/* * in6_cksum_phdr: * * Compute significant parts of the IPv6 checksum pseudo-header * for use in a delayed TCP/UDP checksum calculation. * * Args: * * src Source IPv6 address * dst Destination IPv6 address * len htonl(proto-hdr-len) * nxt htonl(next-proto-number) * * NOTE: We expect the src and dst addresses to be 16-bit * aligned! */