Nous vous recommandons d'utiliser la primitive AEAD déterministe avec le type de clé AES256_SIV.
Le chiffrement déterministe authentifié avec des données associées (AEAD déterministe) produit des textes chiffrés stables: le chiffrement d'un texte brut donné renvoie toujours le même texte chiffré. Il est symétrique, ce qui signifie qu'il utilise une seule clé pour le chiffrement et le déchiffrement.
Exemples
Les exemples suivants vous aident à utiliser la primitive AEAD déterministe:
C++
// A command-line utility for testing Tink Deterministic AEAD.
#include <iostream>
#include <memory>
#include <ostream>
#include <string>
#include "absl/flags/flag.h"
#include "absl/flags/parse.h"
#include "absl/log/check.h"
#include "absl/strings/string_view.h"
#include "tink/daead/deterministic_aead_config.h"
#include "tink/deterministic_aead.h"
#include "util/util.h"
#include "tink/keyset_handle.h"
#include "tink/util/status.h"
ABSL_FLAG(std::string, keyset_filename, "", "Keyset file in JSON format");
ABSL_FLAG(std::string, mode, "", "Mode of operation {encrypt|decrypt}");
ABSL_FLAG(std::string, input_filename, "", "Filename to operate on");
ABSL_FLAG(std::string, output_filename, "", "Output file name");
ABSL_FLAG(std::string, associated_data, "",
"Associated data for Deterministic AEAD (default: empty");
namespace {
using ::crypto::tink::DeterministicAead;
using ::crypto::tink::DeterministicAeadConfig;
using ::crypto::tink::KeysetHandle;
using ::crypto::tink::util::Status;
using ::crypto::tink::util::StatusOr;
constexpr absl::string_view kEncrypt = "encrypt";
constexpr absl::string_view kDecrypt = "decrypt";
void ValidateParams() {
// ...
}
} // namespace
namespace tink_cc_examples {
// Deterministic AEAD example CLI implementation.
Status DeterministicAeadCli(absl::string_view mode,
const std::string& keyset_filename,
const std::string& input_filename,
const std::string& output_filename,
absl::string_view associated_data) {
Status result = DeterministicAeadConfig::Register();
if (!result.ok()) return result;
// Read keyset from file.
StatusOr<std::unique_ptr<KeysetHandle>> keyset_handle =
ReadJsonCleartextKeyset(keyset_filename);
if (!keyset_handle.ok()) return keyset_handle.status();
// Get the primitive.
StatusOr<std::unique_ptr<DeterministicAead>> daead =
(*keyset_handle)
->GetPrimitive<crypto::tink::DeterministicAead>(
crypto::tink::ConfigGlobalRegistry());
if (!daead.ok()) return daead.status();
// Read the input.
StatusOr<std::string> input_file_content = ReadFile(input_filename);
if (!input_file_content.ok()) return input_file_content.status();
// Compute the output.
std::string output;
if (mode == kEncrypt) {
StatusOr<std::string> result = (*daead)->EncryptDeterministically(
*input_file_content, associated_data);
if (!result.ok()) return result.status();
output = *result;
} else if (mode == kDecrypt) {
StatusOr<std::string> result = (*daead)->DecryptDeterministically(
*input_file_content, associated_data);
if (!result.ok()) return result.status();
output = *result;
}
// Write output to file.
return WriteToFile(output, output_filename);
}
} // namespace tink_cc_examples
int main(int argc, char** argv) {
absl::ParseCommandLine(argc, argv);
ValidateParams();
std::string mode = absl::GetFlag(FLAGS_mode);
std::string keyset_filename = absl::GetFlag(FLAGS_keyset_filename);
std::string input_filename = absl::GetFlag(FLAGS_input_filename);
std::string output_filename = absl::GetFlag(FLAGS_output_filename);
std::string associated_data = absl::GetFlag(FLAGS_associated_data);
std::clog << "Using keyset from file " << keyset_filename
<< " to Deterministic AEAD-" << mode << " file " << input_filename
<< " with associated data '" << associated_data << "'."
<< std::endl;
std::clog << "The resulting output will be written to " << output_filename
<< "." << std::endl;
CHECK_OK(tink_cc_examples::DeterministicAeadCli(
mode, keyset_filename, input_filename, output_filename, associated_data));
return 0;
}
Go
import (
"bytes"
"fmt"
"log"
"github.com/tink-crypto/tink-go/v2/daead"
"github.com/tink-crypto/tink-go/v2/insecurecleartextkeyset"
"github.com/tink-crypto/tink-go/v2/keyset"
)
func Example() {
// A keyset created with "tinkey create-keyset --key-template=AES256_SIV". Note
// that this keyset has the secret key information in cleartext.
jsonKeyset := `{
"key": [{
"keyData": {
"keyMaterialType":
"SYMMETRIC",
"typeUrl":
"type.googleapis.com/google.crypto.tink.AesSivKey",
"value":
"EkAl9HCMmKTN1p3V186uhZpJQ+tivyc4IKyE+opg6SsEbWQ/WesWHzwCRrlgRuxdaggvgMzwWhjPnkk9gptBnGLK"
},
"keyId": 1919301694,
"outputPrefixType": "TINK",
"status": "ENABLED"
}],
"primaryKeyId": 1919301694
}`
// Create a keyset handle from the cleartext keyset in the previous
// step. The keyset handle provides abstract access to the underlying keyset to
// limit the exposure of accessing the raw key material. WARNING: In practice,
// it is unlikely you will want to use a insecurecleartextkeyset, as it implies
// that your key material is passed in cleartext, which is a security risk.
// Consider encrypting it with a remote key in Cloud KMS, AWS KMS or HashiCorp Vault.
// See https://github.com/google/tink/blob/master/docs/GOLANG-HOWTO.md#storing-and-loading-existing-keysets.
keysetHandle, err := insecurecleartextkeyset.Read(
keyset.NewJSONReader(bytes.NewBufferString(jsonKeyset)))
if err != nil {
log.Fatal(err)
}
// Retrieve the DAEAD primitive we want to use from the keyset handle.
primitive, err := daead.New(keysetHandle)
if err != nil {
log.Fatal(err)
}
// Use the primitive to encrypt a message. In this case the primary key of the
// keyset will be used (which is also the only key in this example).
plaintext := []byte("message")
associatedData := []byte("associated data")
ciphertext, err := primitive.EncryptDeterministically(plaintext, associatedData)
if err != nil {
log.Fatal(err)
}
// Use the primitive to decrypt the message. Decrypt finds the correct key in
// the keyset and decrypts the ciphertext. If no key is found or decryption
// fails, it returns an error.
decrypted, err := primitive.DecryptDeterministically(ciphertext, associatedData)
if err != nil {
log.Fatal(err)
}
fmt.Println(ciphertext)
fmt.Println(string(decrypted))
// Output:
// [1 114 102 56 62 150 98 146 84 99 211 36 127 214 229 231 157 56 143 192 250 132 32 153 124 244 238 112]
// message
}
Java
package deterministicaead;
import static java.nio.charset.StandardCharsets.UTF_8;
import com.google.crypto.tink.DeterministicAead;
import com.google.crypto.tink.InsecureSecretKeyAccess;
import com.google.crypto.tink.KeysetHandle;
import com.google.crypto.tink.TinkJsonProtoKeysetFormat;
import com.google.crypto.tink.daead.DeterministicAeadConfig;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
/**
* A command-line utility for encrypting small files with Deterministic AEAD.
*
* <p>It loads cleartext keys from disk - this is not recommended!
*
* <p>It requires the following arguments:
*
* <ul>
* <li>mode: Can be "encrypt" or "decrypt" to encrypt/decrypt the input to the output.
* <li>key-file: Read the key material from this file.
* <li>input-file: Read the input from this file.
* <li>output-file: Write the result to this file.
* <li>[optional] associated-data: Associated data used for the encryption or decryption.
*/
public final class DeterministicAeadExample {
private static final String MODE_ENCRYPT = "encrypt";
private static final String MODE_DECRYPT = "decrypt";
public static void main(String[] args) throws Exception {
if (args.length != 4 && args.length != 5) {
System.err.printf("Expected 4 or 5 parameters, got %d\n", args.length);
System.err.println(
"Usage: java DeterministicAeadExample encrypt/decrypt key-file input-file output-file"
+ " [associated-data]");
System.exit(1);
}
String mode = args[0];
Path keyFile = Paths.get(args[1]);
Path inputFile = Paths.get(args[2]);
Path outputFile = Paths.get(args[3]);
byte[] associatedData = new byte[0];
if (args.length == 5) {
associatedData = args[4].getBytes(UTF_8);
}
// Initialise Tink: register all Deterministic AEAD key types with the Tink runtime
DeterministicAeadConfig.register();
// Read the keyset into a KeysetHandle
KeysetHandle handle =
TinkJsonProtoKeysetFormat.parseKeyset(
new String(Files.readAllBytes(keyFile), UTF_8), InsecureSecretKeyAccess.get());
// Get the primitive
DeterministicAead daead = handle.getPrimitive(DeterministicAead.class);
// Use the primitive to encrypt/decrypt files.
if (MODE_ENCRYPT.equals(mode)) {
byte[] plaintext = Files.readAllBytes(inputFile);
byte[] ciphertext = daead.encryptDeterministically(plaintext, associatedData);
Files.write(outputFile, ciphertext);
} else if (MODE_DECRYPT.equals(mode)) {
byte[] ciphertext = Files.readAllBytes(inputFile);
byte[] plaintext = daead.decryptDeterministically(ciphertext, associatedData);
Files.write(outputFile, plaintext);
} else {
System.err.println("The first argument must be either encrypt or decrypt, got: " + mode);
System.exit(1);
}
System.exit(0);
}
private DeterministicAeadExample() {}
}
Python
import tink
from tink import daead
from tink import secret_key_access
def example():
"""Encrypt and decrypt using deterministic AEAD."""
# Register the deterministic AEAD key manager. This is needed to create a
# DeterministicAead primitive later.
daead.register()
# A keyset created with "tinkey create-keyset --key-template=AES256_SIV". Note
# that this keyset has the secret key information in cleartext.
keyset = r"""{
"key": [{
"keyData": {
"keyMaterialType":
"SYMMETRIC",
"typeUrl":
"type.googleapis.com/google.crypto.tink.AesSivKey",
"value":
"EkAl9HCMmKTN1p3V186uhZpJQ+tivyc4IKyE+opg6SsEbWQ/WesWHzwCRrlgRuxdaggvgMzwWhjPnkk9gptBnGLK"
},
"keyId": 1919301694,
"outputPrefixType": "TINK",
"status": "ENABLED"
}],
"primaryKeyId": 1919301694
}"""
# Create a keyset handle from the cleartext keyset in the previous
# step. The keyset handle provides abstract access to the underlying keyset to
# limit the exposure of accessing the raw key material. WARNING: In practice,
# it is unlikely you will want to use a cleartext_keyset_handle, as it implies
# that your key material is passed in cleartext which is a security risk.
keyset_handle = tink.json_proto_keyset_format.parse(
keyset, secret_key_access.TOKEN
)
# Retrieve the DeterministicAead primitive we want to use from the keyset
# handle.
primitive = keyset_handle.primitive(daead.DeterministicAead)
# Use the primitive to encrypt a message. In this case the primary key of the
# keyset will be used (which is also the only key in this example).
ciphertext = primitive.encrypt_deterministically(b'msg', b'associated_data')
# Use the primitive to decrypt the message. Decrypt finds the correct key in
# the keyset and decrypts the ciphertext. If no key is found or decryption
# fails, it raises an error.
output = primitive.decrypt_deterministically(ciphertext, b'associated_data')