1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219
|
/* -*- c-basic-offset: 8 -*-
rdesktop: A Remote Desktop Protocol client.
Protocol services - Virtual channels
Copyright 2003 Erik Forsberg <forsberg@cendio.se> for Cendio AB
Copyright (C) Matthew Chapman <matthewc.unsw.edu.au> 2003-2008
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 3 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, see <http://www.gnu.org/licenses/>.
*/
#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 RDP_VERSION g_rdp_version;
extern RD_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_rdp_version < RDP_V5)
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;
}
static void
channel_send_chunk(STREAM s, VCHANNEL * channel, uint32 length)
{
uint32 flags;
uint32 thislength;
RD_BOOL inplace;
STREAM chunk;
/* 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. */
thislength = MIN(s_remaining(s), CHANNEL_CHUNK_LENGTH);
flags = 0;
if (length == s_remaining(s))
{
flags |= CHANNEL_FLAG_FIRST;
}
if (s_remaining(s) == thislength)
{
flags |= CHANNEL_FLAG_LAST;
}
if (channel->flags & CHANNEL_OPTION_SHOW_PROTOCOL)
{
flags |= CHANNEL_FLAG_SHOW_PROTOCOL;
}
DEBUG_CHANNEL(("channel_send_chunk(), sending %d bytes with flags 0x%x\n",
thislength, flags));
/* first fragment sent in-place */
inplace = False;
if ((flags & (CHANNEL_FLAG_FIRST|CHANNEL_FLAG_LAST)) ==
(CHANNEL_FLAG_FIRST|CHANNEL_FLAG_LAST))
{
inplace = True;
}
if (inplace)
{
s_pop_layer(s, channel_hdr);
chunk = s;
}
else
{
chunk = sec_init(g_encryption ? SEC_ENCRYPT : 0, thislength + 8);
}
out_uint32_le(chunk, length);
out_uint32_le(chunk, flags);
if (!inplace)
{
out_uint8stream(chunk, s, thislength);
s_mark_end(chunk);
}
sec_send_to_channel(chunk, g_encryption ? SEC_ENCRYPT : 0, channel->mcs_id);
/* Sending modifies the current offset, so make it is marked as
fully completed. */
if (inplace)
{
in_uint8s(s, s_remaining(s));
}
if (!inplace)
{
s_free(chunk);
}
}
void
channel_send(STREAM s, VCHANNEL * channel)
{
uint32 length;
#ifdef WITH_SCARD
scard_lock(SCARD_LOCK_CHANNEL);
#endif
s_pop_layer(s, channel_hdr);
in_uint8s(s, 8);
length = s_remaining(s);
DEBUG_CHANNEL(("channel_send, length = %d\n", length));
while (!s_check_end(s))
{
channel_send_chunk(s, channel, length);
}
#ifdef WITH_SCARD
scard_unlock(SCARD_LOCK_CHANNEL);
#endif
}
void
channel_process(STREAM s, uint16 mcs_channel)
{
uint32 length, flags;
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)
{
s_realloc(in, length);
s_reset(in);
}
out_uint8stream(in, s, s_remaining(s));
if (flags & CHANNEL_FLAG_LAST)
{
s_mark_end(in);
s_seek(in, 0);
channel->process(in);
}
}
}
|