* Uncompress a packet of total length total_len. The first buflen * bytes are at buf; this must include the entire (compressed or * uncompressed) TCP/IP header. This procedure returns the length * of the VJ header, with a pointer to the uncompressed IP header * in *hdrp and its length in *hlenp. */
| 450 | * in *hdrp and its length in *hlenp. |
| 451 | */ |
| 452 | int |
| 453 | sl_uncompress_tcp_core(u_char *buf, int buflen, int total_len, u_int type, |
| 454 | struct slcompress *comp, u_char **hdrp, u_int *hlenp) |
| 455 | { |
| 456 | u_char *cp; |
| 457 | u_int hlen, changes; |
| 458 | struct tcphdr *th; |
| 459 | struct cstate *cs; |
| 460 | struct ip *ip; |
| 461 | u_int16_t *bp; |
| 462 | u_int vjlen; |
| 463 | |
| 464 | switch (type) { |
| 465 | case TYPE_UNCOMPRESSED_TCP: |
| 466 | ip = (struct ip *) buf; |
| 467 | if (ip->ip_p >= MAX_STATES) |
| 468 | goto bad; |
| 469 | cs = &comp->rstate[comp->last_recv = ip->ip_p]; |
| 470 | comp->flags &=~ SLF_TOSS; |
| 471 | ip->ip_p = IPPROTO_TCP; |
| 472 | /* |
| 473 | * Calculate the size of the TCP/IP header and make sure that |
| 474 | * we don't overflow the space we have available for it. |
| 475 | */ |
| 476 | hlen = ip->ip_hl << 2; |
| 477 | if (hlen + sizeof(struct tcphdr) > buflen) |
| 478 | goto bad; |
| 479 | hlen += ((struct tcphdr *)&((char *)ip)[hlen])->th_off << 2; |
| 480 | if (hlen > MAX_HDR || hlen > buflen) |
| 481 | goto bad; |
| 482 | BCOPY(ip, &cs->cs_ip, hlen); |
| 483 | cs->cs_hlen = hlen; |
| 484 | INCR(sls_uncompressedin) |
| 485 | *hdrp = (u_char *) &cs->cs_ip; |
| 486 | *hlenp = hlen; |
| 487 | return (0); |
| 488 | |
| 489 | default: |
| 490 | goto bad; |
| 491 | |
| 492 | case TYPE_COMPRESSED_TCP: |
| 493 | break; |
| 494 | } |
| 495 | /* We've got a compressed packet. */ |
| 496 | INCR(sls_compressedin) |
| 497 | cp = buf; |
| 498 | changes = *cp++; |
| 499 | if (changes & NEW_C) { |
| 500 | /* Make sure the state index is in range, then grab the state. |
| 501 | * If we have a good state index, clear the 'discard' flag. */ |
| 502 | if (*cp >= MAX_STATES) |
| 503 | goto bad; |
| 504 | |
| 505 | comp->flags &=~ SLF_TOSS; |
| 506 | comp->last_recv = *cp++; |
| 507 | } else { |
| 508 | /* this packet has an implicit state index. If we've |
| 509 | * had a line error since the last time we got an |
no outgoing calls
no test coverage detected