- unsigned int hdrlen = 0;
-
- /* type of the 1st exthdr */
- nexthdr = skb->nh.ipv6h->nexthdr;
- /* pointer to the 1st exthdr */
- ptr = sizeof(struct ipv6hdr);
- /* available length */
- len = skb->len - ptr;
- temp = 0;
-
- while (ip6t_ext_hdr(nexthdr)) {
- struct ipv6_opt_hdr _hdr, *hp;
-
- DEBUGP("ipv6_frag header iteration \n");
-
- /* Is there enough space for the next ext header? */
- if (len < (int)sizeof(struct ipv6_opt_hdr))
- return 0;
- /* No more exthdr -> evaluate */
- if (nexthdr == NEXTHDR_NONE) {
- break;
- }
- /* ESP -> evaluate */
- if (nexthdr == NEXTHDR_ESP) {
- break;
- }
-
- hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr);
- BUG_ON(hp == NULL);
-
- /* Calculate the header length */
- if (nexthdr == NEXTHDR_FRAGMENT) {
- hdrlen = 8;
- } else if (nexthdr == NEXTHDR_AUTH)
- hdrlen = (hp->hdrlen+2)<<2;
- else
- hdrlen = ipv6_optlen(hp);
-
- /* FRAG -> evaluate */
- if (nexthdr == NEXTHDR_FRAGMENT) {
- temp |= MASK_FRAGMENT;
- break;
- }
-
-
- /* set the flag */
- switch (nexthdr){
- case NEXTHDR_HOP:
- case NEXTHDR_ROUTING:
- case NEXTHDR_FRAGMENT:
- case NEXTHDR_AUTH:
- case NEXTHDR_DEST:
- break;
- default:
- DEBUGP("ipv6_frag match: unknown nextheader %u\n",nexthdr);
- return 0;
- break;
- }
-
- nexthdr = hp->nexthdr;
- len -= hdrlen;
- ptr += hdrlen;
- if ( ptr > skb->len ) {
- DEBUGP("ipv6_frag: new pointer too large! \n");
- break;
- }
- }
-
- /* FRAG header not found */
- if ( temp != MASK_FRAGMENT ) return 0;
-
- if (len < sizeof(struct frag_hdr)){
- *hotdrop = 1;
- return 0;
- }