Files
falco/userspace/engine/falco_common.cpp
Vaibhav 22a95796c1 feat(userspace): Add banned.h which includes banned functions.
This defines certain functions as invalid tokens, i.e., when
compiled, the compiler throws an error.

Currently only `strcpy` is included as a banned function.

Fixes #788

Signed-off-by: Vaibhav <vrongmeal@gmail.com>
2020-02-04 17:47:56 +01:00

121 lines
2.7 KiB
C++

/*
Copyright (C) 2019 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 <fstream>
#include "config_falco_engine.h"
#include "falco_common.h"
#include "banned.h"
std::vector<std::string> falco_common::priority_names = {
"Emergency",
"Alert",
"Critical",
"Error",
"Warning",
"Notice",
"Informational",
"Debug"};
falco_common::falco_common()
{
m_ls = lua_open();
if(!m_ls)
{
throw falco_exception("Cannot open lua");
}
luaL_openlibs(m_ls);
}
falco_common::~falco_common()
{
if(m_ls)
{
lua_close(m_ls);
}
}
void falco_common::set_inspector(sinsp *inspector)
{
m_inspector = inspector;
}
void falco_common::init(const char *lua_main_filename, const char *alternate_lua_dir)
{
ifstream is;
string lua_dir = FALCO_ENGINE_LUA_DIR;
string lua_main_path = lua_dir + lua_main_filename;
is.open(lua_main_path);
if (!is.is_open())
{
lua_dir = alternate_lua_dir;
lua_main_path = lua_dir + lua_main_filename;
is.open(lua_main_path);
if (!is.is_open())
{
throw falco_exception("Could not find Falco Lua entrypoint (tried " +
string(FALCO_ENGINE_LUA_DIR) + lua_main_filename + ", " +
string(alternate_lua_dir) + lua_main_filename + ")");
}
}
// Initialize Lua interpreter
add_lua_path(lua_dir);
// Load the main program, which defines all the available functions.
string scriptstr((istreambuf_iterator<char>(is)),
istreambuf_iterator<char>());
if(luaL_loadstring(m_ls, scriptstr.c_str()) || lua_pcall(m_ls, 0, 0, 0))
{
throw falco_exception("Failed to load script " +
lua_main_path + ": " + lua_tostring(m_ls, -1));
}
}
void falco_common::add_lua_path(string &path)
{
string cpath = string(path);
path += "?.lua";
cpath += "?.so";
lua_getglobal(m_ls, "package");
lua_getfield(m_ls, -1, "path");
string cur_path = lua_tostring(m_ls, -1 );
cur_path += ';';
lua_pop(m_ls, 1);
cur_path.append(path.c_str());
lua_pushstring(m_ls, cur_path.c_str());
lua_setfield(m_ls, -2, "path");
lua_getfield(m_ls, -1, "cpath");
string cur_cpath = lua_tostring(m_ls, -1 );
cur_cpath += ';';
lua_pop(m_ls, 1);
cur_cpath.append(cpath.c_str());
lua_pushstring(m_ls, cur_cpath.c_str());
lua_setfield(m_ls, -2, "cpath");
lua_pop(m_ls, 1);
}