Add some tests

src/ikm.rs

@@ -40,7 +40,7 @@ impl InputKeyMaterial {
 		Ok(res.try_into().unwrap())
 	}
 
-	fn from_bytes(b: [u8; IKM_STRUCT_SIZE]) -> Result<Self, Error> {
+	pub(crate) fn from_bytes(b: [u8; IKM_STRUCT_SIZE]) -> Result<Self, Error> {
 		Ok(Self {
 			id: u32::from_le_bytes(b[0..4].try_into().unwrap()),
 			scheme: u32::from_le_bytes(b[4..8].try_into().unwrap()).try_into()?,

src/kdf.rs

@@ -12,3 +12,42 @@ pub(crate) fn derive_key(ikm: &InputKeyMaterial, key_context: &[&str]) -> Vec<u8
 pub(crate) fn blake3_derive(context: &str, ikm: &[u8]) -> Vec<u8> {
 	blake3::derive_key(context, ikm).to_vec()
 }
+
+#[cfg(test)]
+mod tests {
+	use crate::ikm::InputKeyMaterial;
+
+	#[test]
+	fn derive_key() {
+		let ikm_raw = [
+			0x0a, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x7b, 0x85, 0x27, 0xef, 0xf2, 0xbd,
+			0x58, 0x9f, 0x6e, 0xb1, 0x7b, 0x71, 0xc3, 0x1e, 0xf6, 0xfd, 0x7f, 0x90, 0xdb, 0xc6,
+			0x43, 0xea, 0xe9, 0x9c, 0xa3, 0xb5, 0xee, 0xcc, 0xb6, 0xb6, 0x28, 0x6a, 0xbd, 0xe4,
+			0xd0, 0x65, 0x00, 0x00, 0x00, 0x00, 0x3d, 0x82, 0x6f, 0x8b, 0x00, 0x00, 0x00, 0x00,
+			0x00,
+		];
+		let ikm = InputKeyMaterial::from_bytes(ikm_raw).unwrap();
+
+		let ctx = ["some", "context"];
+		assert_eq!(
+			super::derive_key(&ikm, &ctx),
+			vec![
+				0xc1, 0xd2, 0xf0, 0xa7, 0x4d, 0xc5, 0x32, 0x6e, 0x89, 0x86, 0x85, 0xae, 0x3f, 0xdf,
+				0x16, 0x0b, 0xec, 0xe6, 0x63, 0x46, 0x41, 0x8a, 0x28, 0x2b, 0x04, 0xa1, 0x23, 0x20,
+				0x36, 0xe3, 0x2f, 0x0a
+			]
+		);
+	}
+
+	#[test]
+	fn blake3_derive() {
+		assert_eq!(
+			super::blake3_derive("this is a context", b"7b47db8f365e5b602fd956d35985e9e1"),
+			vec![
+				0xc4, 0xf4, 0x6c, 0xf2, 0x03, 0xd9, 0x2d, 0x7b, 0x72, 0xe8, 0xe7, 0x90, 0xa3, 0x62,
+				0x2a, 0xf4, 0x3c, 0x2a, 0xab, 0x27, 0xc6, 0xb1, 0x8b, 0x46, 0x9d, 0x40, 0x61, 0x56,
+				0x19, 0x76, 0x88, 0xc4
+			]
+		);
+	}
+}