osquery-1/osquery/core/tables.cpp
Teddy Reed b28c4d8d0f Introduce table options (#2101)
Table options includes a change to the Registry::call API for TablePlugins.
When requesting route information or the 'columns' action, a new 'op' key is included.
2016-05-18 12:23:52 -07:00

332 lines
11 KiB
C++

/*
* Copyright (c) 2014-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
*/
#include <boost/property_tree/json_parser.hpp>
#include <osquery/database.h>
#include <osquery/flags.h>
#include <osquery/logger.h>
#include <osquery/tables.h>
namespace pt = boost::property_tree;
namespace osquery {
FLAG(bool, disable_caching, false, "Disable scheduled query caching");
size_t TablePlugin::kCacheInterval = 0;
size_t TablePlugin::kCacheStep = 0;
const std::map<ColumnType, std::string> kColumnTypeNames = {
{UNKNOWN_TYPE, "UNKNOWN"},
{TEXT_TYPE, "TEXT"},
{INTEGER_TYPE, "INTEGER"},
{BIGINT_TYPE, "BIGINT"},
{UNSIGNED_BIGINT_TYPE, "UNSIGNED BIGINT"},
{DOUBLE_TYPE, "DOUBLE"},
{BLOB_TYPE, "BLOB"},
};
Status TablePlugin::addExternal(const std::string& name,
const PluginResponse& response) {
// Attach the table.
if (response.size() == 0) {
// Invalid table route info.
return Status(1, "Invalid route info");
}
// Use the SQL registry to attach the name/definition.
return Registry::call("sql", "sql", {{"action", "attach"}, {"table", name}});
}
void TablePlugin::removeExternal(const std::string& name) {
// Detach the table name.
Registry::call("sql", "sql", {{"action", "detach"}, {"table", name}});
}
void TablePlugin::setRequestFromContext(const QueryContext& context,
PluginRequest& request) {
pt::ptree tree;
tree.put("limit", context.limit);
// The QueryContext contains a constraint map from column to type information
// and the list of operand/expression constraints applied to that column from
// the query given.
pt::ptree constraints;
for (const auto& constraint : context.constraints) {
pt::ptree child;
child.put("name", constraint.first);
constraint.second.serialize(child);
constraints.push_back(std::make_pair("", child));
}
tree.add_child("constraints", constraints);
// Write the property tree as a JSON string into the PluginRequest.
std::ostringstream output;
try {
pt::write_json(output, tree, false);
} catch (const pt::json_parser::json_parser_error& e) {
// The content could not be represented as JSON.
}
request["context"] = output.str();
}
void TablePlugin::setContextFromRequest(const PluginRequest& request,
QueryContext& context) {
if (request.count("context") == 0) {
return;
}
// Read serialized context from PluginRequest.
pt::ptree tree;
try {
std::stringstream input;
input << request.at("context");
pt::read_json(input, tree);
} catch (const pt::json_parser::json_parser_error& e) {
return;
}
// Set the context limit and deserialize each column constraint list.
context.limit = tree.get<int>("limit", 0);
for (const auto& constraint : tree.get_child("constraints")) {
auto column_name = constraint.second.get<std::string>("name");
context.constraints[column_name].unserialize(constraint.second);
}
}
Status TablePlugin::call(const PluginRequest& request,
PluginResponse& response) {
response.clear();
// TablePlugin API calling requires an action.
if (request.count("action") == 0) {
return Status(1, "Table plugins must include a request action");
}
if (request.at("action") == "generate") {
// The "generate" action runs the table implementation using a PluginRequest
// with optional serialized QueryContext and returns the QueryData results
// as the PluginRequest data.
// Create a fake table implementation for caching.
QueryContext context;
if (request.count("context") > 0) {
setContextFromRequest(request, context);
}
response = generate(context);
} else if (request.at("action") == "columns") {
// The "columns" action returns a PluginRequest filled with column
// information such as name and type.
const auto& column_list = columns();
for (const auto& column : column_list) {
response.push_back({{"name", std::get<0>(column)},
{"type", columnTypeName(std::get<1>(column))},
{"op", INTEGER(std::get<2>(column))}});
}
} else if (request.at("action") == "definition") {
response.push_back({{"definition", columnDefinition()}});
} else {
return Status(1, "Unknown table plugin action: " + request.at("action"));
}
return Status(0, "OK");
}
std::string TablePlugin::columnDefinition() const {
return osquery::columnDefinition(columns());
}
PluginResponse TablePlugin::routeInfo() const {
// Route info consists of only the serialized column information.
PluginResponse response;
for (const auto& column : columns()) {
response.push_back({{"name", std::get<0>(column)},
{"type", columnTypeName(std::get<1>(column))},
{"op", INTEGER(std::get<2>(column))}});
}
return response;
}
bool TablePlugin::isCached(size_t step) {
return (!FLAGS_disable_caching && step < last_cached_ + last_interval_);
}
QueryData TablePlugin::getCache() const {
VLOG(1) << "Retrieving results from cache for table: " << getName();
// Lookup results from database and deserialize.
std::string content;
getDatabaseValue(kQueries, "cache." + getName(), content);
QueryData results;
deserializeQueryDataJSON(content, results);
return results;
}
void TablePlugin::setCache(size_t step,
size_t interval,
const QueryData& results) {
// Serialize QueryData and save to database.
std::string content;
if (!FLAGS_disable_caching && serializeQueryDataJSON(results, content)) {
last_cached_ = step;
last_interval_ = interval;
setDatabaseValue(kQueries, "cache." + getName(), content);
}
}
std::string columnDefinition(const TableColumns& columns) {
std::string statement = "(";
for (size_t i = 0; i < columns.size(); ++i) {
const auto& column = columns.at(i);
statement +=
"`" + std::get<0>(column) + "` " + columnTypeName(std::get<1>(column));
if (i < columns.size() - 1) {
statement += ", ";
}
}
return statement += ")";
}
std::string columnDefinition(const PluginResponse& response) {
TableColumns columns;
for (const auto& column : response) {
columns.push_back(make_tuple(
column.at("name"),
columnTypeName(column.at("type")),
(ColumnOptions)AS_LITERAL(INTEGER_LITERAL, column.at("op"))));
}
return columnDefinition(columns);
}
ColumnType columnTypeName(const std::string& type) {
for (const auto& col : kColumnTypeNames) {
if (col.second == type) {
return col.first;
}
}
return UNKNOWN_TYPE;
}
bool ConstraintList::exists(const ConstraintOperatorFlag ops) const {
if (ops == ANY_OP) {
return (constraints_.size() > 0);
} else {
for (const struct Constraint& c : constraints_) {
if (c.op & ops) {
return true;
}
}
return false;
}
}
bool ConstraintList::matches(const std::string& expr) const {
// Support each SQL affinity type casting.
if (affinity == TEXT_TYPE) {
return literal_matches<TEXT_LITERAL>(expr);
} else if (affinity == INTEGER_TYPE) {
INTEGER_LITERAL lexpr = AS_LITERAL(INTEGER_LITERAL, expr);
return literal_matches<INTEGER_LITERAL>(lexpr);
} else if (affinity == BIGINT_TYPE) {
BIGINT_LITERAL lexpr = AS_LITERAL(BIGINT_LITERAL, expr);
return literal_matches<BIGINT_LITERAL>(lexpr);
} else if (affinity == UNSIGNED_BIGINT_TYPE) {
UNSIGNED_BIGINT_LITERAL lexpr = AS_LITERAL(UNSIGNED_BIGINT_LITERAL, expr);
return literal_matches<UNSIGNED_BIGINT_LITERAL>(lexpr);
} else {
// Unsupported affinity type.
return false;
}
}
template <typename T>
bool ConstraintList::literal_matches(const T& base_expr) const {
bool aggregate = true;
for (size_t i = 0; i < constraints_.size(); ++i) {
T constraint_expr = AS_LITERAL(T, constraints_[i].expr);
if (constraints_[i].op == EQUALS) {
aggregate = aggregate && (base_expr == constraint_expr);
} else if (constraints_[i].op == GREATER_THAN) {
aggregate = aggregate && (base_expr > constraint_expr);
} else if (constraints_[i].op == LESS_THAN) {
aggregate = aggregate && (base_expr < constraint_expr);
} else if (constraints_[i].op == GREATER_THAN_OR_EQUALS) {
aggregate = aggregate && (base_expr >= constraint_expr);
} else if (constraints_[i].op == LESS_THAN_OR_EQUALS) {
aggregate = aggregate && (base_expr <= constraint_expr);
} else {
// Unsupported constraint.
return false;
}
if (!aggregate) {
// Speed up comparison.
return false;
}
}
return true;
}
std::set<std::string> ConstraintList::getAll(ConstraintOperator op) const {
std::set<std::string> set;
for (size_t i = 0; i < constraints_.size(); ++i) {
if (constraints_[i].op == op) {
// TODO: this does not apply a distinct.
set.insert(constraints_[i].expr);
}
}
return set;
}
void ConstraintList::serialize(boost::property_tree::ptree& tree) const {
boost::property_tree::ptree expressions;
for (const auto& constraint : constraints_) {
boost::property_tree::ptree child;
child.put("op", constraint.op);
child.put("expr", constraint.expr);
expressions.push_back(std::make_pair("", child));
}
tree.add_child("list", expressions);
tree.put("affinity", columnTypeName(affinity));
}
void ConstraintList::unserialize(const boost::property_tree::ptree& tree) {
// Iterate through the list of operand/expressions, then set the constraint
// type affinity.
for (const auto& list : tree.get_child("list")) {
Constraint constraint(list.second.get<unsigned char>("op"));
constraint.expr = list.second.get<std::string>("expr");
constraints_.push_back(constraint);
}
affinity = columnTypeName(tree.get<std::string>("affinity", "UNKNOWN"));
}
bool QueryContext::hasConstraint(const std::string& column,
ConstraintOperator op) const {
if (constraints.count(column) == 0) {
return false;
}
return constraints.at(column).exists(op);
}
Status QueryContext::expandConstraints(
const std::string& column,
ConstraintOperator op,
std::set<std::string>& output,
std::function<Status(const std::string& constraint,
std::set<std::string>& output)> predicate) {
for (const auto& constraint : constraints[column].getAll(op)) {
auto status = predicate(constraint, output);
if (!status) {
return status;
}
}
return Status(0);
}
}