Zig

Apple Keychain - Create RSA Signature

See more Apple Keychain Examples

Using an RSA private key stored in the Apple Keychain, create a signature by signing the SHA-256 hash of the provided string, then return the signature encoded in Base64 format.

Note: This example requires Chilkat v10.0.0 or greater.

Zig

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

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

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

    const cert = try chilkat.Cert.init();
    defer cert.deinit();

    // On MacOS and iOS, the LoadByCommonName function will search the Apple Keychain for the matching certificate.

    // A digital certificate's Common Name (CN) is a field in the certificate that specifies the name of the entity the
    // certificate is issued to. It is often used to identify the domain name, hostname, or organization the certificate represents.

    // For example:
    // - In an SSL/TLS certificate for a website, the CN typically contains the domain name (e.g., "www.example.com").
    // - For certificates representing individuals or organizations, the CN might include the person's name or the organization's name.

    // The CN is part of the certificate's Subject field and is crucial for verifying that the certificate corresponds
    // to the intended entity, especially in SSL/TLS communications.

    cert.loadByCommonName("Example, Inc.") catch {
        std.debug.print("{s}\n", .{try cert.getLastErrorText(alloc)});
        return;
    };

    const rsa = try chilkat.Rsa.init();
    defer rsa.deinit();
    rsa.setX509Cert(cert, true) catch {
        std.debug.print("{s}\n", .{try rsa.getLastErrorText(alloc)});
        return;
    };

    // Generate an RSA signature by signing the SHA-256 hash of the provided string,
    // then return the signature encoded in Base64 format.
    rsa.setEncodingMode("base64");
    const sig_base64 = rsa.signStringENC(alloc, "to be signed", "sha256") catch {
        std.debug.print("{s}\n", .{try rsa.getLastErrorText(alloc)});
        return;
    };

    std.debug.print("RSA Signature:\n", .{});
    std.debug.print("{s}\n", .{sig_base64});
}