refactoring CipherSuite to support unknown value

webrtc-rs · Sep 4, 2023 · cfded12 · cfded12
1 parent 20f8399
commit cfded12
Show file tree

Hide file tree

Showing 19 changed files with 190 additions and 169 deletions.
diff --git a/rmls/src/crypto/cipher_suite.rs b/rmls/src/crypto/cipher_suite.rs
@@ -1,6 +1,5 @@
 //! [RFC9420 Sec.5.1](https://www.rfc-editor.org/rfc/rfc9420.html#section-5.1) Cipher Suite specifies
 //! the cryptographic primitives to be used in group key computations.
-use crate::utilities::error::*;
 
 use std::fmt::{Display, Formatter};
 
@@ -18,49 +17,41 @@ pub enum CipherSuite {
     MLS_256_DHKEMP521_AES256GCM_SHA512_P521 = 0x0005,
     MLS_256_DHKEMX448_CHACHA20POLY1305_SHA512_Ed448 = 0x0006,
     MLS_256_DHKEMP384_AES256GCM_SHA384_P384 = 0x0007,
+    Unknown(u16),
 }
 
-impl TryFrom<u16> for CipherSuite {
-    type Error = Error;
-
-    fn try_from(v: u16) -> std::result::Result<Self, Self::Error> {
+impl From<u16> for CipherSuite {
+    fn from(v: u16) -> Self {
         match v {
-            0x0001 => Ok(CipherSuite::MLS_128_DHKEMX25519_AES128GCM_SHA256_Ed25519),
-            0x0002 => Ok(CipherSuite::MLS_128_DHKEMP256_AES128GCM_SHA256_P256),
-            0x0003 => Ok(CipherSuite::MLS_128_DHKEMX25519_CHACHA20POLY1305_SHA256_Ed25519),
-            0x0004 => Ok(CipherSuite::MLS_256_DHKEMX448_AES256GCM_SHA512_Ed448),
-            0x0005 => Ok(CipherSuite::MLS_256_DHKEMP521_AES256GCM_SHA512_P521),
-            0x0006 => Ok(CipherSuite::MLS_256_DHKEMX448_CHACHA20POLY1305_SHA512_Ed448),
-            0x0007 => Ok(CipherSuite::MLS_256_DHKEMP384_AES256GCM_SHA384_P384),
-            _ => Err(Error::InvalidCipherSuiteValue(v)),
+            0x0001 => CipherSuite::MLS_128_DHKEMX25519_AES128GCM_SHA256_Ed25519,
+            0x0002 => CipherSuite::MLS_128_DHKEMP256_AES128GCM_SHA256_P256,
+            0x0003 => CipherSuite::MLS_128_DHKEMX25519_CHACHA20POLY1305_SHA256_Ed25519,
+            0x0004 => CipherSuite::MLS_256_DHKEMX448_AES256GCM_SHA512_Ed448,
+            0x0005 => CipherSuite::MLS_256_DHKEMP521_AES256GCM_SHA512_P521,
+            0x0006 => CipherSuite::MLS_256_DHKEMX448_CHACHA20POLY1305_SHA512_Ed448,
+            0x0007 => CipherSuite::MLS_256_DHKEMP384_AES256GCM_SHA384_P384,
+            _ => CipherSuite::Unknown(v),
         }
     }
 }
 
-impl Display for CipherSuite {
-    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{self:?}")
+impl From<CipherSuite> for u16 {
+    fn from(val: CipherSuite) -> u16 {
+        match val {
+            CipherSuite::MLS_128_DHKEMX25519_AES128GCM_SHA256_Ed25519 => 0x0001,
+            CipherSuite::MLS_128_DHKEMP256_AES128GCM_SHA256_P256 => 0x0002,
+            CipherSuite::MLS_128_DHKEMX25519_CHACHA20POLY1305_SHA256_Ed25519 => 0x0003,
+            CipherSuite::MLS_256_DHKEMX448_AES256GCM_SHA512_Ed448 => 0x0004,
+            CipherSuite::MLS_256_DHKEMP521_AES256GCM_SHA512_P521 => 0x0005,
+            CipherSuite::MLS_256_DHKEMX448_CHACHA20POLY1305_SHA512_Ed448 => 0x0006,
+            CipherSuite::MLS_256_DHKEMP384_AES256GCM_SHA384_P384 => 0x0007,
+            CipherSuite::Unknown(v) => v,
+        }
     }
 }
 
-/// [RFC9420 Sec.7.2](https://www.rfc-editor.org/rfc/rfc9420.html#section-7.2) CipherSuiteCapability is
-/// used in a leaf node in the tree to indicate an individual client's CipherSuite Capability.
-#[derive(Default, Debug, Copy, Clone, Eq, PartialEq, Hash)]
-pub struct CipherSuiteCapability(pub(crate) u16);
-
-impl TryFrom<CipherSuiteCapability> for CipherSuite {
-    type Error = Error;
-
-    fn try_from(c: CipherSuiteCapability) -> std::result::Result<Self, Self::Error> {
-        match c.0 {
-            0x0001 => Ok(CipherSuite::MLS_128_DHKEMX25519_AES128GCM_SHA256_Ed25519),
-            0x0002 => Ok(CipherSuite::MLS_128_DHKEMP256_AES128GCM_SHA256_P256),
-            0x0003 => Ok(CipherSuite::MLS_128_DHKEMX25519_CHACHA20POLY1305_SHA256_Ed25519),
-            0x0004 => Ok(CipherSuite::MLS_256_DHKEMX448_AES256GCM_SHA512_Ed448),
-            0x0005 => Ok(CipherSuite::MLS_256_DHKEMP521_AES256GCM_SHA512_P521),
-            0x0006 => Ok(CipherSuite::MLS_256_DHKEMX448_CHACHA20POLY1305_SHA512_Ed448),
-            0x0007 => Ok(CipherSuite::MLS_256_DHKEMP384_AES256GCM_SHA384_P384),
-            _ => Err(Error::InvalidCipherSuiteValue(c.0)),
-        }
+impl Display for CipherSuite {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{self:?}")
     }
 }
diff --git a/rmls/src/crypto/crypto_test.rs b/rmls/src/crypto/crypto_test.rs
@@ -227,18 +227,18 @@ fn test_crypto_basics_with_crypto_provider(
     crypto_provider: &impl CryptoProvider,
 ) -> Result<()> {
     for tc in tests {
-        let cipher_suite: CipherSuite = tc.cipher_suite.try_into()?;
+        let cipher_suite: CipherSuite = tc.cipher_suite.into();
         println!("test_crypto_basics {}", cipher_suite);
 
-        test_ref_hash(crypto_provider, cipher_suite, &tc.ref_hash)?;
+        if crypto_provider.supports(cipher_suite) {
+            test_ref_hash(crypto_provider, cipher_suite, &tc.ref_hash)?;
 
-        test_expand_with_label(crypto_provider, cipher_suite, &tc.expand_with_label)?;
+            test_expand_with_label(crypto_provider, cipher_suite, &tc.expand_with_label)?;
 
-        test_derive_secret(crypto_provider, cipher_suite, &tc.derive_secret)?;
+            test_derive_secret(crypto_provider, cipher_suite, &tc.derive_secret)?;
 
-        test_derive_tree_secret(crypto_provider, cipher_suite, &tc.derive_tree_secret)?;
+            test_derive_tree_secret(crypto_provider, cipher_suite, &tc.derive_tree_secret)?;
 
-        if crypto_provider.supports(cipher_suite) {
             test_sign_with_label(crypto_provider, cipher_suite, &tc.sign_with_label)?;
 
             test_encrypt_with_label(crypto_provider, cipher_suite, &tc.encrypt_with_label)?;

diff --git a/rmls/src/crypto/provider/mod.rs b/rmls/src/crypto/provider/mod.rs
@@ -169,18 +169,18 @@ pub trait CryptoProvider {
     fn rand(&self) -> &dyn Rand;
 
     /// Derive Hash trait object based on the given cipher suite
-    fn hash(&self, cipher_suite: CipherSuite) -> &dyn Hash;
+    fn hash(&self, cipher_suite: CipherSuite) -> Result<&dyn Hash>;
 
     /// Derive Hpke trait object based on the given cipher suite
-    fn hpke(&self, cipher_suite: CipherSuite) -> &dyn Hpke;
+    fn hpke(&self, cipher_suite: CipherSuite) -> Result<&dyn Hpke>;
 
     /// Derive Signature trait object based on the given cipher suite
-    fn signature(&self, cipher_suite: CipherSuite) -> &dyn Signature;
+    fn signature(&self, cipher_suite: CipherSuite) -> Result<&dyn Signature>;
 
     /// HMAC based sign based on the given cipher suite
-    fn sign_mac(&self, cipher_suite: CipherSuite, key: &[u8], message: &[u8]) -> Bytes {
+    fn sign_mac(&self, cipher_suite: CipherSuite, key: &[u8], message: &[u8]) -> Result<Bytes> {
         // All cipher suites use HMAC
-        self.hash(cipher_suite).mac(key, message)
+        Ok(self.hash(cipher_suite)?.mac(key, message))
     }
 
     /// HMAC based verify based on the given cipher suite
@@ -190,8 +190,12 @@ pub trait CryptoProvider {
         key: &[u8],
         message: &[u8],
         tag: &[u8],
-    ) -> bool {
-        tag == self.sign_mac(cipher_suite, key, message).as_ref()
+    ) -> Result<()> {
+        if tag == self.sign_mac(cipher_suite, key, message)?.as_ref() {
+            Ok(())
+        } else {
+            Err(Error::VerifyConfirmationTagFailed)
+        }
     }
 
     /// [RFC9420 Sec.5.2](https://www.rfc-editor.org/rfc/rfc9420.html#section-5.2) Hash-Based Identifiers
@@ -200,7 +204,7 @@ pub trait CryptoProvider {
         serialize_opaque_vec(label, &mut buf)?;
         serialize_opaque_vec(value, &mut buf)?;
         let input = buf.freeze();
-        let h = self.hash(cipher_suite);
+        let h = self.hash(cipher_suite)?;
         Ok(h.digest(&input))
     }
 
@@ -221,7 +225,7 @@ pub trait CryptoProvider {
         serialize_opaque_vec(&mls_label, &mut buf)?;
         serialize_opaque_vec(context, &mut buf)?;
         let info = buf.freeze();
-        self.hpke(cipher_suite).kdf_expand(secret, &info, length)
+        self.hpke(cipher_suite)?.kdf_expand(secret, &info, length)
     }
 
     /// Derive secret with label
@@ -231,7 +235,7 @@ pub trait CryptoProvider {
         secret: &[u8],
         label: &[u8],
     ) -> Result<Bytes> {
-        let length = self.hpke(cipher_suite).kdf_extract_size();
+        let length = self.hpke(cipher_suite)?.kdf_extract_size();
         self.expand_with_label(cipher_suite, secret, label, &[], length as u16)
     }
 
@@ -244,7 +248,7 @@ pub trait CryptoProvider {
         content: &[u8],
     ) -> Result<Bytes> {
         let sign_content = mls_prefix_label_data(label, content)?;
-        self.signature(cipher_suite).sign(sign_key, &sign_content)
+        self.signature(cipher_suite)?.sign(sign_key, &sign_content)
     }
 
     /// [RFC9420 Sec.5.1.2](https://www.rfc-editor.org/rfc/rfc9420.html#section-5.1.2) Verify message with label
@@ -257,7 +261,7 @@ pub trait CryptoProvider {
         sign_value: &[u8],
     ) -> Result<()> {
         let sign_content = mls_prefix_label_data(label, content)?;
-        self.signature(cipher_suite)
+        self.signature(cipher_suite)?
             .verify(verify_key, &sign_content, sign_value)
     }
 
@@ -353,9 +357,8 @@ pub trait CryptoProvider {
             CipherSuite::MLS_256_DHKEMX448_AES256GCM_SHA512_Ed448
             | CipherSuite::MLS_256_DHKEMP521_AES256GCM_SHA512_P521
             | CipherSuite::MLS_256_DHKEMX448_CHACHA20POLY1305_SHA512_Ed448
-            | CipherSuite::MLS_256_DHKEMP384_AES256GCM_SHA384_P384 => {
-                Err(Error::UnsupportedCipherSuite)
-            }
+            | CipherSuite::MLS_256_DHKEMP384_AES256GCM_SHA384_P384
+            | CipherSuite::Unknown(_) => Err(Error::UnsupportedCipherSuite),
         }
     }
 
@@ -440,9 +443,8 @@ pub trait CryptoProvider {
             CipherSuite::MLS_256_DHKEMX448_AES256GCM_SHA512_Ed448
             | CipherSuite::MLS_256_DHKEMP521_AES256GCM_SHA512_P521
             | CipherSuite::MLS_256_DHKEMX448_CHACHA20POLY1305_SHA512_Ed448
-            | CipherSuite::MLS_256_DHKEMP384_AES256GCM_SHA384_P384 => {
-                Err(Error::UnsupportedCipherSuite)
-            }
+            | CipherSuite::MLS_256_DHKEMP384_AES256GCM_SHA384_P384
+            | CipherSuite::Unknown(_) => Err(Error::UnsupportedCipherSuite),
         }
     }
 }

diff --git a/rmls/src/crypto/provider/provider_test.rs b/rmls/src/crypto/provider/provider_test.rs
@@ -6,9 +6,9 @@ fn test_signature_key_pair_with_crypto_provider(
     crypto_provider: &impl CryptoProvider,
 ) -> Result<()> {
     for c in 1..=7u16 {
-        let cipher_suite: CipherSuite = c.try_into()?;
+        let cipher_suite: CipherSuite = c.into();
         if crypto_provider.supports(cipher_suite) {
-            let signature = crypto_provider.signature(cipher_suite);
+            let signature = crypto_provider.signature(cipher_suite)?;
             let key_pair = signature.generate_key_pair()?;
             let out = signature.sign(key_pair.private_key(), PLAINTEXT)?;
             assert!(signature

diff --git a/rmls/src/crypto/provider/ring.rs b/rmls/src/crypto/provider/ring.rs
@@ -117,15 +117,30 @@ impl CryptoProvider for RingCryptoProvider {
         &self.rand
     }
 
-    fn hash(&self, cipher_suite: CipherSuite) -> &dyn Hash {
-        &CIPHER_SUITE_DESCRIPTIONS[cipher_suite as usize - 1].hash
+    fn hash(&self, cipher_suite: CipherSuite) -> Result<&dyn Hash> {
+        if self.supports(cipher_suite) {
+            let index: u16 = cipher_suite.into();
+            Ok(&CIPHER_SUITE_DESCRIPTIONS[index as usize - 1].hash)
+        } else {
+            Err(Error::UnsupportedCipherSuite)
+        }
     }
 
-    fn hpke(&self, cipher_suite: CipherSuite) -> &dyn Hpke {
-        &CIPHER_SUITE_DESCRIPTIONS[cipher_suite as usize - 1].hpke
+    fn hpke(&self, cipher_suite: CipherSuite) -> Result<&dyn Hpke> {
+        if self.supports(cipher_suite) {
+            let index: u16 = cipher_suite.into();
+            Ok(&CIPHER_SUITE_DESCRIPTIONS[index as usize - 1].hpke)
+        } else {
+            Err(Error::UnsupportedCipherSuite)
+        }
     }
 
-    fn signature(&self, cipher_suite: CipherSuite) -> &dyn Signature {
-        &CIPHER_SUITE_DESCRIPTIONS[cipher_suite as usize - 1].signature
+    fn signature(&self, cipher_suite: CipherSuite) -> Result<&dyn Signature> {
+        if self.supports(cipher_suite) {
+            let index: u16 = cipher_suite.into();
+            Ok(&CIPHER_SUITE_DESCRIPTIONS[index as usize - 1].signature)
+        } else {
+            Err(Error::UnsupportedCipherSuite)
+        }
     }
 }
diff --git a/rmls/src/crypto/provider/rust.rs b/rmls/src/crypto/provider/rust.rs
@@ -117,15 +117,30 @@ impl CryptoProvider for RustCryptoProvider {
         &self.rand
     }
 
-    fn hash(&self, cipher_suite: CipherSuite) -> &dyn Hash {
-        &CIPHER_SUITE_DESCRIPTIONS[cipher_suite as usize - 1].hash
+    fn hash(&self, cipher_suite: CipherSuite) -> Result<&dyn Hash> {
+        if self.supports(cipher_suite) {
+            let index: u16 = cipher_suite.into();
+            Ok(&CIPHER_SUITE_DESCRIPTIONS[index as usize - 1].hash)
+        } else {
+            Err(Error::UnsupportedCipherSuite)
+        }
     }
 
-    fn hpke(&self, cipher_suite: CipherSuite) -> &dyn Hpke {
-        &CIPHER_SUITE_DESCRIPTIONS[cipher_suite as usize - 1].hpke
+    fn hpke(&self, cipher_suite: CipherSuite) -> Result<&dyn Hpke> {
+        if self.supports(cipher_suite) {
+            let index: u16 = cipher_suite.into();
+            Ok(&CIPHER_SUITE_DESCRIPTIONS[index as usize - 1].hpke)
+        } else {
+            Err(Error::UnsupportedCipherSuite)
+        }
     }
 
-    fn signature(&self, cipher_suite: CipherSuite) -> &dyn Signature {
-        &CIPHER_SUITE_DESCRIPTIONS[cipher_suite as usize - 1].signature
+    fn signature(&self, cipher_suite: CipherSuite) -> Result<&dyn Signature> {
+        if self.supports(cipher_suite) {
+            let index: u16 = cipher_suite.into();
+            Ok(&CIPHER_SUITE_DESCRIPTIONS[index as usize - 1].signature)
+        } else {
+            Err(Error::UnsupportedCipherSuite)
+        }
     }
 }