1 /* $OpenBSD: utils.c,v 1.48 2019/06/28 13:34:58 deraadt 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. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/param.h> /* MAXBSIZE */ 34 #include <sys/stat.h> 35 #include <sys/mman.h> 36 #include <sys/time.h> 37 38 #include <err.h> 39 #include <errno.h> 40 #include <fcntl.h> 41 #include <fts.h> 42 #include <stdio.h> 43 #include <stdlib.h> 44 #include <string.h> 45 #include <unistd.h> 46 #include <limits.h> 47 48 #include "extern.h" 49 50 int copy_overwrite(void); 51 52 int 53 copy_file(FTSENT *entp, int exists) 54 { 55 static char *buf; 56 static char *zeroes; 57 struct stat to_stat, *fs; 58 int from_fd, rcount, rval, to_fd, wcount; 59 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED 60 char *p; 61 #endif 62 63 if (!buf) { 64 buf = malloc(MAXBSIZE); 65 if (!buf) 66 err(1, "malloc"); 67 } 68 if (!zeroes) { 69 zeroes = calloc(1, MAXBSIZE); 70 if (!zeroes) 71 err(1, "calloc"); 72 } 73 74 if ((from_fd = open(entp->fts_path, O_RDONLY, 0)) == -1) { 75 warn("%s", entp->fts_path); 76 return (1); 77 } 78 79 fs = entp->fts_statp; 80 81 /* 82 * In -f (force) mode, we always unlink the destination first 83 * if it exists. Note that -i and -f are mutually exclusive. 84 */ 85 if (exists && fflag) 86 (void)unlink(to.p_path); 87 88 /* 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 (exists && !fflag) { 96 if (!copy_overwrite()) { 97 (void)close(from_fd); 98 return 2; 99 } 100 to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0); 101 } else 102 to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT, 103 fs->st_mode & ~(S_ISTXT | S_ISUID | S_ISGID)); 104 105 if (to_fd == -1) { 106 warn("%s", to.p_path); 107 (void)close(from_fd); 108 return (1); 109 } 110 111 rval = 0; 112 113 /* 114 * Mmap and write if less than 8M (the limit is so we don't totally 115 * trash memory on big files. This is really a minor hack, but it 116 * wins some CPU back. 117 */ 118 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED 119 /* XXX broken for 0-size mmap */ 120 if (fs->st_size <= 8 * 1048576) { 121 if ((p = mmap(NULL, (size_t)fs->st_size, PROT_READ, 122 MAP_FILE|MAP_SHARED, from_fd, (off_t)0)) == MAP_FAILED) { 123 warn("mmap: %s", entp->fts_path); 124 rval = 1; 125 } else { 126 madvise(p, fs->st_size, MADV_SEQUENTIAL); 127 if (write(to_fd, p, fs->st_size) != fs->st_size) { 128 warn("%s", to.p_path); 129 rval = 1; 130 } 131 /* Some systems don't unmap on close(2). */ 132 if (munmap(p, fs->st_size) == -1) { 133 warn("%s", entp->fts_path); 134 rval = 1; 135 } 136 } 137 } else 138 #endif 139 { 140 int skipholes = 0; 141 struct stat tosb; 142 if (!fstat(to_fd, &tosb) && S_ISREG(tosb.st_mode)) 143 skipholes = 1; 144 while ((rcount = read(from_fd, buf, MAXBSIZE)) > 0) { 145 if (skipholes && memcmp(buf, zeroes, rcount) == 0) 146 wcount = lseek(to_fd, rcount, SEEK_CUR) == -1 ? -1 : rcount; 147 else 148 wcount = write(to_fd, buf, rcount); 149 if (rcount != wcount || wcount == -1) { 150 warn("%s", to.p_path); 151 rval = 1; 152 break; 153 } 154 } 155 if (skipholes && rcount != -1) 156 rcount = ftruncate(to_fd, lseek(to_fd, 0, SEEK_CUR)); 157 if (rcount == -1) { 158 warn("%s", entp->fts_path); 159 rval = 1; 160 } 161 } 162 163 if (rval == 1) { 164 (void)close(from_fd); 165 (void)close(to_fd); 166 return (1); 167 } 168 169 if (pflag && setfile(fs, to_fd)) 170 rval = 1; 171 /* 172 * If the source was setuid or setgid, lose the bits unless the 173 * copy is owned by the same user and group. 174 */ 175 #define RETAINBITS \ 176 (S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO) 177 if (!pflag && !exists && 178 fs->st_mode & (S_ISUID | S_ISGID) && fs->st_uid == myuid) { 179 if (fstat(to_fd, &to_stat)) { 180 warn("%s", to.p_path); 181 rval = 1; 182 } else if (fs->st_gid == to_stat.st_gid && 183 fchmod(to_fd, fs->st_mode & RETAINBITS & ~myumask)) { 184 warn("%s", to.p_path); 185 rval = 1; 186 } 187 } 188 (void)close(from_fd); 189 if (close(to_fd)) { 190 warn("%s", to.p_path); 191 rval = 1; 192 } 193 return (rval); 194 } 195 196 int 197 copy_link(FTSENT *p, int exists) 198 { 199 int len; 200 char name[PATH_MAX]; 201 202 if (exists && !copy_overwrite()) 203 return (2); 204 if ((len = readlink(p->fts_path, name, sizeof(name)-1)) == -1) { 205 warn("readlink: %s", p->fts_path); 206 return (1); 207 } 208 name[len] = '\0'; 209 if (exists && unlink(to.p_path)) { 210 warn("unlink: %s", to.p_path); 211 return (1); 212 } 213 if (symlink(name, to.p_path)) { 214 warn("symlink: %s", name); 215 return (1); 216 } 217 return (pflag ? setfile(p->fts_statp, -1) : 0); 218 } 219 220 int 221 copy_fifo(struct stat *from_stat, int exists) 222 { 223 if (exists && !copy_overwrite()) 224 return (2); 225 if (exists && unlink(to.p_path)) { 226 warn("unlink: %s", to.p_path); 227 return (1); 228 } 229 if (mkfifo(to.p_path, from_stat->st_mode)) { 230 warn("mkfifo: %s", to.p_path); 231 return (1); 232 } 233 return (pflag ? setfile(from_stat, -1) : 0); 234 } 235 236 int 237 copy_special(struct stat *from_stat, int exists) 238 { 239 if (exists && !copy_overwrite()) 240 return (2); 241 if (exists && unlink(to.p_path)) { 242 warn("unlink: %s", to.p_path); 243 return (1); 244 } 245 if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) { 246 warn("mknod: %s", to.p_path); 247 return (1); 248 } 249 return (pflag ? setfile(from_stat, -1) : 0); 250 } 251 252 /* 253 * If the file exists and we're interactive, verify with the user. 254 */ 255 int 256 copy_overwrite(void) 257 { 258 int ch, checkch; 259 260 if (iflag) { 261 (void)fprintf(stderr, "overwrite %s? ", to.p_path); 262 checkch = ch = getchar(); 263 while (ch != '\n' && ch != EOF) 264 ch = getchar(); 265 if (checkch != 'y' && checkch != 'Y') 266 return (0); 267 } 268 return 1; 269 } 270 271 int 272 setfile(struct stat *fs, int fd) 273 { 274 struct timespec ts[2]; 275 int rval; 276 277 rval = 0; 278 fs->st_mode &= S_ISTXT | S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO; 279 280 ts[0] = fs->st_atim; 281 ts[1] = fs->st_mtim; 282 if (fd >= 0 ? futimens(fd, ts) : 283 utimensat(AT_FDCWD, to.p_path, ts, AT_SYMLINK_NOFOLLOW)) { 284 warn("update times: %s", to.p_path); 285 rval = 1; 286 } 287 /* 288 * Changing the ownership probably won't succeed, unless we're root 289 * or POSIX_CHOWN_RESTRICTED is not set. Set uid/gid before setting 290 * the mode; current BSD behavior is to remove all setuid bits on 291 * chown. If chown fails, lose setuid/setgid bits. 292 */ 293 if (fd >= 0 ? fchown(fd, fs->st_uid, fs->st_gid) : 294 lchown(to.p_path, fs->st_uid, fs->st_gid)) { 295 if (errno != EPERM) { 296 warn("chown: %s", to.p_path); 297 rval = 1; 298 } 299 fs->st_mode &= ~(S_ISTXT | S_ISUID | S_ISGID); 300 } 301 if (fd >= 0 ? fchmod(fd, fs->st_mode) : 302 fchmodat(AT_FDCWD, to.p_path, fs->st_mode, AT_SYMLINK_NOFOLLOW)) { 303 warn("chmod: %s", to.p_path); 304 rval = 1; 305 } 306 307 /* 308 * XXX 309 * NFS doesn't support chflags; ignore errors unless there's reason 310 * to believe we're losing bits. (Note, this still won't be right 311 * if the server supports flags and we were trying to *remove* flags 312 * on a file that we copied, i.e., that we didn't create.) 313 */ 314 errno = 0; 315 if (fd >= 0 ? fchflags(fd, fs->st_flags) : 316 chflagsat(AT_FDCWD, to.p_path, fs->st_flags, AT_SYMLINK_NOFOLLOW)) 317 if (errno != EOPNOTSUPP || fs->st_flags != 0) { 318 warn("chflags: %s", to.p_path); 319 rval = 1; 320 } 321 return (rval); 322 } 323 324 325 void 326 usage(void) 327 { 328 (void)fprintf(stderr, 329 "usage: %s [-afipv] [-R [-H | -L | -P]] source target\n", __progname); 330 (void)fprintf(stderr, 331 " %s [-afipv] [-R [-H | -L | -P]] source ... directory\n", 332 __progname); 333 exit(1); 334 } 335