xref: /freebsd/sbin/ldconfig/ldconfig.c (revision 1f4bcc459a76b7aa664f3fd557684cd0ba6da352)
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 #define	_PATH_ELFSOFT_HINTS	"/var/run/ld-elf-soft.so.hints"
68 
69 #undef major
70 #undef minor
71 
72 static int			verbose;
73 static int			nostd;
74 static int			justread;
75 static int			merge;
76 static int			rescan;
77 static const char		*hints_file;
78 
79 struct shlib_list {
80 	/* Internal list of shared libraries found */
81 	char			*name;
82 	char			*path;
83 	int			dewey[MAXDEWEY];
84 	int			ndewey;
85 #define major dewey[0]
86 #define minor dewey[1]
87 	struct shlib_list	*next;
88 };
89 
90 static struct shlib_list	*shlib_head = NULL, **shlib_tail = &shlib_head;
91 static char			*dir_list;
92 
93 static int		buildhints(void);
94 static int		dodir(char *, int);
95 int			dofile(char *, int);
96 static void		enter(char *, char *, char *, int *, int);
97 static void		listhints(void);
98 static int		readhints(void);
99 static void		usage(void);
100 
101 /*
102  * Note on aout/a.out support.
103  * To properly support shared libraries for compat2x, which are a.out, we need
104  * to support a.out here.  As of 2013, bug reports are still coming in for this
105  * feature (on amd64 no less), so we know it is still in use.
106  */
107 
108 int
109 main(int argc, char **argv)
110 {
111 	int		i, c;
112 	int		rval = 0;
113 	int		is_aout = 0;
114 	int		is_32 = 0;
115 	int		is_soft = 0;
116 
117 	while (argc > 1) {
118 		if (strcmp(argv[1], "-aout") == 0) {
119 			is_aout = 1;
120 			argc--;
121 			argv++;
122 		} else if (strcmp(argv[1], "-elf") == 0) {
123 			is_aout = 0;
124 			argc--;
125 			argv++;
126 		} else if (strcmp(argv[1], "-32") == 0) {
127 			is_32 = 1;
128 			argc--;
129 			argv++;
130 		} else if (strcmp(argv[1], "-soft") == 0) {
131 			is_soft = 1;
132 			argc--;
133 			argv++;
134 		} else {
135 			break;
136 		}
137 	}
138 
139 	if (is_soft)
140 		hints_file = _PATH_ELFSOFT_HINTS;	/* Never will have a.out softfloat */
141 	else if (is_32)
142 		hints_file = is_aout ? _PATH_LD32_HINTS : _PATH_ELF32_HINTS;
143 	else
144 		hints_file = is_aout ? _PATH_LD_HINTS : _PATH_ELF_HINTS;
145 	if (argc == 1)
146 		rescan = 1;
147 	else while((c = getopt(argc, argv, "Rf:imrsv")) != -1) {
148 		switch (c) {
149 		case 'R':
150 			rescan = 1;
151 			break;
152 		case 'f':
153 			hints_file = optarg;
154 			break;
155 		case 'i':
156 			insecure = 1;
157 			break;
158 		case 'm':
159 			merge = 1;
160 			break;
161 		case 'r':
162 			justread = 1;
163 			break;
164 		case 's':
165 			nostd = 1;
166 			break;
167 		case 'v':
168 			verbose = 1;
169 			break;
170 		default:
171 			usage();
172 			break;
173 		}
174 	}
175 
176 	if (!is_aout) {
177 		if (justread)
178 			list_elf_hints(hints_file);
179 		else
180 			update_elf_hints(hints_file, argc - optind,
181 			    argv + optind, merge || rescan);
182 		return 0;
183 	}
184 
185 	/* Here begins the aout libs processing */
186 	dir_list = strdup("");
187 
188 	if (justread || merge || rescan) {
189 		if ((rval = readhints()) != 0)
190 			return rval;
191 	}
192 
193 	if (!nostd && !merge && !rescan)
194 		std_search_path();
195 
196 	/* Add any directories/files from the command line */
197 	if (!justread) {
198 		for (i = optind; i < argc; i++) {
199 			struct stat stbuf;
200 
201 			if (stat(argv[i], &stbuf) == -1) {
202 				warn("%s", argv[i]);
203 				rval = -1;
204 			} else if (strcmp(argv[i], "/usr/lib") == 0) {
205 				warnx("WARNING! '%s' can not be used", argv[i]);
206 				rval = -1;
207 			} else {
208 				/*
209 				 * See if this is a directory-containing
210 				 * file instead of a directory
211 				 */
212 				if (S_ISREG(stbuf.st_mode))
213 					rval |= dofile(argv[i], 0);
214 				else
215 					add_search_path(argv[i]);
216 			}
217 		}
218 	}
219 
220 	for (i = 0; i < n_search_dirs; i++) {
221 		char *cp = concat(dir_list, *dir_list?":":"", search_dirs[i]);
222 		free(dir_list);
223 		dir_list = cp;
224 	}
225 
226 	if (justread) {
227 		listhints();
228 		return 0;
229 	}
230 
231 	for (i = 0; i < n_search_dirs; i++)
232 		rval |= dodir(search_dirs[i], 1);
233 
234 	rval |= buildhints();
235 
236 	return rval;
237 }
238 
239 static void
240 usage(void)
241 {
242 	fprintf(stderr,
243 	"usage: ldconfig [-32] [-aout | -elf] [-Rimrsv] [-f hints_file] [directory | file ...]\n");
244 	exit(1);
245 }
246 
247 int
248 dofile(char *fname, int silent)
249 {
250 	FILE *hfp;
251 	char buf[MAXPATHLEN];
252 	int rval = 0;
253 	char *cp, *sp;
254 
255 	if ((hfp = fopen(fname, "r")) == NULL) {
256 		warn("%s", fname);
257 		return -1;
258 	}
259 
260 	while (fgets(buf, sizeof(buf), hfp)) {
261 		cp = buf;
262 		while (isspace(*cp))
263 			cp++;
264 		if (*cp == '#' || *cp == '\0')
265 			continue;
266 		sp = cp;
267 		while (!isspace(*cp) && *cp != '\0')
268 			cp++;
269 
270 		if (*cp != '\n') {
271 			*cp = '\0';
272 			warnx("%s: trailing characters ignored", sp);
273 		}
274 
275 		*cp = '\0';
276 
277 		rval |= dodir(sp, silent);
278 	}
279 
280 	(void)fclose(hfp);
281 	return rval;
282 }
283 
284 int
285 dodir(char *dir, int silent)
286 {
287 	DIR		*dd;
288 	struct dirent	*dp;
289 	char		name[MAXPATHLEN];
290 	int		dewey[MAXDEWEY], ndewey;
291 
292 	if ((dd = opendir(dir)) == NULL) {
293 		if (silent && errno == ENOENT)	/* Ignore the error */
294 			return 0;
295 		warn("%s", dir);
296 		return -1;
297 	}
298 
299 	while ((dp = readdir(dd)) != NULL) {
300 		int n;
301 		char *cp;
302 
303 		/* Check for `lib' prefix */
304 		if (dp->d_name[0] != 'l' ||
305 		    dp->d_name[1] != 'i' ||
306 		    dp->d_name[2] != 'b')
307 			continue;
308 
309 		/* Copy the entry minus prefix */
310 		(void)strcpy(name, dp->d_name + 3);
311 		n = strlen(name);
312 		if (n < 4)
313 			continue;
314 
315 		/* Find ".so." in name */
316 		for (cp = name + n - 4; cp > name; --cp) {
317 			if (cp[0] == '.' &&
318 			    cp[1] == 's' &&
319 			    cp[2] == 'o' &&
320 			    cp[3] == '.')
321 				break;
322 		}
323 		if (cp <= name)
324 			continue;
325 
326 		*cp = '\0';
327 		if (!isdigit(*(cp+4)))
328 			continue;
329 
330 		bzero((caddr_t)dewey, sizeof(dewey));
331 		ndewey = getdewey(dewey, cp + 4);
332 		if (ndewey < 2)
333 			continue;
334 		enter(dir, dp->d_name, name, dewey, ndewey);
335 	}
336 
337 	closedir(dd);
338 	return 0;
339 }
340 
341 static void
342 enter(char *dir, char *file, char *name, int dewey[], int ndewey)
343 {
344 	struct shlib_list	*shp;
345 
346 	for (shp = shlib_head; shp; shp = shp->next) {
347 		if (strcmp(name, shp->name) != 0 || major != shp->major)
348 			continue;
349 
350 		/* Name matches existing entry */
351 		if (cmpndewey(dewey, ndewey, shp->dewey, shp->ndewey) > 0) {
352 
353 			/* Update this entry with higher versioned lib */
354 			if (verbose)
355 				printf("Updating lib%s.%d.%d to %s/%s\n",
356 					shp->name, shp->major, shp->minor,
357 					dir, file);
358 
359 			free(shp->name);
360 			shp->name = strdup(name);
361 			free(shp->path);
362 			shp->path = concat(dir, "/", file);
363 			bcopy(dewey, shp->dewey, sizeof(shp->dewey));
364 			shp->ndewey = ndewey;
365 		}
366 		break;
367 	}
368 
369 	if (shp)
370 		/* Name exists: older version or just updated */
371 		return;
372 
373 	/* Allocate new list element */
374 	if (verbose)
375 		printf("Adding %s/%s\n", dir, file);
376 
377 	shp = (struct shlib_list *)xmalloc(sizeof *shp);
378 	shp->name = strdup(name);
379 	shp->path = concat(dir, "/", file);
380 	bcopy(dewey, shp->dewey, sizeof(shp->dewey));
381 	shp->ndewey = ndewey;
382 	shp->next = NULL;
383 
384 	*shlib_tail = shp;
385 	shlib_tail = &shp->next;
386 }
387 
388 
389 static int
390 hinthash(char *cp, int vmajor)
391 {
392 	int	k = 0;
393 
394 	while (*cp)
395 		k = (((k << 1) + (k >> 14)) ^ (*cp++)) & 0x3fff;
396 
397 	k = (((k << 1) + (k >> 14)) ^ (vmajor*257)) & 0x3fff;
398 
399 	return k;
400 }
401 
402 int
403 buildhints(void)
404 {
405 	struct hints_header	hdr;
406 	struct hints_bucket	*blist;
407 	struct shlib_list	*shp;
408 	char			*strtab;
409 	int			i, n, str_index = 0;
410 	int			strtab_sz = 0;	/* Total length of strings */
411 	int			nhints = 0;	/* Total number of hints */
412 	int			fd;
413 	char			*tmpfilename;
414 
415 	for (shp = shlib_head; shp; shp = shp->next) {
416 		strtab_sz += 1 + strlen(shp->name);
417 		strtab_sz += 1 + strlen(shp->path);
418 		nhints++;
419 	}
420 
421 	/* Fill hints file header */
422 	hdr.hh_magic = HH_MAGIC;
423 	hdr.hh_version = LD_HINTS_VERSION_2;
424 	hdr.hh_nbucket = 1 * nhints;
425 	n = hdr.hh_nbucket * sizeof(struct hints_bucket);
426 	hdr.hh_hashtab = sizeof(struct hints_header);
427 	hdr.hh_strtab = hdr.hh_hashtab + n;
428 	hdr.hh_dirlist = strtab_sz;
429 	strtab_sz += 1 + strlen(dir_list);
430 	hdr.hh_strtab_sz = strtab_sz;
431 	hdr.hh_ehints = hdr.hh_strtab + hdr.hh_strtab_sz;
432 
433 	if (verbose)
434 		printf("Totals: entries %d, buckets %ld, string size %d\n",
435 			nhints, (long)hdr.hh_nbucket, strtab_sz);
436 
437 	/* Allocate buckets and string table */
438 	blist = (struct hints_bucket *)xmalloc(n);
439 	bzero((char *)blist, n);
440 	for (i = 0; i < hdr.hh_nbucket; i++)
441 		/* Empty all buckets */
442 		blist[i].hi_next = -1;
443 
444 	strtab = (char *)xmalloc(strtab_sz);
445 
446 	/* Enter all */
447 	for (shp = shlib_head; shp; shp = shp->next) {
448 		struct hints_bucket	*bp;
449 
450 		bp = blist +
451 		  (hinthash(shp->name, shp->major) % hdr.hh_nbucket);
452 
453 		if (bp->hi_pathx) {
454 			int	j;
455 
456 			for (j = 0; j < hdr.hh_nbucket; j++) {
457 				if (blist[j].hi_pathx == 0)
458 					break;
459 			}
460 			if (j == hdr.hh_nbucket) {
461 				warnx("bummer!");
462 				return -1;
463 			}
464 			while (bp->hi_next != -1)
465 				bp = &blist[bp->hi_next];
466 			bp->hi_next = j;
467 			bp = blist + j;
468 		}
469 
470 		/* Insert strings in string table */
471 		bp->hi_namex = str_index;
472 		strcpy(strtab + str_index, shp->name);
473 		str_index += 1 + strlen(shp->name);
474 
475 		bp->hi_pathx = str_index;
476 		strcpy(strtab + str_index, shp->path);
477 		str_index += 1 + strlen(shp->path);
478 
479 		/* Copy versions */
480 		bcopy(shp->dewey, bp->hi_dewey, sizeof(bp->hi_dewey));
481 		bp->hi_ndewey = shp->ndewey;
482 	}
483 
484 	/* Copy search directories */
485 	strcpy(strtab + str_index, dir_list);
486 	str_index += 1 + strlen(dir_list);
487 
488 	/* Sanity check */
489 	if (str_index != strtab_sz) {
490 		errx(1, "str_index(%d) != strtab_sz(%d)", str_index, strtab_sz);
491 	}
492 
493 	tmpfilename = concat(hints_file, ".XXXXXXXXXX", "");
494 	umask(0);	/* Create with exact permissions */
495 	if ((fd = mkstemp(tmpfilename)) == -1) {
496 		warn("%s", tmpfilename);
497 		return -1;
498 	}
499 	fchmod(fd, 0444);
500 
501 	if (write(fd, &hdr, sizeof(struct hints_header)) !=
502 						sizeof(struct hints_header)) {
503 		warn("%s", hints_file);
504 		return -1;
505 	}
506 	if (write(fd, blist, hdr.hh_nbucket * sizeof(*blist)) !=
507 				(ssize_t)(hdr.hh_nbucket * sizeof(*blist))) {
508 		warn("%s", hints_file);
509 		return -1;
510 	}
511 	if (write(fd, strtab, strtab_sz) != strtab_sz) {
512 		warn("%s", hints_file);
513 		return -1;
514 	}
515 	if (close(fd) != 0) {
516 		warn("%s", hints_file);
517 		return -1;
518 	}
519 
520 	/* Install it */
521 	if (unlink(hints_file) != 0 && errno != ENOENT) {
522 		warn("%s", hints_file);
523 		return -1;
524 	}
525 
526 	if (rename(tmpfilename, hints_file) != 0) {
527 		warn("%s", hints_file);
528 		return -1;
529 	}
530 
531 	return 0;
532 }
533 
534 static int
535 readhints(void)
536 {
537 	int			fd;
538 	void			*addr;
539 	long			fsize;
540 	long			msize;
541 	struct hints_header	*hdr;
542 	struct hints_bucket	*blist;
543 	char			*strtab;
544 	struct shlib_list	*shp;
545 	int			i;
546 
547 	if ((fd = open(hints_file, O_RDONLY, 0)) == -1) {
548 		warn("%s", hints_file);
549 		return -1;
550 	}
551 
552 	msize = PAGE_SIZE;
553 	addr = mmap(0, msize, PROT_READ, MAP_COPY, fd, 0);
554 
555 	if (addr == MAP_FAILED) {
556 		warn("%s", hints_file);
557 		return -1;
558 	}
559 
560 	hdr = (struct hints_header *)addr;
561 	if (HH_BADMAG(*hdr)) {
562 		warnx("%s: bad magic: %lo", hints_file,
563 			(unsigned long)hdr->hh_magic);
564 		return -1;
565 	}
566 
567 	if (hdr->hh_version != LD_HINTS_VERSION_1 &&
568 	    hdr->hh_version != LD_HINTS_VERSION_2) {
569 		warnx("unsupported version: %ld", (long)hdr->hh_version);
570 		return -1;
571 	}
572 
573 	if (hdr->hh_ehints > msize) {
574 		fsize = hdr->hh_ehints;
575 		munmap(addr, msize);
576 		addr = mmap(0, fsize, PROT_READ, MAP_COPY, fd, 0);
577 		if (addr == MAP_FAILED) {
578 			warn("%s", hints_file);
579 			return -1;
580 		}
581 		hdr = (struct hints_header *)addr;
582 	}
583 	close(fd);
584 
585 	strtab = (char *)addr + hdr->hh_strtab;
586 
587 	if (hdr->hh_version >= LD_HINTS_VERSION_2)
588 		add_search_path(strtab + hdr->hh_dirlist);
589 	else if (rescan)
590 		errx(1, "%s too old and does not contain the search path",
591 			hints_file);
592 
593 	if (rescan)
594 		return 0;
595 
596 	blist = malloc(sizeof(*blist) * hdr->hh_nbucket);
597 	if (blist == NULL)
598 		err(1, "readhints");
599 	memcpy(blist, (char *)addr + hdr->hh_hashtab,
600 		sizeof(*blist) * hdr->hh_nbucket);
601 
602 
603 	for (i = 0; i < hdr->hh_nbucket; i++) {
604 		struct hints_bucket	*bp = &blist[i];
605 
606 		/* Sanity check */
607 		if (bp->hi_namex >= hdr->hh_strtab_sz) {
608 			warnx("bad name index: %#x", bp->hi_namex);
609 			free(blist);
610 			return -1;
611 		}
612 		if (bp->hi_pathx >= hdr->hh_strtab_sz) {
613 			warnx("bad path index: %#x", bp->hi_pathx);
614 			free(blist);
615 			return -1;
616 		}
617 
618 		/* Allocate new list element */
619 		shp = (struct shlib_list *)xmalloc(sizeof *shp);
620 		shp->name = strdup(strtab + bp->hi_namex);
621 		shp->path = strdup(strtab + bp->hi_pathx);
622 		bcopy(bp->hi_dewey, shp->dewey, sizeof(shp->dewey));
623 		shp->ndewey = bp->hi_ndewey;
624 		shp->next = NULL;
625 
626 		*shlib_tail = shp;
627 		shlib_tail = &shp->next;
628 	}
629 
630 	free(blist);
631 	return 0;
632 }
633 
634 static void
635 listhints(void)
636 {
637 	struct shlib_list	*shp;
638 	int			i;
639 
640 	printf("%s:\n", hints_file);
641 	printf("\tsearch directories: %s\n", dir_list);
642 
643 	for (i = 0, shp = shlib_head; shp; i++, shp = shp->next)
644 		printf("\t%d:-l%s.%d.%d => %s\n",
645 			i, shp->name, shp->major, shp->minor, shp->path);
646 
647 	return;
648 }
649