Align wolfSSL_set1_groups_list() arg handling with OpenSSL

Align the argument parsing and handling of input group names to align it
with OpenSSL behavior:
* Do a case-insensitive comparison of the input names with our names
* Add aliases for "MLKEMxxx" groups without underscores in addition to
  our names with underscores (keep our for backward compatibility)
* Extend unit tests for both

Author: Frauschi

src/ssl.c

@@ -13910,6 +13910,10 @@ const WOLF_EC_NIST_NAME kNistCurves[] = {
     {CURVE_NAME("ML_KEM_512"), WOLFSSL_ML_KEM_512, WOLFSSL_ML_KEM_512},
     {CURVE_NAME("ML_KEM_768"), WOLFSSL_ML_KEM_768, WOLFSSL_ML_KEM_768},
     {CURVE_NAME("ML_KEM_1024"), WOLFSSL_ML_KEM_1024, WOLFSSL_ML_KEM_1024},
+    /* Aliases accepting the OpenSSL/IANA spelling without underscores. */
+    {CURVE_NAME("MLKEM512"), WOLFSSL_ML_KEM_512, WOLFSSL_ML_KEM_512},
+    {CURVE_NAME("MLKEM768"), WOLFSSL_ML_KEM_768, WOLFSSL_ML_KEM_768},
+    {CURVE_NAME("MLKEM1024"), WOLFSSL_ML_KEM_1024, WOLFSSL_ML_KEM_1024},
 #if defined(HAVE_ECC)
     #ifdef WOLFSSL_PQC_HYBRIDS
     {CURVE_NAME("SecP256r1MLKEM768"), WOLFSSL_SECP256R1MLKEM768,
@@ -14008,7 +14012,7 @@ int set_curves_list(WOLFSSL* ssl, WOLFSSL_CTX *ctx, const char* names,
 
         for (nist_name = kNistCurves; nist_name->name != NULL; nist_name++) {
             if (len == nist_name->name_len &&
-                    XSTRNCMP(name, nist_name->name, (size_t)len) == 0) {
+                    XSTRNCASECMP(name, nist_name->name, (size_t)len) == 0) {
                 curve = nist_name->curve;
                 break;
             }

tests/api/test_ssl_ext.c

@@ -166,6 +166,29 @@ int test_wolfSSL_set1_groups_list_ext(void)
     ExpectIntEQ(wolfSSL_CTX_set1_groups_list(ctx, "P-256"), WOLFSSL_SUCCESS);
     ExpectIntEQ(wolfSSL_set1_groups_list(ssl, "P-256"), WOLFSSL_SUCCESS);
 
+    /* Group name matching is case-insensitive, matching OpenSSL behavior.
+     * P-256 is the same curve as secp256r1; use it for the mixed-case list so
+     * the test does not depend on additional curves being compiled in. */
+    ExpectIntEQ(wolfSSL_CTX_set1_groups_list(ctx, "p-256"), WOLFSSL_SUCCESS);
+    ExpectIntEQ(wolfSSL_set1_groups_list(ssl, "p-256"), WOLFSSL_SUCCESS);
+    ExpectIntEQ(wolfSSL_CTX_set1_groups_list(ctx, "p-256:SECP256R1"),
+        WOLFSSL_SUCCESS);
+    ExpectIntEQ(wolfSSL_set1_groups_list(ssl, "p-256:SECP256R1"),
+        WOLFSSL_SUCCESS);
+
+#if defined(WOLFSSL_HAVE_MLKEM) && !defined(WOLFSSL_NO_ML_KEM) && \
+    !defined(WOLFSSL_TLS_NO_MLKEM_STANDALONE)
+    /* ML-KEM groups are accepted by both the wolfSSL spelling ("ML_KEM_512")
+     * and the OpenSSL/IANA spelling without underscores ("MLKEM512"). These
+     * standalone (non-hybrid) ML-KEM groups are only usable as TLS key
+     * exchange when WOLFSSL_TLS_NO_MLKEM_STANDALONE is not defined. */
+    ExpectIntEQ(wolfSSL_CTX_set1_groups_list(ctx, "ML_KEM_512"),
+        WOLFSSL_SUCCESS);
+    ExpectIntEQ(wolfSSL_CTX_set1_groups_list(ctx, "MLKEM512"), WOLFSSL_SUCCESS);
+    ExpectIntEQ(wolfSSL_set1_groups_list(ssl, "MLKEM768"), WOLFSSL_SUCCESS);
+    ExpectIntEQ(wolfSSL_set1_groups_list(ssl, "mlkem1024"), WOLFSSL_SUCCESS);
+#endif
+
     wolfSSL_free(ssl);
     wolfSSL_CTX_free(ctx);
 #endif