Example #1
0
void
carp_print(packetbody_t bp, register u_int len, int ttl)
{
	int version, type;
	const char *type_s;

	PACKET_HAS_ONE_OR_TRUNC(bp);
	version = (bp[0] & 0xf0) >> 4;
	type = bp[0] & 0x0f;
	if (type == 1)
		type_s = "advertise";
	else
		type_s = "unknown";
	printf("CARPv%d-%s %d: ", version, type_s, len);
	if (ttl != 255)
		printf("[ttl=%d!] ", ttl);
	if (version != 2 || type != 1)
		return;
	PACKET_HAS_SPACE_OR_TRUNC(bp, 6);
	printf("vhid=%d advbase=%d advskew=%d authlen=%d ",
	    bp[1], bp[5], bp[2], bp[3]);
	if (vflag) {
		struct cksum_vec vec[1];
		vec[0].ptr = (packetbody_t)bp;
		vec[0].len = len;
		if (PACKET_HAS_SPACE(bp, len) && in_cksum(vec, 1))
			printf(" (bad carp cksum %x!)",
				EXTRACT_16BITS(&bp[6]));
	}
	printf("counter=%" PRIu64, EXTRACT_64BITS(&bp[8]));

	return;
trunc:
	printf("[|carp]");
}
Example #2
0
int
ah_print(packetbody_t bp)
{
    __capability const struct ah *ah;
    int sumlen;
    u_int32_t spi;

    ah = (__capability const struct ah *)bp;

    PACKET_HAS_ONE_OR_TRUNC(ah);

    sumlen = ah->ah_len << 2;
    spi = EXTRACT_32BITS(&ah->ah_spi);

    printf("AH(spi=0x%08x", spi);
    if (vflag)
        printf(",sumlen=%d", sumlen);
    printf(",seq=0x%x", EXTRACT_32BITS(ah + 1));
    /* XXX-BD: previous code allowed 1-byte short packets */
    if (!PACKET_HAS_SPACE(bp, sizeof(struct ah) + sumlen))
        fputs("[truncated]", stdout);
    fputs("): ", stdout);

    return sizeof(struct ah) + sumlen;
trunc:
    fputs("[|AH]", stdout);
    return -1;
}
Example #3
0
void
olsr_print (packetbody_t pptr, u_int length, int is_ipv6)
{
    union {
        __capability const struct olsr_common *common;
        __capability const struct olsr_msg4 *msg4;
        __capability const struct olsr_msg6 *msg6;
        __capability const struct olsr_hello *hello;
        __capability const struct olsr_hello_link *hello_link;
        __capability const struct olsr_tc *tc;
        __capability const struct olsr_hna4 *hna;
    } ptr;

    u_int msg_type, msg_len, msg_tlen, hello_len;
    u_int16_t name_entry_type, name_entry_len;
    u_int name_entry_padding;
    u_int8_t link_type, neighbor_type;
    packetbody_t tptr, msg_data;

    tptr = pptr;

    if (length < sizeof(struct olsr_common)) {
        goto trunc;
    }

    if (!PACKET_HAS_SPACE(tptr, sizeof(struct olsr_common))) {
        goto trunc;
    }

    ptr.common = (__capability struct olsr_common *)tptr;
    length = MIN(length, EXTRACT_16BITS(ptr.common->packet_len));

    printf("OLSRv%i, seq 0x%04x, length %u",
            (is_ipv6 == 0) ? 4 : 6,
            EXTRACT_16BITS(ptr.common->packet_seq),
            length);

    tptr += sizeof(struct olsr_common);

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

    while (tptr < (pptr+length)) {
        union
        {
            __capability struct olsr_msg4 *v4;
            __capability struct olsr_msg6 *v6;
        } msgptr;
        int msg_len_valid = 0;

        if (!PACKET_HAS_SPACE(tptr, sizeof(struct olsr_msg4)))
            goto trunc;

#if INET6
        if (is_ipv6)
        {
            msgptr.v6 = (__capability struct olsr_msg6 *) tptr;
            msg_type = msgptr.v6->msg_type;
            msg_len = EXTRACT_16BITS(msgptr.v6->msg_len);
            if ((msg_len >= sizeof (struct olsr_msg6))
                    && (msg_len <= length))
                msg_len_valid = 1;

            /* infinite loop check */
            if (msg_type == 0 || msg_len == 0) {
                return;
            }

            printf("\n\t%s Message (%#04x), originator %s, ttl %u, hop %u"
                    "\n\t  vtime %.3lfs, msg-seq 0x%04x, length %u%s",
                    tok2str(olsr_msg_values, "Unknown", msg_type),
                    msg_type, ip6addr_string(msgptr.v6->originator),
                    msgptr.v6->ttl,
                    msgptr.v6->hopcount,
                    ME_TO_DOUBLE(msgptr.v6->vtime),
                    EXTRACT_16BITS(msgptr.v6->msg_seq),
                    msg_len, (msg_len_valid == 0) ? " (invalid)" : "");

            msg_tlen = msg_len - sizeof(struct olsr_msg6);
            msg_data = tptr + sizeof(struct olsr_msg6);
        }
        else /* (!is_ipv6) */
#endif /* INET6 */
        {
            msgptr.v4 = (__capability struct olsr_msg4 *) tptr;
            msg_type = msgptr.v4->msg_type;
            msg_len = EXTRACT_16BITS(msgptr.v4->msg_len);
            if ((msg_len >= sizeof (struct olsr_msg4))
                    && (msg_len <= length))
                msg_len_valid = 1;

            /* infinite loop check */
            if (msg_type == 0 || msg_len == 0) {
                return;
            }

            printf("\n\t%s Message (%#04x), originator %s, ttl %u, hop %u"
                    "\n\t  vtime %.3lfs, msg-seq 0x%04x, length %u%s",
                    tok2str(olsr_msg_values, "Unknown", msg_type),
                    msg_type, ipaddr_string(msgptr.v4->originator),
                    msgptr.v4->ttl,
                    msgptr.v4->hopcount,
                    ME_TO_DOUBLE(msgptr.v4->vtime),
                    EXTRACT_16BITS(msgptr.v4->msg_seq),
                    msg_len, (msg_len_valid == 0) ? " (invalid)" : "");

            msg_tlen = msg_len - sizeof(struct olsr_msg4);
            msg_data = tptr + sizeof(struct olsr_msg4);
        }

        switch (msg_type) {
        case OLSR_HELLO_MSG:
        case OLSR_HELLO_LQ_MSG:
            if (!PACKET_HAS_SPACE(msg_data, sizeof(struct olsr_hello)))
                goto trunc;

            ptr.hello = (__capability struct olsr_hello *)msg_data;
            printf("\n\t  hello-time %.3lfs, MPR willingness %u",
                   ME_TO_DOUBLE(ptr.hello->htime), ptr.hello->will);
            msg_data += sizeof(struct olsr_hello);
            msg_tlen -= sizeof(struct olsr_hello);

            while (msg_tlen >= sizeof(struct olsr_hello_link)) {
                int hello_len_valid = 0;

                /*
                 * link-type.
                 */
                if (!PACKET_HAS_SPACE(msg_data, sizeof(struct olsr_hello_link)))
                    goto trunc;

                ptr.hello_link = (__capability struct olsr_hello_link *)msg_data;

                hello_len = EXTRACT_16BITS(ptr.hello_link->len);
                link_type = OLSR_EXTRACT_LINK_TYPE(ptr.hello_link->link_code);
                neighbor_type = OLSR_EXTRACT_NEIGHBOR_TYPE(ptr.hello_link->link_code);

                if ((hello_len <= msg_tlen)
                        && (hello_len >= sizeof(struct olsr_hello_link)))
                    hello_len_valid = 1;

                printf("\n\t    link-type %s, neighbor-type %s, len %u%s",
                       tok2str(olsr_link_type_values, "Unknown", link_type),
                       tok2str(olsr_neighbor_type_values, "Unknown", neighbor_type),
                       hello_len,
                       (hello_len_valid == 0) ? " (invalid)" : "");

                if (hello_len_valid == 0)
                    break;

                msg_data += sizeof(struct olsr_hello_link);
                msg_tlen -= sizeof(struct olsr_hello_link);
                hello_len -= sizeof(struct olsr_hello_link);

                if (msg_type == OLSR_HELLO_MSG) {
                    olsr_print_neighbor(msg_data, hello_len);
                } else {
#if INET6
                    if (is_ipv6)
                        olsr_print_lq_neighbor6(msg_data, hello_len);
                    else
#endif
                        olsr_print_lq_neighbor4(msg_data, hello_len);
                }

                msg_data += hello_len;
                msg_tlen -= hello_len;
            }
            break;

        case OLSR_TC_MSG:
        case OLSR_TC_LQ_MSG:
            if (!PACKET_HAS_SPACE(msg_data, sizeof(struct olsr_tc)))
                goto trunc;

            ptr.tc = (__capability struct olsr_tc *)msg_data;
            printf("\n\t    advertised neighbor seq 0x%04x",
                   EXTRACT_16BITS(ptr.tc->ans_seq));
            msg_data += sizeof(struct olsr_tc);
            msg_tlen -= sizeof(struct olsr_tc);

            if (msg_type == OLSR_TC_MSG) {
                olsr_print_neighbor(msg_data, msg_tlen);
            } else {
#if INET6
                if (is_ipv6)
                    olsr_print_lq_neighbor6(msg_data, msg_tlen);
                else
#endif
                    olsr_print_lq_neighbor4(msg_data, msg_tlen);
            }
            break;

        case OLSR_MID_MSG:
        {
            size_t addr_size = sizeof(struct in_addr);

#if INET6
            if (is_ipv6)
                addr_size = sizeof(struct in6_addr);
#endif

            while (msg_tlen >= addr_size) {
                if (!PACKET_HAS_SPACE(msg_data, addr_size))
                    goto trunc;

                printf("\n\t  interface address %s",
#if INET6
                        is_ipv6 ? ip6addr_string(msg_data) :
#endif
                        ipaddr_string(msg_data));
                msg_data += addr_size;
                msg_tlen -= addr_size;
            }
            break;
        }

        case OLSR_HNA_MSG:
            printf("\n\t  Advertised networks (total %u)",
                    (unsigned int) (msg_tlen / sizeof(struct olsr_hna6)));
#if INET6
            if (is_ipv6)
            {
                int i = 0;
                while (msg_tlen >= sizeof(struct olsr_hna6)) {
                    __capability struct olsr_hna6 *hna6;

                    if (!PACKET_HAS_SPACE(msg_data, sizeof(struct olsr_hna6)))
                        goto trunc;

                    hna6 = (__capability struct olsr_hna6 *)msg_data;

                    printf("\n\t    #%i: %s/%u",
                            i, ip6addr_string(hna6->network),
                            mask62plen (hna6->mask));

                    msg_data += sizeof(struct olsr_hna6);
                    msg_tlen -= sizeof(struct olsr_hna6);
                }
            }
            else
#endif
            {
                int col = 0;
                while (msg_tlen >= sizeof(struct olsr_hna4)) {
                    if (!PACKET_HAS_SPACE(msg_data, sizeof(struct olsr_hna4)))
                        goto trunc;

                    ptr.hna = (__capability struct olsr_hna4 *)msg_data;

                    /* print 4 prefixes per line */
                    if (col == 0)
                        printf ("\n\t    ");
                    else
                        printf (", ");

                    printf("%s/%u",
                            ipaddr_string(ptr.hna->network),
                            mask2plen(EXTRACT_32BITS(ptr.hna->mask)));

                    msg_data += sizeof(struct olsr_hna4);
                    msg_tlen -= sizeof(struct olsr_hna4);

                    col = (col + 1) % 4;
                }
            }
            break;

        case OLSR_NAMESERVICE_MSG:
        {
            u_int name_entries = EXTRACT_16BITS(msg_data+2);
            u_int addr_size = 4;
            int name_entries_valid = 0;
            u_int i;

            if (is_ipv6)
                addr_size = 16;

            if ((name_entries > 0)
                    && ((name_entries * (4 + addr_size)) <= msg_tlen))
                name_entries_valid = 1;

            if (msg_tlen < 4)
                goto trunc;
            if (!PACKET_HAS_SPACE(msg_data, 4))
                goto trunc;

            printf("\n\t  Version %u, Entries %u%s",
                   EXTRACT_16BITS(msg_data),
                   name_entries, (name_entries_valid == 0) ? " (invalid)" : "");

            if (name_entries_valid == 0)
                break;

            msg_data += 4;
            msg_tlen -= 4;

            for (i = 0; i < name_entries; i++) {
                int name_entry_len_valid = 0;

                if (msg_tlen < 4)
                    break;
                if (!PACKET_HAS_SPACE(msg_data, 4))
                    goto trunc;

                name_entry_type = EXTRACT_16BITS(msg_data);
                name_entry_len = EXTRACT_16BITS(msg_data+2);

                msg_data += 4;
                msg_tlen -= 4;

                if ((name_entry_len > 0) && ((addr_size + name_entry_len) <= msg_tlen))
                    name_entry_len_valid = 1;

                printf("\n\t    #%u: type %#06x, length %u%s",
                        (unsigned int) i, name_entry_type,
                        name_entry_len, (name_entry_len_valid == 0) ? " (invalid)" : "");

                if (name_entry_len_valid == 0)
                    break;

                /* 32-bit alignment */
                name_entry_padding = 0;
                if (name_entry_len%4 != 0)
                    name_entry_padding = 4-(name_entry_len%4);

                if (msg_tlen < addr_size + name_entry_len + name_entry_padding)
                    goto trunc;

                if (!PACKET_HAS_SPACE(msg_data, addr_size + name_entry_len + name_entry_padding))
                    goto trunc;

#if INET6
                if (is_ipv6)
                    printf(", address %s, name \"",
                            ip6addr_string(msg_data));
                else
#endif
                    printf(", address %s, name \"",
                            ipaddr_string(msg_data));
                fn_printn(msg_data + addr_size, name_entry_len, NULL);
                printf("\"");

                msg_data += addr_size + name_entry_len + name_entry_padding;
                msg_tlen -= addr_size + name_entry_len + name_entry_padding;
            } /* for (i = 0; i < name_entries; i++) */
            break;
        } /* case OLSR_NAMESERVICE_MSG */

            /*
             * FIXME those are the defined messages that lack a decoder
             * you are welcome to contribute code ;-)
             */
        case OLSR_POWERINFO_MSG:
        default:
            print_unknown_data(msg_data, "\n\t    ", msg_tlen);
            break;
        } /* switch (msg_type) */
        tptr += msg_len;
    } /* while (tptr < (pptr+length)) */

    return;

 trunc:
    printf("[|olsr]");
}
Example #4
0
void
syslog_print(packetbody_t pptr, register u_int len)
{
    u_int16_t msg_off = 0;
    u_int16_t pri = 0;
    u_int16_t facility,severity;

    /* extract decimal figures that are
     * encapsulated within < > tags
     * based on this decimal figure extract the
     * severity and facility values
     */

    if (!PACKET_HAS_SPACE(pptr, 1))
        goto trunc;

    if (*(pptr+msg_off) == '<') {
        msg_off++;

        PACKET_HAS_SPACE_OR_TRUNC(pptr, msg_off + 1);

        while ( *(pptr+msg_off) >= '0' &&
                *(pptr+msg_off) <= '9' &&
                msg_off <= SYSLOG_MAX_DIGITS) {

            PACKET_HAS_SPACE_OR_TRUNC(pptr, msg_off + 1);

            pri = pri * 10 + (*(pptr+msg_off) - '0');
            msg_off++;

            PACKET_HAS_SPACE_OR_TRUNC(pptr, msg_off + 1);

        if (*(pptr+msg_off) == '>')
            msg_off++;
        }
    } else {
        printf("[|syslog]");
        return;
    }

    facility = (pri & SYSLOG_FACILITY_MASK) >> 3;
    severity = pri & SYSLOG_SEVERITY_MASK;

    
    if (vflag < 1 )
    {
        printf("SYSLOG %s.%s, length: %u",
               tok2str(syslog_facility_values, "unknown (%u)", facility),
               tok2str(syslog_severity_values, "unknown (%u)", severity),
               len);
        return;
    }
       
    printf("SYSLOG, length: %u\n\tFacility %s (%u), Severity %s (%u)\n\tMsg: ",
           len,
           tok2str(syslog_facility_values, "unknown (%u)", facility),
           facility,
           tok2str(syslog_severity_values, "unknown (%u)", severity),
           severity);

    /* print the syslog text in verbose mode */
    for (; msg_off < len; msg_off++) {
        PACKET_HAS_SPACE_OR_TRUNC(pptr, msg_off + 1);
        safeputchar(*(pptr+msg_off));        
    }

    if (vflag > 1) {
        if(!print_unknown_data(pptr,"\n\t",len))
            return;
    }
    
    return;

trunc:
        printf("[|syslog]");
}
Example #5
0
void
tcp_print(packetbody_t bp, register u_int length,
	  packetbody_t bp2, int fragmented)
{
        __capability const struct tcphdr *tp;
        __capability 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;
        int threv;
#ifdef INET6
        __capability const struct ip6_hdr *ip6;
#endif

        tp = (__capability const struct tcphdr *)bp;
        ip = (__capability const struct ip *)bp2;
#ifdef INET6
        if (IP_V(ip) == 6)
                ip6 = (__capability const struct ip6_hdr *)bp2;
        else
                ip6 = NULL;
#endif /*INET6*/
        ch = '\0';
        if (!PACKET_HAS_ELEMENT(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;

        /*
	 * If data present, header length valid, and NFS port used,
	 * assume NFS.
	 * Pass offset of data plus 4 bytes for RPC TCP msg length
	 * to NFS print routines.
	 */
	if (!qflag && hlen >= sizeof(*tp) && hlen <= length &&
	    (length - hlen) >= 4) {
		packetbody_t fraglenp;
		u_int32_t fraglen;
		__capability const struct sunrpc_msg *rp;
		enum sunrpc_msg_type direction;

		fraglenp = (packetbody_t)tp + hlen;
		if (PACKET_HAS_SPACE(fraglenp, 4)) {
			fraglen = EXTRACT_32BITS(fraglenp) & 0x7FFFFFFF;
			if (fraglen > (length - hlen) - 4)
				fraglen = (length - hlen) - 4;
			rp = (__capability const struct sunrpc_msg *)(fraglenp + 4);
			if (PACKET_HAS_ELEMENT(rp, rm_direction)) {
				direction = (enum sunrpc_msg_type)EXTRACT_32BITS(&rp->rm_direction);
				if (dport == NFS_PORT &&
				    direction == SUNRPC_CALL) {
					nfsreq_print((packetbody_t)rp, fraglen,
					    (packetbody_t)ip);
					return;
				}
				if (sport == NFS_PORT &&
				    direction == SUNRPC_REPLY) {
					nfsreply_print((packetbody_t)rp,
					    fraglen, (packetbody_t)ip);
					return;
				}
			}
                }
        }
#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;
        }

        PACKET_HAS_ONE_OR_TRUNC(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)) {
                struct tcp_seq_hash *th;
                packetbody_t src, dst;
                register int rev;
                struct tha tha;
                /*
                 * 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).
                 */
#ifdef INET6
                rev = 0;
                if (ip6) {
                        src = (packetbody_t)&ip6->ip6_src;
                        dst = (packetbody_t)&ip6->ip6_dst;
                        if (sport > dport)
                                rev = 1;
                        else if (sport == dport) {
                                if (p_memcmp(src, dst, sizeof ip6->ip6_dst) > 0)
                                        rev = 1;
                        }
                        if (rev) {
                                p_memcpy_from_packet(&tha.src, dst, sizeof ip6->ip6_dst);
                                p_memcpy_from_packet(&tha.dst, src, sizeof ip6->ip6_src);
                                tha.port = dport << 16 | sport;
                        } else {
                                p_memcpy_from_packet(&tha.dst, dst, sizeof ip6->ip6_dst);
                                p_memcpy_from_packet(&tha.src, src, sizeof ip6->ip6_src);
                                tha.port = sport << 16 | dport;
                        }
                } else {
                        /*
                         * Zero out the tha structure; the src and dst
                         * fields are big enough to hold an IPv6
                         * address, but we only have IPv4 addresses
                         * and thus must clear out the remaining 124
                         * bits.
                         *
                         * XXX - should we just clear those bytes after
                         * copying the IPv4 addresses, rather than
                         * zeroing out the entire structure and then
                         * overwriting some of the zeroes?
                         *
                         * XXX - this could fail if we see TCP packets
                         * with an IPv6 address with the lower 124 bits
                         * all zero and also see TCP packes with an
                         * IPv4 address with the same 32 bits as the
                         * upper 32 bits of the IPv6 address in question.
                         * Can that happen?  Is it likely enough to be
                         * an issue?
                         */
                        memset(&tha, 0, sizeof(tha));
                        src = (packetbody_t)&ip->ip_src;
                        dst = (packetbody_t)&ip->ip_dst;
                        if (sport > dport)
                                rev = 1;
                        else if (sport == dport) {
                                if (p_memcmp(src, dst, sizeof ip->ip_dst) > 0)
                                        rev = 1;
                        }
                        if (rev) {
                                p_memcpy_from_packet(&tha.src, dst, sizeof ip->ip_dst);
                                p_memcpy_from_packet(&tha.dst, src, sizeof ip->ip_src);
                                tha.port = dport << 16 | sport;
                        } else {
                                p_memcpy_from_packet(&tha.dst, dst, sizeof ip->ip_dst);
                                p_memcpy_from_packet(&tha.src, src, sizeof ip->ip_src);
                                tha.port = sport << 16 | dport;
                        }
                }
#else
                rev = 0;
                src = &ip->ip_src;
                dst = &ip->ip_dst;
                if (sport > dport)
                        rev = 1;
                else if (sport == dport) {
                        if (p_memcmp(src, dst, sizeof ip->ip_dst) > 0)
                                rev = 1;
                }
                if (rev) {
                        memcpy(&tha.src, dst, sizeof ip->ip_dst);
                        memcpy(&tha.dst, src, sizeof ip->ip_src);
                        tha.port = dport << 16 | sport;
                } else {
                        memcpy(&tha.dst, dst, sizeof ip->ip_dst);
                        memcpy(&tha.src, src, sizeof ip->ip_src);
                        tha.port = sport << 16 | dport;
                }
#endif

                threv = rev;
                for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
                     th->nxt; th = th->nxt)
                        if (memcmp((char *)&tha, (char *)&th->addr,
                                   sizeof(th->addr)) == 0)
                                break;

                if (!th->nxt || (flags & TH_SYN)) {
                        /* didn't find it or new conversation */
                        if (th->nxt == NULL) {
                                th->nxt = (struct tcp_seq_hash *)
                                        calloc(1, sizeof(*th));
                                if (th->nxt == NULL)
                                        error("tcp_print: calloc");
                        }
                        th->addr = tha;
                        if (rev)
                                th->ack = seq, th->seq = ack - 1;
                        else
                                th->seq = seq, th->ack = ack - 1;
                } else {
                        if (rev)
                                seq -= th->ack, ack -= th->seq;
                        else
                                seq -= th->seq, ack -= th->ack;
                }

                thseq = th->seq;
                thack = th->ack;
        } else {
                /*fool gcc*/
                thseq = thack = threv = 0;
        }
        if (hlen > length) {
                (void)printf(" [bad hdr length %u - too long, > %u]",
                             hlen, length);
                return;
        }

        if (vflag && !Kflag && !fragmented) {
                /* Check the checksum, if possible. */
                u_int16_t sum, tcp_sum;

                if (IP_V(ip) == 4) {
                        if (PACKET_HAS_SPACE(tp, length)) {
                                sum = tcp_cksum(ip, tp, length);
                                tcp_sum = EXTRACT_16BITS(&tp->th_sum);

                                (void)printf(", cksum 0x%04x", tcp_sum);
                                if (sum != 0)
                                        (void)printf(" (incorrect -> 0x%04x)",
                                            in_cksum_shouldbe(tcp_sum, sum));
                                else
                                        (void)printf(" (correct)");
                        }
                }
#ifdef INET6
                else if (IP_V(ip) == 6 && ip6->ip6_plen) {
                        if (PACKET_HAS_SPACE(tp, length)) {
                                sum = nextproto6_cksum(ip6, (packetbody_t)tp, length, IPPROTO_TCP);
                                tcp_sum = EXTRACT_16BITS(&tp->th_sum);

                                (void)printf(", cksum 0x%04x", tcp_sum);
                                if (sum != 0)
                                        (void)printf(" (incorrect -> 0x%04x)",
                                            in_cksum_shouldbe(tcp_sum, sum));
                                else
                                        (void)printf(" (correct)");

                        }
                }
#endif
        }

        length -= hlen;
        if (vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST)) {
                (void)printf(", seq %u", seq);

                if (length > 0) {
                        (void)printf(":%u", seq + length);
                }
        }

        if (flags & TH_ACK) {
                (void)printf(", ack %u", ack);
        }

        (void)printf(", win %d", win);

        if (flags & TH_URG)
                (void)printf(", urg %d", urp);
        /*
         * Handle any options.
         */
        if (hlen > sizeof(*tp)) {
                packetbody_t cp;
                register u_int i, opt, datalen;
                register u_int len;

                hlen -= sizeof(*tp);
                cp = (packetbody_t)tp + sizeof(*tp);
                printf(", options [");
                while (hlen > 0) {
                        if (ch != '\0')
                                putchar(ch);
                        PACKET_HAS_ONE_OR_TRUNC(cp);
                        opt = *cp++;
                        if (ZEROLENOPT(opt))
                                len = 1;
                        else {
                                PACKET_HAS_ONE_OR_TRUNC(cp);
                                len = *cp++;	/* total including type, len */
                                if (len < 2 || len > hlen)
                                        goto bad;
                                --hlen;		/* account for length byte */
                        }
                        --hlen;			/* account for type byte */
                        datalen = 0;

/* Bail if "l" bytes of data are not left or were not captured  */
#define LENCHECK(l) { if ((l) > hlen) goto bad; PACKET_HAS_SPACE_OR_TRUNC(cp, l); }


                        printf("%s", tok2str(tcp_option_values, "Unknown Option %u", opt));

                        switch (opt) {

                        case TCPOPT_MAXSEG:
                                datalen = 2;
                                LENCHECK(datalen);
                                (void)printf(" %u", EXTRACT_16BITS(cp));
                                break;

                        case TCPOPT_WSCALE:
                                datalen = 1;
                                LENCHECK(datalen);
                                (void)printf(" %u", *cp);
                                break;

                        case TCPOPT_SACK:
                                datalen = len - 2;
                                if (datalen % 8 != 0) {
                                        (void)printf("malformed sack");
                                } else {
                                        u_int32_t s, e;

                                        (void)printf(" %d ", datalen / 8);
                                        for (i = 0; i < datalen; i += 8) {
                                                LENCHECK(i + 4);
                                                s = EXTRACT_32BITS(cp + i);
                                                LENCHECK(i + 8);
                                                e = EXTRACT_32BITS(cp + i + 4);
                                                if (threv) {
                                                        s -= thseq;
                                                        e -= thseq;
                                                } else {
                                                        s -= thack;
                                                        e -= thack;
                                                }
                                                (void)printf("{%u:%u}", s, e);
                                        }
                                }
                                break;

                        case TCPOPT_CC:
                        case TCPOPT_CCNEW:
                        case TCPOPT_CCECHO:
                        case TCPOPT_ECHO:
                        case TCPOPT_ECHOREPLY:

                                /*
                                 * those options share their semantics.
                                 * fall through
                                 */
                                datalen = 4;
                                LENCHECK(datalen);
                                (void)printf(" %u", EXTRACT_32BITS(cp));
                                break;

                        case TCPOPT_TIMESTAMP:
                                datalen = 8;
                                LENCHECK(datalen);
                                (void)printf(" val %u ecr %u",
                                             EXTRACT_32BITS(cp),
                                             EXTRACT_32BITS(cp + 4));
                                break;

                        case TCPOPT_SIGNATURE:
                                datalen = TCP_SIGLEN;
                                LENCHECK(datalen);
#ifdef HAVE_LIBCRYPTO
                                switch (tcp_verify_signature(ip, tp,
                                                             bp + TH_OFF(tp) * 4, length, cp)) {

                                case SIGNATURE_VALID:
                                        (void)printf("valid");
                                        break;

                                case SIGNATURE_INVALID:
                                        (void)printf("invalid");
                                        break;

                                case CANT_CHECK_SIGNATURE:
                                        (void)printf("can't check - ");
                                        for (i = 0; i < TCP_SIGLEN; ++i)
                                                (void)printf("%02x", cp[i]);
                                        break;
                                }
#else
                                for (i = 0; i < TCP_SIGLEN; ++i)
                                        (void)printf("%02x", cp[i]);
#endif
                                break;

                        case TCPOPT_AUTH:
                                (void)printf("keyid %d", *cp++);
                                datalen = len - 3;
                                for (i = 0; i < datalen; ++i) {
                                        LENCHECK(i);
                                        (void)printf("%02x", cp[i]);
                                }
                                break;


                        case TCPOPT_EOL:
                        case TCPOPT_NOP:
                        case TCPOPT_SACKOK:
                                /*
                                 * Nothing interesting.
                                 * fall through
                                 */
                                break;

                        case TCPOPT_UTO:
                                datalen = 2;
                                LENCHECK(datalen);
                                utoval = EXTRACT_16BITS(cp);
                                (void)printf("0x%x", utoval);
                                if (utoval & 0x0001)
                                        utoval = (utoval >> 1) * 60;
                                else
                                        utoval >>= 1;
                                (void)printf(" %u", utoval);
                                break;

                        default:
                                datalen = len - 2;
                                for (i = 0; i < datalen; ++i) {
                                        LENCHECK(i);
                                        (void)printf("%02x", cp[i]);
                                }
                                break;
                        }

                        /* Account for data printed */
                        cp += datalen;
                        hlen -= datalen;

                        /* Check specification against observed length */
                        ++datalen;			/* option octet */
                        if (!ZEROLENOPT(opt))
                                ++datalen;		/* size octet */
                        if (datalen != len)
                                (void)printf("[len %d]", len);
                        ch = ',';
                        if (opt == TCPOPT_EOL)
                                break;
                }