[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);
static void *(*__lttng_ust_plibc_dlmopen)(Lmid_t nsid, const char *filename,
		int flags);
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);
}

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);
}

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 acces 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;
}

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 acces 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;
}

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;
}

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;

}

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 MD	40	static void (__lttng_ust_plibc_dlopen)(const char *filename, int flags);
	41	static void (__lttng_ust_plibc_dlmopen)(Lmid_t nsid, const char *filename,
	42	int flags);
b13d93c2	43	static int (__lttng_ust_plibc_dlclose)(void handle);
b13d93c2 PW	44
b13d93c2 PW	45	static
7b0fdd83	46	void _lttng_ust_dl_libc_dlopen(const char filename, int flags)
b13d93c2 PW	47	{
	48	if (!__lttng_ust_plibc_dlopen) {
	49	__lttng_ust_plibc_dlopen = dlsym(RTLD_NEXT, "dlopen");
8e2aed3f	50	if (!__lttng_ust_plibc_dlopen) {
b13d93c2 PW	51	fprintf(stderr, "%s\n", dlerror());
	52	return NULL;
	53	}
	54	}
7b0fdd83 MD	55	return __lttng_ust_plibc_dlopen(filename, flags);
	56	}
	57
	58	static
	59	void _lttng_ust_dl_libc_dlmopen(Lmid_t nsid, const char filename,
	60	int flags)
	61	{
	62	if (!__lttng_ust_plibc_dlmopen) {
	63	__lttng_ust_plibc_dlmopen = dlsym(RTLD_NEXT, "dlmopen");
	64	if (!__lttng_ust_plibc_dlmopen) {
	65	fprintf(stderr, "%s\n", dlerror());
	66	return NULL;
	67	}
	68	}
	69	return __lttng_ust_plibc_dlmopen(nsid, filename, flags);
b13d93c2 PW	70	}
	71
	72	static
	73	int _lttng_ust_dl_libc_dlclose(void *handle)
	74	{
	75	if (!__lttng_ust_plibc_dlclose) {
	76	__lttng_ust_plibc_dlclose = dlsym(RTLD_NEXT, "dlclose");
8e2aed3f	77	if (!__lttng_ust_plibc_dlclose) {
b13d93c2 PW	78	fprintf(stderr, "%s\n", dlerror());
	79	return -1;
	80	}
	81	}
	82	return __lttng_ust_plibc_dlclose(handle);
	83	}
	84
	85	static
7b0fdd83 MD	86	void lttng_ust_dl_dlopen(void so_base, const char so_name,
7b0fdd83 MD	87	int flags, void *ip)
b13d93c2	88	{
13436238	89	char resolved_path[PATH_MAX];
8e2aed3f AB	90	struct lttng_ust_elf *elf;
8e2aed3f AB	91	uint64_t memsz;
83215d66	92	uint8_t *build_id = NULL;
8e2aed3f	93	size_t build_id_len;
83215d66	94	char *dbg_file = NULL;
8e2aed3f AB	95	uint32_t crc;
	96	int has_build_id = 0, has_debug_link = 0;
	97	int ret;
b13d93c2	98
13436238 PW	99	if (!realpath(so_name, resolved_path)) {
	100	ERR("could not resolve path '%s'", so_name);
	101	return;
b13d93c2	102	}
b13d93c2	103
8e2aed3f AB	104	elf = lttng_ust_elf_create(resolved_path);
	105	if (!elf) {
	106	ERR("could not acces file %s", resolved_path);
13436238	107	return;
b13d93c2	108	}
13436238	109
8e2aed3f AB	110	ret = lttng_ust_elf_get_memsz(elf, &memsz);
	111	if (ret) {
	112	goto end;
	113	}
	114	ret = lttng_ust_elf_get_build_id(
	115	elf, &build_id, &build_id_len, &has_build_id);
	116	if (ret) {
	117	goto end;
	118	}
	119	ret = lttng_ust_elf_get_debug_link(
	120	elf, &dbg_file, &crc, &has_debug_link);
	121	if (ret) {
	122	goto end;
	123	}
	124
6d4658aa	125	tracepoint(lttng_ust_dl, dlopen,
7b0fdd83	126	ip, so_base, resolved_path, flags, memsz,
c5c4fd82	127	has_build_id, has_debug_link);
8e2aed3f AB	128
	129	if (has_build_id) {
	130	tracepoint(lttng_ust_dl, build_id,
	131	ip, so_base, build_id, build_id_len);
8e2aed3f AB	132	}
	133
	134	if (has_debug_link) {
	135	tracepoint(lttng_ust_dl, debug_link,
	136	ip, so_base, dbg_file, crc);
8e2aed3f AB	137	}
	138
	139	end:
83215d66 MD	140	free(dbg_file);
83215d66 MD	141	free(build_id);
8e2aed3f	142	lttng_ust_elf_destroy(elf);
13436238	143	return;
b13d93c2 PW	144	}
b13d93c2 PW	145
7b0fdd83 MD	146	static
	147	void lttng_ust_dl_dlmopen(void so_base, Lmid_t nsid, const char so_name,
	148	int flags, void *ip)
	149	{
	150	char resolved_path[PATH_MAX];
	151	struct lttng_ust_elf *elf;
	152	uint64_t memsz;
	153	uint8_t *build_id = NULL;
	154	size_t build_id_len;
	155	char *dbg_file = NULL;
	156	uint32_t crc;
	157	int has_build_id = 0, has_debug_link = 0;
	158	int ret;
	159
	160	if (!realpath(so_name, resolved_path)) {
	161	ERR("could not resolve path '%s'", so_name);
	162	return;
	163	}
	164
	165	elf = lttng_ust_elf_create(resolved_path);
	166	if (!elf) {
	167	ERR("could not acces file %s", resolved_path);
	168	return;
	169	}
	170
	171	ret = lttng_ust_elf_get_memsz(elf, &memsz);
	172	if (ret) {
	173	goto end;
	174	}
	175	ret = lttng_ust_elf_get_build_id(
	176	elf, &build_id, &build_id_len, &has_build_id);
	177	if (ret) {
	178	goto end;
	179	}
	180	ret = lttng_ust_elf_get_debug_link(
	181	elf, &dbg_file, &crc, &has_debug_link);
	182	if (ret) {
	183	goto end;
	184	}
	185
	186	tracepoint(lttng_ust_dl, dlmopen,
	187	ip, so_base, nsid, resolved_path, flags, memsz,
	188	has_build_id, has_debug_link);
	189
	190	if (has_build_id) {
	191	tracepoint(lttng_ust_dl, build_id,
	192	ip, so_base, build_id, build_id_len);
	193	}
	194
	195	if (has_debug_link) {
	196	tracepoint(lttng_ust_dl, debug_link,
	197	ip, so_base, dbg_file, crc);
	198	}
	199
	200	end:
	201	free(dbg_file);
	202	free(build_id);
	203	lttng_ust_elf_destroy(elf);
	204	return;
	205	}
	206
	207	void dlopen(const char filename, int flags)
b13d93c2	208	{
8e2aed3f AB	209	void *handle;
8e2aed3f AB	210
7b0fdd83	211	handle = _lttng_ust_dl_libc_dlopen(filename, flags);
bd703713	212	if (__tracepoint_ptrs_registered && handle) {
b13d93c2	213	struct link_map *p = NULL;
8e2aed3f AB	214	int ret;
	215
	216	ret = dlinfo(handle, RTLD_DI_LINKMAP, &p);
	217	if (ret != -1 && p != NULL && p->l_addr != 0) {
97c7c238	218	lttng_ust_dl_dlopen((void *) p->l_addr,
7b0fdd83 MD	219	p->l_name, flags, LTTNG_UST_CALLER_IP());
	220	}
	221	}
	222	lttng_ust_dl_update(LTTNG_UST_CALLER_IP());
	223	return handle;
	224	}
	225
	226	void dlmopen(Lmid_t nsid, const char filename, int flags)
	227	{
	228	void *handle;
	229
	230	handle = _lttng_ust_dl_libc_dlmopen(nsid, filename, flags);
	231	if (__tracepoint_ptrs_registered && handle) {
	232	struct link_map *p = NULL;
	233	int ret;
	234
	235	ret = dlinfo(handle, RTLD_DI_LINKMAP, &p);
	236	if (ret != -1 && p != NULL && p->l_addr != 0) {
	237	lttng_ust_dl_dlmopen((void *) p->l_addr,
	238	nsid, p->l_name, flags,
171fcc6f	239	LTTNG_UST_CALLER_IP());
8e2aed3f	240	}
b13d93c2	241	}
97c7c238	242	lttng_ust_dl_update(LTTNG_UST_CALLER_IP());
b13d93c2	243	return handle;
7b0fdd83	244
b13d93c2 PW	245	}
	246
	247	int dlclose(void *handle)
	248	{
97c7c238 MD	249	int ret;
97c7c238 MD	250
e7953e6e	251	if (__tracepoint_ptrs_registered) {
b13d93c2	252	struct link_map *p = NULL;
8e2aed3f AB	253
	254	ret = dlinfo(handle, RTLD_DI_LINKMAP, &p);
	255	if (ret != -1 && p != NULL && p->l_addr != 0) {
	256	tracepoint(lttng_ust_dl, dlclose,
171fcc6f	257	LTTNG_UST_CALLER_IP(),
8e2aed3f AB	258	(void *) p->l_addr);
8e2aed3f AB	259	}
b13d93c2	260	}
97c7c238 MD	261	ret = _lttng_ust_dl_libc_dlclose(handle);
	262	lttng_ust_dl_update(LTTNG_UST_CALLER_IP());
	263	return ret;
b13d93c2	264	}