--- /dev/null
+/*
+ * Copyright (C) 2019 - Jonathan Rajotte-Julien <jonathan.rajotte-julien@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License, version 2.1 only,
+ * as published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <lttng/constant.h>
+#include <lttng/event-rule/event-rule-internal.h>
+#include <lttng/event-rule/kprobe-internal.h>
+#include <common/macros.h>
+#include <common/error.h>
+#include <common/runas.h>
+#include <assert.h>
+#include <stdio.h>
+#include <ctype.h>
+
+#define IS_KPROBE_EVENT_RULE(rule) ( \
+ lttng_event_rule_get_type(rule) == LTTNG_EVENT_RULE_TYPE_KPROBE \
+ )
+
+#if (LTTNG_SYMBOL_NAME_LEN == 256)
+#define LTTNG_SYMBOL_NAME_LEN_SCANF_IS_A_BROKEN_API "255"
+#endif
+
+static
+void lttng_event_rule_kprobe_destroy(struct lttng_event_rule *rule)
+{
+ struct lttng_event_rule_kprobe *kprobe;
+
+ kprobe = container_of(rule, struct lttng_event_rule_kprobe,
+ parent);
+
+ free(kprobe->name);
+ free(kprobe->probe.symbol_name);
+ free(kprobe);
+}
+
+static
+bool lttng_event_rule_kprobe_validate(
+ const struct lttng_event_rule *rule)
+{
+ bool valid = false;
+ struct lttng_event_rule_kprobe *kprobe;
+
+ if (!rule) {
+ goto end;
+ }
+
+ kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
+
+ /* Required field */
+ if (!kprobe->name) {
+ ERR("Invalid name event rule: a name must be set.");
+ goto end;
+ }
+ if (kprobe->probe.set == LTTNG_DOMAIN_NONE) {
+ ERR("Invalid kprobe event rule: a source must be set.");
+ goto end;
+ }
+
+ valid = true;
+end:
+ return valid;
+}
+
+static
+int lttng_event_rule_kprobe_serialize(
+ const struct lttng_event_rule *rule,
+ struct lttng_dynamic_buffer *buf,
+ int *fd_to_send)
+{
+ int ret;
+ size_t name_len, probe_symbol_name_len;
+ struct lttng_event_rule_kprobe *kprobe;
+ struct lttng_event_rule_kprobe_comm kprobe_comm;
+
+ if (!rule || !IS_KPROBE_EVENT_RULE(rule)) {
+ ret = -1;
+ goto end;
+ }
+
+ DBG("Serializing kprobe event rule");
+ kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
+
+ name_len = strlen(kprobe->name) + 1;
+
+ if (kprobe->probe.symbol_name != NULL) {
+ probe_symbol_name_len = strlen(kprobe->probe.symbol_name) + 1;
+ } else {
+ probe_symbol_name_len = 0;
+ }
+
+ kprobe_comm.name_len = name_len;
+ kprobe_comm.probe_symbol_name_len = probe_symbol_name_len;
+ kprobe_comm.probe_address = kprobe->probe.address;
+ kprobe_comm.probe_offset = kprobe->probe.offset;
+
+ ret = lttng_dynamic_buffer_append(
+ buf, &kprobe_comm, sizeof(kprobe_comm));
+ if (ret) {
+ goto end;
+ }
+ ret = lttng_dynamic_buffer_append(buf, kprobe->name, name_len);
+ if (ret) {
+ goto end;
+ }
+ ret = lttng_dynamic_buffer_append(
+ buf, kprobe->probe.symbol_name, probe_symbol_name_len);
+ if (ret) {
+ goto end;
+ }
+
+ if (fd_to_send) {
+ /* Nothing to send */
+ *fd_to_send = -1;
+ }
+end:
+ return ret;
+}
+
+static
+bool lttng_event_rule_kprobe_is_equal(const struct lttng_event_rule *_a,
+ const struct lttng_event_rule *_b)
+{
+ bool is_equal = false;
+ struct lttng_event_rule_kprobe *a, *b;
+
+ a = container_of(_a, struct lttng_event_rule_kprobe, parent);
+ b = container_of(_b, struct lttng_event_rule_kprobe, parent);
+
+ /* Quick checks */
+ if (!!a->name != !!b->name) {
+ goto end;
+ }
+
+ if (!!a->probe.symbol_name != !!b->probe.symbol_name) {
+ goto end;
+ }
+
+ /* Long check */
+ /* kprobe is invalid if this is not true */
+ /* TODO: validate that a kprobe MUST have a name */
+ assert(a->name);
+ assert(b->name);
+ if (strcmp(a->name, b->name)) {
+ goto end;
+ }
+
+ if (a->probe.symbol_name) {
+ /* Both have symbol name due to previous checks */
+ if (strcmp(a->probe.symbol_name, b->probe.symbol_name)) {
+ goto end;
+ }
+ }
+
+ if (a->probe.offset != b->probe.offset) {
+ goto end;
+ }
+
+ if (a->probe.address != b->probe.address) {
+ goto end;
+ }
+
+ is_equal = true;
+end:
+ return is_equal;
+}
+
+static
+enum lttng_error_code lttng_event_rule_kprobe_populate(struct lttng_event_rule *rule, uid_t uid, gid_t gid)
+{
+ /* Nothing to do */
+ return LTTNG_OK;
+}
+
+static const char *lttng_event_rule_kprobe_get_filter(
+ const struct lttng_event_rule *rule)
+{
+ /* Not supported */
+ return NULL;
+}
+
+static const struct lttng_filter_bytecode *
+lttng_event_rule_kprobe_get_filter_bytecode(const struct lttng_event_rule *rule)
+{
+ /* Not supported */
+ return NULL;
+}
+
+static
+struct lttng_event_exclusion *lttng_event_rule_kprobe_generate_exclusions(struct lttng_event_rule *rule)
+{
+ /* Not supported */
+ return NULL;
+}
+
+struct lttng_event_rule *lttng_event_rule_kprobe_create()
+{
+ struct lttng_event_rule_kprobe *rule;
+
+ rule = zmalloc(sizeof(struct lttng_event_rule_kprobe));
+ if (!rule) {
+ return NULL;
+ }
+
+ lttng_event_rule_init(&rule->parent, LTTNG_EVENT_RULE_TYPE_KPROBE);
+ rule->parent.validate = lttng_event_rule_kprobe_validate;
+ rule->parent.serialize = lttng_event_rule_kprobe_serialize;
+ rule->parent.equal = lttng_event_rule_kprobe_is_equal;
+ rule->parent.destroy = lttng_event_rule_kprobe_destroy;
+ rule->parent.populate = lttng_event_rule_kprobe_populate;
+ rule->parent.get_filter = lttng_event_rule_kprobe_get_filter;
+ rule->parent.get_filter_bytecode = lttng_event_rule_kprobe_get_filter_bytecode;
+ rule->parent.generate_exclusions = lttng_event_rule_kprobe_generate_exclusions;
+ return &rule->parent;
+}
+
+LTTNG_HIDDEN
+ssize_t lttng_event_rule_kprobe_create_from_buffer(
+ const struct lttng_buffer_view *view,
+ struct lttng_event_rule **_event_rule)
+{
+ ssize_t ret, offset = 0;
+ enum lttng_event_rule_status status;
+ const struct lttng_event_rule_kprobe_comm *kprobe_comm;
+ const char *name;
+ const char *probe_symbol_name = NULL;
+ struct lttng_buffer_view current_view;
+ struct lttng_event_rule *rule = NULL;
+ struct lttng_event_rule_kprobe *kprobe = NULL;
+
+ if (!_event_rule) {
+ ret = -1;
+ goto end;
+ }
+
+ if (view->size < sizeof(*kprobe_comm)) {
+ ERR("Failed to initialize from malformed event rule kprobe: buffer too short to contain header");
+ ret = -1;
+ goto end;
+ }
+
+ current_view = lttng_buffer_view_from_view(
+ view, offset, sizeof(*kprobe_comm));
+ kprobe_comm = (typeof(kprobe_comm)) current_view.data;
+ if (!kprobe_comm) {
+ ret = -1;
+ goto end;
+ }
+
+ rule = lttng_event_rule_kprobe_create();
+ if (!rule) {
+ ERR("Failed to create event rule kprobe");
+ ret = -1;
+ goto end;
+ }
+
+ kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
+
+ /* Skip to payload */
+ offset += current_view.size;
+ /* Map the name */
+ current_view = lttng_buffer_view_from_view(
+ view, offset, kprobe_comm->name_len);
+ name = current_view.data;
+ if (!name) {
+ ret = -1;
+ goto end;
+ }
+
+ if (kprobe_comm->name_len == 1 ||
+ name[kprobe_comm->name_len - 1] != '\0' ||
+ strlen(name) != kprobe_comm->name_len - 1) {
+ /*
+ * Check that the name is not NULL, is NULL-terminated, and
+ * does not contain a NULL before the last byte.
+ */
+ ret = -1;
+ goto end;
+ }
+
+ /* Skip after the name */
+ offset += kprobe_comm->name_len;
+ if (!kprobe_comm->probe_symbol_name_len) {
+ goto skip_probe_symbol_name;
+ }
+
+ /* Map the probe_symbol_name */
+ current_view = lttng_buffer_view_from_view(
+ view, offset, kprobe_comm->probe_symbol_name_len);
+ probe_symbol_name = current_view.data;
+ if (!probe_symbol_name) {
+ ret = -1;
+ goto end;
+ }
+
+ if (kprobe_comm->probe_symbol_name_len == 1 ||
+ probe_symbol_name[kprobe_comm->probe_symbol_name_len -
+ 1] != '\0' ||
+ strlen(probe_symbol_name) !=
+ kprobe_comm->probe_symbol_name_len -
+ 1) {
+ /*
+ * Check that the filter expression is not NULL, is
+ * NULL-terminated, and does not contain a NULL before the last
+ * byte.
+ */
+ ret = -1;
+ goto end;
+ }
+
+ /* Skip after the pattern */
+ offset += kprobe_comm->probe_symbol_name_len;
+
+skip_probe_symbol_name:
+
+ status = lttng_event_rule_kprobe_set_name(rule, name);
+ if (status != LTTNG_EVENT_RULE_STATUS_OK) {
+ ERR("Failed to set event rule kprobe name");
+ ret = -1;
+ goto end;
+ }
+ kprobe->probe.offset = kprobe_comm->probe_offset;
+ kprobe->probe.address = kprobe_comm->probe_address;
+ if (probe_symbol_name) {
+ kprobe->probe.symbol_name = strdup(probe_symbol_name);
+ if (!kprobe->probe.symbol_name) {
+ ERR("Failed to set event rule kprobe probe symbol name");
+ ret = -1;
+ goto end;
+ }
+ }
+
+ *_event_rule = rule;
+ rule = NULL;
+ ret = offset;
+end:
+ lttng_event_rule_destroy(rule);
+ return ret;
+}
+
+enum lttng_event_rule_status lttng_event_rule_kprobe_set_source(
+ struct lttng_event_rule *rule, const char *source)
+{
+ enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
+ int match;
+ char s_hex[19];
+ char name[LTTNG_SYMBOL_NAME_LEN];
+ struct lttng_event_rule_kprobe *kprobe;
+
+ /* TODO: support multiple call for this, we must free the symbol name if
+ * that happens !!!
+ */
+
+ if (!source || !IS_KPROBE_EVENT_RULE(rule) || !rule) {
+ status = LTTNG_EVENT_RULE_STATUS_INVALID;
+ goto end;
+ }
+
+ kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
+
+ /* Check for symbol+offset */
+ match = sscanf(source, "%18s[^'+']+%18s", name, s_hex);
+ if (match == 2) {
+ /* TODO double validate termination handling of this */
+ kprobe->probe.symbol_name =
+ strndup(name, LTTNG_SYMBOL_NAME_LEN);
+ if (!kprobe->probe.symbol_name) {
+ status = LTTNG_EVENT_RULE_STATUS_ERROR;
+ goto end;
+ }
+ if (*s_hex == '\0') {
+ status = LTTNG_EVENT_RULE_STATUS_INVALID;
+ goto end;
+ }
+ kprobe->probe.offset = strtoul(s_hex, NULL, 0);
+ kprobe->probe.address = 0;
+ kprobe->probe.set = true;
+ goto end;
+ }
+
+ /* Check for symbol */
+ if (isalpha(name[0]) || name[0] == '_') {
+ match = sscanf(source,
+ "%" LTTNG_SYMBOL_NAME_LEN_SCANF_IS_A_BROKEN_API
+ "s",
+ name);
+ if (match == 1) {
+ /* TODO double validate termination handling of this */
+ kprobe->probe.symbol_name =
+ strndup(name, LTTNG_SYMBOL_NAME_LEN);
+ if (!kprobe->probe.symbol_name) {
+ status = LTTNG_EVENT_RULE_STATUS_ERROR;
+ goto end;
+ }
+ kprobe->probe.offset = 0;
+ kprobe->probe.address = 0;
+ kprobe->probe.set = true;
+ goto end;
+ }
+ }
+
+ /* Check for address */
+ match = sscanf(source, "%18s", s_hex);
+ if (match > 0) {
+ if (*s_hex == '\0') {
+ status = LTTNG_EVENT_RULE_STATUS_INVALID;
+ goto end;
+ }
+ kprobe->probe.address = strtoul(s_hex, NULL, 0);
+ kprobe->probe.offset = 0;
+ kprobe->probe.symbol_name = NULL;
+ kprobe->probe.set = true;
+ goto end;
+ }
+
+ /* No match */
+ status = LTTNG_EVENT_RULE_STATUS_INVALID;
+
+end:
+ return status;
+}
+
+enum lttng_event_rule_status lttng_event_rule_kprobe_set_name(
+ struct lttng_event_rule *rule, const char *name)
+{
+ char *name_copy = NULL;
+ struct lttng_event_rule_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_kprobe, parent);
+ name_copy = strdup(name);
+ if (!name_copy) {
+ status = LTTNG_EVENT_RULE_STATUS_ERROR;
+ goto end;
+ }
+
+ if (kprobe->name) {
+ free(kprobe->name);
+ }
+
+ kprobe->name = name_copy;
+ name_copy = NULL;
+end:
+ return status;
+}
+
+enum lttng_event_rule_status lttng_event_rule_kprobe_get_name(
+ const struct lttng_event_rule *rule, const char **name)
+{
+ struct lttng_event_rule_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_kprobe, parent);
+ if (!kprobe->name) {
+ status = LTTNG_EVENT_RULE_STATUS_UNSET;
+ goto end;
+ }
+
+ *name = kprobe->name;
+end:
+ return status;
+}
+
+LTTNG_HIDDEN
+uint64_t lttng_event_rule_kprobe_get_address(
+ const struct lttng_event_rule *rule)
+{
+ struct lttng_event_rule_kprobe *kprobe;
+
+ assert(rule && IS_KPROBE_EVENT_RULE(rule));
+
+ kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
+
+ return kprobe->probe.address;
+}
+
+LTTNG_HIDDEN
+uint64_t lttng_event_rule_kprobe_get_offset(
+ const struct lttng_event_rule *rule)
+{
+ struct lttng_event_rule_kprobe *kprobe;
+
+ assert(rule && IS_KPROBE_EVENT_RULE(rule));
+
+ kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
+ return kprobe->probe.offset;
+}
+
+LTTNG_HIDDEN
+const char *lttng_event_rule_kprobe_get_symbol_name(
+ const struct lttng_event_rule *rule)
+{
+ struct lttng_event_rule_kprobe *kprobe;
+
+ assert(rule && IS_KPROBE_EVENT_RULE(rule));
+
+ kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
+ return kprobe->probe.symbol_name;
+}
projects / lttng-tools.git / blobdiff