Dsa Delphi DLL Reference Documentation
Dsa
Current Version: 10.1.0
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).
Create/Dispose
var myObject: HCkDsa; begin myObject := CkDsa_Create(); // ... CkDsa_Dispose(myObject); end;
Creates an instance of the HCkDsa object and returns a handle (i.e. a Pointer). The handle is passed in the 1st argument for the functions listed on this page.
Objects created by calling CkDsa_Create must be freed by calling this method. A memory leak occurs if a handle is not disposed by calling this function.
Properties
DebugLogFilePath
procedure CkDsa_putDebugLogFilePath(objHandle: HCkDsa; newPropVal: PWideChar); stdcall;
function CkDsa__debugLogFilePath(objHandle: HCkDsa): PWideChar; stdcall;
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:
- a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
- the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
- there is an internal problem (bug) in the Chilkat code that causes the hang.
See the notes about PWideChar memory ownership and validity.
GroupSize
procedure CkDsa_putGroupSize(objHandle: HCkDsa; newPropVal: Integer); stdcall;
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.
topHash
procedure CkDsa_putHash(objHandle: HCkDsa; newPropVal: HCkByteData); stdcall;
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.
topHexG
function CkDsa__hexG(objHandle: HCkDsa): PWideChar; stdcall;
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.
See the notes about PWideChar memory ownership and validity.
topHexP
function CkDsa__hexP(objHandle: HCkDsa): PWideChar; stdcall;
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.
See the notes about PWideChar memory ownership and validity.
topHexQ
function CkDsa__hexQ(objHandle: HCkDsa): PWideChar; stdcall;
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.
See the notes about PWideChar memory ownership and validity.
topHexX
function CkDsa__hexX(objHandle: HCkDsa): PWideChar; stdcall;
The "X" part of a DSA private key returned as a hex-encoded SSH1-format bignum.
See the notes about PWideChar memory ownership and validity.
topHexY
function CkDsa__hexY(objHandle: HCkDsa): PWideChar; stdcall;
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.)
See the notes about PWideChar memory ownership and validity.
topLastErrorHtml
function CkDsa__lastErrorHtml(objHandle: HCkDsa): PWideChar; stdcall;
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.
See the notes about PWideChar memory ownership and validity.
topLastErrorText
function CkDsa__lastErrorText(objHandle: HCkDsa): PWideChar; stdcall;
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.
See the notes about PWideChar memory ownership and validity.
LastErrorXml
function CkDsa__lastErrorXml(objHandle: HCkDsa): PWideChar; stdcall;
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.
See the notes about PWideChar memory ownership and validity.
topLastMethodSuccess
procedure CkDsa_putLastMethodSuccess(objHandle: HCkDsa; newPropVal: wordbool); stdcall;
Indicate whether the last method call succeeded or failed. A value of True indicates success, a value of False 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 = True and failure = False.
- 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 True. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.
topSignature
procedure CkDsa_putSignature(objHandle: HCkDsa; newPropVal: HCkByteData); stdcall;
The signature created by calling SignHash. If verifying a signature, this may be set prior to calling the Verify method.
topUncommonOptions
procedure CkDsa_putUncommonOptions(objHandle: HCkDsa; newPropVal: PWideChar); stdcall;
function CkDsa__uncommonOptions(objHandle: HCkDsa): PWideChar; stdcall;
This is a catch-all property to be used for uncommon needs. This property defaults to the empty string and should typically remain empty.
See the notes about PWideChar memory ownership and validity.
topVerboseLogging
procedure CkDsa_putVerboseLogging(objHandle: HCkDsa; newPropVal: wordbool); stdcall;
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.
topVersion
function CkDsa__version(objHandle: HCkDsa): PWideChar; stdcall;
Version of the component/library, such as "9.5.0.94"
See the notes about PWideChar memory ownership and validity.
Methods
FromDer
Loads a DSA private key from in-memory DSA DER-encoded bytes.
Returns True for success, False for failure.
topFromDerFile
path: PWideChar): wordbool; stdcall;
Loads a DSA private key from a DER-encoded file.
Returns True for success, False for failure.
FromEncryptedPem
password: PWideChar;
pemData: PWideChar): wordbool; stdcall;
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 True for success, False for failure.
topFromPem
pemData: PWideChar): wordbool; stdcall;
Loads a DSA private key from an in-memory unencrypted PEM-formatted string.
Returns True for success, False for failure.
FromPublicDer
Loads a DSA public key from an in-memory DER-encoded byte array.
Returns True for success, False for failure.
topFromPublicDerFile
path: PWideChar): wordbool; stdcall;
FromPublicPem
pemData: PWideChar): wordbool; stdcall;
Loads a DSA public-key from an in-memory PEM string.
Returns True for success, False for failure.
topFromXml
xmlKey: PWideChar): wordbool; stdcall;
Loads a DSA public or private key from an in-memory XML string.
Returns True for success, False for failure.
topGenKey
numBits: Integer): wordbool; stdcall;
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 True for success, False for failure.
GenKey2
keyLenBits: Integer;
modLenBits: Integer): wordbool; stdcall;
Generates a new DSA key that is keyLenBits bits in length with a modulus of size modLenBits bits. The keyLenBits should be at least 1024 bits and a multiple of 64. FIPS 186-4 specifies the key length (bits) and modulus size (bits) to have one of the values: (1024, 160), (2048, 224), (2048, 256), or (3072, 256).
Returns True for success, False for failure.
topGenKeyFromParamsDer
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 True for success, False for failure.
topGenKeyFromParamsDerFile
path: PWideChar): wordbool; stdcall;
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.derThe newly generated key may be exported by calling one of the To* methods.
Returns True for success, False for failure.
GenKeyFromParamsPem
pem: PWideChar): wordbool; stdcall;
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 True for success, False for failure.
topGenKeyFromParamsPemFile
path: PWideChar): wordbool; stdcall;
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 True for success, False for failure.
topGenKeyFromPQG
pHex: PWideChar;
qHex: PWideChar;
gHex: PWideChar): wordbool; stdcall;
Generates a new DSA key from pre-chosen P, Q, and G params.
Returns True for success, False for failure.
topGetEncodedHash
encoding: PWideChar;
outStr: HCkString): wordbool; stdcall;
function CkDsa__getEncodedHash(objHandle: HCkDsa;
encoding: PWideChar): PWideChar; stdcall;
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 True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
topGetEncodedSignature
encoding: PWideChar;
outStr: HCkString): wordbool; stdcall;
function CkDsa__getEncodedSignature(objHandle: HCkDsa;
encoding: PWideChar): PWideChar; stdcall;
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 True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
topLoadText
path: PWideChar;
outStr: HCkString): wordbool; stdcall;
function CkDsa__loadText(objHandle: HCkDsa;
path: PWideChar): PWideChar; stdcall;
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 True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
topSaveText
strToSave: PWideChar;
path: PWideChar): wordbool; stdcall;
Convenience method to save a string to a text file. The text is saved using the ANSI character encoding.
Returns True for success, False for failure.
topSetEncodedHash
encoding: PWideChar;
encodedHash: PWideChar): wordbool; stdcall;
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 True for success, False for failure.
topSetEncodedSignature
encoding: PWideChar;
encodedSig: PWideChar): wordbool; stdcall;
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 True for success, False for failure.
topSetEncodedSignatureRS
encoding: PWideChar;
encodedR: PWideChar;
encodedS: PWideChar): wordbool; stdcall;
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 True for success, False for failure.
topSetKeyExplicit
groupSizeInBytes: Integer;
pHex: PWideChar;
qHex: PWideChar;
gHex: PWideChar;
xHex: PWideChar): wordbool; stdcall;
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 True for success, False for failure.
topSetPubKeyExplicit
groupSizeInBytes: Integer;
pHex: PWideChar;
qHex: PWideChar;
gHex: PWideChar;
yHex: PWideChar): wordbool; stdcall;
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 True for success, False for failure.
topSignHash
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 True, the signature may be retrieved by either calling GetEncodedHash, or by accessing the Signature property.
Returns True for success, False for failure.
ToDer
Writes the DSA private key to a DER-encoded byte array.
Returns True for success, False for failure.
topToDerFile
path: PWideChar): wordbool; stdcall;
Writes the DSA private key to a DER-format file.
Returns True for success, False for failure.
ToEncryptedPem
password: PWideChar;
outStr: HCkString): wordbool; stdcall;
function CkDsa__toEncryptedPem(objHandle: HCkDsa;
password: PWideChar): PWideChar; stdcall;
Writes the DSA private key to an in-memory encrypted PEM string.
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
ToPem
outStr: HCkString): wordbool; stdcall;
function CkDsa__toPem(objHandle: HCkDsa): PWideChar; stdcall;
Writes the DSA private key to an in-memory PEM string.
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
ToPublicDer
Writes the DSA public key to a DER-encoded byte array.
Returns True for success, False for failure.
topToPublicDerFile
path: PWideChar): wordbool; stdcall;
Writes the DSA public key to a DER-format file.
Returns True for success, False for failure.
ToPublicPem
outStr: HCkString): wordbool; stdcall;
function CkDsa__toPublicPem(objHandle: HCkDsa): PWideChar; stdcall;
Writes the DSA public key to an in-memory PEM string.
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
ToXml
bPublicOnly: wordbool;
outStr: HCkString): wordbool; stdcall;
function CkDsa__toXml(objHandle: HCkDsa;
bPublicOnly: wordbool): PWideChar; stdcall;
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 True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
Verify
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 True for success, False for failure.
VerifyKey
Verifies that the public or private key contained in the calling Dsa object is valid. Returns True if valid, otherwise returns False.