add debug output to authelia with mitmdump module

docs/redirects.json

@@ -68,6 +68,9 @@
   "blocks-authelia-options-shb.authelia.dcdomain": [
     "blocks-authelia.html#blocks-authelia-options-shb.authelia.dcdomain"
   ],
+  "blocks-authelia-options-shb.authelia.debug": [
+    "blocks-authelia.html#blocks-authelia-options-shb.authelia.debug"
+  ],
   "blocks-authelia-options-shb.authelia.domain": [
     "blocks-authelia.html#blocks-authelia-options-shb.authelia.domain"
   ],
@@ -305,6 +308,9 @@
   "blocks-authelia-tests": [
     "blocks-authelia.html#blocks-authelia-tests"
   ],
+  "blocks-authelia-troubleshooting": [
+    "blocks-authelia.html#blocks-authelia-troubleshooting"
+  ],
   "blocks-lldap": [
     "blocks-lldap.html#blocks-lldap"
   ],

modules/blocks/authelia.nix

@@ -13,6 +13,8 @@ let
   autheliaCfg = config.services.authelia.instances.${fqdn};
 
   inherit (lib) hasPrefix;
+
+  listenPort = if cfg.debug then 9090 else 9091;
 in
 {
   options.shb.authelia = {
@@ -303,6 +305,15 @@ in
       readOnly = true;
       default = { path = "/var/lib/redis-authelia"; };
     };
+
+    debug = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+      description = ''
+        Set logging level to debug and add a mitmdump instance
+        to see exactly what Authelia receives and sends back.
+      '';
+    };
   };
 
   config = lib.mkIf cfg.enable {
@@ -347,7 +358,7 @@ in
         AUTHELIA_NOTIFIER_SMTP_PASSWORD_FILE = lib.mkIf (!(builtins.isString cfg.smtp)) (toString cfg.smtp.password.result.path);
       };
       settings = {
-        server.address = "tcp://127.0.0.1:9091";
+        server.address = "tcp://127.0.0.1:${toString listenPort}";
 
         # Inspired from https://github.com/lldap/lldap/blob/7d1f5abc137821c500de99c94f7579761fc949d8/example_configs/authelia_config.yml
         authentication_backend = {
@@ -446,6 +457,8 @@ in
             address = "tcp://127.0.0.1:9959";
           };
         };
+
+        log.level = if cfg.debug then "debug" else "info";
       };
 
       settingsFiles = [ "/var/lib/authelia-${fqdn}/oidc_clients.yaml" ];
@@ -485,6 +498,8 @@ in
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
         proxy_set_header X-Forwarded-Proto $scheme;
+        proxy_set_header X-Forwarded-Host $http_host;
+        proxy_set_header X-Forwarded-Uri $request_uri;
         proxy_http_version 1.1;
         proxy_set_header Upgrade $http_upgrade;
         proxy_set_header Connection "upgrade";
@@ -513,6 +528,19 @@ in
         '';
     };
 
+    # I would like this to live outside of the Authelia module.
+    # This will require a reverse proxy contract.
+    # Actually, not sure a full reverse proxy contract is needed.
+    shb.mitmdump.instances."authelia-${fqdn}" = lib.mkIf cfg.debug {
+      listenPort = 9091;
+      upstreamPort = 9090;
+      after = [ "authelia-${fqdn}.service" ];
+      enabledAddons = [ config.shb.mitmdump.addons.logger ];
+      extraArgs = [
+        "--set" "verbose_pattern=/api"
+      ];
+    };
+
     services.redis.servers.authelia = {
       enable = true;
       user = autheliaCfg.user;

modules/blocks/authelia/docs/default.md

@@ -6,6 +6,11 @@ This block sets up an [Authelia][] service for Single-Sign On integration.
 
 [Authelia]: https://www.authelia.com/
 
+Compared to the upstream nixpkgs module, this module is tightly integrated
+with SHB which allows easy configuration of SSO with [OIDC integration](#blocks-authelia-shb-oidc)
+or with [forward auth integration](#blocks-authelia-shb-forward-auth)
+as well as some extensive [troubleshooting](#blocks-authelia-troubleshooting) features.
+
 ## Global Setup {#blocks-authelia-global-setup}
 
 Authelia cannot work without SSL and LDAP.
@@ -221,6 +226,19 @@ shb.nginx.vhosts = [
 
 This configuration assumes usage of the [SSL block][].
 
+## Troubleshooting {#blocks-authelia-troubleshooting}
+
+Set the [debug][opt-debug] option to `true` to:
+
+[opt-debug]: #blocks-authelia-options-shb.authelia.debug
+
+- Set logging level to `"debug"`.
+- Add an [shb.mitmdump][] instance in front of Authelia
+  which prints all requests and responses headers and body
+  to the systemd service `mitmdump-authelia-${config.shb.authelia.subdomain}.${config.shb.authelia.domain}.service`.
+
+[shb.mitmdump]: ./blocks-mitmdump.html
+
 ## Tests {#blocks-authelia-tests}
 
 Specific integration tests are defined in [`/test/blocks/authelia.nix`](@REPO@/test/blocks/authelia.nix).

test/blocks/authelia.nix

@@ -15,6 +15,7 @@ in
         ../../modules/blocks/authelia.nix
         ../../modules/blocks/hardcodedsecret.nix
         ../../modules/blocks/lldap.nix
+        ../../modules/blocks/mitmdump.nix
         ../../modules/blocks/postgresql.nix
       ];
 
@@ -109,48 +110,79 @@ in
           ${pkgs.openssl}/bin/openssl genrsa -out $out/private.pem 4096
         '') + "/private.pem";
       };
+
+      specialisation = {
+        withDebug.configuration = {
+          shb.authelia.debug = true;
+        };
+      };
     };
 
-    testScript = { nodes, ... }: ''
+    testScript = { nodes, ... }:
+    let
+      specializations = "${nodes.machine.system.build.toplevel}/specialisation";
+    in
+    ''
     import json
 
     start_all()
-    machine.wait_for_unit("lldap.service")
-    machine.wait_for_unit("authelia-authelia.machine.com.service")
-    machine.wait_for_open_port(9091)
 
-    endpoints = json.loads(machine.succeed("curl -s http://machine.com/.well-known/openid-configuration"))
+    def tests():
-    auth_endpoint = endpoints['authorization_endpoint']
+        machine.wait_for_unit("lldap.service")
+        machine.wait_for_unit("authelia-authelia.machine.com.service")
+        machine.wait_for_open_port(9091)
 
-    machine.succeed(
+        endpoints = json.loads(machine.succeed("curl -s http://machine.com/.well-known/openid-configuration"))
-        "curl -f -s '"
+        auth_endpoint = endpoints['authorization_endpoint']
-        + auth_endpoint
+        print(f"auth_endpoint: {auth_endpoint}")
-        + "?client_id=other"
+        if auth_endpoint != "http://machine.com/api/oidc/authorization":
-        + "&redirect_uri=http://client1.machine.com/redirect"
+            raise Exception("Unexpected auth_endpoint")
-        + "&scope=openid%20profile%20email"
-        + "&response_type=code"
-        + "&state=99999999'"
-    )
 
-    machine.succeed(
+        resp = machine.succeed(
-        "curl -f -s '"
+            "curl -f -s '"
-        + auth_endpoint
+            + auth_endpoint
-        + "?client_id=client1"
+            + "?client_id=other"
-        + "&redirect_uri=http://client1.machine.com/redirect"
+            + "&redirect_uri=http://client1.machine.com/redirect"
-        + "&scope=openid%20profile%20email"
+            + "&scope=openid%20profile%20email"
-        + "&response_type=code"
+            + "&response_type=code"
-        + "&state=11111111'"
+            + "&state=99999999'"
-    )
+        )
+        print(resp)
+        if resp != "":
+            raise Exception("unexpected response")
 
-    machine.succeed(
+        resp = machine.succeed(
-        "curl -f -s '"
+            "curl -f -s '"
-        + auth_endpoint
+            + auth_endpoint
-        + "?client_id=client2"
+            + "?client_id=client1"
-        + "&redirect_uri=http://client2.machine.com/redirect"
+            + "&redirect_uri=http://client1.machine.com/redirect"
-        + "&scope=openid%20profile%20email"
+            + "&scope=openid%20profile%20email"
-        + "&response_type=code"
+            + "&response_type=code"
-        + "&state=22222222'"
+            + "&state=11111111'"
-    )
+        )
+        print(resp)
+        if "Found" not in resp:
+            raise Exception("unexpected response")
+
+        resp = machine.succeed(
+            "curl -f -s '"
+            + auth_endpoint
+            + "?client_id=client2"
+            + "&redirect_uri=http://client2.machine.com/redirect"
+            + "&scope=openid%20profile%20email"
+            + "&response_type=code"
+            + "&state=22222222'"
+        )
+        print(resp)
+        if "Found" not in resp:
+            raise Exception("unexpected response")
+
+    with subtest("no debug"):
+        tests()
+
+    with subtest("with debug"):
+        machine.succeed('${specializations}/withDebug/bin/switch-to-configuration test')
+        tests()
     '';
   };
 }

test/common.nix

@@ -188,10 +188,11 @@ in
     };
     imports = [
       baseImports
-      ../modules/blocks/postgresql.nix
       ../modules/blocks/authelia.nix
-      ../modules/blocks/nginx.nix
       ../modules/blocks/hardcodedsecret.nix
+      ../modules/blocks/mitmdump.nix
+      ../modules/blocks/nginx.nix
+      ../modules/blocks/postgresql.nix
     ];
     config = {
       # HTTP(s) server port.