print-ldp.c

来自「TCPDUMP的C语言源代码,是在数据链路层的应用」· C语言 代码 · 共 624 行 · 第 1/2 页

		tptr+=sizeof(struct in6_addr);                
	    }
            break;
#endif
        default:
            /* unknown AF */
            break;
        }
	break;

    case LDP_TLV_COMMON_SESSION:
	printf("\n\t      Version: %u, Keepalive: %us, Flags: [Downstream %s, Loop Detection %s]",
	       EXTRACT_16BITS(tptr), EXTRACT_16BITS(tptr+2),
	       (EXTRACT_16BITS(tptr+6)&0x8000) ? "On Demand" : "Unsolicited",
	       (EXTRACT_16BITS(tptr+6)&0x4000) ? "Enabled" : "Disabled"
	       );
	break;

    case LDP_TLV_FEC:
        fec_type = *tptr;
	printf("\n\t      %s FEC (0x%02x)",
	       tok2str(ldp_fec_values, "Unknown", fec_type),
	       fec_type);

	tptr+=1;
	switch(fec_type) {

	case LDP_FEC_WILDCARD:
	    break;
	case LDP_FEC_PREFIX:
	    af = EXTRACT_16BITS(tptr);
	    tptr+=2;
	    if (af == AFNUM_INET) {
		i=decode_prefix4(tptr,buf,sizeof(buf));
		printf(": IPv4 prefix %s",buf);
	    }
#ifdef INET6
	    else if (af == AFNUM_INET6) {
		i=decode_prefix6(tptr,buf,sizeof(buf));
		printf(": IPv6 prefix %s",buf);
	    }
#endif
	    break;
	case LDP_FEC_HOSTADDRESS:
	    break;
	case LDP_FEC_MARTINI_VC:
            if (!TTEST2(*tptr, 11))
                goto trunc;
            vc_info_len = *(tptr+2);

	    printf(": %s, %scontrol word, group-ID %u, VC-ID %u, VC-info-length: %u",
		   tok2str(l2vpn_encaps_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
		   EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
                   EXTRACT_32BITS(tptr+3),
		   EXTRACT_32BITS(tptr+7),
                   vc_info_len);

            if (vc_info_len == 0) /* infinite loop protection */
                break;

            tptr+=11;
            if (!TTEST2(*tptr, vc_info_len))
                goto trunc;

            while (vc_info_len > 2) {
                vc_info_tlv_type = *tptr;
                vc_info_tlv_len = *(tptr+1);
                if (vc_info_tlv_len < 2)
                    break;
                if (vc_info_len < vc_info_tlv_len)
                    break;

                printf("\n\t\tInterface Parameter: %s (0x%02x), len %u",
                       tok2str(ldp_fec_martini_ifparm_values,"Unknown",vc_info_tlv_type),
                       vc_info_tlv_type,
                       vc_info_tlv_len);

                switch(vc_info_tlv_type) {
                case LDP_FEC_MARTINI_IFPARM_MTU:
                    printf(": %u",EXTRACT_16BITS(tptr+2));
                    break;

                case LDP_FEC_MARTINI_IFPARM_DESC:
                    printf(": ");
                    for (idx = 2; idx < vc_info_tlv_len; idx++)
                        safeputchar(*(tptr+idx));
                    break;

                case LDP_FEC_MARTINI_IFPARM_VCCV:
                    printf("\n\t\t  Control Channels (0x%02x) = [%s]",
                           *(tptr+2),
                           bittok2str(ldp_fec_martini_ifparm_vccv_cc_values,"none",*(tptr+2)));
                    printf("\n\t\t  CV Types (0x%02x) = [%s]",
                           *(tptr+3),
                           bittok2str(ldp_fec_martini_ifparm_vccv_cv_values,"none",*(tptr+3)));
                    break;

                default:
                    print_unknown_data(tptr+2,"\n\t\t  ",vc_info_tlv_len-2);
                    break;
                }

                vc_info_len -= vc_info_tlv_len;
                tptr += vc_info_tlv_len;
            }
	    break;
	}

	break;

    case LDP_TLV_GENERIC_LABEL:
	printf("\n\t      Label: %u", EXTRACT_32BITS(tptr) & 0xfffff);
	break;

    case LDP_TLV_STATUS:
	ui = EXTRACT_32BITS(tptr);
	tptr+=4;
	printf("\n\t      Status: 0x%02x, Flags: [%s and %s forward]",
	       ui&0x3fffffff,
	       ui&0x80000000 ? "Fatal error" : "Advisory Notification",
	       ui&0x40000000 ? "do" : "don't");
	ui = EXTRACT_32BITS(tptr);
	tptr+=4;
	if (ui)
	    printf(", causing Message ID: 0x%08x", ui);
	break;

    case LDP_TLV_FT_SESSION:
	ft_flags = EXTRACT_16BITS(tptr);
	printf("\n\t      Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
	       ft_flags&0x8000 ? "" : "No ",
	       ft_flags&0x8 ? "" : "Don't ",
	       ft_flags&0x4 ? "" : "No ",
	       ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
	       ft_flags&0x1 ? "" : "Don't ");
	tptr+=4;
	ui = EXTRACT_32BITS(tptr);
	if (ui)
	    printf(", Reconnect Timeout: %ums", ui);
	tptr+=4;
	ui = EXTRACT_32BITS(tptr);
	if (ui)
	    printf(", Recovery Time: %ums", ui);
	break;

    case LDP_TLV_MTU:
	printf("\n\t      MTU: %u", EXTRACT_16BITS(tptr));
	break;


    /*
     *  FIXME those are the defined TLVs that lack a decoder
     *  you are welcome to contribute code ;-)
     */

    case LDP_TLV_HOP_COUNT:
    case LDP_TLV_PATH_VECTOR:
    case LDP_TLV_ATM_LABEL:
    case LDP_TLV_FR_LABEL:
    case LDP_TLV_EXTD_STATUS:
    case LDP_TLV_RETURNED_PDU:
    case LDP_TLV_RETURNED_MSG:
    case LDP_TLV_ATM_SESSION_PARM:
    case LDP_TLV_FR_SESSION_PARM:
    case LDP_TLV_LABEL_REQUEST_MSG_ID:

    default:
        if (vflag <= 1)
            print_unknown_data(tptr,"\n\t      ",tlv_tlen);
        break;
    }
    return(tlv_len+4); /* Type & Length fields not included */
 
trunc:
    printf("\n\t\t packet exceeded snapshot");
    return 0;
}

void
ldp_print(register const u_char *pptr, register u_int len) {

    int processed;
    while (len > (sizeof(struct ldp_common_header) + sizeof(struct ldp_msg_header))) {
        processed = ldp_msg_print(pptr);
        if (processed == 0)
            return;
        len -= processed;
        pptr += processed;
    }
}


int
ldp_msg_print(register const u_char *pptr) {

    const struct ldp_common_header *ldp_com_header;
    const struct ldp_msg_header *ldp_msg_header;
    const u_char *tptr,*msg_tptr;
    u_short tlen;
    u_short pdu_len,msg_len,msg_type,msg_tlen;
    int hexdump,processed;

    tptr=pptr;
    ldp_com_header = (const struct ldp_common_header *)pptr;
    TCHECK(*ldp_com_header);

    /*
     * Sanity checking of the header.
     */
    if (EXTRACT_16BITS(&ldp_com_header->version) != LDP_VERSION) {
	printf("%sLDP version %u packet not supported",
               (vflag < 1) ? "" : "\n\t",
               EXTRACT_16BITS(&ldp_com_header->version));
	return 0;
    }

    /* print the LSR-ID, label-space & length */
    pdu_len = EXTRACT_16BITS(&ldp_com_header->pdu_length);
    printf("%sLDP, Label-Space-ID: %s:%u, pdu-length: %u",
           (vflag < 1) ? "" : "\n\t",
           ipaddr_string(&ldp_com_header->lsr_id),
           EXTRACT_16BITS(&ldp_com_header->label_space),
           pdu_len);

    /* bail out if non-verbose */ 
    if (vflag < 1)
        return 0;

    /* ok they seem to want to know everything - lets fully decode it */
    tlen=pdu_len;

    tptr += sizeof(const struct ldp_common_header);
    tlen -= sizeof(const struct ldp_common_header)-4;	/* Type & Length fields not included */

    while(tlen>0) {
        /* did we capture enough for fully decoding the msg header ? */
        if (!TTEST2(*tptr, sizeof(struct ldp_msg_header)))
            goto trunc;

        ldp_msg_header = (const struct ldp_msg_header *)tptr;
        msg_len=EXTRACT_16BITS(ldp_msg_header->length);
        msg_type=LDP_MASK_MSG_TYPE(EXTRACT_16BITS(ldp_msg_header->type));

        /* FIXME vendor private / experimental check */
        printf("\n\t  %s Message (0x%04x), length: %u, Message ID: 0x%08x, Flags: [%s if unknown]",
               tok2str(ldp_msg_values,
                       "Unknown",
                       msg_type),
               msg_type,
               msg_len,
               EXTRACT_32BITS(&ldp_msg_header->id),
               LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_msg_header->type)) ? "continue processing" : "ignore");

        if (msg_len == 0) /* infinite loop protection */
            return 0;

        msg_tptr=tptr+sizeof(struct ldp_msg_header);
        msg_tlen=msg_len-sizeof(struct ldp_msg_header)+4; /* Type & Length fields not included */

        /* did we capture enough for fully decoding the message ? */
        if (!TTEST2(*tptr, msg_len))
            goto trunc;
        hexdump=FALSE;

        switch(msg_type) {
 
        case LDP_MSG_NOTIF:
        case LDP_MSG_HELLO:
        case LDP_MSG_INIT:
        case LDP_MSG_KEEPALIVE:
        case LDP_MSG_ADDRESS:
        case LDP_MSG_LABEL_MAPPING:
        case LDP_MSG_ADDRESS_WITHDRAW:
        case LDP_MSG_LABEL_WITHDRAW:
            while(msg_tlen >= 4) {
                processed = ldp_tlv_print(msg_tptr);
                if (processed == 0)
                    break;
                msg_tlen-=processed;
                msg_tptr+=processed;
            }
            break;

        /*
         *  FIXME those are the defined messages that lack a decoder
         *  you are welcome to contribute code ;-)
         */

        case LDP_MSG_LABEL_REQUEST:
        case LDP_MSG_LABEL_RELEASE:
        case LDP_MSG_LABEL_ABORT_REQUEST:

        default:
            if (vflag <= 1)
                print_unknown_data(msg_tptr,"\n\t  ",msg_tlen);
            break;
        }
        /* do we want to see an additionally hexdump ? */
        if (vflag > 1 || hexdump==TRUE)
            print_unknown_data(tptr+sizeof(sizeof(struct ldp_msg_header)),"\n\t  ",
                               msg_len);

        tptr += msg_len+4;
        tlen -= msg_len+4;
    }
    return pdu_len+4;
trunc:
    printf("\n\t\t packet exceeded snapshot");
    return 0;
}