diff options
Diffstat (limited to 'uirdesktop/channels.c')
| -rw-r--r-- | uirdesktop/channels.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/uirdesktop/channels.c b/uirdesktop/channels.c new file mode 100644 index 00000000..389cce2e --- /dev/null +++ b/uirdesktop/channels.c @@ -0,0 +1,181 @@ +/* -*- c-basic-offset: 8 -*- + rdesktop: A Remote Desktop Protocol client. + Protocol services - Virtual channels + Copyright (C) Erik Forsberg <forsberg@cendio.se> 2003 + Copyright (C) Matthew Chapman 2003-2005 + + 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. +*/ + +#include "rdesktop.h" + +#define MAX_CHANNELS 6 +#define CHANNEL_CHUNK_LENGTH 1600 +#define CHANNEL_FLAG_FIRST 0x01 +#define CHANNEL_FLAG_LAST 0x02 +#define CHANNEL_FLAG_SHOW_PROTOCOL 0x10 + +extern BOOL g_use_rdp5; +extern BOOL g_encryption; + +VCHANNEL g_channels[MAX_CHANNELS]; +unsigned int g_num_channels; + +/* FIXME: We should use the information in TAG_SRV_CHANNELS to map RDP5 + channels to MCS channels. + + The format of TAG_SRV_CHANNELS seems to be + + global_channel_no (uint16le) + number_of_other_channels (uint16le) + ..followed by uint16les for the other channels. +*/ + +VCHANNEL * +channel_register(char *name, uint32 flags, void (*callback) (STREAM)) +{ + VCHANNEL *channel; + + if (!g_use_rdp5) + return NULL; + + if (g_num_channels >= MAX_CHANNELS) + { + error("Channel table full, increase MAX_CHANNELS\n"); + return NULL; + } + + channel = &g_channels[g_num_channels]; + channel->mcs_id = MCS_GLOBAL_CHANNEL + 1 + g_num_channels; + strncpy(channel->name, name, 8); + channel->flags = flags; + channel->process = callback; + g_num_channels++; + return channel; +} + +STREAM +channel_init(VCHANNEL * channel, uint32 length) +{ + STREAM s; + + s = sec_init(g_encryption ? SEC_ENCRYPT : 0, length + 8); + s_push_layer(s, channel_hdr, 8); + return s; +} + +void +channel_send(STREAM s, VCHANNEL * channel) +{ + uint32 length, flags; + uint32 thislength, remaining; + uint8 *data; + + /* first fragment sent in-place */ + s_pop_layer(s, channel_hdr); + length = s->end - s->p - 8; + + DEBUG_CHANNEL(("channel_send, length = %d\n", length)); + + thislength = MIN(length, CHANNEL_CHUNK_LENGTH); +/* Note: In the original clipboard implementation, this number was + 1592, not 1600. However, I don't remember the reason and 1600 seems + to work so.. This applies only to *this* length, not the length of + continuation or ending packets. */ + remaining = length - thislength; + flags = (remaining == 0) ? CHANNEL_FLAG_FIRST | CHANNEL_FLAG_LAST : CHANNEL_FLAG_FIRST; + if (channel->flags & CHANNEL_OPTION_SHOW_PROTOCOL) + flags |= CHANNEL_FLAG_SHOW_PROTOCOL; + + out_uint32_le(s, length); + out_uint32_le(s, flags); + data = s->end = s->p + thislength; + DEBUG_CHANNEL(("Sending %d bytes with FLAG_FIRST\n", thislength)); + sec_send_to_channel(s, g_encryption ? SEC_ENCRYPT : 0, channel->mcs_id); + + /* subsequent segments copied (otherwise would have to generate headers backwards) */ + while (remaining > 0) + { + thislength = MIN(remaining, CHANNEL_CHUNK_LENGTH); + remaining -= thislength; + flags = (remaining == 0) ? CHANNEL_FLAG_LAST : 0; + if (channel->flags & CHANNEL_OPTION_SHOW_PROTOCOL) + flags |= CHANNEL_FLAG_SHOW_PROTOCOL; + + DEBUG_CHANNEL(("Sending %d bytes with flags %d\n", thislength, flags)); + + s = sec_init(g_encryption ? SEC_ENCRYPT : 0, thislength + 8); + out_uint32_le(s, length); + out_uint32_le(s, flags); + out_uint8p(s, data, thislength); + s_mark_end(s); + sec_send_to_channel(s, g_encryption ? SEC_ENCRYPT : 0, channel->mcs_id); + + data += thislength; + } +} + +void +channel_process(STREAM s, uint16 mcs_channel) +{ + uint32 length, flags; + uint32 thislength; + VCHANNEL *channel = NULL; + unsigned int i; + STREAM in; + + for (i = 0; i < g_num_channels; i++) + { + channel = &g_channels[i]; + if (channel->mcs_id == mcs_channel) + break; + } + + if (i >= g_num_channels) + return; + + in_uint32_le(s, length); + in_uint32_le(s, flags); + if ((flags & CHANNEL_FLAG_FIRST) && (flags & CHANNEL_FLAG_LAST)) + { + /* single fragment - pass straight up */ + channel->process(s); + } + else + { + /* add fragment to defragmentation buffer */ + in = &channel->in; + if (flags & CHANNEL_FLAG_FIRST) + { + if (length > in->size) + { + in->data = (uint8 *) xrealloc(in->data, length); + in->size = length; + } + in->p = in->data; + } + + thislength = MIN(s->end - s->p, in->data + in->size - in->p); + memcpy(in->p, s->p, thislength); + in->p += thislength; + + if (flags & CHANNEL_FLAG_LAST) + { + in->end = in->p; + in->p = in->data; + channel->process(in); + } + } +} |