]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-decnet.c
Add program_name field in the netdissect_options structure
[tcpdump] / print-decnet.c
index da5a0ca17e1926b60f9663fa947b489b7bf24207..41d022fc42b2bc267ccc026d45b1a78cd8d246ed 100644 (file)
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  */
 
-#ifndef lint
-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-decnet.c,v 1.36 2002-09-05 21:25:39 guy Exp $ (LBL)";
-#endif
-
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
@@ -41,22 +36,462 @@ struct rtentry;
 #include <stdlib.h>
 #include <string.h>
 
-#include "decnet.h"
 #include "extract.h"
-#include "interface.h"
+#include "netdissect.h"
 #include "addrtoname.h"
 
+static const char tstr[] = "[|decnet]";
+
+#ifndef _WIN32
+typedef uint8_t byte[1];               /* single byte field */
+#else
+/*
+ * the keyword 'byte' generates conflicts in Windows
+ */
+typedef unsigned char Byte[1];         /* single byte field */
+#define byte Byte
+#endif /* _WIN32 */
+typedef uint8_t word[2];               /* 2 byte field */
+typedef uint8_t longword[4];           /* 4 bytes field */
+
+/*
+ * Definitions for DECNET Phase IV protocol headers
+ */
+union etheraddress {
+       uint8_t   dne_addr[6];          /* full ethernet address */
+       struct {
+               uint8_t dne_hiord[4];   /* DECnet HIORD prefix */
+               uint8_t dne_nodeaddr[2]; /* DECnet node address */
+       } dne_remote;
+};
+
+typedef union etheraddress etheraddr;  /* Ethernet address */
+
+#define HIORD 0x000400aa               /* high 32-bits of address (swapped) */
+
+#define AREAMASK       0176000         /* mask for area field */
+#define        AREASHIFT       10              /* bit-offset for area field */
+#define NODEMASK       01777           /* mask for node address field */
+
+#define DN_MAXADDL     20              /* max size of DECnet address */
+struct dn_naddr {
+       uint16_t        a_len;          /* length of address */
+       uint8_t a_addr[DN_MAXADDL]; /* address as bytes */
+};
+
+/*
+ * Define long and short header formats.
+ */
+struct shorthdr
+  {
+    byte       sh_flags;               /* route flags */
+    word       sh_dst;                 /* destination node address */
+    word       sh_src;                 /* source node address */
+    byte       sh_visits;              /* visit count */
+  };
+
+struct longhdr
+  {
+    byte       lg_flags;               /* route flags */
+    byte       lg_darea;               /* destination area (reserved) */
+    byte       lg_dsarea;              /* destination subarea (reserved) */
+    etheraddr  lg_dst;                 /* destination id */
+    byte       lg_sarea;               /* source area (reserved) */
+    byte       lg_ssarea;              /* source subarea (reserved) */
+    etheraddr  lg_src;                 /* source id */
+    byte       lg_nextl2;              /* next level 2 router (reserved) */
+    byte       lg_visits;              /* visit count */
+    byte       lg_service;             /* service class (reserved) */
+    byte       lg_pt;                  /* protocol type (reserved) */
+  };
+
+union routehdr
+  {
+    struct shorthdr rh_short;          /* short route header */
+    struct longhdr rh_long;            /* long route header */
+  };
+
+/*
+ * Define the values of various fields in the protocol messages.
+ *
+ * 1. Data packet formats.
+ */
+#define RMF_MASK       7               /* mask for message type */
+#define RMF_SHORT      2               /* short message format */
+#define RMF_LONG       6               /* long message format */
+#ifndef RMF_RQR
+#define RMF_RQR                010             /* request return to sender */
+#define RMF_RTS                020             /* returning to sender */
+#define RMF_IE         040             /* intra-ethernet packet */
+#endif /* RMR_RQR */
+#define RMF_FVER       0100            /* future version flag */
+#define RMF_PAD                0200            /* pad field */
+#define RMF_PADMASK    0177            /* pad field mask */
+
+#define VIS_MASK       077             /* visit field mask */
+
+/*
+ * 2. Control packet formats.
+ */
+#define RMF_CTLMASK    017             /* mask for message type */
+#define RMF_CTLMSG     01              /* control message indicator */
+#define RMF_INIT       01              /* initialization message */
+#define RMF_VER                03              /* verification message */
+#define RMF_TEST       05              /* hello and test message */
+#define RMF_L1ROUT     07              /* level 1 routing message */
+#define RMF_L2ROUT     011             /* level 2 routing message */
+#define RMF_RHELLO     013             /* router hello message */
+#define RMF_EHELLO     015             /* endnode hello message */
+
+#define TI_L2ROUT      01              /* level 2 router */
+#define TI_L1ROUT      02              /* level 1 router */
+#define TI_ENDNODE     03              /* endnode */
+#define TI_VERIF       04              /* verification required */
+#define TI_BLOCK       010             /* blocking requested */
+
+#define VE_VERS                2               /* version number (2) */
+#define VE_ECO         0               /* ECO number */
+#define VE_UECO                0               /* user ECO number (0) */
+
+#define P3_VERS                1               /* phase III version number (1) */
+#define P3_ECO         3               /* ECO number (3) */
+#define P3_UECO                0               /* user ECO number (0) */
+
+#define II_L2ROUT      01              /* level 2 router */
+#define II_L1ROUT      02              /* level 1 router */
+#define II_ENDNODE     03              /* endnode */
+#define II_VERIF       04              /* verification required */
+#define II_NOMCAST     040             /* no multicast traffic accepted */
+#define II_BLOCK       0100            /* blocking requested */
+#define II_TYPEMASK    03              /* mask for node type */
+
+#define TESTDATA       0252            /* test data bytes */
+#define TESTLEN                1               /* length of transmitted test data */
+
+/*
+ * Define control message formats.
+ */
+struct initmsgIII                      /* phase III initialization message */
+  {
+    byte       inIII_flags;            /* route flags */
+    word       inIII_src;              /* source node address */
+    byte       inIII_info;             /* routing layer information */
+    word       inIII_blksize;          /* maximum data link block size */
+    byte       inIII_vers;             /* version number */
+    byte       inIII_eco;              /* ECO number */
+    byte       inIII_ueco;             /* user ECO number */
+    byte       inIII_rsvd;             /* reserved image field */
+  };
+
+struct initmsg                         /* initialization message */
+  {
+    byte       in_flags;               /* route flags */
+    word       in_src;                 /* source node address */
+    byte       in_info;                /* routing layer information */
+    word       in_blksize;             /* maximum data link block size */
+    byte       in_vers;                /* version number */
+    byte       in_eco;                 /* ECO number */
+    byte       in_ueco;                /* user ECO number */
+    word       in_hello;               /* hello timer */
+    byte       in_rsvd;                /* reserved image field */
+  };
+
+struct verifmsg                                /* verification message */
+  {
+    byte       ve_flags;               /* route flags */
+    word       ve_src;                 /* source node address */
+    byte       ve_fcnval;              /* function value image field */
+  };
+
+struct testmsg                         /* hello and test message */
+  {
+    byte       te_flags;               /* route flags */
+    word       te_src;                 /* source node address */
+    byte       te_data;                /* test data image field */
+  };
+
+struct l1rout                          /* level 1 routing message */
+  {
+    byte       r1_flags;               /* route flags */
+    word       r1_src;                 /* source node address */
+    byte       r1_rsvd;                /* reserved field */
+  };
+
+struct l2rout                          /* level 2 routing message */
+  {
+    byte       r2_flags;               /* route flags */
+    word       r2_src;                 /* source node address */
+    byte       r2_rsvd;                /* reserved field */
+  };
+
+struct rhellomsg                       /* router hello message */
+  {
+    byte       rh_flags;               /* route flags */
+    byte       rh_vers;                /* version number */
+    byte       rh_eco;                 /* ECO number */
+    byte       rh_ueco;                /* user ECO number */
+    etheraddr  rh_src;                 /* source id */
+    byte       rh_info;                /* routing layer information */
+    word       rh_blksize;             /* maximum data link block size */
+    byte       rh_priority;            /* router's priority */
+    byte       rh_area;                /* reserved */
+    word       rh_hello;               /* hello timer */
+    byte       rh_mpd;                 /* reserved */
+  };
+
+struct ehellomsg                       /* endnode hello message */
+  {
+    byte       eh_flags;               /* route flags */
+    byte       eh_vers;                /* version number */
+    byte       eh_eco;                 /* ECO number */
+    byte       eh_ueco;                /* user ECO number */
+    etheraddr  eh_src;                 /* source id */
+    byte       eh_info;                /* routing layer information */
+    word       eh_blksize;             /* maximum data link block size */
+    byte       eh_area;                /* area (reserved) */
+    byte       eh_seed[8];             /* verification seed */
+    etheraddr  eh_router;              /* designated router */
+    word       eh_hello;               /* hello timer */
+    byte       eh_mpd;                 /* (reserved) */
+    byte       eh_data;                /* test data image field */
+  };
+
+union controlmsg
+  {
+    struct initmsg     cm_init;        /* initialization message */
+    struct verifmsg    cm_ver;         /* verification message */
+    struct testmsg     cm_test;        /* hello and test message */
+    struct l1rout      cm_l1rou;       /* level 1 routing message */
+    struct l2rout      cm_l2rout;      /* level 2 routing message */
+    struct rhellomsg   cm_rhello;      /* router hello message */
+    struct ehellomsg   cm_ehello;      /* endnode hello message */
+  };
+
+/* Macros for decoding routing-info fields */
+#define        RI_COST(x)      ((x)&0777)
+#define        RI_HOPS(x)      (((x)>>10)&037)
+
+/*
+ * NSP protocol fields and values.
+ */
+
+#define NSP_TYPEMASK 014               /* mask to isolate type code */
+#define NSP_SUBMASK 0160               /* mask to isolate subtype code */
+#define NSP_SUBSHFT 4                  /* shift to move subtype code */
+
+#define MFT_DATA 0                     /* data message */
+#define MFT_ACK  04                    /* acknowledgement message */
+#define MFT_CTL  010                   /* control message */
+
+#define MFS_ILS  020                   /* data or I/LS indicator */
+#define MFS_BOM  040                   /* beginning of message (data) */
+#define MFS_MOM  0                     /* middle of message (data) */
+#define MFS_EOM  0100                  /* end of message (data) */
+#define MFS_INT  040                   /* interrupt message */
+
+#define MFS_DACK 0                     /* data acknowledgement */
+#define MFS_IACK 020                   /* I/LS acknowledgement */
+#define MFS_CACK 040                   /* connect acknowledgement */
+
+#define MFS_NOP  0                     /* no operation */
+#define MFS_CI   020                   /* connect initiate */
+#define MFS_CC   040                   /* connect confirm */
+#define MFS_DI   060                   /* disconnect initiate */
+#define MFS_DC   0100                  /* disconnect confirm */
+#define MFS_RCI  0140                  /* retransmitted connect initiate */
+
+#define SGQ_ACK  0100000               /* ack */
+#define SGQ_NAK  0110000               /* negative ack */
+#define SGQ_OACK 0120000               /* other channel ack */
+#define SGQ_ONAK 0130000               /* other channel negative ack */
+#define SGQ_MASK 07777                 /* mask to isolate seq # */
+#define SGQ_OTHER 020000               /* other channel qualifier */
+#define SGQ_DELAY 010000               /* ack delay flag */
+
+#define SGQ_EOM  0100000               /* pseudo flag for end-of-message */
+
+#define LSM_MASK 03                    /* mask for modifier field */
+#define LSM_NOCHANGE 0                 /* no change */
+#define LSM_DONOTSEND 1                        /* do not send data */
+#define LSM_SEND 2                     /* send data */
+
+#define LSI_MASK 014                   /* mask for interpretation field */
+#define LSI_DATA 0                     /* data segment or message count */
+#define LSI_INTR 4                     /* interrupt request count */
+#define LSI_INTM 0377                  /* funny marker for int. message */
+
+#define COS_MASK 014                   /* mask for flow control field */
+#define COS_NONE 0                     /* no flow control */
+#define COS_SEGMENT 04                 /* segment flow control */
+#define COS_MESSAGE 010                        /* message flow control */
+#define COS_CRYPTSER 020               /* cryptographic services requested */
+#define COS_DEFAULT 1                  /* default value for field */
+
+#define COI_MASK 3                     /* mask for version field */
+#define COI_32 0                       /* version 3.2 */
+#define COI_31 1                       /* version 3.1 */
+#define COI_40 2                       /* version 4.0 */
+#define COI_41 3                       /* version 4.1 */
+
+#define MNU_MASK 140                   /* mask for session control version */
+#define MNU_10 000                             /* session V1.0 */
+#define MNU_20 040                             /* session V2.0 */
+#define MNU_ACCESS 1                   /* access control present */
+#define MNU_USRDATA 2                  /* user data field present */
+#define MNU_INVKPROXY 4                        /* invoke proxy field present */
+#define MNU_UICPROXY 8                 /* use uic-based proxy */
+
+#define DC_NORESOURCES 1               /* no resource reason code */
+#define DC_NOLINK 41                   /* no link terminate reason code */
+#define DC_COMPLETE 42                 /* disconnect complete reason code */
+
+#define DI_NOERROR 0                   /* user disconnect */
+#define DI_SHUT 3                      /* node is shutting down */
+#define DI_NOUSER 4                    /* destination end user does not exist */
+#define DI_INVDEST 5                   /* invalid end user destination */
+#define DI_REMRESRC 6                  /* insufficient remote resources */
+#define DI_TPA 8                       /* third party abort */
+#define DI_PROTOCOL 7                  /* protocol error discovered */
+#define DI_ABORT 9                     /* user abort */
+#define DI_LOCALRESRC 32               /* insufficient local resources */
+#define DI_REMUSERRESRC 33             /* insufficient remote user resources */
+#define DI_BADACCESS 34                        /* bad access control information */
+#define DI_BADACCNT 36                 /* bad ACCOUNT information */
+#define DI_CONNECTABORT 38             /* connect request cancelled */
+#define DI_TIMEDOUT 38                 /* remote node or user crashed */
+#define DI_UNREACHABLE 39              /* local timers expired due to ... */
+#define DI_BADIMAGE 43                 /* bad image data in connect */
+#define DI_SERVMISMATCH 54             /* cryptographic service mismatch */
+
+#define UC_OBJREJECT 0                 /* object rejected connect */
+#define UC_USERDISCONNECT 0            /* user disconnect */
+#define UC_RESOURCES 1                 /* insufficient resources (local or remote) */
+#define UC_NOSUCHNODE 2                        /* unrecognized node name */
+#define UC_REMOTESHUT 3                        /* remote node shutting down */
+#define UC_NOSUCHOBJ 4                 /* unrecognized object */
+#define UC_INVOBJFORMAT 5              /* invalid object name format */
+#define UC_OBJTOOBUSY 6                        /* object too busy */
+#define UC_NETWORKABORT 8              /* network abort */
+#define UC_USERABORT 9                 /* user abort */
+#define UC_INVNODEFORMAT 10            /* invalid node name format */
+#define UC_LOCALSHUT 11                        /* local node shutting down */
+#define UC_ACCESSREJECT 34             /* invalid access control information */
+#define UC_NORESPONSE 38               /* no response from object */
+#define UC_UNREACHABLE 39              /* node unreachable */
+
+/*
+ * NSP message formats.
+ */
+struct nsphdr                          /* general nsp header */
+  {
+    byte       nh_flags;               /* message flags */
+    word       nh_dst;                 /* destination link address */
+    word       nh_src;                 /* source link address */
+  };
+
+struct seghdr                          /* data segment header */
+  {
+    byte       sh_flags;               /* message flags */
+    word       sh_dst;                 /* destination link address */
+    word       sh_src;                 /* source link address */
+    word       sh_seq[3];              /* sequence numbers */
+  };
+
+struct minseghdr                       /* minimum data segment header */
+  {
+    byte       ms_flags;               /* message flags */
+    word       ms_dst;                 /* destination link address */
+    word       ms_src;                 /* source link address */
+    word       ms_seq;                 /* sequence number */
+  };
+
+struct lsmsg                           /* link service message (after hdr) */
+  {
+    byte       ls_lsflags;             /* link service flags */
+    byte       ls_fcval;               /* flow control value */
+  };
+
+struct ackmsg                          /* acknowledgement message */
+  {
+    byte       ak_flags;               /* message flags */
+    word       ak_dst;                 /* destination link address */
+    word       ak_src;                 /* source link address */
+    word       ak_acknum[2];           /* acknowledgement numbers */
+  };
+
+struct minackmsg                       /* minimum acknowledgement message */
+  {
+    byte       mk_flags;               /* message flags */
+    word       mk_dst;                 /* destination link address */
+    word       mk_src;                 /* source link address */
+    word       mk_acknum;              /* acknowledgement number */
+  };
+
+struct ciackmsg                                /* connect acknowledgement message */
+  {
+    byte       ck_flags;               /* message flags */
+    word       ck_dst;                 /* destination link address */
+  };
+
+struct cimsg                           /* connect initiate message */
+  {
+    byte       ci_flags;               /* message flags */
+    word       ci_dst;                 /* destination link address (0) */
+    word       ci_src;                 /* source link address */
+    byte       ci_services;            /* requested services */
+    byte       ci_info;                /* information */
+    word       ci_segsize;             /* maximum segment size */
+  };
+
+struct ccmsg                           /* connect confirm message */
+  {
+    byte       cc_flags;               /* message flags */
+    word       cc_dst;                 /* destination link address */
+    word       cc_src;                 /* source link address */
+    byte       cc_services;            /* requested services */
+    byte       cc_info;                /* information */
+    word       cc_segsize;             /* maximum segment size */
+    byte       cc_optlen;              /* optional data length */
+  };
+
+struct cnmsg                           /* generic connect message */
+  {
+    byte       cn_flags;               /* message flags */
+    word       cn_dst;                 /* destination link address */
+    word       cn_src;                 /* source link address */
+    byte       cn_services;            /* requested services */
+    byte       cn_info;                /* information */
+    word       cn_segsize;             /* maximum segment size */
+  };
+
+struct dimsg                           /* disconnect initiate message */
+  {
+    byte       di_flags;               /* message flags */
+    word       di_dst;                 /* destination link address */
+    word       di_src;                 /* source link address */
+    word       di_reason;              /* reason code */
+    byte       di_optlen;              /* optional data length */
+  };
+
+struct dcmsg                           /* disconnect confirm message */
+  {
+    byte       dc_flags;               /* message flags */
+    word       dc_dst;                 /* destination link address */
+    word       dc_src;                 /* source link address */
+    word       dc_reason;              /* reason code */
+  };
+
 /* Forwards */
-static void print_decnet_ctlmsg(const union routehdr *, u_int);
-static void print_t_info(int);
-static void print_l1_routes(const char *, u_int);
-static void print_l2_routes(const char *, u_int);
-static void print_i_info(int);
-static void print_elist(const char *, u_int);
-static void print_nsp(const u_char *, u_int);
-static void print_reason(int);
+static int print_decnet_ctlmsg(netdissect_options *, const union routehdr *, u_int, u_int);
+static void print_t_info(netdissect_options *, int);
+static int print_l1_routes(netdissect_options *, const char *, u_int);
+static int print_l2_routes(netdissect_options *, const char *, u_int);
+static void print_i_info(netdissect_options *, int);
+static int print_elist(const char *, u_int);
+static int print_nsp(netdissect_options *, const u_char *, u_int);
+static void print_reason(netdissect_options *, int);
 #ifdef PRINT_NSPDATA
-static void pdata(u_char *, int);
+static void pdata(netdissect_options *, u_char *, u_int);
 #endif
 
 #ifndef HAVE_NETDNET_DNETDB_H_DNET_HTOA
@@ -64,108 +499,136 @@ extern char *dnet_htoa(struct dn_naddr *);
 #endif
 
 void
-decnet_print(register const u_char *ap, register u_int length,
-            register u_int caplen)
+decnet_print(netdissect_options *ndo,
+             register const u_char *ap, register u_int length,
+             register u_int caplen)
 {
-       static union routehdr rhcopy;
-       register union routehdr *rhp = &rhcopy;
+       register const union routehdr *rhp;
        register int mflags;
        int dst, src, hops;
-       u_int rhlen, nsplen, pktlen;
+       u_int nsplen, pktlen;
        const u_char *nspp;
 
        if (length < sizeof(struct shorthdr)) {
-               (void)printf("[|decnet]");
+               ND_PRINT((ndo, "%s", tstr));
                return;
        }
 
+       ND_TCHECK2(*ap, sizeof(short));
        pktlen = EXTRACT_LE_16BITS(ap);
+       if (pktlen < sizeof(struct shorthdr)) {
+               ND_PRINT((ndo, "%s", tstr));
+               return;
+       }
+       if (pktlen > length) {
+               ND_PRINT((ndo, "%s", tstr));
+               return;
+       }
+       length = pktlen;
 
-       rhlen = min(length, caplen);
-       rhlen = min(rhlen, sizeof(*rhp));
-       memcpy((char *)rhp, (char *)&(ap[sizeof(short)]), rhlen);
-
+       rhp = (const union routehdr *)&(ap[sizeof(short)]);
+       ND_TCHECK(rhp->rh_short.sh_flags);
        mflags = EXTRACT_LE_8BITS(rhp->rh_short.sh_flags);
 
        if (mflags & RMF_PAD) {
            /* pad bytes of some sort in front of message */
            u_int padlen = mflags & RMF_PADMASK;
-           if (vflag)
-               (void) printf("[pad:%d] ", padlen);
+           if (ndo->ndo_vflag)
+               ND_PRINT((ndo, "[pad:%d] ", padlen));
+           if (length < padlen + 2) {
+               ND_PRINT((ndo, "%s", tstr));
+               return;
+           }
+           ND_TCHECK2(ap[sizeof(short)], padlen);
            ap += padlen;
            length -= padlen;
            caplen -= padlen;
-           rhlen = min(length, caplen);
-           rhlen = min(rhlen, sizeof(*rhp));
-           memcpy((char *)rhp, (char *)&(ap[sizeof(short)]), rhlen);
+           rhp = (const union routehdr *)&(ap[sizeof(short)]);
            mflags = EXTRACT_LE_8BITS(rhp->rh_short.sh_flags);
        }
 
        if (mflags & RMF_FVER) {
-               (void) printf("future-version-decnet");
-               default_print(ap, length);
+               ND_PRINT((ndo, "future-version-decnet"));
+               ND_DEFAULTPRINT(ap, min(length, caplen));
                return;
        }
 
        /* is it a control message? */
        if (mflags & RMF_CTLMSG) {
-               print_decnet_ctlmsg(rhp, min(length, caplen));
+               if (!print_decnet_ctlmsg(ndo, rhp, length, caplen))
+                       goto trunc;
                return;
        }
 
        switch (mflags & RMF_MASK) {
        case RMF_LONG:
+           if (length < sizeof(struct longhdr)) {
+               ND_PRINT((ndo, "%s", tstr));
+               return;
+           }
+           ND_TCHECK(rhp->rh_long);
            dst =
                EXTRACT_LE_16BITS(rhp->rh_long.lg_dst.dne_remote.dne_nodeaddr);
            src =
                EXTRACT_LE_16BITS(rhp->rh_long.lg_src.dne_remote.dne_nodeaddr);
            hops = EXTRACT_LE_8BITS(rhp->rh_long.lg_visits);
            nspp = &(ap[sizeof(short) + sizeof(struct longhdr)]);
-           nsplen = min((length - sizeof(struct longhdr)),
-                        (caplen - sizeof(struct longhdr)));
+           nsplen = length - sizeof(struct longhdr);
            break;
        case RMF_SHORT:
+           ND_TCHECK(rhp->rh_short);
            dst = EXTRACT_LE_16BITS(rhp->rh_short.sh_dst);
            src = EXTRACT_LE_16BITS(rhp->rh_short.sh_src);
            hops = (EXTRACT_LE_8BITS(rhp->rh_short.sh_visits) & VIS_MASK)+1;
            nspp = &(ap[sizeof(short) + sizeof(struct shorthdr)]);
-           nsplen = min((length - sizeof(struct shorthdr)),
-                        (caplen - sizeof(struct shorthdr)));
+           nsplen = length - sizeof(struct shorthdr);
            break;
        default:
-           (void) printf("unknown message flags under mask");
-           default_print((u_char *)ap, length);
+           ND_PRINT((ndo, "unknown message flags under mask"));
+           ND_DEFAULTPRINT((const u_char *)ap, min(length, caplen));
            return;
        }
 
-       (void)printf("%s > %s %d ",
-                       dnaddr_string(src), dnaddr_string(dst), pktlen);
-       if (vflag) {
+       ND_PRINT((ndo, "%s > %s %d ",
+                       dnaddr_string(ndo, src), dnaddr_string(ndo, dst), pktlen));
+       if (ndo->ndo_vflag) {
            if (mflags & RMF_RQR)
-               (void)printf("RQR ");
+               ND_PRINT((ndo, "RQR "));
            if (mflags & RMF_RTS)
-               (void)printf("RTS ");
+               ND_PRINT((ndo, "RTS "));
            if (mflags & RMF_IE)
-               (void)printf("IE ");
-           (void)printf("%d hops ", hops);
+               ND_PRINT((ndo, "IE "));
+           ND_PRINT((ndo, "%d hops ", hops));
        }
 
-       print_nsp(nspp, nsplen);
+       if (!print_nsp(ndo, nspp, nsplen))
+               goto trunc;
+       return;
+
+trunc:
+       ND_PRINT((ndo, "%s", tstr));
+       return;
 }
 
-static void
-print_decnet_ctlmsg(register const union routehdr *rhp, u_int length)
+static int
+print_decnet_ctlmsg(netdissect_options *ndo,
+                    register const union routehdr *rhp, u_int length,
+                    u_int caplen)
 {
        int mflags = EXTRACT_LE_8BITS(rhp->rh_short.sh_flags);
-       register union controlmsg *cmp = (union controlmsg *)rhp;
+       register const union controlmsg *cmp = (const union controlmsg *)rhp;
        int src, dst, info, blksize, eco, ueco, hello, other, vers;
        etheraddr srcea, rtea;
        int priority;
-       char *rhpx = (char *)rhp;
+       const char *rhpx = (const char *)rhp;
+       int ret;
 
        switch (mflags & RMF_CTLMASK) {
        case RMF_INIT:
-           (void)printf("init ");
+           ND_PRINT((ndo, "init "));
+           if (length < sizeof(struct initmsg))
+               goto trunc;
+           ND_TCHECK(cmp->cm_init);
            src = EXTRACT_LE_16BITS(cmp->cm_init.in_src);
            info = EXTRACT_LE_8BITS(cmp->cm_init.in_info);
            blksize = EXTRACT_LE_16BITS(cmp->cm_init.in_blksize);
@@ -173,106 +636,135 @@ print_decnet_ctlmsg(register const union routehdr *rhp, u_int length)
            eco = EXTRACT_LE_8BITS(cmp->cm_init.in_eco);
            ueco = EXTRACT_LE_8BITS(cmp->cm_init.in_ueco);
            hello = EXTRACT_LE_16BITS(cmp->cm_init.in_hello);
-           print_t_info(info);
-           (void)printf(
+           print_t_info(ndo, info);
+           ND_PRINT((ndo,
                "src %sblksize %d vers %d eco %d ueco %d hello %d",
-                       dnaddr_string(src), blksize, vers, eco, ueco,
-                       hello);
+                       dnaddr_string(ndo, src), blksize, vers, eco, ueco,
+                       hello));
+           ret = 1;
            break;
        case RMF_VER:
-           (void)printf("verification ");
+           ND_PRINT((ndo, "verification "));
+           if (length < sizeof(struct verifmsg))
+               goto trunc;
+           ND_TCHECK(cmp->cm_ver);
            src = EXTRACT_LE_16BITS(cmp->cm_ver.ve_src);
            other = EXTRACT_LE_8BITS(cmp->cm_ver.ve_fcnval);
-           (void)printf("src %s fcnval %o", dnaddr_string(src), other);
+           ND_PRINT((ndo, "src %s fcnval %o", dnaddr_string(ndo, src), other));
+           ret = 1;
            break;
        case RMF_TEST:
-           (void)printf("test ");
+           ND_PRINT((ndo, "test "));
+           if (length < sizeof(struct testmsg))
+               goto trunc;
+           ND_TCHECK(cmp->cm_test);
            src = EXTRACT_LE_16BITS(cmp->cm_test.te_src);
            other = EXTRACT_LE_8BITS(cmp->cm_test.te_data);
-           (void)printf("src %s data %o", dnaddr_string(src), other);
+           ND_PRINT((ndo, "src %s data %o", dnaddr_string(ndo, src), other));
+           ret = 1;
            break;
        case RMF_L1ROUT:
-           (void)printf("lev-1-routing ");
+           ND_PRINT((ndo, "lev-1-routing "));
+           if (length < sizeof(struct l1rout))
+               goto trunc;
+           ND_TCHECK(cmp->cm_l1rou);
            src = EXTRACT_LE_16BITS(cmp->cm_l1rou.r1_src);
-           (void)printf("src %s ", dnaddr_string(src));
-           print_l1_routes(&(rhpx[sizeof(struct l1rout)]),
+           ND_PRINT((ndo, "src %s ", dnaddr_string(ndo, src)));
+           ret = print_l1_routes(ndo, &(rhpx[sizeof(struct l1rout)]),
                                length - sizeof(struct l1rout));
            break;
        case RMF_L2ROUT:
-           (void)printf("lev-2-routing ");
+           ND_PRINT((ndo, "lev-2-routing "));
+           if (length < sizeof(struct l2rout))
+               goto trunc;
+           ND_TCHECK(cmp->cm_l2rout);
            src = EXTRACT_LE_16BITS(cmp->cm_l2rout.r2_src);
-           (void)printf("src %s ", dnaddr_string(src));
-           print_l2_routes(&(rhpx[sizeof(struct l2rout)]),
+           ND_PRINT((ndo, "src %s ", dnaddr_string(ndo, src)));
+           ret = print_l2_routes(ndo, &(rhpx[sizeof(struct l2rout)]),
                                length - sizeof(struct l2rout));
            break;
        case RMF_RHELLO:
-           (void)printf("router-hello ");
+           ND_PRINT((ndo, "router-hello "));
+           if (length < sizeof(struct rhellomsg))
+               goto trunc;
+           ND_TCHECK(cmp->cm_rhello);
            vers = EXTRACT_LE_8BITS(cmp->cm_rhello.rh_vers);
            eco = EXTRACT_LE_8BITS(cmp->cm_rhello.rh_eco);
            ueco = EXTRACT_LE_8BITS(cmp->cm_rhello.rh_ueco);
-           memcpy((char *)&srcea, (char *)&(cmp->cm_rhello.rh_src),
+           memcpy((char *)&srcea, (const char *)&(cmp->cm_rhello.rh_src),
                sizeof(srcea));
            src = EXTRACT_LE_16BITS(srcea.dne_remote.dne_nodeaddr);
            info = EXTRACT_LE_8BITS(cmp->cm_rhello.rh_info);
            blksize = EXTRACT_LE_16BITS(cmp->cm_rhello.rh_blksize);
            priority = EXTRACT_LE_8BITS(cmp->cm_rhello.rh_priority);
            hello = EXTRACT_LE_16BITS(cmp->cm_rhello.rh_hello);
-           print_i_info(info);
-           (void)printf(
+           print_i_info(ndo, info);
+           ND_PRINT((ndo,
            "vers %d eco %d ueco %d src %s blksize %d pri %d hello %d",
-                       vers, eco, ueco, dnaddr_string(src),
-                       blksize, priority, hello);
-           print_elist(&(rhpx[sizeof(struct rhellomsg)]),
+                       vers, eco, ueco, dnaddr_string(ndo, src),
+                       blksize, priority, hello));
+           ret = print_elist(&(rhpx[sizeof(struct rhellomsg)]),
                                length - sizeof(struct rhellomsg));
            break;
        case RMF_EHELLO:
-           (void)printf("endnode-hello ");
+           ND_PRINT((ndo, "endnode-hello "));
+           if (length < sizeof(struct ehellomsg))
+               goto trunc;
+           ND_TCHECK(cmp->cm_ehello);
            vers = EXTRACT_LE_8BITS(cmp->cm_ehello.eh_vers);
            eco = EXTRACT_LE_8BITS(cmp->cm_ehello.eh_eco);
            ueco = EXTRACT_LE_8BITS(cmp->cm_ehello.eh_ueco);
-           memcpy((char *)&srcea, (char *)&(cmp->cm_ehello.eh_src),
+           memcpy((char *)&srcea, (const char *)&(cmp->cm_ehello.eh_src),
                sizeof(srcea));
            src = EXTRACT_LE_16BITS(srcea.dne_remote.dne_nodeaddr);
            info = EXTRACT_LE_8BITS(cmp->cm_ehello.eh_info);
            blksize = EXTRACT_LE_16BITS(cmp->cm_ehello.eh_blksize);
            /*seed*/
-           memcpy((char *)&rtea, (char *)&(cmp->cm_ehello.eh_router),
+           memcpy((char *)&rtea, (const char *)&(cmp->cm_ehello.eh_router),
                sizeof(rtea));
            dst = EXTRACT_LE_16BITS(rtea.dne_remote.dne_nodeaddr);
            hello = EXTRACT_LE_16BITS(cmp->cm_ehello.eh_hello);
            other = EXTRACT_LE_8BITS(cmp->cm_ehello.eh_data);
-           print_i_info(info);
-           (void)printf(
+           print_i_info(ndo, info);
+           ND_PRINT((ndo,
        "vers %d eco %d ueco %d src %s blksize %d rtr %s hello %d data %o",
-                       vers, eco, ueco, dnaddr_string(src),
-                       blksize, dnaddr_string(dst), hello, other);
+                       vers, eco, ueco, dnaddr_string(ndo, src),
+                       blksize, dnaddr_string(ndo, dst), hello, other));
+           ret = 1;
            break;
 
        default:
-           (void)printf("unknown control message");
-           default_print((u_char *)rhp, length);
+           ND_PRINT((ndo, "unknown control message"));
+           ND_DEFAULTPRINT((const u_char *)rhp, min(length, caplen));
+           ret = 1;
            break;
        }
+       return (ret);
+
+trunc:
+       return (0);
 }
 
 static void
-print_t_info(int info)
+print_t_info(netdissect_options *ndo,
+             int info)
 {
        int ntype = info & 3;
        switch (ntype) {
-       case 0: (void)printf("reserved-ntype? "); break;
-       case TI_L2ROUT: (void)printf("l2rout "); break;
-       case TI_L1ROUT: (void)printf("l1rout "); break;
-       case TI_ENDNODE: (void)printf("endnode "); break;
+       case 0: ND_PRINT((ndo, "reserved-ntype? ")); break;
+       case TI_L2ROUT: ND_PRINT((ndo, "l2rout ")); break;
+       case TI_L1ROUT: ND_PRINT((ndo, "l1rout ")); break;
+       case TI_ENDNODE: ND_PRINT((ndo, "endnode ")); break;
        }
        if (info & TI_VERIF)
-           (void)printf("verif ");
+           ND_PRINT((ndo, "verif "));
        if (info & TI_BLOCK)
-           (void)printf("blo ");
+           ND_PRINT((ndo, "blo "));
 }
 
-static void
-print_l1_routes(const char *rp, u_int len)
+static int
+print_l1_routes(netdissect_options *ndo,
+                const char *rp, u_int len)
 {
        int count;
        int id;
@@ -280,9 +772,10 @@ print_l1_routes(const char *rp, u_int len)
 
        /* The last short is a checksum */
        while (len > (3 * sizeof(short))) {
+           ND_TCHECK2(*rp, 3 * sizeof(short));
            count = EXTRACT_LE_16BITS(rp);
            if (count > 1024)
-               return; /* seems to be bogus from here on */
+               return (1);     /* seems to be bogus from here on */
            rp += sizeof(short);
            len -= sizeof(short);
            id = EXTRACT_LE_16BITS(rp);
@@ -291,13 +784,18 @@ print_l1_routes(const char *rp, u_int len)
            info = EXTRACT_LE_16BITS(rp);
            rp += sizeof(short);
            len -= sizeof(short);
-           (void)printf("{ids %d-%d cost %d hops %d} ", id, id + count,
-                           RI_COST(info), RI_HOPS(info));
+           ND_PRINT((ndo, "{ids %d-%d cost %d hops %d} ", id, id + count,
+                           RI_COST(info), RI_HOPS(info)));
        }
+       return (1);
+
+trunc:
+       return (0);
 }
 
-static void
-print_l2_routes(const char *rp, u_int len)
+static int
+print_l2_routes(netdissect_options *ndo,
+                const char *rp, u_int len)
 {
        int count;
        int area;
@@ -305,9 +803,10 @@ print_l2_routes(const char *rp, u_int len)
 
        /* The last short is a checksum */
        while (len > (3 * sizeof(short))) {
+           ND_TCHECK2(*rp, 3 * sizeof(short));
            count = EXTRACT_LE_16BITS(rp);
            if (count > 1024)
-               return; /* seems to be bogus from here on */
+               return (1);     /* seems to be bogus from here on */
            rp += sizeof(short);
            len -= sizeof(short);
            area = EXTRACT_LE_16BITS(rp);
@@ -316,41 +815,51 @@ print_l2_routes(const char *rp, u_int len)
            info = EXTRACT_LE_16BITS(rp);
            rp += sizeof(short);
            len -= sizeof(short);
-           (void)printf("{areas %d-%d cost %d hops %d} ", area, area + count,
-                           RI_COST(info), RI_HOPS(info));
+           ND_PRINT((ndo, "{areas %d-%d cost %d hops %d} ", area, area + count,
+                           RI_COST(info), RI_HOPS(info)));
        }
+       return (1);
+
+trunc:
+       return (0);
 }
 
 static void
-print_i_info(int info)
+print_i_info(netdissect_options *ndo,
+             int info)
 {
        int ntype = info & II_TYPEMASK;
        switch (ntype) {
-       case 0: (void)printf("reserved-ntype? "); break;
-       case II_L2ROUT: (void)printf("l2rout "); break;
-       case II_L1ROUT: (void)printf("l1rout "); break;
-       case II_ENDNODE: (void)printf("endnode "); break;
+       case 0: ND_PRINT((ndo, "reserved-ntype? ")); break;
+       case II_L2ROUT: ND_PRINT((ndo, "l2rout ")); break;
+       case II_L1ROUT: ND_PRINT((ndo, "l1rout ")); break;
+       case II_ENDNODE: ND_PRINT((ndo, "endnode ")); break;
        }
        if (info & II_VERIF)
-           (void)printf("verif ");
+           ND_PRINT((ndo, "verif "));
        if (info & II_NOMCAST)
-           (void)printf("nomcast ");
+           ND_PRINT((ndo, "nomcast "));
        if (info & II_BLOCK)
-           (void)printf("blo ");
+           ND_PRINT((ndo, "blo "));
 }
 
-static void
+static int
 print_elist(const char *elp _U_, u_int len _U_)
 {
        /* Not enough examples available for me to debug this */
+       return (1);
 }
 
-static void
-print_nsp(const u_char *nspp, u_int nsplen _U_)
+static int
+print_nsp(netdissect_options *ndo,
+          const u_char *nspp, u_int nsplen)
 {
-       const struct nsphdr *nsphp = (struct nsphdr *)nspp;
+       const struct nsphdr *nsphp = (const struct nsphdr *)nspp;
        int dst, src, flags;
 
+       if (nsplen < sizeof(struct nsphdr))
+               goto trunc;
+       ND_TCHECK(*nsphp);
        flags = EXTRACT_LE_8BITS(nsphp->nh_flags);
        dst = EXTRACT_LE_16BITS(nsphp->nh_dst);
        src = EXTRACT_LE_16BITS(nsphp->nh_src);
@@ -362,182 +871,219 @@ print_nsp(const u_char *nspp, u_int nsplen _U_)
            case MFS_MOM:
            case MFS_EOM:
            case MFS_BOM+MFS_EOM:
-               printf("data %d>%d ", src, dst);
+               ND_PRINT((ndo, "data %d>%d ", src, dst));
                {
-                   struct seghdr *shp = (struct seghdr *)nspp;
+                   const struct seghdr *shp = (const struct seghdr *)nspp;
                    int ack;
 #ifdef PRINT_NSPDATA
-                   u_char *dp;
+                   const u_char *dp;
 #endif
                    u_int data_off = sizeof(struct minseghdr);
 
+                   if (nsplen < data_off)
+                       goto trunc;
+                   ND_TCHECK(shp->sh_seq[0]);
                    ack = EXTRACT_LE_16BITS(shp->sh_seq[0]);
                    if (ack & SGQ_ACK) {        /* acknum field */
                        if ((ack & SGQ_NAK) == SGQ_NAK)
-                           (void)printf("nak %d ", ack & SGQ_MASK);
+                           ND_PRINT((ndo, "nak %d ", ack & SGQ_MASK));
                        else
-                           (void)printf("ack %d ", ack & SGQ_MASK);
-                       ack = EXTRACT_LE_16BITS(shp->sh_seq[1]);
+                           ND_PRINT((ndo, "ack %d ", ack & SGQ_MASK));
                        data_off += sizeof(short);
+                       if (nsplen < data_off)
+                           goto trunc;
+                       ND_TCHECK(shp->sh_seq[1]);
+                       ack = EXTRACT_LE_16BITS(shp->sh_seq[1]);
                        if (ack & SGQ_OACK) {   /* ackoth field */
                            if ((ack & SGQ_ONAK) == SGQ_ONAK)
-                               (void)printf("onak %d ", ack & SGQ_MASK);
+                               ND_PRINT((ndo, "onak %d ", ack & SGQ_MASK));
                            else
-                               (void)printf("oack %d ", ack & SGQ_MASK);
-                           ack = EXTRACT_LE_16BITS(shp->sh_seq[2]);
+                               ND_PRINT((ndo, "oack %d ", ack & SGQ_MASK));
                            data_off += sizeof(short);
+                           if (nsplen < data_off)
+                               goto trunc;
+                           ND_TCHECK(shp->sh_seq[2]);
+                           ack = EXTRACT_LE_16BITS(shp->sh_seq[2]);
                        }
                    }
-                   (void)printf("seg %d ", ack & SGQ_MASK);
+                   ND_PRINT((ndo, "seg %d ", ack & SGQ_MASK));
 #ifdef PRINT_NSPDATA
-                   dp = &(nspp[data_off]);
-                   pdata(dp, 10);
+                   if (nsplen > data_off) {
+                       dp = &(nspp[data_off]);
+                       ND_TCHECK2(*dp, nsplen - data_off);
+                       pdata(ndo, dp, nsplen - data_off);
+                   }
 #endif
                }
                break;
            case MFS_ILS+MFS_INT:
-               printf("intr ");
+               ND_PRINT((ndo, "intr "));
                {
-                   struct seghdr *shp = (struct seghdr *)nspp;
+                   const struct seghdr *shp = (const struct seghdr *)nspp;
                    int ack;
 #ifdef PRINT_NSPDATA
-                   u_char *dp;
+                   const u_char *dp;
 #endif
                    u_int data_off = sizeof(struct minseghdr);
 
+                   if (nsplen < data_off)
+                       goto trunc;
+                   ND_TCHECK(shp->sh_seq[0]);
                    ack = EXTRACT_LE_16BITS(shp->sh_seq[0]);
                    if (ack & SGQ_ACK) {        /* acknum field */
                        if ((ack & SGQ_NAK) == SGQ_NAK)
-                           (void)printf("nak %d ", ack & SGQ_MASK);
+                           ND_PRINT((ndo, "nak %d ", ack & SGQ_MASK));
                        else
-                           (void)printf("ack %d ", ack & SGQ_MASK);
-                       ack = EXTRACT_LE_16BITS(shp->sh_seq[1]);
+                           ND_PRINT((ndo, "ack %d ", ack & SGQ_MASK));
                        data_off += sizeof(short);
+                       if (nsplen < data_off)
+                           goto trunc;
+                       ND_TCHECK(shp->sh_seq[1]);
+                       ack = EXTRACT_LE_16BITS(shp->sh_seq[1]);
                        if (ack & SGQ_OACK) {   /* ackdat field */
                            if ((ack & SGQ_ONAK) == SGQ_ONAK)
-                               (void)printf("nakdat %d ", ack & SGQ_MASK);
+                               ND_PRINT((ndo, "nakdat %d ", ack & SGQ_MASK));
                            else
-                               (void)printf("ackdat %d ", ack & SGQ_MASK);
-                           ack = EXTRACT_LE_16BITS(shp->sh_seq[2]);
+                               ND_PRINT((ndo, "ackdat %d ", ack & SGQ_MASK));
                            data_off += sizeof(short);
+                           if (nsplen < data_off)
+                               goto trunc;
+                           ND_TCHECK(shp->sh_seq[2]);
+                           ack = EXTRACT_LE_16BITS(shp->sh_seq[2]);
                        }
                    }
-                   (void)printf("seg %d ", ack & SGQ_MASK);
+                   ND_PRINT((ndo, "seg %d ", ack & SGQ_MASK));
 #ifdef PRINT_NSPDATA
-                   dp = &(nspp[data_off]);
-                   pdata(dp, 10);
+                   if (nsplen > data_off) {
+                       dp = &(nspp[data_off]);
+                       ND_TCHECK2(*dp, nsplen - data_off);
+                       pdata(ndo, dp, nsplen - data_off);
+                   }
 #endif
                }
                break;
            case MFS_ILS:
-               (void)printf("link-service %d>%d ", src, dst);
+               ND_PRINT((ndo, "link-service %d>%d ", src, dst));
                {
-                   struct seghdr *shp = (struct seghdr *)nspp;
-                   struct lsmsg *lsmp =
-                       (struct lsmsg *)&(nspp[sizeof(struct seghdr)]);
+                   const struct seghdr *shp = (const struct seghdr *)nspp;
+                   const struct lsmsg *lsmp =
+                       (const struct lsmsg *)&(nspp[sizeof(struct seghdr)]);
                    int ack;
                    int lsflags, fcval;
 
+                   if (nsplen < sizeof(struct seghdr) + sizeof(struct lsmsg))
+                       goto trunc;
+                   ND_TCHECK(shp->sh_seq[0]);
                    ack = EXTRACT_LE_16BITS(shp->sh_seq[0]);
                    if (ack & SGQ_ACK) {        /* acknum field */
                        if ((ack & SGQ_NAK) == SGQ_NAK)
-                           (void)printf("nak %d ", ack & SGQ_MASK);
+                           ND_PRINT((ndo, "nak %d ", ack & SGQ_MASK));
                        else
-                           (void)printf("ack %d ", ack & SGQ_MASK);
+                           ND_PRINT((ndo, "ack %d ", ack & SGQ_MASK));
+                       ND_TCHECK(shp->sh_seq[1]);
                        ack = EXTRACT_LE_16BITS(shp->sh_seq[1]);
                        if (ack & SGQ_OACK) {   /* ackdat field */
                            if ((ack & SGQ_ONAK) == SGQ_ONAK)
-                               (void)printf("nakdat %d ", ack & SGQ_MASK);
+                               ND_PRINT((ndo, "nakdat %d ", ack & SGQ_MASK));
                            else
-                               (void)printf("ackdat %d ", ack & SGQ_MASK);
+                               ND_PRINT((ndo, "ackdat %d ", ack & SGQ_MASK));
+                           ND_TCHECK(shp->sh_seq[2]);
                            ack = EXTRACT_LE_16BITS(shp->sh_seq[2]);
                        }
                    }
-                   (void)printf("seg %d ", ack & SGQ_MASK);
+                   ND_PRINT((ndo, "seg %d ", ack & SGQ_MASK));
+                   ND_TCHECK(*lsmp);
                    lsflags = EXTRACT_LE_8BITS(lsmp->ls_lsflags);
                    fcval = EXTRACT_LE_8BITS(lsmp->ls_fcval);
                    switch (lsflags & LSI_MASK) {
                    case LSI_DATA:
-                       (void)printf("dat seg count %d ", fcval);
+                       ND_PRINT((ndo, "dat seg count %d ", fcval));
                        switch (lsflags & LSM_MASK) {
                        case LSM_NOCHANGE:
                            break;
                        case LSM_DONOTSEND:
-                           (void)printf("donotsend-data ");
+                           ND_PRINT((ndo, "donotsend-data "));
                            break;
                        case LSM_SEND:
-                           (void)printf("send-data ");
+                           ND_PRINT((ndo, "send-data "));
                            break;
                        default:
-                           (void)printf("reserved-fcmod? %x", lsflags);
+                           ND_PRINT((ndo, "reserved-fcmod? %x", lsflags));
                            break;
                        }
                        break;
                    case LSI_INTR:
-                       (void)printf("intr req count %d ", fcval);
+                       ND_PRINT((ndo, "intr req count %d ", fcval));
                        break;
                    default:
-                       (void)printf("reserved-fcval-int? %x", lsflags);
+                       ND_PRINT((ndo, "reserved-fcval-int? %x", lsflags));
                        break;
                    }
                }
                break;
            default:
-               (void)printf("reserved-subtype? %x %d > %d", flags, src, dst);
+               ND_PRINT((ndo, "reserved-subtype? %x %d > %d", flags, src, dst));
                break;
            }
            break;
        case MFT_ACK:
            switch (flags & NSP_SUBMASK) {
            case MFS_DACK:
-               (void)printf("data-ack %d>%d ", src, dst);
+               ND_PRINT((ndo, "data-ack %d>%d ", src, dst));
                {
-                   struct ackmsg *amp = (struct ackmsg *)nspp;
+                   const struct ackmsg *amp = (const struct ackmsg *)nspp;
                    int ack;
 
+                   if (nsplen < sizeof(struct ackmsg))
+                       goto trunc;
+                   ND_TCHECK(*amp);
                    ack = EXTRACT_LE_16BITS(amp->ak_acknum[0]);
                    if (ack & SGQ_ACK) {        /* acknum field */
                        if ((ack & SGQ_NAK) == SGQ_NAK)
-                           (void)printf("nak %d ", ack & SGQ_MASK);
+                           ND_PRINT((ndo, "nak %d ", ack & SGQ_MASK));
                        else
-                           (void)printf("ack %d ", ack & SGQ_MASK);
+                           ND_PRINT((ndo, "ack %d ", ack & SGQ_MASK));
                        ack = EXTRACT_LE_16BITS(amp->ak_acknum[1]);
                        if (ack & SGQ_OACK) {   /* ackoth field */
                            if ((ack & SGQ_ONAK) == SGQ_ONAK)
-                               (void)printf("onak %d ", ack & SGQ_MASK);
+                               ND_PRINT((ndo, "onak %d ", ack & SGQ_MASK));
                            else
-                               (void)printf("oack %d ", ack & SGQ_MASK);
+                               ND_PRINT((ndo, "oack %d ", ack & SGQ_MASK));
                        }
                    }
                }
                break;
            case MFS_IACK:
-               (void)printf("ils-ack %d>%d ", src, dst);
+               ND_PRINT((ndo, "ils-ack %d>%d ", src, dst));
                {
-                   struct ackmsg *amp = (struct ackmsg *)nspp;
+                   const struct ackmsg *amp = (const struct ackmsg *)nspp;
                    int ack;
 
+                   if (nsplen < sizeof(struct ackmsg))
+                       goto trunc;
+                   ND_TCHECK(*amp);
                    ack = EXTRACT_LE_16BITS(amp->ak_acknum[0]);
                    if (ack & SGQ_ACK) {        /* acknum field */
                        if ((ack & SGQ_NAK) == SGQ_NAK)
-                           (void)printf("nak %d ", ack & SGQ_MASK);
+                           ND_PRINT((ndo, "nak %d ", ack & SGQ_MASK));
                        else
-                           (void)printf("ack %d ", ack & SGQ_MASK);
+                           ND_PRINT((ndo, "ack %d ", ack & SGQ_MASK));
+                       ND_TCHECK(amp->ak_acknum[1]);
                        ack = EXTRACT_LE_16BITS(amp->ak_acknum[1]);
                        if (ack & SGQ_OACK) {   /* ackdat field */
                            if ((ack & SGQ_ONAK) == SGQ_ONAK)
-                               (void)printf("nakdat %d ", ack & SGQ_MASK);
+                               ND_PRINT((ndo, "nakdat %d ", ack & SGQ_MASK));
                            else
-                               (void)printf("ackdat %d ", ack & SGQ_MASK);
+                               ND_PRINT((ndo, "ackdat %d ", ack & SGQ_MASK));
                        }
                    }
                }
                break;
            case MFS_CACK:
-               (void)printf("conn-ack %d", dst);
+               ND_PRINT((ndo, "conn-ack %d", dst));
                break;
            default:
-               (void)printf("reserved-acktype? %x %d > %d", flags, src, dst);
+               ND_PRINT((ndo, "reserved-acktype? %x %d > %d", flags, src, dst));
                break;
            }
            break;
@@ -546,17 +1092,20 @@ print_nsp(const u_char *nspp, u_int nsplen _U_)
            case MFS_CI:
            case MFS_RCI:
                if ((flags & NSP_SUBMASK) == MFS_CI)
-                   (void)printf("conn-initiate ");
+                   ND_PRINT((ndo, "conn-initiate "));
                else
-                   (void)printf("retrans-conn-initiate ");
-               (void)printf("%d>%d ", src, dst);
+                   ND_PRINT((ndo, "retrans-conn-initiate "));
+               ND_PRINT((ndo, "%d>%d ", src, dst));
                {
-                   struct cimsg *cimp = (struct cimsg *)nspp;
+                   const struct cimsg *cimp = (const struct cimsg *)nspp;
                    int services, info, segsize;
 #ifdef PRINT_NSPDATA
-                   u_char *dp;
+                   const u_char *dp;
 #endif
 
+                   if (nsplen < sizeof(struct cimsg))
+                       goto trunc;
+                   ND_TCHECK(*cimp);
                    services = EXTRACT_LE_8BITS(cimp->ci_services);
                    info = EXTRACT_LE_8BITS(cimp->ci_info);
                    segsize = EXTRACT_LE_16BITS(cimp->ci_segsize);
@@ -565,46 +1114,52 @@ print_nsp(const u_char *nspp, u_int nsplen _U_)
                    case COS_NONE:
                        break;
                    case COS_SEGMENT:
-                       (void)printf("seg ");
+                       ND_PRINT((ndo, "seg "));
                        break;
                    case COS_MESSAGE:
-                       (void)printf("msg ");
+                       ND_PRINT((ndo, "msg "));
                        break;
                    case COS_CRYPTSER:
-                       (void)printf("crypt ");
+                       ND_PRINT((ndo, "crypt "));
                        break;
                    }
                    switch (info & COI_MASK) {
                    case COI_32:
-                       (void)printf("ver 3.2 ");
+                       ND_PRINT((ndo, "ver 3.2 "));
                        break;
                    case COI_31:
-                       (void)printf("ver 3.1 ");
+                       ND_PRINT((ndo, "ver 3.1 "));
                        break;
                    case COI_40:
-                       (void)printf("ver 4.0 ");
+                       ND_PRINT((ndo, "ver 4.0 "));
                        break;
                    case COI_41:
-                       (void)printf("ver 4.1 ");
+                       ND_PRINT((ndo, "ver 4.1 "));
                        break;
                    }
-                   (void)printf("segsize %d ", segsize);
+                   ND_PRINT((ndo, "segsize %d ", segsize));
 #ifdef PRINT_NSPDATA
-                   dp = &(nspp[sizeof(struct cimsg)]);
-                   pdata(dp, nsplen - sizeof(struct cimsg));
+                   if (nsplen > sizeof(struct cimsg)) {
+                       dp = &(nspp[sizeof(struct cimsg)]);
+                       ND_TCHECK2(*dp, nsplen - sizeof(struct cimsg));
+                       pdata(ndo, dp, nsplen - sizeof(struct cimsg));
+                   }
 #endif
                }
                break;
            case MFS_CC:
-               (void)printf("conn-confirm %d>%d ", src, dst);
+               ND_PRINT((ndo, "conn-confirm %d>%d ", src, dst));
                {
-                   struct ccmsg *ccmp = (struct ccmsg *)nspp;
+                   const struct ccmsg *ccmp = (const struct ccmsg *)nspp;
                    int services, info;
                    u_int segsize, optlen;
 #ifdef PRINT_NSPDATA
-                   u_char *dp;
+                   const u_char *dp;
 #endif
 
+                   if (nsplen < sizeof(struct ccmsg))
+                       goto trunc;
+                   ND_TCHECK(*ccmp);
                    services = EXTRACT_LE_8BITS(ccmp->cc_services);
                    info = EXTRACT_LE_8BITS(ccmp->cc_info);
                    segsize = EXTRACT_LE_16BITS(ccmp->cc_segsize);
@@ -614,87 +1169,99 @@ print_nsp(const u_char *nspp, u_int nsplen _U_)
                    case COS_NONE:
                        break;
                    case COS_SEGMENT:
-                       (void)printf("seg ");
+                       ND_PRINT((ndo, "seg "));
                        break;
                    case COS_MESSAGE:
-                       (void)printf("msg ");
+                       ND_PRINT((ndo, "msg "));
                        break;
                    case COS_CRYPTSER:
-                       (void)printf("crypt ");
+                       ND_PRINT((ndo, "crypt "));
                        break;
                    }
                    switch (info & COI_MASK) {
                    case COI_32:
-                       (void)printf("ver 3.2 ");
+                       ND_PRINT((ndo, "ver 3.2 "));
                        break;
                    case COI_31:
-                       (void)printf("ver 3.1 ");
+                       ND_PRINT((ndo, "ver 3.1 "));
                        break;
                    case COI_40:
-                       (void)printf("ver 4.0 ");
+                       ND_PRINT((ndo, "ver 4.0 "));
                        break;
                    case COI_41:
-                       (void)printf("ver 4.1 ");
+                       ND_PRINT((ndo, "ver 4.1 "));
                        break;
                    }
-                   (void)printf("segsize %d ", segsize);
+                   ND_PRINT((ndo, "segsize %d ", segsize));
                    if (optlen) {
-                       (void)printf("optlen %d ", optlen);
+                       ND_PRINT((ndo, "optlen %d ", optlen));
 #ifdef PRINT_NSPDATA
-                       optlen = min(optlen, nsplen - sizeof(struct ccmsg));
+                       if (optlen > nsplen - sizeof(struct ccmsg))
+                           goto trunc;
                        dp = &(nspp[sizeof(struct ccmsg)]);
-                       pdata(dp, optlen);
+                       ND_TCHECK2(*dp, optlen);
+                       pdata(ndo, dp, optlen);
 #endif
                    }
                }
                break;
            case MFS_DI:
-               (void)printf("disconn-initiate %d>%d ", src, dst);
+               ND_PRINT((ndo, "disconn-initiate %d>%d ", src, dst));
                {
-                   struct dimsg *dimp = (struct dimsg *)nspp;
+                   const struct dimsg *dimp = (const struct dimsg *)nspp;
                    int reason;
                    u_int optlen;
 #ifdef PRINT_NSPDATA
-                   u_char *dp;
+                   const u_char *dp;
 #endif
 
+                   if (nsplen < sizeof(struct dimsg))
+                       goto trunc;
+                   ND_TCHECK(*dimp);
                    reason = EXTRACT_LE_16BITS(dimp->di_reason);
                    optlen = EXTRACT_LE_8BITS(dimp->di_optlen);
 
-                   print_reason(reason);
+                   print_reason(ndo, reason);
                    if (optlen) {
-                       (void)printf("optlen %d ", optlen);
+                       ND_PRINT((ndo, "optlen %d ", optlen));
 #ifdef PRINT_NSPDATA
-                       optlen = min(optlen, nsplen - sizeof(struct dimsg));
+                       if (optlen > nsplen - sizeof(struct dimsg))
+                           goto trunc;
                        dp = &(nspp[sizeof(struct dimsg)]);
-                       pdata(dp, optlen);
+                       ND_TCHECK2(*dp, optlen);
+                       pdata(ndo, dp, optlen);
 #endif
                    }
                }
                break;
            case MFS_DC:
-               (void)printf("disconn-confirm %d>%d ", src, dst);
+               ND_PRINT((ndo, "disconn-confirm %d>%d ", src, dst));
                {
-                   struct dcmsg *dcmp = (struct dcmsg *)nspp;
+                   const struct dcmsg *dcmp = (const struct dcmsg *)nspp;
                    int reason;
 
+                   ND_TCHECK(*dcmp);
                    reason = EXTRACT_LE_16BITS(dcmp->dc_reason);
 
-                   print_reason(reason);
+                   print_reason(ndo, reason);
                }
                break;
            default:
-               (void)printf("reserved-ctltype? %x %d > %d", flags, src, dst);
+               ND_PRINT((ndo, "reserved-ctltype? %x %d > %d", flags, src, dst));
                break;
            }
            break;
        default:
-           (void)printf("reserved-type? %x %d > %d", flags, src, dst);
+           ND_PRINT((ndo, "reserved-type? %x %d > %d", flags, src, dst));
            break;
        }
+       return (1);
+
+trunc:
+       return (0);
 }
 
-static struct tok reason2str[] = {
+static const struct tok reason2str[] = {
        { UC_OBJREJECT,         "object rejected connect" },
        { UC_RESOURCES,         "insufficient resources" },
        { UC_NOSUCHNODE,        "unrecognized node name" },
@@ -721,13 +1288,14 @@ static struct tok reason2str[] = {
 };
 
 static void
-print_reason(register int reason)
+print_reason(netdissect_options *ndo,
+             register int reason)
 {
-       printf("%s ", tok2str(reason2str, "reason-%d", reason));
+       ND_PRINT((ndo, "%s ", tok2str(reason2str, "reason-%d", reason)));
 }
 
 const char *
-dnnum_string(u_short dnaddr)
+dnnum_string(netdissect_options *ndo, u_short dnaddr)
 {
        char *str;
        size_t siz;
@@ -736,35 +1304,41 @@ dnnum_string(u_short dnaddr)
 
        str = (char *)malloc(siz = sizeof("00.0000"));
        if (str == NULL)
-               error("dnnum_string: malloc");
+               (*ndo->ndo_error)(ndo, "dnnum_string: malloc");
        snprintf(str, siz, "%d.%d", area, node);
        return(str);
 }
 
 const char *
-dnname_string(u_short dnaddr)
+dnname_string(netdissect_options *ndo, u_short dnaddr)
 {
 #ifdef HAVE_DNET_HTOA
        struct dn_naddr dna;
+       char *dnname;
 
        dna.a_len = sizeof(short);
        memcpy((char *)dna.a_addr, (char *)&dnaddr, sizeof(short));
-       return (strdup(dnet_htoa(&dna)));
+       dnname = dnet_htoa(&dna);
+       if(dnname != NULL)
+               return (strdup(dnname));
+       else
+               return(dnnum_string(ndo, dnaddr));
 #else
-       return(dnnum_string(dnaddr));   /* punt */
+       return(dnnum_string(ndo, dnaddr));      /* punt */
 #endif
 }
 
 #ifdef PRINT_NSPDATA
 static void
-pdata(u_char *dp, u_int maxlen)
+pdata(netdissect_options *ndo,
+      u_char *dp, u_int maxlen)
 {
        char c;
        u_int x = maxlen;
 
        while (x-- > 0) {
            c = *dp++;
-           safeputchar(c);
+           safeputchar(ndo, c);
        }
 }
 #endif