pintos-os.org Git - openvswitch/blob - datapath/linux/compat/exthdrs_core.c

   1 #include <linux/ipv6.h>
   2 #include <net/ipv6.h>
   3
   4 /* This function is upstream but not the version which supplies the
   5  * fragment offset.  We plan to propose the extended version.
   6  */
   7 int rpl_ipv6_skip_exthdr(const struct sk_buff *skb, int start,
   8                          u8 *nexthdrp, __be16 *frag_offp)
   9 {
  10         u8 nexthdr = *nexthdrp;
  11
  12         *frag_offp = 0;
  13
  14         while (ipv6_ext_hdr(nexthdr)) {
  15                 struct ipv6_opt_hdr _hdr, *hp;
  16                 int hdrlen;
  17
  18                 if (nexthdr == NEXTHDR_NONE)
  19                         return -1;
  20                 hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr);
  21                 if (hp == NULL)
  22                         return -1;
  23                 if (nexthdr == NEXTHDR_FRAGMENT) {
  24                         __be16 _frag_off, *fp;
  25                         fp = skb_header_pointer(skb,
  26                                                 start+offsetof(struct frag_hdr,
  27                                                                frag_off),
  28                                                 sizeof(_frag_off),
  29                                                 &_frag_off);
  30                         if (fp == NULL)
  31                                 return -1;
  32
  33                         *frag_offp = *fp;
  34                         if (ntohs(*frag_offp) & ~0x7)
  35                                 break;
  36                         hdrlen = 8;
  37                 } else if (nexthdr == NEXTHDR_AUTH)
  38                         hdrlen = (hp->hdrlen+2)<<2;
  39                 else
  40                         hdrlen = ipv6_optlen(hp);
  41
  42                 nexthdr = hp->nexthdr;
  43                 start += hdrlen;
  44         }
  45
  46         *nexthdrp = nexthdr;
  47         return start;
  48 }