+/*
+ * Copyright (C) 2019 Jonathan Rajotte <jonathan.rajotte-julien@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-kprobe-internal.h>
+#include <lttng/kernel-probe.h>
+#include <lttng/kernel-probe-internal.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 */
+ assert(a->name);
+ 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;
+}
+
+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;
+
+ if (kernel_probe_set_location(krule, location)) {
+ lttng_event_rule_destroy(rule);
+ rule = NULL;
+ }
+
+end:
+ return rule;
+}
+
+LTTNG_HIDDEN
+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(¤t_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(¤t_payload_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ name = current_payload_view.buffer.data;
+ if (!lttng_buffer_view_contains_string(
+ ¤t_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(¤t_payload_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_kernel_probe_location_create_from_payload(
+ ¤t_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;
+}
projects / lttng-tools.git / commitdiff
