xref: /netbsd-src/external/cddl/osnet/dist/lib/libdtrace/common/dt_module.c (revision ad49149131b7552cf1c4fc41370cc055d9b4a80e)
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 (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 /*
26  * Copyright (c) 2013, Joyent, Inc.  All rights reserved.
27  * Copyright (c) 2016, Pedro Giffuni.  All rights reserved.
28  */
29 
30 #include <sys/types.h>
31 #ifdef illumos
32 #include <sys/modctl.h>
33 #include <sys/kobj.h>
34 #include <sys/kobj_impl.h>
35 #include <sys/sysmacros.h>
36 #include <sys/elf.h>
37 #include <sys/task.h>
38 #else
39 #include <sys/param.h>
40 //#include <sys/linker.h>
41 #include <sys/module.h>
42 #include <sys/stat.h>
43 #endif
44 #ifdef __NetBSD__
45 #include <sys/sysctl.h>
46 #include <paths.h>
47 #endif
48 
49 #include <unistd.h>
50 #ifdef illumos
51 #include <project.h>
52 #endif
53 #include <strings.h>
54 #include <stdlib.h>
55 #include <libelf.h>
56 #include <limits.h>
57 #include <assert.h>
58 #include <errno.h>
59 #include <dirent.h>
60 #ifndef illumos
61 #include <fcntl.h>
62 #include <libproc_compat.h>
63 #endif
64 
65 #include <dt_strtab.h>
66 #include <dt_module.h>
67 #include <dt_impl.h>
68 
69 static const char *dt_module_strtab; /* active strtab for qsort callbacks */
70 
71 static void
dt_module_symhash_insert(dt_module_t * dmp,const char * name,uint_t id)72 dt_module_symhash_insert(dt_module_t *dmp, const char *name, uint_t id)
73 {
74 	dt_sym_t *dsp = &dmp->dm_symchains[dmp->dm_symfree];
75 	uint_t h;
76 
77 	assert(dmp->dm_symfree < dmp->dm_nsymelems + 1);
78 
79 	dsp->ds_symid = id;
80 	h = dt_strtab_hash(name, NULL) % dmp->dm_nsymbuckets;
81 	dsp->ds_next = dmp->dm_symbuckets[h];
82 	dmp->dm_symbuckets[h] = dmp->dm_symfree++;
83 }
84 
85 static uint_t
dt_module_syminit32(dt_module_t * dmp)86 dt_module_syminit32(dt_module_t *dmp)
87 {
88 #if STT_NUM != (STT_TLS + 1)
89 #error "STT_NUM has grown. update dt_module_syminit32()"
90 #endif
91 
92 	Elf32_Sym *sym = dmp->dm_symtab.cts_data;
93 	const char *base = dmp->dm_strtab.cts_data;
94 	size_t ss_size = dmp->dm_strtab.cts_size;
95 	uint_t i, n = dmp->dm_nsymelems;
96 	uint_t asrsv = 0;
97 
98 #if defined(__FreeBSD__)
99 	GElf_Ehdr ehdr;
100 	int is_elf_obj;
101 
102 	gelf_getehdr(dmp->dm_elf, &ehdr);
103 	is_elf_obj = (ehdr.e_type == ET_REL);
104 #endif
105 
106 	for (i = 0; i < n; i++, sym++) {
107 		const char *name = base + sym->st_name;
108 		uchar_t type = ELF32_ST_TYPE(sym->st_info);
109 
110 		if (type >= STT_NUM || type == STT_SECTION)
111 			continue; /* skip sections and unknown types */
112 
113 		if (sym->st_name == 0 || sym->st_name >= ss_size)
114 			continue; /* skip null or invalid names */
115 
116 		if (sym->st_value != 0 &&
117 		    (ELF32_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size)) {
118 			asrsv++; /* reserve space in the address map */
119 
120 #if defined(__FreeBSD__)
121 			sym->st_value += (Elf_Addr) dmp->dm_reloc_offset;
122 			if (is_elf_obj && sym->st_shndx != SHN_UNDEF &&
123 			    sym->st_shndx < ehdr.e_shnum)
124 				sym->st_value +=
125 				    dmp->dm_sec_offsets[sym->st_shndx];
126 #endif
127 #ifdef __NetBSD__
128 			sym->st_value += (uintptr_t) dmp->dm_reloc_offset;
129 #endif
130 		}
131 
132 		dt_module_symhash_insert(dmp, name, i);
133 	}
134 
135 	return (asrsv);
136 }
137 
138 static uint_t
dt_module_syminit64(dt_module_t * dmp)139 dt_module_syminit64(dt_module_t *dmp)
140 {
141 #if STT_NUM != (STT_TLS + 1)
142 #error "STT_NUM has grown. update dt_module_syminit64()"
143 #endif
144 
145 	Elf64_Sym *sym = dmp->dm_symtab.cts_data;
146 	const char *base = dmp->dm_strtab.cts_data;
147 	size_t ss_size = dmp->dm_strtab.cts_size;
148 	uint_t i, n = dmp->dm_nsymelems;
149 	uint_t asrsv = 0;
150 
151 #if defined(__FreeBSD__)
152 	GElf_Ehdr ehdr;
153 	int is_elf_obj;
154 
155 	gelf_getehdr(dmp->dm_elf, &ehdr);
156 	is_elf_obj = (ehdr.e_type == ET_REL);
157 #endif
158 
159 	for (i = 0; i < n; i++, sym++) {
160 		const char *name = base + sym->st_name;
161 		uchar_t type = ELF64_ST_TYPE(sym->st_info);
162 
163 		if (type >= STT_NUM || type == STT_SECTION)
164 			continue; /* skip sections and unknown types */
165 
166 		if (sym->st_name == 0 || sym->st_name >= ss_size)
167 			continue; /* skip null or invalid names */
168 
169 		if (sym->st_value != 0 &&
170 		    (ELF64_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size)) {
171 			asrsv++; /* reserve space in the address map */
172 #if defined(__FreeBSD__)
173 			sym->st_value += (Elf_Addr) dmp->dm_reloc_offset;
174 			if (is_elf_obj && sym->st_shndx != SHN_UNDEF &&
175 			    sym->st_shndx < ehdr.e_shnum)
176 				sym->st_value +=
177 				    dmp->dm_sec_offsets[sym->st_shndx];
178 #endif
179 #ifdef __NetBSD__
180 			sym->st_value += (uintptr_t) dmp->dm_reloc_offset;
181 #endif
182 		}
183 
184 		dt_module_symhash_insert(dmp, name, i);
185 	}
186 
187 	return (asrsv);
188 }
189 
190 /*
191  * Sort comparison function for 32-bit symbol address-to-name lookups.  We sort
192  * symbols by value.  If values are equal, we prefer the symbol that is
193  * non-zero sized, typed, not weak, or lexically first, in that order.
194  */
195 static int
dt_module_symcomp32(const void * lp,const void * rp)196 dt_module_symcomp32(const void *lp, const void *rp)
197 {
198 	Elf32_Sym *lhs = *((Elf32_Sym **)lp);
199 	Elf32_Sym *rhs = *((Elf32_Sym **)rp);
200 
201 	if (lhs->st_value != rhs->st_value)
202 		return (lhs->st_value > rhs->st_value ? 1 : -1);
203 
204 	if ((lhs->st_size == 0) != (rhs->st_size == 0))
205 		return (lhs->st_size == 0 ? 1 : -1);
206 
207 	if ((ELF32_ST_TYPE(lhs->st_info) == STT_NOTYPE) !=
208 	    (ELF32_ST_TYPE(rhs->st_info) == STT_NOTYPE))
209 		return (ELF32_ST_TYPE(lhs->st_info) == STT_NOTYPE ? 1 : -1);
210 
211 	if ((ELF32_ST_BIND(lhs->st_info) == STB_WEAK) !=
212 	    (ELF32_ST_BIND(rhs->st_info) == STB_WEAK))
213 		return (ELF32_ST_BIND(lhs->st_info) == STB_WEAK ? 1 : -1);
214 
215 	return (strcmp(dt_module_strtab + lhs->st_name,
216 	    dt_module_strtab + rhs->st_name));
217 }
218 
219 /*
220  * Sort comparison function for 64-bit symbol address-to-name lookups.  We sort
221  * symbols by value.  If values are equal, we prefer the symbol that is
222  * non-zero sized, typed, not weak, or lexically first, in that order.
223  */
224 static int
dt_module_symcomp64(const void * lp,const void * rp)225 dt_module_symcomp64(const void *lp, const void *rp)
226 {
227 	Elf64_Sym *lhs = *((Elf64_Sym **)lp);
228 	Elf64_Sym *rhs = *((Elf64_Sym **)rp);
229 
230 	if (lhs->st_value != rhs->st_value)
231 		return (lhs->st_value > rhs->st_value ? 1 : -1);
232 
233 	if ((lhs->st_size == 0) != (rhs->st_size == 0))
234 		return (lhs->st_size == 0 ? 1 : -1);
235 
236 	if ((ELF64_ST_TYPE(lhs->st_info) == STT_NOTYPE) !=
237 	    (ELF64_ST_TYPE(rhs->st_info) == STT_NOTYPE))
238 		return (ELF64_ST_TYPE(lhs->st_info) == STT_NOTYPE ? 1 : -1);
239 
240 	if ((ELF64_ST_BIND(lhs->st_info) == STB_WEAK) !=
241 	    (ELF64_ST_BIND(rhs->st_info) == STB_WEAK))
242 		return (ELF64_ST_BIND(lhs->st_info) == STB_WEAK ? 1 : -1);
243 
244 	return (strcmp(dt_module_strtab + lhs->st_name,
245 	    dt_module_strtab + rhs->st_name));
246 }
247 
248 static void
dt_module_symsort32(dt_module_t * dmp)249 dt_module_symsort32(dt_module_t *dmp)
250 {
251 	Elf32_Sym *symtab = (Elf32_Sym *)dmp->dm_symtab.cts_data;
252 	Elf32_Sym **sympp = (Elf32_Sym **)dmp->dm_asmap;
253 	const dt_sym_t *dsp = dmp->dm_symchains + 1;
254 	uint_t i, n = dmp->dm_symfree;
255 
256 	for (i = 1; i < n; i++, dsp++) {
257 		Elf32_Sym *sym = symtab + dsp->ds_symid;
258 		if (sym->st_value != 0 &&
259 		    (ELF32_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size))
260 			*sympp++ = sym;
261 	}
262 
263 	dmp->dm_aslen = (uint_t)(sympp - (Elf32_Sym **)dmp->dm_asmap);
264 	assert(dmp->dm_aslen <= dmp->dm_asrsv);
265 
266 	dt_module_strtab = dmp->dm_strtab.cts_data;
267 	qsort(dmp->dm_asmap, dmp->dm_aslen,
268 	    sizeof (Elf32_Sym *), dt_module_symcomp32);
269 	dt_module_strtab = NULL;
270 }
271 
272 static void
dt_module_symsort64(dt_module_t * dmp)273 dt_module_symsort64(dt_module_t *dmp)
274 {
275 	Elf64_Sym *symtab = (Elf64_Sym *)dmp->dm_symtab.cts_data;
276 	Elf64_Sym **sympp = (Elf64_Sym **)dmp->dm_asmap;
277 	const dt_sym_t *dsp = dmp->dm_symchains + 1;
278 	uint_t i, n = dmp->dm_symfree;
279 
280 	for (i = 1; i < n; i++, dsp++) {
281 		Elf64_Sym *sym = symtab + dsp->ds_symid;
282 		if (sym->st_value != 0 &&
283 		    (ELF64_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size))
284 			*sympp++ = sym;
285 	}
286 
287 	dmp->dm_aslen = (uint_t)(sympp - (Elf64_Sym **)dmp->dm_asmap);
288 	assert(dmp->dm_aslen <= dmp->dm_asrsv);
289 
290 	dt_module_strtab = dmp->dm_strtab.cts_data;
291 	qsort(dmp->dm_asmap, dmp->dm_aslen,
292 	    sizeof (Elf64_Sym *), dt_module_symcomp64);
293 	dt_module_strtab = NULL;
294 }
295 
296 static GElf_Sym *
dt_module_symgelf32(const Elf32_Sym * src,GElf_Sym * dst)297 dt_module_symgelf32(const Elf32_Sym *src, GElf_Sym *dst)
298 {
299 	if (dst != NULL) {
300 		dst->st_name = src->st_name;
301 		dst->st_info = src->st_info;
302 		dst->st_other = src->st_other;
303 		dst->st_shndx = src->st_shndx;
304 		dst->st_value = src->st_value;
305 		dst->st_size = src->st_size;
306 	}
307 
308 	return (dst);
309 }
310 
311 static GElf_Sym *
dt_module_symgelf64(const Elf64_Sym * src,GElf_Sym * dst)312 dt_module_symgelf64(const Elf64_Sym *src, GElf_Sym *dst)
313 {
314 	if (dst != NULL)
315 		bcopy(src, dst, sizeof (GElf_Sym));
316 
317 	return (dst);
318 }
319 
320 static GElf_Sym *
dt_module_symname32(dt_module_t * dmp,const char * name,GElf_Sym * symp,uint_t * idp)321 dt_module_symname32(dt_module_t *dmp, const char *name,
322     GElf_Sym *symp, uint_t *idp)
323 {
324 	const Elf32_Sym *symtab = dmp->dm_symtab.cts_data;
325 	const char *strtab = dmp->dm_strtab.cts_data;
326 
327 	const Elf32_Sym *sym;
328 	const dt_sym_t *dsp;
329 	uint_t i, h;
330 
331 	if (dmp->dm_nsymelems == 0)
332 		return (NULL);
333 
334 	h = dt_strtab_hash(name, NULL) % dmp->dm_nsymbuckets;
335 
336 	for (i = dmp->dm_symbuckets[h]; i != 0; i = dsp->ds_next) {
337 		dsp = &dmp->dm_symchains[i];
338 		sym = symtab + dsp->ds_symid;
339 
340 		if (strcmp(name, strtab + sym->st_name) == 0) {
341 			if (idp != NULL)
342 				*idp = dsp->ds_symid;
343 			return (dt_module_symgelf32(sym, symp));
344 		}
345 	}
346 
347 	return (NULL);
348 }
349 
350 static GElf_Sym *
dt_module_symname64(dt_module_t * dmp,const char * name,GElf_Sym * symp,uint_t * idp)351 dt_module_symname64(dt_module_t *dmp, const char *name,
352     GElf_Sym *symp, uint_t *idp)
353 {
354 	const Elf64_Sym *symtab = dmp->dm_symtab.cts_data;
355 	const char *strtab = dmp->dm_strtab.cts_data;
356 
357 	const Elf64_Sym *sym;
358 	const dt_sym_t *dsp;
359 	uint_t i, h;
360 
361 	if (dmp->dm_nsymelems == 0)
362 		return (NULL);
363 
364 	h = dt_strtab_hash(name, NULL) % dmp->dm_nsymbuckets;
365 
366 	for (i = dmp->dm_symbuckets[h]; i != 0; i = dsp->ds_next) {
367 		dsp = &dmp->dm_symchains[i];
368 		sym = symtab + dsp->ds_symid;
369 
370 		if (strcmp(name, strtab + sym->st_name) == 0) {
371 			if (idp != NULL)
372 				*idp = dsp->ds_symid;
373 			return (dt_module_symgelf64(sym, symp));
374 		}
375 	}
376 
377 	return (NULL);
378 }
379 
380 static GElf_Sym *
dt_module_symaddr32(dt_module_t * dmp,GElf_Addr addr,GElf_Sym * symp,uint_t * idp)381 dt_module_symaddr32(dt_module_t *dmp, GElf_Addr addr,
382     GElf_Sym *symp, uint_t *idp)
383 {
384 	const Elf32_Sym **asmap = (const Elf32_Sym **)dmp->dm_asmap;
385 	const Elf32_Sym *symtab = dmp->dm_symtab.cts_data;
386 	const Elf32_Sym *sym;
387 
388 	uint_t i, mid, lo = 0, hi = dmp->dm_aslen - 1;
389 	Elf32_Addr v;
390 
391 	if (dmp->dm_aslen == 0)
392 		return (NULL);
393 
394 	while (hi - lo > 1) {
395 		mid = (lo + hi) / 2;
396 		if (addr >= asmap[mid]->st_value)
397 			lo = mid;
398 		else
399 			hi = mid;
400 	}
401 
402 	i = addr < asmap[hi]->st_value ? lo : hi;
403 	sym = asmap[i];
404 	v = sym->st_value;
405 
406 	/*
407 	 * If the previous entry has the same value, improve our choice.  The
408 	 * order of equal-valued symbols is determined by the comparison func.
409 	 */
410 	while (i-- != 0 && asmap[i]->st_value == v)
411 		sym = asmap[i];
412 
413 	if (addr - sym->st_value < MAX(sym->st_size, 1)) {
414 		if (idp != NULL)
415 			*idp = (uint_t)(sym - symtab);
416 		return (dt_module_symgelf32(sym, symp));
417 	}
418 
419 	return (NULL);
420 }
421 
422 static GElf_Sym *
dt_module_symaddr64(dt_module_t * dmp,GElf_Addr addr,GElf_Sym * symp,uint_t * idp)423 dt_module_symaddr64(dt_module_t *dmp, GElf_Addr addr,
424     GElf_Sym *symp, uint_t *idp)
425 {
426 	const Elf64_Sym **asmap = (const Elf64_Sym **)dmp->dm_asmap;
427 	const Elf64_Sym *symtab = dmp->dm_symtab.cts_data;
428 	const Elf64_Sym *sym;
429 
430 	uint_t i, mid, lo = 0, hi = dmp->dm_aslen - 1;
431 	Elf64_Addr v;
432 
433 	if (dmp->dm_aslen == 0)
434 		return (NULL);
435 
436 	while (hi - lo > 1) {
437 		mid = (lo + hi) / 2;
438 		if (addr >= asmap[mid]->st_value)
439 			lo = mid;
440 		else
441 			hi = mid;
442 	}
443 
444 	i = addr < asmap[hi]->st_value ? lo : hi;
445 	sym = asmap[i];
446 	v = sym->st_value;
447 
448 	/*
449 	 * If the previous entry has the same value, improve our choice.  The
450 	 * order of equal-valued symbols is determined by the comparison func.
451 	 */
452 	while (i-- != 0 && asmap[i]->st_value == v)
453 		sym = asmap[i];
454 
455 	if (addr - sym->st_value < MAX(sym->st_size, 1)) {
456 		if (idp != NULL)
457 			*idp = (uint_t)(sym - symtab);
458 		return (dt_module_symgelf64(sym, symp));
459 	}
460 
461 	return (NULL);
462 }
463 
464 static const dt_modops_t dt_modops_32 = {
465 	dt_module_syminit32,
466 	dt_module_symsort32,
467 	dt_module_symname32,
468 	dt_module_symaddr32
469 };
470 
471 static const dt_modops_t dt_modops_64 = {
472 	dt_module_syminit64,
473 	dt_module_symsort64,
474 	dt_module_symname64,
475 	dt_module_symaddr64
476 };
477 
478 dt_module_t *
dt_module_create(dtrace_hdl_t * dtp,const char * name)479 dt_module_create(dtrace_hdl_t *dtp, const char *name)
480 {
481 	long pid;
482 	char *eptr;
483 	dt_ident_t *idp;
484 	uint_t h = dt_strtab_hash(name, NULL) % dtp->dt_modbuckets;
485 	dt_module_t *dmp;
486 
487 	for (dmp = dtp->dt_mods[h]; dmp != NULL; dmp = dmp->dm_next) {
488 		if (strcmp(dmp->dm_name, name) == 0)
489 			return (dmp);
490 	}
491 
492 	if ((dmp = malloc(sizeof (dt_module_t))) == NULL)
493 		return (NULL); /* caller must handle allocation failure */
494 
495 	bzero(dmp, sizeof (dt_module_t));
496 	(void) strlcpy(dmp->dm_name, name, sizeof (dmp->dm_name));
497 	dt_list_append(&dtp->dt_modlist, dmp);
498 	dmp->dm_next = dtp->dt_mods[h];
499 	dtp->dt_mods[h] = dmp;
500 	dtp->dt_nmods++;
501 
502 	if (dtp->dt_conf.dtc_ctfmodel == CTF_MODEL_LP64)
503 		dmp->dm_ops = &dt_modops_64;
504 	else
505 		dmp->dm_ops = &dt_modops_32;
506 
507 	/*
508 	 * Modules for userland processes are special. They always refer to a
509 	 * specific process and have a copy of their CTF data from a specific
510 	 * instant in time. Any dt_module_t that begins with 'pid' is a module
511 	 * for a specific process, much like how any probe description that
512 	 * begins with 'pid' is special. pid123 refers to process 123. A module
513 	 * that is just 'pid' refers specifically to pid$target. This is
514 	 * generally done as D does not currently allow for macros to be
515 	 * evaluated when working with types.
516 	 */
517 	if (strncmp(dmp->dm_name, "pid", 3) == 0) {
518 		errno = 0;
519 		if (dmp->dm_name[3] == '\0') {
520 			idp = dt_idhash_lookup(dtp->dt_macros, "target");
521 			if (idp != NULL && idp->di_id != 0)
522 				dmp->dm_pid = idp->di_id;
523 		} else {
524 			pid = strtol(dmp->dm_name + 3, &eptr, 10);
525 			if (errno == 0 && *eptr == '\0')
526 				dmp->dm_pid = (pid_t)pid;
527 			else
528 				dt_dprintf("encountered malformed pid "
529 				    "module: %s\n", dmp->dm_name);
530 		}
531 	}
532 
533 	return (dmp);
534 }
535 
536 dt_module_t *
dt_module_lookup_by_name(dtrace_hdl_t * dtp,const char * name)537 dt_module_lookup_by_name(dtrace_hdl_t *dtp, const char *name)
538 {
539 	uint_t h = dt_strtab_hash(name, NULL) % dtp->dt_modbuckets;
540 	dt_module_t *dmp;
541 
542 	for (dmp = dtp->dt_mods[h]; dmp != NULL; dmp = dmp->dm_next) {
543 		if (strcmp(dmp->dm_name, name) == 0)
544 			return (dmp);
545 	}
546 
547 	return (NULL);
548 }
549 
550 /*ARGSUSED*/
551 dt_module_t *
dt_module_lookup_by_ctf(dtrace_hdl_t * dtp,ctf_file_t * ctfp)552 dt_module_lookup_by_ctf(dtrace_hdl_t *dtp, ctf_file_t *ctfp)
553 {
554 	return (ctfp ? ctf_getspecific(ctfp) : NULL);
555 }
556 
557 #if defined(__FreeBSD__) || defined(__NetBSD__)
558 dt_kmodule_t *
dt_kmodule_lookup(dtrace_hdl_t * dtp,const char * name)559 dt_kmodule_lookup(dtrace_hdl_t *dtp, const char *name)
560 {
561 	uint_t h = dt_strtab_hash(name, NULL) % dtp->dt_modbuckets;
562 	dt_kmodule_t *dkmp;
563 
564 	for (dkmp = dtp->dt_kmods[h]; dkmp != NULL; dkmp = dkmp->dkm_next) {
565 		if (strcmp(dkmp->dkm_name, name) == 0)
566 			return (dkmp);
567 	}
568 
569 	return (NULL);
570 }
571 #endif
572 
573 static int
dt_module_load_sect(dtrace_hdl_t * dtp,dt_module_t * dmp,ctf_sect_t * ctsp)574 dt_module_load_sect(dtrace_hdl_t *dtp, dt_module_t *dmp, ctf_sect_t *ctsp)
575 {
576 	const char *s;
577 	size_t shstrs;
578 	GElf_Shdr sh;
579 	Elf_Data *dp;
580 	Elf_Scn *sp;
581 
582 	if (elf_getshdrstrndx(dmp->dm_elf, &shstrs) == -1)
583 		return (dt_set_errno(dtp, EDT_NOTLOADED));
584 
585 	for (sp = NULL; (sp = elf_nextscn(dmp->dm_elf, sp)) != NULL; ) {
586 		if (gelf_getshdr(sp, &sh) == NULL || sh.sh_type == SHT_NULL ||
587 		    (s = elf_strptr(dmp->dm_elf, shstrs, sh.sh_name)) == NULL)
588 			continue; /* skip any malformed sections */
589 
590 		if (sh.sh_type == ctsp->cts_type &&
591 		    sh.sh_entsize == ctsp->cts_entsize &&
592 		    strcmp(s, ctsp->cts_name) == 0)
593 			break; /* section matches specification */
594 	}
595 
596 	/*
597 	 * If the section isn't found, return success but leave cts_data set
598 	 * to NULL and cts_size set to zero for our caller.
599 	 */
600 	if (sp == NULL || (dp = elf_getdata(sp, NULL)) == NULL)
601 		return (0);
602 
603 #ifdef illumos
604 	ctsp->cts_data = dp->d_buf;
605 #else
606 	if ((ctsp->cts_data = malloc(dp->d_size)) == NULL)
607 		return (0);
608 	memcpy(ctsp->cts_data, dp->d_buf, dp->d_size);
609 #endif
610 	ctsp->cts_size = dp->d_size;
611 
612 	dt_dprintf("loaded %s [%s] (%lu bytes)\n",
613 	    dmp->dm_name, ctsp->cts_name, (ulong_t)ctsp->cts_size);
614 
615 	return (0);
616 }
617 
618 typedef struct dt_module_cb_arg {
619 	struct ps_prochandle *dpa_proc;
620 	dtrace_hdl_t *dpa_dtp;
621 	dt_module_t *dpa_dmp;
622 	uint_t dpa_count;
623 } dt_module_cb_arg_t;
624 
625 /* ARGSUSED */
626 static int
dt_module_load_proc_count(void * arg,const prmap_t * prmap,const char * obj)627 dt_module_load_proc_count(void *arg, const prmap_t *prmap, const char *obj)
628 {
629 	ctf_file_t *fp;
630 	dt_module_cb_arg_t *dcp = arg;
631 
632 	/* Try to grab a ctf container if it exists */
633 	fp = Pname_to_ctf(dcp->dpa_proc, obj);
634 	if (fp != NULL)
635 		dcp->dpa_count++;
636 	return (0);
637 }
638 
639 /* ARGSUSED */
640 static int
dt_module_load_proc_build(void * arg,const prmap_t * prmap,const char * obj)641 dt_module_load_proc_build(void *arg, const prmap_t *prmap, const char *obj)
642 {
643 	ctf_file_t *fp;
644 	char buf[MAXPATHLEN], *p;
645 	dt_module_cb_arg_t *dcp = arg;
646 	int count = dcp->dpa_count;
647 	Lmid_t lmid;
648 
649 	fp = Pname_to_ctf(dcp->dpa_proc, obj);
650 	if (fp == NULL)
651 		return (0);
652 	fp = ctf_dup(fp);
653 	if (fp == NULL)
654 		return (0);
655 	dcp->dpa_dmp->dm_libctfp[count] = fp;
656 	/*
657 	 * While it'd be nice to simply use objname here, because of our prior
658 	 * actions we'll always get a resolved object name to its on disk file.
659 	 * Like the pid provider, we need to tell a bit of a lie here. The type
660 	 * that the user thinks of is in terms of the libraries they requested,
661 	 * eg. libc.so.1, they don't care about the fact that it's
662 	 * libc_hwcap.so.1.
663 	 */
664 	(void) Pobjname(dcp->dpa_proc, prmap->pr_vaddr, buf, sizeof (buf));
665 	if ((p = strrchr(buf, '/')) == NULL)
666 		p = buf;
667 	else
668 		p++;
669 
670 	/*
671 	 * If for some reason we can't find a link map id for this module, which
672 	 * would be really quite weird. We instead just say the link map id is
673 	 * zero.
674 	 */
675 	if (Plmid(dcp->dpa_proc, prmap->pr_vaddr, &lmid) != 0)
676 		lmid = 0;
677 
678 	if (lmid == 0)
679 		dcp->dpa_dmp->dm_libctfn[count] = strdup(p);
680 	else
681 		(void) asprintf(&dcp->dpa_dmp->dm_libctfn[count],
682 		    "LM%x`%s", lmid, p);
683 	if (dcp->dpa_dmp->dm_libctfn[count] == NULL)
684 		return (1);
685 	ctf_setspecific(fp, dcp->dpa_dmp);
686 	dcp->dpa_count++;
687 	return (0);
688 }
689 
690 /*
691  * We've been asked to load data that belongs to another process. As such we're
692  * going to pgrab it at this instant, load everything that we might ever care
693  * about, and then drive on. The reason for this is that the process that we're
694  * interested in might be changing. As long as we have grabbed it, then this
695  * can't be a problem for us.
696  *
697  * For now, we're actually going to punt on most things and just try to get CTF
698  * data, nothing else. Basically this is only useful as a source of type
699  * information, we can't go and do the stacktrace lookups, etc.
700  */
701 static int
dt_module_load_proc(dtrace_hdl_t * dtp,dt_module_t * dmp)702 dt_module_load_proc(dtrace_hdl_t *dtp, dt_module_t *dmp)
703 {
704 	struct ps_prochandle *p;
705 	dt_module_cb_arg_t arg;
706 
707 	/*
708 	 * Note that on success we do not release this hold. We must hold this
709 	 * for our life time.
710 	 */
711 	p = dt_proc_grab(dtp, dmp->dm_pid, 0, PGRAB_RDONLY | PGRAB_FORCE);
712 	if (p == NULL) {
713 		dt_dprintf("failed to grab pid: %d\n", (int)dmp->dm_pid);
714 		return (dt_set_errno(dtp, EDT_CANTLOAD));
715 	}
716 	dt_proc_lock(dtp, p);
717 
718 	arg.dpa_proc = p;
719 	arg.dpa_dtp = dtp;
720 	arg.dpa_dmp = dmp;
721 	arg.dpa_count = 0;
722 	if (Pobject_iter_resolved(p, dt_module_load_proc_count, &arg) != 0) {
723 		dt_dprintf("failed to iterate objects\n");
724 		dt_proc_unlock(dtp, p);
725 		dt_proc_release(dtp, p);
726 		return (dt_set_errno(dtp, EDT_CANTLOAD));
727 	}
728 
729 	if (arg.dpa_count == 0) {
730 		dt_dprintf("no ctf data present\n");
731 		dt_proc_unlock(dtp, p);
732 		dt_proc_release(dtp, p);
733 		return (dt_set_errno(dtp, EDT_CANTLOAD));
734 	}
735 
736 	dmp->dm_libctfp = calloc(arg.dpa_count, sizeof (ctf_file_t *));
737 	if (dmp->dm_libctfp == NULL) {
738 		dt_proc_unlock(dtp, p);
739 		dt_proc_release(dtp, p);
740 		return (dt_set_errno(dtp, EDT_NOMEM));
741 	}
742 
743 	dmp->dm_libctfn = calloc(arg.dpa_count, sizeof (char *));
744 	if (dmp->dm_libctfn == NULL) {
745 		free(dmp->dm_libctfp);
746 		dt_proc_unlock(dtp, p);
747 		dt_proc_release(dtp, p);
748 		return (dt_set_errno(dtp, EDT_NOMEM));
749 	}
750 
751 	dmp->dm_nctflibs = arg.dpa_count;
752 
753 	arg.dpa_count = 0;
754 	if (Pobject_iter_resolved(p, dt_module_load_proc_build, &arg) != 0) {
755 		dt_proc_unlock(dtp, p);
756 		dt_module_unload(dtp, dmp);
757 		dt_proc_release(dtp, p);
758 		return (dt_set_errno(dtp, EDT_CANTLOAD));
759 	}
760 	assert(arg.dpa_count == dmp->dm_nctflibs);
761 	dt_dprintf("loaded %d ctf modules for pid %d\n", arg.dpa_count,
762 	    (int)dmp->dm_pid);
763 
764 	dt_proc_unlock(dtp, p);
765 	dt_proc_release(dtp, p);
766 	dmp->dm_flags |= DT_DM_LOADED;
767 
768 	return (0);
769 }
770 
771 int
dt_module_load(dtrace_hdl_t * dtp,dt_module_t * dmp)772 dt_module_load(dtrace_hdl_t *dtp, dt_module_t *dmp)
773 {
774 	if (dmp->dm_flags & DT_DM_LOADED)
775 		return (0); /* module is already loaded */
776 
777 	if (dmp->dm_pid != 0)
778 		return (dt_module_load_proc(dtp, dmp));
779 
780 	dmp->dm_ctdata.cts_name = ".SUNW_ctf";
781 	dmp->dm_ctdata.cts_type = SHT_PROGBITS;
782 	dmp->dm_ctdata.cts_flags = 0;
783 	dmp->dm_ctdata.cts_data = NULL;
784 	dmp->dm_ctdata.cts_size = 0;
785 	dmp->dm_ctdata.cts_entsize = 0;
786 	dmp->dm_ctdata.cts_offset = 0;
787 
788 	dmp->dm_symtab.cts_name = ".symtab";
789 	dmp->dm_symtab.cts_type = SHT_SYMTAB;
790 	dmp->dm_symtab.cts_flags = 0;
791 	dmp->dm_symtab.cts_data = NULL;
792 	dmp->dm_symtab.cts_size = 0;
793 	dmp->dm_symtab.cts_entsize = dmp->dm_ops == &dt_modops_64 ?
794 	    sizeof (Elf64_Sym) : sizeof (Elf32_Sym);
795 	dmp->dm_symtab.cts_offset = 0;
796 
797 	dmp->dm_strtab.cts_name = ".strtab";
798 	dmp->dm_strtab.cts_type = SHT_STRTAB;
799 	dmp->dm_strtab.cts_flags = 0;
800 	dmp->dm_strtab.cts_data = NULL;
801 	dmp->dm_strtab.cts_size = 0;
802 	dmp->dm_strtab.cts_entsize = 0;
803 	dmp->dm_strtab.cts_offset = 0;
804 
805 	/*
806 	 * Attempt to load the module's CTF section, symbol table section, and
807 	 * string table section.  Note that modules may not contain CTF data:
808 	 * this will result in a successful load_sect but data of size zero.
809 	 * We will then fail if dt_module_getctf() is called, as shown below.
810 	 */
811 	if (dt_module_load_sect(dtp, dmp, &dmp->dm_ctdata) == -1 ||
812 	    dt_module_load_sect(dtp, dmp, &dmp->dm_symtab) == -1 ||
813 	    dt_module_load_sect(dtp, dmp, &dmp->dm_strtab) == -1) {
814 		dt_module_unload(dtp, dmp);
815 		return (-1); /* dt_errno is set for us */
816 	}
817 
818 	/*
819 	 * Allocate the hash chains and hash buckets for symbol name lookup.
820 	 * This is relatively simple since the symbol table is of fixed size
821 	 * and is known in advance.  We allocate one extra element since we
822 	 * use element indices instead of pointers and zero is our sentinel.
823 	 */
824 	dmp->dm_nsymelems =
825 	    dmp->dm_symtab.cts_size / dmp->dm_symtab.cts_entsize;
826 
827 	dmp->dm_nsymbuckets = _dtrace_strbuckets;
828 	dmp->dm_symfree = 1;		/* first free element is index 1 */
829 
830 	dmp->dm_symbuckets = calloc(dmp->dm_nsymbuckets, sizeof (uint_t));
831 	dmp->dm_symchains = calloc(dmp->dm_nsymelems + 1, sizeof (dt_sym_t));
832 
833 	if (dmp->dm_symbuckets == NULL || dmp->dm_symchains == NULL) {
834 		dt_module_unload(dtp, dmp);
835 		return (dt_set_errno(dtp, EDT_NOMEM));
836 	}
837 
838 	/*
839 	 * Iterate over the symbol table data buffer and insert each symbol
840 	 * name into the name hash if the name and type are valid.  Then
841 	 * allocate the address map, fill it in, and sort it.
842 	 */
843 	dmp->dm_asrsv = dmp->dm_ops->do_syminit(dmp);
844 
845 	dt_dprintf("hashed %s [%s] (%u symbols)\n",
846 	    dmp->dm_name, dmp->dm_symtab.cts_name, dmp->dm_symfree - 1);
847 
848 	if ((dmp->dm_asmap = malloc(sizeof (void *) * dmp->dm_asrsv)) == NULL) {
849 		dt_module_unload(dtp, dmp);
850 		return (dt_set_errno(dtp, EDT_NOMEM));
851 	}
852 
853 	dmp->dm_ops->do_symsort(dmp);
854 
855 	dt_dprintf("sorted %s [%s] (%u symbols)\n",
856 	    dmp->dm_name, dmp->dm_symtab.cts_name, dmp->dm_aslen);
857 
858 	dmp->dm_flags |= DT_DM_LOADED;
859 	return (0);
860 }
861 
862 int
dt_module_hasctf(dtrace_hdl_t * dtp,dt_module_t * dmp)863 dt_module_hasctf(dtrace_hdl_t *dtp, dt_module_t *dmp)
864 {
865 	if (dmp->dm_pid != 0 && dmp->dm_nctflibs > 0)
866 		return (1);
867 	return (dt_module_getctf(dtp, dmp) != NULL);
868 }
869 
870 ctf_file_t *
dt_module_getctf(dtrace_hdl_t * dtp,dt_module_t * dmp)871 dt_module_getctf(dtrace_hdl_t *dtp, dt_module_t *dmp)
872 {
873 	const char *parent;
874 	dt_module_t *pmp;
875 	ctf_file_t *pfp;
876 	int model;
877 
878 	if (dmp->dm_ctfp != NULL || dt_module_load(dtp, dmp) != 0)
879 		return (dmp->dm_ctfp);
880 
881 	if (dmp->dm_ops == &dt_modops_64)
882 		model = CTF_MODEL_LP64;
883 	else
884 		model = CTF_MODEL_ILP32;
885 
886 	/*
887 	 * If the data model of the module does not match our program data
888 	 * model, then do not permit CTF from this module to be opened and
889 	 * returned to the compiler.  If we support mixed data models in the
890 	 * future for combined kernel/user tracing, this can be removed.
891 	 */
892 	if (dtp->dt_conf.dtc_ctfmodel != model) {
893 		(void) dt_set_errno(dtp, EDT_DATAMODEL);
894 		return (NULL);
895 	}
896 
897 	if (dmp->dm_ctdata.cts_size == 0) {
898 		(void) dt_set_errno(dtp, EDT_NOCTF);
899 		return (NULL);
900 	}
901 
902 	dmp->dm_ctfp = ctf_bufopen(&dmp->dm_ctdata,
903 	    &dmp->dm_symtab, &dmp->dm_strtab, &dtp->dt_ctferr);
904 
905 	if (dmp->dm_ctfp == NULL) {
906 		(void) dt_set_errno(dtp, EDT_CTF);
907 		return (NULL);
908 	}
909 
910 	(void) ctf_setmodel(dmp->dm_ctfp, model);
911 	ctf_setspecific(dmp->dm_ctfp, dmp);
912 
913 	if ((parent = ctf_parent_name(dmp->dm_ctfp)) != NULL) {
914 		if ((pmp = dt_module_create(dtp, parent)) == NULL ||
915 		    (pfp = dt_module_getctf(dtp, pmp)) == NULL) {
916 			if (pmp == NULL)
917 				(void) dt_set_errno(dtp, EDT_NOMEM);
918 			goto err;
919 		}
920 
921 		if (ctf_import(dmp->dm_ctfp, pfp) == CTF_ERR) {
922 			dtp->dt_ctferr = ctf_errno(dmp->dm_ctfp);
923 			(void) dt_set_errno(dtp, EDT_CTF);
924 			goto err;
925 		}
926 	}
927 
928 	dt_dprintf("loaded CTF container for %s (%p)\n",
929 	    dmp->dm_name, (void *)dmp->dm_ctfp);
930 
931 	return (dmp->dm_ctfp);
932 
933 err:
934 	ctf_close(dmp->dm_ctfp);
935 	dmp->dm_ctfp = NULL;
936 	return (NULL);
937 }
938 
939 /*ARGSUSED*/
940 void
dt_module_unload(dtrace_hdl_t * dtp,dt_module_t * dmp)941 dt_module_unload(dtrace_hdl_t *dtp, dt_module_t *dmp)
942 {
943 	int i;
944 
945 	ctf_close(dmp->dm_ctfp);
946 	dmp->dm_ctfp = NULL;
947 
948 #ifndef illumos
949 	if (dmp->dm_ctdata.cts_data != NULL) {
950 		free(dmp->dm_ctdata.cts_data);
951 	}
952 	if (dmp->dm_symtab.cts_data != NULL) {
953 		free(dmp->dm_symtab.cts_data);
954 	}
955 	if (dmp->dm_strtab.cts_data != NULL) {
956 		free(dmp->dm_strtab.cts_data);
957 	}
958 #endif
959 
960 	if (dmp->dm_libctfp != NULL) {
961 		for (i = 0; i < dmp->dm_nctflibs; i++) {
962 			ctf_close(dmp->dm_libctfp[i]);
963 			free(dmp->dm_libctfn[i]);
964 		}
965 		free(dmp->dm_libctfp);
966 		free(dmp->dm_libctfn);
967 		dmp->dm_libctfp = NULL;
968 		dmp->dm_nctflibs = 0;
969 	}
970 
971 	bzero(&dmp->dm_ctdata, sizeof (ctf_sect_t));
972 	bzero(&dmp->dm_symtab, sizeof (ctf_sect_t));
973 	bzero(&dmp->dm_strtab, sizeof (ctf_sect_t));
974 
975 	if (dmp->dm_symbuckets != NULL) {
976 		free(dmp->dm_symbuckets);
977 		dmp->dm_symbuckets = NULL;
978 	}
979 
980 	if (dmp->dm_symchains != NULL) {
981 		free(dmp->dm_symchains);
982 		dmp->dm_symchains = NULL;
983 	}
984 
985 	if (dmp->dm_asmap != NULL) {
986 		free(dmp->dm_asmap);
987 		dmp->dm_asmap = NULL;
988 	}
989 #if defined(__FreeBSD__)
990 	if (dmp->dm_sec_offsets != NULL) {
991 		free(dmp->dm_sec_offsets);
992 		dmp->dm_sec_offsets = NULL;
993 	}
994 #endif
995 	dmp->dm_symfree = 0;
996 	dmp->dm_nsymbuckets = 0;
997 	dmp->dm_nsymelems = 0;
998 	dmp->dm_asrsv = 0;
999 	dmp->dm_aslen = 0;
1000 
1001 	dmp->dm_text_va = 0;
1002 	dmp->dm_text_size = 0;
1003 	dmp->dm_data_va = 0;
1004 	dmp->dm_data_size = 0;
1005 	dmp->dm_bss_va = 0;
1006 	dmp->dm_bss_size = 0;
1007 
1008 	if (dmp->dm_extern != NULL) {
1009 		dt_idhash_destroy(dmp->dm_extern);
1010 		dmp->dm_extern = NULL;
1011 	}
1012 
1013 	(void) elf_end(dmp->dm_elf);
1014 	dmp->dm_elf = NULL;
1015 
1016 	dmp->dm_pid = 0;
1017 
1018 	dmp->dm_flags &= ~DT_DM_LOADED;
1019 }
1020 
1021 void
dt_module_destroy(dtrace_hdl_t * dtp,dt_module_t * dmp)1022 dt_module_destroy(dtrace_hdl_t *dtp, dt_module_t *dmp)
1023 {
1024 	uint_t h = dt_strtab_hash(dmp->dm_name, NULL) % dtp->dt_modbuckets;
1025 	dt_module_t **dmpp = &dtp->dt_mods[h];
1026 
1027 	dt_list_delete(&dtp->dt_modlist, dmp);
1028 	assert(dtp->dt_nmods != 0);
1029 	dtp->dt_nmods--;
1030 
1031 	/*
1032 	 * Now remove this module from its hash chain.  We expect to always
1033 	 * find the module on its hash chain, so in this loop we assert that
1034 	 * we don't run off the end of the list.
1035 	 */
1036 	while (*dmpp != dmp) {
1037 		dmpp = &((*dmpp)->dm_next);
1038 		assert(*dmpp != NULL);
1039 	}
1040 
1041 	*dmpp = dmp->dm_next;
1042 
1043 	dt_module_unload(dtp, dmp);
1044 	free(dmp);
1045 }
1046 
1047 /*
1048  * Insert a new external symbol reference into the specified module.  The new
1049  * symbol will be marked as undefined and is assigned a symbol index beyond
1050  * any existing cached symbols from this module.  We use the ident's di_data
1051  * field to store a pointer to a copy of the dtrace_syminfo_t for this symbol.
1052  */
1053 dt_ident_t *
dt_module_extern(dtrace_hdl_t * dtp,dt_module_t * dmp,const char * name,const dtrace_typeinfo_t * tip)1054 dt_module_extern(dtrace_hdl_t *dtp, dt_module_t *dmp,
1055     const char *name, const dtrace_typeinfo_t *tip)
1056 {
1057 	dtrace_syminfo_t *sip;
1058 	dt_ident_t *idp;
1059 	uint_t id;
1060 
1061 	if (dmp->dm_extern == NULL && (dmp->dm_extern = dt_idhash_create(
1062 	    "extern", NULL, dmp->dm_nsymelems, UINT_MAX)) == NULL) {
1063 		(void) dt_set_errno(dtp, EDT_NOMEM);
1064 		return (NULL);
1065 	}
1066 
1067 	if (dt_idhash_nextid(dmp->dm_extern, &id) == -1) {
1068 		(void) dt_set_errno(dtp, EDT_SYMOFLOW);
1069 		return (NULL);
1070 	}
1071 
1072 	if ((sip = malloc(sizeof (dtrace_syminfo_t))) == NULL) {
1073 		(void) dt_set_errno(dtp, EDT_NOMEM);
1074 		return (NULL);
1075 	}
1076 
1077 	idp = dt_idhash_insert(dmp->dm_extern, name, DT_IDENT_SYMBOL, 0, id,
1078 	    _dtrace_symattr, 0, &dt_idops_thaw, NULL, dtp->dt_gen);
1079 
1080 	if (idp == NULL) {
1081 		(void) dt_set_errno(dtp, EDT_NOMEM);
1082 		free(sip);
1083 		return (NULL);
1084 	}
1085 
1086 	sip->dts_object = dmp->dm_name;
1087 	sip->dts_name = idp->di_name;
1088 	sip->dts_id = idp->di_id;
1089 
1090 	idp->di_data = sip;
1091 	idp->di_ctfp = tip->dtt_ctfp;
1092 	idp->di_type = tip->dtt_type;
1093 
1094 	return (idp);
1095 }
1096 
1097 const char *
dt_module_modelname(dt_module_t * dmp)1098 dt_module_modelname(dt_module_t *dmp)
1099 {
1100 	if (dmp->dm_ops == &dt_modops_64)
1101 		return ("64-bit");
1102 	else
1103 		return ("32-bit");
1104 }
1105 
1106 /* ARGSUSED */
1107 int
dt_module_getlibid(dtrace_hdl_t * dtp,dt_module_t * dmp,const ctf_file_t * fp)1108 dt_module_getlibid(dtrace_hdl_t *dtp, dt_module_t *dmp, const ctf_file_t *fp)
1109 {
1110 	int i;
1111 
1112 	for (i = 0; i < dmp->dm_nctflibs; i++) {
1113 		if (dmp->dm_libctfp[i] == fp)
1114 			return (i);
1115 	}
1116 
1117 	return (-1);
1118 }
1119 
1120 /* ARGSUSED */
1121 ctf_file_t *
dt_module_getctflib(dtrace_hdl_t * dtp,dt_module_t * dmp,const char * name)1122 dt_module_getctflib(dtrace_hdl_t *dtp, dt_module_t *dmp, const char *name)
1123 {
1124 	int i;
1125 
1126 	for (i = 0; i < dmp->dm_nctflibs; i++) {
1127 		if (strcmp(dmp->dm_libctfn[i], name) == 0)
1128 			return (dmp->dm_libctfp[i]);
1129 	}
1130 
1131 	return (NULL);
1132 }
1133 
1134 /*
1135  * Update our module cache by adding an entry for the specified module 'name'.
1136  * We create the dt_module_t and populate it using /system/object/<name>/.
1137  *
1138  * On FreeBSD, the module name is passed as the full module file name,
1139  * including the path.
1140  */
1141 static void
1142 #if defined(illumos) || defined(__NetBSD__)
dt_module_update(dtrace_hdl_t * dtp,const char * name)1143 dt_module_update(dtrace_hdl_t *dtp, const char *name)
1144 #elif defined(__FreeBSD__)
1145 dt_module_update(dtrace_hdl_t *dtp, struct kld_file_stat *k_stat)
1146 #endif
1147 {
1148 	char fname[MAXPATHLEN];
1149 	struct stat64 st;
1150 	int fd, err, bits;
1151 #ifdef __FreeBSD__
1152 	struct module_stat ms;
1153 	dt_kmodule_t *dkmp;
1154 	uint_t h;
1155 	int modid;
1156 #endif
1157 
1158 	dt_module_t *dmp;
1159 	const char *s;
1160 	size_t shstrs;
1161 	GElf_Shdr sh;
1162 	Elf_Data *dp;
1163 	Elf_Scn *sp;
1164 
1165 #ifdef illumos
1166 	(void) snprintf(fname, sizeof (fname),
1167 	    "%s/%s/object", OBJFS_ROOT, name);
1168 #elif defined(__FreeBSD__)
1169 	GElf_Ehdr ehdr;
1170 	GElf_Phdr ph;
1171 	char name[MAXPATHLEN];
1172 	uintptr_t mapbase, alignmask;
1173 	int i = 0;
1174 	int is_elf_obj;
1175 
1176 	(void) strlcpy(name, k_stat->name, sizeof(name));
1177 	(void) strlcpy(fname, k_stat->pathname, sizeof(fname));
1178 #elif defined(__NetBSD__)
1179 	int mib_osrel[2] = { CTL_KERN, KERN_OSRELEASE };
1180 	int mib_mach[2] = { CTL_HW, HW_MACHINE };
1181 	char osrel[64];
1182 	char machine[64];
1183 	size_t len;
1184 	uintptr_t mapbase;
1185 	int i;
1186 	bool ismod;
1187 
1188 	if (strcmp("netbsd", name) == 0) {
1189 		strlcpy(fname, _PATH_KSYMS, sizeof fname);
1190 		ismod = false;
1191 	} else {
1192 
1193 		/* build stand module path from system */
1194 		len = sizeof(osrel);
1195 		if (sysctl(mib_osrel, 2, osrel, &len, NULL, 0) == -1) {
1196 			dt_dprintf("sysctl osrel failed: %s\n",
1197 				strerror(errno));
1198 		    return;
1199 		}
1200 
1201 		len = sizeof(machine);
1202 		if (sysctl(mib_mach, 2, machine, &len, NULL, 0) == -1) {
1203 			dt_dprintf("sysctl machine failed: %s\n",
1204 				strerror(errno));
1205 		    return;
1206 		}
1207 
1208 		(void) snprintf(fname, sizeof (fname),
1209 		    "/stand/%s/%s/modules/%s/%s.kmod", machine, osrel, name, name);
1210 		ismod = true;
1211 	}
1212 #endif
1213 
1214 	if ((fd = open(fname, O_RDONLY)) == -1 || fstat64(fd, &st) == -1 ||
1215 	    (dmp = dt_module_create(dtp, name)) == NULL) {
1216 		dt_dprintf("failed to open %s: %s\n", fname, strerror(errno));
1217 		(void) close(fd);
1218 		return;
1219 	}
1220 
1221 	/*
1222 	 * Since the module can unload out from under us (and /system/object
1223 	 * will return ENOENT), tell libelf to cook the entire file now and
1224 	 * then close the underlying file descriptor immediately.  If this
1225 	 * succeeds, we know that we can continue safely using dmp->dm_elf.
1226 	 */
1227 	dmp->dm_elf = elf_begin(fd, ELF_C_READ, NULL);
1228 	err = elf_cntl(dmp->dm_elf, ELF_C_FDREAD);
1229 	(void) close(fd);
1230 
1231 	if (dmp->dm_elf == NULL || err == -1 ||
1232 	    elf_getshdrstrndx(dmp->dm_elf, &shstrs) == -1) {
1233 		dt_dprintf("failed to load %s: %s\n",
1234 		    fname, elf_errmsg(elf_errno()));
1235 		dt_module_destroy(dtp, dmp);
1236 		return;
1237 	}
1238 
1239 	switch (gelf_getclass(dmp->dm_elf)) {
1240 	case ELFCLASS32:
1241 		dmp->dm_ops = &dt_modops_32;
1242 		bits = 32;
1243 		break;
1244 	case ELFCLASS64:
1245 		dmp->dm_ops = &dt_modops_64;
1246 		bits = 64;
1247 		break;
1248 	default:
1249 		dt_dprintf("failed to load %s: unknown ELF class\n", fname);
1250 		dt_module_destroy(dtp, dmp);
1251 		return;
1252 	}
1253 #if defined(__FreeBSD__)
1254 	mapbase = (uintptr_t)k_stat->address;
1255 	gelf_getehdr(dmp->dm_elf, &ehdr);
1256 	is_elf_obj = (ehdr.e_type == ET_REL);
1257 	if (is_elf_obj) {
1258 		dmp->dm_sec_offsets =
1259 		    malloc(ehdr.e_shnum * sizeof(*dmp->dm_sec_offsets));
1260 		if (dmp->dm_sec_offsets == NULL) {
1261 			dt_dprintf("failed to allocate memory\n");
1262 			dt_module_destroy(dtp, dmp);
1263 			return;
1264 		}
1265 	}
1266 #endif
1267 #ifdef __NetBSD__
1268 	mapbase = 0;
1269 	if (ismod) {
1270 #define	MAXMODULES 512
1271 		modstat_t modstat_buf[MAXMODULES], *ms;
1272 		struct iovec iov = { modstat_buf, sizeof(modstat_buf) };
1273 
1274 		if (modctl(MODCTL_STAT, &iov) < 0) {
1275 			dt_dprintf("failed to get list of kernel modules: %s\n",
1276 				   strerror(errno));
1277 			return;
1278 		}
1279 
1280 		for (i = 0; i < MAXMODULES; i++) {
1281 			ms = &modstat_buf[i];
1282 			if (!strcmp(name, ms->ms_name)) {
1283 				mapbase = ms->ms_addr;
1284 				break;
1285 			}
1286 		}
1287 		if (i == MAXMODULES) {
1288 			dt_dprintf("module %s not found\n", name);
1289 			return;
1290 		}
1291 		dmp->dm_reloc_offset = (void *)mapbase;
1292 	}
1293 #endif
1294 
1295 	/*
1296 	 * Iterate over the section headers locating various sections of
1297 	 * interest and use their attributes to flesh out the dt_module_t.
1298 	 */
1299 	for (sp = NULL; (sp = elf_nextscn(dmp->dm_elf, sp)) != NULL; ) {
1300 		if (gelf_getshdr(sp, &sh) == NULL || sh.sh_type == SHT_NULL ||
1301 		    (s = elf_strptr(dmp->dm_elf, shstrs, sh.sh_name)) == NULL)
1302 			continue; /* skip any malformed sections */
1303 #if defined(__FreeBSD__)
1304 		if (sh.sh_size == 0)
1305 			continue;
1306 		if (sh.sh_type == SHT_PROGBITS || sh.sh_type == SHT_NOBITS) {
1307 			alignmask = sh.sh_addralign - 1;
1308 			mapbase += alignmask;
1309 			mapbase &= ~alignmask;
1310 			sh.sh_addr = mapbase;
1311 			if (is_elf_obj)
1312 				dmp->dm_sec_offsets[elf_ndxscn(sp)] = sh.sh_addr;
1313 			mapbase += sh.sh_size;
1314 		}
1315 #endif
1316 		if (strcmp(s, ".text") == 0) {
1317 			dmp->dm_text_size = sh.sh_size;
1318 			dmp->dm_text_va = sh.sh_addr;
1319 		} else if (strcmp(s, ".data") == 0) {
1320 			dmp->dm_data_size = sh.sh_size;
1321 			dmp->dm_data_va = sh.sh_addr;
1322 		} else if (strcmp(s, ".bss") == 0) {
1323 			dmp->dm_bss_size = sh.sh_size;
1324 			dmp->dm_bss_va = sh.sh_addr;
1325 		} else if (strcmp(s, ".info") == 0 &&
1326 		    (dp = elf_getdata(sp, NULL)) != NULL) {
1327 			bcopy(dp->d_buf, &dmp->dm_info,
1328 			    MIN(sh.sh_size, sizeof (dmp->dm_info)));
1329 		} else if (strcmp(s, ".filename") == 0 &&
1330 		    (dp = elf_getdata(sp, NULL)) != NULL) {
1331 			(void) strlcpy(dmp->dm_file,
1332 			    dp->d_buf, sizeof (dmp->dm_file));
1333 		}
1334 	}
1335 
1336 	dmp->dm_flags |= DT_DM_KERNEL;
1337 #ifdef illumos
1338 	dmp->dm_modid = (int)OBJFS_MODID(st.st_ino);
1339 #endif /* illumos */
1340 #ifdef __FreeBSD__
1341 	/*
1342 	 * Include .rodata and special sections into .text.
1343 	 * This depends on default section layout produced by GNU ld
1344 	 * for ELF objects and libraries:
1345 	 * [Text][R/O data][R/W data][Dynamic][BSS][Non loadable]
1346 	 */
1347 	dmp->dm_text_size = dmp->dm_data_va - dmp->dm_text_va;
1348 #if defined(__i386__)
1349 	/*
1350 	 * Find the first load section and figure out the relocation
1351 	 * offset for the symbols. The kernel module will not need
1352 	 * relocation, but the kernel linker modules will.
1353 	 */
1354 	for (i = 0; gelf_getphdr(dmp->dm_elf, i, &ph) != NULL; i++) {
1355 		if (ph.p_type == PT_LOAD) {
1356 			dmp->dm_reloc_offset = k_stat->address - ph.p_vaddr;
1357 			break;
1358 		}
1359 	}
1360 #endif
1361 #endif /* __FreeBSD__ */
1362 #ifdef __NetBSD__
1363 	if (ismod) {
1364 		dmp->dm_text_va = mapbase;
1365 		dmp->dm_data_va = 0;
1366 		dmp->dm_data_size = 0;
1367 		dmp->dm_bss_va = 0;
1368 		dmp->dm_bss_size = 0;
1369 	}
1370 #endif
1371 
1372 	if (dmp->dm_info.objfs_info_primary)
1373 		dmp->dm_flags |= DT_DM_PRIMARY;
1374 
1375 #ifdef __FreeBSD__
1376 	ms.version = sizeof(ms);
1377 	for (modid = kldfirstmod(k_stat->id); modid > 0;
1378 	    modid = modnext(modid)) {
1379 		if (modstat(modid, &ms) != 0) {
1380 			dt_dprintf("modstat failed for id %d in %s: %s\n",
1381 			    modid, k_stat->name, strerror(errno));
1382 			continue;
1383 		}
1384 		if (dt_kmodule_lookup(dtp, ms.name) != NULL)
1385 			continue;
1386 
1387 		dkmp = malloc(sizeof (*dkmp));
1388 		if (dkmp == NULL) {
1389 			dt_dprintf("failed to allocate memory\n");
1390 			dt_module_destroy(dtp, dmp);
1391 			return;
1392 		}
1393 
1394 		h = dt_strtab_hash(ms.name, NULL) % dtp->dt_modbuckets;
1395 		dkmp->dkm_next = dtp->dt_kmods[h];
1396 		dkmp->dkm_name = strdup(ms.name);
1397 		dkmp->dkm_module = dmp;
1398 		dtp->dt_kmods[h] = dkmp;
1399 	}
1400 #endif
1401 
1402 	dt_dprintf("opened %d-bit module %s (%s) [%d]\n",
1403 	    bits, dmp->dm_name, dmp->dm_file, dmp->dm_modid);
1404 }
1405 
1406 /*
1407  * Unload all the loaded modules and then refresh the module cache with the
1408  * latest list of loaded modules and their address ranges.
1409  */
1410 void
dtrace_update(dtrace_hdl_t * dtp)1411 dtrace_update(dtrace_hdl_t *dtp)
1412 {
1413 	dt_module_t *dmp;
1414 #ifdef illumos
1415 	DIR *dirp;
1416 #elif defined(__FreeBSD__)
1417 	int fileid;
1418 #endif
1419 
1420 	for (dmp = dt_list_next(&dtp->dt_modlist);
1421 	    dmp != NULL; dmp = dt_list_next(dmp))
1422 		dt_module_unload(dtp, dmp);
1423 
1424 #ifdef illumos
1425 	/*
1426 	 * Open /system/object and attempt to create a libdtrace module for
1427 	 * each kernel module that is loaded on the current system.
1428 	 */
1429 	if (!(dtp->dt_oflags & DTRACE_O_NOSYS) &&
1430 	    (dirp = opendir(OBJFS_ROOT)) != NULL) {
1431 		struct dirent *dp;
1432 
1433 		while ((dp = readdir(dirp)) != NULL) {
1434 			if (dp->d_name[0] != '.')
1435 				dt_module_update(dtp, dp->d_name);
1436 		}
1437 
1438 		(void) closedir(dirp);
1439 	}
1440 #elif defined(__FreeBSD__)
1441 	/*
1442 	 * Use FreeBSD's kernel loader interface to discover what kernel
1443 	 * modules are loaded and create a libdtrace module for each one.
1444 	 */
1445 	for (fileid = kldnext(0); fileid > 0; fileid = kldnext(fileid)) {
1446 		struct kld_file_stat k_stat;
1447 		k_stat.version = sizeof(k_stat);
1448 		if (kldstat(fileid, &k_stat) == 0)
1449 			dt_module_update(dtp, &k_stat);
1450 	}
1451 #elif defined(__NetBSD__)
1452 	size_t len;
1453 	struct iovec iov;
1454 	modstat_t *ms;
1455 
1456 	dt_module_update(dtp, "netbsd");
1457 	for (len = 8192;;) {
1458 		iov.iov_base = malloc(len);
1459 		iov.iov_len = len;
1460 		if (modctl(MODCTL_STAT, &iov)) {
1461 			free(iov.iov_base);
1462 			iov.iov_len = 0;
1463 			break;
1464 		}
1465 		if (len >= iov.iov_len) {
1466 			break;
1467 		}
1468 		free(iov.iov_base);
1469 		len = iov.iov_len;
1470 	}
1471 	len = iov.iov_len / sizeof(modstat_t);
1472 	for (ms = iov.iov_base; len != 0; ms++, len--) {
1473 		if (ms->ms_source != MODULE_SOURCE_FILESYS)
1474 			continue;
1475 		dt_module_update(dtp, ms->ms_name);
1476 	}
1477 #endif
1478 
1479 	/*
1480 	 * Look up all the macro identifiers and set di_id to the latest value.
1481 	 * This code collaborates with dt_lex.l on the use of di_id.  We will
1482 	 * need to implement something fancier if we need to support non-ints.
1483 	 */
1484 	dt_idhash_lookup(dtp->dt_macros, "egid")->di_id = getegid();
1485 	dt_idhash_lookup(dtp->dt_macros, "euid")->di_id = geteuid();
1486 	dt_idhash_lookup(dtp->dt_macros, "gid")->di_id = getgid();
1487 	dt_idhash_lookup(dtp->dt_macros, "pid")->di_id = getpid();
1488 	dt_idhash_lookup(dtp->dt_macros, "pgid")->di_id = getpgid(0);
1489 	dt_idhash_lookup(dtp->dt_macros, "ppid")->di_id = getppid();
1490 #ifdef illumos
1491 	dt_idhash_lookup(dtp->dt_macros, "projid")->di_id = getprojid();
1492 #endif
1493 	dt_idhash_lookup(dtp->dt_macros, "sid")->di_id = getsid(0);
1494 #ifdef illumos
1495 	dt_idhash_lookup(dtp->dt_macros, "taskid")->di_id = gettaskid();
1496 #endif
1497 	dt_idhash_lookup(dtp->dt_macros, "uid")->di_id = getuid();
1498 
1499 	/*
1500 	 * Cache the pointers to the modules representing the base executable
1501 	 * and the run-time linker in the dtrace client handle. Note that on
1502 	 * x86 krtld is folded into unix, so if we don't find it, use unix
1503 	 * instead.
1504 	 */
1505 	dtp->dt_exec = dt_module_lookup_by_name(dtp, "genunix");
1506 	dtp->dt_rtld = dt_module_lookup_by_name(dtp, "krtld");
1507 	if (dtp->dt_rtld == NULL)
1508 		dtp->dt_rtld = dt_module_lookup_by_name(dtp, "unix");
1509 
1510 	/*
1511 	 * If this is the first time we are initializing the module list,
1512 	 * remove the module for genunix from the module list and then move it
1513 	 * to the front of the module list.  We do this so that type and symbol
1514 	 * queries encounter genunix and thereby optimize for the common case
1515 	 * in dtrace_lookup_by_name() and dtrace_lookup_by_type(), below.
1516 	 */
1517 	if (dtp->dt_exec != NULL &&
1518 	    dtp->dt_cdefs == NULL && dtp->dt_ddefs == NULL) {
1519 		dt_list_delete(&dtp->dt_modlist, dtp->dt_exec);
1520 		dt_list_prepend(&dtp->dt_modlist, dtp->dt_exec);
1521 	}
1522 }
1523 
1524 static dt_module_t *
dt_module_from_object(dtrace_hdl_t * dtp,const char * object)1525 dt_module_from_object(dtrace_hdl_t *dtp, const char *object)
1526 {
1527 	int err = EDT_NOMOD;
1528 	dt_module_t *dmp;
1529 
1530 	switch ((uintptr_t)object) {
1531 	case (uintptr_t)DTRACE_OBJ_EXEC:
1532 		dmp = dtp->dt_exec;
1533 		break;
1534 	case (uintptr_t)DTRACE_OBJ_RTLD:
1535 		dmp = dtp->dt_rtld;
1536 		break;
1537 	case (uintptr_t)DTRACE_OBJ_CDEFS:
1538 		dmp = dtp->dt_cdefs;
1539 		break;
1540 	case (uintptr_t)DTRACE_OBJ_DDEFS:
1541 		dmp = dtp->dt_ddefs;
1542 		break;
1543 	default:
1544 		dmp = dt_module_create(dtp, object);
1545 		err = EDT_NOMEM;
1546 	}
1547 
1548 	if (dmp == NULL)
1549 		(void) dt_set_errno(dtp, err);
1550 
1551 	return (dmp);
1552 }
1553 
1554 /*
1555  * Exported interface to look up a symbol by name.  We return the GElf_Sym and
1556  * complete symbol information for the matching symbol.
1557  */
1558 int
dtrace_lookup_by_name(dtrace_hdl_t * dtp,const char * object,const char * name,GElf_Sym * symp,dtrace_syminfo_t * sip)1559 dtrace_lookup_by_name(dtrace_hdl_t *dtp, const char *object, const char *name,
1560     GElf_Sym *symp, dtrace_syminfo_t *sip)
1561 {
1562 	dt_module_t *dmp;
1563 	dt_ident_t *idp;
1564 	uint_t n, id;
1565 	GElf_Sym sym;
1566 
1567 	uint_t mask = 0; /* mask of dt_module flags to match */
1568 	uint_t bits = 0; /* flag bits that must be present */
1569 
1570 	if (object != DTRACE_OBJ_EVERY &&
1571 	    object != DTRACE_OBJ_KMODS &&
1572 	    object != DTRACE_OBJ_UMODS) {
1573 		if ((dmp = dt_module_from_object(dtp, object)) == NULL)
1574 			return (-1); /* dt_errno is set for us */
1575 
1576 		if (dt_module_load(dtp, dmp) == -1)
1577 			return (-1); /* dt_errno is set for us */
1578 		n = 1;
1579 
1580 	} else {
1581 		if (object == DTRACE_OBJ_KMODS)
1582 			mask = bits = DT_DM_KERNEL;
1583 		else if (object == DTRACE_OBJ_UMODS)
1584 			mask = DT_DM_KERNEL;
1585 
1586 		dmp = dt_list_next(&dtp->dt_modlist);
1587 		n = dtp->dt_nmods;
1588 	}
1589 
1590 	if (symp == NULL)
1591 		symp = &sym;
1592 
1593 	for (; n > 0; n--, dmp = dt_list_next(dmp)) {
1594 		if ((dmp->dm_flags & mask) != bits)
1595 			continue; /* failed to match required attributes */
1596 
1597 		if (dt_module_load(dtp, dmp) == -1)
1598 			continue; /* failed to load symbol table */
1599 
1600 		if (dmp->dm_ops->do_symname(dmp, name, symp, &id) != NULL) {
1601 			if (sip != NULL) {
1602 				sip->dts_object = dmp->dm_name;
1603 				sip->dts_name = (const char *)
1604 				    dmp->dm_strtab.cts_data + symp->st_name;
1605 				sip->dts_id = id;
1606 			}
1607 			return (0);
1608 		}
1609 
1610 		if (dmp->dm_extern != NULL &&
1611 		    (idp = dt_idhash_lookup(dmp->dm_extern, name)) != NULL) {
1612 			if (symp != &sym) {
1613 				symp->st_name = (uintptr_t)idp->di_name;
1614 				symp->st_info =
1615 				    GELF_ST_INFO(STB_GLOBAL, STT_NOTYPE);
1616 				symp->st_other = 0;
1617 				symp->st_shndx = SHN_UNDEF;
1618 				symp->st_value = 0;
1619 				symp->st_size =
1620 				    ctf_type_size(idp->di_ctfp, idp->di_type);
1621 			}
1622 
1623 			if (sip != NULL) {
1624 				sip->dts_object = dmp->dm_name;
1625 				sip->dts_name = idp->di_name;
1626 				sip->dts_id = idp->di_id;
1627 			}
1628 
1629 			return (0);
1630 		}
1631 	}
1632 
1633 	return (dt_set_errno(dtp, EDT_NOSYM));
1634 }
1635 
1636 /*
1637  * Exported interface to look up a symbol by address.  We return the GElf_Sym
1638  * and complete symbol information for the matching symbol.
1639  */
1640 int
dtrace_lookup_by_addr(dtrace_hdl_t * dtp,GElf_Addr addr,GElf_Sym * symp,dtrace_syminfo_t * sip)1641 dtrace_lookup_by_addr(dtrace_hdl_t *dtp, GElf_Addr addr,
1642     GElf_Sym *symp, dtrace_syminfo_t *sip)
1643 {
1644 	dt_module_t *dmp;
1645 	uint_t id;
1646 	const dtrace_vector_t *v = dtp->dt_vector;
1647 
1648 	if (v != NULL)
1649 		return (v->dtv_lookup_by_addr(dtp->dt_varg, addr, symp, sip));
1650 
1651 	for (dmp = dt_list_next(&dtp->dt_modlist); dmp != NULL;
1652 	    dmp = dt_list_next(dmp)) {
1653 
1654 		if (addr - dmp->dm_text_va < dmp->dm_text_size ||
1655 		    addr - dmp->dm_data_va < dmp->dm_data_size ||
1656 		    addr - dmp->dm_bss_va < dmp->dm_bss_size)
1657 			break;
1658 	}
1659 
1660 	if (dmp == NULL)
1661 		return (dt_set_errno(dtp, EDT_NOSYMADDR));
1662 
1663 	if (dt_module_load(dtp, dmp) == -1)
1664 		return (-1); /* dt_errno is set for us */
1665 
1666 	if (symp != NULL) {
1667 		if (dmp->dm_ops->do_symaddr(dmp, addr, symp, &id) == NULL)
1668 			return (dt_set_errno(dtp, EDT_NOSYMADDR));
1669 	}
1670 
1671 	if (sip != NULL) {
1672 		sip->dts_object = dmp->dm_name;
1673 
1674 		if (symp != NULL) {
1675 			sip->dts_name = (const char *)
1676 			    dmp->dm_strtab.cts_data + symp->st_name;
1677 			sip->dts_id = id;
1678 		} else {
1679 			sip->dts_name = NULL;
1680 			sip->dts_id = 0;
1681 		}
1682 	}
1683 
1684 	return (0);
1685 }
1686 
1687 int
dtrace_lookup_by_type(dtrace_hdl_t * dtp,const char * object,const char * name,dtrace_typeinfo_t * tip)1688 dtrace_lookup_by_type(dtrace_hdl_t *dtp, const char *object, const char *name,
1689     dtrace_typeinfo_t *tip)
1690 {
1691 	dtrace_typeinfo_t ti;
1692 	dt_module_t *dmp;
1693 	int found = 0;
1694 	ctf_id_t id = CTF_ERR;	// XXX: gcc
1695 	uint_t n, i;
1696 	int justone;
1697 	ctf_file_t *fp = NULL;	// XXX: gcc
1698 	char *buf, *p, *q;
1699 
1700 	uint_t mask = 0; /* mask of dt_module flags to match */
1701 	uint_t bits = 0; /* flag bits that must be present */
1702 
1703 	if (object != DTRACE_OBJ_EVERY &&
1704 	    object != DTRACE_OBJ_KMODS &&
1705 	    object != DTRACE_OBJ_UMODS) {
1706 		if ((dmp = dt_module_from_object(dtp, object)) == NULL)
1707 			return (-1); /* dt_errno is set for us */
1708 
1709 		if (dt_module_load(dtp, dmp) == -1)
1710 			return (-1); /* dt_errno is set for us */
1711 		n = 1;
1712 		justone = 1;
1713 	} else {
1714 		if (object == DTRACE_OBJ_KMODS)
1715 			mask = bits = DT_DM_KERNEL;
1716 		else if (object == DTRACE_OBJ_UMODS)
1717 			mask = DT_DM_KERNEL;
1718 
1719 		dmp = dt_list_next(&dtp->dt_modlist);
1720 		n = dtp->dt_nmods;
1721 		justone = 0;
1722 	}
1723 
1724 	if (tip == NULL)
1725 		tip = &ti;
1726 
1727 	for (; n > 0; n--, dmp = dt_list_next(dmp)) {
1728 		if ((dmp->dm_flags & mask) != bits)
1729 			continue; /* failed to match required attributes */
1730 
1731 		/*
1732 		 * If we can't load the CTF container, continue on to the next
1733 		 * module.  If our search was scoped to only one module then
1734 		 * return immediately leaving dt_errno unmodified.
1735 		 */
1736 		if (dt_module_hasctf(dtp, dmp) == 0) {
1737 			if (justone)
1738 				return (-1);
1739 			continue;
1740 		}
1741 
1742 		/*
1743 		 * Look up the type in the module's CTF container.  If our
1744 		 * match is a forward declaration tag, save this choice in
1745 		 * 'tip' and keep going in the hope that we will locate the
1746 		 * underlying structure definition.  Otherwise just return.
1747 		 */
1748 		if (dmp->dm_pid == 0) {
1749 			id = ctf_lookup_by_name(dmp->dm_ctfp, name);
1750 			fp = dmp->dm_ctfp;
1751 		} else {
1752 			if ((p = strchr(name, '`')) != NULL) {
1753 				buf = strdup(name);
1754 				if (buf == NULL)
1755 					return (dt_set_errno(dtp, EDT_NOMEM));
1756 				p = strchr(buf, '`');
1757 				if ((q = strchr(p + 1, '`')) != NULL)
1758 					p = q;
1759 				*p = '\0';
1760 				fp = dt_module_getctflib(dtp, dmp, buf);
1761 				if (fp == NULL || (id = ctf_lookup_by_name(fp,
1762 				    p + 1)) == CTF_ERR)
1763 					id = CTF_ERR;
1764 				free(buf);
1765 			} else {
1766 				for (i = 0; i < dmp->dm_nctflibs; i++) {
1767 					fp = dmp->dm_libctfp[i];
1768 					id = ctf_lookup_by_name(fp, name);
1769 					if (id != CTF_ERR)
1770 						break;
1771 				}
1772 			}
1773 		}
1774 		if (id != CTF_ERR) {
1775 			tip->dtt_object = dmp->dm_name;
1776 			tip->dtt_ctfp = fp;
1777 			tip->dtt_type = id;
1778 			if (ctf_type_kind(fp, ctf_type_resolve(fp, id)) !=
1779 			    CTF_K_FORWARD)
1780 				return (0);
1781 
1782 			found++;
1783 		}
1784 	}
1785 
1786 	if (found == 0)
1787 		return (dt_set_errno(dtp, EDT_NOTYPE));
1788 
1789 	return (0);
1790 }
1791 
1792 int
dtrace_symbol_type(dtrace_hdl_t * dtp,const GElf_Sym * symp,const dtrace_syminfo_t * sip,dtrace_typeinfo_t * tip)1793 dtrace_symbol_type(dtrace_hdl_t *dtp, const GElf_Sym *symp,
1794     const dtrace_syminfo_t *sip, dtrace_typeinfo_t *tip)
1795 {
1796 	dt_module_t *dmp;
1797 
1798 	tip->dtt_object = NULL;
1799 	tip->dtt_ctfp = NULL;
1800 	tip->dtt_type = CTF_ERR;
1801 	tip->dtt_flags = 0;
1802 
1803 	if ((dmp = dt_module_lookup_by_name(dtp, sip->dts_object)) == NULL)
1804 		return (dt_set_errno(dtp, EDT_NOMOD));
1805 
1806 	if (symp->st_shndx == SHN_UNDEF && dmp->dm_extern != NULL) {
1807 		dt_ident_t *idp =
1808 		    dt_idhash_lookup(dmp->dm_extern, sip->dts_name);
1809 
1810 		if (idp == NULL)
1811 			return (dt_set_errno(dtp, EDT_NOSYM));
1812 
1813 		tip->dtt_ctfp = idp->di_ctfp;
1814 		tip->dtt_type = idp->di_type;
1815 
1816 	} else if (GELF_ST_TYPE(symp->st_info) != STT_FUNC) {
1817 		if (dt_module_getctf(dtp, dmp) == NULL)
1818 			return (-1); /* errno is set for us */
1819 
1820 		tip->dtt_ctfp = dmp->dm_ctfp;
1821 		tip->dtt_type = ctf_lookup_by_symbol(dmp->dm_ctfp, sip->dts_id);
1822 
1823 		if (tip->dtt_type == CTF_ERR) {
1824 			dtp->dt_ctferr = ctf_errno(tip->dtt_ctfp);
1825 			return (dt_set_errno(dtp, EDT_CTF));
1826 		}
1827 
1828 	} else {
1829 		tip->dtt_ctfp = DT_FPTR_CTFP(dtp);
1830 		tip->dtt_type = DT_FPTR_TYPE(dtp);
1831 	}
1832 
1833 	tip->dtt_object = dmp->dm_name;
1834 	return (0);
1835 }
1836 
1837 static dtrace_objinfo_t *
dt_module_info(const dt_module_t * dmp,dtrace_objinfo_t * dto)1838 dt_module_info(const dt_module_t *dmp, dtrace_objinfo_t *dto)
1839 {
1840 	dto->dto_name = dmp->dm_name;
1841 	dto->dto_file = dmp->dm_file;
1842 	dto->dto_id = dmp->dm_modid;
1843 	dto->dto_flags = 0;
1844 
1845 	if (dmp->dm_flags & DT_DM_KERNEL)
1846 		dto->dto_flags |= DTRACE_OBJ_F_KERNEL;
1847 	if (dmp->dm_flags & DT_DM_PRIMARY)
1848 		dto->dto_flags |= DTRACE_OBJ_F_PRIMARY;
1849 
1850 	dto->dto_text_va = dmp->dm_text_va;
1851 	dto->dto_text_size = dmp->dm_text_size;
1852 	dto->dto_data_va = dmp->dm_data_va;
1853 	dto->dto_data_size = dmp->dm_data_size;
1854 	dto->dto_bss_va = dmp->dm_bss_va;
1855 	dto->dto_bss_size = dmp->dm_bss_size;
1856 
1857 	return (dto);
1858 }
1859 
1860 int
dtrace_object_iter(dtrace_hdl_t * dtp,dtrace_obj_f * func,void * data)1861 dtrace_object_iter(dtrace_hdl_t *dtp, dtrace_obj_f *func, void *data)
1862 {
1863 	const dt_module_t *dmp = dt_list_next(&dtp->dt_modlist);
1864 	dtrace_objinfo_t dto;
1865 	int rv;
1866 
1867 	for (; dmp != NULL; dmp = dt_list_next(dmp)) {
1868 		if ((rv = (*func)(dtp, dt_module_info(dmp, &dto), data)) != 0)
1869 			return (rv);
1870 	}
1871 
1872 	return (0);
1873 }
1874 
1875 int
dtrace_object_info(dtrace_hdl_t * dtp,const char * object,dtrace_objinfo_t * dto)1876 dtrace_object_info(dtrace_hdl_t *dtp, const char *object, dtrace_objinfo_t *dto)
1877 {
1878 	dt_module_t *dmp;
1879 
1880 	if (object == DTRACE_OBJ_EVERY || object == DTRACE_OBJ_KMODS ||
1881 	    object == DTRACE_OBJ_UMODS || dto == NULL)
1882 		return (dt_set_errno(dtp, EINVAL));
1883 
1884 	if ((dmp = dt_module_from_object(dtp, object)) == NULL)
1885 		return (-1); /* dt_errno is set for us */
1886 
1887 	if (dt_module_load(dtp, dmp) == -1)
1888 		return (-1); /* dt_errno is set for us */
1889 
1890 	(void) dt_module_info(dmp, dto);
1891 	return (0);
1892 }
1893