(* HCoop Domtool (http://hcoop.sourceforge.net/)
* Copyright (c) 2006-2007, Adam Chlipala
- * Copyright (c) 2011 Clinton Ebadi
+ * Copyright (c) 2011,2012,2013,2014 Clinton Ebadi
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
structure Firewall :> FIREWALL = struct
-type firewall_rules = { server_rules : (string list DataStructures.StringMap.map),
- client_rules : (string list DataStructures.StringMap.map)}
+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
structure StringMap = DataStructures.StringMap
-fun parseRules _ =
+fun parseRules () =
let
val inf = TextIO.openIn Config.Firewall.firewallRules
- val out_lines = ref StringMap.empty
- val in_lines = ref StringMap.empty
-
- fun confLine r (uname, line) =
- let
- val line = String.concat ["\t", line, "\n"]
- val lines = case StringMap.find (!r, uname) of
- NONE => []
- | SOME lines => lines
- in
- r := StringMap.insert (!r, uname, line :: lines)
- end
-
- val confLine_in = confLine in_lines
- val confLine_out = confLine out_lines
fun parsePorts ports =
- case String.fields (fn ch => ch = #",") ports of
- [pp] => pp
- | pps => String.concat ["(", String.concatWith " " pps, ")"]
+ List.mapPartial Int.fromString (String.fields (fn ch => ch = #",") ports)
+ (* Just drop bad ports for now *)
- fun parseHosts addr hosts =
- case hosts of
- [] => ""
- | [host] => String.concat [" ", addr, " ", host]
- | _ => String.concat [" ", addr, " (", String.concatWith " " hosts, ")"]
-
- fun loop () =
+ fun loop parsedRules =
case TextIO.inputLine inf of
- NONE => ()
+ NONE => parsedRules
| SOME line =>
case String.tokens Char.isSpace line of
- uname :: rest =>
+ node :: uname :: rest =>
(case rest of
- "Client" :: ports :: hosts =>
- confLine_out (uname, String.concat ["dport ", parsePorts ports, parseHosts "daddr" hosts, " ACCEPT;"])
- | "Server" :: ports :: hosts =>
- confLine_in (uname, String.concat ["dport ", parsePorts ports, parseHosts "daddr" hosts, " ACCEPT;"])
- | ["LocalServer", ports] =>
- confLine_in (uname, String.concat ["saddr $WE dport ", parsePorts ports, " ACCEPT;"])
- | _ => print "Invalid config line\n";
- loop ())
- | _ => loop ()
- val _ = loop ()
+ "Client" :: ports :: hosts => loop ((User uname, FirewallNode node, Client (parsePorts ports, hosts)) :: parsedRules)
+ | "Server" :: ports :: hosts => loop ((User uname, FirewallNode node, Server (parsePorts ports, hosts)) :: parsedRules)
+ | ["ProxiedServer", ports] => loop ((User uname, FirewallNode node, ProxiedServer (parsePorts ports)) :: parsedRules)
+ | ["LocalServer", ports] => loop ((User uname, FirewallNode node, LocalServer (parsePorts ports)) :: parsedRules)
+ | _ => (print "Invalid config line\n"; loop parsedRules))
+ | _ => loop parsedRules
in
- {server_rules = !in_lines, client_rules = !out_lines}
+ loop []
end
-fun query uname =
+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
- getOpt (StringMap.find (#server_rules rules, uname), []) @ getOpt (StringMap.find (#client_rules rules, uname), [])
+ map (fn (_, _, r) => formatQueryRule r)
+ (List.filter (fn (User u, FirewallNode n, _) => u = uname andalso n = node) rules)
end
+fun formatPorts ports = "(" ^ String.concatWith " " (map Int.toString ports) ^ ")"
+fun formatHosts hosts = "(" ^ String.concatWith " " hosts ^ ")"
+
+fun formatOutputRule (Client (ports, hosts)) = "dport " ^ formatPorts ports ^ (case hosts of
+ [] => ""
+ | _ => " daddr " ^ formatHosts hosts) ^ " ACCEPT;"
+ | formatOutputRule _ = ""
+
+fun formatInputRule (Server (ports, hosts)) = "dport " ^ formatPorts ports ^ (case hosts of
+ [] => ""
+ | _ => " saddr " ^ formatHosts hosts) ^ " 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
-fun generateFirewallConfig {server_rules, client_rules} =
-(* rule generation must happen on the node (not really, but I'd rather
- avoid codifying that uids must be consistent between hosts) *)
+ 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)
+ fun confLine_out (uname, rule) = confLine outputLines (uname, formatOutputRule rule)
+
+ fun insertConfLine (uname, ruleNode, rule) =
+ case rule of
+ Client (ports, hosts) => confLine_out (uname, rule)
+ | Server (ports, hosts) => confLine_in (uname, rule)
+ | LocalServer ports => (insertConfLine (uname, ruleNode, Client (ports, ["127.0.0.1/8"]));
+ insertConfLine (uname, ruleNode, Server (ports, ["127.0.0.1/8"])))
+ | ProxiedServer ports => if (fn FirewallNode r => r) ruleNode = Slave.hostname () then
+ (insertConfLine (uname, ruleNode, Server (ports, ["$WEBNODES"]));
+ insertConfLine (uname, ruleNode, Client (ports, [(fn FirewallNode r => r) ruleNode])))
+ else (* we are a web server *)
+ (insertConfLine (uname, ruleNode, Client (ports, [(fn FirewallNode r => r) ruleNode]));
+ insertConfLine (User "www-data", ruleNode, Client (ports, [(fn FirewallNode r => r) ruleNode])))
+
+ val _ = map insertConfLine (filter_node_rules rules)
+ in
+ { input_rules = !inputLines,
+ output_rules = !outputLines }
+
+
+ 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_conf = TextIO.openOut (Config.Firewall.firewallDir ^ "/users.conf")
-
- fun write_user_tcp_conf (rules, outf, suffix) =
- StringMap.appi (fn (uname, lines) =>
- let
- val uid = SysWord.toInt (Posix.ProcEnv.uidToWord (Posix.SysDB.Passwd.uid (Posix.SysDB.getpwnam uname)))
- in
- TextIO.output (outf, String.concat
- ["mod owner uid-owner ",
- Int.toString uid,
- " { goto user_",
- uname,
- suffix,
- "; goto lreject; }\n"]);
- (* Is there any point to splitting the rules like this? *)
- TextIO.output (users_conf,
- String.concat ("chain user_"
- :: uname
- :: suffix
- :: " proto tcp {\n"
- :: lines
- @ ["}\n\n"]))
- end handle OS.SysErr _ => print "Invalid user in firewall config, skipping.\n")
- rules
+ val user_chains_conf = TextIO.openOut (Config.Firewall.firewallDir ^ "/user_chains.conf")
+
+ val nodeFermRules = generateNodeFermRules rules
+
+ fun write_tcp_in_conf_preamble outf =
+ TextIO.output (outf, String.concat ["@def $WEBNODES = (",
+ (String.concatWith " " (List.map (fn (_, ip) => ip)
+ (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 (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 (users_tcp_in_conf, "proto tcp {\n");
+ TextIO.output (users_tcp_in_conf, concat lines);
+ TextIO.output (users_tcp_in_conf, "\n}\n\n")
+ end handle OS.SysErr _ => print "Invalid user in firewall config, skipping.\n" (* no sense in opening ports for bad users *)
+
+ fun writeUserOutRules (uname, lines) =
+ let
+ val uid = SysWord.toInt (Posix.ProcEnv.uidToWord (Posix.SysDB.Passwd.uid (Posix.SysDB.getpwnam uname)))
+ in
+ TextIO.output (users_tcp_out_conf, "mod owner uid-owner " ^ (Int.toString uid)
+ ^ " { jump user_" ^ uname ^ "_tcp_out"
+ ^ "; DROP; }\n");
+
+ TextIO.output (user_chains_conf, "chain user_" ^ uname ^ "_tcp_out"
+ ^ " proto tcp {\n");
+ TextIO.output (user_chains_conf, concat lines);
+ TextIO.output (user_chains_conf, "\n}\n\n")
+ end handle OS.SysErr _ => print "Invalid user in firewall config, skipping.\n"
+
in
- write_user_tcp_conf (server_rules, users_tcp_in_conf, "_tcp_in");
- write_user_tcp_conf (client_rules, users_tcp_out_conf, "_tcp_out");
+ write_tcp_in_conf_preamble (users_tcp_in_conf);
+ StringMap.appi (writeUserOutRules) (#output_rules nodeFermRules);
+ StringMap.appi (writeUserInRules) (#input_rules nodeFermRules);
- TextIO.closeOut users_conf;
+ TextIO.closeOut user_chains_conf;
TextIO.closeOut users_tcp_out_conf;
TextIO.closeOut users_tcp_in_conf;