use self::following::send_follow_community; use crate::{ activities::{ deletion::{send_apub_delete_in_community, DeletableObjects}, voting::send_like_activity, }, objects::{community::ApubCommunity, person::ApubPerson}, protocol::activities::{ create_or_update::{note::CreateOrUpdateNote, page::CreateOrUpdatePage}, CreateOrUpdateType, }, CONTEXT, }; use activitypub_federation::{ activity_queue::send_activity, config::Data, fetch::object_id::ObjectId, kinds::public, protocol::context::WithContext, traits::{ActivityHandler, Actor}, }; use anyhow::anyhow; use lemmy_api_common::{ context::LemmyContext, send_activity::{ActivityChannel, SendActivityData}, }; use lemmy_db_schema::{ newtypes::CommunityId, source::{ activity::{SentActivity, SentActivityForm}, community::Community, instance::Instance, }, }; use lemmy_db_views_actor::structs::{CommunityPersonBanView, CommunityView}; use lemmy_utils::{ error::{LemmyError, LemmyErrorExt, LemmyErrorType, LemmyResult}, spawn_try_task, SYNCHRONOUS_FEDERATION, }; use moka::future::Cache; use once_cell::sync::Lazy; use serde::Serialize; use std::{ops::Deref, sync::Arc, time::Duration}; use tracing::info; use url::{ParseError, Url}; use uuid::Uuid; pub mod block; pub mod community; pub mod create_or_update; pub mod deletion; pub mod following; pub mod unfederated; pub mod voting; /// Amount of time that the list of dead instances is cached. This is only updated once a day, /// so there is no harm in caching it for a longer time. pub static DEAD_INSTANCE_LIST_CACHE_DURATION: Duration = Duration::from_secs(30 * 60); /// Checks that the specified Url actually identifies a Person (by fetching it), and that the person /// doesn't have a site ban. #[tracing::instrument(skip_all)] async fn verify_person( person_id: &ObjectId, context: &Data, ) -> Result<(), LemmyError> { let person = person_id.dereference(context).await?; if person.banned { return Err(anyhow!("Person {} is banned", person_id)) .with_lemmy_type(LemmyErrorType::CouldntUpdateComment); } Ok(()) } /// Fetches the person and community to verify their type, then checks if person is banned from site /// or community. #[tracing::instrument(skip_all)] pub(crate) async fn verify_person_in_community( person_id: &ObjectId, community: &ApubCommunity, context: &Data, ) -> Result<(), LemmyError> { let person = person_id.dereference(context).await?; if person.banned { return Err(LemmyErrorType::PersonIsBannedFromSite)?; } let person_id = person.id; let community_id = community.id; let is_banned = CommunityPersonBanView::get(&mut context.pool(), person_id, community_id) .await .is_ok(); if is_banned { return Err(LemmyErrorType::PersonIsBannedFromCommunity)?; } Ok(()) } /// Verify that mod action in community was performed by a moderator. /// /// * `mod_id` - Activitypub ID of the mod or admin who performed the action /// * `object_id` - Activitypub ID of the actor or object that is being moderated /// * `community` - The community inside which moderation is happening #[tracing::instrument(skip_all)] pub(crate) async fn verify_mod_action( mod_id: &ObjectId, object_id: &Url, community_id: CommunityId, context: &Data, ) -> Result<(), LemmyError> { let mod_ = mod_id.dereference(context).await?; let is_mod_or_admin = CommunityView::is_mod_or_admin(&mut context.pool(), mod_.id, community_id).await?; if is_mod_or_admin { return Ok(()); } // mod action comes from the same instance as the moderated object, so it was presumably done // by an instance admin. // TODO: federate instance admin status and check it here if mod_id.inner().domain() == object_id.domain() { return Ok(()); } Err(LemmyErrorType::NotAModerator)? } pub(crate) fn verify_is_public(to: &[Url], cc: &[Url]) -> Result<(), LemmyError> { if ![to, cc].iter().any(|set| set.contains(&public())) { return Err(LemmyErrorType::ObjectIsNotPublic)?; } Ok(()) } pub(crate) fn verify_community_matches( a: &ObjectId, b: T, ) -> Result<(), LemmyError> where T: Into>, { let b: ObjectId = b.into(); if a != &b { return Err(LemmyErrorType::InvalidCommunity)?; } Ok(()) } pub(crate) fn check_community_deleted_or_removed(community: &Community) -> Result<(), LemmyError> { if community.deleted || community.removed { Err(LemmyErrorType::CannotCreatePostOrCommentInDeletedOrRemovedCommunity)? } else { Ok(()) } } /// Generate a unique ID for an activity, in the format: /// `http(s)://example.com/receive/create/202daf0a-1489-45df-8d2e-c8a3173fed36` fn generate_activity_id(kind: T, protocol_and_hostname: &str) -> Result where T: ToString, { let id = format!( "{}/activities/{}/{}", protocol_and_hostname, kind.to_string().to_lowercase(), Uuid::new_v4() ); Url::parse(&id) } #[tracing::instrument(skip_all)] async fn send_lemmy_activity( data: &Data, activity: Activity, actor: &ActorT, mut inbox: Vec, sensitive: bool, ) -> Result<(), LemmyError> where Activity: ActivityHandler + Serialize + Send + Sync + Clone, ActorT: Actor, Activity: ActivityHandler, { static CACHE: Lazy>>> = Lazy::new(|| { Cache::builder() .max_capacity(1) .time_to_live(DEAD_INSTANCE_LIST_CACHE_DURATION) .build() }); let dead_instances = CACHE .try_get_with((), async { Ok::<_, diesel::result::Error>(Arc::new(Instance::dead_instances(&mut data.pool()).await?)) }) .await?; inbox.retain(|i| { let domain = i.domain().expect("has domain").to_string(); !dead_instances.contains(&domain) }); info!("Sending activity {}", activity.id().to_string()); let activity = WithContext::new(activity, CONTEXT.deref().clone()); let form = SentActivityForm { ap_id: activity.id().clone().into(), data: serde_json::to_value(activity.clone())?, sensitive, }; SentActivity::create(&mut data.pool(), form).await?; send_activity(activity, actor, inbox, data).await?; Ok(()) } pub async fn handle_outgoing_activities(context: Data) -> LemmyResult<()> { while let Some(data) = ActivityChannel::retrieve_activity().await { match_outgoing_activities(data, &context.reset_request_count()).await? } Ok(()) } pub async fn match_outgoing_activities( data: SendActivityData, context: &Data, ) -> LemmyResult<()> { let context = context.reset_request_count(); let fed_task = async { use SendActivityData::*; match data { CreatePost(post) | UpdatePost(post) => { let creator_id = post.creator_id; CreateOrUpdatePage::send(post, creator_id, CreateOrUpdateType::Create, context).await } CreateComment(comment) | UpdateComment(comment) => { let creator_id = comment.creator_id; CreateOrUpdateNote::send(comment, creator_id, CreateOrUpdateType::Create, context).await } DeleteComment(comment, actor, community) => { let is_deleted = comment.deleted; let deletable = DeletableObjects::Comment(comment.into()); send_apub_delete_in_community(actor, community, deletable, None, is_deleted, &context).await } RemoveComment(comment, actor, community, reason) => { let is_removed = comment.removed; let deletable = DeletableObjects::Comment(comment.into()); send_apub_delete_in_community(actor, community, deletable, reason, is_removed, &context) .await } LikePostOrComment(object_id, person, community, score) => { send_like_activity(object_id, person, community, score, context).await } SendActivityData::FollowCommunity(community, person, follow) => { send_follow_community(community, person, follow, &context).await } } }; if *SYNCHRONOUS_FEDERATION { fed_task.await?; } else { spawn_try_task(fed_task); } Ok(()) }