 		warn("%s", to.p_path);
146 		rval = 1;
147 	}
148 	return (rval);
149 }
150 
151 int
152 copy_link(p, exists)
153 	FTSENT *p;
154 	int exists;
155 {
156 	int len;
157 	char link[MAXPATHLEN];
158 
159 	if ((len = readlink(p->fts_path, link, sizeof(link))) == -1) {
160 		warn("readlink: %s", p->fts_path);
161 		return (1);
162 	}
163 	link[len] = '\0';
164 	if (exists && unlink(to.p_path)) {
165 		warn("unlink: %s", to.p_path);
166 		return (1);
167 	}
168 	if (symlink(link, to.p_path)) {
169 		warn("symlink: %s", link);
170 		return (1);
171 	}
172 	return (0);
173 }
174 
175 int
176 copy_fifo(from_stat, exists)
177 	struct stat *from_stat;
178 	int exists;
179 {
180 	if (exists && unlink(to.p_path)) {
181 		warn("unlink: %s", to.p_path);
182 		return (1);
183 	}
184 	if (mkfifo(to.p_path, from_stat->st_mode)) {
185 		warn("mkfifo: %s", to.p_path);
186 		return (1);
187 	}
188 	return (pflag ? setfile(from_stat, 0) : 0);
189 }
190 
191 int
192 copy_special(from_stat, exists)
193 	struct stat *from_stat;
194 	int exists;
195 {
196 	if (exists && unlink(to.p_path)) {
197 		warn("unlink: %s", to.p_path);
198 		return (1);
199 	}
200 	if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) {
201 		warn("mknod: %s", to.p_path);
202 		return (1);
203 	}
204 	return (pflag ? setfile(from_stat, 0) : 0);
205 }
206 
207 
208 int
209 setfile(fs, fd)
210 	register struct stat *fs;
211 	int fd;
212 {
213 	static struct timeval tv[2];
214 	int rval;
215 
216 	rval = 0;
217 	fs->st_mode &= S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO;
218 
219 	TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
220 	TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
221 	if (utimes(to.p_path, tv)) {
222 		warn("utimes: %s", to.p_path);
223 		rval = 1;
224 	}
225 	/*
226 	 * Changing the ownership probably won't succeed, unless we're root
227 	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
228 	 * the mode; current BSD behavior is to remove all setuid bits on
229 	 * chown.  If chown fails, lose setuid/setgid bits.
230 	 */
231 	if (fd ? fchown(fd, fs->st_uid, fs->st_gid) :
232 	    chown(to.p_path, fs->st_uid, fs->st_gid)) {
233 		if (errno != EPERM) {
234 			warn("chown: %s", to.p_path);
235 			rval = 1;
236 		}
237 		fs->st_mode &= ~(S_ISUID | S_ISGID);
238 	}
239 	if (fd ? fchmod(fd, fs->st_mode) : chmod(to.p_path, fs->st_mode)) {
240 		warn("chown: %s", to.p_path);
241 		rval = 1;
242 	}
243 
244 	if (fd ?
245 	    fchflags(fd, fs->st_flags) : chflags(to.p_path, fs->st_flags)) {
246 		warn("chflags: %s", to.p_path);
247 		rval = 1;
248 	}
249 	return (rval);
250 }
251 
252 void
253 usage()
254 {
255 	(void)fprintf(stderr, "%s\n%s\n",
256 "usage: cp [-R [-H | -L | -P] [-fip] src target",
257 "       cp [-R [-H | -L | -P] [-fip] src1 ... srcN directory");
258 	exit(1);
259 }
260