C++ EXTRACT_16BITS函数代码示例

u_int
chdlc_print(netdissect_options *ndo, register const u_char *p, u_int length)
{
	u_int proto;
	const u_char *bp = p;

	if (length < CHDLC_HDRLEN)
		goto trunc;
	ND_TCHECK2(*p, CHDLC_HDRLEN);
	proto = EXTRACT_16BITS(&p[2]);
	if (ndo->ndo_eflag) {
                ND_PRINT((ndo, "%s, ethertype %s (0x%04x), length %u: ",
                       tok2str(chdlc_cast_values, "0x%02x", p[0]),
                       tok2str(ethertype_values, "Unknown", proto),
                       proto,
                       length));
	}

	length -= CHDLC_HDRLEN;
	p += CHDLC_HDRLEN;

	switch (proto) {
	case ETHERTYPE_IP:
		ip_print(ndo, p, length);
		break;
	case ETHERTYPE_IPV6:
		ip6_print(ndo, p, length);
		break;
	case CHDLC_TYPE_SLARP:
		chdlc_slarp_print(ndo, p, length);
		break;
#if 0
	case CHDLC_TYPE_CDP:
		chdlc_cdp_print(p, length);
		break;
#endif
        case ETHERTYPE_MPLS:
        case ETHERTYPE_MPLS_MULTI:
                mpls_print(ndo, p, length);
		break;
        case ETHERTYPE_ISO:
                /* is the fudge byte set ? lets verify by spotting ISO headers */
                if (length < 2)
                    goto trunc;
                ND_TCHECK_16BITS(p);
                if (*(p+1) == 0x81 ||
                    *(p+1) == 0x82 ||
                    *(p+1) == 0x83)
                    isoclns_print(ndo, p + 1, length - 1);
                else
                    isoclns_print(ndo, p, length);
                break;
	default:
                if (!ndo->ndo_eflag)
                        ND_PRINT((ndo, "unknown CHDLC protocol (0x%04x)", proto));
                break;
	}

	return (CHDLC_HDRLEN);

trunc:
	ND_PRINT((ndo, "[|chdlc]"));
	return ndo->ndo_snapend - bp;
}

static int dccp_print_option(netdissect_options *ndo, const u_char *option, u_int hlen)
{
	uint8_t optlen, i;

	ND_TCHECK(*option);

	if (*option >= 32) {
		ND_TCHECK(*(option+1));
		optlen = *(option +1);
		if (optlen < 2) {
			if (*option >= 128)
				ND_PRINT((ndo, "CCID option %u optlen too short", *option));
			else
				ND_PRINT((ndo, "%s optlen too short",
					  tok2str(dccp_option_values, "Option %u", *option)));
			return 0;
		}
	} else
		optlen = 1;

	if (hlen < optlen) {
		if (*option >= 128)
			ND_PRINT((ndo, "CCID option %u optlen goes past header length",
				  *option));
		else
			ND_PRINT((ndo, "%s optlen goes past header length",
				  tok2str(dccp_option_values, "Option %u", *option)));
		return 0;
	}
	ND_TCHECK2(*option, optlen);

	if (*option >= 128) {
		ND_PRINT((ndo, "CCID option %d", *option));
		switch (optlen) {
			case 4:
				ND_PRINT((ndo, " %u", EXTRACT_16BITS(option + 2)));
				break;
			case 6:
				ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2)));
				break;
			default:
				break;
		}
	} else {
		ND_PRINT((ndo, "%s", tok2str(dccp_option_values, "Option %u", *option)));
		switch (*option) {
		case 32:
		case 33:
		case 34:
		case 35:
			if (optlen < 3) {
				ND_PRINT((ndo, " optlen too short"));
				return optlen;
			}
			if (*(option + 2) < 10){
				ND_PRINT((ndo, " %s", dccp_feature_nums[*(option + 2)]));
				for (i = 0; i < optlen - 3; i++)
					ND_PRINT((ndo, " %d", *(option + 3 + i)));
			}
			break;
		case 36:
			if (optlen > 2) {
				ND_PRINT((ndo, " 0x"));
				for (i = 0; i < optlen - 2; i++)
					ND_PRINT((ndo, "%02x", *(option + 2 + i)));
			}
			break;
		case 37:
			for (i = 0; i < optlen - 2; i++)
				ND_PRINT((ndo, " %d", *(option + 2 + i)));
			break;
		case 38:
			if (optlen > 2) {
				ND_PRINT((ndo, " 0x"));
				for (i = 0; i < optlen - 2; i++)
					ND_PRINT((ndo, "%02x", *(option + 2 + i)));
			}
			break;
		case 39:
			if (optlen > 2) {
				ND_PRINT((ndo, " 0x"));
				for (i = 0; i < optlen - 2; i++)
					ND_PRINT((ndo, "%02x", *(option + 2 + i)));
			}
			break;
		case 40:
			if (optlen > 2) {
				ND_PRINT((ndo, " 0x"));
				for (i = 0; i < optlen - 2; i++)
					ND_PRINT((ndo, "%02x", *(option + 2 + i)));
			}
			break;
		case 41:
			if (optlen == 4)
				ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2)));
			else
				ND_PRINT((ndo, " optlen != 4"));
			break;
		case 42:
			if (optlen == 4)
//.........这里部分代码省略.........

u_int
token_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
{
	const struct token_header *trp;
	int llc_hdrlen;
	struct ether_header ehdr;
	u_int route_len = 0, hdr_len = TOKEN_HDRLEN;
	int seg;

	trp = (const struct token_header *)p;

	if (caplen < TOKEN_HDRLEN) {
		ND_PRINT((ndo, "%s", tstr));
		return hdr_len;
	}

	/*
	 * Get the TR addresses into a canonical form
	 */
	extract_token_addrs(trp, (char*)ESRC(&ehdr), (char*)EDST(&ehdr));

	/* Adjust for source routing information in the MAC header */
	if (IS_SOURCE_ROUTED(trp)) {
		/* Clear source-routed bit */
		*ESRC(&ehdr) &= 0x7f;

		if (ndo->ndo_eflag)
			token_hdr_print(ndo, trp, length, ESRC(&ehdr), EDST(&ehdr));

		if (caplen < TOKEN_HDRLEN + 2) {
			ND_PRINT((ndo, "%s", tstr));
			return hdr_len;
		}
		route_len = RIF_LENGTH(trp);
		hdr_len += route_len;
		if (caplen < hdr_len) {
			ND_PRINT((ndo, "%s", tstr));
			return hdr_len;
		}
		if (ndo->ndo_vflag) {
			ND_PRINT((ndo, "%s ", broadcast_indicator[BROADCAST(trp)]));
			ND_PRINT((ndo, "%s", direction[DIRECTION(trp)]));

			for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
				ND_PRINT((ndo, " [%d:%d]", RING_NUMBER(trp, seg),
				    BRIDGE_NUMBER(trp, seg)));
		} else {
			ND_PRINT((ndo, "rt = %x", EXTRACT_16BITS(&trp->token_rcf)));

			for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
				ND_PRINT((ndo, ":%x", EXTRACT_16BITS(&trp->token_rseg[seg])));
		}
		ND_PRINT((ndo, " (%s) ", largest_frame[LARGEST_FRAME(trp)]));
	} else {
		if (ndo->ndo_eflag)
			token_hdr_print(ndo, trp, length, ESRC(&ehdr), EDST(&ehdr));
	}

	/* Skip over token ring MAC header and routing information */
	length -= hdr_len;
	p += hdr_len;
	caplen -= hdr_len;

	/* Frame Control field determines interpretation of packet */
	if (FRAME_TYPE(trp) == TOKEN_FC_LLC) {
		/* Try to print the LLC-layer header & higher layers */
		llc_hdrlen = llc_print(ndo, p, length, caplen, ESRC(&ehdr),
		    EDST(&ehdr));
		if (llc_hdrlen < 0) {
			/* packet type not known, print raw packet */
			if (!ndo->ndo_suppress_default_print)
				ND_DEFAULTPRINT(p, caplen);
			llc_hdrlen = -llc_hdrlen;
		}
		hdr_len += llc_hdrlen;
	} else {
		/* Some kinds of TR packet we cannot handle intelligently */
		/* XXX - dissect MAC packets if frame type is 0 */
		if (!ndo->ndo_eflag)
			token_hdr_print(ndo, trp, length + TOKEN_HDRLEN + route_len,
			    ESRC(&ehdr), EDST(&ehdr));
		if (!ndo->ndo_suppress_default_print)
			ND_DEFAULTPRINT(p, caplen);
	}
	return (hdr_len);
}

static void
slow_oam_print(netdissect_options *ndo,
               register const u_char *tptr, register u_int tlen) {

    u_int hexdump;

    struct slow_oam_common_header_t {
        uint8_t flags[2];
        uint8_t code;
    };

    struct slow_oam_tlv_header_t {
        uint8_t type;
        uint8_t length;
    };

    union {
        const struct slow_oam_common_header_t *slow_oam_common_header;
        const struct slow_oam_tlv_header_t *slow_oam_tlv_header;
    } ptr;

    union {
	const struct slow_oam_info_t *slow_oam_info;
        const struct slow_oam_link_event_t *slow_oam_link_event;
        const struct slow_oam_variablerequest_t *slow_oam_variablerequest;
        const struct slow_oam_variableresponse_t *slow_oam_variableresponse;
        const struct slow_oam_loopbackctrl_t *slow_oam_loopbackctrl;
    } tlv;

    ptr.slow_oam_common_header = (struct slow_oam_common_header_t *)tptr;
    tptr += sizeof(struct slow_oam_common_header_t);
    tlen -= sizeof(struct slow_oam_common_header_t);

    ND_PRINT((ndo, "\n\tCode %s OAM PDU, Flags [%s]",
           tok2str(slow_oam_code_values, "Unknown (%u)", ptr.slow_oam_common_header->code),
           bittok2str(slow_oam_flag_values,
                      "none",
                      EXTRACT_16BITS(&ptr.slow_oam_common_header->flags))));

    switch (ptr.slow_oam_common_header->code) {
    case SLOW_OAM_CODE_INFO:
        while (tlen > 0) {
            ptr.slow_oam_tlv_header = (const struct slow_oam_tlv_header_t *)tptr;
            ND_PRINT((ndo, "\n\t  %s Information Type (%u), length %u",
                   tok2str(slow_oam_info_type_values, "Reserved",
                           ptr.slow_oam_tlv_header->type),
                   ptr.slow_oam_tlv_header->type,
                   ptr.slow_oam_tlv_header->length));

            hexdump = FALSE;
            switch (ptr.slow_oam_tlv_header->type) {
            case SLOW_OAM_INFO_TYPE_END_OF_TLV:
                if (ptr.slow_oam_tlv_header->length != 0) {
                    ND_PRINT((ndo, "\n\t    ERROR: illegal length - should be 0"));
                }
                return;

            case SLOW_OAM_INFO_TYPE_LOCAL: /* identical format - fall through */
            case SLOW_OAM_INFO_TYPE_REMOTE:
                tlv.slow_oam_info = (const struct slow_oam_info_t *)tptr;

                if (tlv.slow_oam_info->info_length !=
                    sizeof(struct slow_oam_info_t)) {
                    ND_PRINT((ndo, "\n\t    ERROR: illegal length - should be %lu",
                           (unsigned long) sizeof(struct slow_oam_info_t)));
                    return;
                }

                ND_PRINT((ndo, "\n\t    OAM-Version %u, Revision %u",
                       tlv.slow_oam_info->oam_version,
                       EXTRACT_16BITS(&tlv.slow_oam_info->revision)));

                ND_PRINT((ndo, "\n\t    State-Parser-Action %s, State-MUX-Action %s",
                       tok2str(slow_oam_info_type_state_parser_values, "Reserved",
                               tlv.slow_oam_info->state & OAM_INFO_TYPE_PARSER_MASK),
                       tok2str(slow_oam_info_type_state_mux_values, "Reserved",
                               tlv.slow_oam_info->state & OAM_INFO_TYPE_MUX_MASK)));
                ND_PRINT((ndo, "\n\t    OAM-Config Flags [%s], OAM-PDU-Config max-PDU size %u",
                       bittok2str(slow_oam_info_type_oam_config_values, "none",
                                  tlv.slow_oam_info->oam_config),
                       EXTRACT_16BITS(&tlv.slow_oam_info->oam_pdu_config) &
                       OAM_INFO_TYPE_PDU_SIZE_MASK));
                ND_PRINT((ndo, "\n\t    OUI %s (0x%06x), Vendor-Private 0x%08x",
                       tok2str(oui_values, "Unknown",
                               EXTRACT_24BITS(&tlv.slow_oam_info->oui)),
                       EXTRACT_24BITS(&tlv.slow_oam_info->oui),
                       EXTRACT_32BITS(&tlv.slow_oam_info->vendor_private)));
                break;

            case SLOW_OAM_INFO_TYPE_ORG_SPECIFIC:
                hexdump = TRUE;
                break;

            default:
                hexdump = TRUE;
                break;
            }

            /* infinite loop check */
            if (!ptr.slow_oam_tlv_header->length) {
//.........这里部分代码省略.........

static void
babel_print_v2(netdissect_options *ndo,
               const u_char *cp, u_int length) {
    u_int i;
    u_short bodylen;
    u_char v4_prefix[16] =
        {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 };
    u_char v6_prefix[16] = {0};

    ND_TCHECK2(*cp, 4);
    if (length < 4)
        goto corrupt;
    bodylen = EXTRACT_16BITS(cp + 2);
    ND_PRINT((ndo, " (%u)", bodylen));

    /* Process the TLVs in the body */
    i = 0;
    while(i < bodylen) {
        const u_char *message;
        u_int type, len;

        message = cp + 4 + i;

        ND_TCHECK2(*message, 1);
        if((type = message[0]) == MESSAGE_PAD1) {
            ND_PRINT((ndo, ndo->ndo_vflag ? "\n\tPad 1" : " pad1"));
            i += 1;
            continue;
        }

        ND_TCHECK2(*message, 2);
        ICHECK(i, 2);
        len = message[1];

        ND_TCHECK2(*message, 2 + len);
        ICHECK(i, 2 + len);

        switch(type) {
        case MESSAGE_PADN: {
            if (!ndo->ndo_vflag)
                ND_PRINT((ndo, " padN"));
            else
                ND_PRINT((ndo, "\n\tPad %d", len + 2));
        }
            break;

        case MESSAGE_ACK_REQ: {
            u_short nonce, interval;
            if (!ndo->ndo_vflag)
                ND_PRINT((ndo, " ack-req"));
            else {
                ND_PRINT((ndo, "\n\tAcknowledgment Request "));
                if(len < 6) goto corrupt;
                nonce = EXTRACT_16BITS(message + 4);
                interval = EXTRACT_16BITS(message + 6);
                ND_PRINT((ndo, "%04x %s", nonce, format_interval(interval)));
            }
        }
            break;

        case MESSAGE_ACK: {
            u_short nonce;
            if (!ndo->ndo_vflag)
                ND_PRINT((ndo, " ack"));
            else {
                ND_PRINT((ndo, "\n\tAcknowledgment "));
                if(len < 2) goto corrupt;
                nonce = EXTRACT_16BITS(message + 2);
                ND_PRINT((ndo, "%04x", nonce));
            }
        }
            break;

        case MESSAGE_HELLO:  {
            u_short seqno, interval;
            if (!ndo->ndo_vflag)
                ND_PRINT((ndo, " hello"));
            else {
                ND_PRINT((ndo, "\n\tHello "));
                if(len < 6) goto corrupt;
                seqno = EXTRACT_16BITS(message + 4);
                interval = EXTRACT_16BITS(message + 6);
                ND_PRINT((ndo, "seqno %u interval %s", seqno, format_interval(interval)));
            }
        }
            break;

        case MESSAGE_IHU: {
            unsigned short txcost, interval;
            if (!ndo->ndo_vflag)
                ND_PRINT((ndo, " ihu"));
            else {
                u_char address[16];
                int rc;
                ND_PRINT((ndo, "\n\tIHU "));
                if(len < 6) goto corrupt;
                txcost = EXTRACT_16BITS(message + 4);
                interval = EXTRACT_16BITS(message + 6);
                rc = network_address(message[2], message + 8, len - 6, address);
                if(rc < 0) { ND_PRINT((ndo, "%s", tstr)); break; }
//.........这里部分代码省略.........

void
tcp_print(register const u_char *bp, register u_int length,
	  register const u_char *bp2, int fragmented)
{
        register const struct tcphdr *tp;
        register const struct ip *ip;
        register u_char flags;
        register u_int hlen;
        register char ch;
        u_int16_t sport, dport, win, urp;
        u_int32_t seq, ack, thseq, thack;
        u_int utoval;
        u_int16_t magic;
        register int rev;
#ifdef INET6
        register const struct ip6_hdr *ip6;
#endif

        tp = (struct tcphdr *)bp;
        ip = (struct ip *)bp2;
#ifdef INET6
        if (IP_V(ip) == 6)
                ip6 = (struct ip6_hdr *)bp2;
        else
                ip6 = NULL;
#endif /*INET6*/
        ch = '\0';
        if (!TTEST(tp->th_dport)) {
                (void)printf("%s > %s: [|tcp]",
                             ipaddr_string(&ip->ip_src),
                             ipaddr_string(&ip->ip_dst));
                return;
        }

        sport = EXTRACT_16BITS(&tp->th_sport);
        dport = EXTRACT_16BITS(&tp->th_dport);

        hlen = TH_OFF(tp) * 4;

#ifdef INET6
        if (ip6) {
                if (ip6->ip6_nxt == IPPROTO_TCP) {
                        (void)printf("%s.%s > %s.%s: ",
                                     ip6addr_string(&ip6->ip6_src),
                                     tcpport_string(sport),
                                     ip6addr_string(&ip6->ip6_dst),
                                     tcpport_string(dport));
                } else {
                        (void)printf("%s > %s: ",
                                     tcpport_string(sport), tcpport_string(dport));
                }
        } else
#endif /*INET6*/
        {
                if (ip->ip_p == IPPROTO_TCP) {
                        (void)printf("%s.%s > %s.%s: ",
                                     ipaddr_string(&ip->ip_src),
                                     tcpport_string(sport),
                                     ipaddr_string(&ip->ip_dst),
                                     tcpport_string(dport));
                } else {
                        (void)printf("%s > %s: ",
                                     tcpport_string(sport), tcpport_string(dport));
                }
        }

        if (hlen < sizeof(*tp)) {
                (void)printf(" tcp %d [bad hdr length %u - too short, < %lu]",
                             length - hlen, hlen, (unsigned long)sizeof(*tp));
                return;
        }

        TCHECK(*tp);

        seq = EXTRACT_32BITS(&tp->th_seq);
        ack = EXTRACT_32BITS(&tp->th_ack);
        win = EXTRACT_16BITS(&tp->th_win);
        urp = EXTRACT_16BITS(&tp->th_urp);

        if (qflag) {
                (void)printf("tcp %d", length - hlen);
                if (hlen > length) {
                        (void)printf(" [bad hdr length %u - too long, > %u]",
                                     hlen, length);
                }
                return;
        }

        flags = tp->th_flags;
        printf("Flags [%s]", bittok2str_nosep(tcp_flag_values, "none", flags));

        if (!Sflag && (flags & TH_ACK)) {
                /*
                 * Find (or record) the initial sequence numbers for
                 * this conversation.  (we pick an arbitrary
                 * collating order so there's only one entry for
                 * both directions).
                 */
                rev = 0;
#ifdef INET6
//.........这里部分代码省略.........

/*
 * Print trivial file transfer program requests
 */
void
tftp_print(register const u_char *bp, u_int length)
{
	register const struct tftphdr *tp;
	register const char *cp;
	register const u_char *p;
	register int opcode, i;
	static char tstr[] = " [|tftp]";

	tp = (const struct tftphdr *)bp;

	/* Print length */
	printf(" %d", length);

	/* Print tftp request type */
	TCHECK(tp->th_opcode);
	opcode = EXTRACT_16BITS(&tp->th_opcode);
	cp = tok2str(op2str, "tftp-#%d", opcode);
	printf(" %s", cp);
	/* Bail if bogus opcode */
	if (*cp == 't')
		return;

	switch (opcode) {

	case RRQ:
	case WRQ:
	case OACK:
		/*
		 * XXX Not all arpa/tftp.h's specify th_stuff as any
		 * array; use address of th_block instead
		 */
#ifdef notdef
		p = (u_char *)tp->th_stuff;
#else
		p = (u_char *)&tp->th_block;
#endif
		putchar(' ');
		/* Print filename or first option */
		if (opcode != OACK)
			putchar('"');
		i = fn_print(p, snapend);
		if (opcode != OACK)
			putchar('"');

		/* Print the mode (RRQ and WRQ only) and any options */
		while ((p = (const u_char *)strchr((const char *)p, '\0')) != NULL) {
			if (length <= (u_int)(p - (const u_char *)&tp->th_block))
				break;
			p++;
			if (*p != '\0') {
				putchar(' ');
				fn_print(p, snapend);
			}
		}
		
		if (i)
			goto trunc;
		break;

	case ACK:
	case DATA:
		TCHECK(tp->th_block);
		printf(" block %d", EXTRACT_16BITS(&tp->th_block));
		break;

	case TFTP_ERROR:
		/* Print error code string */
		TCHECK(tp->th_code);
		printf(" %s \"", tok2str(err2str, "tftp-err-#%d \"",
				       EXTRACT_16BITS(&tp->th_code)));
		/* Print error message string */
		i = fn_print((const u_char *)tp->th_data, snapend);
		putchar('"');
		if (i)
			goto trunc;
		break;

	default:
		/* We shouldn't get here */
		printf("(unknown #%d)", opcode);
		break;
	}
	return;
trunc:
	fputs(tstr, stdout);
	return;
}

/****************************************************************************
 *
 * Function: TCPOptionValue(Options *o)
 *
 * Purpose: To return a string representing the value of an TCP option
 *
 * Arguments: An Options struct.
 *
 * Returns: char * -- You must free this char * when you are done with it.
 *
 ***************************************************************************/
char *TCPOptionValue(Options *o)
{
    char * rval;
    char * rvalptr;
    u_char tmp[5];
    int x;

    rval = (char *)malloc(SMALLBUFFER);
    rvalptr = rval;

    switch(o->code)
    {
        case TCPOPT_MAXSEG:
            bzero((char *)tmp, 5);
            strncpy(tmp, o->data, 2); 
            snprintf(rval, SMALLBUFFER, "%u", EXTRACT_16BITS(tmp));
            break;

        case TCPOPT_EOL:
            rval[0] = '\0';
            break;

        case TCPOPT_NOP:
            rval[0] = '\0';
            break;

        case TCPOPT_WSCALE:
            snprintf(rval, SMALLBUFFER, "%u", o->data[0]);
            break;

        case TCPOPT_SACK:
            bzero((char *)tmp, 5);
            memcpy(tmp, o->data, 2);
            snprintf(rval, SMALLBUFFER, "%[email protected]", EXTRACT_16BITS(tmp));
            x = strlen(rval);
            rvalptr += x;
            bzero((char *)tmp, 5);
            memcpy(tmp, (o->data)+2, 2);
            snprintf(rvalptr, SMALLBUFFER - x, "%u", EXTRACT_16BITS(tmp));
            break;

        case TCPOPT_SACKOK:
            rval[0] = '\0';
            break;

        case TCPOPT_ECHO:
            bzero((char *)tmp, 5);
            memcpy(tmp, o->data, 4);
            snprintf(rval, SMALLBUFFER, "%u", EXTRACT_32BITS(tmp));
            break;

        case TCPOPT_ECHOREPLY:
            bzero((char *)tmp, 5);
            memcpy(tmp, o->data, 4);
            snprintf(rval, SMALLBUFFER, "%u", EXTRACT_32BITS(tmp));
            break;

        case TCPOPT_TIMESTAMP:
            bzero((char *)tmp, 5);
            memcpy(tmp, o->data, 4);
            snprintf(rval, SMALLBUFFER, "%u ", EXTRACT_32BITS(tmp));
            rvalptr += strlen(rval);
            bzero((char *)tmp, 5);
            memcpy(tmp, (o->data)+4, 4);
            snprintf(rvalptr, SMALLBUFFER, "%u", EXTRACT_32BITS(tmp));
            break;

        case TCPOPT_CC:
            bzero((char *)tmp, 5);
            memcpy(tmp, o->data, 4);
            snprintf(rval, SMALLBUFFER, "%u", EXTRACT_32BITS(tmp));
            break;

        case TCPOPT_CCNEW:
            bzero((char *)tmp, 5);
            memcpy(tmp, o->data, 4);
            snprintf(rval, SMALLBUFFER, "%u", EXTRACT_32BITS(tmp));
            break;

        case TCPOPT_CCECHO:
            bzero((char *)tmp, 5);
            memcpy(tmp, o->data, 4);
            snprintf(rval, SMALLBUFFER, "%u", EXTRACT_32BITS(tmp));
            break;

        default:
            rval[0] = '\0';
            if(o->len > 2)
            {
//.........这里部分代码省略.........

/**
 * dccp_print - show dccp packet
 * @bp - beginning of dccp packet
 * @data2 - beginning of enclosing
 * @len - lenght of ip packet
 */
void dccp_print(const u_char *bp, const u_char *data2, u_int len)
{
	const struct dccp_hdr *dh;
	const struct ip *ip;
#ifdef INET6
	const struct ip6_hdr *ip6;
#endif
	const u_char *cp;
	u_short sport, dport;
	u_int hlen;
	u_int fixed_hdrlen;

	dh = (const struct dccp_hdr *)bp;

	ip = (struct ip *)data2;
#ifdef INET6
	if (IP_V(ip) == 6)
		ip6 = (const struct ip6_hdr *)data2;
	else
		ip6 = NULL;
#endif /*INET6*/

	/* make sure we have enough data to look at the X bit */
	cp = (const u_char *)(dh + 1);
	if (cp > snapend) {
		printf("[Invalid packet|dccp]");
		return;
	}
	if (len < sizeof(struct dccp_hdr)) {
		printf("truncated-dccp - %u bytes missing!",
			     len - (u_int)sizeof(struct dccp_hdr));
		return;
	}

	/* get the length of the generic header */
	fixed_hdrlen = dccp_basic_hdr_len(dh);
	if (len < fixed_hdrlen) {
		printf("truncated-dccp - %u bytes missing!",
			     len - fixed_hdrlen);
		return;
	}
	TCHECK2(*dh, fixed_hdrlen);

	sport = EXTRACT_16BITS(&dh->dccph_sport);
	dport = EXTRACT_16BITS(&dh->dccph_dport);
	hlen = dh->dccph_doff * 4;

#ifdef INET6
	if (ip6) {
		(void)printf("%s.%d > %s.%d: ",
			     ip6addr_string(&ip6->ip6_src), sport,
			     ip6addr_string(&ip6->ip6_dst), dport);
	} else
#endif /*INET6*/
	{
		(void)printf("%s.%d > %s.%d: ",
			     ipaddr_string(&ip->ip_src), sport,
			     ipaddr_string(&ip->ip_dst), dport);
	}
	fflush(stdout);

	if (qflag) {
		(void)printf(" %d", len - hlen);
		if (hlen > len) {
			(void)printf("dccp [bad hdr length %u - too long, > %u]",
			    hlen, len);
		}
		return;
	}

	/* other variables in generic header */
	if (vflag) {
		(void)printf("CCVal %d, CsCov %d, ", DCCPH_CCVAL(dh), DCCPH_CSCOV(dh));
	}

	/* checksum calculation */
	if (vflag && TTEST2(bp[0], len)) {
		u_int16_t sum = 0, dccp_sum;

		dccp_sum = EXTRACT_16BITS(&dh->dccph_checksum);
		(void)printf("cksum 0x%04x ", dccp_sum);
		if (IP_V(ip) == 4)
			sum = dccp_cksum(ip, dh, len);
#ifdef INET6
		else if (IP_V(ip) == 6)
			sum = dccp6_cksum(ip6, dh, len);
#endif
		if (sum != 0)
			(void)printf("(incorrect -> 0x%04x), ",in_cksum_shouldbe(dccp_sum, sum));
		else
			(void)printf("(correct), ");
	}

	switch (DCCPH_TYPE(dh)) {
//.........这里部分代码省略.........

void
icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *bp2,
           int fragmented)
{
	char *cp;
	const struct icmp *dp;
        const struct icmp_ext_t *ext_dp;
	const struct ip *ip;
	const char *str, *fmt;
	const struct ip *oip;
	const struct udphdr *ouh;
        const uint8_t *obj_tptr;
        uint32_t raw_label;
        const u_char *snapend_save;
	const struct icmp_mpls_ext_object_header_t *icmp_mpls_ext_object_header;
	u_int hlen, dport, mtu, obj_tlen, obj_class_num, obj_ctype;
	char buf[MAXHOSTNAMELEN + 100];
	struct cksum_vec vec[1];

	dp = (const struct icmp *)bp;
        ext_dp = (const struct icmp_ext_t *)bp;
	ip = (const struct ip *)bp2;
	str = buf;

	ND_TCHECK(dp->icmp_code);
	switch (dp->icmp_type) {

	case ICMP_ECHO:
	case ICMP_ECHOREPLY:
		ND_TCHECK(dp->icmp_seq);
		(void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u",
                               dp->icmp_type == ICMP_ECHO ?
                               "request" : "reply",
                               EXTRACT_16BITS(&dp->icmp_id),
                               EXTRACT_16BITS(&dp->icmp_seq));
		break;

	case ICMP_UNREACH:
		ND_TCHECK(dp->icmp_ip.ip_dst);
		switch (dp->icmp_code) {

		case ICMP_UNREACH_PROTOCOL:
			ND_TCHECK(dp->icmp_ip.ip_p);
			(void)snprintf(buf, sizeof(buf),
			    "%s protocol %d unreachable",
			    ipaddr_string(ndo, &dp->icmp_ip.ip_dst),
			    dp->icmp_ip.ip_p);
			break;

		case ICMP_UNREACH_PORT:
			ND_TCHECK(dp->icmp_ip.ip_p);
			oip = &dp->icmp_ip;
			hlen = IP_HL(oip) * 4;
			ouh = (const struct udphdr *)(((const u_char *)oip) + hlen);
			ND_TCHECK(ouh->uh_dport);
			dport = EXTRACT_16BITS(&ouh->uh_dport);
			switch (oip->ip_p) {

			case IPPROTO_TCP:
				(void)snprintf(buf, sizeof(buf),
					"%s tcp port %s unreachable",
					ipaddr_string(ndo, &oip->ip_dst),
					tcpport_string(ndo, dport));
				break;

			case IPPROTO_UDP:
				(void)snprintf(buf, sizeof(buf),
					"%s udp port %s unreachable",
					ipaddr_string(ndo, &oip->ip_dst),
					udpport_string(ndo, dport));
				break;

			default:
				(void)snprintf(buf, sizeof(buf),
					"%s protocol %d port %d unreachable",
					ipaddr_string(ndo, &oip->ip_dst),
					oip->ip_p, dport);
				break;
			}
			break;

		case ICMP_UNREACH_NEEDFRAG:
		    {
			register const struct mtu_discovery *mp;
			mp = (const struct mtu_discovery *)(const u_char *)&dp->icmp_void;
			mtu = EXTRACT_16BITS(&mp->nexthopmtu);
			if (mtu) {
				(void)snprintf(buf, sizeof(buf),
				    "%s unreachable - need to frag (mtu %d)",
				    ipaddr_string(ndo, &dp->icmp_ip.ip_dst), mtu);
			} else {
				(void)snprintf(buf, sizeof(buf),
				    "%s unreachable - need to frag",
				    ipaddr_string(ndo, &dp->icmp_ip.ip_dst));
			}
		    }
			break;

		default:
			fmt = tok2str(unreach2str, "#%d %%s unreachable",
//.........这里部分代码省略.........

static void
slow_marker_lacp_print(netdissect_options *ndo,
                       register const u_char *tptr, register u_int tlen) {

    const struct tlv_header_t *tlv_header;
    const u_char *tlv_tptr;
    u_int tlv_len, tlv_tlen;

    union {
        const struct lacp_marker_tlv_terminator_t *lacp_marker_tlv_terminator;
        const struct lacp_tlv_actor_partner_info_t *lacp_tlv_actor_partner_info;
        const struct lacp_tlv_collector_info_t *lacp_tlv_collector_info;
        const struct marker_tlv_marker_info_t *marker_tlv_marker_info;
    } tlv_ptr;

    while(tlen>0) {
        /* did we capture enough for fully decoding the tlv header ? */
        ND_TCHECK2(*tptr, sizeof(struct tlv_header_t));
        tlv_header = (const struct tlv_header_t *)tptr;
        tlv_len = tlv_header->length;

        ND_PRINT((ndo, "\n\t%s TLV (0x%02x), length %u",
               tok2str(slow_tlv_values,
                       "Unknown",
                       (slow_com_header->proto_subtype << 8) + tlv_header->type),
               tlv_header->type,
               tlv_len));

        if ((tlv_len < sizeof(struct tlv_header_t) ||
            tlv_len > tlen) &&
            tlv_header->type != LACP_TLV_TERMINATOR &&
            tlv_header->type != MARKER_TLV_TERMINATOR) {
            ND_PRINT((ndo, "\n\t-----trailing data-----"));
            print_unknown_data(ndo, tptr+sizeof(struct tlv_header_t), "\n\t  ", tlen);
            return;
        }

        tlv_tptr=tptr+sizeof(struct tlv_header_t);
        tlv_tlen=tlv_len-sizeof(struct tlv_header_t);

        /* did we capture enough for fully decoding the tlv ? */
        ND_TCHECK2(*tptr, tlv_len);

        switch((slow_com_header->proto_subtype << 8) + tlv_header->type) {

            /* those two TLVs have the same structure -> fall through */
        case ((SLOW_PROTO_LACP << 8) + LACP_TLV_ACTOR_INFO):
        case ((SLOW_PROTO_LACP << 8) + LACP_TLV_PARTNER_INFO):
            tlv_ptr.lacp_tlv_actor_partner_info = (const struct lacp_tlv_actor_partner_info_t *)tlv_tptr;

            ND_PRINT((ndo, "\n\t  System %s, System Priority %u, Key %u" \
                   ", Port %u, Port Priority %u\n\t  State Flags [%s]",
                   etheraddr_string(ndo, tlv_ptr.lacp_tlv_actor_partner_info->sys),
                   EXTRACT_16BITS(tlv_ptr.lacp_tlv_actor_partner_info->sys_pri),
                   EXTRACT_16BITS(tlv_ptr.lacp_tlv_actor_partner_info->key),
                   EXTRACT_16BITS(tlv_ptr.lacp_tlv_actor_partner_info->port),
                   EXTRACT_16BITS(tlv_ptr.lacp_tlv_actor_partner_info->port_pri),
                   bittok2str(lacp_tlv_actor_partner_info_state_values,
                              "none",
                              tlv_ptr.lacp_tlv_actor_partner_info->state)));

            break;

        case ((SLOW_PROTO_LACP << 8) + LACP_TLV_COLLECTOR_INFO):
            tlv_ptr.lacp_tlv_collector_info = (const struct lacp_tlv_collector_info_t *)tlv_tptr;

            ND_PRINT((ndo, "\n\t  Max Delay %u",
                   EXTRACT_16BITS(tlv_ptr.lacp_tlv_collector_info->max_delay)));

            break;

        case ((SLOW_PROTO_MARKER << 8) + MARKER_TLV_MARKER_INFO):
            tlv_ptr.marker_tlv_marker_info = (const struct marker_tlv_marker_info_t *)tlv_tptr;

            ND_PRINT((ndo, "\n\t  Request System %s, Request Port %u, Request Transaction ID 0x%08x",
                   etheraddr_string(ndo, tlv_ptr.marker_tlv_marker_info->req_sys),
                   EXTRACT_16BITS(tlv_ptr.marker_tlv_marker_info->req_port),
                   EXTRACT_32BITS(tlv_ptr.marker_tlv_marker_info->req_trans_id)));

            break;

            /* those two TLVs have the same structure -> fall through */
        case ((SLOW_PROTO_LACP << 8) + LACP_TLV_TERMINATOR):
        case ((SLOW_PROTO_MARKER << 8) + LACP_TLV_TERMINATOR):
            tlv_ptr.lacp_marker_tlv_terminator = (const struct lacp_marker_tlv_terminator_t *)tlv_tptr;
            if (tlv_len == 0) {
                tlv_len = sizeof(tlv_ptr.lacp_marker_tlv_terminator->pad) +
                    sizeof(struct tlv_header_t);
                /* tell the user that we modified the length field  */
                if (ndo->ndo_vflag>1)
                    ND_PRINT((ndo, " (=%u)", tlv_len));
                /* we have messed around with the length field - now we need to check
                 * again if there are enough bytes on the wire for the hexdump */
                ND_TCHECK2(tlv_ptr.lacp_marker_tlv_terminator->pad[0],
                        sizeof(tlv_ptr.lacp_marker_tlv_terminator->pad));
            }

            break;

        default:
//.........这里部分代码省略.........

void
udld_print (const u_char *pptr, u_int length)
{
    int code, type, len;
    const u_char *tptr;

    if (length < UDLD_HEADER_LEN)
        goto trunc;

    tptr = pptr; 

    if (!TTEST2(*tptr, UDLD_HEADER_LEN))	
	goto trunc;

    code = UDLD_EXTRACT_OPCODE(*tptr);

    printf("UDLDv%u, Code %s (%x), Flags [%s] (0x%02x), length %u", 
           UDLD_EXTRACT_VERSION(*tptr),
           tok2str(udld_code_values, "Reserved", code),
           code,
           bittok2str(udld_flags_values, "none", *(tptr+1)),
           *(tptr+1),
           length);

    /*
     * In non-verbose mode, just print version and opcode type
     */
    if (vflag < 1) {
	return;
    }

    printf("\n\tChecksum 0x%04x (unverified)", EXTRACT_16BITS(tptr+2));

    tptr += UDLD_HEADER_LEN;

    while (tptr < (pptr+length)) {

        if (!TTEST2(*tptr, 4)) 
            goto trunc;

	type = EXTRACT_16BITS(tptr);
        len  = EXTRACT_16BITS(tptr+2); 
        len -= 4;
        tptr += 4;

        /* infinite loop check */
        if (type == 0 || len == 0) {
            return;
        }

        printf("\n\t%s (0x%04x) TLV, length %u",
               tok2str(udld_tlv_values, "Unknown", type),
               type, len);

        switch (type) {
        case UDLD_DEVICE_ID_TLV:
        case UDLD_PORT_ID_TLV:
        case UDLD_ECHO_TLV:
        case UDLD_DEVICE_NAME_TLV: 
            printf(", %s", tptr);
            break;

        case UDLD_MESSAGE_INTERVAL_TLV: 
        case UDLD_TIMEOUT_INTERVAL_TLV:
            printf(", %us", (*tptr));
            break;

        case UDLD_SEQ_NUMBER_TLV:
            printf(", %u", EXTRACT_32BITS(tptr));
            break;

        default:
            break;
        }	
        tptr += len;
    }

    return;

 trunc:
    printf("[|udld]");
}

void
icmp_print(const u_char *bp, u_int length, const u_char *bp2)
{
	const struct icmp *dp;
	const struct ip *ip;
	const char *str, *fmt;
	const struct ip *oip;
	const struct udphdr *ouh;
	u_int hlen, dport, mtu;
	char buf[MAXHOSTNAMELEN+256];
	char buf2[MAXHOSTNAMELEN+256];

	dp = (struct icmp *)bp;
	ip = (struct ip *)bp2;
	str = buf;

        (void)printf("%s > %s: ",
		ipaddr_string(&ip->ip_src),
		ipaddr_string(&ip->ip_dst));

	TCHECK(dp->icmp_code);
	if (qflag) 
		(void) snprintf(buf, sizeof buf, "%u %u", dp->icmp_type,
		    dp->icmp_code);
	else switch (dp->icmp_type) {

	case ICMP_ECHOREPLY:
	case ICMP_ECHO:
		if (vflag) {
			TCHECK(dp->icmp_seq);
			(void)snprintf(buf, sizeof buf,
				       "echo %s (id:%04x seq:%u)",
				       (dp->icmp_type == ICMP_ECHO)?
				       "request": "reply",
				       ntohs(dp->icmp_id),
				       ntohs(dp->icmp_seq));
		} else
			str = tok2str(icmp2str, "type-#%u", dp->icmp_type);
		break;

	case ICMP_UNREACH:
		TCHECK(dp->icmp_ip.ip_dst);
		switch (dp->icmp_code) {

		case ICMP_UNREACH_PROTOCOL:
			TCHECK(dp->icmp_ip.ip_p);
			(void)snprintf(buf, sizeof buf,
				       "%s protocol %u unreachable",
				       ipaddr_string(&dp->icmp_ip.ip_dst),
				       dp->icmp_ip.ip_p);
			break;

		case ICMP_UNREACH_PORT:
			TCHECK(dp->icmp_ip.ip_p);
			oip = &dp->icmp_ip;
			hlen = oip->ip_hl * 4;
			ouh = (struct udphdr *)(((u_char *)oip) + hlen);
			TCHECK(ouh->uh_dport);
			dport = ntohs(ouh->uh_dport);
			switch (oip->ip_p) {

			case IPPROTO_TCP:
				(void)snprintf(buf, sizeof buf,
					"%s tcp port %s unreachable",
					ipaddr_string(&oip->ip_dst),
					tcpport_string(dport));
				break;

			case IPPROTO_UDP:
				(void)snprintf(buf, sizeof buf,
					"%s udp port %s unreachable",
					ipaddr_string(&oip->ip_dst),
					udpport_string(dport));
				break;

			default:
				(void)snprintf(buf, sizeof buf,
					"%s protocol %u port %u unreachable",
					ipaddr_string(&oip->ip_dst),
					oip->ip_p, dport);
				break;
			}
			break;

		case ICMP_UNREACH_NEEDFRAG:
			{
			const struct mtu_discovery *mp;

			mp = (struct mtu_discovery *)&dp->icmp_void;
                        mtu = EXTRACT_16BITS(&mp->nexthopmtu);
                        if (mtu)
			    (void)snprintf(buf, sizeof buf,
				"%s unreachable - need to frag (mtu %u)",
				ipaddr_string(&dp->icmp_ip.ip_dst), mtu);
                        else
			    (void)snprintf(buf, sizeof buf,
				"%s unreachable - need to frag",
				ipaddr_string(&dp->icmp_ip.ip_dst));
			}
			break;
//.........这里部分代码省略.........

void
msdp_print(netdissect_options *ndo, const u_char *sp, u_int length)
{
	unsigned int type, len;

	ND_TCHECK2(*sp, 3);
	/* See if we think we're at the beginning of a compound packet */
	type = *sp;
	len = EXTRACT_16BITS(sp + 1);
	if (len > 1500 || len < 3 || type == 0 || type > MSDP_TYPE_MAX)
		goto trunc;	/* not really truncated, but still not decodable */
	ND_PRINT((ndo, " msdp:"));
	while (length > 0) {
		ND_TCHECK2(*sp, 3);
		type = *sp;
		len = EXTRACT_16BITS(sp + 1);
		if (len > 1400 || ndo->ndo_vflag)
			ND_PRINT((ndo, " [len %u]", len));
		if (len < 3)
			goto trunc;
		sp += 3;
		length -= 3;
		switch (type) {
		case 1:	/* IPv4 Source-Active */
		case 3: /* IPv4 Source-Active Response */
			if (type == 1)
				ND_PRINT((ndo, " SA"));
			else
				ND_PRINT((ndo, " SA-Response"));
			ND_TCHECK(*sp);
			ND_PRINT((ndo, " %u entries", *sp));
			if ((u_int)((*sp * 12) + 8) < len) {
				ND_PRINT((ndo, " [w/data]"));
				if (ndo->ndo_vflag > 1) {
					ND_PRINT((ndo, " "));
					ip_print(ndo, sp + *sp * 12 + 8 - 3,
					         len - (*sp * 12 + 8));
				}
			}
			break;
		case 2:
			ND_PRINT((ndo, " SA-Request"));
			ND_TCHECK2(*sp, 5);
			ND_PRINT((ndo, " for %s", ipaddr_string(sp + 1)));
			break;
		case 4:
			ND_PRINT((ndo, " Keepalive"));
			if (len != 3)
				ND_PRINT((ndo, "[len=%d] ", len));
			break;
		case 5:
			ND_PRINT((ndo, " Notification"));
			break;
		default:
			ND_PRINT((ndo, " [type=%d len=%d]", type, len));
			break;
		}
		sp += (len - 3);
		length -= (len - 3);
	}
	return;
trunc:
	ND_PRINT((ndo, " [|msdp]"));
}

/**
 * dccp_print - show dccp packet
 * @bp - beginning of dccp packet
 * @data2 - beginning of enclosing
 * @len - lenght of ip packet
 */
void dccp_print(netdissect_options *ndo, const u_char *bp, const u_char *data2,
		u_int len)
{
	const struct dccp_hdr *dh;
	const struct ip *ip;
#ifdef INET6
	const struct ip6_hdr *ip6;
#endif
	const u_char *cp;
	u_short sport, dport;
	u_int hlen;
	u_int fixed_hdrlen;
	uint8_t	dccph_type;

	dh = (const struct dccp_hdr *)bp;

	ip = (const struct ip *)data2;
#ifdef INET6
	if (IP_V(ip) == 6)
		ip6 = (const struct ip6_hdr *)data2;
	else
		ip6 = NULL;
#endif /*INET6*/

	/* make sure we have enough data to look at the X bit */
	cp = (const u_char *)(dh + 1);
	if (cp > ndo->ndo_snapend) {
		ND_PRINT((ndo, "[Invalid packet|dccp]"));
		return;
	}
	if (len < sizeof(struct dccp_hdr)) {
		ND_PRINT((ndo, "truncated-dccp - %u bytes missing!",
			  len - (u_int)sizeof(struct dccp_hdr)));
		return;
	}

	/* get the length of the generic header */
	fixed_hdrlen = dccp_basic_hdr_len(dh);
	if (len < fixed_hdrlen) {
		ND_PRINT((ndo, "truncated-dccp - %u bytes missing!",
			  len - fixed_hdrlen));
		return;
	}
	ND_TCHECK2(*dh, fixed_hdrlen);

	sport = EXTRACT_16BITS(&dh->dccph_sport);
	dport = EXTRACT_16BITS(&dh->dccph_dport);
	hlen = dh->dccph_doff * 4;

#ifdef INET6
	if (ip6) {
		ND_PRINT((ndo, "%s.%d > %s.%d: ",
			  ip6addr_string(ndo, &ip6->ip6_src), sport,
			  ip6addr_string(ndo, &ip6->ip6_dst), dport));
	} else
#endif /*INET6*/
	{
		ND_PRINT((ndo, "%s.%d > %s.%d: ",
			  ipaddr_string(ndo, &ip->ip_src), sport,
			  ipaddr_string(ndo, &ip->ip_dst), dport));
	}

	ND_PRINT((ndo, "DCCP"));

	if (ndo->ndo_qflag) {
		ND_PRINT((ndo, " %d", len - hlen));
		if (hlen > len) {
			ND_PRINT((ndo, " [bad hdr length %u - too long, > %u]",
				  hlen, len));
		}
		return;
	}

	/* other variables in generic header */
	if (ndo->ndo_vflag) {
		ND_PRINT((ndo, " (CCVal %d, CsCov %d, ", DCCPH_CCVAL(dh), DCCPH_CSCOV(dh)));
	}

	/* checksum calculation */
	if (ndo->ndo_vflag && ND_TTEST2(bp[0], len)) {
		uint16_t sum = 0, dccp_sum;

		dccp_sum = EXTRACT_16BITS(&dh->dccph_checksum);
		ND_PRINT((ndo, "cksum 0x%04x ", dccp_sum));
		if (IP_V(ip) == 4)
			sum = dccp_cksum(ndo, ip, dh, len);
#ifdef INET6
		else if (IP_V(ip) == 6)
			sum = dccp6_cksum(ip6, dh, len);
#endif
		if (sum != 0)
			ND_PRINT((ndo, "(incorrect -> 0x%04x)",in_cksum_shouldbe(dccp_sum, sum)));
		else
			ND_PRINT((ndo, "(correct)"));
//.........这里部分代码省略.........