Implement timeout capability. Apply timeout to crypto response

src/wh_client.c

@@ -81,6 +81,15 @@ int wh_Client_Init(whClientContext* c, const whClientConfig* config)
     c->cancelCb = config->cancelCb;
 #endif
 
+#ifdef WOLFHSM_CFG_ENABLE_TIMEOUT
+    if (config->respTimeoutConfig != NULL) {
+        rc = wh_Timeout_Init(c->respTimeout, config->respTimeoutConfig);
+        if (rc != 0) {
+            return rc;
+        }
+    }
+#endif
+
     rc = wh_CommClient_Init(c->comm, config->comm);
 
 #ifndef WOLFHSM_CFG_NO_CRYPTO
@@ -199,6 +208,31 @@ int wh_Client_RecvResponse(whClientContext *c,
     return rc;
 }
 
+int wh_Client_RecvResponseTimeout(whClientContext *c,
+        uint16_t *out_group, uint16_t *out_action,
+        uint16_t *out_size, void* data, whTimeoutCtx *timeout)
+{
+    int ret;
+
+    if ((c == NULL) || (timeout == NULL)) {
+        return WH_ERROR_BADARGS;
+    }
+
+    ret = wh_Timeout_Start(timeout);
+    if (ret != WH_ERROR_OK) {
+        return ret;
+    }
+
+    do {
+        ret = wh_Client_RecvResponse(c, out_group, out_action, out_size, data);
+        if ((ret == WH_ERROR_NOTREADY) && wh_Timeout_Expired(timeout)) {
+            return WH_ERROR_TIMEOUT;
+        }
+    } while (ret == WH_ERROR_NOTREADY);
+
+    return ret;
+}
+
 int wh_Client_CommInitRequest(whClientContext* c)
 {
     whMessageCommInitRequest msg = {0};

src/wh_timeout.c

@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2025 wolfSSL Inc.
+ *
+ * This file is part of wolfHSM.
+ *
+ * wolfHSM is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * wolfHSM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with wolfHSM.  If not, see <http://www.gnu.org/licenses/>.
+ */
+/*
+ * src/wh_timeout.c
+ */
+
+/* Pick up compile-time configuration */
+#include "wolfhsm/wh_settings.h"
+
+#include "wolfhsm/wh_timeout.h"
+#include "wolfhsm/wh_error.h"
+
+int wh_Timeout_Init(whTimeoutCtx* timeout, const whTimeoutConfig* config)
+{
+    if ((timeout == NULL) || (config == NULL)) {
+        return WH_ERROR_BADARGS;
+    }
+
+    timeout->startUs = 0;
+    timeout->timeoutUs = config->timeoutUs;
+    timeout->expiredCb = config->expiredCb;
+    timeout->cbCtx = config->cbCtx;
+
+    return WH_ERROR_OK;
+}
+
+int wh_Timeout_Set(whTimeoutCtx* timeout, uint64_t timeoutUs)
+{
+    if (timeout == NULL) {
+        return WH_ERROR_BADARGS;
+    }
+
+    timeout->timeoutUs = timeoutUs;
+
+    return WH_ERROR_OK;
+}
+
+int wh_Timeout_Start(whTimeoutCtx* timeout)
+{
+    if (timeout == NULL) {
+        return WH_ERROR_BADARGS;
+    }
+
+    timeout->startUs = WH_GETTIME_US();
+
+    return WH_ERROR_OK;
+}
+
+int wh_Timeout_Stop(whTimeoutCtx* timeout)
+{
+    if (timeout == NULL) {
+        return WH_ERROR_BADARGS;
+    }
+
+    timeout->startUs = 0;
+    timeout->timeoutUs = 0;
+
+    return WH_ERROR_OK;
+}
+
+int wh_Timeout_Expired(const whTimeoutCtx* timeout)
+{
+    uint64_t nowUs = 0;
+    int expired = 0;
+
+    if (timeout == NULL) {
+        return 0;
+    }
+
+    if (timeout->timeoutUs == 0) {
+        return 0;
+    }
+
+    nowUs = WH_GETTIME_US();
+    expired = (nowUs - timeout->startUs) >= timeout->timeoutUs;
+    if (expired && (timeout->expiredCb != NULL)) {
+        timeout->expiredCb(timeout->cbCtx);
+    }
+    return expired;
+}

test/config/wolfhsm_cfg.h

@@ -71,4 +71,6 @@
 /* Allow persistent NVM artifacts in tests */
 #define WOLFHSM_CFG_TEST_ALLOW_PERSISTENT_NVM_ARTIFACTS
 
+#define WOLFHSM_CFG_ENABLE_TIMEOUT
+
 #endif /* WOLFHSM_CFG_H_ */

test/wh_test.c

@@ -40,6 +40,7 @@
 #include "wh_test_keywrap.h"
 #include "wh_test_multiclient.h"
 #include "wh_test_log.h"
+#include "wh_test_timeout.h"
 
 #if defined(WOLFHSM_CFG_CERTIFICATE_MANAGER)
 #include "wh_test_cert.h"
@@ -71,6 +72,9 @@ int whTest_Unit(void)
     /* Component Tests */
     WH_TEST_ASSERT(0 == whTest_Flash_RamSim());
     WH_TEST_ASSERT(0 == whTest_NvmFlash());
+#ifdef WOLFHSM_CFG_ENABLE_TIMEOUT
+    WH_TEST_ASSERT(0 == whTest_Timeout());
+#endif
 #ifdef WOLFHSM_CFG_LOGGING
     WH_TEST_ASSERT(0 == whTest_Log());
 #endif

test/wh_test_timeout.c

@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2024 wolfSSL Inc.
+ *
+ * This file is part of wolfHSM.
+ *
+ * wolfHSM is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * wolfHSM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with wolfHSM.  If not, see <http://www.gnu.org/licenses/>.
+ */
+/*
+ * test/wh_test_timeout.c
+ *
+ */
+
+#include <stdint.h>
+
+#include "wolfhsm/wh_settings.h"
+#include "wolfhsm/wh_timeout.h"
+#include "wolfhsm/wh_error.h"
+
+#include "wh_test_common.h"
+#include "wh_test_timeout.h"
+
+static void whTest_TimeoutCb(void* ctx)
+{
+    int* counter = (int*)ctx;
+    if (counter != NULL) {
+        (*counter)++;
+    }
+}
+
+int whTest_Timeout(void)
+{
+    int cb_count = 0;
+    whTimeoutConfig cfg;
+    whTimeoutCtx timeout[1];
+
+    cfg.timeoutUs = 1;
+    cfg.expiredCb = whTest_TimeoutCb;
+    cfg.cbCtx = &cb_count;
+
+    wh_Timeout_Init(timeout, &cfg);
+    WH_TEST_ASSERT_RETURN(timeout->startUs == 0);
+    WH_TEST_ASSERT_RETURN(timeout->timeoutUs == cfg.timeoutUs);
+    WH_TEST_ASSERT_RETURN(timeout->expiredCb == cfg.expiredCb);
+    WH_TEST_ASSERT_RETURN(timeout->cbCtx == cfg.cbCtx);
+
+    wh_Timeout_Start(timeout);
+    WH_TEST_ASSERT_RETURN(timeout->timeoutUs > 0);
+
+    wh_Timeout_Stop(timeout);
+    WH_TEST_ASSERT_RETURN(timeout->startUs == 0);
+    WH_TEST_ASSERT_RETURN(timeout->timeoutUs == 0);
+
+    /* No expiration when disabled */
+    WH_TEST_ASSERT_RETURN(wh_Timeout_Expired(timeout) == 0);
+
+    WH_TEST_ASSERT_RETURN(wh_Timeout_Init(0, 0) == WH_ERROR_BADARGS);
+    WH_TEST_ASSERT_RETURN(wh_Timeout_Set(0, 0) == WH_ERROR_BADARGS);
+    WH_TEST_ASSERT_RETURN(wh_Timeout_Start(0) == WH_ERROR_BADARGS);
+    WH_TEST_ASSERT_RETURN(wh_Timeout_Stop(0) == WH_ERROR_BADARGS);
+    WH_TEST_ASSERT_RETURN(wh_Timeout_Expired(0) == 0);
+
+    return 0;
+}

test/wh_test_timeout.h

@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2024 wolfSSL Inc.
+ *
+ * This file is part of wolfHSM.
+ *
+ * wolfHSM is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * wolfHSM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with wolfHSM.  If not, see <http://www.gnu.org/licenses/>.
+ */
+/*
+ * test/wh_test_timeout.h
+ *
+ */
+
+#ifndef TEST_WH_TEST_TIMEOUT_H_
+#define TEST_WH_TEST_TIMEOUT_H_
+
+/**
+ * Runs timeout module tests.
+ *
+ * @return 0 on success and a non-zero error code on failure.
+ */
+int whTest_Timeout(void);
+
+#endif /* TEST_WH_TEST_TIMEOUT_H_ */

wolfhsm/wh_client.h

@@ -48,6 +48,7 @@
 
 /* Component includes */
 #include "wolfhsm/wh_comm.h"
+#include "wolfhsm/wh_timeout.h"
 #include "wolfhsm/wh_message_customcb.h"
 #ifdef WOLFHSM_CFG_DMA
 #include "wolfhsm/wh_dma.h"
@@ -121,6 +122,9 @@ struct whClientContext_t {
     uint8_t          cancelable;
     whClientCancelCb cancelCb;
 #endif
+#ifdef WOLFHSM_CFG_ENABLE_TIMEOUT
+    whTimeoutCtx respTimeout[1];
+#endif
 #ifdef WOLFHSM_CFG_DMA
     whClientDmaContext dma;
 #endif /* WOLFHSM_CFG_DMA */
@@ -135,6 +139,9 @@ struct whClientConfig_t {
 #ifdef WOLFHSM_CFG_DMA
     whClientDmaConfig* dmaConfig;
 #endif /* WOLFHSM_CFG_DMA */
+#ifdef WOLFHSM_CFG_ENABLE_TIMEOUT
+    whTimeoutConfig* respTimeoutConfig;
+#endif /* WOLFHSM_CFG_ENABLE_TIMEOUT*/
 };
 typedef struct whClientConfig_t whClientConfig;
 
@@ -193,6 +200,23 @@ int wh_Client_SendRequest(whClientContext* c, uint16_t group, uint16_t action,
 int wh_Client_RecvResponse(whClientContext* c, uint16_t* out_group,
                            uint16_t* out_action, uint16_t* out_size,
                            void* data);
+#ifdef WOLFHSM_CFG_ENABLE_TIMEOUT
+/**
+ * Receives a response from the server with a timeout window.
+ *
+ * @param c The client context.
+ * @param out_group Pointer to store the received group value.
+ * @param out_action Pointer to store the received action value.
+ * @param out_size Pointer to store the received size value.
+ * @param data Pointer to store the received data.
+ * @param timeout The timeout context to use.
+ * @return 0 if successful, WH_ERROR_TIMEOUT on expiration, or a negative value
+ * if an error occurred.
+ */
+int wh_Client_RecvResponseTimeout(whClientContext* c, uint16_t* out_group,
+                                  uint16_t* out_action, uint16_t* out_size,
+                                  void* data, whTimeoutCtx* timeout);
+#endif /* WOLFHSM_CFG_ENABLE_TIMEOUT */
 
 
 /** Comm component functions */

wolfhsm/wh_error.h

@@ -45,6 +45,7 @@ enum WH_ERROR_ENUM {
                                       compile-time configuration */
     WH_ERROR_USAGE =
         -2009, /* Operation not permitted based on object/key usage flags */
+    WH_ERROR_TIMEOUT = -2010,     /* Timeout occurred. */
 
     /* NVM and keystore specific status returns */
     WH_ERROR_LOCKED      = -2100, /* Unlock and retry if necessary */

wolfhsm/wh_settings.h

@@ -57,6 +57,9 @@
  *  WOLFHSM_CFG_ENABLE_SERVER - If defined, include server-specific
  * functionality
  *
+ *  WOLFHSM_CFG_ENABLE_TIMEOUT - If defined, include timeout helpers and
+ * client response timeout support.
+ *
  *  WOLFHSM_CFG_NVM_OBJECT_COUNT - Number of objects in ram and disk directories
  *      Default: 32
  *