From dcf8e53cd427fbd1bebdbf16f43725c58387be2a Mon Sep 17 00:00:00 2001
From: Dark <7890309+DarkView@users.noreply.github.com>
Date: Fri, 20 Mar 2020 18:04:37 +0100
Subject: [PATCH] Added ability to white or blacklist attachment filetype in
 automod

Intended to allow certain channels (i.e. bug reporting ones) to only allow .log files with uploads enabled, making it impossible to upload mp4s to troll or similar
---
 backend/src/plugins/Automod/Automod.ts | 57 ++++++++++++++++++++++++++
 backend/src/plugins/Automod/types.ts   | 15 +++++++
 2 files changed, 72 insertions(+)

diff --git a/backend/src/plugins/Automod/Automod.ts b/backend/src/plugins/Automod/Automod.ts
index 609cdb83..d6b91400 100644
--- a/backend/src/plugins/Automod/Automod.ts
+++ b/backend/src/plugins/Automod/Automod.ts
@@ -60,10 +60,12 @@ import {
   TMatchWordsTrigger,
   TMemberJoinTrigger,
   TRule,
+  TMatchAttachmentTypeTrigger,
 } from "./types";
 import { pluginInfo } from "./info";
 import { ERRORS, RecoverablePluginError } from "../../RecoverablePluginError";
 import Timeout = NodeJS.Timeout;
+import { StrictValidationError } from "src/validatorUtils";
 
 const unactioned = (action: TextRecentAction | OtherRecentAction) => !action.actioned;
 
@@ -116,6 +118,19 @@ const defaultMatchLinksTrigger: Partial<TMatchLinksTrigger> = {
   match_custom_status: false,
 };
 
+const defaultMatchAttachmentTypeTrigger: Partial<TMatchAttachmentTypeTrigger> = {
+  filetype_blacklist: [],
+  blacklist_enabled: false,
+  filetype_whitelist: [],
+  whitelist_enabled: false,
+  match_messages: true,
+  match_embeds: true,
+  match_visible_names: false,
+  match_usernames: false,
+  match_nicknames: false,
+  match_custom_status: false,
+};
+
 const defaultTextSpamTrigger: Partial<t.TypeOf<typeof BaseTextSpamTrigger>> = {
   per_channel: true,
 };
@@ -130,6 +145,7 @@ const defaultTriggers = {
   match_regex: defaultMatchRegexTrigger,
   match_invites: defaultMatchInvitesTrigger,
   match_links: defaultMatchLinksTrigger,
+  match_attachment_type: defaultMatchAttachmentTypeTrigger,
   message_spam: defaultTextSpamTrigger,
   mention_spam: defaultTextSpamTrigger,
   link_spam: defaultTextSpamTrigger,
@@ -249,6 +265,21 @@ export class AutomodPlugin extends ZeppelinPlugin<TConfigSchema, ICustomOverride
                 trigger[defaultTriggerName] = configUtils.mergeConfig({}, defaultTrigger, trigger[defaultTriggerName]);
               }
             }
+
+            if (trigger.match_attachment_type) {
+              const white = trigger.match_attachment_type.whitelist_enabled;
+              const black = trigger.match_attachment_type.blacklist_enabled;
+
+              if (white && black) {
+                throw new StrictValidationError([
+                  `Cannot have both blacklist and whitelist enabled at rule <${rule.name}/match_attachment_type>`,
+                ]);
+              } else if (!white && !black) {
+                throw new StrictValidationError([
+                  `Must have either blacklist or whitelist enabled at rule <${rule.name}/match_attachment_type>`,
+                ]);
+              }
+            }
           }
         }
 
@@ -457,6 +488,23 @@ export class AutomodPlugin extends ZeppelinPlugin<TConfigSchema, ICustomOverride
     return null;
   }
 
+  protected evaluateMatchAttachmentTypeTrigger(trigger: TMatchAttachmentTypeTrigger, msg: SavedMessage): null | string {
+    if (!msg.data.attachments) return null;
+    const attachments: any[] = msg.data.attachments;
+
+    for (const attachment of attachments) {
+      const attachment_type = attachment.filename.split(`.`).pop();
+      if (trigger.blacklist_enabled && trigger.filetype_blacklist.includes(attachment_type)) {
+        return `${attachment_type} - blacklisted`;
+      }
+      if (trigger.whitelist_enabled && !trigger.filetype_whitelist.includes(attachment_type)) {
+        return `${attachment_type} - not whitelisted`;
+      }
+    }
+
+    return null;
+  }
+
   protected matchTextSpamTrigger(
     recentActionType: RecentActionType,
     trigger: TBaseTextSpamTrigger,
@@ -626,6 +674,13 @@ export class AutomodPlugin extends ZeppelinPlugin<TConfigSchema, ICustomOverride
         if (match) return { ...match, trigger: "match_links" } as TextTriggerMatchResult;
       }
 
+      if (trigger.match_attachment_type) {
+        const match = await this.matchMultipleTextTypesOnMessage(trigger.match_attachment_type, msg, str => {
+          return this.evaluateMatchAttachmentTypeTrigger(trigger.match_attachment_type, msg);
+        });
+        if (match) return { ...match, trigger: "match_attachment_type" } as TextTriggerMatchResult;
+      }
+
       if (trigger.message_spam) {
         const match = this.matchTextSpamTrigger(RecentActionType.Message, trigger.message_spam, msg);
         if (match) return { ...match, rule, trigger: "message_spam" };
@@ -1319,6 +1374,8 @@ export class AutomodPlugin extends ZeppelinPlugin<TConfigSchema, ICustomOverride
       return `invite code \`${disableInlineCode(matchResult.matchedValue)}\``;
     } else if (matchResult.trigger === "match_links") {
       return `link \`${disableInlineCode(matchResult.matchedValue)}\``;
+    } else if (matchResult.trigger === "match_attachment_type") {
+      return `attachment type \`${disableInlineCode(matchResult.matchedValue)}\``;
     }
 
     return typeof matchResult.matchedValue === "string" ? `\`${disableInlineCode(matchResult.matchedValue)}\`` : null;
diff --git a/backend/src/plugins/Automod/types.ts b/backend/src/plugins/Automod/types.ts
index c43a21d1..45a6c05b 100644
--- a/backend/src/plugins/Automod/types.ts
+++ b/backend/src/plugins/Automod/types.ts
@@ -179,6 +179,20 @@ export const MatchLinksTrigger = t.type({
 });
 export type TMatchLinksTrigger = t.TypeOf<typeof MatchLinksTrigger>;
 
+export const MatchAttachmentTypeTrigger = t.type({
+  filetype_blacklist: t.array(t.string),
+  blacklist_enabled: t.boolean,
+  filetype_whitelist: t.array(t.string),
+  whitelist_enabled: t.boolean,
+  match_messages: t.boolean,
+  match_embeds: t.boolean,
+  match_visible_names: t.boolean,
+  match_usernames: t.boolean,
+  match_nicknames: t.boolean,
+  match_custom_status: t.boolean,
+});
+export type TMatchAttachmentTypeTrigger = t.TypeOf<typeof MatchAttachmentTypeTrigger>;
+
 export const BaseSpamTrigger = t.type({
   amount: t.number,
   within: t.string,
@@ -280,6 +294,7 @@ export const Rule = t.type({
       match_regex: tNullable(MatchRegexTrigger),
       match_invites: tNullable(MatchInvitesTrigger),
       match_links: tNullable(MatchLinksTrigger),
+      match_attachment_type: tNullable(MatchAttachmentTypeTrigger),
       message_spam: tNullable(MessageSpamTrigger),
       mention_spam: tNullable(MentionSpamTrigger),
       link_spam: tNullable(LinkSpamTrigger),