From fdb3c4aa491a94772fdd53cdf0c1535af64c856f Mon Sep 17 00:00:00 2001
From: Nils Blume <mail@nilsblume.de>
Date: Thu, 31 Aug 2023 09:22:07 +0200
Subject: [PATCH] added optional anonymous login for clients

---
 README.md       |  3 ++-
 src/Config.php  | 22 ++++++++++++++++++++--
 src/Handler.php | 24 ++++++++++++++++--------
 src/Payload.php |  5 ++++-
 4 files changed, 42 insertions(+), 12 deletions(-)

diff --git a/README.md b/README.md
index 4329e5a..ac7d24a 100644
--- a/README.md
+++ b/README.md
@@ -33,6 +33,7 @@ Parameter | Example | Explanation
 `allowCreate` | true/`false` | allows creation of entries if parameter `create=true` in URL
 `restrictDomain` | true / `false` | allows admin to restrict the domain to update to a given value `domain` and/or `host`. See URL parameters for host parameter explanation
 `allowNetcupCreds` | true / `false` | allows the user to pass netcup credentials directly via the URL. URL creds will be preferred if any still exist in .env file
+`allowAnonymous` | true / `false` | allows anonymous login, recommended only if you do not store any credentials and disable logging
 
 * alternatively you can use .configure.sh to create your .env file for you (if you are on a *NIX system)
 
@@ -49,7 +50,7 @@ You can now set `allowCreate=true` in .env and pass `create=true` as URL paramet
 
 Parameter | Example | Explanation
 ---: | :--- | :---
-user | dnsupdater | username to authenticate against this script as defined in .env file
+user | dnsupdater | username to authenticate against this script as defined in .env file. If anonymous login is allowed in .env: `anonymous`
 password | secretpleasechange |password for that user as defined in .env file
 domain | home.example.com | `case A)` If `host` is not specified: the FQDN for your host
 domain | example.com | `case B)` If you want to update the @ or * record
diff --git a/src/Config.php b/src/Config.php
index 42c3ad2..f819f8e 100644
--- a/src/Config.php
+++ b/src/Config.php
@@ -60,6 +60,11 @@ final class Config
      */
     private $allowNetcupCreds = false;
 
+    /**
+     * @var bool
+     */
+    private $allowAnonymous = false;
+
     /**
      * @var bool
      */
@@ -91,8 +96,13 @@ final class Config
     public function isValid()
     {
         return
-            !empty($this->username) &&
-            !empty($this->password) &&
+            (
+                !empty($this->username) &&
+                !empty($this->password)
+            ) ||
+            (
+                $this->isAllowAnonymous()
+            ) &&
             (
                 (
                     !empty($this->apiKey) &&
@@ -202,6 +212,14 @@ final class Config
         return $this->allowNetcupCreds;
     }
 
+    /**
+     * @return bool
+     */
+    public function isAllowAnonymous()
+    {
+        return $this->allowAnonymous;
+    }
+
     /**
      * @return string
      */
diff --git a/src/Handler.php b/src/Handler.php
index 0b4a6af..c3fde67 100644
--- a/src/Handler.php
+++ b/src/Handler.php
@@ -58,14 +58,22 @@ final class Handler
             }
         }
 
-        if (
-            $this->config->getUsername() !== $this->payload->getUser() ||
-            $this->config->getPassword() !== $this->payload->getPassword()
-        ) {
-            if ($this->config->isDebug()) {
-                throw new RuntimeException('credentials invalid');
-            } else {
-                exit("credentials invalid\n");
+        if ($this->config->isAllowAnonymous()) {
+            if ($this->payload->getUser() == 'anonymous') {
+                if ($this->config->isDebug()) {
+                    $this->doLog('anonymous login by client');
+                }
+            }
+        } else {
+            if (
+                $this->config->getUsername() !== $this->payload->getUser() ||
+                $this->config->getPassword() !== $this->payload->getPassword()
+            ) {
+                if ($this->config->isDebug()) {
+                    throw new RuntimeException('credentials invalid');
+                } else {
+                    exit("credentials invalid\n");
+                }
             }
         }
 
diff --git a/src/Payload.php b/src/Payload.php
index 066465d..0fc56d2 100644
--- a/src/Payload.php
+++ b/src/Payload.php
@@ -85,7 +85,10 @@ final class Payload
     {
         return
             !empty($this->user) &&
-            !empty($this->password) &&
+            (
+                $this->user == 'anonymous' ||
+                !empty($this->password)
+            ) &&
             !empty($this->domain) &&
             (
                 (