[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 <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 <ctype.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 = lttng::utils::container_of(rule, &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 = lttng::utils::container_of(rule, &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 = lttng::utils::container_of(rule, &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 = lttng::utils::container_of(_a, &lttng_event_rule_kernel_kprobe::parent);
	b = lttng::utils::container_of(_b, &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 nullptr;
}

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

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 = nullptr;
	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 =
		lttng::utils::container_of(rule, &lttng_event_rule_kernel_kprobe::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 = nullptr;

	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 = nullptr;
	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 = nullptr;
	const struct lttng_kernel_probe_location *location = nullptr;

	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 = nullptr;
	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 = nullptr;
	}

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 = nullptr;
	struct lttng_kernel_probe_location *location = nullptr;

	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 = nullptr;
	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 = lttng::utils::container_of(rule, &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 = nullptr;
	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 = lttng::utils::container_of(rule, &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 = nullptr;
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 = lttng::utils::container_of(rule, &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>
28ab034a	17
077192fd	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>
28ab034a JG	24
28ab034a JG	25	#include <ctype.h>
077192fd JR	26	#include <stdio.h>
	27
	28	#define IS_KPROBE_EVENT_RULE(rule) \
85522de5	29	(lttng_event_rule_get_type(rule) == LTTNG_EVENT_RULE_TYPE_KERNEL_KPROBE)
077192fd JR	30
	31	#if (LTTNG_SYMBOL_NAME_LEN == 256)
	32	#define LTTNG_SYMBOL_NAME_LEN_SCANF_IS_A_BROKEN_API "255"
	33	#endif
	34
85522de5	35	static void lttng_event_rule_kernel_kprobe_destroy(struct lttng_event_rule *rule)
077192fd	36	{
85522de5	37	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd	38
0114db0e	39	kprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_kprobe::parent);
077192fd JR	40
	41	lttng_kernel_probe_location_destroy(kprobe->location);
	42	free(kprobe->name);
	43	free(kprobe);
	44	}
	45
28ab034a	46	static bool lttng_event_rule_kernel_kprobe_validate(const struct lttng_event_rule *rule)
077192fd JR	47	{
077192fd JR	48	bool valid = false;
85522de5	49	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd JR	50
	51	if (!rule) {
	52	goto end;
	53	}
	54
0114db0e	55	kprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_kprobe::parent);
077192fd JR	56
	57	/* Required field. */
	58	if (!kprobe->name) {
	59	ERR("Invalid name event rule: a name must be set.");
	60	goto end;
	61	}
	62
	63	/* Required field. */
28ab034a	64	if (!kprobe->location) {
077192fd JR	65	ERR("Invalid name event rule: a location must be set.");
	66	goto end;
	67	}
	68
	69	valid = true;
	70	end:
	71	return valid;
	72	}
	73
28ab034a JG	74	static int lttng_event_rule_kernel_kprobe_serialize(const struct lttng_event_rule *rule,
28ab034a JG	75	struct lttng_payload *payload)
077192fd JR	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.");
0114db0e	91	kprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_kprobe::parent);
077192fd JR	92
	93	name_len = strlen(kprobe->name) + 1;
	94	kprobe_comm.name_len = name_len;
	95
28ab034a	96	ret = lttng_dynamic_buffer_append(&payload->buffer, &kprobe_comm, sizeof(kprobe_comm));
077192fd JR	97	if (ret) {
	98	goto end;
	99	}
	100
	101	ret = lttng_dynamic_buffer_append(&payload->buffer, kprobe->name, name_len);
	102	if (ret) {
	103	goto end;
	104	}
	105
	106	size_before_location = payload->buffer.size;
	107
	108	ret = lttng_kernel_probe_location_serialize(kprobe->location, payload);
	109	if (ret < 0) {
	110	goto end;
	111	}
	112
	113	/* Update the header regarding the probe size. */
28ab034a JG	114	header = (struct lttng_event_rule_kernel_kprobe_comm ) ((char ) payload->buffer.data +
28ab034a JG	115	header_offset);
077192fd JR	116	header->location_len = payload->buffer.size - size_before_location;
	117
	118	ret = 0;
	119
	120	end:
	121	return ret;
	122	}
	123
85522de5	124	static bool lttng_event_rule_kernel_kprobe_is_equal(const struct lttng_event_rule *_a,
28ab034a	125	const struct lttng_event_rule *_b)
077192fd JR	126	{
077192fd JR	127	bool is_equal = false;
85522de5	128	struct lttng_event_rule_kernel_kprobe a, b;
077192fd	129
0114db0e JG	130	a = lttng::utils::container_of(_a, &lttng_event_rule_kernel_kprobe::parent);
0114db0e JG	131	b = lttng::utils::container_of(_b, &lttng_event_rule_kernel_kprobe::parent);
077192fd JR	132
	133	/* Quick checks */
	134	if (!!a->name != !!b->name) {
	135	goto end;
	136	}
	137
	138	/* Long check */
a0377dfe FD	139	LTTNG_ASSERT(a->name);
a0377dfe FD	140	LTTNG_ASSERT(b->name);
077192fd JR	141	if (strcmp(a->name, b->name)) {
	142	goto end;
	143	}
	144
28ab034a	145	is_equal = lttng_kernel_probe_location_is_equal(a->location, b->location);
077192fd JR	146	end:
	147	return is_equal;
	148	}
	149
85522de5	150	static enum lttng_error_code lttng_event_rule_kernel_kprobe_generate_filter_bytecode(
28ab034a JG	151	struct lttng_event_rule *rule __attribute__((unused)),
28ab034a JG	152	const struct lttng_credentials *creds __attribute__((unused)))
077192fd JR	153	{
	154	/* Nothing to do. */
	155	return LTTNG_OK;
	156	}
	157
28ab034a JG	158	static const char lttng_event_rule_kernel_kprobe_get_filter(const struct lttng_event_rule rule
28ab034a JG	159	__attribute__((unused)))
077192fd JR	160	{
077192fd JR	161	/* Not supported. */
cd9adb8b	162	return nullptr;
077192fd JR	163	}
077192fd JR	164
2b00d462	165	static const struct lttng_bytecode *
28ab034a JG	166	lttng_event_rule_kernel_kprobe_get_filter_bytecode(const struct lttng_event_rule *rule
28ab034a JG	167	__attribute__((unused)))
077192fd JR	168	{
077192fd JR	169	/* Not supported. */
cd9adb8b	170	return nullptr;
077192fd JR	171	}
077192fd JR	172
993578ff	173	static enum lttng_event_rule_generate_exclusions_status
28ab034a JG	174	lttng_event_rule_kernel_kprobe_generate_exclusions(const struct lttng_event_rule *rule
	175	__attribute__((unused)),
	176	struct lttng_event_exclusion **exclusions)
077192fd JR	177	{
077192fd JR	178	/* Not supported. */
cd9adb8b	179	*exclusions = nullptr;
993578ff	180	return LTTNG_EVENT_RULE_GENERATE_EXCLUSIONS_STATUS_NONE;
077192fd JR	181	}
077192fd JR	182
28ab034a	183	static unsigned long lttng_event_rule_kernel_kprobe_hash(const struct lttng_event_rule *rule)
959e3c66 JR	184	{
959e3c66 JR	185	unsigned long hash;
85522de5	186	struct lttng_event_rule_kernel_kprobe *krule =
28ab034a	187	lttng::utils::container_of(rule, &lttng_event_rule_kernel_kprobe::parent);
959e3c66	188
28ab034a	189	hash = hash_key_ulong((void *) LTTNG_EVENT_RULE_TYPE_KERNEL_KPROBE, lttng_ht_seed);
959e3c66 JR	190	hash ^= hash_key_str(krule->name, lttng_ht_seed);
	191	hash ^= lttng_kernel_probe_location_hash(krule->location);
	192
	193	return hash;
	194	}
	195
28ab034a JG	196	static int kernel_probe_set_location(struct lttng_event_rule_kernel_kprobe *kprobe,
28ab034a JG	197	const struct lttng_kernel_probe_location *location)
602a6d40 JR	198	{
602a6d40 JR	199	int ret;
cd9adb8b	200	struct lttng_kernel_probe_location *location_copy = nullptr;
602a6d40 JR	201
	202	if (!kprobe \|\| !location \|\| kprobe->location) {
	203	ret = -1;
	204	goto end;
	205	}
	206
	207	location_copy = lttng_kernel_probe_location_copy(location);
	208	if (!location_copy) {
	209	ret = -1;
	210	goto end;
	211	}
	212
	213	kprobe->location = location_copy;
cd9adb8b	214	location_copy = nullptr;
602a6d40 JR	215	ret = 0;
	216	end:
	217	lttng_kernel_probe_location_destroy(location_copy);
	218	return ret;
	219	}
	220
28ab034a JG	221	static enum lttng_error_code
	222	lttng_event_rule_kernel_kprobe_mi_serialize(const struct lttng_event_rule *rule,
	223	struct mi_writer *writer)
6a751b95 JR	224	{
	225	int ret;
	226	enum lttng_error_code ret_code;
	227	enum lttng_event_rule_status status;
cd9adb8b JG	228	const char *event_name = nullptr;
cd9adb8b JG	229	const struct lttng_kernel_probe_location *location = nullptr;
6a751b95	230
a0377dfe FD	231	LTTNG_ASSERT(rule);
	232	LTTNG_ASSERT(writer);
	233	LTTNG_ASSERT(IS_KPROBE_EVENT_RULE(rule));
6a751b95	234
28ab034a	235	status = lttng_event_rule_kernel_kprobe_get_event_name(rule, &event_name);
a0377dfe FD	236	LTTNG_ASSERT(status == LTTNG_EVENT_RULE_STATUS_OK);
a0377dfe FD	237	LTTNG_ASSERT(event_name);
6a751b95 JR	238
6a751b95 JR	239	status = lttng_event_rule_kernel_kprobe_get_location(rule, &location);
a0377dfe FD	240	LTTNG_ASSERT(status == LTTNG_EVENT_RULE_STATUS_OK);
a0377dfe FD	241	LTTNG_ASSERT(location);
6a751b95 JR	242
6a751b95 JR	243	/* Open event rule kernel kprobe element. */
28ab034a	244	ret = mi_lttng_writer_open_element(writer, mi_lttng_element_event_rule_kernel_kprobe);
6a751b95 JR	245	if (ret) {
	246	goto mi_error;
	247	}
	248
	249	/* Name. */
28ab034a JG	250	ret = mi_lttng_writer_write_element_string(
28ab034a JG	251	writer, mi_lttng_element_event_rule_event_name, event_name);
6a751b95 JR	252	if (ret) {
	253	goto mi_error;
	254	}
	255
	256	/* Probe location. */
	257	ret_code = lttng_kernel_probe_location_mi_serialize(location, writer);
	258	if (ret_code != LTTNG_OK) {
	259	goto end;
	260	}
	261
	262	/* Close event rule kernel kprobe element. */
	263	ret = mi_lttng_writer_close_element(writer);
	264	if (ret) {
	265	goto mi_error;
	266	}
	267
	268	ret_code = LTTNG_OK;
	269	goto end;
	270
	271	mi_error:
	272	ret_code = LTTNG_ERR_MI_IO_FAIL;
	273	end:
	274	return ret_code;
	275	}
	276
28ab034a JG	277	struct lttng_event_rule *
28ab034a JG	278	lttng_event_rule_kernel_kprobe_create(const struct lttng_kernel_probe_location *location)
077192fd	279	{
cd9adb8b	280	struct lttng_event_rule *rule = nullptr;
85522de5	281	struct lttng_event_rule_kernel_kprobe *krule;
077192fd	282
64803277	283	krule = zmalloc<lttng_event_rule_kernel_kprobe>();
077192fd JR	284	if (!krule) {
	285	goto end;
	286	}
	287
	288	rule = &krule->parent;
85522de5 JR	289	lttng_event_rule_init(&krule->parent, LTTNG_EVENT_RULE_TYPE_KERNEL_KPROBE);
	290	krule->parent.validate = lttng_event_rule_kernel_kprobe_validate;
	291	krule->parent.serialize = lttng_event_rule_kernel_kprobe_serialize;
	292	krule->parent.equal = lttng_event_rule_kernel_kprobe_is_equal;
	293	krule->parent.destroy = lttng_event_rule_kernel_kprobe_destroy;
077192fd	294	krule->parent.generate_filter_bytecode =
28ab034a	295	lttng_event_rule_kernel_kprobe_generate_filter_bytecode;
85522de5	296	krule->parent.get_filter = lttng_event_rule_kernel_kprobe_get_filter;
28ab034a JG	297	krule->parent.get_filter_bytecode = lttng_event_rule_kernel_kprobe_get_filter_bytecode;
28ab034a JG	298	krule->parent.generate_exclusions = lttng_event_rule_kernel_kprobe_generate_exclusions;
85522de5	299	krule->parent.hash = lttng_event_rule_kernel_kprobe_hash;
6a751b95	300	krule->parent.mi_serialize = lttng_event_rule_kernel_kprobe_mi_serialize;
602a6d40 JR	301
	302	if (kernel_probe_set_location(krule, location)) {
	303	lttng_event_rule_destroy(rule);
cd9adb8b	304	rule = nullptr;
602a6d40 JR	305	}
602a6d40 JR	306
077192fd JR	307	end:
	308	return rule;
	309	}
	310
28ab034a JG	311	ssize_t lttng_event_rule_kernel_kprobe_create_from_payload(struct lttng_payload_view *view,
28ab034a JG	312	struct lttng_event_rule **_event_rule)
077192fd JR	313	{
	314	ssize_t ret, offset = 0;
	315	enum lttng_event_rule_status status;
85522de5	316	const struct lttng_event_rule_kernel_kprobe_comm *kprobe_comm;
077192fd JR	317	const char *name;
077192fd JR	318	struct lttng_buffer_view current_buffer_view;
cd9adb8b JG	319	struct lttng_event_rule *rule = nullptr;
cd9adb8b JG	320	struct lttng_kernel_probe_location *location = nullptr;
077192fd JR	321
	322	if (!_event_rule) {
	323	ret = -1;
	324	goto end;
	325	}
	326
28ab034a JG	327	current_buffer_view =
28ab034a JG	328	lttng_buffer_view_from_view(&view->buffer, offset, sizeof(*kprobe_comm));
3e6e0df2	329	if (!lttng_buffer_view_is_valid(&current_buffer_view)) {
077192fd JR	330	ERR("Failed to initialize from malformed event rule kprobe: buffer too short to contain header.");
	331	ret = -1;
	332	goto end;
	333	}
	334
077192fd	335	kprobe_comm = (typeof(kprobe_comm)) current_buffer_view.data;
077192fd	336
077192fd JR	337	/* Skip to payload */
	338	offset += current_buffer_view.size;
	339
	340	{
	341	/* Map the name. */
	342	struct lttng_payload_view current_payload_view =
28ab034a	343	lttng_payload_view_from_view(view, offset, kprobe_comm->name_len);
077192fd	344
3e6e0df2	345	if (!lttng_payload_view_is_valid(&current_payload_view)) {
077192fd JR	346	ret = -1;
	347	goto end;
	348	}
	349
3e6e0df2	350	name = current_payload_view.buffer.data;
077192fd	351	if (!lttng_buffer_view_contains_string(
28ab034a	352	&current_payload_view.buffer, name, kprobe_comm->name_len)) {
077192fd JR	353	ret = -1;
	354	goto end;
	355	}
	356	}
	357
	358	/* Skip after the name. */
	359	offset += kprobe_comm->name_len;
	360
	361	/* Map the kernel probe location. */
	362	{
	363	struct lttng_payload_view current_payload_view =
28ab034a	364	lttng_payload_view_from_view(view, offset, kprobe_comm->location_len);
077192fd	365
3e6e0df2 JG	366	if (!lttng_payload_view_is_valid(&current_payload_view)) {
	367	ret = -1;
	368	goto end;
	369	}
	370
28ab034a JG	371	ret = lttng_kernel_probe_location_create_from_payload(&current_payload_view,
28ab034a JG	372	&location);
077192fd JR	373	if (ret < 0) {
	374	ret = -1;
	375	goto end;
	376	}
	377	}
	378
	379	if (ret != kprobe_comm->location_len) {
	380	ret = -1;
	381	goto end;
	382	}
	383
077192fd JR	384	/* Skip after the location */
	385	offset += kprobe_comm->location_len;
	386
85522de5	387	rule = lttng_event_rule_kernel_kprobe_create(location);
602a6d40 JR	388	if (!rule) {
	389	ERR("Failed to create event rule kprobe.");
	390	ret = -1;
	391	goto end;
	392	}
	393
85522de5	394	status = lttng_event_rule_kernel_kprobe_set_event_name(rule, name);
077192fd JR	395	if (status != LTTNG_EVENT_RULE_STATUS_OK) {
	396	ERR("Failed to set event rule kprobe name.");
	397	ret = -1;
	398	goto end;
	399	}
	400
	401	*_event_rule = rule;
cd9adb8b	402	rule = nullptr;
077192fd JR	403	ret = offset;
077192fd JR	404	end:
602a6d40	405	lttng_kernel_probe_location_destroy(location);
077192fd JR	406	lttng_event_rule_destroy(rule);
	407	return ret;
	408	}
	409
28ab034a JG	410	enum lttng_event_rule_status
	411	lttng_event_rule_kernel_kprobe_get_location(const struct lttng_event_rule *rule,
	412	const struct lttng_kernel_probe_location **location)
077192fd JR	413	{
077192fd JR	414	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
85522de5	415	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd JR	416
	417	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !location) {
	418	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	419	goto end;
	420	}
	421
0114db0e	422	kprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_kprobe::parent);
077192fd JR	423	*location = kprobe->location;
	424
	425	if (!*location) {
	426	status = LTTNG_EVENT_RULE_STATUS_UNSET;
	427	goto end;
	428	}
	429
	430	end:
	431	return status;
	432	}
	433
28ab034a JG	434	enum lttng_event_rule_status
28ab034a JG	435	lttng_event_rule_kernel_kprobe_set_event_name(struct lttng_event_rule rule, const char name)
077192fd	436	{
cd9adb8b	437	char *name_copy = nullptr;
85522de5	438	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd JR	439	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
077192fd JR	440
28ab034a	441	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !name \|\| strlen(name) == 0) {
077192fd JR	442	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	443	goto end;
	444	}
	445
0114db0e	446	kprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_kprobe::parent);
077192fd JR	447	name_copy = strdup(name);
	448	if (!name_copy) {
	449	status = LTTNG_EVENT_RULE_STATUS_ERROR;
	450	goto end;
	451	}
	452
	453	free(kprobe->name);
	454
	455	kprobe->name = name_copy;
cd9adb8b	456	name_copy = nullptr;
077192fd JR	457	end:
	458	return status;
	459	}
	460
28ab034a JG	461	enum lttng_event_rule_status
	462	lttng_event_rule_kernel_kprobe_get_event_name(const struct lttng_event_rule *rule,
	463	const char **name)
077192fd	464	{
85522de5	465	struct lttng_event_rule_kernel_kprobe *kprobe;
077192fd JR	466	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
	467
	468	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !name) {
	469	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	470	goto end;
	471	}
	472
0114db0e	473	kprobe = lttng::utils::container_of(rule, &lttng_event_rule_kernel_kprobe::parent);
077192fd JR	474	if (!kprobe->name) {
	475	status = LTTNG_EVENT_RULE_STATUS_UNSET;
	476	goto end;
	477	}
	478
	479	*name = kprobe->name;
	480	end:
	481	return status;
	482	}