SecureString SQL Server Reference Documentation
SecureString
Current Version: 11.6.0
Chilkat.SecureString
Store sensitive text in a form that is decrypted only when needed for
access, modification, comparison, or hashing.
Append clear-text strings,
Set
Set
Retrieve the current hash value in an encoding such as hex or Base64, or
verify a supplied encoded hash with
Compare two secure strings with 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
Append safely
StringBuilder content, or another
SecureString; the value is then re-encrypted.
Read-only protection
ReadOnly to prevent later modification of the secure
string.
Hash maintenance
MaintainHash to a supported hash algorithm such as
sha256, sha512, sha1, or
md5.
Hash output and verification
VerifyHash.
Compare and access
SecStrEquals, or call
Access when the clear-text value is required.
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.
VerifyHash depends on MaintainHash having already
been set so the object maintains an internal hash for the current secure
string value.
Object Creation
DECLARE @hr int
DECLARE @secureString int
EXEC @hr = sp_OACreate 'Chilkat.SecureString', @secureString OUT
IF @hr <> 0
BEGIN
PRINT 'Failed to create ActiveX component'
RETURN
END
-- ... use @secureString ...
EXEC @hr = sp_OADestroy @secureStringT-SQL uses the Chilkat ActiveX through the OLE Automation stored procedures. They must be enabled once on the server (EXEC sp_configure 'Ole Automation Procedures', 1; RECONFIGURE;), and the Chilkat ActiveX registered must match the bitness of the SQL Server instance (64-bit for a 64-bit SQL Server). To bind to a specific major version of Chilkat, append the major version number to the ProgID, such as sp_OACreate 'Chilkat.SecureString.11' for Chilkat v11.*.*.
sp_OACreate returns an object token (an int) that is passed as the first argument of every sp_OAMethod, sp_OAGetProperty and sp_OASetProperty call, and released with sp_OADestroy. Objects returned by methods (such as an HttpResponse or JsonObject) are also tokens received through an int OUT parameter; they must likewise be destroyed, and the OUT parameter is NULL when the method fails to return an object. Objects passed as arguments are passed by their token. When an OLE Automation procedure itself fails (non-zero @hr), sp_OAGetErrorInfo describes the error.
Data types: strings are nvarchar(4000); integers, booleans (1 or 0) and object tokens are int; dates are datetime. In the signatures on this page, @success, @iResult, @sResult and the like are the OUT variables receiving a method's return value, @iValue / @sValue receive or supply a property value, and the remaining @ variables are the method's arguments in order.
A string returned through an OUT parameter is limited to 4000 characters. For longer values, retrieve the result as a result set into a table variable instead of an OUT parameter, for example DECLARE @tmp TABLE (outputLine ntext) followed by INSERT INTO @tmp EXEC sp_OAGetProperty @secureString, 'LastErrorText'. See string length limitations for strings returned by sp_OAMethod calls.
Methods that pass or return raw byte arrays are not shown on this page, because varbinary(max) values cannot be exchanged through sp_OAMethod (see varbinary(max) limitation). Use the BinData-based alternatives (methods ending in Bd) or the base64 / hex string-encoded variants instead. Binary properties (such as LastBinaryResult) can be retrieved as a result set into a table variable, as shown in their signatures. Asynchronous (*Async) methods and event callbacks are not available from SQL Server.
Properties
DebugLogFilePath
EXEC sp_OASetProperty @secureString, 'DebugLogFilePath', @sValue
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.
LastBinaryResult
This property is mainly used in SQL Server stored procedures to retrieve binary data from the last method call that returned binary data. It is only accessible if Chilkat.Global.KeepBinaryResult is set to 1. This feature allows for the retrieval of large varbinary results in an SQL Server environment, which has restrictions on returning large data via method calls, though temp tables can handle binary properties.
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.
topLastErrorText
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.
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.
topLastMethodSuccess
EXEC sp_OASetProperty @secureString, 'LastMethodSuccess', @iValue
Indicates the success or failure of the most recent method call: 1 means success, 0 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.
LastStringResult
In SQL Server stored procedures, this property holds the string return value of the most recent method call that returns a string. It is accessible only when Chilkat.Global.KeepStringResult is set to TRUE. SQL Server has limitations on string lengths returned from methods and properties, but temp tables can be used to access large strings.
LastStringResultLen
The length, in characters, of the string contained in the LastStringResult property.
topMaintainHash
EXEC sp_OASetProperty @secureString, 'MaintainHash', @sValue
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.
ReadOnly
EXEC sp_OASetProperty @secureString, 'ReadOnly', @iValue
Can be set to 1 to make this secure string read-only (cannot be modified).
VerboseLogging
EXEC sp_OASetProperty @secureString, 'VerboseLogging', @iValue
If set to 1, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is 0. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
Version
Methods
Access
Append
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 0 if the string has been marked as read-only via the ReadOnly property.
Returns 1 for success, 0 for failure.
topAppendSb
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 0 if the string has been marked as read-only via the ReadOnly property.
Returns 1 for success, 0 for failure.
topAppendSecure
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 0 if this string has been marked as read-only via the ReadOnly property.
HashVal
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
Returns NULL on failure
LoadFile
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 1 for success, 0 for failure.
topSecStrEquals
Returns 1 if the secStr equals the contents of this secure string.
Returns 1 for success, 0 for failure.
topVerifyHash
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 1 for success, 0 for failure.
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