commit 24eed8d2d2df4423a63c8761edd0d65a43ff03a3
author Janos Follath <janos.follath@arm.com> Fri Nov 22 13:21:35 2019 +0000
committer Janos Follath <janos.follath@arm.com> Tue Dec 03 16:07:18 2019 +0000
tree fefff85746d2b1296b06cfca0ad6cfcd18aed758
parent a13b905d8dde4d851f1730e62643d1fb775649ca

Initialise return values to an error

Initialising the return values to and error is best practice and makes
the library more robust.

library/cipher.c

diff --git a/library/cipher.c b/library/cipher.c
index 69079aa..b62f1d5 100644
--- a/library/cipher.c
+++ b/library/cipher.c
@@ -34,6 +34,7 @@
 #include "mbedtls/cipher.h"
 #include "mbedtls/cipher_internal.h"
 #include "mbedtls/platform_util.h"
+#include "mbedtls/error.h"
 
 #include <stdlib.h>
 #include <string.h>
@@ -504,7 +505,7 @@
 int mbedtls_cipher_update( mbedtls_cipher_context_t *ctx, const unsigned char *input,
                    size_t ilen, unsigned char *output, size_t *olen )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t block_size;
 
     CIPHER_VALIDATE_RET( ctx != NULL );
@@ -1134,7 +1135,7 @@
                       const unsigned char *tag, size_t tag_len )
 {
     unsigned char check_tag[16];
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
     CIPHER_VALIDATE_RET( ctx != NULL );
     CIPHER_VALIDATE_RET( tag_len == 0 || tag != NULL );
@@ -1211,7 +1212,7 @@
                   const unsigned char *input, size_t ilen,
                   unsigned char *output, size_t *olen )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t finish_olen;
 
     CIPHER_VALIDATE_RET( ctx != NULL );
@@ -1455,7 +1456,7 @@
 #if defined(MBEDTLS_GCM_C)
     if( MBEDTLS_MODE_GCM == ctx->cipher_info->mode )
     {
-        int ret;
+        int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
         *olen = ilen;
         ret = mbedtls_gcm_auth_decrypt( ctx->cipher_ctx, ilen,
@@ -1471,7 +1472,7 @@
 #if defined(MBEDTLS_CCM_C)
     if( MBEDTLS_MODE_CCM == ctx->cipher_info->mode )
     {
-        int ret;
+        int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
         *olen = ilen;
         ret = mbedtls_ccm_auth_decrypt( ctx->cipher_ctx, ilen,
@@ -1487,7 +1488,7 @@
 #if defined(MBEDTLS_CHACHAPOLY_C)
     if ( MBEDTLS_CIPHER_CHACHA20_POLY1305 == ctx->cipher_info->type )
     {
-        int ret;
+        int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
         /* ChachaPoly has fixed length nonce and MAC (tag) */
         if ( ( iv_len != ctx->cipher_info->iv_size ) ||