Merge branch 'main' into upgrade-deps6

.woodpecker.yml

@@ -1,5 +1,6 @@
 variables:
   - &rust_image "rust:1.84-bullseye"
+  - &install_binstall "wget -O- https://github.com/cargo-bins/cargo-binstall/releases/latest/download/cargo-binstall-x86_64-unknown-linux-musl.tgz | tar -xvz -C /usr/local/cargo/bin"
 
 steps:
   cargo_fmt:
@@ -10,7 +11,7 @@ steps:
       - event: pull_request
 
   cargo_shear:
-    image: *rust_nightly_image
+    image: *rust_image
     commands:
       - *install_binstall
       - cargo binstall -y cargo-shear

src/protocol/verification.rs

@@ -1,6 +1,7 @@
 //! Verify that received data is valid
 
-use crate::error::Error;
+use crate::{config::Data, error::Error, fetch::object_id::ObjectId, traits::Object};
+use serde::Deserialize;
 use url::Url;
 
 /// Check that both urls have the same domain. If not, return UrlVerificationError.
@@ -36,3 +37,38 @@ pub fn verify_urls_match(a: &Url, b: &Url) -> Result<(), Error> {
     }
     Ok(())
 }
+
+/// Check that the given ID doesn't match the local domain.
+///
+/// It is important to verify this to avoid local objects from being overwritten. In general
+/// locally created objects should be considered authorative, while incoming federated data
+/// is untrusted. Lack of such a check could allow an attacker to rewrite local posts. It could
+/// also result in an `object.local` field being overwritten with `false` for local objects, resulting in invalid data.
+///
+/// ```
+/// # use activitypub_federation::fetch::object_id::ObjectId;
+/// # use activitypub_federation::config::FederationConfig;
+/// # use activitypub_federation::protocol::verification::verify_is_remote_object;
+/// # use activitypub_federation::traits::tests::{DbConnection, DbUser};
+/// # tokio::runtime::Runtime::new().unwrap().block_on(async {
+/// # let config = FederationConfig::builder().domain("example.com").app_data(DbConnection).build().await?;
+/// # let data = config.to_request_data();
+/// let id = ObjectId::<DbUser>::parse("https://remote.com/u/name")?;
+/// assert!(verify_is_remote_object(&id, &data).is_ok());
+/// # Ok::<(), anyhow::Error>(())
+/// # }).unwrap();
+/// ```
+pub fn verify_is_remote_object<Kind, R: Clone>(
+    id: &ObjectId<Kind>,
+    data: &Data<<Kind as Object>::DataType>,
+) -> Result<(), Error>
+where
+    Kind: Object<DataType = R> + Send + 'static,
+    for<'de2> <Kind as Object>::Kind: Deserialize<'de2>,
+{
+    if id.is_local(data) {
+        Err(Error::UrlVerificationError("Object is not remote"))
+    } else {
+        Ok(())
+    }
+}