feat(decode): support decoding mls messages

decode/Cargo.toml

@@ -8,3 +8,4 @@ license = "GPL-3.0-only"
 clap = { version = "4.5.26", features = ["derive"] }
 proteus-wasm = { workspace = true,  features = ["serde"]}
 base64 = { workspace = true }
+openmls = { workspace = true }

decode/README.md

@@ -25,3 +25,49 @@ ProteusPreKeyBundle {
     signature: None,
 }
 ```
+
+### Decode MLS message
+
+```
+decode mls-message AAEAATQAAQAA0T+Dx7aERkqm8jl1oWIAQgpjb25mZXJlbmNlAAAAAHN0YWdpbmcuemluZnJhLmlvAAAAAAAAAEMCAAAAAAACAAMAAAAHQEgwRgIhAOrk4aL0X6mJwCJWyNzKHIr5qXt05gx5FyP4rmcgviyYAiEAmUwSh7zTqTJAifMn/UnAVNjZKR19DukHS6iVkIP64Oo=
+```
+Output:
+```
+MlsMessageIn {
+    version: Mls10,
+    body: PublicMessage(
+        PublicMessageIn {
+            content: FramedContentIn {
+                group_id: GroupId {
+                    value: VLBytes { 0x00010000d13f83c7b684464aa6f23975a16200420a636f6e666572656e63650000000073746167696e672e7a696e6672612e696f },
+                },
+                epoch: GroupEpoch(
+                    67,
+                ),
+                sender: External(
+                    SenderExtensionIndex(
+                        0,
+                    ),
+                ),
+                authenticated_data: VLBytes { b"" },
+                body: Proposal(
+                    Remove(
+                        RemoveProposal {
+                            removed: LeafNodeIndex(
+                                7,
+                            ),
+                        },
+                    ),
+                ),
+            },
+            auth: FramedContentAuthData {
+                signature: Signature {
+                    value: VLBytes { 0x3046022100eae4e1a2f45fa989c02256c8dcca1c8af9a97b74e60c791723f8ae6720be2c98022100994c1287bcd3a9324089f327fd49c054d8d9291d7d0ee9074ba8959083fae0ea },
+                },
+                confirmation_tag: None,
+            },
+            membership_tag: None,
+        },
+    ),
+}
+```

decode/src/main.rs

@@ -1,5 +1,6 @@
 use base64::Engine;
 use clap::{Parser, Subcommand};
+use openmls::prelude::{MlsMessageIn, TlsDeserializeTrait};
 use proteus_wasm::internal::message::SessionTag;
 use proteus_wasm::internal::util::fmt_hex;
 use proteus_wasm::keys::{PreKeyBundle, Signature};
@@ -121,6 +122,8 @@ enum Command {
         /// Base64 encoded proteus message
         message: String,
     },
+    /// Decode a MLS message
+    MlsMessage { message: String },
 }
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
@@ -138,5 +141,11 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
             println!("{:#?}", ProteusEnvelope::from(message));
             Ok(())
         }
+        Command::MlsMessage { message } => {
+            let bytes = base64::prelude::BASE64_STANDARD.decode(message)?;
+            let message = MlsMessageIn::tls_deserialize(&mut bytes.as_slice())?;
+            println!("{message:#?}");
+            Ok(())
+        }
     }
 }