[bssl] Implement AEAD BoringSSL wrapper
AEAD will be used to encrypt the private key in the RKP HAL.
Bug: 302286887
Test: atest libbssl_avf_nostd.test
Change-Id: I734cf5ecd8b938f2c47f439d6f51594ccafb4ff2
diff --git a/libs/bssl/tests/aead_test.rs b/libs/bssl/tests/aead_test.rs
new file mode 100644
index 0000000..8ac3f12
--- /dev/null
+++ b/libs/bssl/tests/aead_test.rs
@@ -0,0 +1,148 @@
+// Copyright 2023, The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use bssl_avf::{Aead, AeadCtx, ApiName, CipherError, Error, ReasonCode, Result};
+
+/// The following vectors are generated randomly with:
+/// `hexdump -vn32 -e'32/1 "0x%02x, " 1 "\n"' /dev/urandom`
+const KEY1: [u8; 32] = [
+ 0xdb, 0x16, 0xcc, 0xbf, 0xf0, 0xc4, 0xbc, 0x93, 0xc3, 0x5f, 0x11, 0xc5, 0xfa, 0xae, 0x03, 0x6c,
+ 0x75, 0x40, 0x1f, 0x60, 0xb6, 0x3e, 0xb9, 0x2a, 0x6c, 0x84, 0x06, 0x4b, 0x36, 0x7f, 0xed, 0xdb,
+];
+const KEY2: [u8; 32] = [
+ 0xaa, 0x57, 0x7a, 0x1a, 0x8b, 0xa2, 0x59, 0x3b, 0xad, 0x5f, 0x4d, 0x29, 0xe1, 0x0c, 0xaa, 0x85,
+ 0xde, 0xf9, 0xad, 0xad, 0x8c, 0x11, 0x0c, 0x2e, 0x13, 0x43, 0xd7, 0xdf, 0x2a, 0x43, 0xb9, 0xdd,
+];
+/// The following vectors are generated randomly with:
+/// Generated with `hexdump -vn12 -e'12/1 "0x%02x, " 1 "\n"' /dev/urandom`
+const AES_256_GCM_NONCE1: [u8; 12] =
+ [0x56, 0x96, 0x73, 0xe1, 0xc6, 0x3d, 0xca, 0x9a, 0x2f, 0xad, 0x3b, 0xeb];
+const AES_256_GCM_NONCE2: [u8; 12] =
+ [0xa0, 0x27, 0xea, 0x3a, 0x29, 0xfa, 0x8a, 0x49, 0x35, 0x07, 0x32, 0xec];
+const MESSAGE: &[u8] = b"aead_aes_256_gcm test message";
+
+#[test]
+fn aes_256_gcm_encrypts_and_decrypts_successfully() -> Result<()> {
+ let ciphertext = aes_256_gcm_encrypt(MESSAGE)?;
+ let tag_len = None;
+
+ let ad = &[];
+ let aead_ctx = AeadCtx::new(Aead::aes_256_gcm(), &KEY1, tag_len)?;
+ let mut out = vec![0u8; ciphertext.len()];
+
+ let plaintext = aead_ctx.open(&ciphertext, &AES_256_GCM_NONCE1, ad, &mut out)?;
+
+ assert_eq!(MESSAGE, plaintext);
+ Ok(())
+}
+
+#[test]
+fn aes_256_gcm_fails_to_encrypt_with_invalid_nonce() -> Result<()> {
+ let tag_len = None;
+ let aead_ctx = AeadCtx::new(Aead::aes_256_gcm(), &KEY1, tag_len)?;
+ let nonce = &[];
+ let ad = &[];
+ let mut out = vec![0u8; MESSAGE.len() + aead_ctx.aead().max_overhead()];
+
+ let err = aead_ctx.seal(MESSAGE, nonce, ad, &mut out).unwrap_err();
+
+ let expected_err = Error::CallFailed(
+ ApiName::EVP_AEAD_CTX_seal,
+ ReasonCode::Cipher(CipherError::InvalidNonceSize),
+ );
+ assert_eq!(expected_err, err);
+ Ok(())
+}
+
+#[test]
+fn aes_256_gcm_fails_to_decrypt_with_wrong_key() -> Result<()> {
+ let ciphertext = aes_256_gcm_encrypt(MESSAGE)?;
+ let tag_len = None;
+
+ let ad = &[];
+ let aead_ctx2 = AeadCtx::new(Aead::aes_256_gcm(), &KEY2, tag_len)?;
+ let mut plaintext = vec![0u8; ciphertext.len()];
+
+ let err = aead_ctx2.open(&ciphertext, &AES_256_GCM_NONCE1, ad, &mut plaintext).unwrap_err();
+
+ let expected_err =
+ Error::CallFailed(ApiName::EVP_AEAD_CTX_open, ReasonCode::Cipher(CipherError::BadDecrypt));
+ assert_eq!(expected_err, err);
+ Ok(())
+}
+
+#[test]
+fn aes_256_gcm_fails_to_decrypt_with_different_ad() -> Result<()> {
+ let ciphertext = aes_256_gcm_encrypt(MESSAGE)?;
+ let tag_len = None;
+
+ let ad2 = &[1];
+ let aead_ctx = AeadCtx::new(Aead::aes_256_gcm(), &KEY1, tag_len)?;
+ let mut plaintext = vec![0u8; ciphertext.len()];
+
+ let err = aead_ctx.open(&ciphertext, &AES_256_GCM_NONCE1, ad2, &mut plaintext).unwrap_err();
+
+ let expected_err =
+ Error::CallFailed(ApiName::EVP_AEAD_CTX_open, ReasonCode::Cipher(CipherError::BadDecrypt));
+ assert_eq!(expected_err, err);
+ Ok(())
+}
+
+#[test]
+fn aes_256_gcm_fails_to_decrypt_with_different_nonce() -> Result<()> {
+ let ciphertext = aes_256_gcm_encrypt(MESSAGE)?;
+ let tag_len = None;
+
+ let ad = &[];
+ let aead_ctx = AeadCtx::new(Aead::aes_256_gcm(), &KEY1, tag_len)?;
+ let mut plaintext = vec![0u8; ciphertext.len()];
+
+ let err = aead_ctx.open(&ciphertext, &AES_256_GCM_NONCE2, ad, &mut plaintext).unwrap_err();
+
+ let expected_err =
+ Error::CallFailed(ApiName::EVP_AEAD_CTX_open, ReasonCode::Cipher(CipherError::BadDecrypt));
+ assert_eq!(expected_err, err);
+ Ok(())
+}
+
+#[test]
+fn aes_256_gcm_fails_to_decrypt_corrupted_ciphertext() -> Result<()> {
+ let mut ciphertext = aes_256_gcm_encrypt(MESSAGE)?;
+ ciphertext[1] = !ciphertext[1];
+ let tag_len = None;
+
+ let ad = &[];
+ let aead_ctx = AeadCtx::new(Aead::aes_256_gcm(), &KEY1, tag_len)?;
+ let mut plaintext = vec![0u8; ciphertext.len()];
+
+ let err = aead_ctx.open(&ciphertext, &AES_256_GCM_NONCE1, ad, &mut plaintext).unwrap_err();
+
+ let expected_err =
+ Error::CallFailed(ApiName::EVP_AEAD_CTX_open, ReasonCode::Cipher(CipherError::BadDecrypt));
+ assert_eq!(expected_err, err);
+ Ok(())
+}
+
+fn aes_256_gcm_encrypt(message: &[u8]) -> Result<Vec<u8>> {
+ let tag_len = None;
+ let aead_ctx = AeadCtx::new(Aead::aes_256_gcm(), &KEY1, tag_len)?;
+ let mut out = vec![0u8; message.len() + aead_ctx.aead().max_overhead()];
+
+ assert_eq!(aead_ctx.aead().nonce_length(), AES_256_GCM_NONCE1.len());
+ let ad = &[];
+
+ let ciphertext = aead_ctx.seal(message, &AES_256_GCM_NONCE1, ad, &mut out)?;
+ assert_ne!(message, ciphertext);
+ Ok(ciphertext.to_vec())
+}