/* This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. xrdp: A Remote Desktop Protocol server. Copyright (C) Jay Sorg 2006-2010 channel layer */ #include "libxrdp.h" /* todo, move these to constants.h */ //#define CHANNEL_CHUNK_LENGTH 1600 /* todo, why is this so small? */ #define CHANNEL_CHUNK_LENGTH 8192 #define CHANNEL_FLAG_FIRST 0x01 #define CHANNEL_FLAG_LAST 0x02 #define CHANNEL_FLAG_SHOW_PROTOCOL 0x10 /*****************************************************************************/ /* returns pointer or nil on error */ static struct mcs_channel_item* APP_CC xrdp_channel_get_item(struct xrdp_channel* self, int channel_id) { struct mcs_channel_item* channel; channel = (struct mcs_channel_item*) list_get_item(self->mcs_layer->channel_list, channel_id); return channel; } /*****************************************************************************/ struct xrdp_channel* APP_CC xrdp_channel_create(struct xrdp_sec* owner, struct xrdp_mcs* mcs_layer) { struct xrdp_channel* self; self = (struct xrdp_channel*)g_malloc(sizeof(struct xrdp_channel), 1); self->sec_layer = owner; self->mcs_layer = mcs_layer; return self; } /*****************************************************************************/ /* returns error */ void APP_CC xrdp_channel_delete(struct xrdp_channel* self) { if (self == 0) { return; } g_free(self); } /*****************************************************************************/ /* returns error */ int APP_CC xrdp_channel_init(struct xrdp_channel* self, struct stream* s) { if (xrdp_sec_init(self->sec_layer, s) != 0) { return 1; } s_push_layer(s, channel_hdr, 8); return 0; } /*****************************************************************************/ /* returns error */ /* This sends data out to the secure layer. */ int APP_CC xrdp_channel_send(struct xrdp_channel* self, struct stream* s, int channel_id, int total_data_len, int flags) { struct mcs_channel_item* channel; channel = xrdp_channel_get_item(self, channel_id); if (channel == 0) { return 1; } s_pop_layer(s, channel_hdr); out_uint32_le(s, total_data_len); if (channel->flags & CHANNEL_OPTION_SHOW_PROTOCOL) { flags |= CHANNEL_FLAG_SHOW_PROTOCOL; } out_uint32_le(s, flags); if (xrdp_sec_send(self->sec_layer, s, channel->chanid) != 0) { return 1; } return 0; } /*****************************************************************************/ /* returns error */ /* this will inform the callback, whatever it is that some channel data is ready. the default for this is a call to xrdp_wm.c. */ static int APP_CC xrdp_channel_call_callback(struct xrdp_channel* self, struct stream* s, int channel_id, int total_data_len, int flags) { struct xrdp_session* session; int rv; int size; rv = 0; session = self->sec_layer->rdp_layer->session; if (session != 0) { if (session->callback != 0) { size = (int)(s->end - s->p); /* in xrdp_wm.c */ rv = session->callback(session->id, 0x5555, MAKELONG(channel_id, flags), size, (tbus)(s->p), total_data_len); } else { g_writeln("in xrdp_channel_call_callback, session->callback is nil"); } } else { g_writeln("in xrdp_channel_call_callback, session is nil"); } return rv; } /*****************************************************************************/ /* returns error */ /* This is called from the secure layer to process an incomming non global channel packet. 'chanid' passed in here is the mcs channel id so it MCS_GLOBAL_CHANNEL plus something. */ int APP_CC xrdp_channel_process(struct xrdp_channel* self, struct stream* s, int chanid) { int length; int flags; int rv; int channel_id; struct mcs_channel_item* channel; /* this assumes that the channels are in order of chanid(mcs channel id) but they should be, see xrdp_sec_process_mcs_data_channels the first channel should be MCS_GLOBAL_CHANNEL + 1, second one should be MCS_GLOBAL_CHANNEL + 2, and so on */ channel_id = (chanid - MCS_GLOBAL_CHANNEL) - 1; channel = xrdp_channel_get_item(self, channel_id); if (channel == 0) { g_writeln("xrdp_channel_process, channel not found"); return 1; } rv = 0; in_uint32_le(s, length); in_uint32_le(s, flags); rv = xrdp_channel_call_callback(self, s, channel_id, length, flags); return rv; }