Update tcpdump to 4.9.0.

It fixes many buffer overflow in different protocol parsers, but none of
them are critical, even in absense of Capsicum.

Security:	CVE-2016-7922, CVE-2016-7923, CVE-2016-7924, CVE-2016-7925
Security:	CVE-2016-7926, CVE-2016-7927, CVE-2016-7928, CVE-2016-7929
Security:	CVE-2016-7930, CVE-2016-7931, CVE-2016-7932, CVE-2016-7933
Security:	CVE-2016-7934, CVE-2016-7935, CVE-2016-7936, CVE-2016-7937
Security:	CVE-2016-7938, CVE-2016-7939, CVE-2016-7940, CVE-2016-7973
Security:	CVE-2016-7974, CVE-2016-7975, CVE-2016-7983, CVE-2016-7984
Security:	CVE-2016-7985, CVE-2016-7986, CVE-2016-7992, CVE-2016-7993
Security:	CVE-2016-8574, CVE-2016-8575, CVE-2017-5202, CVE-2017-5203
Security:	CVE-2017-5204, CVE-2017-5205, CVE-2017-5341, CVE-2017-5342
Security:	CVE-2017-5482, CVE-2017-5483, CVE-2017-5484, CVE-2017-5485
Security:	CVE-2017-5486

1 files changed, 152 insertions, 129 deletions

diff --git a/contrib/tcpdump/print-tcp.c b/contrib/tcpdump/print-tcp.c
index a5c70477a8fb..e0d0531b36b2 100644
--- a/contrib/tcpdump/print-tcp.c
+++ b/contrib/tcpdump/print-tcp.c
@@ -23,40 +23,37 @@
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  */
 
+/* \summary: TCP printer */
+
 #ifndef lint
 #else
 __RCSID("$NetBSD: print-tcp.c,v 1.8 2007/07/24 11:53:48 drochner Exp $");
 #endif
 
-#define NETDISSECT_REWORKED
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include <tcpdump-stdinc.h>
+#include <netdissect-stdinc.h>
 
 #include <stdlib.h>
 #include <string.h>
 
-#include "interface.h"
+#include "netdissect.h"
 #include "addrtoname.h"
 #include "extract.h"
 
 #include "tcp.h"
 
 #include "ip.h"
-#ifdef INET6
 #include "ip6.h"
-#endif
 #include "ipproto.h"
 #include "rpc_auth.h"
 #include "rpc_msg.h"
 
-#include "nameser.h"
-
 #ifdef HAVE_LIBCRYPTO
 #include <openssl/md5.h>
-#include <signature.h>
+#include "signature.h"
 
 static int tcp_verify_signature(netdissect_options *ndo,
                                 const struct ip *ip, const struct tcphdr *tp,
@@ -64,6 +61,8 @@ static int tcp_verify_signature(netdissect_options *ndo,
 #endif
 
 static void print_tcp_rst_data(netdissect_options *, register const u_char *sp, u_int length);
+static void print_tcp_fastopen_option(netdissect_options *ndo, register const u_char *cp,
+                                      u_int datalen, int exp);
 
 #define MAX_RST_DATA_LEN	30
 
@@ -81,7 +80,6 @@ struct tcp_seq_hash {
         tcp_seq ack;
 };
 
-#ifdef INET6
 struct tha6 {
         struct in6_addr src;
         struct in6_addr dst;
@@ -94,7 +92,6 @@ struct tcp_seq_hash6 {
         tcp_seq seq;
         tcp_seq ack;
 };
-#endif
 
 #define TSEQ_HASHSIZE 919
 
@@ -102,9 +99,7 @@ struct tcp_seq_hash6 {
 #define ZEROLENOPT(o) ((o) == TCPOPT_EOL || (o) == TCPOPT_NOP)
 
 static struct tcp_seq_hash tcp_seq_hash4[TSEQ_HASHSIZE];
-#ifdef INET6
 static struct tcp_seq_hash6 tcp_seq_hash6[TSEQ_HASHSIZE];
-#endif
 
 static const struct tok tcp_flag_values[] = {
         { TH_FIN, "F" },
@@ -132,9 +127,11 @@ static const struct tok tcp_option_values[] = {
         { TCPOPT_CCNEW, "ccnew" },
         { TCPOPT_CCECHO, "" },
         { TCPOPT_SIGNATURE, "md5" },
-        { TCPOPT_AUTH, "enhanced auth" },
+        { TCPOPT_SCPS, "scps" },
         { TCPOPT_UTO, "uto" },
+        { TCPOPT_TCPAO, "tcp-ao" },
         { TCPOPT_MPTCP, "mptcp" },
+        { TCPOPT_FASTOPEN, "tfo" },
         { TCPOPT_EXPERIMENT2, "exp" },
         { 0, NULL }
 };
@@ -149,6 +146,16 @@ tcp_cksum(netdissect_options *ndo,
 				IPPROTO_TCP);
 }
 
+static int
+tcp6_cksum(netdissect_options *ndo,
+           register const struct ip6_hdr *ip6,
+           register const struct tcphdr *tp,
+           register u_int len)
+{
+	return nextproto6_cksum(ndo, ip6, (const uint8_t *)tp, len, len,
+				IPPROTO_TCP);
+}
+
 void
 tcp_print(netdissect_options *ndo,
           register const u_char *bp, register u_int length,
@@ -164,18 +171,14 @@ tcp_print(netdissect_options *ndo,
         u_int utoval;
         uint16_t magic;
         register int rev;
-#ifdef INET6
         register const struct ip6_hdr *ip6;
-#endif
 
-        tp = (struct tcphdr *)bp;
-        ip = (struct ip *)bp2;
-#ifdef INET6
+        tp = (const struct tcphdr *)bp;
+        ip = (const struct ip *)bp2;
         if (IP_V(ip) == 6)
-                ip6 = (struct ip6_hdr *)bp2;
+                ip6 = (const struct ip6_hdr *)bp2;
         else
                 ip6 = NULL;
-#endif /*INET6*/
         ch = '\0';
         if (!ND_TTEST(tp->th_dport)) {
                 ND_PRINT((ndo, "%s > %s: [|tcp]",
@@ -187,43 +190,40 @@ tcp_print(netdissect_options *ndo,
         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) {
                         ND_PRINT((ndo, "%s.%s > %s.%s: ",
                                      ip6addr_string(ndo, &ip6->ip6_src),
-                                     tcpport_string(sport),
+                                     tcpport_string(ndo, sport),
                                      ip6addr_string(ndo, &ip6->ip6_dst),
-                                     tcpport_string(dport)));
+                                     tcpport_string(ndo, dport)));
                 } else {
                         ND_PRINT((ndo, "%s > %s: ",
-                                     tcpport_string(sport), tcpport_string(dport)));
+                                     tcpport_string(ndo, sport), tcpport_string(ndo, dport)));
                 }
-        } else
-#endif /*INET6*/
-        {
+        } else {
                 if (ip->ip_p == IPPROTO_TCP) {
                         ND_PRINT((ndo, "%s.%s > %s.%s: ",
                                      ipaddr_string(ndo, &ip->ip_src),
-                                     tcpport_string(sport),
+                                     tcpport_string(ndo, sport),
                                      ipaddr_string(ndo, &ip->ip_dst),
-                                     tcpport_string(dport)));
+                                     tcpport_string(ndo, dport)));
                 } else {
                         ND_PRINT((ndo, "%s > %s: ",
-                                     tcpport_string(sport), tcpport_string(dport)));
+                                     tcpport_string(ndo, sport), tcpport_string(ndo, dport)));
                 }
         }
 
+        ND_TCHECK(*tp);
+
+        hlen = TH_OFF(tp) * 4;
+
         if (hlen < sizeof(*tp)) {
                 ND_PRINT((ndo, " tcp %d [bad hdr length %u - too short, < %lu]",
                              length - hlen, hlen, (unsigned long)sizeof(*tp)));
                 return;
         }
 
-        ND_TCHECK(*tp);
-
         seq = EXTRACT_32BITS(&tp->th_seq);
         ack = EXTRACT_32BITS(&tp->th_ack);
         win = EXTRACT_16BITS(&tp->th_win);
@@ -249,11 +249,10 @@ tcp_print(netdissect_options *ndo,
                  * both directions).
                  */
                 rev = 0;
-#ifdef INET6
                 if (ip6) {
                         register struct tcp_seq_hash6 *th;
                         struct tcp_seq_hash6 *tcp_seq_hash;
-                        const void *src, *dst;
+                        const struct in6_addr *src, *dst;
                         struct tha6 tha;
 
                         tcp_seq_hash = tcp_seq_hash6;
@@ -287,7 +286,8 @@ tcp_print(netdissect_options *ndo,
                                         th->nxt = (struct tcp_seq_hash6 *)
                                                 calloc(1, sizeof(*th));
                                         if (th->nxt == NULL)
-                                                error("tcp_print: calloc");
+                                                (*ndo->ndo_error)(ndo,
+								  "tcp_print: calloc");
                                 }
                                 th->addr = tha;
                                 if (rev)
@@ -304,30 +304,24 @@ tcp_print(netdissect_options *ndo,
                         thseq = th->seq;
                         thack = th->ack;
                 } else {
-#else  /*INET6*/
-                {
-#endif /*INET6*/
                         register struct tcp_seq_hash *th;
                         struct tcp_seq_hash *tcp_seq_hash;
-                        const void *src, *dst;
                         struct tha tha;
 
                         tcp_seq_hash = tcp_seq_hash4;
-                        src = &ip->ip_src;
-                        dst = &ip->ip_dst;
                         if (sport > dport)
                                 rev = 1;
                         else if (sport == dport) {
-                                if (UNALIGNED_MEMCMP(src, dst, sizeof ip->ip_dst) > 0)
+                                if (UNALIGNED_MEMCMP(&ip->ip_src, &ip->ip_dst, sizeof ip->ip_dst) > 0)
                                         rev = 1;
                         }
                         if (rev) {
-                                UNALIGNED_MEMCPY(&tha.src, dst, sizeof ip->ip_dst);
-                                UNALIGNED_MEMCPY(&tha.dst, src, sizeof ip->ip_src);
+                                UNALIGNED_MEMCPY(&tha.src, &ip->ip_dst, sizeof ip->ip_dst);
+                                UNALIGNED_MEMCPY(&tha.dst, &ip->ip_src, sizeof ip->ip_src);
                                 tha.port = dport << 16 | sport;
                         } else {
-                                UNALIGNED_MEMCPY(&tha.dst, dst, sizeof ip->ip_dst);
-                                UNALIGNED_MEMCPY(&tha.src, src, sizeof ip->ip_src);
+                                UNALIGNED_MEMCPY(&tha.dst, &ip->ip_dst, sizeof ip->ip_dst);
+                                UNALIGNED_MEMCPY(&tha.src, &ip->ip_src, sizeof ip->ip_src);
                                 tha.port = sport << 16 | dport;
                         }
 
@@ -343,7 +337,8 @@ tcp_print(netdissect_options *ndo,
                                         th->nxt = (struct tcp_seq_hash *)
                                                 calloc(1, sizeof(*th));
                                         if (th->nxt == NULL)
-                                                error("tcp_print: calloc");
+                                                (*ndo->ndo_error)(ndo,
+								  "tcp_print: calloc");
                                 }
                                 th->addr = tha;
                                 if (rev)
@@ -386,12 +381,9 @@ tcp_print(netdissect_options *ndo,
                                 else
                                         ND_PRINT((ndo, " (correct)"));
                         }
-                }
-#ifdef INET6
-                else if (IP_V(ip) == 6 && ip6->ip6_plen) {
+                } else if (IP_V(ip) == 6 && ip6->ip6_plen) {
                         if (ND_TTEST2(tp->th_sport, length)) {
-                                sum = nextproto6_cksum(ip6, (const uint8_t *)tp,
-							length, length, IPPROTO_TCP);
+                                sum = tcp6_cksum(ndo, ip6, tp, length);
                                 tcp_sum = EXTRACT_16BITS(&tp->th_sum);
 
                                 ND_PRINT((ndo, ", cksum 0x%04x", tcp_sum));
@@ -403,7 +395,6 @@ tcp_print(netdissect_options *ndo,
 
                         }
                 }
-#endif
         }
 
         length -= hlen;
@@ -474,7 +465,7 @@ tcp_print(netdissect_options *ndo,
                         case TCPOPT_SACK:
                                 datalen = len - 2;
                                 if (datalen % 8 != 0) {
-                                        ND_PRINT((ndo, "malformed sack"));
+                                        ND_PRINT((ndo, " invalid sack"));
                                 } else {
                                         uint32_t s, e;
 
@@ -522,6 +513,7 @@ tcp_print(netdissect_options *ndo,
                         case TCPOPT_SIGNATURE:
                                 datalen = TCP_SIGLEN;
                                 LENCHECK(datalen);
+                                ND_PRINT((ndo, " "));
 #ifdef HAVE_LIBCRYPTO
                                 switch (tcp_verify_signature(ndo, ip, tp,
                                                              bp + TH_OFF(tp) * 4, length, cp)) {
@@ -546,15 +538,35 @@ tcp_print(netdissect_options *ndo,
 #endif
                                 break;
 
-                        case TCPOPT_AUTH:
-                                ND_PRINT((ndo, "keyid %d", *cp++));
-                                datalen = len - 3;
-                                for (i = 0; i < datalen; ++i) {
-                                        LENCHECK(i);
-                                        ND_PRINT((ndo, "%02x", cp[i]));
-                                }
+                        case TCPOPT_SCPS:
+                                datalen = 2;
+                                LENCHECK(datalen);
+                                ND_PRINT((ndo, " cap %02x id %u", cp[0], cp[1]));
                                 break;
 
+                        case TCPOPT_TCPAO:
+                                datalen = len - 2;
+                                /* RFC 5925 Section 2.2:
+                                 * "The Length value MUST be greater than or equal to 4."
+                                 * (This includes the Kind and Length fields already processed
+                                 * at this point.)
+                                 */
+                                if (datalen < 2) {
+                                        ND_PRINT((ndo, " invalid"));
+                                } else {
+                                        LENCHECK(1);
+                                        ND_PRINT((ndo, " keyid %u", cp[0]));
+                                        LENCHECK(2);
+                                        ND_PRINT((ndo, " rnextkeyid %u", cp[1]));
+                                        if (datalen > 2) {
+                                                ND_PRINT((ndo, " mac 0x"));
+                                                for (i = 2; i < datalen; i++) {
+                                                        LENCHECK(i + 1);
+                                                        ND_PRINT((ndo, "%02x", cp[i]));
+                                                }
+                                        }
+                                }
+                                break;
 
                         case TCPOPT_EOL:
                         case TCPOPT_NOP:
@@ -569,7 +581,7 @@ tcp_print(netdissect_options *ndo,
                                 datalen = 2;
                                 LENCHECK(datalen);
                                 utoval = EXTRACT_16BITS(cp);
-                                ND_PRINT((ndo, "0x%x", utoval));
+                                ND_PRINT((ndo, " 0x%x", utoval));
                                 if (utoval & 0x0001)
                                         utoval = (utoval >> 1) * 60;
                                 else
@@ -584,6 +596,13 @@ tcp_print(netdissect_options *ndo,
                                         goto bad;
                                 break;
 
+                        case TCPOPT_FASTOPEN:
+                                datalen = len - 2;
+                                LENCHECK(datalen);
+                                ND_PRINT((ndo, " "));
+                                print_tcp_fastopen_option(ndo, cp, datalen, FALSE);
+                                break;
+
                         case TCPOPT_EXPERIMENT2:
                                 datalen = len - 2;
                                 LENCHECK(datalen);
@@ -595,21 +614,8 @@ tcp_print(netdissect_options *ndo,
 
                                 switch(magic) {
 
-                                case 0xf989:
-                                        /* TCP Fast Open: RFC 7413 */
-                                        if (datalen == 2) {
-                                                /* Fast Open Cookie Request */
-                                                ND_PRINT((ndo, "tfo cookiereq"));
-                                        } else {
-                                                /* Fast Open Cookie */
-                                                if (datalen % 2 != 0 || datalen < 6 || datalen > 18) {
-                                                        ND_PRINT((ndo, "tfo malformed"));
-                                                } else {
-                                                        ND_PRINT((ndo, "tfo cookie "));
-                                                        for (i = 2; i < datalen; ++i)
-                                                                ND_PRINT((ndo, "%02x", cp[i]));
-                                                }
-                                        }
+                                case 0xf989: /* TCP Fast Open RFC 7413 */
+                                        print_tcp_fastopen_option(ndo, cp + 2, datalen - 2, TRUE);
                                         break;
 
                                 default:
@@ -624,7 +630,7 @@ tcp_print(netdissect_options *ndo,
                                 if (datalen)
                                         ND_PRINT((ndo, " 0x"));
                                 for (i = 0; i < datalen; ++i) {
-                                        LENCHECK(i);
+                                        LENCHECK(i + 1);
                                         ND_PRINT((ndo, "%02x", cp[i]));
                                 }
                                 break;
@@ -669,58 +675,59 @@ tcp_print(netdissect_options *ndo,
                 case PT_ZMTP1:
                         zmtp1_print(ndo, bp, length);
                         break;
+                case PT_RESP:
+                        resp_print(ndo, bp, length);
+                        break;
                 }
                 return;
         }
 
-        if (sport == TELNET_PORT || dport == TELNET_PORT) {
+        if (IS_SRC_OR_DST_PORT(TELNET_PORT)) {
                 telnet_print(ndo, bp, length);
-        } else if (sport == SMTP_PORT || dport == SMTP_PORT) {
+        } else if (IS_SRC_OR_DST_PORT(SMTP_PORT)) {
                 ND_PRINT((ndo, ": "));
                 smtp_print(ndo, bp, length);
-        } else if (sport == BGP_PORT || dport == BGP_PORT)
+        } else if (IS_SRC_OR_DST_PORT(BGP_PORT))
                 bgp_print(ndo, bp, length);
-        else if (sport == PPTP_PORT || dport == PPTP_PORT)
+        else if (IS_SRC_OR_DST_PORT(PPTP_PORT))
                 pptp_print(ndo, bp);
-#ifdef TCPDUMP_DO_SMB
-        else if (sport == NETBIOS_SSN_PORT || dport == NETBIOS_SSN_PORT)
+        else if (IS_SRC_OR_DST_PORT(REDIS_PORT))
+                resp_print(ndo, bp, length);
+#ifdef ENABLE_SMB
+        else if (IS_SRC_OR_DST_PORT(NETBIOS_SSN_PORT))
                 nbt_tcp_print(ndo, bp, length);
-	else if (sport == SMB_PORT || dport == SMB_PORT)
+	else if (IS_SRC_OR_DST_PORT(SMB_PORT))
 		smb_tcp_print(ndo, bp, length);
 #endif
-        else if (sport == BEEP_PORT || dport == BEEP_PORT)
+        else if (IS_SRC_OR_DST_PORT(BEEP_PORT))
                 beep_print(ndo, bp, length);
-        else if (sport == OPENFLOW_PORT_OLD || dport == OPENFLOW_PORT_OLD ||
-                 sport == OPENFLOW_PORT_IANA || dport == OPENFLOW_PORT_IANA)
+        else if (IS_SRC_OR_DST_PORT(OPENFLOW_PORT_OLD) || IS_SRC_OR_DST_PORT(OPENFLOW_PORT_IANA))
                 openflow_print(ndo, bp, length);
-        else if (sport == FTP_PORT || dport == FTP_PORT) {
+        else if (IS_SRC_OR_DST_PORT(FTP_PORT)) {
                 ND_PRINT((ndo, ": "));
                 ftp_print(ndo, bp, length);
-        } else if (sport == HTTP_PORT || dport == HTTP_PORT ||
-            sport == HTTP_PORT_ALT || dport == HTTP_PORT_ALT) {
+        } else if (IS_SRC_OR_DST_PORT(HTTP_PORT) || IS_SRC_OR_DST_PORT(HTTP_PORT_ALT)) {
                 ND_PRINT((ndo, ": "));
                 http_print(ndo, bp, length);
-        } else if (sport == RTSP_PORT || dport == RTSP_PORT ||
-            sport == RTSP_PORT_ALT || dport == RTSP_PORT_ALT) {
+        } else if (IS_SRC_OR_DST_PORT(RTSP_PORT) || IS_SRC_OR_DST_PORT(RTSP_PORT_ALT)) {
                 ND_PRINT((ndo, ": "));
                 rtsp_print(ndo, bp, length);
         } else if (length > 2 &&
-                 (sport == NAMESERVER_PORT || dport == NAMESERVER_PORT ||
-                  sport == MULTICASTDNS_PORT || dport == MULTICASTDNS_PORT)) {
+                 (IS_SRC_OR_DST_PORT(NAMESERVER_PORT))) {
                 /*
                  * TCP DNS query has 2byte length at the head.
                  * XXX packet could be unaligned, it can go strange
                  */
                 ns_print(ndo, bp + 2, length - 2, 0);
-        } else if (sport == MSDP_PORT || dport == MSDP_PORT) {
+        } else if (IS_SRC_OR_DST_PORT(MSDP_PORT)) {
                 msdp_print(ndo, bp, length);
-        } else if (sport == RPKI_RTR_PORT || dport == RPKI_RTR_PORT) {
+        } else if (IS_SRC_OR_DST_PORT(RPKI_RTR_PORT)) {
                 rpki_rtr_print(ndo, bp, length);
         }
-        else if (length > 0 && (sport == LDP_PORT || dport == LDP_PORT)) {
+        else if (length > 0 && (IS_SRC_OR_DST_PORT(LDP_PORT))) {
                 ldp_print(ndo, bp, length);
         }
-        else if ((sport == NFS_PORT || dport == NFS_PORT) &&
+        else if ((IS_SRC_OR_DST_PORT(NFS_PORT)) &&
                  length >= 4 && ND_TTEST2(*bp, 4)) {
                 /*
                  * If data present, header length valid, and NFS port used,
@@ -729,23 +736,23 @@ tcp_print(netdissect_options *ndo,
                  * to NFS print routines.
                  */
                 uint32_t fraglen;
-                register struct sunrpc_msg *rp;
+                register const struct sunrpc_msg *rp;
                 enum sunrpc_msg_type direction;
 
                 fraglen = EXTRACT_32BITS(bp) & 0x7FFFFFFF;
                 if (fraglen > (length) - 4)
                         fraglen = (length) - 4;
-                rp = (struct sunrpc_msg *)(bp + 4);
+                rp = (const struct sunrpc_msg *)(bp + 4);
                 if (ND_TTEST(rp->rm_direction)) {
                         direction = (enum sunrpc_msg_type)EXTRACT_32BITS(&rp->rm_direction);
                         if (dport == NFS_PORT && direction == SUNRPC_CALL) {
                                 ND_PRINT((ndo, ": NFS request xid %u ", EXTRACT_32BITS(&rp->rm_xid)));
-                                nfsreq_print_noaddr(ndo, (u_char *)rp, fraglen, (u_char *)ip);
+                                nfsreq_print_noaddr(ndo, (const u_char *)rp, fraglen, (const u_char *)ip);
                                 return;
                         }
                         if (sport == NFS_PORT && direction == SUNRPC_REPLY) {
                                 ND_PRINT((ndo, ": NFS reply xid %u ", EXTRACT_32BITS(&rp->rm_xid)));
-                                nfsreply_print_noaddr(ndo, (u_char *)rp, fraglen, (u_char *)ip);
+                                nfsreply_print_noaddr(ndo, (const u_char *)rp, fraglen, (const u_char *)ip);
                                 return;
                         }
                 }
@@ -790,13 +797,37 @@ print_tcp_rst_data(netdissect_options *ndo,
                 ND_PRINT((ndo, "+"));			/* indicate we truncate */
         }
         ND_PRINT((ndo, " "));
-        while (length-- && sp <= ndo->ndo_snapend) {
+        while (length-- && sp < ndo->ndo_snapend) {
                 c = *sp++;
                 safeputchar(ndo, c);
         }
         ND_PRINT((ndo, "]"));
 }
 
+static void
+print_tcp_fastopen_option(netdissect_options *ndo, register const u_char *cp,
+                          u_int datalen, int exp)
+{
+        u_int i;
+
+        if (exp)
+                ND_PRINT((ndo, "tfo"));
+
+        if (datalen == 0) {
+                /* Fast Open Cookie Request */
+                ND_PRINT((ndo, " cookiereq"));
+        } else {
+                /* Fast Open Cookie */
+                if (datalen % 2 != 0 || datalen < 4 || datalen > 16) {
+                        ND_PRINT((ndo, " invalid"));
+                } else {
+                        ND_PRINT((ndo, " cookie "));
+                        for (i = 0; i < datalen; ++i)
+                                ND_PRINT((ndo, "%02x", cp[i]));
+                }
+        }
+}
+
 #ifdef HAVE_LIBCRYPTO
 USES_APPLE_DEPRECATED_API
 static int
@@ -809,11 +840,9 @@ tcp_verify_signature(netdissect_options *ndo,
         char zero_proto = 0;
         MD5_CTX ctx;
         uint16_t savecsum, tlen;
-#ifdef INET6
-        struct ip6_hdr *ip6;
+        const struct ip6_hdr *ip6;
         uint32_t len32;
         uint8_t nxt;
-#endif
 
 	if (data + length > ndo->ndo_snapend) {
 		ND_PRINT((ndo, "snaplen too short, "));
@@ -832,33 +861,27 @@ tcp_verify_signature(netdissect_options *ndo,
          * Step 1: Update MD5 hash with IP pseudo-header.
          */
         if (IP_V(ip) == 4) {
-                MD5_Update(&ctx, (char *)&ip->ip_src, sizeof(ip->ip_src));
-                MD5_Update(&ctx, (char *)&ip->ip_dst, sizeof(ip->ip_dst));
-                MD5_Update(&ctx, (char *)&zero_proto, sizeof(zero_proto));
-                MD5_Update(&ctx, (char *)&ip->ip_p, sizeof(ip->ip_p));
+                MD5_Update(&ctx, (const char *)&ip->ip_src, sizeof(ip->ip_src));
+                MD5_Update(&ctx, (const char *)&ip->ip_dst, sizeof(ip->ip_dst));
+                MD5_Update(&ctx, (const char *)&zero_proto, sizeof(zero_proto));
+                MD5_Update(&ctx, (const char *)&ip->ip_p, sizeof(ip->ip_p));
                 tlen = EXTRACT_16BITS(&ip->ip_len) - IP_HL(ip) * 4;
                 tlen = htons(tlen);
-                MD5_Update(&ctx, (char *)&tlen, sizeof(tlen));
-#ifdef INET6
+                MD5_Update(&ctx, (const char *)&tlen, sizeof(tlen));
         } else if (IP_V(ip) == 6) {
-                ip6 = (struct ip6_hdr *)ip;
-                MD5_Update(&ctx, (char *)&ip6->ip6_src, sizeof(ip6->ip6_src));
-                MD5_Update(&ctx, (char *)&ip6->ip6_dst, sizeof(ip6->ip6_dst));
+                ip6 = (const struct ip6_hdr *)ip;
+                MD5_Update(&ctx, (const char *)&ip6->ip6_src, sizeof(ip6->ip6_src));
+                MD5_Update(&ctx, (const char *)&ip6->ip6_dst, sizeof(ip6->ip6_dst));
                 len32 = htonl(EXTRACT_16BITS(&ip6->ip6_plen));
-                MD5_Update(&ctx, (char *)&len32, sizeof(len32));
+                MD5_Update(&ctx, (const char *)&len32, sizeof(len32));
                 nxt = 0;
-                MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
-                MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
-                MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
+                MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt));
+                MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt));
+                MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt));
                 nxt = IPPROTO_TCP;
-                MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
-#endif
+                MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt));
         } else {
-#ifdef INET6
 		ND_PRINT((ndo, "IP version not 4 or 6, "));
-#else
-		ND_PRINT((ndo, "IP version not 4, "));
-#endif
                 return (CANT_CHECK_SIGNATURE);
         }
 
@@ -868,7 +891,7 @@ tcp_verify_signature(netdissect_options *ndo,
          */
         savecsum = tp1.th_sum;
         tp1.th_sum = 0;
-        MD5_Update(&ctx, (char *)&tp1, sizeof(struct tcphdr));
+        MD5_Update(&ctx, (const char *)&tp1, sizeof(struct tcphdr));
         tp1.th_sum = savecsum;
         /*
          * Step 3: Update MD5 hash with TCP segment data, if present.