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#[macro_use]
extern crate error_chain;
#[macro_use]
extern crate log;
extern crate env_logger;
extern crate openvpn_ffi;
extern crate talpid_ipc;
use std::os::raw::{c_int, c_void};
mod processing;
use openvpn_ffi::{OPENVPN_PLUGIN_FUNC_ERROR, OPENVPN_PLUGIN_FUNC_SUCCESS, OpenVpnPluginEvent,
openvpn_plugin_args_func_in, openvpn_plugin_args_func_return,
openvpn_plugin_args_open_in, openvpn_plugin_args_open_return};
use processing::EventProcessor;
error_chain!{
errors {
InitHandleFailed {
description("Unable to initialize event processor")
}
InvalidEventType {
description("Invalid event type constant")
}
ParseEnvFailed {
description("Unable to parse environment variables from OpenVPN")
}
ParseArgsFailed {
description("Unable to parse arguments from OpenVPN")
}
EventProcessingFailed {
description("Failed to process the event")
}
}
}
/// All the OpenVPN events this plugin will register for listening to. Edit this variable to change
/// events.
pub static INTERESTING_EVENTS: &'static [OpenVpnPluginEvent] =
&[OpenVpnPluginEvent::Up, OpenVpnPluginEvent::RoutePredown];
/// Called by OpenVPN when the plugin is first loaded.
/// Used to register which events the plugin wants to listen to (`args.type_mask`). Can also set an
/// arbitrary pointer inside `args.handle` that will then be passed to all subsequent calls to the
/// plugin.
#[no_mangle]
pub extern "C" fn openvpn_plugin_open_v3(_version: c_int,
args: *const openvpn_plugin_args_open_in,
retptr: *mut openvpn_plugin_args_open_return)
-> c_int {
if init_logger().is_err() {
return OPENVPN_PLUGIN_FUNC_ERROR;
}
match openvpn_plugin_open_v3_internal(args, retptr) {
Ok(_) => OPENVPN_PLUGIN_FUNC_SUCCESS,
Err(e) => {
log_error("Unable to initialize plugin", &e);
OPENVPN_PLUGIN_FUNC_ERROR
}
}
}
fn openvpn_plugin_open_v3_internal(args: *const openvpn_plugin_args_open_in,
retptr: *mut openvpn_plugin_args_open_return)
-> Result<()> {
debug!("Initializing plugin");
let core_server_id = parse_args(args)?;
let processor = EventProcessor::new(core_server_id).chain_err(|| ErrorKind::InitHandleFailed)?;
unsafe {
(*retptr).type_mask = openvpn_ffi::events_to_bitmask(INTERESTING_EVENTS);
// Converting the handle into a raw pointer will make it escape Rust deallocation. See
// `openvpn_plugin_close_v1` for deallocation.
(*retptr).handle = Box::into_raw(Box::new(processor)) as *const c_void;
}
Ok(())
}
fn parse_args(args: *const openvpn_plugin_args_open_in) -> Result<talpid_ipc::IpcServerId> {
let mut args_iter = unsafe { openvpn_ffi::parse::string_array((*args).argv) }
.chain_err(|| ErrorKind::ParseArgsFailed)?
.into_iter();
let _plugin_path = args_iter.next();
let core_server_id: String = args_iter.next()
.ok_or_else(|| ErrorKind::Msg("No core server id given as first argument".to_owned()))?;
Ok(core_server_id)
}
/// Called by OpenVPN just before the plugin is unloaded. Should correctly close the plugin and
/// deallocate any `handle` initialized by the plugin in `openvpn_plugin_open_v3`
#[no_mangle]
pub extern "C" fn openvpn_plugin_close_v1(handle: *const c_void) {
debug!("Unloading plugin");
// IMPORTANT: Bring the handle object back from a raw pointer. This will cause the handle
// object to be properly deallocated right here.
let _ = unsafe { Box::from_raw(handle as *mut EventProcessor) };
}
/// Called by OpenVPN for each `OPENVPN_PLUGIN_*` event that it registered for in
/// `openvpn_plugin_open_v3`
#[no_mangle]
pub extern "C" fn openvpn_plugin_func_v3(_version: c_int,
args: *const openvpn_plugin_args_func_in,
_retptr: *const openvpn_plugin_args_func_return)
-> c_int {
match openvpn_plugin_func_v3_internal(args) {
Ok(_) => OPENVPN_PLUGIN_FUNC_SUCCESS,
Err(e) => {
log_error("Error while processing event", &e);
OPENVPN_PLUGIN_FUNC_ERROR
}
}
}
fn openvpn_plugin_func_v3_internal(args: *const openvpn_plugin_args_func_in) -> Result<()> {
let event_type = unsafe { (*args).event_type };
let event = OpenVpnPluginEvent::from_int(event_type).chain_err(|| ErrorKind::InvalidEventType)?;
debug!("Received event: {:?}", event);
let env = unsafe { openvpn_ffi::parse::env((*args).envp) }
.chain_err(|| ErrorKind::ParseEnvFailed)?;
let mut handle = unsafe { Box::from_raw((*args).handle as *mut EventProcessor) };
handle.process_event(event, env).chain_err(|| ErrorKind::EventProcessingFailed)?;
// Convert the handle back to a raw pointer to not deallocate it when we return.
Box::into_raw(handle);
Ok(())
}
pub fn init_logger() -> ::std::result::Result<(), ()> {
env_logger::init().or_else(
|e| {
use std::io::Write;
let mut stderr = ::std::io::stderr();
writeln!(&mut stderr, "Unable to initialize logging: {}", e)
.expect("Unable to write to stderr");
Err(())
},
)
}
pub fn log_error(msg: &str, error: &Error) {
error!("{}", msg);
for e in error.iter() {
error!("caused by: {}", e);
}
// When running with RUST_BACKTRACE=1, print backtrace.
if let Some(backtrace) = error.backtrace() {
error!("backtrace: {:?}", backtrace);
}
}
|
