guacamole-spice-protocol/src/protocols/rdp/guac_rdpsnd/rdpsnd_messages.c

/*
 * Copyright (C) 2013 Glyptodon LLC
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */


#include <pthread.h>
#include <stdlib.h>
#include <string.h>
#include <freerdp/constants.h>
#include <freerdp/utils/svc_plugin.h>

#ifdef ENABLE_WINPR
#include <winpr/stream.h>
#include <winpr/wtypes.h>
#else
#include "compat/winpr-stream.h"
#include "compat/winpr-wtypes.h"
#endif

#include <guacamole/audio.h>
#include <guacamole/client.h>

#include "rdpsnd_service.h"
#include "rdpsnd_messages.h"
#include "client.h"

/* MESSAGE HANDLERS */

void guac_rdpsnd_formats_handler(guac_rdpsndPlugin* rdpsnd,
        guac_audio_stream* audio, 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;

    rdp_guac_client_data* guac_client_data =
        (rdp_guac_client_data*) audio->client->data;

    /* 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 */
    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);

        /* 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);
        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_info(audio->client,
                        "Accepted format: %i-bit PCM with %i channels at "
                        "%i Hz",
                        bps, channels, rate);

                /* 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_info(audio->client,
                        "Dropped valid format: %i-bit PCM with %i channels at "
                        "%i Hz",
                        bps, channels, rate);

        }

    }

    /* 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_SetPointer(output_stream, output_stream_end);

    /* Send accepted formats */
    pthread_mutex_lock(&(guac_client_data->rdp_lock));
    svc_plugin_send((rdpSvcPlugin*)rdpsnd, 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);

        svc_plugin_send((rdpSvcPlugin*)rdpsnd, output_stream);
    }

    pthread_mutex_unlock(&(guac_client_data->rdp_lock));

}

/* server is getting a feel of the round trip time */
void guac_rdpsnd_training_handler(guac_rdpsndPlugin* rdpsnd,
        guac_audio_stream* audio, wStream* input_stream,
        guac_rdpsnd_pdu_header* header) {

    int data_size;
    wStream* output_stream;

    rdp_guac_client_data* guac_client_data =
        (rdp_guac_client_data*) audio->client->data;

    /* Read timestamp and data size */
    Stream_Read_UINT16(input_stream, rdpsnd->server_timestamp);
    Stream_Read_UINT16(input_stream, data_size);

    /* Send training response */
    output_stream = Stream_New(NULL, 8);
    Stream_Write_UINT8(output_stream, SNDC_TRAINING);
    Stream_Write_UINT8(output_stream, 0);
    Stream_Write_UINT16(output_stream, 4);
    Stream_Write_UINT16(output_stream, rdpsnd->server_timestamp);
    Stream_Write_UINT16(output_stream, data_size);

    pthread_mutex_lock(&(guac_client_data->rdp_lock));
    svc_plugin_send((rdpSvcPlugin*) rdpsnd, output_stream);
    pthread_mutex_unlock(&(guac_client_data->rdp_lock));

}

void guac_rdpsnd_wave_info_handler(guac_rdpsndPlugin* rdpsnd,
        guac_audio_stream* audio, wStream* input_stream,
        guac_rdpsnd_pdu_header* header) {

    unsigned char buffer[4];
    int format;

    /* Read wave information */
    Stream_Read_UINT16(input_stream, rdpsnd->server_timestamp);
    Stream_Read_UINT16(input_stream, format);
    Stream_Read_UINT8(input_stream, rdpsnd->waveinfo_block_number);
    Stream_Seek(input_stream, 3);
    Stream_Read(input_stream, buffer, 4);

    /*
     * Size of incoming wave data is equal to the body size field of this
     * header, less the size of a WaveInfo PDU (not including the header),
     * thus body_size - 12.
     */
    rdpsnd->incoming_wave_size = header->body_size - 12;

    /* Read wave in next iteration */
    rdpsnd->next_pdu_is_wave = TRUE;

    /* Init stream with requested format */
    guac_audio_stream_begin(audio,
            rdpsnd->formats[format].rate,
            rdpsnd->formats[format].channels,
            rdpsnd->formats[format].bps);

    /* Write initial 4 bytes of data */
    guac_audio_stream_write_pcm(audio, buffer, 4);

}

void guac_rdpsnd_wave_handler(guac_rdpsndPlugin* rdpsnd,
        guac_audio_stream* audio, wStream* input_stream,
        guac_rdpsnd_pdu_header* header) {

    rdpSvcPlugin* plugin = (rdpSvcPlugin*)rdpsnd;

    rdp_guac_client_data* guac_client_data =
        (rdp_guac_client_data*) audio->client->data;

    /* Wave Confirmation PDU */
    wStream* output_stream = Stream_New(NULL, 8);

    /* Get wave data */
    unsigned char* buffer = Stream_Buffer(input_stream) + 4;

    /* Write rest of audio packet */
    guac_audio_stream_write_pcm(audio, buffer, rdpsnd->incoming_wave_size);
    guac_audio_stream_end(audio);

    /* Write Wave Confirmation PDU */
    Stream_Write_UINT8(output_stream, SNDC_WAVECONFIRM);
    Stream_Write_UINT8(output_stream, 0);
    Stream_Write_UINT16(output_stream, 4);
    Stream_Write_UINT16(output_stream, rdpsnd->server_timestamp);
    Stream_Write_UINT8(output_stream, rdpsnd->waveinfo_block_number);
    Stream_Write_UINT8(output_stream, 0);

    /* Send Wave Confirmation PDU */
    pthread_mutex_lock(&(guac_client_data->rdp_lock));
    svc_plugin_send(plugin, output_stream);
    pthread_mutex_unlock(&(guac_client_data->rdp_lock));

    /* We no longer expect to receive wave data */
    rdpsnd->next_pdu_is_wave = FALSE;

}

void guac_rdpsnd_close_handler(guac_rdpsndPlugin* rdpsnd,
        guac_audio_stream* audio, wStream* input_stream,
        guac_rdpsnd_pdu_header* header) {

    /* STUB: Do nothing for now */

}