Method initKey

flow/BlobCipher.cpp:67–94

}

void BlobCipherKey::initKey(const EncryptCipherDomainId& domainId,
                            const uint8_t* baseCiph,
                            int baseCiphLen,
                            const EncryptCipherBaseKeyId& baseCiphId,
                            const EncryptCipherRandomSalt& salt) {
	// Set the base encryption key properties
	baseCipher = std::make_unique<uint8_t[]>(AES_256_KEY_LENGTH);
	memset(baseCipher.get(), 0, AES_256_KEY_LENGTH);
	memcpy(baseCipher.get(), baseCiph, std::min<int>(baseCiphLen, AES_256_KEY_LENGTH));
	baseCipherLen = baseCiphLen;
	baseCipherId = baseCiphId;
	// Set the encryption domain for the base encryption key
	encryptDomainId = domainId;
	randomSalt = salt;
	// derive the encryption key
	cipher = std::make_unique<uint8_t[]>(AES_256_KEY_LENGTH);
	memset(cipher.get(), 0, AES_256_KEY_LENGTH);
	applyHmacSha256Derivation();
	// update the key creation time
	creationTime = now();

	TraceEvent("BlobCipherKey")
	    .detail("DomainId", domainId)
	    .detail("BaseCipherId", baseCipherId)
	    .detail("BaseCipherLen", baseCipherLen)
	    .detail("RandomSalt", randomSalt)
	    .detail("CreationTime", creationTime);
}

void BlobCipherKey::applyHmacSha256Derivation() {
	Arena arena;