Add ML-DSA test coverage for X509_REQ_sign

Author: kojo1

tests/api/test_x509.c

@@ -1061,3 +1061,67 @@ int test_x509_ReqCertFromX509_skid_boundary(void)
 #endif
     return EXPECT_RESULT();
 }
+
+/* Sign a certificate request with an ML-DSA key through the compat layer
+ * (wolfSSL_X509_REQ_sign), round-trip it through DER and verify the
+ * signature with the public key recovered from the parsed request. The
+ * REQ path sizes its DER buffer with WC_DECLARE_VAR/WC_MAX_X509_GEN,
+ * separately from wolfSSL_X509_sign, so it needs its own coverage. */
+int test_x509_REQ_sign_mldsa(void)
+{
+    EXPECT_DECLS;
+#if defined(WOLFSSL_CERT_REQ) && defined(WOLFSSL_CERT_GEN) && \
+    (defined(OPENSSL_EXTRA) || defined(OPENSSL_ALL)) && \
+    defined(WOLFSSL_HAVE_MLDSA) && defined(WOLFSSL_MLDSA_PRIVATE_KEY) && \
+    defined(WOLFSSL_MLDSA_PUBLIC_KEY) && !defined(WOLFSSL_MLDSA_NO_ASN1) && \
+    !defined(WOLFSSL_MLDSA_NO_SIGN) && !defined(WOLFSSL_MLDSA_NO_VERIFY) && \
+    defined(WC_ENABLE_ASYM_KEY_EXPORT) && !defined(NO_FILESYSTEM) && \
+    !defined(NO_BIO) && !defined(NO_PWDBASED) && !defined(WOLFSSL_NO_ML_DSA_44)
+
+    WOLFSSL_BIO*       bio    = NULL;
+    WOLFSSL_EVP_PKEY*  pkey   = NULL;
+    WOLFSSL_EVP_PKEY*  pubkey = NULL;
+    WOLFSSL_X509*      req    = NULL;
+    WOLFSSL_X509*      parsed = NULL;
+    WOLFSSL_X509_NAME* name   = NULL;
+    unsigned char*     der    = NULL;
+    int                derSz  = 0;
+
+    ExpectNotNull(bio = wolfSSL_BIO_new_file(
+        "./certs/mldsa/mldsa44-key.pem", "rb"));
+    ExpectNotNull(pkey = wolfSSL_PEM_read_bio_PrivateKey(bio, NULL, NULL,
+        NULL));
+    wolfSSL_BIO_free(bio);
+    bio = NULL;
+
+    ExpectNotNull(req = wolfSSL_X509_REQ_new());
+    ExpectNotNull(name = wolfSSL_X509_NAME_new());
+    ExpectIntEQ(wolfSSL_X509_NAME_add_entry_by_txt(name, "commonName",
+        MBSTRING_UTF8, (const byte*)"mldsa-req", -1, -1, 0), WOLFSSL_SUCCESS);
+    ExpectIntEQ(wolfSSL_X509_REQ_set_subject_name(req, name), WOLFSSL_SUCCESS);
+    ExpectIntEQ(wolfSSL_X509_REQ_set_pubkey(req, pkey), WOLFSSL_SUCCESS);
+
+    ExpectIntEQ(wolfSSL_X509_REQ_sign(req, pkey, wolfSSL_EVP_sha256()),
+        WOLFSSL_SUCCESS);
+
+    /* Round-trip the signed request through DER to prove the encoding is a
+     * complete, parseable CSR (an ML-DSA signature does not fit the old
+     * fixed 2048-byte buffer). */
+    ExpectIntGT((derSz = wolfSSL_i2d_X509_REQ(req, &der)), 0);
+    ExpectNotNull(der);
+    ExpectNotNull(parsed = wolfSSL_X509_REQ_d2i(NULL, der, derSz));
+
+    /* Verify the signature with the public key from the parsed request. */
+    ExpectNotNull(pubkey = wolfSSL_X509_get_pubkey(parsed));
+    ExpectIntEQ(wolfSSL_EVP_PKEY_id(pubkey), WC_EVP_PKEY_DILITHIUM);
+    ExpectIntEQ(wolfSSL_X509_REQ_verify(parsed, pubkey), WOLFSSL_SUCCESS);
+
+    wolfSSL_EVP_PKEY_free(pubkey);
+    wolfSSL_X509_free(parsed);
+    XFREE(der, NULL, DYNAMIC_TYPE_OPENSSL);
+    wolfSSL_X509_NAME_free(name);
+    wolfSSL_X509_free(req);
+    wolfSSL_EVP_PKEY_free(pkey);
+#endif
+    return EXPECT_RESULT();
+}

tests/api/test_x509.h

@@ -30,6 +30,7 @@ int test_x509_time_field_overread_via_tls(void);
 int test_x509_CertFromX509_akid_overflow(void);
 int test_x509_ReqCertFromX509_skid_overflow(void);
 int test_x509_ReqCertFromX509_skid_boundary(void);
+int test_x509_REQ_sign_mldsa(void);
 
 #define TEST_X509_DECLS                                                        \
     TEST_DECL_GROUP("x509", test_x509_rfc2818_verification_callback),          \
@@ -39,6 +40,7 @@ int test_x509_ReqCertFromX509_skid_boundary(void);
     TEST_DECL_GROUP("x509", test_x509_time_field_overread_via_tls),             \
     TEST_DECL_GROUP("x509", test_x509_CertFromX509_akid_overflow),             \
     TEST_DECL_GROUP("x509", test_x509_ReqCertFromX509_skid_overflow),          \
-    TEST_DECL_GROUP("x509", test_x509_ReqCertFromX509_skid_boundary)
+    TEST_DECL_GROUP("x509", test_x509_ReqCertFromX509_skid_boundary),        \
+    TEST_DECL_GROUP("x509", test_x509_REQ_sign_mldsa)
 
 #endif /* WOLFCRYPT_TEST_X509_H */