WASM

example-usage/server/src/handlers.rs

@@ -0,0 +1,139 @@
+use mtp::codec::{CommunicationType, CommunicationValue, DataType, DataTypeId, DataValue, TypeMap};
+use mtp::crypto::{ChaCha20Poly1305, CryptoError, SignatureScheme, SignaturePublicKey, verify_ed25519};
+
+struct Ed25519Verifier(SignaturePublicKey);
+
+impl SignatureScheme for Ed25519Verifier {
+    fn sign(&self, _msg: &[u8]) -> Result<Vec<u8>, CryptoError> {
+        Err(CryptoError::SigningFailed)
+    }
+    fn verify(&self, msg: &[u8], signature: &[u8]) -> Result<(), CryptoError> {
+        verify_ed25519(&self.0, msg, signature)
+    }
+}
+
+fn derive_demo_key() -> [u8; 32] {
+    mtp::crypto::derive_encryption_key(
+        b"MTP-demo-shared-secret",
+        b"MTP-demo-salt",
+        b"encrypted-container-demo",
+    )
+    .expect("key derivation must succeed")
+}
+
+pub fn process_and_respond(
+    msg: &CommunicationValue,
+    tm: &TypeMap,
+    client_pk: Option<&mtp::crypto::PublicKeyBundle>,
+) -> CommunicationValue {
+    let desc_id = DataTypeId(tm.data_id_enum(DataType::Description).unwrap());
+    let ts_id = DataTypeId(tm.data_id_enum(DataType::Timestamp).unwrap());
+    let data_id = DataTypeId(tm.data_id_enum(DataType::Data).unwrap());
+    let flags_id = DataTypeId(tm.data_id_enum(DataType::Flags).unwrap());
+    let value_id = DataTypeId(tm.data_id_enum(DataType::Value).unwrap());
+    let bin_id = DataTypeId(tm.data_id_enum(DataType::BinaryData).unwrap());
+    let items_id = DataTypeId(tm.data_id_enum(DataType::Items).unwrap());
+    let enc_id = DataTypeId(tm.data_id_enum(DataType::EncryptedPayload).unwrap());
+    let sig_id = DataTypeId(tm.data_id_enum(DataType::SignedPayload).unwrap());
+    let secure_id = DataTypeId(tm.data_id_enum(DataType::SecurePayload).unwrap());
+
+    let description = msg.get_data(desc_id);
+    let timestamp = msg.get_data(ts_id);
+    let data = msg.get_data(data_id);
+    let flags = msg.get_data(flags_id);
+    let value = msg.get_data(value_id);
+    let binary = msg.get_data(bin_id);
+    let items = msg.get_data(items_id);
+
+    println!(
+        "  Description: {}",
+        description.as_str().unwrap_or("(missing)")
+    );
+    println!("  Timestamp: {:?}", timestamp.as_unsigned_number());
+    println!("  Data: {}", data.as_str().unwrap_or("(missing)"));
+    println!("  Flags: {:?}", flags.as_bool());
+    println!("  Value: {:?}", value.as_float());
+    println!("  Binary: {:?}", binary.as_bytes());
+    println!("  Items: {:?}", items.as_array());
+
+    let cipher = ChaCha20Poly1305::new(derive_demo_key());
+
+    let mut enc_status = String::from("EncryptedPayload: not present");
+    let mut sig_status = String::from("SignedPayload: not present");
+    let mut secure_status = String::from("SecurePayload: not present");
+
+    let enc = msg.get_data(enc_id);
+    if matches!(enc, DataValue::EncryptedContainer(_)) {
+        let mut dv = enc.clone();
+        if dv.decrypt_into_container(&cipher, b"demo-aad").is_some() {
+            if let Some(entries) = dv.as_container() {
+                println!("  Decrypted EncryptedPayload: {:?}", entries);
+                enc_status = format!("EncryptedPayload decrypted OK ({} entries)", entries.len());
+            }
+        } else {
+            enc_status = String::from("EncryptedPayload: decryption FAILED");
+        }
+    }
+
+    let sig = msg.get_data(sig_id);
+    if matches!(sig, DataValue::SignedContainer(_)) {
+        if let Some(pk_bundle) = client_pk {
+            let verifier = Ed25519Verifier(pk_bundle.sig_cl_public_key.clone());
+            let mut dv = sig.clone();
+            if dv.verify_into_container(&verifier).is_some() {
+                if let Some(entries) = dv.as_container() {
+                    println!("  Verified SignedPayload: {:?}", entries);
+                    sig_status =
+                        format!("SignedPayload verified OK ({} entries)", entries.len());
+                }
+            } else {
+                sig_status = String::from("SignedPayload: verification FAILED");
+            }
+        } else {
+            sig_status = String::from("SignedPayload: no client public key available");
+        }
+    }
+
+    let secure = msg.get_data(secure_id);
+    if matches!(secure, DataValue::SignedEncryptedContainer(_)) {
+        if let Some(pk_bundle) = client_pk {
+            let verifier = Ed25519Verifier(pk_bundle.sig_cl_public_key.clone());
+            let mut dv = secure.clone();
+            if dv.decrypt_signed_encrypted_container(&cipher, b"demo-aad").is_some()
+                && dv.verify_into_container(&verifier).is_some()
+            {
+                if let Some(entries) = dv.as_container() {
+                    println!("  Verified SecurePayload: {:?}", entries);
+                    secure_status = format!(
+                        "SecurePayload decrypted+verified OK ({} entries)",
+                        entries.len()
+                    );
+                }
+            } else {
+                secure_status = String::from("SecurePayload: decryption/verification FAILED");
+            }
+        } else {
+            secure_status = String::from("SecurePayload: no client public key available");
+        }
+    }
+
+    let now = std::time::SystemTime::now()
+        .duration_since(std::time::UNIX_EPOCH)
+        .unwrap()
+        .as_secs();
+
+    CommunicationValue::from_comm(CommunicationType::Pong, tm)
+        .add_data(desc_id, description.clone())
+        .add_data(ts_id, DataValue::UnsignedNumber(now as u128))
+        .add_data(
+            data_id,
+            DataValue::Str(format!(
+                "{}. {}. {}.",
+                enc_status, sig_status, secure_status
+            )),
+        )
+        .add_data(flags_id, flags.clone())
+        .add_data(value_id, value.clone())
+        .add_data(bin_id, binary.clone())
+        .add_data(items_id, items.clone())
+}