Change the default value of status variables to an error


Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/library/ccm.c b/library/ccm.c
index 9911e0f..750ec9e 100644
--- a/library/ccm.c
+++ b/library/ccm.c
@@ -37,6 +37,7 @@
 #if defined(MBEDTLS_CCM_C)
 
 #include "mbedtls/ccm.h"
+#include "mbedtls/platform.h"
 #include "mbedtls/platform_util.h"
 
 #include <string.h>
@@ -74,7 +75,7 @@
                         const unsigned char *key,
                         unsigned int keybits )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_PLATFORM_FAULT_DETECTED;
     const mbedtls_cipher_info_t *cipher_info;
 
     CCM_VALIDATE_RET( ctx != NULL );
@@ -98,7 +99,7 @@
         return( ret );
     }
 
-    return( 0 );
+    return( ret );
 }
 
 /*
@@ -155,7 +156,7 @@
                            const unsigned char *input, unsigned char *output,
                            unsigned char *tag, size_t tag_len )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_PLATFORM_FAULT_DETECTED;
     unsigned char i;
     unsigned char q;
     size_t len_left, olen;
@@ -315,7 +316,7 @@
     CTR_CRYPT( y, y, 16 );
     mbedtls_platform_memcpy( tag, y, tag_len );
 
-    return( 0 );
+    return( ret );
 }
 
 /*
@@ -365,7 +366,7 @@
                       const unsigned char *input, unsigned char *output,
                       const unsigned char *tag, size_t tag_len )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_PLATFORM_FAULT_DETECTED;
     unsigned char check_tag[16];
     unsigned char i;
     int diff;
@@ -394,7 +395,7 @@
         return( MBEDTLS_ERR_CCM_AUTH_FAILED );
     }
 
-    return( 0 );
+    return( ret );
 }
 
 int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,