Hi, I try to decrypt some string. Does this code looks good? I get error: CryptoKit.CryptoKitError error 3.
do { guard let encryptedData = Data(base64Encoded: cardNumber), let securityKeyData = Data(base64Encoded: securityKey), let ivData = Data(base64Encoded: iv), let privateKeyData = Data(base64Encoded: privateKey) else { throw NSError(domain: "invalid_input", code: 1, userInfo: [NSLocalizedDescriptionKey: "Invalid Base64 input."]) }
let privateKey = try P256.KeyAgreement.PrivateKey(derRepresentation: privateKeyData)
let publicKey = try P256.KeyAgreement.PublicKey(derRepresentation: securityKeyData)
let sharedSecret = try privateKey.sharedSecretFromKeyAgreement(with: publicKey)
let symmetricKey = sharedSecret.hkdfDerivedSymmetricKey(
using: SHA256.self,
salt: Data(),
sharedInfo: Data(),
outputByteCount: 32
)
let encryptedDataWithoutTag = encryptedData.dropLast(16)
let tagData = encryptedData.suffix(16)
let nonce = try AES.GCM.Nonce(data: ivData)
let sealedBox = try AES.GCM.SealedBox(nonce: nonce, ciphertext: encryptedDataWithoutTag, tag: tagData)
let decryptedData = try AES.GCM.open(sealedBox, using: symmetricKey)
resolve(decryptedCardNumber)
} catch {
print("Decryption failed with error: \(error.localizedDescription)")
reject("decryption_error", "Decryption failed with error: \(error.localizedDescription)", nil)
}