Added support for two new TLVs to IS-IS

The IS-IS listener now supports two new LSP TLVs:
 * Extended IS Reachability (code 22)
 * Extended IP Reachability (code 135)

Author: garberg

isis.py

@@ -650,6 +650,36 @@ def parseVLenField(ftype, flen, fval, verbose=1, level=0):
 
                 fval = fval[16:]
 
+        elif ftype == VLEN_FIELDS["TEIISNeighbor"]:
+            ## 22
+            rv["V"] = []
+            cnt = 0
+            while len(fval) > 0:
+                cnt = cnt + 1
+                (nid, psn, m1, m2, m3, s_tlv_len) =\
+                    struct.unpack("> 6sBBBBB", fval[0:11])
+                fval = fval[11:]
+
+                metric = (m1 << 16) | (m2 << 8) | m3
+
+                node = {
+                    'NID': nid,
+                    'PSEUDONODE': psn,
+                    'METRIC': metric,
+                    'SUB_TLV_LEN': s_tlv_len
+                }
+
+                rv["V"].append(node)
+
+                # Handling of sub TLVs will come later
+                if s_tlv_len > 0:
+                    fval = fval[s_tlv_len:]
+
+                if verbose > 0:
+                    print level*INDENT +\
+                          "IS Neighbour %d: %s, pseudonode: %d, metric: %d" % (cnt, str2hex(nid), psn, metric)
+
+
         elif ftype == VLEN_FIELDS["IPIntReach"]:
             ## 128
             rv["V"] = []
@@ -731,6 +761,43 @@ def parseVLenField(ftype, flen, fval, verbose=1, level=0):
             if verbose > 0:
                 print level*INDENT + "interface IP addresses: " + `addrs_strs`
 
+        elif ftype == VLEN_FIELDS["TEIPReach"]:
+            ## 135
+            rv["V"] = []
+
+            while len(fval) > 0:
+                assert len(fval) >= 5
+                metric, control = struct.unpack("> iB", fval[:5])
+                fval = fval[5:]
+                up = bool(control & 1 << 7)
+                sub_tlvs = bool(control & 1 << 6)
+                preflen = int(control & 63)
+
+                assert preflen <= 32 and preflen >= 0
+
+                if preflen == 0:
+                    prefix = "0.0.0.0/0"
+                else:
+                    n_octets = (preflen - 1)/8 + 1
+                    prefix_data = struct.unpack("> %dB" % n_octets, fval[:n_octets])
+                    fval = fval[n_octets:]
+
+                    prefix = ".".join([ "%d" % d for d in prefix_data ])
+                    prefix += ".".join([ '0' for i in range(4 - n_octets) ])
+                    prefix += "/%d" % preflen
+
+                if verbose > 0:
+                    print level*INDENT + "prefix: %s metric: %d up: %s sub TLVs: %s" % (prefix, metric, str(up), str(sub_tlvs))
+
+                prefix_reach = {
+                    'METRIC': metric,
+                    'UP': up,
+                    'SUB_TLVS': sub_tlvs,
+                    'PREFIX': prefix
+                }
+
+                rv["V"].append(prefix_reach)
+
         elif ftype == VLEN_FIELDS["DynamicHostname"]:
             ## 137
             name = struct.unpack("> %ds" % flen, fval)