mirror of
https://github.com/falcosecurity/falco.git
synced 2025-06-18 02:57:41 +00:00
4a73ef8824
In places where a second rule definition might replace, append to, or replace items from a base rule, ensure that the source of the second rule definiton matches the first. This already existed for defines, but for other changes. There was a bug where a second definition might exist for a different source, but the additional rule was used anyway. This now returns the same error for these other changes e.g. "Rule has been re-defined..." as define. Signed-off-by: Mark Stemm <mark.stemm@gmail.com>
349 lines
11 KiB
C++
349 lines
11 KiB
C++
// SPDX-License-Identifier: Apache-2.0
|
|
/*
|
|
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 <string>
|
|
#include <libsinsp/version.h>
|
|
|
|
#include "falco_engine.h"
|
|
#include "rule_loader_collector.h"
|
|
#include "rule_loading_messages.h"
|
|
|
|
#define THROW(cond, err, ctx) \
|
|
{ \
|
|
if((cond)) { \
|
|
throw rule_loader::rule_load_exception(falco::load_result::LOAD_ERR_VALIDATE, \
|
|
(err), \
|
|
(ctx)); \
|
|
} \
|
|
}
|
|
|
|
static inline bool is_operator_defined(const std::string& op) {
|
|
auto ops = libsinsp::filter::parser::supported_operators();
|
|
return find(ops.begin(), ops.end(), op) != ops.end();
|
|
}
|
|
|
|
template<typename T>
|
|
static inline void define_info(indexed_vector<T>& infos, T& info, uint32_t id) {
|
|
auto prev = infos.at(info.name);
|
|
if(prev) {
|
|
info.index = prev->index;
|
|
info.visibility = id;
|
|
*prev = info;
|
|
} else {
|
|
info.index = id;
|
|
info.visibility = id;
|
|
infos.insert(info, info.name);
|
|
}
|
|
}
|
|
|
|
template<typename T, typename U>
|
|
static inline void append_info(T* prev, U& info, uint32_t id) {
|
|
prev->visibility = id;
|
|
}
|
|
|
|
template<typename T, typename U>
|
|
static inline void replace_info(T* prev, U& info, uint32_t id) {
|
|
prev->visibility = id;
|
|
}
|
|
|
|
static void validate_exception_info(const falco_source* source,
|
|
rule_loader::rule_exception_info& ex) {
|
|
if(ex.fields.is_list) {
|
|
if(!ex.comps.is_valid()) {
|
|
ex.comps.is_list = true;
|
|
for(size_t i = 0; i < ex.fields.items.size(); i++) {
|
|
ex.comps.items.push_back(rule_loader::rule_exception_info::entry("="));
|
|
}
|
|
}
|
|
THROW(ex.fields.items.size() != ex.comps.items.size(),
|
|
"Fields and comps lists must have equal length",
|
|
ex.ctx);
|
|
for(const auto& v : ex.comps.items) {
|
|
THROW(!is_operator_defined(v.item),
|
|
std::string("'") + v.item + "' is not a supported comparison operator",
|
|
ex.ctx);
|
|
}
|
|
if(source) {
|
|
for(const auto& v : ex.fields.items) {
|
|
THROW(!source->is_valid_lhs_field(v.item),
|
|
std::string("'") + v.item + "' is not a supported filter field",
|
|
ex.ctx);
|
|
}
|
|
}
|
|
} else {
|
|
if(!ex.comps.is_valid()) {
|
|
ex.comps.is_list = false;
|
|
ex.comps.item = "in";
|
|
}
|
|
THROW(ex.comps.is_list, "Fields and comps must both be strings", ex.ctx);
|
|
THROW((ex.comps.item != "in" && ex.comps.item != "pmatch" && ex.comps.item != "intersects"),
|
|
"When fields is a single value, comps must be one of (in, pmatch, intersects)",
|
|
ex.ctx);
|
|
if(source) {
|
|
THROW(!source->is_valid_lhs_field(ex.fields.item),
|
|
std::string("'") + ex.fields.item + "' is not a supported filter field",
|
|
ex.ctx);
|
|
}
|
|
}
|
|
}
|
|
|
|
void rule_loader::collector::clear() {
|
|
m_cur_index = 0;
|
|
m_rule_infos.clear();
|
|
m_list_infos.clear();
|
|
m_macro_infos.clear();
|
|
m_required_plugin_versions.clear();
|
|
}
|
|
|
|
const std::vector<rule_loader::plugin_version_info::requirement_alternatives>&
|
|
rule_loader::collector::required_plugin_versions() const {
|
|
return m_required_plugin_versions;
|
|
}
|
|
|
|
const rule_loader::engine_version_info& rule_loader::collector::required_engine_version() const {
|
|
return m_required_engine_version;
|
|
}
|
|
|
|
const indexed_vector<rule_loader::list_info>& rule_loader::collector::lists() const {
|
|
return m_list_infos;
|
|
}
|
|
|
|
const indexed_vector<rule_loader::macro_info>& rule_loader::collector::macros() const {
|
|
return m_macro_infos;
|
|
}
|
|
|
|
const indexed_vector<rule_loader::rule_info>& rule_loader::collector::rules() const {
|
|
return m_rule_infos;
|
|
}
|
|
|
|
void rule_loader::collector::define(configuration& cfg, engine_version_info& info) {
|
|
auto v = falco_engine::engine_version();
|
|
THROW(!v.compatible_with(info.version),
|
|
"Rules require engine version " + info.version.as_string() + ", but engine version is " +
|
|
v.as_string(),
|
|
info.ctx);
|
|
|
|
// Store max required_engine_version
|
|
if(m_required_engine_version.version < info.version) {
|
|
m_required_engine_version = info;
|
|
}
|
|
}
|
|
|
|
void rule_loader::collector::define(configuration& cfg, plugin_version_info& info) {
|
|
std::unordered_set<std::string> plugin_names;
|
|
for(const auto& req : info.alternatives) {
|
|
sinsp_version plugin_version(req.version);
|
|
THROW(!plugin_version.is_valid(),
|
|
"Invalid required version '" + req.version + "' for plugin '" + req.name + "'",
|
|
info.ctx);
|
|
THROW(plugin_names.find(req.name) != plugin_names.end(),
|
|
"Defined multiple alternative version requirements for plugin '" + req.name + "'",
|
|
info.ctx);
|
|
plugin_names.insert(req.name);
|
|
}
|
|
m_required_plugin_versions.push_back(info.alternatives);
|
|
}
|
|
|
|
void rule_loader::collector::define(configuration& cfg, list_info& info) {
|
|
define_info(m_list_infos, info, m_cur_index++);
|
|
}
|
|
|
|
void rule_loader::collector::append(configuration& cfg, list_info& info) {
|
|
auto prev = m_list_infos.at(info.name);
|
|
THROW(!prev, ERROR_NO_PREVIOUS_LIST, info.ctx);
|
|
prev->items.insert(prev->items.end(), info.items.begin(), info.items.end());
|
|
append_info(prev, info, m_cur_index++);
|
|
}
|
|
|
|
void rule_loader::collector::define(configuration& cfg, macro_info& info) {
|
|
define_info(m_macro_infos, info, m_cur_index++);
|
|
}
|
|
|
|
void rule_loader::collector::append(configuration& cfg, macro_info& info) {
|
|
auto prev = m_macro_infos.at(info.name);
|
|
THROW(!prev, ERROR_NO_PREVIOUS_MACRO, info.ctx);
|
|
prev->cond += " ";
|
|
prev->cond += info.cond;
|
|
append_info(prev, info, m_cur_index++);
|
|
}
|
|
|
|
void rule_loader::collector::define(configuration& cfg, rule_info& info) {
|
|
auto prev = find_prev_rule(info);
|
|
(void)prev;
|
|
|
|
const auto* source = cfg.sources.at(info.source);
|
|
if(!source) {
|
|
info.unknown_source = true;
|
|
cfg.res->add_warning(falco::load_result::LOAD_UNKNOWN_SOURCE,
|
|
"Unknown source " + info.source + ", skipping",
|
|
info.ctx);
|
|
}
|
|
for(auto& ex : info.exceptions) {
|
|
THROW(!ex.fields.is_valid(),
|
|
"Rule exception item must have fields property with a list of fields",
|
|
ex.ctx);
|
|
validate_exception_info(source, ex);
|
|
}
|
|
|
|
define_info(m_rule_infos, info, m_cur_index++);
|
|
}
|
|
|
|
void rule_loader::collector::append(configuration& cfg, rule_update_info& info) {
|
|
auto prev = find_prev_rule(info);
|
|
|
|
THROW(!prev, ERROR_NO_PREVIOUS_RULE_APPEND, info.ctx);
|
|
THROW(!info.has_any_value(),
|
|
"Appended rule must have exceptions or condition property",
|
|
// "Appended rule must have at least one field that can be appended to", // TODO replace
|
|
// with this and update testing
|
|
info.ctx);
|
|
|
|
// note: source can be nullptr in case we've collected a
|
|
// rule for which the source is unknown
|
|
const falco_source* source = nullptr;
|
|
if(!prev->unknown_source) {
|
|
// note: if the source is not unknown, this should not return nullptr
|
|
source = cfg.sources.at(prev->source);
|
|
THROW(!source, std::string("Unknown source ") + prev->source, info.ctx);
|
|
}
|
|
|
|
if(info.cond.has_value() && !info.cond->empty()) {
|
|
prev->cond += " ";
|
|
prev->cond += *info.cond;
|
|
}
|
|
|
|
if(info.output.has_value() && !info.output->empty()) {
|
|
prev->output += " ";
|
|
prev->output += *info.output;
|
|
}
|
|
|
|
if(info.desc.has_value() && !info.desc->empty()) {
|
|
prev->desc += " ";
|
|
prev->desc += *info.desc;
|
|
}
|
|
|
|
if(info.tags.has_value()) {
|
|
for(auto& tag : *info.tags) {
|
|
prev->tags.insert(tag);
|
|
}
|
|
}
|
|
|
|
if(info.exceptions.has_value()) {
|
|
for(auto& ex : *info.exceptions) {
|
|
auto prev_ex = find_if(
|
|
prev->exceptions.begin(),
|
|
prev->exceptions.end(),
|
|
[&ex](const rule_loader::rule_exception_info& i) { return i.name == ex.name; });
|
|
if(prev_ex == prev->exceptions.end()) {
|
|
THROW(!ex.fields.is_valid(),
|
|
"Rule exception must have fields property with a list of fields",
|
|
ex.ctx);
|
|
THROW(ex.values.empty(),
|
|
"Rule exception must have values property with a list of values",
|
|
ex.ctx);
|
|
validate_exception_info(source, ex);
|
|
prev->exceptions.push_back(ex);
|
|
} else {
|
|
THROW(ex.fields.is_valid(),
|
|
"Can not append exception fields to existing exception, only values",
|
|
ex.ctx);
|
|
THROW(ex.comps.is_valid(),
|
|
"Can not append exception comps to existing exception, only values",
|
|
ex.ctx);
|
|
prev_ex->values.insert(prev_ex->values.end(), ex.values.begin(), ex.values.end());
|
|
}
|
|
}
|
|
}
|
|
|
|
append_info(prev, info, m_cur_index++);
|
|
}
|
|
|
|
void rule_loader::collector::selective_replace(configuration& cfg, rule_update_info& info) {
|
|
auto prev = find_prev_rule(info);
|
|
|
|
THROW(!prev, ERROR_NO_PREVIOUS_RULE_REPLACE, info.ctx);
|
|
THROW(!info.has_any_value(),
|
|
"The rule must have at least one field that can be replaced",
|
|
info.ctx);
|
|
|
|
// note: source can be nullptr in case we've collected a
|
|
// rule for which the source is unknown
|
|
const falco_source* source = nullptr;
|
|
if(!prev->unknown_source) {
|
|
// note: if the source is not unknown, this should not return nullptr
|
|
source = cfg.sources.at(prev->source);
|
|
THROW(!source, std::string("Unknown source ") + prev->source, info.ctx);
|
|
}
|
|
|
|
if(info.cond.has_value()) {
|
|
prev->cond = *info.cond;
|
|
}
|
|
|
|
if(info.output.has_value()) {
|
|
prev->output = *info.output;
|
|
}
|
|
|
|
if(info.desc.has_value()) {
|
|
prev->desc = *info.desc;
|
|
}
|
|
|
|
if(info.tags.has_value()) {
|
|
prev->tags = *info.tags;
|
|
}
|
|
|
|
if(info.exceptions.has_value()) {
|
|
prev->exceptions = *info.exceptions;
|
|
}
|
|
|
|
if(info.priority.has_value()) {
|
|
prev->priority = *info.priority;
|
|
}
|
|
|
|
if(info.enabled.has_value()) {
|
|
prev->enabled = *info.enabled;
|
|
}
|
|
|
|
if(info.warn_evttypes.has_value()) {
|
|
prev->warn_evttypes = *info.warn_evttypes;
|
|
}
|
|
|
|
if(info.skip_if_unknown_filter.has_value()) {
|
|
prev->skip_if_unknown_filter = *info.skip_if_unknown_filter;
|
|
}
|
|
|
|
replace_info(prev, info, m_cur_index++);
|
|
}
|
|
|
|
template<typename ruleInfo>
|
|
rule_loader::rule_info* rule_loader::collector::find_prev_rule(ruleInfo& info) {
|
|
auto ret = m_rule_infos.at(info.name);
|
|
|
|
// Throw an error if both the original rule and current rule
|
|
// have the same name and explicitly have different sources.
|
|
THROW(ret && (ret->source != "" && info.source != "" && ret->source != info.source),
|
|
"Rule has been re-defined with a different source",
|
|
info.ctx);
|
|
|
|
return ret;
|
|
}
|
|
|
|
void rule_loader::collector::enable(configuration& cfg, rule_info& info) {
|
|
auto prev = m_rule_infos.at(info.name);
|
|
THROW(!prev, "Rule has 'enabled' key but no rule by that name already exists", info.ctx);
|
|
prev->enabled = info.enabled;
|
|
}
|