TChilkatDsa Delphi ActiveX Reference Documentation

TChilkatDsa

The Digital Signature Algorithm (DSA) is a United States Federal Government standard or FIPS for digital signatures. It was proposed by the National Institute of Standards and Technology (NIST) in August 1991 for use in their Digital Signature Standard (DSS).

Importing the Chilkat ActiveX into Delphi

Important: Whenever upgrading to a new version of Chilkat, make sure to re-imported ActiveX DLL into Delphi to regenerate the files described below.

Two things are required to use an ActiveX in Delphi:

  1. The ActiveX DLL needs to be registered via regsvr32 on the system where the Delphi application runs. See How To Register ActiveX DLLs for detailed information.
  2. The ActiveX component needs to be "imported". Use the Delphi Import Component Wizard to import the Chilkat type library. This creates the following files: Chilkat_v9_5_0_TLB.pas and Chilkat_v9_5_0_TLB.dcr. The Chilkat_v9_5_0_TLB.pas should be added to your project.

To import the Chilkat type library, do the following:

  1. In the Delphi RAD Studio, select the menu item "Component" --> "Import a Type Library".
  2. Find "Chilkat ActiveX v9.5.0" in the list and select it. This will only appear in the list if the ChilkatAx-9.5.0-win32.dll (or ChilkatAx-9.5.0-x64.dll) has been registered w/ regsvr32.
  3. Check the "Generate Component Wrappers" checkbox.
  4. Select a directory where the unit files (.pas and .dcr) will be generated.
  5. Select "Create Unit" and then "Finish".
  6. Add the .pas to your Delphi project.

To use a Chilkat ActiveX object in your Delphi code, add "Chilkat_v9_5_0_TLB" to the "uses" statement. For example:

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_v9_5_0_TLB;

Object Creation

var
obj: TChilkatDsa;
...
begin
obj := TChilkatDsa.Create(Self);
...
// When finished, free the object instance.
obj.Free();

Properties

property DebugLogFilePath: WideString

If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.

This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:

  1. a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
  2. the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
  3. there is an internal problem (bug) in the Chilkat code that causes the hang.

property GroupSize: Integer

The group size (in bits) to be used in DSA key generation. The default value is 160 and corresponds to the fact that SHA-1 is used in signature generation. This property setting should not be changed. It exists for future expansion when additional underlying hash algorithms are supported.

property Hash: OleVariant

The hash to be signed or verified via the SignHash and Verify methods. In both cases, the Hash should be set prior to calling SignHash or Verify. This property may also be set via the SetEncodedHash method.

property HexG: WideString readonly

The "G" part of a public or private DSA key returned as a hex-encoded SSH1-format bignum. The "G" is the generator. DSA key params consist of G, P, and Q.

property HexP: WideString readonly

The "P" part of a public or private DSA key returned as a hex-encoded SSH1-format bignum. The "P" is a large prime. DSA key params consist of G, P, and Q.

property HexQ: WideString readonly

The "Q" part of a public or private DSA key returned as a hex-encoded SSH1-format bignum. DSA key params consist of G, P, and Q.

property HexX: WideString readonly

The "X" part of a DSA private key returned as a hex-encoded SSH1-format bignum.

property HexY: WideString readonly

The "Y" part of a DSA public key returned as a hex-encoded SSH1-format bignum. (The "Y" value is also accessible w/ a private key, but the "X" value is not available in a DSA public key.)

property LastBinaryResult: OleVariant readonly

Introduced in version 9.5.0.52

The binary data returned by the last (binary data returning) method called. Only available if Chilkat.Global.KeepBinaryResult is set to 1. This provides a means for obtaining large varbinary results in the SQL Server environment (where limitations exist in getting large amounts of data returned by method calls, but where temp tables can be used for binary properties).

property LastErrorHtml: WideString readonly

Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

property LastErrorText: WideString readonly

Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

property LastErrorXml: WideString readonly

Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

property LastMethodSuccess: Integer

Introduced in version 9.5.0.52

Indicate whether the last method call succeeded or failed. A value of 1 indicates success, a value of 0 indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:

  • Any method that returns a string.
  • Any method returning a Chilkat object, binary bytes, or a date/time.
  • Any method returning a standard boolean status value where success = 1 and failure = 0.
  • Any method returning an integer where failure is defined by a return value less than zero.

Note: Methods that do not fit the above requirements will always set this property equal to 1. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

property LastStringResult: WideString readonly

Introduced in version 9.5.0.52

The string return value of the last (string returning) method called. Only available if Chilkat.Global.KeepStringResult is set to 1. This provides a means for obtaining large string results in the SQL Server environment (where limitations exist in getting long strings returned by method calls, but where temp tables can be used for string properties).

Long Strings Returned by ActiveX Methods in SQL Server

property LastStringResultLen: Integer readonly

Introduced in version 9.5.0.53

The length, in characters, of the string contained in the LastStringResult property.

property Signature: OleVariant

The signature created by calling SignHash. If verifying a signature, this may be set prior to calling the Verify method.

property VerboseLogging: Integer

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.

property Version: WideString readonly

Version of the component/library, such as "9.4.1.42"

Methods

function FromDer(derData: OleVariant): Integer;

Loads a DSA private key from in-memory DSA DER encoded bytes.

Returns 1 for success, 0 for failure.

function FromDerFile(path: WideString): Integer;

Loads a DSA private key from a DER-encoded file.

Returns 1 for success, 0 for failure.

Convert DSA DER Private Key to PEM

function FromEncryptedPem(password: WideString; pemData: WideString): Integer;

Loads a DSA private key from an in-memory encrypted PEM-formatted string. If the PEM passed to this method is unencrypted, the password is ignored and the PEM is simply loaded.

Returns 1 for success, 0 for failure.

function FromPem(pemData: WideString): Integer;

Loads a DSA private key from an in-memory unencrypted PEM-formatted string.

Returns 1 for success, 0 for failure.

DSA Signature Create and Verify

function FromPublicDer(derData: OleVariant): Integer;

Loads a DSA public key from an in-memory DER-encoded byte array.

Returns 1 for success, 0 for failure.

function FromPublicDerFile(path: WideString): Integer;

Loads a DSA public key from a DER-encoded file.

Returns 1 for success, 0 for failure.

function FromPublicPem(pemData: WideString): Integer;

Loads a DSA public-key from an in-memory PEM string.

Returns 1 for success, 0 for failure.

function FromXml(xmlKey: WideString): Integer;

Loads a DSA public or private key from an in-memory XML string.

Returns 1 for success, 0 for failure.

function GenKey(numBits: Integer): Integer;

Generates a new DSA key that is numBits bits in length. The numBits should be at least 1024 bits and a multiple of 64. Typical values are 1024 and 2048. The newly generated key may be exported by calling one of the To* methods.

Returns 1 for success, 0 for failure.

DSA Generate Key

function GenKeyFromParamsDer(derBytes: OleVariant): Integer;

Generates a new DSA key from in-memory DER parameters created by OpenSSL. The newly generated key may be exported by calling one of the To* methods.

Returns 1 for success, 0 for failure.

function GenKeyFromParamsDerFile(path: WideString): Integer;

Generates a new DSA key from a DER-format parameters file created by OpenSSL. An example of using OpenSSL to generate DSA parameters in DER format is:

openssl dsaparam -outform DER 1024 < seedData.xml > dsaparam.der
The newly generated key may be exported by calling one of the To* methods.

Returns 1 for success, 0 for failure.

Generate new DSA Key from OpenSSL Parameters File

function GenKeyFromParamsPem(pem: WideString): Integer;

Generates a new DSA key from parameters (PEM formatted string) created by OpenSSL. The newly generated key may be exported by calling one of the To* methods.

Returns 1 for success, 0 for failure.

function GenKeyFromParamsPemFile(path: WideString): Integer;

Generates a new DSA key from a PEM parameters file created by OpenSSL. The newly generated key may be exported by calling one of the To* methods.

OpenSSL provides the ability to generate DSA key parameters. For example:

openssl dsaparam 1024 < seedData.txt > dsaparam.pem

Here is a sample DSA parameters PEM:

-----BEGIN DSA PARAMETERS-----
MIIBHgKBgQCXIAx4XzLVZ5ZqOFzdsYWVyH/6E/mVPw4TgMZS6Wxajnbdn1/CUBzE
RWTUp8SguTSDpjC1Q/nyno0G6Q96VoW+PUXv8qUph8vbSaEdsjYO/8jSfzkGfvsa
cucr1ythfNyk63aZAKzxeutOmsVe77l6pZI96ROjWF5iizuUB4WgmwIVANxM70wH
8iPPYVzPZqtXCB66I2SnAoGAIbW2VYRjRdoA7trJgmnfWakghKwV1WyaYrotqeDE
07/dipp0cNuY0IAJgSmqLHlAkNa2ZNI/c1mNxcwhYzZrnn8CXIqrYmtI33w0PYCx
KHPqj7puhddFwYS/rFiyWAN0jtCMHlfCVzFGbSzach5QQraPV9YApJXy+ORJ8VPU
/zo=
-----END DSA PARAMETERS-----

Returns 1 for success, 0 for failure.

function GetEncodedHash(encoding: WideString): WideString;

Returns the bytes of the Hash property as a hex or base64 encoded string. The encoding should be set to either "hex" or "base64".

Returns a zero-length WideString on failure

function GetEncodedSignature(encoding: WideString): WideString;

Returns the bytes of the Signature property as a hex or base64 encoded string. The encoding should be set to either "hex" or "base64". The Signature property is set when SignHash is called.

Returns a zero-length WideString on failure

function LoadText(path: WideString): WideString;

Convenience method to load the entire contents of a text file into a string. It is assumed that the text contains ANSI encoded character data.

Returns a zero-length WideString on failure

function SaveText(strToSave: WideString; path: WideString): Integer;

Convenience method to save a string to a text file. The text is saved using the ANSI character encoding.

Returns 1 for success, 0 for failure.

function SetEncodedHash(encoding: WideString; encodedHash: WideString): Integer;

Provides a way to set the Hash property by passing an encoded string. The encoding can be "hex" or "base64". The encodedHash contains the encoded bytes of the hash that will be signed or verified via the SignHash and Verify methods.

Returns 1 for success, 0 for failure.

function SetEncodedSignature(encoding: WideString; encodedSig: WideString): Integer;

Sets the bytes of the Signature property. (The signature must be specified prior to calling the Verify method.) This method allows for the signature to be set via a hex or base64 encoded string. The encoding should be set to either "hex" or "base64".

Returns 1 for success, 0 for failure.

function SetEncodedSignatureRS(encoding: WideString; encodedR: WideString; encodedS: WideString): Integer;

Sets the bytes of the Signature property by providing the R and S values in encoded form. (The signature must be specified prior to calling the Verify method.) The R and S values may be set via a hex or base64 encoded string. The encoding should be set to either "hex" or "base64".

Returns 1 for success, 0 for failure.

function SetKeyExplicit(groupSizeInBytes: Integer; pHex: WideString; qHex: WideString; gHex: WideString; xHex: WideString): Integer;

Sets the DSA object's private key from explicitly provided pHex, qHex, gHex, and xHex values. The groupSizeInBytes specifies the group size (in bytes). It is typically equal to 20, which is the length of the underlying hash function (SHA-1) for signing. The pHex, qHex, gHex, and xHex values are hex-encoded SSH1-format bignums.

Returns 1 for success, 0 for failure.

function SetPubKeyExplicit(groupSizeInBytes: Integer; pHex: WideString; qHex: WideString; gHex: WideString; yHex: WideString): Integer;

Sets the DSA object's private key from explicitly provided pHex, qHex, gHex, and yHex values. The groupSizeInBytes specifies the group size (in bytes). It is typically equal to 20, which is the length of the underlying hash function (SHA-1) for signing. The pHex, qHex, gHex, and yHex values are hex-encoded SSH1-format bignums.

Returns 1 for success, 0 for failure.

function SignHash(): Integer;

Signs a hash using the digital signature algorithm. Before calling this method, set the hash to be signed by either calling SetEncodedHash or by setting the Hash property. If SignHash returns 1, the signature may be retrieved by either calling GetEncodedHash, or by accessing the Signature property.

Returns 1 for success, 0 for failure.

DSA Signature Create and Verify

function ToDer(): OleVariant;

Writes the DSA private key to a DER-encoded byte array.

Returns a zero-length byte array (as an OleVariant) on failure.
An empty array will have a VarArrayHighBound of -1 meaning 0 elements.

function ToDerFile(path: WideString): Integer;

Writes the DSA private key to a DER-format file.

Returns 1 for success, 0 for failure.

DSA Generate Key

function ToEncryptedPem(password: WideString): WideString;

Writes the DSA private key to an in-memory encrypted PEM string.

Returns a zero-length WideString on failure

DSA Generate Key

Convert DSA DER Private Key to PEM

function ToPem(): WideString;

Writes the DSA private key to an in-memory PEM string.

Returns a zero-length WideString on failure

Convert DSA DER Private Key to PEM

function ToPublicDer(): OleVariant;

Writes the DSA public key to a DER-encoded byte array.

Returns a zero-length byte array (as an OleVariant) on failure.
An empty array will have a VarArrayHighBound of -1 meaning 0 elements.

function ToPublicDerFile(path: WideString): Integer;

Writes the DSA public key to a DER-format file.

Returns 1 for success, 0 for failure.

DSA Generate Key

function ToPublicPem(): WideString;

Writes the DSA public key to an in-memory PEM string.

Returns a zero-length WideString on failure

DSA Generate Key

function ToXml(bPublicOnly: Integer): WideString;

Writes the DSA private or public key to an in-memory XML string. The bPublicOnly determines whether the public or private key is written.

Returns a zero-length WideString on failure

DSA Generate Key

function UnlockComponent(unlockCode: WideString): Integer;

Unlocks the component. This must be called once prior to calling any other method.

Returns 1 for success, 0 for failure.

Diagnosing UnlockComponent Problems

UnlockComponent LastErrorText shows exact string passed to it.

Verify UnlockComponent Success w/ Permanent Unlock Code

LastErrorText Standard Information

function Verify(): Integer;

Verifies a DSA signature. The Hash and Signature properties must be set prior to calling this method. (These properties may also be set via the SetEncodedHash and SetEncodedSignature methods.)

Returns 1 for success, 0 for failure.

DSA Signature Create and Verify

function VerifyKey(): Integer;

Verifies that the public or private key contained in the calling Dsa object is valid. Returns 1 if valid, otherwise returns 0.

DSA Signature Create and Verify