chore(userspace/engine): renamings and code polishing in rule_loader and rule_reader

Signed-off-by: Jason Dellaluce <jasondellaluce@gmail.com>
This commit is contained in:
Jason Dellaluce 2022-04-14 09:21:45 +00:00 committed by poiana
parent e1a5427874
commit f638706ba3
5 changed files with 118 additions and 113 deletions

View File

@ -150,33 +150,33 @@ void falco_engine::load_rules(const string &rules_content, bool verbose, bool al
void falco_engine::load_rules(const string &rules_content, bool verbose, bool all_events, uint64_t &required_engine_version)
{
rule_loader::context ctx(rules_content);
ctx.engine = this;
ctx.min_priority = m_min_priority;
ctx.output_extra = m_extra;
ctx.replace_output_container_info = m_replace_container_info;
rule_loader::configuration cfg(rules_content);
cfg.engine = this;
cfg.min_priority = m_min_priority;
cfg.output_extra = m_extra;
cfg.replace_output_container_info = m_replace_container_info;
std::ostringstream os;
rule_reader reader;
bool success = reader.load(ctx, m_rule_loader);
bool success = reader.load(cfg, m_rule_loader);
if (success)
{
clear_filters();
m_rules.clear();
success = m_rule_loader.compile(ctx, m_rules);
success = m_rule_loader.compile(cfg, m_rules);
}
if (!ctx.errors.empty())
if (!cfg.errors.empty())
{
os << ctx.errors.size() << " errors:" << std::endl;
for(auto &err : ctx.errors)
os << cfg.errors.size() << " errors:" << std::endl;
for(auto &err : cfg.errors)
{
os << err << std::endl;
}
}
if (!ctx.warnings.empty())
if (!cfg.warnings.empty())
{
os << ctx.warnings.size() << " warnings:" << std::endl;
for(auto &warn : ctx.warnings)
os << cfg.warnings.size() << " warnings:" << std::endl;
for(auto &warn : cfg.warnings)
{
os << warn << std::endl;
}

View File

@ -36,7 +36,7 @@ static void quote_item(string& e)
}
}
static void paren_item(std::string& e)
static void paren_item(string& e)
{
if(e[0] != '(')
{
@ -44,7 +44,8 @@ static void paren_item(std::string& e)
}
}
static bool is_field_defined(falco_engine *engine, string source, string field)
static bool is_field_defined(
falco_engine *engine, const string& source, string field)
{
auto factory = engine->get_filter_factory(source);
if(factory)
@ -60,7 +61,7 @@ static bool is_field_defined(falco_engine *engine, string source, string field)
}
// todo(jasondellaluce): add an helper in libsinsp for this
static bool is_operator_defined(std::string op)
static bool is_operator_defined(const string& op)
{
static vector<string> ops = {"=", "==", "!=", "<=", ">=", "<", ">",
"contains", "icontains", "bcontains", "glob", "bstartswith",
@ -69,7 +70,7 @@ static bool is_operator_defined(std::string op)
}
// todo(jasondellaluce): add an helper in libsinsp for this
static bool is_operator_for_list(std::string op)
static bool is_operator_for_list(const string& op)
{
return op == "in" || op == "intersects" || op == "pmatch";
}
@ -90,7 +91,6 @@ static bool is_format_valid(
}
}
template <typename T>
static inline void define_info(indexed_vector<T>& infos, T& info, uint32_t id)
{
@ -113,11 +113,11 @@ template <typename T>
static inline void append_info(T* prev, T& info, uint32_t id)
{
prev->visibility = id;
prev->context.append(info.context);
prev->ctx.append(info.ctx);
}
static void validate_exception_info(
rule_loader::context& ctx,
rule_loader::configuration& cfg,
rule_loader::rule_exception_info &ex,
const string& source)
{
@ -142,7 +142,7 @@ static void validate_exception_info(
}
for (auto &v : ex.fields.items)
{
THROW(!is_field_defined(ctx.engine, source, v.item),
THROW(!is_field_defined(cfg.engine, source, v.item),
"Rule exception item " + ex.name + ": field name "
+ v.item + " is not a supported filter field");
}
@ -159,14 +159,14 @@ static void validate_exception_info(
THROW(!is_operator_defined(ex.comps.item),
"Rule exception item " + ex.name + ": comparison operator "
+ ex.comps.item + " is not a supported comparison operator");
THROW(!is_field_defined(ctx.engine, source, ex.fields.item),
THROW(!is_field_defined(cfg.engine, source, ex.fields.item),
"Rule exception item " + ex.name + ": field name "
+ ex.fields.item + " is not a supported filter field");
}
}
static void build_rule_exception_infos(
vector<rule_loader::rule_exception_info> exceptions,
vector<rule_loader::rule_exception_info>& exceptions,
set<string>& exception_fields,
string& condition)
{
@ -370,8 +370,11 @@ static shared_ptr<ast::expr> parse_condition(
}
static shared_ptr<gen_event_filter> compile_condition(
falco_engine* engine, uint32_t id, shared_ptr<ast::expr> cnd,
string src, string& err)
falco_engine* engine,
uint32_t id,
shared_ptr<ast::expr> cnd,
string src,
string& err)
{
try
{
@ -392,18 +395,20 @@ static shared_ptr<gen_event_filter> compile_condition(
return nullptr;
}
void apply_output_substitutions(rule_loader::context ctx, string& out)
static void apply_output_substitutions(
rule_loader::configuration& cfg,
string& out)
{
if (out.find(s_container_info_fmt) != string::npos)
{
if (ctx.replace_output_container_info)
if (cfg.replace_output_container_info)
{
out = replace(out, s_container_info_fmt, ctx.output_extra);
out = replace(out, s_container_info_fmt, cfg.output_extra);
return;
}
out = replace(out, s_container_info_fmt, s_default_extra_fmt);
}
out += ctx.output_extra.empty() ? "" : " " + ctx.output_extra;
out += cfg.output_extra.empty() ? "" : " " + cfg.output_extra;
}
void rule_loader::clear()
@ -443,24 +448,24 @@ bool rule_loader::is_plugin_compatible(
return true;
}
void rule_loader::define(context& ctx, engine_version_info& info)
void rule_loader::define(configuration& cfg, engine_version_info& info)
{
auto v = falco_engine::engine_version();
THROW(v < info.version, "Rules require engine version "
+ to_string(info.version) + ", but engine version is " + to_string(v));
}
void rule_loader::define(context& ctx, plugin_version_info& info)
void rule_loader::define(configuration& cfg, plugin_version_info& info)
{
m_required_plugin_versions[info.name].insert(info.version);
}
void rule_loader::define(context& ctx, list_info& info)
void rule_loader::define(configuration& cfg, list_info& info)
{
define_info(m_list_infos, info, m_cur_index++);
}
void rule_loader::append(context& ctx, list_info& info)
void rule_loader::append(configuration& cfg, list_info& info)
{
auto prev = m_list_infos.at(info.name);
THROW(!prev, "List " + info.name +
@ -469,11 +474,11 @@ void rule_loader::append(context& ctx, list_info& info)
append_info(prev, info, m_cur_index++);
}
void rule_loader::define(context& ctx, macro_info& info)
void rule_loader::define(configuration& cfg, macro_info& info)
{
if (!ctx.engine->is_source_valid(info.source))
if (!cfg.engine->is_source_valid(info.source))
{
ctx.warnings.push_back("Macro " + info.name
cfg.warnings.push_back("Macro " + info.name
+ ": warning (unknown-source): unknown source "
+ info.source + ", skipping");
return;
@ -481,7 +486,7 @@ void rule_loader::define(context& ctx, macro_info& info)
define_info(m_macro_infos, info, m_cur_index++);
}
void rule_loader::append(context& ctx, macro_info& info)
void rule_loader::append(configuration& cfg, macro_info& info)
{
auto prev = m_macro_infos.at(info.name);
THROW(!prev, "Macro " + info.name
@ -491,11 +496,11 @@ void rule_loader::append(context& ctx, macro_info& info)
append_info(prev, info, m_cur_index++);
}
void rule_loader::define(context& ctx, rule_info& info)
void rule_loader::define(configuration& cfg, rule_info& info)
{
if (!ctx.engine->is_source_valid(info.source))
if (!cfg.engine->is_source_valid(info.source))
{
ctx.warnings.push_back("Rule " + info.name
cfg.warnings.push_back("Rule " + info.name
+ ": warning (unknown-source): unknown source "
+ info.source + ", skipping");
return;
@ -509,13 +514,13 @@ void rule_loader::define(context& ctx, rule_info& info)
{
THROW(!ex.fields.is_valid(), "Rule exception item "
+ ex.name + ": must have fields property with a list of fields");
validate_exception_info(ctx, ex, info.source);
validate_exception_info(cfg, ex, info.source);
}
define_info(m_rule_infos, info, m_cur_index++);
}
void rule_loader::append(context& ctx, rule_info& info)
void rule_loader::append(configuration& cfg, rule_info& info)
{
auto prev = m_rule_infos.at(info.name);
THROW(!prev, "Rule " + info.name
@ -540,7 +545,7 @@ void rule_loader::append(context& ctx, rule_info& info)
+ ex.name + ": must have fields property with a list of fields");
THROW(ex.values.empty(), "Rule exception new item "
+ ex.name + ": must have fields property with a list of values");
validate_exception_info(ctx, ex, prev->source);
validate_exception_info(cfg, ex, prev->source);
prev->exceptions.push_back(ex);
}
else
@ -556,7 +561,7 @@ void rule_loader::append(context& ctx, rule_info& info)
append_info(prev, info, m_cur_index++);
}
void rule_loader::enable(context& ctx, rule_info& info)
void rule_loader::enable(configuration& cfg, rule_info& info)
{
auto prev = m_rule_infos.at(info.name);
THROW(!prev, "Rule " + info.name
@ -564,7 +569,7 @@ void rule_loader::enable(context& ctx, rule_info& info)
prev->enabled = info.enabled;
}
void rule_loader::compile_list_infos(context& ctx, indexed_vector<list_info>& out)
void rule_loader::compile_list_infos(configuration& cfg, indexed_vector<list_info>& out)
{
string tmp;
vector<string> used;
@ -598,7 +603,7 @@ void rule_loader::compile_list_infos(context& ctx, indexed_vector<list_info>& ou
}
catch (exception& e)
{
throw falco_exception(list.context.error(e.what()));
throw falco_exception(list.ctx.error(e.what()));
}
}
for (auto &v : used)
@ -609,17 +614,17 @@ void rule_loader::compile_list_infos(context& ctx, indexed_vector<list_info>& ou
// note: there is a visibility ordering between macros
void rule_loader::compile_macros_infos(
context& ctx,
configuration& cfg,
indexed_vector<list_info>& lists,
indexed_vector<macro_info>& out)
{
set<string> used;
mark* info_ctx = NULL;
context* info_ctx = NULL;
try
{
for (auto &m : m_macro_infos)
{
info_ctx = &m.context;
info_ctx = &m.ctx;
macro_info entry = m;
entry.cond_ast = parse_condition(m.cond, lists);
entry.used = false;
@ -627,7 +632,7 @@ void rule_loader::compile_macros_infos(
}
for (auto &m : out)
{
info_ctx = &m.context;
info_ctx = &m.ctx;
resolve_macros(out, m.cond_ast, m.visibility,
"Compilation error when compiling \"" + m.cond + "\": ");
}
@ -640,7 +645,7 @@ void rule_loader::compile_macros_infos(
void rule_loader::compile_rule_infos(
context& ctx,
configuration& cfg,
indexed_vector<list_info>& lists,
indexed_vector<macro_info>& macros,
indexed_vector<falco_rule>& out)
@ -650,7 +655,7 @@ void rule_loader::compile_rule_infos(
{
try
{
if (r.priority > ctx.min_priority)
if (r.priority > cfg.min_priority)
{
continue;
}
@ -668,9 +673,9 @@ void rule_loader::compile_rule_infos(
rule.output = r.output;
if (r.source == falco_common::syscall_source)
{
apply_output_substitutions(ctx, rule.output);
apply_output_substitutions(cfg, rule.output);
}
THROW(!is_format_valid(ctx.engine, r.source, rule.output, err),
THROW(!is_format_valid(cfg.engine, r.source, rule.output, err),
"Invalid output format '" + rule.output + "': '" + err + "'");
@ -681,13 +686,13 @@ void rule_loader::compile_rule_infos(
rule.tags = r.tags;
// note: indexes are 0-based, but 0 is not an acceptable rule_id
auto id = out.insert(rule, rule.name) + 1;
auto filter = compile_condition(ctx.engine, id, ast, rule.source, err);
auto filter = compile_condition(cfg.engine, id, ast, rule.source, err);
if (!filter)
{
if (r.skip_if_unknown_filter
&& err.find("nonexistent field") != string::npos)
{
ctx.warnings.push_back(
cfg.warnings.push_back(
"Rule " + rule.name + ": warning (unknown-field):");
continue;
}
@ -696,28 +701,28 @@ void rule_loader::compile_rule_infos(
throw falco_exception("Rule " + rule.name + ": error " + err);
}
}
ctx.engine->add_filter(filter, rule.name, rule.source, rule.tags);
cfg.engine->add_filter(filter, rule.name, rule.source, rule.tags);
if (rule.source == falco_common::syscall_source && r.warn_evttypes)
{
auto evttypes = filter->evttypes();
if (evttypes.size() == 0 || evttypes.size() > 100)
{
ctx.warnings.push_back(
cfg.warnings.push_back(
"Rule " + rule.name + ": warning (no-evttype):\n" +
+ " matches too many evt.type values.\n"
+ " This has a significant performance penalty.");
}
}
ctx.engine->enable_rule(rule.name, r.enabled);
cfg.engine->enable_rule(rule.name, r.enabled);
}
catch (exception& e)
{
throw falco_exception(r.context.error(e.what()));
throw falco_exception(r.ctx.error(e.what()));
}
}
}
bool rule_loader::compile(context& ctx, indexed_vector<falco_rule>& out)
bool rule_loader::compile(configuration& cfg, indexed_vector<falco_rule>& out)
{
indexed_vector<list_info> lists;
indexed_vector<macro_info> macros;
@ -725,13 +730,13 @@ bool rule_loader::compile(context& ctx, indexed_vector<falco_rule>& out)
// expand all lists, macros, and rules
try
{
compile_list_infos(ctx, lists);
compile_macros_infos(ctx, lists, macros);
compile_rule_infos(ctx, lists, macros, out);
compile_list_infos(cfg, lists);
compile_macros_infos(cfg, lists, macros);
compile_rule_infos(cfg, lists, macros, out);
}
catch (exception& e)
{
ctx.errors.push_back(e.what());
cfg.errors.push_back(e.what());
return false;
}
@ -740,7 +745,7 @@ bool rule_loader::compile(context& ctx, indexed_vector<falco_rule>& out)
{
if (!m.used)
{
ctx.warnings.push_back("macro " + m.name
cfg.warnings.push_back("macro " + m.name
+ " not referred to by any rule/macro");
}
}
@ -748,7 +753,7 @@ bool rule_loader::compile(context& ctx, indexed_vector<falco_rule>& out)
{
if (!l.used)
{
ctx.warnings.push_back("list " + l.name
cfg.warnings.push_back("list " + l.name
+ " not referred to by any rule/macro/list");
}
}

View File

@ -37,7 +37,7 @@ public:
\brief Represents a section of text from which a certain info
struct has been decoded
*/
struct mark
struct context
{
std::string content;
@ -55,7 +55,7 @@ public:
/*!
\brief Appends another text section info to this one
*/
inline void append(mark& m)
inline void append(context& m)
{
content += "\n\n";
content += m.content;
@ -65,9 +65,9 @@ public:
/*!
\brief Contains the info required to load rule definitions
*/
struct context
struct configuration
{
context(const std::string& cont): content(cont) {}
configuration(const std::string& cont): content(cont) {}
const std::string& content;
std::string output_extra;
bool replace_output_container_info;
@ -99,7 +99,7 @@ public:
*/
struct list_info
{
mark context;
context ctx;
bool used;
size_t index;
size_t visibility;
@ -112,7 +112,7 @@ public:
*/
struct macro_info
{
mark context;
context ctx;
bool used;
size_t index;
size_t visibility;
@ -156,7 +156,7 @@ public:
*/
struct rule_info
{
mark context;
context ctx;
size_t index;
size_t visibility;
std::string name;
@ -190,43 +190,43 @@ public:
/*!
\brief Uses the internal state to compile a list of falco_rules
*/
bool compile(context& ctx, indexed_vector<falco_rule>& out);
bool compile(configuration& cfg, indexed_vector<falco_rule>& out);
/*!
\brief Defines an info block. If a similar info block is found
in the internal state (e.g. another rule with same name), then
the previous definition gets overwritten
*/
virtual void define(context& ctx, engine_version_info& info);
virtual void define(context& ctx, plugin_version_info& info);
virtual void define(context& ctx, list_info& info);
virtual void define(context& ctx, macro_info& info);
virtual void define(context& ctx, rule_info& info);
virtual void define(configuration& cfg, engine_version_info& info);
virtual void define(configuration& cfg, plugin_version_info& info);
virtual void define(configuration& cfg, list_info& info);
virtual void define(configuration& cfg, macro_info& info);
virtual void define(configuration& cfg, rule_info& info);
/*!
\brief Appends an info block to an existing one. An exception
is thrown if no existing definition can be matched with the appended
one
*/
virtual void append(context& ctx, list_info& info);
virtual void append(context& ctx, macro_info& info);
virtual void append(context& ctx, rule_info& info);
virtual void append(configuration& cfg, list_info& info);
virtual void append(configuration& cfg, macro_info& info);
virtual void append(configuration& cfg, rule_info& info);
/*!
\brief Updates the 'enabled' flag of an existing definition
*/
virtual void enable(context& ctx, rule_info& info);
virtual void enable(configuration& cfg, rule_info& info);
private:
void compile_list_infos(
context& ctx,
configuration& cfg,
indexed_vector<list_info>& out);
void compile_macros_infos(
context& ctx,
configuration& cfg,
indexed_vector<list_info>& lists,
indexed_vector<macro_info>& out);
void compile_rule_infos(
context& ctx,
configuration& cfg,
indexed_vector<list_info>& lists,
indexed_vector<macro_info>& macros,
indexed_vector<falco_rule>& out);

View File

@ -18,13 +18,13 @@ limitations under the License.
#define THROW(cond, err) { if (cond) { throw falco_exception(err); } }
static rule_loader::mark yaml_get_mark(
static rule_loader::context yaml_get_context(
const string& content,
const vector<YAML::Node>& docs,
vector<YAML::Node>::iterator doc,
YAML::iterator node)
{
rule_loader::mark m;
rule_loader::context m;
YAML::Node item = *node++;
YAML::Node cur_doc = *doc++;
// include the "- " sequence mark
@ -151,17 +151,17 @@ static void read_rule_exceptions(
}
static void read_item(
rule_loader::context& ctx,
rule_loader::configuration& cfg,
rule_loader& loader,
const YAML::Node& item,
const rule_loader::mark& m)
const rule_loader::context& ctx)
{
if (item["required_engine_version"].IsDefined())
{
rule_loader::engine_version_info v;
THROW(!decode_val(item["required_engine_version"], v.version),
"Value of required_engine_version must be a number");
loader.define(ctx, v);
loader.define(cfg, v);
}
else if(item["required_plugin_versions"].IsDefined())
{
@ -175,13 +175,13 @@ static void read_item(
"required_plugin_versions item must have name property");
THROW(!decode_val(plugin["version"], v.version) || v.version.empty(),
"required_plugin_versions item must have version property");
loader.define(ctx, v);
loader.define(cfg, v);
}
}
else if(item["list"].IsDefined())
{
rule_loader::list_info v;
v.context = m;
v.ctx = ctx;
bool append = false;
THROW(!decode_val(item["list"], v.name) || v.name.empty(),
"List name is empty");
@ -189,17 +189,17 @@ static void read_item(
"List must have property items");
if(decode_val(item["append"], append) && append)
{
loader.append(ctx, v);
loader.append(cfg, v);
}
else
{
loader.define(ctx, v);
loader.define(cfg, v);
}
}
else if(item["macro"].IsDefined())
{
rule_loader::macro_info v;
v.context = m;
v.ctx = ctx;
bool append = false;
v.source = falco_common::syscall_source;
THROW(!decode_val(item["macro"], v.name) || v.name.empty(),
@ -209,17 +209,17 @@ static void read_item(
decode_val(item["source"], v.source);
if(decode_val(item["append"], append) && append)
{
loader.append(ctx, v);
loader.append(cfg, v);
}
else
{
loader.define(ctx, v);
loader.define(cfg, v);
}
}
else if(item["rule"].IsDefined())
{
rule_loader::rule_info v;
v.context = m;
v.ctx = ctx;
bool append = false;
v.enabled = true;
v.warn_evttypes = true;
@ -233,7 +233,7 @@ static void read_item(
{
read_rule_exceptions(item["exceptions"], v);
}
loader.append(ctx, v);
loader.append(cfg, v);
}
else
{
@ -246,7 +246,7 @@ static void read_item(
if (!has_defs)
{
THROW(!has_enabled, "Rule must have properties 'condition', 'output', 'desc', and 'priority'");
loader.enable(ctx, v);
loader.enable(cfg, v);
}
else
{
@ -262,26 +262,26 @@ static void read_item(
{
read_rule_exceptions(item["exceptions"], v);
}
loader.define(ctx, v);
loader.define(cfg, v);
}
}
}
else
{
ctx.warnings.push_back("Unknown top level object");
cfg.warnings.push_back("Unknown top level object");
}
}
bool rule_reader::load(rule_loader::context& ctx, rule_loader& loader)
bool rule_reader::load(rule_loader::configuration& cfg, rule_loader& loader)
{
std::vector<YAML::Node> docs;
try
{
docs = YAML::LoadAll(ctx.content);
docs = YAML::LoadAll(cfg.content);
}
catch(const exception& e)
{
ctx.errors.push_back("Could not load YAML file: " + string(e.what()));
cfg.errors.push_back("Could not load YAML file: " + string(e.what()));
return false;
}
@ -291,12 +291,12 @@ bool rule_reader::load(rule_loader::context& ctx, rule_loader& loader)
{
if(!doc->IsMap() && !doc->IsSequence())
{
ctx.errors.push_back("Rules content is not yaml");
cfg.errors.push_back("Rules content is not yaml");
return false;
}
if(!doc->IsSequence())
{
ctx.errors.push_back(
cfg.errors.push_back(
"Rules content is not yaml array of objects");
return false;
}
@ -304,17 +304,17 @@ bool rule_reader::load(rule_loader::context& ctx, rule_loader& loader)
{
if (!it->IsNull())
{
rule_loader::mark m = yaml_get_mark(ctx.content, docs, doc, it);
auto ctx = yaml_get_context(cfg.content, docs, doc, it);
YAML::Node item = *it;
try
{
THROW(!item.IsMap(), "Unexpected element type. "
"Each element should be a yaml associative array.");
read_item(ctx, loader, item, m);
read_item(cfg, loader, item, ctx);
}
catch(const exception& e)
{
ctx.errors.push_back(m.error(e.what()));
cfg.errors.push_back(ctx.error(e.what()));
return false;
}
}

View File

@ -31,5 +31,5 @@ public:
\brief Reads the contents of a ruleset and uses a loader to store
thew new definitions
*/
virtual bool load(rule_loader::context& ctx, rule_loader& loader);
virtual bool load(rule_loader::configuration& cfg, rule_loader& loader);
};