base/applications/mstsc/iso.c

   1 /* -*- c-basic-offset: 8 -*-
   2    rdesktop: A Remote Desktop Protocol client.
   3    Protocol services - ISO layer
   4    Copyright (C) Matthew Chapman 1999-2005
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License along
  17    with this program; if not, write to the Free Software Foundation, Inc.,
  18    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19 */
  20
  21 #include <precomp.h>
  22
  23 /* Send a self-contained ISO PDU */
  24 static void
  25 iso_send_msg(uint8 code)
  26 {
  27         STREAM s;
  28
  29         s = tcp_init(11);
  30
  31         out_uint8(s, 3);        /* version */
  32         out_uint8(s, 0);        /* reserved */
  33         out_uint16_be(s, 11);   /* length */
  34
  35         out_uint8(s, 6);        /* hdrlen */
  36         out_uint8(s, code);
  37         out_uint16(s, 0);       /* dst_ref */
  38         out_uint16(s, 0);       /* src_ref */
  39         out_uint8(s, 0);        /* class */
  40
  41         s_mark_end(s);
  42         tcp_send(s);
  43 }
  44
  45 static void
  46 iso_send_connection_request(char *username)
  47 {
  48         STREAM s;
  49         int length = 30 + strlen(username);
  50
  51         s = tcp_init(length);
  52
  53         out_uint8(s, 3);        /* version */
  54         out_uint8(s, 0);        /* reserved */
  55         out_uint16_be(s, length);       /* length */
  56
  57         out_uint8(s, length - 5);       /* hdrlen */
  58         out_uint8(s, ISO_PDU_CR);
  59         out_uint16(s, 0);       /* dst_ref */
  60         out_uint16(s, 0);       /* src_ref */
  61         out_uint8(s, 0);        /* class */
  62
  63         out_uint8p(s, "Cookie: mstshash=", strlen("Cookie: mstshash="));
  64         out_uint8p(s, username, strlen(username));
  65
  66         out_uint8(s, 0x0d);     /* Unknown */
  67         out_uint8(s, 0x0a);     /* Unknown */
  68
  69         s_mark_end(s);
  70         tcp_send(s);
  71 }
  72
  73 /* Receive a message on the ISO layer, return code */
  74 static STREAM
  75 iso_recv_msg(uint8 * code, uint8 * rdpver)
  76 {
  77         STREAM s;
  78         uint16 length;
  79         uint8 version;
  80
  81         s = tcp_recv(NULL, 4);
  82         if (s == NULL)
  83                 return NULL;
  84         in_uint8(s, version);
  85         if (rdpver != NULL)
  86                 *rdpver = version;
  87         if (version == 3)
  88         {
  89                 in_uint8s(s, 1);        /* pad */
  90                 in_uint16_be(s, length);
  91         }
  92         else
  93         {
  94                 in_uint8(s, length);
  95                 if (length & 0x80)
  96                 {
  97                         length &= ~0x80;
  98                         next_be(s, length);
  99                 }
 100         }
 101         s = tcp_recv(s, length - 4);
 102         if (s == NULL)
 103                 return NULL;
 104         if (version != 3)
 105                 return s;
 106         in_uint8s(s, 1);        /* hdrlen */
 107         in_uint8(s, *code);
 108         if (*code == ISO_PDU_DT)
 109         {
 110                 in_uint8s(s, 1);        /* eot */
 111                 return s;
 112         }
 113         in_uint8s(s, 5);        /* dst_ref, src_ref, class */
 114         return s;
 115 }
 116
 117 /* Initialise ISO transport data packet */
 118 STREAM
 119 iso_init(int length)
 120 {
 121         STREAM s;
 122
 123         s = tcp_init(length + 7);
 124         s_push_layer(s, iso_hdr, 7);
 125
 126         return s;
 127 }
 128
 129 /* Send an ISO data PDU */
 130 void
 131 iso_send(STREAM s)
 132 {
 133         uint16 length;
 134
 135         s_pop_layer(s, iso_hdr);
 136         length = s->end - s->p;
 137
 138         out_uint8(s, 3);        /* version */
 139         out_uint8(s, 0);        /* reserved */
 140         out_uint16_be(s, length);
 141
 142         out_uint8(s, 2);        /* hdrlen */
 143         out_uint8(s, ISO_PDU_DT);       /* code */
 144         out_uint8(s, 0x80);     /* eot */
 145
 146         tcp_send(s);
 147 }
 148
 149 /* Receive ISO transport data packet */
 150 STREAM
 151 iso_recv(uint8 * rdpver)
 152 {
 153         STREAM s;
 154         uint8 code = 0;
 155
 156         s = iso_recv_msg(&code, rdpver);
 157         if (s == NULL)
 158                 return NULL;
 159         if (rdpver != NULL)
 160                 if (*rdpver != 3)
 161                         return s;
 162         if (code != ISO_PDU_DT)
 163         {
 164                 error("expected DT, got 0x%x\n", code);
 165                 return NULL;
 166         }
 167         return s;
 168 }
 169
 170 /* Establish a connection up to the ISO layer */
 171 BOOL
 172 iso_connect(char *server, char *username)
 173 {
 174         uint8 code = 0;
 175
 176         if (!tcp_connect(server))
 177                 return False;
 178
 179         iso_send_connection_request(username);
 180
 181         if (iso_recv_msg(&code, NULL) == NULL)
 182                 return False;
 183
 184         if (code != ISO_PDU_CC)
 185         {
 186                 error("expected CC, got 0x%x\n", code);
 187                 tcp_disconnect();
 188                 return False;
 189         }
 190
 191         return True;
 192 }
 193
 194 /* Establish a reconnection up to the ISO layer */
 195 BOOL
 196 iso_reconnect(char *server)
 197 {
 198         uint8 code = 0;
 199
 200         if (!tcp_connect(server))
 201                 return False;
 202
 203         iso_send_msg(ISO_PDU_CR);
 204
 205         if (iso_recv_msg(&code, NULL) == NULL)
 206                 return False;
 207
 208         if (code != ISO_PDU_CC)
 209         {
 210                 error("expected CC, got 0x%x\n", code);
 211                 tcp_disconnect();
 212                 return False;
 213         }
 214
 215         return True;
 216 }
 217
 218 /* Disconnect from the ISO layer */
 219 void
 220 iso_disconnect(void)
 221 {
 222         iso_send_msg(ISO_PDU_DR);
 223         tcp_disconnect();
 224 }
 225
 226 /* reset the state to support reconnecting */
 227 void
 228 iso_reset_state(void)
 229 {
 230         tcp_reset_state();
 231 }