| 1 | /* |
| 2 | * Platform-independent bits of X11 forwarding. |
| 3 | */ |
| 4 | |
| 5 | #include <stdio.h> |
| 6 | #include <stdlib.h> |
| 7 | #include <assert.h> |
| 8 | #include <time.h> |
| 9 | |
| 10 | #include "putty.h" |
| 11 | #include "ssh.h" |
| 12 | #include "tree234.h" |
| 13 | |
| 14 | #define GET_32BIT_LSB_FIRST(cp) \ |
| 15 | (((unsigned long)(unsigned char)(cp)[0]) | \ |
| 16 | ((unsigned long)(unsigned char)(cp)[1] << 8) | \ |
| 17 | ((unsigned long)(unsigned char)(cp)[2] << 16) | \ |
| 18 | ((unsigned long)(unsigned char)(cp)[3] << 24)) |
| 19 | |
| 20 | #define PUT_32BIT_LSB_FIRST(cp, value) ( \ |
| 21 | (cp)[0] = (char)(value), \ |
| 22 | (cp)[1] = (char)((value) >> 8), \ |
| 23 | (cp)[2] = (char)((value) >> 16), \ |
| 24 | (cp)[3] = (char)((value) >> 24) ) |
| 25 | |
| 26 | #define GET_16BIT_LSB_FIRST(cp) \ |
| 27 | (((unsigned long)(unsigned char)(cp)[0]) | \ |
| 28 | ((unsigned long)(unsigned char)(cp)[1] << 8)) |
| 29 | |
| 30 | #define PUT_16BIT_LSB_FIRST(cp, value) ( \ |
| 31 | (cp)[0] = (char)(value), \ |
| 32 | (cp)[1] = (char)((value) >> 8) ) |
| 33 | |
| 34 | #define GET_32BIT_MSB_FIRST(cp) \ |
| 35 | (((unsigned long)(unsigned char)(cp)[0] << 24) | \ |
| 36 | ((unsigned long)(unsigned char)(cp)[1] << 16) | \ |
| 37 | ((unsigned long)(unsigned char)(cp)[2] << 8) | \ |
| 38 | ((unsigned long)(unsigned char)(cp)[3])) |
| 39 | |
| 40 | #define PUT_32BIT_MSB_FIRST(cp, value) ( \ |
| 41 | (cp)[0] = (char)((value) >> 24), \ |
| 42 | (cp)[1] = (char)((value) >> 16), \ |
| 43 | (cp)[2] = (char)((value) >> 8), \ |
| 44 | (cp)[3] = (char)(value) ) |
| 45 | |
| 46 | #define GET_16BIT_MSB_FIRST(cp) \ |
| 47 | (((unsigned long)(unsigned char)(cp)[0] << 8) | \ |
| 48 | ((unsigned long)(unsigned char)(cp)[1])) |
| 49 | |
| 50 | #define PUT_16BIT_MSB_FIRST(cp, value) ( \ |
| 51 | (cp)[0] = (char)((value) >> 8), \ |
| 52 | (cp)[1] = (char)(value) ) |
| 53 | |
| 54 | #define GET_16BIT(endian, cp) \ |
| 55 | (endian=='B' ? GET_16BIT_MSB_FIRST(cp) : GET_16BIT_LSB_FIRST(cp)) |
| 56 | |
| 57 | #define PUT_16BIT(endian, cp, val) \ |
| 58 | (endian=='B' ? PUT_16BIT_MSB_FIRST(cp, val) : PUT_16BIT_LSB_FIRST(cp, val)) |
| 59 | |
| 60 | const char *const x11_authnames[] = { |
| 61 | "", "MIT-MAGIC-COOKIE-1", "XDM-AUTHORIZATION-1" |
| 62 | }; |
| 63 | |
| 64 | struct XDMSeen { |
| 65 | unsigned int time; |
| 66 | unsigned char clientid[6]; |
| 67 | }; |
| 68 | |
| 69 | struct X11Auth { |
| 70 | unsigned char fakedata[64], realdata[64]; |
| 71 | int fakeproto, realproto; |
| 72 | int fakelen, reallen; |
| 73 | tree234 *xdmseen; |
| 74 | }; |
| 75 | |
| 76 | struct X11Private { |
| 77 | const struct plug_function_table *fn; |
| 78 | /* the above variable absolutely *must* be the first in this structure */ |
| 79 | unsigned char firstpkt[12]; /* first X data packet */ |
| 80 | struct X11Auth *auth; |
| 81 | char *auth_protocol; |
| 82 | unsigned char *auth_data; |
| 83 | int data_read, auth_plen, auth_psize, auth_dlen, auth_dsize; |
| 84 | int verified; |
| 85 | int throttled, throttle_override; |
| 86 | unsigned long peer_ip; |
| 87 | int peer_port; |
| 88 | void *c; /* data used by ssh.c */ |
| 89 | Socket s; |
| 90 | }; |
| 91 | |
| 92 | static int xdmseen_cmp(void *a, void *b) |
| 93 | { |
| 94 | struct XDMSeen *sa = a, *sb = b; |
| 95 | return sa->time > sb->time ? 1 : |
| 96 | sa->time < sb->time ? -1 : |
| 97 | memcmp(sa->clientid, sb->clientid, sizeof(sa->clientid)); |
| 98 | } |
| 99 | |
| 100 | void *x11_invent_auth(char *proto, int protomaxlen, |
| 101 | char *data, int datamaxlen, int proto_id) |
| 102 | { |
| 103 | struct X11Auth *auth = snew(struct X11Auth); |
| 104 | char ourdata[64]; |
| 105 | int i; |
| 106 | |
| 107 | if (proto_id == X11_MIT) { |
| 108 | auth->fakeproto = X11_MIT; |
| 109 | |
| 110 | /* MIT-MAGIC-COOKIE-1. Cookie size is 128 bits (16 bytes). */ |
| 111 | auth->fakelen = 16; |
| 112 | for (i = 0; i < 16; i++) |
| 113 | auth->fakedata[i] = random_byte(); |
| 114 | } else { |
| 115 | assert(proto_id == X11_XDM); |
| 116 | auth->fakeproto = X11_XDM; |
| 117 | |
| 118 | /* XDM-AUTHORIZATION-1. Cookie size is 16 bytes; byte 8 is zero. */ |
| 119 | auth->fakelen = 16; |
| 120 | for (i = 0; i < 16; i++) |
| 121 | auth->fakedata[i] = (i == 8 ? 0 : random_byte()); |
| 122 | auth->xdmseen = newtree234(xdmseen_cmp); |
| 123 | } |
| 124 | |
| 125 | /* Now format for the recipient. */ |
| 126 | strncpy(proto, x11_authnames[auth->fakeproto], protomaxlen); |
| 127 | ourdata[0] = '\0'; |
| 128 | for (i = 0; i < auth->fakelen; i++) |
| 129 | sprintf(ourdata + strlen(ourdata), "%02x", auth->fakedata[i]); |
| 130 | strncpy(data, ourdata, datamaxlen); |
| 131 | |
| 132 | return auth; |
| 133 | } |
| 134 | |
| 135 | void x11_free_auth(void *authv) |
| 136 | { |
| 137 | struct X11Auth *auth = (struct X11Auth *)authv; |
| 138 | struct XDMSeen *seen; |
| 139 | |
| 140 | if (auth->xdmseen != NULL) { |
| 141 | while ((seen = delpos234(auth->xdmseen, 0)) != NULL) |
| 142 | sfree(seen); |
| 143 | freetree234(auth->xdmseen); |
| 144 | } |
| 145 | sfree(auth); |
| 146 | } |
| 147 | |
| 148 | /* |
| 149 | * Fetch the real auth data for a given display string, and store |
| 150 | * it in an X11Auth structure. Returns NULL on success, or an error |
| 151 | * string. |
| 152 | */ |
| 153 | void x11_get_real_auth(void *authv, char *display) |
| 154 | { |
| 155 | struct X11Auth *auth = (struct X11Auth *)authv; |
| 156 | |
| 157 | auth->realproto = X11_NO_AUTH; /* in case next call does nothing */ |
| 158 | |
| 159 | auth->reallen = sizeof(auth->realdata); |
| 160 | platform_get_x11_auth(display, &auth->realproto, |
| 161 | auth->realdata, &auth->reallen); |
| 162 | } |
| 163 | |
| 164 | #define XDM_MAXSKEW 20*60 /* 20 minute clock skew should be OK */ |
| 165 | |
| 166 | static char *x11_verify(unsigned long peer_ip, int peer_port, |
| 167 | struct X11Auth *auth, char *proto, |
| 168 | unsigned char *data, int dlen) |
| 169 | { |
| 170 | if (strcmp(proto, x11_authnames[auth->fakeproto]) != 0) |
| 171 | return "wrong authentication protocol attempted"; |
| 172 | if (auth->fakeproto == X11_MIT) { |
| 173 | if (dlen != auth->fakelen) |
| 174 | return "MIT-MAGIC-COOKIE-1 data was wrong length"; |
| 175 | if (memcmp(auth->fakedata, data, dlen) != 0) |
| 176 | return "MIT-MAGIC-COOKIE-1 data did not match"; |
| 177 | } |
| 178 | if (auth->fakeproto == X11_XDM) { |
| 179 | unsigned long t; |
| 180 | time_t tim; |
| 181 | int i; |
| 182 | struct XDMSeen *seen, *ret; |
| 183 | |
| 184 | if (dlen != 24) |
| 185 | return "XDM-AUTHORIZATION-1 data was wrong length"; |
| 186 | if (peer_port == -1) |
| 187 | return "cannot do XDM-AUTHORIZATION-1 without remote address data"; |
| 188 | des_decrypt_xdmauth(auth->fakedata+9, data, 24); |
| 189 | if (memcmp(auth->fakedata, data, 8) != 0) |
| 190 | return "XDM-AUTHORIZATION-1 data failed check"; /* cookie wrong */ |
| 191 | if (GET_32BIT_MSB_FIRST(data+8) != peer_ip) |
| 192 | return "XDM-AUTHORIZATION-1 data failed check"; /* IP wrong */ |
| 193 | if ((int)GET_16BIT_MSB_FIRST(data+12) != peer_port) |
| 194 | return "XDM-AUTHORIZATION-1 data failed check"; /* port wrong */ |
| 195 | t = GET_32BIT_MSB_FIRST(data+14); |
| 196 | for (i = 18; i < 24; i++) |
| 197 | if (data[i] != 0) /* zero padding wrong */ |
| 198 | return "XDM-AUTHORIZATION-1 data failed check"; |
| 199 | tim = time(NULL); |
| 200 | if (abs(t - tim) > XDM_MAXSKEW) |
| 201 | return "XDM-AUTHORIZATION-1 time stamp was too far out"; |
| 202 | seen = snew(struct XDMSeen); |
| 203 | seen->time = t; |
| 204 | memcpy(seen->clientid, data+8, 6); |
| 205 | assert(auth->xdmseen != NULL); |
| 206 | ret = add234(auth->xdmseen, seen); |
| 207 | if (ret != seen) { |
| 208 | sfree(seen); |
| 209 | return "XDM-AUTHORIZATION-1 data replayed"; |
| 210 | } |
| 211 | /* While we're here, purge entries too old to be replayed. */ |
| 212 | for (;;) { |
| 213 | seen = index234(auth->xdmseen, 0); |
| 214 | assert(seen != NULL); |
| 215 | if (t - seen->time <= XDM_MAXSKEW) |
| 216 | break; |
| 217 | sfree(delpos234(auth->xdmseen, 0)); |
| 218 | } |
| 219 | } |
| 220 | /* implement other protocols here if ever required */ |
| 221 | return NULL; |
| 222 | } |
| 223 | |
| 224 | static void x11_log(Plug p, int type, SockAddr addr, int port, |
| 225 | const char *error_msg, int error_code) |
| 226 | { |
| 227 | /* We have no interface to the logging module here, so we drop these. */ |
| 228 | } |
| 229 | |
| 230 | static int x11_closing(Plug plug, const char *error_msg, int error_code, |
| 231 | int calling_back) |
| 232 | { |
| 233 | struct X11Private *pr = (struct X11Private *) plug; |
| 234 | |
| 235 | /* |
| 236 | * We have no way to communicate down the forwarded connection, |
| 237 | * so if an error occurred on the socket, we just ignore it |
| 238 | * and treat it like a proper close. |
| 239 | */ |
| 240 | sshfwd_close(pr->c); |
| 241 | x11_close(pr->s); |
| 242 | return 1; |
| 243 | } |
| 244 | |
| 245 | static int x11_receive(Plug plug, int urgent, char *data, int len) |
| 246 | { |
| 247 | struct X11Private *pr = (struct X11Private *) plug; |
| 248 | |
| 249 | if (sshfwd_write(pr->c, data, len) > 0) { |
| 250 | pr->throttled = 1; |
| 251 | sk_set_frozen(pr->s, 1); |
| 252 | } |
| 253 | |
| 254 | return 1; |
| 255 | } |
| 256 | |
| 257 | static void x11_sent(Plug plug, int bufsize) |
| 258 | { |
| 259 | struct X11Private *pr = (struct X11Private *) plug; |
| 260 | |
| 261 | sshfwd_unthrottle(pr->c, bufsize); |
| 262 | } |
| 263 | |
| 264 | /* |
| 265 | * When setting up X forwarding, we should send the screen number |
| 266 | * from the specified local display. This function extracts it from |
| 267 | * the display string. |
| 268 | */ |
| 269 | int x11_get_screen_number(char *display) |
| 270 | { |
| 271 | int n; |
| 272 | |
| 273 | n = strcspn(display, ":"); |
| 274 | if (!display[n]) |
| 275 | return 0; |
| 276 | n = strcspn(display, "."); |
| 277 | if (!display[n]) |
| 278 | return 0; |
| 279 | return atoi(display + n + 1); |
| 280 | } |
| 281 | |
| 282 | /* Find the right display, returns an allocated string */ |
| 283 | char *x11_display(const char *display) { |
| 284 | char *ret; |
| 285 | if(!display || !*display) { |
| 286 | /* try to find platform-specific local display */ |
| 287 | if((ret = platform_get_x_display())==0) |
| 288 | /* plausible default for all platforms */ |
| 289 | ret = dupstr(":0"); |
| 290 | } else |
| 291 | ret = dupstr(display); |
| 292 | if(ret[0] == ':') { |
| 293 | /* no transport specified, use whatever we think is best */ |
| 294 | char *s = dupcat(platform_x11_best_transport, ret, (char *)0); |
| 295 | sfree(ret); |
| 296 | return s; |
| 297 | } else |
| 298 | return ret; |
| 299 | } |
| 300 | |
| 301 | /* |
| 302 | * Called to set up the raw connection. |
| 303 | * |
| 304 | * Returns an error message, or NULL on success. |
| 305 | * also, fills the SocketsStructure |
| 306 | */ |
| 307 | const char *x11_init(Socket * s, char *display, void *c, void *auth, |
| 308 | const char *peeraddr, int peerport, const Config *cfg) |
| 309 | { |
| 310 | static const struct plug_function_table fn_table = { |
| 311 | x11_log, |
| 312 | x11_closing, |
| 313 | x11_receive, |
| 314 | x11_sent, |
| 315 | NULL |
| 316 | }; |
| 317 | |
| 318 | SockAddr addr; |
| 319 | int port; |
| 320 | const char *err; |
| 321 | char *dummy_realhost; |
| 322 | char host[128]; |
| 323 | int n, displaynum; |
| 324 | struct X11Private *pr; |
| 325 | |
| 326 | /* default display */ |
| 327 | display = x11_display(display); |
| 328 | /* |
| 329 | * Split up display name into host and display-number parts. |
| 330 | */ |
| 331 | n = strcspn(display, ":"); |
| 332 | assert(n != 0); /* x11_display() promises this */ |
| 333 | if (display[n]) |
| 334 | displaynum = atoi(display + n + 1); |
| 335 | else |
| 336 | displaynum = 0; /* sensible default */ |
| 337 | if (n > sizeof(host) - 1) |
| 338 | n = sizeof(host) - 1; |
| 339 | strncpy(host, display, n); |
| 340 | host[n] = '\0'; |
| 341 | sfree(display); |
| 342 | |
| 343 | if(!strcmp(host, "unix")) { |
| 344 | /* use AF_UNIX sockets (doesn't make sense on all platforms) */ |
| 345 | addr = platform_get_x11_unix_address(displaynum, |
| 346 | &dummy_realhost); |
| 347 | port = 0; /* to show we are not confused */ |
| 348 | } else { |
| 349 | port = 6000 + displaynum; |
| 350 | |
| 351 | /* |
| 352 | * Try to find host. |
| 353 | */ |
| 354 | addr = name_lookup(host, port, &dummy_realhost, cfg, ADDRTYPE_UNSPEC); |
| 355 | if ((err = sk_addr_error(addr)) != NULL) { |
| 356 | sk_addr_free(addr); |
| 357 | return err; |
| 358 | } |
| 359 | } |
| 360 | |
| 361 | /* |
| 362 | * Open socket. |
| 363 | */ |
| 364 | pr = snew(struct X11Private); |
| 365 | pr->fn = &fn_table; |
| 366 | pr->auth_protocol = NULL; |
| 367 | pr->auth = (struct X11Auth *)auth; |
| 368 | pr->verified = 0; |
| 369 | pr->data_read = 0; |
| 370 | pr->throttled = pr->throttle_override = 0; |
| 371 | pr->c = c; |
| 372 | |
| 373 | pr->s = *s = new_connection(addr, dummy_realhost, port, |
| 374 | 0, 1, 0, 0, (Plug) pr, cfg); |
| 375 | if ((err = sk_socket_error(*s)) != NULL) { |
| 376 | sfree(pr); |
| 377 | return err; |
| 378 | } |
| 379 | |
| 380 | /* |
| 381 | * See if we can make sense of the peer address we were given. |
| 382 | */ |
| 383 | { |
| 384 | int i[4]; |
| 385 | if (peeraddr && |
| 386 | 4 == sscanf(peeraddr, "%d.%d.%d.%d", i+0, i+1, i+2, i+3)) { |
| 387 | pr->peer_ip = (i[0] << 24) | (i[1] << 16) | (i[2] << 8) | i[3]; |
| 388 | pr->peer_port = peerport; |
| 389 | } else { |
| 390 | pr->peer_ip = 0; |
| 391 | pr->peer_port = -1; |
| 392 | } |
| 393 | } |
| 394 | |
| 395 | sk_set_private_ptr(*s, pr); |
| 396 | return NULL; |
| 397 | } |
| 398 | |
| 399 | void x11_close(Socket s) |
| 400 | { |
| 401 | struct X11Private *pr; |
| 402 | if (!s) |
| 403 | return; |
| 404 | pr = (struct X11Private *) sk_get_private_ptr(s); |
| 405 | if (pr->auth_protocol) { |
| 406 | sfree(pr->auth_protocol); |
| 407 | sfree(pr->auth_data); |
| 408 | } |
| 409 | |
| 410 | sfree(pr); |
| 411 | |
| 412 | sk_close(s); |
| 413 | } |
| 414 | |
| 415 | void x11_unthrottle(Socket s) |
| 416 | { |
| 417 | struct X11Private *pr; |
| 418 | if (!s) |
| 419 | return; |
| 420 | pr = (struct X11Private *) sk_get_private_ptr(s); |
| 421 | |
| 422 | pr->throttled = 0; |
| 423 | sk_set_frozen(s, pr->throttled || pr->throttle_override); |
| 424 | } |
| 425 | |
| 426 | void x11_override_throttle(Socket s, int enable) |
| 427 | { |
| 428 | struct X11Private *pr; |
| 429 | if (!s) |
| 430 | return; |
| 431 | pr = (struct X11Private *) sk_get_private_ptr(s); |
| 432 | |
| 433 | pr->throttle_override = enable; |
| 434 | sk_set_frozen(s, pr->throttled || pr->throttle_override); |
| 435 | } |
| 436 | |
| 437 | /* |
| 438 | * Called to send data down the raw connection. |
| 439 | */ |
| 440 | int x11_send(Socket s, char *data, int len) |
| 441 | { |
| 442 | struct X11Private *pr; |
| 443 | if (!s) |
| 444 | return 0; |
| 445 | pr = (struct X11Private *) sk_get_private_ptr(s); |
| 446 | |
| 447 | /* |
| 448 | * Read the first packet. |
| 449 | */ |
| 450 | while (len > 0 && pr->data_read < 12) |
| 451 | pr->firstpkt[pr->data_read++] = (unsigned char) (len--, *data++); |
| 452 | if (pr->data_read < 12) |
| 453 | return 0; |
| 454 | |
| 455 | /* |
| 456 | * If we have not allocated the auth_protocol and auth_data |
| 457 | * strings, do so now. |
| 458 | */ |
| 459 | if (!pr->auth_protocol) { |
| 460 | pr->auth_plen = GET_16BIT(pr->firstpkt[0], pr->firstpkt + 6); |
| 461 | pr->auth_dlen = GET_16BIT(pr->firstpkt[0], pr->firstpkt + 8); |
| 462 | pr->auth_psize = (pr->auth_plen + 3) & ~3; |
| 463 | pr->auth_dsize = (pr->auth_dlen + 3) & ~3; |
| 464 | /* Leave room for a terminating zero, to make our lives easier. */ |
| 465 | pr->auth_protocol = snewn(pr->auth_psize + 1, char); |
| 466 | pr->auth_data = snewn(pr->auth_dsize, unsigned char); |
| 467 | } |
| 468 | |
| 469 | /* |
| 470 | * Read the auth_protocol and auth_data strings. |
| 471 | */ |
| 472 | while (len > 0 && pr->data_read < 12 + pr->auth_psize) |
| 473 | pr->auth_protocol[pr->data_read++ - 12] = (len--, *data++); |
| 474 | while (len > 0 && pr->data_read < 12 + pr->auth_psize + pr->auth_dsize) |
| 475 | pr->auth_data[pr->data_read++ - 12 - |
| 476 | pr->auth_psize] = (unsigned char) (len--, *data++); |
| 477 | if (pr->data_read < 12 + pr->auth_psize + pr->auth_dsize) |
| 478 | return 0; |
| 479 | |
| 480 | /* |
| 481 | * If we haven't verified the authentication, do so now. |
| 482 | */ |
| 483 | if (!pr->verified) { |
| 484 | char *err; |
| 485 | |
| 486 | pr->auth_protocol[pr->auth_plen] = '\0'; /* ASCIZ */ |
| 487 | err = x11_verify(pr->peer_ip, pr->peer_port, |
| 488 | pr->auth, pr->auth_protocol, |
| 489 | pr->auth_data, pr->auth_dlen); |
| 490 | |
| 491 | /* |
| 492 | * If authentication failed, construct and send an error |
| 493 | * packet, then terminate the connection. |
| 494 | */ |
| 495 | if (err) { |
| 496 | char *message; |
| 497 | int msglen, msgsize; |
| 498 | unsigned char *reply; |
| 499 | |
| 500 | message = dupprintf("PuTTY X11 proxy: %s", err); |
| 501 | msglen = strlen(message); |
| 502 | reply = snewn(8 + msglen+1 + 4, unsigned char); /* include zero */ |
| 503 | msgsize = (msglen + 3) & ~3; |
| 504 | reply[0] = 0; /* failure */ |
| 505 | reply[1] = msglen; /* length of reason string */ |
| 506 | memcpy(reply + 2, pr->firstpkt + 2, 4); /* major/minor proto vsn */ |
| 507 | PUT_16BIT(pr->firstpkt[0], reply + 6, msgsize >> 2);/* data len */ |
| 508 | memset(reply + 8, 0, msgsize); |
| 509 | memcpy(reply + 8, message, msglen); |
| 510 | sshfwd_write(pr->c, (char *)reply, 8 + msgsize); |
| 511 | sshfwd_close(pr->c); |
| 512 | x11_close(s); |
| 513 | sfree(reply); |
| 514 | sfree(message); |
| 515 | return 0; |
| 516 | } |
| 517 | |
| 518 | /* |
| 519 | * Now we know we're going to accept the connection. Strip |
| 520 | * the fake auth data, and optionally put real auth data in |
| 521 | * instead. |
| 522 | */ |
| 523 | { |
| 524 | char realauthdata[64]; |
| 525 | int realauthlen = 0; |
| 526 | int authstrlen = strlen(x11_authnames[pr->auth->realproto]); |
| 527 | int buflen; |
| 528 | static const char zeroes[4] = { 0,0,0,0 }; |
| 529 | void *buf; |
| 530 | |
| 531 | if (pr->auth->realproto == X11_MIT) { |
| 532 | assert(pr->auth->reallen <= lenof(realauthdata)); |
| 533 | realauthlen = pr->auth->reallen; |
| 534 | memcpy(realauthdata, pr->auth->realdata, realauthlen); |
| 535 | } else if (pr->auth->realproto == X11_XDM && |
| 536 | pr->auth->reallen == 16 && |
| 537 | ((buf = sk_getxdmdata(s, &buflen))!=0)) { |
| 538 | time_t t; |
| 539 | realauthlen = (buflen+12+7) & ~7; |
| 540 | assert(realauthlen <= lenof(realauthdata)); |
| 541 | memset(realauthdata, 0, realauthlen); |
| 542 | memcpy(realauthdata, pr->auth->realdata, 8); |
| 543 | memcpy(realauthdata+8, buf, buflen); |
| 544 | t = time(NULL); |
| 545 | PUT_32BIT_MSB_FIRST(realauthdata+8+buflen, t); |
| 546 | des_encrypt_xdmauth(pr->auth->realdata+9, |
| 547 | (unsigned char *)realauthdata, |
| 548 | realauthlen); |
| 549 | sfree(buf); |
| 550 | } |
| 551 | /* implement other auth methods here if required */ |
| 552 | |
| 553 | PUT_16BIT(pr->firstpkt[0], pr->firstpkt + 6, authstrlen); |
| 554 | PUT_16BIT(pr->firstpkt[0], pr->firstpkt + 8, realauthlen); |
| 555 | |
| 556 | sk_write(s, (char *)pr->firstpkt, 12); |
| 557 | |
| 558 | if (authstrlen) { |
| 559 | sk_write(s, x11_authnames[pr->auth->realproto], authstrlen); |
| 560 | sk_write(s, zeroes, 3 & (-authstrlen)); |
| 561 | } |
| 562 | if (realauthlen) { |
| 563 | sk_write(s, realauthdata, realauthlen); |
| 564 | sk_write(s, zeroes, 3 & (-realauthlen)); |
| 565 | } |
| 566 | } |
| 567 | pr->verified = 1; |
| 568 | } |
| 569 | |
| 570 | /* |
| 571 | * After initialisation, just copy data simply. |
| 572 | */ |
| 573 | |
| 574 | return sk_write(s, data, len); |
| 575 | } |