util.openssl: Add wrapper for the openssl cli tool and move certificate config logic from util.x509 into it.

util/openssl.lua

@@ -0,0 +1,156 @@
+local type, tostring, pairs, ipairs = type, tostring, pairs, ipairs;
+local t_insert, t_concat = table.insert, table.concat;
+local s_format = string.format;
+
+local oid_xmppaddr = "1.3.6.1.5.5.7.8.5"; -- [XMPP-CORE]
+local oid_dnssrv   = "1.3.6.1.5.5.7.8.7"; -- [SRV-ID]
+
+local idna_to_ascii = require "util.encodings".idna.to_ascii;
+
+local _M = {};
+local config = {};
+_M.config = config;
+
+local ssl_config = {};
+local ssl_config_mt = {__index=ssl_config};
+
+function config.new()
+	return setmetatable({
+		req = {
+			distinguished_name = "distinguished_name",
+			req_extensions = "v3_extensions",
+			x509_extensions = "v3_extensions",
+			prompt = "no",
+		},
+		distinguished_name = {
+			commonName = "example.com",
+			countryName = "GB",
+			localityName = "The Internet",
+			organizationName = "Your Organisation",
+			organizationalUnitName = "XMPP Department",
+			emailAddress = "xmpp@example.com",
+		},
+		v3_extensions = {
+			basicConstraints = "CA:FALSE",
+			keyUsage = "digitalSignature,keyEncipherment",
+			extendedKeyUsage = "serverAuth,clientAuth",
+			subjectAltName = "@subject_alternative_name",
+		},
+		subject_alternative_name = {
+			DNS = {},
+			otherName = {},
+		},
+	}, ssl_config_mt);
+end
+
+function ssl_config:serialize()
+	local s = "";
+	for k, t in pairs(self) do
+		s = s .. ("[%s]\n"):format(k);
+		if k == "subject_alternative_name" then
+			for san, n in pairs(t) do
+				for i = 1,#n do
+					s = s .. s_format("%s.%d = %s\n", san, i -1, n[i]);
+				end
+			end
+		else
+			for k, v in pairs(t) do
+				s = s .. ("%s = %s\n"):format(k, v);
+			end
+		end
+		s = s .. "\n";
+	end
+	return s;
+end
+
+local function utf8string(s)
+	-- This is how we tell openssl not to encode UTF-8 strings as fake Latin1
+	return s_format("FORMAT:UTF8,UTF8:%s", s);
+end
+
+local function ia5string(s)
+	return s_format("IA5STRING:%s", s);
+end
+
+local util = {};
+_M.util = {
+	utf8string = utf8string,
+	ia5string = ia5string,
+};
+
+local function xmppAddr(t, host)
+end
+
+function ssl_config:add_dNSName(host)
+	t_insert(self.subject_alternative_name.DNS, idna_to_ascii(host));
+end
+
+function ssl_config:add_sRVName(host, service)
+	t_insert(self.subject_alternative_name.otherName,
+		s_format("%s;%s", oid_dnssrv, ia5string("_" .. service .."." .. idna_to_ascii(host))));
+end
+
+function ssl_config:add_xmppAddr(host)
+	t_insert(self.subject_alternative_name.otherName,
+		s_format("%s;%s", oid_xmppaddr, utf8string(host)));
+end
+
+function ssl_config:from_prosody(hosts, config, certhosts, raw)
+	-- TODO Decide if this should go elsewhere
+	local found_matching_hosts = false;
+	for i = 1,#certhosts do
+		local certhost = certhosts[i];
+		for name, host in pairs(hosts) do
+			if name == certhost or name:sub(-1-#certhost) == "."..certhost then
+				found_matching_hosts = true;
+				self:add_dNSName(name);
+				--print(name .. "#component_module: " .. (config.get(name, "core", "component_module") or "nil"));
+				if config.get(name, "core", "component_module") == nil then
+					self:add_sRVName(name, "xmpp-client");
+				end
+				--print(name .. "#anonymous_login: " .. tostring(config.get(name, "core", "anonymous_login")));
+				if not (config.get(name, "core", "anonymous_login") or
+						config.get(name, "core", "authentication") == "anonymous") then
+					self:add_sRVName(name, "xmpp-server");
+				end
+				self:add_xmppAddr(name);
+			end
+		end
+	end
+	if not found_matching_hosts then
+		return nil, "no-matching-hosts";
+	end
+end
+
+do -- Lua to shell calls.
+	local function shell_escape(s)
+		return s:gsub("'",[['\'']]);
+	end
+
+	local function serialize(f,o)
+		local r = {"openssl", f};
+		for k,v in pairs(o) do
+			if type(k) == "string" then
+				t_insert(r, ("-%s"):format(k));
+				if v ~= true then
+					t_insert(r, ("'%s'"):format(shell_escape(tostring(v))));
+				end
+			end
+		end
+		for k,v in ipairs(o) do
+			t_insert(r, ("'%s'"):format(shell_escape(tostring(v))));
+		end
+		return t_concat(r, " ");
+	end
+
+	local os_execute = os.execute;
+	setmetatable(_M, {
+		__index=function(self,f)
+			return function(opts)
+				return 0 == os_execute(serialize(f, type(opts) == "table" and opts or {}));
+			end;
+		end;
+	});
+end
+
+return _M;