Dsa Tcl Reference Documentation

Dsa

Current Version: 10.1.2

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).

Object Creation

set myDsa [new CkDsa]

Properties

DebugLogFilePath
string
# ckStr is a CkString
CkDsa_get_DebugLogFilePath $myDsa $ckStr
set strVal [CkDsa_get_debugLogFilePath $myDsa]
CkDsa_put_DebugLogFilePath $myDsa $strVal

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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GroupSize
integer
set intVal [CkDsa_get_GroupSize $myDsa]
CkDsa_put_GroupSize $myDsa $intVal

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.

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Hash

# ckBytes is a CkByteData
CkDsa_get_Hash $myDsa $ckBytes
CkDsa_put_Hash $myDsa $ckBytes

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.

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HexG
string
# ckStr is a CkString
CkDsa_get_HexG $myDsa $ckStr
set strVal [CkDsa_get_hexG $myDsa]

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.

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HexP
string
# ckStr is a CkString
CkDsa_get_HexP $myDsa $ckStr
set strVal [CkDsa_get_hexP $myDsa]

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.

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HexQ
string
# ckStr is a CkString
CkDsa_get_HexQ $myDsa $ckStr
set strVal [CkDsa_get_hexQ $myDsa]

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.

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HexX
string
# ckStr is a CkString
CkDsa_get_HexX $myDsa $ckStr
set strVal [CkDsa_get_hexX $myDsa]

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

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HexY
string
# ckStr is a CkString
CkDsa_get_HexY $myDsa $ckStr
set strVal [CkDsa_get_hexY $myDsa]

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.)

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LastErrorHtml
string
# ckStr is a CkString
CkDsa_get_LastErrorHtml $myDsa $ckStr
set strVal [CkDsa_get_lastErrorHtml $myDsa]

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
string
# ckStr is a CkString
CkDsa_get_LastErrorText $myDsa $ckStr
set strVal [CkDsa_get_lastErrorText $myDsa]

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
string
# ckStr is a CkString
CkDsa_get_LastErrorXml $myDsa $ckStr
set strVal [CkDsa_get_lastErrorXml $myDsa]

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
boolean 1/0
set boolVal [CkDsa_get_LastMethodSuccess $myDsa]
CkDsa_put_LastMethodSuccess $myDsa $boolVal

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.

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Signature

# ckBytes is a CkByteData
CkDsa_get_Signature $myDsa $ckBytes
CkDsa_put_Signature $myDsa $ckBytes

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

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UncommonOptions
string
# ckStr is a CkString
CkDsa_get_UncommonOptions $myDsa $ckStr
set strVal [CkDsa_get_uncommonOptions $myDsa]
CkDsa_put_UncommonOptions $myDsa $strVal
Introduced in version 9.5.0.90

This is a catch-all property to be used for uncommon needs. This property defaults to the empty string and should typically remain empty.

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Utf8
boolean 1/0
set boolVal [CkDsa_get_Utf8 $myDsa]
CkDsa_put_Utf8 $myDsa $boolVal

When set to 1, all "const char *" arguments are interpreted as utf-8 strings. If set to 0 (the default), then "const char *" arguments are interpreted as ANSI strings. Also, when set to 1, and Chilkat method returning a "const char *" is returning the utf-8 representation. If set to 0, all "const char *" return values are ANSI strings.

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VerboseLogging
boolean 1/0
set boolVal [CkDsa_get_VerboseLogging $myDsa]
CkDsa_put_VerboseLogging $myDsa $boolVal

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.

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Version
string
# ckStr is a CkString
CkDsa_get_Version $myDsa $ckStr
set strVal [CkDsa_get_version $myDsa]

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

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Methods

FromDer
# derData is a CkByteData
set status [CkDsa_FromDer $derData]

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

Returns 1 for success, 0 for failure.

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FromDerFile
# path is a string
set status [CkDsa_FromDerFile $path]

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

Returns 1 for success, 0 for failure.

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FromEncryptedPem
# password is a string
# pemData is a string
set status [CkDsa_FromEncryptedPem $password $pemData]

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.

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FromPem
# pemData is a string
set status [CkDsa_FromPem $pemData]

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

Returns 1 for success, 0 for failure.

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FromPublicDer
# derData is a CkByteData
set status [CkDsa_FromPublicDer $derData]

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

Returns 1 for success, 0 for failure.

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FromPublicDerFile
# path is a string
set status [CkDsa_FromPublicDerFile $path]

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

Returns 1 for success, 0 for failure.

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FromPublicPem
# pemData is a string
set status [CkDsa_FromPublicPem $pemData]

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

Returns 1 for success, 0 for failure.

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FromXml
# xmlKey is a string
set status [CkDsa_FromXml $xmlKey]

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

Returns 1 for success, 0 for failure.

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GenKey
# numBits is an integer
set status [CkDsa_GenKey $numBits]

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.

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GenKey2
# keyLenBits is an integer
# modLenBits is an integer
set status [CkDsa_GenKey2 $keyLenBits $modLenBits]
Introduced in version 9.5.0.90

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 1 for success, 0 for failure.

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GenKeyFromParamsDer
# derBytes is a CkByteData
set status [CkDsa_GenKeyFromParamsDer $derBytes]

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.

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GenKeyFromParamsDerFile
# path is a string
set status [CkDsa_GenKeyFromParamsDerFile $path]

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.

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GenKeyFromParamsPem
# pem is a string
set status [CkDsa_GenKeyFromParamsPem $pem]

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.

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GenKeyFromParamsPemFile
# path is a string
set status [CkDsa_GenKeyFromParamsPemFile $path]

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.

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GenKeyFromPQG
# pHex is a string
# qHex is a string
# gHex is a string
set status [CkDsa_GenKeyFromPQG $pHex $qHex $gHex]
Introduced in version 9.5.0.90

Generates a new DSA key from pre-chosen P, Q, and G params.

Returns 1 for success, 0 for failure.

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GetEncodedHash
# encoding is a string
# outStr is a CkString (output)
set status [CkDsa_GetEncodedHash $encoding $outStr]
set retStr [CkDsa_getEncodedHash $myDsa $encoding]

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 1 for success, 0 for failure.

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GetEncodedSignature
# encoding is a string
# outStr is a CkString (output)
set status [CkDsa_GetEncodedSignature $encoding $outStr]
set retStr [CkDsa_getEncodedSignature $myDsa $encoding]

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 1 for success, 0 for failure.

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LoadText
# path is a string
# outStr is a CkString (output)
set status [CkDsa_LoadText $path $outStr]
set retStr [CkDsa_loadText $myDsa $path]

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 1 for success, 0 for failure.

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SaveText
# strToSave is a string
# path is a string
set status [CkDsa_SaveText $strToSave $path]

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.

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SetEncodedHash
# encoding is a string
# encodedHash is a string
set status [CkDsa_SetEncodedHash $encoding $encodedHash]

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.

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SetEncodedSignature
# encoding is a string
# encodedSig is a string
set status [CkDsa_SetEncodedSignature $encoding $encodedSig]

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.

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SetEncodedSignatureRS
# encoding is a string
# encodedR is a string
# encodedS is a string
set status [CkDsa_SetEncodedSignatureRS $encoding $encodedR $encodedS]

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.

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SetKeyExplicit
# groupSizeInBytes is an integer
# pHex is a string
# qHex is a string
# gHex is a string
# xHex is a string
set status [CkDsa_SetKeyExplicit $groupSizeInBytes $pHex $qHex $gHex $xHex]

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.

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SetPubKeyExplicit
# groupSizeInBytes is an integer
# pHex is a string
# qHex is a string
# gHex is a string
# yHex is a string
set status [CkDsa_SetPubKeyExplicit $groupSizeInBytes $pHex $qHex $gHex $yHex]

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.

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SignHash
set status [CkDsa_SignHash]

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.

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ToDer
# outBytes is a CkByteData (output)
set status [CkDsa_ToDer $outData]

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

Returns 1 for success, 0 for failure.

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ToDerFile
# path is a string
set status [CkDsa_ToDerFile $path]

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

Returns 1 for success, 0 for failure.

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ToEncryptedPem
# password is a string
# outStr is a CkString (output)
set status [CkDsa_ToEncryptedPem $password $outStr]
set retStr [CkDsa_toEncryptedPem $myDsa $password]

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

Returns 1 for success, 0 for failure.

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ToPem
# outStr is a CkString (output)
set status [CkDsa_ToPem $outStr]
set retStr [CkDsa_toPem $myDsa]

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

Returns 1 for success, 0 for failure.

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ToPublicDer
# outBytes is a CkByteData (output)
set status [CkDsa_ToPublicDer $outData]

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

Returns 1 for success, 0 for failure.

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ToPublicDerFile
# path is a string
set status [CkDsa_ToPublicDerFile $path]

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

Returns 1 for success, 0 for failure.

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ToPublicPem
# outStr is a CkString (output)
set status [CkDsa_ToPublicPem $outStr]
set retStr [CkDsa_toPublicPem $myDsa]

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

Returns 1 for success, 0 for failure.

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ToXml
# bPublicOnly is a boolean
# outStr is a CkString (output)
set status [CkDsa_ToXml $bPublicOnly $outStr]
set retStr [CkDsa_toXml $myDsa $bPublicOnly]

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 1 for success, 0 for failure.

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Verify
set status [CkDsa_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 1 for success, 0 for failure.

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VerifyKey
set retBool [CkDsa_VerifyKey]

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

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