[FFmpeg-devel] [PATCH] avformat: implement SChannel SSP TLS protocol
Hendrik Leppkes
h.leppkes at gmail.com
Wed Oct 21 13:52:46 CEST 2015
This implementation does not support TLS listen sockets and loading
CA/Certs from files.
The Windows API does not support loading PEM certs, and would either
require a manual loader or instead be limited to loading Windows PFX
certificates
TLS listen sockets would have to be implemented quite separately, as many
of the APIs are different for server-mode (as opposed to client mode).
---
Because of the limitations in comparison to OpenSSL or GnuTLS,
we might make this implementation not active by default, if someone feels
like thats a better course of action.
configure | 20 +-
libavformat/Makefile | 1 +
libavformat/allformats.c | 1 +
libavformat/tls.h | 2 +-
libavformat/tls_schannel.c | 601 +++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 621 insertions(+), 4 deletions(-)
create mode 100644 libavformat/tls_schannel.c
diff --git a/configure b/configure
index 5e7ded1..6b9b99c 100755
--- a/configure
+++ b/configure
@@ -280,6 +280,8 @@ External library support:
--enable-opengl enable OpenGL rendering [no]
--enable-openssl enable openssl, needed for https support
if gnutls is not used [no]
+ --disable-schannel disable SChannel SSP, needed for TLS support on
+ Windows if openssl and gnutls are not used [autodetect]
--disable-sdl disable sdl [autodetect]
--disable-securetransport disable Secure Transport, needed for TLS support
on OSX if openssl and gnutls are not used [autodetect]
@@ -1465,6 +1467,7 @@ EXTERNAL_LIBRARY_LIST="
opencl
opengl
openssl
+ schannel
sdl
securetransport
x11grab
@@ -2754,13 +2757,15 @@ sctp_protocol_deps="struct_sctp_event_subscribe"
sctp_protocol_select="network"
srtp_protocol_select="rtp_protocol"
tcp_protocol_select="network"
-tls_gnutls_protocol_deps="gnutls !tls_securetransport_protocol"
+tls_gnutls_protocol_deps="gnutls !tls_schannel_protocol !tls_securetransport_protocol"
tls_gnutls_protocol_select="tcp_protocol"
-tls_openssl_protocol_deps="openssl !tls_securetransport_protocol !tls_gnutls_protocol"
+tls_openssl_protocol_deps="openssl !tls_schannel_protocol !tls_securetransport_protocol !tls_gnutls_protocol"
tls_openssl_protocol_select="tcp_protocol"
+tls_schannel_protocol_deps="schannel"
+tls_schannel_protocol_select="tcp_protocol"
tls_securetransport_protocol_deps="securetransport"
tls_securetransport_protocol_select="tcp_protocol"
-tls_protocol_deps_any="tls_securetransport_protocol tls_gnutls_protocol tls_openssl_protocol"
+tls_protocol_deps_any="tls_schannel_protocol tls_securetransport_protocol tls_gnutls_protocol tls_openssl_protocol"
udp_protocol_select="network"
udplite_protocol_select="network"
unix_protocol_deps="sys_un_h"
@@ -5501,6 +5506,15 @@ disabled securetransport || { check_func SecIdentityCreate "-Wl,-framework,CoreF
check_lib2 "Security/SecureTransport.h Security/Security.h" "SSLCreateContext SecItemImport" "-Wl,-framework,CoreFoundation -Wl,-framework,Security" &&
enable securetransport; }
+if ! disabled schannel; then
+check_cc <<EOF && enable schannel && add_extralibs -lSecur32
+#define SECURITY_WIN32
+#include <windows.h>
+#include <Security.h>
+int main(void) { InitializeSecurityContext(NULL, NULL, NULL, 0, 0, 0, NULL, 0, NULL, NULL, NULL, NULL); return 0; }
+EOF
+fi
+
makeinfo --version > /dev/null 2>&1 && enable makeinfo || disable makeinfo
enabled makeinfo \
&& [ 0$(makeinfo --version | grep "texinfo" | sed 's/.*texinfo[^0-9]*\([0-9]*\)\..*/\1/') -ge 5 ] \
diff --git a/libavformat/Makefile b/libavformat/Makefile
index ded2d54..b2d6057 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -535,6 +535,7 @@ OBJS-$(CONFIG_SUBFILE_PROTOCOL) += subfile.o
OBJS-$(CONFIG_TCP_PROTOCOL) += tcp.o
OBJS-$(CONFIG_TLS_GNUTLS_PROTOCOL) += tls_gnutls.o tls.o
OBJS-$(CONFIG_TLS_OPENSSL_PROTOCOL) += tls_openssl.o tls.o
+OBJS-$(CONFIG_TLS_SCHANNEL_PROTOCOL) += tls_schannel.o tls.o
OBJS-$(CONFIG_TLS_SECURETRANSPORT_PROTOCOL) += tls_securetransport.o tls.o
OBJS-$(CONFIG_UDP_PROTOCOL) += udp.o
OBJS-$(CONFIG_UDPLITE_PROTOCOL) += udp.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index 40fea8e..dad2644 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -387,6 +387,7 @@ void av_register_all(void)
REGISTER_PROTOCOL(SRTP, srtp);
REGISTER_PROTOCOL(SUBFILE, subfile);
REGISTER_PROTOCOL(TCP, tcp);
+ REGISTER_PROTOCOL(TLS_SCHANNEL, tls_schannel);
REGISTER_PROTOCOL(TLS_SECURETRANSPORT, tls_securetransport);
REGISTER_PROTOCOL(TLS_GNUTLS, tls_gnutls);
REGISTER_PROTOCOL(TLS_OPENSSL, tls_openssl);
diff --git a/libavformat/tls.h b/libavformat/tls.h
index 2a36f34..0326ef7 100644
--- a/libavformat/tls.h
+++ b/libavformat/tls.h
@@ -26,7 +26,7 @@
#include "url.h"
#include "libavutil/opt.h"
-#define CONFIG_TLS_PROTOCOL (CONFIG_TLS_GNUTLS_PROTOCOL | CONFIG_TLS_OPENSSL_PROTOCOL | CONFIG_TLS_SECURETRANSPORT_PROTOCOL)
+#define CONFIG_TLS_PROTOCOL (CONFIG_TLS_GNUTLS_PROTOCOL | CONFIG_TLS_OPENSSL_PROTOCOL | CONFIG_TLS_SECURETRANSPORT_PROTOCOL | CONFIG_TLS_SCHANNEL_PROTOCOL)
typedef struct TLSShared {
char *ca_file;
diff --git a/libavformat/tls_schannel.c b/libavformat/tls_schannel.c
new file mode 100644
index 0000000..d8a35bc
--- /dev/null
+++ b/libavformat/tls_schannel.c
@@ -0,0 +1,601 @@
+/*
+ * Copyright (c) 2015 Hendrik Leppkes
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/** Based on the CURL SChannel module */
+
+#include "avformat.h"
+#include "internal.h"
+#include "network.h"
+#include "os_support.h"
+#include "url.h"
+#include "tls.h"
+
+#define SECURITY_WIN32
+#include <security.h>
+#include <schnlsp.h>
+
+#define SCHANNEL_INITIAL_BUFFER_SIZE 4096
+#define SCHANNEL_FREE_BUFFER_SIZE 1024
+
+#ifndef SECBUFFER_ALERT
+#define SECBUFFER_ALERT 17
+#endif
+
+typedef struct TLSContext {
+ const AVClass *class;
+ TLSShared tls_shared;
+
+ CredHandle cred_handle;
+ TimeStamp cred_timestamp;
+
+ CtxtHandle ctxt_handle;
+ TimeStamp ctxt_timestamp;
+
+ ULONG request_flags;
+ ULONG context_flags;
+
+ uint8_t *enc_buf;
+ int enc_buf_size;
+ int enc_buf_offset;
+
+ uint8_t *dec_buf;
+ int dec_buf_size;
+ int dec_buf_offset;
+
+ SecPkgContext_StreamSizes Sizes;
+
+ int connected;
+ int connection_closed;
+ int sspi_close_notify;
+} TLSContext;
+
+static void InitSecBuffer(SecBuffer *buffer, unsigned long BufType,
+ void *BufDataPtr, unsigned long BufByteSize)
+{
+ buffer->cbBuffer = BufByteSize;
+ buffer->BufferType = BufType;
+ buffer->pvBuffer = BufDataPtr;
+}
+
+static void InitSecBufferDesc(SecBufferDesc *desc, SecBuffer *BufArr,
+ unsigned long NumArrElem)
+{
+ desc->ulVersion = SECBUFFER_VERSION;
+ desc->pBuffers = BufArr;
+ desc->cBuffers = NumArrElem;
+}
+
+static int tls_client_handshake_loop(URLContext *h, int initial)
+{
+ TLSContext *c = h->priv_data;
+ TLSShared *s = &c->tls_shared;
+ SECURITY_STATUS sspi_ret = SEC_I_CONTINUE_NEEDED;
+ SecBuffer outbuf[3];
+ SecBufferDesc outbuf_desc;
+ SecBuffer inbuf[2];
+ SecBufferDesc inbuf_desc;
+ int i, ret = 0, read_data = initial;
+
+ if (c->enc_buf == NULL) {
+ c->enc_buf_offset = 0;
+ c->enc_buf_size = SCHANNEL_INITIAL_BUFFER_SIZE;
+ ret = av_reallocp(&c->enc_buf, c->enc_buf_size);
+ if (ret < 0)
+ goto fail;
+ }
+
+ if (c->dec_buf == NULL) {
+ c->dec_buf_offset = 0;
+ c->dec_buf_size = SCHANNEL_INITIAL_BUFFER_SIZE;
+ ret = av_reallocp(&c->dec_buf, c->dec_buf_size);
+ if (ret < 0)
+ goto fail;
+ }
+
+ while (1)
+ {
+ if (c->enc_buf_size - c->enc_buf_offset < SCHANNEL_FREE_BUFFER_SIZE) {
+ c->enc_buf_size = c->enc_buf_offset + SCHANNEL_FREE_BUFFER_SIZE;
+ ret = av_reallocp(&c->enc_buf, c->enc_buf_size);
+ if (ret < 0)
+ goto fail;
+ }
+
+ if (read_data) {
+ ret = ffurl_read(c->tls_shared.tcp, c->enc_buf + c->enc_buf_offset,
+ c->enc_buf_size - c->enc_buf_offset);
+ if (ret < 0) {
+ av_log(h, AV_LOG_ERROR, "Failed to read handshake response\n");
+ goto fail;
+ }
+ c->enc_buf_offset += ret;
+ }
+
+ /* input buffers */
+ InitSecBuffer(&inbuf[0], SECBUFFER_TOKEN, av_malloc(c->enc_buf_offset), c->enc_buf_offset);
+ InitSecBuffer(&inbuf[1], SECBUFFER_EMPTY, NULL, 0);
+ InitSecBufferDesc(&inbuf_desc, inbuf, 2);
+
+ if (inbuf[0].pvBuffer == NULL) {
+ av_log(h, AV_LOG_ERROR, "Failed to allocate input buffer\n");
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+
+ memcpy(inbuf[0].pvBuffer, c->enc_buf, c->enc_buf_offset);
+
+ /* output buffers */
+ InitSecBuffer(&outbuf[0], SECBUFFER_TOKEN, NULL, 0);
+ InitSecBuffer(&outbuf[1], SECBUFFER_ALERT, NULL, 0);
+ InitSecBuffer(&outbuf[2], SECBUFFER_EMPTY, NULL, 0);
+ InitSecBufferDesc(&outbuf_desc, outbuf, 3);
+
+ sspi_ret = InitializeSecurityContext(&c->cred_handle, &c->ctxt_handle, s->host, c->request_flags,
+ 0, 0, &inbuf_desc, 0, NULL, &outbuf_desc, &c->context_flags,
+ &c->ctxt_timestamp);
+ av_freep(&inbuf[0].pvBuffer);
+
+ if (sspi_ret == SEC_E_INCOMPLETE_MESSAGE) {
+ av_log(h, AV_LOG_DEBUG, "Received incomplete handshake, need more data\n");
+ read_data = 1;
+ continue;
+ }
+
+ /* remote requests a client certificate - attempt to continue without one anyway */
+ if (sspi_ret == SEC_I_INCOMPLETE_CREDENTIALS &&
+ !(c->request_flags & ISC_REQ_USE_SUPPLIED_CREDS)) {
+ av_log(h, AV_LOG_VERBOSE, "Client certificate has been requested, ignoring\n");
+ c->request_flags |= ISC_REQ_USE_SUPPLIED_CREDS;
+ read_data = 0;
+ continue;
+ }
+
+ /* continue handshake */
+ if (sspi_ret == SEC_I_CONTINUE_NEEDED || sspi_ret == SEC_E_OK) {
+ for(i = 0; i < 3; i++) {
+ if (outbuf[i].BufferType == SECBUFFER_TOKEN && outbuf[i].cbBuffer > 0) {
+ ret = ffurl_write(c->tls_shared.tcp, outbuf[i].pvBuffer, outbuf[i].cbBuffer);
+ if (ret < 0 || ret != outbuf[i].cbBuffer) {
+ av_log(h, AV_LOG_VERBOSE, "Failed to send handshake data\n");
+ ret = AVERROR(EIO);
+ goto fail;
+ }
+ }
+
+ if (outbuf[i].pvBuffer != NULL) {
+ FreeContextBuffer(outbuf[i].pvBuffer);
+ outbuf[i].pvBuffer = NULL;
+ }
+ }
+ } else {
+ if (sspi_ret == SEC_E_WRONG_PRINCIPAL)
+ av_log(h, AV_LOG_ERROR, "SNI or certificate check failed\n");
+ else
+ av_log(h, AV_LOG_ERROR, "Creating security context failed (0x%lx)\n", sspi_ret);
+ ret = AVERROR_UNKNOWN;
+ goto fail;
+ }
+
+ if (inbuf[1].BufferType == SECBUFFER_EXTRA && inbuf[1].cbBuffer > 0) {
+ if (c->enc_buf_offset > inbuf[1].cbBuffer) {
+ memmove(c->enc_buf, (c->enc_buf + c->enc_buf_offset) - inbuf[1].cbBuffer,
+ inbuf[1].cbBuffer);
+ c->enc_buf_offset = inbuf[1].cbBuffer;
+ if (sspi_ret == SEC_I_CONTINUE_NEEDED) {
+ read_data = 0;
+ continue;
+ }
+ }
+ } else {
+ c->enc_buf_offset = 0;
+ }
+
+ if (sspi_ret == SEC_I_CONTINUE_NEEDED) {
+ read_data = 1;
+ continue;
+ }
+
+ break;
+ }
+
+ return 0;
+
+fail:
+ /* free any remaining output data */
+ for(i = 0; i < 3; i++) {
+ if (outbuf[i].pvBuffer != NULL) {
+ FreeContextBuffer(outbuf[i].pvBuffer);
+ outbuf[i].pvBuffer = NULL;
+ }
+ }
+
+ return ret;
+}
+
+static int tls_client_handshake(URLContext *h)
+{
+ TLSContext *c = h->priv_data;
+ TLSShared *s = &c->tls_shared;
+ SecBuffer outbuf;
+ SecBufferDesc outbuf_desc;
+ SECURITY_STATUS sspi_ret;
+ int ret;
+
+ InitSecBuffer(&outbuf, SECBUFFER_EMPTY, NULL, 0);
+ InitSecBufferDesc(&outbuf_desc, &outbuf, 1);
+
+ c->request_flags = ISC_REQ_SEQUENCE_DETECT | ISC_REQ_REPLAY_DETECT |
+ ISC_REQ_CONFIDENTIALITY | ISC_REQ_ALLOCATE_MEMORY |
+ ISC_REQ_STREAM;
+
+ sspi_ret = InitializeSecurityContext(&c->cred_handle, NULL, s->host, c->request_flags, 0, 0,
+ NULL, 0, &c->ctxt_handle, &outbuf_desc, &c->context_flags,
+ &c->ctxt_timestamp);
+ if(sspi_ret != SEC_I_CONTINUE_NEEDED) {
+ av_log(h, AV_LOG_ERROR, "Unable to create initial security context (0x%lx)\n", sspi_ret);
+ ret = AVERROR_UNKNOWN;
+ goto fail;
+ }
+
+ ret = ffurl_write(s->tcp, outbuf.pvBuffer, outbuf.cbBuffer);
+ FreeContextBuffer(outbuf.pvBuffer);
+ if (ret < 0 || ret != outbuf.cbBuffer) {
+ av_log(h, AV_LOG_ERROR, "Failed to send initial handshake data\n");
+ ret = AVERROR(EIO);
+ goto fail;
+ }
+
+ return tls_client_handshake_loop(h, 1);
+
+fail:
+ DeleteSecurityContext(&c->ctxt_handle);
+ return ret;
+}
+
+static int tls_open(URLContext *h, const char *uri, int flags, AVDictionary **options)
+{
+ TLSContext *c = h->priv_data;
+ TLSShared *s = &c->tls_shared;
+ SECURITY_STATUS sspi_ret;
+ SCHANNEL_CRED schannel_cred;
+ int ret;
+
+ if ((ret = ff_tls_open_underlying(s, h, uri, options)) < 0)
+ goto fail;
+
+ if (s->listen) {
+ av_log(h, AV_LOG_ERROR, "TLS Listen Sockets with SChannel is not implemented.\n");
+ ret = AVERROR(EINVAL);
+ goto fail;
+ }
+
+ /* SChannel Options */
+ memset(&schannel_cred, 0, sizeof(schannel_cred));
+ schannel_cred.dwVersion = SCHANNEL_CRED_VERSION;
+
+ if (s->verify)
+ schannel_cred.dwFlags = SCH_CRED_AUTO_CRED_VALIDATION |
+ SCH_CRED_REVOCATION_CHECK_CHAIN;
+ else
+ schannel_cred.dwFlags = SCH_CRED_MANUAL_CRED_VALIDATION |
+ SCH_CRED_IGNORE_NO_REVOCATION_CHECK |
+ SCH_CRED_IGNORE_REVOCATION_OFFLINE;
+
+ /* Get credential handle */
+ sspi_ret = AcquireCredentialsHandle(NULL, (TCHAR *)UNISP_NAME, SECPKG_CRED_OUTBOUND,
+ NULL, &schannel_cred, NULL, NULL, &c->cred_handle,
+ &c->cred_timestamp);
+ if (sspi_ret != SEC_E_OK) {
+ av_log(h, AV_LOG_ERROR, "Unable to acquire security credentials (0x%lx)\n", sspi_ret);
+ ret = AVERROR_UNKNOWN;
+ goto fail;
+ }
+
+ ret = tls_client_handshake(h);
+ if (ret < 0)
+ goto fail;
+
+ c->connected = 1;
+
+ return 0;
+
+fail:
+ FreeCredentialsHandle(&c->cred_handle);
+ return ret;
+}
+
+static int tls_shutdown_client(URLContext *h)
+{
+ TLSContext *c = h->priv_data;
+ TLSShared *s = &c->tls_shared;
+ int ret;
+
+ if (c->connected) {
+ SecBufferDesc BuffDesc;
+ SecBuffer Buffer;
+ SECURITY_STATUS sspi_ret;
+ SecBuffer outbuf;
+ SecBufferDesc outbuf_desc;
+
+ DWORD dwshut = SCHANNEL_SHUTDOWN;
+ InitSecBuffer(&Buffer, SECBUFFER_TOKEN, &dwshut, sizeof(dwshut));
+ InitSecBufferDesc(&BuffDesc, &Buffer, 1);
+
+ sspi_ret = ApplyControlToken(&c->ctxt_handle, &BuffDesc);
+ if (sspi_ret != SEC_E_OK)
+ av_log(h, AV_LOG_ERROR, "ApplyControlToken failed\n");
+
+ InitSecBuffer(&outbuf, SECBUFFER_EMPTY, NULL, 0);
+ InitSecBufferDesc(&outbuf_desc, &outbuf, 1);
+
+ sspi_ret = InitializeSecurityContext(&c->cred_handle, &c->ctxt_handle, s->host,
+ c->request_flags, 0, 0, NULL, 0, &c->ctxt_handle,
+ &outbuf_desc, &c->context_flags, &c->ctxt_timestamp);
+ if (sspi_ret == SEC_E_OK || sspi_ret == SEC_I_CONTEXT_EXPIRED) {
+ ret = ffurl_write(s->tcp, outbuf.pvBuffer, outbuf.cbBuffer);
+ FreeContextBuffer(outbuf.pvBuffer);
+ if (ret < 0 || ret != outbuf.cbBuffer)
+ av_log(h, AV_LOG_ERROR, "Failed to send close message\n");
+ }
+
+ c->connected = 0;
+ }
+ return 0;
+}
+
+static int tls_close(URLContext *h)
+{
+ TLSContext *c = h->priv_data;
+
+ tls_shutdown_client(h);
+
+ DeleteSecurityContext(&c->ctxt_handle);
+ FreeCredentialsHandle(&c->cred_handle);
+
+ av_freep(&c->enc_buf);
+ av_freep(&c->dec_buf);
+
+ if (c->tls_shared.tcp)
+ ffurl_close(c->tls_shared.tcp);
+ return 0;
+}
+
+static int tls_read(URLContext *h, uint8_t *buf, int len)
+{
+ TLSContext *c = h->priv_data;
+ TLSShared *s = &c->tls_shared;
+ SECURITY_STATUS sspi_ret = SEC_E_OK;
+ SecBuffer inbuf[4];
+ SecBufferDesc inbuf_desc;
+ int size, ret;
+ int min_enc_buf_size = len + SCHANNEL_FREE_BUFFER_SIZE;
+
+ if (len && len <= c->dec_buf_offset)
+ goto cleanup;
+
+ if (c->sspi_close_notify)
+ goto cleanup;
+
+ if (!c->connection_closed) {
+ size = c->enc_buf_size - c->enc_buf_offset;
+ if (size < SCHANNEL_FREE_BUFFER_SIZE || c->enc_buf_size < min_enc_buf_size) {
+ c->enc_buf_size = c->enc_buf_offset + SCHANNEL_FREE_BUFFER_SIZE;
+ if (c->enc_buf_size < min_enc_buf_size)
+ c->enc_buf_size = min_enc_buf_size;
+ ret = av_reallocp(&c->enc_buf, c->enc_buf_size);
+ if (ret < 0)
+ goto fail;
+ }
+
+ ret = ffurl_read(s->tcp, c->enc_buf + c->enc_buf_offset,
+ c->enc_buf_size - c->enc_buf_offset);
+ if (ret < 0) {
+ av_log(h, AV_LOG_ERROR, "Unable to read from socket\n");
+ goto fail;
+ } else if (ret == 0)
+ c->connection_closed = 1;
+
+ c->enc_buf_offset += ret;
+ }
+
+ while (c->enc_buf_offset > 0 && sspi_ret == SEC_E_OK &&
+ (!len || c->dec_buf_offset < len || c->connection_closed)) {
+ /* input buffer */
+ InitSecBuffer(&inbuf[0], SECBUFFER_DATA, c->enc_buf, c->enc_buf_offset);
+
+ /* additional buffers for possible output */
+ InitSecBuffer(&inbuf[1], SECBUFFER_EMPTY, NULL, 0);
+ InitSecBuffer(&inbuf[2], SECBUFFER_EMPTY, NULL, 0);
+ InitSecBuffer(&inbuf[3], SECBUFFER_EMPTY, NULL, 0);
+ InitSecBufferDesc(&inbuf_desc, inbuf, 4);
+
+ sspi_ret = DecryptMessage(&c->ctxt_handle, &inbuf_desc, 0, NULL);
+ if (sspi_ret == SEC_E_OK || sspi_ret == SEC_I_RENEGOTIATE ||
+ sspi_ret == SEC_I_CONTEXT_EXPIRED) {
+ /* handle decrypted data */
+ if (inbuf[1].BufferType == SECBUFFER_DATA) {
+ /* grow buffer if needed */
+ size = inbuf[1].cbBuffer > SCHANNEL_FREE_BUFFER_SIZE ?
+ inbuf[1].cbBuffer : SCHANNEL_FREE_BUFFER_SIZE;
+ if (c->dec_buf_size - c->dec_buf_offset < size || c->dec_buf_size < len) {
+ c->dec_buf_size = c->dec_buf_offset + size;
+ if (c->dec_buf_size < len)
+ c->dec_buf_size = len;
+ ret = av_reallocp(&c->dec_buf, c->dec_buf_size);
+ if (ret < 0)
+ goto fail;
+ }
+
+ /* copy decrypted data to buffer */
+ size = inbuf[1].cbBuffer;
+ if (size) {
+ memcpy(c->dec_buf + c->dec_buf_offset, inbuf[1].pvBuffer, size);
+ c->dec_buf_offset += size;
+ }
+ }
+ if (inbuf[3].BufferType == SECBUFFER_EXTRA && inbuf[3].cbBuffer > 0) {
+ if (c->enc_buf_offset > inbuf[3].cbBuffer) {
+ memmove(c->enc_buf, (c->enc_buf + c->enc_buf_offset) - inbuf[3].cbBuffer,
+ inbuf[3].cbBuffer);
+ c->enc_buf_offset = inbuf[3].cbBuffer;
+ }
+ } else
+ c->enc_buf_offset = 0;
+
+ if (sspi_ret == SEC_I_RENEGOTIATE) {
+ if (c->enc_buf_offset) {
+ av_log(h, AV_LOG_ERROR, "Cannot renegotiate, encrypted data buffer not empty\n");
+ ret = AVERROR_UNKNOWN;
+ goto cleanup;
+ }
+
+ av_log(h, AV_LOG_VERBOSE, "Re-negotiating security context\n");
+ ret = tls_client_handshake_loop(h, 0);
+ if (ret < 0) {
+ goto cleanup;
+ }
+ sspi_ret = SEC_E_OK;
+ continue;
+ } else if (sspi_ret == SEC_I_CONTEXT_EXPIRED) {
+ c->sspi_close_notify = 1;
+ if (!c->connection_closed) {
+ c->connection_closed = 1;
+ av_log(h, AV_LOG_VERBOSE, "Server closed the connection\n");
+ }
+ ret = 0;
+ goto cleanup;
+ }
+ } else if (sspi_ret == SEC_E_INCOMPLETE_MESSAGE) {
+ ret = AVERROR(EAGAIN);
+ goto cleanup;
+ } else {
+ av_log(h, AV_LOG_ERROR, "Unable to decrypt message\n");
+ ret = AVERROR(EIO);
+ goto cleanup;
+ }
+ }
+
+ ret = 0;
+
+cleanup:
+ size = len < c->dec_buf_offset ? len : c->dec_buf_offset;
+ if (size) {
+ memcpy(buf, c->dec_buf, size);
+ memmove(c->dec_buf, c->dec_buf + size, c->dec_buf_offset - size);
+ c->dec_buf_offset -= size;
+
+ return size;
+ }
+
+ if (ret == 0 && !c->connection_closed)
+ ret = AVERROR(EAGAIN);
+
+ return ret < 0 ? ret : 0;
+
+fail:
+ return ret;
+}
+
+static int tls_write(URLContext *h, const uint8_t *buf, int len)
+{
+ TLSContext *c = h->priv_data;
+ TLSShared *s = &c->tls_shared;
+ SECURITY_STATUS sspi_ret;
+ int ret, data_size;
+ uint8_t *data = NULL;
+ SecBuffer outbuf[4];
+ SecBufferDesc outbuf_desc;
+
+ if (c->Sizes.cbMaximumMessage == 0) {
+ sspi_ret = QueryContextAttributes(&c->ctxt_handle, SECPKG_ATTR_STREAM_SIZES, &c->Sizes);
+ if (sspi_ret != SEC_E_OK)
+ return AVERROR_UNKNOWN;
+ }
+
+ if (len > c->Sizes.cbMaximumMessage) {
+ av_log(h, AV_LOG_ERROR, "Message exceeds max message size\n");
+ return AVERROR(EIO);
+ }
+
+ data_size = c->Sizes.cbHeader + len + c->Sizes.cbTrailer;
+ data = av_malloc(data_size);
+ if (data == NULL)
+ return AVERROR(ENOMEM);
+
+ InitSecBuffer(&outbuf[0], SECBUFFER_STREAM_HEADER,
+ data, c->Sizes.cbHeader);
+ InitSecBuffer(&outbuf[1], SECBUFFER_DATA,
+ data + c->Sizes.cbHeader, len);
+ InitSecBuffer(&outbuf[2], SECBUFFER_STREAM_TRAILER,
+ data + c->Sizes.cbHeader + len,
+ c->Sizes.cbTrailer);
+ InitSecBuffer(&outbuf[3], SECBUFFER_EMPTY, NULL, 0);
+ InitSecBufferDesc(&outbuf_desc, outbuf, 4);
+
+ memcpy(outbuf[1].pvBuffer, buf, len);
+
+ sspi_ret = EncryptMessage(&c->ctxt_handle, 0, &outbuf_desc, 0);
+ if (sspi_ret == SEC_E_OK) {
+ len = outbuf[0].cbBuffer + outbuf[1].cbBuffer + outbuf[2].cbBuffer;
+ ret = ffurl_write(s->tcp, data, len);
+ if (ret < 0 || ret != len) {
+ ret = AVERROR(EIO);
+ av_log(h, AV_LOG_ERROR, "Writing encrypted data to socket failed\n");
+ goto fail;
+ }
+ } else {
+ av_log(h, AV_LOG_ERROR, "Encrypting data failed\n");
+ if (sspi_ret == SEC_E_INSUFFICIENT_MEMORY)
+ ret = AVERROR(ENOMEM);
+ else
+ ret = AVERROR(EIO);
+ goto fail;
+ }
+
+ av_freep(&data);
+ return outbuf[1].cbBuffer;
+
+fail:
+ av_freep(&data);
+ return ret;
+}
+
+static const AVOption options[] = {
+ TLS_COMMON_OPTIONS(TLSContext, tls_shared),
+ { NULL }
+};
+
+static const AVClass tls_class = {
+ .class_name = "tls",
+ .item_name = av_default_item_name,
+ .option = options,
+ .version = LIBAVUTIL_VERSION_INT,
+};
+
+URLProtocol ff_tls_schannel_protocol = {
+ .name = "tls",
+ .url_open2 = tls_open,
+ .url_read = tls_read,
+ .url_write = tls_write,
+ .url_close = tls_close,
+ .priv_data_size = sizeof(TLSContext),
+ .flags = URL_PROTOCOL_FLAG_NETWORK,
+ .priv_data_class = &tls_class,
+};
--
2.6.2.windows.1
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