Mercurial > prosody-modules

annotate mod_dnsupdate/mod_dnsupdate.lua @ 4816:e7d1d68f0279

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mod_export_skeletons: Document archive name override option This was why I went with argparse to begin with, so of course it was forgotten when I got to writing docs
author Kim Alvefur <zash@zash.se>
date Fri, 10 Dec 2021 00:01:17 +0100
parents 6395d4732bc6
children 28f6322fad50
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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ba312cd7907f mod_dnsupdate: Use with nsupdate to update DNS records from config
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1 module:set_global();
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2
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3 local config = require "core.configmanager";
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4 local argparse = require "util.argparse";
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5 local dns = require"net.adns".resolver();
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6 local async = require "util.async";
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7 local set = require "util.set";
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8 local nameprep = require"util.encodings".stringprep.nameprep;
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9 local idna_to_ascii = require"util.encodings".idna.to_ascii;
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10
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11 local virtualhost_services = { "xmpp-client"; "xmpps-client"; "xmpp-server"; "xmpps-server" }
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12 local component_services = { "xmpp-server"; "xmpps-server" }
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13
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14 local function validate_dnsname_option(options, option_name, default)
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15 local host = options[option_name];
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16 if host == nil then return default end
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17 local normalized = nameprep(host);
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18 if not normalized then
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19 module:log("error", "--%s %q fails normalization");
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20 return;
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21 end
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22 local alabel = idna_to_ascii(normalized);
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23 if not alabel then
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24 module:log("error", "--%s %q fails IDNA");
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25 return;
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26 end
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27 return alabel;
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28 end
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29
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30 function module.command(arg)
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31 local opts = argparse.parse(arg, {
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32 short_params = { d = "domain"; p = "primary"; t = "target"; l = "ttl"; h = "help"; ["?"] = "help" };
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33 value_params = { domain = true; primary = true; target = true; ttl = true };
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34 });
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35
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36 if not arg[1] or arg[2] or not opts or opts.help or not opts.domain then
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37 local out = opts.help and io.stdout or io.stderr;
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38 out:write("prosodyctl mod_dnsupdate [options] virtualhost\n");
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39 out:write("\t-d --domain\tbase domain name *required*\n");
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40 out:write("\t-p --primary\tprimary DNS name server\n");
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41 out:write("\t-t --target\ttarget hostname for SRV\n");
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42 out:write("\t-l --ttl\tTTL to use\n");
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43 out:write("\t--each\tremove and replace individual SRV records\n");
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44 out:write("\t--reset\tremove and replace all SRV records\n");
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45 return opts and opts.help and 0 or 1;
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46 end
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47
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48 local vhost = nameprep(arg[1]); -- TODO loop over arg[]?
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49 if not vhost then
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50 module:log("error", "Host %q fails normalization", arg[1]);
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51 return 1;
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52 end
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53 local ihost = idna_to_ascii(vhost);
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54 if not ihost then
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55 module:log("error", "Host %q falis IDNA", vhost);
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56 return 1;
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57 end
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58 local is_component = config.get(vhost, "component_module");
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59 if not is_component and not config.get(vhost, "defined") then
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60 module:log("error", "Host %q is not defined in the config", vhost);
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61 return 1;
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62 end
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63
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64 local services = virtualhost_services;
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65 if is_component then services = component_services; end
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66
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67 local domain = validate_dnsname_option(opts, "domain");
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68 if not domain then
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69 module:log("error", "--domain is required");
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70 return 1;
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71 end
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72 local primary = validate_dnsname_option(opts, "primary")
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73 or async.wait_for(dns:lookup_promise(domain, "SOA"):next(function(ret) return ret[1].soa.mname; end));
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74 if not primary then
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75 module:log("error", "Could not discover primary name server, specify it with --primary");
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76 return 1;
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77 end
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78 local target = validate_dnsname_option(opts, "target", module:context(vhost):get_option_string("xmpp_host", ihost));
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79 -- TODO validate that target has A/AAAA
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80
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81 local configured_ports = {
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82 ["xmpp-client"] = module:get_option_array("c2s_ports", { 5222 });
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83 ["xmpp-server"] = module:get_option_array("s2s_ports", { 5269 });
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84 ["xmpps-client"] = module:get_option_array("c2s_direct_tls_ports", {});
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85 ["xmpps-server"] = module:get_option_array("s2s_direct_tls_ports", {});
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86 };
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87
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88 if opts.multiplex then
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89 for opt, ports in pairs(configured_ports) do
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90 ports:append(module:get_option_array(opt:sub(1, 5) == "xmpps" and "ssl_ports" or "ports", {}));
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91 end
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92 end
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93
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94 local existing_srv = {};
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95 for _, service in ipairs(services) do
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96 existing_srv[service] = dns:lookup_promise(("_%s._tcp.%s"):format(service, ihost), "SRV");
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97 end
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98
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99 print("zone", domain);
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100 print("server", primary);
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101 print("ttl " .. tostring(opts.ttl or 60 * 60));
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102
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103 for _, service in ipairs(services) do
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104 local ports = set.new(configured_ports[service]);
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105 local records = (async.wait_for(existing_srv[service]));
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106 if opts.reset then
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107 print(("del _%s._tcp.%s IN SRV"):format(service, ihost));
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108 else
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109 for _, rr in ipairs(records) do
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110 if ports:contains(rr.srv.port) and target == nameprep(rr.srv.target):gsub("%.$", "") then
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111 ports:remove(rr.srv.port)
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112 elseif not opts.each then
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113 print(("del _%s._tcp.%s IN SRV"):format(service, ihost));
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114 break
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115 else
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116 print(("del _%s._tcp.%s IN SRV %s"):format(service, ihost, rr));
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117 end
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118 end
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119 end
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120 for port in ports do print(("add _%s._tcp.%s IN SRV 1 1 %d %s"):format(service, ihost, port, target)); end
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121 end
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122
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123 print("show");
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124 print("send");
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125 print("answer");
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126 end