Initial revision

1 files changed, 2478 insertions, 0 deletions

diff --git a/isisd/isis_pdu.c b/isisd/isis_pdu.c
new file mode 100644
index 00000000..8d636b30
--- /dev/null
+++ b/isisd/isis_pdu.c
@@ -0,0 +1,2478 @@
+/*
+ * IS-IS Rout(e)ing protocol - isis_pdu.c   
+ *                             PDU processing
+ *
+ * Copyright (C) 2001,2002   Sampo Saaristo
+ *                           Tampere University of Technology      
+ *                           Institute of Communications Engineering
+ *
+ * This program is free software; you can redistribute it and/or modify it 
+ * under the terms of the GNU General Public Licenseas published by the Free 
+ * Software Foundation; either version 2 of the License, or (at your option) 
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,but WITHOUT 
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for 
+ * more details.
+
+ * You should have received a copy of the GNU General Public License along 
+ * with this program; if not, write to the Free Software Foundation, Inc., 
+ * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <zebra.h>
+#include <net/ethernet.h>
+
+#include "memory.h"
+#include "thread.h"
+#include "linklist.h"
+#include "log.h"
+#include "stream.h"
+#include "vty.h"
+#include "hash.c"
+#include "prefix.h"
+#include "if.h"
+
+#include "isisd/dict.h"
+#include "isisd/include-netbsd/iso.h"
+#include "isisd/isis_constants.h"
+#include "isisd/isis_common.h"
+#include "isisd/isis_adjacency.h"
+#include "isisd/isis_circuit.h"
+#include "isisd/isis_network.h"
+#include "isisd/isis_misc.h"
+#include "isisd/isis_dr.h"
+#include "isisd/isis_flags.h"
+#include "isisd/isis_tlv.h"
+#include "isisd/isisd.h"
+#include "isisd/isis_dynhn.h"
+#include "isisd/isis_lsp.h"
+#include "isisd/isis_pdu.h"
+#include "isisd/iso_checksum.h"
+#include "isisd/isis_csm.h"
+#include "isisd/isis_events.h"
+
+extern struct thread_master *master;
+extern struct isis *isis;
+
+#define ISIS_MINIMUM_FIXED_HDR_LEN 15
+#define ISIS_MIN_PDU_LEN           13 /* partial seqnum pdu with id_len=2 */
+
+#ifndef PNBBY
+#define PNBBY 8
+#endif /* PNBBY */
+
+/* Utility mask array. */
+static u_char maskbit[] = 
+{
+  0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff
+};
+
+/*
+ * HELPER FUNCS
+ */
+
+/*
+ * Compares two sets of area addresses
+ */
+static int 
+area_match (struct list *left, struct list *right)
+{
+  struct area_addr *addr1, *addr2;
+  struct listnode *node1, *node2;
+
+  LIST_LOOP (left, addr1, node1) {
+    LIST_LOOP (right, addr2, node2) {
+      if (addr1->addr_len == addr2->addr_len && 
+        !memcmp (addr1->area_addr, addr2->area_addr, (int)addr1->addr_len))
+        return 1; /* match */
+    }
+  }
+
+  return 0; /* mismatch */
+}
+
+/*
+ * Check if ip2 is in the ip1's network (function like Prefix.h:prefix_match() )
+ * param ip1            the IS interface ip address structure
+ * param ip2            the IIH's ip address
+ * return  0            the IIH's IP is not in the IS's subnetwork
+ *         1            the IIH's IP is in the IS's subnetwork
+ */
+int
+ip_same_subnet  (struct prefix_ipv4 *ip1, struct in_addr *ip2)
+{
+  u_char *addr1, *addr2;
+  int shift, offset;
+  int len;
+    
+  addr1 = (u_char *) &ip1->prefix.s_addr;
+  addr2 = (u_char *) &ip2->s_addr;
+  len = ip1->prefixlen;
+
+  shift = len % PNBBY;
+  offset = len / PNBBY;
+
+  while (offset--) {
+    if (addr1[offset] != addr2[offset]) {
+      return 0;
+    }
+  }
+
+  if (shift) {
+    if (maskbit[shift] & (addr1[offset] ^ addr2[offset])) {
+      return 0;
+    }
+  }
+    
+ return 1; /* match  */
+}
+
+
+/*
+ * Compares two set of ip addresses
+ * param left     the local interface's ip addresses
+ * param right    the iih interface's ip address
+ * return         0   no match;
+ *                1   match;
+ */
+static int 
+ip_match (struct list *left, struct list *right)
+{
+  struct prefix_ipv4 *ip1;
+  struct in_addr *ip2;
+  struct listnode *node1, *node2;
+
+  LIST_LOOP (left, ip1, node1) {
+    LIST_LOOP (right, ip2, node2) {
+      if (ip_same_subnet(ip1, ip2)) {
+        return 1;  /* match */
+      }
+    }
+  
+  }
+  return 0;
+}
+
+/*
+ * Checks whether we should accept a PDU of given level 
+ */
+static int
+accept_level (int level, int circuit_t)
+{
+  int retval = ((circuit_t & level) == level); /* simple approach */
+
+  return retval;
+}
+
+int 
+authentication_check (struct isis_passwd *one, struct isis_passwd *theother)
+{
+  if (one->type != theother->type) {
+    zlog_warn ("Unsupported authentication type %d", theother->type );
+    return 1; /* Auth fail (different authentication types)*/
+  }
+  switch (one->type) {
+  case ISIS_PASSWD_TYPE_CLEARTXT:
+    if (one->len != theother->len)
+      return 1; /* Auth fail () - passwd len mismatch */
+    return memcmp (one->passwd, theother->passwd, one->len);
+    break;
+  default:
+    zlog_warn ("Unsupported authentication type");
+    break;
+  }
+  return 0; /* Auth pass */ 
+}
+
+/*
+ * Processing helper functions
+ */
+void
+tlvs_to_adj_nlpids (struct tlvs *tlvs, struct isis_adjacency *adj) 
+{
+  int i;
+  struct nlpids *tlv_nlpids;
+
+  if (tlvs->nlpids) {
+
+    tlv_nlpids = tlvs->nlpids;
+
+    adj->nlpids.count = tlv_nlpids->count;
+
+    for (i=0;i<tlv_nlpids->count;i++) {
+       adj->nlpids.nlpids[i] = tlv_nlpids->nlpids[i];
+    }
+  }
+}
+
+void  
+del_ip_addr (void *val)
+{
+  XFREE (MTYPE_ISIS_TMP, val);
+}
+
+void
+tlvs_to_adj_ipv4_addrs (struct tlvs *tlvs, struct isis_adjacency *adj) 
+{
+  struct listnode *node;
+  struct in_addr *ipv4_addr, *malloced;
+
+  if (adj->ipv4_addrs) {
+    adj->ipv4_addrs->del = del_ip_addr;
+    list_delete (adj->ipv4_addrs);
+  }
+  adj->ipv4_addrs = list_new ();
+  if (tlvs->ipv4_addrs) {
+    LIST_LOOP (tlvs->ipv4_addrs, ipv4_addr, node) {
+      malloced = XMALLOC (MTYPE_ISIS_TMP, sizeof (struct in_addr));
+      memcpy (malloced, ipv4_addr, sizeof (struct in_addr));
+      listnode_add (adj->ipv4_addrs, malloced);
+    }
+  }
+}
+
+#ifdef HAVE_IPV6
+void
+tlvs_to_adj_ipv6_addrs (struct tlvs *tlvs, struct isis_adjacency *adj) 
+{
+  struct listnode *node;
+  struct in6_addr *ipv6_addr, *malloced;
+
+  if (adj->ipv6_addrs) {
+    adj->ipv6_addrs->del = del_ip_addr;
+    list_delete (adj->ipv6_addrs);
+  }
+  adj->ipv6_addrs = list_new ();
+  if (tlvs->ipv6_addrs) {
+    LIST_LOOP (tlvs->ipv6_addrs, ipv6_addr, node) {
+      malloced = XMALLOC (MTYPE_ISIS_TMP, sizeof (struct in6_addr));
+      memcpy (malloced, ipv6_addr, sizeof (struct in6_addr));
+      listnode_add (adj->ipv6_addrs, malloced);
+    }
+  }
+
+}
+#endif /* HAVE_IPV6 */
+
+
+
+/*
+ *  RECEIVE SIDE                           
+ */
+
+/*
+ * Process P2P IIH
+ * ISO - 10589
+ * Section 8.2.5 - Receiving point-to-point IIH PDUs
+ *
+ */
+static int
+process_p2p_hello (struct isis_circuit *circuit)
+{
+  int retval = ISIS_OK;
+  struct isis_p2p_hello_hdr *hdr;
+  struct isis_adjacency *adj;
+  u_int32_t expected = 0, found;
+  struct tlvs tlvs;
+
+  if ((stream_get_endp (circuit->rcv_stream) - 
+       stream_get_getp (circuit->rcv_stream)) <
+      ISIS_P2PHELLO_HDRLEN) {
+    zlog_warn ("Packet too short");
+    return ISIS_WARNING;
+  }
+
+  /* 8.2.5.1 PDU acceptance tests */
+
+  /* 8.2.5.1 a) external domain untrue */
+  /* FIXME: not useful at all?         */
+
+  /* 8.2.5.1 b) ID Length mismatch */
+  /* checked at the handle_pdu     */
+
+  /* 8.2.5.2 IIH PDU Processing */
+
+  /* 8.2.5.2 a) 1) Maximum Area Addresses */
+  /* Already checked, and can also be ommited */
+
+  /*
+   * Get the header
+   */
+  hdr = (struct isis_p2p_hello_hdr*) STREAM_PNT(circuit->rcv_stream);
+  circuit->rcv_stream->getp += ISIS_P2PHELLO_HDRLEN;
+
+  /*  hdr.circuit_t = stream_getc (stream);
+      stream_get (hdr.source_id, stream, ISIS_SYS_ID_LEN);
+      hdr.hold_time = stream_getw (stream);
+      hdr.pdu_len   = stream_getw (stream);
+      hdr.local_id  = stream_getc (stream); */
+
+  /*
+   * My interpertation of the ISO, if no adj exists we will create one for 
+   * the circuit
+   */
+
+  if (isis->debugs  & DEBUG_ADJ_PACKETS) {
+     zlog_info("ISIS-Adj (%s): Rcvd P2P IIH from (%s), cir type %s,"
+	       " cir id %02d, length %d",
+	       circuit->area->area_tag, circuit->interface->name, 
+	       circuit_t2string(circuit->circuit_is_type),
+	       circuit->circuit_id,ntohs(hdr->pdu_len));
+  }
+
+  adj = circuit->u.p2p.neighbor;
+  if ( !adj ) {
+    adj = isis_new_adj (hdr->source_id,"      ", 0, circuit);
+    if (adj == NULL)
+      return ISIS_ERROR;
+    circuit->u.p2p.neighbor = adj;
+    isis_adj_state_change(adj, ISIS_ADJ_INITIALIZING, NULL);
+    adj->sys_type = ISIS_SYSTYPE_UNKNOWN;
+  }
+
+  /* 8.2.6 Monitoring point-to-point adjacencies */
+  adj->hold_time = ntohs (hdr->hold_time);
+  adj->last_upd  = time (NULL);
+
+  /*
+   * Lets get the TLVS now
+   */
+  expected |= TLVFLAG_AREA_ADDRS;
+  expected |= TLVFLAG_AUTH_INFO;
+  expected |= TLVFLAG_NLPID;
+  expected |= TLVFLAG_IPV4_ADDR;
+  expected |= TLVFLAG_IPV6_ADDR;
+
+  retval = parse_tlvs (circuit->area->area_tag,
+		       STREAM_PNT (circuit->rcv_stream),
+		       ntohs (hdr->pdu_len) - ISIS_P2PHELLO_HDRLEN 
+		       - ISIS_FIXED_HDR_LEN,
+		       &expected,
+		       &found,
+		       &tlvs);
+
+  if (retval > ISIS_WARNING) {
+    free_tlvs (&tlvs);
+    return retval;
+  };
+
+  /* 8.2.5.1 c) Authentication */
+  if (circuit->passwd.type) {
+    if (!(found & TLVFLAG_AUTH_INFO) || 
+	authentication_check (&circuit->passwd, &tlvs.auth_info)) {
+      isis_event_auth_failure (circuit->area->area_tag, 
+			       "P2P hello authentication failure", 
+			       hdr->source_id);
+      return ISIS_OK;
+    }
+  }
+
+  /* we do this now because the adj may not survive till the end... */
+
+  /* we need to copy addresses to the adj */
+  tlvs_to_adj_ipv4_addrs (&tlvs,adj);
+
+#ifdef HAVE_IPV6
+  tlvs_to_adj_ipv6_addrs (&tlvs,adj);
+#endif /* HAVE_IPV6 */
+
+  /* lets take care of the expiry */
+  if(adj->t_expire) {
+    thread_cancel (adj->t_expire);
+  }
+  adj->t_expire = thread_add_timer (master, isis_adj_expire, adj,
+                                    (long)adj->hold_time);
+
+  /* 8.2.5.2 a) a match was detected */
+  if (area_match (circuit->area->area_addrs, tlvs.area_addrs)) {
+    /* 8.2.5.2 a) 2) If the system is L1 - table 5 */
+    if (circuit->area->is_type == IS_LEVEL_1) {
+      switch (hdr->circuit_t) {
+      case IS_LEVEL_1:
+      case IS_LEVEL_1_AND_2:
+        if (adj->adj_state != ISIS_ADJ_UP) {
+          /* (4) adj state up */
+          isis_adj_state_change (adj, ISIS_ADJ_UP, NULL);
+          /* (5) adj usage level 1 */
+          adj->adj_usage = ISIS_ADJ_LEVEL1;
+        } else if (adj->adj_usage == ISIS_ADJ_LEVEL1) {
+          ; /* accept */
+        }
+        break;
+      case IS_LEVEL_2:
+        if (adj->adj_state != ISIS_ADJ_UP) {
+          /* (7) reject - wrong system type event */
+          zlog_warn ("wrongSystemType");
+          return ISIS_WARNING; /* Reject */
+        } else if (adj->adj_usage == ISIS_ADJ_LEVEL1) {
+          /* (6) down - wrong system */
+          isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System");
+        }
+        break;
+      }
+    }
+
+    /* 8.2.5.2 a) 3) If the system is L1L2 - table 6 */
+    if (circuit->area->is_type == IS_LEVEL_1_AND_2) {
+      switch (hdr->circuit_t) {
+      case IS_LEVEL_1:
+        if (adj->adj_state != ISIS_ADJ_UP) {
+          /* (6) adj state up */
+          isis_adj_state_change (adj, ISIS_ADJ_UP, NULL);
+          /* (7) adj usage level 1 */
+          adj->adj_usage = ISIS_ADJ_LEVEL1;
+        } else if (adj->adj_usage == ISIS_ADJ_LEVEL1) {
+          ; /* accept */
+        } else if ((adj->adj_usage == ISIS_ADJ_LEVEL1AND2) ||
+                   (adj->adj_usage == ISIS_ADJ_LEVEL2)) {
+          /* (8) down - wrong system */
+          isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System");
+        }
+        break;
+      case IS_LEVEL_2:
+        if (adj->adj_state != ISIS_ADJ_UP) {
+          /* (6) adj state up */
+          isis_adj_state_change (adj, ISIS_ADJ_UP, NULL);
+          /* (9) adj usage level 2 */
+          adj->adj_usage = ISIS_ADJ_LEVEL2;
+        } else if ((adj->adj_usage == ISIS_ADJ_LEVEL1) ||
+                   (adj->adj_usage == ISIS_ADJ_LEVEL1AND2)) {
+          /* (8) down - wrong system */
+          isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System");
+        } else if (adj->adj_usage == ISIS_ADJ_LEVEL2) {
+          ; /* Accept */
+        }
+        break;
+      case IS_LEVEL_1_AND_2:
+        if (adj->adj_state != ISIS_ADJ_UP) {
+          /* (6) adj state up */
+          isis_adj_state_change (adj, ISIS_ADJ_UP, NULL);
+          /* (10) adj usage level 1 */
+          adj->adj_usage = ISIS_ADJ_LEVEL1AND2;
+        } else if ((adj->adj_usage == ISIS_ADJ_LEVEL1) ||
+                   (adj->adj_usage == ISIS_ADJ_LEVEL2)) {
+          /* (8) down - wrong system */
+          isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System");
+        } else if (adj->adj_usage == ISIS_ADJ_LEVEL1AND2) {
+          ; /* Accept */
+        }
+        break;
+      }
+    }
+
+    /* 8.2.5.2 a) 4) If the system is L2 - table 7 */
+    if (circuit->area->is_type == IS_LEVEL_2) {
+      switch (hdr->circuit_t) {
+      case IS_LEVEL_1:
+        if (adj->adj_state != ISIS_ADJ_UP) {
+          /* (5) reject - wrong system type event */
+          zlog_warn ("wrongSystemType");
+          return ISIS_WARNING; /* Reject */
+        } else if ((adj->adj_usage == ISIS_ADJ_LEVEL1AND2) ||
+                   (adj->adj_usage == ISIS_ADJ_LEVEL2)) {
+          /* (6) down - wrong system */
+          isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System");
+        }
+        break;
+      case IS_LEVEL_1_AND_2:
+      case IS_LEVEL_2:
+        if (adj->adj_state != ISIS_ADJ_UP) {
+          /* (7) adj state up */
+          isis_adj_state_change (adj, ISIS_ADJ_UP, NULL);
+          /* (8) adj usage level 2 */
+          adj->adj_usage = ISIS_ADJ_LEVEL2;
+        } else if (adj->adj_usage == ISIS_ADJ_LEVEL1AND2) {
+          /* (6) down - wrong system */
+          isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System");
+        } else if (adj->adj_usage == ISIS_ADJ_LEVEL2) {
+          ; /* Accept */
+        }
+        break;
+      }
+    }
+  }
+  /* 8.2.5.2 b) if no match was detected */
+  else
+  {
+    if (circuit->area->is_type == IS_LEVEL_1) {
+      /* 8.2.5.2 b) 1) is_type L1 and adj is not up */
+      if (adj->adj_state != ISIS_ADJ_UP) {
+        isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Area Mismatch");
+      /* 8.2.5.2 b) 2)is_type L1 and adj is up */
+      } else {
+        isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Down - Area Mismatch");
+      }
+    }
+    /* 8.2.5.2 b 3 If the system is L2 or L1L2 - table 8 */
+    else
+    {
+      switch (hdr->circuit_t) {
+      case IS_LEVEL_1:
+        if (adj->adj_state != ISIS_ADJ_UP) {
+          /* (6) reject - Area Mismatch event */
+          zlog_warn ("AreaMismatch");
+          return ISIS_WARNING; /* Reject */
+        } else if (adj->adj_usage == ISIS_ADJ_LEVEL1) {
+          /* (7) down - area mismatch */
+          isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Area Mismatch");
+
+        } else if ((adj->adj_usage == ISIS_ADJ_LEVEL1AND2) ||
+                   (adj->adj_usage == ISIS_ADJ_LEVEL2)) {
+          /* (7) down - wrong system */
+          isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System");
+        }
+        break;
+      case IS_LEVEL_1_AND_2:
+      case IS_LEVEL_2:
+        if (adj->adj_state != ISIS_ADJ_UP) {
+          /* (8) adj state up */
+          isis_adj_state_change (adj, ISIS_ADJ_UP, NULL);
+          /* (9) adj usage level 2 */
+          adj->adj_usage = ISIS_ADJ_LEVEL2;
+        } else if (adj->adj_usage == ISIS_ADJ_LEVEL1) {
+          /* (7) down - wrong system */
+          isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System");
+        } else if (adj->adj_usage == ISIS_ADJ_LEVEL1AND2) {
+          if (hdr->circuit_t == IS_LEVEL_2) {
+            /* (7) down - wrong system */
+            isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System");
+          } else {
+            /* (7) down - area mismatch */
+            isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Area Mismatch");
+          }
+        } else if (adj->adj_usage == ISIS_ADJ_LEVEL2) {
+          ; /* Accept */
+        }
+        break;
+      }
+    }
+  }
+  /* 8.2.5.2 c) if the action was up - comparing circuit IDs */
+  /* FIXME - Missing parts */
+
+
+  /* some of my own understanding of the ISO, why the heck does
+   * it not say what should I change the system_type to...
+   */
+  switch (adj->adj_usage) {
+    case ISIS_ADJ_LEVEL1:
+      adj->sys_type = ISIS_SYSTYPE_L1_IS;
+      break;
+    case ISIS_ADJ_LEVEL2:
+      adj->sys_type = ISIS_SYSTYPE_L2_IS;
+      break;
+    case ISIS_ADJ_LEVEL1AND2:
+      adj->sys_type = ISIS_SYSTYPE_L2_IS;
+      break;
+    case ISIS_ADJ_NONE:
+      adj->sys_type = ISIS_SYSTYPE_UNKNOWN;
+      break;
+  }
+
+  adj->circuit_t = hdr->circuit_t;
+  adj->level = hdr->circuit_t;
+
+  free_tlvs (&tlvs);
+
+  return retval;
+}
+
+
+/*
+ * Process IS-IS LAN Level 1/2 Hello PDU
+ */
+static int 
+process_lan_hello (int level, struct isis_circuit *circuit, u_char *ssnpa)
+{
+  int retval = ISIS_OK;
+  struct isis_lan_hello_hdr hdr;
+  struct isis_adjacency *adj;
+  u_int32_t expected = 0, found;
+  struct tlvs tlvs;
+  u_char *snpa;
+  struct listnode *node;
+
+  if ((stream_get_endp (circuit->rcv_stream) - 
+       stream_get_getp (circuit->rcv_stream)) < ISIS_LANHELLO_HDRLEN) {
+    zlog_warn ("Packet too short");
+    return ISIS_WARNING;
+  }
+
+  if (circuit->ext_domain) {
+    zlog_info ("level %d LAN Hello received over circuit with "
+	       "externalDomain = true", level);
+    return ISIS_WARNING;
+  }
+
+  if (!accept_level (level, circuit->circuit_is_type)) {
+    if (isis->debugs & DEBUG_ADJ_PACKETS) {
+      zlog_info ("ISIS-Adj (%s): Interface level mismatch, %s",
+                 circuit->area->area_tag, circuit->interface->name);
+    }
+    return ISIS_WARNING;
+  }
+
+#if 0
+  /* Cisco's debug message compatability */
+  if (!accept_level (level, circuit->area->is_type)) {
+    if (isis->debugs & DEBUG_ADJ_PACKETS) {
+      zlog_info ("ISIS-Adj (%s): is type mismatch",
+                 circuit->area->area_tag);
+    }
+    return ISIS_WARNING;
+  }
+#endif
+  /*
+   * Fill the header
+   */
+  hdr.circuit_t = stream_getc (circuit->rcv_stream);
+  stream_get (hdr.source_id, circuit->rcv_stream, ISIS_SYS_ID_LEN);
+  hdr.hold_time = stream_getw (circuit->rcv_stream);
+  hdr.pdu_len   = stream_getw (circuit->rcv_stream);
+  hdr.prio      = stream_getc (circuit->rcv_stream);
+  stream_get (hdr.lan_id, circuit->rcv_stream, ISIS_SYS_ID_LEN + 1);
+
+  if (hdr.circuit_t != IS_LEVEL_1 && hdr.circuit_t != IS_LEVEL_2 &&
+      hdr.circuit_t != IS_LEVEL_1_AND_2 ) {
+    zlog_warn ("Level %d LAN Hello with Circuit Type %d", level, 
+	       hdr.circuit_t);
+    return ISIS_ERROR;
+  }
+  /*
+   * Then get the tlvs
+   */
+  expected |= TLVFLAG_AUTH_INFO;
+  expected |= TLVFLAG_AREA_ADDRS;
+  expected |= TLVFLAG_LAN_NEIGHS;
+  expected |= TLVFLAG_NLPID;
+  expected |= TLVFLAG_IPV4_ADDR;
+  expected |= TLVFLAG_IPV6_ADDR;
+
+  retval = parse_tlvs (circuit->area->area_tag,
+                       STREAM_PNT (circuit->rcv_stream),
+                       hdr.pdu_len - ISIS_LANHELLO_HDRLEN - ISIS_FIXED_HDR_LEN,
+                       &expected,
+                       &found,
+                       &tlvs);
+
+  if (retval > ISIS_WARNING) {
+    zlog_warn ("parse_tlvs() failed");
+    goto out;
+  }
+
+  if (!(found & TLVFLAG_AREA_ADDRS)) {
+    zlog_warn ("No Area addresses TLV in Level %d LAN IS to IS hello", level);
+    retval = ISIS_WARNING;
+    goto out;
+  }
+
+  if (circuit->passwd.type) {
+    if (!(found & TLVFLAG_AUTH_INFO) || 
+	authentication_check (&circuit->passwd, &tlvs.auth_info)) {
+      isis_event_auth_failure (circuit->area->area_tag, 
+			       "LAN hello authentication failure", 
+        hdr.source_id);
+      retval = ISIS_WARNING;
+      goto out;
+    }
+  }
+
+  /*
+   * Accept the level 1 adjacency only if a match between local and
+   * remote area addresses is found
+   */
+  if (level == 1 && !area_match (circuit->area->area_addrs, tlvs.area_addrs)) {
+    if (isis->debugs & DEBUG_ADJ_PACKETS) {
+      zlog_info ("ISIS-Adj (%s): Area mismatch, level %d IIH on %s",
+                 circuit->area->area_tag, level,circuit->interface->name);
+    }
+    retval = ISIS_OK;
+    goto out;
+  }
+
+  /* 
+   * it's own IIH PDU - discard silently 
+   */ 
+  if (!memcmp (circuit->u.bc.snpa, ssnpa, ETH_ALEN)) {
+    zlog_info ("ISIS-Adj (%s): it's own IIH PDU - discarded", 
+	       circuit->area->area_tag);
+
+    retval = ISIS_OK;
+    goto out;
+  }
+
+  /*
+   * check if it's own interface ip match iih ip addrs
+   */
+  if (!(found & TLVFLAG_IPV4_ADDR) || !ip_match(circuit->ip_addrs, tlvs.ipv4_addrs)) {
+    zlog_info("ISIS-Adj: No usable IP interface addresses in LAN IIH from %s\n",
+   		circuit->interface->name);
+    retval = ISIS_WARNING;
+    goto out;
+  }
+
+
+  adj = isis_adj_lookup (hdr.source_id, circuit->u.bc.adjdb[level - 1]);
+  if (!adj) {
+    /*
+     * Do as in 8.4.2.5
+     */
+    adj = isis_new_adj (hdr.source_id, ssnpa, level, circuit);
+    if (adj == NULL)
+      retval = ISIS_ERROR;
+      goto out;
+
+    adj->level = level;
+    isis_adj_state_change(adj, ISIS_ADJ_INITIALIZING, NULL);
+
+    if (level == 1) {
+      adj->sys_type = ISIS_SYSTYPE_L1_IS;
+    } else {
+      adj->sys_type = ISIS_SYSTYPE_L2_IS;
+    }
+    list_delete_all_node (circuit->u.bc.lan_neighs[level - 1]);
+    isis_adj_build_neigh_list (circuit->u.bc.adjdb[level - 1],
+                               circuit->u.bc.lan_neighs[level - 1]); 
+  }
+
+  switch (level) {
+  case 1 :
+    if (memcmp(circuit->u.bc.l1_desig_is, hdr.lan_id, ISIS_SYS_ID_LEN + 1)) {
+      thread_add_event (master, isis_event_dis_status_change, circuit, 0);
+      memcpy (&circuit->u.bc.l1_desig_is, hdr.lan_id, ISIS_SYS_ID_LEN + 1);
+    }
+    break;
+  case 2 : 
+    if (memcmp (circuit->u.bc.l2_desig_is, hdr.lan_id, ISIS_SYS_ID_LEN + 1)) {
+      thread_add_event (master, isis_event_dis_status_change, circuit, 0);
+      memcpy (&circuit->u.bc.l2_desig_is, hdr.lan_id, ISIS_SYS_ID_LEN + 1);
+    }
+    break;
+  }
+
+#if 0
+ /* Old solution: believe the lan-header always
+  */
+  if (level == 1) {
+    memcpy(circuit->u.bc.l1_desig_is, hdr.lan_id, ISIS_SYS_ID_LEN + 1);
+  } else if (level == 2) {
+    memcpy(circuit->u.bc.l2_desig_is, hdr.lan_id, ISIS_SYS_ID_LEN + 1);
+  }
+#endif
+
+  adj->hold_time = hdr.hold_time;
+  adj->last_upd  = time (NULL);
+  adj->prio[level-1] = hdr.prio;
+
+  memcpy (adj->lanid, hdr.lan_id, ISIS_SYS_ID_LEN + 1);
+
+  /* which protocol are spoken ??? */
+  if (found & TLVFLAG_NLPID) 
+    tlvs_to_adj_nlpids (&tlvs, adj);
+
+  /* we need to copy addresses to the adj */
+  if (found & TLVFLAG_IPV4_ADDR) 
+    tlvs_to_adj_ipv4_addrs (&tlvs, adj);
+
+#ifdef HAVE_IPV6
+  if (found & TLVFLAG_IPV6_ADDR) 
+    tlvs_to_adj_ipv6_addrs (&tlvs, adj);
+#endif /* HAVE_IPV6 */
+
+  adj->circuit_t = hdr.circuit_t;
+
+  /* lets take care of the expiry */
+  if (adj->t_expire) {
+    thread_cancel (adj->t_expire);
+  }
+  adj->t_expire = thread_add_timer (master, isis_adj_expire, adj,
+                                    (long)adj->hold_time);
+
+  /*
+   * If the snpa for this circuit is found from LAN Neighbours TLV
+   * we have two-way communication -> adjacency can be put to state "up"
+   */
+
+  if (found & TLVFLAG_LAN_NEIGHS) {
+    if (adj->adj_state != ISIS_ADJ_UP) {
+      LIST_LOOP (tlvs.lan_neighs, snpa, node)
+        if (!memcmp (snpa, circuit->u.bc.snpa, ETH_ALEN)) {
+          isis_adj_state_change (adj, ISIS_ADJ_UP, 
+                                 "own SNPA found in LAN Neighbours TLV");
+        }
+    }
+  }
+
+ out:
+  /* DEBUG_ADJ_PACKETS */
+  if (isis->debugs & DEBUG_ADJ_PACKETS) {
+    /* FIXME: is this place right? fix missing info */
+    zlog_info ("ISIS-Adj (%s): Rcvd L%d LAN IIH from %s on %s, cirType %s, "
+               "cirID %u, length %ld",
+	       circuit->area->area_tag, 
+               level,snpa_print(ssnpa), circuit->interface->name,
+               circuit_t2string(circuit->circuit_is_type),
+               circuit->circuit_id,
+               stream_get_endp (circuit->rcv_stream));
+  }
+
+
+  free_tlvs (&tlvs);
+
+  return retval;
+}
+
+/*
+ * Process Level 1/2 Link State
+ * ISO - 10589
+ * Section 7.3.15.1 - Action on receipt of a link state PDU
+ */ 
+static int 
+process_lsp (int level, struct isis_circuit *circuit, u_char *ssnpa)
+{
+  struct isis_link_state_hdr *hdr;
+  struct isis_adjacency *adj = NULL;
+  struct isis_lsp *lsp, *lsp0 = NULL;
+  int retval = ISIS_OK, comp = 0;
+  u_char lspid[ISIS_SYS_ID_LEN + 2];
+  struct isis_passwd *passwd;
+
+  /* Sanity check - FIXME: move to correct place */
+  if ((stream_get_endp (circuit->rcv_stream) - 
+       stream_get_getp (circuit->rcv_stream)) < ISIS_LSP_HDR_LEN ) {
+    zlog_warn ("Packet too short");
+    return ISIS_WARNING;
+  }
+
+  /* Reference the header   */
+  hdr = (struct isis_link_state_hdr*)STREAM_PNT (circuit->rcv_stream);
+
+  if (isis->debugs & DEBUG_UPDATE_PACKETS) {
+    zlog_info ("ISIS-Upd (%s): Rcvd L%d LSP %s, seq 0x%08x, cksum 0x%04x, "
+               "lifetime %us, len %lu, on %s",
+	       circuit->area->area_tag,
+	       level, 
+               rawlspid_print(hdr->lsp_id),
+	       ntohl(hdr->seq_num),
+	       ntohs(hdr->checksum),
+	       ntohs(hdr->rem_lifetime),
+	       circuit->rcv_stream->endp,
+               circuit->interface->name);
+  }
+
+  assert (ntohs (hdr->pdu_len) > ISIS_LSP_HDR_LEN);
+
+  /* Checksum sanity check - FIXME: move to correct place */
+  /* 12 = sysid+pdu+remtime */
+  if (iso_csum_verify (STREAM_PNT (circuit->rcv_stream) + 4, 
+      ntohs (hdr->pdu_len) - 12, &hdr->checksum)) {
+    zlog_info ("ISIS-Upd (%s): LSP %s invalid LSP checksum 0x%04x",
+	       circuit->area->area_tag,
+	       rawlspid_print (hdr->lsp_id),
+	       ntohs(hdr->checksum));
+
+    return ISIS_WARNING;
+  }
+
+  /* 7.3.15.1 a) 1 - external domain circuit will discard lsps */
+  if (circuit->ext_domain) {
+    zlog_info ("ISIS-Upd (%s): LSP %s received at level %d over circuit with "
+               "externalDomain = true",
+	       circuit->area->area_tag,
+	       rawlspid_print (hdr->lsp_id),	       
+	       level);
+
+    return ISIS_WARNING;
+  }
+
+  /* 7.3.15.1 a) 2,3 - manualL2OnlyMode not implemented */
+  if (!accept_level (level, circuit->circuit_is_type)) {
+    zlog_info ("ISIS-Upd (%s): LSP %s received at level %d over circuit of"
+               " type %s", 
+	       circuit->area->area_tag,
+	       rawlspid_print(hdr->lsp_id),	
+               level,
+	       circuit_t2string (circuit->circuit_is_type));
+
+    return ISIS_WARNING;
+  }
+
+  /* 7.3.15.1 a) 4 - need to make sure IDLength matches */
+
+  /* 7.3.15.1 a) 5 - maximum area match, can be ommited since we only use 3 */
+
+  /* 7.3.15.1 a) 7 - password check */
+  (level == ISIS_LEVEL1) ? (passwd = &circuit->area->area_passwd) :
+    (passwd = &circuit->area->domain_passwd);
+  if (passwd->type) {
+    if (isis_lsp_authinfo_check (circuit->rcv_stream, circuit->area,
+				 ntohs (hdr->pdu_len), passwd)) {
+      isis_event_auth_failure (circuit->area->area_tag,
+			       "LSP authentication failure",
+			       hdr->lsp_id);
+      return ISIS_WARNING;
+    }
+  }
+  /* Find the LSP in our database and compare it to this Link State header */
+  lsp = lsp_search (hdr->lsp_id, circuit->area->lspdb[level - 1]);
+  if (lsp)
+    comp = lsp_compare (circuit->area->area_tag, lsp, hdr->seq_num, 
+                        hdr->checksum, hdr->rem_lifetime);
+  if (lsp && (lsp->own_lsp 
+#ifdef TOPOLOGY_GENERATE
+              || lsp->from_topology
+#endif /* TOPOLOGY_GENERATE */
+              ))
+    goto dontcheckadj;
+
+  /* 7.3.15.1 a) 6 - Must check that we have an adjacency of the same level  */
+  /* for broadcast circuits, snpa should be compared */
+  /* FIXME : Point To Point */
+
+  if (circuit->circ_type == CIRCUIT_T_BROADCAST) {
+    adj = isis_adj_lookup_snpa (ssnpa, circuit->u.bc.adjdb[level - 1]);
+    if (!adj) {
+      zlog_info ("(%s): DS ======= LSP %s, seq 0x%08x, cksum 0x%04x, "
+		 "lifetime %us on %s",
+		 circuit->area->area_tag,
+		 rawlspid_print (hdr->lsp_id),
+		 ntohl (hdr->seq_num),
+		 ntohs (hdr->checksum),
+		 ntohs (hdr->rem_lifetime), 
+		 circuit->interface->name);
+      return ISIS_WARNING; /* Silently discard */
+    }
+  }
+
+  /* for non broadcast, we just need to find same level adj */
+  else {
+    /* If no adj, or no sharing of level */
+    if (!circuit->u.p2p.neighbor) {
+      return ISIS_OK; /* Silently discard */
+    } else {
+      if (((level == 1) && 
+           (circuit->u.p2p.neighbor->adj_usage == ISIS_ADJ_LEVEL2)) ||
+          ((level == 2) && 
+           (circuit->u.p2p.neighbor->adj_usage == ISIS_ADJ_LEVEL1)))
+      return ISIS_WARNING; /* Silently discard */
+    }
+  }
+ dontcheckadj:
+  /* 7.3.15.1 a) 7 - Passwords for level 1 - not implemented  */
+
+  /* 7.3.15.1 a) 8 - Passwords for level 2 - not implemented  */
+
+  /* 7.3.15.1 a) 9 - OriginatingLSPBufferSize - not implemented  FIXME: do it*/
+
+
+  /* 7.3.15.1 b) - If the remaining life time is 0, we perform 7.3.16.4*/
+  if (hdr->rem_lifetime == 0) {
+    if (!lsp) {
+      /* 7.3.16.4 a) 1) No LSP in db -> send an ack, but don't save */
+      /* only needed on explicit update, eg - p2p */
+      if (circuit->circ_type == CIRCUIT_T_P2P)
+        ack_lsp (hdr, circuit, level);
+      return retval; /* FIXME: do we need a purge? */
+    } else {
+      if (memcmp (hdr->lsp_id, isis->sysid, ISIS_SYS_ID_LEN )) {
+        /* LSP by some other system -> do 7.3.16.4 b) */
+        /* 7.3.16.4 b) 1)  */
+        if (comp == LSP_NEWER) {
+          lsp_update (lsp, hdr, circuit->rcv_stream, circuit->area);
+          /* ii */
+          ISIS_FLAGS_SET_ALL (lsp->SRMflags);   
+          /* iii */
+          ISIS_CLEAR_FLAG (lsp->SRMflags, circuit);
+          /* v */
+          ISIS_FLAGS_CLEAR_ALL(lsp->SSNflags); /* FIXME: OTHER than c */
+          /* iv */
+          if (circuit->circ_type != CIRCUIT_T_BROADCAST)
+            ISIS_SET_FLAG(lsp->SSNflags, circuit);
+
+        } /* 7.3.16.4 b) 2) */
+        else if (comp == LSP_EQUAL) {
+          /* i */
+          ISIS_CLEAR_FLAG(lsp->SRMflags, circuit);
+          /* ii*/
+          if (circuit->circ_type != CIRCUIT_T_BROADCAST)
+            ISIS_SET_FLAG(lsp->SSNflags, circuit);
+        }  /* 7.3.16.4 b) 3) */
+        else {
+          ISIS_SET_FLAG(lsp->SRMflags, circuit);
+          ISIS_CLEAR_FLAG(lsp->SSNflags, circuit);
+        }
+      } else {
+        /* our own LSP -> 7.3.16.4 c) */
+        if (LSP_PSEUDO_ID(lsp->lsp_header->lsp_id) != circuit->circuit_id ||
+            (LSP_PSEUDO_ID(lsp->lsp_header->lsp_id) == circuit->circuit_id &&
+             circuit->u.bc.is_dr[level - 1] == 1) ) { 
+          lsp->lsp_header->seq_num = htonl (ntohl (hdr->seq_num) + 1);
+          zlog_info ("LSP LEN: %d", ntohs (lsp->lsp_header->pdu_len));
+          iso_csum_create (STREAM_DATA (lsp->pdu) + 12, 
+                           ntohs (lsp->lsp_header->pdu_len) - 12, 12);
+          ISIS_FLAGS_SET_ALL (lsp->SRMflags);
+          zlog_info ("ISIS-Upd (%s): (1) re-originating LSP %s new seq 0x%08x",
+                     circuit->area->area_tag,
+                     rawlspid_print (hdr->lsp_id),
+                     ntohl (lsp->lsp_header->seq_num));
+          lsp->lsp_header->rem_lifetime = htons (isis_jitter 
+                                                 (circuit->area->
+                                                  max_lsp_lifetime[level-1],
+                                                  MAX_AGE_JITTER));
+
+        } else {
+          /* Got purge for own pseudo-lsp, and we are not DR  */
+            lsp_purge_dr (lsp->lsp_header->lsp_id, circuit, level);
+        } 
+      }
+    }
+    return retval;
+  }
+  /* 7.3.15.1 c) - If this is our own lsp and we don't have it initiate a 
+   * purge */
+  if (memcmp (hdr->lsp_id, isis->sysid, ISIS_SYS_ID_LEN ) == 0) {
+    if (!lsp) {
+    /* 7.3.16.4: initiate a purge */
+      lsp_purge_non_exist (hdr, circuit->area);
+      return ISIS_OK;
+    }
+    /* 7.3.15.1 d) - If this is our own lsp and we have it */
+
+    /* In 7.3.16.1, If an Intermediate system R somewhere in the domain
+     * has information that the current sequence number for source S is
+     * "greater" than that held by S, ... */
+
+    else if (ntohl (hdr->seq_num) > ntohl (lsp->lsp_header->seq_num)) {
+      /* 7.3.16.1  */
+      lsp->lsp_header->seq_num = htonl (ntohl (hdr->seq_num) + 1);
+
+      iso_csum_create (STREAM_DATA (lsp->pdu) + 12, 
+                       ntohs(lsp->lsp_header->pdu_len) - 12, 12);
+
+      ISIS_FLAGS_SET_ALL (lsp->SRMflags);
+      zlog_info ("ISIS-Upd (%s): (2) re-originating LSP %s new seq 0x%08x",
+                 circuit->area->area_tag,
+                 rawlspid_print (hdr->lsp_id),
+                 ntohl (lsp->lsp_header->seq_num));
+      lsp->lsp_header->rem_lifetime = htons (isis_jitter 
+                                             (circuit->
+                                              area->max_lsp_lifetime[level-1],
+                                              MAX_AGE_JITTER));
+
+    }
+  } else {
+  /* 7.3.15.1 e) - This lsp originated on another system */
+
+    /* 7.3.15.1 e) 1) LSP newer than the one in db or no LSP in db */
+    if ((!lsp || comp == LSP_NEWER)){
+      /* i */
+      if (lsp) {
+#ifdef EXTREME_DEBUG
+        zlog_info ("level %d number is - %ld", level, 
+                   circuit->area->lspdb[level-1]->dict_nodecount);
+#endif /* EXTREME DEBUG */
+        lsp_search_and_destroy (hdr->lsp_id, circuit->area->lspdb[level-1]);
+        /* exists, so we overwrite */
+#ifdef EXTREME_DEBUG
+        zlog_info ("level %d number is - %ld",level, 
+                   circuit->area->lspdb[level-1]->dict_nodecount);
+#endif /* EXTREME DEBUG */
+      }
+      /*
+       * If this lsp is a frag, need to see if we have zero lsp present
+       */
+      if (LSP_FRAGMENT (hdr->lsp_id) != 0) {
+        memcpy (lspid, hdr->lsp_id, ISIS_SYS_ID_LEN + 1);
+        LSP_FRAGMENT (lspid) = 0;
+        lsp0 = lsp_search (lspid, circuit->area->lspdb[level - 1]);
+        if (!lsp0) {
+          zlog_info ("Got lsp frag, while zero lsp not database");
+          return ISIS_OK;
+        }
+      }
+      lsp = lsp_new_from_stream_ptr (circuit->rcv_stream, ntohs (hdr->pdu_len),
+                                     lsp0, circuit->area);
+      lsp->level = level;
+      lsp->adj = adj;
+      lsp_insert (lsp, circuit->area->lspdb[level-1]);
+      /* ii */
+      ISIS_FLAGS_SET_ALL (lsp->SRMflags);
+      /* iii */
+      ISIS_CLEAR_FLAG (lsp->SRMflags, circuit);
+
+      /* iv */
+      if (circuit->circ_type != CIRCUIT_T_BROADCAST)
+        ISIS_SET_FLAG (lsp->SSNflags, circuit);
+      /* FIXME: v) */
+    }
+    /* 7.3.15.1 e) 2) LSP equal to the one in db */
+    else if (comp == LSP_EQUAL) {
+      ISIS_CLEAR_FLAG (lsp->SRMflags, circuit);
+      lsp_update (lsp, hdr, circuit->rcv_stream, circuit->area);
+      if (circuit->circ_type != CIRCUIT_T_BROADCAST) {
+        ISIS_SET_FLAG (lsp->SSNflags, circuit);
+      }
+    }
+    /* 7.3.15.1 e) 3) LSP older than the one in db */
+    else {
+      ISIS_SET_FLAG(lsp->SRMflags, circuit);
+      ISIS_CLEAR_FLAG(lsp->SSNflags, circuit);
+    }
+  }
+  if (lsp)
+    lsp->adj = adj;
+  return retval;
+}
+
+/*
+ * Process Sequence Numbers
+ * ISO - 10589
+ * Section 7.3.15.2 - Action on receipt of a sequence numbers PDU
+ */
+
+int
+process_snp (int snp_type, int level, struct isis_circuit *circuit, 
+             u_char *ssnpa)
+{
+  int retval = ISIS_OK;
+  int cmp, own_lsp;
+  char typechar = ' ';
+  int len;
+  struct isis_adjacency *adj;
+  struct isis_complete_seqnum_hdr *chdr = NULL;
+  struct isis_partial_seqnum_hdr *phdr = NULL;
+  uint32_t found = 0, expected = 0;
+  struct isis_lsp *lsp;
+  struct lsp_entry *entry;
+  struct listnode *node,*node2;
+  struct tlvs tlvs;
+  struct list *lsp_list = NULL;
+  struct isis_passwd *passwd;
+
+  if (snp_type == ISIS_SNP_CSNP_FLAG) {
+  /* getting the header info */
+    typechar = 'C';
+    chdr = (struct isis_complete_seqnum_hdr*)STREAM_PNT(circuit->rcv_stream);
+    circuit->rcv_stream->getp += ISIS_CSNP_HDRLEN;
+    len = ntohs(chdr->pdu_len);
+    if (len < ISIS_CSNP_HDRLEN) {
+      zlog_warn ("Received a CSNP with bogus length!");
+      return ISIS_OK;
+    }
+  } else {
+    typechar = 'P';
+    phdr = (struct isis_partial_seqnum_hdr*)STREAM_PNT(circuit->rcv_stream);
+    circuit->rcv_stream->getp += ISIS_PSNP_HDRLEN;
+    len = ntohs(phdr->pdu_len);
+    if (len < ISIS_PSNP_HDRLEN) {
+      zlog_warn ("Received a CSNP with bogus length!");
+      return ISIS_OK;
+    }
+  }
+
+  /* 7.3.15.2 a) 1 - external domain circuit will discard snp pdu */
+  if (circuit->ext_domain) {
+
+    zlog_info ("ISIS-Snp (%s): Rcvd L%d %cSNP on %s, "
+	       "skipping: circuit externalDomain = true",
+	       circuit->area->area_tag,
+	       level,
+	       typechar,
+	       circuit->interface->name);
+
+    return ISIS_OK;
+  }
+
+  /* 7.3.15.2 a) 2,3 - manualL2OnlyMode not implemented */
+  if (!accept_level (level, circuit->circuit_is_type)) {
+
+    zlog_info ("ISIS-Snp (%s): Rcvd L%d %cSNP on %s, "
+	       "skipping: circuit type %s does not match level %d",
+	       circuit->area->area_tag,
+	       level, 
+               typechar,
+	       circuit->interface->name,
+	       circuit_t2string (circuit->circuit_is_type),
+	       level);
+
+    return ISIS_OK;
+  }
+
+  /* 7.3.15.2 a) 4 - not applicable for CSNP  only PSNPs on broadcast */
+  if ((snp_type == ISIS_SNP_PSNP_FLAG) && 
+      (circuit->circ_type == CIRCUIT_T_BROADCAST)) {
+    if (!circuit->u.bc.is_dr[level-1]) {
+
+      zlog_info ("ISIS-Snp (%s): Rcvd L%d %cSNP from %s on %s, "
+		 "skipping: we are not the DIS",
+		 circuit->area->area_tag,
+                 level,
+		 typechar,
+		 snpa_print(ssnpa),
+		 circuit->interface->name);
+
+      return ISIS_OK;
+    }
+  }
+
+  /* 7.3.15.2 a) 5 - need to make sure IDLength matches - already checked */
+
+  /* 7.3.15.2 a) 6 - maximum area match, can be ommited since we only use 3
+   * - already checked */
+
+  /* 7.3.15.2 a) 7 - Must check that we have an adjacency of the same level  */
+  /* for broadcast circuits, snpa should be compared */
+  /* FIXME : Do we need to check SNPA? */
+  if (circuit->circ_type == CIRCUIT_T_BROADCAST) {
+    if (snp_type == ISIS_SNP_CSNP_FLAG) {
+      adj = isis_adj_lookup (chdr->source_id, circuit->u.bc.adjdb[level - 1]);
+    } else {
+      /* a psnp on a broadcast, how lovely of Juniper :) */
+      adj = isis_adj_lookup (phdr->source_id, circuit->u.bc.adjdb[level - 1]);
+    }
+    if (!adj)
+      return ISIS_OK; /* Silently discard */
+  } else {
+    if (!circuit->u.p2p.neighbor)
+      return ISIS_OK; /* Silently discard */
+  }
+
+  /* 7.3.15.2 a) 8 - Passwords for level 1 - not implemented  */
+
+  /* 7.3.15.2 a) 9 - Passwords for level 2 - not implemented  */
+
+  memset (&tlvs, 0, sizeof (struct tlvs));
+
+  /* parse the SNP */
+  expected |= TLVFLAG_LSP_ENTRIES;
+  expected |= TLVFLAG_AUTH_INFO;
+  retval = parse_tlvs (circuit->area->area_tag,
+		       STREAM_PNT(circuit->rcv_stream),
+		       len - circuit->rcv_stream->getp,
+		       &expected,
+		       &found,
+		       &tlvs);
+
+  if (retval > ISIS_WARNING) {
+    zlog_warn ("something went very wrong processing SNP");
+    free_tlvs (&tlvs);
+    return retval;
+  }
+
+  (level == 1) ? (passwd = &circuit->area->area_passwd) :
+		  (passwd = &circuit->area->domain_passwd);
+  if (passwd->type) {
+    if (!(found & TLVFLAG_AUTH_INFO) ||
+	authentication_check (passwd, &tlvs.auth_info)) {
+      isis_event_auth_failure (circuit->area->area_tag, "SNP authentication"
+			       " failure", phdr ?
+			       phdr->source_id : chdr->source_id);
+      return ISIS_OK;
+    } 
+  }
+
+  /* debug isis snp-packets */
+  if (isis->debugs & DEBUG_SNP_PACKETS) {
+    zlog_info ("ISIS-Snp (%s): Rcvd L%d %cSNP from %s on %s", 
+               circuit->area->area_tag,
+	       level,
+	       typechar,
+	       snpa_print(ssnpa),
+               circuit->interface->name);
+    if (tlvs.lsp_entries) {
+      LIST_LOOP (tlvs.lsp_entries,entry,node) {
+        zlog_info("ISIS-Snp (%s):         %cSNP entry %s, seq 0x%08x,"
+                  " cksum 0x%04x, lifetime %us", 
+                  circuit->area->area_tag,
+                  typechar, 
+                  rawlspid_print (entry->lsp_id),
+                  ntohl (entry->seq_num),
+                  ntohs (entry->checksum),
+                  ntohs (entry->rem_lifetime));
+      }
+    }
+  }
+
+  /* 7.3.15.2 b) Actions on LSP_ENTRIES reported */
+  if (tlvs.lsp_entries) {
+    LIST_LOOP (tlvs.lsp_entries, entry, node) {
+      lsp = lsp_search (entry->lsp_id, circuit->area->lspdb[level - 1]);
+      own_lsp = !memcmp (entry->lsp_id, isis->sysid, ISIS_SYS_ID_LEN);
+      if (lsp) {
+        /* 7.3.15.2 b) 1) is this LSP newer */
+        cmp = lsp_compare (circuit->area->area_tag, lsp, entry->seq_num, 
+                           entry->checksum, entry->rem_lifetime);
+        /* 7.3.15.2 b) 2) if it equals, clear SRM on p2p */
+        if (cmp == LSP_EQUAL) {
+          if (circuit->circ_type != CIRCUIT_T_BROADCAST) 
+            ISIS_CLEAR_FLAG (lsp->SRMflags, circuit);
+          /* 7.3.15.2 b) 3) if it is older, clear SSN and set SRM */
+        } else if (cmp == LSP_OLDER) {
+          ISIS_CLEAR_FLAG (lsp->SSNflags, circuit);
+        ISIS_SET_FLAG (lsp->SRMflags, circuit);
+        } else {
+          /* 7.3.15.2 b) 4) if it is newer, set SSN and clear SRM on p2p*/
+          if (own_lsp) {
+            lsp_inc_seqnum (lsp, ntohl (entry->seq_num));
+            ISIS_SET_FLAG (lsp->SRMflags, circuit);
+          } else {
+            ISIS_SET_FLAG (lsp->SSNflags, circuit);
+            if (circuit->circ_type != CIRCUIT_T_BROADCAST)
+            ISIS_CLEAR_FLAG (lsp->SRMflags, circuit); 
+          }
+        }
+      } else {
+        /* 7.3.15.2 b) 5) if it was not found, and all of those are not 0, 
+         * insert it and set SSN on it */
+        if (entry->rem_lifetime && entry->checksum && entry->seq_num && 
+            memcmp (entry->lsp_id, isis->sysid, ISIS_SYS_ID_LEN)) {
+          lsp = lsp_new (entry->lsp_id, ntohs (entry->rem_lifetime),
+                       0, 0, entry->checksum, level);
+          lsp_insert (lsp, circuit->area->lspdb[level - 1]);
+          ISIS_SET_FLAG (lsp->SSNflags, circuit);
+        }
+      }
+    }
+  }
+
+  /* 7.3.15.2 c) on CSNP set SRM for all in range which were not reported */
+  if (snp_type == ISIS_SNP_CSNP_FLAG) {
+    /*
+     * Build a list from our own LSP db bounded with start_ and stop_lsp_id
+     */
+    lsp_list = list_new ();
+    lsp_build_list_nonzero_ht (chdr->start_lsp_id, chdr->stop_lsp_id, 
+                               lsp_list, circuit->area->lspdb[level - 1]);
+
+    /* Fixme: Find a better solution */
+    if (tlvs.lsp_entries) {
+      LIST_LOOP (tlvs.lsp_entries, entry, node) {
+        LIST_LOOP (lsp_list, lsp, node2) {
+          if (lsp_id_cmp (lsp->lsp_header->lsp_id, entry->lsp_id) == 0) {
+            list_delete_node (lsp_list, node2);
+          break;
+          }
+        }
+      }
+    }
+    /* on remaining LSPs we set SRM (neighbor knew not of) */
+    LIST_LOOP (lsp_list, lsp, node2) {
+      ISIS_SET_FLAG (lsp->SRMflags, circuit);
+    }
+    /* lets free it */
+    list_free (lsp_list);
+  }
+
+  free_tlvs (&tlvs);
+  return retval;
+}
+
+int
+process_csnp (int level, struct isis_circuit *circuit, u_char *ssnpa)
+{
+
+  /* Sanity check - FIXME: move to correct place */
+  if ((stream_get_endp (circuit->rcv_stream) - 
+       stream_get_getp (circuit->rcv_stream)) < ISIS_CSNP_HDRLEN) {
+    zlog_warn ("Packet too short ( < %d)",  ISIS_CSNP_HDRLEN);
+    return ISIS_WARNING;
+  }
+
+  return process_snp (ISIS_SNP_CSNP_FLAG, level, circuit, ssnpa);
+}
+
+int 
+process_psnp (int level, struct isis_circuit *circuit, u_char *ssnpa)
+{
+
+  if ((stream_get_endp (circuit->rcv_stream) - 
+       stream_get_getp (circuit->rcv_stream)) < ISIS_PSNP_HDRLEN) {
+    zlog_warn ("Packet too short");
+    return ISIS_WARNING;
+  }
+
+  return process_snp (ISIS_SNP_PSNP_FLAG, level, circuit, ssnpa);
+}
+
+
+
+/*
+ * Process ISH
+ * ISO - 10589
+ * Section 8.2.2 - Receiving ISH PDUs by an intermediate system
+ * FIXME: sample packet dump, need to figure 0x81 - looks like NLPid
+            0x82	0x15	0x01	0x00	0x04	0x01	0x2c	0x59
+            0x38	0x08	0x47	0x00	0x01	0x00	0x02	0x00
+          	0x03	0x00	0x81	0x01	0xcc
+ */
+int
+process_is_hello (struct isis_circuit *circuit)
+{
+  struct isis_adjacency *adj;
+  int retval = ISIS_OK;
+  u_char neigh_len;
+  u_char *sysid;
+
+  /* In this point in time we are not yet able to handle is_hellos
+   * on lan - Sorry juniper...
+   */
+  if (circuit->circ_type == CIRCUIT_T_BROADCAST)
+    return retval;
+
+  neigh_len = stream_getc (circuit->rcv_stream);
+  sysid = STREAM_PNT(circuit->rcv_stream) + neigh_len - 1 - ISIS_SYS_ID_LEN;
+  adj = circuit->u.p2p.neighbor;
+  if (!adj) {
+    /* 8.2.2 */
+    adj = isis_new_adj (sysid, "      ", 0, circuit);
+    if (adj == NULL)
+      return ISIS_ERROR;
+
+    isis_adj_state_change (adj, ISIS_ADJ_INITIALIZING, NULL);
+    adj->sys_type = ISIS_SYSTYPE_UNKNOWN;
+    circuit->u.p2p.neighbor = adj;
+  }
+  /* 8.2.2 a)*/
+  if ((adj->adj_state == ISIS_ADJ_UP) && memcmp (adj->sysid,sysid,
+                                                 ISIS_SYS_ID_LEN)) {
+    /* 8.2.2 a) 1) FIXME: adjStateChange(down) event */
+    /* 8.2.2 a) 2) delete the adj */
+    XFREE (MTYPE_ISIS_ADJACENCY, adj);
+    /* 8.2.2 a) 3) create a new adj */
+    adj = isis_new_adj (sysid, "      ", 0, circuit);
+    if (adj == NULL)
+      return ISIS_ERROR;
+
+    /* 8.2.2 a) 3) i */
+    isis_adj_state_change (adj, ISIS_ADJ_INITIALIZING, NULL);
+    /* 8.2.2 a) 3) ii */
+    adj->sys_type = ISIS_SYSTYPE_UNKNOWN;
+    /* 8.2.2 a) 4) quite meaningless */
+  }
+  /* 8.2.2 b) ignore on condition */
+  if ((adj->adj_state == ISIS_ADJ_INITIALIZING) && 
+      (adj->sys_type == ISIS_SYSTYPE_IS)) {
+    /* do nothing */
+  } else {
+  /* 8.2.2 c) respond with a p2p IIH */
+    send_hello (circuit, 1);
+  }
+  /* 8.2.2 d) type is IS */
+    adj->sys_type = ISIS_SYSTYPE_IS;
+  /* 8.2.2 e) FIXME: Circuit type of? */
+
+
+  return retval;
+}
+
+
+/*
+ * PDU Dispatcher
+ */
+
+int 
+isis_handle_pdu (struct isis_circuit *circuit, u_char *ssnpa)
+{
+
+  struct isis_fixed_hdr *hdr;
+  struct esis_fixed_hdr *esis_hdr;
+
+  int retval=ISIS_OK;
+
+  /*
+   * Let's first read data from stream to the header
+   */
+  hdr = (struct isis_fixed_hdr*)STREAM_DATA(circuit->rcv_stream);
+
+  if ((hdr->idrp != ISO10589_ISIS) && (hdr->idrp != ISO9542_ESIS)){
+    zlog_warn ("Not an IS-IS or ES-IS packet IDRP=%02x", hdr->idrp);
+    return ISIS_ERROR;
+  }
+
+  /* now we need to know if this is an ISO 9542 packet and
+   * take real good care of it, waaa!
+   */
+  if (hdr->idrp == ISO9542_ESIS){
+    esis_hdr = (struct esis_fixed_hdr*)STREAM_DATA(circuit->rcv_stream);
+    stream_set_getp (circuit->rcv_stream, ESIS_FIXED_HDR_LEN);
+    /* FIXME: Need to do some acceptence tests */
+    /* example length... */
+    switch (esis_hdr->pdu_type) {
+      case ESH_PDU:
+        /* FIXME */
+        break;
+      case ISH_PDU:
+        zlog_info ("AN ISH PDU!!");
+        retval = process_is_hello (circuit);
+        break;
+      default:
+        return ISIS_ERROR;
+      }
+    return retval;
+  } else {
+    stream_set_getp (circuit->rcv_stream, ISIS_FIXED_HDR_LEN);
+  }
+  /*
+   * and then process it
+   */
+
+  if (hdr->length < ISIS_MINIMUM_FIXED_HDR_LEN) {
+    zlog_err ("Fixed header length = %d", hdr->length);
+    return ISIS_ERROR;
+  }
+
+  if (hdr->version1 != 1) {
+    zlog_warn ("Unsupported ISIS version %u", hdr->version1);
+    return ISIS_WARNING;
+  }
+  /* either 6 or 0 */
+  if ((hdr->id_len != 0) && (hdr->id_len != ISIS_SYS_ID_LEN))  { 
+    zlog_err ("IDFieldLengthMismatch: ID Length field in a received PDU  %u, "
+                      "while the parameter for this IS is %u", hdr->id_len,
+                       ISIS_SYS_ID_LEN);
+    return ISIS_ERROR;
+  }
+
+  if (hdr->version2 != 1) {
+    zlog_warn ("Unsupported ISIS version %u", hdr->version2);
+    return ISIS_WARNING;
+  }
+  /* either 3 or 0 */
+  if ((hdr->max_area_addrs != 0) && (hdr->max_area_addrs != isis->max_area_addrs)) { 
+    zlog_err ("maximumAreaAddressesMismatch: maximumAreaAdresses in a "
+                      "received PDU %u while the parameter for this IS is %u",
+                       hdr->max_area_addrs, isis->max_area_addrs);
+    return ISIS_ERROR;
+  }
+
+  switch (hdr->pdu_type) {
+  case L1_LAN_HELLO:
+    retval = process_lan_hello (ISIS_LEVEL1, circuit, ssnpa);
+    break;
+  case L2_LAN_HELLO:
+    retval = process_lan_hello (ISIS_LEVEL2, circuit, ssnpa);
+    break;
+  case P2P_HELLO:
+    retval = process_p2p_hello (circuit);
+    break;
+  case L1_LINK_STATE:
+    retval = process_lsp (ISIS_LEVEL1, circuit, ssnpa);
+    break;
+  case L2_LINK_STATE:
+    retval = process_lsp (ISIS_LEVEL2, circuit, ssnpa);
+    break;
+  case L1_COMPLETE_SEQ_NUM:
+    retval = process_csnp (ISIS_LEVEL1, circuit, ssnpa);
+    break;
+  case L2_COMPLETE_SEQ_NUM:
+    retval = process_csnp (ISIS_LEVEL2, circuit, ssnpa);
+    break;
+  case L1_PARTIAL_SEQ_NUM:
+    retval = process_psnp (ISIS_LEVEL1, circuit, ssnpa);
+    break;
+  case L2_PARTIAL_SEQ_NUM:
+    retval = process_psnp (ISIS_LEVEL2, circuit, ssnpa);
+    break;
+  default:
+    return ISIS_ERROR;
+  }
+
+  return retval;
+}
+
+
+#ifdef GNU_LINUX
+int
+isis_receive (struct thread *thread)
+{
+
+  struct isis_circuit *circuit;
+  u_char ssnpa[ETH_ALEN];
+  int retval;
+
+  /*
+   * Get the circuit 
+   */
+  circuit = THREAD_ARG (thread);
+  assert (circuit);
+
+  if (circuit->rcv_stream == NULL)
+    circuit->rcv_stream = stream_new (ISO_MTU(circuit));
+  else
+    stream_reset (circuit->rcv_stream);
+
+  retval = circuit->rx (circuit, ssnpa);
+  circuit->t_read = NULL;  
+
+  if (retval == ISIS_OK)
+    retval = isis_handle_pdu (circuit, ssnpa);
+
+  /* 
+   * prepare for next packet. 
+   */
+  circuit->t_read = thread_add_read (master, isis_receive, circuit, 
+                                     circuit->fd);
+
+  return retval;
+}
+
+#else
+int
+isis_receive (struct thread *thread)
+{
+
+  struct isis_circuit *circuit;
+  u_char ssnpa[ETH_ALEN];
+  int retval;
+
+  /*
+   * Get the circuit 
+   */
+  circuit = THREAD_ARG (thread);
+  assert (circuit);
+
+  circuit->t_read = NULL;  
+
+  if (circuit->rcv_stream == NULL)
+    circuit->rcv_stream = stream_new (ISO_MTU(circuit));
+  else
+    stream_reset (circuit->rcv_stream);
+
+  retval = circuit->rx (circuit, ssnpa);
+
+  if (retval == ISIS_OK)
+    retval = isis_handle_pdu (circuit, ssnpa);
+
+  /* 
+   * prepare for next packet. 
+   */
+  circuit->t_read = thread_add_timer_msec (master, isis_receive, circuit, 
+                                           listcount
+                                           (circuit->area->circuit_list)*100);
+
+
+  return retval;
+}
+
+#endif
+
+ /* filling of the fixed isis header */
+void
+fill_fixed_hdr (struct isis_fixed_hdr *hdr, u_char pdu_type)
+{
+  memset (hdr, 0, sizeof (struct isis_fixed_hdr));
+
+  hdr->idrp = ISO10589_ISIS;
+
+  switch (pdu_type) {
+  case L1_LAN_HELLO:
+  case L2_LAN_HELLO:
+    hdr->length = ISIS_LANHELLO_HDRLEN;
+    break;
+  case P2P_HELLO:
+    hdr->length = ISIS_P2PHELLO_HDRLEN;
+    break;
+  case L1_LINK_STATE:
+  case L2_LINK_STATE:
+    hdr->length = ISIS_LSP_HDR_LEN;
+    break;
+  case L1_COMPLETE_SEQ_NUM:
+  case L2_COMPLETE_SEQ_NUM:
+    hdr->length = ISIS_CSNP_HDRLEN;
+    break;
+  case L1_PARTIAL_SEQ_NUM:
+  case L2_PARTIAL_SEQ_NUM:
+    hdr->length = ISIS_PSNP_HDRLEN;
+    break;
+  default:
+    zlog_warn ("fill_fixed_hdr(): unknown pdu type %d", pdu_type);
+    return;
+  }
+  hdr->length += ISIS_FIXED_HDR_LEN;
+  hdr->pdu_type = pdu_type;
+  hdr->version1 = 1;
+  hdr->id_len = 0; /* ISIS_SYS_ID_LEN -  0==6 */
+  hdr->version2 = 1;
+  hdr->max_area_addrs = 0; /* isis->max_area_addrs -  0==3 */
+}
+
+
+/*
+ * SEND SIDE                             
+ */
+void
+fill_fixed_hdr_andstream (struct isis_fixed_hdr *hdr, u_char pdu_type,
+		struct stream *stream)
+{
+  fill_fixed_hdr (hdr,pdu_type);
+
+  stream_putc (stream, hdr->idrp);
+  stream_putc (stream, hdr->length);
+  stream_putc (stream, hdr->version1);
+  stream_putc (stream, hdr->id_len);
+  stream_putc (stream, hdr->pdu_type);
+  stream_putc (stream, hdr->version2);
+  stream_putc (stream, hdr->reserved);
+  stream_putc (stream, hdr->max_area_addrs);
+
+  return;
+}
+
+
+int
+send_hello (struct isis_circuit *circuit, int level)
+{
+  struct isis_fixed_hdr fixed_hdr;
+  struct isis_lan_hello_hdr hello_hdr;
+  struct isis_p2p_hello_hdr p2p_hello_hdr;
+
+  u_int32_t interval;
+  unsigned long len_pointer, length;
+  int retval;
+
+  if (circuit->interface->mtu == 0) {
+    zlog_warn ("circuit has zero MTU");
+    return ISIS_WARNING;
+  }
+
+  if (!circuit->snd_stream)
+    circuit->snd_stream = stream_new (ISO_MTU(circuit));
+  else
+    stream_reset (circuit->snd_stream);
+
+  if (circuit->circ_type == CIRCUIT_T_BROADCAST)
+    if (level == 1)
+      fill_fixed_hdr_andstream(&fixed_hdr, L1_LAN_HELLO, circuit->snd_stream);
+    else
+      fill_fixed_hdr_andstream(&fixed_hdr, L2_LAN_HELLO, circuit->snd_stream);
+  else
+      fill_fixed_hdr_andstream(&fixed_hdr, P2P_HELLO, circuit->snd_stream);
+
+  /*
+   * Fill LAN Level 1 or 2 Hello PDU header
+   */
+  memset (&hello_hdr, 0, sizeof (struct isis_lan_hello_hdr));
+  interval = circuit->hello_multiplier[level - 1] * 
+    circuit->hello_interval[level - 1];
+  if (interval > USHRT_MAX)
+    interval = USHRT_MAX;
+  hello_hdr.circuit_t = circuit->circuit_is_type;
+  memcpy (hello_hdr.source_id, isis->sysid, ISIS_SYS_ID_LEN);
+  hello_hdr.hold_time = htons((u_int16_t)interval);
+
+  hello_hdr.pdu_len   = 0;                   /* Update the PDU Length later */
+  len_pointer = stream_get_putp (circuit->snd_stream) + 3 + ISIS_SYS_ID_LEN;   
+
+
+  /* copy the shared part of the hello to the p2p hello if needed */
+  if (circuit->circ_type == CIRCUIT_T_P2P) {
+    memcpy (&p2p_hello_hdr, &hello_hdr, 5 + ISIS_SYS_ID_LEN);
+    p2p_hello_hdr.local_id = circuit->circuit_id; 
+    /* FIXME: need better understanding */
+    stream_put  (circuit->snd_stream, &p2p_hello_hdr, ISIS_P2PHELLO_HDRLEN);
+  } else {
+    hello_hdr.prio = circuit->u.bc.priority[level - 1];
+    if(level == 1 && circuit->u.bc.l1_desig_is) {
+      memcpy(hello_hdr.lan_id, circuit->u.bc.l1_desig_is, ISIS_SYS_ID_LEN + 1);
+    } else if (level == 2 && circuit->u.bc.l2_desig_is){
+      memcpy(hello_hdr.lan_id, circuit->u.bc.l2_desig_is, ISIS_SYS_ID_LEN + 1);
+    }
+    stream_put  (circuit->snd_stream, &hello_hdr, ISIS_LANHELLO_HDRLEN);
+  }
+
+  /*
+   * Then the variable length part 
+   */
+  /* add circuit password */
+  if (circuit->passwd.type)
+    if (tlv_add_authinfo (circuit->passwd.type, circuit->passwd.len,
+			  circuit->passwd.passwd, circuit->snd_stream))
+      return ISIS_WARNING;
+  /*  Area Addresses TLV */
+  assert (circuit->area);
+  if (circuit->area->area_addrs && circuit->area->area_addrs->count > 0)
+    if (tlv_add_area_addrs (circuit->area->area_addrs, circuit->snd_stream))
+      return ISIS_WARNING;
+
+  /*  LAN Neighbors TLV */
+  if (circuit->circ_type == CIRCUIT_T_BROADCAST) {
+    if (level == 1 && circuit->u.bc.lan_neighs[0]->count > 0)
+      if (tlv_add_lan_neighs (circuit->u.bc.lan_neighs[0], 
+          circuit->snd_stream))
+        return ISIS_WARNING;
+    if (level == 2 && circuit->u.bc.lan_neighs[1]->count > 0)
+      if (tlv_add_lan_neighs (circuit->u.bc.lan_neighs[1], 
+          circuit->snd_stream))
+        return ISIS_WARNING;
+  }
+
+  /* Protocols Supported TLV */
+  if (circuit->nlpids.count > 0) 
+    if (tlv_add_nlpid (&circuit->nlpids, circuit->snd_stream))
+      return ISIS_WARNING;
+  /* IP interface Address TLV */
+  if (circuit->ip_router && circuit->ip_addrs && circuit->ip_addrs->count > 0)
+    if (tlv_add_ip_addrs (circuit->ip_addrs, circuit->snd_stream))
+      return ISIS_WARNING;
+
+#ifdef HAVE_IPV6 
+  /* IPv6 Interface Address TLV */
+  if (circuit->ipv6_router && circuit->ipv6_link && 
+      circuit->ipv6_link->count > 0)
+    if (tlv_add_ipv6_addrs (circuit->ipv6_link, circuit->snd_stream))
+      return ISIS_WARNING;
+#endif /* HAVE_IPV6 */
+
+  if (circuit->u.bc.pad_hellos)
+    if (tlv_add_padding (circuit->snd_stream))
+      return ISIS_WARNING;
+
+  length = stream_get_putp (circuit->snd_stream);
+  /* Update PDU length */
+  stream_putw_at (circuit->snd_stream, len_pointer, (u_int16_t)length);
+
+  retval = circuit->tx (circuit, level);
+  if (retval)
+    zlog_warn ("sending of LAN Level %d Hello failed", level);
+
+  /* DEBUG_ADJ_PACKETS */
+  if (isis->debugs & DEBUG_ADJ_PACKETS) {
+    if (circuit->circ_type == CIRCUIT_T_BROADCAST) {
+      zlog_info ("ISIS-Adj (%s): Sent L%d LAN IIH on %s, length %ld",
+                 circuit->area->area_tag, level, circuit->interface->name,
+                 STREAM_SIZE(circuit->snd_stream));
+    } else {
+      zlog_info ("ISIS-Adj (%s): Sent P2P IIH on %s, length %ld",
+                 circuit->area->area_tag, circuit->interface->name,
+                 STREAM_SIZE(circuit->snd_stream));
+    }
+  }
+
+
+  return retval;
+}
+
+int
+send_lan_hello (struct isis_circuit *circuit, int level)
+{
+  return send_hello (circuit,level);
+}
+
+int
+send_lan_l1_hello (struct thread *thread)
+{
+
+  struct isis_circuit *circuit;
+  int retval;
+
+  circuit = THREAD_ARG (thread);
+  assert (circuit);
+  circuit->u.bc.t_send_lan_hello[0] = NULL;
+
+  if (circuit->u.bc.run_dr_elect[0])
+    retval = isis_dr_elect (circuit, 1); 
+
+  retval = send_lan_hello (circuit, 1);
+
+  /* set next timer thread */
+  circuit->u.bc.t_send_lan_hello[0] = 
+    thread_add_timer (master, send_lan_l1_hello, circuit, 
+                     isis_jitter (circuit->hello_interval[0], IIH_JITTER));
+
+  return retval;
+}
+
+int
+send_lan_l2_hello (struct thread *thread)
+{
+  struct isis_circuit *circuit;
+  int retval;
+
+  circuit = THREAD_ARG (thread);
+  assert (circuit);
+  circuit->u.bc.t_send_lan_hello[1] = NULL;
+
+  if (circuit->u.bc.run_dr_elect[1])
+    retval = isis_dr_elect (circuit, 2);
+
+  retval = send_lan_hello (circuit, 2);
+
+  /* set next timer thread*/
+  circuit->u.bc.t_send_lan_hello[1] = 
+    thread_add_timer (master, send_lan_l2_hello, circuit, 
+                      isis_jitter (circuit->hello_interval[1], IIH_JITTER));
+
+  return retval;
+}
+
+int
+send_p2p_hello (struct thread *thread)
+{
+  struct isis_circuit *circuit;
+
+  circuit = THREAD_ARG (thread);
+  assert (circuit);
+  circuit->u.p2p.t_send_p2p_hello = NULL;
+
+  send_hello(circuit,1);
+
+  /* set next timer thread*/
+  circuit->u.p2p.t_send_p2p_hello = thread_add_timer
+    (master, send_p2p_hello, circuit, isis_jitter (circuit->hello_interval[1],
+                                                   IIH_JITTER));
+
+  return ISIS_OK;
+}
+
+int
+build_csnp (int level, u_char *start, u_char *stop, struct list *lsps, 
+            struct isis_circuit *circuit)
+{
+  struct isis_fixed_hdr fixed_hdr;
+  struct isis_passwd *passwd;
+  int retval = ISIS_OK;
+  unsigned long lenp;
+  u_int16_t length;
+
+  if (level ==1)
+    fill_fixed_hdr_andstream (&fixed_hdr, L1_COMPLETE_SEQ_NUM, 
+                              circuit->snd_stream);
+  else
+    fill_fixed_hdr_andstream (&fixed_hdr, L2_COMPLETE_SEQ_NUM, 
+                              circuit->snd_stream);
+
+  /*
+   * Fill Level 1 or 2 Complete Sequence Numbers header
+   */
+
+  lenp = stream_get_putp (circuit->snd_stream);
+  stream_putw (circuit->snd_stream, 0); /* PDU length - when we know it */
+  /* no need to send the source here, it is always us if we csnp */
+  stream_put (circuit->snd_stream, isis->sysid, ISIS_SYS_ID_LEN);
+  /* with zero circuit id - ref 9.10, 9.11 */
+  stream_putc (circuit->snd_stream, 0x00);
+
+  stream_put (circuit->snd_stream, start, ISIS_SYS_ID_LEN + 2);
+  stream_put (circuit->snd_stream, stop, ISIS_SYS_ID_LEN + 2);
+
+  /*
+   * And TLVs
+   */
+  if (level == 1)
+    passwd = &circuit->area->area_passwd;
+  else
+    passwd = &circuit->area->domain_passwd;
+
+  if (passwd->type)
+    retval = tlv_add_authinfo (passwd->type, passwd->len,
+			       passwd->passwd, circuit->snd_stream);
+
+  if (!retval && lsps) { 
+    retval = tlv_add_lsp_entries (lsps, circuit->snd_stream);
+  } 
+  length = (u_int16_t)stream_get_putp (circuit->snd_stream);
+  assert (length >= ISIS_CSNP_HDRLEN);
+  /* Update PU length */
+  stream_putw_at (circuit->snd_stream, lenp, length);
+
+  return retval;
+}
+
+/*
+ * FIXME: support multiple CSNPs
+ */
+
+int
+send_csnp (struct isis_circuit *circuit, int level)
+{
+  int retval = ISIS_OK;
+  u_char start[ISIS_SYS_ID_LEN + 2];
+  u_char stop[ISIS_SYS_ID_LEN + 2];
+  struct list *list = NULL;
+  struct listnode *node;
+  struct isis_lsp *lsp;
+
+  memset (start,0x00, ISIS_SYS_ID_LEN + 2);
+  memset (stop, 0xff, ISIS_SYS_ID_LEN + 2);
+
+  if (circuit->area->lspdb[level-1] && 
+      dict_count (circuit->area->lspdb[level-1]) > 0) {
+    list = list_new ();
+    lsp_build_list (start, stop, list, circuit->area->lspdb[level-1]);
+
+    if (circuit->snd_stream == NULL)
+      circuit->snd_stream = stream_new (ISO_MTU(circuit));
+    else
+      stream_reset (circuit->snd_stream);
+
+    retval = build_csnp  (level, start, stop, list, circuit);
+
+    if (isis->debugs & DEBUG_SNP_PACKETS) { 
+      zlog_info ("ISIS-Snp (%s): Sent L%d CSNP on %s, length %ld",
+                 circuit->area->area_tag, level, circuit->interface->name,
+                 STREAM_SIZE(circuit->snd_stream));
+      LIST_LOOP (list, lsp, node) {
+        zlog_info("ISIS-Snp (%s):         CSNP entry %s, seq 0x%08x,"
+                  " cksum 0x%04x, lifetime %us", 
+                  circuit->area->area_tag,
+                  rawlspid_print (lsp->lsp_header->lsp_id),
+                  ntohl (lsp->lsp_header->seq_num),
+                  ntohs (lsp->lsp_header->checksum),
+                  ntohs (lsp->lsp_header->rem_lifetime));
+      }
+    }
+
+    list_delete (list);
+
+    if (retval == ISIS_OK)
+      retval = circuit->tx (circuit, level);
+  }
+  return retval;
+}
+
+int
+send_l1_csnp (struct thread *thread)
+{
+  struct isis_circuit *circuit;
+  int retval = ISIS_OK;
+
+  circuit = THREAD_ARG (thread);
+  assert (circuit);
+
+  circuit->t_send_csnp[0] = NULL;
+
+  if (circuit->circ_type == CIRCUIT_T_BROADCAST && circuit->u.bc.is_dr[0]) {
+    send_csnp(circuit,1);
+  }
+  /* set next timer thread */
+  circuit->t_send_csnp[0] = thread_add_timer (master, 
+                                              send_l1_csnp,
+                                              circuit, 
+                                              isis_jitter 
+                                              (circuit->csnp_interval[0],
+                                               CSNP_JITTER));
+
+  return retval;
+}
+
+int
+send_l2_csnp (struct thread *thread)
+{
+  struct isis_circuit *circuit;
+  int retval = ISIS_OK;
+
+  circuit = THREAD_ARG (thread);
+  assert (circuit);
+
+  circuit->t_send_csnp[1] = NULL;
+
+  if (circuit->circ_type == CIRCUIT_T_BROADCAST && circuit->u.bc.is_dr[1]) {
+    send_csnp(circuit,2);
+  }
+  /* set next timer thread */
+  circuit->t_send_csnp[1] = thread_add_timer (master, 
+                                              send_l2_csnp,
+                                              circuit, 
+                                              isis_jitter 
+                                              (circuit->csnp_interval[1],
+                                               CSNP_JITTER));
+  return retval;
+}
+
+int
+build_psnp (int level, struct isis_circuit *circuit, struct list *lsps)
+{
+  struct isis_fixed_hdr fixed_hdr;
+  unsigned long lenp;
+  u_int16_t length;
+  int retval = 0;
+  struct isis_lsp *lsp;
+  struct isis_passwd *passwd;
+  struct listnode *node;
+
+  if (level == 1)
+    fill_fixed_hdr_andstream (&fixed_hdr, L1_PARTIAL_SEQ_NUM, 
+                              circuit->snd_stream);
+  else
+    fill_fixed_hdr_andstream (&fixed_hdr, L2_PARTIAL_SEQ_NUM,
+                              circuit->snd_stream);
+
+  /*
+   * Fill Level 1 or 2 Partial Sequence Numbers header
+   */
+  lenp = stream_get_putp (circuit->snd_stream);
+  stream_putw (circuit->snd_stream, 0); /* PDU length - when we know it */
+  stream_put (circuit->snd_stream, isis->sysid, ISIS_SYS_ID_LEN);
+  stream_putc (circuit->snd_stream, circuit->idx);
+
+  /*
+   * And TLVs
+   */
+
+  if (level == 1)
+    passwd = &circuit->area->area_passwd;
+  else
+    passwd = &circuit->area->domain_passwd;
+
+  if (passwd->type)
+    retval = tlv_add_authinfo (passwd->type, passwd->len,
+			       passwd->passwd, circuit->snd_stream);
+
+  if (!retval && lsps) { 
+    retval = tlv_add_lsp_entries (lsps, circuit->snd_stream);
+  }
+
+  if (isis->debugs & DEBUG_SNP_PACKETS) {
+    LIST_LOOP (lsps, lsp, node) {
+      zlog_info("ISIS-Snp (%s):         PSNP entry %s, seq 0x%08x,"
+                " cksum 0x%04x, lifetime %us", 
+                circuit->area->area_tag,
+                rawlspid_print (lsp->lsp_header->lsp_id),
+                ntohl (lsp->lsp_header->seq_num),
+                ntohs (lsp->lsp_header->checksum),
+                ntohs (lsp->lsp_header->rem_lifetime));
+    }
+  }
+
+  length = (u_int16_t)stream_get_putp (circuit->snd_stream);
+  assert (length >= ISIS_PSNP_HDRLEN);
+  /* Update PDU length */
+  stream_putw_at (circuit->snd_stream, lenp, length);
+
+  return ISIS_OK;
+}
+
+/*
+ *  7.3.15.4 action on expiration of partial SNP interval
+ *  level 1
+ */
+int
+send_psnp (int level, struct isis_circuit *circuit)
+{
+  int retval = ISIS_OK;
+  struct isis_lsp *lsp;
+  struct list *list = NULL;
+  struct listnode *node;
+
+  if ((circuit->circ_type == CIRCUIT_T_BROADCAST && 
+       !circuit->u.bc.is_dr[level - 1]) ||
+      circuit->circ_type != CIRCUIT_T_BROADCAST) {
+
+    if (circuit->area->lspdb[level-1] && 
+        dict_count (circuit->area->lspdb[level-1]) > 0) {
+      list = list_new ();
+      lsp_build_list_ssn (circuit, list, circuit->area->lspdb[level-1]);
+
+      if (listcount(list) > 0) {
+        if (circuit->snd_stream == NULL)
+          circuit->snd_stream = stream_new (ISO_MTU(circuit));
+        else
+          stream_reset (circuit->snd_stream);
+
+
+        if (isis->debugs & DEBUG_SNP_PACKETS) 
+          zlog_info ("ISIS-Snp (%s): Sent L%d PSNP on %s, length %ld",
+                     circuit->area->area_tag, level, circuit->interface->name,
+                     STREAM_SIZE(circuit->snd_stream));
+
+        retval = build_psnp (level, circuit, list);
+        if (retval == ISIS_OK)
+          retval = circuit->tx (circuit, level);
+
+        if (retval == ISIS_OK) {
+          /*
+           * sending succeeded, we can clear SSN flags of this circuit
+           * for the LSPs in list
+           */
+          for (node = listhead (list); node; nextnode(node)) {
+            lsp = getdata (node);
+            ISIS_CLEAR_FLAG (lsp->SSNflags, circuit);
+          }
+        }
+      }
+      list_delete (list);
+    }
+  }
+
+  return retval;
+}
+
+int
+send_l1_psnp (struct thread *thread)
+{
+
+  struct isis_circuit *circuit;
+  int retval = ISIS_OK;
+
+  circuit = THREAD_ARG (thread);
+  assert (circuit);
+
+  circuit->t_send_psnp[0] = NULL;
+
+  send_psnp (1, circuit);
+  /* set next timer thread */
+  circuit->t_send_psnp[0] = thread_add_timer (master,
+                                              send_l1_psnp,
+                                              circuit,
+                                              isis_jitter
+                                              (circuit->psnp_interval[0], 
+                                               PSNP_JITTER));
+
+  return retval;
+}
+
+/*
+ *  7.3.15.4 action on expiration of partial SNP interval
+ *  level 2
+ */
+int
+send_l2_psnp (struct thread *thread)
+{
+
+  struct isis_circuit *circuit;
+  int retval = ISIS_OK;
+
+  circuit = THREAD_ARG (thread);
+  assert (circuit);
+
+  circuit->t_send_psnp[1] = NULL;
+
+  send_psnp (2, circuit);
+
+  /* set next timer thread */
+  circuit->t_send_psnp[1] = thread_add_timer (master,
+                                              send_l2_psnp,
+                                              circuit,
+                                              isis_jitter
+                                              (circuit->psnp_interval[1],
+                                               PSNP_JITTER));
+
+  return retval;
+}
+
+
+void
+build_link_state (struct isis_lsp *lsp, struct isis_circuit *circuit,
+                  struct stream *stream)
+{
+  unsigned long length;
+
+  stream_put  (stream, lsp->pdu, ntohs(lsp->lsp_header->pdu_len));
+  length = stream_get_putp (stream); 
+
+  return;
+}
+
+
+/*
+ * ISO 10589 - 7.3.14.3
+ */
+int
+send_lsp (struct thread *thread)
+{
+  struct isis_circuit *circuit;
+  struct isis_lsp *lsp;
+  struct listnode *node;
+  int retval = 0;
+
+  circuit = THREAD_ARG (thread);
+  assert (circuit);
+
+  if (circuit->state == C_STATE_UP) {
+    node = listhead (circuit->lsp_queue);
+    assert (node);
+
+    lsp = getdata (node);
+
+    /*
+     * Do not send if levels do not match
+     */
+    if (!(lsp->level & circuit->circuit_is_type))
+      goto dontsend;
+
+    /*
+     * Do not send if we do not have adjacencies in state up on the circuit
+     */
+    if (circuit->upadjcount[lsp->level - 1] == 0)
+      goto dontsend;
+    /* only send if it needs sending */
+    if ((time(NULL) - lsp->last_sent) >= 
+         circuit->area->lsp_gen_interval[lsp->level-1]) {
+
+      if (isis->debugs & DEBUG_UPDATE_PACKETS) {
+        zlog_info ("ISIS-Upd (%s): Sent L%d LSP %s, seq 0x%08x, cksum 0x%04x,"
+                   " lifetime %us on %s",
+                   circuit->area->area_tag,
+		   lsp->level, 
+                   rawlspid_print (lsp->lsp_header->lsp_id),
+                   ntohl(lsp->lsp_header->seq_num),
+		   ntohs(lsp->lsp_header->checksum),
+                   ntohs(lsp->lsp_header->rem_lifetime), 
+                   circuit->interface->name);
+      }
+      /* copy our lsp to the send buffer */
+      circuit->snd_stream->getp = lsp->pdu->getp;
+      circuit->snd_stream->putp = lsp->pdu->putp;
+      circuit->snd_stream->endp = lsp->pdu->endp;
+      memcpy (circuit->snd_stream->data, lsp->pdu->data, lsp->pdu->endp);
+
+      retval = circuit->tx (circuit, lsp->level);
+
+      /*
+       * If the sending succeeded, we can del the lsp from circuits lsp_queue
+       */
+      if (retval == ISIS_OK) {
+        list_delete_node (circuit->lsp_queue, node);
+
+	/*
+	 * On broadcast circuits also the SRMflag can be cleared
+	 */
+	if (circuit->circ_type == CIRCUIT_T_BROADCAST)
+	  ISIS_CLEAR_FLAG (lsp->SRMflags, circuit);
+
+	if (flags_any_set (lsp->SRMflags) == 0) {
+	  /*
+	   * need to remember when we were last sent
+	   */
+	  lsp->last_sent = time (NULL);
+	}
+      } else {
+        zlog_info ("sending of level %d link state failed", lsp->level);
+      }
+    } else {
+      /* my belief is that if it wasn't his time, the lsp can be removed
+       * from the queue
+       */
+    dontsend:
+      list_delete_node (circuit->lsp_queue, node);
+    }
+#if 0
+    /*
+     * If there are still LSPs send next one after lsp-interval (33 msecs)
+     */
+    if (listcount (circuit->lsp_queue) > 0)
+      thread_add_timer (master, send_lsp, circuit,
+                             1);
+#endif
+  }
+
+  return retval;
+} 
+
+int
+ack_lsp (struct isis_link_state_hdr *hdr, struct isis_circuit *circuit, 
+         int level)
+{
+  unsigned long lenp;
+  int retval;
+  u_int16_t length;
+  struct isis_fixed_hdr fixed_hdr;
+
+  if (!circuit->snd_stream)
+    circuit->snd_stream = stream_new (ISO_MTU(circuit));
+  else
+    stream_reset (circuit->snd_stream);
+
+//  fill_llc_hdr (stream);
+  if (level == 1)
+    fill_fixed_hdr_andstream (&fixed_hdr, L1_PARTIAL_SEQ_NUM, 
+                              circuit->snd_stream);
+  else
+    fill_fixed_hdr_andstream (&fixed_hdr, L2_PARTIAL_SEQ_NUM, 
+                              circuit->snd_stream);
+
+
+  lenp = stream_get_putp (circuit->snd_stream);
+  stream_putw (circuit->snd_stream, 0); /* PDU length  */
+  stream_put  (circuit->snd_stream, isis->sysid, ISIS_SYS_ID_LEN);
+  stream_putc (circuit->snd_stream, circuit->idx);
+  stream_putc (circuit->snd_stream, 9); /* code */
+  stream_putc (circuit->snd_stream, 16); /* len */
+
+  stream_putw (circuit->snd_stream, ntohs(hdr->rem_lifetime));
+  stream_put  (circuit->snd_stream, hdr->lsp_id, ISIS_SYS_ID_LEN + 2);
+  stream_putl (circuit->snd_stream, ntohl(hdr->seq_num));
+  stream_putw (circuit->snd_stream, ntohs(hdr->checksum));
+
+  length = (u_int16_t)stream_get_putp (circuit->snd_stream);
+  /* Update PDU length */
+  stream_putw_at (circuit->snd_stream, lenp, length);
+
+  retval = circuit->tx (circuit, level);
+
+  return retval;
+}
+
+#if 0
+/*
+ * ISH PDU Processing 
+ */
+
+
+  /*
+   * Let's first check if the local and remote system have any common area
+   * addresses 
+   */
+  if (area_match(tlvs.area_addrs, isis->man_area_addrs) == 0) {
+    if (circuit->circuit_t == IS_LEVEL_2) {
+      /* do as in table 8 (p. 40) */
+      switch (circuit_type) {
+      case IS_LEVEL_1:
+	if (adj->adj_state != ISIS_ADJ_UP) {
+	  /* Reject */
+	  zlog_warn("areaMismatch");
+	  retval = ISIS_WARNING;
+	} else if (adj->adj_usage == ISIS_ADJ_LEVEL1) {
+	  isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Area Mismatch",
+				 circuit->adjdb);
+	} else if (adj->adj_usage == ISIS_ADJ_LEVEL1AND2 || 
+		   adj->adj_usage == ISIS_ADJ_LEVEL2) {
+	  isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System",
+				 circuit->adjdb);
+	}
+	break;
+      case IS_LEVEL_2:
+	if (adj->adj_state != ISIS_ADJ_UP) {
+	  isis_adj_state_change (adj, ISIS_ADJ_UP, NULL, circuit->adjdb);
+	  adj->adj_usage = ISIS_ADJ_LEVEL2;
+	} else if (adj->adj_usage == ISIS_ADJ_LEVEL1 || 
+	           adj->adj_usage == ISIS_ADJ_LEVEL1AND2) { 
+	  isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System",
+				 circuit->adjdb);
+	} else if (adj->adj_usage == ISIS_ADJ_LEVEL2) {
+	    ; /* Accept */
+	}
+	break;
+      case IS_LEVEL_1_AND_2:
+	if (adj->adj_state != ISIS_ADJ_UP) {
+	  isis_adj_state_change (adj, ISIS_ADJ_UP, NULL, circuit->adjdb);
+	  adj->adj_usage = ISIS_ADJ_LEVEL2;
+	} else if (adj->adj_usage == ISIS_ADJ_LEVEL1) {
+	  isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Wrong System",
+				 circuit->adjdb);
+	} else if (adj->adj_usage == ISIS_ADJ_LEVEL1AND2) { 
+	  isis_adj_state_change (adj, ISIS_ADJ_DOWN, "Area Mismatch",
+				 circuit->adjdb);
+	} else if (adj->adj_usage == ISIS_ADJ_LEVEL2) {
+	    ; /* Accept */
+	}
+	break;
+      }
+      goto mismatch;
+    } else {
+      isis_delete_adj (adj, circuit->adjdb);
+      zlog_warn("areaMismatch");
+      return ISIS_WARNING;
+    }
+  }
+
+mismatch:
+#endif
+
+
+
+