Update key manager hasher labels

tari-project · May 7, 2024 · 7ed5d94 · 7ed5d94
1 parent 4033f07
commit 7ed5d94
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Showing 2 changed files with 15 additions and 14 deletions.
diff --git a/base_layer/key_manager/src/cipher_seed.rs b/base_layer/key_manager/src/cipher_seed.rs
@@ -45,17 +45,18 @@ use crate::{
     CipherSeedEncryptionKey,
     CipherSeedMacKey,
     SeedWords,
-    LABEL_ARGON_ENCODING,
-    LABEL_CHACHA20_ENCODING,
-    LABEL_MAC_GENERATION,
+    HASHER_LABEL_CIPHER_SEED_ENCRYPTION_NONCE,
+    HASHER_LABEL_CIPHER_SEED_MAC,
+    HASHER_LABEL_CIPHER_SEED_PBKDF_SALT,
 };
 
 // The version should be incremented for any breaking change to the format
 // NOTE: Only the most recent version is supported!
 // History:
 // 0: initial version
 // 1: fixed incorrect key derivation and birthday genesis
-const CIPHER_SEED_VERSION: u8 = 1u8;
+// 2: updated hasher domain labels and MAC input ordering
+const CIPHER_SEED_VERSION: u8 = 2u8;
 
 pub const BIRTHDAY_GENESIS_FROM_UNIX_EPOCH: u64 = 1640995200; // seconds to 2022-01-01 00:00:00 UTC
 pub const DEFAULT_CIPHER_SEED_PASSPHRASE: &str = "TARI_CIPHER_SEED"; // the default passphrase if none is supplied
@@ -180,9 +181,9 @@ impl CipherSeed {
 
         // Generate the MAC
         let mac = Self::generate_mac(
+            CIPHER_SEED_VERSION,
             &self.birthday.to_le_bytes(),
             self.entropy.as_ref(),
-            CIPHER_SEED_VERSION,
             self.salt.as_ref(),
             &mac_key,
         )?;
@@ -279,7 +280,7 @@ impl CipherSeed {
         let birthday = u16::from_le_bytes(birthday_bytes);
 
         // Generate the MAC
-        let expected_mac = Self::generate_mac(&birthday_bytes, entropy.reveal(), version, salt.as_ref(), &mac_key)?;
+        let expected_mac = Self::generate_mac(version, &birthday_bytes, entropy.reveal(), salt.as_ref(), &mac_key)?;
 
         // Verify the MAC in constant time to avoid leaking data
         if mac.ct_eq(&expected_mac).into() {
@@ -301,7 +302,7 @@ impl CipherSeed {
         salt: &[u8],
     ) -> Result<(), KeyManagerError> {
         // The ChaCha20 nonce is derived from the main salt
-        let encryption_nonce = mac_domain_hasher::<Blake2b<U32>>(LABEL_CHACHA20_ENCODING)
+        let encryption_nonce = mac_domain_hasher::<Blake2b<U32>>(HASHER_LABEL_CIPHER_SEED_ENCRYPTION_NONCE)
             .chain(salt)
             .finalize();
         let encryption_nonce = &encryption_nonce.as_ref()[..size_of::<Nonce>()];
@@ -330,9 +331,9 @@ impl CipherSeed {
 
     /// Generate a MAC using Blake2b
     fn generate_mac(
+        version: u8,
         birthday: &[u8],
         entropy: &[u8],
-        cipher_seed_version: u8,
         salt: &[u8],
         mac_key: &CipherSeedMacKey,
     ) -> Result<Vec<u8>, KeyManagerError> {
@@ -347,10 +348,10 @@ impl CipherSeed {
             return Err(KeyManagerError::InvalidData);
         }
 
-        Ok(mac_domain_hasher::<Blake2b<U32>>(LABEL_MAC_GENERATION)
+        Ok(mac_domain_hasher::<Blake2b<U32>>(HASHER_LABEL_CIPHER_SEED_MAC)
+            .chain([version])
             .chain(birthday)
             .chain(entropy)
-            .chain([cipher_seed_version])
             .chain(salt)
             .chain(mac_key.reveal())
             .finalize()
@@ -361,7 +362,7 @@ impl CipherSeed {
     /// Use Argon2 to derive encryption and MAC keys from a passphrase and main salt
     fn derive_keys(passphrase: &SafePassword, salt: &[u8]) -> DerivedCipherSeedKeys {
         // The Argon2 salt is derived from the main salt
-        let argon2_salt = mac_domain_hasher::<Blake2b<U32>>(LABEL_ARGON_ENCODING)
+        let argon2_salt = mac_domain_hasher::<Blake2b<U32>>(HASHER_LABEL_CIPHER_SEED_PBKDF_SALT)
             .chain(salt)
             .finalize();
         let argon2_salt = &argon2_salt.as_ref()[..ARGON2_SALT_BYTES];

diff --git a/base_layer/key_manager/src/lib.rs b/base_layer/key_manager/src/lib.rs
@@ -30,9 +30,9 @@ pub mod schema;
 
 hash_domain!(KeyManagerDomain, "com.tari.base_layer.key_manager", 1);
 
-const LABEL_ARGON_ENCODING: &str = "argon2_encoding";
-const LABEL_CHACHA20_ENCODING: &str = "chacha20_encoding";
-const LABEL_MAC_GENERATION: &str = "mac_generation";
+const HASHER_LABEL_CIPHER_SEED_PBKDF_SALT: &str = "cipher_seed_pbkdf_salt";
+const HASHER_LABEL_CIPHER_SEED_ENCRYPTION_NONCE: &str = "cipher_seed_encryption_nonce";
+const HASHER_LABEL_CIPHER_SEED_MAC: &str = "cipher_seed_mac";
 const LABEL_DERIVE_KEY: &str = "derive_key";
 
 pub(crate) fn mac_domain_hasher<D: Digest + LengthExtensionAttackResistant>(