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GUACAMOLE-1059: Merge changes leveraging appropriate FreeRDP checks to verify input stream length.

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This commit is contained in:
Mike Jumper 2020-05-07 14:09:47 -07:00 committed by GitHub
commit 0bf65ce8b0
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GPG Key ID: 4AEE18F83AFDEB23
10 changed files with 320 additions and 7 deletions
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35
src/protocols/rdp/channels/rdpdr/rdpdr-fs-messages-file-info.c
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@ -135,11 +135,28 @@ void guac_rdpdr_fs_process_set_rename_info(guac_rdp_common_svc* svc,
wStream* output_stream;
char destination_path[GUAC_RDP_FS_MAX_PATH];
/* Check stream size prior to reading. */
if (Stream_GetRemainingLength(input_stream) < 6) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Set "
"Information Request (FileRenameInformation) PDU does not "
"contain the expected number of bytes. File redirection "
"may not work as expected.");
return;
}
/* Read structure */
Stream_Seek_UINT8(input_stream); /* ReplaceIfExists */
Stream_Seek_UINT8(input_stream); /* RootDirectory */
Stream_Read_UINT32(input_stream, filename_length); /* FileNameLength */
if (Stream_GetRemainingLength(input_stream) < filename_length) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Set "
"Information Request (FileRenameInformation) PDU does not "
"contain the expected number of bytes. File redirection "
"may not work as expected.");
return;
}
/* Convert name to UTF-8 */
guac_rdp_utf16_to_utf8(Stream_Pointer(input_stream), filename_length/2,
destination_path, sizeof(destination_path));
@ -192,6 +209,15 @@ void guac_rdpdr_fs_process_set_allocation_info(guac_rdp_common_svc* svc,
UINT64 size;
wStream* output_stream;
/* Check to make sure the stream has at least 8 bytes (UINT64) */
if (Stream_GetRemainingLength(input_stream) < 8) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Set "
"Information Request (FileAllocationInformation) PDU does not "
"contain the expected number of bytes. File redirection "
"may not work as expected.");
return;
}
/* Read new size */
Stream_Read_UINT64(input_stream, size); /* AllocationSize */
@ -244,6 +270,15 @@ void guac_rdpdr_fs_process_set_end_of_file_info(guac_rdp_common_svc* svc,
UINT64 size;
wStream* output_stream;
/* Check to make sure stream contains at least 8 bytes (UINT64) */
if (Stream_GetRemainingLength(input_stream) < 8) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Set "
"Information Request (FileEndOfFileInformation) PDU does not "
"contain the expected number of bytes. File redirection "
"may not work as expected.");
return;
}
/* Read new size */
Stream_Read_UINT64(input_stream, size); /* AllocationSize */

84
src/protocols/rdp/channels/rdpdr/rdpdr-fs-messages.c
View File

@ -48,6 +48,14 @@ void guac_rdpdr_fs_process_create(guac_rdp_common_svc* svc,
int create_disposition, create_options, path_length;
char path[GUAC_RDP_FS_MAX_PATH];
/* Check remaining stream data prior to reading. */
if (Stream_GetRemainingLength(input_stream) < 32) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Create Drive "
"Request PDU does not contain the expected number of bytes. "
"Drive redirection may not work as expected.");
return;
}
/* Read "create" information */
Stream_Read_UINT32(input_stream, desired_access);
Stream_Seek_UINT64(input_stream); /* allocation size */
@ -57,6 +65,14 @@ void guac_rdpdr_fs_process_create(guac_rdp_common_svc* svc,
Stream_Read_UINT32(input_stream, create_options);
Stream_Read_UINT32(input_stream, path_length);
/* Check to make sure the stream contains path_length bytes. */
if(Stream_GetRemainingLength(input_stream) < path_length) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Create Drive "
"Request PDU does not contain the expected number of bytes. "
"Drive redirection may not work as expected.");
return;
}
/* Convert path to UTF-8 */
guac_rdp_utf16_to_utf8(Stream_Pointer(input_stream), path_length/2 - 1,
path, sizeof(path));
@ -123,6 +139,14 @@ void guac_rdpdr_fs_process_read(guac_rdp_common_svc* svc,
wStream* output_stream;
/* Check remaining bytes before reading stream. */
if (Stream_GetRemainingLength(input_stream) < 12) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Read "
"Request PDU does not contain the expected number of bytes. "
"Drive redirection may not work as expected.");
return;
}
/* Read packet */
Stream_Read_UINT32(input_stream, length);
Stream_Read_UINT64(input_stream, offset);
@ -172,6 +196,14 @@ void guac_rdpdr_fs_process_write(guac_rdp_common_svc* svc,
wStream* output_stream;
/* Check remaining length. */
if (Stream_GetRemainingLength(input_stream) < 32) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Write "
"Request PDU does not contain the expected number of bytes. "
"Drive redirection may not work as expected.");
return;
}
/* Read packet */
Stream_Read_UINT32(input_stream, length);
Stream_Read_UINT64(input_stream, offset);
@ -181,6 +213,14 @@ void guac_rdpdr_fs_process_write(guac_rdp_common_svc* svc,
"%s: [file_id=%i] length=%i, offset=%" PRIu64,
__func__, iorequest->file_id, length, (uint64_t) offset);
/* Check to make sure stream contains at least length bytes */
if (Stream_GetRemainingLength(input_stream) < length) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Write "
"Request PDU does not contain the expected number of bytes. "
"Drive redirection may not work as expected.");
return;
}
/* Attempt write */
bytes_written = guac_rdp_fs_write((guac_rdp_fs*) device->data,
iorequest->file_id, offset, Stream_Pointer(input_stream), length);
@ -244,6 +284,14 @@ void guac_rdpdr_fs_process_volume_info(guac_rdp_common_svc* svc,
int fs_information_class;
/* Check remaining length */
if (Stream_GetRemainingLength(input_stream) < 4) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Query "
"Volume Information PDU does not contain the expected number "
"of bytes. Drive redirection may not work as expected.");
return;
}
Stream_Read_UINT32(input_stream, fs_information_class);
/* Dispatch to appropriate class-specific handler */
@ -282,6 +330,14 @@ void guac_rdpdr_fs_process_file_info(guac_rdp_common_svc* svc,
int fs_information_class;
/* Check remaining length */
if (Stream_GetRemainingLength(input_stream) < 4) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Query "
"Information PDU does not contain the expected number of "
"bytes. Drive redirection may not work as expected.");
return;
}
Stream_Read_UINT32(input_stream, fs_information_class);
/* Dispatch to appropriate class-specific handler */
@ -328,6 +384,14 @@ void guac_rdpdr_fs_process_set_file_info(guac_rdp_common_svc* svc,
int fs_information_class;
int length;
/* Check remaining length */
if (Stream_GetRemainingLength(input_stream) < 32) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Set "
"Information PDU does not contain the expected number of "
"bytes. Drive redirection may not work as expected.");
return;
}
Stream_Read_UINT32(input_stream, fs_information_class);
Stream_Read_UINT32(input_stream, length); /* Length */
Stream_Seek(input_stream, 24); /* Padding */
@ -406,6 +470,13 @@ void guac_rdpdr_fs_process_query_directory(guac_rdp_common_svc* svc,
if (file == NULL)
return;
if (Stream_GetRemainingLength(input_stream) < 9) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Query "
"Directory PDU does not contain the expected number of bytes. "
"Drive redirection may not work as expected.");
return;
}
/* Read main header */
Stream_Read_UINT32(input_stream, fs_information_class);
Stream_Read_UINT8(input_stream, initial_query);
@ -414,8 +485,19 @@ void guac_rdpdr_fs_process_query_directory(guac_rdp_common_svc* svc,
/* If this is the first query, the path is included after padding */
if (initial_query) {
/*
* Check to make sure Stream has at least the 23 padding bytes in it
* prior to seeking.
*/
if (Stream_GetRemainingLength(input_stream) < (23 + path_length)) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Drive Query "
"Directory PDU does not contain the expected number of "
"bytes. Drive redirection may not work as expected.");
return;
}
Stream_Seek(input_stream, 23); /* Padding */
/* Convert path to UTF-8 */
guac_rdp_utf16_to_utf8(Stream_Pointer(input_stream), path_length/2 - 1,
file->dir_pattern, sizeof(file->dir_pattern));

50
src/protocols/rdp/channels/rdpdr/rdpdr-messages.c
View File

@ -212,6 +212,14 @@ void guac_rdpdr_process_server_announce(guac_rdp_common_svc* svc,
unsigned int major, minor, client_id;
/* Stream should contain at least 8 bytes (UINT16 + UINT16 + UINT32) */
if (Stream_GetRemainingLength(input_stream) < 8) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Announce "
"Request PDU does not contain the expected number of bytes. "
"Device redirection may not work as expected.");
return;
}
Stream_Read_UINT16(input_stream, major);
Stream_Read_UINT16(input_stream, minor);
Stream_Read_UINT32(input_stream, client_id);
@ -243,6 +251,14 @@ void guac_rdpdr_process_device_reply(guac_rdp_common_svc* svc,
unsigned int device_id, ntstatus;
int severity, c, n, facility, code;
/* Stream should contain at least 8 bytes (UINT32 + UINT32 ) */
if (Stream_GetRemainingLength(input_stream) < 8) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Device Announce"
"Response PDU does not contain the expected number of bytes."
"Device redirection may not work as expected.");
return;
}
Stream_Read_UINT32(input_stream, device_id);
Stream_Read_UINT32(input_stream, ntstatus);
@ -278,6 +294,14 @@ void guac_rdpdr_process_device_iorequest(guac_rdp_common_svc* svc,
guac_rdpdr* rdpdr = (guac_rdpdr*) svc->data;
guac_rdpdr_iorequest iorequest;
/* Check to make sure the Stream contains at least 20 bytes (5 x UINT32 ). */
if (Stream_GetRemainingLength(input_stream) < 20) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Device I/O Request PDU "
"does not contain the expected number of bytes. Device "
"redirection may not work as expected.");
return;
}
/* Read header */
Stream_Read_UINT32(input_stream, iorequest.device_id);
Stream_Read_UINT32(input_stream, iorequest.file_id);
@ -306,6 +330,14 @@ void guac_rdpdr_process_server_capability(guac_rdp_common_svc* svc,
int count;
int i;
/* Check to make sure the Stream has at least 4 bytes (UINT16 + 2) */
if (Stream_GetRemainingLength(input_stream) < 4) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Core Capability "
"Request PDU does not contain the expected number of bytes."
"Device redirection may not work as expected.");
return;
}
/* Read header */
Stream_Read_UINT16(input_stream, count);
Stream_Seek(input_stream, 2);
@ -316,9 +348,27 @@ void guac_rdpdr_process_server_capability(guac_rdp_common_svc* svc,
int type;
int length;
/* Make sure Stream has at least 4 bytes (UINT16 + UINT16) */
if (Stream_GetRemainingLength(input_stream) < 4) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Core "
"Capability Request PDU does not contain the expected "
"number of bytes. Device redirection may not work as "
"expected.");
break;
}
Stream_Read_UINT16(input_stream, type);
Stream_Read_UINT16(input_stream, length);
/* Make sure Stream has required length remaining for Seek below. */
if (Stream_GetRemainingLength(input_stream) < (length - 4)) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Server Core "
"Capability Request PDU does not contain the expected "
"number of bytes. Device redirection may not work as "
"expected.");
break;
}
/* Ignore all for now */
guac_client_log(svc->client, GUAC_LOG_DEBUG, "Ignoring server capability set type=0x%04x, length=%i", type, length);
Stream_Seek(input_stream, length - 4);

16
src/protocols/rdp/channels/rdpdr/rdpdr-printer.c
View File

@ -67,12 +67,28 @@ void guac_rdpdr_process_print_job_write(guac_rdp_common_svc* svc,
int length;
int status;
/* Verify that Stream contains at least 32 bytes (UINT32 + 8 + 20) */
if (Stream_GetRemainingLength(input_stream) < 32) {
guac_client_log(client, GUAC_LOG_WARNING, "Print job write stream does "
"not contain the expected number of bytes. Printer redirection "
"may not work as expected.");
return;
}
/* Read buffer of print data */
Stream_Read_UINT32(input_stream, length);
Stream_Seek(input_stream, 8); /* Offset */
Stream_Seek(input_stream, 20); /* Padding */
buffer = Stream_Pointer(input_stream);
/* Verify the stream has at least length number of bytes remaining. */
if (Stream_GetRemainingLength(input_stream) < length) {
guac_client_log(client, GUAC_LOG_WARNING, "Print job write stream does "
"not contain the expected number of bytes. Printer redirection "
"may not work as expected.");
return;
}
/* Write data only if job exists, translating status for RDP */
if (job != NULL && (length = guac_rdp_print_job_write(job,
buffer, length)) >= 0) {

11
src/protocols/rdp/channels/rdpdr/rdpdr.c
View File

@ -38,6 +38,17 @@ void guac_rdpdr_process_receive(guac_rdp_common_svc* svc,
int component;
int packet_id;
/*
* Check that device redirection stream contains at least 4 bytes
* (UINT16 + UINT16).
*/
if (Stream_GetRemainingLength(input_stream) < 4) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Device redirection "
"channel PDU header does not contain the expected number of "
"bytes. Device redirection may not function as expected.");
return;
}
/* Read header */
Stream_Read_UINT16(input_stream, component);
Stream_Read_UINT16(input_stream, packet_id);

54
src/protocols/rdp/channels/rdpsnd/rdpsnd-messages.c
View File

@ -50,6 +50,17 @@ void guac_rdpsnd_formats_handler(guac_rdp_common_svc* svc,
/* Reset own format count */
rdpsnd->format_count = 0;
/*
* Check to make sure the stream has at least 20 bytes (14 byte seek,
* 2 x UTF16 reads, and 2 x UTF8 seeks).
*/
if (Stream_GetRemainingLength(input_stream) < 20) {
guac_client_log(client, GUAC_LOG_WARNING, "Server Audio Formats and "
"Version PDU does not contain the expected number of bytes. "
"Audio redirection may not work as expected.");
return;
}
/* Format header */
Stream_Seek(input_stream, 14);
Stream_Read_UINT16(input_stream, server_format_count);
@ -96,6 +107,15 @@ void guac_rdpsnd_formats_handler(guac_rdp_common_svc* svc,
/* Remember position in stream */
Stream_GetPointer(input_stream, format_start);
/* Check to make sure Stream has at least 18 bytes. */
if (Stream_GetRemainingLength(input_stream) < 18) {
guac_client_log(client, GUAC_LOG_WARNING, "Server Audio "
"Formats and Version PDU does not contain the expected "
"number of bytes. Audio redirection may not work as "
"expected.");
return;
}
/* Read format */
Stream_Read_UINT16(input_stream, format_tag);
Stream_Read_UINT16(input_stream, channels);
@ -106,6 +126,16 @@ void guac_rdpsnd_formats_handler(guac_rdp_common_svc* svc,
/* Skip past extra data */
Stream_Read_UINT16(input_stream, body_size);
/* Check that Stream has at least body_size bytes remaining. */
if (Stream_GetRemainingLength(input_stream) < body_size) {
guac_client_log(client, GUAC_LOG_WARNING, "Server Audio "
"Formats and Version PDU does not contain the expected "
"number of bytes. Audio redirection may not work as "
"expected.");
return;
}
Stream_Seek(input_stream, body_size);
/* If PCM, accept */
@ -205,6 +235,14 @@ void guac_rdpsnd_training_handler(guac_rdp_common_svc* svc,
guac_rdpsnd* rdpsnd = (guac_rdpsnd*) svc->data;
/* Check to make sure audio stream contains a minimum number of bytes. */
if (Stream_GetRemainingLength(input_stream) < 4) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Audio Training PDU "
"does not contain the expected number of bytes. Audio "
"redirection may not work as expected.");
return;
}
/* Read timestamp and data size */
Stream_Read_UINT16(input_stream, rdpsnd->server_timestamp);
Stream_Read_UINT16(input_stream, data_size);
@ -232,6 +270,14 @@ void guac_rdpsnd_wave_info_handler(guac_rdp_common_svc* svc,
guac_rdp_client* rdp_client = (guac_rdp_client*) client->data;
guac_audio_stream* audio = rdp_client->audio;
/* Check to make sure audio stream contains a minimum number of bytes. */
if (Stream_GetRemainingLength(input_stream) < 12) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Audio WaveInfo PDU "
"does not contain the expected number of bytes. Sound may not "
"work as expected.");
return;
}
/* Read wave information */
Stream_Read_UINT16(input_stream, rdpsnd->server_timestamp);
Stream_Read_UINT16(input_stream, format);
@ -266,6 +312,14 @@ void guac_rdpsnd_wave_handler(guac_rdp_common_svc* svc,
guac_rdp_client* rdp_client = (guac_rdp_client*) client->data;
guac_audio_stream* audio = rdp_client->audio;
/* Verify that the stream has bytes to cover the wave size plus header. */
if (Stream_Length(input_stream) < (rdpsnd->incoming_wave_size + 4)) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Audio Wave PDU does "
"not contain the expected number of bytes. Sound may not work "
"as expected.");
return;
}
/* Wave Confirmation PDU */
wStream* output_stream = Stream_New(NULL, 8);

10
src/protocols/rdp/channels/rdpsnd/rdpsnd.c
View File

@ -35,11 +35,19 @@ void guac_rdpsnd_process_receive(guac_rdp_common_svc* svc,
guac_rdpsnd* rdpsnd = (guac_rdpsnd*) svc->data;
guac_rdpsnd_pdu_header header;
/* Check that we have at least the 4 byte header (UINT8 + UINT8 + UINT16) */
if (Stream_GetRemainingLength(input_stream) < 4) {
guac_client_log(svc->client, GUAC_LOG_WARNING, "Audio Stream does not "
"contain the expected number of bytes. Audio redirection may "
"not work as expected.");
return;
}
/* Read RDPSND PDU header */
Stream_Read_UINT8(input_stream, header.message_type);
Stream_Seek_UINT8(input_stream);
Stream_Read_UINT16(input_stream, header.body_size);
/*
* If next PDU is SNDWAVE (due to receiving WaveInfo PDU previously),
* ignore the header and parse as a Wave PDU.

5
src/protocols/rdp/plugins/guac-common-svc/guac-common-svc.c
View File

@ -116,6 +116,10 @@ static VOID guac_rdp_common_svc_handle_open_event(LPVOID user_param,
svc->_input_stream = Stream_New(NULL, total_length);
}
/* leave if we don't have a stream. */
if (svc->_input_stream == NULL)
return;
/* Add chunk to buffer only if sufficient space remains */
if (Stream_EnsureRemainingCapacity(svc->_input_stream, data_length))
Stream_Write(svc->_input_stream, data, data_length);
@ -137,6 +141,7 @@ static VOID guac_rdp_common_svc_handle_open_event(LPVOID user_param,
svc->_receive_handler(svc, svc->_input_stream);
Stream_Free(svc->_input_stream, TRUE);
svc->_input_stream = NULL;
}

52
src/protocols/rdp/plugins/guacai/guacai-messages.c
View File

@ -35,10 +35,17 @@
*
* @param format
* The structure to populate with data from the stream.
*
* @return
* Zero on success or non-zero if an error occurs processing the format.
*/
static void guac_rdp_ai_read_format(wStream* stream,
static int guac_rdp_ai_read_format(wStream* stream,
guac_rdp_ai_format* format) {
/* Check that we have at least 18 bytes (5 x UINT16, 2 x UINT32) */
if (Stream_GetRemainingLength(stream) < 18)
return 1;
/* Read audio format into structure */
Stream_Read_UINT16(stream, format->tag); /* wFormatTag */
Stream_Read_UINT16(stream, format->channels); /* nChannels */
@ -48,11 +55,19 @@ static void guac_rdp_ai_read_format(wStream* stream,
Stream_Read_UINT16(stream, format->bps); /* wBitsPerSample */
Stream_Read_UINT16(stream, format->data_size); /* cbSize */
/* Read arbitrary data block (if applicable) */
/* Read arbitrary data block (if applicable) and data is available. */
if (format->data_size != 0) {
/* Check to make sure Stream contains expected bytes. */
if (Stream_GetRemainingLength(stream) < format->data_size)
return 1;
format->data = Stream_Pointer(stream); /* data */
Stream_Seek(stream, format->data_size);
}
return 0;
}
@ -232,6 +247,14 @@ static void guac_rdp_ai_send_formatchange(IWTSVirtualChannel* channel,
void guac_rdp_ai_process_version(guac_client* client,
IWTSVirtualChannel* channel, wStream* stream) {
/* Verify we have at least 4 bytes available (UINT32) */
if (Stream_GetRemainingLength(stream) < 4) {
guac_client_log(client, GUAC_LOG_WARNING, "Audio input Versoin PDU "
"does not contain the expected number of bytes. Audio input "
"redirection may not work as expected.");
return;
}
UINT32 version;
Stream_Read_UINT32(stream, version);
@ -258,15 +281,28 @@ void guac_rdp_ai_process_formats(guac_client* client,
guac_rdp_client* rdp_client = (guac_rdp_client*) client->data;
guac_rdp_audio_buffer* audio_buffer = rdp_client->audio_input;
/* Verify we have at least 8 bytes available (2 x UINT32) */
if (Stream_GetRemainingLength(stream) < 8) {
guac_client_log(client, GUAC_LOG_WARNING, "Audio input Sound Formats "
"PDU does not contain the expected number of bytes. Audio "
"input redirection may not work as expected.");
return;
}
UINT32 num_formats;
Stream_Read_UINT32(stream, num_formats); /* NumFormats */
Stream_Seek_UINT32(stream); /* cbSizeFormatsPacket (MUST BE IGNORED) */
UINT32 index;
for (index = 0; index < num_formats; index++) {
guac_rdp_ai_format format;
guac_rdp_ai_read_format(stream, &format);
if (guac_rdp_ai_read_format(stream, &format)) {
guac_client_log(client, GUAC_LOG_WARNING, "Error occurred "
"processing audio input formats. Audio input redirection "
"may not work as expected.");
return;
}
/* Ignore anything but WAVE_FORMAT_PCM */
if (format.tag != GUAC_RDP_WAVE_FORMAT_PCM)
@ -306,6 +342,14 @@ void guac_rdp_ai_process_open(guac_client* client,
guac_rdp_client* rdp_client = (guac_rdp_client*) client->data;
guac_rdp_audio_buffer* audio_buffer = rdp_client->audio_input;
/* Verify we have at least 8 bytes available (2 x UINT32) */
if (Stream_GetRemainingLength(stream) < 8) {
guac_client_log(client, GUAC_LOG_WARNING, "Audio input Open PDU does "
"not contain the expected number of bytes. Audio input "
"redirection may not work as expected.");
return;
}
UINT32 packet_frames;
UINT32 initial_format;

10
src/protocols/rdp/plugins/guacai/guacai.c
View File

@ -52,10 +52,18 @@
static void guac_rdp_ai_handle_data(guac_client* client,
IWTSVirtualChannel* channel, wStream* stream) {
/* Verify we have at least 1 byte in the stream (UINT8) */
if (Stream_GetRemainingLength(stream) < 1) {
guac_client_log(client, GUAC_LOG_WARNING, "Audio input PDU header does "
"not contain the expected number of bytes. Audio input "
"redirection may not work as expected.");
return;
}
/* Read message ID from received PDU */
BYTE message_id;
Stream_Read_UINT8(stream, message_id);
/* Invoke appropriate message processor based on ID */
switch (message_id) {