[lttng-tools.git] / src / common / event-rule / kernel-uprobe.cpp

/*
 * Copyright (C) 2019 Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
 *
 * SPDX-License-Identifier: LGPL-2.1-only
 *
 */

#include <common/credentials.hpp>
#include <common/error.hpp>
#include <common/hashtable/hashtable.hpp>
#include <common/hashtable/utils.hpp>
#include <common/macros.hpp>
#include <common/mi-lttng.hpp>
#include <common/payload-view.hpp>
#include <common/payload.hpp>
#include <common/runas.hpp>

#include <lttng/event-rule/event-rule-internal.hpp>
#include <lttng/event-rule/kernel-uprobe-internal.hpp>
#include <lttng/userspace-probe-internal.hpp>

#define IS_UPROBE_EVENT_RULE(rule) \
	(lttng_event_rule_get_type(rule) == LTTNG_EVENT_RULE_TYPE_KERNEL_UPROBE)

static void lttng_event_rule_kernel_uprobe_destroy(struct lttng_event_rule *rule)
{
	struct lttng_event_rule_kernel_uprobe *uprobe;

	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);

	lttng_userspace_probe_location_destroy(uprobe->location);
	free(uprobe->name);
	free(uprobe);
}

static bool lttng_event_rule_kernel_uprobe_validate(const struct lttng_event_rule *rule)
{
	bool valid = false;
	struct lttng_event_rule_kernel_uprobe *uprobe;

	if (!rule) {
		goto end;
	}

	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);

	/* Required field. */
	if (!uprobe->name) {
		ERR("Invalid uprobe event rule: a pattern must be set.");
		goto end;
	}

	if (!uprobe->location) {
		ERR("Invalid uprobe event rule: a location must be set.");
		goto end;
	}

	valid = true;
end:
	return valid;
}

static int lttng_event_rule_kernel_uprobe_serialize(const struct lttng_event_rule *rule,
						    struct lttng_payload *payload)
{
	int ret;
	size_t name_len, header_offset, size_before_probe;
	struct lttng_event_rule_kernel_uprobe *uprobe;
	struct lttng_event_rule_kernel_uprobe_comm uprobe_comm = {};
	struct lttng_event_rule_kernel_uprobe_comm *header;

	if (!rule || !IS_UPROBE_EVENT_RULE(rule)) {
		ret = -1;
		goto end;
	}

	header_offset = payload->buffer.size;

	DBG("Serializing uprobe event rule.");
	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);

	name_len = strlen(uprobe->name) + 1;

	uprobe_comm.name_len = name_len;

	ret = lttng_dynamic_buffer_append(&payload->buffer, &uprobe_comm, sizeof(uprobe_comm));
	if (ret) {
		goto end;
	}
	ret = lttng_dynamic_buffer_append(&payload->buffer, uprobe->name, name_len);
	if (ret) {
		goto end;
	}

	size_before_probe = payload->buffer.size;

	/* This serialize return the size taken in the buffer. */
	ret = lttng_userspace_probe_location_serialize(uprobe->location, payload);
	if (ret < 0) {
		goto end;
	}

	/* Update the header regarding the probe size. */
	header = (struct lttng_event_rule_kernel_uprobe_comm *) ((char *) payload->buffer.data +
								 header_offset);
	header->location_len = payload->buffer.size - size_before_probe;

	ret = 0;

end:
	return ret;
}

static bool lttng_event_rule_kernel_uprobe_is_equal(const struct lttng_event_rule *_a,
						    const struct lttng_event_rule *_b)
{
	bool is_equal = false;
	struct lttng_event_rule_kernel_uprobe *a, *b;

	a = lttng::utils::container_of(_a, &lttng_event_rule_kernel_uprobe::parent);
	b = lttng::utils::container_of(_b, &lttng_event_rule_kernel_uprobe::parent);

	/* uprobe is invalid if this is not true. */
	LTTNG_ASSERT(a->name);
	LTTNG_ASSERT(b->name);
	if (strcmp(a->name, b->name)) {
		goto end;
	}

	LTTNG_ASSERT(a->location);
	LTTNG_ASSERT(b->location);
	is_equal = lttng_userspace_probe_location_is_equal(a->location, b->location);
end:
	return is_equal;
}

static enum lttng_error_code lttng_event_rule_kernel_uprobe_generate_filter_bytecode(
	struct lttng_event_rule *rule __attribute__((unused)),
	const struct lttng_credentials *creds __attribute__((unused)))
{
	/* Nothing to do. */
	return LTTNG_OK;
}

static const char *lttng_event_rule_kernel_uprobe_get_filter(const struct lttng_event_rule *rule
							     __attribute__((unused)))
{
	/* Unsupported. */
	return NULL;
}

static const struct lttng_bytecode *
lttng_event_rule_kernel_uprobe_get_filter_bytecode(const struct lttng_event_rule *rule
						   __attribute__((unused)))
{
	/* Unsupported. */
	return NULL;
}

static enum lttng_event_rule_generate_exclusions_status
lttng_event_rule_kernel_uprobe_generate_exclusions(const struct lttng_event_rule *rule
						   __attribute__((unused)),
						   struct lttng_event_exclusion **exclusions)
{
	/* Unsupported. */
	*exclusions = NULL;
	return LTTNG_EVENT_RULE_GENERATE_EXCLUSIONS_STATUS_NONE;
}

static unsigned long lttng_event_rule_kernel_uprobe_hash(const struct lttng_event_rule *rule)
{
	unsigned long hash;
	struct lttng_event_rule_kernel_uprobe *urule =
		lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);

	hash = hash_key_ulong((void *) LTTNG_EVENT_RULE_TYPE_KERNEL_UPROBE, lttng_ht_seed);
	hash ^= hash_key_str(urule->name, lttng_ht_seed);
	hash ^= lttng_userspace_probe_location_hash(urule->location);

	return hash;
}

static int userspace_probe_set_location(struct lttng_event_rule_kernel_uprobe *uprobe,
					const struct lttng_userspace_probe_location *location)
{
	int ret;
	struct lttng_userspace_probe_location *location_copy = NULL;

	if (!uprobe || !location || uprobe->location) {
		ret = -1;
		goto end;
	}

	location_copy = lttng_userspace_probe_location_copy(location);
	if (!location_copy) {
		ret = -1;
		goto end;
	}

	uprobe->location = location_copy;
	location_copy = NULL;
	ret = 0;
end:
	lttng_userspace_probe_location_destroy(location_copy);
	return ret;
}

static enum lttng_error_code
lttng_event_rule_kernel_uprobe_mi_serialize(const struct lttng_event_rule *rule,
					    struct mi_writer *writer)
{
	int ret;
	enum lttng_error_code ret_code;
	enum lttng_event_rule_status status;
	const char *event_name = NULL;
	const struct lttng_userspace_probe_location *location = NULL;

	LTTNG_ASSERT(rule);
	LTTNG_ASSERT(writer);
	LTTNG_ASSERT(IS_UPROBE_EVENT_RULE(rule));

	status = lttng_event_rule_kernel_uprobe_get_event_name(rule, &event_name);
	LTTNG_ASSERT(status == LTTNG_EVENT_RULE_STATUS_OK);
	LTTNG_ASSERT(event_name);

	status = lttng_event_rule_kernel_uprobe_get_location(rule, &location);
	LTTNG_ASSERT(status == LTTNG_EVENT_RULE_STATUS_OK);
	LTTNG_ASSERT(location);

	/* Open event rule kernel uprobe element. */
	ret = mi_lttng_writer_open_element(writer, mi_lttng_element_event_rule_kernel_uprobe);
	if (ret) {
		goto mi_error;
	}

	/* Event name. */
	ret = mi_lttng_writer_write_element_string(
		writer, mi_lttng_element_event_rule_event_name, event_name);
	if (ret) {
		goto mi_error;
	}

	/* Probe location. */
	ret_code = lttng_userspace_probe_location_mi_serialize(location, writer);
	if (ret_code != LTTNG_OK) {
		goto end;
	}

	/* Close event rule kernel uprobe element. */
	ret = mi_lttng_writer_close_element(writer);
	if (ret) {
		goto mi_error;
	}

	ret_code = LTTNG_OK;
	goto end;

mi_error:
	ret_code = LTTNG_ERR_MI_IO_FAIL;
end:
	return ret_code;
}

struct lttng_event_rule *
lttng_event_rule_kernel_uprobe_create(const struct lttng_userspace_probe_location *location)
{
	struct lttng_event_rule *rule = NULL;
	struct lttng_event_rule_kernel_uprobe *urule;

	urule = zmalloc<lttng_event_rule_kernel_uprobe>();
	if (!urule) {
		goto end;
	}

	rule = &urule->parent;
	lttng_event_rule_init(&urule->parent, LTTNG_EVENT_RULE_TYPE_KERNEL_UPROBE);
	urule->parent.validate = lttng_event_rule_kernel_uprobe_validate;
	urule->parent.serialize = lttng_event_rule_kernel_uprobe_serialize;
	urule->parent.equal = lttng_event_rule_kernel_uprobe_is_equal;
	urule->parent.destroy = lttng_event_rule_kernel_uprobe_destroy;
	urule->parent.generate_filter_bytecode =
		lttng_event_rule_kernel_uprobe_generate_filter_bytecode;
	urule->parent.get_filter = lttng_event_rule_kernel_uprobe_get_filter;
	urule->parent.get_filter_bytecode = lttng_event_rule_kernel_uprobe_get_filter_bytecode;
	urule->parent.generate_exclusions = lttng_event_rule_kernel_uprobe_generate_exclusions;
	urule->parent.hash = lttng_event_rule_kernel_uprobe_hash;
	urule->parent.mi_serialize = lttng_event_rule_kernel_uprobe_mi_serialize;

	if (userspace_probe_set_location(urule, location)) {
		lttng_event_rule_destroy(rule);
		rule = NULL;
	}

end:
	return rule;
}

ssize_t lttng_event_rule_kernel_uprobe_create_from_payload(struct lttng_payload_view *view,
							   struct lttng_event_rule **_event_rule)
{
	ssize_t ret, offset = 0;
	const struct lttng_event_rule_kernel_uprobe_comm *uprobe_comm;
	const char *name;
	struct lttng_buffer_view current_buffer_view;
	struct lttng_event_rule *rule = NULL;
	struct lttng_userspace_probe_location *location = NULL;
	enum lttng_event_rule_status status;

	if (!_event_rule) {
		ret = -1;
		goto end;
	}

	current_buffer_view =
		lttng_buffer_view_from_view(&view->buffer, offset, sizeof(*uprobe_comm));
	if (!lttng_buffer_view_is_valid(&current_buffer_view)) {
		ERR("Failed to initialize from malformed event rule uprobe: buffer too short to contain header");
		ret = -1;
		goto end;
	}

	uprobe_comm = (typeof(uprobe_comm)) current_buffer_view.data;

	/* Skip to payload. */
	offset += current_buffer_view.size;

	/* Map the name. */
	current_buffer_view =
		lttng_buffer_view_from_view(&view->buffer, offset, uprobe_comm->name_len);
	if (!lttng_buffer_view_is_valid(&current_buffer_view)) {
		ret = -1;
		goto end;
	}

	name = current_buffer_view.data;
	if (!lttng_buffer_view_contains_string(&current_buffer_view, name, uprobe_comm->name_len)) {
		ret = -1;
		goto end;
	}

	/* Skip after the name. */
	offset += uprobe_comm->name_len;

	/* Map the location. */
	{
		struct lttng_payload_view current_payload_view =
			lttng_payload_view_from_view(view, offset, uprobe_comm->location_len);

		if (!lttng_payload_view_is_valid(&current_payload_view)) {
			ERR("Failed to initialize from malformed event rule uprobe: buffer too short to contain location");
			ret = -1;
			goto end;
		}

		ret = lttng_userspace_probe_location_create_from_payload(&current_payload_view,
									 &location);
		if (ret < 0) {
			ret = -1;
			goto end;
		}
	}

	LTTNG_ASSERT(ret == uprobe_comm->location_len);

	/* Skip after the location. */
	offset += uprobe_comm->location_len;

	rule = lttng_event_rule_kernel_uprobe_create(location);
	if (!rule) {
		ERR("Failed to create event rule uprobe.");
		ret = -1;
		goto end;
	}

	status = lttng_event_rule_kernel_uprobe_set_event_name(rule, name);
	if (status != LTTNG_EVENT_RULE_STATUS_OK) {
		ret = -1;
		goto end;
	}

	if (!lttng_event_rule_kernel_uprobe_validate(rule)) {
		ret = -1;
		goto end;
	}

	*_event_rule = rule;
	rule = NULL;
	ret = offset;
end:
	lttng_userspace_probe_location_destroy(location);
	lttng_event_rule_destroy(rule);
	return ret;
}

enum lttng_event_rule_status
lttng_event_rule_kernel_uprobe_get_location(const struct lttng_event_rule *rule,
					    const struct lttng_userspace_probe_location **location)
{
	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;

	if (!rule || !IS_UPROBE_EVENT_RULE(rule) || !location) {
		status = LTTNG_EVENT_RULE_STATUS_INVALID;
		goto end;
	}

	*location = lttng_event_rule_kernel_uprobe_get_location_mutable(rule);
	if (!*location) {
		status = LTTNG_EVENT_RULE_STATUS_UNSET;
		goto end;
	}

end:
	return status;
}

struct lttng_userspace_probe_location *
lttng_event_rule_kernel_uprobe_get_location_mutable(const struct lttng_event_rule *rule)
{
	struct lttng_event_rule_kernel_uprobe *uprobe;

	LTTNG_ASSERT(rule);
	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);

	return uprobe->location;
}

enum lttng_event_rule_status
lttng_event_rule_kernel_uprobe_set_event_name(struct lttng_event_rule *rule, const char *name)
{
	char *name_copy = NULL;
	struct lttng_event_rule_kernel_uprobe *uprobe;
	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;

	if (!rule || !IS_UPROBE_EVENT_RULE(rule) || !name || strlen(name) == 0) {
		status = LTTNG_EVENT_RULE_STATUS_INVALID;
		goto end;
	}

	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);
	name_copy = strdup(name);
	if (!name_copy) {
		status = LTTNG_EVENT_RULE_STATUS_ERROR;
		goto end;
	}

	if (uprobe->name) {
		free(uprobe->name);
	}

	uprobe->name = name_copy;
	name_copy = NULL;
end:
	return status;
}

enum lttng_event_rule_status
lttng_event_rule_kernel_uprobe_get_event_name(const struct lttng_event_rule *rule,
					      const char **name)
{
	struct lttng_event_rule_kernel_uprobe *uprobe;
	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;

	if (!rule || !IS_UPROBE_EVENT_RULE(rule) || !name) {
		status = LTTNG_EVENT_RULE_STATUS_INVALID;
		goto end;
	}

	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);
	if (!uprobe->name) {
		status = LTTNG_EVENT_RULE_STATUS_UNSET;
		goto end;
	}

	*name = uprobe->name;
end:
	return status;
}
Commit	Line	Data
	1	/*
	2	* Copyright (C) 2019 Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
	3	*
	4	* SPDX-License-Identifier: LGPL-2.1-only
	5	*
	6	*/
	7
	8	#include <common/credentials.hpp>
	9	#include <common/error.hpp>
	10	#include <common/hashtable/hashtable.hpp>
	11	#include <common/hashtable/utils.hpp>
	12	#include <common/macros.hpp>
	13	#include <common/mi-lttng.hpp>
	14	#include <common/payload-view.hpp>
	15	#include <common/payload.hpp>
	16	#include <common/runas.hpp>
	17
	18	#include <lttng/event-rule/event-rule-internal.hpp>
	19	#include <lttng/event-rule/kernel-uprobe-internal.hpp>
	20	#include <lttng/userspace-probe-internal.hpp>
	21
	22	#define IS_UPROBE_EVENT_RULE(rule) \
	23	(lttng_event_rule_get_type(rule) == LTTNG_EVENT_RULE_TYPE_KERNEL_UPROBE)
	24
	25	static void lttng_event_rule_kernel_uprobe_destroy(struct lttng_event_rule *rule)
	26	{
	27	struct lttng_event_rule_kernel_uprobe *uprobe;
	28
	29	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);
	30
	31	lttng_userspace_probe_location_destroy(uprobe->location);
	32	free(uprobe->name);
	33	free(uprobe);
	34	}
	35
	36	static bool lttng_event_rule_kernel_uprobe_validate(const struct lttng_event_rule *rule)
	37	{
	38	bool valid = false;
	39	struct lttng_event_rule_kernel_uprobe *uprobe;
	40
	41	if (!rule) {
	42	goto end;
	43	}
	44
	45	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);
	46
	47	/* Required field. */
	48	if (!uprobe->name) {
	49	ERR("Invalid uprobe event rule: a pattern must be set.");
	50	goto end;
	51	}
	52
	53	if (!uprobe->location) {
	54	ERR("Invalid uprobe event rule: a location must be set.");
	55	goto end;
	56	}
	57
	58	valid = true;
	59	end:
	60	return valid;
	61	}
	62
	63	static int lttng_event_rule_kernel_uprobe_serialize(const struct lttng_event_rule *rule,
	64	struct lttng_payload *payload)
	65	{
	66	int ret;
	67	size_t name_len, header_offset, size_before_probe;
	68	struct lttng_event_rule_kernel_uprobe *uprobe;
	69	struct lttng_event_rule_kernel_uprobe_comm uprobe_comm = {};
	70	struct lttng_event_rule_kernel_uprobe_comm *header;
	71
	72	if (!rule \|\| !IS_UPROBE_EVENT_RULE(rule)) {
	73	ret = -1;
	74	goto end;
	75	}
	76
	77	header_offset = payload->buffer.size;
	78
	79	DBG("Serializing uprobe event rule.");
	80	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);
	81
	82	name_len = strlen(uprobe->name) + 1;
	83
	84	uprobe_comm.name_len = name_len;
	85
	86	ret = lttng_dynamic_buffer_append(&payload->buffer, &uprobe_comm, sizeof(uprobe_comm));
	87	if (ret) {
	88	goto end;
	89	}
	90	ret = lttng_dynamic_buffer_append(&payload->buffer, uprobe->name, name_len);
	91	if (ret) {
	92	goto end;
	93	}
	94
	95	size_before_probe = payload->buffer.size;
	96
	97	/* This serialize return the size taken in the buffer. */
	98	ret = lttng_userspace_probe_location_serialize(uprobe->location, payload);
	99	if (ret < 0) {
	100	goto end;
	101	}
	102
	103	/* Update the header regarding the probe size. */
	104	header = (struct lttng_event_rule_kernel_uprobe_comm ) ((char ) payload->buffer.data +
	105	header_offset);
	106	header->location_len = payload->buffer.size - size_before_probe;
	107
	108	ret = 0;
	109
	110	end:
	111	return ret;
	112	}
	113
	114	static bool lttng_event_rule_kernel_uprobe_is_equal(const struct lttng_event_rule *_a,
	115	const struct lttng_event_rule *_b)
	116	{
	117	bool is_equal = false;
	118	struct lttng_event_rule_kernel_uprobe a, b;
	119
	120	a = lttng::utils::container_of(_a, &lttng_event_rule_kernel_uprobe::parent);
	121	b = lttng::utils::container_of(_b, &lttng_event_rule_kernel_uprobe::parent);
	122
	123	/* uprobe is invalid if this is not true. */
	124	LTTNG_ASSERT(a->name);
	125	LTTNG_ASSERT(b->name);
	126	if (strcmp(a->name, b->name)) {
	127	goto end;
	128	}
	129
	130	LTTNG_ASSERT(a->location);
	131	LTTNG_ASSERT(b->location);
	132	is_equal = lttng_userspace_probe_location_is_equal(a->location, b->location);
	133	end:
	134	return is_equal;
	135	}
	136
	137	static enum lttng_error_code lttng_event_rule_kernel_uprobe_generate_filter_bytecode(
	138	struct lttng_event_rule *rule __attribute__((unused)),
	139	const struct lttng_credentials *creds __attribute__((unused)))
	140	{
	141	/* Nothing to do. */
	142	return LTTNG_OK;
	143	}
	144
	145	static const char lttng_event_rule_kernel_uprobe_get_filter(const struct lttng_event_rule rule
	146	__attribute__((unused)))
	147	{
	148	/* Unsupported. */
	149	return NULL;
	150	}
	151
	152	static const struct lttng_bytecode *
	153	lttng_event_rule_kernel_uprobe_get_filter_bytecode(const struct lttng_event_rule *rule
	154	__attribute__((unused)))
	155	{
	156	/* Unsupported. */
	157	return NULL;
	158	}
	159
	160	static enum lttng_event_rule_generate_exclusions_status
	161	lttng_event_rule_kernel_uprobe_generate_exclusions(const struct lttng_event_rule *rule
	162	__attribute__((unused)),
	163	struct lttng_event_exclusion **exclusions)
	164	{
	165	/* Unsupported. */
	166	*exclusions = NULL;
	167	return LTTNG_EVENT_RULE_GENERATE_EXCLUSIONS_STATUS_NONE;
	168	}
	169
	170	static unsigned long lttng_event_rule_kernel_uprobe_hash(const struct lttng_event_rule *rule)
	171	{
	172	unsigned long hash;
	173	struct lttng_event_rule_kernel_uprobe *urule =
	174	lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);
	175
	176	hash = hash_key_ulong((void *) LTTNG_EVENT_RULE_TYPE_KERNEL_UPROBE, lttng_ht_seed);
	177	hash ^= hash_key_str(urule->name, lttng_ht_seed);
	178	hash ^= lttng_userspace_probe_location_hash(urule->location);
	179
	180	return hash;
	181	}
	182
	183	static int userspace_probe_set_location(struct lttng_event_rule_kernel_uprobe *uprobe,
	184	const struct lttng_userspace_probe_location *location)
	185	{
	186	int ret;
	187	struct lttng_userspace_probe_location *location_copy = NULL;
	188
	189	if (!uprobe \|\| !location \|\| uprobe->location) {
	190	ret = -1;
	191	goto end;
	192	}
	193
	194	location_copy = lttng_userspace_probe_location_copy(location);
	195	if (!location_copy) {
	196	ret = -1;
	197	goto end;
	198	}
	199
	200	uprobe->location = location_copy;
	201	location_copy = NULL;
	202	ret = 0;
	203	end:
	204	lttng_userspace_probe_location_destroy(location_copy);
	205	return ret;
	206	}
	207
	208	static enum lttng_error_code
	209	lttng_event_rule_kernel_uprobe_mi_serialize(const struct lttng_event_rule *rule,
	210	struct mi_writer *writer)
	211	{
	212	int ret;
	213	enum lttng_error_code ret_code;
	214	enum lttng_event_rule_status status;
	215	const char *event_name = NULL;
	216	const struct lttng_userspace_probe_location *location = NULL;
	217
	218	LTTNG_ASSERT(rule);
	219	LTTNG_ASSERT(writer);
	220	LTTNG_ASSERT(IS_UPROBE_EVENT_RULE(rule));
	221
	222	status = lttng_event_rule_kernel_uprobe_get_event_name(rule, &event_name);
	223	LTTNG_ASSERT(status == LTTNG_EVENT_RULE_STATUS_OK);
	224	LTTNG_ASSERT(event_name);
	225
	226	status = lttng_event_rule_kernel_uprobe_get_location(rule, &location);
	227	LTTNG_ASSERT(status == LTTNG_EVENT_RULE_STATUS_OK);
	228	LTTNG_ASSERT(location);
	229
	230	/* Open event rule kernel uprobe element. */
	231	ret = mi_lttng_writer_open_element(writer, mi_lttng_element_event_rule_kernel_uprobe);
	232	if (ret) {
	233	goto mi_error;
	234	}
	235
	236	/* Event name. */
	237	ret = mi_lttng_writer_write_element_string(
	238	writer, mi_lttng_element_event_rule_event_name, event_name);
	239	if (ret) {
	240	goto mi_error;
	241	}
	242
	243	/* Probe location. */
	244	ret_code = lttng_userspace_probe_location_mi_serialize(location, writer);
	245	if (ret_code != LTTNG_OK) {
	246	goto end;
	247	}
	248
	249	/* Close event rule kernel uprobe element. */
	250	ret = mi_lttng_writer_close_element(writer);
	251	if (ret) {
	252	goto mi_error;
	253	}
	254
	255	ret_code = LTTNG_OK;
	256	goto end;
	257
	258	mi_error:
	259	ret_code = LTTNG_ERR_MI_IO_FAIL;
	260	end:
	261	return ret_code;
	262	}
	263
	264	struct lttng_event_rule *
	265	lttng_event_rule_kernel_uprobe_create(const struct lttng_userspace_probe_location *location)
	266	{
	267	struct lttng_event_rule *rule = NULL;
	268	struct lttng_event_rule_kernel_uprobe *urule;
	269
	270	urule = zmalloc<lttng_event_rule_kernel_uprobe>();
	271	if (!urule) {
	272	goto end;
	273	}
	274
	275	rule = &urule->parent;
	276	lttng_event_rule_init(&urule->parent, LTTNG_EVENT_RULE_TYPE_KERNEL_UPROBE);
	277	urule->parent.validate = lttng_event_rule_kernel_uprobe_validate;
	278	urule->parent.serialize = lttng_event_rule_kernel_uprobe_serialize;
	279	urule->parent.equal = lttng_event_rule_kernel_uprobe_is_equal;
	280	urule->parent.destroy = lttng_event_rule_kernel_uprobe_destroy;
	281	urule->parent.generate_filter_bytecode =
	282	lttng_event_rule_kernel_uprobe_generate_filter_bytecode;
	283	urule->parent.get_filter = lttng_event_rule_kernel_uprobe_get_filter;
	284	urule->parent.get_filter_bytecode = lttng_event_rule_kernel_uprobe_get_filter_bytecode;
	285	urule->parent.generate_exclusions = lttng_event_rule_kernel_uprobe_generate_exclusions;
	286	urule->parent.hash = lttng_event_rule_kernel_uprobe_hash;
	287	urule->parent.mi_serialize = lttng_event_rule_kernel_uprobe_mi_serialize;
	288
	289	if (userspace_probe_set_location(urule, location)) {
	290	lttng_event_rule_destroy(rule);
	291	rule = NULL;
	292	}
	293
	294	end:
	295	return rule;
	296	}
	297
	298	ssize_t lttng_event_rule_kernel_uprobe_create_from_payload(struct lttng_payload_view *view,
	299	struct lttng_event_rule **_event_rule)
	300	{
	301	ssize_t ret, offset = 0;
	302	const struct lttng_event_rule_kernel_uprobe_comm *uprobe_comm;
	303	const char *name;
	304	struct lttng_buffer_view current_buffer_view;
	305	struct lttng_event_rule *rule = NULL;
	306	struct lttng_userspace_probe_location *location = NULL;
	307	enum lttng_event_rule_status status;
	308
	309	if (!_event_rule) {
	310	ret = -1;
	311	goto end;
	312	}
	313
	314	current_buffer_view =
	315	lttng_buffer_view_from_view(&view->buffer, offset, sizeof(*uprobe_comm));
	316	if (!lttng_buffer_view_is_valid(&current_buffer_view)) {
	317	ERR("Failed to initialize from malformed event rule uprobe: buffer too short to contain header");
	318	ret = -1;
	319	goto end;
	320	}
	321
	322	uprobe_comm = (typeof(uprobe_comm)) current_buffer_view.data;
	323
	324	/* Skip to payload. */
	325	offset += current_buffer_view.size;
	326
	327	/* Map the name. */
	328	current_buffer_view =
	329	lttng_buffer_view_from_view(&view->buffer, offset, uprobe_comm->name_len);
	330	if (!lttng_buffer_view_is_valid(&current_buffer_view)) {
	331	ret = -1;
	332	goto end;
	333	}
	334
	335	name = current_buffer_view.data;
	336	if (!lttng_buffer_view_contains_string(&current_buffer_view, name, uprobe_comm->name_len)) {
	337	ret = -1;
	338	goto end;
	339	}
	340
	341	/* Skip after the name. */
	342	offset += uprobe_comm->name_len;
	343
	344	/* Map the location. */
	345	{
	346	struct lttng_payload_view current_payload_view =
	347	lttng_payload_view_from_view(view, offset, uprobe_comm->location_len);
	348
	349	if (!lttng_payload_view_is_valid(&current_payload_view)) {
	350	ERR("Failed to initialize from malformed event rule uprobe: buffer too short to contain location");
	351	ret = -1;
	352	goto end;
	353	}
	354
	355	ret = lttng_userspace_probe_location_create_from_payload(&current_payload_view,
	356	&location);
	357	if (ret < 0) {
	358	ret = -1;
	359	goto end;
	360	}
	361	}
	362
	363	LTTNG_ASSERT(ret == uprobe_comm->location_len);
	364
	365	/* Skip after the location. */
	366	offset += uprobe_comm->location_len;
	367
	368	rule = lttng_event_rule_kernel_uprobe_create(location);
	369	if (!rule) {
	370	ERR("Failed to create event rule uprobe.");
	371	ret = -1;
	372	goto end;
	373	}
	374
	375	status = lttng_event_rule_kernel_uprobe_set_event_name(rule, name);
	376	if (status != LTTNG_EVENT_RULE_STATUS_OK) {
	377	ret = -1;
	378	goto end;
	379	}
	380
	381	if (!lttng_event_rule_kernel_uprobe_validate(rule)) {
	382	ret = -1;
	383	goto end;
	384	}
	385
	386	*_event_rule = rule;
	387	rule = NULL;
	388	ret = offset;
	389	end:
	390	lttng_userspace_probe_location_destroy(location);
	391	lttng_event_rule_destroy(rule);
	392	return ret;
	393	}
	394
	395	enum lttng_event_rule_status
	396	lttng_event_rule_kernel_uprobe_get_location(const struct lttng_event_rule *rule,
	397	const struct lttng_userspace_probe_location **location)
	398	{
	399	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
	400
	401	if (!rule \|\| !IS_UPROBE_EVENT_RULE(rule) \|\| !location) {
	402	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	403	goto end;
	404	}
	405
	406	*location = lttng_event_rule_kernel_uprobe_get_location_mutable(rule);
	407	if (!*location) {
	408	status = LTTNG_EVENT_RULE_STATUS_UNSET;
	409	goto end;
	410	}
	411
	412	end:
	413	return status;
	414	}
	415
	416	struct lttng_userspace_probe_location *
	417	lttng_event_rule_kernel_uprobe_get_location_mutable(const struct lttng_event_rule *rule)
	418	{
	419	struct lttng_event_rule_kernel_uprobe *uprobe;
	420
	421	LTTNG_ASSERT(rule);
	422	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);
	423
	424	return uprobe->location;
	425	}
	426
	427	enum lttng_event_rule_status
	428	lttng_event_rule_kernel_uprobe_set_event_name(struct lttng_event_rule rule, const char name)
	429	{
	430	char *name_copy = NULL;
	431	struct lttng_event_rule_kernel_uprobe *uprobe;
	432	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
	433
	434	if (!rule \|\| !IS_UPROBE_EVENT_RULE(rule) \|\| !name \|\| strlen(name) == 0) {
	435	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	436	goto end;
	437	}
	438
	439	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);
	440	name_copy = strdup(name);
	441	if (!name_copy) {
	442	status = LTTNG_EVENT_RULE_STATUS_ERROR;
	443	goto end;
	444	}
	445
	446	if (uprobe->name) {
	447	free(uprobe->name);
	448	}
	449
	450	uprobe->name = name_copy;
	451	name_copy = NULL;
	452	end:
	453	return status;
	454	}
	455
	456	enum lttng_event_rule_status
	457	lttng_event_rule_kernel_uprobe_get_event_name(const struct lttng_event_rule *rule,
	458	const char **name)
	459	{
	460	struct lttng_event_rule_kernel_uprobe *uprobe;
	461	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
	462
	463	if (!rule \|\| !IS_UPROBE_EVENT_RULE(rule) \|\| !name) {
	464	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	465	goto end;
	466	}
	467
	468	uprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_uprobe::parent);
	469	if (!uprobe->name) {
	470	status = LTTNG_EVENT_RULE_STATUS_UNSET;
	471	goto end;
	472	}
	473
	474	*name = uprobe->name;
	475	end:
	476	return status;
	477	}