quic_port.c
/*
* Copyright 2023-2024 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include "internal/quic_port.h"
#include "internal/quic_channel.h"
#include "internal/quic_lcidm.h"
#include "internal/quic_srtm.h"
#include "quic_port_local.h"
#include "quic_channel_local.h"
#include "quic_engine_local.h"
#include "../ssl_local.h"
/*
* QUIC Port Structure
* ===================
*/
#define INIT_DCID_LEN 8
static int port_init(QUIC_PORT *port);
static void port_cleanup(QUIC_PORT *port);
static OSSL_TIME get_time(void *arg);
static void port_default_packet_handler(QUIC_URXE *e, void *arg,
const QUIC_CONN_ID *dcid);
static void port_rx_pre(QUIC_PORT *port);
DEFINE_LIST_OF_IMPL(ch, QUIC_CHANNEL);
DEFINE_LIST_OF_IMPL(port, QUIC_PORT);
QUIC_PORT *ossl_quic_port_new(const QUIC_PORT_ARGS *args)
{
QUIC_PORT *port;
if ((port = OPENSSL_zalloc(sizeof(QUIC_PORT))) == NULL)
return NULL;
port->engine = args->engine;
port->channel_ctx = args->channel_ctx;
port->is_multi_conn = args->is_multi_conn;
if (!port_init(port)) {
OPENSSL_free(port);
return NULL;
}
return port;
}
void ossl_quic_port_free(QUIC_PORT *port)
{
if (port == NULL)
return;
port_cleanup(port);
OPENSSL_free(port);
}
static int port_init(QUIC_PORT *port)
{
size_t rx_short_dcid_len = (port->is_multi_conn ? INIT_DCID_LEN : 0);
if (port->engine == NULL || port->channel_ctx == NULL)
goto err;
if ((port->err_state = OSSL_ERR_STATE_new()) == NULL)
goto err;
if ((port->demux = ossl_quic_demux_new(/*BIO=*/NULL,
/*Short CID Len=*/rx_short_dcid_len,
get_time, port)) == NULL)
goto err;
ossl_quic_demux_set_default_handler(port->demux,
port_default_packet_handler,
port);
if ((port->srtm = ossl_quic_srtm_new(port->engine->libctx,
port->engine->propq)) == NULL)
goto err;
if ((port->lcidm = ossl_quic_lcidm_new(port->engine->libctx,
rx_short_dcid_len)) == NULL)
goto err;
port->rx_short_dcid_len = (unsigned char)rx_short_dcid_len;
port->tx_init_dcid_len = INIT_DCID_LEN;
port->state = QUIC_PORT_STATE_RUNNING;
ossl_list_port_insert_tail(&port->engine->port_list, port);
port->on_engine_list = 1;
return 1;
err:
port_cleanup(port);
return 0;
}
static void port_cleanup(QUIC_PORT *port)
{
assert(ossl_list_ch_num(&port->channel_list) == 0);
ossl_quic_demux_free(port->demux);
port->demux = NULL;
ossl_quic_srtm_free(port->srtm);
port->srtm = NULL;
ossl_quic_lcidm_free(port->lcidm);
port->lcidm = NULL;
OSSL_ERR_STATE_free(port->err_state);
port->err_state = NULL;
if (port->on_engine_list) {
ossl_list_port_remove(&port->engine->port_list, port);
port->on_engine_list = 0;
}
}
static void port_transition_failed(QUIC_PORT *port)
{
if (port->state == QUIC_PORT_STATE_FAILED)
return;
port->state = QUIC_PORT_STATE_FAILED;
}
int ossl_quic_port_is_running(const QUIC_PORT *port)
{
return port->state == QUIC_PORT_STATE_RUNNING;
}
QUIC_ENGINE *ossl_quic_port_get0_engine(QUIC_PORT *port)
{
return port->engine;
}
QUIC_REACTOR *ossl_quic_port_get0_reactor(QUIC_PORT *port)
{
return ossl_quic_engine_get0_reactor(port->engine);
}
QUIC_DEMUX *ossl_quic_port_get0_demux(QUIC_PORT *port)
{
return port->demux;
}
CRYPTO_MUTEX *ossl_quic_port_get0_mutex(QUIC_PORT *port)
{
return ossl_quic_engine_get0_mutex(port->engine);
}
OSSL_TIME ossl_quic_port_get_time(QUIC_PORT *port)
{
return ossl_quic_engine_get_time(port->engine);
}
static OSSL_TIME get_time(void *port)
{
return ossl_quic_port_get_time((QUIC_PORT *)port);
}
int ossl_quic_port_get_rx_short_dcid_len(const QUIC_PORT *port)
{
return port->rx_short_dcid_len;
}
int ossl_quic_port_get_tx_init_dcid_len(const QUIC_PORT *port)
{
return port->tx_init_dcid_len;
}
/*
* QUIC Port: Network BIO Configuration
* ====================================
*/
/* Determines whether we can support a given poll descriptor. */
static int validate_poll_descriptor(const BIO_POLL_DESCRIPTOR *d)
{
if (d->type == BIO_POLL_DESCRIPTOR_TYPE_SOCK_FD && d->value.fd < 0) {
ERR_raise(ERR_LIB_SSL, ERR_R_PASSED_INVALID_ARGUMENT);
return 0;
}
return 1;
}
BIO *ossl_quic_port_get_net_rbio(QUIC_PORT *port)
{
return port->net_rbio;
}
BIO *ossl_quic_port_get_net_wbio(QUIC_PORT *port)
{
return port->net_wbio;
}
static int port_update_poll_desc(QUIC_PORT *port, BIO *net_bio, int for_write)
{
BIO_POLL_DESCRIPTOR d = {0};
if (net_bio == NULL
|| (!for_write && !BIO_get_rpoll_descriptor(net_bio, &d))
|| (for_write && !BIO_get_wpoll_descriptor(net_bio, &d)))
/* Non-pollable BIO */
d.type = BIO_POLL_DESCRIPTOR_TYPE_NONE;
if (!validate_poll_descriptor(&d))
return 0;
/*
* TODO(QUIC MULTIPORT): We currently only support one port per
* engine/domain. This is necessitated because QUIC_REACTOR only supports a
* single pollable currently. In the future, once complete polling
* infrastructure has been implemented, this limitation can be removed.
*
* For now, just update the descriptor on the engine's reactor as we are
* guaranteed to be the only port under it.
*/
if (for_write)
ossl_quic_reactor_set_poll_w(&port->engine->rtor, &d);
else
ossl_quic_reactor_set_poll_r(&port->engine->rtor, &d);
return 1;
}
int ossl_quic_port_update_poll_descriptors(QUIC_PORT *port)
{
int ok = 1;
if (!port_update_poll_desc(port, port->net_rbio, /*for_write=*/0))
ok = 0;
if (!port_update_poll_desc(port, port->net_wbio, /*for_write=*/1))
ok = 0;
return ok;
}
/*
* QUIC_PORT does not ref any BIO it is provided with, nor is any ref
* transferred to it. The caller (e.g., QUIC_CONNECTION) is responsible for
* ensuring the BIO lasts until the channel is freed or the BIO is switched out
* for another BIO by a subsequent successful call to this function.
*/
int ossl_quic_port_set_net_rbio(QUIC_PORT *port, BIO *net_rbio)
{
if (port->net_rbio == net_rbio)
return 1;
if (!port_update_poll_desc(port, net_rbio, /*for_write=*/0))
return 0;
ossl_quic_demux_set_bio(port->demux, net_rbio);
port->net_rbio = net_rbio;
return 1;
}
int ossl_quic_port_set_net_wbio(QUIC_PORT *port, BIO *net_wbio)
{
QUIC_CHANNEL *ch;
if (port->net_wbio == net_wbio)
return 1;
if (!port_update_poll_desc(port, net_wbio, /*for_write=*/1))
return 0;
LIST_FOREACH(ch, ch, &port->channel_list)
ossl_qtx_set_bio(ch->qtx, net_wbio);
port->net_wbio = net_wbio;
return 1;
}
/*
* QUIC Port: Channel Lifecycle
* ============================
*/
static SSL *port_new_handshake_layer(QUIC_PORT *port)
{
SSL *tls = NULL;
SSL_CONNECTION *tls_conn = NULL;
tls = ossl_ssl_connection_new_int(port->channel_ctx, TLS_method());
if (tls == NULL || (tls_conn = SSL_CONNECTION_FROM_SSL(tls)) == NULL)
return NULL;
/* Override the user_ssl of the inner connection. */
tls_conn->s3.flags |= TLS1_FLAGS_QUIC;
/* Restrict options derived from the SSL_CTX. */
tls_conn->options &= OSSL_QUIC_PERMITTED_OPTIONS_CONN;
tls_conn->pha_enabled = 0;
return tls;
}
static QUIC_CHANNEL *port_make_channel(QUIC_PORT *port, SSL *tls, int is_server)
{
QUIC_CHANNEL_ARGS args = {0};
QUIC_CHANNEL *ch;
args.port = port;
args.is_server = is_server;
args.tls = (tls != NULL ? tls : port_new_handshake_layer(port));
args.lcidm = port->lcidm;
args.srtm = port->srtm;
if (args.tls == NULL)
return NULL;
#ifndef OPENSSL_NO_QLOG
args.use_qlog = 1; /* disabled if env not set */
args.qlog_title = args.tls->ctx->qlog_title;
#endif
ch = ossl_quic_channel_new(&args);
if (ch == NULL) {
if (tls == NULL)
SSL_free(args.tls);
return NULL;
}
return ch;
}
QUIC_CHANNEL *ossl_quic_port_create_outgoing(QUIC_PORT *port, SSL *tls)
{
return port_make_channel(port, tls, /*is_server=*/0);
}
QUIC_CHANNEL *ossl_quic_port_create_incoming(QUIC_PORT *port, SSL *tls)
{
QUIC_CHANNEL *ch;
assert(port->tserver_ch == NULL);
ch = port_make_channel(port, tls, /*is_server=*/1);
port->tserver_ch = ch;
port->is_server = 1;
return ch;
}
/*
* QUIC Port: Ticker-Mutator
* =========================
*/
/*
* Tick function for this port. This does everything related to network I/O for
* this port's network BIOs, and services child channels.
*/
void ossl_quic_port_subtick(QUIC_PORT *port, QUIC_TICK_RESULT *res,
uint32_t flags)
{
QUIC_CHANNEL *ch;
res->net_read_desired = 0;
res->net_write_desired = 0;
res->tick_deadline = ossl_time_infinite();
if (!port->engine->inhibit_tick) {
/* Handle any incoming data from network. */
if (ossl_quic_port_is_running(port))
port_rx_pre(port);
/* Iterate through all channels and service them. */
LIST_FOREACH(ch, ch, &port->channel_list) {
QUIC_TICK_RESULT subr = {0};
ossl_quic_channel_subtick(ch, &subr, flags);
ossl_quic_tick_result_merge_into(res, &subr);
}
}
}
/* Process incoming datagrams, if any. */
static void port_rx_pre(QUIC_PORT *port)
{
int ret;
/*
* Originally, this check (don't RX before we have sent anything if we are
* not a server, because there can't be anything) was just intended as a
* minor optimisation. However, it is actually required on Windows, and
* removing this check will cause Windows to break.
*
* The reason is that under Win32, recvfrom() does not work on a UDP socket
* which has not had bind() called (???). However, calling sendto() will
* automatically bind an unbound UDP socket. Therefore, if we call a Winsock
* recv-type function before calling a Winsock send-type function, that call
* will fail with WSAEINVAL, which we will regard as a permanent network
* error.
*
* Therefore, this check is essential as we do not require our API users to
* bind a socket first when using the API in client mode.
*/
if (!port->is_server && !port->have_sent_any_pkt)
return;
/*
* Get DEMUX to BIO_recvmmsg from the network and queue incoming datagrams
* to the appropriate QRX instances.
*/
ret = ossl_quic_demux_pump(port->demux);
if (ret == QUIC_DEMUX_PUMP_RES_PERMANENT_FAIL)
/*
* We don't care about transient failure, but permanent failure means we
* should tear down the port. All connections skip straight to the
* Terminated state as there is no point trying to send CONNECTION_CLOSE
* frames if the network BIO is not operating correctly.
*/
ossl_quic_port_raise_net_error(port, NULL);
}
/*
* Handles an incoming connection request and potentially decides to make a
* connection from it. If a new connection is made, the new channel is written
* to *new_ch.
*/
static void port_on_new_conn(QUIC_PORT *port, const BIO_ADDR *peer,
const QUIC_CONN_ID *scid,
const QUIC_CONN_ID *dcid,
QUIC_CHANNEL **new_ch)
{
if (port->tserver_ch != NULL) {
/* Specially assign to existing channel */
if (!ossl_quic_channel_on_new_conn(port->tserver_ch, peer, scid, dcid))
return;
*new_ch = port->tserver_ch;
port->tserver_ch = NULL;
return;
}
}
static int port_try_handle_stateless_reset(QUIC_PORT *port, const QUIC_URXE *e)
{
size_t i;
const unsigned char *data = ossl_quic_urxe_data(e);
void *opaque = NULL;
/*
* Perform some fast and cheap checks for a packet not being a stateless
* reset token. RFC 9000 s. 10.3 specifies this layout for stateless
* reset packets:
*
* Stateless Reset {
* Fixed Bits (2) = 1,
* Unpredictable Bits (38..),
* Stateless Reset Token (128),
* }
*
* It also specifies:
* However, endpoints MUST treat any packet ending in a valid
* stateless reset token as a Stateless Reset, as other QUIC
* versions might allow the use of a long header.
*
* We can rapidly check for the minimum length and that the first pair
* of bits in the first byte are 01 or 11.
*
* The function returns 1 if it is a stateless reset packet, 0 if it isn't
* and -1 if an error was encountered.
*/
if (e->data_len < QUIC_STATELESS_RESET_TOKEN_LEN + 5
|| (0100 & *data) != 0100)
return 0;
for (i = 0;; ++i) {
if (!ossl_quic_srtm_lookup(port->srtm,
(QUIC_STATELESS_RESET_TOKEN *)(data + e->data_len
- sizeof(QUIC_STATELESS_RESET_TOKEN)),
i, &opaque, NULL))
break;
assert(opaque != NULL);
ossl_quic_channel_on_stateless_reset((QUIC_CHANNEL *)opaque);
}
return i > 0;
}
/*
* This is called by the demux when we get a packet not destined for any known
* DCID.
*/
static void port_default_packet_handler(QUIC_URXE *e, void *arg,
const QUIC_CONN_ID *dcid)
{
QUIC_PORT *port = arg;
PACKET pkt;
QUIC_PKT_HDR hdr;
QUIC_CHANNEL *ch = NULL, *new_ch = NULL;
/* Don't handle anything if we are no longer running. */
if (!ossl_quic_port_is_running(port))
goto undesirable;
if (port_try_handle_stateless_reset(port, e))
goto undesirable;
if (dcid != NULL
&& ossl_quic_lcidm_lookup(port->lcidm, dcid, NULL,
(void **)&ch)) {
assert(ch != NULL);
ossl_quic_channel_inject(ch, e);
return;
}
/*
* If we have an incoming packet which doesn't match any existing connection
* we assume this is an attempt to make a new connection. Currently we
* require our caller to have precreated a latent 'incoming' channel via
* TSERVER which then gets turned into the new connection.
*
* TODO(QUIC SERVER): In the future we will construct channels dynamically
* in this case.
*/
if (port->tserver_ch == NULL)
goto undesirable;
/*
* We have got a packet for an unknown DCID. This might be an attempt to
* open a new connection.
*/
if (e->data_len < QUIC_MIN_INITIAL_DGRAM_LEN)
goto undesirable;
if (!PACKET_buf_init(&pkt, ossl_quic_urxe_data(e), e->data_len))
goto undesirable;
/*
* We set short_conn_id_len to SIZE_MAX here which will cause the decode
* operation to fail if we get a 1-RTT packet. This is fine since we only
* care about Initial packets.
*/
if (!ossl_quic_wire_decode_pkt_hdr(&pkt, SIZE_MAX, 1, 0, &hdr, NULL))
goto undesirable;
switch (hdr.version) {
case QUIC_VERSION_1:
break;
case QUIC_VERSION_NONE:
default:
/* Unknown version or proactive version negotiation request, bail. */
/* TODO(QUIC SERVER): Handle version negotiation on server side */
goto undesirable;
}
/*
* We only care about Initial packets which might be trying to establish a
* connection.
*/
if (hdr.type != QUIC_PKT_TYPE_INITIAL)
goto undesirable;
/*
* Try to process this as a valid attempt to initiate a connection.
*
* The channel will do all the LCID registration needed, but as an
* optimization inject this packet directly into the channel's QRX for
* processing without going through the DEMUX again.
*/
port_on_new_conn(port, &e->peer, &hdr.src_conn_id, &hdr.dst_conn_id,
&new_ch);
if (new_ch != NULL)
ossl_qrx_inject_urxe(new_ch->qrx, e);
return;
undesirable:
ossl_quic_demux_release_urxe(port->demux, e);
}
void ossl_quic_port_raise_net_error(QUIC_PORT *port,
QUIC_CHANNEL *triggering_ch)
{
QUIC_CHANNEL *ch;
if (!ossl_quic_port_is_running(port))
return;
/*
* Immediately capture any triggering error on the error stack, with a
* cover error.
*/
ERR_raise_data(ERR_LIB_SSL, SSL_R_QUIC_NETWORK_ERROR,
"port failed due to network BIO I/O error");
OSSL_ERR_STATE_save(port->err_state);
port_transition_failed(port);
/* Give the triggering channel (if any) the first notification. */
if (triggering_ch != NULL)
ossl_quic_channel_raise_net_error(triggering_ch);
LIST_FOREACH(ch, ch, &port->channel_list)
if (ch != triggering_ch)
ossl_quic_channel_raise_net_error(ch);
}
void ossl_quic_port_restore_err_state(const QUIC_PORT *port)
{
ERR_clear_error();
OSSL_ERR_STATE_restore(port->err_state);
}
