Method decodeType_common

Server/src/bgp/ExtCommunity.cpp:136–291

* Decode common Type/Subtypes * * \details * Decodes the common 2-octet, 4-octet, and IPv4 specific common subtypes. * Converts to human readable form. * * \param [in] ec_hdr Reference to the extended community header * \param [in] isGlobal4Bytes True if the global admin field is 4 bytes, false if 2 * \param [in] isGlobalIPv4 Tru

     * \return  Decoded string value
     */
    std::string ExtCommunity::decodeType_common(const extcomm_hdr &ec_hdr, bool isGlobal4Bytes, bool isGlobalIPv4) {
        std::stringstream   val_ss;
        uint16_t            val_16b;
        uint32_t            val_32b;
        char                ipv4_char[16] = {0};

        /*
         * Decode values based on bit size
         */
        if (isGlobal4Bytes) {
            // Four-byte global field
            memcpy(&val_32b, ec_hdr.value, 4);
            memcpy(&val_16b, ec_hdr.value + 4, 2);

            bgp::SWAP_BYTES(&val_16b);

            if (isGlobalIPv4) {
                inet_ntop(AF_INET, &val_32b, ipv4_char, sizeof(ipv4_char));
            } else
                bgp::SWAP_BYTES(&val_32b);

        } else {
            // Two-byte global field
            memcpy(&val_16b, ec_hdr.value, 2);
            memcpy(&val_32b, ec_hdr.value + 2, 4);

            // Chagne to host order
            bgp::SWAP_BYTES(&val_16b);
            bgp::SWAP_BYTES(&val_32b);
        }

        /*
         * Decode by subtype
         */
        switch (ec_hdr.low_type) {

            case EXT_COMMON_BGP_DATA_COL :
                if (isGlobal4Bytes)
                    val_ss << "colc=" << val_32b << ":" << val_16b;

                else
                    val_ss << "colc=" << val_16b << ":" << val_32b;

                break;

            case EXT_COMMON_ROUTE_ORIGIN :
                if (isGlobalIPv4)
                    val_ss << "soo=" << ipv4_char << ":" << val_16b;

                else if (isGlobal4Bytes)
                    val_ss << "soo=" << val_32b << ":" << val_16b;

                else
                    val_ss << "soo=" << val_16b << ":" << val_32b;
                break;

            case EXT_COMMON_ROUTE_TARGET :
                if (isGlobalIPv4)