Chilkat Examples

ChilkatHOMEAndroid™Classic ASPCC++C#Mono C#.NET Core C#C# UWP/WinRTDataFlexDelphi ActiveXDelphi DLLVisual FoxProJavaLianjaMFCObjective-CPerlPHP ActiveXPHP ExtensionPowerBuilderPowerShellPureBasicCkPythonChilkat2-PythonRubySQL ServerSwift 2Swift 3,4,5...TclUnicode CUnicode C++Visual Basic 6.0VB.NETVB.NET UWP/WinRTVBScriptXojo PluginNode.jsExcelGo

C# UWP/WinRT Examples

Web API Categories

ASN.1
Amazon EC2
Amazon Glacier
Amazon S3
Amazon S3 (new)
Amazon SES
Amazon SNS
Amazon SQS
Azure Cloud Storage
Azure Service Bus
Azure Table Service
Base64
Bounced Email
Box
CAdES
CSR
CSV
Certificates
Compression
DKIM / DomainKey
DSA
Diffie-Hellman
Digital Signatures
Dropbox
Dynamics CRM
EBICS
ECC
Ed25519
Email Object
Encryption
FTP
FileAccess
Firebase
GMail REST API
GMail SMTP/IMAP/POP
Geolocation
Google APIs
Google Calendar
Google Cloud SQL
Google Cloud Storage
Google Drive
Google Photos
Google Sheets
Google Tasks
Gzip
HTML-to-XML/Text
HTTP

HTTP Misc
IMAP
JSON
JSON Web Encryption (JWE)
JSON Web Signatures (JWS)
JSON Web Token (JWT)
Java KeyStore (JKS)
MHT / HTML Email
MIME
MS Storage Providers
Microsoft Graph
NTLM
OAuth1
OAuth2
OIDC
Office365
OneDrive
OpenSSL
Outlook
Outlook Calendar
Outlook Contact
PDF Signatures
PEM
PFX/P12
PKCS11
POP3
PRNG
REST
REST Misc
RSA
SCP
SCard
SFTP
SMTP
SSH
SSH Key
SSH Tunnel
ScMinidriver
SharePoint
Socket/SSL/TLS
Spider
Stream
Tar Archive
Upload
WebSocket
XAdES
XML
XML Digital Signatures
XMP
Zip
curl

 

 

 

(C# UWP/WinRT) DSA R,S Signature Values

See more DSA Examples

Creates a DSA signature. Gets r,s values from the signature. Re-creates the DSA signature ASN.1 from the r,s values. Then verifies the signature using the re-created ASN.1 DSA signature.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads

Chilkat for the Universal Windows Platform (UWP)

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Crypt2 crypt = new Chilkat.Crypt2();

crypt.EncodingMode = "hex";
crypt.HashAlgorithm = "sha-1";

string hashStr = await crypt.HashFileENCAsync("qa_data/hamlet.xml");
Debug.WriteLine("hash to sign: " + hashStr);

Chilkat.Dsa dsa = new Chilkat.Dsa();

string pemPrivateKey;
pemPrivateKey = dsa.LoadText("qa_data/dsa/dsaPrivKey2.pem");
bool success = dsa.FromPem(pemPrivateKey);
if (success == false) {
    Debug.WriteLine(dsa.LastErrorText);
    return;
}

// Load the hash to be signed into the DSA object:
success = dsa.SetEncodedHash("hex",hashStr);
if (success == false) {
    Debug.WriteLine(dsa.LastErrorText);
    return;
}

// Sign the hash.
success = dsa.SignHash();
if (success == false) {
    Debug.WriteLine(dsa.LastErrorText);
    return;
}

// Get the ASN.1 signature.
string asnSig = dsa.GetEncodedSignature("base64");
Debug.WriteLine("Signature: " + asnSig);

// Examine the details of the ASN.1 signature.
// We want to get the r,s values as hex strings..
Chilkat.Asn asn = new Chilkat.Asn();
success = asn.LoadEncoded(asnSig,"base64");
if (success == false) {
    Debug.WriteLine(asn.LastErrorText);
    return;
}

// Get the ASN.1 as XML.
Chilkat.Xml xml = new Chilkat.Xml();
success = xml.LoadXml(asn.AsnToXml());
Debug.WriteLine("Signature as XML: ");
Debug.WriteLine(xml.GetXml());

// Sample XML shown here.
// The r and s values are the two hex strings in the XML.

// <?xml version="1.0" encoding="utf-8"?>
// <sequence>
//     <int>2C187F3AB6E47A66497B86CE97BB39E2133810F5</int>
//     <int>588E53D3F7B69636B48FD7175E99A3961BD7D775</int>
// </sequence>

// Pretend we're starting with r,s
string r = "2C187F3AB6E47A66497B86CE97BB39E2133810F5";
string s = "588E53D3F7B69636B48FD7175E99A3961BD7D775";

// Build the XML that will be converted to ASN.1
xml.Clear();
xml.Tag = "sequence";
xml.NewChild2("int",r);
xml.NewChild2("int",s);

// Convert the XML to ASN.1
success = asn.LoadAsnXml(xml.GetXml());

// Emit the signature as DER encoded ASN.1 (base64)
asnSig = asn.GetEncodedDer("base64");

// --------------------------------------------------------------------
// Verify the signature using the asnSig we built from the r,s values
// --------------------------------------------------------------------

Chilkat.Dsa dsa2 = new Chilkat.Dsa();

// Load the DSA public key to be used for verification:
string pemPublicKey;
pemPublicKey = dsa2.LoadText("qa_data/dsa/dsaPubKey2.pem");
success = dsa2.FromPublicPem(pemPublicKey);
if (success == false) {
    Debug.WriteLine(dsa2.LastErrorText);
    return;
}

// Load the hash to be verified.
success = dsa2.SetEncodedHash("hex",hashStr);
if (success == false) {
    Debug.WriteLine(dsa2.LastErrorText);
    return;
}

// Load the ASN.1 signature:
success = dsa2.SetEncodedSignature("base64",asnSig);
if (success == false) {
    Debug.WriteLine(dsa2.LastErrorText);
    return;
}

// Verify:
success = dsa2.Verify();
if (success == false) {
    Debug.WriteLine(dsa2.LastErrorText);
}
else {
    Debug.WriteLine("DSA Signature Verified!");
}


 

© 2000-2022 Chilkat Software, Inc. All Rights Reserved.