Ethereal-dev: [Ethereal-dev] BGP support for L2VPNs
Note: This archive is from the project's previous web site, ethereal.com. This list is no longer active.
From: Hannes Gredler <hannes@xxxxxxxxxxx>
Date: Mon, 26 Aug 2002 23:52:54 +0200
hi ethereal developers, pls find attached a patch for more complete support for L2VPNs like described in draft-kompella-ppvpn-l2vpn; fixing a segfault in the extd_community decoder; more consistent SAFI strings (tcpdump) more robust V6 decoding (the assumption that v6 may come only in unlabeled form is wrong :-|) /hannes
Index: packet-bgp.c
===================================================================
RCS file: /cvsroot/ethereal/packet-bgp.c,v
retrieving revision 1.64
diff -u -r1.64 packet-bgp.c
--- packet-bgp.c 2002/08/24 21:58:57 1.64
+++ packet-bgp.c 2002/08/26 21:46:06
@@ -203,9 +203,9 @@
{ SAFNUM_MULCAST, "Multicast" },
{ SAFNUM_UNIMULC, "Unicast+Multicast" },
{ SAFNUM_MPLS_LABEL, "MPLS Labeled Prefix"},
- { SAFNUM_LAB_VPNUNICAST, "Labeled Unicast" }, /* draft-rosen-rfc2547bis-03 */
- { SAFNUM_LAB_VPNMULCAST, "Labeled Multicast" },
- { SAFNUM_LAB_VPNUNIMULC, "Labeled Unicast+Multicast" },
+ { SAFNUM_LAB_VPNUNICAST, "Labeled VPN Unicast" }, /* draft-rosen-rfc2547bis-03 */
+ { SAFNUM_LAB_VPNMULCAST, "Labeled VPN Multicast" },
+ { SAFNUM_LAB_VPNUNIMULC, "Labeled VPN Unicast+Multicast" },
{ 0, NULL },
};
@@ -333,6 +333,8 @@
return(1 + length);
}
+
+
/*
* Decode an MPLS label stack
*/
@@ -415,7 +417,7 @@
case FORMAT_IP_LOC:
length = 12;
tvb_memcpy(tvb, ip4addr, offset + 2, 4); /* IP part of the RD */
- tvb_memcpy(tvb, ip4addr2, offset +6, 4); /* IP address of the VPN-IPv4 */
+ tvb_memcpy(tvb, ip4addr2, offset +6, 4); /* IP address of the VPN */
snprintf(buf, buflen, "Empty Label Stack RD=%s:%u IP=%s",
ip_to_str(ip4addr),
tvb_get_ntohs(tvb, offset + 6),
@@ -423,21 +425,47 @@
break ;
default:
length = 0 ;
- snprintf(buf, buflen, "Unknown labeled VPN-IPv4 address format");
+ snprintf(buf, buflen, "Unknown (0x%04x)labeled VPN address format",rd_type);
break;
}
break;
default:
- length = 0 ;
- snprintf(buf, buflen, "Unknown SAFI (%u) for AFI %u", safi, afi);
- break;
+ length = 0 ;
+ snprintf(buf, buflen, "Unknown SAFI (%u) for AFI %u", safi, afi);
+ break;
}
break;
case AFNUM_INET6:
- length = 16 ;
- tvb_memcpy(tvb, ip6addr.u6_addr.u6_addr8,offset, sizeof(ip6addr));
- snprintf(buf, buflen, "%s", ip6_to_str(&ip6addr));
+ switch (safi) {
+ case SAFNUM_UNICAST: /* only decode unlabeled prefixes */
+ case SAFNUM_MULCAST:
+ case SAFNUM_UNIMULC:
+ length = 16 ;
+ tvb_memcpy(tvb, ip6addr.u6_addr.u6_addr8,offset, sizeof(ip6addr));
+ snprintf(buf, buflen, "%s", ip6_to_str(&ip6addr));
+ break;
+ default:
+ length = 0 ;
+ snprintf(buf, buflen, "Unknown SAFI (%u) for AFI %u", safi, afi);
+ break;
+ }
break;
+ case AFNUM_L2VPN:
+ switch (safi) {
+ case SAFNUM_LAB_VPNUNICAST: /* only labeles prefixes do make sense */
+ case SAFNUM_LAB_VPNMULCAST:
+ case SAFNUM_LAB_VPNUNIMULC:
+ length = 4; /* the next-hop is simply an ipv4 addr */
+ tvb_memcpy(tvb, ip4addr, offset + 0, 4);
+ snprintf(buf, buflen, "IP=%s",
+ ip_to_str(ip4addr));
+ break;
+ default:
+ length = 0 ;
+ snprintf(buf, buflen, "Unknown SAFI (%u) for AFI %u", safi, afi);
+ break;
+ }
+ break;
default:
length = 0 ;
snprintf(buf, buflen, "Unknown AFI (%u) value", afi);
@@ -455,6 +483,7 @@
int length; /* length of the prefix in byte */
int plen; /* length of the prefix in bit */
int labnum; /* number of labels */
+ int ce_id,labblk_off;
guint8 ip4addr[4],ip4addr2[4]; /* IPv4 address */
guint16 rd_type; /* Route Distinguisher type */
char lab_stk[256]; /* label stack */
@@ -551,7 +580,7 @@
break ;
default:
length = 0 ;
- snprintf(buf,buflen, "Unknown labeled VPN address format");
+ snprintf(buf,buflen, "Unknown labeled VPN address format");
break;
}
break;
@@ -562,8 +591,62 @@
}
break;
case AFNUM_INET6:
- length = decode_prefix6(tvb, offset, buf, buflen) - 1 ;
- break;
+ switch (safi) {
+ case SAFNUM_UNICAST:
+ case SAFNUM_MULCAST:
+ case SAFNUM_UNIMULC:
+ length = decode_prefix6(tvb, offset, buf, buflen) - 1 ;
+ break;
+ default:
+ length = 0 ;
+ snprintf(buf,buflen, "Unknown SAFI (%u) for AFI %u", safi, afi);
+ break;
+ }
+ break;
+ case AFNUM_L2VPN:
+ switch (safi) {
+ case SAFNUM_LAB_VPNUNICAST:
+ case SAFNUM_LAB_VPNMULCAST:
+ case SAFNUM_LAB_VPNUNIMULC:
+ plen = tvb_get_ntohs(tvb,offset);
+ rd_type=tvb_get_ntohs(tvb,offset+2);
+ ce_id=tvb_get_ntohs(tvb,offset+10);
+ labblk_off=tvb_get_ntohs(tvb,offset+12);
+ labnum = decode_MPLS_stack(tvb, offset + 14, lab_stk, sizeof(lab_stk));
+
+ switch (rd_type) {
+ case FORMAT_AS2_LOC:
+ tvb_memcpy(tvb, ip4addr, offset + 6, 4);
+ snprintf(buf,buflen, "RD: %u:%s, CE-ID: %u, Label-Block Offset: %u, Label Base %s",
+ tvb_get_ntohs(tvb, offset + 4),
+ ip_to_str(ip4addr),
+ ce_id,
+ labblk_off,
+ lab_stk);
+ break ;
+ case FORMAT_IP_LOC:
+ tvb_memcpy(tvb, ip4addr, offset + 4, 4);
+ snprintf(buf,buflen, "RD: %s:%u, CE-ID: %u, Label-Block Offset: %u, Label Base %s",
+ ip_to_str(ip4addr),
+ tvb_get_ntohs(tvb, offset + 8),
+ ce_id,
+ labblk_off,
+ lab_stk);
+ break ;
+ default:
+ length = 0 ;
+ snprintf(buf,buflen, "Unknown labeled VPN address format");
+ break;
+ }
+ /* FIXME there are subTLVs left to decode ... for now lets omit them */
+ length=plen+1; /* should be 2 but length+1 is returned at the end */
+ break;
+ default:
+ length = 0 ;
+ snprintf(buf, buflen, "Unknown SAFI (%u) for AFI %u", safi, afi);
+ break;
+ }
+ break;
default:
length = 0 ;
snprintf(buf,buflen, "Unknown AFI (%u) value", afi);
@@ -864,8 +947,8 @@
char *as_path_str = NULL; /* AS_PATH string */
char *communities_str = NULL; /* COMMUNITIES string */
char *cluster_list_str = NULL; /* CLUSTER_LIST string */
- char *ext_com_str = NULL; /* EXTENDED COMMUNITY list */
char junk_buf[256]; /* tmp */
+ int junk_buf_len; /* tmp len */
guint8 ipaddr[4]; /* IPv4 address */
hlen = tvb_get_ntohs(tvb, offset + BGP_MARKER_SIZE);
@@ -1138,22 +1221,20 @@
(o + current attribute + aoff bytes to first tuple) */
q = o + i + aoff;
end = q + tlen;
- ext_com_str = malloc((tlen / 8)*MAX_SIZE_OF_EXT_COM_NAMES);
- if (ext_com_str == NULL) break;
- ext_com_str[0] = '\0';
+ junk_buf_len=0;
while (q < end) {
ext_com = tvb_get_ntohs(tvb, q);
- snprintf(junk_buf, sizeof(junk_buf), "%s", val_to_str(ext_com,bgpext_com_type,"Unknown"));
- strncat(ext_com_str, junk_buf, sizeof(junk_buf));
+ junk_buf_len=snprintf(junk_buf+junk_buf_len,sizeof(junk_buf),"%s",
+ val_to_str(ext_com,bgpext_com_type,"Unknown"));
q = q + 8;
- if (q < end) strncat(ext_com_str, ",", 1);
+ if (q < end) junk_buf_len=snprintf(junk_buf+junk_buf_len, sizeof(junk_buf)-junk_buf_len, ", ");
}
+ junk_buf[junk_buf_len]='\0';
ti = proto_tree_add_text(subtree,tvb,o+i,tlen+aoff,
"%s: %s (%u %s)",
val_to_str(bgpa.bgpa_type,bgpattr_type,"Unknown"),
- ext_com_str, tlen + aoff,
+ junk_buf, tlen + aoff,
(tlen + aoff == 1) ? "byte" : "bytes");
- free(ext_com_str);
break;
default:
@@ -1460,7 +1541,7 @@
"Subsequent address family identifier: %s (%u)",
val_to_str(saf, bgpattr_nlri_safi, saf >= 128 ? "Vendor specific" : "Unknown"),
saf);
- if (af != AFNUM_INET && af != AFNUM_INET6) {
+ if (af != AFNUM_INET && af != AFNUM_INET6 && af != AFNUM_L2VPN) {
/*
* The addresses don't contain lengths, so if we
* don't understand the address family type, we
@@ -1512,7 +1593,7 @@
}
tlen -= off;
aoff += off;
-
+
ti = proto_tree_add_text(subtree2, tvb, o + i + aoff, tlen,
"Network layer reachability information (%u %s)",
tlen, (tlen == 1) ? "byte" : "bytes");
@@ -1549,10 +1630,10 @@
while (tlen > 0) {
advance = decode_prefix_MP(af, saf, tvb, o + i + aoff , junk_buf, sizeof(junk_buf)) ;
proto_tree_add_text(subtree3, tvb, o + i + aoff, advance, "%s", junk_buf) ;
- if (advance==1) /* catch if this is a unknown AFI type*/
- break;
tlen -= advance;
aoff += advance;
+ if (advance==1) /* catch if this is a unknown AFI type*/
+ break;
}
}
break;
@@ -1594,63 +1675,64 @@
} else {
q = o + i + aoff ;
end = o + i + aoff + tlen ;
- ext_com_str = malloc(MAX_SIZE_OF_EXT_COM_NAMES+MAX_SIZE_OF_IP_ADDR_STRING*2+1) ;
- if (ext_com_str == NULL) break ;
ti = proto_tree_add_text(subtree2,tvb,q,tlen, "Carried Extended communities");
subtree3 = proto_item_add_subtree(ti,ett_bgp_extended_communities) ;
+ junk_buf_len=0;
while (q < end) {
- ext_com_str[0] = '\0' ;
ext_com = tvb_get_ntohs(tvb,q) ;
- snprintf(junk_buf, sizeof(junk_buf), "%s", val_to_str(ext_com,bgpext_com_type,"Unknown"));
- strncat(ext_com_str,junk_buf,sizeof(junk_buf));
+ junk_buf_len=snprintf(junk_buf+junk_buf_len, sizeof(junk_buf), "%s",
+ val_to_str(ext_com,bgpext_com_type,"Unknown"));
switch (ext_com) {
case BGP_EXT_COM_RT_0:
case BGP_EXT_COM_RO_0:
- snprintf(junk_buf, sizeof(junk_buf), ": %u%s%d",tvb_get_ntohs(tvb,q+2),":",tvb_get_ntohl(tvb,q+4));
+ junk_buf_len+=snprintf(junk_buf+junk_buf_len, sizeof(junk_buf)-junk_buf_len, ": %u%s%d",
+ tvb_get_ntohs(tvb,q+2),":",tvb_get_ntohl(tvb,q+4));
break ;
case BGP_EXT_COM_RT_1:
case BGP_EXT_COM_RO_1:
tvb_memcpy(tvb,ipaddr,q+2,4);
- snprintf(junk_buf, sizeof(junk_buf), ": %s%s%u",ip_to_str(ipaddr),":",tvb_get_ntohs(tvb,q+6));
+ junk_buf_len+=snprintf(junk_buf+junk_buf_len, sizeof(junk_buf)-junk_buf_len, ": %s%s%u",
+ ip_to_str(ipaddr),":",tvb_get_ntohs(tvb,q+6));
break;
case BGP_EXT_COM_VPN_ORIGIN:
case BGP_EXT_COM_OSPF_RID:
tvb_memcpy(tvb,ipaddr,q+2,4);
- snprintf(junk_buf, sizeof(junk_buf), ": %s",ip_to_str(ipaddr));
+ junk_buf_len+=snprintf(junk_buf+junk_buf_len, sizeof(junk_buf)-junk_buf_len, ": %s",
+ ip_to_str(ipaddr));
break;
case BGP_EXT_COM_OSPF_RTYPE:
tvb_memcpy(tvb,ipaddr,q+2,4);
- snprintf(junk_buf, sizeof(junk_buf), ": Area:%s %s",
+ junk_buf_len+=snprintf(junk_buf+junk_buf_len, sizeof(junk_buf)-junk_buf_len, ": Area:%s %s",
ip_to_str(ipaddr),
val_to_str(tvb_get_guint8(tvb,q+6),bgpext_ospf_rtype,"Unknown"));
/* print OSPF Metric type if selected */
/* always print E2 even if not external route -- receiving router should ignore */
if ( (tvb_get_guint8(tvb,q+7)) & BGP_OSPF_RTYPE_METRIC_TYPE ) {
- strcat(junk_buf," E2");
+ junk_buf_len+=snprintf(junk_buf+junk_buf_len,sizeof(junk_buf)-junk_buf_len," E2");
} else if (tvb_get_guint8(tvb,q+6)==(BGP_OSPF_RTYPE_EXT ||BGP_OSPF_RTYPE_NSSA ) ) {
- strcat(junk_buf, " E1");
+ junk_buf_len+=snprintf(junk_buf+junk_buf_len,sizeof(junk_buf)-junk_buf_len," E1");
}
break;
case BGP_EXT_COM_LINKBAND:
tvb_memcpy(tvb,ipaddr,q+2,4); /* need to check on IEEE format on all platforms */
- snprintf(junk_buf, sizeof(junk_buf), ": %f bytes per second",(double)*ipaddr);
+ junk_buf_len+=snprintf(junk_buf+junk_buf_len, sizeof(junk_buf)-junk_buf_len, ": %.3f Mbps",
+ ((double)*ipaddr)*8/1000000);
break;
case BGP_EXT_COM_L2INFO:
- snprintf(junk_buf, sizeof(junk_buf), ": %s:Control Flags [0x%02x]:MTU %u",
+ junk_buf_len+=snprintf(junk_buf+junk_buf_len, sizeof(junk_buf)-junk_buf_len, ": %s:Control Flags [0x%02x]:MTU %u",
val_to_str(tvb_get_guint8(tvb,q+2),bgp_l2vpn_encaps,"Unknown"),
tvb_get_guint8(tvb,q+3),
tvb_get_ntohs(tvb,q+4));
break;
default:
- snprintf(junk_buf, sizeof(junk_buf), " ");
+ junk_buf_len+=snprintf(junk_buf+junk_buf_len, sizeof(junk_buf)-junk_buf_len, " ");
break ;
- }
- strncat(ext_com_str,junk_buf,sizeof(junk_buf));
- proto_tree_add_text(subtree3,tvb,q,8, "%s",ext_com_str);
- q = q + 8 ;
+ }
+ junk_buf[junk_buf_len]='\0';
+ proto_tree_add_text(subtree3,tvb,q,8, "%s",junk_buf);
+ q = q + 8 ;
}
- free(ext_com_str) ;
}
break;
default:
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