Move existing captcha logic to plugin (fixes #6148)

Cargo.toml

@@ -176,7 +176,6 @@ chrono = { version = "0.4.42", features = [
 serde_json = { version = "1.0.145", features = ["preserve_order"] }
 base64 = "0.22.1"
 uuid = { version = "1.19.0", features = ["serde"] }
-captcha = "1.0.0"
 anyhow = { version = "1.0.100", features = ["backtrace"] }
 diesel_ltree = "0.4.0"
 serial_test = "3.2.0"

crates/api/api/Cargo.toml

@@ -58,13 +58,10 @@ activitypub_federation = { workspace = true }
 tracing = { workspace = true }
 bcrypt = { workspace = true }
 actix-web = { workspace = true }
-base64 = { workspace = true }
-captcha = { workspace = true }
 anyhow = { workspace = true }
 chrono = { workspace = true }
 url = { workspace = true }
 regex = { workspace = true }
-hound = "3.5.1"
 sitemap-rs = "0.4.0"
 totp-rs = { version = "5.7.0", features = ["gen_secret", "otpauth"] }
 diesel-async = { workspace = true, features = ["deadpool", "postgres"] }

crates/api/api/src/lib.rs

@@ -1,5 +1,3 @@
-use base64::{Engine, engine::general_purpose::STANDARD_NO_PAD as base64};
-use captcha::Captcha;
 use lemmy_api_utils::{context::LemmyContext, utils::is_mod_or_admin_opt};
 use lemmy_db_schema::newtypes::CommunityId;
 use lemmy_db_views_local_user::LocalUserView;
@@ -8,7 +6,6 @@ use lemmy_utils::{
   utils::slurs::check_slurs,
 };
 use regex::Regex;
-use std::io::Cursor;
 use totp_rs::{Secret, TOTP};
 
 pub mod comment;
@@ -20,46 +17,6 @@ pub mod reports;
 pub mod site;
 pub mod sitemap;
 
-/// Converts the captcha to a base64 encoded wav audio file
-pub(crate) fn captcha_as_wav_base64(captcha: &Captcha) -> LemmyResult<String> {
-  let letters = captcha.as_wav();
-
-  // Decode each wav file, concatenate the samples
-  let mut concat_samples: Vec<i16> = Vec::new();
-  let mut any_header: Option<hound::WavSpec> = None;
-  for letter in letters {
-    let mut cursor = Cursor::new(letter.unwrap_or_default());
-    let reader = hound::WavReader::new(&mut cursor)?;
-    any_header = Some(reader.spec());
-    let samples16 = reader
-      .into_samples::<i16>()
-      .collect::<Result<Vec<_>, _>>()
-      .with_lemmy_type(LemmyErrorType::CouldntCreateAudioCaptcha)?;
-    concat_samples.extend(samples16);
-  }
-
-  // Encode the concatenated result as a wav file
-  let mut output_buffer = Cursor::new(vec![]);
-  if let Some(header) = any_header {
-    let mut writer = hound::WavWriter::new(&mut output_buffer, header)
-      .with_lemmy_type(LemmyErrorType::CouldntCreateAudioCaptcha)?;
-    let mut writer16 = writer.get_i16_writer(concat_samples.len().try_into()?);
-    for sample in concat_samples {
-      writer16.write_sample(sample);
-    }
-    writer16
-      .flush()
-      .with_lemmy_type(LemmyErrorType::CouldntCreateAudioCaptcha)?;
-    writer
-      .finalize()
-      .with_lemmy_type(LemmyErrorType::CouldntCreateAudioCaptcha)?;
-
-    Ok(base64.encode(output_buffer.into_inner()))
-  } else {
-    Err(LemmyErrorType::CouldntCreateAudioCaptcha)?
-  }
-}
-
 /// Check size of report
 pub(crate) fn check_report_reason(reason: &str, slur_regex: &Regex) -> LemmyResult<()> {
   check_slurs(reason, slur_regex)?;

crates/api/api/src/local_user/get_captcha.rs

@@ -1,55 +1,26 @@
-use crate::captcha_as_wav_base64;
 use actix_web::{
   HttpResponse,
   HttpResponseBuilder,
   http::{
     StatusCode,
     header::{CacheControl, CacheDirective},
   },
-  web::{Data, Json},
+  web::Json,
 };
-use captcha::{Difficulty, generate};
-use lemmy_api_utils::context::LemmyContext;
-use lemmy_db_schema::source::captcha_answer::{CaptchaAnswer, CaptchaAnswerForm};
-use lemmy_db_views_site::{
-  SiteView,
-  api::{CaptchaResponse, GetCaptchaResponse},
-};
-use lemmy_utils::error::{LemmyErrorType, LemmyResult};
+use lemmy_api_utils::plugins::{is_captcha_plugin_loaded, plugin_get_captcha};
+use lemmy_db_views_site::api::GetCaptchaResponse;
+use lemmy_utils::error::LemmyResult;
 
-pub async fn get_captcha(context: Data<LemmyContext>) -> LemmyResult<HttpResponse> {
-  let local_site = SiteView::read_local(&mut context.pool()).await?.local_site;
+pub async fn get_captcha() -> LemmyResult<HttpResponse> {
   let mut res = HttpResponseBuilder::new(StatusCode::OK);
   res.insert_header(CacheControl(vec![CacheDirective::NoStore]));
 
-  if !local_site.captcha_enabled {
+  if !is_captcha_plugin_loaded() {
     return Ok(res.json(Json(GetCaptchaResponse { ok: None })));
   }
 
-  let captcha = generate(match local_site.captcha_difficulty.as_str() {
-    "easy" => Difficulty::Easy,
-    "hard" => Difficulty::Hard,
-    _ => Difficulty::Medium,
-  });
-
-  let answer = captcha.chars_as_string();
-
-  let png = captcha
-    .as_base64()
-    .ok_or(LemmyErrorType::CouldntCreateImageCaptcha)?;
-
-  let wav = captcha_as_wav_base64(&captcha)?;
-
-  let captcha_form: CaptchaAnswerForm = CaptchaAnswerForm { answer };
-  // Stores the captcha item in the db
-  let captcha = CaptchaAnswer::insert(&mut context.pool(), &captcha_form).await?;
-
-  let json = Json(GetCaptchaResponse {
-    ok: Some(CaptchaResponse {
-      png,
-      wav,
-      uuid: captcha.uuid.to_string(),
-    }),
-  });
-  Ok(res.json(json))
+  let captcha = GetCaptchaResponse {
+    ok: Some(plugin_get_captcha().await?),
+  };
+  Ok(res.json(Json(captcha)))
 }

crates/api/api_common/src/account.rs

@@ -5,7 +5,7 @@ pub use lemmy_db_views_post_comment_combined::PostCommentCombinedView;
 pub use lemmy_db_views_site::api::{DeleteAccount, MyUserInfo, SaveUserSettings};
 pub mod auth {
   pub use lemmy_db_schema::source::login_token::LoginToken;
-  pub use lemmy_db_views_registration_applications::api::Register;
+  pub use lemmy_db_views_registration_applications::api::{CaptchaAnswer, Register};
   pub use lemmy_db_views_site::api::{
     CaptchaResponse,
     ChangePassword,