Zig

Duplicate Java Verify RSA Signature

See more RSA Examples

Demonstrates how to duplicate a snippet of Java code that verifies an RSA signature. Zig

const std = @import("std");
const chilkat = @import("chilkat");

pub fn main(init: std.process.Init) !void {
    const alloc = init.arena.allocator();

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

    // This example duplicates the following Java code:

    // import com.sun.org.apache.xml.internal.security.utils.Base64;
    // import java.io.ByteArrayInputStream;
    // import java.security.PublicKey;
    // import java.security.Signature;
    // import java.security.cert.CertificateFactory;
    // import java.security.cert.X509Certificate;
    // public class validateSazetak {
    //   public static void main(String[] args) {
    //   String signatureAlgorithm = "SHA256withRSA";
    //   String base64DataToBeSigned = "Hlp...LE4=";
    //   String base64Certificate = "MII...TlQ==";
    //   String base64Signature = "I00...pZA==";
    //   try {
    //       CertificateFactory cf;
    //       X509Certificate certificate = null;
    //       cf = CertificateFactory.getInstance("X.509");
    //       certificate = (X509Certificate) cf.generateCertificate(new
    //       ByteArrayInputStream(Base64.decode(base64Certificate)));
    //
    //       Signature signature = Signature.getInstance(signatureAlgorithm, "SunRsaSign");
    //       PublicKey pk = (PublicKey) certificate.getPublicKey();
    //       signature.initVerify(pk);
    //
    //       byte[] hashBytes = Base64.decode(base64DataToBeSigned);
    //       signature.update(hashBytes);
    //
    //       byte[] sigBytes = Base64.decode(base64Signature);
    //       boolean validity = signature.verify(sigBytes);
    //       System.out.println("Is valid signature:" + validity);
    //     } catch (Exception e) {
    //         System.out.println(e);
    //     }
    // }

    const base64_data_to_be_signed = "Hlp...LE4=";
    const base64_certificate = "MII...TlQ==";
    const base64_signature = "I00...pZA==";

    const cert = try chilkat.Cert.init();
    defer cert.deinit();
    cert.loadFromBase64(base64_certificate) catch {
        std.debug.print("{s}\n", .{try cert.getLastErrorText(alloc)});
        return;
    };

    const rsa = try chilkat.Rsa.init();
    defer rsa.deinit();

    rsa.setX509Cert(cert, false) catch {
        std.debug.print("{s}\n", .{try rsa.getLastErrorText(alloc)});
        return;
    };

    rsa.setEncodingMode("base64");
    rsa.verifyStringENC(base64_data_to_be_signed, "sha256", base64_signature) catch {
        std.debug.print("{s}\n", .{try rsa.getLastErrorText(alloc)});
        return;
    };

    std.debug.print("Signature verified.\n", .{});
}