xref: /freebsd/sbin/ldconfig/ldconfig.c (revision b601c69bdbe8755d26570261d7fd4c02ee4eff74)
1 /*
2  * Copyright (c) 1993,1995 Paul Kranenburg
3  * 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 Paul Kranenburg.
16  * 4. The name of the author may not be used to endorse or promote products
17  *    derived from this software without specific prior written permission
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #ifndef lint
32 static const char rcsid[] =
33   "$FreeBSD$";
34 #endif /* not lint */
35 
36 #include <sys/param.h>
37 #include <sys/types.h>
38 #include <sys/stat.h>
39 #include <sys/mman.h>
40 #include <a.out.h>
41 #include <ctype.h>
42 #include <dirent.h>
43 #include <elf.h>
44 #include <err.h>
45 #include <errno.h>
46 #include <fcntl.h>
47 #include <link.h>
48 #include <objformat.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <unistd.h>
53 
54 #include "ldconfig.h"
55 #include "shlib.h"
56 #include "support.h"
57 
58 #if DEBUG
59 /* test */
60 #undef _PATH_LD_HINTS
61 #define _PATH_LD_HINTS		"./ld.so.hints"
62 #undef _PATH_ELF_HINTS
63 #define _PATH_ELF_HINTS		"./ld-elf.so.hints"
64 #endif
65 
66 #undef major
67 #undef minor
68 
69 static int			verbose;
70 static int			nostd;
71 static int			justread;
72 static int			merge;
73 static int			rescan;
74 static char			*hints_file;
75 
76 struct shlib_list {
77 	/* Internal list of shared libraries found */
78 	char			*name;
79 	char			*path;
80 	int			dewey[MAXDEWEY];
81 	int			ndewey;
82 #define major dewey[0]
83 #define minor dewey[1]
84 	struct shlib_list	*next;
85 };
86 
87 static struct shlib_list	*shlib_head = NULL, **shlib_tail = &shlib_head;
88 static char			*dir_list;
89 
90 static int		buildhints __P((void));
91 static int		dodir __P((char *, int));
92 int			dofile __P((char *, int));
93 static void		enter __P((char *, char *, char *, int *, int));
94 static void		listhints __P((void));
95 static int		readhints __P((void));
96 static void		usage __P((void));
97 
98 int
99 main(argc, argv)
100 int	argc;
101 char	*argv[];
102 {
103 	int		i, c;
104 	int		rval = 0;
105 	char		objformat[32];
106 	int		is_aout;
107 
108 	if (getobjformat(objformat, sizeof objformat, &argc, argv) == -1)
109 		errx(1, "getobjformat failed: name too long");
110 	if (strcmp(objformat, "aout") == 0)
111 		is_aout = 1;
112 	else if (strcmp(objformat, "elf") == 0)
113 		is_aout = 0;
114 	else
115 		errx(1, "unknown object format \"%s\"", objformat);
116 
117 	hints_file = is_aout ? _PATH_LD_HINTS : _PATH_ELF_HINTS;
118 	if (argc == 1)
119 		rescan = 1;
120 	else while((c = getopt(argc, argv, "Rf:mrsv")) != -1) {
121 		switch (c) {
122 		case 'R':
123 			rescan = 1;
124 			break;
125 		case 'f':
126 			hints_file = optarg;
127 			break;
128 		case 'm':
129 			merge = 1;
130 			break;
131 		case 'r':
132 			justread = 1;
133 			break;
134 		case 's':
135 			nostd = 1;
136 			break;
137 		case 'v':
138 			verbose = 1;
139 			break;
140 		default:
141 			usage();
142 			break;
143 		}
144 	}
145 
146 	if (!is_aout) {
147 		if (justread)
148 			list_elf_hints(hints_file);
149 		else
150 			update_elf_hints(hints_file, argc - optind,
151 			    argv + optind, merge || rescan);
152 		return 0;
153 	}
154 
155 	dir_list = strdup("");
156 
157 	if (justread || merge || rescan) {
158 		if ((rval = readhints()) != 0)
159 			return rval;
160 	}
161 
162 	if (!nostd && !merge && !rescan)
163 		std_search_path();
164 
165 	/* Add any directories/files from the command line */
166 	if (!justread) {
167 		for (i = optind; i < argc; i++) {
168 			struct stat stbuf;
169 
170 			if (stat(argv[i], &stbuf) == -1) {
171 				warn("%s", argv[i]);
172 				rval = -1;
173 			} else if (strcmp(argv[i], "/usr/lib") == 0) {
174 				warnx("WARNING! '%s' can not be used", argv[i]);
175 				rval = -1;
176 			} else {
177 				/*
178 				 * See if this is a directory-containing
179 				 * file instead of a directory
180 				 */
181 				if (S_ISREG(stbuf.st_mode))
182 					rval |= dofile(argv[i], 0);
183 				else
184 					add_search_path(argv[i]);
185 			}
186 		}
187 	}
188 
189 	for (i = 0; i < n_search_dirs; i++) {
190 		char *cp = concat(dir_list, *dir_list?":":"", search_dirs[i]);
191 		free(dir_list);
192 		dir_list = cp;
193 	}
194 
195 	if (justread) {
196 		listhints();
197 		return 0;
198 	}
199 
200 	for (i = 0; i < n_search_dirs; i++)
201 		rval |= dodir(search_dirs[i], 1);
202 
203 	rval |= buildhints();
204 
205 	return rval;
206 }
207 
208 static void
209 usage()
210 {
211 	fprintf(stderr,
212 	"usage: ldconfig [-aout | -elf] [-Rmrsv] [-f hints_file] [dir | file ...]\n");
213 	exit(1);
214 }
215 
216 int
217 dofile(fname, silent)
218 char	*fname;
219 int	silent;
220 {
221 	FILE *hfp;
222 	char buf[MAXPATHLEN];
223 	int rval = 0;
224 	char *cp, *sp;
225 
226 	if ((hfp = fopen(fname, "r")) == NULL) {
227 		warn("%s", fname);
228 		return -1;
229 	}
230 
231 	while (fgets(buf, sizeof(buf), hfp)) {
232 		cp = buf;
233 		while (isspace(*cp))
234 			cp++;
235 		if (*cp == '#' || *cp == '\0')
236 			continue;
237 		sp = cp;
238 		while (!isspace(*cp) && *cp != '\0')
239 			cp++;
240 
241 		if (*cp != '\n') {
242 			*cp = '\0';
243 			warnx("%s: trailing characters ignored", sp);
244 		}
245 
246 		*cp = '\0';
247 
248 		rval |= dodir(sp, silent);
249 	}
250 
251 	(void)fclose(hfp);
252 	return rval;
253 }
254 
255 int
256 dodir(dir, silent)
257 char	*dir;
258 int	silent;
259 {
260 	DIR		*dd;
261 	struct dirent	*dp;
262 	char		name[MAXPATHLEN];
263 	int		dewey[MAXDEWEY], ndewey;
264 
265 	if ((dd = opendir(dir)) == NULL) {
266 		if (silent && errno == ENOENT)	/* Ignore the error */
267 			return 0;
268 		warn("%s", dir);
269 		return -1;
270 	}
271 
272 	while ((dp = readdir(dd)) != NULL) {
273 		register int n;
274 		register char *cp;
275 
276 		/* Check for `lib' prefix */
277 		if (dp->d_name[0] != 'l' ||
278 		    dp->d_name[1] != 'i' ||
279 		    dp->d_name[2] != 'b')
280 			continue;
281 
282 		/* Copy the entry minus prefix */
283 		(void)strcpy(name, dp->d_name + 3);
284 		n = strlen(name);
285 		if (n < 4)
286 			continue;
287 
288 		/* Find ".so." in name */
289 		for (cp = name + n - 4; cp > name; --cp) {
290 			if (cp[0] == '.' &&
291 			    cp[1] == 's' &&
292 			    cp[2] == 'o' &&
293 			    cp[3] == '.')
294 				break;
295 		}
296 		if (cp <= name)
297 			continue;
298 
299 		*cp = '\0';
300 		if (!isdigit(*(cp+4)))
301 			continue;
302 
303 		bzero((caddr_t)dewey, sizeof(dewey));
304 		ndewey = getdewey(dewey, cp + 4);
305 		if (ndewey < 2)
306 			continue;
307 		enter(dir, dp->d_name, name, dewey, ndewey);
308 	}
309 
310 	closedir(dd);
311 	return 0;
312 }
313 
314 static void
315 enter(dir, file, name, dewey, ndewey)
316 char	*dir, *file, *name;
317 int	dewey[], ndewey;
318 {
319 	struct shlib_list	*shp;
320 
321 	for (shp = shlib_head; shp; shp = shp->next) {
322 		if (strcmp(name, shp->name) != 0 || major != shp->major)
323 			continue;
324 
325 		/* Name matches existing entry */
326 		if (cmpndewey(dewey, ndewey, shp->dewey, shp->ndewey) > 0) {
327 
328 			/* Update this entry with higher versioned lib */
329 			if (verbose)
330 				printf("Updating lib%s.%d.%d to %s/%s\n",
331 					shp->name, shp->major, shp->minor,
332 					dir, file);
333 
334 			free(shp->name);
335 			shp->name = strdup(name);
336 			free(shp->path);
337 			shp->path = concat(dir, "/", file);
338 			bcopy(dewey, shp->dewey, sizeof(shp->dewey));
339 			shp->ndewey = ndewey;
340 		}
341 		break;
342 	}
343 
344 	if (shp)
345 		/* Name exists: older version or just updated */
346 		return;
347 
348 	/* Allocate new list element */
349 	if (verbose)
350 		printf("Adding %s/%s\n", dir, file);
351 
352 	shp = (struct shlib_list *)xmalloc(sizeof *shp);
353 	shp->name = strdup(name);
354 	shp->path = concat(dir, "/", file);
355 	bcopy(dewey, shp->dewey, MAXDEWEY);
356 	shp->ndewey = ndewey;
357 	shp->next = NULL;
358 
359 	*shlib_tail = shp;
360 	shlib_tail = &shp->next;
361 }
362 
363 
364 int
365 hinthash(cp, vmajor)
366 char	*cp;
367 int	vmajor;
368 {
369 	int	k = 0;
370 
371 	while (*cp)
372 		k = (((k << 1) + (k >> 14)) ^ (*cp++)) & 0x3fff;
373 
374 	k = (((k << 1) + (k >> 14)) ^ (vmajor*257)) & 0x3fff;
375 
376 	return k;
377 }
378 
379 int
380 buildhints()
381 {
382 	struct hints_header	hdr;
383 	struct hints_bucket	*blist;
384 	struct shlib_list	*shp;
385 	char			*strtab;
386 	int			i, n, str_index = 0;
387 	int			strtab_sz = 0;	/* Total length of strings */
388 	int			nhints = 0;	/* Total number of hints */
389 	int			fd;
390 	char			*tmpfile;
391 
392 	for (shp = shlib_head; shp; shp = shp->next) {
393 		strtab_sz += 1 + strlen(shp->name);
394 		strtab_sz += 1 + strlen(shp->path);
395 		nhints++;
396 	}
397 
398 	/* Fill hints file header */
399 	hdr.hh_magic = HH_MAGIC;
400 	hdr.hh_version = LD_HINTS_VERSION_2;
401 	hdr.hh_nbucket = 1 * nhints;
402 	n = hdr.hh_nbucket * sizeof(struct hints_bucket);
403 	hdr.hh_hashtab = sizeof(struct hints_header);
404 	hdr.hh_strtab = hdr.hh_hashtab + n;
405 	hdr.hh_dirlist = strtab_sz;
406 	strtab_sz += 1 + strlen(dir_list);
407 	hdr.hh_strtab_sz = strtab_sz;
408 	hdr.hh_ehints = hdr.hh_strtab + hdr.hh_strtab_sz;
409 
410 	if (verbose)
411 		printf("Totals: entries %d, buckets %ld, string size %d\n",
412 			nhints, (long)hdr.hh_nbucket, strtab_sz);
413 
414 	/* Allocate buckets and string table */
415 	blist = (struct hints_bucket *)xmalloc(n);
416 	bzero((char *)blist, n);
417 	for (i = 0; i < hdr.hh_nbucket; i++)
418 		/* Empty all buckets */
419 		blist[i].hi_next = -1;
420 
421 	strtab = (char *)xmalloc(strtab_sz);
422 
423 	/* Enter all */
424 	for (shp = shlib_head; shp; shp = shp->next) {
425 		struct hints_bucket	*bp;
426 
427 		bp = blist +
428 		  (hinthash(shp->name, shp->major) % hdr.hh_nbucket);
429 
430 		if (bp->hi_pathx) {
431 			int	i;
432 
433 			for (i = 0; i < hdr.hh_nbucket; i++) {
434 				if (blist[i].hi_pathx == 0)
435 					break;
436 			}
437 			if (i == hdr.hh_nbucket) {
438 				warnx("bummer!");
439 				return -1;
440 			}
441 			while (bp->hi_next != -1)
442 				bp = &blist[bp->hi_next];
443 			bp->hi_next = i;
444 			bp = blist + i;
445 		}
446 
447 		/* Insert strings in string table */
448 		bp->hi_namex = str_index;
449 		strcpy(strtab + str_index, shp->name);
450 		str_index += 1 + strlen(shp->name);
451 
452 		bp->hi_pathx = str_index;
453 		strcpy(strtab + str_index, shp->path);
454 		str_index += 1 + strlen(shp->path);
455 
456 		/* Copy versions */
457 		bcopy(shp->dewey, bp->hi_dewey, sizeof(bp->hi_dewey));
458 		bp->hi_ndewey = shp->ndewey;
459 	}
460 
461 	/* Copy search directories */
462 	strcpy(strtab + str_index, dir_list);
463 	str_index += 1 + strlen(dir_list);
464 
465 	/* Sanity check */
466 	if (str_index != strtab_sz) {
467 		errx(1, "str_index(%d) != strtab_sz(%d)", str_index, strtab_sz);
468 	}
469 
470 	tmpfile = concat(hints_file, ".XXXXXXXXXX", "");
471 	umask(0);	/* Create with exact permissions */
472 	if ((fd = mkstemp(tmpfile)) == -1) {
473 		warn("%s", tmpfile);
474 		return -1;
475 	}
476 	fchmod(fd, 0444);
477 
478 	if (write(fd, &hdr, sizeof(struct hints_header)) !=
479 						sizeof(struct hints_header)) {
480 		warn("%s", hints_file);
481 		return -1;
482 	}
483 	if (write(fd, blist, hdr.hh_nbucket * sizeof(struct hints_bucket)) !=
484 				hdr.hh_nbucket * sizeof(struct hints_bucket)) {
485 		warn("%s", hints_file);
486 		return -1;
487 	}
488 	if (write(fd, strtab, strtab_sz) != strtab_sz) {
489 		warn("%s", hints_file);
490 		return -1;
491 	}
492 	if (close(fd) != 0) {
493 		warn("%s", hints_file);
494 		return -1;
495 	}
496 
497 	/* Install it */
498 	if (unlink(hints_file) != 0 && errno != ENOENT) {
499 		warn("%s", hints_file);
500 		return -1;
501 	}
502 
503 	if (rename(tmpfile, hints_file) != 0) {
504 		warn("%s", hints_file);
505 		return -1;
506 	}
507 
508 	return 0;
509 }
510 
511 static int
512 readhints()
513 {
514 	int			fd;
515 	void			*addr;
516 	long			fsize;
517 	long			msize;
518 	struct hints_header	*hdr;
519 	struct hints_bucket	*blist;
520 	char			*strtab;
521 	struct shlib_list	*shp;
522 	int			i;
523 
524 	if ((fd = open(hints_file, O_RDONLY, 0)) == -1) {
525 		warn("%s", hints_file);
526 		return -1;
527 	}
528 
529 	msize = PAGE_SIZE;
530 	addr = mmap(0, msize, PROT_READ, MAP_COPY, fd, 0);
531 
532 	if (addr == MAP_FAILED) {
533 		warn("%s", hints_file);
534 		return -1;
535 	}
536 
537 	hdr = (struct hints_header *)addr;
538 	if (HH_BADMAG(*hdr)) {
539 		warnx("%s: bad magic: %lo", hints_file,
540 			(unsigned long)hdr->hh_magic);
541 		return -1;
542 	}
543 
544 	if (hdr->hh_version != LD_HINTS_VERSION_1 &&
545 	    hdr->hh_version != LD_HINTS_VERSION_2) {
546 		warnx("unsupported version: %ld", (long)hdr->hh_version);
547 		return -1;
548 	}
549 
550 	if (hdr->hh_ehints > msize) {
551 		fsize = hdr->hh_ehints;
552 		munmap(addr, msize);
553 		addr = mmap(0, fsize, PROT_READ, MAP_COPY, fd, 0);
554 		if (addr == MAP_FAILED) {
555 			warn("%s", hints_file);
556 			return -1;
557 		}
558 		hdr = (struct hints_header *)addr;
559 	}
560 	close(fd);
561 
562 	blist = (struct hints_bucket *)(addr + hdr->hh_hashtab);
563 	strtab = (char *)(addr + hdr->hh_strtab);
564 
565 	if (hdr->hh_version >= LD_HINTS_VERSION_2)
566 		add_search_path(strtab + hdr->hh_dirlist);
567 	else if (rescan)
568 		errx(1, "%s too old and does not contain the search path",
569 			hints_file);
570 
571 	if (rescan)
572 		return 0;
573 
574 	for (i = 0; i < hdr->hh_nbucket; i++) {
575 		struct hints_bucket	*bp = &blist[i];
576 
577 		/* Sanity check */
578 		if (bp->hi_namex >= hdr->hh_strtab_sz) {
579 			warnx("bad name index: %#x", bp->hi_namex);
580 			return -1;
581 		}
582 		if (bp->hi_pathx >= hdr->hh_strtab_sz) {
583 			warnx("bad path index: %#x", bp->hi_pathx);
584 			return -1;
585 		}
586 
587 		/* Allocate new list element */
588 		shp = (struct shlib_list *)xmalloc(sizeof *shp);
589 		shp->name = strdup(strtab + bp->hi_namex);
590 		shp->path = strdup(strtab + bp->hi_pathx);
591 		bcopy(bp->hi_dewey, shp->dewey, sizeof(shp->dewey));
592 		shp->ndewey = bp->hi_ndewey;
593 		shp->next = NULL;
594 
595 		*shlib_tail = shp;
596 		shlib_tail = &shp->next;
597 	}
598 
599 	return 0;
600 }
601 
602 static void
603 listhints()
604 {
605 	struct shlib_list	*shp;
606 	int			i;
607 
608 	printf("%s:\n", hints_file);
609 	printf("\tsearch directories: %s\n", dir_list);
610 
611 	for (i = 0, shp = shlib_head; shp; i++, shp = shp->next)
612 		printf("\t%d:-l%s.%d.%d => %s\n",
613 			i, shp->name, shp->major, shp->minor, shp->path);
614 
615 	return;
616 }
617