Various diffs for more complete LDP decoding

[sthaug () nethelp no]

Below are patches to perform significantly more complete LDP decoding.
Synposis:

- Minor diff to print-tcp.c (actually call the LDP decoder)
- Minor diff to print-bgp.c (unstaticize routines used by print-ldp.c)
- Major diff to print-ldp.c

Hannes: I'd be happy to decode even more if you can get me some LDP
traces which utilize more of the LDP functionality.

Steinar Haug, Nethelp consulting, sthaug () nethelp no

--- print-bgp.c.orig    Mon May 17 14:10:05 2004
+++ print-bgp.c Thu May 27 17:49:19 2004
@@ -460,7 +460,7 @@
     { 0, NULL},
 };
 
-static int
+int
 decode_prefix4(const u_char *pptr, char *buf, u_int buflen)
 {
        struct in_addr addr;
@@ -688,7 +688,7 @@
 }
 
 #ifdef INET6
-static int
+int
 decode_prefix6(const u_char *pd, char *buf, u_int buflen)
 {
        struct in6_addr addr;
--- print-tcp.c.orig    Mon Apr 26 08:17:31 2004
+++ print-tcp.c Thu May 27 19:56:11 2004
@@ -650,8 +650,9 @@
                } else if (sport == MSDP_PORT || dport == MSDP_PORT) {
                        msdp_print(bp, length);
                }
-                else if (sport == LDP_PORT || dport == LDP_PORT)
-                        printf(": LDP, length: %u", length);
+                else if (length > 0 && (sport == LDP_PORT || dport == LDP_PORT)) {
+                        ldp_print(bp, length);
+               }
        }
        return;
 bad:
--- print-ldp.c.orig    Sun Nov 16 10:36:27 2003
+++ print-ldp.c Thu May 27 19:32:41 2004
@@ -11,6 +11,7 @@
  * FOR A PARTICULAR PURPOSE.
  *
  * Original code by Hannes Gredler (hannes () juniper net)
+ *  and Steinar Haug (sthaug () nethelp no)
  */
 
 #ifndef lint
@@ -142,6 +143,7 @@
 #define        LDP_TLV_COMMON_SESSION       0x0500
 #define        LDP_TLV_ATM_SESSION_PARM     0x0501
 #define        LDP_TLV_FR_SESSION_PARM      0x0502
+#define LDP_TLV_FT_SESSION          0x0503
 #define        LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
 
 static const struct tok ldp_tlv_values[] = {
@@ -163,10 +165,56 @@
     { LDP_TLV_COMMON_SESSION,        "Common Session Parameters" },
     { LDP_TLV_ATM_SESSION_PARM,      "ATM Session Parameters" },
     { LDP_TLV_FR_SESSION_PARM,       "Frame-Relay Session Parameters" },
+    { LDP_TLV_FT_SESSION,            "Fault-Tolerant Session Parameters" },
     { LDP_TLV_LABEL_REQUEST_MSG_ID,  "Label Request Message ID" },
     { 0, NULL}
 };
 
+#define LDP_FEC_WILDCARD       0x01
+#define LDP_FEC_PREFIX         0x02
+#define LDP_FEC_HOSTADDRESS    0x03
+/* From draft-martini-l2circuit-trans-mpls-13.txt */
+#define LDP_FEC_MARTINI_VC     0x80
+
+static const struct tok ldp_fec_values[] = {
+    { LDP_FEC_WILDCARD,                "Wildcard" },
+    { LDP_FEC_PREFIX,          "Prefix" },
+    { LDP_FEC_HOSTADDRESS,     "Host address" },
+    { LDP_FEC_MARTINI_VC,      "Martini VC" },
+    { 0, NULL}
+};
+
+/* From draft-martini-l2circuit-trans-mpls-13.txt */
+#define LDP_MARTINI_VCTYPE_FR_DLCI     0x0001
+#define LDP_MARTINI_VCTYPE_ATM_AAL5    0x0002
+#define LDP_MARTINI_VCTYPE_ATM_CELL    0x0003
+#define LDP_MARTINI_VCTYPE_ETH_VLAN    0x0004
+#define LDP_MARTINI_VCTYPE_ETHERNET    0x0005
+#define LDP_MARTINI_VCTYPE_HDLC                0x0006
+#define LDP_MARTINI_VCTYPE_PPP         0x0007
+#define LDP_MARTINI_VCTYPE_CEM         0x0008
+#define LDP_MARTINI_VCTYPE_ATM_VCC     0x0009
+#define LDP_MARTINI_VCTYPE_ATM_VPC     0x000A
+
+/* Overlaps print-bgp.c bgp_l2vpn_encaps_values */
+static const struct tok ldp_vctype_values[] = {
+    { LDP_MARTINI_VCTYPE_FR_DLCI,      "Frame Relay DLCI" },
+    { LDP_MARTINI_VCTYPE_ATM_AAL5,     "ATM AAL5 VCC transport" },
+    { LDP_MARTINI_VCTYPE_ATM_CELL,     "ATM transparent cell transport" },
+    { LDP_MARTINI_VCTYPE_ETH_VLAN,     "Ethernet VLAN" },
+    { LDP_MARTINI_VCTYPE_ETHERNET,     "Ethernet" },
+    { LDP_MARTINI_VCTYPE_HDLC,         "HDLC" },
+    { LDP_MARTINI_VCTYPE_PPP,          "PPP" },
+    { LDP_MARTINI_VCTYPE_CEM,          "SONET/SDH Circuit Emulation Service" },
+    { LDP_MARTINI_VCTYPE_ATM_VCC,      "ATM VCC cell transport" },
+    { LDP_MARTINI_VCTYPE_ATM_VPC,      "ATM VPC cell transport" },
+    { 0, NULL}
+};
+
+/* RFC1700 address family numbers, same definition in print-bgp.c */
+#define AFNUM_INET     1
+#define AFNUM_INET6    2
+
 #define FALSE 0
 #define TRUE  1
 
@@ -198,7 +246,11 @@
     };
 
     const struct ldp_tlv_header *ldp_tlv_header;
-    u_short tlv_type,tlv_len,tlv_tlen;
+    u_short tlv_type,tlv_len,tlv_tlen,af,ft_flags;
+    u_char fec_type,prelen;
+    u_int ui;
+    char buf[100];
+    int i;
 
     ldp_tlv_header = (const struct ldp_tlv_header *)tptr;    
     tlv_len=EXTRACT_16BITS(ldp_tlv_header->length);
@@ -238,23 +290,121 @@
         printf("\n\t      Sequence Number: %u", EXTRACT_32BITS(tptr));
         break;
 
+    case LDP_TLV_ADDRESS_LIST:
+       af = EXTRACT_16BITS(tptr);
+       tptr+=2;
+       printf("\n\t      Adress Family: ");
+       if (af == AFNUM_INET) {
+           printf("IPv4, addresses:");
+           for (i=0; i<(tlv_tlen-2)/4; i++) {
+               printf(" %s",ipaddr_string(tptr));
+               tptr+=4;
+           }
+       }
+#ifdef INET6
+       else if (af == AFNUM_INET6) {
+           printf("IPv6, addresses:");
+           for (i=0; i<(tlv_tlen-2)/16; i++) {
+               printf(" %s",ip6addr_string(tptr));
+               tptr+=16;
+           }
+       }
+#endif
+       break;
+
+    case LDP_TLV_COMMON_SESSION:
+       printf("\n\t      Version: %u, Keepalive: %us, Flags: [Downstream %s, Loop Detection %s]",
+              EXTRACT_16BITS(tptr), EXTRACT_16BITS(tptr+2),
+              (EXTRACT_16BITS(tptr+6)&0x8000) ? "On Demand" : "Unsolicited",
+              (EXTRACT_16BITS(tptr+6)&0x4000) ? "Enabled" : "Disabled"
+              );
+       break;
+
+    case LDP_TLV_FEC:
+        fec_type = *tptr;
+       printf("\n\t      %s FEC (0x%02x)",
+              tok2str(ldp_fec_values, "Unknown", fec_type),
+              fec_type);
+
+       tptr+=1;
+       switch(fec_type) {
+
+       case LDP_FEC_WILDCARD:
+           break;
+       case LDP_FEC_PREFIX:
+           af = EXTRACT_16BITS(tptr);
+           tptr+=2;
+           if (af == AFNUM_INET) {
+               i=decode_prefix4(tptr,buf,sizeof(buf));
+               printf(": IPv4 prefix %s",buf);
+           }
+#ifdef INET6
+           else if (af == AFNUM_INET6) {
+               i=decode_prefix6(tptr,buf,sizeof(buf));
+               printf(": IPv6 prefix %s",buf);
+           }
+#endif
+           break;
+       case LDP_FEC_HOSTADDRESS:
+           break;
+       case LDP_FEC_MARTINI_VC:
+           printf(": %s, %scontrol word, VC %u",
+                  tok2str(ldp_vctype_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
+                  EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
+                  EXTRACT_32BITS(tptr+7));
+           break;
+       }
+
+       break;
+
+    case LDP_TLV_GENERIC_LABEL:
+       printf("\n\t      Label: %u", EXTRACT_32BITS(tptr) & 0xfffff);
+       break;
+
+    case LDP_TLV_STATUS:
+       ui = EXTRACT_32BITS(tptr);
+       tptr+=4;
+       printf("\n\t      Status: 0x%02x, Flags: [%s and %s forward]",
+              ui&0x3fffffff,
+              ui&0x80000000 ? "Fatal error" : "Advisory Notification",
+              ui&0x40000000 ? "do" : "don't");
+       ui = EXTRACT_32BITS(tptr);
+       tptr+=4;
+       if (ui)
+           printf(", causing Message ID: 0x%08x", ui);
+       break;
+
+    case LDP_TLV_FT_SESSION:
+       ft_flags = EXTRACT_16BITS(tptr);
+       printf("\n\t      Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
+              ft_flags&0x8000 ? "" : "No ",
+              ft_flags&0x8 ? "" : "Don't ",
+              ft_flags&0x4 ? "" : "No ",
+              ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
+              ft_flags&0x1 ? "" : "Don't ");
+       tptr+=4;
+       ui = EXTRACT_32BITS(tptr);
+       if (ui)
+           printf(", Reconnect Timeout: %ums", ui);
+       tptr+=4;
+       ui = EXTRACT_32BITS(tptr);
+       if (ui)
+           printf(", Recovery Time: %ums", ui);
+       break;
+
+
     /*
      *  FIXME those are the defined TLVs that lack a decoder
      *  you are welcome to contribute code ;-)
      */
 
-    case LDP_TLV_FEC:
-    case LDP_TLV_ADDRESS_LIST:
     case LDP_TLV_HOP_COUNT:
     case LDP_TLV_PATH_VECTOR:
-    case LDP_TLV_GENERIC_LABEL:
     case LDP_TLV_ATM_LABEL:
     case LDP_TLV_FR_LABEL:
-    case LDP_TLV_STATUS:
     case LDP_TLV_EXTD_STATUS:
     case LDP_TLV_RETURNED_PDU:
     case LDP_TLV_RETURNED_MSG:
-    case LDP_TLV_COMMON_SESSION:
     case LDP_TLV_ATM_SESSION_PARM:
     case LDP_TLV_FR_SESSION_PARM:
     case LDP_TLV_LABEL_REQUEST_MSG_ID:
@@ -304,8 +454,8 @@
     /* ok they seem to want to know everything - lets fully decode it */
     tlen=EXTRACT_16BITS(ldp_com_header->pdu_length);
 
-    tptr+=sizeof(const struct ldp_common_header);
-    tlen-=sizeof(const struct ldp_common_header);
+    tptr += sizeof(const struct ldp_common_header);
+    tlen -= sizeof(const struct ldp_common_header)-4;  /* Type & Length fields not included */
 
     while(tlen>0) {
         /* did we capture enough for fully decoding the msg header ? */
@@ -336,7 +486,12 @@
 
         switch(msg_type) {
  
+        case LDP_MSG_NOTIF:
         case LDP_MSG_HELLO:
+        case LDP_MSG_INIT:
+        case LDP_MSG_KEEPALIVE:
+        case LDP_MSG_ADDRESS:
+        case LDP_MSG_LABEL_MAPPING:
             while(msg_tlen >= 4) {
                 processed = ldp_tlv_print(msg_tptr);
                 if (processed == 0)
@@ -351,12 +506,7 @@
          *  you are welcome to contribute code ;-)
          */
 
-        case LDP_MSG_NOTIF:
-        case LDP_MSG_INIT:
-        case LDP_MSG_KEEPALIVE:
-        case LDP_MSG_ADDRESS:
         case LDP_MSG_ADDRESS_WITHDRAW:
-        case LDP_MSG_LABEL_MAPPING:
         case LDP_MSG_LABEL_REQUEST:
         case LDP_MSG_LABEL_WITHDRAW:
         case LDP_MSG_LABEL_RELEASE:
@@ -372,8 +522,8 @@
             print_unknown_data(tptr+sizeof(sizeof(struct ldp_msg_header)),"\n\t  ",
                                msg_len);
 
-        tptr+=msg_len;
-        tlen-=msg_len;
+        tptr += msg_len+4;
+        tlen -= msg_len+4;
     }
     return;
 trunc:

-
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