From c9983b8dcb0654716a9bdf9f2ea0db21c55c8bab Mon Sep 17 00:00:00 2001
From: trisua <me@trisua.com>
Date: Mon, 2 Jun 2025 16:36:06 -0400
Subject: [PATCH] add: ability to ban strings/characters through server config

---
 crates/core/src/config.rs         | 22 ++++++++++++++++++++++
 crates/core/src/database/posts.rs | 20 ++++++++++++++++++++
 example/tetratto.toml             |  6 ++++++
 3 files changed, 48 insertions(+)

diff --git a/crates/core/src/config.rs b/crates/core/src/config.rs
index d1789e7..c0dece2 100644
--- a/crates/core/src/config.rs
+++ b/crates/core/src/config.rs
@@ -211,6 +211,20 @@ impl Default for ManualsConfig {
     }
 }
 
+#[derive(Clone, Serialize, Deserialize, Debug, PartialEq, Eq)]
+pub enum StringBan {
+    /// An exact string.
+    String(String),
+    /// A unicode codepoint.
+    Unicode(u32),
+}
+
+impl Default for StringBan {
+    fn default() -> Self {
+        Self::String(String::new())
+    }
+}
+
 /// Configuration file
 #[derive(Clone, Serialize, Deserialize, Debug)]
 pub struct Config {
@@ -277,6 +291,9 @@ pub struct Config {
     /// The relative paths to manuals.
     #[serde(default)]
     pub manuals: ManualsConfig,
+    /// A list of banned content in posts.
+    #[serde(default)]
+    pub banned_data: Vec<StringBan>,
 }
 
 fn default_name() -> String {
@@ -353,6 +370,10 @@ fn default_manuals() -> ManualsConfig {
     ManualsConfig::default()
 }
 
+fn default_banned_data() -> Vec<StringBan> {
+    Vec::new()
+}
+
 impl Default for Config {
     fn default() -> Self {
         Self {
@@ -374,6 +395,7 @@ impl Default for Config {
             html_footer_path: String::new(),
             stripe: None,
             manuals: default_manuals(),
+            banned_data: default_banned_data(),
         }
     }
 }
diff --git a/crates/core/src/database/posts.rs b/crates/core/src/database/posts.rs
index b9cc171..55843e2 100644
--- a/crates/core/src/database/posts.rs
+++ b/crates/core/src/database/posts.rs
@@ -1,6 +1,7 @@
 use std::collections::HashMap;
 use super::*;
 use crate::cache::Cache;
+use crate::config::StringBan;
 use crate::model::auth::Notification;
 use crate::model::communities::Question;
 use crate::model::communities_permissions::CommunityPermission;
@@ -1153,6 +1154,25 @@ impl DataManager {
     /// # Arguments
     /// * `data` - a mock [`Post`] object to insert
     pub async fn create_post(&self, mut data: Post) -> Result<usize> {
+        // check characters
+        for ban in &self.0.banned_data {
+            match ban {
+                StringBan::String(x) => {
+                    if data.content.contains(x) {
+                        return Ok(0);
+                    }
+                }
+                StringBan::Unicode(x) => {
+                    if data.content.contains(&match char::from_u32(x.to_owned()) {
+                        Some(c) => c.to_string(),
+                        None => continue,
+                    }) {
+                        return Ok(0);
+                    }
+                }
+            }
+        }
+
         // check values (if this isn't reposting something else)
         let is_reposting = if let Some(ref repost) = data.context.repost {
             repost.reposting.is_some()
diff --git a/example/tetratto.toml b/example/tetratto.toml
index 837924b..37119a4 100644
--- a/example/tetratto.toml
+++ b/example/tetratto.toml
@@ -43,3 +43,9 @@ privacy = "/public/privacy.html"
 [turnstile]
 site_key = "1x00000000000000000000AA"
 secret_key = "1x0000000000000000000000000000000AA"
+
+[[banned_data]]
+String = "test banned string"
+
+[[banned_data]]
+Unicode = 3662