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Plain text encryption using RSA Public Key in Dart

I am new at flutter development, I am trying to use send ENCRYPTED data on server using a public key in flutter .
I have .cer certificate and i have RSA public key in flutter. Now in Java I'm using for Encrypt the Plain Text using RSA public key i have done this
successfully . How can i do this in flutter ?
public String encrypt(String string, final X509Certificate x509Certificate) throws NoSuchAlgorithmException, NoSuchPaddingException, IOException, IllegalBlockSizeException, BadPaddingException, InvalidKeyException, InvalidAlgorithmParameterException {
Cipher a = Cipher.getInstance("RSA");
final KeyGenerator instance;
(instance = KeyGenerator.getInstance("AES")).init(256);
byte[] b = instance.generateKey().getEncoded();
System.out.println("print encoded key"+b);
printUnsignedBytes(b);
aesKey = b;
new SecretKeySpec(b, "AES");
a.init(1, x509Certificate.getPublicKey());
final ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
final CipherOutputStream cipherOutputStream;
(cipherOutputStream = new CipherOutputStream(byteArrayOutputStream, a)).write(b);
cipherOutputStream.close();
byte[] c = byteArrayOutputStream.toByteArray();
final byte[] array = new byte[16];
new SecureRandom().nextBytes(array);
final Cipher instance2;
(instance2 = Cipher.getInstance("AES/CBC/NOPADDING")).init(1, new SecretKeySpec(b, "AES"),
new IvParameterSpec(array));
byte[] bytes = s.getBytes();
int remainder = 16 - (bytes.length % 16);
byte[] remainderFilledWithSpaces = new byte[remainder];
for (int i = 0; i < remainderFilledWithSpaces.length; i++) {
remainderFilledWithSpaces[i] = " ".getBytes()[0];
}
int totalLength = bytes.length + remainder;
ByteBuffer bb = ByteBuffer.allocate(totalLength);
bb.put(bytes);
bb.put(remainderFilledWithSpaces);
bb.position(0);
byte[] blockToEncrypt = new byte[16];
ByteBuffer encrypted = ByteBuffer.allocate(totalLength);
while (bb.hasRemaining()) {
bb.get(blockToEncrypt);
byte[] update = instance2.update(blockToEncrypt);
encrypted.put(update);
}
instance2.doFinal();
final ByteArrayOutputStream byteArrayOutputStream2 = new ByteArrayOutputStream();
final byte[] array2;
(array2 = new byte[4])[0] = 0;
array2[1] = 1;
array2[3] = (array2[2] = 0);
byteArrayOutputStream2.write(array2, 0, 4);
array2[0] = 16;
array2[1] = 0;
array2[3] = (array2[2] = 0);
byteArrayOutputStream2.write(array2, 0, 4);
byteArrayOutputStream2.write(c, 0, 256);
byteArrayOutputStream2.write(array, 0, 16);
byteArrayOutputStream2.write(encrypted.array());
return s = new String(Base64.getMimeEncoder().encode(byteArrayOutputStream2.toByteArray()));
}
Now , I want this same solution in Dart .Please help,thanks a lot.

Aes decrypt file java with base64 data encoding

I referred this and trying to do file decryption with base64 decoding
My requirement is to encode data with base64 during encryption and decode data with base64 during decryption.
But im facing below error:
javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipher
at java.base/com.sun.crypto.provider.CipherCore.doFinal(Unknown Source)
at java.base/com.sun.crypto.provider.CipherCore.doFinal(Unknown Source)
at java.base/com.sun.crypto.provider.AESCipher.engineDoFinal(Unknown Source)
at java.base/javax.crypto.Cipher.doFinal(Unknown Source)
at aes.DecryptNew.decryptNew(DecryptNew.java:124)
at aes.DecryptNew.main(DecryptNew.java:32)
Also im confused on how to perform decryption in chunks.
Please suggest me issues in this code.
import javax.crypto.Cipher;
import javax.crypto.CipherOutputStream;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.security.*;
import java.util.Arrays;
import java.util.Base64;
public class DecryptNew {
public static void main(String[] args) {
String plaintextFilename = "D:\\\\plaintext.txt";
String ciphertextFilename = "D:\\\\plaintext.txt.crypt";
String decryptedtextFilename = "D:\\\\plaintextDecrypted.txt";
String password = "testpass";
writeToFile();
String ciphertext = encryptfile(plaintextFilename, password);
System.out.println("ciphertext: " + ciphertext);
decryptNew(ciphertextFilename, password, decryptedtextFilename);
}
static void writeToFile() {
BufferedWriter writer = null;
try
{
writer = new BufferedWriter( new FileWriter("D:\\\\plaintext.txt"));
byte[] data = Base64.getEncoder().encode("hello\r\nhello".getBytes(StandardCharsets.UTF_8));
writer.write(new String(data));
}
catch ( IOException e)
{
}
finally
{
try
{
if ( writer != null)
writer.close( );
}
catch ( IOException e)
{
}
}
}
public static String encryptfile(String path, String password) {
try {
FileInputStream fis = new FileInputStream(path);
FileOutputStream fos = new FileOutputStream(path.concat(".crypt"));
final byte[] pass = Base64.getEncoder().encode(password.getBytes());
final byte[] salt = (new SecureRandom()).generateSeed(8);
fos.write(Base64.getEncoder().encode("Salted__".getBytes()));
fos.write(salt);
final byte[] passAndSalt = concatenateByteArrays(pass, salt);
byte[] hash = new byte[0];
byte[] keyAndIv = new byte[0];
for (int i = 0; i < 3 && keyAndIv.length < 48; i++) {
final byte[] hashData = concatenateByteArrays(hash, passAndSalt);
final MessageDigest md = MessageDigest.getInstance("SHA-1");
hash = md.digest(hashData);
keyAndIv = concatenateByteArrays(keyAndIv, hash);
}
final byte[] keyValue = Arrays.copyOfRange(keyAndIv, 0, 32);
final byte[] iv = Arrays.copyOfRange(keyAndIv, 32, 48);
final SecretKeySpec key = new SecretKeySpec(keyValue, "AES");
final Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, key, new IvParameterSpec(iv));
CipherOutputStream cos = new CipherOutputStream(fos, cipher);
int b;
byte[] d = new byte[8];
while ((b = fis.read(d)) != -1) {
cos.write(d, 0, b);
}
cos.flush();
cos.close();
fis.close();
System.out.println("encrypt done " + path);
} catch (IOException | NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | InvalidAlgorithmParameterException e) {
e.printStackTrace();
}
return path;
}
static void decryptNew(String path,String password, String outPath) {
byte[] SALTED_MAGIC = Base64.getEncoder().encode("Salted__".getBytes());
try{
FileInputStream fis = new FileInputStream(path);
FileOutputStream fos = new FileOutputStream(outPath);
final byte[] pass = password.getBytes(StandardCharsets.US_ASCII);
final byte[] inBytes = Files.readAllBytes(Paths.get(path));
final byte[] shouldBeMagic = Arrays.copyOfRange(inBytes, 0, SALTED_MAGIC.length);
if (!Arrays.equals(shouldBeMagic, SALTED_MAGIC)) {
throw new IllegalArgumentException("Initial bytes from input do not match OpenSSL SALTED_MAGIC salt value.");
}
final byte[] salt = Arrays.copyOfRange(inBytes, SALTED_MAGIC.length, SALTED_MAGIC.length + 8);
final byte[] passAndSalt = concatenateByteArrays(pass, salt);
byte[] hash = new byte[0];
byte[] keyAndIv = new byte[0];
for (int i = 0; i < 3 && keyAndIv.length < 48; i++) {
final byte[] hashData = concatenateByteArrays(hash, passAndSalt);
MessageDigest md = null;
md = MessageDigest.getInstance("SHA-1");
hash = md.digest(hashData);
keyAndIv = concatenateByteArrays(keyAndIv, hash);
}
final byte[] keyValue = Arrays.copyOfRange(keyAndIv, 0, 32);
final SecretKeySpec key = new SecretKeySpec(keyValue, "AES");
final byte[] iv = Arrays.copyOfRange(keyAndIv, 32, 48);
final Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(iv));
final byte[] clear = cipher.doFinal(inBytes, 16, inBytes.length - 16);
String contentDecoded = new String(Base64.getDecoder().decode(clear));
fos.write(contentDecoded.getBytes());
fos.close();
System.out.println("Decrypt is completed");
}catch(Exception e){
e.printStackTrace();
}
}
public static byte[] concatenateByteArrays(byte[] a, byte[] b) {
return ByteBuffer
.allocate(a.length + b.length)
.put(a).put(b)
.array();
}
}

As mentioned in my first comment: Encryption and decryption use different encodings for the password (Base64 in encryption, ASCII in decryption).
In addition the prefix is Base64 encoded in both encryption and decryption, so prefix plus salt are larger than one block (16 bytes), and therefore the subsequent length determination of the ciphertext during decryption fails, as it is assumed that the ciphertext starts with the 2nd block.
Both issues can be solved if the same encoding is used for the password in encryption and decryption (e.g. ASCII) and the prefix is ASCII encoded, e.g. for encryption:
...
byte[] pass = password.getBytes(StandardCharsets.US_ASCII);
byte[] SALTED_MAGIC = "Salted__".getBytes(StandardCharsets.US_ASCII);
byte[] salt = (new SecureRandom()).generateSeed(8);
fos.write(SALTED_MAGIC);
fos.write(salt);
...
and for decryption:
...
byte[] pass = password.getBytes(StandardCharsets.US_ASCII);
byte[] SALTED_MAGIC = "Salted__".getBytes(StandardCharsets.US_ASCII);
byte[] prefix = fis.readNBytes(8);
byte[] salt = fis.readNBytes(8);
...
However the current encryption method does not Base64 encode (only the prefix is Base64 encoded which is rather counterproductive, s. above).
Even a Base64 encoded plaintext does not change this, as the ciphertext itself is not Base64 encoded.
Considering your statement My requirement is to encode data with base64 during encryption and decode data with base64 during decryption and the OpenSSL format used, I assume that you want to decrypt a ciphertext that has been encrypted with the -base64 option, analogous to OpenSSL, i.e. with
openssl enc -aes-256-cbc -base64 -pass pass:testpass -p -in sample.txt -out sample.crypt
Here, prefix, salt and ciphertext are concatenated on byte level and the result is then Base64 encoded. To achieve this, your implementation posted in the question could be changed as follows:
static void decrypt(String path, String password, String outPath) {
try (FileInputStream fis = new FileInputStream(path);
Base64InputStream bis = new Base64InputStream(fis, false, 64, "\r\n".getBytes(StandardCharsets.US_ASCII))) { // from Apache Commons Codec
// Read prefix and salt
byte[] SALTED_MAGIC = "Salted__".getBytes(StandardCharsets.US_ASCII);
byte[] prefix = bis.readNBytes(8);
if (!Arrays.equals(prefix, SALTED_MAGIC)) {
throw new IllegalArgumentException("Initial bytes from input do not match OpenSSL SALTED_MAGIC salt value.");
}
byte[] salt = bis.readNBytes(8);
// Derive key and IV
byte[] pass = password.getBytes(StandardCharsets.US_ASCII);
byte[] passAndSalt = concatenateByteArrays(pass, salt);
byte[] hash = new byte[0];
byte[] keyAndIv = new byte[0];
for (int i = 0; i < 3 && keyAndIv.length < 48; i++) {
byte[] hashData = concatenateByteArrays(hash, passAndSalt);
MessageDigest md = null;
md = MessageDigest.getInstance("SHA-1"); // Use digest from encryption
hash = md.digest(hashData);
keyAndIv = concatenateByteArrays(keyAndIv, hash);
}
byte[] keyValue = Arrays.copyOfRange(keyAndIv, 0, 32);
SecretKeySpec key = new SecretKeySpec(keyValue, "AES");
byte[] iv = Arrays.copyOfRange(keyAndIv, 32, 48);
// Decrypt
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(iv));
try (CipherInputStream cis = new CipherInputStream(bis, cipher);
FileOutputStream fos = new FileOutputStream(outPath)) {
int length;
byte[] buffer = new byte[1024];
while ((length = cis.read(buffer)) != -1) {
fos.write(buffer, 0, length);
}
}
System.out.println("Decrypt is completed");
} catch (Exception e) {
e.printStackTrace();
}
}
As I already mentioned in the comments to the linked question, the processing in chunks can easily be implemented with the class CipherInputStream. The Base64 decoding can be achieved with the class Base64InputStream of the Apache Commons Codec, as also addressed by Michael Fehr. This is a convenient way to perform Base64 decoding and decryption together. If the data does not need to be Base64 decoded (e.g. if the -base64 option was not used during encryption) the Base64InputStream class can simply be omitted.
As previously stated in the comments, small files do not need to be processed in chunks. This is only necessary when the files become large relative to the memory. However, since your encryption method processes the data in chunks, it is consistent that the decryption does the same.
Note that the encryption posted in the question is not compatible with the result of the above OpenSSL statement, i.e. the encryption would have to be adapted if necessary (analogous to the decryption posted above).
Edit: The encryptfile() method posted in the question creates a file containing the Base64 encoded prefix, the raw salt and the raw ciphertext. For key derivation the Base64 encoded password is applied. The method is used to encrypt a Base64 encoded plaintext. The following method is the counterpart of encryptfile() and allows the decryption and Base64 decoding of the plaintext:
static void decryptfile(String path, String password, String outPath) {
try (FileInputStream fis = new FileInputStream(path)) {
// Read prefix and salt
byte[] SALTED_MAGIC = Base64.getEncoder().encode("Salted__".getBytes());
byte[] prefix = new byte[SALTED_MAGIC.length];
fis.readNBytes(prefix, 0, prefix.length);
if (!Arrays.equals(prefix, SALTED_MAGIC)) {
throw new IllegalArgumentException("Initial bytes from input do not match OpenSSL SALTED_MAGIC salt value.");
}
byte[] salt = new byte[8];
fis.readNBytes(salt, 0, salt.length);
// Derive key and IV
final byte[] pass = Base64.getEncoder().encode(password.getBytes());
byte[] passAndSalt = concatenateByteArrays(pass, salt);
byte[] hash = new byte[0];
byte[] keyAndIv = new byte[0];
for (int i = 0; i < 3 && keyAndIv.length < 48; i++) {
byte[] hashData = concatenateByteArrays(hash, passAndSalt);
MessageDigest md = null;
md = MessageDigest.getInstance("SHA-1"); // Use digest from encryption
hash = md.digest(hashData);
keyAndIv = concatenateByteArrays(keyAndIv, hash);
}
byte[] keyValue = Arrays.copyOfRange(keyAndIv, 0, 32);
SecretKeySpec key = new SecretKeySpec(keyValue, "AES");
byte[] iv = Arrays.copyOfRange(keyAndIv, 32, 48);
// Decrypt
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(iv));
try (CipherInputStream cis = new CipherInputStream(fis, cipher);
Base64InputStream bis = new Base64InputStream(cis, false, -1, null); // from Apache Commons Codec
FileOutputStream fos = new FileOutputStream(outPath)) {
int length;
byte[] buffer = new byte[1024];
while ((length = bis.read(buffer)) != -1) {
fos.write(buffer, 0, length);
}
}
System.out.println("Decrypt is completed");
} catch (Exception e) {
e.printStackTrace();
}
}
The decryptfile()-method writes the Base64 decoded plaintext to the file in outPath. To get the Base64 encoded plaintext simply remove the Base64InputStream instance from the stream hierarchy.
As already explained in the comment, this method is incompatible to OpenSSL, i.e. it can't decrypt ciphertexts generated with the OpenSSL statement posted above (with or without -base64 option). To decrypt a ciphertext generated with OpenSSL with -base64 option use the decrypt() method.

Java Cipher Decryption on large files

I am trying to decrypt files by Java and below codes work. However it will have OutOfMemory exception when decrypting large files. I tried to change to cipher.update but the program will freeze without any responding.
How can I change this from doFinal to update?
public File decryptDataFile(File inputFile, File outputFile, File keyFile, String correlationId) {
try {
Security.addProvider(new BouncyCastleProvider());
String key = new String(Files.readAllBytes(keyFile.toPath())).trim();
byte[] byteInput = this.getFileInBytes(inputFile);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding", "BC");
byte[] salt = new byte[8];
System.arraycopy(byteInput, 8, salt, 0, 8);
SecretKeyFactory fact = SecretKeyFactory.getInstance("PBEWITHMD5AND256BITAES-CBC-OPENSSL", "BC");
cipher.init(Cipher.DECRYPT_MODE, fact.generateSecret(new PBEKeySpec(key.toCharArray(), salt, 100)));
byte[] data = cipher.doFinal(byteInput, 16, byteInput.length-16);
OutputStream os = new FileOutputStream(outputFile);
os.write(data);
os.close();
if(outputFile.exists()) {
return outputFile;
} else {
return null;
}
} catch (IOException | NoSuchAlgorithmException | NoSuchProviderException | NoSuchPaddingException | InvalidKeyException | InvalidKeySpecException | IllegalBlockSizeException | BadPaddingException e) {
logger.WriteLog(appConfig.getPlatform(), "INFO", alsConfig.getProjectCode(), correlationId, alsConfig.getFunctionId(), "SCAN_DECRYPT", e.getClass().getCanonicalName() + " - " + e.getMessage() );
return null;
}
}
My non-working version:
Security.addProvider(new BouncyCastleProvider());
String key = new String(Files.readAllBytes(keyFile.toPath())).trim();
byte[] byteInput = this.getFileInBytes(inputFile);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding", "BC");
byte[] salt = new byte[8];
System.arraycopy(byteInput, 8, salt, 0, 8);
SecretKeyFactory fact = SecretKeyFactory.getInstance("PBEWITHMD5AND256BITAES-CBC-OPENSSL", "BC");
cipher.init(Cipher.DECRYPT_MODE, fact.generateSecret(new PBEKeySpec(key.toCharArray(), salt, 100)));
FileInputStream fis = new FileInputStream(inputFile);
FileOutputStream fos = new FileOutputStream(outputFile);
CipherInputStream cis = new CipherInputStream(fis, cipher);
int b;
byte[] d = new byte[8];
while((b = cis.read(d)) != -1) {
fos.write(d, 0, b);
}
fos.flush();
fos.close();
cis.close();
if(outputFile.exists()) {
return outputFile;
} else {
return null;
}

Foreword: I couldn't decrypt with your original method a file that was encrypted with your openssl-command
openssl enc -aes-256-cbc -e -salt -in ${tarFile} -out ${encTarFile} -pass file:./${KEY_RANDOM}
but the following method should decode even large files similar to your original method - I tested files up to 1 GB size.
Edit: Regarding the OpenSSL statement, it's worth mentioning that since v1.1.0 the default digest has changed from MD5 to SHA256,
so for higher versions the -md MD5 option must be set explicitly for compatibility with the Java code. (thanks to #Topaco).
Please keep in mind that I don't care about correct file paths for
new FileInputStream(inputFile.toPath().toString())
and
new FileOutputStream(outputFile.toPath().toString())
as I'm working locally and with my folder, maybe you have to change the code to "find" your files. As well there is no exception handling in this example.
The code line
byte[] ibuf = new byte[8096];
is defining the buffer that is used - a larger buffer makes the decryption faster but consumes more memory (8096 means 8096 byte compared to 1 Gbyte when reading the complete file into memory and causing the out of memory error).
public static File decryptDataFileBuffered(File inputFile, File outputFile, File keyFile, String correlationId) throws IOException, NoSuchPaddingException, NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException, BadPaddingException, IllegalBlockSizeException, InvalidKeyException {
Security.addProvider(new BouncyCastleProvider());
String key = new String(Files.readAllBytes(keyFile.toPath())).trim();
byte[] salt = new byte[8];
byte[] salted = new byte[8]; // text SALTED__
try (FileInputStream in = new FileInputStream(inputFile.toPath().toString()); // i don't care about the path as all is lokal
FileOutputStream out = new FileOutputStream(outputFile.toPath().toString())) // i don't care about the path as all is lokal
{
byte[] ibuf = new byte[8096]; // thats the buffer used - larger is faster
int len;
in.read(salted);
in.read(salt);
SecretKeyFactory fact = SecretKeyFactory.getInstance("PBEWITHMD5AND256BITAES-CBC-OPENSSL", "BC");
SecretKey secretKey = fact.generateSecret(new PBEKeySpec(key.toCharArray(), salt, 100));
System.out.println("secretKey length: " + secretKey.getEncoded().length + " data: " + bytesToHex(secretKey.getEncoded()));
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, secretKey);
while ((len = in.read(ibuf)) != -1) {
byte[] obuf = cipher.update(ibuf, 0, len);
if (obuf != null)
out.write(obuf);
}
byte[] obuf = cipher.doFinal();
if (obuf != null)
out.write(obuf);
} catch (IOException | BadPaddingException | IllegalBlockSizeException e) {
e.printStackTrace();
}
if (outputFile.exists()) {
return outputFile;
} else {
return null;
}
}
Edit2: As commented by #Topaco the usage of CipherInput/OutputStream shortens the code and makes it better readable, so here is the code:
public static File decryptDataFileBufferedCipherInputStream (File inputFile, File outputFile, File keyFile, String correlationId) throws
IOException, NoSuchPaddingException, NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException, InvalidKeyException
{
Security.addProvider(new BouncyCastleProvider());
String key = new String(Files.readAllBytes(keyFile.toPath())).trim();
byte[] salt = new byte[8];
byte[] salted = new byte[8]; // text SALTED__
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
try (FileInputStream in = new FileInputStream(inputFile.toPath().toString()); // i don't care about the path as all is lokal
CipherInputStream cipherInputStream = new CipherInputStream(in, cipher);
FileOutputStream out = new FileOutputStream(outputFile.toPath().toString())) // i don't care about the path as all is lokal
{
byte[] buffer = new byte[8192];
in.read(salted);
in.read(salt);
SecretKeyFactory fact = SecretKeyFactory.getInstance("PBEWITHMD5AND256BITAES-CBC-OPENSSL", "BC");
SecretKey secretKey = fact.generateSecret(new PBEKeySpec(key.toCharArray(), salt, 100));
System.out.println("secretKey length: " + secretKey.getEncoded().length + " data: " + bytesToHex(secretKey.getEncoded()));
cipher.init(Cipher.DECRYPT_MODE, secretKey);
int nread;
while ((nread = cipherInputStream.read(buffer)) > 0) {
out.write(buffer, 0, nread);
}
out.flush();
}
if (outputFile.exists()) {
return outputFile;
} else {
return null;
}
}

Verificiation of a Signature HMAC

I am trying to create a signature then verify for a message of 40 bytes using the SHA-256 algorithm. I thought I did everything correctly, but it is giving me false for verification, and I cannot find out what I did wrong. I double and triple and quadruple checked, but couldn't find out. Any help would be appreciated.
here are the two functions I have created to sign and verify signature for a message.
public static byte[] sigAuth(byte[] message, File file, PrivateKey privateKey) throws NoSuchAlgorithmException, InvalidKeyException, SignatureException, IOException{
SecretKeySpec secretKey = new SecretKeySpec(sharedKey, "hmacSHA256");
Mac macHMAC = Mac.getInstance("HmacSHA256");
macHMAC.init(secretKey);
byte[] authMessageInHMACC = macHMAC.doFinal(message);
Signature signature = Signature.getInstance("SHA256withRSA");
signature.initSign(privateKey);
signature.update(authMessageInHMACC);
byte[] finalSignature = signature.sign();
FileOutputStream fos = new FileOutputStream(file);
fos.write(message);
fos.write(finalSignature);
fos.close();
return finalSignature;
}
public static boolean verify(File file, PublicKey pubKey) throws NoSuchAlgorithmException, InvalidKeyException, SignatureException, IOException{
byte fileContent[] = new byte[(int)sharedKeyFile.length()];
FileInputStream fos = new FileInputStream(file);
fos.read(fileContent);
fos.close();
/Split message from signed hash
byte[] messageOnly = new byte[40];
byte[] hash = new byte[256];
//messageauthmessage
int j = 0;
int k = 0;
for (int i = 0; i < fileContent.length;i++){
if(i < 40){
messageOnly[i] = fileContent[i];
j++;
} else {
hash[k] = fileContent[j+1];
k++;
}
}
SecretKeySpec secretKey = new SecretKeySpec(sharedKey, "hmacSHA256");
Mac macHMAC = Mac.getInstance("HmacSHA256");
macHMAC.init(secretKey);
byte[] authMessageInHMACC = macHMAC.doFinal(messageOnly);
Signature pubSignature = Signature.getInstance("SHA256withRSA");
pubSignature.initVerify(pubKey);
pubSignature.update(authMessageInHMACC);
boolean verified = pubSignature.verify(hash);
return verified;
}

messageOnly[i] = fileContent[i];
should be
messageOnly[j] = fileContent[i];
and
hash[k] = fileContent[j+1];
should be
hash[k] = fileContent[i];

How to store a secretKey in database postgresql and retrieve it

I tried convert it to byte[] and store it on a bytea but it didn't work, i don't receive the same secretkey that i stored. Using type String didn't work as well
if you're interested in more details, my application is to crypt and decrypt pictures using AES and these are methods to crypt and decrypt
public void crypt() throws NoSuchAlgorithmException, NoSuchProviderException, NoSuchPaddingException, InvalidKeyException, IOException{
Cipher cipher = Cipher.getInstance("AES");
KeyGenerator keyGen = KeyGenerator.getInstance("AES");
SecretKey secKey = keyGen.generateKey();
byte[] encoded = secKey.getEncoded();
this.setCodeCrypt(encoded);
cipher.init(Cipher.ENCRYPT_MODE, secKey);
String cleartextFile = this.lien;
String ciphertextFile = "crypted img.jpg";
FileInputStream fis = new FileInputStream(cleartextFile);
FileOutputStream fos = new FileOutputStream(ciphertextFile);
CipherOutputStream cos = new CipherOutputStream(fos, cipher);
int i;
while ((i = fis.read()) != -1) {
cos.write(i);
}
cos.close();
}
// Decrypt
public void decrypt() throws NoSuchAlgorithmException, NoSuchProviderException, NoSuchPaddingException, InvalidKeyException, IOException{
try {
Class.forName("org.postgresql.Driver");
String url = "jdbc:postgresql://localhost:5432/papiersadmin";
String user = "postgres";
String passwd = "postgresql";
java.sql.Connection conn = DriverManager.getConnection(url, user,passwd);
Statement state = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
// loading a picture knowing its path (lien)
ResultSet result = state.executeQuery("SELECT * FROM image WHERE lien = '"+this.lien+"'");
while(result.next()){
setCodeCrypt(result.getObject(6).toString().getBytes());}
state.close();
} catch (Exception e) {
e.printStackTrace();
}
Cipher cipher = Cipher.getInstance("AES");
SecretKey originalKey = new SecretKeySpec(codeCrypt, 0, codeCrypt.length, "AES");
cipher.init(Cipher.DECRYPT_MODE, originalKey);
String cleartextFile = "decrypted img.jpg";
String ciphertextFile = this.lien;
FileInputStream fis = new FileInputStream(ciphertextFile);
FileOutputStream fos = new FileOutputStream(cleartextFile);
CipherOutputStream cos = new CipherOutputStream(fos, cipher);
int i;
while ((i = fis.read()) != -1) {
cos.write(i);
}
cos.close();
}

Converting a byte[] to a String using toString() and then calling getBytes() will not do anything useful. I would suggest starting with ResultSet.getBytes().