o added support for dynamic virtual channels

o added echo test routine in simple.c for testing DVC using Microsoft's ECHO protocol

1 files changed, 500 insertions, 1 deletions

diff --git a/sesman/chansrv/drdynvc.c b/sesman/chansrv/drdynvc.c
index da0e8fe3..6bcac45e 100644
--- a/sesman/chansrv/drdynvc.c
+++ b/sesman/chansrv/drdynvc.c
@@ -1,7 +1,7 @@
 /**
  * xrdp: A Remote Desktop Protocol server.
  *
- * Copyright (C) Jay Sorg 2012
+ * Copyright (C) Laxmikant Rashinkar 2012 LK.Rashinkar@gmail.com
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,3 +15,502 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
+#include "drdynvc.h"
+
+int g_drdynvc_chan_id;
+int g_drdynvc_inited = 0;
+
+/**
+ * bring up dynamic virtual channel
+ *
+ * @return 0 on success, -1 on response
+ ******************************************************************************/
+int APP_CC
+drdynvc_init(void)
+{
+    /* bring up X11 */
+    xcommon_init();
+
+    /* let client know what version of DVC we support */
+    drdynvc_send_capability_request(2);
+
+    return 0;
+}
+
+/**
+ * let DVC Manager on client end know what version of protocol we support
+ * client will respond with version that it supports
+ *
+ * @return 0 on success, -1 on response
+ ******************************************************************************/
+static int APP_CC
+drdynvc_send_capability_request(uint16_t version)
+{
+    struct stream *s;
+    int bytes_in_stream;
+
+    /* setup stream */
+    make_stream(s);
+    init_stream(s, MAX_PDU_SIZE);
+
+    out_uint8(s, 0x50);         /* insert cmd       */
+    out_uint8(s, 0x00);         /* insert padding   */
+    out_uint16_le(s, version);  /* insert version   */
+
+    /* channel priority unused for now              */
+    out_uint16_le(s, 0x0000);  /* priority charge 0 */
+    out_uint16_le(s, 0x0000);  /* priority charge 1 */
+    out_uint16_le(s, 0x0000);  /* priority charge 2 */
+    out_uint16_le(s, 0x0000);  /* priority charge 3 */
+
+    /* send command to client */
+    bytes_in_stream = stream_length_before_p(s);
+    send_channel_data(g_drdynvc_chan_id, s->data, bytes_in_stream);
+    free_stream(s);
+
+    return 0;
+}
+
+/**
+ * process capability response received from DVC manager at client end
+ *
+ * @param s stream containing client response
+ *
+ * @return 0 on success, -1 on failure
+ ******************************************************************************/
+static int APP_CC
+drdynvc_process_capability_response(struct stream *s, unsigned char cmd)
+{
+    int cap_version;
+
+    /* skip padding */
+    in_uint8s(s, 1);
+
+    /* read client's version */
+    in_uint16_le(s, cap_version);
+
+    if (cap_version != 2)
+    {
+        LOG(0, ("drdynvc_process_capability_response: incompatible DVC version %d detected", cap_version));
+        return -1;
+    }
+
+    LOG(0, ("drdynvc_process_capability_response: DVC version 2 selected"));
+    g_drdynvc_inited = 1;
+
+    return 0;
+}
+
+/**
+ * create a new dynamic virtual channel
+ *
+ * @pram  channel_id    channel id number
+ * @pram  channel_name  name of channel
+ *
+ * @return 0 on success, -1 on failure
+ ******************************************************************************/
+int APP_CC
+drdynvc_send_open_channel_request(int chan_pri, unsigned int chan_id,
+                                  char *chan_name)
+{
+    struct stream *s;
+    int            bytes_in_stream;
+    int            cbChId;
+    int            name_length;
+
+    if ((chan_name == NULL) || (strlen(chan_name) == 0))
+    {
+        LOG(0, ("drdynvc_send_open_channel_request: bad channel name specified"));
+        return -1;
+    }
+
+    make_stream(s);
+    init_stream(s, MAX_PDU_SIZE);
+
+    name_length = strlen(chan_name);
+
+    /* dummy command for now */
+    out_uint8(s, 0);
+
+    /* insert channel id */
+    cbChId = drdynvc_insert_uint_124(s, chan_id);
+
+    /* insert channel name */
+    out_uint8a(s, chan_name, name_length + 1);
+
+    /* insert command */
+    s->data[0] = CMD_DVC_OPEN_CHANNEL | ((chan_pri << 2) & 0x0c) | cbChId;
+
+    /* send command */
+    bytes_in_stream = stream_length_before_p(s);
+    send_channel_data(g_drdynvc_chan_id, s->data, bytes_in_stream);
+    free_stream(s);
+
+    return 0;
+}
+
+static int APP_CC
+drdynvc_process_open_channel_response(struct stream *s, unsigned char cmd)
+{
+    struct xrdp_api_data *adp;
+
+    uint32_t chan_id;
+    int      creation_status;
+
+    drdynvc_get_chan_id(s, cmd, &chan_id);
+    in_uint32_le(s, creation_status);
+
+    /* LK_TODO now do something using useful! */
+
+    if (creation_status < 0)
+    {
+        // TODO
+    }
+    else
+    {
+        /* get struct xrdp_api_data containing this channel id */
+        if ((adp = struct_from_dvc_chan_id(chan_id)) == NULL)
+        {
+            LOG(0, ("drdynvc_process_open_channel_response: error : "
+                    "could not find xrdp_api_data containing chan_id %d", chan_id));
+
+            return -1;
+        }
+
+        adp->is_connected = 1;
+    }
+
+    return 0;
+}
+
+int APP_CC
+drdynvc_send_close_channel_request(unsigned int chan_id)
+{
+    struct stream *s;
+    int            bytes_in_stream;
+    int            cbChId;
+
+    make_stream(s);
+    init_stream(s, MAX_PDU_SIZE);
+
+    /* insert dummy cmd for now */
+    out_uint8(s, 0);
+
+    /* insert channel id */
+    cbChId = drdynvc_insert_uint_124(s, chan_id);
+
+    /* insert command */
+    s->data[0] = CMD_DVC_CLOSE_CHANNEL | cbChId;
+
+    /* send command */
+    bytes_in_stream = stream_length_before_p(s);
+    send_channel_data(g_drdynvc_chan_id, s->data, bytes_in_stream);
+
+    free_stream(s);
+    return 0;
+}
+
+static int APP_CC
+drdynvc_process_close_channel_response(struct stream *s, unsigned char cmd)
+{
+    uint32_t chan_id;
+
+    drdynvc_get_chan_id(s, cmd, &chan_id);
+
+    /* LK_TODO now do something using useful! */
+
+    return 0;
+}
+
+/*
+ * send data to client
+ *
+ * @param  chan_id    the virtual channel to write to
+ * @param  data       data to write
+ * @param  data_size  number of bytes to write
+ *
+ * @return 0 on success, -1 on failure
+ ******************************************************************************/
+int APP_CC drdynvc_write_data(uint32_t chan_id, char *data, int data_size)
+{
+    struct stream *s;
+    char          *saved_ptr;
+    int            cbChId;
+    int            Len;
+    int            bytes_in_stream;
+    int            frag_size;
+
+    if (data == NULL)
+    {
+        LOG(0, ("drdynvc_write_data: data is NULL\n"));
+        return -1;
+    }
+
+    if (data_size <= 0)
+    {
+        return 0;
+    }
+
+    make_stream(s);
+    init_stream(s, MAX_PDU_SIZE);
+
+    /* this is a dummy write */
+    out_uint8(s, 0);
+
+    /* insert channel id */
+    cbChId = drdynvc_insert_uint_124(s, chan_id);
+
+    /* will data fit into one pkt? */
+    bytes_in_stream = stream_length_before_p(s);
+
+    if ((bytes_in_stream + data_size) <= MAX_PDU_SIZE)
+    {
+        /* yes it will - insert data */
+        out_uint8p(s, data, data_size);
+
+        /* insert command */
+        s->data[0] = CMD_DVC_DATA | cbChId;
+
+        /* write data to client */
+        bytes_in_stream = stream_length_before_p(s);
+        send_channel_data(g_drdynvc_chan_id, s->data, bytes_in_stream);
+        free_stream(s);
+        return 0;
+    }
+
+    /* no it won't - fragment it */
+
+    saved_ptr = s->p;
+
+    /* let client know how much data to expect */
+    Len = drdynvc_insert_uint_124(s, data_size);
+
+    /* insert data into first fragment */
+    frag_size = MAX_PDU_SIZE - stream_length_before_p(s);
+    out_uint8p(s, data, frag_size);
+
+    /* insert command */
+    s->data[0] = CMD_DVC_DATA_FIRST | Len << 2 | cbChId;
+
+    /* write first fragment to client */
+    bytes_in_stream = stream_length_before_p(s);
+    send_channel_data(g_drdynvc_chan_id, s->data, bytes_in_stream);
+    data_size -= frag_size;
+    data += frag_size;
+    s->data[0] = CMD_DVC_DATA | cbChId;
+    s->p = saved_ptr;
+
+    /* now send rest of the data using CMD_DVC_DATA */
+    while (data_size > 0)
+    {
+        frag_size = MAX_PDU_SIZE - stream_length_before_p(s);
+
+        if (frag_size > data_size)
+        {
+            frag_size = data_size;
+        }
+
+        out_uint8p(s, data, frag_size);
+        bytes_in_stream = stream_length_before_p(s);
+        send_channel_data(g_drdynvc_chan_id, s->data, bytes_in_stream);
+        data_size -= frag_size;
+        data += frag_size;
+        s->p = saved_ptr;
+    }
+
+    free_stream(s);
+    return 0;
+}
+
+static int APP_CC
+drdynvc_process_data_first(struct stream *s, unsigned char cmd)
+{
+    struct xrdp_api_data *adp;
+    struct stream        *ls;
+
+    uint32_t chan_id;
+    int      bytes_in_stream;
+    int      data_len;
+    int      Len;
+
+    drdynvc_get_chan_id(s, cmd, &chan_id);
+
+    Len = (cmd >> 2) & 0x03;
+
+    if (Len == 0)
+    {
+        in_uint8(s, data_len);
+    }
+    else if (Len == 1)
+    {
+        in_uint16_le(s, data_len);
+    }
+    else
+    {
+        in_uint32_le(s, data_len);
+    }
+
+    bytes_in_stream = stream_length_after_p(s);
+
+    /* get struct xrdp_api_data containing this channel id */
+    if ((adp = struct_from_dvc_chan_id(chan_id)) == NULL)
+    {
+        LOG(0, ("drdynvc_process_data_first: error : "
+                "could not find xrdp_api_data containing chan_id %d", chan_id));
+
+        return -1;
+    }
+
+    ls = trans_get_out_s(adp->transp, MAX_PDU_SIZE);
+    out_uint8p(ls, s->p, bytes_in_stream);
+    s_mark_end(ls);
+    trans_force_write(adp->transp);
+
+    return 0;
+}
+
+static int APP_CC
+drdynvc_process_data(struct stream *s, unsigned char cmd)
+{
+    struct xrdp_api_data *adp;
+    struct stream        *ls;
+
+    uint32_t chan_id;
+    int      bytes_in_stream;
+
+    drdynvc_get_chan_id(s, cmd, &chan_id);
+    bytes_in_stream = stream_length_after_p(s);
+
+    /* get struct xrdp_api_data containing this channel id */
+    if ((adp = struct_from_dvc_chan_id(chan_id)) == NULL)
+    {
+        LOG(0, ("drdynvc_process_data: error : "
+                "could not find xrdp_api_data containing chan_id %d", chan_id));
+
+        return -1;
+    }
+
+    ls = trans_get_out_s(adp->transp, MAX_PDU_SIZE);
+    out_uint8p(ls, s->p, bytes_in_stream);
+    s_mark_end(ls);
+    trans_force_write(adp->transp);
+
+    return 0;
+}
+
+/**
+ * process incoming data on a dynamic virtual channel
+ *
+ * @pram  s             stream containing the incoming data
+ * @pram  chand_id      LK_TODO
+ * @pram  chan_flags    LK_TODO
+ * @pram  length        LK_TODO
+ * @pram  total_length  LK_TODO
+ *
+ * @return 0 on success, -1 on failure
+ ******************************************************************************/
+int APP_CC
+drdynvc_data_in(struct stream *s, int chan_id, int chan_flags, int length,
+                int total_length)
+{
+    unsigned char cmd;
+
+    in_uint8(s, cmd); /* read command */
+
+    switch (cmd & 0xf0)
+    {
+        case CMD_DVC_CAPABILITY:
+            drdynvc_process_capability_response(s, cmd);
+            break;
+
+        case CMD_DVC_OPEN_CHANNEL:
+            drdynvc_process_open_channel_response(s, cmd);
+            break;
+
+        case CMD_DVC_CLOSE_CHANNEL:
+            drdynvc_process_close_channel_response(s, cmd);
+            break;
+
+        case CMD_DVC_DATA_FIRST:
+            drdynvc_process_data_first(s, cmd);
+            break;
+
+        case CMD_DVC_DATA:
+            drdynvc_process_data(s, cmd);
+            break;
+
+        default:
+            LOG(0, ("drdynvc_data_in: got unknown command 0x%x", cmd));
+            break;
+    }
+
+    return 0;
+}
+
+/*
+ * insert a byte, short or 32bit value into specified stream
+ *
+ * @param  s    stream used for insertion
+ * @param  val  value to insert
+ *
+ * @return 0 for byte insertions
+ * @return 1 for short insertion
+ * @return 2 for uint32_t insertions
+ ******************************************************************************/
+static int APP_CC
+drdynvc_insert_uint_124(struct stream *s, uint32_t val)
+{
+    int ret_val;
+
+    if (val <= 0xff)
+    {
+        out_uint8(s, val);
+        ret_val = 0;
+    }
+    else if (val <= 0xffff)
+    {
+        out_uint16_le(s, val);
+        ret_val = 1;
+    }
+    else
+    {
+        out_uint32_le(s, val);
+        ret_val = 2;
+    }
+
+    return ret_val;
+}
+
+/*
+ * extract channel id from stream
+ *
+ * @param   s        stream containing channel id
+ * @param   cmd      first byte in stream
+ * @param   chan_id  return channel id  here
+ ******************************************************************************/
+static int APP_CC
+drdynvc_get_chan_id(struct stream *s, char cmd, uint32_t *chan_id_p)
+{
+    int cbChId;
+    int chan_id;
+
+    cbChId = cmd & 0x03;
+
+    if (cbChId == 0)
+    {
+        in_uint8(s, chan_id);
+    }
+    else if (cbChId == 1)
+    {
+        in_uint16_le(s, chan_id);
+    }
+    else
+    {
+        in_uint32_le(s, chan_id);
+    }
+
+    *chan_id_p = chan_id;
+
+    return 0;
+}