SecureString Chilkat2 PHP Reference Documentation

SecureString

Current Version: 11.7.0

Markdown version of this page for AI tools (v 11.7.0) · all AI docs

Chilkat.SecureString

Store, append, compare, hash, verify, and securely access sensitive string values.

Chilkat.SecureString holds sensitive text in an encrypted in-memory form while still allowing controlled operations on the value. It can append clear-text strings, append text from a StringBuilder, append another SecureString, load text from a file, return the clear-text value when needed, compare secure strings, mark the value read-only, maintain a hash of the current value, and verify a supplied hash against that maintained value.

Encrypted in-memory value

Store sensitive text in a form that is decrypted only when needed for access, modification, comparison, or hashing.

Append safely

Append clear-text strings, StringBuilder content, or another SecureString; the value is then re-encrypted.

Read-only protection

Set ReadOnly to prevent later modification of the secure string.

Hash maintenance

Set MaintainHash to a supported hash algorithm such as sha256, sha512, sha1, or md5.

Hash output and verification

Retrieve the current hash value in an encoding such as hex or Base64, or verify a supplied encoded hash with VerifyHash.

Compare and access

Compare two secure strings with SecStrEquals, or call Access when the clear-text value is required.

Common pattern: Create a SecureString, load or append the sensitive text, set MaintainHash if later verification is needed, and optionally set ReadOnly after the final value is established. Use Access only at the point where the clear-text string is actually needed, and check LastErrorText if an append, file load, hash, or verification operation fails.
Hash note: VerifyHash depends on MaintainHash having already been set so the object maintains an internal hash for the current secure string value.

Object Creation

use Chilkat2\SecureString;

try {
    $secureString = new SecureString();
    // ... use $secureString ...
} catch (\Chilkat2\Exception $e) {
    echo $e->getClass(), '::', $e->getMethod(), " failed\n";
    echo $e->getMessage(), "\n";              // the LastErrorText of the failed call
}
public function __construct(array $properties = [])

Creates the object. The optional array sets properties in order, as if assigned one by one (new SecureString(['VerboseLogging' => true, 'RaiseError' => false])); an unknown or read-only name throws Error. The class is defined by the chilkat2 extension (extension=chilkat2 in php.ini): there is no PHP file to include.

There is no close(): PHP frees the object when its last reference goes (unset($secureString), $secureString = null, or the end of the function or request). Objects returned by methods are independent and freed the same way. The class may be extended (class MySecureString extends \Chilkat2\SecureString); objects cannot be cloned or serialized.

public bool $RaiseError;

When true (the default), a method that fails throws Chilkat2\Exception. When false, it returns false (or null) instead, and the reason is in LastErrorText. Objects returned by a method inherit the value of the object that returned them.

Errors

Chilkat2\Exception extends RuntimeException: getMessage() is the failed call's full LastErrorText, getClass() its class ('Chilkat2\SecureString') and getMethod() the method name. The object remains usable. Methods that look something up and find nothing return null without throwing (each such method says so), methods that answer a question (HasMember, IsUnlocked, ...) return a plain bool, and property reads and writes do not throw for Chilkat reasons.

Misuse always throws, whatever RaiseError is: a wrong argument type is a TypeError (exact types under declare(strict_types=1)), a missing or extra argument an ArgumentCountError, a string containing a NUL byte or an out-of-range integer a ValueError, and an unknown property (properties are case-sensitive) or a write to a read-only one an Error. Named arguments work with the parameter names shown.

Strings are passed and returned as UTF-8; binary data is a PHP string of bytes. Unlocking: call (new \Chilkat2\GlobalSettings())->UnlockBundle('...') once at startup.

Properties

DebugLogFilePath
public string $DebugLogFilePath;

If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.

Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.

Possible causes of hangs include:

  • A timeout property set to 0, indicating an infinite timeout.
  • A hang occurring within an event callback in the application code.
  • An internal bug in the Chilkat code causing the hang.

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LastErrorHtml
public readonly string $LastErrorHtml;

Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastErrorText
public readonly string $LastErrorText;

Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastErrorXml
public readonly string $LastErrorXml;

Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastMethodSuccess
public bool $LastMethodSuccess;

Indicates the success or failure of the most recent method call: true means success, false means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.

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MaintainHash
public string $MaintainHash;
Introduced in version 9.5.0.71

If set to the name of a hash algorithm, then a hash of the current string value is maintained. This allows for the hash to be verified via the VerifyHash method. Possible hash algorithm names are sha1, sha256, sha384, sha512, md5, md2, ripemd160, ripemd128,ripemd256, and ripemd320.

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ReadOnly
public bool $ReadOnly;
Introduced in version 9.5.0.71

Can be set to true to make this secure string read-only (cannot be modified).

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VerboseLogging
public bool $VerboseLogging;

If set to true, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is false. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

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Version
public readonly string $Version;

Version of the component/library, such as "10.1.0"

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Methods

Access
public function Access(): ?string
Introduced in version 9.5.0.71

Returns the clear-text string value.

On failure it throws Chilkat2\Exception (or, with RaiseError set to false, returns null). $e->getMessage() (or the object's LastErrorText) explains why, and the object remains usable.

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Append
public function Append(string $str): bool
Introduced in version 9.5.0.71

Appends a clear-text string to this secure string. The in-memory data will be decrypted, the string will be appended, and then it will be re-encrypted. Can return false if the string has been marked as read-only via the ReadOnly property.

Returns true on success. On failure it throws Chilkat2\Exception (or, with RaiseError set to false, returns false). $e->getMessage() (or the object's LastErrorText) explains why, and the object remains usable.

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AppendSb
public function AppendSb(StringBuilder $sb): bool
Introduced in version 9.5.0.71

Appends a clear-text string contained in a StringBuilder to this secure string. The in-memory data will be decrypted, the string will be appended, and then it will be re-encrypted. Can return false if the string has been marked as read-only via the ReadOnly property.

Returns true on success. On failure it throws Chilkat2\Exception (or, with RaiseError set to false, returns false). $e->getMessage() (or the object's LastErrorText) explains why, and the object remains usable.

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AppendSecure
public function AppendSecure(SecureString $secStr): bool
Introduced in version 9.5.0.71

Appends the contents of a secure string to this secure string. The in-memory data will be decrypted, the secure string will be appended, and then it will be re-encrypted. Can return false if this string has been marked as read-only via the ReadOnly property.

Returns true on success. On failure it throws Chilkat2\Exception (or, with RaiseError set to false, returns false). $e->getMessage() (or the object's LastErrorText) explains why, and the object remains usable.

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HashVal
public function HashVal(string $encoding): ?string
Introduced in version 9.5.0.71

Returns the hash value for the current value of this secure string. The $encoding specifies the encoding to be used. It can be any of the binary encoding algorithms, such as base64, hex, and many more listed at Chilkat Binary Encodings

On failure it throws Chilkat2\Exception (or, with RaiseError set to false, returns null). $e->getMessage() (or the object's LastErrorText) explains why, and the object remains usable.

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LoadFile
public function LoadFile(string $path, string $charset): bool
Introduced in version 9.5.0.71

Loads the contents of a file into this secure string. The current contents of this object are replaced with the new text from the file.

Returns true on success. On failure it throws Chilkat2\Exception (or, with RaiseError set to false, returns false). $e->getMessage() (or the object's LastErrorText) explains why, and the object remains usable.

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SecStrEquals
public function SecStrEquals(SecureString $secStr): bool
Introduced in version 9.5.0.71

Returns true if the $secStr equals the contents of this secure string.

Returns true on success. On failure it throws Chilkat2\Exception (or, with RaiseError set to false, returns false). $e->getMessage() (or the object's LastErrorText) explains why, and the object remains usable.

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VerifyHash
public function VerifyHash(string $hashVal, string $encoding): bool
Introduced in version 9.5.0.71

Verifies the $hashVal against the hash value stored for the current value of this secure string. The MaintainHash property must've previously been set for this secure string to maintain an internal hash. The $encoding specifies the encoding of the $hashVal. It can be any of the binary encoding algorithms, such as base64, hex, and many more listed at Chilkat Binary Encodings

Returns true on success. On failure it throws Chilkat2\Exception (or, with RaiseError set to false, returns false). $e->getMessage() (or the object's LastErrorText) explains why, and the object remains usable.

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