in src/protocols/rdp/channels/rdpsnd/rdpsnd-messages.c [33:227]
void guac_rdpsnd_formats_handler(guac_rdp_common_svc* svc,
wStream* input_stream, guac_rdpsnd_pdu_header* header) {
int server_format_count;
int server_version;
int i;
wStream* output_stream;
int output_body_size;
unsigned char* output_stream_end;
guac_client* client = svc->client;
guac_rdpsnd* rdpsnd = (guac_rdpsnd*) svc->data;
guac_rdp_client* rdp_client = (guac_rdp_client*) client->data;
guac_audio_stream* audio = rdp_client->audio;
/* 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);
Stream_Seek_UINT8(input_stream);
Stream_Read_UINT16(input_stream, server_version);
Stream_Seek_UINT8(input_stream);
/* Initialize Client Audio Formats and Version PDU */
output_stream = Stream_New(NULL, 24);
Stream_Write_UINT8(output_stream, SNDC_FORMATS);
Stream_Write_UINT8(output_stream, 0);
/* Fill in body size later */
Stream_Seek_UINT16(output_stream); /* offset = 0x02 */
/* Flags, volume, and pitch */
Stream_Write_UINT32(output_stream, TSSNDCAPS_ALIVE);
Stream_Write_UINT32(output_stream, 0);
Stream_Write_UINT32(output_stream, 0);
/* Datagram port (UDP) */
Stream_Write_UINT16(output_stream, 0);
/* Fill in format count later */
Stream_Seek_UINT16(output_stream); /* offset = 0x12 */
/* Version and padding */
Stream_Write_UINT8(output_stream, 0);
Stream_Write_UINT16(output_stream, 6);
Stream_Write_UINT8(output_stream, 0);
/* Check each server format, respond if supported and audio is enabled */
if (audio != NULL) {
for (i=0; i < server_format_count; i++) {
unsigned char* format_start;
int format_tag;
int channels;
int rate;
int bps;
int body_size;
/* 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);
Stream_Read_UINT32(input_stream, rate);
Stream_Seek_UINT32(input_stream);
Stream_Seek_UINT16(input_stream);
Stream_Read_UINT16(input_stream, bps);
/* 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 */
if (format_tag == WAVE_FORMAT_PCM) {
/* If can fit another format, accept it */
if (rdpsnd->format_count < GUAC_RDP_MAX_FORMATS) {
/* Add channel */
int current = rdpsnd->format_count++;
rdpsnd->formats[current].rate = rate;
rdpsnd->formats[current].channels = channels;
rdpsnd->formats[current].bps = bps;
/* Log format */
guac_client_log(client, GUAC_LOG_INFO,
"Accepted format: %i-bit PCM with %i channels at "
"%i Hz",
bps, channels, rate);
/* Ensure audio stream is configured to use accepted
* format */
guac_audio_stream_reset(audio, NULL, rate, channels, bps);
/* Queue format for sending as accepted */
Stream_EnsureRemainingCapacity(output_stream,
18 + body_size);
Stream_Write(output_stream, format_start, 18 + body_size);
/*
* BEWARE that using Stream_EnsureRemainingCapacity means
* that any pointers returned via Stream_GetPointer on
* output_stream are invalid.
*/
}
/* Otherwise, log that we dropped one */
else
guac_client_log(client, GUAC_LOG_INFO,
"Dropped valid format: %i-bit PCM with %i "
"channels at %i Hz",
bps, channels, rate);
}
}
}
/* Otherwise, ignore all supported formats as we do not intend to actually
* receive audio */
else
guac_client_log(client, GUAC_LOG_DEBUG,
"Audio explicitly disabled. Ignoring supported formats.");
/* Calculate size of PDU */
output_body_size = Stream_GetPosition(output_stream) - 4;
Stream_GetPointer(output_stream, output_stream_end);
/* Set body size */
Stream_SetPosition(output_stream, 0x02);
Stream_Write_UINT16(output_stream, output_body_size);
/* Set format count */
Stream_SetPosition(output_stream, 0x12);
Stream_Write_UINT16(output_stream, rdpsnd->format_count);
/* Reposition cursor at end (necessary for message send) */
Stream_SetPosition(output_stream, output_stream_end - Stream_Buffer(output_stream));
/* Send accepted formats */
guac_rdp_common_svc_write(svc, output_stream);
/* If version greater than 6, must send Quality Mode PDU */
if (server_version >= 6) {
/* Always send High Quality for now */
output_stream = Stream_New(NULL, 8);
Stream_Write_UINT8(output_stream, SNDC_QUALITYMODE);
Stream_Write_UINT8(output_stream, 0);
Stream_Write_UINT16(output_stream, 4);
Stream_Write_UINT16(output_stream, HIGH_QUALITY);
Stream_Write_UINT16(output_stream, 0);
guac_rdp_common_svc_write(svc, output_stream);
}
}