[lttng-tools.git] / src / common / event-rule / kernel-kprobe.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 <ctype.h>
#include <lttng/constant.h>
#include <lttng/event-rule/event-rule-internal.hpp>
#include <lttng/event-rule/event-rule.h>
#include <lttng/event-rule/kernel-kprobe-internal.hpp>
#include <lttng/kernel-probe-internal.hpp>
#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 __attribute__((unused)),
		const struct lttng_credentials *creds __attribute__((unused)))
{
	/* Nothing to do. */
	return LTTNG_OK;
}

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

static const struct lttng_bytecode *
lttng_event_rule_kernel_kprobe_get_filter_bytecode(
		const struct lttng_event_rule *rule __attribute__((unused)))
{
	/* 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 __attribute__((unused)),
		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<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
c9e313bc SM	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>
077192fd JR	17	#include <ctype.h>
077192fd JR	18	#include <lttng/constant.h>
c9e313bc	19	#include <lttng/event-rule/event-rule-internal.hpp>
6a751b95	20	#include <lttng/event-rule/event-rule.h>
c9e313bc SM	21	#include <lttng/event-rule/kernel-kprobe-internal.hpp>
c9e313bc SM	22	#include <lttng/kernel-probe-internal.hpp>
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(
f46376a1 MJ	153	struct lttng_event_rule *rule __attribute__((unused)),
f46376a1 MJ	154	const struct lttng_credentials *creds __attribute__((unused)))
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(
f46376a1	161	const struct lttng_event_rule *rule __attribute__((unused)))
077192fd JR	162	{
	163	/* Not supported. */
	164	return NULL;
	165	}
	166
2b00d462	167	static const struct lttng_bytecode *
f46376a1 MJ	168	lttng_event_rule_kernel_kprobe_get_filter_bytecode(
f46376a1 MJ	169	const struct lttng_event_rule *rule __attribute__((unused)))
077192fd JR	170	{
	171	/* Not supported. */
	172	return NULL;
	173	}
	174
993578ff	175	static enum lttng_event_rule_generate_exclusions_status
f46376a1 MJ	176	lttng_event_rule_kernel_kprobe_generate_exclusions(
f46376a1 MJ	177	const struct lttng_event_rule *rule __attribute__((unused)),
993578ff	178	struct lttng_event_exclusion **exclusions)
077192fd JR	179	{
077192fd JR	180	/* Not supported. */
993578ff JR	181	*exclusions = NULL;
993578ff JR	182	return LTTNG_EVENT_RULE_GENERATE_EXCLUSIONS_STATUS_NONE;
077192fd JR	183	}
077192fd JR	184
959e3c66	185	static unsigned long
85522de5	186	lttng_event_rule_kernel_kprobe_hash(
959e3c66 JR	187	const struct lttng_event_rule *rule)
	188	{
	189	unsigned long hash;
85522de5	190	struct lttng_event_rule_kernel_kprobe *krule =
959e3c66 JR	191	container_of(rule, typeof(*krule), parent);
959e3c66 JR	192
85522de5	193	hash = hash_key_ulong((void *) LTTNG_EVENT_RULE_TYPE_KERNEL_KPROBE,
959e3c66 JR	194	lttng_ht_seed);
	195	hash ^= hash_key_str(krule->name, lttng_ht_seed);
	196	hash ^= lttng_kernel_probe_location_hash(krule->location);
	197
	198	return hash;
	199	}
	200
602a6d40 JR	201	static
602a6d40 JR	202	int kernel_probe_set_location(
85522de5	203	struct lttng_event_rule_kernel_kprobe *kprobe,
602a6d40 JR	204	const struct lttng_kernel_probe_location *location)
	205	{
	206	int ret;
	207	struct lttng_kernel_probe_location *location_copy = NULL;
	208
	209	if (!kprobe \|\| !location \|\| kprobe->location) {
	210	ret = -1;
	211	goto end;
	212	}
	213
	214	location_copy = lttng_kernel_probe_location_copy(location);
	215	if (!location_copy) {
	216	ret = -1;
	217	goto end;
	218	}
	219
	220	kprobe->location = location_copy;
	221	location_copy = NULL;
	222	ret = 0;
	223	end:
	224	lttng_kernel_probe_location_destroy(location_copy);
	225	return ret;
	226	}
	227
6a751b95 JR	228	static
	229	enum lttng_error_code lttng_event_rule_kernel_kprobe_mi_serialize(
	230	const struct lttng_event_rule rule, struct mi_writer writer)
	231	{
	232	int ret;
	233	enum lttng_error_code ret_code;
	234	enum lttng_event_rule_status status;
	235	const char *event_name = NULL;
	236	const struct lttng_kernel_probe_location *location = NULL;
	237
a0377dfe FD	238	LTTNG_ASSERT(rule);
	239	LTTNG_ASSERT(writer);
	240	LTTNG_ASSERT(IS_KPROBE_EVENT_RULE(rule));
6a751b95 JR	241
	242	status = lttng_event_rule_kernel_kprobe_get_event_name(
	243	rule, &event_name);
a0377dfe FD	244	LTTNG_ASSERT(status == LTTNG_EVENT_RULE_STATUS_OK);
a0377dfe FD	245	LTTNG_ASSERT(event_name);
6a751b95 JR	246
6a751b95 JR	247	status = lttng_event_rule_kernel_kprobe_get_location(rule, &location);
a0377dfe FD	248	LTTNG_ASSERT(status == LTTNG_EVENT_RULE_STATUS_OK);
a0377dfe FD	249	LTTNG_ASSERT(location);
6a751b95 JR	250
	251	/* Open event rule kernel kprobe element. */
	252	ret = mi_lttng_writer_open_element(
	253	writer, mi_lttng_element_event_rule_kernel_kprobe);
	254	if (ret) {
	255	goto mi_error;
	256	}
	257
	258	/* Name. */
	259	ret = mi_lttng_writer_write_element_string(writer,
	260	mi_lttng_element_event_rule_event_name, event_name);
	261	if (ret) {
	262	goto mi_error;
	263	}
	264
	265	/* Probe location. */
	266	ret_code = lttng_kernel_probe_location_mi_serialize(location, writer);
	267	if (ret_code != LTTNG_OK) {
	268	goto end;
	269	}
	270
	271	/* Close event rule kernel kprobe element. */
	272	ret = mi_lttng_writer_close_element(writer);
	273	if (ret) {
	274	goto mi_error;
	275	}
	276
	277	ret_code = LTTNG_OK;
	278	goto end;
	279
	280	mi_error:
	281	ret_code = LTTNG_ERR_MI_IO_FAIL;
	282	end:
	283	return ret_code;
	284	}
	285
85522de5	286	struct lttng_event_rule *lttng_event_rule_kernel_kprobe_create(
602a6d40	287	const struct lttng_kernel_probe_location *location)
077192fd JR	288	{
077192fd JR	289	struct lttng_event_rule *rule = NULL;
85522de5	290	struct lttng_event_rule_kernel_kprobe *krule;
077192fd	291
64803277	292	krule = zmalloc<lttng_event_rule_kernel_kprobe>();
077192fd JR	293	if (!krule) {
	294	goto end;
	295	}
	296
	297	rule = &krule->parent;
85522de5 JR	298	lttng_event_rule_init(&krule->parent, LTTNG_EVENT_RULE_TYPE_KERNEL_KPROBE);
	299	krule->parent.validate = lttng_event_rule_kernel_kprobe_validate;
	300	krule->parent.serialize = lttng_event_rule_kernel_kprobe_serialize;
	301	krule->parent.equal = lttng_event_rule_kernel_kprobe_is_equal;
	302	krule->parent.destroy = lttng_event_rule_kernel_kprobe_destroy;
077192fd	303	krule->parent.generate_filter_bytecode =
85522de5 JR	304	lttng_event_rule_kernel_kprobe_generate_filter_bytecode;
85522de5 JR	305	krule->parent.get_filter = lttng_event_rule_kernel_kprobe_get_filter;
077192fd	306	krule->parent.get_filter_bytecode =
85522de5	307	lttng_event_rule_kernel_kprobe_get_filter_bytecode;
077192fd	308	krule->parent.generate_exclusions =
85522de5 JR	309	lttng_event_rule_kernel_kprobe_generate_exclusions;
85522de5 JR	310	krule->parent.hash = lttng_event_rule_kernel_kprobe_hash;
6a751b95	311	krule->parent.mi_serialize = lttng_event_rule_kernel_kprobe_mi_serialize;
602a6d40 JR	312
	313	if (kernel_probe_set_location(krule, location)) {
	314	lttng_event_rule_destroy(rule);
	315	rule = NULL;
	316	}
	317
077192fd JR	318	end:
	319	return rule;
	320	}
	321
85522de5	322	ssize_t lttng_event_rule_kernel_kprobe_create_from_payload(
077192fd JR	323	struct lttng_payload_view *view,
	324	struct lttng_event_rule **_event_rule)
	325	{
	326	ssize_t ret, offset = 0;
	327	enum lttng_event_rule_status status;
85522de5	328	const struct lttng_event_rule_kernel_kprobe_comm *kprobe_comm;
077192fd JR	329	const char *name;
	330	struct lttng_buffer_view current_buffer_view;
	331	struct lttng_event_rule *rule = NULL;
602a6d40	332	struct lttng_kernel_probe_location *location = NULL;
077192fd JR	333
	334	if (!_event_rule) {
	335	ret = -1;
	336	goto end;
	337	}
	338
3e6e0df2 JG	339	current_buffer_view = lttng_buffer_view_from_view(
	340	&view->buffer, offset, sizeof(*kprobe_comm));
	341	if (!lttng_buffer_view_is_valid(&current_buffer_view)) {
077192fd JR	342	ERR("Failed to initialize from malformed event rule kprobe: buffer too short to contain header.");
	343	ret = -1;
	344	goto end;
	345	}
	346
077192fd	347	kprobe_comm = (typeof(kprobe_comm)) current_buffer_view.data;
077192fd	348
077192fd JR	349	/* Skip to payload */
	350	offset += current_buffer_view.size;
	351
	352	{
	353	/* Map the name. */
	354	struct lttng_payload_view current_payload_view =
	355	lttng_payload_view_from_view(view, offset,
	356	kprobe_comm->name_len);
	357
3e6e0df2	358	if (!lttng_payload_view_is_valid(&current_payload_view)) {
077192fd JR	359	ret = -1;
	360	goto end;
	361	}
	362
3e6e0df2	363	name = current_payload_view.buffer.data;
077192fd JR	364	if (!lttng_buffer_view_contains_string(
	365	&current_payload_view.buffer, name,
	366	kprobe_comm->name_len)) {
	367	ret = -1;
	368	goto end;
	369	}
	370	}
	371
	372	/* Skip after the name. */
	373	offset += kprobe_comm->name_len;
	374
	375	/* Map the kernel probe location. */
	376	{
	377	struct lttng_payload_view current_payload_view =
	378	lttng_payload_view_from_view(view, offset,
	379	kprobe_comm->location_len);
	380
3e6e0df2 JG	381	if (!lttng_payload_view_is_valid(&current_payload_view)) {
	382	ret = -1;
	383	goto end;
	384	}
	385
077192fd JR	386	ret = lttng_kernel_probe_location_create_from_payload(
	387	&current_payload_view, &location);
	388	if (ret < 0) {
	389	ret = -1;
	390	goto end;
	391	}
	392	}
	393
	394	if (ret != kprobe_comm->location_len) {
	395	ret = -1;
	396	goto end;
	397	}
	398
077192fd JR	399	/* Skip after the location */
	400	offset += kprobe_comm->location_len;
	401
85522de5	402	rule = lttng_event_rule_kernel_kprobe_create(location);
602a6d40 JR	403	if (!rule) {
	404	ERR("Failed to create event rule kprobe.");
	405	ret = -1;
	406	goto end;
	407	}
	408
85522de5	409	status = lttng_event_rule_kernel_kprobe_set_event_name(rule, name);
077192fd JR	410	if (status != LTTNG_EVENT_RULE_STATUS_OK) {
	411	ERR("Failed to set event rule kprobe name.");
	412	ret = -1;
	413	goto end;
	414	}
	415
	416	*_event_rule = rule;
	417	rule = NULL;
	418	ret = offset;
	419	end:
602a6d40	420	lttng_kernel_probe_location_destroy(location);
077192fd JR	421	lttng_event_rule_destroy(rule);
	422	return ret;
	423	}
	424
85522de5	425	enum lttng_event_rule_status lttng_event_rule_kernel_kprobe_get_location(
077192fd JR	426	const struct lttng_event_rule *rule,
	427	const struct lttng_kernel_probe_location **location)
	428	{
	429	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
85522de5	430	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd JR	431
	432	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !location) {
	433	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	434	goto end;
	435	}
	436
85522de5	437	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
077192fd JR	438	*location = kprobe->location;
	439
	440	if (!*location) {
	441	status = LTTNG_EVENT_RULE_STATUS_UNSET;
	442	goto end;
	443	}
	444
	445	end:
	446	return status;
	447	}
	448
85522de5	449	enum lttng_event_rule_status lttng_event_rule_kernel_kprobe_set_event_name(
077192fd JR	450	struct lttng_event_rule rule, const char name)
	451	{
	452	char *name_copy = NULL;
85522de5	453	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd JR	454	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
	455
	456	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !name \|\|
	457	strlen(name) == 0) {
	458	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	459	goto end;
	460	}
	461
85522de5	462	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
077192fd JR	463	name_copy = strdup(name);
	464	if (!name_copy) {
	465	status = LTTNG_EVENT_RULE_STATUS_ERROR;
	466	goto end;
	467	}
	468
	469	free(kprobe->name);
	470
	471	kprobe->name = name_copy;
	472	name_copy = NULL;
	473	end:
	474	return status;
	475	}
	476
85522de5	477	enum lttng_event_rule_status lttng_event_rule_kernel_kprobe_get_event_name(
077192fd JR	478	const struct lttng_event_rule rule, const char *name)
077192fd JR	479	{
85522de5	480	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd JR	481	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
	482
	483	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !name) {
	484	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	485	goto end;
	486	}
	487
85522de5	488	kprobe = container_of(rule, struct lttng_event_rule_kernel_kprobe, parent);
077192fd JR	489	if (!kprobe->name) {
	490	status = LTTNG_EVENT_RULE_STATUS_UNSET;
	491	goto end;
	492	}
	493
	494	*name = kprobe->name;
	495	end:
	496	return status;
	497	}