This issue has been reported by Tuba Yavuz, Farhaan Fowze, Ken (Yihang) Bai,
Grant Hernandez, and Kevin Butler (University of Florida) and
Dave Tian (Purdue University).
In AES encrypt and decrypt some variables were left on the stack. The value
of these variables can be used to recover the last round key. To follow best
practice and to limit the impact of buffer overread vulnerabilities (like
Heartbleed) we need to zeroize them before exiting the function.
Add missing MBEDTLS_DEPRECATED_REMOVED guards around the definitions
of mbedtls_aes_decrypt and mbedtls_aes_encrypt.
This fixes the build under -Wmissing-prototypes -Werror.
Fixes#1388
The commit f5bf7189d303e602992c750c09e429e23c7b2abf made the AES
functions mbedtls_aes_encrypt and mbedtls_aes_decrypt static, changing
the library's API.
This commit reverts this.
This patch modifies the function mbedtls_aes_selftest() function to
ensure that AES-192 tests are only run if the key size is supported by
the available implementation. This is useful when using MBEDTLS_AES_ALT
as some hardware crypto accelerators might not support AES-192.
This patch modifies the following 2 functions in the AES module to
change the return type from void to int:
* mbedtls_aes_encrypt() -> mbedtls_internal_aes_encrypt()
* mbedtls_aes_decrypt() -> mbedtls_internal_aes_decrypt()
This change is necessary to allow users of MBEDTLS_AES_ALT,
MBEDTLS_AES_DECRYPT_ALT and MBEDTLS_AES_ENCRYPT_ALT to return an error
code when replacing the default with their own implementation, e.g.
a hardware crypto accelerator.
This commit fixes following warning:
> CC: aes.c
> aes.c: In function 'mbedtls_aes_self_test':
> aes.c:1225:19: error: unused variable 'iv' [-Werror=unused-variable]
> unsigned char iv[16];
> ^
> cc1: all warnings being treated as errors
All symmetric cipher algorithms and hash algorithms now include support
for a POLARSSL_XXX_ALT flag that prevents the definition of the
algorithm context structure and all 'core' functions.
(cherry picked from commit 4087c47043cb7b8b51e69f1de47ab6a2bccead3d)