mod_s2s_auth_certs: Split PKIX based certificate checking from mod_s2s into new plugin

3 files changed, 46 insertions, 34 deletions

diff --git a/core/modulemanager.lua b/core/modulemanager.lua
index eb1ce733..b5674ece 100644
--- a/core/modulemanager.lua
+++ b/core/modulemanager.lua
@@ -29,7 +29,7 @@ pcall = function(f, ...)
 	return xpcall(function() return f(unpack(params, 1, n)) end, function(e) return tostring(e).."\n"..debug_traceback(); end);
 end
 
-local autoload_modules = {prosody.platform, "presence", "message", "iq", "offline", "c2s", "s2s"};
+local autoload_modules = {prosody.platform, "presence", "message", "iq", "offline", "c2s", "s2s", "s2s_auth_certs"};
 local component_inheritable_modules = {"tls", "saslauth", "dialback", "iq", "s2s"};
 
 -- We need this to let modules access the real global namespace
diff --git a/plugins/mod_s2s/mod_s2s.lua b/plugins/mod_s2s/mod_s2s.lua
index e704c25a..f0d465c0 100644
--- a/plugins/mod_s2s/mod_s2s.lua
+++ b/plugins/mod_s2s/mod_s2s.lua
@@ -243,39 +243,6 @@ function check_cert_status(session)
 		cert = conn:getpeercertificate()
 	end
 
-	if cert then
-		local chain_valid, errors;
-		if conn.getpeerverification then
-			chain_valid, errors = conn:getpeerverification();
-		elseif conn.getpeerchainvalid then -- COMPAT mw/luasec-hg
-			chain_valid, errors = conn:getpeerchainvalid();
-			errors = (not chain_valid) and { { errors } } or nil;
-		else
-			chain_valid, errors = false, { { "Chain verification not supported by this version of LuaSec" } };
-		end
-		-- Is there any interest in printing out all/the number of errors here?
-		if not chain_valid then
-			(session.log or log)("debug", "certificate chain validation result: invalid");
-			for depth, t in pairs(errors or NULL) do
-				(session.log or log)("debug", "certificate error(s) at depth %d: %s", depth-1, table.concat(t, ", "))
-			end
-			session.cert_chain_status = "invalid";
-		else
-			(session.log or log)("debug", "certificate chain validation result: valid");
-			session.cert_chain_status = "valid";
-
-			-- We'll go ahead and verify the asserted identity if the
-			-- connecting server specified one.
-			if host then
-				if cert_verify_identity(host, "xmpp-server", cert) then
-					session.cert_identity_status = "valid"
-				else
-					session.cert_identity_status = "invalid"
-				end
-				(session.log or log)("debug", "certificate identity validation result: %s", session.cert_identity_status);
-			end
-		end
-	end
 	return module:fire_event("s2s-check-certificate", { host = host, session = session, cert = cert });
 end
 
diff --git a/plugins/mod_s2s_auth_certs.lua b/plugins/mod_s2s_auth_certs.lua
new file mode 100644
index 00000000..be81f51b
--- /dev/null
+++ b/plugins/mod_s2s_auth_certs.lua
@@ -0,0 +1,45 @@
+module:set_global();
+
+local cert_verify_identity = require "util.x509".verify_identity;
+local NULL = {};
+local log = module._log;
+
+module:hook("s2s-check-certificate", function(event)
+	local session, host, cert = event.session, event.host, event.cert;
+	local conn = session.conn:socket();
+
+	if cert then
+		local chain_valid, errors;
+		if conn.getpeerverification then
+			chain_valid, errors = conn:getpeerverification();
+		elseif conn.getpeerchainvalid then -- COMPAT mw/luasec-hg
+			chain_valid, errors = conn:getpeerchainvalid();
+			errors = (not chain_valid) and { { errors } } or nil;
+		else
+			chain_valid, errors = false, { { "Chain verification not supported by this version of LuaSec" } };
+		end
+		-- Is there any interest in printing out all/the number of errors here?
+		if not chain_valid then
+			(session.log or log)("debug", "certificate chain validation result: invalid");
+			for depth, t in pairs(errors or NULL) do
+				(session.log or log)("debug", "certificate error(s) at depth %d: %s", depth-1, table.concat(t, ", "))
+			end
+			session.cert_chain_status = "invalid";
+		else
+			(session.log or log)("debug", "certificate chain validation result: valid");
+			session.cert_chain_status = "valid";
+
+			-- We'll go ahead and verify the asserted identity if the
+			-- connecting server specified one.
+			if host then
+				if cert_verify_identity(host, "xmpp-server", cert) then
+					session.cert_identity_status = "valid"
+				else
+					session.cert_identity_status = "invalid"
+				end
+				(session.log or log)("debug", "certificate identity validation result: %s", session.cert_identity_status);
+			end
+		end
+	end
+end, 509);
+