congestvpn/ip_header.cpp

#include <cstring>

#include "ip_header.hpp"
#include "util.hpp"

bool parse_ipv6_header(const char* data, size_t len, IPv6Header& header) {
    if(len < 40) { // header too short
        kdebugf("Bad v6 header -- too short.\n");
        return false;
    }
    if((data[0] & 0xf0) != 0x60) { // bad version number
        kdebugf("Bad v6 header -- bad version number (byte = %x).\n", data[0]);
        return false;
    }

    memcpy(&(header.source), data + 8, 16);
    memcpy(&(header.dest), data + 24, 16);
    header.payload_length = ntohs(*(uint16_t*)(data + 4));
    return true;
}