xref: /titanic_41/usr/src/cmd/sgs/rtld/common/cap.c (revision f808c858fa61e7769218966759510a8b1190dfcf)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include	"_synonyms.h"
29 
30 #include	<sys/types.h>
31 #include	<sys/mman.h>
32 #include	<dirent.h>
33 #include	<stdio.h>
34 #include	<string.h>
35 #include	<limits.h>
36 #include	<debug.h>
37 #include	<conv.h>
38 #include	"_rtld.h"
39 #include	"_audit.h"
40 #include	"msg.h"
41 
42 /*
43  * qsort(3c) comparison function.
44  */
45 static int
46 compare(const void *fdesc1, const void *fdesc2)
47 {
48 	ulong_t	hwcap1 = ((Fdesc *)fdesc1)->fd_fmap.fm_hwptr;
49 	ulong_t	hwcap2 = ((Fdesc *)fdesc2)->fd_fmap.fm_hwptr;
50 
51 	if (hwcap1 && (hwcap2 == 0))
52 		return (-1);
53 	if ((hwcap1 == 0) && hwcap2)
54 		return (1);
55 	if ((hwcap1 == 0) && (hwcap2 == 0))
56 		return (0);
57 
58 	if (hwcap1 > hwcap2)
59 		return (-1);
60 	if (hwcap1 < hwcap2)
61 		return (1);
62 	return (0);
63 }
64 
65 /*
66  * If this object defines a set of hardware capability requirements, insure the
67  * kernal can cope with them.
68  */
69 int
70 hwcap_check(Rej_desc *rej, Ehdr *ehdr)
71 {
72 	Cap	*cptr;
73 	Phdr	*phdr;
74 	int	cnt;
75 
76 	/* LINTED */
77 	phdr = (Phdr *)((char *)ehdr + ehdr->e_phoff);
78 	for (cnt = 0; cnt < ehdr->e_phnum; cnt++, phdr++) {
79 		Lword	val;
80 
81 		if (phdr->p_type != PT_SUNWCAP)
82 			continue;
83 
84 		/* LINTED */
85 		cptr = (Cap *)((char *)ehdr + phdr->p_offset);
86 		while (cptr->c_tag != CA_SUNW_NULL) {
87 			if (cptr->c_tag == CA_SUNW_HW_1)
88 				break;
89 			cptr++;
90 		}
91 		if (cptr->c_tag == CA_SUNW_NULL)
92 			break;
93 
94 		if ((val = (cptr->c_un.c_val & ~hwcap)) != 0) {
95 			rej->rej_type = SGS_REJ_HWCAP_1;
96 			rej->rej_str = conv_cap_val_hw1(val, M_MACH);
97 			return (0);
98 		}
99 
100 		/*
101 		 * Retain this hardware capabilities pointer for possible later
102 		 * inspection should this object be processed as a filtee.
103 		 */
104 		fmap->fm_hwptr = cptr->c_un.c_val;
105 	}
106 	return (1);
107 }
108 
109 static void
110 remove_fdesc(Fdesc *fdp)
111 {
112 #if	defined(MAP_ALIGN)
113 	if (fdp->fd_fmap.fm_maddr &&
114 	    ((fdp->fd_fmap.fm_mflags & MAP_ALIGN) == 0)) {
115 #else
116 	if (fdp->fd_fmap.fm_maddr) {
117 #endif
118 		(void) munmap(fdp->fd_fmap.fm_maddr, fdp->fd_fmap.fm_msize);
119 
120 		/*
121 		 * Note, this file descriptor might be duplicating information
122 		 * from the global fmap descriptor.  If so, clean up the global
123 		 * descriptor to prevent a duplicate (unnecessary) unmap.
124 		 */
125 		if (fmap->fm_maddr == fdp->fd_fmap.fm_maddr)
126 			fmap->fm_maddr = 0;
127 	}
128 	if (fdp->fd_fd)
129 		(void) close(fdp->fd_fd);
130 	if (fdp->fd_pname && (fdp->fd_pname != fdp->fd_nname))
131 		free((void *)fdp->fd_pname);
132 	if (fdp->fd_nname)
133 		free((void *)fdp->fd_nname);
134 }
135 
136 /*
137  * When $HWCAP is used to represent dependencies, take the associated directory
138  * and analyze all the files it contains.
139  */
140 int
141 hwcap_dir(Alist **fdalpp, Lm_list *lml, const char *name, Rt_map *clmp,
142     uint_t flags, Rej_desc *rej)
143 {
144 	char		path[PATH_MAX], *dst;
145 	const char	*src;
146 	DIR		*dir;
147 	struct dirent	*dirent;
148 	Aliste		off;
149 	Alist		*fdalp = 0;
150 	Fdesc		*fdp;
151 	int		error = 0;
152 
153 	/*
154 	 * Access the directory in preparation for reading its entries.  If
155 	 * successful, establish the initial pathname.
156 	 */
157 	if ((dir = opendir(name)) == 0) {
158 		Rej_desc	_rej = { 0 };
159 
160 		_rej.rej_type = SGS_REJ_STR;
161 		_rej.rej_name = name;
162 		_rej.rej_str = strerror(errno);
163 		DBG_CALL(Dbg_file_rejected(lml, &_rej));
164 		rejection_inherit(rej, &_rej, 0);
165 		return (0);
166 	}
167 
168 	for (dst = path, src = name; *src; dst++, src++)
169 		*dst = *src;
170 	*dst++ = '/';
171 
172 	/*
173 	 * Read each entry from the directory and determine whether it is a
174 	 * valid ELF file.
175 	 */
176 	while ((dirent = readdir(dir)) != NULL) {
177 		const char	*file = dirent->d_name;
178 		char		*_dst;
179 		Fdesc		fdesc = { 0 };
180 		Rej_desc	_rej = { 0 };
181 
182 		/*
183 		 * Ignore "." and ".." entries.
184 		 */
185 		if ((file[0] == '.') && ((file[1] == '\0') ||
186 		    ((file[1] == '.') && (file[2] == '\0'))))
187 			continue;
188 
189 		/*
190 		 * Complete the full pathname, and verify its usability.
191 		 */
192 		for (_dst = dst, src = file, file = dst; *src; _dst++, src++)
193 			*_dst = *src;
194 		*_dst = '\0';
195 
196 		if ((name = strdup(path)) == 0) {
197 			error = 1;
198 			break;
199 		}
200 		if ((name = load_trace(lml, name, clmp)) == 0)
201 			continue;
202 
203 		if (find_path(lml, name, clmp, flags, &fdesc, &_rej) == 0)
204 			rejection_inherit(rej, &_rej, &fdesc);
205 		else {
206 			DBG_CALL(Dbg_cap_hw_candidate(lml, name));
207 
208 			/*
209 			 * If this object has already been loaded, obtain the
210 			 * hardware capabilities for later sorting.  Otherwise
211 			 * we have a new candidate.
212 			 */
213 			if (fdesc.fd_lmp)
214 				fdesc.fd_fmap.fm_hwptr = HWCAP(fdesc.fd_lmp);
215 			else
216 				fdesc.fd_fmap = *fmap;
217 
218 			if (alist_append(&fdalp, &fdesc,
219 			    sizeof (Fdesc), 10) == 0) {
220 				remove_fdesc(&fdesc);
221 				error = 1;
222 				break;
223 			}
224 		}
225 
226 		/*
227 		 * Clear the global file mapping structure so that the mapping
228 		 * for this file won't be overriden.
229 		 */
230 		fmap->fm_mflags = MAP_PRIVATE;
231 		fmap->fm_maddr = 0;
232 		fmap->fm_msize = syspagsz;
233 		fmap->fm_hwptr = 0;
234 
235 	}
236 	(void) closedir(dir);
237 
238 	/*
239 	 * If no objects have been found, we're done.  Also, if an allocation
240 	 * error occurred while processing any object, remove any objects that
241 	 * had already been added to the list and return.
242 	 */
243 	if ((fdalp == 0) || error) {
244 		if (fdalp) {
245 			for (ALIST_TRAVERSE(fdalp, off, fdp))
246 				remove_fdesc(fdp);
247 			free(fdalp);
248 		}
249 		return (0);
250 	}
251 
252 	/*
253 	 * Having processed and retained all candidates from this directory,
254 	 * sort them, based on the precedence of their hardware capabilities.
255 	 */
256 	qsort(&(fdalp->al_data[0]), ((fdalp->al_next - (sizeof (Alist) -
257 	    sizeof (void *))) / fdalp->al_size), fdalp->al_size, compare);
258 
259 	*fdalpp = fdalp;
260 	return (1);
261 }
262 
263 static Pnode *
264 _hwcap_filtees(Pnode **pnpp, Aliste nlmco, Rt_map *flmp, const char *ref,
265     const char *dir, int mode, uint_t flags)
266 {
267 	Alist		*fdalp = 0;
268 	Aliste		off;
269 	Pnode		*fpnp = 0, *lpnp, *npnp = (*pnpp)->p_next;
270 	Fdesc		*fdp;
271 	Lm_list		*lml = LIST(flmp);
272 	int		unused = 0;
273 	Rej_desc	rej = { 0 };
274 
275 	if (hwcap_dir(&fdalp, lml, dir, flmp, flags, &rej) == 0) {
276 		remove_rej(&rej);
277 		return (0);
278 	}
279 
280 	/*
281 	 * Now complete the mapping of each of the ordered objects, adding
282 	 * each object to a new Pnode.
283 	 */
284 	for (ALIST_TRAVERSE(fdalp, off, fdp)) {
285 		Rt_map	*nlmp;
286 		Grp_hdl	*ghp = 0;
287 		Pnode	*pnp;
288 		int	audit = 0;
289 
290 		if (unused) {
291 			/*
292 			 * Flush out objects remaining.
293 			 */
294 			remove_fdesc(fdp);
295 			continue;
296 		}
297 
298 		/*
299 		 * Complete mapping the file, obtaining a handle, and continue
300 		 * to analyze the object, establishing dependencies and
301 		 * relocating.  Remove the file descriptor at this point, as it
302 		 * is no longer required.
303 		 */
304 		DBG_CALL(Dbg_file_filtee(lml, NAME(flmp), fdp->fd_nname, 0));
305 
306 		nlmp = load_path(lml, nlmco, fdp->fd_nname, flmp, mode,
307 		    (flags | FLG_RT_HANDLE), &ghp, fdp, &rej);
308 		remove_fdesc(fdp);
309 
310 		/*
311 		 * Create a new Pnode to represent this filtee, and substitute
312 		 * the calling Pnode (which was used to represent the hardware
313 		 * capability directory).
314 		 */
315 		if ((pnp = calloc(1, sizeof (Pnode))) == 0) {
316 			if (ghp)
317 				(void) dlclose_core(ghp, flmp);
318 			return (0);
319 		}
320 		if ((pnp->p_name = strdup(NAME(nlmp))) == 0) {
321 			if (ghp)
322 				(void) dlclose_core(ghp, flmp);
323 			free(pnp);
324 			return (0);
325 		}
326 		pnp->p_len = strlen(NAME(nlmp));
327 		pnp->p_info = (void *)ghp;
328 		pnp->p_next = npnp;
329 
330 		if (fpnp == 0) {
331 			Pnode	*opnp = (*pnpp);
332 
333 			/*
334 			 * If this is the first pnode, reuse the original after
335 			 * freeing any of its pathnames.
336 			 */
337 			if (opnp->p_name)
338 				free((void *)opnp->p_name);
339 			if (opnp->p_oname)
340 				free((void *)opnp->p_oname);
341 			*opnp = *pnp;
342 			free((void *)pnp);
343 			fpnp = lpnp = pnp = opnp;
344 		} else {
345 			lpnp->p_next = pnp;
346 			lpnp = pnp;
347 		}
348 
349 		/*
350 		 * Establish the filter handle to prevent any recursion.
351 		 */
352 		if (nlmp && ghp) {
353 			ghp->gh_flags |= GPH_FILTEE;
354 			pnp->p_info = (void *)ghp;
355 		}
356 
357 		/*
358 		 * Audit the filter/filtee established.  A return of 0
359 		 * indicates the auditor wishes to ignore this filtee.
360 		 */
361 		if (nlmp && (lml->lm_tflags | FLAGS1(flmp)) &
362 		    LML_TFLG_AUD_OBJFILTER) {
363 			if (audit_objfilter(flmp, ref, nlmp, 0) == 0) {
364 				audit = 1;
365 				nlmp = 0;
366 			}
367 		}
368 
369 		/*
370 		 * Finish processing the objects associated with this request.
371 		 */
372 		if (nlmp && ghp && ((analyze_lmc(lml, nlmco, nlmp) == 0) ||
373 		    (relocate_lmc(lml, nlmco, nlmp) == 0)))
374 			nlmp = 0;
375 
376 		/*
377 		 * Finally, if the filtee is part of a link-map control list
378 		 * that is equivalent, or less, than the filter control list,
379 		 * create an association between the filter and filtee.  This
380 		 * association provides sufficient information to tear down the
381 		 * filter and filtee if necessary.
382 		 */
383 		if (nlmp && ghp && (CNTL(nlmp) <= CNTL(flmp)) &&
384 		    (hdl_add(ghp, flmp, GPD_FILTER) == 0))
385 			nlmp = 0;
386 
387 		/*
388 		 * If this object is marked an end-filtee, we're done.
389 		 */
390 		if (nlmp && ghp && (FLAGS1(nlmp) & FL1_RT_ENDFILTE))
391 			unused = 1;
392 
393 		/*
394 		 * Generate a diagnostic if the filtee couldn't be loaded, null
395 		 * out the pnode entry, and continue the search.
396 		 */
397 		if (nlmp == 0) {
398 			pnp->p_info = 0;
399 			DBG_CALL(Dbg_file_filtee(lml, 0, pnp->p_name, audit));
400 			if (ghp)
401 				(void) dlclose_core(ghp, flmp);
402 
403 			pnp->p_len = 0;
404 		}
405 	}
406 
407 	free(fdalp);
408 	return (fpnp);
409 }
410 
411 Pnode *
412 hwcap_filtees(Pnode **pnpp, Aliste nlmco, Dyninfo *dip, Rt_map *flmp,
413     const char *ref, int mode, uint_t flags)
414 {
415 	Pnode		*pnp = *pnpp;
416 	const char	*dir = pnp->p_name;
417 	Lm_list		*flml = LIST(flmp);
418 
419 	DBG_CALL(Dbg_cap_hw_filter(flml, dir, flmp));
420 
421 	if ((pnp = _hwcap_filtees(pnpp, nlmco, flmp, ref, dir, mode,
422 	    flags)) != 0)
423 		return (pnp);
424 
425 	/*
426 	 * If no hardware capability filtees have been found, provide suitable
427 	 * diagnostics and mark the incoming Pnode as unused.
428 	 */
429 	if ((flml->lm_flags & LML_FLG_TRC_ENABLE) &&
430 	    (dip->di_flags & FLG_DI_AUXFLTR) && (rtld_flags & RT_FL_WARNFLTR))
431 		(void) printf(MSG_INTL(MSG_LDD_HWCAP_NFOUND), dir);
432 
433 	DBG_CALL(Dbg_cap_hw_filter(flml, dir, 0));
434 
435 	pnp = *pnpp;
436 	pnp->p_len = 0;
437 	return (pnp);
438 }
439 
440 /*
441  * Load an individual hardware capabilities object.
442  */
443 Rt_map *
444 load_hwcap(Lm_list *lml, Aliste lmco, const char *dir, Rt_map *clmp,
445     uint_t mode, uint_t flags, Grp_hdl **hdl, Rej_desc *rej)
446 {
447 	Alist		*fdalp = 0;
448 	Aliste		off;
449 	Fdesc		*fdp;
450 	int		found = 0;
451 	Rt_map		*lmp = 0;
452 
453 	/*
454 	 * Obtain the sorted list of hardware capabilites objects available.
455 	 */
456 	if (hwcap_dir(&fdalp, lml, dir, clmp, flags, rej) == 0)
457 		return (0);
458 
459 	/*
460 	 * From the list of hardware capability objects, use the first and
461 	 * discard the rest.
462 	 */
463 	for (ALIST_TRAVERSE(fdalp, off, fdp)) {
464 		if ((found == 0) && ((lmp = load_path(lml, lmco, fdp->fd_nname,
465 		    clmp, mode, flags, hdl, fdp, rej)) != 0))
466 			found++;
467 
468 		/*
469 		 * Remove the used file descriptor and any objects remaining.
470 		 */
471 		remove_fdesc(fdp);
472 	}
473 
474 	free(fdalp);
475 	return (lmp);
476 }
477