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cliproto.hpp
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// OpenVPN -- An application to securely tunnel IP networks
// over a single port, with support for SSL/TLS-based
// session authentication and key exchange,
// packet encryption, packet authentication, and
// packet compression.
//
// Copyright (C) 2012- OpenVPN Inc.
//
// SPDX-License-Identifier: MPL-2.0 OR AGPL-3.0-only WITH openvpn3-openssl-exception
//
#ifndef OPENVPN_CLIENT_CLIPROTO_H
#define OPENVPN_CLIENT_CLIPROTO_H
// This is a middle-layer object in the OpenVPN client protocol stack.
// It is above the general OpenVPN protocol implementation in
// class ProtoContext but below the top
// level object in a client connect (ClientConnect). See ClientConnect for
// a fuller description of the full client stack.
//
// This layer deals with setting up an OpenVPN client connection:
//
// 1. handles creation of transport-layer handler via TransportClientFactory
// 2. handles creation of tun-layer handler via TunClientFactory
// 3. handles sending PUSH_REQUEST to server and processing reply of server-pushed options
// 4. manages the underlying OpenVPN protocol object (class ProtoContext)
// 5. handles timers on behalf of the underlying OpenVPN protocol object
// 6. acts as an exception dispatcher for errors occuring in any of the underlying layers
#include <string>
#include <vector>
#include <memory>
#include <algorithm> // for std::min
#include <cstdint> // for std::uint...
using namespace std::chrono_literals;
#include <openvpn/io/io.hpp>
#include <openvpn/common/rc.hpp>
#include <openvpn/common/count.hpp>
#include <openvpn/common/string.hpp>
#include <openvpn/common/base64.hpp>
#include <openvpn/common/clamp_typerange.hpp>
#include <openvpn/ip/ptb.hpp>
#include <openvpn/tun/client/tunbase.hpp>
#include <openvpn/transport/client/transbase.hpp>
#include <openvpn/transport/client/relay.hpp>
#include <openvpn/options/continuation.hpp>
#include <openvpn/options/sanitize.hpp>
#include <openvpn/client/acc_certcheck.hpp>
#include <openvpn/client/clievent.hpp>
#include <openvpn/client/clicreds.hpp>
#include <openvpn/client/cliconstants.hpp>
#include <openvpn/client/clihalt.hpp>
#include <openvpn/client/optfilt.hpp>
#include <openvpn/time/asiotimer.hpp>
#include <openvpn/time/coarsetime.hpp>
#include <openvpn/time/durhelper.hpp>
#include <openvpn/error/excode.hpp>
#include <openvpn/ssl/proto.hpp>
#include <openvpn/client/remotelist.hpp>
#ifdef OPENVPN_DEBUG_CLIPROTO
#define OPENVPN_LOG_CLIPROTO(x) OPENVPN_LOG(x)
#else
#define OPENVPN_LOG_CLIPROTO(x)
#endif
using openvpn::numeric_util::clamp_to_typerange;
namespace openvpn::ClientProto {
struct NotifyCallback
{
virtual ~NotifyCallback() = default;
virtual void client_proto_terminate() = 0;
virtual void client_proto_connected()
{
}
virtual void client_proto_auth_pending_timeout(int timeout)
{
}
virtual void client_proto_renegotiated()
{
}
};
class Session : ProtoContextCallbackInterface,
TransportClientParent,
TunClientParent,
public RC<thread_unsafe_refcount>
{
static inline const std::string certcheckProto = "cck1";
public:
typedef RCPtr<Session> Ptr;
OPENVPN_EXCEPTION(client_exception);
OPENVPN_EXCEPTION(client_halt_restart);
OPENVPN_EXCEPTION(tun_exception);
OPENVPN_EXCEPTION(transport_exception);
OPENVPN_EXCEPTION(max_pushed_options_exceeded);
OPENVPN_SIMPLE_EXCEPTION(session_invalidated);
OPENVPN_SIMPLE_EXCEPTION(authentication_failed);
OPENVPN_SIMPLE_EXCEPTION(inactive_timer_expired);
OPENVPN_SIMPLE_EXCEPTION(relay_event);
OPENVPN_EXCEPTION(proxy_exception);
struct Config : public RC<thread_unsafe_refcount>
{
typedef RCPtr<Config> Ptr;
Config()
: pushed_options_limit("server-pushed options data too large",
ProfileParseLimits::MAX_PUSH_SIZE,
ProfileParseLimits::OPT_OVERHEAD,
ProfileParseLimits::TERM_OVERHEAD,
0,
ProfileParseLimits::MAX_DIRECTIVE_SIZE)
{
}
ProtoContext::ProtoConfig::Ptr proto_context_config;
ProtoContextCompressionOptions::Ptr proto_context_options;
CryptoAlgs::Type cipher = CryptoAlgs::Type::NONE;
CryptoAlgs::Type cipher_override = CryptoAlgs::Type::NONE;
PushOptionsBase::Ptr push_base;
TransportClientFactory::Ptr transport_factory;
TunClientFactory::Ptr tun_factory;
SessionStats::Ptr cli_stats;
ClientEvent::Queue::Ptr cli_events;
ClientCreds::Ptr creds;
OptionList::Limits pushed_options_limit;
OptionList::FilterBase::Ptr pushed_options_filter;
unsigned int tcp_queue_limit = 64;
bool ncp_disable = false;
bool echo = false;
bool info = false;
bool autologin_sessions = false;
};
Session(openvpn_io::io_context &io_context_arg,
const Config &config,
NotifyCallback *notify_callback_arg)
: proto_context(this, config.proto_context_config, config.cli_stats),
io_context(io_context_arg),
transport_factory(config.transport_factory),
tun_factory(config.tun_factory),
tcp_queue_limit(config.tcp_queue_limit),
notify_callback(notify_callback_arg),
housekeeping_timer(io_context_arg),
push_request_timer(io_context_arg),
received_options(config.push_base),
creds(config.creds),
proto_context_options(config.proto_context_options),
cipher(config.cipher),
cipher_override(config.cipher_override),
cli_stats(config.cli_stats),
cli_events(config.cli_events),
echo(config.echo),
info(config.info),
pushed_options_limit(config.pushed_options_limit),
pushed_options_filter(config.pushed_options_filter),
inactive_timer(io_context_arg),
info_hold_timer(io_context_arg)
{
#ifdef OPENVPN_PACKET_LOG
packet_log.open(OPENVPN_PACKET_LOG, std::ios::binary);
if (!packet_log)
OPENVPN_THROW(open_file_error, "cannot open packet log for output: " << OPENVPN_PACKET_LOG);
#endif
proto_context.update_now();
proto_context.reset();
// proto_context.enable_strict_openvpn_2x();
info_hold.reset(new std::vector<ClientEvent::Base::Ptr>());
}
bool first_packet_received() const
{
return first_packet_received_;
}
void start()
{
if (!halt)
{
proto_context.update_now();
// coarse wakeup range
housekeeping_schedule.init(Time::Duration::binary_ms(512), Time::Duration::binary_ms(1024));
// initialize transport-layer packet handler
transport = transport_factory->new_transport_client_obj(io_context, this);
transport_has_send_queue = transport->transport_has_send_queue();
if (transport_factory->is_relay())
transport_connecting();
else
transport->transport_start();
}
}
TransportClientFactory::Ptr transport_factory_relay()
{
TransportClient::Ptr tc(new TransportRelayFactory::TransportClientNull(transport.get()));
tc.swap(transport);
return new TransportRelayFactory(io_context, std::move(tc), this);
}
void transport_factory_override(TransportClientFactory::Ptr factory)
{
transport_factory = std::move(factory);
}
void send_explicit_exit_notify()
{
if (!halt)
proto_context.send_explicit_exit_notify();
}
void tun_set_disconnect()
{
if (tun)
tun->set_disconnect();
}
/**
* Posts a control message from the client API. To ensure the client that will always send
* valid message (e.g. no extra newlines or invalid) character this method will first check the
* message for validity before sending it to the control channel
* @param msg control channel message
*/
void validate_and_post_cc_msg(const std::string &msg)
{
if (!Unicode::is_valid_utf8(msg, Unicode::UTF8_NO_CTRL))
{
ClientEvent::Base::Ptr ev = new ClientEvent::UnsupportedFeature{"Invalid chars in control message", "Control channel message with invalid characters not allowed to be send with post_cc_msg", false};
cli_events->add_event(std::move(ev));
return;
}
post_cc_msg(msg);
}
/**
* Post a control message to the control channel. This only intended to be used by consumers that
* either validated the message itself beforehand or construct a message in a way that it is
* always valid.
* @param msg The message to send on the control channel.
*/
void post_cc_msg(const std::string &msg)
{
proto_context.update_now();
proto_context.write_control_string(msg);
proto_context.flush(true);
set_housekeeping_timer();
}
void post_app_control_message(const std::string proto, const std::string message)
{
if (!proto_context.conf().app_control_config.supports_protocol(proto))
{
ClientEvent::Base::Ptr ev = new ClientEvent::UnsupportedFeature{"missing acc protocol support", "server has not announced support of this custom app control protocol", false};
cli_events->add_event(std::move(ev));
return;
}
for (auto fragment : proto_context.conf().app_control_config.format_message(proto, message))
post_cc_msg(std::move(fragment));
}
void stop(const bool call_terminate_callback)
{
if (!halt)
{
halt = true;
housekeeping_timer.cancel();
push_request_timer.cancel();
out_tun_callback_.reset();
in_tun_callback_.reset();
inactive_timer.cancel();
info_hold_timer.cancel();
if (notify_callback && call_terminate_callback)
notify_callback->client_proto_terminate();
if (tun)
tun->stop(); // call after client_proto_terminate() so it can call back to tun_set_disconnect
if (transport)
transport->stop();
}
}
void stop_on_signal(const openvpn_io::error_code& error, int signal_number)
{
stop(true);
}
bool reached_connected_state() const
{
return bool(connected_);
}
// If fatal() returns something other than Error::UNDEF, it
// is intended to flag the higher levels (cliconnect.hpp)
// that special handling is required. This handling might include
// considering the error to be fatal and stopping future connect
// retries, or emitting a special event. See cliconnect.hpp
// for actual implementation.
Error::Type fatal() const
{
return fatal_;
}
const std::string &fatal_reason() const
{
return fatal_reason_;
}
// Getters for values which could potentially be modified by
// a server's AUTH_FAILED,TEMP response flags
RemoteList::Advance advance_type() const
{
return temp_fail_advance_;
}
std::chrono::milliseconds reconnect_delay() const
{
return temp_fail_backoff_;
}
/**
@brief Start up the cert check handshake using the given certs and key
@param config SSL Config setup with the correct keys and certificates
Begins the handshake with Client Hello via the ACC.
*/
void start_acc_certcheck(SSLLib::SSLAPI::Config::Ptr config)
{
certcheck_hs.reset(std::move(config));
do_acc_certcheck(std::string(""));
}
virtual ~Session()
{
stop(false);
}
private:
bool transport_is_openvpn_protocol() override
{
return true;
}
// transport obj calls here with incoming packets
void transport_recv(BufferAllocated& buf) override
{
try
{
OPENVPN_LOG_CLIPROTO("Transport RECV " << server_endpoint_render() << ' ' << proto_context.dump_packet(buf));
// update current time
proto_context.update_now();
// update last packet received
proto_context.stat().update_last_packet_received(proto_context.now());
// log connecting event (only on first packet received)
if (!first_packet_received_)
{
ClientEvent::Base::Ptr ev = new ClientEvent::Connecting();
cli_events->add_event(std::move(ev));
first_packet_received_ = true;
}
// get packet type
ProtoContext::PacketType pt = proto_context.packet_type(buf);
// process packet
if (pt.is_data())
{
// data packet
proto_context.data_decrypt(pt, buf);
if (buf.size())
{
#ifdef OPENVPN_PACKET_LOG
log_packet(buf, false);
#endif
// make packet appear as incoming on tun interface
if (tun)
{
OPENVPN_LOG_CLIPROTO("TUN send, size=" << buf.size());
tun->tun_send(buf);
}
}
// do a lightweight flush
proto_context.flush(false);
}
else if (pt.is_control())
{
// control packet
proto_context.control_net_recv(pt, std::move(buf));
// do a full flush
proto_context.flush(true);
}
else
cli_stats->error(Error::KEY_STATE_ERROR);
// schedule housekeeping wakeup
set_housekeeping_timer();
}
catch (const ExceptionCode& e)
{
if (e.code_defined())
{
if (e.fatal())
transport_error((Error::Type)e.code(), e.what());
else
cli_stats->error((Error::Type)e.code());
}
else
process_exception(e, "transport_recv_excode");
}
catch (const std::exception& e)
{
process_exception(e, "transport_recv");
}
}
void transport_needs_send() override
{
}
// tun i/o driver calls here with incoming packets
void tun_recv(BufferAllocated& buf) override
{
try
{
OPENVPN_LOG_CLIPROTO("TUN recv, size=" << buf.size());
// update current time
proto_context.update_now();
// log packet
#ifdef OPENVPN_PACKET_LOG
log_packet(buf, true);
#endif
// if transport layer has an output queue, check if it's full
if (transport_has_send_queue)
{
if (transport->transport_send_queue_size() > tcp_queue_limit)
{
buf.reset_size(); // queue full, drop packet
cli_stats->error(Error::TCP_OVERFLOW);
}
}
// encrypt packet
if (buf.size())
{
const ProtoContext::ProtoConfig &c = proto_context.conf();
bool df = true;
if (IPCommon::version(buf[0]) == IPCommon::IPv4 && buf.size() >= sizeof(struct IPv4Header))
{
df = IPv4Header::is_df_set(buf.c_data());
}
// when calculating mss, we take IPv4 and TCP headers into account
// here we need to add it back since we check the whole IP packet size, not just TCP payload
constexpr size_t MinTcpHeader = 20;
constexpr size_t MinIpHeader = 20;
size_t mss_no_tcp_ip_encap = c.mss_fix + (MinTcpHeader + MinIpHeader);
if (df && c.mss_fix > 0 && buf.size() > mss_no_tcp_ip_encap)
{
Ptb::generate_icmp_ptb(buf, clamp_to_typerange<unsigned short>(mss_no_tcp_ip_encap));
tun->tun_send(buf);
}
else
{
proto_context.data_encrypt(buf);
if (buf.size())
{
// send packet via transport to destination
OPENVPN_LOG_CLIPROTO("Transport SEND " << server_endpoint_render() << ' ' << proto_context.dump_packet(buf));
if (transport->transport_send(buf))
proto_context.update_last_sent();
else if (halt)
return;
}
}
}
// do a lightweight flush
proto_context.flush(false);
// schedule housekeeping wakeup
set_housekeeping_timer();
}
catch (const std::exception& e)
{
process_exception(e, "tun_recv");
}
}
// Return true if keepalive parameter(s) are enabled.
bool is_keepalive_enabled() const override
{
return proto_context.is_keepalive_enabled();
}
// Disable keepalive for rest of session, but fetch
// the keepalive parameters (in seconds).
void disable_keepalive(unsigned int &keepalive_ping,
unsigned int &keepalive_timeout) override
{
proto_context.disable_keepalive(keepalive_ping, keepalive_timeout);
}
void transport_pre_resolve() override
{
ClientEvent::Base::Ptr ev = new ClientEvent::Resolve();
cli_events->add_event(std::move(ev));
}
std::string server_endpoint_render()
{
std::string server_host, server_port, server_proto, server_ip;
transport->server_endpoint_info(server_host, server_port, server_proto, server_ip);
std::ostringstream out;
out << '[' << server_host << "]:" << server_port << " (" << server_ip << ") via " << server_proto;
return out.str();
}
void transport_wait_proxy() override
{
ClientEvent::Base::Ptr ev = new ClientEvent::WaitProxy();
cli_events->add_event(std::move(ev));
}
void transport_wait() override
{
ClientEvent::Base::Ptr ev = new ClientEvent::Wait();
cli_events->add_event(std::move(ev));
}
void transport_connecting() override
{
try
{
proto_context.conf().build_connect_time_peer_info_string(transport);
OPENVPN_LOG("Connecting to " << server_endpoint_render());
proto_context.set_protocol(transport->transport_protocol());
proto_context.set_cipher(cipher);
proto_context.set_cipher_override(cipher_override);
proto_context.set_ncp_disable(ncp_disable);
proto_context.start();
proto_context.flush(true);
set_housekeeping_timer();
}
catch (const std::exception &e)
{
process_exception(e, "transport_connecting");
}
}
void transport_error(const Error::Type fatal_err, const std::string& err_text) override
{
if (fatal_err != Error::UNDEF)
{
fatal_ = fatal_err;
fatal_reason_ = err_text;
}
if (notify_callback)
{
OPENVPN_LOG("Transport Error: " << err_text);
stop(true);
}
else
throw transport_exception(err_text);
}
void proxy_error(const Error::Type fatal_err, const std::string& err_text) override
{
if (fatal_err != Error::UNDEF)
{
fatal_ = fatal_err;
fatal_reason_ = err_text;
}
if (notify_callback)
{
OPENVPN_LOG("Proxy Error: " << err_text);
stop(true);
}
else
throw proxy_exception(err_text);
}
void extract_auth_token(const OptionList& opt)
{
std::string username;
// auth-token-user
{
const Option* o = opt.get_ptr("auth-token-user");
if (o)
username = base64->decode(o->get(1, 340)); // 255 chars after base64 decode
}
// auth-token
{
// if auth-token is present, use it as the password for future renegotiations
const Option* o = opt.get_ptr("auth-token");
if (o)
{
const std::string& sess_id = o->get(1, 256);
if (creds)
{
if (!username.empty())
OPENVPN_LOG("Session user: " << username);
#ifdef OPENVPN_SHOW_SESSION_TOKEN
OPENVPN_LOG("Session token: " << sess_id);
#else
OPENVPN_LOG("Session token: [redacted]");
#endif
proto_context.conf().set_xmit_creds(true);
creds->set_session_id(username, sess_id);
}
}
}
}
/**
* Parses a AUTH_FAILED,TEMP string, extracts the flags and returns
* the human readable reason part of it, if there is one. The string
* passed has the format "[flag(s)]:reason".
*
* Flags are optional and delimited by a comma (","). They are given
* as "key=value" strings. Currently there's support for parsing two keys:
* - backoff: seconds to wait between reconnects
* - advance: how to advance through the remote addresses list.
* Possible values are:
* - no: do not advance
* - addr: use the next address in the list (default)
* - remote: use the next remote's first address
*
* The reason string is free text and returned verbatim.
*
* @param msg The string to be parsed
*
* @return Returns the human readable reason for the auth failure or an
* empty string if not applicable.
*/
std::string parse_auth_failed_temp(const std::string& msg)
{
if (msg.empty())
return msg;
// Reset to default values
temp_fail_backoff_ = 0ms;
temp_fail_advance_ = RemoteList::Advance::Addr;
std::string::size_type reason_idx = 0;
auto endofflags = msg.find(']');
if (msg.at(0) == '[' && endofflags != std::string::npos)
{
reason_idx = ++endofflags;
auto flags = string::split(std::string{msg, 1, endofflags - 2}, ',');
for (const auto &flag : flags)
{
std::string key;
std::string value;
std::istringstream f(flag);
f >> key >> value;
if (f.fail())
{
OPENVPN_LOG("invalid AUTH_FAILED,TEMP flag: " << flag);
continue;
}
if (key == "backoff")
{
int timeout;
if (!parse_number(value, timeout))
{
OPENVPN_LOG("invalid AUTH_FAILED,TEMP flag: " << flag);
}
temp_fail_backoff_ = std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::seconds{timeout});
}
else if (key == "advance")
{
if (value == "no")
{
temp_fail_advance_ = RemoteList::Advance::None;
}
else if (value == "addr")
{
temp_fail_advance_ = RemoteList::Advance::Addr;
}
else if (value == "remote")
{
temp_fail_advance_ = RemoteList::Advance::Remote;
}
else
{
OPENVPN_LOG("unknown AUTH_FAILED,TEMP flag: " << flag);
}
}
else
{
OPENVPN_LOG("unknown AUTH_FAILED,TEMP flag: " << flag);
}
}
}
if (reason_idx >= msg.size() || msg[reason_idx] != ':')
return "";
// skip leading colon
return msg.substr(reason_idx + 1);
}
// proto base class calls here for control channel network sends
void control_net_send(const Buffer &net_buf) override
{
OPENVPN_LOG_CLIPROTO("Transport SEND " << server_endpoint_render() << ' ' << proto_context.dump_packet(net_buf));
if (transport->transport_send_const(net_buf))
proto_context.update_last_sent();
}
void recv_auth_failed(const std::string &msg)
{
std::string reason;
std::string log_reason;
// get reason (if it exists) for authentication failure
if (msg.length() >= 13)
reason = string::trim_left_copy(std::string(msg, 12));
if (string::starts_with(reason, "TEMP"))
{
log_reason = "AUTH_FAILED_TEMP:" + parse_auth_failed_temp(std::string(reason, 4));
}
else
{
bool password_defined = false;
bool session_id_defined = false;
if (creds)
{
password_defined = creds->password_defined();
session_id_defined = creds->session_id_defined();
// authentication failure, purge auth-token
creds->purge_session_id();
}
// do we have a session-id?
if (session_id_defined)
{
bool reconnect = false;
// if there was an OOB auth (server pushed AUTH_PENDING) throw a fatal error since we need a user input
if (!creds->need_user_interaction())
{
// reconnect if we have a password OR password is not needed
if (!creds->password_needed() || password_defined)
{
reconnect = true;
}
}
OPENVPN_LOG("need_user_interaction: " << creds->need_user_interaction() << ", pw_needed: " << creds->password_needed() << ", pw_defined: " << password_defined << ", reconnect: " << reconnect);
if (reconnect)
{
log_reason = "SESSION_AUTH_FAILED";
}
else
{
// we don't have a password and we need a user input, throw a fatal error and let the client to re-authenticate
fatal_ = Error::SESSION_EXPIRED;
fatal_reason_ = reason;
log_reason = "SESSION_EXPIRED";
}
}
else
{
// no session-id, throw fatal error
fatal_ = Error::AUTH_FAILED;
fatal_reason_ = reason;
log_reason = "AUTH_FAILED";
}
}
if (notify_callback)
{
OPENVPN_LOG(log_reason);
stop(true);
}
else
throw authentication_failed();
}
void recv_auth_pending(const std::string &msg)
{
// AUTH_PENDING indicates an out-of-band authentication step must
// be performed before the server will send the PUSH_REPLY message.
if (!auth_pending)
{
auth_pending = true;
std::string key_words;
unsigned int timeout = 0;
if (string::starts_with(msg, "AUTH_PENDING,"))
{
key_words = msg.substr(strlen("AUTH_PENDING,"));
auto opts = OptionList::parse_from_csv_static(key_words, nullptr);
std::string timeout_str = opts.get_optional("timeout", 1, 20);
if (timeout_str != "")
{
try
{
timeout = clamp_to_typerange<unsigned int>(std::stoul(timeout_str));
// Cap the timeout to end well before renegotiation starts
timeout = std::min(timeout, static_cast<decltype(timeout)>(proto_context.conf().renegotiate.to_seconds() / 2));
}
catch (const std::logic_error &)
{
OPENVPN_LOG("could not parse AUTH_PENDING timeout: " << timeout_str);
}
}
}
if (notify_callback && timeout > 0)
{
notify_callback->client_proto_auth_pending_timeout(timeout);
}
ClientEvent::Base::Ptr ev = new ClientEvent::AuthPending(timeout, std::move(key_words));
cli_events->add_event(std::move(ev));
}
}
void recv_relay()
{
if (proto_context.conf().relay_mode)
{
fatal_ = Error::RELAY;
fatal_reason_ = "";
}
else
{
fatal_ = Error::RELAY_ERROR;
fatal_reason_ = "not in relay mode";
}
if (notify_callback)
{
OPENVPN_LOG(Error::name(fatal_) << ' ' << fatal_reason_);
stop(true);
}
else
throw relay_event();
}
void recv_info(const std::string &msg, bool info_pre)
{
// Buffer INFO messages received near Connected event to fire
// one second after Connected event, to reduce the chance of
// race conditions in the client app, if the INFO event
// triggers the client app to perform an operation that
// requires the VPN tunnel to be ready.
std::string info_msg;
if (info_pre)
info_msg = msg.substr(std::string_view{"INFO_PRE,"}.length());
else
info_msg = msg.substr(std::string_view{"INFO,"}.length());
if (string::starts_with(info_msg, "ACC:"))
{
// We want this to be parsed exactly like the custom-control option.
// That means we replace ACC: with custom-control for the parser.
auto acc_options = OptionList::parse_from_csv_static("custom-control " + info_msg.substr(std::strlen("ACC:")), &pushed_options_limit);
proto_context.conf().parse_custom_app_control(acc_options);
// check if we need to notify about ACC protocols
notify_client_acc_protocols();
}
else
{
if ((string::starts_with(info_msg, "WEB_AUTH:") || string::starts_with(info_msg, "CR_TEXT:")) && creds)
{
creds->set_need_user_interaction();
}
ClientEvent::Info::Ptr ev = new ClientEvent::Info(std::move(info_msg));
// INFO_PRE is like INFO but it is never buffered
if (info_hold && !info_pre)
info_hold->push_back(std::move(ev));
else
cli_events->add_event(std::move(ev));
}
}
/**
* @brief Handles incoming PUSH_UPDATE message
*
* @param msg Comma-separated list of options prefixed with PUSH_UPDATE tag
*/
void recv_push_update(const std::string &msg)
{
received_options.reset_completion();
// parse the received options
auto opt_str = msg.substr(strlen("PUSH_UPDATE,"));
auto opts = OptionList::parse_from_csv_static(opt_str, &pushed_options_limit);
received_options.add(opts, pushed_options_filter.get(), true);
if (received_options.complete())
{
// show options
OPENVPN_LOG("PUSH UPDATE:\n"
<< render_options_sanitized(opts, Option::RENDER_PASS_FMT | Option::RENDER_NUMBER | Option::RENDER_BRACKET));
// Merge local and pushed options
received_options.finalize(pushed_options_merger);
if (tun)
{
tun->apply_push_update(received_options, *transport);
}
}
}
// proto base class calls here for app-level control-channel messages received
void control_recv(BufferPtr &&app_bp) override
{
const std::string msg = ProtoContext::read_control_string<std::string>(*app_bp);
if (!Unicode::is_valid_utf8(msg, Unicode::UTF8_NO_CTRL))
{
OPENVPN_LOG("Control channel message with invalid characters received, ignoring message");
return;
}
//OPENVPN_LOG("SERVER: " << sanitize_control_message(msg));
if (string::starts_with(msg, "PUSH_REPLY,"))
{
recv_push_reply(msg);
}
else if (string::starts_with(msg, "AUTH_FAILED"))
{
recv_auth_failed(msg);
}
else if (ClientHalt::match(msg))
{
recv_halt_restart(msg);
}
else if (info && string::starts_with(msg, "INFO,"))
{
recv_info(msg, false);
}
else if (info && string::starts_with(msg, "INFO_PRE,"))
{
recv_info(msg, true);
}
else if (msg == "AUTH_PENDING" || string::starts_with(msg, "AUTH_PENDING,"))
{
recv_auth_pending(msg);
}
else if (msg == "RELAY")
{
recv_relay();
}
else if (string::starts_with(msg, "ACC,"))
{
recv_custom_control_message(msg);
}
else if (string::starts_with(msg, "PUSH_UPDATE,"))
{
recv_push_update(msg);
}
}
/**
@brief receive, validate, and dispatch ACC messages
@param msg the received message
This function's main purpose is to receive a custom control message from the server, parse
out the protocol and contents, validate the protocol is supported, and queue a ClientEvent
for supported protocols to be handled later. It acts as the interface between the lower-level