X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/ed85e20e4d6a27d5405f37366dd34b64c10a9211..a7a76012a129ffefb64f102948db63fbc715e45e:/print-ospf6.c

diff --git a/print-ospf6.c b/print-ospf6.c
index b85cfaa0..3b77000f 100644
--- a/print-ospf6.c
+++ b/print-ospf6.c
@@ -21,16 +21,17 @@
  * OSPF support contributed by Jeffrey Honig (jch@mitchell.cit.cornell.edu)
  */
 
-#define NETDISSECT_REWORKED
+/* \summary: IPv6 Open Shortest Path First (OSPFv3) printer */
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include <tcpdump-stdinc.h>
+#include <netdissect-stdinc.h>
 
 #include <string.h>
 
-#include "interface.h"
+#include "netdissect.h"
 #include "addrtoname.h"
 #include "extract.h"
 
@@ -235,60 +236,53 @@ struct ospf6hdr {
     uint16_t ospf6_chksum;
     uint8_t ospf6_instanceid;
     uint8_t ospf6_rsvd;
-    union {
+};
 
-	/* Hello packet */
-	struct {
-	    uint32_t hello_ifid;
-	    union {
-		uint8_t pri;
-		uint32_t opt;
-	    } hello_priandopt;
+/*
+ * The OSPF6 header length is 16 bytes, regardless of how your compiler
+ * might choose to pad the above structure.
+ */
+#define OSPF6HDR_LEN    16
+
+/* Hello packet */
+struct hello6 {
+    uint32_t hello_ifid;
+    union {
+	uint8_t pri;
+	uint32_t opt;
+    } hello_priandopt;
 #define hello_priority	hello_priandopt.pri
 #define hello_options	hello_priandopt.opt
-	    uint16_t hello_helloint;
-	    uint16_t hello_deadint;
-	    rtrid_t hello_dr;
-	    rtrid_t hello_bdr;
-	    rtrid_t hello_neighbor[1]; /* may repeat	*/
-	} un_hello;
-
-	/* Database Description packet */
-	struct {
-	    uint32_t db_options;
-	    uint16_t db_mtu;
-	    uint8_t db_mbz;
-	    uint8_t db_flags;
-	    uint32_t db_seq;
-	    struct lsa6_hdr db_lshdr[1]; /* may repeat	*/
-	} un_db;
-
-	/* Link State Request */
-	struct lsr6 {
-	    uint16_t ls_mbz;
-	    uint16_t ls_type;
-	    rtrid_t ls_stateid;
-	    rtrid_t ls_router;
-	} un_lsr[1];		/* may repeat	*/
-
-	/* Link State Update */
-	struct {
-	    uint32_t lsu_count;
-	    struct lsa6 lsu_lsa[1]; /* may repeat	*/
-	} un_lsu;
+    uint16_t hello_helloint;
+    uint16_t hello_deadint;
+    rtrid_t hello_dr;
+    rtrid_t hello_bdr;
+    rtrid_t hello_neighbor[1]; /* may repeat	*/
+};
 
-	/* Link State Acknowledgement */
-	struct {
-	    struct lsa6_hdr lsa_lshdr[1]; /* may repeat	*/
-	} un_lsa ;
-    } ospf6_un ;
+/* Database Description packet */
+struct dd6 {
+    uint32_t db_options;
+    uint16_t db_mtu;
+    uint8_t db_mbz;
+    uint8_t db_flags;
+    uint32_t db_seq;
+    struct lsa6_hdr db_lshdr[1]; /* may repeat	*/
 };
 
-#define	ospf6_hello	ospf6_un.un_hello
-#define	ospf6_db	ospf6_un.un_db
-#define	ospf6_lsr	ospf6_un.un_lsr
-#define	ospf6_lsu	ospf6_un.un_lsu
-#define	ospf6_lsa	ospf6_un.un_lsa
+/* Link State Request */
+struct lsr6 {
+    uint16_t ls_mbz;
+    uint16_t ls_type;
+    rtrid_t ls_stateid;
+    rtrid_t ls_router;
+};
+
+/* Link State Update */
+struct lsu6 {
+    uint32_t lsu_count;
+    struct lsa6 lsu_lsa[1]; /* may repeat	*/
+};
 
 static const char tstr[] = " [|ospf3]";
 
@@ -393,18 +387,19 @@ static int
 ospf6_print_lshdr(netdissect_options *ndo,
                   register const struct lsa6_hdr *lshp, const u_char *dataend)
 {
-	if ((u_char *)(lshp + 1) > dataend)
+	if ((const u_char *)(lshp + 1) > dataend)
 		goto trunc;
 	ND_TCHECK(lshp->ls_type);
 	ND_TCHECK(lshp->ls_seq);
 
 	ND_PRINT((ndo, "\n\t  Advertising Router %s, seq 0x%08x, age %us, length %u",
                ipaddr_string(ndo, &lshp->ls_router),
-               EXTRACT_32BITS(&lshp->ls_seq),
-               EXTRACT_16BITS(&lshp->ls_age),
-               EXTRACT_16BITS(&lshp->ls_length)-(u_int)sizeof(struct lsa6_hdr)));
+               EXTRACT_BE_32BITS(&lshp->ls_seq),
+               EXTRACT_BE_16BITS(&lshp->ls_age),
+               EXTRACT_BE_16BITS(&lshp->ls_length)-(u_int)sizeof(struct lsa6_hdr)));
 
-	ospf6_print_ls_type(ndo, EXTRACT_16BITS(&lshp->ls_type), &lshp->ls_stateid);
+	ospf6_print_ls_type(ndo, EXTRACT_BE_16BITS(&lshp->ls_type),
+			    &lshp->ls_stateid);
 
 	return (0);
 trunc:
@@ -415,7 +410,7 @@ static int
 ospf6_print_lsaprefix(netdissect_options *ndo,
                       const uint8_t *tptr, u_int lsa_length)
 {
-	const struct lsa6_prefix *lsapp = (struct lsa6_prefix *)tptr;
+	const struct lsa6_prefix *lsapp = (const struct lsa6_prefix *)tptr;
 	u_int wordlen;
 	struct in6_addr prefix;
 
@@ -441,7 +436,7 @@ ospf6_print_lsaprefix(netdissect_options *ndo,
                    bittok2str(ospf6_lsa_prefix_option_values,
                               "none", lsapp->lsa_p_opt)));
         }
-        ND_PRINT((ndo, ", metric %u", EXTRACT_16BITS(&lsapp->lsa_p_metric)));
+        ND_PRINT((ndo, ", metric %u", EXTRACT_BE_16BITS(&lsapp->lsa_p_metric)));
 	return sizeof(*lsapp) - IPV6_ADDR_LEN_BYTES + wordlen * 4;
 
 trunc:
@@ -479,7 +474,7 @@ ospf6_print_lsa(netdissect_options *ndo,
 	if (ospf6_print_lshdr(ndo, &lsap->ls_hdr, dataend))
 		return (1);
 	ND_TCHECK(lsap->ls_hdr.ls_length);
-        length = EXTRACT_16BITS(&lsap->ls_hdr.ls_length);
+        length = EXTRACT_BE_16BITS(&lsap->ls_hdr.ls_length);
 
 	/*
 	 * The LSA length includes the length of the header;
@@ -487,12 +482,12 @@ ospf6_print_lsa(netdissect_options *ndo,
 	 * If it does, find the length of what follows the
 	 * header.
 	 */
-        if (length < sizeof(struct lsa6_hdr) || (u_char *)lsap + length > dataend)
+        if (length < sizeof(struct lsa6_hdr) || (const u_char *)lsap + length > dataend)
         	return (1);
         lsa_length = length - sizeof(struct lsa6_hdr);
-        tptr = (uint8_t *)lsap+sizeof(struct lsa6_hdr);
+        tptr = (const uint8_t *)lsap+sizeof(struct lsa6_hdr);
 
-	switch (EXTRACT_16BITS(&lsap->ls_hdr.ls_type)) {
+	switch (EXTRACT_BE_16BITS(&lsap->ls_hdr.ls_type)) {
 	case LS_TYPE_ROUTER | LS_SCOPE_AREA:
 		if (lsa_length < sizeof (lsap->lsa_un.un_rla.rla_options))
 			return (1);
@@ -500,7 +495,7 @@ ospf6_print_lsa(netdissect_options *ndo,
 		ND_TCHECK(lsap->lsa_un.un_rla.rla_options);
 		ND_PRINT((ndo, "\n\t      Options [%s]",
 		          bittok2str(ospf6_option_values, "none",
-		          EXTRACT_32BITS(&lsap->lsa_un.un_rla.rla_options))));
+		          EXTRACT_BE_32BITS(&lsap->lsa_un.un_rla.rla_options))));
 		ND_PRINT((ndo, ", RLA-Flags [%s]",
 		          bittok2str(ospf6_rla_flag_values, "none",
 		          lsap->lsa_un.un_rla.rla_flags)));
@@ -542,7 +537,7 @@ ospf6_print_lsa(netdissect_options *ndo,
 				    rlp->link_type));
 				return (0);
 			}
-			ND_PRINT((ndo, ", metric %d", EXTRACT_16BITS(&rlp->link_metric)));
+			ND_PRINT((ndo, ", metric %d", EXTRACT_BE_16BITS(&rlp->link_metric)));
 			rlp++;
 		}
 		break;
@@ -554,7 +549,7 @@ ospf6_print_lsa(netdissect_options *ndo,
 		ND_TCHECK(lsap->lsa_un.un_nla.nla_options);
 		ND_PRINT((ndo, "\n\t      Options [%s]",
 		          bittok2str(ospf6_option_values, "none",
-		          EXTRACT_32BITS(&lsap->lsa_un.un_nla.nla_options))));
+		          EXTRACT_BE_32BITS(&lsap->lsa_un.un_nla.nla_options))));
 
 		ND_PRINT((ndo, "\n\t      Connected Routers:"));
 		ap = lsap->lsa_un.un_nla.nla_router;
@@ -574,9 +569,9 @@ ospf6_print_lsa(netdissect_options *ndo,
 		lsa_length -= sizeof (lsap->lsa_un.un_inter_ap.inter_ap_metric);
 		ND_TCHECK(lsap->lsa_un.un_inter_ap.inter_ap_metric);
 		ND_PRINT((ndo, ", metric %u",
-			EXTRACT_32BITS(&lsap->lsa_un.un_inter_ap.inter_ap_metric) & SLA_MASK_METRIC));
+			EXTRACT_BE_32BITS(&lsap->lsa_un.un_inter_ap.inter_ap_metric) & SLA_MASK_METRIC));
 
-		tptr = (uint8_t *)lsap->lsa_un.un_inter_ap.inter_ap_prefix;
+		tptr = (const uint8_t *)lsap->lsa_un.un_inter_ap.inter_ap_prefix;
 		while (lsa_length != 0) {
 			bytelen = ospf6_print_lsaprefix(ndo, tptr, lsa_length);
 			if (bytelen < 0)
@@ -591,15 +586,15 @@ ospf6_print_lsa(netdissect_options *ndo,
 			return (1);
 		lsa_length -= sizeof (lsap->lsa_un.un_asla.asla_metric);
 		ND_TCHECK(lsap->lsa_un.un_asla.asla_metric);
-		flags32 = EXTRACT_32BITS(&lsap->lsa_un.un_asla.asla_metric);
+		flags32 = EXTRACT_BE_32BITS(&lsap->lsa_un.un_asla.asla_metric);
 		ND_PRINT((ndo, "\n\t     Flags [%s]",
 		          bittok2str(ospf6_asla_flag_values, "none", flags32)));
 		ND_PRINT((ndo, " metric %u",
-		       EXTRACT_32BITS(&lsap->lsa_un.un_asla.asla_metric) &
+		       EXTRACT_BE_32BITS(&lsap->lsa_un.un_asla.asla_metric) &
 		       ASLA_MASK_METRIC));
 
-		tptr = (uint8_t *)lsap->lsa_un.un_asla.asla_prefix;
-		lsapp = (struct lsa6_prefix *)tptr;
+		tptr = (const uint8_t *)lsap->lsa_un.un_asla.asla_prefix;
+		lsapp = (const struct lsa6_prefix *)tptr;
 		bytelen = ospf6_print_lsaprefix(ndo, tptr, lsa_length);
 		if (bytelen < 0)
 			goto trunc;
@@ -607,9 +602,9 @@ ospf6_print_lsa(netdissect_options *ndo,
 		tptr += bytelen;
 
 		if ((flags32 & ASLA_FLAG_FWDADDR) != 0) {
-			struct in6_addr *fwdaddr6;
+			const struct in6_addr *fwdaddr6;
 
-			fwdaddr6 = (struct in6_addr *)tptr;
+			fwdaddr6 = (const struct in6_addr *)tptr;
 			if (lsa_length < sizeof (*fwdaddr6))
 				return (1);
 			lsa_length -= sizeof (*fwdaddr6);
@@ -623,9 +618,9 @@ ospf6_print_lsa(netdissect_options *ndo,
 			if (lsa_length < sizeof (uint32_t))
 				return (1);
 			lsa_length -= sizeof (uint32_t);
-			ND_TCHECK(*(uint32_t *)tptr);
+			ND_TCHECK(*(const uint32_t *)tptr);
 			ND_PRINT((ndo, " tag %s",
-			       ipaddr_string(ndo, (uint32_t *)tptr)));
+			       ipaddr_string(ndo, (const uint32_t *)tptr)));
 			tptr += sizeof(uint32_t);
 		}
 
@@ -633,9 +628,9 @@ ospf6_print_lsa(netdissect_options *ndo,
 			if (lsa_length < sizeof (uint32_t))
 				return (1);
 			lsa_length -= sizeof (uint32_t);
-			ND_TCHECK(*(uint32_t *)tptr);
+			ND_TCHECK(*(const uint32_t *)tptr);
 			ND_PRINT((ndo, " RefLSID: %s",
-			       ipaddr_string(ndo, (uint32_t *)tptr)));
+			       ipaddr_string(ndo, (const uint32_t *)tptr)));
 			tptr += sizeof(uint32_t);
 		}
 		break;
@@ -649,18 +644,19 @@ ospf6_print_lsa(netdissect_options *ndo,
 		ND_TCHECK(llsap->llsa_priandopt);
 		ND_PRINT((ndo, "\n\t      Options [%s]",
 		          bittok2str(ospf6_option_values, "none",
-		          EXTRACT_32BITS(&llsap->llsa_options))));
+		          EXTRACT_BE_32BITS(&llsap->llsa_options))));
 
 		if (lsa_length < sizeof (llsap->llsa_lladdr) + sizeof (llsap->llsa_nprefix))
 			return (1);
 		lsa_length -= sizeof (llsap->llsa_lladdr) + sizeof (llsap->llsa_nprefix);
-                prefixes = EXTRACT_32BITS(&llsap->llsa_nprefix);
+                ND_TCHECK(llsap->llsa_nprefix);
+                prefixes = EXTRACT_BE_32BITS(&llsap->llsa_nprefix);
 		ND_PRINT((ndo, "\n\t      Priority %d, Link-local address %s, Prefixes %d:",
                        llsap->llsa_priority,
                        ip6addr_string(ndo, &llsap->llsa_lladdr),
                        prefixes));
 
-		tptr = (uint8_t *)llsap->llsa_prefix;
+		tptr = (const uint8_t *)llsap->llsa_prefix;
 		while (prefixes > 0) {
 			bytelen = ospf6_print_lsaprefix(ndo, tptr, lsa_length);
 			if (bytelen < 0)
@@ -678,17 +674,17 @@ ospf6_print_lsa(netdissect_options *ndo,
 		lsa_length -= sizeof (lsap->lsa_un.un_intra_ap.intra_ap_rtid);
 		ND_TCHECK(lsap->lsa_un.un_intra_ap.intra_ap_rtid);
 		ospf6_print_ls_type(ndo,
-			EXTRACT_16BITS(&lsap->lsa_un.un_intra_ap.intra_ap_lstype),
+			EXTRACT_BE_16BITS(&lsap->lsa_un.un_intra_ap.intra_ap_lstype),
 			&lsap->lsa_un.un_intra_ap.intra_ap_lsid);
 
 		if (lsa_length < sizeof (lsap->lsa_un.un_intra_ap.intra_ap_nprefix))
 			return (1);
 		lsa_length -= sizeof (lsap->lsa_un.un_intra_ap.intra_ap_nprefix);
 		ND_TCHECK(lsap->lsa_un.un_intra_ap.intra_ap_nprefix);
-                prefixes = EXTRACT_16BITS(&lsap->lsa_un.un_intra_ap.intra_ap_nprefix);
+                prefixes = EXTRACT_BE_16BITS(&lsap->lsa_un.un_intra_ap.intra_ap_nprefix);
 		ND_PRINT((ndo, "\n\t      Prefixes %d:", prefixes));
 
-		tptr = (uint8_t *)lsap->lsa_un.un_intra_ap.intra_ap_prefix;
+		tptr = (const uint8_t *)lsap->lsa_un.un_intra_ap.intra_ap_prefix;
 		while (prefixes > 0) {
 			bytelen = ospf6_print_lsaprefix(ndo, tptr, lsa_length);
 			if (bytelen < 0)
@@ -738,68 +734,76 @@ ospf6_decode_v3(netdissect_options *ndo,
 
 	switch (op->ospf6_type) {
 
-	case OSPF_TYPE_HELLO:
+	case OSPF_TYPE_HELLO: {
+		register const struct hello6 *hellop = (const struct hello6 *)((const uint8_t *)op + OSPF6HDR_LEN);
+
+		ND_TCHECK_32BITS(&hellop->hello_options);
 		ND_PRINT((ndo, "\n\tOptions [%s]",
 		          bittok2str(ospf6_option_values, "none",
-		          EXTRACT_32BITS(&op->ospf6_hello.hello_options))));
+		          EXTRACT_BE_32BITS(&hellop->hello_options))));
 
-		ND_TCHECK(op->ospf6_hello.hello_deadint);
+		ND_TCHECK(hellop->hello_deadint);
 		ND_PRINT((ndo, "\n\t  Hello Timer %us, Dead Timer %us, Interface-ID %s, Priority %u",
-		          EXTRACT_16BITS(&op->ospf6_hello.hello_helloint),
-		          EXTRACT_16BITS(&op->ospf6_hello.hello_deadint),
-		          ipaddr_string(ndo, &op->ospf6_hello.hello_ifid),
-		          op->ospf6_hello.hello_priority));
+		          EXTRACT_BE_16BITS(&hellop->hello_helloint),
+		          EXTRACT_BE_16BITS(&hellop->hello_deadint),
+		          ipaddr_string(ndo, &hellop->hello_ifid),
+		          hellop->hello_priority));
 
-		ND_TCHECK(op->ospf6_hello.hello_dr);
-		if (EXTRACT_32BITS(&op->ospf6_hello.hello_dr) != 0)
+		ND_TCHECK(hellop->hello_dr);
+		if (EXTRACT_BE_32BITS(&hellop->hello_dr) != 0)
 			ND_PRINT((ndo, "\n\t  Designated Router %s",
-			    ipaddr_string(ndo, &op->ospf6_hello.hello_dr)));
-		ND_TCHECK(op->ospf6_hello.hello_bdr);
-		if (EXTRACT_32BITS(&op->ospf6_hello.hello_bdr) != 0)
+			    ipaddr_string(ndo, &hellop->hello_dr)));
+		ND_TCHECK(hellop->hello_bdr);
+		if (EXTRACT_BE_32BITS(&hellop->hello_bdr) != 0)
 			ND_PRINT((ndo, ", Backup Designated Router %s",
-			    ipaddr_string(ndo, &op->ospf6_hello.hello_bdr)));
+			    ipaddr_string(ndo, &hellop->hello_bdr)));
 		if (ndo->ndo_vflag > 1) {
 			ND_PRINT((ndo, "\n\t  Neighbor List:"));
-			ap = op->ospf6_hello.hello_neighbor;
-			while ((u_char *)ap < dataend) {
+			ap = hellop->hello_neighbor;
+			while ((const u_char *)ap < dataend) {
 				ND_TCHECK(*ap);
 				ND_PRINT((ndo, "\n\t    %s", ipaddr_string(ndo, ap)));
 				++ap;
 			}
 		}
 		break;	/* HELLO */
+	}
+
+	case OSPF_TYPE_DD: {
+		register const struct dd6 *ddp = (const struct dd6 *)((const uint8_t *)op + OSPF6HDR_LEN);
 
-	case OSPF_TYPE_DD:
-		ND_TCHECK(op->ospf6_db.db_options);
+		ND_TCHECK(ddp->db_options);
 		ND_PRINT((ndo, "\n\tOptions [%s]",
 		          bittok2str(ospf6_option_values, "none",
-		          EXTRACT_32BITS(&op->ospf6_db.db_options))));
-		ND_TCHECK(op->ospf6_db.db_flags);
+		          EXTRACT_BE_32BITS(&ddp->db_options))));
+		ND_TCHECK(ddp->db_flags);
 		ND_PRINT((ndo, ", DD Flags [%s]",
-		          bittok2str(ospf6_dd_flag_values,"none",op->ospf6_db.db_flags)));
+		          bittok2str(ospf6_dd_flag_values,"none",ddp->db_flags)));
 
-		ND_TCHECK(op->ospf6_db.db_seq);
+		ND_TCHECK(ddp->db_seq);
 		ND_PRINT((ndo, ", MTU %u, DD-Sequence 0x%08x",
-                       EXTRACT_16BITS(&op->ospf6_db.db_mtu),
-                       EXTRACT_32BITS(&op->ospf6_db.db_seq)));
+                       EXTRACT_BE_16BITS(&ddp->db_mtu),
+                       EXTRACT_BE_32BITS(&ddp->db_seq)));
 		if (ndo->ndo_vflag > 1) {
 			/* Print all the LS adv's */
-			lshp = op->ospf6_db.db_lshdr;
-			while ((u_char *)lshp < dataend) {
+			lshp = ddp->db_lshdr;
+			while ((const u_char *)lshp < dataend) {
 				if (ospf6_print_lshdr(ndo, lshp++, dataend))
 					goto trunc;
 			}
 		}
 		break;
+	}
 
 	case OSPF_TYPE_LS_REQ:
 		if (ndo->ndo_vflag > 1) {
-			lsrp = op->ospf6_lsr;
-			while ((u_char *)lsrp < dataend) {
+			lsrp = (const struct lsr6 *)((const uint8_t *)op + OSPF6HDR_LEN);
+			while ((const u_char *)lsrp < dataend) {
 				ND_TCHECK(*lsrp);
 				ND_PRINT((ndo, "\n\t  Advertising Router %s",
 				          ipaddr_string(ndo, &lsrp->ls_router)));
-				ospf6_print_ls_type(ndo, EXTRACT_16BITS(&lsrp->ls_type),
+				ospf6_print_ls_type(ndo,
+                                                    EXTRACT_BE_16BITS(&lsrp->ls_type),
                                                     &lsrp->ls_stateid);
 				++lsrp;
 			}
@@ -808,23 +812,24 @@ ospf6_decode_v3(netdissect_options *ndo,
 
 	case OSPF_TYPE_LS_UPDATE:
 		if (ndo->ndo_vflag > 1) {
-			lsap = op->ospf6_lsu.lsu_lsa;
-			ND_TCHECK(op->ospf6_lsu.lsu_count);
-			i = EXTRACT_32BITS(&op->ospf6_lsu.lsu_count);
-			while ((u_char *)lsap < dataend && i--) {
+			register const struct lsu6 *lsup = (const struct lsu6 *)((const uint8_t *)op + OSPF6HDR_LEN);
+
+			ND_TCHECK(lsup->lsu_count);
+			i = EXTRACT_BE_32BITS(&lsup->lsu_count);
+			lsap = lsup->lsu_lsa;
+			while ((const u_char *)lsap < dataend && i--) {
 				if (ospf6_print_lsa(ndo, lsap, dataend))
 					goto trunc;
-				lsap = (struct lsa6 *)((u_char *)lsap +
-				    EXTRACT_16BITS(&lsap->ls_hdr.ls_length));
+				lsap = (const struct lsa6 *)((const u_char *)lsap +
+				    EXTRACT_BE_16BITS(&lsap->ls_hdr.ls_length));
 			}
 		}
 		break;
 
-
 	case OSPF_TYPE_LS_ACK:
 		if (ndo->ndo_vflag > 1) {
-			lshp = op->ospf6_lsa.lsa_lshdr;
-			while ((u_char *)lshp < dataend) {
+			lshp = (const struct lsa6_hdr *)((const uint8_t *)op + OSPF6HDR_LEN);
+			while ((const u_char *)lshp < dataend) {
 				if (ospf6_print_lshdr(ndo, lshp++, dataend))
 					goto trunc;
 			}
@@ -852,11 +857,11 @@ ospf6_print_lls(netdissect_options *ndo,
 		goto trunc;
 	/* Checksum */
 	ND_TCHECK2(*cp, 2);
-	ND_PRINT((ndo, "\n\tLLS Checksum 0x%04x", EXTRACT_16BITS(cp)));
+	ND_PRINT((ndo, "\n\tLLS Checksum 0x%04x", EXTRACT_BE_16BITS(cp)));
 	cp += 2;
 	/* LLS Data Length */
 	ND_TCHECK2(*cp, 2);
-	llsdatalen = EXTRACT_16BITS(cp);
+	llsdatalen = EXTRACT_BE_16BITS(cp);
 	ND_PRINT((ndo, ", Data Length %u", llsdatalen));
 	if (llsdatalen < OSPF_LLS_HDRLEN || llsdatalen > len)
 		goto trunc;
@@ -883,11 +888,11 @@ ospf6_decode_at(netdissect_options *ndo,
 		goto trunc;
 	/* Authentication Type */
 	ND_TCHECK2(*cp, 2);
-	ND_PRINT((ndo, "\n\tAuthentication Type %s", tok2str(ospf6_auth_type_str, "unknown (0x%04x)", EXTRACT_16BITS(cp))));
+	ND_PRINT((ndo, "\n\tAuthentication Type %s", tok2str(ospf6_auth_type_str, "unknown (0x%04x)", EXTRACT_BE_16BITS(cp))));
 	cp += 2;
 	/* Auth Data Len */
 	ND_TCHECK2(*cp, 2);
-	authdatalen = EXTRACT_16BITS(cp);
+	authdatalen = EXTRACT_BE_16BITS(cp);
 	ND_PRINT((ndo, ", Length %u", authdatalen));
 	if (authdatalen < OSPF6_AT_HDRLEN || authdatalen > len)
 		goto trunc;
@@ -897,15 +902,15 @@ ospf6_decode_at(netdissect_options *ndo,
 	cp += 2;
 	/* Security Association ID */
 	ND_TCHECK2(*cp, 2);
-	ND_PRINT((ndo, ", SAID %u", EXTRACT_16BITS(cp)));
+	ND_PRINT((ndo, ", SAID %u", EXTRACT_BE_16BITS(cp)));
 	cp += 2;
 	/* Cryptographic Sequence Number (High-Order 32 Bits) */
 	ND_TCHECK2(*cp, 4);
-	ND_PRINT((ndo, ", CSN 0x%08x", EXTRACT_32BITS(cp)));
+	ND_PRINT((ndo, ", CSN 0x%08x", EXTRACT_BE_32BITS(cp)));
 	cp += 4;
 	/* Cryptographic Sequence Number (Low-Order 32 Bits) */
 	ND_TCHECK2(*cp, 4);
-	ND_PRINT((ndo, ":%08x", EXTRACT_32BITS(cp)));
+	ND_PRINT((ndo, ":%08x", EXTRACT_BE_32BITS(cp)));
 	cp += 4;
 	/* Authentication Data */
 	ND_TCHECK2(*cp, authdatalen - OSPF6_AT_HDRLEN);
@@ -927,11 +932,20 @@ ospf6_decode_v3_trailer(netdissect_options *ndo,
                         const struct ospf6hdr *op, const u_char *cp, const unsigned len)
 {
 	int llslen = 0;
-	u_char lls_hello = op->ospf6_type == OSPF_TYPE_HELLO &&
-	                   EXTRACT_32BITS(&op->ospf6_hello.hello_options) & OSPF6_OPTION_L;
-	u_char lls_dd    = op->ospf6_type == OSPF_TYPE_DD &&
-	                   EXTRACT_32BITS(&op->ospf6_db.db_options) & OSPF6_OPTION_L;
-
+	int lls_hello = 0;
+	int lls_dd = 0;
+
+	if (op->ospf6_type == OSPF_TYPE_HELLO) {
+		const struct hello6 *hellop = (const struct hello6 *)((const uint8_t *)op + OSPF6HDR_LEN);
+		ND_TCHECK(hellop->hello_options);
+		if (EXTRACT_BE_32BITS(&hellop->hello_options) & OSPF6_OPTION_L)
+			lls_hello = 1;
+	} else if (op->ospf6_type == OSPF_TYPE_DD) {
+		const struct dd6 *ddp = (const struct dd6 *)((const uint8_t *)op + OSPF6HDR_LEN);
+		ND_TCHECK(ddp->db_options);
+		if (EXTRACT_BE_32BITS(&ddp->db_options) & OSPF6_OPTION_L)
+			lls_dd = 1;
+	}
 	if ((lls_hello || lls_dd) && (llslen = ospf6_print_lls(ndo, cp, len)) < 0)
 		goto trunc;
 	return ospf6_decode_at(ndo, cp + llslen, len - llslen);
@@ -949,7 +963,7 @@ ospf6_print(netdissect_options *ndo,
 	register const char *cp;
 	uint16_t datalen;
 
-	op = (struct ospf6hdr *)bp;
+	op = (const struct ospf6hdr *)bp;
 
 	/* If the type is valid translate it, or just print the type */
 	/* value.  If it's not valid, say so and return */
@@ -966,7 +980,7 @@ ospf6_print(netdissect_options *ndo,
 
 	/* OSPFv3 data always comes first and optional trailing data may follow. */
 	ND_TCHECK(op->ospf6_len);
-	datalen = EXTRACT_16BITS(&op->ospf6_len);
+	datalen = EXTRACT_BE_16BITS(&op->ospf6_len);
 	if (datalen > length) {
 		ND_PRINT((ndo, " [len %d]", datalen));
 		return;
@@ -977,7 +991,7 @@ ospf6_print(netdissect_options *ndo,
 	ND_PRINT((ndo, "\n\tRouter-ID %s", ipaddr_string(ndo, &op->ospf6_routerid)));
 
 	ND_TCHECK(op->ospf6_areaid);
-	if (EXTRACT_32BITS(&op->ospf6_areaid) != 0)
+	if (EXTRACT_BE_32BITS(&op->ospf6_areaid) != 0)
 		ND_PRINT((ndo, ", Area %s", ipaddr_string(ndo, &op->ospf6_areaid)));
 	else
 		ND_PRINT((ndo, ", Backbone Area"));