commit 90bc6b814334b1352bf057b056e4024dc6239021
author Jaeden Amero <jaeden.amero@arm.com> Tue Nov 12 10:38:20 2019 +0000
committer GitHub <noreply@github.com> Tue Nov 12 10:38:20 2019 +0000
tree 70f727ecfe10abefc86b48c884b5ce58fdb59bb2
parent 95b9f601fd04503033a2a7eb14e18e3f29f9007d
parent 96ae5cd08707eedb51e555f0b347a228c5d62519

Merge pull request #281 from AndrzejKurek/IOTCRYPT-968-zeroize-aes-variables

Zeroize local AES variables before exiting the function

library/aes.c

diff --git a/library/aes.c b/library/aes.c
index aff0a99..02a7986 100644
--- a/library/aes.c
+++ b/library/aes.c
@@ -918,6 +918,18 @@
     PUT_UINT32_LE( X2, output,  8 );
     PUT_UINT32_LE( X3, output, 12 );
 
+    mbedtls_platform_zeroize( &X0, sizeof( X0 ) );
+    mbedtls_platform_zeroize( &X1, sizeof( X1 ) );
+    mbedtls_platform_zeroize( &X2, sizeof( X2 ) );
+    mbedtls_platform_zeroize( &X3, sizeof( X3 ) );
+
+    mbedtls_platform_zeroize( &Y0, sizeof( Y0 ) );
+    mbedtls_platform_zeroize( &Y1, sizeof( Y1 ) );
+    mbedtls_platform_zeroize( &Y2, sizeof( Y2 ) );
+    mbedtls_platform_zeroize( &Y3, sizeof( Y3 ) );
+
+    mbedtls_platform_zeroize( &RK, sizeof( RK ) );
+
     return( 0 );
 }
 #endif /* !MBEDTLS_AES_ENCRYPT_ALT */
@@ -986,6 +998,18 @@
     PUT_UINT32_LE( X2, output,  8 );
     PUT_UINT32_LE( X3, output, 12 );
 
+    mbedtls_platform_zeroize( &X0, sizeof( X0 ) );
+    mbedtls_platform_zeroize( &X1, sizeof( X1 ) );
+    mbedtls_platform_zeroize( &X2, sizeof( X2 ) );
+    mbedtls_platform_zeroize( &X3, sizeof( X3 ) );
+
+    mbedtls_platform_zeroize( &Y0, sizeof( Y0 ) );
+    mbedtls_platform_zeroize( &Y1, sizeof( Y1 ) );
+    mbedtls_platform_zeroize( &Y2, sizeof( Y2 ) );
+    mbedtls_platform_zeroize( &Y3, sizeof( Y3 ) );
+
+    mbedtls_platform_zeroize( &RK, sizeof( RK ) );
+
     return( 0 );
 }
 #endif /* !MBEDTLS_AES_DECRYPT_ALT */