Diff: targets/hal/TARGET_NUVOTON/TARGET_NUC472/entropy_hardware_poll.c

Revision:

144:ef7eb2e8f9f7

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/hal/TARGET_NUVOTON/TARGET_NUC472/entropy_hardware_poll.c	Fri Sep 02 15:07:44 2016 +0100
@@ -0,0 +1,116 @@
+/*
+ *  Hardware entropy collector for NUC472's RNGA
+ *
+ *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ */
+
+
+#include <stdlib.h>
+#include <string.h>
+#include "cmsis.h"
+#include "NUC472_442.h"
+#include "us_ticker_api.h"
+
+/*
+ * Get Random number generator.
+ */
+static volatile int  g_PRNG_done;
+
+void CRYPTO_IRQHandler()
+{
+    if (PRNG_GET_INT_FLAG()) {
+        g_PRNG_done = 1;
+        PRNG_CLR_INT_FLAG();
+    }
+} 
+
+static void rng_get(unsigned char *pConversionData)
+{
+	uint32_t *p32ConversionData;
+
+	p32ConversionData = (uint32_t *)pConversionData;
+	
+    /* Unlock protected registers */
+    SYS_UnlockReg();	
+    /* Enable IP clock */
+    CLK_EnableModuleClock(CRPT_MODULE);
+	
+    /* Lock protected registers */
+    SYS_LockReg();	
+	
+    NVIC_EnableIRQ(CRPT_IRQn);
+    PRNG_ENABLE_INT();
+	
+//	PRNG_Open(PRNG_KEY_SIZE_64, 0, 0);
+	PRNG_Open(PRNG_KEY_SIZE_256, 1, us_ticker_read());
+    PRNG_Start();
+    while (!g_PRNG_done);
+
+
+    PRNG_Read(p32ConversionData);
+
+//    printf("    0x%08x  0x%08x  0x%08x  0x%08x\n\r", *p32ConversionData, *(p32ConversionData+1), *(p32ConversionData+2), *(p32ConversionData+3));
+//    printf("    0x%08x  0x%08x  0x%08x  0x%08x\n\r", *(p32ConversionData+4), *(p32ConversionData+5), *(p32ConversionData+6), *(p32ConversionData+7));
+
+    PRNG_DISABLE_INT();
+    NVIC_DisableIRQ(CRPT_IRQn);
+//    CLK_DisableModuleClock(CRPT_MODULE);
+		
+}
+
+
+/*
+ * Get len bytes of entropy from the hardware RNG.
+ */
+ 
+int mbedtls_hardware_poll( void *data,
+                    unsigned char *output, size_t len, size_t *olen )
+{
+#if 0
+    unsigned long timer = us_ticker_read();
+    ((void) data);
+    *olen = 0;
+ 
+    if( len < sizeof(unsigned long) )
+        return( 0 );
+ 
+    memcpy( output, &timer, sizeof(unsigned long) );
+    *olen = sizeof(unsigned long);
+#else
+	*olen = 0;
+    if( len < 32 )
+	{
+		unsigned char tmpBuff[32];		
+		rng_get(tmpBuff);
+		memcpy( output, &tmpBuff, len );
+		*olen = len;
+        return( 0 );
+	}	
+	for( int i = 0; i < (len/32) ; i++)
+	{
+		rng_get(output);
+		*olen += 32;
+//		printf("Output result of len[%d][%d]: 0x%08x 0x%08x\n\r", len, *olen, *((int32_t *)output), *(((int32_t *)output)+1));
+		output += 32;
+	}
+#endif
+	
+    return( 0 );
+}
+ 
+
+