add additional_fields handling to root, timestamp, and snapshot metas

Signed-off-by: Luke Steensen <luke.steensen@gmail.com>

Author: lukesteensen

tuf/src/metadata.rs

@@ -715,6 +715,7 @@ impl RootMetadataBuilder {
             RoleDefinition::new(self.snapshot_threshold, self.snapshot_key_ids)?,
             RoleDefinition::new(self.targets_threshold, self.targets_key_ids)?,
             RoleDefinition::new(self.timestamp_threshold, self.timestamp_key_ids)?,
+            Default::default(),
         )
     }
 
@@ -763,6 +764,7 @@ pub struct RootMetadata {
     snapshot: RoleDefinition<SnapshotMetadata>,
     targets: RoleDefinition<TargetsMetadata>,
     timestamp: RoleDefinition<TimestampMetadata>,
+    additional_fields: HashMap<String, serde_json::Value>,
 }
 
 impl RootMetadata {
@@ -776,6 +778,7 @@ impl RootMetadata {
         snapshot: RoleDefinition<SnapshotMetadata>,
         targets: RoleDefinition<TargetsMetadata>,
         timestamp: RoleDefinition<TimestampMetadata>,
+        additional_fields: HashMap<String, serde_json::Value>,
     ) -> Result<Self> {
         if version < 1 {
             return Err(Error::MetadataVersionMustBeGreaterThanZero(
@@ -792,6 +795,7 @@ impl RootMetadata {
             snapshot,
             targets,
             timestamp,
+            additional_fields,
         })
     }
 
@@ -857,6 +861,11 @@ impl RootMetadata {
     pub fn timestamp(&self) -> &RoleDefinition<TimestampMetadata> {
         &self.timestamp
     }
+
+    /// An immutable reference to any additional fields on the metadata.
+    pub fn additional_fields(&self) -> &HashMap<String, serde_json::Value> {
+        &self.additional_fields
+    }
 }
 
 impl Metadata for RootMetadata {
@@ -1122,7 +1131,12 @@ impl TimestampMetadataBuilder {
 
     /// Construct a new `TimestampMetadata`.
     pub fn build(self) -> Result<TimestampMetadata> {
-        TimestampMetadata::new(self.version, self.expires, self.snapshot)
+        TimestampMetadata::new(
+            self.version,
+            self.expires,
+            self.snapshot,
+            Default::default(),
+        )
     }
 
     /// Construct a new `SignedMetadata<D, TimestampMetadata>`.
@@ -1143,6 +1157,7 @@ pub struct TimestampMetadata {
     version: u32,
     expires: DateTime<Utc>,
     snapshot: MetadataDescription<SnapshotMetadata>,
+    additional_fields: HashMap<String, serde_json::Value>,
 }
 
 impl TimestampMetadata {
@@ -1151,6 +1166,7 @@ impl TimestampMetadata {
         version: u32,
         expires: DateTime<Utc>,
         snapshot: MetadataDescription<SnapshotMetadata>,
+        additional_fields: HashMap<String, serde_json::Value>,
     ) -> Result<Self> {
         if version < 1 {
             return Err(Error::MetadataVersionMustBeGreaterThanZero(
@@ -1162,13 +1178,19 @@ impl TimestampMetadata {
             version,
             expires,
             snapshot,
+            additional_fields,
         })
     }
 
     /// An immutable reference to the snapshot description.
     pub fn snapshot(&self) -> &MetadataDescription<SnapshotMetadata> {
         &self.snapshot
     }
+
+    /// An immutable reference to any additional fields on the metadata.
+    pub fn additional_fields(&self) -> &HashMap<String, serde_json::Value> {
+        &self.additional_fields
+    }
 }
 
 impl Metadata for TimestampMetadata {
@@ -1380,7 +1402,7 @@ impl SnapshotMetadataBuilder {
 
     /// Construct a new `SnapshotMetadata`.
     pub fn build(self) -> Result<SnapshotMetadata> {
-        SnapshotMetadata::new(self.version, self.expires, self.meta)
+        SnapshotMetadata::new(self.version, self.expires, self.meta, Default::default())
     }
 
     /// Construct a new `SignedMetadata<D, SnapshotMetadata>`.
@@ -1417,6 +1439,7 @@ pub struct SnapshotMetadata {
     version: u32,
     expires: DateTime<Utc>,
     meta: HashMap<MetadataPath, MetadataDescription<TargetsMetadata>>,
+    additional_fields: HashMap<String, serde_json::Value>,
 }
 
 impl SnapshotMetadata {
@@ -1425,6 +1448,7 @@ impl SnapshotMetadata {
         version: u32,
         expires: DateTime<Utc>,
         meta: HashMap<MetadataPath, MetadataDescription<TargetsMetadata>>,
+        additional_fields: HashMap<String, serde_json::Value>,
     ) -> Result<Self> {
         if version < 1 {
             return Err(Error::MetadataVersionMustBeGreaterThanZero(
@@ -1436,13 +1460,19 @@ impl SnapshotMetadata {
             version,
             expires,
             meta,
+            additional_fields,
         })
     }
 
     /// An immutable reference to the metadata paths and descriptions.
     pub fn meta(&self) -> &HashMap<MetadataPath, MetadataDescription<TargetsMetadata>> {
         &self.meta
     }
+
+    /// An immutable reference to any additional fields on the metadata.
+    pub fn additional_fields(&self) -> &HashMap<String, serde_json::Value> {
+        &self.additional_fields
+    }
 }
 
 impl Metadata for SnapshotMetadata {

tuf/src/pouf/pouf1/shims.rs

@@ -52,6 +52,8 @@ pub struct RootMetadata {
     #[serde(deserialize_with = "deserialize_reject_duplicates::deserialize")]
     keys: BTreeMap<crypto::KeyId, crypto::PublicKey>,
     roles: RoleDefinitions,
+    #[serde(flatten)]
+    additional_fields: BTreeMap<String, serde_json::Value>,
 }
 
 impl RootMetadata {
@@ -73,6 +75,7 @@ impl RootMetadata {
                 targets: meta.targets().clone(),
                 timestamp: meta.timestamp().clone(),
             },
+            additional_fields: meta.additional_fields().clone().into_iter().collect(),
         })
     }
 
@@ -109,6 +112,7 @@ impl RootMetadata {
             self.roles.snapshot,
             self.roles.targets,
             self.roles.timestamp,
+            self.additional_fields.into_iter().collect(),
         )
     }
 }
@@ -172,6 +176,8 @@ pub struct TimestampMetadata {
     version: u32,
     expires: String,
     meta: TimestampMeta,
+    #[serde(flatten)]
+    additional_fields: BTreeMap<String, serde_json::Value>,
 }
 
 #[derive(Serialize, Deserialize)]
@@ -191,6 +197,7 @@ impl TimestampMetadata {
             meta: TimestampMeta {
                 snapshot: metadata.snapshot().clone(),
             },
+            additional_fields: metadata.additional_fields().clone().into_iter().collect(),
         })
     }
 
@@ -213,6 +220,7 @@ impl TimestampMetadata {
             self.version,
             parse_datetime(&self.expires)?,
             self.meta.snapshot,
+            self.additional_fields.into_iter().collect(),
         )
     }
 }
@@ -226,6 +234,8 @@ pub struct SnapshotMetadata {
     expires: String,
     #[serde(deserialize_with = "deserialize_reject_duplicates::deserialize")]
     meta: BTreeMap<String, metadata::MetadataDescription<metadata::TargetsMetadata>>,
+    #[serde(flatten)]
+    additional_fields: BTreeMap<String, serde_json::Value>,
 }
 
 impl SnapshotMetadata {
@@ -240,6 +250,7 @@ impl SnapshotMetadata {
                 .iter()
                 .map(|(p, d)| (format!("{}.json", p), d.clone()))
                 .collect(),
+            additional_fields: metadata.additional_fields().clone().into_iter().collect(),
         })
     }
 
@@ -277,6 +288,7 @@ impl SnapshotMetadata {
                     Ok((p, d))
                 })
                 .collect::<Result<_>>()?,
+            self.additional_fields.into_iter().collect(),
         )
     }
 }