xref: /freebsd/sbin/ldconfig/ldconfig.c (revision 2493aadadee50ababced80d22d8654eaaeaa7909)
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-hints.h>
44 #include <err.h>
45 #include <errno.h>
46 #include <fcntl.h>
47 #include <sys/link_aout.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52 
53 #include "ldconfig.h"
54 #include "shlib.h"
55 #include "support.h"
56 
57 #if DEBUG
58 /* test */
59 #undef _PATH_LD_HINTS
60 #define _PATH_LD_HINTS		"./ld.so.hints"
61 #undef _PATH_ELF_HINTS
62 #define _PATH_ELF_HINTS		"./ld-elf.so.hints"
63 #endif
64 
65 #define	_PATH_LD32_HINTS	"/var/run/ld32.so.hints"
66 #define	_PATH_ELF32_HINTS	"/var/run/ld-elf32.so.hints"
67 
68 #undef major
69 #undef minor
70 
71 static int			verbose;
72 static int			nostd;
73 static int			justread;
74 static int			merge;
75 static int			rescan;
76 static const char		*hints_file;
77 
78 struct shlib_list {
79 	/* Internal list of shared libraries found */
80 	char			*name;
81 	char			*path;
82 	int			dewey[MAXDEWEY];
83 	int			ndewey;
84 #define major dewey[0]
85 #define minor dewey[1]
86 	struct shlib_list	*next;
87 };
88 
89 static struct shlib_list	*shlib_head = NULL, **shlib_tail = &shlib_head;
90 static char			*dir_list;
91 
92 static int		buildhints(void);
93 static int		dodir(char *, int);
94 int			dofile(char *, int);
95 static void		enter(char *, char *, char *, int *, int);
96 static void		listhints(void);
97 static int		readhints(void);
98 static void		usage(void);
99 
100 /*
101  * Note on aout/a.out support.
102  * To properly support shared libraries for compat2x, which are a.out, we need
103  * to support a.out here.  As of 2013, bug reports are still coming in for this
104  * feature (on amd64 no less), so we know it is still in use.
105  */
106 
107 int
108 main(int argc, char **argv)
109 {
110 	int		i, c;
111 	int		rval = 0;
112 	int		is_aout = 0;
113 	int		is_32 = 0;
114 
115 	while (argc > 1) {
116 		if (strcmp(argv[1], "-aout") == 0) {
117 			is_aout = 1;
118 			argc--;
119 			argv++;
120 		} else if (strcmp(argv[1], "-elf") == 0) {
121 			is_aout = 0;
122 			argc--;
123 			argv++;
124 		} else if (strcmp(argv[1], "-32") == 0) {
125 			is_32 = 1;
126 			argc--;
127 			argv++;
128 		} else {
129 			break;
130 		}
131 	}
132 
133 	if (is_32)
134 		hints_file = is_aout ? _PATH_LD32_HINTS : _PATH_ELF32_HINTS;
135 	else
136 		hints_file = is_aout ? _PATH_LD_HINTS : _PATH_ELF_HINTS;
137 	if (argc == 1)
138 		rescan = 1;
139 	else while((c = getopt(argc, argv, "Rf:imrsv")) != -1) {
140 		switch (c) {
141 		case 'R':
142 			rescan = 1;
143 			break;
144 		case 'f':
145 			hints_file = optarg;
146 			break;
147 		case 'i':
148 			insecure = 1;
149 			break;
150 		case 'm':
151 			merge = 1;
152 			break;
153 		case 'r':
154 			justread = 1;
155 			break;
156 		case 's':
157 			nostd = 1;
158 			break;
159 		case 'v':
160 			verbose = 1;
161 			break;
162 		default:
163 			usage();
164 			break;
165 		}
166 	}
167 
168 	if (!is_aout) {
169 		if (justread)
170 			list_elf_hints(hints_file);
171 		else
172 			update_elf_hints(hints_file, argc - optind,
173 			    argv + optind, merge || rescan);
174 		return 0;
175 	}
176 
177 	/* Here begins the aout libs processing */
178 	dir_list = strdup("");
179 
180 	if (justread || merge || rescan) {
181 		if ((rval = readhints()) != 0)
182 			return rval;
183 	}
184 
185 	if (!nostd && !merge && !rescan)
186 		std_search_path();
187 
188 	/* Add any directories/files from the command line */
189 	if (!justread) {
190 		for (i = optind; i < argc; i++) {
191 			struct stat stbuf;
192 
193 			if (stat(argv[i], &stbuf) == -1) {
194 				warn("%s", argv[i]);
195 				rval = -1;
196 			} else if (strcmp(argv[i], "/usr/lib") == 0) {
197 				warnx("WARNING! '%s' can not be used", argv[i]);
198 				rval = -1;
199 			} else {
200 				/*
201 				 * See if this is a directory-containing
202 				 * file instead of a directory
203 				 */
204 				if (S_ISREG(stbuf.st_mode))
205 					rval |= dofile(argv[i], 0);
206 				else
207 					add_search_path(argv[i]);
208 			}
209 		}
210 	}
211 
212 	for (i = 0; i < n_search_dirs; i++) {
213 		char *cp = concat(dir_list, *dir_list?":":"", search_dirs[i]);
214 		free(dir_list);
215 		dir_list = cp;
216 	}
217 
218 	if (justread) {
219 		listhints();
220 		return 0;
221 	}
222 
223 	for (i = 0; i < n_search_dirs; i++)
224 		rval |= dodir(search_dirs[i], 1);
225 
226 	rval |= buildhints();
227 
228 	return rval;
229 }
230 
231 static void
232 usage(void)
233 {
234 	fprintf(stderr,
235 	"usage: ldconfig [-32] [-aout | -elf] [-Rimrsv] [-f hints_file] [directory | file ...]\n");
236 	exit(1);
237 }
238 
239 int
240 dofile(char *fname, int silent)
241 {
242 	FILE *hfp;
243 	char buf[MAXPATHLEN];
244 	int rval = 0;
245 	char *cp, *sp;
246 
247 	if ((hfp = fopen(fname, "r")) == NULL) {
248 		warn("%s", fname);
249 		return -1;
250 	}
251 
252 	while (fgets(buf, sizeof(buf), hfp)) {
253 		cp = buf;
254 		while (isspace(*cp))
255 			cp++;
256 		if (*cp == '#' || *cp == '\0')
257 			continue;
258 		sp = cp;
259 		while (!isspace(*cp) && *cp != '\0')
260 			cp++;
261 
262 		if (*cp != '\n') {
263 			*cp = '\0';
264 			warnx("%s: trailing characters ignored", sp);
265 		}
266 
267 		*cp = '\0';
268 
269 		rval |= dodir(sp, silent);
270 	}
271 
272 	(void)fclose(hfp);
273 	return rval;
274 }
275 
276 int
277 dodir(char *dir, int silent)
278 {
279 	DIR		*dd;
280 	struct dirent	*dp;
281 	char		name[MAXPATHLEN];
282 	int		dewey[MAXDEWEY], ndewey;
283 
284 	if ((dd = opendir(dir)) == NULL) {
285 		if (silent && errno == ENOENT)	/* Ignore the error */
286 			return 0;
287 		warn("%s", dir);
288 		return -1;
289 	}
290 
291 	while ((dp = readdir(dd)) != NULL) {
292 		int n;
293 		char *cp;
294 
295 		/* Check for `lib' prefix */
296 		if (dp->d_name[0] != 'l' ||
297 		    dp->d_name[1] != 'i' ||
298 		    dp->d_name[2] != 'b')
299 			continue;
300 
301 		/* Copy the entry minus prefix */
302 		(void)strcpy(name, dp->d_name + 3);
303 		n = strlen(name);
304 		if (n < 4)
305 			continue;
306 
307 		/* Find ".so." in name */
308 		for (cp = name + n - 4; cp > name; --cp) {
309 			if (cp[0] == '.' &&
310 			    cp[1] == 's' &&
311 			    cp[2] == 'o' &&
312 			    cp[3] == '.')
313 				break;
314 		}
315 		if (cp <= name)
316 			continue;
317 
318 		*cp = '\0';
319 		if (!isdigit(*(cp+4)))
320 			continue;
321 
322 		bzero((caddr_t)dewey, sizeof(dewey));
323 		ndewey = getdewey(dewey, cp + 4);
324 		if (ndewey < 2)
325 			continue;
326 		enter(dir, dp->d_name, name, dewey, ndewey);
327 	}
328 
329 	closedir(dd);
330 	return 0;
331 }
332 
333 static void
334 enter(char *dir, char *file, char *name, int dewey[], int ndewey)
335 {
336 	struct shlib_list	*shp;
337 
338 	for (shp = shlib_head; shp; shp = shp->next) {
339 		if (strcmp(name, shp->name) != 0 || major != shp->major)
340 			continue;
341 
342 		/* Name matches existing entry */
343 		if (cmpndewey(dewey, ndewey, shp->dewey, shp->ndewey) > 0) {
344 
345 			/* Update this entry with higher versioned lib */
346 			if (verbose)
347 				printf("Updating lib%s.%d.%d to %s/%s\n",
348 					shp->name, shp->major, shp->minor,
349 					dir, file);
350 
351 			free(shp->name);
352 			shp->name = strdup(name);
353 			free(shp->path);
354 			shp->path = concat(dir, "/", file);
355 			bcopy(dewey, shp->dewey, sizeof(shp->dewey));
356 			shp->ndewey = ndewey;
357 		}
358 		break;
359 	}
360 
361 	if (shp)
362 		/* Name exists: older version or just updated */
363 		return;
364 
365 	/* Allocate new list element */
366 	if (verbose)
367 		printf("Adding %s/%s\n", dir, file);
368 
369 	shp = (struct shlib_list *)xmalloc(sizeof *shp);
370 	shp->name = strdup(name);
371 	shp->path = concat(dir, "/", file);
372 	bcopy(dewey, shp->dewey, sizeof(shp->dewey));
373 	shp->ndewey = ndewey;
374 	shp->next = NULL;
375 
376 	*shlib_tail = shp;
377 	shlib_tail = &shp->next;
378 }
379 
380 
381 static int
382 hinthash(char *cp, int vmajor)
383 {
384 	int	k = 0;
385 
386 	while (*cp)
387 		k = (((k << 1) + (k >> 14)) ^ (*cp++)) & 0x3fff;
388 
389 	k = (((k << 1) + (k >> 14)) ^ (vmajor*257)) & 0x3fff;
390 
391 	return k;
392 }
393 
394 int
395 buildhints(void)
396 {
397 	struct hints_header	hdr;
398 	struct hints_bucket	*blist;
399 	struct shlib_list	*shp;
400 	char			*strtab;
401 	int			i, n, str_index = 0;
402 	int			strtab_sz = 0;	/* Total length of strings */
403 	int			nhints = 0;	/* Total number of hints */
404 	int			fd;
405 	char			*tmpfilename;
406 
407 	for (shp = shlib_head; shp; shp = shp->next) {
408 		strtab_sz += 1 + strlen(shp->name);
409 		strtab_sz += 1 + strlen(shp->path);
410 		nhints++;
411 	}
412 
413 	/* Fill hints file header */
414 	hdr.hh_magic = HH_MAGIC;
415 	hdr.hh_version = LD_HINTS_VERSION_2;
416 	hdr.hh_nbucket = 1 * nhints;
417 	n = hdr.hh_nbucket * sizeof(struct hints_bucket);
418 	hdr.hh_hashtab = sizeof(struct hints_header);
419 	hdr.hh_strtab = hdr.hh_hashtab + n;
420 	hdr.hh_dirlist = strtab_sz;
421 	strtab_sz += 1 + strlen(dir_list);
422 	hdr.hh_strtab_sz = strtab_sz;
423 	hdr.hh_ehints = hdr.hh_strtab + hdr.hh_strtab_sz;
424 
425 	if (verbose)
426 		printf("Totals: entries %d, buckets %ld, string size %d\n",
427 			nhints, (long)hdr.hh_nbucket, strtab_sz);
428 
429 	/* Allocate buckets and string table */
430 	blist = (struct hints_bucket *)xmalloc(n);
431 	bzero((char *)blist, n);
432 	for (i = 0; i < hdr.hh_nbucket; i++)
433 		/* Empty all buckets */
434 		blist[i].hi_next = -1;
435 
436 	strtab = (char *)xmalloc(strtab_sz);
437 
438 	/* Enter all */
439 	for (shp = shlib_head; shp; shp = shp->next) {
440 		struct hints_bucket	*bp;
441 
442 		bp = blist +
443 		  (hinthash(shp->name, shp->major) % hdr.hh_nbucket);
444 
445 		if (bp->hi_pathx) {
446 			int	j;
447 
448 			for (j = 0; j < hdr.hh_nbucket; j++) {
449 				if (blist[j].hi_pathx == 0)
450 					break;
451 			}
452 			if (j == hdr.hh_nbucket) {
453 				warnx("bummer!");
454 				return -1;
455 			}
456 			while (bp->hi_next != -1)
457 				bp = &blist[bp->hi_next];
458 			bp->hi_next = j;
459 			bp = blist + j;
460 		}
461 
462 		/* Insert strings in string table */
463 		bp->hi_namex = str_index;
464 		strcpy(strtab + str_index, shp->name);
465 		str_index += 1 + strlen(shp->name);
466 
467 		bp->hi_pathx = str_index;
468 		strcpy(strtab + str_index, shp->path);
469 		str_index += 1 + strlen(shp->path);
470 
471 		/* Copy versions */
472 		bcopy(shp->dewey, bp->hi_dewey, sizeof(bp->hi_dewey));
473 		bp->hi_ndewey = shp->ndewey;
474 	}
475 
476 	/* Copy search directories */
477 	strcpy(strtab + str_index, dir_list);
478 	str_index += 1 + strlen(dir_list);
479 
480 	/* Sanity check */
481 	if (str_index != strtab_sz) {
482 		errx(1, "str_index(%d) != strtab_sz(%d)", str_index, strtab_sz);
483 	}
484 
485 	tmpfilename = concat(hints_file, ".XXXXXXXXXX", "");
486 	umask(0);	/* Create with exact permissions */
487 	if ((fd = mkstemp(tmpfilename)) == -1) {
488 		warn("%s", tmpfilename);
489 		return -1;
490 	}
491 	fchmod(fd, 0444);
492 
493 	if (write(fd, &hdr, sizeof(struct hints_header)) !=
494 						sizeof(struct hints_header)) {
495 		warn("%s", hints_file);
496 		return -1;
497 	}
498 	if (write(fd, blist, hdr.hh_nbucket * sizeof(*blist)) !=
499 				(ssize_t)(hdr.hh_nbucket * sizeof(*blist))) {
500 		warn("%s", hints_file);
501 		return -1;
502 	}
503 	if (write(fd, strtab, strtab_sz) != strtab_sz) {
504 		warn("%s", hints_file);
505 		return -1;
506 	}
507 	if (close(fd) != 0) {
508 		warn("%s", hints_file);
509 		return -1;
510 	}
511 
512 	/* Install it */
513 	if (unlink(hints_file) != 0 && errno != ENOENT) {
514 		warn("%s", hints_file);
515 		return -1;
516 	}
517 
518 	if (rename(tmpfilename, hints_file) != 0) {
519 		warn("%s", hints_file);
520 		return -1;
521 	}
522 
523 	return 0;
524 }
525 
526 static int
527 readhints(void)
528 {
529 	int			fd;
530 	void			*addr;
531 	long			fsize;
532 	long			msize;
533 	struct hints_header	*hdr;
534 	struct hints_bucket	*blist;
535 	char			*strtab;
536 	struct shlib_list	*shp;
537 	int			i;
538 
539 	if ((fd = open(hints_file, O_RDONLY, 0)) == -1) {
540 		warn("%s", hints_file);
541 		return -1;
542 	}
543 
544 	msize = PAGE_SIZE;
545 	addr = mmap(0, msize, PROT_READ, MAP_COPY, fd, 0);
546 
547 	if (addr == MAP_FAILED) {
548 		warn("%s", hints_file);
549 		return -1;
550 	}
551 
552 	hdr = (struct hints_header *)addr;
553 	if (HH_BADMAG(*hdr)) {
554 		warnx("%s: bad magic: %lo", hints_file,
555 			(unsigned long)hdr->hh_magic);
556 		return -1;
557 	}
558 
559 	if (hdr->hh_version != LD_HINTS_VERSION_1 &&
560 	    hdr->hh_version != LD_HINTS_VERSION_2) {
561 		warnx("unsupported version: %ld", (long)hdr->hh_version);
562 		return -1;
563 	}
564 
565 	if (hdr->hh_ehints > msize) {
566 		fsize = hdr->hh_ehints;
567 		munmap(addr, msize);
568 		addr = mmap(0, fsize, PROT_READ, MAP_COPY, fd, 0);
569 		if (addr == MAP_FAILED) {
570 			warn("%s", hints_file);
571 			return -1;
572 		}
573 		hdr = (struct hints_header *)addr;
574 	}
575 	close(fd);
576 
577 	strtab = (char *)addr + hdr->hh_strtab;
578 
579 	if (hdr->hh_version >= LD_HINTS_VERSION_2)
580 		add_search_path(strtab + hdr->hh_dirlist);
581 	else if (rescan)
582 		errx(1, "%s too old and does not contain the search path",
583 			hints_file);
584 
585 	if (rescan)
586 		return 0;
587 
588 	blist = malloc(sizeof(*blist) * hdr->hh_nbucket);
589 	if (blist == NULL)
590 		err(1, "readhints");
591 	memcpy(blist, (char *)addr + hdr->hh_hashtab,
592 		sizeof(*blist) * hdr->hh_nbucket);
593 
594 
595 	for (i = 0; i < hdr->hh_nbucket; i++) {
596 		struct hints_bucket	*bp = &blist[i];
597 
598 		/* Sanity check */
599 		if (bp->hi_namex >= hdr->hh_strtab_sz) {
600 			warnx("bad name index: %#x", bp->hi_namex);
601 			free(blist);
602 			return -1;
603 		}
604 		if (bp->hi_pathx >= hdr->hh_strtab_sz) {
605 			warnx("bad path index: %#x", bp->hi_pathx);
606 			free(blist);
607 			return -1;
608 		}
609 
610 		/* Allocate new list element */
611 		shp = (struct shlib_list *)xmalloc(sizeof *shp);
612 		shp->name = strdup(strtab + bp->hi_namex);
613 		shp->path = strdup(strtab + bp->hi_pathx);
614 		bcopy(bp->hi_dewey, shp->dewey, sizeof(shp->dewey));
615 		shp->ndewey = bp->hi_ndewey;
616 		shp->next = NULL;
617 
618 		*shlib_tail = shp;
619 		shlib_tail = &shp->next;
620 	}
621 
622 	free(blist);
623 	return 0;
624 }
625 
626 static void
627 listhints(void)
628 {
629 	struct shlib_list	*shp;
630 	int			i;
631 
632 	printf("%s:\n", hints_file);
633 	printf("\tsearch directories: %s\n", dir_list);
634 
635 	for (i = 0, shp = shlib_head; shp; i++, shp = shp->next)
636 		printf("\t%d:-l%s.%d.%d => %s\n",
637 			i, shp->name, shp->major, shp->minor, shp->path);
638 
639 	return;
640 }
641