(* HCoop Domtool (http://hcoop.sourceforge.net/)
* Copyright (c) 2006-2007, Adam Chlipala
+ * Copyright (c) 2011,2012,2013,2014,2018 Clinton Ebadi
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*)
-(* Firewall rule querying *)
+(* Firewall management *)
+
+(* Contains portions from Fwtool Copyright (C) 2005 Adam Chlipala, GPL v2 or later *)
structure Firewall :> FIREWALL = struct
-fun query uname =
+datatype user = User of string
+
+datatype fwnode = FirewallNode of string
+
+datatype fwrule = Client of int list * string list
+ | Server of int list * string list
+ | ProxiedServer of int list
+ | LocalServer of int list
+
+type firewall_rules = (user * fwnode * fwrule) list
+
+datatype fwip = FwIPv4
+ | FwIPv6
+
+structure StringMap = DataStructures.StringMap
+
+fun parseRules () =
+ let
+ val inf = TextIO.openIn Config.Firewall.firewallRules
+
+ fun parsePorts ports =
+ List.mapPartial Int.fromString (String.fields (fn ch => ch = #",") ports)
+ (* Just drop bad ports for now *)
+
+ fun parseNodes nodes = String.fields (fn ch => ch = #",") nodes
+
+ fun loop parsedRules =
+ case TextIO.inputLine inf of
+ NONE => parsedRules
+ | SOME line =>
+ case String.tokens Char.isSpace line of
+ nodes :: uname :: rest =>
+ let
+ val nodes = parseNodes nodes
+ in
+ case rest of
+ "Client" :: ports :: hosts => loop (map (fn node => (User uname, FirewallNode node, Client (parsePorts ports, hosts))) nodes) @ parsedRules
+ | "Server" :: ports :: hosts => loop (map (fn node => (User uname, FirewallNode node, Server (parsePorts ports, hosts))) nodes) @ parsedRules
+ | ["ProxiedServer", ports] => loop (map (fn node => (User uname, FirewallNode node, ProxiedServer (parsePorts ports))) nodes) @ parsedRules
+ | ["LocalServer", ports] => loop (map (fn node => (User uname, FirewallNode node, LocalServer (parsePorts ports))) nodes) @ parsedRules
+ | _ => (print "Invalid config line\n"; loop parsedRules)
+ end
+ | _ => loop parsedRules
+ in
+ loop []
+ end
+
+fun formatQueryRule (Client (ports, hosts)) =
+ "Client " ^ String.concatWith "," (map Int.toString ports) ^ " " ^ String.concatWith " " hosts
+ | formatQueryRule (Server (ports, hosts)) =
+ "Server " ^ String.concatWith "," (map Int.toString ports) ^ " " ^ String.concatWith " " hosts
+ | formatQueryRule (ProxiedServer ports) =
+ "ProxiedServer " ^ String.concatWith "," (map Int.toString ports)
+ | formatQueryRule (LocalServer ports) =
+ "LocalServer " ^ String.concatWith "," (map Int.toString ports)
+
+fun query (node, uname) =
+ (* completely broken *)
+ let
+ val rules = parseRules ()
+ in
+ map (fn (_, _, r) => formatQueryRule r)
+ (List.filter (fn (User u, FirewallNode n, _) => u = uname andalso n = node) rules)
+ end
+
+fun validIp (ip, ipv6) = (case ipv6 of FwIPv6 => Domain.validIpv6 ip
+ | FwIPv4 => Domain.validIp ip)
+
+fun dnsExists dnsRR dnsRecord =
let
- val inf = TextIO.openIn "/etc/firewall/users.rules"
-
- fun loop rules =
- case TextIO.inputLine inf of
- NONE => List.rev rules
- | SOME line =>
- if String.sub (line, 0) = #"#" then
- loop rules
- else case String.tokens Char.isSpace line of
- uname'::rest =>
- if uname = uname' then
- loop (String.concatWith " " rest :: rules)
- else
- loop rules
- | _ => loop rules
+ val dnsRR_string = case dnsRR of
+ FwIPv6 => "AAAA"
+ | FwIPv4 => "A"
in
- loop []
- before TextIO.closeIn inf
- end handle IO.Io _ => []
+ (* timeout chosen arbitrarilty, shorter is better if it's reliable *)
+ (* dig outputs true even if the lookup fails, but no output in short mode should work *)
+ case Slave.runOutput (Config.Firewall.dig, ["+short", "+timeout=3", "-t", dnsRR_string, dnsRecord]) of
+ (_, SOME s) => (validIp (List.last (String.tokens Char.isSpace s), dnsRR))
+ | (x, NONE) => false
+ end
+
+fun fermVariable x = String.isPrefix "$" x
+fun filterHosts (hosts, ipv6) =
+ List.filter (fn host => (fermVariable host
+ orelse validIp (host, ipv6)
+ orelse dnsExists ipv6 host))
+ hosts
+
+
+fun formatPorts ports = "(" ^ String.concatWith " " (map Int.toString ports) ^ ")"
+fun formatHosts (hosts, ipv6) = "(" ^ String.concatWith " " (filterHosts (hosts, ipv6)) ^ ")"
+
+fun formatOutputRule (Client (ports, hosts), ipv6) = "dport " ^ formatPorts ports ^ (case hosts of
+ [] => ""
+ | _ => " daddr " ^ formatHosts (hosts, ipv6)) ^ " ACCEPT;"
+ | formatOutputRule _ = ""
+
+fun formatInputRule (Server (ports, hosts), ipv6) = "dport " ^ formatPorts ports ^ (case hosts of
+ [] => ""
+ | _ => " saddr " ^ formatHosts (hosts, ipv6)) ^ " ACCEPT;"
+ | formatInputRule _ = ""
+
+type ferm_lines = { input_rules : (string list) DataStructures.StringMap.map,
+ output_rules : (string list) DataStructures.StringMap.map }
+
+fun generateNodeFermRules rules =
+ let
+ fun filter_node_rules rules =
+ List.filter (fn (uname, FirewallNode node, rule) => node = Slave.hostname () orelse case rule of
+ ProxiedServer _ => List.exists (fn (h,_) => h = Slave.hostname ()) Config.Apache.webNodes_all
+ | _ => false)
+ rules
+
+ val inputLines = ref StringMap.empty
+ val outputLines = ref StringMap.empty
+ val inputLines_v6 = ref StringMap.empty
+ val outputLines_v6 = ref StringMap.empty
+
+ fun confLine r (User uname, line) =
+ let
+ val line = "\t" ^ line ^ "\n"
+ val lines = case StringMap.find (!r, uname) of
+ NONE => []
+ | SOME lines => lines
+ in
+ r := StringMap.insert (!r, uname, line :: lines)
+ end
+
+ fun confLine_in (uname, rule) = confLine inputLines (uname, formatInputRule (rule, FwIPv4))
+ fun confLine_out (uname, rule) = confLine outputLines (uname, formatOutputRule (rule, FwIPv4))
+ fun confLine_in_v6 (uname, rule) = confLine inputLines_v6 (uname, formatInputRule (rule, FwIPv6))
+ fun confLine_out_v6 (uname, rule) = confLine outputLines_v6 (uname, formatOutputRule (rule, FwIPv6))
+
+ fun insertConfLine (uname, ruleNode, rule) =
+ let
+ val fwnode_domain = fn FirewallNode node => node ^ "." ^ Config.defaultDomain
+ in
+ case rule of
+ Client (ports, hosts) => (confLine_out (uname, rule); confLine_out_v6 (uname, rule))
+ | Server (ports, hosts) => (confLine_in (uname, rule); confLine_in_v6 (uname, rule))
+ | LocalServer ports => (insertConfLine (uname, ruleNode, Client (ports, ["127.0.0.1/8"]));
+ insertConfLine (uname, ruleNode, Server (ports, ["127.0.0.1/8"]));
+ insertConfLine (uname, ruleNode, Client (ports, [":::1"]));
+ insertConfLine (uname, ruleNode, Server (ports, [":::1"])))
+ | ProxiedServer ports => if (fn FirewallNode r => r) ruleNode = Slave.hostname () then
+ (insertConfLine (uname, ruleNode, Server (ports, ["$WEBNODES"]));
+ insertConfLine (uname, ruleNode, Client (ports, [fwnode_domain ruleNode])))
+ else (* we are a web server *)
+ (insertConfLine (uname, ruleNode, Client (ports, [fwnode_domain ruleNode]));
+ insertConfLine (User "www-data", ruleNode, Client (ports, [fwnode_domain ruleNode])))
+ end
+
+ val _ = map insertConfLine (filter_node_rules rules)
+ in
+ { input_rules = !inputLines,
+ output_rules = !outputLines,
+ input6_rules = !inputLines_v6,
+ output6_rules = !outputLines_v6 }
+
+
+ end
+
+fun generateFirewallConfig rules =
+ (* rule generation must happen on the node (mandating the even
+ service users be pts users would make it possible to do on the
+ server, but that's not happening any time soon) *)
+ let
+ val users_tcp_out_conf = TextIO.openOut (Config.Firewall.firewallDir ^ "/users_tcp_out.conf")
+ val users_tcp_in_conf = TextIO.openOut (Config.Firewall.firewallDir ^ "/users_tcp_in.conf")
+
+ val users_tcp6_out_conf = TextIO.openOut (Config.Firewall.firewallDir ^ "/users_tcp6_out.conf")
+ val users_tcp6_in_conf = TextIO.openOut (Config.Firewall.firewallDir ^ "/users_tcp6_in.conf")
+
+ val nodeFermRules = generateNodeFermRules rules
+
+ fun write_tcp_in_conf_preamble outf =
+ TextIO.output (outf, String.concat ["@def $WEBNODES = @ipfilter((",
+ (String.concatWith " " (List.map (fn (_, ip, ipv6) => ip ^ " " ^ "[" ^ ipv6 ^ "]")
+ (List.filter (fn (node, _, _) => List.exists (fn (n) => n = node) (List.map (fn (node, _) => node) (Config.Apache.webNodes_all @ Config.Apache.webNodes_admin)))
+ Config.nodeIps))),
+ "));\n\n"])
+
+ fun writeUserInRules tcp_inf (uname, lines) =
+ (* We can't match the user when listening; SELinux or
+ similar would let us manage this with better
+ granularity.*)
+ let
+ val _ = SysWord.toInt (Posix.ProcEnv.uidToWord (Posix.SysDB.Passwd.uid (Posix.SysDB.getpwnam uname)))
+ in
+ TextIO.output (tcp_inf, "proto tcp mod comment comment \"user:" ^ uname ^ "\" {\n");
+ TextIO.output (tcp_inf, concat lines);
+ TextIO.output (tcp_inf, "\n}\n\n")
+ end handle OS.SysErr _ => print ("Invalid user " ^ uname ^ " in firewall config, skipping.\n") (* no sense in opening ports for bad users *)
+
+ fun writeUserOutRules tcp_outf (uname, lines) =
+ let
+ val uid = SysWord.toInt (Posix.ProcEnv.uidToWord (Posix.SysDB.Passwd.uid (Posix.SysDB.getpwnam uname)))
+ in
+ TextIO.output (tcp_outf, "mod owner uid-owner " ^ (Int.toString uid) ^ " mod comment comment \"user:" ^ uname ^ "\" proto tcp {\n");
+ TextIO.output (tcp_outf, concat lines);
+ TextIO.output (tcp_outf, "\nDROP;\n}\n\n")
+ end handle OS.SysErr _ => print ("Invalid user " ^ uname ^ " in firewall config, skipping.\n")
+
+ in
+ write_tcp_in_conf_preamble (users_tcp_in_conf);
+ StringMap.appi (writeUserOutRules users_tcp_out_conf) (#output_rules nodeFermRules);
+ StringMap.appi (writeUserInRules users_tcp_in_conf) (#input_rules nodeFermRules);
+
+ write_tcp_in_conf_preamble (users_tcp6_in_conf);
+ StringMap.appi (writeUserOutRules users_tcp6_out_conf) (#output6_rules nodeFermRules);
+ StringMap.appi (writeUserInRules users_tcp6_in_conf) (#input6_rules nodeFermRules);
+
+ TextIO.closeOut users_tcp_out_conf;
+ TextIO.closeOut users_tcp_in_conf;
+
+ TextIO.closeOut users_tcp6_out_conf;
+ TextIO.closeOut users_tcp6_in_conf;
+
+ true
+ end
+fun publishConfig _ =
+ Slave.shell [Config.Firewall.reload]
end
HCoop / hcoop / domtool2.git / blobdiff