[lttng-ust.git] / liblttng-ust-dl / lttng-ust-dl.c

/*
 * Copyright (C) 2013  Paul Woegerer <paul.woegerer@mentor.com>
 * Copyright (C) 2015  Antoine Busque <abusque@efficios.com>
 * Copyright (C) 2016  Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; version 2.1 of
 * the License.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
 */

#define _GNU_SOURCE
#define _LGPL_SOURCE
#include <limits.h>
#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>

#include <lttng/ust-dlfcn.h>
#include <lttng/ust-elf.h>
#include <lttng/ust-events.h>
#include <helper.h>
#include "usterr-signal-safe.h"

/* Include link.h last else it conflicts with ust-dlfcn. */
#include <link.h>

#define TRACEPOINT_DEFINE
#include "ust_dl.h"

static void *(*__lttng_ust_plibc_dlopen)(const char *filename, int flags);
#ifdef HAVE_DLMOPEN
static void *(*__lttng_ust_plibc_dlmopen)(Lmid_t nsid, const char *filename,
		int flags);
#endif
static int (*__lttng_ust_plibc_dlclose)(void *handle);

static
void *_lttng_ust_dl_libc_dlopen(const char *filename, int flags)
{
	if (!__lttng_ust_plibc_dlopen) {
		__lttng_ust_plibc_dlopen = dlsym(RTLD_NEXT, "dlopen");
		if (!__lttng_ust_plibc_dlopen) {
			fprintf(stderr, "%s\n", dlerror());
			return NULL;
		}
	}
	return __lttng_ust_plibc_dlopen(filename, flags);
}

#ifdef HAVE_DLMOPEN
static
void *_lttng_ust_dl_libc_dlmopen(Lmid_t nsid, const char *filename,
		int flags)
{
	if (!__lttng_ust_plibc_dlmopen) {
		__lttng_ust_plibc_dlmopen = dlsym(RTLD_NEXT, "dlmopen");
		if (!__lttng_ust_plibc_dlmopen) {
			fprintf(stderr, "%s\n", dlerror());
			return NULL;
		}
	}
	return __lttng_ust_plibc_dlmopen(nsid, filename, flags);
}
#endif

static
int _lttng_ust_dl_libc_dlclose(void *handle)
{
	if (!__lttng_ust_plibc_dlclose) {
		__lttng_ust_plibc_dlclose = dlsym(RTLD_NEXT, "dlclose");
		if (!__lttng_ust_plibc_dlclose) {
			fprintf(stderr, "%s\n", dlerror());
			return -1;
		}
	}
	return __lttng_ust_plibc_dlclose(handle);
}

static
void lttng_ust_dl_dlopen(void *so_base, const char *so_name,
		int flags, void *ip)
{
	char resolved_path[PATH_MAX];
	struct lttng_ust_elf *elf;
	uint64_t memsz;
	uint8_t *build_id = NULL;
	size_t build_id_len;
	char *dbg_file = NULL;
	uint32_t crc;
	int has_build_id = 0, has_debug_link = 0;
	int ret;

	if (!realpath(so_name, resolved_path)) {
		ERR("could not resolve path '%s'", so_name);
		return;
	}

	elf = lttng_ust_elf_create(resolved_path);
	if (!elf) {
		ERR("could not access file %s", resolved_path);
		return;
	}

	ret = lttng_ust_elf_get_memsz(elf, &memsz);
	if (ret) {
		goto end;
	}
	ret = lttng_ust_elf_get_build_id(
		elf, &build_id, &build_id_len, &has_build_id);
	if (ret) {
		goto end;
	}
	ret = lttng_ust_elf_get_debug_link(
		elf, &dbg_file, &crc, &has_debug_link);
	if (ret) {
		goto end;
	}

	tracepoint(lttng_ust_dl, dlopen,
		ip, so_base, resolved_path, flags, memsz,
		has_build_id, has_debug_link);

	if (has_build_id) {
		tracepoint(lttng_ust_dl, build_id,
			ip, so_base, build_id, build_id_len);
	}

	if (has_debug_link) {
		tracepoint(lttng_ust_dl, debug_link,
			ip, so_base, dbg_file, crc);
	}

end:
	free(dbg_file);
	free(build_id);
	lttng_ust_elf_destroy(elf);
	return;
}

#ifdef HAVE_DLMOPEN
static
void lttng_ust_dl_dlmopen(void *so_base, Lmid_t nsid, const char *so_name,
		int flags, void *ip)
{
	char resolved_path[PATH_MAX];
	struct lttng_ust_elf *elf;
	uint64_t memsz;
	uint8_t *build_id = NULL;
	size_t build_id_len;
	char *dbg_file = NULL;
	uint32_t crc;
	int has_build_id = 0, has_debug_link = 0;
	int ret;

	if (!realpath(so_name, resolved_path)) {
		ERR("could not resolve path '%s'", so_name);
		return;
	}

	elf = lttng_ust_elf_create(resolved_path);
	if (!elf) {
		ERR("could not access file %s", resolved_path);
		return;
	}

	ret = lttng_ust_elf_get_memsz(elf, &memsz);
	if (ret) {
		goto end;
	}
	ret = lttng_ust_elf_get_build_id(
		elf, &build_id, &build_id_len, &has_build_id);
	if (ret) {
		goto end;
	}
	ret = lttng_ust_elf_get_debug_link(
		elf, &dbg_file, &crc, &has_debug_link);
	if (ret) {
		goto end;
	}

	tracepoint(lttng_ust_dl, dlmopen,
		ip, so_base, nsid, resolved_path, flags, memsz,
		has_build_id, has_debug_link);

	if (has_build_id) {
		tracepoint(lttng_ust_dl, build_id,
			ip, so_base, build_id, build_id_len);
	}

	if (has_debug_link) {
		tracepoint(lttng_ust_dl, debug_link,
			ip, so_base, dbg_file, crc);
	}

end:
	free(dbg_file);
	free(build_id);
	lttng_ust_elf_destroy(elf);
	return;
}
#endif

void *dlopen(const char *filename, int flags)
{
	void *handle;

	handle = _lttng_ust_dl_libc_dlopen(filename, flags);
	if (__tracepoint_ptrs_registered && handle) {
		struct link_map *p = NULL;
		int ret;

		ret = dlinfo(handle, RTLD_DI_LINKMAP, &p);
		if (ret != -1 && p != NULL && p->l_addr != 0) {
			lttng_ust_dl_dlopen((void *) p->l_addr,
				p->l_name, flags, LTTNG_UST_CALLER_IP());
		}
	}
	lttng_ust_dl_update(LTTNG_UST_CALLER_IP());
	return handle;
}

#ifdef HAVE_DLMOPEN
void *dlmopen(Lmid_t nsid, const char *filename, int flags)
{
	void *handle;

	handle = _lttng_ust_dl_libc_dlmopen(nsid, filename, flags);
	if (__tracepoint_ptrs_registered && handle) {
		struct link_map *p = NULL;
		int ret;

		ret = dlinfo(handle, RTLD_DI_LINKMAP, &p);
		if (ret != -1 && p != NULL && p->l_addr != 0) {
			lttng_ust_dl_dlmopen((void *) p->l_addr,
				nsid, p->l_name, flags,
				LTTNG_UST_CALLER_IP());
		}
	}
	lttng_ust_dl_update(LTTNG_UST_CALLER_IP());
	return handle;

}
#endif

int dlclose(void *handle)
{
	int ret;

	if (__tracepoint_ptrs_registered) {
		struct link_map *p = NULL;

		ret = dlinfo(handle, RTLD_DI_LINKMAP, &p);
		if (ret != -1 && p != NULL && p->l_addr != 0) {
			tracepoint(lttng_ust_dl, dlclose,
				LTTNG_UST_CALLER_IP(),
				(void *) p->l_addr);
		}
	}
	ret = _lttng_ust_dl_libc_dlclose(handle);
	lttng_ust_dl_update(LTTNG_UST_CALLER_IP());
	return ret;
}
Commit	Line	Data
b13d93c2 PW	1	/*
b13d93c2 PW	2	* Copyright (C) 2013 Paul Woegerer <paul.woegerer@mentor.com>
8e2aed3f	3	* Copyright (C) 2015 Antoine Busque <abusque@efficios.com>
97c7c238	4	* Copyright (C) 2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
b13d93c2 PW	5	*
	6	* This library is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU Lesser General Public
	8	* License as published by the Free Software Foundation; version 2.1 of
	9	* the License.
	10	*
	11	* This library is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* Lesser General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU Lesser General Public
	17	* License along with this library; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	19	*/
	20
	21	#define _GNU_SOURCE
1ddceb36	22	#define _LGPL_SOURCE
13436238	23	#include <limits.h>
8e2aed3f	24	#include <stdio.h>
13436238	25	#include <sys/types.h>
8e2aed3f AB	26	#include <unistd.h>
	27
	28	#include <lttng/ust-dlfcn.h>
	29	#include <lttng/ust-elf.h>
97c7c238	30	#include <lttng/ust-events.h>
171fcc6f	31	#include <helper.h>
eb2b066f	32	#include "usterr-signal-safe.h"
b13d93c2	33
8e2aed3f AB	34	/* Include link.h last else it conflicts with ust-dlfcn. */
8e2aed3f AB	35	#include <link.h>
b13d93c2	36
13436238	37	#define TRACEPOINT_DEFINE
6d4658aa	38	#include "ust_dl.h"
13436238	39
7b0fdd83	40	static void (__lttng_ust_plibc_dlopen)(const char *filename, int flags);
42330adc	41	#ifdef HAVE_DLMOPEN
7b0fdd83 MD	42	static void (__lttng_ust_plibc_dlmopen)(Lmid_t nsid, const char *filename,
7b0fdd83 MD	43	int flags);
42330adc	44	#endif
b13d93c2	45	static int (__lttng_ust_plibc_dlclose)(void handle);
b13d93c2 PW	46
b13d93c2 PW	47	static
7b0fdd83	48	void _lttng_ust_dl_libc_dlopen(const char filename, int flags)
b13d93c2 PW	49	{
	50	if (!__lttng_ust_plibc_dlopen) {
	51	__lttng_ust_plibc_dlopen = dlsym(RTLD_NEXT, "dlopen");
8e2aed3f	52	if (!__lttng_ust_plibc_dlopen) {
b13d93c2 PW	53	fprintf(stderr, "%s\n", dlerror());
	54	return NULL;
	55	}
	56	}
7b0fdd83 MD	57	return __lttng_ust_plibc_dlopen(filename, flags);
	58	}
	59
42330adc	60	#ifdef HAVE_DLMOPEN
7b0fdd83 MD	61	static
	62	void _lttng_ust_dl_libc_dlmopen(Lmid_t nsid, const char filename,
	63	int flags)
	64	{
	65	if (!__lttng_ust_plibc_dlmopen) {
	66	__lttng_ust_plibc_dlmopen = dlsym(RTLD_NEXT, "dlmopen");
	67	if (!__lttng_ust_plibc_dlmopen) {
	68	fprintf(stderr, "%s\n", dlerror());
	69	return NULL;
	70	}
	71	}
	72	return __lttng_ust_plibc_dlmopen(nsid, filename, flags);
b13d93c2	73	}
42330adc	74	#endif
b13d93c2 PW	75
	76	static
	77	int _lttng_ust_dl_libc_dlclose(void *handle)
	78	{
	79	if (!__lttng_ust_plibc_dlclose) {
	80	__lttng_ust_plibc_dlclose = dlsym(RTLD_NEXT, "dlclose");
8e2aed3f	81	if (!__lttng_ust_plibc_dlclose) {
b13d93c2 PW	82	fprintf(stderr, "%s\n", dlerror());
	83	return -1;
	84	}
	85	}
	86	return __lttng_ust_plibc_dlclose(handle);
	87	}
	88
	89	static
7b0fdd83 MD	90	void lttng_ust_dl_dlopen(void so_base, const char so_name,
7b0fdd83 MD	91	int flags, void *ip)
b13d93c2	92	{
13436238	93	char resolved_path[PATH_MAX];
8e2aed3f AB	94	struct lttng_ust_elf *elf;
8e2aed3f AB	95	uint64_t memsz;
83215d66	96	uint8_t *build_id = NULL;
8e2aed3f	97	size_t build_id_len;
83215d66	98	char *dbg_file = NULL;
8e2aed3f AB	99	uint32_t crc;
	100	int has_build_id = 0, has_debug_link = 0;
	101	int ret;
b13d93c2	102
13436238 PW	103	if (!realpath(so_name, resolved_path)) {
	104	ERR("could not resolve path '%s'", so_name);
	105	return;
b13d93c2	106	}
b13d93c2	107
8e2aed3f AB	108	elf = lttng_ust_elf_create(resolved_path);
8e2aed3f AB	109	if (!elf) {
09026ccf	110	ERR("could not access file %s", resolved_path);
13436238	111	return;
b13d93c2	112	}
13436238	113
8e2aed3f AB	114	ret = lttng_ust_elf_get_memsz(elf, &memsz);
	115	if (ret) {
	116	goto end;
	117	}
	118	ret = lttng_ust_elf_get_build_id(
	119	elf, &build_id, &build_id_len, &has_build_id);
	120	if (ret) {
	121	goto end;
	122	}
	123	ret = lttng_ust_elf_get_debug_link(
	124	elf, &dbg_file, &crc, &has_debug_link);
	125	if (ret) {
	126	goto end;
	127	}
	128
6d4658aa	129	tracepoint(lttng_ust_dl, dlopen,
7b0fdd83	130	ip, so_base, resolved_path, flags, memsz,
c5c4fd82	131	has_build_id, has_debug_link);
8e2aed3f AB	132
	133	if (has_build_id) {
	134	tracepoint(lttng_ust_dl, build_id,
	135	ip, so_base, build_id, build_id_len);
8e2aed3f AB	136	}
	137
	138	if (has_debug_link) {
	139	tracepoint(lttng_ust_dl, debug_link,
	140	ip, so_base, dbg_file, crc);
8e2aed3f AB	141	}
	142
	143	end:
83215d66 MD	144	free(dbg_file);
83215d66 MD	145	free(build_id);
8e2aed3f	146	lttng_ust_elf_destroy(elf);
13436238	147	return;
b13d93c2 PW	148	}
b13d93c2 PW	149
42330adc	150	#ifdef HAVE_DLMOPEN
7b0fdd83 MD	151	static
	152	void lttng_ust_dl_dlmopen(void so_base, Lmid_t nsid, const char so_name,
	153	int flags, void *ip)
	154	{
	155	char resolved_path[PATH_MAX];
	156	struct lttng_ust_elf *elf;
	157	uint64_t memsz;
	158	uint8_t *build_id = NULL;
	159	size_t build_id_len;
	160	char *dbg_file = NULL;
	161	uint32_t crc;
	162	int has_build_id = 0, has_debug_link = 0;
	163	int ret;
	164
	165	if (!realpath(so_name, resolved_path)) {
	166	ERR("could not resolve path '%s'", so_name);
	167	return;
	168	}
	169
	170	elf = lttng_ust_elf_create(resolved_path);
	171	if (!elf) {
09026ccf	172	ERR("could not access file %s", resolved_path);
7b0fdd83 MD	173	return;
	174	}
	175
	176	ret = lttng_ust_elf_get_memsz(elf, &memsz);
	177	if (ret) {
	178	goto end;
	179	}
	180	ret = lttng_ust_elf_get_build_id(
	181	elf, &build_id, &build_id_len, &has_build_id);
	182	if (ret) {
	183	goto end;
	184	}
	185	ret = lttng_ust_elf_get_debug_link(
	186	elf, &dbg_file, &crc, &has_debug_link);
	187	if (ret) {
	188	goto end;
	189	}
	190
	191	tracepoint(lttng_ust_dl, dlmopen,
	192	ip, so_base, nsid, resolved_path, flags, memsz,
	193	has_build_id, has_debug_link);
	194
	195	if (has_build_id) {
	196	tracepoint(lttng_ust_dl, build_id,
	197	ip, so_base, build_id, build_id_len);
	198	}
	199
	200	if (has_debug_link) {
	201	tracepoint(lttng_ust_dl, debug_link,
	202	ip, so_base, dbg_file, crc);
	203	}
	204
	205	end:
	206	free(dbg_file);
	207	free(build_id);
	208	lttng_ust_elf_destroy(elf);
	209	return;
	210	}
42330adc	211	#endif
7b0fdd83 MD	212
7b0fdd83 MD	213	void dlopen(const char filename, int flags)
b13d93c2	214	{
8e2aed3f AB	215	void *handle;
8e2aed3f AB	216
7b0fdd83	217	handle = _lttng_ust_dl_libc_dlopen(filename, flags);
bd703713	218	if (__tracepoint_ptrs_registered && handle) {
b13d93c2	219	struct link_map *p = NULL;
8e2aed3f AB	220	int ret;
	221
	222	ret = dlinfo(handle, RTLD_DI_LINKMAP, &p);
	223	if (ret != -1 && p != NULL && p->l_addr != 0) {
97c7c238	224	lttng_ust_dl_dlopen((void *) p->l_addr,
7b0fdd83 MD	225	p->l_name, flags, LTTNG_UST_CALLER_IP());
	226	}
	227	}
	228	lttng_ust_dl_update(LTTNG_UST_CALLER_IP());
	229	return handle;
	230	}
	231
42330adc	232	#ifdef HAVE_DLMOPEN
7b0fdd83 MD	233	void dlmopen(Lmid_t nsid, const char filename, int flags)
	234	{
	235	void *handle;
	236
	237	handle = _lttng_ust_dl_libc_dlmopen(nsid, filename, flags);
	238	if (__tracepoint_ptrs_registered && handle) {
	239	struct link_map *p = NULL;
	240	int ret;
	241
	242	ret = dlinfo(handle, RTLD_DI_LINKMAP, &p);
	243	if (ret != -1 && p != NULL && p->l_addr != 0) {
	244	lttng_ust_dl_dlmopen((void *) p->l_addr,
	245	nsid, p->l_name, flags,
171fcc6f	246	LTTNG_UST_CALLER_IP());
8e2aed3f	247	}
b13d93c2	248	}
97c7c238	249	lttng_ust_dl_update(LTTNG_UST_CALLER_IP());
b13d93c2	250	return handle;
7b0fdd83	251
b13d93c2	252	}
42330adc	253	#endif
b13d93c2 PW	254
	255	int dlclose(void *handle)
	256	{
97c7c238 MD	257	int ret;
97c7c238 MD	258
e7953e6e	259	if (__tracepoint_ptrs_registered) {
b13d93c2	260	struct link_map *p = NULL;
8e2aed3f AB	261
	262	ret = dlinfo(handle, RTLD_DI_LINKMAP, &p);
	263	if (ret != -1 && p != NULL && p->l_addr != 0) {
	264	tracepoint(lttng_ust_dl, dlclose,
171fcc6f	265	LTTNG_UST_CALLER_IP(),
8e2aed3f AB	266	(void *) p->l_addr);
8e2aed3f AB	267	}
b13d93c2	268	}
97c7c238 MD	269	ret = _lttng_ust_dl_libc_dlclose(handle);
	270	lttng_ust_dl_update(LTTNG_UST_CALLER_IP());
	271	return ret;
b13d93c2	272	}