update(cmake): add rules external project for building packages

Signed-off-by: Jason Dellaluce <jasondellaluce@gmail.com>

CMakeLists.txt

@@ -201,7 +201,7 @@ if(NOT MINIMAL_BUILD)
 endif()
 
 # Rules
-add_subdirectory(rules)
+include(rules)
 
 # Dockerfiles
 add_subdirectory(docker)

cmake/modules/rules.cmake

@@ -0,0 +1,91 @@
+#
+# Copyright (C) 2023 The Falco Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
+# the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations under the License.
+#
+
+include(GNUInstallDirs)
+include(ExternalProject)
+
+# falco_rules.yaml
+set(FALCOSECURITY_RULES_FALCO_VERSION "falco-rules-0.1.0")
+set(FALCOSECURITY_RULES_FALCO_CHECKSUM "SHA256=d933c73659366a167a882beed878bc8f32c26f92166d6a23244c2b6cf189ae72")
+set(FALCOSECURITY_RULES_FALCO_PATH "${PROJECT_BINARY_DIR}/falcosecurity-rules-falco-prefix/src/falcosecurity-rules-falco/rules/falco_rules.yaml")
+ExternalProject_Add(
+  falcosecurity-rules-falco
+  URL "https://github.com/falcosecurity/rules/archive/${FALCOSECURITY_RULES_FALCO_VERSION}.tar.gz"
+  URL_HASH "${FALCOSECURITY_RULES_FALCO_CHECKSUM}"
+  CONFIGURE_COMMAND ""
+  BUILD_COMMAND ""
+  INSTALL_COMMAND ""
+  TEST_COMMAND ""
+)
+
+# application_rules.yaml
+set(FALCOSECURITY_RULES_APPLICATION_VERSION "application-rules-0.1.0")
+set(FALCOSECURITY_RULES_APPLICATION_CHECKSUM "SHA256=ae3f41165422e05393831bbc27afab0824d0e41b57bd1cc53f2bd647ae808857")
+set(FALCOSECURITY_RULES_APPLICATION_PATH "${PROJECT_BINARY_DIR}/falcosecurity-rules-application-prefix/src/falcosecurity-rules-application/rules/application_rules.yaml")
+ExternalProject_Add(
+  falcosecurity-rules-application
+  URL "https://github.com/falcosecurity/rules/archive/${FALCOSECURITY_RULES_APPLICATION_VERSION}.tar.gz"
+  URL_HASH "${FALCOSECURITY_RULES_APPLICATION_CHECKSUM}"
+  CONFIGURE_COMMAND ""
+  BUILD_COMMAND ""
+  INSTALL_COMMAND ""
+  TEST_COMMAND ""
+)
+
+# falco_rules.local.yaml
+set(FALCOSECURITY_RULES_LOCAL_PATH "${PROJECT_BINARY_DIR}/falcosecurity-rules-local-prefix/falco_rules.local.yaml")
+file(WRITE "${FALCOSECURITY_RULES_LOCAL_PATH}" "# Your custom rules!\n")
+
+if(NOT DEFINED FALCO_ETC_DIR)
+  set(FALCO_ETC_DIR "${CMAKE_INSTALL_FULL_SYSCONFDIR}/falco")
+endif()
+
+if(NOT DEFINED FALCO_RULES_DEST_FILENAME)
+  set(FALCO_RULES_DEST_FILENAME "falco_rules.yaml")
+  set(FALCO_LOCAL_RULES_DEST_FILENAME "falco_rules.local.yaml")
+  set(FALCO_APP_RULES_DEST_FILENAME "application_rules.yaml")
+endif()
+
+if(DEFINED FALCO_COMPONENT) # Allow a slim version of Falco to be embedded in other projects, intentionally *not* installing all rulesets.
+  install(
+    FILES "${FALCOSECURITY_RULES_FALCO_PATH}"
+    COMPONENT "${FALCO_COMPONENT}"
+    DESTINATION "${FALCO_ETC_DIR}"
+    RENAME "${FALCO_RULES_DEST_FILENAME}")
+
+  install(
+    FILES "${FALCOSECURITY_RULES_LOCAL_PATH}"
+    COMPONENT "${FALCO_COMPONENT}"
+    DESTINATION "${FALCO_ETC_DIR}"
+    RENAME "${FALCO_LOCAL_RULES_DEST_FILENAME}")
+else() # Default Falco installation
+  install(
+    FILES "${FALCOSECURITY_RULES_FALCO_PATH}"
+    DESTINATION "${FALCO_ETC_DIR}"
+    RENAME "${FALCO_RULES_DEST_FILENAME}"
+    COMPONENT "${FALCO_COMPONENT_NAME}")
+
+  install(
+    FILES "${FALCOSECURITY_RULES_LOCAL_PATH}"
+    DESTINATION "${FALCO_ETC_DIR}"
+    RENAME "${FALCO_LOCAL_RULES_DEST_FILENAME}"
+    COMPONENT "${FALCO_COMPONENT_NAME}")
+
+  install(
+    FILES "${FALCOSECURITY_RULES_APPLICATION_PATH}"
+    DESTINATION "${FALCO_ETC_DIR}/rules.available"
+    RENAME "${FALCO_APP_RULES_DEST_FILENAME}"
+    COMPONENT "${FALCO_COMPONENT_NAME}")
+
+  install(DIRECTORY DESTINATION "${FALCO_ETC_DIR}/rules.d" COMPONENT "${FALCO_COMPONENT_NAME}")
+endif()