swdev: add AES-ECB only testing option

.github/workflows/cryptocb-only.yml

@@ -37,6 +37,13 @@ jobs:
           # software path via cryptocb.
           - name: AES
             cppflags: -DWOLF_CRYPTO_CB_ONLY_AES
+          # Same as AES but tells swdev to refuse AES-GCM (SWDEV_AES_ONLYECB).
+          # That forces the parent's CB_ONLY_AES host-side GCM software path:
+          # GHASH runs on the host while AES-CTR blocks dispatch back through
+          # cryptocb ECB.  The AES entry above instead has swdev handle GCM
+          # end-to-end, so the host-side GCM path is otherwise uncovered.
+          - name: AES_GCM_via_ECB
+            cppflags: -DWOLF_CRYPTO_CB_ONLY_AES -DSWDEV_AES_ONLYECB
           # All four ONLY_* macros at once: every supported software primitive
           # is stripped and dispatched through cryptocb.  Catches any cross-
           # algorithm call that a single-strip entry would still resolve via

tests/swdev/swdev.c

@@ -357,7 +357,12 @@ static int swdev_aes_ecb(wc_CryptoInfo* info)
 }
 #endif /* HAVE_AES_ECB || WOLFSSL_AES_DIRECT */
 
-#ifdef HAVE_AESGCM
+/* SWDEV_AES_ONLYECB: when defined, swdev's AES backend returns
+ * CRYPTOCB_UNAVAILABLE for AES-GCM so the parent's CB_ONLY_AES host-side
+ * GCM software path runs (GHASH on the host; AES-CTR blocks dispatch back
+ * through cryptocb ECB). Without this macro, swdev handles GCM end-to-end
+ * and the host-side software path is never exercised. */
+#if defined(HAVE_AESGCM) && !defined(SWDEV_AES_ONLYECB)
 static int swdev_aes_gcm(wc_CryptoInfo* info)
 {
     Aes* aes = info->cipher.enc ? info->cipher.aesgcm_enc.aes :
@@ -401,7 +406,7 @@ static int swdev_aes_gcm(wc_CryptoInfo* info)
     wc_AesFree(&shadow);
     return ret;
 }
-#endif /* HAVE_AESGCM */
+#endif /* HAVE_AESGCM && !SWDEV_AES_ONLYECB */
 
 #ifdef HAVE_AESCCM
 static int swdev_aes_ccm(wc_CryptoInfo* info)
@@ -527,7 +532,7 @@ WC_SWDEV_EXPORT int wc_SwDev_Callback(int devId, wc_CryptoInfo* info,
         case WC_CIPHER_AES_ECB:
             return swdev_aes_ecb(info);
     #endif
-    #ifdef HAVE_AESGCM
+    #if defined(HAVE_AESGCM) && !defined(SWDEV_AES_ONLYECB)
         case WC_CIPHER_AES_GCM:
             return swdev_aes_gcm(info);
     #endif