gstreamer/subprojects/gst-plugins-bad/ext/dtls/gstdtlsconnection.c
Sebastian Dröge c051982c0f dtlsconnection: Fix overflow in timeout calculation on systems with 32 bit time_t
If a timeout of more than 4295s was scheduled, the calculation would
overflow and a too short timeout would be used instead.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/6870>
2024-05-24 11:43:19 +00:00

1341 lines
37 KiB
C

/*
* Copyright (c) 2014, Ericsson AB. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice, this
* list of conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst.h>
#include "gstdtlsconnection.h"
#include "gstdtlsagent.h"
#include "gstdtlscertificate.h"
#ifdef __APPLE__
# define __AVAILABILITYMACROS__
# define DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER
#endif
#include <openssl/err.h>
#include <openssl/ssl.h>
#ifdef G_OS_WIN32
#include <winsock2.h>
#else
#include <string.h>
#include <errno.h>
#endif
GST_DEBUG_CATEGORY_STATIC (gst_dtls_connection_debug);
#define GST_CAT_DEFAULT gst_dtls_connection_debug
#define SRTP_KEY_LEN 16
#define SRTP_SALT_LEN 14
enum
{
SIGNAL_ON_ENCODER_KEY,
SIGNAL_ON_DECODER_KEY,
SIGNAL_ON_PEER_CERTIFICATE,
NUM_SIGNALS
};
static guint signals[NUM_SIGNALS];
enum
{
PROP_0,
PROP_AGENT,
PROP_CONNECTION_STATE,
NUM_PROPERTIES
};
static GParamSpec *properties[NUM_PROPERTIES];
static int connection_ex_index;
static void handle_timeout (gpointer data, gpointer user_data);
struct _GstDtlsConnectionPrivate
{
SSL *ssl;
BIO *bio;
gboolean is_client;
gboolean is_alive;
gboolean keys_exported;
GstDtlsConnectionState connection_state;
gboolean sent_close_notify;
gboolean received_close_notify;
GMutex mutex;
GCond condition;
gpointer bio_buffer;
gint bio_buffer_len;
gint bio_buffer_offset;
GstDtlsConnectionSendCallback send_callback;
gpointer send_callback_user_data;
GDestroyNotify send_callback_destroy_notify;
GstFlowReturn syscall_flow_return;
gboolean timeout_pending;
GThreadPool *thread_pool;
};
G_DEFINE_TYPE_WITH_CODE (GstDtlsConnection, gst_dtls_connection,
GST_TYPE_OBJECT, G_ADD_PRIVATE (GstDtlsConnection)
GST_DEBUG_CATEGORY_INIT (gst_dtls_connection_debug, "dtlsconnection", 0,
"DTLS Connection"));
static void gst_dtls_connection_finalize (GObject * gobject);
static void gst_dtls_connection_set_property (GObject *, guint prop_id,
const GValue *, GParamSpec *);
static void gst_dtls_connection_get_property (GObject *, guint prop_id,
GValue *, GParamSpec *);
static void log_state (GstDtlsConnection *, const gchar * str);
static gboolean export_srtp_keys (GstDtlsConnection *, GError ** err);
static GstFlowReturn openssl_poll (GstDtlsConnection *, gboolean * notify_state,
GError ** err);
static GstFlowReturn handle_error (GstDtlsConnection * self, int ret,
GstResourceError error_type, gboolean * notify_state, GError ** err);
static int openssl_verify_callback (int preverify_ok,
X509_STORE_CTX * x509_ctx);
static BIO_METHOD *BIO_s_gst_dtls_connection (void);
static int bio_method_write (BIO *, const char *data, int size);
static int bio_method_read (BIO *, char *out_buffer, int size);
static long bio_method_ctrl (BIO *, int cmd, long arg1, void *arg2);
static int bio_method_new (BIO *);
static int bio_method_free (BIO *);
static void
gst_dtls_connection_class_init (GstDtlsConnectionClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
gobject_class->set_property = gst_dtls_connection_set_property;
gobject_class->get_property = gst_dtls_connection_get_property;
connection_ex_index =
SSL_get_ex_new_index (0, (gpointer) "gstdtlsagent connection index", NULL,
NULL, NULL);
signals[SIGNAL_ON_DECODER_KEY] =
g_signal_new ("on-decoder-key", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, 0, NULL, NULL, NULL,
G_TYPE_NONE, 3, G_TYPE_POINTER, G_TYPE_UINT, G_TYPE_UINT);
signals[SIGNAL_ON_ENCODER_KEY] =
g_signal_new ("on-encoder-key", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, 0, NULL, NULL, NULL,
G_TYPE_NONE, 3, G_TYPE_POINTER, G_TYPE_UINT, G_TYPE_UINT);
signals[SIGNAL_ON_PEER_CERTIFICATE] =
g_signal_new ("on-peer-certificate", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, 0, NULL, NULL, NULL, G_TYPE_BOOLEAN, 1, G_TYPE_STRING);
properties[PROP_AGENT] =
g_param_spec_object ("agent",
"DTLS Agent",
"Agent to use in creation of the connection",
GST_TYPE_DTLS_AGENT,
G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS);
properties[PROP_CONNECTION_STATE] =
g_param_spec_enum ("connection-state",
"Connection State",
"Current connection state",
GST_DTLS_TYPE_CONNECTION_STATE,
GST_DTLS_CONNECTION_STATE_NEW, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
g_object_class_install_properties (gobject_class, NUM_PROPERTIES, properties);
_gst_dtls_init_openssl ();
gobject_class->finalize = gst_dtls_connection_finalize;
}
static void
gst_dtls_connection_init (GstDtlsConnection * self)
{
GstDtlsConnectionPrivate *priv;
self->priv = priv = gst_dtls_connection_get_instance_private (self);
priv->ssl = NULL;
priv->bio = NULL;
priv->is_client = FALSE;
priv->is_alive = TRUE;
priv->keys_exported = FALSE;
priv->bio_buffer = NULL;
priv->bio_buffer_len = 0;
priv->bio_buffer_offset = 0;
g_mutex_init (&priv->mutex);
g_cond_init (&priv->condition);
/* Thread pool for handling timeouts, we only need one thread for that
* really and share threads with all other thread pools around there as
* this is not going to happen very often */
priv->thread_pool = g_thread_pool_new (handle_timeout, self, 1, FALSE, NULL);
g_assert (priv->thread_pool);
priv->timeout_pending = FALSE;
}
static void
gst_dtls_connection_finalize (GObject * gobject)
{
GstDtlsConnection *self = GST_DTLS_CONNECTION (gobject);
GstDtlsConnectionPrivate *priv = self->priv;
g_thread_pool_free (priv->thread_pool, TRUE, TRUE);
priv->thread_pool = NULL;
SSL_free (priv->ssl);
priv->ssl = NULL;
if (priv->send_callback_destroy_notify)
priv->send_callback_destroy_notify (priv->send_callback_user_data);
g_mutex_clear (&priv->mutex);
g_cond_clear (&priv->condition);
GST_DEBUG_OBJECT (self, "finalized");
G_OBJECT_CLASS (gst_dtls_connection_parent_class)->finalize (gobject);
}
#if OPENSSL_VERSION_NUMBER < 0x10100001L
static void
BIO_set_data (BIO * bio, void *ptr)
{
bio->ptr = ptr;
}
static void *
BIO_get_data (BIO * bio)
{
return bio->ptr;
}
static void
BIO_set_shutdown (BIO * bio, int shutdown)
{
bio->shutdown = shutdown;
}
static void
BIO_set_init (BIO * bio, int init)
{
bio->init = init;
}
static X509 *
X509_STORE_CTX_get0_cert (X509_STORE_CTX * ctx)
{
return ctx->cert;
}
#endif
static void
gst_dtls_connection_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstDtlsConnection *self = GST_DTLS_CONNECTION (object);
GstDtlsAgent *agent;
GstDtlsConnectionPrivate *priv = self->priv;
SSL_CTX *ssl_context;
switch (prop_id) {
case PROP_AGENT:
g_return_if_fail (!priv->ssl);
agent = GST_DTLS_AGENT (g_value_get_object (value));
g_return_if_fail (GST_IS_DTLS_AGENT (agent));
ssl_context = _gst_dtls_agent_peek_context (agent);
priv->ssl = SSL_new (ssl_context);
g_return_if_fail (priv->ssl);
priv->bio = BIO_new (BIO_s_gst_dtls_connection ());
g_return_if_fail (priv->bio);
BIO_set_data (priv->bio, self);
SSL_set_bio (priv->ssl, priv->bio, priv->bio);
SSL_set_verify (priv->ssl,
SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
openssl_verify_callback);
SSL_set_ex_data (priv->ssl, connection_ex_index, self);
log_state (self, "connection created");
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (self, prop_id, pspec);
}
}
static void
gst_dtls_connection_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstDtlsConnection *self = GST_DTLS_CONNECTION (object);
GstDtlsConnectionPrivate *priv = self->priv;
switch (prop_id) {
case PROP_CONNECTION_STATE:
g_mutex_lock (&priv->mutex);
g_value_set_enum (value, priv->connection_state);
g_mutex_unlock (&priv->mutex);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (self, prop_id, pspec);
}
}
gboolean
gst_dtls_connection_start (GstDtlsConnection * self, gboolean is_client,
GError ** err)
{
GstDtlsConnectionPrivate *priv;
gboolean ret;
gboolean notify_state = FALSE;
priv = self->priv;
g_return_val_if_fail (priv->send_callback, FALSE);
g_return_val_if_fail (priv->ssl, FALSE);
g_return_val_if_fail (priv->bio, FALSE);
GST_TRACE_OBJECT (self, "locking @ start");
g_mutex_lock (&priv->mutex);
GST_TRACE_OBJECT (self, "locked @ start");
priv->is_alive = TRUE;
priv->bio_buffer = NULL;
priv->bio_buffer_len = 0;
priv->bio_buffer_offset = 0;
priv->keys_exported = FALSE;
priv->sent_close_notify = FALSE;
priv->received_close_notify = FALSE;
/* Client immediately starts connecting, the server waits for a client to
* start the handshake process */
priv->is_client = is_client;
if (priv->is_client) {
priv->connection_state = GST_DTLS_CONNECTION_STATE_CONNECTING;
notify_state = TRUE;
SSL_set_connect_state (priv->ssl);
} else {
if (priv->connection_state != GST_DTLS_CONNECTION_STATE_NEW) {
priv->connection_state = GST_DTLS_CONNECTION_STATE_NEW;
notify_state = TRUE;
}
SSL_set_accept_state (priv->ssl);
}
log_state (self, "initial state set");
ret = openssl_poll (self, &notify_state, err);
if (ret == GST_FLOW_EOS && err) {
*err =
g_error_new_literal (GST_RESOURCE_ERROR, GST_RESOURCE_ERROR_OPEN_WRITE,
"Connection closed");
}
log_state (self, "first poll done");
GST_TRACE_OBJECT (self, "unlocking @ start");
g_mutex_unlock (&priv->mutex);
if (notify_state) {
g_object_notify_by_pspec (G_OBJECT (self),
properties[PROP_CONNECTION_STATE]);
}
return ret == GST_FLOW_OK;
}
static void
handle_timeout (gpointer data, gpointer user_data)
{
GstDtlsConnection *self = user_data;
GstDtlsConnectionPrivate *priv;
gint ret;
gboolean notify_state = FALSE;
priv = self->priv;
g_mutex_lock (&priv->mutex);
priv->timeout_pending = FALSE;
if (priv->is_alive) {
ret = DTLSv1_handle_timeout (priv->ssl);
GST_DEBUG_OBJECT (self, "handle timeout returned %d, is_alive: %d", ret,
priv->is_alive);
if (ret < 0) {
GST_WARNING_OBJECT (self, "handling timeout failed");
} else if (ret > 0) {
log_state (self, "handling timeout before poll");
openssl_poll (self, &notify_state, NULL);
log_state (self, "handling timeout after poll");
}
}
g_mutex_unlock (&priv->mutex);
if (notify_state) {
g_object_notify_by_pspec (G_OBJECT (self),
properties[PROP_CONNECTION_STATE]);
}
}
static gboolean
schedule_timeout_handling (GstClock * clock, GstClockTime time, GstClockID id,
gpointer user_data)
{
GstDtlsConnection *self = user_data;
g_mutex_lock (&self->priv->mutex);
if (self->priv->is_alive && !self->priv->timeout_pending) {
self->priv->timeout_pending = TRUE;
GST_TRACE_OBJECT (self, "Schedule timeout now");
g_thread_pool_push (self->priv->thread_pool, GINT_TO_POINTER (0xc0ffee),
NULL);
}
g_mutex_unlock (&self->priv->mutex);
return TRUE;
}
static void
gst_dtls_connection_check_timeout_locked (GstDtlsConnection * self)
{
GstDtlsConnectionPrivate *priv;
struct timeval timeout;
gint64 end_time, wait_time;
g_return_if_fail (GST_IS_DTLS_CONNECTION (self));
priv = self->priv;
if (DTLSv1_get_timeout (priv->ssl, &timeout)) {
wait_time = ((gint64) timeout.tv_sec) * G_USEC_PER_SEC + timeout.tv_usec;
GST_DEBUG_OBJECT (self, "waiting for %" G_GINT64_FORMAT " usec", wait_time);
if (wait_time) {
GstClock *system_clock = gst_system_clock_obtain ();
GstClockID clock_id;
#ifndef G_DISABLE_ASSERT
GstClockReturn clock_return;
#endif
end_time = gst_clock_get_time (system_clock) + wait_time * GST_USECOND;
clock_id = gst_clock_new_single_shot_id (system_clock, end_time);
#ifndef G_DISABLE_ASSERT
clock_return =
#else
(void)
#endif
gst_clock_id_wait_async (clock_id, schedule_timeout_handling,
g_object_ref (self), (GDestroyNotify) g_object_unref);
g_assert (clock_return == GST_CLOCK_OK);
gst_clock_id_unref (clock_id);
gst_object_unref (system_clock);
} else {
if (self->priv->is_alive && !self->priv->timeout_pending) {
self->priv->timeout_pending = TRUE;
GST_TRACE_OBJECT (self, "Schedule timeout now");
g_thread_pool_push (self->priv->thread_pool, GINT_TO_POINTER (0xc0ffee),
NULL);
}
}
} else {
GST_DEBUG_OBJECT (self, "no timeout set");
}
}
void
gst_dtls_connection_check_timeout (GstDtlsConnection * self)
{
GstDtlsConnectionPrivate *priv;
g_return_if_fail (GST_IS_DTLS_CONNECTION (self));
priv = self->priv;
GST_TRACE_OBJECT (self, "locking @ start_timeout");
g_mutex_lock (&priv->mutex);
GST_TRACE_OBJECT (self, "locked @ start_timeout");
gst_dtls_connection_check_timeout_locked (self);
g_mutex_unlock (&priv->mutex);
GST_TRACE_OBJECT (self, "unlocking @ start_timeout");
}
void
gst_dtls_connection_stop (GstDtlsConnection * self)
{
gboolean notify_state = FALSE;
g_return_if_fail (GST_IS_DTLS_CONNECTION (self));
g_return_if_fail (self->priv->ssl);
g_return_if_fail (self->priv->bio);
GST_DEBUG_OBJECT (self, "stopping connection");
GST_TRACE_OBJECT (self, "locking @ stop");
g_mutex_lock (&self->priv->mutex);
GST_TRACE_OBJECT (self, "locked @ stop");
self->priv->is_alive = FALSE;
if (self->priv->connection_state != GST_DTLS_CONNECTION_STATE_FAILED
&& self->priv->connection_state != GST_DTLS_CONNECTION_STATE_CLOSED) {
self->priv->connection_state = GST_DTLS_CONNECTION_STATE_CLOSED;
notify_state = TRUE;
}
GST_TRACE_OBJECT (self, "signaling @ stop");
g_cond_signal (&self->priv->condition);
GST_TRACE_OBJECT (self, "signaled @ stop");
GST_TRACE_OBJECT (self, "unlocking @ stop");
g_mutex_unlock (&self->priv->mutex);
GST_DEBUG_OBJECT (self, "stopped connection");
if (notify_state) {
g_object_notify_by_pspec (G_OBJECT (self),
properties[PROP_CONNECTION_STATE]);
}
}
void
gst_dtls_connection_close (GstDtlsConnection * self)
{
gboolean notify_state = FALSE;
g_return_if_fail (GST_IS_DTLS_CONNECTION (self));
g_return_if_fail (self->priv->ssl);
g_return_if_fail (self->priv->bio);
GST_DEBUG_OBJECT (self, "closing connection");
GST_TRACE_OBJECT (self, "locking @ close");
g_mutex_lock (&self->priv->mutex);
GST_TRACE_OBJECT (self, "locked @ close");
if (self->priv->is_alive) {
self->priv->is_alive = FALSE;
g_cond_signal (&self->priv->condition);
}
if (self->priv->connection_state != GST_DTLS_CONNECTION_STATE_FAILED
&& self->priv->connection_state != GST_DTLS_CONNECTION_STATE_CLOSED) {
self->priv->connection_state = GST_DTLS_CONNECTION_STATE_CLOSED;
notify_state = TRUE;
}
GST_TRACE_OBJECT (self, "unlocking @ close");
g_mutex_unlock (&self->priv->mutex);
GST_DEBUG_OBJECT (self, "closed connection");
if (notify_state) {
g_object_notify_by_pspec (G_OBJECT (self),
properties[PROP_CONNECTION_STATE]);
}
}
void
gst_dtls_connection_set_send_callback (GstDtlsConnection * self,
GstDtlsConnectionSendCallback callback, gpointer user_data,
GDestroyNotify destroy_notify)
{
GstDtlsConnectionPrivate *priv;
g_return_if_fail (GST_IS_DTLS_CONNECTION (self));
priv = self->priv;
GST_TRACE_OBJECT (self, "locking @ set_send_callback");
g_mutex_lock (&priv->mutex);
GST_TRACE_OBJECT (self, "locked @ set_send_callback");
if (priv->send_callback_destroy_notify)
priv->send_callback_destroy_notify (priv->send_callback_user_data);
priv->send_callback = callback;
priv->send_callback_user_data = user_data;
priv->send_callback_destroy_notify = destroy_notify;
GST_TRACE_OBJECT (self, "unlocking @ set_send_callback");
g_mutex_unlock (&priv->mutex);
}
void
gst_dtls_connection_set_flow_return (GstDtlsConnection * self,
GstFlowReturn flow_ret)
{
g_return_if_fail (GST_IS_DTLS_CONNECTION (self));
self->priv->syscall_flow_return = flow_ret;
}
GstFlowReturn
gst_dtls_connection_process (GstDtlsConnection * self, gpointer data, gsize len,
gsize * written, GError ** err)
{
GstFlowReturn flow_ret = GST_FLOW_OK;
GstDtlsConnectionPrivate *priv;
int ret;
gboolean notify_state = FALSE;
g_return_val_if_fail (GST_IS_DTLS_CONNECTION (self), 0);
g_return_val_if_fail (self->priv->ssl, 0);
g_return_val_if_fail (self->priv->bio, 0);
priv = self->priv;
GST_TRACE_OBJECT (self, "locking @ process");
g_mutex_lock (&priv->mutex);
GST_TRACE_OBJECT (self, "locked @ process");
if (self->priv->received_close_notify
|| self->priv->connection_state == GST_DTLS_CONNECTION_STATE_CLOSED) {
GST_DEBUG_OBJECT (self, "Already received close_notify");
g_mutex_unlock (&priv->mutex);
return GST_FLOW_EOS;
}
if (self->priv->connection_state == GST_DTLS_CONNECTION_STATE_FAILED) {
GST_ERROR_OBJECT (self, "Had a fatal error before");
g_mutex_unlock (&priv->mutex);
if (err)
*err =
g_error_new_literal (GST_RESOURCE_ERROR, GST_RESOURCE_ERROR_READ,
"Had fatal error before");
return GST_FLOW_ERROR;
}
g_warn_if_fail (!priv->bio_buffer);
priv->bio_buffer = data;
priv->bio_buffer_len = len;
priv->bio_buffer_offset = 0;
log_state (self, "process start");
if (SSL_want_write (priv->ssl)) {
flow_ret = openssl_poll (self, &notify_state, err);
log_state (self, "process want write, after poll");
if (flow_ret != GST_FLOW_OK) {
g_mutex_unlock (&priv->mutex);
return flow_ret;
}
}
/* If we're a server and were in new state then by receiving the first data
* we would start the connection process */
if (!priv->is_client) {
if (self->priv->connection_state == GST_DTLS_CONNECTION_STATE_NEW) {
priv->connection_state = GST_DTLS_CONNECTION_STATE_CONNECTING;
notify_state = TRUE;
}
}
ret = SSL_read (priv->ssl, data, len);
*written = ret >= 0 ? ret : 0;
GST_DEBUG_OBJECT (self, "read result: %d", ret);
flow_ret =
handle_error (self, ret, GST_RESOURCE_ERROR_READ, &notify_state, err);
if (flow_ret == GST_FLOW_EOS) {
self->priv->received_close_notify = TRUE;
if (self->priv->connection_state != GST_DTLS_CONNECTION_STATE_FAILED
&& self->priv->connection_state != GST_DTLS_CONNECTION_STATE_CLOSED) {
self->priv->connection_state = GST_DTLS_CONNECTION_STATE_CLOSED;
notify_state = TRUE;
}
/* Notify about the connection being properly closed now if both
* sides did so */
if (self->priv->sent_close_notify && self->priv->send_callback)
self->priv->send_callback (self, NULL, 0, NULL);
g_mutex_unlock (&priv->mutex);
if (notify_state) {
g_object_notify_by_pspec (G_OBJECT (self),
properties[PROP_CONNECTION_STATE]);
}
return flow_ret;
} else if (flow_ret != GST_FLOW_OK) {
g_mutex_unlock (&priv->mutex);
if (notify_state) {
g_object_notify_by_pspec (G_OBJECT (self),
properties[PROP_CONNECTION_STATE]);
}
return flow_ret;
}
log_state (self, "process after read");
flow_ret = openssl_poll (self, &notify_state, err);
log_state (self, "process after poll");
GST_TRACE_OBJECT (self, "unlocking @ process");
g_mutex_unlock (&priv->mutex);
if (notify_state) {
g_object_notify_by_pspec (G_OBJECT (self),
properties[PROP_CONNECTION_STATE]);
}
return flow_ret;
}
GstFlowReturn
gst_dtls_connection_send (GstDtlsConnection * self, gconstpointer data,
gsize len, gsize * written, GError ** err)
{
GstFlowReturn flow_ret;
int ret = 0;
gboolean notify_state = FALSE;
g_return_val_if_fail (GST_IS_DTLS_CONNECTION (self), 0);
g_return_val_if_fail (self->priv->ssl, 0);
g_return_val_if_fail (self->priv->bio, 0);
GST_TRACE_OBJECT (self, "locking @ send");
g_mutex_lock (&self->priv->mutex);
GST_TRACE_OBJECT (self, "locked @ send");
if (self->priv->connection_state == GST_DTLS_CONNECTION_STATE_FAILED) {
GST_ERROR_OBJECT (self, "Had a fatal error before");
g_mutex_unlock (&self->priv->mutex);
if (err)
*err =
g_error_new_literal (GST_RESOURCE_ERROR, GST_RESOURCE_ERROR_WRITE,
"Had fatal error before");
return GST_FLOW_ERROR;
}
if (self->priv->sent_close_notify) {
len = 0;
GST_DEBUG_OBJECT (self, "Not sending new data after close_notify");
}
if (len == 0) {
if (written)
*written = 0;
GST_DEBUG_OBJECT (self, "Sending close_notify");
ret = SSL_shutdown (self->priv->ssl);
if (self->priv->connection_state != GST_DTLS_CONNECTION_STATE_CLOSED &&
self->priv->connection_state != GST_DTLS_CONNECTION_STATE_FAILED) {
self->priv->connection_state = GST_DTLS_CONNECTION_STATE_CLOSED;
notify_state = TRUE;
}
if (ret == 1) {
GST_LOG_OBJECT (self, "received peer close_notify already");
self->priv->received_close_notify = TRUE;
flow_ret = GST_FLOW_EOS;
} else if (ret == 0) {
GST_LOG_OBJECT (self, "did not receive peer close_notify yet");
flow_ret = GST_FLOW_OK;
} else {
flow_ret =
handle_error (self, ret, GST_RESOURCE_ERROR_WRITE, &notify_state,
err);
}
} else if (SSL_is_init_finished (self->priv->ssl)) {
GST_DEBUG_OBJECT (self, "sending data of %" G_GSIZE_FORMAT " B", len);
ret = SSL_write (self->priv->ssl, data, len);
if (ret <= 0) {
if (written)
*written = 0;
flow_ret =
handle_error (self, ret, GST_RESOURCE_ERROR_WRITE, &notify_state,
err);
} else {
if (written)
*written = ret;
flow_ret = GST_FLOW_OK;
}
} else {
if (written)
*written = ret;
GST_WARNING_OBJECT (self,
"tried to send data before handshake was complete");
if (err)
*err =
g_error_new_literal (GST_RESOURCE_ERROR, GST_RESOURCE_ERROR_WRITE,
"Tried to send data before handshake was complete");
flow_ret = GST_FLOW_ERROR;
}
GST_TRACE_OBJECT (self, "unlocking @ send");
g_mutex_unlock (&self->priv->mutex);
if (notify_state) {
g_object_notify_by_pspec (G_OBJECT (self),
properties[PROP_CONNECTION_STATE]);
}
return flow_ret;
}
/*
###### ####### ## ##
## ## ## ## ### ##
## ## ## #### ##
## ## ## ## ## ##
## ## ## ## ####
## ## ## ## ## ###
###### ####### ## ##
*/
static void
log_state (GstDtlsConnection * self, const gchar * str)
{
GstDtlsConnectionPrivate *priv = self->priv;
guint states = 0;
states |= (!!SSL_is_init_finished (priv->ssl) << 0);
states |= (!!SSL_in_init (priv->ssl) << 4);
states |= (!!SSL_in_before (priv->ssl) << 8);
states |= (!!SSL_in_connect_init (priv->ssl) << 12);
states |= (!!SSL_in_accept_init (priv->ssl) << 16);
states |= (!!SSL_want_write (priv->ssl) << 20);
states |= (!!SSL_want_read (priv->ssl) << 24);
#if OPENSSL_VERSION_NUMBER < 0x10100001L
GST_LOG_OBJECT (self, "%s: role=%s buf=(%d,%p:%d/%d) %x|%x %s",
str,
priv->is_client ? "client" : "server",
pqueue_size (priv->ssl->d1->sent_messages),
priv->bio_buffer,
priv->bio_buffer_offset,
priv->bio_buffer_len,
states, SSL_get_state (priv->ssl), SSL_state_string_long (priv->ssl));
#else
GST_LOG_OBJECT (self, "%s: role=%s buf=(%p:%d/%d) %x|%x %s",
str,
priv->is_client ? "client" : "server",
priv->bio_buffer,
priv->bio_buffer_offset,
priv->bio_buffer_len,
states, SSL_get_state (priv->ssl), SSL_state_string_long (priv->ssl));
#endif
}
static gboolean
export_srtp_keys (GstDtlsConnection * self, GError ** err)
{
typedef struct
{
guint8 v[SRTP_KEY_LEN];
} Key;
typedef struct
{
guint8 v[SRTP_SALT_LEN];
} Salt;
struct
{
Key client_key;
Key server_key;
Salt client_salt;
Salt server_salt;
} exported_keys;
struct
{
Key key;
Salt salt;
} client_key, server_key;
SRTP_PROTECTION_PROFILE *profile;
GstDtlsSrtpCipher cipher;
GstDtlsSrtpAuth auth;
gint success;
static gchar export_string[] = "EXTRACTOR-dtls_srtp";
success = SSL_export_keying_material (self->priv->ssl,
(gpointer) & exported_keys, 60, export_string, strlen (export_string),
NULL, 0, 0);
if (!success) {
GST_WARNING_OBJECT (self, "Failed to export SRTP keys");
if (err)
*err =
g_error_new_literal (GST_RESOURCE_ERROR, GST_RESOURCE_ERROR_READ,
"Failed to export SRTP keys");
return FALSE;
}
profile = SSL_get_selected_srtp_profile (self->priv->ssl);
if (!profile) {
GST_WARNING_OBJECT (self,
"No SRTP capabilities negotiated during handshake");
if (err)
*err =
g_error_new_literal (GST_RESOURCE_ERROR, GST_RESOURCE_ERROR_READ,
"No SRTP capabilities negotiated during handshake");
return FALSE;
}
GST_INFO_OBJECT (self, "keys received, profile is %s", profile->name);
switch (profile->id) {
case SRTP_AES128_CM_SHA1_80:
cipher = GST_DTLS_SRTP_CIPHER_AES_128_ICM;
auth = GST_DTLS_SRTP_AUTH_HMAC_SHA1_80;
break;
case SRTP_AES128_CM_SHA1_32:
cipher = GST_DTLS_SRTP_CIPHER_AES_128_ICM;
auth = GST_DTLS_SRTP_AUTH_HMAC_SHA1_32;
break;
default:
GST_WARNING_OBJECT (self,
"Invalid/unsupported crypto suite set by handshake");
if (err)
*err =
g_error_new_literal (GST_RESOURCE_ERROR, GST_RESOURCE_ERROR_READ,
"Invalid/unsupported crypto suite set by handshake");
return FALSE;
}
client_key.key = exported_keys.client_key;
server_key.key = exported_keys.server_key;
client_key.salt = exported_keys.client_salt;
server_key.salt = exported_keys.server_salt;
if (self->priv->is_client) {
g_signal_emit (self, signals[SIGNAL_ON_ENCODER_KEY], 0, &client_key, cipher,
auth);
g_signal_emit (self, signals[SIGNAL_ON_DECODER_KEY], 0, &server_key,
cipher, auth);
} else {
g_signal_emit (self, signals[SIGNAL_ON_ENCODER_KEY], 0, &server_key,
cipher, auth);
g_signal_emit (self, signals[SIGNAL_ON_DECODER_KEY], 0, &client_key, cipher,
auth);
}
self->priv->keys_exported = TRUE;
return TRUE;
}
static int
ssl_warn_cb (const char *str, size_t len, void *u)
{
GstDtlsConnection *self = u;
GST_WARNING_OBJECT (self, "ssl error: %s", str);
return 0;
}
static int
ssl_err_cb (const char *str, size_t len, void *u)
{
GstDtlsConnection *self = u;
GST_ERROR_OBJECT (self, "ssl error: %s", str);
return 0;
}
static GstFlowReturn
handle_error (GstDtlsConnection * self, int ret, GstResourceError error_type,
gboolean * notify_state, GError ** err)
{
int error;
error = SSL_get_error (self->priv->ssl, ret);
switch (error) {
case SSL_ERROR_NONE:
GST_TRACE_OBJECT (self, "No error");
return GST_FLOW_OK;
case SSL_ERROR_SSL:
GST_ERROR_OBJECT (self, "Fatal SSL error");
if (self->priv->connection_state != GST_DTLS_CONNECTION_STATE_FAILED) {
self->priv->connection_state = GST_DTLS_CONNECTION_STATE_FAILED;
*notify_state = TRUE;
}
ERR_print_errors_cb (ssl_err_cb, self);
if (err)
*err =
g_error_new_literal (GST_RESOURCE_ERROR, error_type,
"Fatal SSL error");
return GST_FLOW_ERROR;
case SSL_ERROR_ZERO_RETURN:
GST_LOG_OBJECT (self, "Connection was closed");
return GST_FLOW_EOS;
case SSL_ERROR_WANT_READ:
GST_LOG_OBJECT (self, "SSL wants read");
return GST_FLOW_OK;
case SSL_ERROR_WANT_WRITE:
GST_LOG_OBJECT (self, "SSL wants write");
return GST_FLOW_OK;
case SSL_ERROR_SYSCALL:{
GstFlowReturn rc = GST_FLOW_OK;
/* OpenSSL shouldn't be making real system calls, so we can safely
* ignore syscall errors. System interactions should happen through
* our BIO.
*/
if (error_type == GST_RESOURCE_ERROR_WRITE) {
rc = self->priv->syscall_flow_return;
}
GST_DEBUG_OBJECT (self,
"OpenSSL reported a syscall error. flow_return=%i", rc);
return rc;
}
default:
if (self->priv->connection_state != GST_DTLS_CONNECTION_STATE_FAILED) {
self->priv->connection_state = GST_DTLS_CONNECTION_STATE_FAILED;
*notify_state = TRUE;
}
GST_ERROR_OBJECT (self, "Unknown SSL error: %d, ret: %d", error, ret);
if (err)
*err =
g_error_new (GST_RESOURCE_ERROR, error_type,
"Unknown SSL error: %d, ret: %d", error, ret);
return GST_FLOW_ERROR;
}
}
static GstFlowReturn
openssl_poll (GstDtlsConnection * self, gboolean * notify_state, GError ** err)
{
int ret;
GstFlowReturn flow_ret;
log_state (self, "poll: before handshake");
ERR_clear_error ();
ret = SSL_do_handshake (self->priv->ssl);
log_state (self, "poll: after handshake");
switch (ret) {
case 1:
if (!self->priv->keys_exported) {
GST_INFO_OBJECT (self,
"handshake just completed successfully, exporting keys");
if (!export_srtp_keys (self, err))
return GST_FLOW_ERROR;
if (self->priv->connection_state != GST_DTLS_CONNECTION_STATE_FAILED
&& self->priv->connection_state != GST_DTLS_CONNECTION_STATE_CLOSED
&& self->priv->connection_state !=
GST_DTLS_CONNECTION_STATE_CONNECTED) {
self->priv->connection_state = GST_DTLS_CONNECTION_STATE_CONNECTED;
*notify_state = TRUE;
}
} else {
GST_INFO_OBJECT (self, "handshake is completed");
}
return GST_FLOW_OK;
case 0:
GST_DEBUG_OBJECT (self, "do_handshake encountered EOF");
break;
case -1:
GST_DEBUG_OBJECT (self, "do_handshake encountered potential BIO error");
break;
default:
GST_DEBUG_OBJECT (self, "do_handshake returned %d", ret);
break;
}
flow_ret =
handle_error (self, ret, GST_RESOURCE_ERROR_OPEN_WRITE, notify_state,
err);
ERR_print_errors_cb (ssl_warn_cb, self);
return flow_ret;
}
static int
openssl_verify_callback (int preverify_ok, X509_STORE_CTX * x509_ctx)
{
GstDtlsConnection *self;
SSL *ssl;
BIO *bio;
gchar *pem = NULL;
gboolean accepted = FALSE;
ssl =
X509_STORE_CTX_get_ex_data (x509_ctx,
SSL_get_ex_data_X509_STORE_CTX_idx ());
self = SSL_get_ex_data (ssl, connection_ex_index);
g_return_val_if_fail (GST_IS_DTLS_CONNECTION (self), FALSE);
pem = _gst_dtls_x509_to_pem (X509_STORE_CTX_get0_cert (x509_ctx));
if (!pem) {
GST_WARNING_OBJECT (self,
"failed to convert received certificate to pem format");
} else {
bio = BIO_new (BIO_s_mem ());
if (bio) {
gchar buffer[2048];
gint len;
len =
X509_NAME_print_ex (bio,
X509_get_subject_name (X509_STORE_CTX_get0_cert (x509_ctx)), 1,
XN_FLAG_MULTILINE);
BIO_read (bio, buffer, len);
buffer[len] = '\0';
GST_DEBUG_OBJECT (self, "Peer certificate received:\n%s", buffer);
BIO_free (bio);
} else {
GST_DEBUG_OBJECT (self, "failed to create certificate print membio");
}
g_signal_emit (self, signals[SIGNAL_ON_PEER_CERTIFICATE], 0, pem,
&accepted);
g_free (pem);
}
return accepted;
}
/*
######## #### #######
## ## ## ## ##
## ## ## ## ##
######## ## ## ##
## ## ## ## ##
## ## ## ## ##
######## #### #######
*/
#if OPENSSL_VERSION_NUMBER < 0x10100001L
static BIO_METHOD custom_bio_methods = {
BIO_TYPE_BIO,
"stream",
bio_method_write,
bio_method_read,
NULL,
NULL,
bio_method_ctrl,
bio_method_new,
bio_method_free,
NULL,
};
static BIO_METHOD *
BIO_s_gst_dtls_connection (void)
{
return &custom_bio_methods;
}
#else
static BIO_METHOD *custom_bio_methods;
static BIO_METHOD *
BIO_s_gst_dtls_connection (void)
{
if (custom_bio_methods != NULL)
return custom_bio_methods;
custom_bio_methods = BIO_meth_new (BIO_TYPE_BIO, "stream");
if (custom_bio_methods == NULL
|| !BIO_meth_set_write (custom_bio_methods, bio_method_write)
|| !BIO_meth_set_read (custom_bio_methods, bio_method_read)
|| !BIO_meth_set_ctrl (custom_bio_methods, bio_method_ctrl)
|| !BIO_meth_set_create (custom_bio_methods, bio_method_new)
|| !BIO_meth_set_destroy (custom_bio_methods, bio_method_free)) {
BIO_meth_free (custom_bio_methods);
return NULL;
}
return custom_bio_methods;
}
#endif
static int
bio_method_write (BIO * bio, const char *data, int size)
{
GstDtlsConnection *self = GST_DTLS_CONNECTION (BIO_get_data (bio));
gboolean ret = TRUE;
GST_LOG_OBJECT (self, "BIO: writing %d", size);
self->priv->syscall_flow_return = GST_FLOW_OK;
if (self->priv->send_callback)
ret = self->priv->send_callback (self, data, size,
self->priv->send_callback_user_data);
return ret ? size : -1;
}
static int
bio_method_read (BIO * bio, char *out_buffer, int size)
{
GstDtlsConnection *self = GST_DTLS_CONNECTION (BIO_get_data (bio));
GstDtlsConnectionPrivate *priv = self->priv;
guint internal_size;
gint copy_size;
internal_size = priv->bio_buffer_len - priv->bio_buffer_offset;
if (!priv->bio_buffer) {
GST_LOG_OBJECT (self, "BIO: EOF");
return 0;
}
if (!out_buffer || size <= 0) {
GST_WARNING_OBJECT (self, "BIO: read got invalid arguments");
if (internal_size) {
BIO_set_retry_read (bio);
}
return internal_size;
}
if (size > internal_size) {
copy_size = internal_size;
} else {
copy_size = size;
}
GST_DEBUG_OBJECT (self,
"reading %d/%d bytes %d at offset %d, output buff size is %d", copy_size,
priv->bio_buffer_len, internal_size, priv->bio_buffer_offset, size);
memcpy (out_buffer, (guint8 *) priv->bio_buffer + priv->bio_buffer_offset,
copy_size);
priv->bio_buffer_offset += copy_size;
if (priv->bio_buffer_len == priv->bio_buffer_offset) {
priv->bio_buffer = NULL;
}
return copy_size;
}
static long
bio_method_ctrl (BIO * bio, int cmd, long arg1, void *arg2)
{
GstDtlsConnection *self = GST_DTLS_CONNECTION (BIO_get_data (bio));
GstDtlsConnectionPrivate *priv = self->priv;
switch (cmd) {
case BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT:
case BIO_CTRL_DGRAM_SET_RECV_TIMEOUT:
GST_LOG_OBJECT (self, "BIO: Timeout set");
gst_dtls_connection_check_timeout_locked (self);
return 1;
case BIO_CTRL_RESET:
priv->bio_buffer = NULL;
priv->bio_buffer_len = 0;
priv->bio_buffer_offset = 0;
GST_LOG_OBJECT (self, "BIO: EOF reset");
return 1;
case BIO_CTRL_EOF:{
gint eof = priv->is_alive == FALSE;
GST_LOG_OBJECT (self, "BIO: EOF query returned %d", eof);
return eof;
}
case BIO_CTRL_WPENDING:
GST_LOG_OBJECT (self, "BIO: pending write");
return 1;
case BIO_CTRL_PENDING:{
gint pending = priv->bio_buffer_len - priv->bio_buffer_offset;
GST_LOG_OBJECT (self, "BIO: %d bytes pending", pending);
return pending;
}
case BIO_CTRL_FLUSH:
GST_LOG_OBJECT (self, "BIO: flushing");
return 1;
case BIO_CTRL_DGRAM_QUERY_MTU:
GST_DEBUG_OBJECT (self, "BIO: MTU query, returning 0...");
return 0;
case BIO_CTRL_DGRAM_MTU_EXCEEDED:
GST_WARNING_OBJECT (self, "BIO: MTU exceeded");
return 0;
default:
GST_LOG_OBJECT (self, "BIO: unhandled ctrl, %d", cmd);
return 0;
}
}
static int
bio_method_new (BIO * bio)
{
GST_LOG_OBJECT (NULL, "BIO: new");
BIO_set_shutdown (bio, 0);
BIO_set_init (bio, 1);
return 1;
}
static int
bio_method_free (BIO * bio)
{
if (!bio) {
GST_LOG_OBJECT (NULL, "BIO free called with null bio");
return 0;
}
GST_LOG_OBJECT (GST_DTLS_CONNECTION (BIO_get_data (bio)), "BIO free");
return 0;
}
GType
gst_dtls_connection_state_get_type (void)
{
static GType type = 0;
static const GEnumValue values[] = {
{GST_DTLS_CONNECTION_STATE_NEW, "New connection", "new"},
{GST_DTLS_CONNECTION_STATE_CLOSED, "Closed connection on either side",
"closed"},
{GST_DTLS_CONNECTION_STATE_FAILED, "Failed connection", "failed"},
{GST_DTLS_CONNECTION_STATE_CONNECTING, "Connecting", "connecting"},
{GST_DTLS_CONNECTION_STATE_CONNECTED, "Successfully connected",
"connected"},
{0, NULL, NULL},
};
if (!type) {
type = g_enum_register_static ("GstDtlsConnectionState", values);
}
return type;
}