godot/modules/mbedtls/packet_peer_mbed_dtls.cpp
Rémi Verschelde 1426cd3b3a
One Copyright Update to rule them all
As many open source projects have started doing it, we're removing the
current year from the copyright notice, so that we don't need to bump
it every year.

It seems like only the first year of publication is technically
relevant for copyright notices, and even that seems to be something
that many companies stopped listing altogether (in a version controlled
codebase, the commits are a much better source of date of publication
than a hardcoded copyright statement).

We also now list Godot Engine contributors first as we're collectively
the current maintainers of the project, and we clarify that the
"exclusive" copyright of the co-founders covers the timespan before
opensourcing (their further contributions are included as part of Godot
Engine contributors).

Also fixed "cf." Frenchism - it's meant as "refer to / see".

Backported from #70885.
2023-01-10 15:26:54 +01:00

289 lines
9.0 KiB
C++

/**************************************************************************/
/* packet_peer_mbed_dtls.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#include "packet_peer_mbed_dtls.h"
#include "mbedtls/platform_util.h"
#include "core/io/stream_peer_ssl.h"
#include "core/os/file_access.h"
int PacketPeerMbedDTLS::bio_send(void *ctx, const unsigned char *buf, size_t len) {
if (buf == nullptr || len <= 0) {
return 0;
}
PacketPeerMbedDTLS *sp = (PacketPeerMbedDTLS *)ctx;
ERR_FAIL_COND_V(sp == nullptr, 0);
Error err = sp->base->put_packet((const uint8_t *)buf, len);
if (err == ERR_BUSY) {
return MBEDTLS_ERR_SSL_WANT_WRITE;
} else if (err != OK) {
ERR_FAIL_V(MBEDTLS_ERR_SSL_INTERNAL_ERROR);
}
return len;
}
int PacketPeerMbedDTLS::bio_recv(void *ctx, unsigned char *buf, size_t len) {
if (buf == nullptr || len <= 0) {
return 0;
}
PacketPeerMbedDTLS *sp = (PacketPeerMbedDTLS *)ctx;
ERR_FAIL_COND_V(sp == nullptr, 0);
int pc = sp->base->get_available_packet_count();
if (pc == 0) {
return MBEDTLS_ERR_SSL_WANT_READ;
} else if (pc < 0) {
ERR_FAIL_V(MBEDTLS_ERR_SSL_INTERNAL_ERROR);
}
const uint8_t *buffer;
int buffer_size = 0;
Error err = sp->base->get_packet(&buffer, buffer_size);
if (err != OK) {
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
memcpy(buf, buffer, buffer_size);
return buffer_size;
}
void PacketPeerMbedDTLS::_cleanup() {
ssl_ctx->clear();
base = Ref<PacketPeer>();
status = STATUS_DISCONNECTED;
}
int PacketPeerMbedDTLS::_set_cookie() {
// Setup DTLS session cookie for this client
uint8_t client_id[18];
IP_Address addr = base->get_packet_address();
uint16_t port = base->get_packet_port();
memcpy(client_id, addr.get_ipv6(), 16);
memcpy(&client_id[16], (uint8_t *)&port, 2);
return mbedtls_ssl_set_client_transport_id(ssl_ctx->get_context(), client_id, 18);
}
Error PacketPeerMbedDTLS::_do_handshake() {
int ret = 0;
while ((ret = mbedtls_ssl_handshake(ssl_ctx->get_context())) != 0) {
if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
if (ret != MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED) {
ERR_PRINT("TLS handshake error: " + itos(ret));
SSLContextMbedTLS::print_mbedtls_error(ret);
}
_cleanup();
status = STATUS_ERROR;
return FAILED;
}
// Will retry via poll later
return OK;
}
status = STATUS_CONNECTED;
return OK;
}
Error PacketPeerMbedDTLS::connect_to_peer(Ref<PacketPeerUDP> p_base, bool p_validate_certs, const String &p_for_hostname, Ref<X509Certificate> p_ca_certs) {
ERR_FAIL_COND_V(!p_base.is_valid() || !p_base->is_connected_to_host(), ERR_INVALID_PARAMETER);
base = p_base;
int ret = 0;
int authmode = p_validate_certs ? MBEDTLS_SSL_VERIFY_REQUIRED : MBEDTLS_SSL_VERIFY_NONE;
Error err = ssl_ctx->init_client(MBEDTLS_SSL_TRANSPORT_DATAGRAM, authmode, p_ca_certs);
ERR_FAIL_COND_V(err != OK, err);
mbedtls_ssl_set_hostname(ssl_ctx->get_context(), p_for_hostname.utf8().get_data());
mbedtls_ssl_set_bio(ssl_ctx->get_context(), this, bio_send, bio_recv, nullptr);
mbedtls_ssl_set_timer_cb(ssl_ctx->get_context(), &timer, mbedtls_timing_set_delay, mbedtls_timing_get_delay);
status = STATUS_HANDSHAKING;
if ((ret = _do_handshake()) != OK) {
status = STATUS_ERROR_HOSTNAME_MISMATCH;
return FAILED;
}
return OK;
}
Error PacketPeerMbedDTLS::accept_peer(Ref<PacketPeerUDP> p_base, Ref<CryptoKey> p_key, Ref<X509Certificate> p_cert, Ref<X509Certificate> p_ca_chain, Ref<CookieContextMbedTLS> p_cookies) {
Error err = ssl_ctx->init_server(MBEDTLS_SSL_TRANSPORT_DATAGRAM, MBEDTLS_SSL_VERIFY_NONE, p_key, p_cert, p_cookies);
ERR_FAIL_COND_V(err != OK, err);
base = p_base;
base->set_blocking_mode(false);
mbedtls_ssl_session_reset(ssl_ctx->get_context());
int ret = _set_cookie();
if (ret != 0) {
_cleanup();
ERR_FAIL_V_MSG(FAILED, "Error setting DTLS client cookie");
}
mbedtls_ssl_set_bio(ssl_ctx->get_context(), this, bio_send, bio_recv, nullptr);
mbedtls_ssl_set_timer_cb(ssl_ctx->get_context(), &timer, mbedtls_timing_set_delay, mbedtls_timing_get_delay);
status = STATUS_HANDSHAKING;
if ((ret = _do_handshake()) != OK) {
status = STATUS_ERROR;
return FAILED;
}
return OK;
}
Error PacketPeerMbedDTLS::put_packet(const uint8_t *p_buffer, int p_bytes) {
ERR_FAIL_COND_V(status != STATUS_CONNECTED, ERR_UNCONFIGURED);
if (p_bytes == 0) {
return OK;
}
int ret = mbedtls_ssl_write(ssl_ctx->get_context(), p_buffer, p_bytes);
if (ret == MBEDTLS_ERR_SSL_WANT_READ || ret == MBEDTLS_ERR_SSL_WANT_WRITE) {
ret = 0; // non blocking io
} else if (ret <= 0) {
SSLContextMbedTLS::print_mbedtls_error(ret);
_cleanup();
return ERR_CONNECTION_ERROR;
}
return OK;
}
Error PacketPeerMbedDTLS::get_packet(const uint8_t **r_buffer, int &r_bytes) {
ERR_FAIL_COND_V(status != STATUS_CONNECTED, ERR_UNCONFIGURED);
r_bytes = 0;
int ret = mbedtls_ssl_read(ssl_ctx->get_context(), packet_buffer, PACKET_BUFFER_SIZE);
if (ret == MBEDTLS_ERR_SSL_WANT_READ || ret == MBEDTLS_ERR_SSL_WANT_WRITE) {
ret = 0; // non blocking io
} else if (ret <= 0) {
if (ret == MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY) {
// Also send close notify back
disconnect_from_peer();
} else {
_cleanup();
status = STATUS_ERROR;
SSLContextMbedTLS::print_mbedtls_error(ret);
}
return ERR_CONNECTION_ERROR;
}
*r_buffer = packet_buffer;
r_bytes = ret;
return OK;
}
void PacketPeerMbedDTLS::poll() {
if (status == STATUS_HANDSHAKING) {
_do_handshake();
return;
} else if (status != STATUS_CONNECTED) {
return;
}
ERR_FAIL_COND(!base.is_valid());
int ret = mbedtls_ssl_read(ssl_ctx->get_context(), nullptr, 0);
if (ret < 0 && ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
if (ret == MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY) {
// Also send close notify back
disconnect_from_peer();
} else {
_cleanup();
status = STATUS_ERROR;
SSLContextMbedTLS::print_mbedtls_error(ret);
}
}
}
int PacketPeerMbedDTLS::get_available_packet_count() const {
ERR_FAIL_COND_V(status != STATUS_CONNECTED, 0);
return mbedtls_ssl_get_bytes_avail(&(ssl_ctx->ssl)) > 0 ? 1 : 0;
}
int PacketPeerMbedDTLS::get_max_packet_size() const {
return 488; // 512 (UDP in Godot) - 24 (DTLS header)
}
PacketPeerMbedDTLS::PacketPeerMbedDTLS() {
ssl_ctx.instance();
status = STATUS_DISCONNECTED;
}
PacketPeerMbedDTLS::~PacketPeerMbedDTLS() {
disconnect_from_peer();
}
void PacketPeerMbedDTLS::disconnect_from_peer() {
if (status != STATUS_CONNECTED && status != STATUS_HANDSHAKING) {
return;
}
if (status == STATUS_CONNECTED) {
int ret = 0;
// Send SSL close notification, blocking, but ignore other errors.
do {
ret = mbedtls_ssl_close_notify(ssl_ctx->get_context());
} while (ret == MBEDTLS_ERR_SSL_WANT_WRITE);
}
_cleanup();
}
PacketPeerMbedDTLS::Status PacketPeerMbedDTLS::get_status() const {
return status;
}
PacketPeerDTLS *PacketPeerMbedDTLS::_create_func() {
return memnew(PacketPeerMbedDTLS);
}
void PacketPeerMbedDTLS::initialize_dtls() {
_create = _create_func;
available = true;
}
void PacketPeerMbedDTLS::finalize_dtls() {
_create = nullptr;
available = false;
}