PR review: default H5 TZ wolfHSM test to UART (bkpt opt-in), gate server AES/HMAC to TZ engine, bump wolfHSM pin to merged main

Author: aidangarske

Makefile

@@ -199,6 +199,9 @@ OBJS+=$(WOLFCRYPT_OBJS)
 OBJS+=$(PUBLIC_KEY_OBJS)
 OBJS+=$(WOLFHSM_OBJS)
 
+# Vendored wolfHSM sources: keep cosmetic unused-parameter warnings non-fatal
+$(WOLFHSM_OBJS): CFLAGS += -Wno-error=unused-parameter
+
 CFLAGS+= \
   -I"." -I"include/" -I"$(WOLFBOOT_LIB_WOLFSSL)" \
   -Wno-array-bounds \

docs/wolfHSM.md

@@ -254,10 +254,10 @@ cp config/examples/stm32h5-tz-wolfhsm.config .config
 make
 ```
 
-For on-board hardware testing, add `WOLFBOOT_TZ_TEST_NO_BKPT=1` so the auto-test prints a UART pass/fail line and idles in `while (1)` instead of issuing `bkpt #0x7f` (which HardFaults on real silicon without a debugger):
+By default the auto-test prints a UART pass/fail line and idles in `while (1)`, which is safe on real silicon. For emulator or under-debugger runs that signal pass/fail via a breakpoint, add `WOLFBOOT_TZ_TEST_BKPT=1` so the auto-test issues `bkpt` instead (this HardFaults on real silicon without a debugger attached):
 
 ```sh
-make WOLFBOOT_TZ_TEST_NO_BKPT=1
+make WOLFBOOT_TZ_TEST_BKPT=1
 ```
 
 ### Flash
@@ -283,7 +283,7 @@ wolfHSM first boot path, committing key to NVM
 wolfHSM NSC tests passed
 ```
 
-The default build raises `bkpt #0x7d` on first-boot success and `bkpt #0x7f` on second-boot success (after the persisted key is reloaded from flash on reset). The `WOLFBOOT_TZ_TEST_NO_BKPT=1` build prints a final `WOLFHSM_TZ_TEST_PASS` UART line instead. Reset the board (no re-flash) to verify persistence; the second boot prints `wolfHSM second boot path, restored persisted key`.
+The default build prints a final `WOLFHSM_TZ_TEST_PASS` UART line on success. The `WOLFBOOT_TZ_TEST_BKPT=1` build raises `bkpt #0x7d` on first-boot success and `bkpt #0x7f` on second-boot success (after the persisted key is reloaded from flash on reset) instead, for emulator and debugger runs. Reset the board (no re-flash) to verify persistence; the second boot prints `wolfHSM second boot path, restored persisted key`.
 
 ### Notes
 

include/user_settings.h

@@ -785,39 +785,10 @@ extern int tolower(int c);
 #   define WOLFSSL_KEY_GEN
 #endif
 
-/* Crypto algorithms exercised by the wolfHSM client test suite over
- * the NSC bridge. These are SECURE-SIDE only - the wolfHSM server
- * needs AES/HKDF/SHA384/512 to handle the test requests. Gated out
- * of the wolfHSM client build (which has NO_AES) and out of host
- * unit tests (UNIT_TEST), neither of which want AES dragged in. */
+/* Secure-side sizing common to any wolfHSM server build (TZ engine and
+ * the verify-only cert-chain server). Gated out of host unit tests. */
 #if (defined(WOLFBOOT_ENABLE_WOLFHSM_SERVER) || \
      defined(WOLFCRYPT_TZ_WOLFHSM)) && !defined(UNIT_TEST)
-    /* Earlier guards in this file set NO_AES and NO_HMAC for the
-     * verify-only bootloader path. The wolfHSM server needs both AES
-     * and HMAC (HKDF builds on HMAC), so drop them here. */
-#   undef NO_AES
-#   undef NO_HMAC
-#   ifndef WOLFSSL_AES_DIRECT
-#       define WOLFSSL_AES_DIRECT
-#   endif
-#   ifndef HAVE_HKDF
-#       define HAVE_HKDF
-#   endif
-#   ifndef WOLFSSL_AES_COUNTER
-#       define WOLFSSL_AES_COUNTER
-#   endif
-#   ifndef HAVE_AESCTR
-#       define HAVE_AESCTR
-#   endif
-#   ifndef WOLFSSL_AES_GCM
-#       define WOLFSSL_AES_GCM
-#   endif
-#   ifndef HAVE_AESGCM
-#       define HAVE_AESGCM
-#   endif
-#   ifndef GCM_TABLE_4BIT
-#       define GCM_TABLE_4BIT
-#   endif
     /* Match NS-side WC_MAX_DIGEST_SIZE. NS test-app/wcs/user_settings.h
      * enables WOLFSSL_SHA3 which sets WC_MAX_DIGEST_SIZE = 64. Without
      * SHA384/SHA512 on the secure side, WC_MAX_DIGEST_SIZE caps at
@@ -842,6 +813,36 @@ extern int tolower(int c);
 #   endif
 #endif /* WOLFBOOT_ENABLE_WOLFHSM_SERVER || WOLFCRYPT_TZ_WOLFHSM, !UNIT_TEST */
 
+/* AES/HMAC/HKDF are only needed by the STM32H5 TrustZone engine, whose
+ * non-secure client routes general crypto (AES/HMAC/HKDF) through the
+ * secure server. The verify-only cert-chain server does not service these
+ * requests, so it keeps the NO_AES/NO_HMAC set earlier in this file. */
+#if defined(WOLFCRYPT_TZ_WOLFHSM) && !defined(UNIT_TEST)
+#   undef NO_AES
+#   undef NO_HMAC
+#   ifndef WOLFSSL_AES_DIRECT
+#       define WOLFSSL_AES_DIRECT
+#   endif
+#   ifndef HAVE_HKDF
+#       define HAVE_HKDF
+#   endif
+#   ifndef WOLFSSL_AES_COUNTER
+#       define WOLFSSL_AES_COUNTER
+#   endif
+#   ifndef HAVE_AESCTR
+#       define HAVE_AESCTR
+#   endif
+#   ifndef WOLFSSL_AES_GCM
+#       define WOLFSSL_AES_GCM
+#   endif
+#   ifndef HAVE_AESGCM
+#       define HAVE_AESGCM
+#   endif
+#   ifndef GCM_TABLE_4BIT
+#       define GCM_TABLE_4BIT
+#   endif
+#endif /* WOLFCRYPT_TZ_WOLFHSM && !UNIT_TEST */
+
 #if defined(WOLFBOOT_ENABLE_WOLFHSM_SERVER) && \
     defined(WOLFBOOT_CERT_CHAIN_VERIFY)
 #   define NO_TLS

lib/wolfHSM

@@ -1493,10 +1493,7 @@ ifeq ($(WOLFHSM_SERVER),1)
   WOLFCRYPT_OBJS += \
     $(WOLFBOOT_LIB_WOLFSSL)/wolfcrypt/src/cryptocb.o \
     $(WOLFBOOT_LIB_WOLFSSL)/wolfcrypt/src/coding.o \
-    $(WOLFBOOT_LIB_WOLFSSL)/wolfcrypt/src/random.o \
-    $(WOLFBOOT_LIB_WOLFSSL)/wolfcrypt/src/hmac.o \
-    $(WOLFBOOT_LIB_WOLFSSL)/wolfcrypt/src/aes.o \
-    $(WOLFBOOT_LIB_WOLFSSL)/wolfcrypt/src/wc_encrypt.o
+    $(WOLFBOOT_LIB_WOLFSSL)/wolfcrypt/src/random.o
   # SHA-384/512 are used by the wolfHSM crypto handlers (HKDF, larger
   # ECDSA hash sizes, etc.). Always link sha512.o except when ED25519
   # is the signature algorithm, which already pulls it in.

options.mk

@@ -387,8 +387,8 @@ ifeq ($(TZEN),1)
         CFLAGS+=-DWOLFHSM_CFG_COMM_DATA_LEN=1280
         CFLAGS+=-DWOLFHSM_CFG_PORT_ARMV8M_TZ_NSC
         CFLAGS+=-DWOLFHSM_CFG_NO_SYS_TIME
-        ifeq ($(WOLFBOOT_TZ_TEST_NO_BKPT),1)
-            CFLAGS+=-DWOLFBOOT_TZ_TEST_NO_BKPT
+        ifeq ($(WOLFBOOT_TZ_TEST_BKPT),1)
+            CFLAGS+=-DWOLFBOOT_TZ_TEST_BKPT
         endif
         CFLAGS+=-I"$(WOLFBOOT_LIB_WOLFHSM)"
         CFLAGS+=-I"$(WOLFBOOT_LIB_WOLFHSM)/port/armv8m-tz"

test-app/Makefile

@@ -1510,21 +1510,21 @@ void main(void)
 
 #ifdef WOLFCRYPT_TZ_WOLFHSM
     ret = cmd_wolfhsm_test(NULL);
-#ifdef WOLFBOOT_TZ_TEST_NO_BKPT
+#ifdef WOLFBOOT_TZ_TEST_BKPT
+    if (ret == WOLFHSM_TEST_FIRST_BOOT_OK)
+        asm volatile ("bkpt #0x7d");
+    else if (ret == WOLFHSM_TEST_SECOND_BOOT_OK)
+        asm volatile ("bkpt #0x7f");
+    else
+        asm volatile ("bkpt #0x7e");
+#else
     if (ret == WOLFHSM_TEST_FIRST_BOOT_OK || ret == WOLFHSM_TEST_SECOND_BOOT_OK) {
         printf("WOLFHSM_TZ_TEST_PASS\r\n");
         while (1) { }
     } else {
         printf("WOLFHSM_TZ_TEST_FAIL\r\n");
         while (1) { }
     }
-#else
-    if (ret == WOLFHSM_TEST_FIRST_BOOT_OK)
-        asm volatile ("bkpt #0x7d");
-    else if (ret == WOLFHSM_TEST_SECOND_BOOT_OK)
-        asm volatile ("bkpt #0x7f");
-    else
-        asm volatile ("bkpt #0x7e");
 #endif
 #endif