util.sslconfig: Add lib to deal with LuaSec SSL context configs

1 files changed, 87 insertions, 0 deletions

diff --git a/util/sslconfig.lua b/util/sslconfig.lua
new file mode 100644
index 00000000..98e61341
--- /dev/null
+++ b/util/sslconfig.lua
@@ -0,0 +1,87 @@
+
+local handlers = { };
+local finalisers = { };
+local id = function (v) return v end
+
+function handlers.options(a, k, b)
+	local o = a[k] or { };
+	if type(b) ~= "table" then b = { b } end
+	for k,v in pairs(b) do
+		if v == true or v == false then
+			o[k] = v;
+		else
+			o[v] = true;
+		end
+	end
+	a[k] = o;
+end
+
+handlers.verify = handlers.options;
+handlers.verifyext = handlers.options;
+
+function finalisers.options(a)
+	local o = {};
+	for opt, enable in pairs(a) do
+		if enable then
+			o[#o+1] = opt;
+		end
+	end
+	return o;
+end
+
+finalisers.verify = finalisers.options;
+finalisers.verifyext = finalisers.options;
+
+function finalisers.ciphers(a)
+	if type(a) == "table" then
+		return table.concat(a, ":");
+	end
+	return a;
+end
+
+local protocols = { "sslv2", "sslv3", "tlsv1", "tlsv1_1", "tlsv1_2" };
+for i = 1, #protocols do protocols[protocols[i] .. "+"] = i - 1; end
+
+local function protocol(a)
+	local min_protocol = protocols[a.protocol];
+	if min_protocol then
+		a.protocol = "sslv23";
+		for i = 1, min_protocol do
+			table.insert(a.options, "no_"..protocols[i]);
+		end
+	end
+end
+
+local function apply(a, b)
+	if type(b) == "table" then
+		for k,v in pairs(b) do
+			(handlers[k] or rawset)(a, k, v);
+		end
+	end
+end
+
+local function final(a)
+	local f = { };
+	for k,v in pairs(a) do
+		f[k] = (finalisers[k] or id)(v);
+	end
+	protocol(f);
+	return f;
+end
+
+local sslopts_mt = {
+	__index = {
+		apply = apply;
+		final = final;
+	};
+};
+
+local function new()
+	return setmetatable({options={}}, sslopts_mt);
+end
+
+return {
+	apply = apply;
+	final = final;
+	new = new;
+};