Rework the way 2FA is enabled/disabled (fixes #3309)

crates/api/Cargo.toml

@@ -34,6 +34,7 @@ chrono = { workspace = true }
 url = { workspace = true }
 wav = "1.0.0"
 sitemap-rs = "0.2.0"
+totp-rs = { version = "5.0.2", features = ["gen_secret", "otpauth"] }
 
 [dev-dependencies]
 serial_test = { workspace = true }

crates/api/src/lib.rs

@@ -1,12 +1,13 @@
 use base64::{engine::general_purpose::STANDARD_NO_PAD as base64, Engine};
 use captcha::Captcha;
 use lemmy_api_common::utils::local_site_to_slur_regex;
-use lemmy_db_schema::source::local_site::LocalSite;
+use lemmy_db_schema::source::{local_site::LocalSite, local_user::LocalUser};
 use lemmy_utils::{
-  error::{LemmyError, LemmyErrorExt, LemmyErrorType},
+  error::{LemmyError, LemmyErrorExt, LemmyErrorType, LemmyResult},
   utils::slurs::check_slurs,
 };
 use std::io::Cursor;
+use totp_rs::{Secret, TOTP};
 
 pub mod comment;
 pub mod comment_report;
@@ -135,3 +136,68 @@ mod tests {
     assert_eq!(1, num_deleted);
   }
 }
+
+pub fn check_totp_2fa_valid(
+  local_user: &LocalUser,
+  totp_token: &Option<String>,
+  site_name: &str,
+  username: &str,
+) -> LemmyResult<()> {
+  // Check only if they have a totp_secret in the DB
+  if local_user.totp_2fa_enabled {
+    // Throw an error if their token is missing
+    let token = totp_token
+      .as_deref()
+      .ok_or(LemmyErrorType::MissingTotpToken)?;
+    let secret = local_user
+      .totp_2fa_secret
+      .as_deref()
+      .ok_or(LemmyErrorType::MissingTotpSecret)?;
+
+    let totp = build_totp_2fa(site_name, username, secret)?;
+
+    let check_passed = totp.check_current(token)?;
+    if !check_passed {
+      return Err(LemmyErrorType::IncorrectTotpToken.into());
+    }
+  }
+
+  Ok(())
+}
+
+pub fn generate_totp_2fa_secret() -> String {
+  Secret::generate_secret().to_string()
+}
+
+pub fn build_totp_2fa(site_name: &str, username: &str, secret: &str) -> Result<TOTP, LemmyError> {
+  let sec = Secret::Raw(secret.as_bytes().to_vec());
+  let sec_bytes = sec
+    .to_bytes()
+    .map_err(|_| LemmyErrorType::CouldntParseTotpSecret)?;
+
+  TOTP::new(
+    totp_rs::Algorithm::SHA1,
+    6,
+    1,
+    30,
+    sec_bytes,
+    Some(site_name.to_string()),
+    username.to_string(),
+  )
+  .with_lemmy_type(LemmyErrorType::CouldntGenerateTotp)
+}
+
+#[cfg(test)]
+mod test {
+  #![allow(clippy::unwrap_used)]
+  #![allow(clippy::indexing_slicing)]
+
+  use super::*;
+
+  #[test]
+  fn test_build_totp() {
+    let generated_secret = generate_totp_2fa_secret();
+    let totp = build_totp_2fa("lemmy", "my_name", &generated_secret);
+    assert!(totp.is_ok());
+  }
+}

crates/api/src/local_user/generate_totp_secret.rs

@@ -0,0 +1,47 @@
+use crate::{build_totp_2fa, generate_totp_2fa_secret};
+use activitypub_federation::config::Data;
+use actix_web::web::Json;
+use lemmy_api_common::{
+  context::LemmyContext,
+  person::GenerateTotpSecretResponse,
+  sensitive::Sensitive,
+};
+use lemmy_db_schema::{
+  source::local_user::{LocalUser, LocalUserUpdateForm},
+  traits::Crud,
+};
+use lemmy_db_views::structs::{LocalUserView, SiteView};
+use lemmy_utils::error::{LemmyError, LemmyErrorType};
+
+/// Generate a new secret for two-factor-authentication. Afterwards you need to call [toggle_totp]
+/// to enable it. This can only be called if 2FA is currently disabled.
+#[tracing::instrument(skip(context))]
+pub async fn generate_totp_secret(
+  local_user_view: LocalUserView,
+  context: Data<LemmyContext>,
+) -> Result<Json<GenerateTotpSecretResponse>, LemmyError> {
+  let site_view = SiteView::read_local(&mut context.pool()).await?;
+
+  if local_user_view.local_user.totp_2fa_enabled {
+    return Err(LemmyErrorType::TotpAlreadyEnabled)?;
+  }
+
+  let secret = generate_totp_2fa_secret();
+  let secret_url =
+    build_totp_2fa(&site_view.site.name, &local_user_view.person.name, &secret)?.get_url();
+
+  let local_user_form = LocalUserUpdateForm {
+    totp_2fa_secret: Some(Some(secret)),
+    ..Default::default()
+  };
+  LocalUser::update(
+    &mut context.pool(),
+    local_user_view.local_user.id,
+    &local_user_form,
+  )
+  .await?;
+
+  Ok(Json(GenerateTotpSecretResponse {
+    totp_secret_url: Sensitive::new(secret_url),
+  }))
+}

crates/api/src/local_user/login.rs

@@ -1,3 +1,4 @@
+use crate::check_totp_2fa_valid;
 use actix_web::web::{Data, Json};
 use bcrypt::verify;
 use lemmy_api_common::{
@@ -9,7 +10,6 @@ use lemmy_db_views::structs::{LocalUserView, SiteView};
 use lemmy_utils::{
   claims::Claims,
   error::{LemmyError, LemmyErrorExt, LemmyErrorType},
-  utils::validation::check_totp_2fa_valid,
 };
 
 #[tracing::instrument(skip(context))]
@@ -55,7 +55,7 @@ pub async fn login(
 
   // Check the totp
   check_totp_2fa_valid(
-    &local_user_view.local_user.totp_2fa_secret,
+    &local_user_view.local_user,
     &data.totp_2fa_token,
     &site_view.site.name,
     &local_user_view.person.name,

crates/api/src/local_user/mod.rs

@@ -3,11 +3,13 @@ pub mod ban_person;
 pub mod block;
 pub mod change_password;
 pub mod change_password_after_reset;
+pub mod generate_totp_secret;
 pub mod get_captcha;
 pub mod list_banned;
 pub mod login;
 pub mod notifications;
 pub mod report_count;
 pub mod reset_password;
 pub mod save_settings;
+pub mod toggle_totp;
 pub mod verify_email;

crates/api/src/local_user/save_settings.rs

@@ -17,13 +17,7 @@ use lemmy_db_views::structs::SiteView;
 use lemmy_utils::{
   claims::Claims,
   error::{LemmyError, LemmyErrorExt, LemmyErrorType},
-  utils::validation::{
-    build_totp_2fa,
-    generate_totp_2fa_secret,
-    is_valid_bio_field,
-    is_valid_display_name,
-    is_valid_matrix_id,
-  },
+  utils::validation::{is_valid_bio_field, is_valid_display_name, is_valid_matrix_id},
 };
 
 #[tracing::instrument(skip(context))]
@@ -105,20 +99,6 @@ pub async fn save_user_settings(
     LocalUserLanguage::update(&mut context.pool(), discussion_languages, local_user_id).await?;
   }
 
-  // If generate_totp is Some(false), this will clear it out from the database.
-  let (totp_2fa_secret, totp_2fa_url) = if let Some(generate) = data.generate_totp_2fa {
-    if generate {
-      let secret = generate_totp_2fa_secret();
-      let url =
-        build_totp_2fa(&site_view.site.name, &local_user_view.person.name, &secret)?.get_url();
-      (Some(Some(secret)), Some(Some(url)))
-    } else {
-      (Some(None), Some(None))
-    }
-  } else {
-    (None, None)
-  };
-
   let local_user_form = LocalUserUpdateForm {
     email,
     show_avatars: data.show_avatars,
@@ -134,8 +114,6 @@ pub async fn save_user_settings(
     default_listing_type,
     theme,
     interface_language: data.interface_language.clone(),
-    totp_2fa_secret,
-    totp_2fa_url,
     open_links_in_new_tab: data.open_links_in_new_tab,
     infinite_scroll_enabled: data.infinite_scroll_enabled,
     ..Default::default()

crates/api/src/local_user/toggle_totp.rs

@@ -0,0 +1,61 @@
+use crate::check_totp_2fa_valid;
+use actix_web::{
+  web::{Data, Json},
+  HttpResponse,
+};
+use lemmy_api_common::{context::LemmyContext, person::ToggleTotp};
+use lemmy_db_schema::{
+  source::local_user::{LocalUser, LocalUserUpdateForm},
+  traits::Crud,
+};
+use lemmy_db_views::structs::{LocalUserView, SiteView};
+use lemmy_utils::error::{LemmyError, LemmyErrorType};
+
+/// Enable or disable two-factor-authentication. The current setting is determined from
+/// [LocalUser.totp_2fa_enabled].
+///
+/// To enable, you need to first call [generate_totp_secret] and then pass a valid token to this
+/// function.
+///
+/// Disabling is only possible if 2FA was previously enabled. Again it is necessary to pass a valid
+/// token.
+#[tracing::instrument(skip(context))]
+pub async fn toggle_totp(
+  data: Json<ToggleTotp>,
+  local_user_view: LocalUserView,
+  context: Data<LemmyContext>,
+) -> Result<HttpResponse, LemmyError> {
+  let site_view = SiteView::read_local(&mut context.pool()).await?;
+
+  // require valid 2fa token to enable or disable 2fa
+  if local_user_view.local_user.totp_2fa_secret.is_none() {
+    return Err(LemmyErrorType::MissingTotpToken.into());
+  }
+  check_totp_2fa_valid(
+    &local_user_view.local_user,
+    &Some(data.totp_totp_token.clone()),
+    &site_view.site.name,
+    &local_user_view.person.name,
+  )?;
+
+  // toggle the 2fa setting
+  let new_totp_state = !local_user_view.local_user.totp_2fa_enabled;
+  let mut local_user_form = LocalUserUpdateForm {
+    totp_2fa_enabled: Some(new_totp_state),
+    ..Default::default()
+  };
+
+  // clear totp secret if 2fa is being disabled
+  if !new_totp_state {
+    local_user_form.totp_2fa_secret = None;
+  }
+
+  LocalUser::update(
+    &mut context.pool(),
+    local_user_view.local_user.id,
+    &local_user_form,
+  )
+  .await?;
+
+  Ok(HttpResponse::Ok().finish())
+}

crates/api_common/src/person.rs

@@ -119,10 +119,6 @@ pub struct SaveUserSettings {
   pub show_new_post_notifs: Option<bool>,
   /// A list of languages you are able to see discussion in.
   pub discussion_languages: Option<Vec<LanguageId>>,
-  /// Generates a TOTP / 2-factor authentication token.
-  ///
-  /// None leaves it as is, true will generate or regenerate it, false clears it out.
-  pub generate_totp_2fa: Option<bool>,
   pub auth: Sensitive<String>,
   /// Open links in a new tab
   pub open_links_in_new_tab: Option<bool>,
@@ -443,3 +439,17 @@ pub struct VerifyEmail {
 #[cfg_attr(feature = "full", ts(export))]
 /// A response to verifying your email.
 pub struct VerifyEmailResponse {}
+
+#[derive(Debug, Serialize, Deserialize, Clone)]
+#[cfg_attr(feature = "full", derive(TS))]
+#[cfg_attr(feature = "full", ts(export))]
+pub struct GenerateTotpSecretResponse {
+  pub totp_secret_url: Sensitive<String>,
+}
+
+#[derive(Debug, Serialize, Deserialize, Clone)]
+#[cfg_attr(feature = "full", derive(TS))]
+#[cfg_attr(feature = "full", ts(export))]
+pub struct ToggleTotp {
+  pub totp_totp_token: String,
+}

crates/db_schema/src/schema.rs

@@ -427,13 +427,13 @@ diesel::table! {
         email_verified -> Bool,
         accepted_application -> Bool,
         totp_2fa_secret -> Nullable<Text>,
-        totp_2fa_url -> Nullable<Text>,
         open_links_in_new_tab -> Bool,
         blur_nsfw -> Bool,
         auto_expand -> Bool,
         infinite_scroll_enabled -> Bool,
         admin -> Bool,
         post_listing_mode -> PostListingModeEnum,
+        totp_2fa_enabled -> Bool,
     }
 }
 

crates/db_schema/src/source/local_user.rs

@@ -51,8 +51,6 @@ pub struct LocalUser {
   pub accepted_application: bool,
   #[serde(skip)]
   pub totp_2fa_secret: Option<String>,
-  /// A URL to add their 2-factor auth.
-  pub totp_2fa_url: Option<String>,
   /// Open links in a new tab.
   pub open_links_in_new_tab: bool,
   pub blur_nsfw: bool,
@@ -62,6 +60,7 @@ pub struct LocalUser {
   /// Whether the person is an admin.
   pub admin: bool,
   pub post_listing_mode: PostListingMode,
+  pub totp_2fa_enabled: bool,
 }
 
 #[derive(Clone, TypedBuilder)]
@@ -88,13 +87,13 @@ pub struct LocalUserInsertForm {
   pub email_verified: Option<bool>,
   pub accepted_application: Option<bool>,
   pub totp_2fa_secret: Option<Option<String>>,
-  pub totp_2fa_url: Option<Option<String>>,
   pub open_links_in_new_tab: Option<bool>,
   pub blur_nsfw: Option<bool>,
   pub auto_expand: Option<bool>,
   pub infinite_scroll_enabled: Option<bool>,
   pub admin: Option<bool>,
   pub post_listing_mode: Option<PostListingMode>,
+  pub totp_2fa_enabled: Option<bool>,
 }
 
 #[derive(Clone, Default)]
@@ -117,11 +116,11 @@ pub struct LocalUserUpdateForm {
   pub email_verified: Option<bool>,
   pub accepted_application: Option<bool>,
   pub totp_2fa_secret: Option<Option<String>>,
-  pub totp_2fa_url: Option<Option<String>>,
   pub open_links_in_new_tab: Option<bool>,
   pub blur_nsfw: Option<bool>,
   pub auto_expand: Option<bool>,
   pub infinite_scroll_enabled: Option<bool>,
   pub admin: Option<bool>,
   pub post_listing_mode: Option<PostListingMode>,
+  pub totp_2fa_enabled: Option<bool>,
 }