add ldpupdate script

code/CMakeLists.txt

@@ -6,4 +6,5 @@ add_subdirectory(bngblaster)
 add_subdirectory(lspgen)
 
 install(PROGRAMS bngblaster-cli DESTINATION sbin)
-install(PROGRAMS bgpupdate DESTINATION bin)
+install(PROGRAMS bgpupdate DESTINATION bin)
+install(PROGRAMS ldpupdate DESTINATION bin)

code/ldpupdate

@@ -0,0 +1,156 @@
+#!/usr/bin/env python3
+"""
+LDP RAW Update Generator
+
+Christian Giese, December 2022
+
+Copyright (C) 2020-2022, RtBrick, Inc.
+SPDX-License-Identifier: BSD-3-Clause
+"""
+import argparse
+import ipaddress
+import json
+import logging
+import struct
+import sys
+
+try:
+    from scapy.all import *
+    log_runtime.setLevel(logging.ERROR)
+    from scapy.contrib.ldp import *
+    log_runtime.setLevel(logging.INFO)
+except:
+    print("Failed to load scapy!")
+    exit(1)
+
+# ==============================================================
+# DEFINITIONS
+# ==============================================================
+
+DESCRIPTION = """
+The LDP RAW update generator is a simple 
+tool to generate LDP RAW update streams 
+for use with the BNG Blaster.
+"""
+
+LOG_LEVELS = {
+    'warning': logging.WARNING,
+    'info': logging.INFO,
+    'debug': logging.DEBUG
+}
+
+MPLS_LABEL_MIN = 1
+MPLS_LABEL_MAX = 1048575
+
+# ==============================================================
+# FUNCTIONS
+# ==============================================================
+
+def init_logging(log_level: int) -> logging.Logger:
+    """Init logging."""
+    level = LOG_LEVELS[log_level]
+    log = logging.getLogger()
+    log.setLevel(level)
+    handler = logging.StreamHandler(sys.stdout)
+    handler.setLevel(level)
+    formatter = logging.Formatter('[%(asctime)s][%(levelname)-7s] %(message)s')
+    formatter.datefmt = '%Y-%m-%d %H:%M:%S'
+    handler.setFormatter(formatter)
+    log.addHandler(handler)
+    return log
+
+
+def label_type(label: int) -> int:
+    """Argument parser type for MPLS labels."""
+    label = int(label)
+    if label < MPLS_LABEL_MIN or label > MPLS_LABEL_MAX:
+        raise argparse.ArgumentTypeError("MPLS label out of range %s - %s" % (MPLS_LABEL_MIN, MPLS_LABEL_MAX))
+    return label
+
+
+# ==============================================================
+# MAIN
+# ==============================================================
+
+def main():
+    # parse arguments
+    parser = argparse.ArgumentParser(description=DESCRIPTION)
+    parser.add_argument('-l', '--lsr-id', metavar='ADDRESS', type=ipaddress.ip_address, required=True, help='LSR identifier')
+    parser.add_argument('-i', '--message-id-base', metavar='N', type=int, default=1000, help='message identifier base')
+    parser.add_argument('-p', '--prefix-base', metavar='PREFIX', type=ipaddress.ip_network, required=True, help='prefix base network')
+    parser.add_argument('-P', '--prefix-num', metavar='N', type=int, default=1, help='prefix count')
+    parser.add_argument('-m', '--label-base', metavar='LABEL', type=label_type, default=10000, help='label base')
+    parser.add_argument('-M', '--label-num', metavar='N', type=int, default=1, help='label count')
+    parser.add_argument('-f', '--file', type=str, default="out.ldp", help='output file')
+    parser.add_argument('--append', action="store_true", help="append to file if exist")
+    parser.add_argument('--pcap', metavar='FILE', type=str, help="write LDP updates to PCAP file")
+    parser.add_argument('--log-level', type=str, default='info', choices=LOG_LEVELS.keys(), help='logging Level')
+    args = parser.parse_args()
+
+    # init logging
+    log = init_logging(args.log_level)
+    if args.prefix_base.version != 4:
+        log.error("prefix must be IPv4")
+        exit(1)
+
+    log.info("init %s labeled IPv4 prefixes" % (args.prefix_num))
+
+    # Here we will store packets for optional PCAP output
+    pcap_packets = []
+    def pcap(message):
+        if args.pcap:
+            pcap_packets.append(Ether()/IP()/TCP(sport=len(pcap_packets)+10000, dport=646, seq=1, flags='PA')/message)
+
+    prefixes = []
+
+    label_index = 0
+    prefix = args.prefix_base
+    label = args.label_base
+    for _ in range(args.prefix_num):
+        log.debug("add prefix %s via label %s" % (prefix, label))
+        prefixes.append((prefix, label))
+
+        label_index += 1
+        if label_index < args.label_num:
+            label = args.label_base + label_index
+            if label > MPLS_LABEL_MAX:
+                label_index = 0
+                label = args.label_base
+        else:
+            label_index = 0
+            label = args.label_base
+
+        prefix = ipaddress.ip_network("%s/%s" % (prefix.broadcast_address+1, prefix.prefixlen))
+
+    if args.append:
+        log.info("open file %s (append)" % args.file)
+        file_flags = "ab"
+    else:
+        log.info("open file %s (replace)" % args.file)
+        file_flags = "wb"
+
+    with open(args.file, file_flags) as f:
+
+        mid = args.message_id_base
+
+        for prefix, label in prefixes:
+            pdu = LDP(id=args.lsr_id)/LDPLabelMM(id=mid, fec=[(str(prefix.network_address),int(prefix.prefixlen))],label=label)
+            mid+=1
+
+            pdu_bin = bytearray(pdu.build())
+            pcap(pdu)
+            f.write(pdu_bin)
+
+    if args.pcap:
+        log.info("create PCAP file %s" % args.pcap)
+        try:
+            wrpcap(args.pcap, pcap_packets)
+        except Exception as e:
+            log.error("failed to create PCAP file")
+            log.debug(e)
+    
+    log.info("finished")
+
+
+if __name__ == "__main__":
+    main()