Add TBS context that persists across commands

src/tpm2.c

@@ -39,12 +39,16 @@ static volatile int gWolfCryptRefCount = 0;
 
 #ifdef WOLFTPM_LINUX_DEV
 #define INTERNAL_SEND_COMMAND      TPM2_LINUX_SendCommand
+#define TPM2_INTERNAL_CLEANUP(ctx)
 #elif defined(WOLFTPM_SWTPM)
 #define INTERNAL_SEND_COMMAND      TPM2_SWTPM_SendCommand
+#define TPM2_INTERNAL_CLEANUP(ctx)
 #elif defined(WOLFTPM_WINAPI)
 #define INTERNAL_SEND_COMMAND      TPM2_WinApi_SendCommand
+#define TPM2_INTERNAL_CLEANUP(ctx) TPM2_WinApi_Cleanup(ctx)
 #else
 #define INTERNAL_SEND_COMMAND      TPM2_TIS_SendCommand
+#define TPM2_INTERNAL_CLEANUP(ctx)
 #endif
 
 /******************************************************************************/
@@ -387,6 +391,7 @@ TPM_RC TPM2_Cleanup(TPM2_CTX* ctx)
     if (rc == TPM_RC_SUCCESS) {
 
         if (TPM2_GetActiveCtx() == ctx) {
+            TPM2_INTERNAL_CLEANUP(ctx);
             /* set non-active */
             TPM2_SetActiveCtx(NULL);
         }

src/tpm2_winapi.c

@@ -60,7 +60,6 @@ typedef const TBS_CONTEXT_PARAMS2 *PCTBS_CONTEXT_PARAMS2;
 /* Talk to a TPM device using Windows TBS */
 int TPM2_WinApi_SendCommand(TPM2_CTX* ctx, TPM2_Packet* packet)
 {
-    TBS_HCONTEXT tbs_context;
     TBS_CONTEXT_PARAMS2 tbs_params;
     tbs_params.version = TBS_CONTEXT_VERSION_TWO;
     tbs_params.includeTpm12 = 0;
@@ -68,12 +67,11 @@ int TPM2_WinApi_SendCommand(TPM2_CTX* ctx, TPM2_Packet* packet)
 
     int rc = 0;
 
-    (void)ctx;
+    /* open, if not already open */
 
-    /* open on first transmit */
+    if (ctx->winCtx.tbs_context == NULL) {
-    if (rc == 0) {
         rc = Tbsi_Context_Create((TBS_CONTEXT_PARAMS*)&tbs_params,
-                                 &tbs_context);
+                                 &ctx->winCtx.tbs_context);
         printf("create rc: %d\n", rc);
     }
 
@@ -82,7 +80,7 @@ int TPM2_WinApi_SendCommand(TPM2_CTX* ctx, TPM2_Packet* packet)
         uint32_t tmp = packet->size;
         printf("tx:\n");
         TPM2_PrintBin(packet->buf, packet->pos);
-	rc = Tbsip_Submit_Command(tbs_context,
+	rc = Tbsip_Submit_Command(ctx->winCtx.tbs_context,
 				  TBS_COMMAND_LOCALITY_ZERO,
 				  TBS_COMMAND_PRIORITY_NORMAL,
 				  packet->buf,
@@ -96,7 +94,17 @@ int TPM2_WinApi_SendCommand(TPM2_CTX* ctx, TPM2_Packet* packet)
     if (rc == 0) {
         printf("rx:\n");
         TPM2_PrintBin(packet->buf, packet->pos);
-        rc = Tbsip_Context_Close(tbs_context);
+    }
+
+    return rc;
+}
+
+int TPM2_WinApi_Cleanup(TPM2_CTX* ctx)
+{
+    int rc = TPM_RC_SUCCESS;
+    if (ctx->winCtx.tbs_context != NULL) {
+        rc = Tbsip_Context_Close(ctx->winCtx.tbs_context);
+        ctx->winCtx.tbs_context = NULL;
         printf("close rc: %d\n", rc);
     }
 

wolftpm/tpm2.h

@@ -1613,12 +1613,21 @@ static const BYTE TPM_20_EK_AUTH_POLICY[] = {
 
 /* HAL IO Callbacks */
 struct TPM2_CTX;
+
 #ifdef WOLFTPM_SWTPM
 struct wolfTPM_tcpContext {
     int fd;
 };
 #endif /* WOLFTPM_SWTPM */
 
+#ifdef WOLFTPM_WINAPI
+#include <tbs.h>
+
+struct wolfTPM_winContext {
+  TBS_HCONTEXT tbs_context;
+};
+#endif /* WOLFTPM_SWTPM */
+
 /* make sure advanced IO is enabled for I2C */
 #ifdef WOLFTPM_I2C
     #undef  WOLFTPM_ADV_IO
@@ -1644,6 +1653,9 @@ typedef struct TPM2_CTX {
 #ifdef WOLFTPM_SWTPM
     struct wolfTPM_tcpContext tcpCtx;
 #endif
+#ifdef WOLFTPM_WINAPI
+    struct wolfTPM_winContext winCtx;
+#endif
 #ifndef WOLFTPM2_NO_WOLFCRYPT
 #ifndef SINGLE_THREADED
     wolfSSL_Mutex hwLock;

wolftpm/tpm2_winapi.h

@@ -32,6 +32,9 @@
 /* TPM2 IO for using TPM through the Winapi kernel driver */
 WOLFTPM_LOCAL int TPM2_WinApi_SendCommand(TPM2_CTX* ctx, TPM2_Packet* packet);
 
+/* Cleanup winpi context */
+WOLFTPM_LOCAL int TPM2_WinApi_Cleanup(TPM2_CTX* ctx);
+
 #ifdef __cplusplus
     }  /* extern "C" */
 #endif