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      1 /* $NetBSD: utils.c,v 1.50 2024/01/15 17:41:06 christos Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 1991, 1993, 1994
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 #if 0
     35 static char sccsid[] = "@(#)utils.c	8.3 (Berkeley) 4/1/94";
     36 #else
     37 __RCSID("$NetBSD: utils.c,v 1.50 2024/01/15 17:41:06 christos Exp $");
     38 #endif
     39 #endif /* not lint */
     40 
     41 #define _ACL_PRIVATE
     42 #include <sys/mman.h>
     43 #include <sys/param.h>
     44 #include <sys/stat.h>
     45 #include <sys/time.h>
     46 #ifndef SMALL
     47 #include <sys/acl.h>
     48 #endif
     49 #include <sys/extattr.h>
     50 
     51 #include <err.h>
     52 #include <errno.h>
     53 #include <fcntl.h>
     54 #include <fts.h>
     55 #include <stdbool.h>
     56 #include <stdio.h>
     57 #include <stdlib.h>
     58 #include <string.h>
     59 #include <unistd.h>
     60 
     61 #include "extern.h"
     62 
     63 #define	MMAP_MAX_SIZE	(8 * 1048576)
     64 #define	MMAP_MAX_WRITE	(64 * 1024)
     65 
     66 int
     67 set_utimes(const char *file, struct stat *fs)
     68 {
     69     struct timespec ts[2];
     70 
     71     ts[0] = fs->st_atimespec;
     72     ts[1] = fs->st_mtimespec;
     73 
     74     if (lutimens(file, ts)) {
     75 	warn("lutimens: %s", file);
     76 	return (1);
     77     }
     78     return (0);
     79 }
     80 
     81 struct finfo {
     82 	const char *from;
     83 	const char *to;
     84 	off_t size;
     85 };
     86 
     87 static void
     88 progress(const struct finfo *fi, off_t written)
     89 {
     90 	int pcent = (int)((100.0 * written) / fi->size);
     91 
     92 	pinfo = 0;
     93 	(void)fprintf(stderr, "%s => %s %llu/%llu bytes %d%% written\n",
     94 	    fi->from, fi->to, (unsigned long long)written,
     95 	    (unsigned long long)fi->size, pcent);
     96 }
     97 
     98 int
     99 copy_file(FTSENT *entp, int dne)
    100 {
    101 	static char buf[MAXBSIZE];
    102 	struct stat to_stat, *fs;
    103 	int ch, checkch, from_fd, rcount, rval, to_fd, tolnk, wcount;
    104 	char *p;
    105 	off_t ptotal = 0;
    106 
    107 	/* if hard linking then simply link and return */
    108 	if (lflag) {
    109 		(void)unlink(to.p_path);
    110 		if (link(entp->fts_path, to.p_path)) {
    111 			warn("%s", to.p_path);
    112 			return (1);
    113 		}
    114 		return (0);
    115 	}
    116 
    117 	if ((from_fd = open(entp->fts_path, O_RDONLY, 0)) == -1) {
    118 		warn("%s", entp->fts_path);
    119 		return (1);
    120 	}
    121 
    122 	to_fd = -1;
    123 	fs = entp->fts_statp;
    124 	tolnk = ((Rflag && !(Lflag || Hflag)) || Pflag);
    125 
    126 	/*
    127 	 * If the file exists and we're interactive, verify with the user.
    128 	 * If the file DNE, set the mode to be the from file, minus setuid
    129 	 * bits, modified by the umask; arguably wrong, but it makes copying
    130 	 * executables work right and it's been that way forever.  (The
    131 	 * other choice is 666 or'ed with the execute bits on the from file
    132 	 * modified by the umask.)
    133 	 */
    134 	if (!dne) {
    135 		struct stat sb;
    136 		int sval;
    137 
    138 		if (iflag) {
    139 			(void)fprintf(stderr, "overwrite %s? ", to.p_path);
    140 			checkch = ch = getchar();
    141 			while (ch != '\n' && ch != EOF)
    142 				ch = getchar();
    143 			if (checkch != 'y' && checkch != 'Y') {
    144 				(void)close(from_fd);
    145 				return (0);
    146 			}
    147 		}
    148 
    149 		sval = tolnk ?
    150 			lstat(to.p_path, &sb) : stat(to.p_path, &sb);
    151 		if (sval == -1) {
    152 			warn("stat: %s", to.p_path);
    153 			(void)close(from_fd);
    154 			return (1);
    155 		}
    156 
    157 		if (!(tolnk && S_ISLNK(sb.st_mode)))
    158 			to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0);
    159 	} else
    160 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
    161 		    fs->st_mode & ~(S_ISUID | S_ISGID));
    162 
    163 	if (to_fd == -1 && (fflag || tolnk)) {
    164 		/*
    165 		 * attempt to remove existing destination file name and
    166 		 * create a new file
    167 		 */
    168 		(void)unlink(to.p_path);
    169 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
    170 			     fs->st_mode & ~(S_ISUID | S_ISGID));
    171 	}
    172 
    173 	if (to_fd == -1) {
    174 		warn("%s", to.p_path);
    175 		(void)close(from_fd);
    176 		return (1);
    177 	}
    178 
    179 	rval = 0;
    180 
    181 	/*
    182 	 * We always copy regular files, even if they appear to be 0-sized
    183 	 * because kernfs and procfs don't return file sizes.
    184 	 */
    185 	bool need_copy = S_ISREG(fs->st_mode) || fs->st_size > 0;
    186 
    187 	struct finfo fi;
    188 
    189 	fi.from = entp->fts_path;
    190 	fi.to = to.p_path;
    191 	fi.size = fs->st_size;
    192 
    193 	/*
    194 	 * Mmap and write if less than 8M (the limit is so
    195 	 * we don't totally trash memory on big files).
    196 	 * This is really a minor hack, but it wins some CPU back.
    197 	 */
    198 	if (S_ISREG(fs->st_mode) && fs->st_size && fs->st_size <= MMAP_MAX_SIZE) {
    199 		size_t fsize = (size_t)fs->st_size;
    200 		p = mmap(NULL, fsize, PROT_READ, MAP_FILE|MAP_SHARED,
    201 		    from_fd, (off_t)0);
    202 		if (p != MAP_FAILED) {
    203 			size_t remainder;
    204 
    205 			need_copy = false;
    206 
    207 			(void) madvise(p, (size_t)fs->st_size, MADV_SEQUENTIAL);
    208 
    209 			/*
    210 			 * Write out the data in small chunks to
    211 			 * avoid locking the output file for a
    212 			 * long time if the reading the data from
    213 			 * the source is slow.
    214 			 */
    215 			remainder = fsize;
    216 			do {
    217 				ssize_t chunk;
    218 
    219 				chunk = (remainder > MMAP_MAX_WRITE) ?
    220 				    MMAP_MAX_WRITE : remainder;
    221 				if (write(to_fd, &p[fsize - remainder],
    222 				    chunk) != chunk) {
    223 					warn("%s", to.p_path);
    224 					rval = 1;
    225 					break;
    226 				}
    227 				remainder -= chunk;
    228 				ptotal += chunk;
    229 				if (pinfo)
    230 					progress(&fi, ptotal);
    231 			} while (remainder > 0);
    232 
    233 			if (munmap(p, fsize) < 0) {
    234 				warn("%s", entp->fts_path);
    235 				rval = 1;
    236 			}
    237 		}
    238 	}
    239 
    240 	if (need_copy) {
    241 		while ((rcount = read(from_fd, buf, MAXBSIZE)) > 0) {
    242 			wcount = write(to_fd, buf, (size_t)rcount);
    243 			if (rcount != wcount || wcount == -1) {
    244 				warn("%s", to.p_path);
    245 				rval = 1;
    246 				break;
    247 			}
    248 			ptotal += wcount;
    249 			if (pinfo)
    250 				progress(&fi, ptotal);
    251 		}
    252 		if (rcount < 0) {
    253 			warn("%s", entp->fts_path);
    254 			rval = 1;
    255 		}
    256 	}
    257 
    258 	if (pflag && (fcpxattr(from_fd, to_fd) != 0))
    259 		warn("%s: error copying extended attributes", to.p_path);
    260 
    261 #ifndef SMALL
    262 	if (pflag && preserve_fd_acls(from_fd, to_fd) != 0)
    263 		rval = 1;
    264 #endif
    265 
    266 	(void)close(from_fd);
    267 
    268 	if (rval == 1) {
    269 		(void)close(to_fd);
    270 		return (1);
    271 	}
    272 
    273 	if (pflag && setfile(fs, to_fd))
    274 		rval = 1;
    275 	/*
    276 	 * If the source was setuid or setgid, lose the bits unless the
    277 	 * copy is owned by the same user and group.
    278 	 */
    279 #define	RETAINBITS \
    280 	(S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO)
    281 	if (!pflag && dne
    282 	    && fs->st_mode & (S_ISUID | S_ISGID) && fs->st_uid == myuid) {
    283 		if (fstat(to_fd, &to_stat)) {
    284 			warn("%s", to.p_path);
    285 			rval = 1;
    286 		} else if (fs->st_gid == to_stat.st_gid &&
    287 		    fchmod(to_fd, fs->st_mode & RETAINBITS & ~myumask)) {
    288 			warn("%s", to.p_path);
    289 			rval = 1;
    290 		}
    291 	}
    292 	if (close(to_fd)) {
    293 		warn("%s", to.p_path);
    294 		rval = 1;
    295 	}
    296 	/* set the mod/access times now after close of the fd */
    297 	if (pflag && set_utimes(to.p_path, fs)) {
    298 	    rval = 1;
    299 	}
    300 	return (rval);
    301 }
    302 
    303 int
    304 copy_link(FTSENT *p, int exists)
    305 {
    306 	int len;
    307 	char target[MAXPATHLEN];
    308 
    309 	if ((len = readlink(p->fts_path, target, sizeof(target)-1)) == -1) {
    310 		warn("readlink: %s", p->fts_path);
    311 		return (1);
    312 	}
    313 	target[len] = '\0';
    314 	if (exists && unlink(to.p_path)) {
    315 		warn("unlink: %s", to.p_path);
    316 		return (1);
    317 	}
    318 	if (symlink(target, to.p_path)) {
    319 		warn("symlink: %s", target);
    320 		return (1);
    321 	}
    322 	return (pflag ? setfile(p->fts_statp, 0) : 0);
    323 }
    324 
    325 int
    326 copy_fifo(struct stat *from_stat, int exists)
    327 {
    328 	if (exists && unlink(to.p_path)) {
    329 		warn("unlink: %s", to.p_path);
    330 		return (1);
    331 	}
    332 	if (mkfifo(to.p_path, from_stat->st_mode)) {
    333 		warn("mkfifo: %s", to.p_path);
    334 		return (1);
    335 	}
    336 	return (pflag ? setfile(from_stat, 0) : 0);
    337 }
    338 
    339 int
    340 copy_special(struct stat *from_stat, int exists)
    341 {
    342 	if (exists && unlink(to.p_path)) {
    343 		warn("unlink: %s", to.p_path);
    344 		return (1);
    345 	}
    346 	if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) {
    347 		warn("mknod: %s", to.p_path);
    348 		return (1);
    349 	}
    350 	return (pflag ? setfile(from_stat, 0) : 0);
    351 }
    352 
    353 
    354 /*
    355  * Function: setfile
    356  *
    357  * Purpose:
    358  *   Set the owner/group/permissions for the "to" file to the information
    359  *   in the stat structure.  If fd is zero, also call set_utimes() to set
    360  *   the mod/access times.  If fd is non-zero, the caller must do a utimes
    361  *   itself after close(fd).
    362  */
    363 int
    364 setfile(struct stat *fs, int fd)
    365 {
    366 	int rval, islink;
    367 
    368 	rval = 0;
    369 	islink = S_ISLNK(fs->st_mode);
    370 	fs->st_mode &= S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO;
    371 
    372 	/*
    373 	 * Changing the ownership probably won't succeed, unless we're root
    374 	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
    375 	 * the mode; current BSD behavior is to remove all setuid bits on
    376 	 * chown.  If chown fails, lose setuid/setgid bits.
    377 	 */
    378 	if (fd ? fchown(fd, fs->st_uid, fs->st_gid) :
    379 	    lchown(to.p_path, fs->st_uid, fs->st_gid)) {
    380 		if (errno != EPERM) {
    381 			warn("chown: %s", to.p_path);
    382 			rval = 1;
    383 		}
    384 		fs->st_mode &= ~(S_ISUID | S_ISGID);
    385 	}
    386 	if (fd ? fchmod(fd, fs->st_mode) : lchmod(to.p_path, fs->st_mode)) {
    387 		warn("chmod: %s", to.p_path);
    388 		rval = 1;
    389 	}
    390 
    391 	if (!islink && !Nflag) {
    392 		unsigned long fflags = fs->st_flags;
    393 		/*
    394 		 * XXX
    395 		 * NFS doesn't support chflags; ignore errors unless
    396 		 * there's reason to believe we're losing bits.
    397 		 * (Note, this still won't be right if the server
    398 		 * supports flags and we were trying to *remove* flags
    399 		 * on a file that we copied, i.e., that we didn't create.)
    400 		 */
    401 		errno = 0;
    402 		if ((fd ? fchflags(fd, fflags) :
    403 		    chflags(to.p_path, fflags)) == -1)
    404 			if (errno != EOPNOTSUPP || fs->st_flags != 0) {
    405 				warn("chflags: %s", to.p_path);
    406 				rval = 1;
    407 			}
    408 	}
    409 	/* if fd is non-zero, caller must call set_utimes() after close() */
    410 	if (fd == 0 && set_utimes(to.p_path, fs))
    411 	    rval = 1;
    412 	return (rval);
    413 }
    414 
    415 #ifndef SMALL
    416 int
    417 preserve_fd_acls(int source_fd, int dest_fd)
    418 {
    419 	acl_t acl;
    420 	acl_type_t acl_type;
    421 	int acl_supported = 0, ret, trivial;
    422 
    423 	ret = fpathconf(source_fd, _PC_ACL_NFS4);
    424 	if (ret > 0 ) {
    425 		acl_supported = 1;
    426 		acl_type = ACL_TYPE_NFS4;
    427 	} else if (ret < 0 && errno != EINVAL) {
    428 		warn("fpathconf(..., _PC_ACL_NFS4) failed for %s", to.p_path);
    429 		return (1);
    430 	}
    431 	if (acl_supported == 0) {
    432 		ret = fpathconf(source_fd, _PC_ACL_EXTENDED);
    433 		if (ret > 0 ) {
    434 			acl_supported = 1;
    435 			acl_type = ACL_TYPE_ACCESS;
    436 		} else if (ret < 0 && errno != EINVAL) {
    437 			warn("fpathconf(..., _PC_ACL_EXTENDED) failed for %s",
    438 			    to.p_path);
    439 			return (1);
    440 		}
    441 	}
    442 	if (acl_supported == 0)
    443 		return (0);
    444 
    445 	acl = acl_get_fd_np(source_fd, acl_type);
    446 	if (acl == NULL) {
    447 		warn("failed to get acl entries while setting %s", to.p_path);
    448 		return (1);
    449 	}
    450 	if (acl_is_trivial_np(acl, &trivial)) {
    451 		warn("acl_is_trivial() failed for %s", to.p_path);
    452 		acl_free(acl);
    453 		return (1);
    454 	}
    455 	if (trivial) {
    456 		acl_free(acl);
    457 		return (0);
    458 	}
    459 	if (acl_set_fd_np(dest_fd, acl, acl_type) < 0) {
    460 		warn("failed to set acl entries for %s", to.p_path);
    461 		acl_free(acl);
    462 		return (1);
    463 	}
    464 	acl_free(acl);
    465 	return (0);
    466 }
    467 
    468 int
    469 preserve_dir_acls(struct stat *fs, char *source_dir, char *dest_dir)
    470 {
    471 	acl_t (*aclgetf)(const char *, acl_type_t);
    472 	int (*aclsetf)(const char *, acl_type_t, acl_t);
    473 	struct acl *aclp;
    474 	acl_t acl;
    475 	acl_type_t acl_type;
    476 	int acl_supported = 0, ret, trivial;
    477 
    478 	ret = pathconf(source_dir, _PC_ACL_NFS4);
    479 	if (ret > 0) {
    480 		acl_supported = 1;
    481 		acl_type = ACL_TYPE_NFS4;
    482 	} else if (ret < 0 && errno != EINVAL) {
    483 		warn("fpathconf(..., _PC_ACL_NFS4) failed for %s", source_dir);
    484 		return (1);
    485 	}
    486 	if (acl_supported == 0) {
    487 		ret = pathconf(source_dir, _PC_ACL_EXTENDED);
    488 		if (ret > 0) {
    489 			acl_supported = 1;
    490 			acl_type = ACL_TYPE_ACCESS;
    491 		} else if (ret < 0 && errno != EINVAL) {
    492 			warn("fpathconf(..., _PC_ACL_EXTENDED) failed for %s",
    493 			    source_dir);
    494 			return (1);
    495 		}
    496 	}
    497 	if (acl_supported == 0)
    498 		return (0);
    499 
    500 	/*
    501 	 * If the file is a link we will not follow it.
    502 	 */
    503 	if (S_ISLNK(fs->st_mode)) {
    504 		aclgetf = acl_get_link_np;
    505 		aclsetf = acl_set_link_np;
    506 	} else {
    507 		aclgetf = acl_get_file;
    508 		aclsetf = acl_set_file;
    509 	}
    510 	if (acl_type == ACL_TYPE_ACCESS) {
    511 		/*
    512 		 * Even if there is no ACL_TYPE_DEFAULT entry here, a zero
    513 		 * size ACL will be returned. So it is not safe to simply
    514 		 * check the pointer to see if the default ACL is present.
    515 		 */
    516 		acl = aclgetf(source_dir, ACL_TYPE_DEFAULT);
    517 		if (acl == NULL) {
    518 			warn("failed to get default acl entries on %s",
    519 			    source_dir);
    520 			return (1);
    521 		}
    522 		aclp = &acl->ats_acl;
    523 		if (aclp->acl_cnt != 0 && aclsetf(dest_dir,
    524 		    ACL_TYPE_DEFAULT, acl) < 0) {
    525 			warn("failed to set default acl entries on %s",
    526 			    dest_dir);
    527 			acl_free(acl);
    528 			return (1);
    529 		}
    530 		acl_free(acl);
    531 	}
    532 	acl = aclgetf(source_dir, acl_type);
    533 	if (acl == NULL) {
    534 		warn("failed to get acl entries on %s", source_dir);
    535 		return (1);
    536 	}
    537 	if (acl_is_trivial_np(acl, &trivial)) {
    538 		warn("acl_is_trivial() failed on %s", source_dir);
    539 		acl_free(acl);
    540 		return (1);
    541 	}
    542 	if (trivial) {
    543 		acl_free(acl);
    544 		return (0);
    545 	}
    546 	if (aclsetf(dest_dir, acl_type, acl) < 0) {
    547 		warn("failed to set acl entries on %s", dest_dir);
    548 		acl_free(acl);
    549 		return (1);
    550 	}
    551 	acl_free(acl);
    552 	return (0);
    553 }
    554 #endif
    555 
    556 void
    557 usage(void)
    558 {
    559 	(void)fprintf(stderr,
    560 	    "usage: %s [-R [-H | -L | -P]] [-f | -i] [-alNpv] src target\n"
    561 	    "       %s [-R [-H | -L | -P]] [-f | -i] [-alNpv] src1 ... srcN directory\n",
    562 	    getprogname(), getprogname());
    563 	exit(1);
    564 	/* NOTREACHED */
    565 }
    566