X-Git-Url: https://git.efficios.com/?a=blobdiff_plain;f=src%2Fcommon%2Fevent-rule%2Fkernel-function.c;fp=src%2Fcommon%2Fevent-rule%2Fkernel-function.c;h=c5dd61938ec68e6417cb752483c9c315e9b8fdb1;hb=c3e68e71e0bca1c067bf24447163ac6850a9b09e;hp=0000000000000000000000000000000000000000;hpb=11f6ce94d8fb73f017888681aaba5d7df55fc735;p=deliverable%2Flttng-tools.git

diff --git a/src/common/event-rule/kernel-function.c b/src/common/event-rule/kernel-function.c
new file mode 100644
index 000000000..c5dd61938
--- /dev/null
+++ b/src/common/event-rule/kernel-function.c
@@ -0,0 +1,437 @@
+/*
+ * Copyright (C) 2021 Francis Deslauriers <francis.deslauriers@efficios.com>
+ *
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ */
+
+#include <assert.h>
+#include <common/credentials.h>
+#include <common/error.h>
+#include <common/macros.h>
+#include <common/payload.h>
+#include <common/payload-view.h>
+#include <common/runas.h>
+#include <common/hashtable/hashtable.h>
+#include <common/hashtable/utils.h>
+#include <ctype.h>
+#include <lttng/constant.h>
+#include <lttng/event-rule/event-rule.h>
+#include <lttng/event-rule/event-rule-internal.h>
+#include <lttng/event-rule/kernel-function-internal.h>
+#include <lttng/kernel-function.h>
+#include <lttng/kernel-function-internal.h>
+#include <stdio.h>
+
+#define IS_KERNEL_FUNCTION_EVENT_RULE(rule) \
+	(lttng_event_rule_get_type(rule) == LTTNG_EVENT_RULE_TYPE_KERNEL_FUNCTION)
+
+#if (LTTNG_SYMBOL_NAME_LEN == 256)
+#define LTTNG_SYMBOL_NAME_LEN_SCANF_IS_A_BROKEN_API "255"
+#endif
+
+static void lttng_event_rule_kernel_function_destroy(struct lttng_event_rule *rule)
+{
+	struct lttng_event_rule_kernel_function *kfunction;
+
+	kfunction = container_of(rule, struct lttng_event_rule_kernel_function, parent);
+
+	lttng_kernel_function_location_destroy(kfunction->location);
+	free(kfunction->name);
+	free(kfunction);
+}
+
+static bool lttng_event_rule_kernel_function_validate(
+		const struct lttng_event_rule *rule)
+{
+	bool valid = false;
+	struct lttng_event_rule_kernel_function *kfunction;
+
+	if (!rule) {
+		goto end;
+	}
+
+	kfunction = container_of(rule, struct lttng_event_rule_kernel_function, parent);
+
+	/* Required field. */
+	if (!kfunction->name) {
+		ERR("Invalid name event rule: a name must be set.");
+		goto end;
+	}
+
+	/* Required field. */
+	if(!kfunction->location) {
+		ERR("Invalid name event rule: a location must be set.");
+		goto end;
+	}
+
+	valid = true;
+end:
+	return valid;
+}
+
+static int lttng_event_rule_kernel_function_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_function *kfunction;
+	struct lttng_event_rule_kernel_function_comm kfunction_comm;
+	struct lttng_event_rule_kernel_function_comm *header;
+
+	if (!rule || !IS_KERNEL_FUNCTION_EVENT_RULE(rule)) {
+		ret = -1;
+		goto end;
+	}
+
+	header_offset = payload->buffer.size;
+
+	DBG("Serializing kfunction event rule.");
+	kfunction = container_of(rule, struct lttng_event_rule_kernel_function, parent);
+
+	name_len = strlen(kfunction->name) + 1;
+	kfunction_comm.name_len = name_len;
+
+	ret = lttng_dynamic_buffer_append(
+			&payload->buffer, &kfunction_comm, sizeof(kfunction_comm));
+	if (ret) {
+		goto end;
+	}
+
+	ret = lttng_dynamic_buffer_append(&payload->buffer, kfunction->name, name_len);
+	if (ret) {
+		goto end;
+	}
+
+	size_before_location = payload->buffer.size;
+
+	ret = lttng_kernel_function_location_serialize(kfunction->location, payload);
+	if (ret < 0) {
+		goto end;
+	}
+
+	/* Update the header regarding the function size. */
+	header = (struct lttng_event_rule_kernel_function_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_function_is_equal(const struct lttng_event_rule *_a,
+		const struct lttng_event_rule *_b)
+{
+	bool is_equal = false;
+	struct lttng_event_rule_kernel_function *a, *b;
+
+	a = container_of(_a, struct lttng_event_rule_kernel_function, parent);
+	b = container_of(_b, struct lttng_event_rule_kernel_function, parent);
+
+	/* Quick checks */
+	if (!!a->name != !!b->name) {
+		goto end;
+	}
+
+	/* Long check */
+	assert(a->name);
+	assert(b->name);
+	if (strcmp(a->name, b->name)) {
+		goto end;
+	}
+
+	is_equal = lttng_kernel_function_location_is_equal(
+			a->location, b->location);
+end:
+	return is_equal;
+}
+
+static enum lttng_error_code lttng_event_rule_kernel_function_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_function_get_filter(
+		const struct lttng_event_rule *rule)
+{
+	/* Not supported. */
+	return NULL;
+}
+
+static const struct lttng_bytecode *
+lttng_event_rule_kernel_function_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_function_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_function_hash(
+		const struct lttng_event_rule *rule)
+{
+	unsigned long hash;
+	struct lttng_event_rule_kernel_function *krule =
+			container_of(rule, typeof(*krule), parent);
+
+	hash = hash_key_ulong((void *) LTTNG_EVENT_RULE_TYPE_KERNEL_FUNCTION,
+			lttng_ht_seed);
+	hash ^= hash_key_str(krule->name, lttng_ht_seed);
+	hash ^= lttng_kernel_function_location_hash(krule->location);
+
+	return hash;
+}
+
+static
+int kernel_function_set_location(
+		struct lttng_event_rule_kernel_function *kfunction,
+		const struct lttng_kernel_function_location *location)
+{
+	int ret;
+	struct lttng_kernel_function_location *location_copy = NULL;
+
+	if (!kfunction || !location || kfunction->location) {
+		ret = -1;
+		goto end;
+	}
+
+	location_copy = lttng_kernel_function_location_copy(location);
+	if (!location_copy) {
+		ret = -1;
+		goto end;
+	}
+
+	kfunction->location = location_copy;
+	location_copy = NULL;
+	ret = 0;
+end:
+	lttng_kernel_function_location_destroy(location_copy);
+	return ret;
+}
+
+struct lttng_event_rule *lttng_event_rule_kernel_function_create(
+		const struct lttng_kernel_function_location *location)
+{
+	struct lttng_event_rule *rule = NULL;
+	struct lttng_event_rule_kernel_function *krule;
+
+	krule = zmalloc(sizeof(struct lttng_event_rule_kernel_function));
+	if (!krule) {
+		goto end;
+	}
+
+	rule = &krule->parent;
+	lttng_event_rule_init(&krule->parent, LTTNG_EVENT_RULE_TYPE_KERNEL_FUNCTION);
+	krule->parent.validate = lttng_event_rule_kernel_function_validate;
+	krule->parent.serialize = lttng_event_rule_kernel_function_serialize;
+	krule->parent.equal = lttng_event_rule_kernel_function_is_equal;
+	krule->parent.destroy = lttng_event_rule_kernel_function_destroy;
+	krule->parent.generate_filter_bytecode =
+			lttng_event_rule_kernel_function_generate_filter_bytecode;
+	krule->parent.get_filter = lttng_event_rule_kernel_function_get_filter;
+	krule->parent.get_filter_bytecode =
+			lttng_event_rule_kernel_function_get_filter_bytecode;
+	krule->parent.generate_exclusions =
+			lttng_event_rule_kernel_function_generate_exclusions;
+	krule->parent.hash = lttng_event_rule_kernel_function_hash;
+
+	if (kernel_function_set_location(krule, location)) {
+		lttng_event_rule_destroy(rule);
+		rule = NULL;
+	}
+
+end:
+	return rule;
+}
+
+LTTNG_HIDDEN
+ssize_t lttng_event_rule_kernel_function_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_function_comm *kfunction_comm;
+	const char *name;
+	struct lttng_buffer_view current_buffer_view;
+	struct lttng_event_rule *rule = NULL;
+	struct lttng_kernel_function_location *location = NULL;
+
+	if (!_event_rule) {
+		ret = -1;
+		goto end;
+	}
+
+	current_buffer_view = lttng_buffer_view_from_view(
+			&view->buffer, offset, sizeof(*kfunction_comm));
+	if (!lttng_buffer_view_is_valid(&current_buffer_view)) {
+		ERR("Failed to initialize from malformed event rule kfunction: buffer too short to contain header.");
+		ret = -1;
+		goto end;
+	}
+
+	kfunction_comm = (typeof(kfunction_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,
+						kfunction_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,
+				kfunction_comm->name_len)) {
+			ret = -1;
+			goto end;
+		}
+	}
+
+	/* Skip after the name. */
+	offset += kfunction_comm->name_len;
+
+	/* Map the kernel function location. */
+	{
+		struct lttng_payload_view current_payload_view =
+				lttng_payload_view_from_view(view, offset,
+						kfunction_comm->location_len);
+
+		if (!lttng_payload_view_is_valid(&current_payload_view)) {
+			ret = -1;
+			goto end;
+		}
+
+		ret = lttng_kernel_function_location_create_from_payload(
+				&current_payload_view, &location);
+		if (ret < 0) {
+			ret = -1;
+			goto end;
+		}
+	}
+
+	if (ret != kfunction_comm->location_len) {
+		ret = -1;
+		goto end;
+	}
+
+	/* Skip after the location */
+	offset += kfunction_comm->location_len;
+
+	rule = lttng_event_rule_kernel_function_create(location);
+	if (!rule) {
+		ERR("Failed to create event rule kfunction.");
+		ret = -1;
+		goto end;
+	}
+
+	status = lttng_event_rule_kernel_function_set_event_name(rule, name);
+	if (status != LTTNG_EVENT_RULE_STATUS_OK) {
+		ERR("Failed to set event rule kfunction name.");
+		ret = -1;
+		goto end;
+	}
+
+	*_event_rule = rule;
+	rule = NULL;
+	ret = offset;
+end:
+	lttng_kernel_function_location_destroy(location);
+	lttng_event_rule_destroy(rule);
+	return ret;
+}
+
+enum lttng_event_rule_status lttng_event_rule_kernel_function_get_location(
+		const struct lttng_event_rule *rule,
+		const struct lttng_kernel_function_location **location)
+{
+	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
+	struct lttng_event_rule_kernel_function *kfunction;
+
+	if (!rule || !IS_KERNEL_FUNCTION_EVENT_RULE(rule) || !location) {
+		status = LTTNG_EVENT_RULE_STATUS_INVALID;
+		goto end;
+	}
+
+	kfunction = container_of(rule, struct lttng_event_rule_kernel_function, parent);
+	*location = kfunction->location;
+
+	if (!*location) {
+		status = LTTNG_EVENT_RULE_STATUS_UNSET;
+		goto end;
+	}
+
+end:
+	return status;
+}
+
+enum lttng_event_rule_status lttng_event_rule_kernel_function_set_event_name(
+		struct lttng_event_rule *rule, const char *name)
+{
+	char *name_copy = NULL;
+	struct lttng_event_rule_kernel_function *kfunction;
+	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
+
+	if (!rule || !IS_KERNEL_FUNCTION_EVENT_RULE(rule) || !name ||
+			strlen(name) == 0) {
+		status = LTTNG_EVENT_RULE_STATUS_INVALID;
+		goto end;
+	}
+
+	kfunction = container_of(rule, struct lttng_event_rule_kernel_function, parent);
+	name_copy = strdup(name);
+	if (!name_copy) {
+		status = LTTNG_EVENT_RULE_STATUS_ERROR;
+		goto end;
+	}
+
+	free(kfunction->name);
+
+	kfunction->name = name_copy;
+	name_copy = NULL;
+end:
+	return status;
+}
+
+enum lttng_event_rule_status lttng_event_rule_kernel_function_get_event_name(
+		const struct lttng_event_rule *rule, const char **name)
+{
+	struct lttng_event_rule_kernel_function *kfunction;
+	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
+
+	if (!rule || !IS_KERNEL_FUNCTION_EVENT_RULE(rule) || !name) {
+		status = LTTNG_EVENT_RULE_STATUS_INVALID;
+		goto end;
+	}
+
+	kfunction = container_of(rule, struct lttng_event_rule_kernel_function, parent);
+	if (!kfunction->name) {
+		status = LTTNG_EVENT_RULE_STATUS_UNSET;
+		goto end;
+	}
+
+	*name = kfunction->name;
+end:
+	return status;
+}