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 2003-2005 6 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. 11 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. 16 17 You should have received a copy of the GNU General Public License along 18 with this program; if not, write to the Free Software Foundation, Inc., 19 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 20 */ 21 22 #include "rdesktop.h" 23 24 // FIXME: header mess 25 #if 0 26 #define CHANNEL_CHUNK_LENGTH 1600 27 #define CHANNEL_FLAG_FIRST 0x01 28 #define CHANNEL_FLAG_LAST 0x02 29 #define CHANNEL_FLAG_SHOW_PROTOCOL 0x10 30 #endif 31 32 /* FIXME: We should use the information in TAG_SRV_CHANNELS to map RDP5 33 channels to MCS channels. 34 35 The format of TAG_SRV_CHANNELS seems to be 36 37 global_channel_no (uint16le) 38 number_of_other_channels (uint16le) 39 ..followed by uint16les for the other channels. 40 */ 41 42 VCHANNEL * 43 channel_register(RDPCLIENT * This, char *name, uint32 flags, void (*callback) (RDPCLIENT *, STREAM)) 44 { 45 VCHANNEL *channel; 46 47 if (!This->use_rdp5) 48 return NULL; 49 50 if (This->num_channels >= MAX_CHANNELS) 51 { 52 error("Channel table full, increase MAX_CHANNELS\n"); 53 return NULL; 54 } 55 56 channel = &This->channels[This->num_channels]; 57 channel->mcs_id = MCS_GLOBAL_CHANNEL + 1 + This->num_channels; 58 strncpy(channel->name, name, 8); 59 channel->flags = flags; 60 channel->process = callback; 61 This->num_channels++; 62 return channel; 63 } 64 65 STREAM 66 channel_init(RDPCLIENT * This, VCHANNEL * channel, uint32 length) 67 { 68 STREAM s; 69 70 s = sec_init(This, This->encryption ? SEC_ENCRYPT : 0, length + 8); 71 s_push_layer(s, channel_hdr, 8); 72 return s; 73 } 74 75 void 76 channel_send(RDPCLIENT * This, STREAM s, VCHANNEL * channel) 77 { 78 uint32 length, flags; 79 uint32 thislength, remaining; 80 uint8 *data; 81 82 /* first fragment sent in-place */ 83 s_pop_layer(s, channel_hdr); 84 length = s->end - s->p - sizeof(CHANNEL_PDU_HEADER); 85 86 DEBUG_CHANNEL(("channel_send, length = %d\n", length)); 87 88 thislength = MIN(length, CHANNEL_CHUNK_LENGTH); 89 /* Note: In the original clipboard implementation, this number was 90 1592, not 1600. However, I don't remember the reason and 1600 seems 91 to work so.. This applies only to *this* length, not the length of 92 continuation or ending packets. */ 93 remaining = length - thislength; 94 flags = (remaining == 0) ? CHANNEL_FLAG_FIRST | CHANNEL_FLAG_LAST : CHANNEL_FLAG_FIRST; 95 if (channel->flags & CHANNEL_OPTION_SHOW_PROTOCOL) 96 flags |= CHANNEL_FLAG_SHOW_PROTOCOL; 97 98 out_uint32_le(s, length); 99 out_uint32_le(s, flags); 100 data = s->end = s->p + thislength; 101 DEBUG_CHANNEL(("Sending %d bytes with FLAG_FIRST\n", thislength)); 102 sec_send_to_channel(This, s, This->encryption ? SEC_ENCRYPT : 0, channel->mcs_id); 103 104 /* subsequent segments copied (otherwise would have to generate headers backwards) */ 105 while (remaining > 0) 106 { 107 thislength = MIN(remaining, CHANNEL_CHUNK_LENGTH); 108 remaining -= thislength; 109 flags = (remaining == 0) ? CHANNEL_FLAG_LAST : 0; 110 if (channel->flags & CHANNEL_OPTION_SHOW_PROTOCOL) 111 flags |= CHANNEL_FLAG_SHOW_PROTOCOL; 112 113 DEBUG_CHANNEL(("Sending %d bytes with flags %d\n", thislength, flags)); 114 115 s = sec_init(This, This->encryption ? SEC_ENCRYPT : 0, thislength + 8); 116 out_uint32_le(s, length); 117 out_uint32_le(s, flags); 118 out_uint8p(s, data, thislength); 119 s_mark_end(s); 120 sec_send_to_channel(This, s, This->encryption ? SEC_ENCRYPT : 0, channel->mcs_id); 121 122 data += thislength; 123 } 124 } 125 126 void 127 channel_process(RDPCLIENT * This, STREAM s, uint16 mcs_channel) 128 { 129 uint32 length, flags; 130 uint32 thislength; 131 VCHANNEL *channel = NULL; 132 unsigned int i; 133 STREAM in; 134 135 for (i = 0; i < This->num_channels; i++) 136 { 137 channel = &This->channels[i]; 138 if (channel->mcs_id == mcs_channel) 139 break; 140 } 141 142 if (i >= This->num_channels) 143 return; 144 145 in_uint32_le(s, length); 146 in_uint32_le(s, flags); 147 if ((flags & CHANNEL_FLAG_FIRST) && (flags & CHANNEL_FLAG_LAST)) 148 { 149 /* single fragment - pass straight up */ 150 channel->process(This, s); 151 } 152 else 153 { 154 /* add fragment to defragmentation buffer */ 155 in = &channel->in; 156 if (flags & CHANNEL_FLAG_FIRST) 157 { 158 if (length > in->size) 159 { 160 in->data = (uint8 *) xrealloc(in->data, length); 161 in->size = length; 162 } 163 in->p = in->data; 164 } 165 166 thislength = MIN(s->end - s->p, in->data + in->size - in->p); 167 memcpy(in->p, s->p, thislength); 168 in->p += thislength; 169 170 if (flags & CHANNEL_FLAG_LAST) 171 { 172 in->end = in->p; 173 in->p = in->data; 174 channel->process(This, in); 175 } 176 } 177 } 178