#!/usr/bin/env python3 # SPDX-License-Identifier: GPL-2.0-or-later # Frr Reloader # Copyright (C) 2014 Cumulus Networks, Inc. # """ This program - reads a frr configuration text file - reads frr's current running configuration via "vtysh -c 'show running'" - compares the two configs and determines what commands to execute to synchronize frr's running configuration with the configuation in the text file """ from __future__ import print_function, unicode_literals import argparse import logging import os, os.path import random import re import string import subprocess import sys from collections import OrderedDict from ipaddress import IPv6Address, ip_network from pprint import pformat # Python 3 def iteritems(d): return iter(d.items()) log = logging.getLogger(__name__) class VtyshException(Exception): pass class Vtysh(object): def __init__(self, bindir=None, confdir=None, sockdir=None, pathspace=None): self.bindir = bindir self.confdir = confdir self.pathspace = pathspace self.common_args = [os.path.join(bindir or "", "vtysh")] if confdir: self.common_args.extend(["--config_dir", confdir]) if sockdir: self.common_args.extend(["--vty_socket", sockdir]) if pathspace: self.common_args.extend(["-N", pathspace]) def _call(self, args, stdin=None, stdout=None, stderr=None): kwargs = {} if stdin is not None: kwargs["stdin"] = stdin if stdout is not None: kwargs["stdout"] = stdout if stderr is not None: kwargs["stderr"] = stderr return subprocess.Popen(self.common_args + args, **kwargs) def _call_cmd(self, command, stdin=None, stdout=None, stderr=None): if isinstance(command, list): args = [item for sub in command for item in ["-c", sub]] else: args = ["-c", command] return self._call(args, stdin, stdout, stderr) def __call__(self, command, stdouts=None): """ Call a CLI command (e.g. "show running-config") Output text is automatically redirected, decoded and returned. Multiple commands may be passed as list. """ proc = self._call_cmd(command, stdout=subprocess.PIPE) stdout, stderr = proc.communicate() if proc.wait() != 0: if stdouts is not None: stdouts.append(stdout.decode("UTF-8")) raise VtyshException( 'vtysh returned status %d for command "%s"' % (proc.returncode, command) ) return stdout.decode("UTF-8") def is_config_available(self): """ Return False if no frr daemon is running or some other vtysh session is in 'configuration terminal' mode which will prevent us from making any configuration changes. """ output = self("configure") if "VTY configuration is locked by other VTY" in output: log.error("vtysh 'configure' returned\n%s\n" % (output)) return False return True def exec_file(self, filename): child = self._call(["-f", filename]) if child.wait() != 0: raise VtyshException( "vtysh (exec file) exited with status %d" % (child.returncode) ) def mark_file(self, filename, stdin=None): child = self._call( ["-m", "-f", filename], stdout=subprocess.PIPE, stdin=subprocess.PIPE, stderr=subprocess.PIPE, ) try: stdout, stderr = child.communicate() except subprocess.TimeoutExpired: child.kill() stdout, stderr = child.communicate() raise VtyshException("vtysh call timed out!") if child.wait() != 0: raise VtyshException( "vtysh (mark file) exited with status %d:\n%s" % (child.returncode, stderr) ) return stdout.decode("UTF-8") def mark_show_run(self, daemon=None): cmd = "show running-config" if daemon: cmd += " %s" % daemon cmd += " no-header" show_run = self._call_cmd(cmd, stdout=subprocess.PIPE) mark = self._call( ["-m", "-f", "-"], stdin=show_run.stdout, stdout=subprocess.PIPE ) show_run.wait() stdout, stderr = mark.communicate() mark.wait() if show_run.returncode != 0: raise VtyshException( "vtysh (show running-config) exited with status %d:" % (show_run.returncode) ) if mark.returncode != 0: raise VtyshException( "vtysh (mark running-config) exited with status %d" % (mark.returncode) ) return stdout.decode("UTF-8") class Context(object): """ A Context object represents a section of frr configuration such as: ! interface swp3 description swp3 -> r8's swp1 ipv6 nd suppress-ra link-detect ! or a single line context object such as this: ip forwarding """ def __init__(self, keys, lines): self.keys = keys self.lines = lines # Keep a dictionary of the lines, this is to make it easy to tell if a # line exists in this Context self.dlines = OrderedDict() for ligne in lines: self.dlines[ligne] = True def __str__(self): return str(self.keys) + " : " + str(self.lines) def add_lines(self, lines): """ Add lines to specified context """ self.lines.extend(lines) for ligne in lines: self.dlines[ligne] = True def get_normalized_es_id(line): """ The es-id or es-sys-mac need to be converted to lower case """ sub_strs = ["evpn mh es-id", "evpn mh es-sys-mac"] for sub_str in sub_strs: obj = re.match(sub_str + " (?P\S*)", line) if obj: line = "%s %s" % (sub_str, obj.group("esi").lower()) break return line def get_normalized_mac_ip_line(line): if line.startswith("evpn mh es"): return get_normalized_es_id(line) if not "ipv6 add" in line: return get_normalized_ipv6_line(line) return line # This dictionary contains a tree of all commands that we know start a # new multi-line context. All other commands are treated either as # commands inside a multi-line context or as single-line contexts. This # dictionary should be updated whenever a new node is added to FRR. ctx_keywords = { "router bgp ": { "address-family ": { "vni ": {}, }, "vnc defaults": {}, "vnc nve-group ": {}, "vnc l2-group ": {}, "vrf-policy ": {}, "bmp targets ": {}, "segment-routing srv6": {}, }, "router rip": {}, "router ripng": {}, "router isis ": {}, "router openfabric ": {}, "router ospf": {}, "router ospf6": {}, "router eigrp ": {}, "router babel": {}, "mpls ldp": {"address-family ": {"interface ": {}}}, "l2vpn ": {"member pseudowire ": {}}, "key chain ": {"key ": {}}, "vrf ": {}, "interface ": {"link-params": {}}, "pseudowire ": {}, "segment-routing": { "traffic-eng": { "segment-list ": {}, "policy ": {"candidate-path ": {}}, "pcep": {"pcc": {}, "pce ": {}, "pce-config ": {}}, }, "srv6": {"locators": {"locator ": {}}}, }, "nexthop-group ": {}, "route-map ": {}, "pbr-map ": {}, "rpki": {}, "bfd": {"peer ": {}, "profile ": {}}, "line vty": {}, } class Config(object): """ A frr configuration is stored in a Config object. A Config object contains a dictionary of Context objects where the Context keys ('router ospf' for example) are our dictionary key. """ def __init__(self, vtysh): self.lines = [] self.contexts = OrderedDict() self.vtysh = vtysh def load_from_file(self, filename): """ Read configuration from specified file and slurp it into internal memory The internal representation has been marked appropriately by passing it through vtysh with the -m parameter """ log.info("Loading Config object from file %s", filename) file_output = self.vtysh.mark_file(filename) for line in file_output.split("\n"): line = line.strip() # Compress duplicate whitespaces line = " ".join(line.split()) if ":" in line: line = get_normalized_mac_ip_line(line) # vrf static routes can be added in two ways. The old way is: # # "ip route x.x.x.x/x y.y.y.y vrf " # # but it's rendered in the configuration as the new way:: # # vrf # ip route x.x.x.x/x y.y.y.y # exit-vrf # # this difference causes frr-reload to not consider them a # match and delete vrf static routes incorrectly. # fix the old way to match new "show running" output so a # proper match is found. if ( line.startswith("ip route ") or line.startswith("ipv6 route ") ) and " vrf " in line: newline = line.split(" ") vrf_index = newline.index("vrf") vrf_ctx = newline[vrf_index] + " " + newline[vrf_index + 1] del newline[vrf_index : vrf_index + 2] newline = " ".join(newline) self.lines.append(vrf_ctx) self.lines.append(newline) self.lines.append("exit-vrf") line = "end" self.lines.append(line) self.load_contexts() def load_from_show_running(self, daemon): """ Read running configuration and slurp it into internal memory The internal representation has been marked appropriately by passing it through vtysh with the -m parameter """ log.info("Loading Config object from vtysh show running") config_text = self.vtysh.mark_show_run(daemon) for line in config_text.split("\n"): line = line.strip() if ( line == "Building configuration..." or line == "Current configuration:" or not line ): continue self.lines.append(line) self.load_contexts() def get_lines(self): """ Return the lines read in from the configuration """ return "\n".join(self.lines) def get_contexts(self): """ Return the parsed context as strings for display, log etc. """ for _, ctx in sorted(iteritems(self.contexts)): print(str(ctx)) def save_contexts(self, key, lines): """ Save the provided key and lines as a context """ if not key: return # IP addresses specified in "network" statements, "ip prefix-lists" # etc. can differ in the host part of the specification the user # provides and what the running config displays. For example, user can # specify 11.1.1.1/24, and the running config displays this as # 11.1.1.0/24. Ensure we don't do a needless operation for such lines. # IS-IS & OSPFv3 have no "network" support. re_key_rt = re.match(r"(ip|ipv6)\s+route\s+([A-Fa-f:.0-9/]+)(.*)$", key[0]) if re_key_rt: addr = re_key_rt.group(2) if "/" in addr: try: newaddr = ip_network(addr, strict=False) key[0] = "%s route %s/%s%s" % ( re_key_rt.group(1), str(newaddr.network_address), newaddr.prefixlen, re_key_rt.group(3), ) except ValueError: pass re_key_rt = re.match( r"(ip|ipv6)\s+prefix-list(.*)(permit|deny)\s+([A-Fa-f:.0-9/]+)(.*)$", key[0] ) if re_key_rt: addr = re_key_rt.group(4) if "/" in addr: try: network_addr = ip_network(addr, strict=False) newaddr = "%s/%s" % ( str(network_addr.network_address), network_addr.prefixlen, ) except ValueError: newaddr = addr else: newaddr = addr legestr = re_key_rt.group(5) re_lege = re.search(r"(.*)le\s+(\d+)\s+ge\s+(\d+)(.*)", legestr) if re_lege: legestr = "%sge %s le %s%s" % ( re_lege.group(1), re_lege.group(3), re_lege.group(2), re_lege.group(4), ) key[0] = "%s prefix-list%s%s %s%s" % ( re_key_rt.group(1), re_key_rt.group(2), re_key_rt.group(3), newaddr, legestr, ) if lines and key[0].startswith("router bgp"): newlines = [] for line in lines: re_net = re.match(r"network\s+([A-Fa-f:.0-9/]+)(.*)$", line) if re_net: addr = re_net.group(1) if "/" not in addr and key[0].startswith("router bgp"): # This is most likely an error because with no # prefixlen, BGP treats the prefixlen as 8 addr = addr + "/8" try: network_addr = ip_network(addr, strict=False) line = "network %s/%s %s" % ( str(network_addr.network_address), network_addr.prefixlen, re_net.group(2), ) newlines.append(line) except ValueError: # Really this should be an error. Whats a network # without an IP Address following it ? newlines.append(line) else: newlines.append(line) lines = newlines # More fixups in user specification and what running config shows. # "null0" in routes must be replaced by Null0. if ( key[0].startswith("ip route") or key[0].startswith("ipv6 route") and "null0" in key[0] ): key[0] = re.sub(r"\s+null0(\s*$)", " Null0", key[0]) if lines and key[0].startswith("vrf "): newlines = [] for line in lines: if line.startswith("ip route ") or line.startswith("ipv6 route "): if "null0" in line: line = re.sub(r"\s+null0(\s*$)", " Null0", line) newlines.append(line) else: newlines.append(line) lines = newlines if lines: if tuple(key) not in self.contexts: ctx = Context(tuple(key), lines) self.contexts[tuple(key)] = ctx else: ctx = self.contexts[tuple(key)] ctx.add_lines(lines) else: if tuple(key) not in self.contexts: ctx = Context(tuple(key), []) self.contexts[tuple(key)] = ctx def load_contexts(self): """ Parse the configuration and create contexts for each appropriate block The end of a context is flagged via the 'end' keyword: ! interface swp52 ipv6 nd suppress-ra link-detect ! end router bgp 10 bgp router-id 10.0.0.1 bgp log-neighbor-changes no bgp default ipv4-unicast neighbor EBGP peer-group neighbor EBGP advertisement-interval 1 neighbor EBGP timers connect 10 neighbor 2001:40:1:4::6 remote-as 40 neighbor 2001:40:1:8::a remote-as 40 ! end address-family ipv6 neighbor IBGPv6 activate neighbor 2001:10::2 peer-group IBGPv6 neighbor 2001:10::3 peer-group IBGPv6 exit-address-family ! end router ospf ospf router-id 10.0.0.1 log-adjacency-changes detail timers throttle spf 0 50 5000 ! end The code assumes that its working on the output from the "vtysh -m" command. That provides the appropriate markers to signify end of a context. This routine uses that to build the contexts for the config. There are single line contexts such as "log file /media/node/zebra.log" and multi-line contexts such as "router ospf" and subcontexts within a context such as "address-family" within "router bgp" In each of these cases, the first line of the context becomes the key of the context. So "router bgp 10" is the key for the non-address family part of bgp, "router bgp 10, address-family ipv6 unicast" is the key for the subcontext and so on. """ # stack of context keys ctx_keys = [] # stack of context keywords cur_ctx_keywords = [ctx_keywords] # list of stored commands cur_ctx_lines = [] for line in self.lines: if not line: continue if line.startswith("!") or line.startswith("#"): continue if line.startswith("exit"): # ignore on top level if len(ctx_keys) == 0: continue # save current context self.save_contexts(ctx_keys, cur_ctx_lines) # exit current context log.debug("LINE %-50s: exit context %-50s", line, ctx_keys) ctx_keys.pop() cur_ctx_keywords.pop() cur_ctx_lines = [] continue if line.startswith("end"): # exit all contexts while len(ctx_keys) > 0: # save current context self.save_contexts(ctx_keys, cur_ctx_lines) # exit current context log.debug("LINE %-50s: exit context %-50s", line, ctx_keys) ctx_keys.pop() cur_ctx_keywords.pop() cur_ctx_lines = [] continue new_ctx = False # check if the line is a context-entering keyword for k, v in cur_ctx_keywords[-1].items(): if line.startswith(k): # candidate-path is a special case. It may be a node and # may be a single-line command. The distinguisher is the # word "dynamic" or "explicit" at the middle of the line. # It was perhaps not the best choice by the pathd authors # but we have what we have. if k == "candidate-path " and "explicit" in line: # this is a single-line command break # save current context self.save_contexts(ctx_keys, cur_ctx_lines) # enter new context new_ctx = True ctx_keys.append(line) cur_ctx_keywords.append(v) cur_ctx_lines = [] log.debug("LINE %-50s: enter context %-50s", line, ctx_keys) break if new_ctx: continue if len(ctx_keys) == 0: log.debug("LINE %-50s: single-line context", line) self.save_contexts([line], []) else: log.debug("LINE %-50s: add to current context %-50s", line, ctx_keys) cur_ctx_lines.append(line) # Save the context of the last one if len(ctx_keys) > 0: self.save_contexts(ctx_keys, cur_ctx_lines) def lines_to_config(ctx_keys, line, delete): """ Return the command as it would appear in frr.conf """ cmd = [] # If there's no `line` and `ctx_keys` length is 1, then it may be a single-line command. # In this case, we should treat it as a single command in an empty context. if len(ctx_keys) == 1 and not line: single = True for k, v in ctx_keywords.items(): if ctx_keys[0].startswith(k): single = False break if single: line = ctx_keys[0] ctx_keys = [] if line: for i, ctx_key in enumerate(ctx_keys): cmd.append(" " * i + ctx_key) line = line.lstrip() indent = len(ctx_keys) * " " # There are some commands that are on by default so their "no" form will be # displayed in the config. "no bgp default ipv4-unicast" is one of these. # If we need to remove this line we do so by adding "bgp default ipv4-unicast", # not by doing a "no no bgp default ipv4-unicast" if delete: if line.startswith("no "): cmd.append("%s%s" % (indent, line[3:])) else: cmd.append("%sno %s" % (indent, line)) else: cmd.append(indent + line) for i in reversed(range(len(ctx_keys))): cmd.append(" " * i + "exit") # If line is None then we are typically deleting an entire # context ('no router ospf' for example) else: for i, ctx_key in enumerate(ctx_keys[:-1]): cmd.append("%s%s" % (" " * i, ctx_key)) # Only put the 'no' on the last sub-context if delete: if ctx_keys[-1].startswith("no "): cmd.append("%s%s" % (" " * (len(ctx_keys) - 1), ctx_keys[-1][3:])) else: cmd.append("%sno %s" % (" " * (len(ctx_keys) - 1), ctx_keys[-1])) else: cmd.append("%s%s" % (" " * (len(ctx_keys) - 1), ctx_keys[-1])) cmd.append("%sexit" % (" " * (len(ctx_keys) - 1))) for i in reversed(range(len(ctx_keys) - 1)): cmd.append(" " * i + "exit") return cmd def get_normalized_ipv6_line(line): """ Return a normalized IPv6 line as produced by frr, with all letters in lower case and trailing and leading zeros removed, and only the network portion present if the IPv6 word is a network """ norm_line = "" words = line.split(" ") for word in words: if ":" in word: norm_word = None if "/" in word: try: v6word = ip_network(word, strict=False) norm_word = "%s/%s" % ( str(v6word.network_address), v6word.prefixlen, ) except ValueError: pass if not norm_word: try: norm_word = "%s" % IPv6Address(word) except ValueError: norm_word = word else: norm_word = word norm_line = norm_line + " " + norm_word return norm_line.strip() def line_exist(lines, target_ctx_keys, target_line, exact_match=True): for ctx_keys, line in lines: if ctx_keys == target_ctx_keys: if exact_match: if line == target_line: return True else: if line.startswith(target_line): return True return False def bgp_delete_inst_move_line(lines_to_del): # Deletion of bgp default inst followed by # bgp vrf inst leads to issue of default # instance can not be removed. # Move the bgp default instance line to end. bgp_defult_inst = False bgp_vrf_inst = False for ctx_keys, line in lines_to_del: # Find bgp default inst if ( ctx_keys[0].startswith("router bgp") and not line and "vrf" not in ctx_keys[0] ): bgp_defult_inst = True # Find bgp vrf inst if ctx_keys[0].startswith("router bgp") and not line and "vrf" in ctx_keys[0]: bgp_vrf_inst = True if bgp_defult_inst and bgp_vrf_inst: for ctx_keys, line in lines_to_del: # move bgp default inst to end if ( ctx_keys[0].startswith("router bgp") and not line and "vrf" not in ctx_keys[0] ): lines_to_del.remove((ctx_keys, line)) lines_to_del.append((ctx_keys, line)) def bgp_delete_nbr_remote_as_line(lines_to_add): # Handle deletion of neighbor remote-as line from # lines_to_add if the nbr is configured with peer-group and # peer-group has remote-as config present. # 'neighbor remote-as change on peer is not allowed # if the peer is part of peer-group and peer-group has # remote-as config. pg_dict = dict() found_pg_cmd = False # Find all peer-group commands; create dict of each peer-group # to store assoicated neighbor as value for ctx_keys, line in lines_to_add: if ( ctx_keys[0].startswith("router bgp") and line and line.startswith("neighbor ") ): # {'router bgp 65001': {'PG': [], 'PG1': []}, # 'router bgp 65001 vrf vrf1': {'PG': [], 'PG1': []}} if ctx_keys[0] not in pg_dict: pg_dict[ctx_keys[0]] = dict() # find 'neighbor peer-group' re_pg = re.match("neighbor (\S+) peer-group$", line) if re_pg and re_pg.group(1) not in pg_dict[ctx_keys[0]]: pg_dict[ctx_keys[0]][re_pg.group(1)] = { "nbr": list(), "remoteas": False, } found_pg_cmd = True # Do nothing if there is no any "peer-group" if found_pg_cmd is False: return # Find peer-group with remote-as command, also search neighbor # associated to peer-group and store into peer-group dict for ctx_keys, line in lines_to_add: if ( ctx_keys[0].startswith("router bgp") and line and line.startswith("neighbor ") ): if ctx_keys[0] in pg_dict: for pg_key in pg_dict[ctx_keys[0]]: # Find 'neighbor remote-as' pg_rmtas = "neighbor %s remote-as (\S+)" % pg_key re_pg_rmtas = re.search(pg_rmtas, line) if re_pg_rmtas: pg_dict[ctx_keys[0]][pg_key]["remoteas"] = True # Find 'neighbor [interface] peer-group ' nb_pg = "neighbor (\S+) peer-group %s$" % pg_key re_nbr_pg = re.search(nb_pg, line) if ( re_nbr_pg and re_nbr_pg.group(1) not in pg_dict[ctx_keys[0]][pg_key] ): pg_dict[ctx_keys[0]][pg_key]["nbr"].append(re_nbr_pg.group(1)) # Find any neighbor remote-as config line check if the nbr # is in the peer group's list of nbrs. Remove 'neighbor remote-as <>' # from lines_to_add. lines_to_del_from_add = [] for ctx_keys, line in lines_to_add: if ( ctx_keys[0].startswith("router bgp") and line and line.startswith("neighbor ") ): nbr_rmtas = "neighbor (\S+) remote-as.*" re_nbr_rmtas = re.search(nbr_rmtas, line) if re_nbr_rmtas and ctx_keys[0] in pg_dict: for pg in pg_dict[ctx_keys[0]]: if pg_dict[ctx_keys[0]][pg]["remoteas"] == True: for nbr in pg_dict[ctx_keys[0]][pg]["nbr"]: if re_nbr_rmtas.group(1) == nbr: lines_to_del_from_add.append((ctx_keys, line)) for ctx_keys, line in lines_to_del_from_add: lines_to_add.remove((ctx_keys, line)) def bgp_remove_neighbor_cfg(lines_to_del, del_nbr_dict): # This method handles deletion of bgp neighbor configs, # if there is neighbor to peer-group cmd is in delete list. # As 'no neighbor .* peer-group' deletes the neighbor, # subsequent neighbor speciic config line deletion results # in error. lines_to_del_to_del = [] for ctx_keys, line in lines_to_del: if ( ctx_keys[0].startswith("router bgp") and line and line.startswith("neighbor ") ): if ctx_keys[0] in del_nbr_dict: for nbr in del_nbr_dict[ctx_keys[0]]: re_nbr_pg = re.search("neighbor (\S+) .*peer-group (\S+)", line) nb_exp = "neighbor %s .*" % nbr if not re_nbr_pg: re_nb = re.search(nb_exp, line) if re_nb: lines_to_del_to_del.append((ctx_keys, line)) for ctx_keys, line in lines_to_del_to_del: lines_to_del.remove((ctx_keys, line)) def bgp_delete_move_lines(lines_to_add, lines_to_del): # This method handles deletion of bgp peer group config. # The objective is to delete config lines related to peers # associated with the peer-group and move the peer-group # config line to the end of the lines_to_del list. bgp_delete_nbr_remote_as_line(lines_to_add) del_dict = dict() del_nbr_dict = dict() # Stores the lines to move to the end of the pending list. lines_to_del_to_del = [] # Stores the lines to move to end of the pending list. lines_to_del_to_app = [] found_pg_del_cmd = False # When "neighbor peer-group" under a bgp instance is removed, # it also deletes the associated peer config. Any config line below no form of # peer-group related to a peer are errored out as the peer no longer exists. # To cleanup peer-group and associated peer(s) configs: # - Remove all the peers config lines from the pending list (lines_to_del list). # - Move peer-group deletion line to the end of the pending list, to allow # removal of any of the peer-group specific configs. # # Create a dictionary of config context (i.e. router bgp vrf x). # Under each context node, create a dictionary of a peer-group name. # Append a peer associated to the peer-group into a list under a peer-group node. # Remove all of the peer associated config lines from the pending list. # Append peer-group deletion line to end of the pending list. # # Example: # neighbor underlay peer-group # neighbor underlay remote-as external # neighbor underlay advertisement-interval 0 # neighbor underlay timers 3 9 # neighbor underlay timers connect 10 # neighbor swp1 interface peer-group underlay # neighbor swp1 advertisement-interval 0 # neighbor swp1 timers 3 9 # neighbor swp1 timers connect 10 # neighbor swp2 interface peer-group underlay # neighbor swp2 advertisement-interval 0 # neighbor swp2 timers 3 9 # neighbor swp2 timers connect 10 # neighbor swp3 interface peer-group underlay # neighbor uplink1 interface remote-as internal # neighbor uplink1 advertisement-interval 0 # neighbor uplink1 timers 3 9 # neighbor uplink1 timers connect 10 # New order: # "router bgp 200 no bgp bestpath as-path multipath-relax" # "router bgp 200 no neighbor underlay advertisement-interval 0" # "router bgp 200 no neighbor underlay timers 3 9" # "router bgp 200 no neighbor underlay timers connect 10" # "router bgp 200 no neighbor uplink1 advertisement-interval 0" # "router bgp 200 no neighbor uplink1 timers 3 9" # "router bgp 200 no neighbor uplink1 timers connect 10" # "router bgp 200 no neighbor underlay remote-as external" # "router bgp 200 no neighbor uplink1 interface remote-as internal" # "router bgp 200 no neighbor underlay peer-group" for ctx_keys, line in lines_to_del: if ( ctx_keys[0].startswith("router bgp") and line and line.startswith("neighbor ") ): # When 'neighbor remote-as <>' is removed it deletes the peer, # there might be a peer associated config which also needs to be removed # prior to peer. # Append the 'neighbor remote-as <>' to the lines_to_del. # Example: # # neighbor uplink1 interface remote-as internal # neighbor uplink1 advertisement-interval 0 # neighbor uplink1 timers 3 9 # neighbor uplink1 timers connect 10 # Move to end: # neighbor uplink1 advertisement-interval 0 # neighbor uplink1 timers 3 9 # neighbor uplink1 timers connect 10 # ... # # neighbor uplink1 interface remote-as internal # # 'no neighbor peer [interface] remote-as <>' nb_remoteas = "neighbor (\S+) .*remote-as (\S+)" re_nb_remoteas = re.search(nb_remoteas, line) if re_nb_remoteas: lines_to_del_to_app.append((ctx_keys, line)) # 'no neighbor peer [interface] peer-group <>' is in lines_to_del # copy the neighbor and look for all config removal lines associated # to neighbor and delete them from the lines_to_del re_nbr_pg = re.search("neighbor (\S+) .*peer-group (\S+)", line) if re_nbr_pg: if ctx_keys[0] not in del_nbr_dict: del_nbr_dict[ctx_keys[0]] = list() if re_nbr_pg.group(1) not in del_nbr_dict[ctx_keys[0]]: del_nbr_dict[ctx_keys[0]].append(re_nbr_pg.group(1)) # {'router bgp 65001': {'PG': [], 'PG1': []}, # 'router bgp 65001 vrf vrf1': {'PG': [], 'PG1': []}} if ctx_keys[0] not in del_dict: del_dict[ctx_keys[0]] = dict() # find 'no neighbor peer-group' re_pg = re.match("neighbor (\S+) peer-group$", line) if re_pg and re_pg.group(1) not in del_dict[ctx_keys[0]]: del_dict[ctx_keys[0]][re_pg.group(1)] = list() found_pg_del_cmd = True if found_pg_del_cmd == False: bgp_delete_inst_move_line(lines_to_del) if del_nbr_dict: bgp_remove_neighbor_cfg(lines_to_del, del_nbr_dict) return (lines_to_add, lines_to_del) for ctx_keys, line in lines_to_del_to_app: lines_to_del.remove((ctx_keys, line)) lines_to_del.append((ctx_keys, line)) # {'router bgp 65001': {'PG': ['10.1.1.2'], 'PG1': ['10.1.1.21']}, # 'router bgp 65001 vrf vrf1': {'PG': ['10.1.1.2'], 'PG1': ['10.1.1.21']}} for ctx_keys, line in lines_to_del: if ( ctx_keys[0].startswith("router bgp") and line and line.startswith("neighbor ") ): if ctx_keys[0] in del_dict: for pg_key in del_dict[ctx_keys[0]]: # 'neighbor [interface] peer-group ' nb_pg = "neighbor (\S+) .*peer-group %s$" % pg_key re_nbr_pg = re.search(nb_pg, line) if ( re_nbr_pg and re_nbr_pg.group(1) not in del_dict[ctx_keys[0]][pg_key] ): del_dict[ctx_keys[0]][pg_key].append(re_nbr_pg.group(1)) lines_to_del_to_app = [] for ctx_keys, line in lines_to_del: if ( ctx_keys[0].startswith("router bgp") and line and line.startswith("neighbor ") ): if ctx_keys[0] in del_dict: for pg in del_dict[ctx_keys[0]]: for nbr in del_dict[ctx_keys[0]][pg]: nb_exp = "neighbor %s .*" % nbr re_nb = re.search(nb_exp, line) # add peer configs to delete list. if re_nb and line not in lines_to_del_to_del: lines_to_del_to_del.append((ctx_keys, line)) pg_exp = "neighbor %s peer-group$" % pg re_pg = re.match(pg_exp, line) if re_pg: lines_to_del_to_app.append((ctx_keys, line)) for ctx_keys, line in lines_to_del_to_del: lines_to_del.remove((ctx_keys, line)) for ctx_keys, line in lines_to_del_to_app: lines_to_del.remove((ctx_keys, line)) lines_to_del.append((ctx_keys, line)) bgp_delete_inst_move_line(lines_to_del) return (lines_to_add, lines_to_del) def pim_delete_move_lines(lines_to_add, lines_to_del): # Under interface context, if 'no ip pim' is present # remove subsequent 'no ip pim ' options as it # they are implicitly deleted by 'no ip pim'. # Remove all such depdendent options from delete # pending list. pim_disable = False for ctx_keys, line in lines_to_del: if ctx_keys[0].startswith("interface") and line and line == "ip pim": pim_disable = True if pim_disable: for ctx_keys, line in lines_to_del: if ( ctx_keys[0].startswith("interface") and line and line.startswith("ip pim ") ): lines_to_del.remove((ctx_keys, line)) return (lines_to_add, lines_to_del) def delete_move_lines(lines_to_add, lines_to_del): lines_to_add, lines_to_del = bgp_delete_move_lines(lines_to_add, lines_to_del) lines_to_add, lines_to_del = pim_delete_move_lines(lines_to_add, lines_to_del) return (lines_to_add, lines_to_del) def ignore_delete_re_add_lines(lines_to_add, lines_to_del): # Quite possibly the most confusing (while accurate) variable names in history lines_to_add_to_del = [] lines_to_del_to_del = [] index = -1 for ctx_keys, line in lines_to_del: deleted = False # no form of route-map description command only # accept 'no description', replace 'no description blah' # to just 'no description'. index = index + 1 if ( ctx_keys[0].startswith("route-map") and line and line.startswith("description ") ): lines_to_del.remove((ctx_keys, line)) lines_to_del.insert(index, (ctx_keys, "description")) # interface x ; description blah # no form of description does not accept any argument, # strip arg before rendering if ( ctx_keys[0].startswith("interface ") and line and line.startswith("description ") ): lines_to_del.remove((ctx_keys, line)) lines_to_del.insert(index, (ctx_keys, "description")) # If there is a change in the segment routing block ranges, do it # in-place, to avoid requesting spurious label chunks which might fail if line and "segment-routing global-block" in line: for add_key, add_line in lines_to_add: if ( ctx_keys[0] == add_key[0] and add_line and "segment-routing global-block" in add_line ): lines_to_del_to_del.append((ctx_keys, line)) break continue if ctx_keys[0].startswith("router bgp") and line: if line.startswith("neighbor "): # BGP changed how it displays swpX peers that are part of peer-group. Older # versions of frr would display these on separate lines: # neighbor swp1 interface # neighbor swp1 peer-group FOO # # but today we display via a single line # neighbor swp1 interface peer-group FOO # # This change confuses frr-reload.py so check to see if we are deleting # neighbor swp1 interface peer-group FOO # # and adding # neighbor swp1 interface # neighbor swp1 peer-group FOO # # If so then chop the del line and the corresponding add lines re_swpx_int_peergroup = re.search( "neighbor (\S+) interface peer-group (\S+)", line ) re_swpx_int_v6only_peergroup = re.search( "neighbor (\S+) interface v6only peer-group (\S+)", line ) if re_swpx_int_peergroup or re_swpx_int_v6only_peergroup: swpx_interface = None swpx_peergroup = None if re_swpx_int_peergroup: swpx = re_swpx_int_peergroup.group(1) peergroup = re_swpx_int_peergroup.group(2) swpx_interface = "neighbor %s interface" % swpx elif re_swpx_int_v6only_peergroup: swpx = re_swpx_int_v6only_peergroup.group(1) peergroup = re_swpx_int_v6only_peergroup.group(2) swpx_interface = "neighbor %s interface v6only" % swpx swpx_peergroup = "neighbor %s peer-group %s" % (swpx, peergroup) found_add_swpx_interface = line_exist( lines_to_add, ctx_keys, swpx_interface ) found_add_swpx_peergroup = line_exist( lines_to_add, ctx_keys, swpx_peergroup ) tmp_ctx_keys = tuple(list(ctx_keys)) if not found_add_swpx_peergroup: tmp_ctx_keys = list(ctx_keys) tmp_ctx_keys.append("address-family ipv4 unicast") tmp_ctx_keys = tuple(tmp_ctx_keys) found_add_swpx_peergroup = line_exist( lines_to_add, tmp_ctx_keys, swpx_peergroup ) if not found_add_swpx_peergroup: tmp_ctx_keys = list(ctx_keys) tmp_ctx_keys.append("address-family ipv6 unicast") tmp_ctx_keys = tuple(tmp_ctx_keys) found_add_swpx_peergroup = line_exist( lines_to_add, tmp_ctx_keys, swpx_peergroup ) if found_add_swpx_interface and found_add_swpx_peergroup: deleted = True lines_to_del_to_del.append((ctx_keys, line)) lines_to_add_to_del.append((ctx_keys, swpx_interface)) lines_to_add_to_del.append((tmp_ctx_keys, swpx_peergroup)) # Changing the bfd timers on neighbors is allowed without doing # a delete/add process. Since doing a "no neighbor blah bfd # ..." will cause the peer to bounce unnecessarily, just skip # the delete and just do the add. re_nbr_bfd_timers = re.search( r"neighbor (\S+) bfd (\S+) (\S+) (\S+)", line ) if re_nbr_bfd_timers: nbr = re_nbr_bfd_timers.group(1) bfd_nbr = "neighbor %s" % nbr bfd_search_string = bfd_nbr + r" bfd (\S+) (\S+) (\S+)" for ctx_keys, add_line in lines_to_add: if ctx_keys[0].startswith("router bgp"): re_add_nbr_bfd_timers = re.search( bfd_search_string, add_line ) if re_add_nbr_bfd_timers: found_add_bfd_nbr = line_exist( lines_to_add, ctx_keys, bfd_nbr, False ) if found_add_bfd_nbr: lines_to_del_to_del.append((ctx_keys, line)) # Neighbor changes of route-maps need to be accounted for in # that we do not want to do a `no route-map...` `route-map # ....` when changing a route-map. This is bad mojo as that we # will send/receive data we don't want. Additionally we need # to ensure that if we have different afi/safi variants that # they actually match and if we are going from a very old style # command such that the neighbor command is under the `router # bgp ..` node that we need to handle that appropriately re_nbr_rm = re.search("neighbor(.*)route-map(.*)(in|out)$", line) if re_nbr_rm: adjust_for_bgp_node = 0 neighbor_name = re_nbr_rm.group(1) rm_name_del = re_nbr_rm.group(2) dir = re_nbr_rm.group(3) search = "neighbor%sroute-map(.*)%s" % (neighbor_name, dir) save_line = "EMPTY" for ctx_keys_al, add_line in lines_to_add: if ctx_keys_al[0].startswith("router bgp"): if add_line: rm_match = re.search(search, add_line) if rm_match: rm_name_add = rm_match.group(1) if rm_name_add == rm_name_del: continue if len(ctx_keys_al) == 1: save_line = line adjust_for_bgp_node = 1 else: if ( len(ctx_keys) > 1 and len(ctx_keys_al) > 1 and ctx_keys[1] == ctx_keys_al[1] ): lines_to_del_to_del.append((ctx_keys_al, line)) if adjust_for_bgp_node == 1: for ctx_keys_dl, dl_line in lines_to_del: if ( ctx_keys_dl[0].startswith("router bgp") and len(ctx_keys_dl) > 1 and ctx_keys_dl[1] == "address-family ipv4 unicast" ): if save_line == dl_line: lines_to_del_to_del.append((ctx_keys_dl, save_line)) # We changed how we display the neighbor interface command. Older # versions of frr would display the following: # neighbor swp1 interface # neighbor swp1 remote-as external # neighbor swp1 capability extended-nexthop # # but today we display via a single line # neighbor swp1 interface remote-as external # # and capability extended-nexthop is no longer needed because we # automatically enable it when the neighbor is of type interface. # # This change confuses frr-reload.py so check to see if we are deleting # neighbor swp1 interface remote-as (external|internal|ASNUM) # # and adding # neighbor swp1 interface # neighbor swp1 remote-as (external|internal|ASNUM) # neighbor swp1 capability extended-nexthop # # If so then chop the del line and the corresponding add lines re_swpx_int_remoteas = re.search( "neighbor (\S+) interface remote-as (\S+)", line ) re_swpx_int_v6only_remoteas = re.search( "neighbor (\S+) interface v6only remote-as (\S+)", line ) if re_swpx_int_remoteas or re_swpx_int_v6only_remoteas: swpx_interface = None swpx_remoteas = None if re_swpx_int_remoteas: swpx = re_swpx_int_remoteas.group(1) remoteas = re_swpx_int_remoteas.group(2) swpx_interface = "neighbor %s interface" % swpx elif re_swpx_int_v6only_remoteas: swpx = re_swpx_int_v6only_remoteas.group(1) remoteas = re_swpx_int_v6only_remoteas.group(2) swpx_interface = "neighbor %s interface v6only" % swpx swpx_remoteas = "neighbor %s remote-as %s" % (swpx, remoteas) found_add_swpx_interface = line_exist( lines_to_add, ctx_keys, swpx_interface ) found_add_swpx_remoteas = line_exist( lines_to_add, ctx_keys, swpx_remoteas ) tmp_ctx_keys = tuple(list(ctx_keys)) if found_add_swpx_interface and found_add_swpx_remoteas: deleted = True lines_to_del_to_del.append((ctx_keys, line)) lines_to_add_to_del.append((ctx_keys, swpx_interface)) lines_to_add_to_del.append((tmp_ctx_keys, swpx_remoteas)) # We made the 'bgp bestpath as-path multipath-relax' command # automatically assume 'no-as-set' since the lack of this option # caused weird routing problems. When the running config is shown # in releases with this change, the no-as-set keyword is not shown # as it is the default. This causes frr-reload to unnecessarily # unapply this option only to apply it back again, causing # unnecessary session resets. if "multipath-relax" in line: re_asrelax_new = re.search( "^bgp\s+bestpath\s+as-path\s+multipath-relax$", line ) old_asrelax_cmd = "bgp bestpath as-path multipath-relax no-as-set" found_asrelax_old = line_exist(lines_to_add, ctx_keys, old_asrelax_cmd) if re_asrelax_new and found_asrelax_old: deleted = True lines_to_del_to_del.append((ctx_keys, line)) lines_to_add_to_del.append((ctx_keys, old_asrelax_cmd)) # If we are modifying the BGP table-map we need to avoid a del/add # and instead modify the table-map in place via an add. This is # needed to avoid installing all routes in the RIB the second the # 'no table-map' is issued. if line.startswith("table-map"): found_table_map = line_exist(lines_to_add, ctx_keys, "table-map", False) if found_table_map: lines_to_del_to_del.append((ctx_keys, line)) # More old-to-new config handling. ip import-table no longer accepts # distance, but we honor the old syntax. But 'show running' shows only # the new syntax. This causes an unnecessary 'no import-table' followed # by the same old 'ip import-table' which causes perturbations in # announced routes leading to traffic blackholes. Fix this issue. re_importtbl = re.search("^ip\s+import-table\s+(\d+)$", ctx_keys[0]) if re_importtbl: table_num = re_importtbl.group(1) for ctx in lines_to_add: if ctx[0][0].startswith("ip import-table %s distance" % table_num): lines_to_del_to_del.append( (("ip import-table %s" % table_num,), None) ) lines_to_add_to_del.append((ctx[0], None)) # ip/ipv6 prefix-lists and access-lists can be specified without a seq # number. However, the running config always adds 'seq x', where x is # a number incremented by 5 for every element of the prefix/access # list. So, ignore such lines as well. Sample prefix-list and # acces-list lines: # ip prefix-list PR-TABLE-2 seq 5 permit 20.8.2.0/24 le 32 # ip prefix-list PR-TABLE-2 seq 10 permit 20.8.2.0/24 le 32 # ipv6 prefix-list vrfdev6-12 permit 2000:9:2::/64 gt 64 # access-list FOO seq 5 permit 2.2.2.2/32 # ipv6 access-list BAR seq 5 permit 2:2:2::2/128 re_acl_pfxlst = re.search( "^(ip |ipv6 |)(prefix-list|access-list)(\s+\S+\s+)(seq \d+\s+)(permit|deny)(.*)$", ctx_keys[0], ) if re_acl_pfxlst: found = False tmpline = ( re_acl_pfxlst.group(1) + re_acl_pfxlst.group(2) + re_acl_pfxlst.group(3) + re_acl_pfxlst.group(5) + re_acl_pfxlst.group(6) ) for ctx in lines_to_add: if ctx[0][0] == tmpline: lines_to_del_to_del.append((ctx_keys, None)) lines_to_add_to_del.append(((tmpline,), None)) found = True # If prefix-lists or access-lists are being deleted and not added # (see comment above), add command with 'no' to lines_to_add and # remove from lines_to_del to improve scaling performance. if found is False: add_cmd = ("no " + ctx_keys[0],) lines_to_add.append((add_cmd, None)) lines_to_del_to_del.append((ctx_keys, None)) # bgp community-list, large-community-list, extcommunity-list can be # specified without a seq number. However, the running config always # adds `seq X` (sequence number). So, ignore such lines as well. # Examples: # bgp community-list standard clist seq 5 permit 222:213 # bgp large-community-list standard llist seq 5 permit 65001:65001:1 # bgp extcommunity-list standard elist seq 5 permit soo 123:123 re_bgp_lists = re.search( "^(bgp )(community-list|large-community-list|extcommunity-list)(\s+\S+\s+)(\S+\s+)(seq \d+\s+)(permit|deny)(.*)$", ctx_keys[0], ) if re_bgp_lists: found = False tmpline = ( re_bgp_lists.group(1) + re_bgp_lists.group(2) + re_bgp_lists.group(3) + re_bgp_lists.group(4) + re_bgp_lists.group(6) + re_bgp_lists.group(7) ) for ctx in lines_to_add: if ctx[0][0] == tmpline: lines_to_del_to_del.append((ctx_keys, None)) lines_to_add_to_del.append(((tmpline,), None)) found = True if found is False: add_cmd = ("no " + ctx_keys[0],) lines_to_add.append((add_cmd, None)) lines_to_del_to_del.append((ctx_keys, None)) if ( len(ctx_keys) == 3 and ctx_keys[0].startswith("router bgp") and ctx_keys[1] == "address-family l2vpn evpn" and ctx_keys[2].startswith("vni") ): re_route_target = ( re.search("^route-target import (.*)$", line) if line is not None else False ) if re_route_target: rt = re_route_target.group(1).strip() route_target_import_line = line route_target_export_line = "route-target export %s" % rt route_target_both_line = "route-target both %s" % rt found_route_target_export_line = line_exist( lines_to_del, ctx_keys, route_target_export_line ) found_route_target_both_line = line_exist( lines_to_add, ctx_keys, route_target_both_line ) # If the running configs has # route-target import 1:1 # route-target export 1:1 # and the config we are reloading against has # route-target both 1:1 # then we can ignore deleting the import/export and ignore adding the 'both' if found_route_target_export_line and found_route_target_both_line: lines_to_del_to_del.append((ctx_keys, route_target_import_line)) lines_to_del_to_del.append((ctx_keys, route_target_export_line)) lines_to_add_to_del.append((ctx_keys, route_target_both_line)) # Deleting static routes under a vrf can lead to time-outs if each is sent # as separate vtysh -c commands. Change them from being in lines_to_del and # put the "no" form in lines_to_add if ctx_keys[0].startswith("vrf ") and line: if line.startswith("ip route") or line.startswith("ipv6 route"): add_cmd = "no " + line lines_to_add.append((ctx_keys, add_cmd)) lines_to_del_to_del.append((ctx_keys, line)) if not deleted: found_add_line = line_exist(lines_to_add, ctx_keys, line) if found_add_line: lines_to_del_to_del.append((ctx_keys, line)) lines_to_add_to_del.append((ctx_keys, line)) else: # We have commands that used to be displayed in the global part # of 'router bgp' that are now displayed under 'address-family ipv4 unicast' # # # old way # router bgp 64900 # neighbor ISL advertisement-interval 0 # # vs. # # # new way # router bgp 64900 # address-family ipv4 unicast # neighbor ISL advertisement-interval 0 # # Look to see if we are deleting it in one format just to add it back in the other if ( ctx_keys[0].startswith("router bgp") and len(ctx_keys) > 1 and ctx_keys[1] == "address-family ipv4 unicast" ): tmp_ctx_keys = list(ctx_keys)[:-1] tmp_ctx_keys = tuple(tmp_ctx_keys) found_add_line = line_exist(lines_to_add, tmp_ctx_keys, line) if found_add_line: lines_to_del_to_del.append((ctx_keys, line)) lines_to_add_to_del.append((tmp_ctx_keys, line)) for ctx_keys, line in lines_to_del_to_del: try: lines_to_del.remove((ctx_keys, line)) except ValueError: pass for ctx_keys, line in lines_to_add_to_del: try: lines_to_add.remove((ctx_keys, line)) except ValueError: pass return (lines_to_add, lines_to_del) def ignore_unconfigurable_lines(lines_to_add, lines_to_del): """ There are certain commands that cannot be removed. Remove those commands from lines_to_del. """ lines_to_del_to_del = [] for ctx_keys, line in lines_to_del: # The integrated-vtysh-config one is technically "no"able but if we did # so frr-reload would stop working so do not let the user shoot # themselves in the foot by removing this. if any( [ ctx_keys[0].startswith(x) for x in [ "agentx", "frr version", "frr defaults", "username", "password", "line vty", "service integrated-vtysh-config", ] ] ): log.info('"%s" cannot be removed' % (ctx_keys[-1],)) lines_to_del_to_del.append((ctx_keys, line)) for ctx_keys, line in lines_to_del_to_del: lines_to_del.remove((ctx_keys, line)) return (lines_to_add, lines_to_del) def compare_context_objects(newconf, running): """ Create a context diff for the two specified contexts """ # Compare the two Config objects to find the lines that we need to add/del lines_to_add = [] lines_to_del = [] pollist_to_del = [] seglist_to_del = [] pceconf_to_del = [] pcclist_to_del = [] candidates_to_add = [] delete_bgpd = False area_stub_no_sum = "area (\S+) stub no-summary" deleted_keychains = [] # Find contexts that are in newconf but not in running # Find contexts that are in running but not in newconf for running_ctx_keys, running_ctx in iteritems(running.contexts): if running_ctx_keys in newconf.contexts: newconf_ctx = newconf.contexts[running_ctx_keys] for line in running_ctx.lines: # ospf area <> stub no-summary line removal requires # to remoe area <> stub as no form of original # retains the stub form. # lines_to_del will contain: # no area stub no-summary and # no area stub if ( running_ctx_keys[0].startswith("router ospf") and line not in newconf_ctx.dlines ): re_area_stub_no_sum = re.search(area_stub_no_sum, line) if re_area_stub_no_sum: new_del_line = "area %s stub" % re_area_stub_no_sum.group(1) lines_to_del.append((running_ctx_keys, new_del_line)) if running_ctx_keys not in newconf.contexts: # We check that the len is 1 here so that we only look at ('router bgp 10') # and not ('router bgp 10', 'address-family ipv4 unicast'). The # latter could cause a false delete_bgpd positive if ipv4 unicast is in # running but not in newconf. if "router bgp" in running_ctx_keys[0] and len(running_ctx_keys) == 1: delete_bgpd = True lines_to_del.append((running_ctx_keys, None)) # We cannot do 'no interface' or 'no vrf' in FRR, and so deal with it elif running_ctx_keys[0].startswith("interface") or running_ctx_keys[ 0 ].startswith("vrf"): for line in running_ctx.lines: lines_to_del.append((running_ctx_keys, line)) # If this is an address-family under 'router bgp' and we are already deleting the # entire 'router bgp' context then ignore this sub-context elif ( "router bgp" in running_ctx_keys[0] and len(running_ctx_keys) > 1 and delete_bgpd ): continue # Check if key chain is being deleted: # - If it is being deleted then avoid deleting its contexts # - Else delete its configuration without removing the root node elif ( running_ctx_keys[0].startswith("key chain ") and len(running_ctx_keys) == 1 ): deleted_keychains.append(running_ctx_keys[0]) lines_to_del.append((running_ctx_keys, None)) elif ( running_ctx_keys[0].startswith("key chain ") and len(running_ctx_keys) > 1 and running_ctx_keys[0] in deleted_keychains ): continue # Delete an entire vni sub-context under "address-family l2vpn evpn" elif ( "router bgp" in running_ctx_keys[0] and len(running_ctx_keys) > 2 and running_ctx_keys[1].startswith("address-family l2vpn evpn") and running_ctx_keys[2].startswith("vni ") ): lines_to_del.append((running_ctx_keys, None)) elif ( "router bgp" in running_ctx_keys[0] and len(running_ctx_keys) > 1 and running_ctx_keys[1].startswith("address-family") ): # There's no 'no address-family' support and so we have to # delete each line individually again for line in running_ctx.lines: lines_to_del.append((running_ctx_keys, line)) # Some commands can happen at higher counts that make # doing vtysh -c inefficient (and can time out.) For # these commands, instead of adding them to lines_to_del, # add the "no " version to lines_to_add. elif running_ctx_keys[0].startswith("ip route") or running_ctx_keys[ 0 ].startswith("ipv6 route"): add_cmd = ("no " + running_ctx_keys[0],) lines_to_add.append((add_cmd, None)) # if this an interface sub-subcontext in an address-family block in ldpd and # we are already deleting the whole context, then ignore this elif ( len(running_ctx_keys) > 2 and running_ctx_keys[0].startswith("mpls ldp") and running_ctx_keys[1].startswith("address-family") and (running_ctx_keys[:2], None) in lines_to_del ): continue # same thing for a pseudowire sub-context inside an l2vpn context elif ( len(running_ctx_keys) > 1 and running_ctx_keys[0].startswith("l2vpn") and running_ctx_keys[1].startswith("member pseudowire") and (running_ctx_keys[:1], None) in lines_to_del ): continue # Segment routing and traffic engineering never need to be deleted elif ( running_ctx_keys[0].startswith("segment-routing") and len(running_ctx_keys) < 3 ): continue # Neither the pcep command elif ( len(running_ctx_keys) == 3 and running_ctx_keys[0].startswith("segment-routing") and running_ctx_keys[2].startswith("pcep") ): continue # Segment lists can only be deleted after we removed all the candidate paths that # use them, so add them to a separate array that is going to be appended at the end elif ( len(running_ctx_keys) == 3 and running_ctx_keys[0].startswith("segment-routing") and running_ctx_keys[2].startswith("segment-list") ): seglist_to_del.append((running_ctx_keys, None)) # Policies must be deleted after there candidate path, to be sure # we add them to a separate array that is going to be appended at the end elif ( len(running_ctx_keys) == 3 and running_ctx_keys[0].startswith("segment-routing") and running_ctx_keys[2].startswith("policy") ): pollist_to_del.append((running_ctx_keys, None)) # pce-config must be deleted after the pce, to be sure we add them # to a separate array that is going to be appended at the end elif ( len(running_ctx_keys) >= 4 and running_ctx_keys[0].startswith("segment-routing") and running_ctx_keys[3].startswith("pce-config") ): pceconf_to_del.append((running_ctx_keys, None)) # pcc must be deleted after the pce and pce-config too elif ( len(running_ctx_keys) >= 4 and running_ctx_keys[0].startswith("segment-routing") and running_ctx_keys[3].startswith("pcc") ): pcclist_to_del.append((running_ctx_keys, None)) # Non-global context elif running_ctx_keys and not any( "address-family" in key for key in running_ctx_keys ): lines_to_del.append((running_ctx_keys, None)) elif running_ctx_keys and not any("vni" in key for key in running_ctx_keys): lines_to_del.append((running_ctx_keys, None)) # Global context else: for line in running_ctx.lines: lines_to_del.append((running_ctx_keys, line)) # if we have some policies commands to delete, append them to lines_to_del if len(pollist_to_del) > 0: lines_to_del.extend(pollist_to_del) # if we have some segment list commands to delete, append them to lines_to_del if len(seglist_to_del) > 0: lines_to_del.extend(seglist_to_del) # if we have some pce list commands to delete, append them to lines_to_del if len(pceconf_to_del) > 0: lines_to_del.extend(pceconf_to_del) # if we have some pcc list commands to delete, append them to lines_to_del if len(pcclist_to_del) > 0: lines_to_del.extend(pcclist_to_del) # Find the lines within each context to add # Find the lines within each context to del for newconf_ctx_keys, newconf_ctx in iteritems(newconf.contexts): if newconf_ctx_keys in running.contexts: running_ctx = running.contexts[newconf_ctx_keys] for line in newconf_ctx.lines: if line not in running_ctx.dlines: # candidate paths can only be added after the policy and segment list, # so add them to a separate array that is going to be appended at the end if ( len(newconf_ctx_keys) == 3 and newconf_ctx_keys[0].startswith("segment-routing") and newconf_ctx_keys[2].startswith("policy ") and line.startswith("candidate-path ") ): candidates_to_add.append((newconf_ctx_keys, line)) else: lines_to_add.append((newconf_ctx_keys, line)) for line in running_ctx.lines: if line not in newconf_ctx.dlines: lines_to_del.append((newconf_ctx_keys, line)) for newconf_ctx_keys, newconf_ctx in iteritems(newconf.contexts): if newconf_ctx_keys not in running.contexts: # candidate paths can only be added after the policy and segment list, # so add them to a separate array that is going to be appended at the end if ( len(newconf_ctx_keys) == 4 and newconf_ctx_keys[0].startswith("segment-routing") and newconf_ctx_keys[3].startswith("candidate-path") ): candidates_to_add.append((newconf_ctx_keys, None)) for line in newconf_ctx.lines: candidates_to_add.append((newconf_ctx_keys, line)) else: lines_to_add.append((newconf_ctx_keys, None)) for line in newconf_ctx.lines: lines_to_add.append((newconf_ctx_keys, line)) # if we have some candidate paths commands to add, append them to lines_to_add if len(candidates_to_add) > 0: lines_to_add.extend(candidates_to_add) (lines_to_add, lines_to_del) = ignore_delete_re_add_lines( lines_to_add, lines_to_del ) (lines_to_add, lines_to_del) = delete_move_lines(lines_to_add, lines_to_del) (lines_to_add, lines_to_del) = ignore_unconfigurable_lines( lines_to_add, lines_to_del ) return (lines_to_add, lines_to_del) if __name__ == "__main__": # Command line options parser = argparse.ArgumentParser( description="Dynamically apply diff in frr configs" ) parser.add_argument( "--input", help='Read running config from file instead of "show running"' ) group = parser.add_mutually_exclusive_group(required=True) group.add_argument( "--reload", action="store_true", help="Apply the deltas", default=False ) group.add_argument( "--test", action="store_true", help="Show the deltas", default=False ) level_group = parser.add_mutually_exclusive_group() level_group.add_argument( "--debug", action="store_true", help="Enable debugs (synonym for --log-level=debug)", default=False, ) level_group.add_argument( "--log-level", help="Log level", default="info", choices=("critical", "error", "warning", "info", "debug"), ) parser.add_argument( "--stdout", action="store_true", help="Log to STDOUT", default=False ) parser.add_argument( "--pathspace", "-N", metavar="NAME", help="Reload specified path/namespace", default=None, ) parser.add_argument("filename", help="Location of new frr config file") parser.add_argument( "--overwrite", action="store_true", help="Overwrite frr.conf with running config output", default=False, ) parser.add_argument( "--bindir", help="path to the vtysh executable", default="/usr/bin" ) parser.add_argument( "--confdir", help="path to the daemon config files", default="/etc/frr" ) parser.add_argument( "--rundir", help="path for the temp config file", default="/var/run/frr" ) parser.add_argument( "--vty_socket", help="socket to be used by vtysh to connect to the daemons", default=None, ) parser.add_argument( "--daemon", help="daemon for which want to replace the config", default="" ) parser.add_argument( "--test-reset", action="store_true", help="Used by topotest to not delete debug or log file commands", ) args = parser.parse_args() # Logging # For --test log to stdout # For --reload log to /var/log/frr/frr-reload.log if args.test or args.stdout: logging.basicConfig(format="%(asctime)s %(levelname)5s: %(message)s") # Color the errors and warnings in red logging.addLevelName( logging.ERROR, "\033[91m %s\033[0m" % logging.getLevelName(logging.ERROR) ) logging.addLevelName( logging.WARNING, "\033[91m%s\033[0m" % logging.getLevelName(logging.WARNING) ) elif args.reload: if not os.path.isdir("/var/log/frr/"): os.makedirs("/var/log/frr/", mode=0o0755) logging.basicConfig( filename="/var/log/frr/frr-reload.log", format="%(asctime)s %(levelname)5s: %(message)s", ) # argparse should prevent this from happening but just to be safe... else: raise Exception("Must specify --reload or --test") log = logging.getLogger(__name__) if args.debug: log.setLevel(logging.DEBUG) else: log.setLevel(args.log_level.upper()) if args.reload and not args.stdout: # Additionally send errors and above to STDOUT, with no metadata, # when we are logging to a file. This specifically does not follow # args.log_level, and is analagous to behaviour in earlier versions # which additionally logged most errors using print(). stdout_hdlr = logging.StreamHandler(sys.stdout) stdout_hdlr.setLevel(logging.ERROR) stdout_hdlr.setFormatter(logging.Formatter()) log.addHandler(stdout_hdlr) # Verify the new config file is valid if not os.path.isfile(args.filename): log.error("Filename %s does not exist" % args.filename) sys.exit(1) if not os.path.getsize(args.filename): log.error("Filename %s is an empty file" % args.filename) sys.exit(1) # Verify that confdir is correct if not os.path.isdir(args.confdir): log.error("Confdir %s is not a valid path" % args.confdir) sys.exit(1) # Verify that bindir is correct if not os.path.isdir(args.bindir) or not os.path.isfile(args.bindir + "/vtysh"): log.error("Bindir %s is not a valid path to vtysh" % args.bindir) sys.exit(1) # verify that the vty_socket, if specified, is valid if args.vty_socket and not os.path.isdir(args.vty_socket): log.error("vty_socket %s is not a valid path" % args.vty_socket) sys.exit(1) # verify that the daemon, if specified, is valid if args.daemon and args.daemon not in [ "zebra", "bgpd", "fabricd", "isisd", "babeld", "ospf6d", "ospfd", "pbrd", "pimd", "pim6d", "ripd", "ripngd", "sharpd", "staticd", "vrrpd", "ldpd", "nhrpd", "pathd", "bfdd", "eigrpd", ]: msg = "Daemon %s is not a valid option for 'show running-config'" % args.daemon print(msg) log.error(msg) sys.exit(1) vtysh = Vtysh(args.bindir, args.confdir, args.vty_socket, args.pathspace) # Verify that 'service integrated-vtysh-config' is configured if args.pathspace: vtysh_filename = args.confdir + "/" + args.pathspace + "/vtysh.conf" else: vtysh_filename = args.confdir + "/vtysh.conf" service_integrated_vtysh_config = True if os.path.isfile(vtysh_filename): with open(vtysh_filename, "r") as fh: for line in fh.readlines(): line = line.strip() if line == "no service integrated-vtysh-config": service_integrated_vtysh_config = False break if not args.test and not service_integrated_vtysh_config and not args.daemon: log.error( "'service integrated-vtysh-config' is not configured, this is required for 'service frr reload'" ) sys.exit(1) log.info('Called via "%s"', str(args)) # Create a Config object from the config generated by newconf newconf = Config(vtysh) try: newconf.load_from_file(args.filename) reload_ok = True except VtyshException as ve: log.error("vtysh failed to process new configuration: {}".format(ve)) reload_ok = False if args.test: # Create a Config object from the running config running = Config(vtysh) if args.input: running.load_from_file(args.input) else: running.load_from_show_running(args.daemon) (lines_to_add, lines_to_del) = compare_context_objects(newconf, running) if lines_to_del: if not args.test_reset: print("\nLines To Delete") print("===============") for ctx_keys, line in lines_to_del: if line == "!": continue nolines = lines_to_config(ctx_keys, line, True) if args.test_reset: # For topotests the original code stripped the lines, and ommitted blank lines # after, do that here nolines = [x.strip() for x in nolines] # For topotests leave these lines in (don't delete them) # [chopps: why is "log file" more special than other "log" commands?] nolines = [ x for x in nolines if "debug" not in x and "log file" not in x ] if not nolines: continue cmd = "\n".join(nolines) print(cmd) if lines_to_add: if not args.test_reset: print("\nLines To Add") print("============") for ctx_keys, line in lines_to_add: if line == "!": continue lines = lines_to_config(ctx_keys, line, False) if args.test_reset: # For topotests the original code stripped the lines, and ommitted blank lines # after, do that here lines = [x.strip() for x in lines if x.strip()] if not lines: continue cmd = "\n".join(lines) print(cmd) elif args.reload: lines_to_configure = [] # We will not be able to do anything, go ahead and exit(1) if not vtysh.is_config_available() or not reload_ok: sys.exit(1) log.debug("New Frr Config\n%s", newconf.get_lines()) # This looks a little odd but we have to do this twice...here is why # If the user had this running bgp config: # # router bgp 10 # neighbor 1.1.1.1 remote-as 50 # neighbor 1.1.1.1 route-map FOO out # # and this config in the newconf config file # # router bgp 10 # neighbor 1.1.1.1 remote-as 999 # neighbor 1.1.1.1 route-map FOO out # # # Then the script will do # - no neighbor 1.1.1.1 remote-as 50 # - neighbor 1.1.1.1 remote-as 999 # # The problem is the "no neighbor 1.1.1.1 remote-as 50" will also remove # the "neighbor 1.1.1.1 route-map FOO out" line...so we compare the # configs again to put this line back. # There are many keywords in FRR that can only appear one time under # a context, take "bgp router-id" for example. If the config that we are # reloading against has the following: # # router bgp 10 # bgp router-id 1.1.1.1 # bgp router-id 2.2.2.2 # # The final config needs to contain "bgp router-id 2.2.2.2". On the # first pass we will add "bgp router-id 2.2.2.2" but then on the second # pass we will see that "bgp router-id 1.1.1.1" is missing and add that # back which cancels out the "bgp router-id 2.2.2.2". The fix is for the # second pass to include all of the "adds" from the first pass. lines_to_add_first_pass = [] for x in range(2): running = Config(vtysh) running.load_from_show_running(args.daemon) log.debug("Running Frr Config (Pass #%d)\n%s", x, running.get_lines()) (lines_to_add, lines_to_del) = compare_context_objects(newconf, running) if x == 0: lines_to_add_first_pass = lines_to_add else: lines_to_add.extend(lines_to_add_first_pass) # Only do deletes on the first pass. The reason being if we # configure a bgp neighbor via "neighbor swp1 interface" FRR # will automatically add: # # interface swp1 # ipv6 nd ra-interval 10 # no ipv6 nd suppress-ra # ! # # but those lines aren't in the config we are reloading against so # on the 2nd pass they will show up in lines_to_del. This could # apply to other scenarios as well where configuring FOO adds BAR # to the config. if lines_to_del and x == 0: for ctx_keys, line in lines_to_del: if line == "!": continue # 'no' commands are tricky, we can't just put them in a file and # vtysh -f that file. See the next comment for an explanation # of their quirks cmd = lines_to_config(ctx_keys, line, True) original_cmd = cmd # Some commands in frr are picky about taking a "no" of the entire line. # OSPF is bad about this, you can't "no" the entire line, you have to "no" # only the beginning. If we hit one of these command an exception will be # thrown. Catch it and remove the last '-c', 'FOO' from cmd and try again. # # Example: # frr(config-if)# ip ospf authentication message-digest 1.1.1.1 # frr(config-if)# no ip ospf authentication message-digest 1.1.1.1 # % Unknown command. # frr(config-if)# no ip ospf authentication message-digest # % Unknown command. # frr(config-if)# no ip ospf authentication # frr(config-if)# stdouts = [] while True: try: vtysh(["configure"] + cmd, stdouts) except VtyshException: # - Pull the last entry from cmd (this would be # 'no ip ospf authentication message-digest 1.1.1.1' in # our example above # - Split that last entry by whitespace and drop the last word log.error("Failed to execute %s", " ".join(cmd)) last_arg = cmd[-1].split(" ") if len(last_arg) <= 2: log.error( '"%s" we failed to remove this command', " -- ".join(original_cmd), ) # Log first error msg for original_cmd if stdouts: log.error(stdouts[0]) reload_ok = False break new_last_arg = last_arg[0:-1] cmd[-1] = " ".join(new_last_arg) else: log.info('Executed "%s"', " ".join(cmd)) break if lines_to_add: lines_to_configure = [] for ctx_keys, line in lines_to_add: if line == "!": continue # Don't run "no" commands twice since they can error # out the second time due to first deletion if x == 1 and ctx_keys[0].startswith("no "): continue cmd = "\n".join(lines_to_config(ctx_keys, line, False)) + "\n" lines_to_configure.append(cmd) if lines_to_configure: random_string = "".join( random.SystemRandom().choice( string.ascii_uppercase + string.digits ) for _ in range(6) ) filename = args.rundir + "/reload-%s.txt" % random_string log.info("%s content\n%s" % (filename, pformat(lines_to_configure))) with open(filename, "w") as fh: for line in lines_to_configure: fh.write(line + "\n") try: vtysh.exec_file(filename) except VtyshException as e: log.warning("frr-reload.py failed due to\n%s" % e.args) reload_ok = False os.unlink(filename) # Make these changes persistent target = str(args.confdir + "/frr.conf") if args.overwrite or (not args.daemon and args.filename != target): vtysh("write") if not reload_ok: sys.exit(1)