]> The Tcpdump Group git mirrors - tcpdump/commitdiff
Add bounds checking.
authorguy <guy>
Wed, 24 Mar 2004 00:01:00 +0000 (00:01 +0000)
committerguy <guy>
Wed, 24 Mar 2004 00:01:00 +0000 (00:01 +0000)
print-bgp.c

index 62355ed4641bbd46330e454af40cc50496ae61ac..6760f25060864112e523c79f2ec31af63716da8f 100644 (file)
@@ -36,7 +36,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-     "@(#) $Header: /tcpdump/master/tcpdump/print-bgp.c,v 1.80 2004-03-18 11:14:45 hannes Exp $";
+     "@(#) $Header: /tcpdump/master/tcpdump/print-bgp.c,v 1.81 2004-03-24 00:01:00 guy Exp $";
 #endif
 
 #include <tcpdump-stdinc.h>
@@ -466,11 +466,13 @@ decode_prefix4(const u_char *pptr, char *buf, u_int buflen)
        struct in_addr addr;
        u_int plen;
 
+       TCHECK(pptr[0]);
        plen = pptr[0];
        if (32 < plen)
                return -1;
 
        memset(&addr, 0, sizeof(addr));
+       TCHECK2(pptr[1], (plen + 7) / 8);
        memcpy(&addr, &pptr[1], (plen + 7) / 8);
        if (plen % 8) {
                ((u_char *)&addr)[(plen + 7) / 8 - 1] &=
@@ -478,6 +480,9 @@ decode_prefix4(const u_char *pptr, char *buf, u_int buflen)
        }
        snprintf(buf, buflen, "%s/%d", getname((u_char *)&addr), plen);
        return 1 + (plen + 7) / 8;
+
+trunc:
+       return -2;
 }
 
 static int
@@ -486,6 +491,7 @@ decode_labeled_prefix4(const u_char *pptr, char *buf, u_int buflen)
        struct in_addr addr;
        u_int plen;
 
+       TCHECK(pptr[0]);
        plen = pptr[0];   /* get prefix length */
 
         /* this is one of the weirdnesses of rfc3107
@@ -502,6 +508,7 @@ decode_labeled_prefix4(const u_char *pptr, char *buf, u_int buflen)
                return -1;
 
        memset(&addr, 0, sizeof(addr));
+       TCHECK2(pptr[4], (plen + 7) / 8);
        memcpy(&addr, &pptr[4], (plen + 7) / 8);
        if (plen % 8) {
                ((u_char *)&addr)[(plen + 7) / 8 - 1] &=
@@ -515,6 +522,9 @@ decode_labeled_prefix4(const u_char *pptr, char *buf, u_int buflen)
                  ((pptr[3]&1)==0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
 
        return 4 + (plen + 7) / 8;
+
+trunc:
+       return -2;
 }
 
 /* RDs and RTs share the same semantics
@@ -563,6 +573,7 @@ decode_rt_routing_info(const u_char *pptr, char *buf, u_int buflen)
        u_int8_t route_target[8];
        u_int plen;
 
+       TCHECK(pptr[0]);
        plen = pptr[0];   /* get prefix length */
 
         plen-=32; /* adjust prefix length */
@@ -571,6 +582,7 @@ decode_rt_routing_info(const u_char *pptr, char *buf, u_int buflen)
                return -1;
 
        memset(&route_target, 0, sizeof(route_target));
+       TCHECK2(pptr[1], (plen + 7) / 8);
        memcpy(&route_target, &pptr[1], (plen + 7) / 8);
        if (plen % 8) {
                ((u_char *)&route_target)[(plen + 7) / 8 - 1] &=
@@ -581,6 +593,9 @@ decode_rt_routing_info(const u_char *pptr, char *buf, u_int buflen)
                  bgp_vpn_rd_print((u_char *)&route_target));
 
        return 5 + (plen + 7) / 8;
+
+trunc:
+       return -2;
 }
 
 static int
@@ -589,6 +604,7 @@ decode_labeled_vpn_prefix4(const u_char *pptr, char *buf, u_int buflen)
        struct in_addr addr;
        u_int plen;
 
+       TCHECK(pptr[0]);
        plen = pptr[0];   /* get prefix length */
 
         plen-=(24+64); /* adjust prefixlen - labellength - RD len*/
@@ -597,6 +613,7 @@ decode_labeled_vpn_prefix4(const u_char *pptr, char *buf, u_int buflen)
                return -1;
 
        memset(&addr, 0, sizeof(addr));
+       TCHECK2(pptr[12], (plen + 7) / 8);
        memcpy(&addr, &pptr[12], (plen + 7) / 8);
        if (plen % 8) {
                ((u_char *)&addr)[(plen + 7) / 8 - 1] &=
@@ -611,15 +628,21 @@ decode_labeled_vpn_prefix4(const u_char *pptr, char *buf, u_int buflen)
                  ((pptr[3]&1)==0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
 
        return 12 + (plen + 7) / 8;
+
+trunc:
+       return -2;
 }
 
 static int
 decode_labeled_vpn_l2(const u_char *pptr, char *buf, u_int buflen)
 {
         int plen,tlen,strlen,tlv_type,tlv_len,ttlv_len;
+
+       TCHECK2(pptr[0], 2);
         plen=EXTRACT_16BITS(pptr);
         tlen=plen;
         pptr+=2;
+       TCHECK2(pptr[0],15);
         strlen=snprintf(buf, buflen, "RD: %s, CE-ID: %u, Label-Block Offset: %u, Label Base %u",
                         bgp_vpn_rd_print(pptr),
                         EXTRACT_16BITS(pptr+8),
@@ -630,6 +653,9 @@ decode_labeled_vpn_l2(const u_char *pptr, char *buf, u_int buflen)
 
         /* ok now the variable part - lets read out TLVs*/
         while (tlen>0) {
+            if (tlen < 3)
+                return -1;
+            TCHECK2(pptr[0], 3);
             tlv_type=*pptr++;
             tlv_len=EXTRACT_16BITS(pptr);
             ttlv_len=tlv_len;
@@ -642,6 +668,7 @@ decode_labeled_vpn_l2(const u_char *pptr, char *buf, u_int buflen)
                                  tlv_len);
                 ttlv_len=ttlv_len/8+1; /* how many bytes do we need to read ? */
                 while (ttlv_len>0) {
+                    TCHECK(pptr[0]);
                     strlen+=snprintf(buf+strlen,buflen-strlen, "%02x",*pptr++);
                     ttlv_len--;
                 }
@@ -655,6 +682,9 @@ decode_labeled_vpn_l2(const u_char *pptr, char *buf, u_int buflen)
             tlen-=(tlv_len<<3); /* the tlv-length is expressed in bits so lets shift it tright */
         }
         return plen+2;
+
+trunc:
+        return -2;
 }
 
 #ifdef INET6
@@ -664,11 +694,13 @@ decode_prefix6(const u_char *pd, char *buf, u_int buflen)
        struct in6_addr addr;
        u_int plen;
 
+       TCHECK(pd[0]);
        plen = pd[0];
        if (128 < plen)
                return -1;
 
        memset(&addr, 0, sizeof(addr));
+       TCHECK2(pd[1], (plen + 7) / 8);
        memcpy(&addr, &pd[1], (plen + 7) / 8);
        if (plen % 8) {
                addr.s6_addr[(plen + 7) / 8 - 1] &=
@@ -676,6 +708,9 @@ decode_prefix6(const u_char *pd, char *buf, u_int buflen)
        }
        snprintf(buf, buflen, "%s/%d", getname6((u_char *)&addr), plen);
        return 1 + (plen + 7) / 8;
+
+trunc:
+       return -2;
 }
 
 static int
@@ -684,6 +719,7 @@ decode_labeled_prefix6(const u_char *pptr, char *buf, u_int buflen)
        struct in6_addr addr;
        u_int plen;
 
+       TCHECK(pptr[0]);
        plen = pptr[0]; /* get prefix length */
         plen-=24; /* adjust prefixlen - labellength */
 
@@ -691,6 +727,7 @@ decode_labeled_prefix6(const u_char *pptr, char *buf, u_int buflen)
                return -1;
 
        memset(&addr, 0, sizeof(addr));
+       TCHECK2(pptr[4], (plen + 7) / 8);
        memcpy(&addr, &pptr[4], (plen + 7) / 8);
        if (plen % 8) {
                addr.s6_addr[(plen + 7) / 8 - 1] &=
@@ -704,6 +741,9 @@ decode_labeled_prefix6(const u_char *pptr, char *buf, u_int buflen)
                  ((pptr[3]&1)==0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
 
        return 4 + (plen + 7) / 8;
+
+trunc:
+       return -2;
 }
 
 static int
@@ -712,6 +752,7 @@ decode_labeled_vpn_prefix6(const u_char *pptr, char *buf, u_int buflen)
        struct in6_addr addr;
        u_int plen;
 
+       TCHECK(pptr[0]);
        plen = pptr[0];   /* get prefix length */
 
         plen-=(24+64); /* adjust prefixlen - labellength - RD len*/
@@ -720,6 +761,7 @@ decode_labeled_vpn_prefix6(const u_char *pptr, char *buf, u_int buflen)
                return -1;
 
        memset(&addr, 0, sizeof(addr));
+       TCHECK2(pptr[12], (plen + 7) / 8);
        memcpy(&addr, &pptr[12], (plen + 7) / 8);
        if (plen % 8) {
                addr.s6_addr[(plen + 7) / 8 - 1] &=
@@ -734,10 +776,13 @@ decode_labeled_vpn_prefix6(const u_char *pptr, char *buf, u_int buflen)
                  ((pptr[3]&1)==0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
 
        return 12 + (plen + 7) / 8;
+
+trunc:
+       return -2;
 }
 #endif
 
-static void
+static int
 bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
 {
        int i;
@@ -759,8 +804,10 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
        case BGPTYPE_ORIGIN:
                if (len != 1)
                        printf("invalid len");
-               else
+               else {
+                       TCHECK(*tptr);
                        printf("%s", tok2str(bgp_origin_values, "Unknown Origin Typecode", tptr[0]));
+               }
                break;
        case BGPTYPE_AS_PATH:
                if (len % 2) {
@@ -773,26 +820,34 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                 }
 
                while (tptr < pptr + len) {
+                       TCHECK(tptr[0]);
                         printf("%s", tok2str(bgp_as_path_segment_open_values, "?", tptr[0]));
                         for (i = 0; i < tptr[1] * 2; i += 2) {
+                            TCHECK2(tptr[2 + i], 2);
                             printf("%u ", EXTRACT_16BITS(&tptr[2 + i]));
                         }
+                       TCHECK(tptr[0]);
                         printf("%s", tok2str(bgp_as_path_segment_close_values, "?", tptr[0]));
+                        TCHECK(tptr[1]);
                         tptr += 2 + tptr[1] * 2;
                }
                break;
        case BGPTYPE_NEXT_HOP:
                if (len != 4)
                        printf("invalid len");
-               else
+               else {
+                       TCHECK2(tptr[0], 4);
                        printf("%s", getname(tptr));
+               }
                break;
        case BGPTYPE_MULTI_EXIT_DISC:
        case BGPTYPE_LOCAL_PREF:
                if (len != 4)
                        printf("invalid len");
-               else
+               else {
+                       TCHECK2(tptr[0], 4);
                        printf("%u", EXTRACT_32BITS(tptr));
+               }
                break;
        case BGPTYPE_ATOMIC_AGGREGATE:
                if (len != 0)
@@ -803,6 +858,7 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                        printf("invalid len");
                        break;
                }
+               TCHECK2(tptr[0], 6);
                printf(" AS #%u, origin %s", EXTRACT_16BITS(tptr),
                        getname(tptr + 2));
                break;
@@ -813,6 +869,7 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                }
                while (tlen>0) {
                        u_int32_t comm;
+                       TCHECK2(tptr[0], 4);
                        comm = EXTRACT_32BITS(tptr);
                        switch (comm) {
                        case BGP_COMMUNITY_NO_EXPORT:
@@ -840,10 +897,16 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                        printf("invalid len");
                        break;
                }
+               TCHECK2(tptr[0], 4);
                 printf("%s",getname(tptr));
                 break;
         case BGPTYPE_CLUSTER_LIST:
+               if (len % 4) {
+                       printf("invalid len");
+                       break;
+               }
                 while (tlen>0) {
+                       TCHECK2(tptr[0], 4);
                         printf("%s%s",
                                getname(tptr),
                                 (tlen>4) ? ", " : "");
@@ -852,6 +915,7 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                 }
                 break;
        case BGPTYPE_MP_REACH_NLRI:
+               TCHECK2(tptr[0], 3);
                af = EXTRACT_16BITS(tptr);
                safi = tptr[2];
        
@@ -877,6 +941,7 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
 
                 tptr +=3;
 
+               TCHECK(tptr[0]);
                tlen = tptr[0];
                 tptr++;
 
@@ -891,23 +956,38 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                                     case SAFNUM_UNIMULTICAST:
                                     case SAFNUM_LABUNICAST:
                                     case SAFNUM_RT_ROUTING_INFO:
-                                       printf("%s",getname(tptr));
-                                       tlen -= sizeof(struct in_addr);
-                                        tptr += sizeof(struct in_addr);
+                                       if (tlen < (int)sizeof(struct in_addr)) {
+                                           printf("invalid len");
+                                           tlen = 0;
+                                       } else {
+                                           TCHECK2(tptr[0], sizeof(struct in_addr));
+                                           printf("%s",getname(tptr));
+                                           tlen -= sizeof(struct in_addr);
+                                           tptr += sizeof(struct in_addr);
+                                       }
                                        break;
                                     case SAFNUM_VPNUNICAST:
                                     case SAFNUM_VPNMULTICAST:
                                     case SAFNUM_VPNUNIMULTICAST:
-                                        printf("RD: %s, %s",
+                                       if (tlen < (int)(sizeof(struct in_addr)+BGP_VPN_RD_LEN)) {
+                                           printf("invalid len");
+                                           tlen = 0;
+                                       } else {
+                                           TCHECK2(tptr[0], sizeof(struct in_addr)+BGP_VPN_RD_LEN);
+                                           printf("RD: %s, %s",
                                                bgp_vpn_rd_print(tptr),
                                                getname(tptr+BGP_VPN_RD_LEN));
-                                       tlen -= (sizeof(struct in_addr)+BGP_VPN_RD_LEN);
-                                        tptr += (sizeof(struct in_addr)+BGP_VPN_RD_LEN);
+                                           tlen -= (sizeof(struct in_addr)+BGP_VPN_RD_LEN);
+                                           tptr += (sizeof(struct in_addr)+BGP_VPN_RD_LEN);
+                                       }
                                         break;
                                     default:
-                                        printf("no SAFI %u decoder",safi);                                        
+                                        TCHECK2(tptr[0], tlen);
+                                        printf("no SAFI %u decoder",safi);
                                         if (vflag <= 1)
                                             print_unknown_data(tptr,"\n\t    ",tlen);
+                                        tptr += tlen;
+                                        tlen = 0;
                                         break;
                                     }
                                     break;
@@ -919,23 +999,38 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                                     case SAFNUM_UNIMULTICAST:
                                     case SAFNUM_LABUNICAST:
                                     case SAFNUM_RT_ROUTING_INFO:
-                                        printf("%s", getname6(tptr));
-                                        tlen -= sizeof(struct in6_addr);
-                                        tptr += sizeof(struct in6_addr);
+                                       if (tlen < (int)sizeof(struct in6_addr)) {
+                                           printf("invalid len");
+                                           tlen = 0;
+                                       } else {
+                                           TCHECK2(tptr[0], sizeof(struct in6_addr));
+                                           printf("%s", getname6(tptr));
+                                           tlen -= sizeof(struct in6_addr);
+                                           tptr += sizeof(struct in6_addr);
+                                       }
                                         break;
                                     case SAFNUM_VPNUNICAST:
                                     case SAFNUM_VPNMULTICAST:
                                     case SAFNUM_VPNUNIMULTICAST:
-                                        printf("RD: %s, %s",
+                                       if (tlen < (int)(sizeof(struct in6_addr)+BGP_VPN_RD_LEN)) {
+                                           printf("invalid len");
+                                           tlen = 0;
+                                       } else {
+                                           TCHECK2(tptr[0], sizeof(struct in6_addr)+BGP_VPN_RD_LEN);
+                                           printf("RD: %s, %s",
                                                bgp_vpn_rd_print(tptr),
                                                getname6(tptr+BGP_VPN_RD_LEN));
-                                       tlen -= (sizeof(struct in6_addr)+BGP_VPN_RD_LEN);
-                                        tptr += (sizeof(struct in6_addr)+BGP_VPN_RD_LEN);
+                                           tlen -= (sizeof(struct in6_addr)+BGP_VPN_RD_LEN);
+                                           tptr += (sizeof(struct in6_addr)+BGP_VPN_RD_LEN);
+                                       }
                                         break;
                                     default:
+                                        TCHECK2(tptr[0], tlen);
                                         printf("no SAFI %u decoder",safi);
                                         if (vflag <= 1)
                                             print_unknown_data(tptr,"\n\t    ",tlen);                                        
+                                        tptr += tlen;
+                                        tlen = 0;
                                         break;
                                     }
                                     break;
@@ -945,39 +1040,53 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                                     case SAFNUM_VPNUNICAST:
                                     case SAFNUM_VPNMULTICAST:
                                     case SAFNUM_VPNUNIMULTICAST:
-                                        printf("%s", getname(tptr));
-                                       tlen -= (sizeof(struct in_addr));
-                                        tptr += (sizeof(struct in_addr));
-                                        break;                                   
+                                       if (tlen < (int)sizeof(struct in_addr)) {
+                                           printf("invalid len");
+                                           tlen = 0;
+                                       } else {
+                                           TCHECK2(tptr[0], sizeof(struct in_addr));
+                                           printf("%s", getname(tptr));
+                                           tlen -= (sizeof(struct in_addr));
+                                           tptr += (sizeof(struct in_addr));
+                                       }
+                                        break;
                                    default:
+                                        TCHECK2(tptr[0], tlen);
                                         printf("no SAFI %u decoder",safi);
                                         if (vflag <= 1)
                                             print_unknown_data(tptr,"\n\t    ",tlen);                                        
+                                        tptr += tlen;
+                                        tlen = 0;
                                         break;
                                    }
                                    break;
 
                                default:
+                                    TCHECK2(tptr[0], tlen);
                                     printf("no AFI %u decoder",af);
                                     if (vflag <= 1)
                                       print_unknown_data(tptr,"\n\t    ",tlen);
+                                    tptr += tlen;
+                                    tlen = 0;
                                     break;
                                }
                        }
                }
                tptr += tlen;
 
+               TCHECK(tptr[0]);
                snpa = tptr[0];
                tptr++;
 
                if (snpa) {
                        printf("\n\t    %u SNPA", snpa);
                        for (/*nothing*/; snpa > 0; snpa--) {
+                               TCHECK(tptr[0]);
                                printf("\n\t      %d bytes", tptr[0]);
                                tptr += tptr[0] + 1;
                        }
                } else {
-                printf(", no SNPA");
+                       printf(", no SNPA");
                 }
 
                while (len - (tptr - pptr) > 0) {
@@ -988,26 +1097,44 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                             case SAFNUM_MULTICAST:
                             case SAFNUM_UNIMULTICAST:
                                 advance = decode_prefix4(tptr, buf, sizeof(buf));
-                               if (advance >= 0)
+                               if (advance == -1)
+                                        printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                        goto trunc;
+                               else
                                        printf("\n\t      %s", buf);
-                               else 
-                                       printf("\n\t    (illegal prefix length)");
                                 break;
                             case SAFNUM_LABUNICAST:
                                 advance = decode_labeled_prefix4(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                        printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                        goto trunc;
+                               else
+                                        printf("\n\t      %s", buf);
                                 break;
                             case SAFNUM_VPNUNICAST:
                             case SAFNUM_VPNMULTICAST:
                             case SAFNUM_VPNUNIMULTICAST:
                                 advance = decode_labeled_vpn_prefix4(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                        printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                        goto trunc;
+                               else
+                                        printf("\n\t      %s", buf);
                                 break;
                             case SAFNUM_RT_ROUTING_INFO:
                                 advance = decode_rt_routing_info(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                        printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                        goto trunc;
+                               else
+                                        printf("\n\t      %s", buf);
                                 break;
                             default:
+                                TCHECK2(*(tptr-3),tlen);
                                 printf("\n\t      no SAFI %u decoder",safi);
                                 if (vflag <= 1)
                                     print_unknown_data(tptr-3,"\n\t    ",tlen);
@@ -1023,23 +1150,44 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                             case SAFNUM_MULTICAST:
                             case SAFNUM_UNIMULTICAST:
                                advance = decode_prefix6(tptr, buf, sizeof(buf));
-                               printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                       printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                       goto trunc;
+                               else
+                                       printf("\n\t      %s", buf);
                                break;
                             case SAFNUM_LABUNICAST:
                                 advance = decode_labeled_prefix6(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                       printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                       goto trunc;
+                               else
+                                       printf("\n\t      %s", buf);
                                 break;
                             case SAFNUM_VPNUNICAST:
                             case SAFNUM_VPNMULTICAST:
                             case SAFNUM_VPNUNIMULTICAST:
                                 advance = decode_labeled_vpn_prefix6(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                       printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                       goto trunc;
+                               else
+                                       printf("\n\t      %s", buf);
                                 break;
                             case SAFNUM_RT_ROUTING_INFO:
                                 advance = decode_rt_routing_info(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                       printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                       goto trunc;
+                               else
+                                       printf("\n\t      %s", buf);
                                 break;
                             default:
+                                TCHECK2(*(tptr-3),tlen);
                                 printf("\n\t      no SAFI %u decoder ",safi);
                                 if (vflag <= 1)
                                     print_unknown_data(tptr-3,"\n\t    ",tlen);
@@ -1055,12 +1203,18 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                             case SAFNUM_VPNMULTICAST:
                             case SAFNUM_VPNUNIMULTICAST:
                                advance = decode_labeled_vpn_l2(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);         
+                               if (advance == -1)
+                                       printf("\n\t    (illegal length)");
+                               else if (advance == -2)
+                                       goto trunc;
+                               else
+                                        printf("\n\t      %s", buf);         
                                 break;                                   
                             default:
+                                TCHECK2(*tptr,tlen);
                                 printf("no SAFI %u decoder",safi);
                                 if (vflag <= 1)
-                                    print_unknown_data(tptr,"\n\t    ",tlen);                                        
+                                    print_unknown_data(tptr,"\n\t    ",tlen);
                                 advance = 0;
                                tptr = pptr + len;
                                 break;
@@ -1069,6 +1223,7 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
 
 
                        default:
+                            TCHECK2(*(tptr-3),tlen);
                             printf("\n\t      no AFI %u decoder ",af);
                             if (vflag <= 1)
                                     print_unknown_data(tptr-3,"\n\t    ",tlen);
@@ -1081,6 +1236,7 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                break;
 
        case BGPTYPE_MP_UNREACH_NLRI:
+               TCHECK2(tptr[0], 3);
                af = EXTRACT_16BITS(tptr);
                safi = tptr[2];
 
@@ -1101,22 +1257,35 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                             case SAFNUM_MULTICAST:
                             case SAFNUM_UNIMULTICAST:
                                 advance = decode_prefix4(tptr, buf, sizeof(buf));
-                               if (advance >= 0) 
+                               if (advance == -1)
+                                        printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                        goto trunc;
+                               else
                                        printf("\n\t      %s", buf);
-                               else
-                                       printf("\n\t    (illegal prefix length)");
                                 break;
                             case SAFNUM_LABUNICAST:
                                 advance = decode_labeled_prefix4(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                        printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                        goto trunc;
+                               else
+                                        printf("\n\t      %s", buf);
                                 break;
                             case SAFNUM_VPNUNICAST:
                             case SAFNUM_VPNMULTICAST:
                             case SAFNUM_VPNUNIMULTICAST:
                                 advance = decode_labeled_vpn_prefix4(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                        printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                        goto trunc;
+                               else
+                                        printf("\n\t      %s", buf);
                                 break;
                             default:
+                                TCHECK2(*(tptr-3),tlen);
                                 printf("\n\t      no SAFI %u decoder",safi);
                                 if (vflag <= 1)
                                     print_unknown_data(tptr-3,"\n\t    ",tlen);
@@ -1133,19 +1302,35 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                             case SAFNUM_MULTICAST:
                             case SAFNUM_UNIMULTICAST:
                                advance = decode_prefix6(tptr, buf, sizeof(buf));
-                               printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                       printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                       goto trunc;
+                               else
+                                       printf("\n\t      %s", buf);
                                break;
                             case SAFNUM_LABUNICAST:
                                 advance = decode_labeled_prefix6(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                       printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                       goto trunc;
+                               else
+                                        printf("\n\t      %s", buf);
                                 break;
                             case SAFNUM_VPNUNICAST:
                             case SAFNUM_VPNMULTICAST:
                             case SAFNUM_VPNUNIMULTICAST:
                                 advance = decode_labeled_vpn_prefix6(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);
+                               if (advance == -1)
+                                       printf("\n\t    (illegal prefix length)");
+                               else if (advance == -2)
+                                       goto trunc;
+                               else
+                                        printf("\n\t      %s", buf);
                                 break;
                             default:
+                                TCHECK2(*(tptr-3),tlen);
                                 printf("\n\t      no SAFI %u decoder",safi);
                                 if (vflag <= 1)
                                     print_unknown_data(tptr-3,"\n\t    ",tlen);
@@ -1162,9 +1347,15 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                             case SAFNUM_VPNMULTICAST:
                             case SAFNUM_VPNUNIMULTICAST:
                                advance = decode_labeled_vpn_l2(tptr, buf, sizeof(buf));
-                                printf("\n\t      %s", buf);         
+                               if (advance == -1)
+                                       printf("\n\t    (illegal length)");
+                               else if (advance == -2)
+                                       goto trunc;
+                               else
+                                        printf("\n\t      %s", buf);         
                                 break;                                   
                             default:
+                                TCHECK2(*(tptr-3),tlen);
                                 printf("no SAFI %u decoder",safi);
                                 if (vflag <= 1)
                                     print_unknown_data(tptr-3,"\n\t    ",tlen);                                        
@@ -1175,6 +1366,7 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                             break;
 
                        default:
+                               TCHECK2(*(tptr-3),tlen);
                                printf("\n\t    no AFI %u decoder",af);
                                 if (vflag <= 1)
                                     print_unknown_data(tptr-3,"\n\t    ",tlen);
@@ -1193,6 +1385,8 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                }
                 while (tlen>0) {
                     u_int16_t extd_comm;
+
+                    TCHECK2(tptr[0], 2);
                     extd_comm=EXTRACT_16BITS(tptr);
 
                    printf("\n\t    %s (0x%04x), Flags [%s]",
@@ -1200,6 +1394,7 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                           extd_comm,
                           bittok2str(bgp_extd_comm_flag_values, "none", extd_comm));
 
+                    TCHECK2(*(tptr+2), 6);
                     switch(extd_comm) {
                     case BGP_EXT_COM_RT_0:
                     case BGP_EXT_COM_RO_0:
@@ -1265,6 +1460,7 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                 break;
 
         case BGPTYPE_ATTR_SET:
+                TCHECK2(tptr[0], 4);
                 printf("\n\t    Origin AS: %u", EXTRACT_32BITS(tptr));
                 tptr+=4;
                 len -=4;
@@ -1273,6 +1469,7 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                     int alen;
                     struct bgp_attr bgpa;
                     
+                    TCHECK2(tptr[0], sizeof(bgpa));
                     memcpy(&bgpa, tptr, sizeof(bgpa));
                     alen = bgp_attr_len(&bgpa);
                     tptr += bgp_attr_off(&bgpa);
@@ -1293,7 +1490,9 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
                             printf("+%x", bgpa.bgpa_flags & 0xf);
                         printf("]: ");
                     }
-                    bgp_attr_print(&bgpa, tptr, alen); /* FIXME check for recursion */
+                    /* FIXME check for recursion */
+                    if (!bgp_attr_print(&bgpa, tptr, alen))
+                        return 0;
                     tptr += alen;
                     len -= alen;
                }
@@ -1301,6 +1500,7 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
            
 
        default:
+           TCHECK2(*pptr,len);
             printf("\n\t    no Attribute %u decoder",attr->bgpa_type); /* we have no decoder for the attribute */
             if (vflag <= 1)
                 print_unknown_data(pptr,"\n\t    ",len);
@@ -1308,6 +1508,10 @@ bgp_attr_print(const struct bgp_attr *attr, const u_char *pptr, int len)
        }
         if (vflag > 1 && len) /* omit zero length attributes*/
             print_unknown_data(pptr,"\n\t    ",len);
+        return 1;
+
+trunc:
+        return 0;
 }
 
 static void
@@ -1448,12 +1652,14 @@ bgp_update_print(const u_char *dat, int length)
 
                while(i < 2 + len) {
                        wpfx = decode_prefix4(&p[i], buf, sizeof(buf));
-                       if (wpfx >= 0) {
-                               i += wpfx;
-                               printf("\n\t    %s", buf);
-                       } else {
+                       if (wpfx == -1) {
                                printf("\n\t    (illegal prefix length)");
                                break;
+                       } else if (wpfx == -2)
+                               goto trunc;
+                       else {
+                               i += wpfx;
+                               printf("\n\t    %s", buf);
                        }
                }
 #endif
@@ -1488,7 +1694,8 @@ bgp_update_print(const u_char *dat, int length)
                                        printf("+%x", bgpa.bgpa_flags & 0xf);
                                printf("]: ");
                        }
-                       bgp_attr_print(&bgpa, &p[i + aoff], alen);
+                       if (!bgp_attr_print(&bgpa, &p[i + aoff], alen))
+                               goto trunc;
                        i += aoff + alen;
                }
        }
@@ -1499,12 +1706,13 @@ bgp_update_print(const u_char *dat, int length)
                while (dat + length > p) {
                        char buf[MAXHOSTNAMELEN + 100];
                        i = decode_prefix4(p, buf, sizeof(buf));
-                       if (i >= 0) {
+                       if (i == -1)
+                               printf("\n\t    (illegal prefix length)");
+                       else if (i == -2)
+                               goto trunc;
+                       else {
                                printf("\n\t    %s", buf);
                                p += i;
-                       } else {
-                               printf("\n\t    (illegal prefix length)");
-                               break;
                        }
                }
        }
@@ -1601,7 +1809,7 @@ bgp_route_refresh_print(const u_char *pptr, int len) {
         return;
 }
 
-static void
+static int
 bgp_header_print(const u_char *dat, int length)
 {
        struct bgp bgp;
@@ -1634,9 +1842,10 @@ bgp_header_print(const u_char *dat, int length)
             print_unknown_data(dat,"\n\t  ",length);
                 break;
        }
-       return;
+       return 1;
 trunc:
        printf("[|BGP]");
+       return 0;
 }
 
 void
@@ -1693,7 +1902,8 @@ bgp_print(const u_char *dat, int length)
                }
 
                if (TTEST2(p[0], hlen)) {
-                       bgp_header_print(p, hlen);
+                       if (!bgp_header_print(p, hlen))
+                               return;
                        p += hlen;
                        start = p;
                } else {