Add the key length to the key context

src/coffio.rs

@@ -98,7 +98,7 @@ mod tests {
 	use super::*;
 	use crate::{DataContext, KeyContext};
 
-	const TEST_CIPHERTEXT: &str = "AQAAAA:W-nzcGkPU6eWj_JjjqLpQk6WSe_CIUPF:we_HR8yD3XnQ9aaJlZFvqPitnDlQHexw4QPaYaOTzpHSWNW86QQrLRRZOg:NgAAAAAAAAA";
+	const TEST_CIPHERTEXT: &str = "AQAAAA:qpVDbGvu0wl2tQgfF5jngCWCoCq5d9gj:eTkOSKz9YyvJE8PyT1lAFn4hyeK_0l6tWU4yyHA-7WRCJ9G-HWNpqoKBxg:NgAAAAAAAAA";
 	const TEST_DATA: &[u8] = b"Lorem ipsum dolor sit amet.";
 	const TEST_KEY_CTX: &[&str] = &["db_name", "table_name", "column_name"];
 	const TEST_DATA_CTX: &[&str] = &["018db876-3d9d-79af-9460-55d17da991d8"];
@@ -268,12 +268,12 @@ mod tests {
 	fn decrypt_invalid_ciphertext() {
 		let tests = &[
 			("", "empty data"),
-			("AQAATA:W-nzcGkPU6eWj_JjjqLpQk6WSe_CIUPF:we_HR8yD3XnQ9aaJlZFvqPitnDlQHexw4QPaYaOTzpHSWNW86QQrLRRZOg:NgAAAAAAAAA", "unknown ikm id"),
+			("AQAATA:qpVDbGvu0wl2tQgfF5jngCWCoCq5d9gj:eTkOSKz9YyvJE8PyT1lAFn4hyeK_0l6tWU4yyHA-7WRCJ9G-HWNpqoKBxg:NgAAAAAAAAA", "unknown ikm id"),
-			("AQAAAA:MTIzNDU2Nzg5MDEyMzQ1Njc4OTAxMjM0:we_HR8yD3XnQ9aaJlZFvqPitnDlQHexw4QPaYaOTzpHSWNW86QQrLRRZOg:NgAAAAAAAAA", "invalid nonce"),
+			("AQAAAA:8pVDbGvu0wl2tQgfF5jngCWCoCq5d9gj:eTkOSKz9YyvJE8PyT1lAFn4hyeK_0l6tWU4yyHA-7WRCJ9G-HWNpqoKBxg:NgAAAAAAAAA", "invalid nonce"),
-			("AQAAAA:W-nzcGkPU6eWj_JjjqLpQk6WSe_CIUPF:8e_HR8yD3XnQ9aaJlZFvqPitnDlQHexw4QPaYaOTzpHSWNW86QQrLRRZOg:NgAAAAAAAAA", "invalid ciphertext"),
+			("AQAAAA:qpVDbGvu0wl2tQgfF5jngCWCoCq5d9gj:8TkOSKz9YyvJE8PyT1lAFn4hyeK_0l6tWU4yyHA-7WRCJ9G-HWNpqoKBxg:NgAAAAAAAAA", "invalid ciphertext"),
-			("AQAAAA:W-nzcGkPU6eWj_JjjqLpQk6WSe_CIUPF:we_HR8yD3XnQ9aaJlZFvqPitnDlQHexw4QPaYaOTzpHSWNW86QQrLRRZOg:NaAAAAAAAAA", "invalid time period"),
+			("AQAAAA:qpVDbGvu0wl2tQgfF5jngCWCoCq5d9gj:eTkOSKz9YyvJE8PyT1lAFn4hyeK_0l6tWU4yyHA-7WRCJ9G-HWNpqoKBxg:NaAAAAAAAAA", "invalid time period"),
-			("AQAAAA:W-nzcGkPU6eWj_JjjqLpQk6WSe_CIUPF:we_HR8yD3XnQ9aaJlZFvqPitnDlQHexw4QPaYaOTzpHSWNW86QQrLRRZOg:", "empty time period"),
+			("AQAAAA:qpVDbGvu0wl2tQgfF5jngCWCoCq5d9gj:eTkOSKz9YyvJE8PyT1lAFn4hyeK_0l6tWU4yyHA-7WRCJ9G-HWNpqoKBxg:", "empty time period"),
-			("AQAAAA:W-nzcGkPU6eWj_JjjqLpQk6WSe_CIUPF:we_HR8yD3XnQ9aaJlZFvqPitnDlQHexw4QPaYaOTzpHSWNW86QQrLRRZOg", "missing time period"),
+			("AQAAAA:qpVDbGvu0wl2tQgfF5jngCWCoCq5d9gj:eTkOSKz9YyvJE8PyT1lAFn4hyeK_0l6tWU4yyHA-7WRCJ9G-HWNpqoKBxg", "missing time period"),
 		];
 
 		let lst = get_ikm_lst_chacha20poly1305_blake3();

src/kdf.rs

@@ -9,7 +9,8 @@ pub(crate) fn derive_key(
 	ctx: &KeyContext,
 	time_period: Option<u64>,
 ) -> Vec<u8> {
-	let elems = ctx.get_ctx_elems(time_period);
+	let mut elems = ctx.get_ctx_elems(time_period);
+	elems.push(ikm.scheme.get_key_len().to_le_bytes().to_vec());
 	let key_context = canonicalize(&elems);
 	let kdf = ikm.scheme.get_kdf();
 	kdf(&key_context, &ikm.content)
@@ -36,9 +37,9 @@ mod tests {
 		assert_eq!(
 			super::derive_key(&ikm, &ctx, None),
 			vec![
-				0xc1, 0xd2, 0xf0, 0xa7, 0x4d, 0xc5, 0x32, 0x6e, 0x89, 0x86, 0x85, 0xae, 0x3f, 0xdf,
+				0xf9, 0x90, 0x22, 0x8, 0x9a, 0x63, 0x2, 0xc9, 0xd0, 0x7c, 0x71, 0x56, 0xa4, 0xc3,
-				0x16, 0x0b, 0xec, 0xe6, 0x63, 0x46, 0x41, 0x8a, 0x28, 0x2b, 0x04, 0xa1, 0x23, 0x20,
+				0x8c, 0x4b, 0x1d, 0xe8, 0x56, 0xf2, 0xc3, 0xf6, 0xba, 0xc3, 0x4b, 0x8d, 0x85, 0x29,
-				0x36, 0xe3, 0x2f, 0x0a
+				0x4b, 0x5, 0x13, 0xc3
 			]
 		);
 	}
@@ -51,9 +52,9 @@ mod tests {
 		assert_eq!(
 			super::derive_key(&ikm, &ctx, Some(0)),
 			vec![
-				0xdc, 0x6c, 0x4b, 0xed, 0xef, 0x31, 0x2a, 0x83, 0x40, 0xc0, 0xee, 0xf4, 0xd7, 0xe5,
+				0xfe, 0x70, 0x65, 0x84, 0x79, 0x9a, 0xc0, 0xf1, 0x50, 0xb5, 0x72, 0x73, 0x16, 0xf4,
-				0xec, 0x2e, 0xcf, 0xda, 0x64, 0x0a, 0xb8, 0xb6, 0x89, 0xe4, 0x3c, 0x6e, 0xc2, 0x53,
+				0x5b, 0x49, 0xb4, 0x46, 0xfa, 0x58, 0xa6, 0xb9, 0xf0, 0xc7, 0xec, 0x49, 0x87, 0x7e,
-				0x0e, 0xaa, 0x38, 0x12
+				0x46, 0xd0, 0x9, 0xe8
 			]
 		);
 	}
@@ -66,9 +67,9 @@ mod tests {
 		assert_eq!(
 			super::derive_key(&ikm, &ctx, Some(42)),
 			vec![
-				0xc7, 0xfb, 0x96, 0x6a, 0x15, 0xde, 0x5f, 0xfc, 0x66, 0xa6, 0xac, 0xda, 0x6b, 0x8e,
+				0x5c, 0x9b, 0x1c, 0xfa, 0x21, 0xac, 0xdb, 0x37, 0x4d, 0xee, 0x60, 0xf7, 0x6, 0x18,
-				0xa3, 0x66, 0xd8, 0x70, 0x5b, 0x2f, 0xf9, 0x7f, 0xfb, 0x47, 0xb1, 0xa9, 0x93, 0xfc,
+				0x85, 0xb5, 0x95, 0x2a, 0x6c, 0xd3, 0x43, 0x9, 0xcb, 0x1b, 0x7f, 0x9d, 0xdf, 0x58,
-				0xf5, 0x0b, 0x6d, 0x3c
+				0xf9, 0x3e, 0x6e, 0x14
 			]
 		);
 	}

src/scheme.rs

@@ -88,6 +88,15 @@ impl Scheme {
 		}
 	}
 
+	pub(crate) fn get_key_len(&self) -> usize {
+		match self {
+			#[cfg(feature = "chacha")]
+			Scheme::XChaCha20Poly1305WithBlake3 => xchacha20poly1305::KEY_SIZE,
+			#[cfg(feature = "aes")]
+			Scheme::Aes128GcmWithSha256 => aes::AES128_KEY_SIZE,
+		}
+	}
+
 	pub(crate) fn get_decryption(&self) -> Box<DecryptionFunction> {
 		match self {
 			#[cfg(feature = "chacha")]

src/scheme/aes.rs

@@ -3,6 +3,7 @@ use crate::error::{Error, Result};
 use aes_gcm::aead::{Aead, KeyInit, Payload};
 use aes_gcm::{Aes128Gcm, Key, Nonce};
 
+pub(crate) const AES128_KEY_SIZE: usize = 128;
 // 96 bits (12 bytes)
 // Reason: NIST Special Publication 800-38D
 // https://doi.org/10.6028/NIST.SP.800-38D

src/scheme/xchacha20poly1305.rs

@@ -3,6 +3,7 @@ use crate::error::{Error, Result};
 use chacha20poly1305::aead::{Aead, KeyInit, Payload};
 use chacha20poly1305::{Key, XChaCha20Poly1305, XNonce};
 
+pub(crate) const KEY_SIZE: usize = 256;
 // X-variant: the nonce's size is 192 bits (24 bytes)
 const NONCE_SIZE: usize = 24;