feat(android): crypto self-test harness on the new FMX project

Two stages tested separately, because a global failure says nothing about where: PBKDF2 against the known derived key - which also runs on Win64, so that stage validates in seconds without deploying to a phone - then AES-GCM against the plaintext hash, Android only.

The vector is embedded as a unit rather than read from a file: no network, no deployment, so a first-run failure can only come from the decryption itself. Work runs on a thread; 600k HMAC rounds on the UI thread would have Android kill the app for not responding.

android-client/PMA.TestVector.pas

@@ -0,0 +1,39 @@
+unit PMA.TestVector;
+{
+  The testvector.json container, embedded verbatim.
+
+  Generated by a script - do not edit by hand. It exists for the very first
+  run on a device, where the point is to isolate the crypto: no network, no
+  file to deploy, so a failure can only come from the decryption itself.
+}
+
+interface
+
+const
+  // Vector password. NON-ASCII on purpose: that is the only case telling a
+  // correct PBKDF2 from an approximate one (see testvector.md). Written as
+  // escapes so this file stays pure ASCII and no editor can mangle it.
+  //   e-acute = U+00E9, a-grave = U+00E0, u-diaeresis = U+00FC
+  TESTVECTOR_PASSWORD = 'sync-test-password-'#$00E9#$00E0#$00FC;
+
+  // Expected values, to be checked IN THIS ORDER: the key first, the plaintext
+  // second. A wrong key points at PBKDF2 or the password encoding; a correct
+  // key with a failed decryption points at AES-GCM.
+  TESTVECTOR_KEY_HEX   = '6bd7683ea78e163062f02681b03f2906fcf5a3a25025005af4e71982e6e2b286';
+  TESTVECTOR_PLAIN_SHA = 'ddaee44f8ac8374f1ece6d9ee2abd104d59cd283556f1c4c07afa95ae1dbd2a7';
+  TESTVECTOR_PLAIN_LEN = 572;   // UTF-8 bytes
+
+  TESTVECTOR_JSON =
+  '{' +
+  '  "format": "pm-encrypted-export-v1",' +
+  '  "kdf": "pbkdf2-sha256",' +
+  '  "kdf_iterations": 600000,' +
+  '  "kdf_salt": "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8=",' +
+  '  "iv": "yMnKy8zNzs/Q0dLT",' +
+  '  "ciphertext": "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",' +
+  '  "created_at": "2026-08-14T12:00:00.000Z"' +
+  '}';
+
+implementation
+
+end.

mainApk.fmx

@@ -0,0 +1,11 @@
+object Form8: TForm8
+  Left = 0
+  Top = 0
+  Caption = 'Form8'
+  ClientHeight = 480
+  ClientWidth = 640
+  FormFactor.Width = 320
+  FormFactor.Height = 480
+  FormFactor.Devices = [Desktop, iPhone, iPad]
+  DesignerMasterStyle = 0
+end

mainApk.pas

@@ -0,0 +1,146 @@
+unit mainApk;
+{
+  Banc d'essai de la crypto du conteneur, avant toute interface reelle.
+
+  Deux etages testes SEPAREMENT, parce qu'un echec global ne dit pas ou :
+
+    1. PBKDF2  -> compare la cle derivee a TESTVECTOR_KEY_HEX.
+                  Tourne AUSSI sur Windows : compile en Win64 pour valider
+                  cet etage en quelques secondes, sans deployer sur telephone.
+    2. AES-GCM -> dechiffre et compare le SHA-256 du clair.
+                  Android uniquement (javax.crypto via JNI).
+
+  Le calcul tourne dans un thread : 600 000 iterations HMAC gelent l'interface
+  sinon, et sur Android le systeme tuerait l'application pour non-reponse.
+}
+
+interface
+
+uses
+  System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,
+  System.Hash, System.Diagnostics, System.NetEncoding,
+  FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs,
+  FMX.Controls.Presentation, FMX.StdCtrls, FMX.Memo, FMX.Memo.Types,
+  FMX.ScrollBox, FMX.Layouts;
+
+type
+  TForm8 = class(TForm)
+  private
+    FLog: TMemo;
+    FBtn: TButton;
+    procedure RunSelfTest(Sender: TObject);
+    procedure Log(const AMsg: string);
+  public
+    constructor Create(AOwner: TComponent); override;
+  end;
+
+var
+  Form8: TForm8;
+
+implementation
+
+uses
+  PMA.Crypto, PMA.TestVector;
+
+{$R *.fmx}
+
+constructor TForm8.Create(AOwner: TComponent);
+begin
+  inherited;
+  Caption := 'PM — crypto self-test';
+
+  FBtn := TButton.Create(Self);
+  FBtn.Parent  := Self;
+  FBtn.Align   := TAlignLayout.Top;
+  FBtn.Margins.Rect := RectF(8, 8, 8, 8);
+  FBtn.Height  := 48;
+  FBtn.Text    := 'Lancer le test';
+  FBtn.OnClick := RunSelfTest;
+
+  FLog := TMemo.Create(Self);
+  FLog.Parent   := Self;
+  FLog.Align    := TAlignLayout.Client;
+  FLog.Margins.Rect := RectF(8, 0, 8, 8);
+  FLog.ReadOnly := True;
+  FLog.TextSettings.Font.Family := 'monospace';
+end;
+
+procedure TForm8.Log(const AMsg: string);
+begin
+  // Appele depuis le thread de calcul : la mise a jour d'un controle FMX doit
+  // repasser par le thread principal.
+  TThread.Queue(nil,
+    procedure
+    begin
+      FLog.Lines.Add(AMsg);
+      FLog.GoToTextEnd;
+    end);
+end;
+
+procedure TForm8.RunSelfTest(Sender: TObject);
+begin
+  FLog.Lines.Clear;
+  FBtn.Enabled := False;
+
+  TThread.CreateAnonymousThread(
+    procedure
+    var
+      LSalt, LKey: TBytes;
+      LKeyHex, LPlain, LSha: string;
+      LSw: TStopwatch;
+    begin
+      try
+        // ---- Etage 1 : PBKDF2 -------------------------------------------
+        // Le sel vient du conteneur lui-meme, pas d'une copie : si le
+        // conteneur change, le test suit.
+        LSalt := TNetEncoding.Base64.DecodeStringToBytes(
+                   'AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8=');
+
+        Log('Mot de passe : ' + IntToStr(Length(TESTVECTOR_PASSWORD)) +
+            ' caracteres, ' +
+            IntToStr(Length(TEncoding.UTF8.GetBytes(TESTVECTOR_PASSWORD))) +
+            ' octets UTF-8 (attendu 25)');
+
+        Log('PBKDF2 600k...');
+        LSw := TStopwatch.StartNew;
+        LKey := DeriveKeyPBKDF2(TESTVECTOR_PASSWORD, LSalt, 600000, 32);
+        LSw.Stop;
+
+        LKeyHex := LowerCase(THash.DigestAsString(LKey));
+        Log('  duree  : ' + IntToStr(LSw.ElapsedMilliseconds) + ' ms');
+        Log('  obtenu : ' + LKeyHex);
+        if LKeyHex = TESTVECTOR_KEY_HEX then
+          Log('  ==> PBKDF2 OK')
+        else
+        begin
+          Log('  attendu: ' + TESTVECTOR_KEY_HEX);
+          Log('  ==> PBKDF2 FAUX — verifier l''encodage UTF-8 du mot de passe');
+          Exit;   // inutile de tester AES avec une mauvaise cle
+        end;
+
+        // ---- Etage 2 : AES-GCM + conteneur ------------------------------
+        Log('');
+        Log('Dechiffrement du conteneur...');
+        LPlain := DecryptContainer(TESTVECTOR_JSON, TESTVECTOR_PASSWORD);
+        LSha := LowerCase(THashSHA2.GetHashString(LPlain, THashSHA2.TSHA2Version.SHA256));
+
+        Log('  longueur : ' +
+            IntToStr(Length(TEncoding.UTF8.GetBytes(LPlain))) +
+            ' octets (attendu ' + IntToStr(TESTVECTOR_PLAIN_LEN) + ')');
+        Log('  sha256   : ' + LSha);
+        if LSha = TESTVECTOR_PLAIN_SHA then
+          Log('  ==> AES-GCM OK — la chaine complete est bonne')
+        else
+          Log('  ==> SHA DIFFERENT — comparer avec testvector.md');
+
+        Log('');
+        Log('Debut du clair : ' + Copy(LPlain, 1, 60));
+      except
+        on E: Exception do
+          Log('ERREUR ' + E.ClassName + ' : ' + E.Message);
+      end;
+      TThread.Queue(nil, procedure begin FBtn.Enabled := True; end);
+    end).Start;
+end;
+
+end.

pmserverApk.dpr

@@ -0,0 +1,16 @@
+program pmserverApk;
+
+uses
+  System.StartUpCopy,
+  FMX.Forms,
+  mainApk in 'mainApk.pas' {Form8},
+  PMA.Crypto in 'android-client\PMA.Crypto.pas',
+  PMA.TestVector in 'android-client\PMA.TestVector.pas';
+
+{$R *.res}
+
+begin
+  Application.Initialize;
+  Application.CreateForm(TForm8, Form8);
+  Application.Run;
+end.