[lttng-tools.git] / src / common / event-rule / kernel-kprobe.c

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

#include <common/credentials.h>
#include <common/error.h>
#include <common/hashtable/hashtable.h>
#include <common/hashtable/utils.h>
#include <common/macros.h>
#include <common/mi-lttng.h>
#include <common/payload-view.h>
#include <common/payload.h>
#include <common/runas.h>
#include <ctype.h>
#include <lttng/constant.h>
#include <lttng/event-rule/event-rule-internal.h>
#include <lttng/event-rule/event-rule.h>
#include <lttng/event-rule/kernel-kprobe-internal.h>
#include <lttng/kernel-probe-internal.h>
#include <lttng/kernel-probe.h>
#include <stdio.h>

#define IS_KPROBE_EVENT_RULE(rule) \
	(lttng_event_rule_get_type(rule) == LTTNG_EVENT_RULE_TYPE_KERNEL_KPROBE)

#if (LTTNG_SYMBOL_NAME_LEN == 256)
#define LTTNG_SYMBOL_NAME_LEN_SCANF_IS_A_BROKEN_API "255"
#endif

static void lttng_event_rule_kernel_kprobe_destroy(struct lttng_event_rule *rule)
{
	struct lttng_event_rule_kernel_kprobe *kprobe;

	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);

	lttng_kernel_probe_location_destroy(kprobe->location);
	free(kprobe->name);
	free(kprobe);
}

static bool lttng_event_rule_kernel_kprobe_validate(
		const struct lttng_event_rule *rule)
{
	bool valid = false;
	struct lttng_event_rule_kernel_kprobe *kprobe;

	if (!rule) {
		goto end;
	}

	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);

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

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

	valid = true;
end:
	return valid;
}

static int lttng_event_rule_kernel_kprobe_serialize(
		const struct lttng_event_rule *rule,
		struct lttng_payload *payload)
{
	int ret;
	size_t name_len, header_offset, size_before_location;
	struct lttng_event_rule_kernel_kprobe *kprobe;
	struct lttng_event_rule_kernel_kprobe_comm kprobe_comm;
	struct lttng_event_rule_kernel_kprobe_comm *header;

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

	header_offset = payload->buffer.size;

	DBG("Serializing kprobe event rule.");
	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);

	name_len = strlen(kprobe->name) + 1;
	kprobe_comm.name_len = name_len;

	ret = lttng_dynamic_buffer_append(
			&payload->buffer, &kprobe_comm, sizeof(kprobe_comm));
	if (ret) {
		goto end;
	}

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

	size_before_location = payload->buffer.size;

	ret = lttng_kernel_probe_location_serialize(kprobe->location, payload);
	if (ret < 0) {
		goto end;
	}

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

	ret = 0;

end:
	return ret;
}

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

	a = container_of(_a, struct lttng_event_rule_kernel_kprobe, parent);
	b = container_of(_b, struct lttng_event_rule_kernel_kprobe, parent);

	/* Quick checks */
	if (!!a->name != !!b->name) {
		goto end;
	}

	/* Long check */
	LTTNG_ASSERT(a->name);
	LTTNG_ASSERT(b->name);
	if (strcmp(a->name, b->name)) {
		goto end;
	}

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

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

static const char *lttng_event_rule_kernel_kprobe_get_filter(
		const struct lttng_event_rule *rule)
{
	/* Not supported. */
	return NULL;
}

static const struct lttng_bytecode *
lttng_event_rule_kernel_kprobe_get_filter_bytecode(const struct lttng_event_rule *rule)
{
	/* Not supported. */
	return NULL;
}

static enum lttng_event_rule_generate_exclusions_status
lttng_event_rule_kernel_kprobe_generate_exclusions(const struct lttng_event_rule *rule,
		struct lttng_event_exclusion **exclusions)
{
	/* Not supported. */
	*exclusions = NULL;
	return LTTNG_EVENT_RULE_GENERATE_EXCLUSIONS_STATUS_NONE;
}

static unsigned long
lttng_event_rule_kernel_kprobe_hash(
		const struct lttng_event_rule *rule)
{
	unsigned long hash;
	struct lttng_event_rule_kernel_kprobe *krule =
			container_of(rule, typeof(*krule), parent);

	hash = hash_key_ulong((void *) LTTNG_EVENT_RULE_TYPE_KERNEL_KPROBE,
			lttng_ht_seed);
	hash ^= hash_key_str(krule->name, lttng_ht_seed);
	hash ^= lttng_kernel_probe_location_hash(krule->location);

	return hash;
}

static
int kernel_probe_set_location(
		struct lttng_event_rule_kernel_kprobe *kprobe,
		const struct lttng_kernel_probe_location *location)
{
	int ret;
	struct lttng_kernel_probe_location *location_copy = NULL;

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

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

	kprobe->location = location_copy;
	location_copy = NULL;
	ret = 0;
end:
	lttng_kernel_probe_location_destroy(location_copy);
	return ret;
}

static
enum lttng_error_code lttng_event_rule_kernel_kprobe_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_kernel_probe_location *location = NULL;

	LTTNG_ASSERT(rule);
	LTTNG_ASSERT(writer);
	LTTNG_ASSERT(IS_KPROBE_EVENT_RULE(rule));

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

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

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

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

	/* Close event rule kernel kprobe 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_kprobe_create(
		const struct lttng_kernel_probe_location *location)
{
	struct lttng_event_rule *rule = NULL;
	struct lttng_event_rule_kernel_kprobe *krule;

	krule = zmalloc(sizeof(struct lttng_event_rule_kernel_kprobe));
	if (!krule) {
		goto end;
	}

	rule = &krule->parent;
	lttng_event_rule_init(&krule->parent, LTTNG_EVENT_RULE_TYPE_KERNEL_KPROBE);
	krule->parent.validate = lttng_event_rule_kernel_kprobe_validate;
	krule->parent.serialize = lttng_event_rule_kernel_kprobe_serialize;
	krule->parent.equal = lttng_event_rule_kernel_kprobe_is_equal;
	krule->parent.destroy = lttng_event_rule_kernel_kprobe_destroy;
	krule->parent.generate_filter_bytecode =
			lttng_event_rule_kernel_kprobe_generate_filter_bytecode;
	krule->parent.get_filter = lttng_event_rule_kernel_kprobe_get_filter;
	krule->parent.get_filter_bytecode =
			lttng_event_rule_kernel_kprobe_get_filter_bytecode;
	krule->parent.generate_exclusions =
			lttng_event_rule_kernel_kprobe_generate_exclusions;
	krule->parent.hash = lttng_event_rule_kernel_kprobe_hash;
	krule->parent.mi_serialize = lttng_event_rule_kernel_kprobe_mi_serialize;

	if (kernel_probe_set_location(krule, location)) {
		lttng_event_rule_destroy(rule);
		rule = NULL;
	}

end:
	return rule;
}

ssize_t lttng_event_rule_kernel_kprobe_create_from_payload(
		struct lttng_payload_view *view,
		struct lttng_event_rule **_event_rule)
{
	ssize_t ret, offset = 0;
	enum lttng_event_rule_status status;
	const struct lttng_event_rule_kernel_kprobe_comm *kprobe_comm;
	const char *name;
	struct lttng_buffer_view current_buffer_view;
	struct lttng_event_rule *rule = NULL;
	struct lttng_kernel_probe_location *location = NULL;

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

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

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

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

	{
		/* Map the name. */
		struct lttng_payload_view current_payload_view =
				lttng_payload_view_from_view(view, offset,
						kprobe_comm->name_len);

		if (!lttng_payload_view_is_valid(&current_payload_view)) {
			ret = -1;
			goto end;
		}

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

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

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

		if (!lttng_payload_view_is_valid(&current_payload_view)) {
			ret = -1;
			goto end;
		}

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

	if (ret != kprobe_comm->location_len) {
		ret = -1;
		goto end;
	}

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

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

	status = lttng_event_rule_kernel_kprobe_set_event_name(rule, name);
	if (status != LTTNG_EVENT_RULE_STATUS_OK) {
		ERR("Failed to set event rule kprobe name.");
		ret = -1;
		goto end;
	}

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

enum lttng_event_rule_status lttng_event_rule_kernel_kprobe_get_location(
		const struct lttng_event_rule *rule,
		const struct lttng_kernel_probe_location **location)
{
	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
	struct lttng_event_rule_kernel_kprobe *kprobe;

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

	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
	*location = kprobe->location;

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

end:
	return status;
}

enum lttng_event_rule_status lttng_event_rule_kernel_kprobe_set_event_name(
		struct lttng_event_rule *rule, const char *name)
{
	char *name_copy = NULL;
	struct lttng_event_rule_kernel_kprobe *kprobe;
	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;

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

	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
	name_copy = strdup(name);
	if (!name_copy) {
		status = LTTNG_EVENT_RULE_STATUS_ERROR;
		goto end;
	}

	free(kprobe->name);

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

enum lttng_event_rule_status lttng_event_rule_kernel_kprobe_get_event_name(
		const struct lttng_event_rule *rule, const char **name)
{
	struct lttng_event_rule_kernel_kprobe *kprobe;
	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;

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

	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
	if (!kprobe->name) {
		status = LTTNG_EVENT_RULE_STATUS_UNSET;
		goto end;
	}

	*name = kprobe->name;
end:
	return status;
}
Commit	Line	Data
077192fd JR	1	/*
	2	* Copyright (C) 2019 Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
	3	*
	4	* SPDX-License-Identifier: LGPL-2.1-only
	5	*
	6	*/
	7
58daac01	8	#include <common/credentials.h>
077192fd	9	#include <common/error.h>
6a751b95 JR	10	#include <common/hashtable/hashtable.h>
6a751b95 JR	11	#include <common/hashtable/utils.h>
077192fd	12	#include <common/macros.h>
6a751b95	13	#include <common/mi-lttng.h>
077192fd	14	#include <common/payload-view.h>
6a751b95	15	#include <common/payload.h>
077192fd JR	16	#include <common/runas.h>
	17	#include <ctype.h>
	18	#include <lttng/constant.h>
	19	#include <lttng/event-rule/event-rule-internal.h>
6a751b95	20	#include <lttng/event-rule/event-rule.h>
85522de5	21	#include <lttng/event-rule/kernel-kprobe-internal.h>
077192fd	22	#include <lttng/kernel-probe-internal.h>
6a751b95	23	#include <lttng/kernel-probe.h>
077192fd JR	24	#include <stdio.h>
	25
	26	#define IS_KPROBE_EVENT_RULE(rule) \
85522de5	27	(lttng_event_rule_get_type(rule) == LTTNG_EVENT_RULE_TYPE_KERNEL_KPROBE)
077192fd JR	28
	29	#if (LTTNG_SYMBOL_NAME_LEN == 256)
	30	#define LTTNG_SYMBOL_NAME_LEN_SCANF_IS_A_BROKEN_API "255"
	31	#endif
	32
85522de5	33	static void lttng_event_rule_kernel_kprobe_destroy(struct lttng_event_rule *rule)
077192fd	34	{
85522de5	35	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd	36
85522de5	37	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
077192fd JR	38
	39	lttng_kernel_probe_location_destroy(kprobe->location);
	40	free(kprobe->name);
	41	free(kprobe);
	42	}
	43
85522de5	44	static bool lttng_event_rule_kernel_kprobe_validate(
077192fd JR	45	const struct lttng_event_rule *rule)
	46	{
	47	bool valid = false;
85522de5	48	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd JR	49
	50	if (!rule) {
	51	goto end;
	52	}
	53
85522de5	54	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
077192fd JR	55
	56	/* Required field. */
	57	if (!kprobe->name) {
	58	ERR("Invalid name event rule: a name must be set.");
	59	goto end;
	60	}
	61
	62	/* Required field. */
	63	if(!kprobe->location) {
	64	ERR("Invalid name event rule: a location must be set.");
	65	goto end;
	66	}
	67
	68	valid = true;
	69	end:
	70	return valid;
	71	}
	72
85522de5	73	static int lttng_event_rule_kernel_kprobe_serialize(
077192fd JR	74	const struct lttng_event_rule *rule,
	75	struct lttng_payload *payload)
	76	{
	77	int ret;
	78	size_t name_len, header_offset, size_before_location;
85522de5 JR	79	struct lttng_event_rule_kernel_kprobe *kprobe;
	80	struct lttng_event_rule_kernel_kprobe_comm kprobe_comm;
	81	struct lttng_event_rule_kernel_kprobe_comm *header;
077192fd JR	82
	83	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule)) {
	84	ret = -1;
	85	goto end;
	86	}
	87
	88	header_offset = payload->buffer.size;
	89
	90	DBG("Serializing kprobe event rule.");
85522de5	91	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
077192fd JR	92
	93	name_len = strlen(kprobe->name) + 1;
	94	kprobe_comm.name_len = name_len;
	95
	96	ret = lttng_dynamic_buffer_append(
	97	&payload->buffer, &kprobe_comm, sizeof(kprobe_comm));
	98	if (ret) {
	99	goto end;
	100	}
	101
	102	ret = lttng_dynamic_buffer_append(&payload->buffer, kprobe->name, name_len);
	103	if (ret) {
	104	goto end;
	105	}
	106
	107	size_before_location = payload->buffer.size;
	108
	109	ret = lttng_kernel_probe_location_serialize(kprobe->location, payload);
	110	if (ret < 0) {
	111	goto end;
	112	}
	113
	114	/* Update the header regarding the probe size. */
85522de5	115	header = (struct lttng_event_rule_kernel_kprobe_comm*) (
077192fd JR	116	(char *) payload->buffer.data + header_offset);
	117	header->location_len = payload->buffer.size - size_before_location;
	118
	119	ret = 0;
	120
	121	end:
	122	return ret;
	123	}
	124
85522de5	125	static bool lttng_event_rule_kernel_kprobe_is_equal(const struct lttng_event_rule *_a,
077192fd JR	126	const struct lttng_event_rule *_b)
	127	{
	128	bool is_equal = false;
85522de5	129	struct lttng_event_rule_kernel_kprobe a, b;
077192fd	130
85522de5 JR	131	a = container_of(_a, struct lttng_event_rule_kernel_kprobe, parent);
85522de5 JR	132	b = container_of(_b, struct lttng_event_rule_kernel_kprobe, parent);
077192fd JR	133
	134	/* Quick checks */
	135	if (!!a->name != !!b->name) {
	136	goto end;
	137	}
	138
	139	/* Long check */
a0377dfe FD	140	LTTNG_ASSERT(a->name);
a0377dfe FD	141	LTTNG_ASSERT(b->name);
077192fd JR	142	if (strcmp(a->name, b->name)) {
	143	goto end;
	144	}
	145
	146	is_equal = lttng_kernel_probe_location_is_equal(
	147	a->location, b->location);
	148	end:
	149	return is_equal;
	150	}
	151
85522de5	152	static enum lttng_error_code lttng_event_rule_kernel_kprobe_generate_filter_bytecode(
58daac01 JR	153	struct lttng_event_rule *rule,
58daac01 JR	154	const struct lttng_credentials *creds)
077192fd JR	155	{
	156	/* Nothing to do. */
	157	return LTTNG_OK;
	158	}
	159
85522de5	160	static const char *lttng_event_rule_kernel_kprobe_get_filter(
077192fd JR	161	const struct lttng_event_rule *rule)
	162	{
	163	/* Not supported. */
	164	return NULL;
	165	}
	166
2b00d462	167	static const struct lttng_bytecode *
85522de5	168	lttng_event_rule_kernel_kprobe_get_filter_bytecode(const struct lttng_event_rule *rule)
077192fd JR	169	{
	170	/* Not supported. */
	171	return NULL;
	172	}
	173
993578ff	174	static enum lttng_event_rule_generate_exclusions_status
85522de5	175	lttng_event_rule_kernel_kprobe_generate_exclusions(const struct lttng_event_rule *rule,
993578ff	176	struct lttng_event_exclusion **exclusions)
077192fd JR	177	{
077192fd JR	178	/* Not supported. */
993578ff JR	179	*exclusions = NULL;
993578ff JR	180	return LTTNG_EVENT_RULE_GENERATE_EXCLUSIONS_STATUS_NONE;
077192fd JR	181	}
077192fd JR	182
959e3c66	183	static unsigned long
85522de5	184	lttng_event_rule_kernel_kprobe_hash(
959e3c66 JR	185	const struct lttng_event_rule *rule)
	186	{
	187	unsigned long hash;
85522de5	188	struct lttng_event_rule_kernel_kprobe *krule =
959e3c66 JR	189	container_of(rule, typeof(*krule), parent);
959e3c66 JR	190
85522de5	191	hash = hash_key_ulong((void *) LTTNG_EVENT_RULE_TYPE_KERNEL_KPROBE,
959e3c66 JR	192	lttng_ht_seed);
	193	hash ^= hash_key_str(krule->name, lttng_ht_seed);
	194	hash ^= lttng_kernel_probe_location_hash(krule->location);
	195
	196	return hash;
	197	}
	198
602a6d40 JR	199	static
602a6d40 JR	200	int kernel_probe_set_location(
85522de5	201	struct lttng_event_rule_kernel_kprobe *kprobe,
602a6d40 JR	202	const struct lttng_kernel_probe_location *location)
	203	{
	204	int ret;
	205	struct lttng_kernel_probe_location *location_copy = NULL;
	206
	207	if (!kprobe \|\| !location \|\| kprobe->location) {
	208	ret = -1;
	209	goto end;
	210	}
	211
	212	location_copy = lttng_kernel_probe_location_copy(location);
	213	if (!location_copy) {
	214	ret = -1;
	215	goto end;
	216	}
	217
	218	kprobe->location = location_copy;
	219	location_copy = NULL;
	220	ret = 0;
	221	end:
	222	lttng_kernel_probe_location_destroy(location_copy);
	223	return ret;
	224	}
	225
6a751b95 JR	226	static
	227	enum lttng_error_code lttng_event_rule_kernel_kprobe_mi_serialize(
	228	const struct lttng_event_rule rule, struct mi_writer writer)
	229	{
	230	int ret;
	231	enum lttng_error_code ret_code;
	232	enum lttng_event_rule_status status;
	233	const char *event_name = NULL;
	234	const struct lttng_kernel_probe_location *location = NULL;
	235
a0377dfe FD	236	LTTNG_ASSERT(rule);
	237	LTTNG_ASSERT(writer);
	238	LTTNG_ASSERT(IS_KPROBE_EVENT_RULE(rule));
6a751b95 JR	239
	240	status = lttng_event_rule_kernel_kprobe_get_event_name(
	241	rule, &event_name);
a0377dfe FD	242	LTTNG_ASSERT(status == LTTNG_EVENT_RULE_STATUS_OK);
a0377dfe FD	243	LTTNG_ASSERT(event_name);
6a751b95 JR	244
6a751b95 JR	245	status = lttng_event_rule_kernel_kprobe_get_location(rule, &location);
a0377dfe FD	246	LTTNG_ASSERT(status == LTTNG_EVENT_RULE_STATUS_OK);
a0377dfe FD	247	LTTNG_ASSERT(location);
6a751b95 JR	248
	249	/* Open event rule kernel kprobe element. */
	250	ret = mi_lttng_writer_open_element(
	251	writer, mi_lttng_element_event_rule_kernel_kprobe);
	252	if (ret) {
	253	goto mi_error;
	254	}
	255
	256	/* Name. */
	257	ret = mi_lttng_writer_write_element_string(writer,
	258	mi_lttng_element_event_rule_event_name, event_name);
	259	if (ret) {
	260	goto mi_error;
	261	}
	262
	263	/* Probe location. */
	264	ret_code = lttng_kernel_probe_location_mi_serialize(location, writer);
	265	if (ret_code != LTTNG_OK) {
	266	goto end;
	267	}
	268
	269	/* Close event rule kernel kprobe element. */
	270	ret = mi_lttng_writer_close_element(writer);
	271	if (ret) {
	272	goto mi_error;
	273	}
	274
	275	ret_code = LTTNG_OK;
	276	goto end;
	277
	278	mi_error:
	279	ret_code = LTTNG_ERR_MI_IO_FAIL;
	280	end:
	281	return ret_code;
	282	}
	283
85522de5	284	struct lttng_event_rule *lttng_event_rule_kernel_kprobe_create(
602a6d40	285	const struct lttng_kernel_probe_location *location)
077192fd JR	286	{
077192fd JR	287	struct lttng_event_rule *rule = NULL;
85522de5	288	struct lttng_event_rule_kernel_kprobe *krule;
077192fd	289
85522de5	290	krule = zmalloc(sizeof(struct lttng_event_rule_kernel_kprobe));
077192fd JR	291	if (!krule) {
	292	goto end;
	293	}
	294
	295	rule = &krule->parent;
85522de5 JR	296	lttng_event_rule_init(&krule->parent, LTTNG_EVENT_RULE_TYPE_KERNEL_KPROBE);
	297	krule->parent.validate = lttng_event_rule_kernel_kprobe_validate;
	298	krule->parent.serialize = lttng_event_rule_kernel_kprobe_serialize;
	299	krule->parent.equal = lttng_event_rule_kernel_kprobe_is_equal;
	300	krule->parent.destroy = lttng_event_rule_kernel_kprobe_destroy;
077192fd	301	krule->parent.generate_filter_bytecode =
85522de5 JR	302	lttng_event_rule_kernel_kprobe_generate_filter_bytecode;
85522de5 JR	303	krule->parent.get_filter = lttng_event_rule_kernel_kprobe_get_filter;
077192fd	304	krule->parent.get_filter_bytecode =
85522de5	305	lttng_event_rule_kernel_kprobe_get_filter_bytecode;
077192fd	306	krule->parent.generate_exclusions =
85522de5 JR	307	lttng_event_rule_kernel_kprobe_generate_exclusions;
85522de5 JR	308	krule->parent.hash = lttng_event_rule_kernel_kprobe_hash;
6a751b95	309	krule->parent.mi_serialize = lttng_event_rule_kernel_kprobe_mi_serialize;
602a6d40 JR	310
	311	if (kernel_probe_set_location(krule, location)) {
	312	lttng_event_rule_destroy(rule);
	313	rule = NULL;
	314	}
	315
077192fd JR	316	end:
	317	return rule;
	318	}
	319
85522de5	320	ssize_t lttng_event_rule_kernel_kprobe_create_from_payload(
077192fd JR	321	struct lttng_payload_view *view,
	322	struct lttng_event_rule **_event_rule)
	323	{
	324	ssize_t ret, offset = 0;
	325	enum lttng_event_rule_status status;
85522de5	326	const struct lttng_event_rule_kernel_kprobe_comm *kprobe_comm;
077192fd JR	327	const char *name;
	328	struct lttng_buffer_view current_buffer_view;
	329	struct lttng_event_rule *rule = NULL;
602a6d40	330	struct lttng_kernel_probe_location *location = NULL;
077192fd JR	331
	332	if (!_event_rule) {
	333	ret = -1;
	334	goto end;
	335	}
	336
3e6e0df2 JG	337	current_buffer_view = lttng_buffer_view_from_view(
	338	&view->buffer, offset, sizeof(*kprobe_comm));
	339	if (!lttng_buffer_view_is_valid(&current_buffer_view)) {
077192fd JR	340	ERR("Failed to initialize from malformed event rule kprobe: buffer too short to contain header.");
	341	ret = -1;
	342	goto end;
	343	}
	344
077192fd	345	kprobe_comm = (typeof(kprobe_comm)) current_buffer_view.data;
077192fd	346
077192fd JR	347	/* Skip to payload */
	348	offset += current_buffer_view.size;
	349
	350	{
	351	/* Map the name. */
	352	struct lttng_payload_view current_payload_view =
	353	lttng_payload_view_from_view(view, offset,
	354	kprobe_comm->name_len);
	355
3e6e0df2	356	if (!lttng_payload_view_is_valid(&current_payload_view)) {
077192fd JR	357	ret = -1;
	358	goto end;
	359	}
	360
3e6e0df2	361	name = current_payload_view.buffer.data;
077192fd JR	362	if (!lttng_buffer_view_contains_string(
	363	&current_payload_view.buffer, name,
	364	kprobe_comm->name_len)) {
	365	ret = -1;
	366	goto end;
	367	}
	368	}
	369
	370	/* Skip after the name. */
	371	offset += kprobe_comm->name_len;
	372
	373	/* Map the kernel probe location. */
	374	{
	375	struct lttng_payload_view current_payload_view =
	376	lttng_payload_view_from_view(view, offset,
	377	kprobe_comm->location_len);
	378
3e6e0df2 JG	379	if (!lttng_payload_view_is_valid(&current_payload_view)) {
	380	ret = -1;
	381	goto end;
	382	}
	383
077192fd JR	384	ret = lttng_kernel_probe_location_create_from_payload(
	385	&current_payload_view, &location);
	386	if (ret < 0) {
	387	ret = -1;
	388	goto end;
	389	}
	390	}
	391
	392	if (ret != kprobe_comm->location_len) {
	393	ret = -1;
	394	goto end;
	395	}
	396
077192fd JR	397	/* Skip after the location */
	398	offset += kprobe_comm->location_len;
	399
85522de5	400	rule = lttng_event_rule_kernel_kprobe_create(location);
602a6d40 JR	401	if (!rule) {
	402	ERR("Failed to create event rule kprobe.");
	403	ret = -1;
	404	goto end;
	405	}
	406
85522de5	407	status = lttng_event_rule_kernel_kprobe_set_event_name(rule, name);
077192fd JR	408	if (status != LTTNG_EVENT_RULE_STATUS_OK) {
	409	ERR("Failed to set event rule kprobe name.");
	410	ret = -1;
	411	goto end;
	412	}
	413
	414	*_event_rule = rule;
	415	rule = NULL;
	416	ret = offset;
	417	end:
602a6d40	418	lttng_kernel_probe_location_destroy(location);
077192fd JR	419	lttng_event_rule_destroy(rule);
	420	return ret;
	421	}
	422
85522de5	423	enum lttng_event_rule_status lttng_event_rule_kernel_kprobe_get_location(
077192fd JR	424	const struct lttng_event_rule *rule,
	425	const struct lttng_kernel_probe_location **location)
	426	{
	427	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
85522de5	428	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd JR	429
	430	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !location) {
	431	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	432	goto end;
	433	}
	434
85522de5	435	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
077192fd JR	436	*location = kprobe->location;
	437
	438	if (!*location) {
	439	status = LTTNG_EVENT_RULE_STATUS_UNSET;
	440	goto end;
	441	}
	442
	443	end:
	444	return status;
	445	}
	446
85522de5	447	enum lttng_event_rule_status lttng_event_rule_kernel_kprobe_set_event_name(
077192fd JR	448	struct lttng_event_rule rule, const char name)
	449	{
	450	char *name_copy = NULL;
85522de5	451	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd JR	452	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
	453
	454	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !name \|\|
	455	strlen(name) == 0) {
	456	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	457	goto end;
	458	}
	459
85522de5	460	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
077192fd JR	461	name_copy = strdup(name);
	462	if (!name_copy) {
	463	status = LTTNG_EVENT_RULE_STATUS_ERROR;
	464	goto end;
	465	}
	466
	467	free(kprobe->name);
	468
	469	kprobe->name = name_copy;
	470	name_copy = NULL;
	471	end:
	472	return status;
	473	}
	474
85522de5	475	enum lttng_event_rule_status lttng_event_rule_kernel_kprobe_get_event_name(
077192fd JR	476	const struct lttng_event_rule rule, const char *name)
077192fd JR	477	{
85522de5	478	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd JR	479	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
	480
	481	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !name) {
	482	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	483	goto end;
	484	}
	485
85522de5	486	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
077192fd JR	487	if (!kprobe->name) {
	488	status = LTTNG_EVENT_RULE_STATUS_UNSET;
	489	goto end;
	490	}
	491
	492	*name = kprobe->name;
	493	end:
	494	return status;
	495	}