NEW Generate a random password if a blank password is entered

lang/en.yml

@@ -36,6 +36,7 @@ en:
   SilverStripe\Forms\ConfirmedPasswordField:
     ATLEAST: 'Passwords must be at least {min} characters long.'
     BETWEEN: 'Passwords must be {min} to {max} characters long.'
+    RANDOM_IF_EMPTY: 'If this is left blank then a random password will be automatically generated. The user will need to click the forgotten password link to generate a reset password email so they can set their own password.'
     CURRENT_PASSWORD_ERROR: 'The current password you have entered is not correct.'
     CURRENT_PASSWORD_MISSING: 'You must enter your current password.'
     LOGGED_IN_ERROR: 'You must be logged in to change your password.'

src/Forms/ConfirmedPasswordField.php

@@ -2,11 +2,14 @@
 
 namespace SilverStripe\Forms;
 
+use Exception;
+use LogicException;
 use SilverStripe\ORM\DataObject;
 use SilverStripe\ORM\DataObjectInterface;
 use SilverStripe\Security\Authenticator;
 use SilverStripe\Security\Security;
 use SilverStripe\View\HTML;
+use SilverStripe\Security\Member;
 
 /**
  * Two masked input fields, checks for matching passwords.
@@ -43,12 +46,26 @@ class ConfirmedPasswordField extends FormField
     public $requireStrongPassword = false;
 
     /**
-     * Allow empty fields in serverside validation
+     * Allow empty fields in when entering the password for the first time
+     * If this is set to true then a random password may be generated if the field is empty
+     * depending on the value of $self::generateRandomPasswordOnEmtpy
      *
      * @var boolean
      */
     public $canBeEmpty = false;
 
+    private bool $generateRandomPasswordOnEmpty = false;
+
+    /**
+     * Callback to generate a random password
+     *
+     * Note: cannot strongly type a callable property so need to use docblock typing instead
+     * https://wiki.php.net/rfc/typed_properties_v2
+     *
+     * @var callable|null
+     */
+    private $randomPasswordCallback = null;
+
     /**
      * If set to TRUE, the "password" and "confirm password" form fields will
      * be hidden via CSS and JavaScript by default, and triggered by a link.
@@ -255,7 +272,36 @@ public function getChildren()
     public function setCanBeEmpty($value)
     {
         $this->canBeEmpty = (bool)$value;
+        $this->updateRightTitle();
+        return $this;
+    }
 
+    public function getGenerateRandomPasswordOnEmpty(): bool
+    {
+        return $this->generateRandomPasswordOnEmpty;
+    }
+
+    public function setGenerateRandomPasswordOnEmpty(bool $generateRandomPasswordOnEmpty): static
+    {
+        $this->generateRandomPasswordOnEmpty = $generateRandomPasswordOnEmpty;
+        $this->updateRightTitle();
+        return $this;
+    }
+
+    /**
+     * @return callable|null
+     */
+    public function getRandomPasswordCallback()
+    {
+        return $this->randomPasswordCallback;
+    }
+
+    /**
+     * @param callable|null $randomPasswordCallback
+     */
+    public function setRandomPasswordCallback($randomPasswordCallback): static
+    {
+        $this->randomPasswordCallback = $randomPasswordCallback;
         return $this;
     }
 
@@ -552,8 +598,6 @@ public function validate($validator)
     }
 
     /**
-     * Only save if field was shown on the client, and is not empty.
-     *
      * @param DataObjectInterface $record
      */
     public function saveInto(DataObjectInterface $record)
@@ -562,9 +606,18 @@ public function saveInto(DataObjectInterface $record)
             return;
         }
 
-        if (!($this->canBeEmpty && !$this->value)) {
-            parent::saveInto($record);
+        // Create a random password for Member if password is blank
+        if (!$this->value
+            && $this->canBeEmpty
+            && $this->generateRandomPasswordOnEmpty
+        ) {
+            if (!is_callable($this->randomPasswordCallback)) {
+                throw new LogicException('randomPasswordCallback must be callable');
+            }
+            $this->value = call_user_func($this->randomPasswordCallback, ['maxLength' => $this->maxLength]);
         }
+
+        parent::saveInto($record);
     }
 
     /**
@@ -694,4 +747,17 @@ public function getRequireStrongPassword()
     {
         return $this->requireStrongPassword;
     }
+
+    private function updateRightTitle(): void
+    {
+        $text = _t(
+            __CLASS__ . '.RANDOM_IF_EMPTY',
+            'If this is left blank then a random password will be automatically generated. The user will need to click the forgotten password link to generate a reset password email so they can set their own password.'
+        );
+        if ($this->canBeEmpty && $this->generateRandomPasswordOnEmpty) {
+            $this->passwordField->setRightTitle($text);
+        } elseif ($this->passwordField->RightTitle() === $text) {
+            $this->passwordField->setRightTitle('');
+        }
+    }
 }

src/Security/Member.php

@@ -2,6 +2,7 @@
 
 namespace SilverStripe\Security;
 
+use Exception;
 use IntlDateFormatter;
 use InvalidArgumentException;
 use SilverStripe\Admin\LeftAndMain;
@@ -670,7 +671,14 @@ public function getMemberPasswordField()
             $password->setRequireExistingPassword(true);
         }
 
-        $password->setCanBeEmpty(false);
+        if (!$editingPassword) {
+            $password->setCanBeEmpty(true);
+            $password->setGenerateRandomPasswordOnEmpty(true);
+            $password->setRandomPasswordCallback([__CLASS__, 'generateRandomPassword']);
+            // explicitly set "require strong password" to false because its regex in ConfirmedPasswordField
+            // is too restrictive for generateRandomPassword() which will add in non-alphanumeric characters
+            $password->setRequireStrongPassword(false);
+        }
         $this->extend('updateMemberPasswordField', $password);
 
         return $password;
@@ -1702,4 +1710,46 @@ public function getHtmlEditorConfigForCMS()
         // If can't find a suitable editor, just default to cms
         return $currentName ? $currentName : 'cms';
     }
+
+    /**
+     * This needs to be public because it's referenced in getMemberPasswordField() and called in ConfirmedPasswordField
+     */
+    public static function generateRandomPassword(array $args = []): string
+    {
+        $password = '';
+        $validator = self::password_validator();
+        $minLength = $validator ? $validator->getMinLength() : 20;
+        $maxLength = $args['maxLength'] ?? 0;
+        if ($maxLength === 0) {
+            $maxLength = max($minLength, 20);
+        } else {
+            if ($maxLength < $minLength) {
+                throw new InvalidArgumentException('maxLength argument is less than PasswordValidator minLength');
+            }
+        }
+        $dummyMember = new Member();
+        // These are similar character sets that used in the default PasswordValidator
+        $lc = 'abcdefghijklmnopqrstuvwyxz';
+        $uc = strtoupper($lc);
+        $num = '0123456789';
+        $pun = '!@#$%^&*()_+-=[]{};:,./<>?';
+        $chars = $lc . $uc . $num . $pun;
+        $c = 0;
+        do {
+            $valid = true;
+            $password = '';
+            for ($i = 0; $i < $maxLength; $i++) {
+                $randomInt = random_int(0, strlen($chars) - 1);
+                $password .= $chars[$randomInt];
+            }
+            if ($validator && !$validator->validate($password, $dummyMember)) {
+                $valid = false;
+            }
+            if (++$c === 100) {
+                // protection against infinite while loop
+                throw new Exception('Unable to generate a random password');
+            }
+        } while (!$valid);
+        return $password;
+    }
 }

tests/php/Forms/ConfirmedPasswordFieldTest.php

@@ -381,4 +381,46 @@ public function testSetRequireExistingPasswordOnlyRunsOnce()
         $field->setRequireExistingPassword(false);
         $this->assertCount(2, $field->getChildren(), 'Current password field should not be removed');
     }
+
+    /**
+     * @dataProvider provideSetCanBeEmptySaveInto
+     */
+    public function testSetCanBeEmptySaveInto(bool $generateRandomPasswordOnEmpty, ?string $expected)
+    {
+        $field = new ConfirmedPasswordField('Test', 'Change it');
+        $field->setCanBeEmpty(true);
+        $field->setGenerateRandomPasswordOnEmpty($generateRandomPasswordOnEmpty);
+        $field->setRandomPasswordCallback(function () {
+            return 'R4ndom-P4ssw0rd$LOREM^ipsum#12345';
+        });
+        $this->assertEmpty($field->Value());
+        $member = new Member();
+        $field->saveInto($member);
+        $this->assertSame($expected, $field->Value());
+    }
+
+    public function provideSetCanBeEmptySaveInto(): array
+    {
+        return [
+            [
+                'generateRandomPasswordOnEmpty' => true,
+                'expected' => 'R4ndom-P4ssw0rd$LOREM^ipsum#12345',
+            ],
+            [
+                'generateRandomPasswordOnEmpty' => false,
+                'expected' => null,
+            ],
+        ];
+    }
+
+    public function testSetCanBeEmptyRightTitle()
+    {
+        $field = new ConfirmedPasswordField('Test', 'Change it');
+        $passwordField = $field->getPasswordField();
+        $this->assertEmpty($passwordField->RightTitle());
+        $field->setCanBeEmpty(true);
+        $this->assertEmpty($passwordField->RightTitle());
+        $field->setGenerateRandomPasswordOnEmpty(true);
+        $this->assertNotEmpty($passwordField->RightTitle());
+    }
 }

tests/php/Security/MemberTest.php

@@ -1896,4 +1896,25 @@ public function provideMapInCMSGroups()
             ],
         ];
     }
+
+    public function testGenerateRandomPassword()
+    {
+        $validator = new PasswordValidator();
+        Member::set_password_validator($validator);
+        // Password length of 20 even if validator minLength is less than 20
+        $validator->setMinLength(10);
+        $password = Member::generateRandomPassword();
+        $this->assertSame(20, strlen($password));
+        // Password length of 25 if passing maxLength argument, and validator minlength is less than maxLength argument
+        $password = Member::generateRandomPassword(['maxLength' => 25]);
+        $this->assertSame(25, strlen($password));
+        // Password length is validator minLength if validator minLength is greater than 20 and no maxLength argument
+        $validator->setMinLength(30);
+        $password = Member::generateRandomPassword();
+        $this->assertSame(30, strlen($password));
+        // Exception throw if maxLength argument is less than validator minLength
+        $this->expectException(InvalidArgumentException::class);
+        $this->expectExceptionMessage('maxLength argument is less than PasswordValidator minLength');
+        $password = Member::generateRandomPassword(['maxLength' => 25]);
+    }
 }