feat: Implement way of retrieving CAs in signing process

src/main/java/de/mlessmann/certassist/openssl/CertificateProvider.java

@@ -0,0 +1,11 @@
+package de.mlessmann.certassist.openssl;
+
+/**
+ * Accessor interface to the certificate storage.
+ */
+public interface CertificateProvider {
+    /**
+     * A stored certificate is needed (e.g. for command line operations when signing sub certificates).
+     */
+    CertificateUsage requestCertificateUsage(String fingerprint);
+}

src/main/java/de/mlessmann/certassist/openssl/CertificateUsage.java

@@ -0,0 +1,17 @@
+package de.mlessmann.certassist.openssl;
+
+import java.nio.file.Path;
+
+/**
+ * Instance of a certificate that is temporarily stored on disk to be available for use in command line calls.
+ * The instance implements AutoCloseable to enable cleanup after the stored files are no longer needed.
+ * @implSpec The files should be removed from disk when the instance is closed, UNLESS the provided paths are the permanent storage location for the certificate files.
+ */
+public interface CertificateUsage extends AutoCloseable {
+    Path certificatePath();
+    Path certificateKeyPath();
+    String fingerprint();
+
+    @Override
+    void close();
+}

src/main/java/de/mlessmann/certassist/openssl/OpenSSLCertificateCreator.java

@@ -47,6 +47,7 @@ public class OpenSSLCertificateCreator {
 
     private final ExecutableResolver executableResolver;
     private final CertPasswordProvider passwordProvider;
+    private final CertificateProvider certificateProvider;
 
     private static String buildSubjectArg(CertificateRequest request) {
         String certSubject = OPENSSL_CERT_SUBJECT_TEMPLATE
@@ -77,21 +78,23 @@ public class OpenSSLCertificateCreator {
         }
 
         String certPassword = passwordProvider.generateNewPassword();
-        Path keyFile = createKeyfile(request, tmpDir.resolve("root.key"), certPassword);
+        Path keyFile = createKeyfile(request, tmpDir.resolve("certificate.key"), certPassword);
-        Path rootCert = createCertificate(request, keyFile, tmpDir.resolve("root.crt"), certPassword);
         if (
             request.getType() == RequestType.ROOT_AUTHORITY || request.getType() == RequestType.STANDALONE_CERTIFICATE
         ) {
-            String fingerprint = getCertificateFingerprint(rootCert);
+            Path certificate = createCertificate(request, keyFile, tmpDir.resolve("certificate.crt"), certPassword);
-            return new OpenSSLCertificateResult(tmpDir, rootCert, keyFile, fingerprint);
+            String fingerprint = getCertificateFingerprint(certificate);
+            passwordProvider.setPasswordFor(fingerprint, certPassword);
+            return new OpenSSLCertificateResult(tmpDir, certificate, keyFile, fingerprint);
         }
 
-        Path childKey = createKeyfile(request, tmpDir.resolve("child.key"), certPassword);
+        try (var certAuthority = certificateProvider.requestCertificateUsage(request.getTrustingAuthority())) {
-        Path unsignedCert = createSigningRequest(request, childKey, tmpDir.resolve("child.csr"), certPassword);
+            Path unsignedCert = createSigningRequest(request, keyFile, tmpDir.resolve("child.csr"), certPassword);
-        Path signedCert = signCertificate(request, rootCert, keyFile, unsignedCert, certPassword);
+            Path signedCert = signCertificate(request, certAuthority.certificatePath(), certAuthority.certificateKeyPath(), unsignedCert, certPassword);
-        String fingerPrint = getCertificateFingerprint(signedCert);
+            String fingerprint = getCertificateFingerprint(signedCert);
-        passwordProvider.setPasswordFor(fingerPrint, certPassword);
+            passwordProvider.setPasswordFor(fingerprint, certPassword);
-        return new OpenSSLCertificateResult(tmpDir, signedCert, childKey, fingerPrint);
+            return new OpenSSLCertificateResult(tmpDir, signedCert, keyFile, fingerprint);
+        }
     }
 
     private Path createKeyfile(CertificateRequest request, Path outFile, String filePassword)

src/test/java/de/mlessmann/certassist/TestOpenSSLCertificateCreator.java

@@ -11,19 +11,24 @@ import org.junit.jupiter.api.Test;
 
 class TestOpenSSLCertificateCreator {
 
-    private OpenSSLCertificateCreator openSSLCertificateCreator;
+    private CertPasswordProvider passwordProvider;
 
     @BeforeEach
     void setUp() {
-        CertPasswordProvider passwordProvider = mock(CertPasswordProvider.class);
+        passwordProvider = mock(CertPasswordProvider.class);
         when(passwordProvider.generateNewPassword()).thenReturn("ABC-123");
-
-        ExecutableResolver executableResolver = new ExecutableResolver();
-        openSSLCertificateCreator = new OpenSSLCertificateCreator(executableResolver, passwordProvider);
     }
 
     @Test
     void testCertificateCreation() throws Exception {
+        CertificateProvider certificateProvider = mock(CertificateProvider.class);
+        ExecutableResolver executableResolver = new ExecutableResolver();
+        var certificateCreator = new OpenSSLCertificateCreator(
+            executableResolver,
+            passwordProvider,
+            certificateProvider
+        );
+
         CertificateRequest certRequest = CertificateRequest
             .builder()
             .commonName("test.home")
@@ -32,8 +37,8 @@ class TestOpenSSLCertificateCreator {
             .extension(CertificateRequestExtension.builder().alternativeNames("test2.home", "test3.home"))
             .build();
 
-        try (var cert = openSSLCertificateCreator.createCertificate(certRequest)) {
+        try (var cert = certificateCreator.createCertificate(certRequest)) {
-            assertThat(openSSLCertificateCreator.verifyCertificate(cert.getCertificatePath())).isEqualTo(true);
+            assertThat(certificateCreator.verifyCertificate(cert.getCertificatePath())).isEqualTo(true);
             System.out.println("Certificate created: " + cert);
         }
     }