reactos/base/applications/mstsc/licence.c

   1 /* -*- c-basic-offset: 8 -*-
   2    rdesktop: A Remote Desktop Protocol client.
   3    RDP licensing negotiation
   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
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include <precomp.h>
  22 //#include <openssl/rc4.h>
  23
  24 void *
  25 ssl_rc4_info_create(void);
  26 void
  27 ssl_rc4_info_delete(void * rc4_info);
  28 void
  29 ssl_rc4_set_key(void * rc4_info, char * key, int len);
  30 void
  31 ssl_rc4_crypt(void * rc4_info, char * in_data, char * out_data, int len);
  32 int
  33 ssl_mod_exp(char* out, int out_len, char* in, int in_len,
  34             char* mod, int mod_len, char* exp, int exp_len);
  35
  36 extern char g_username[];
  37 extern char g_hostname[];
  38
  39 static uint8 g_licence_key[16];
  40 static uint8 g_licence_sign_key[16];
  41
  42 BOOL g_licence_issued = False;
  43
  44 /* Generate a session key and RC4 keys, given client and server randoms */
  45 static void
  46 licence_generate_keys(uint8 * client_random, uint8 * server_random, uint8 * pre_master_secret)
  47 {
  48         uint8 master_secret[48];
  49         uint8 key_block[48];
  50
  51         /* Generate master secret and then key material */
  52         sec_hash_48(master_secret, pre_master_secret, client_random, server_random, 'A');
  53         sec_hash_48(key_block, master_secret, server_random, client_random, 'A');
  54
  55         /* Store first 16 bytes of session key as MAC secret */
  56         memcpy(g_licence_sign_key, key_block, 16);
  57
  58         /* Generate RC4 key from next 16 bytes */
  59         sec_hash_16(g_licence_key, &key_block[16], client_random, server_random);
  60 }
  61
  62 static void
  63 licence_generate_hwid(uint8 * hwid)
  64 {
  65         buf_out_uint32(hwid, 2);
  66         strncpy((char *) (hwid + 4), g_hostname, LICENCE_HWID_SIZE - 4);
  67 }
  68
  69 /* Present an existing licence to the server */
  70 static void
  71 licence_present(uint8 * client_random, uint8 * rsa_data,
  72                 uint8 * licence_data, int licence_size, uint8 * hwid, uint8 * signature)
  73 {
  74         uint32 sec_flags = SEC_LICENCE_NEG;
  75         uint16 length =
  76                 16 + SEC_RANDOM_SIZE + SEC_MODULUS_SIZE + SEC_PADDING_SIZE +
  77                 licence_size + LICENCE_HWID_SIZE + LICENCE_SIGNATURE_SIZE;
  78         STREAM s;
  79
  80         s = sec_init(sec_flags, length + 4);
  81
  82         out_uint8(s, LICENCE_TAG_PRESENT);
  83         out_uint8(s, 2);        /* version */
  84         out_uint16_le(s, length);
  85
  86         out_uint32_le(s, 1);
  87         out_uint16(s, 0);
  88         out_uint16_le(s, 0x0201);
  89
  90         out_uint8p(s, client_random, SEC_RANDOM_SIZE);
  91         out_uint16(s, 0);
  92         out_uint16_le(s, (SEC_MODULUS_SIZE + SEC_PADDING_SIZE));
  93         out_uint8p(s, rsa_data, SEC_MODULUS_SIZE);
  94         out_uint8s(s, SEC_PADDING_SIZE);
  95
  96         out_uint16_le(s, 1);
  97         out_uint16_le(s, licence_size);
  98         out_uint8p(s, licence_data, licence_size);
  99
 100         out_uint16_le(s, 1);
 101         out_uint16_le(s, LICENCE_HWID_SIZE);
 102         out_uint8p(s, hwid, LICENCE_HWID_SIZE);
 103
 104         out_uint8p(s, signature, LICENCE_SIGNATURE_SIZE);
 105
 106         s_mark_end(s);
 107         sec_send(s, sec_flags);
 108 }
 109
 110 /* Send a licence request packet */
 111 static void
 112 licence_send_request(uint8 * client_random, uint8 * rsa_data, char *user, char *host)
 113 {
 114         uint32 sec_flags = SEC_LICENCE_NEG;
 115         uint16 userlen = strlen(user) + 1;
 116         uint16 hostlen = strlen(host) + 1;
 117         uint16 length = 128 + userlen + hostlen;
 118         STREAM s;
 119
 120         s = sec_init(sec_flags, length + 2);
 121
 122         out_uint8(s, LICENCE_TAG_REQUEST);
 123         out_uint8(s, 2);        /* version */
 124         out_uint16_le(s, length);
 125
 126         out_uint32_le(s, 1);
 127         out_uint16(s, 0);
 128         out_uint16_le(s, 0xff01);
 129
 130         out_uint8p(s, client_random, SEC_RANDOM_SIZE);
 131         out_uint16(s, 0);
 132         out_uint16_le(s, (SEC_MODULUS_SIZE + SEC_PADDING_SIZE));
 133         out_uint8p(s, rsa_data, SEC_MODULUS_SIZE);
 134         out_uint8s(s, SEC_PADDING_SIZE);
 135
 136         out_uint16_le(s, LICENCE_TAG_USER);
 137         out_uint16_le(s, userlen);
 138         out_uint8p(s, user, userlen);
 139
 140         out_uint16_le(s, LICENCE_TAG_HOST);
 141         out_uint16_le(s, hostlen);
 142         out_uint8p(s, host, hostlen);
 143
 144         s_mark_end(s);
 145         sec_send(s, sec_flags);
 146 }
 147
 148 /* Process a licence demand packet */
 149 static void
 150 licence_process_demand(STREAM s)
 151 {
 152         uint8 null_data[SEC_MODULUS_SIZE];
 153         uint8 *server_random;
 154         uint8 signature[LICENCE_SIGNATURE_SIZE];
 155         uint8 hwid[LICENCE_HWID_SIZE];
 156         uint8 *licence_data;
 157         int licence_size;
 158         void * crypt_key;
 159
 160         /* Retrieve the server random from the incoming packet */
 161         in_uint8p(s, server_random, SEC_RANDOM_SIZE);
 162
 163         /* We currently use null client keys. This is a bit naughty but, hey,
 164            the security of licence negotiation isn't exactly paramount. */
 165         memset(null_data, 0, sizeof(null_data));
 166         licence_generate_keys(null_data, server_random, null_data);
 167
 168         licence_size = load_licence(&licence_data);
 169         if (licence_size > 0)
 170         {
 171                 /* Generate a signature for the HWID buffer */
 172                 licence_generate_hwid(hwid);
 173                 sec_sign(signature, 16, g_licence_sign_key, 16, hwid, sizeof(hwid));
 174
 175                 /* Now encrypt the HWID */
 176                 crypt_key = ssl_rc4_info_create();
 177                 ssl_rc4_set_key(crypt_key, (char *)g_licence_key, 16);
 178                 ssl_rc4_crypt(crypt_key, (char *)hwid, (char *)hwid, sizeof(hwid));
 179                 ssl_rc4_info_delete(crypt_key);
 180
 181                 licence_present(null_data, null_data, licence_data, licence_size, hwid, signature);
 182                 xfree(licence_data);
 183                 return;
 184         }
 185
 186         licence_send_request(null_data, null_data, g_username, g_hostname);
 187 }
 188
 189 /* Send an authentication response packet */
 190 static void
 191 licence_send_authresp(uint8 * token, uint8 * crypt_hwid, uint8 * signature)
 192 {
 193         uint32 sec_flags = SEC_LICENCE_NEG;
 194         uint16 length = 58;
 195         STREAM s;
 196
 197         s = sec_init(sec_flags, length + 2);
 198
 199         out_uint8(s, LICENCE_TAG_AUTHRESP);
 200         out_uint8(s, 2);        /* version */
 201         out_uint16_le(s, length);
 202
 203         out_uint16_le(s, 1);
 204         out_uint16_le(s, LICENCE_TOKEN_SIZE);
 205         out_uint8p(s, token, LICENCE_TOKEN_SIZE);
 206
 207         out_uint16_le(s, 1);
 208         out_uint16_le(s, LICENCE_HWID_SIZE);
 209         out_uint8p(s, crypt_hwid, LICENCE_HWID_SIZE);
 210
 211         out_uint8p(s, signature, LICENCE_SIGNATURE_SIZE);
 212
 213         s_mark_end(s);
 214         sec_send(s, sec_flags);
 215 }
 216
 217 /* Parse an authentication request packet */
 218 static BOOL
 219 licence_parse_authreq(STREAM s, uint8 ** token, uint8 ** signature)
 220 {
 221         uint16 tokenlen;
 222
 223         in_uint8s(s, 6);        /* unknown: f8 3d 15 00 04 f6 */
 224
 225         in_uint16_le(s, tokenlen);
 226         if (tokenlen != LICENCE_TOKEN_SIZE)
 227         {
 228                 error("token len %d\n", tokenlen);
 229                 return False;
 230         }
 231
 232         in_uint8p(s, *token, tokenlen);
 233         in_uint8p(s, *signature, LICENCE_SIGNATURE_SIZE);
 234
 235         return s_check_end(s);
 236 }
 237
 238 /* Process an authentication request packet */
 239 static void
 240 licence_process_authreq(STREAM s)
 241 {
 242         uint8 *in_token = NULL, *in_sig;
 243         uint8 out_token[LICENCE_TOKEN_SIZE], decrypt_token[LICENCE_TOKEN_SIZE];
 244         uint8 hwid[LICENCE_HWID_SIZE], crypt_hwid[LICENCE_HWID_SIZE];
 245         uint8 sealed_buffer[LICENCE_TOKEN_SIZE + LICENCE_HWID_SIZE];
 246         uint8 out_sig[LICENCE_SIGNATURE_SIZE];
 247         void * crypt_key;
 248
 249         /* Parse incoming packet and save the encrypted token */
 250         licence_parse_authreq(s, &in_token, &in_sig);
 251         memcpy(out_token, in_token, LICENCE_TOKEN_SIZE);
 252
 253         /* Decrypt the token. It should read TEST in Unicode. */
 254         crypt_key = ssl_rc4_info_create();
 255         ssl_rc4_set_key(crypt_key, (char *)g_licence_key, 16);
 256         ssl_rc4_crypt(crypt_key, (char *)in_token, (char *)decrypt_token, LICENCE_TOKEN_SIZE);
 257         ssl_rc4_info_delete(crypt_key);
 258
 259         /* Generate a signature for a buffer of token and HWID */
 260         licence_generate_hwid(hwid);
 261         memcpy(sealed_buffer, decrypt_token, LICENCE_TOKEN_SIZE);
 262         memcpy(sealed_buffer + LICENCE_TOKEN_SIZE, hwid, LICENCE_HWID_SIZE);
 263         sec_sign(out_sig, 16, g_licence_sign_key, 16, sealed_buffer, sizeof(sealed_buffer));
 264
 265         /* Now encrypt the HWID */
 266         crypt_key = ssl_rc4_info_create();
 267         ssl_rc4_set_key(crypt_key, (char *)g_licence_key, 16);
 268         ssl_rc4_crypt(crypt_key, (char *)hwid, (char *)crypt_hwid, LICENCE_HWID_SIZE);
 269         ssl_rc4_info_delete(crypt_key);
 270
 271         licence_send_authresp(out_token, crypt_hwid, out_sig);
 272 }
 273
 274 /* Process an licence issue packet */
 275 static void
 276 licence_process_issue(STREAM s)
 277 {
 278         void * crypt_key;
 279         uint32 length;
 280         uint16 check;
 281         int i;
 282
 283         in_uint8s(s, 2);        /* 3d 45 - unknown */
 284         in_uint16_le(s, length);
 285         if (!s_check_rem(s, length))
 286                 return;
 287
 288         crypt_key = ssl_rc4_info_create();
 289         ssl_rc4_set_key(crypt_key, (char *)g_licence_key, 16);
 290         ssl_rc4_crypt(crypt_key, (char *)s->p, (char *)s->p, length);
 291         ssl_rc4_info_delete(crypt_key);
 292
 293         in_uint16(s, check);
 294         if (check != 0)
 295                 return;
 296
 297         g_licence_issued = True;
 298
 299         in_uint8s(s, 2);        /* pad */
 300
 301         /* advance to fourth string */
 302         length = 0;
 303         for (i = 0; i < 4; i++)
 304         {
 305                 in_uint8s(s, length);
 306                 in_uint32_le(s, length);
 307                 if (!s_check_rem(s, length))
 308                         return;
 309         }
 310
 311         g_licence_issued = True;
 312         save_licence(s->p, length);
 313 }
 314
 315 /* Process a licence packet */
 316 void
 317 licence_process(STREAM s)
 318 {
 319         uint8 tag;
 320
 321         in_uint8(s, tag);
 322         in_uint8s(s, 3);        /* version, length */
 323
 324         switch (tag)
 325         {
 326                 case LICENCE_TAG_DEMAND:
 327                         licence_process_demand(s);
 328                         break;
 329
 330                 case LICENCE_TAG_AUTHREQ:
 331                         licence_process_authreq(s);
 332                         break;
 333
 334                 case LICENCE_TAG_ISSUE:
 335                         licence_process_issue(s);
 336                         break;
 337
 338                 case LICENCE_TAG_REISSUE:
 339                 case LICENCE_TAG_RESULT:
 340                         break;
 341
 342                 default:
 343                         unimpl("licence tag 0x%x\n", tag);
 344         }
 345 }