Enforce server-side client identity assignment in CommInit handshake

benchmark/wh_bench.c

@@ -863,6 +863,7 @@ static whCommServerConfig          g_mem_cs_conf = {
              .transport_context = (void*)&g_mem_tmsc,
              .transport_config  = (void*)&g_mem_tmcf,
              .server_id         = 124,
+             .client_id         = WH_BENCH_CLIENT_ID,
 };
 
 /* Helper function to configure client transport based on type */
@@ -981,6 +982,7 @@ static int _configureServerTransport(whBenchTransportType transport,
                 .transport_context = (void*)&tscShm,
                 .transport_config  = (void*)&myshmconfig,
                 .server_id         = 57,
+                .client_id         = WH_BENCH_CLIENT_ID,
             };
 
             memset(&tscShm, 0, sizeof(posixTransportShmServerContext));
@@ -1001,6 +1003,7 @@ static int _configureServerTransport(whBenchTransportType transport,
                 .transport_context = (void*)&tscTcp,
                 .transport_config  = (void*)&mytcpconfig,
                 .server_id         = 57,
+                .client_id         = WH_BENCH_CLIENT_ID,
             };
 
             memset(&tscTcp, 0, sizeof(posixTransportTcpServerContext));

docs/src-ja/chapter03.md

@@ -132,6 +132,7 @@ whCommServerConfig commServerCfg = {
        .transport_context  = (void*)transportMemServerCtx,
        .transport_config   = (void*)transportMemCfg,
        .server_id          = 456, /* 一意のサーバー識別子 */
+       .client_id          = 123, /* 接続するクライアントに割り当てるID */
 };
 
 /* サーバーNVMコンテキストの初期化 */

docs/src/chapter03.md

@@ -130,6 +130,7 @@ whCommServerConfig commServerCfg = {
         .transport_context  = (void*)transportMemServerCtx,
         .transport_config   = (void*)transportMemCfg,
         .server_id          = 456, /* unique server identifier */
+        .client_id          = 123, /* identity assigned to the connecting client */
 };
 
 /* Initialize the server NVM context */

examples/posix/wh_posix_server/wh_posix_server_cfg.c

@@ -62,6 +62,7 @@ int wh_PosixServer_ExampleShmDmaConfig(void* conf)
     s_comm.transport_context = (void*)&tscDma;
     s_comm.transport_config  = (void*)&shmConfig;
     s_comm.server_id         = WH_POSIX_SERVER_ID;
+    s_comm.client_id         = WH_POSIX_CLIENT_ID;
 
     s_conf->dmaConfig   = &dmaConfig;
     s_conf->comm_config = &s_comm;
@@ -89,6 +90,7 @@ int wh_PosixServer_ExampleShmConfig(void* conf)
     s_comm.transport_context = (void*)&tscShm;
     s_comm.transport_config  = (void*)&shmConfig;
     s_comm.server_id         = WH_POSIX_SERVER_ID;
+    s_comm.client_id         = WH_POSIX_CLIENT_ID;
 
     s_conf->comm_config = &s_comm;
 
@@ -112,6 +114,7 @@ int wh_PosixServer_ExampleTcpConfig(void* conf)
     s_comm.transport_context = (void*)&tscTcp;
     s_comm.transport_config  = (void*)&tcpConfig;
     s_comm.server_id         = WH_POSIX_SERVER_ID;
+    s_comm.client_id         = WH_POSIX_CLIENT_ID;
 
     s_conf->comm_config = &s_comm;
 
@@ -176,6 +179,7 @@ int wh_PosixServer_ExampleTlsConfig(void* ctx)
     s_comm.transport_context = (void*)&tscTls;
     s_comm.transport_config  = (void*)&tlsConfig;
     s_comm.server_id         = WH_POSIX_SERVER_ID;
+    s_comm.client_id         = WH_POSIX_CLIENT_ID;
 
     s_conf->comm_config = &s_comm;
 

src/wh_comm.c

@@ -229,6 +229,7 @@ int wh_CommServer_Init(whCommServer* context, const whCommServerConfig* config,
     context->transport_context  = config->transport_context;
     context->transport_cb       = config->transport_cb;
     context->server_id          = config->server_id;
+    context->expected_client_id = config->client_id;
 
     if (context->transport_cb->Init != NULL) {
         rc = context->transport_cb->Init(context->transport_context,

src/wh_server.c

@@ -100,6 +100,14 @@ int wh_Server_Init(whServerContext* server, whServerConfig* config)
     }
 #endif /* WOLFHSM_CFG_LOGGING */
 
+#ifdef WOLFHSM_CFG_GLOBAL_KEYS
+    if (config->comm_config != NULL &&
+        config->comm_config->client_id == WH_KEYUSER_GLOBAL) {
+        (void)wh_Server_Cleanup(server);
+        return WH_ERROR_BADARGS;
+    }
+#endif
+
     rc = wh_CommServer_Init(server->comm, config->comm_config,
             wh_Server_SetConnectedCb, (void*)server);
     if (rc != 0) {
@@ -189,23 +197,32 @@ static int _wh_Server_HandleCommRequest(whServerContext* server,
         wh_MessageComm_TranslateInitRequest(magic,
                 (whMessageCommInitRequest*)req_packet, &req);
 
+        /* Use server-assigned identity from config rather than trusting
+         * the client-supplied value. This prevents a malicious client from
+         * claiming another client's identity to access its keys. */
+        server->comm->client_id = server->comm->expected_client_id;
+
 #ifdef WOLFHSM_CFG_GLOBAL_KEYS
         /* USER=0 is reserved for global keys, client_id must be non-zero */
-        if (req.client_id == WH_KEYUSER_GLOBAL) {
+        if (server->comm->client_id == WH_KEYUSER_GLOBAL) {
             *out_resp_size = 0;
             return WH_ERROR_BADARGS;
         }
 #endif
 
-        /* Process the init action */
-        server->comm->client_id = req.client_id;
+        if (req.client_id != server->comm->client_id) {
+            WH_LOG_F(&server->log, WH_LOG_LEVEL_SECEVENT,
+                     "CommInit: client claimed id=0x%08X, "
+                     "server assigned id=0x%08X",
+                     req.client_id, server->comm->client_id);
+        }
 
         resp.client_id = server->comm->client_id;
         resp.server_id = server->comm->server_id;
 
         WH_LOG_F(&server->log, WH_LOG_LEVEL_INFO,
-                 "CommInit: client_id=0x%08X, server_id=0x%08X", req.client_id,
-                 resp.server_id);
+                 "CommInit: client_id=0x%08X, server_id=0x%08X",
+                 server->comm->client_id, resp.server_id);
 
         /* Convert the response struct */
         wh_MessageComm_TranslateInitResponse(magic,

test/wh_test_cert.c

@@ -604,6 +604,7 @@ int whTest_CertRamSim(whTestNvmBackendType nvmType)
                  .transport_context = (void*)tmsc,
                  .transport_config  = (void*)tmcf,
                  .server_id         = 124,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
     /* RamSim Flash state and configuration */
     uint8_t memory[FLASH_RAM_SIZE] = {0};

test/wh_test_clientserver.c

@@ -601,6 +601,7 @@ int whTest_ClientServerSequential(whTestNvmBackendType nvmType)
                  .transport_context = (void*)tmsc,
                  .transport_config  = (void*)tmcf,
                  .server_id         = 124,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
 
     /* RamSim Flash state and configuration */
@@ -1590,6 +1591,7 @@ static int wh_ClientServer_MemThreadTest(whTestNvmBackendType nvmType)
                  .transport_context = (void*)tmsc,
                  .transport_config  = (void*)tmcf,
                  .server_id         = 124,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
 
     /* RamSim Flash state and configuration */
@@ -1675,6 +1677,7 @@ static int wh_ClientServer_PosixMemMapThreadTest(whTestNvmBackendType nvmType)
                     .transport_context = (void*)tmsc,
                     .transport_config  = (void*)tmcf,
                     .server_id         = 124,
+                    .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
 
     /* RamSim Flash state and configuration */
@@ -1732,8 +1735,83 @@ static int wh_ClientServer_PosixMemMapThreadTest(whTestNvmBackendType nvmType)
           WOLFHSM_CFG_ENABLE_SERVER */
 
 #if defined(WOLFHSM_CFG_ENABLE_CLIENT) && defined(WOLFHSM_CFG_ENABLE_SERVER)
+static int _testCommInitIdentitySpoofing(void)
+{
+    /* Verify the server ignores client-claimed identity and uses its own
+     * configured expected_client_id during CommInit (C-8 mitigation). */
+    uint8_t              req[BUFFER_SIZE];
+    uint8_t              resp[BUFFER_SIZE];
+    whTransportMemConfig tmcf[1] = {{
+        .req       = (whTransportMemCsr*)req,
+        .req_size  = sizeof(req),
+        .resp      = (whTransportMemCsr*)resp,
+        .resp_size = sizeof(resp),
+    }};
+
+    const uint8_t SPOOFED_CLIENT_ID  = 99;
+    const uint8_t EXPECTED_CLIENT_ID = WH_TEST_DEFAULT_CLIENT_ID;
+
+    /* Client claims a different identity than the server expects */
+    whTransportClientCb         tccb[1]    = {WH_TRANSPORT_MEM_CLIENT_CB};
+    whTransportMemClientContext tmcc[1]    = {0};
+    whCommClientConfig          cc_conf[1] = {{
+                 .transport_cb      = tccb,
+                 .transport_context = (void*)tmcc,
+                 .transport_config  = (void*)tmcf,
+                 .client_id         = SPOOFED_CLIENT_ID,
+    }};
+    whClientContext client[1] = {0};
+    whClientConfig c_conf[1] = {{
+        .comm = cc_conf,
+    }};
+
+    /* Server is configured with the legitimate client identity */
+    whTransportServerCb         tscb[1]    = {WH_TRANSPORT_MEM_SERVER_CB};
+    whTransportMemServerContext tmsc[1]    = {0};
+    whCommServerConfig          cs_conf[1] = {{
+                 .transport_cb      = tscb,
+                 .transport_context = (void*)tmsc,
+                 .transport_config  = (void*)tmcf,
+                 .server_id         = 124,
+                 .client_id         = EXPECTED_CLIENT_ID,
+    }};
+    whServerConfig  s_conf[1] = {{
+        .comm_config = cs_conf,
+    }};
+    whServerContext server[1] = {0};
+
+    uint32_t resp_client_id = 0;
+    uint32_t resp_server_id = 0;
+
+    WH_TEST_RETURN_ON_FAIL(wh_Server_Init(server, s_conf));
+    WH_TEST_RETURN_ON_FAIL(wh_Client_Init(client, c_conf));
+    WH_TEST_RETURN_ON_FAIL(
+        wh_Server_SetConnected(server, WH_COMM_CONNECTED));
+
+    /* Client sends CommInit claiming SPOOFED_CLIENT_ID */
+    WH_TEST_RETURN_ON_FAIL(wh_Client_CommInitRequest(client));
+    WH_TEST_RETURN_ON_FAIL(wh_Server_HandleRequestMessage(server));
+    WH_TEST_RETURN_ON_FAIL(
+        wh_Client_CommInitResponse(client, &resp_client_id, &resp_server_id));
+
+    /* Server must use its configured identity, not the spoofed one */
+    WH_TEST_ASSERT_RETURN(server->comm->client_id == EXPECTED_CLIENT_ID);
+    WH_TEST_ASSERT_RETURN(resp_client_id == EXPECTED_CLIENT_ID);
+    WH_TEST_ASSERT_RETURN(resp_client_id != SPOOFED_CLIENT_ID);
+
+    WH_TEST_RETURN_ON_FAIL(wh_Client_CommCloseRequest(client));
+    WH_TEST_RETURN_ON_FAIL(wh_Server_HandleRequestMessage(server));
+
+    wh_Client_Cleanup(client);
+    wh_Server_Cleanup(server);
+
+    return WH_ERROR_OK;
+}
+
 int whTest_ClientServer(void)
 {
+    WH_TEST_PRINT("Testing CommInit identity spoofing prevention...\n");
+    WH_TEST_ASSERT(0 == _testCommInitIdentitySpoofing());
     WH_TEST_PRINT("Testing client/server sequential: mem...\n");
     WH_TEST_ASSERT(0 == whTest_ClientServerSequential(WH_NVM_TEST_BACKEND_FLASH));
 

test/wh_test_comm.c

@@ -94,6 +94,7 @@ int whTest_CommMem(void)
                  .transport_context = (void*)tmsc,
                  .transport_config  = (void*)tmcf,
                  .server_id         = 124,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
     whCommServer                server[1] = {0};
 
@@ -396,6 +397,7 @@ void wh_CommClientServer_MemThreadTest(void)
                  .transport_context = (void*)css,
                  .transport_config  = (void*)tmcf,
                  .server_id         = 0xF,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
 
     _whCommClientServerThreadTest(c_conf, s_conf);
@@ -435,6 +437,7 @@ void wh_CommClientServer_ShMemThreadTest(void)
                     .transport_context = (void*)css,
                     .transport_config  = (void*)tmcf,
                     .server_id         = 0xF,
+                    .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
 
     _whCommClientServerThreadTest(c_conf, s_conf);
@@ -467,6 +470,7 @@ void wh_CommClientServer_TcpThreadTest(void)
                     .transport_context = (void*)tss,
                     .transport_config  = (void*)mytcpconfig,
                     .server_id         = 0xF,
+                    .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
 
     _whCommClientServerThreadTest(c_conf, s_conf);

test/wh_test_crypto.c

@@ -5751,10 +5751,14 @@ int whTest_CryptoServerConfig(whServerConfig* config)
 #ifdef WOLFHSM_CFG_IS_TEST_SERVER
         /* keep alive for 2 user changes */
         if (am_connected != WH_COMM_CONNECTED && userChange < 2) {
-            if (userChange == 0)
+            if (userChange == 0) {
                 server->comm->client_id = ALT_CLIENT_ID;
-            else if (userChange == 1)
+                server->comm->expected_client_id = ALT_CLIENT_ID;
+            }
+            else if (userChange == 1) {
                 server->comm->client_id = WH_TEST_DEFAULT_CLIENT_ID;
+                server->comm->expected_client_id = WH_TEST_DEFAULT_CLIENT_ID;
+            }
             userChange++;
             am_connected = WH_COMM_CONNECTED;
             WH_TEST_RETURN_ON_FAIL(wh_Server_SetConnected(server, am_connected));
@@ -5865,6 +5869,7 @@ static int wh_ClientServer_MemThreadTest(whTestNvmBackendType nvmType)
                  .transport_context = (void*)tmsc,
                  .transport_config  = (void*)tmcf,
                  .server_id         = 124,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
 
     /* RamSim Flash state and configuration */

test/wh_test_log.c

@@ -1466,6 +1466,7 @@ static int whTest_LogClientServerMemTransport(void)
                  .transport_context = (void*)tmsc,
                  .transport_config  = (void*)tmcf,
                  .server_id         = 124,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
 
     uint8_t          memory[WH_LOG_TEST_FLASH_RAM_SIZE] = {0};

test/wh_test_multiclient.c

@@ -1514,6 +1514,7 @@ static int whTest_MultiClientSequential(void)
                  .transport_context = (void*)tmsc1,
                  .transport_config  = (void*)tmcf1,
                  .server_id         = 101,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
     whServerConfig              s_conf1[1]  = {{
                       .comm_config = cs_conf1,
@@ -1532,6 +1533,7 @@ static int whTest_MultiClientSequential(void)
                  .transport_context = (void*)tmsc2,
                  .transport_config  = (void*)tmcf2,
                  .server_id         = 102,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID + 1,
     }};
     whServerConfig              s_conf2[1]  = {{
                       .comm_config = cs_conf2,

test/wh_test_posix_threadsafe_stress.c

@@ -640,6 +640,7 @@ static int initClientServerPair(StressTestContext* ctx, int pairIndex)
     pair->serverCommConfig.transport_context = &pair->serverTransportCtx;
     pair->serverCommConfig.transport_config  = &pair->tmConfig;
     pair->serverCommConfig.server_id         = (uint16_t)(200 + pairIndex);
+    pair->serverCommConfig.client_id         = (uint8_t)(100 + pairIndex);
 
     /* Configure crypto context */
     pair->cryptoCtx.devId = INVALID_DEVID;

test/wh_test_server_img_mgr.c

@@ -1215,6 +1215,7 @@ int whTest_ServerImgMgr(whTestNvmBackendType nvmType)
                  .transport_context = (void*)tmsc,
                  .transport_config  = (void*)tmcf,
                  .server_id         = 124,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
 
     /* RamSim Flash state and configuration */

test/wh_test_she.c

@@ -532,6 +532,7 @@ static int wh_ClientServer_MemThreadTest(void)
                  .transport_context = (void*)tmsc,
                  .transport_config  = (void*)tmcf,
                  .server_id         = 124,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
 
     /* RamSim Flash state and configuration */

test/wh_test_wolfcrypt_test.c

@@ -209,6 +209,7 @@ static int wh_ClientServer_MemThreadTest(void)
                  .transport_context = (void*)tmsc,
                  .transport_config  = (void*)tmcf,
                  .server_id         = 124,
+                 .client_id         = WH_TEST_DEFAULT_CLIENT_ID,
     }};
 
     /* RamSim Flash state and configuration */

tools/whnvmtool/test/test_whnvmtool.c

@@ -53,6 +53,7 @@ whCommServerConfig gCommServerConfig[1] = {{
     .transport_context = (void*)gTransportServerContext,
     .transport_config  = (void*)gTransportTcpConfig,
     .server_id         = 34,
+    .client_id         = 1,
 }};
 
 

tools/whnvmtool/whnvmtool.c

@@ -528,6 +528,7 @@ int main(int argc, char* argv[])
         .transport_context = (void*)gTransportServerContext,
         .transport_config  = (void*)gTransportTcpConfig,
         .server_id         = 34,
+        .client_id         = 1,
     }};
 
     /* POSIX flash file NVM configuration */

wolfhsm/wh_comm.h

@@ -253,7 +253,8 @@ typedef struct {
     const whTransportServerCb* transport_cb;
     const void* transport_config;
     uint8_t server_id;
-    uint8_t WH_PAD[7];
+    uint8_t client_id;
+    uint8_t WH_PAD[6];
 } whCommServerConfig;
 
 /* Context structure for a server.  Note the client context will track the
@@ -270,6 +271,8 @@ typedef struct {
     uint16_t reqid;
     uint8_t client_id;
     uint8_t server_id;
+    uint8_t expected_client_id;
+    uint8_t WH_PAD[7];
 } whCommServer;
 
 /* Reset the state of the server context and begin the connection to a client