1 /* -*- c-basic-offset: 8 -*-
2 rdesktop: A Remote Desktop Protocol client.
3 Protocol services - Virtual channels
4 Copyright (C) Erik Forsberg <forsberg@cendio.se> 2003
5 Copyright (C) Matthew Chapman 2003
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #define MAX_CHANNELS 4
25 #define CHANNEL_CHUNK_LENGTH 1600
26 #define CHANNEL_FLAG_FIRST 0x01
27 #define CHANNEL_FLAG_LAST 0x02
28 #define CHANNEL_FLAG_SHOW_PROTOCOL 0x10
30 extern BOOL g_use_rdp5;
31 extern BOOL g_encryption;
33 VCHANNEL g_channels[MAX_CHANNELS];
34 unsigned int g_num_channels;
36 /* FIXME: We should use the information in TAG_SRV_CHANNELS to map RDP5
37 channels to MCS channels.
39 The format of TAG_SRV_CHANNELS seems to be
41 global_channel_no (uint16le)
42 number_of_other_channels (uint16le)
43 ..followed by uint16les for the other channels.
47 channel_register(char *name, uint32 flags, void (*callback) (STREAM))
51 if (g_num_channels >= MAX_CHANNELS)
53 error("Channel table full, increase MAX_CHANNELS\n");
57 channel = &g_channels[g_num_channels];
58 channel->mcs_id = MCS_GLOBAL_CHANNEL + 1 + g_num_channels;
59 strncpy(channel->name, name, 8);
60 channel->flags = flags;
61 channel->process = callback;
67 channel_init(VCHANNEL * channel, uint32 length)
71 s = sec_init(/*g_encryption ? SEC_ENCRYPT :*/ 0, length + 8);
72 s_push_layer(s, channel_hdr, 8);
77 channel_send(STREAM s, VCHANNEL * channel)
80 uint32 thislength, remaining;
83 /* first fragment sent in-place */
84 s_pop_layer(s, channel_hdr);
85 length = s->end - s->p - 8;
87 DEBUG_CLIPBOARD(("channel_send, length = %d\n", length));
89 thislength = MIN(length, CHANNEL_CHUNK_LENGTH);
90 /* Note: In the original clipboard implementation, this number was
91 1592, not 1600. However, I don't remember the reason and 1600 seems
92 to work so.. This applies only to *this* length, not the length of
93 continuation or ending packets. */
94 remaining = length - thislength;
95 flags = (remaining == 0) ? CHANNEL_FLAG_FIRST | CHANNEL_FLAG_LAST : CHANNEL_FLAG_FIRST;
96 if (channel->flags & CHANNEL_OPTION_SHOW_PROTOCOL)
97 flags |= CHANNEL_FLAG_SHOW_PROTOCOL;
99 out_uint32_le(s, length);
100 out_uint32_le(s, flags);
101 data = s->end = s->p + thislength;
102 DEBUG_CLIPBOARD(("Sending %d bytes with FLAG_FIRST\n", thislength));
103 sec_send_to_channel(s, /*g_encryption ? SEC_ENCRYPT :*/ 0, channel->mcs_id);
105 /* subsequent segments copied (otherwise would have to generate headers backwards) */
106 while (remaining > 0)
108 thislength = MIN(remaining, CHANNEL_CHUNK_LENGTH);
109 remaining -= thislength;
110 flags = (remaining == 0) ? CHANNEL_FLAG_LAST : 0;
111 if (channel->flags & CHANNEL_OPTION_SHOW_PROTOCOL)
112 flags |= CHANNEL_FLAG_SHOW_PROTOCOL;
114 DEBUG_CLIPBOARD(("Sending %d bytes with flags %d\n", thislength, flags));
116 s = sec_init(/*g_encryption ? SEC_ENCRYPT : */0, thislength + 8);
117 out_uint32_le(s, length);
118 out_uint32_le(s, flags);
119 out_uint8p(s, data, thislength);
121 sec_send_to_channel(s, /*g_encryption ? SEC_ENCRYPT : */0, channel->mcs_id);
128 channel_process(STREAM s, uint16 mcs_channel)
130 uint32 length, flags;
132 VCHANNEL *channel = NULL;
136 for (i = 0; i < g_num_channels; i++)
138 channel = &g_channels[i];
139 if (channel->mcs_id == mcs_channel)
143 if (i >= g_num_channels)
146 in_uint32_le(s, length);
147 in_uint32_le(s, flags);
148 if ((flags & CHANNEL_FLAG_FIRST) && (flags & CHANNEL_FLAG_LAST))
150 /* single fragment - pass straight up */
155 /* add fragment to defragmentation buffer */
157 if (flags & CHANNEL_FLAG_FIRST)
159 if (length > in->size)
161 in->data = xrealloc(in->data, length);
167 thislength = MIN(s->end - s->p, in->data + in->size - in->p);
168 memcpy(in->p, s->p, thislength);
171 if (flags & CHANNEL_FLAG_LAST)
175 channel->process(in);