c.lock.RLock()
	defer c.lock.RUnlock()

	plaintexts := make([][]byte, 0, len(ciphertexts))
	for i := range ciphertexts {
		ctxBytes, err := contexts[i].MarshalText()
		if err != nil {
			return nil, err
		}
		plaintext, err := c.client.Decrypt(ctx, keyID, ciphertexts[i], ctxBytes)
		if err != nil {
			return nil, err
		}
		plaintexts = append(plaintexts, plaintext)
	}
	return plaintexts, nil
}

var decryptTests = []struct {
	Key       []byte
	ETag      ETag
	Plaintext ETag
}{
	{ // 0
		Key:       make([]byte, 32),
		ETag:      must("3b83ef96387f14655fc854ddc3c6bd57"),
		Plaintext: must("3b83ef96387f14655fc854ddc3c6bd57"),
	},
	{ // 1
		Key:       make([]byte, 32),
		ETag:      must("7b976cc68452e003eec7cb0eb631a19a-1"),
		Plaintext: must("7b976cc68452e003eec7cb0eb631a19a-1"),
	},
	{ // 2

##### Figure 1 - Secure Channel construction

```
plaintext   := chunk_0          ||       chunk_1          ||       chunk_2          ||       ...

          //
          // Raw write
          // Raw read
          // Plaintext before ENCRYPTION
          // Plaintext after DECRYPTION
          val message = record.message
          val parameters = record.parameters

          if (parameters != null && !message.startsWith("Raw") && !message.startsWith("Plaintext")) {
            if (verbose) {
              println(record.message)

	if !etag.IsEncrypted() {
		return etag, nil
	}
	mac := hmac.New(sha256.New, key)
	mac.Write([]byte(HMACContext))
	decryptionKey := mac.Sum(nil)

	plaintext := make([]byte, 0, 16)
	etag, err := sio.DecryptBuffer(plaintext, etag, sio.Config{
		Key:          decryptionKey,
		CipherSuites: fips.DARECiphers(),
	})
	if err != nil {
		return nil, err
	}
	return etag, nil
}

		key, err := GlobalKMS.GenerateKey(ctx, "", kms.Context{bucket: path.Join(bucket, object)})
		if err != nil {
			return crypto.ObjectKey{}, err
		}

		objectKey := crypto.GenerateKey(key.Plaintext, rand.Reader)
		sealedKey = objectKey.Seal(key.Plaintext, crypto.GenerateIV(rand.Reader), crypto.S3.String(), bucket, object)
		crypto.S3.CreateMetadata(metadata, key.KeyID, key.Ciphertext, sealedKey)
		return objectKey, nil
	case crypto.S3KMS:

	key, err := GlobalKMS.GenerateKey(ctx, "", kmsContext)
	if err != nil {
		return
	}

	outbuf := bytes.NewBuffer(nil)
	objectKey := crypto.GenerateKey(key.Plaintext, rand.Reader)
	sealedKey := objectKey.Seal(key.Plaintext, crypto.GenerateIV(rand.Reader), crypto.S3.String(), bucket, "")
	crypto.S3.CreateMetadata(metadata, key.KeyID, key.Ciphertext, sealedKey)

### Check the password

At this point we have the user data from our database, but we haven't checked the password.

Let's put that data in the Pydantic `UserInDB` model first.

You should never save plaintext passwords, so, we'll use the (fake) password hashing system.

If the passwords don't match, we return the same error.

#### Password hashing

But you cannot convert from the gibberish back to the password.

### Why use password hashing

If your database is stolen, the thief won't have your users' plaintext passwords, only the hashes.

So, the thief won't be able to try to use that password in another system (as many users use the same password everywhere, this would be dangerous).

## Install `passlib`

## Return the same input data

Here we are declaring a `UserIn` model, it will contain a plaintext password:

=== "Python 3.10+"

    ```Python hl_lines="7  9"
    {!> ../../../docs_src/response_model/tutorial002_py310.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="9  11"