AuroraMiddleware/mbedtls
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

ssl: Don't access non-existent encrypt_then_mac field

Browse Source 
When MBEDTLS_SSL_ENCRYPT_THEN_MAC is enabled, but not
MBEDTLS_SSL_SOME_MODES_USE_MAC, mbedtls_ssl_derive_keys() and
build_transforms() will attempt to use a non-existent `encrypt_then_mac`
field in the ssl_transform.

    Compile [ 93.7%]: ssl_tls.c
    [Error] ssl_tls.c@865,14: 'mbedtls_ssl_transform {aka struct mbedtls_ssl_transform}' ha
s no member named 'encrypt_then_mac'
    [ERROR] ./mbed-os/features/mbedtls/src/ssl_tls.c: In function 'mbedtls_ssl_derive_keys'
:
    ./mbed-os/features/mbedtls/src/ssl_tls.c:865:14: error: 'mbedtls_ssl_transform {aka str
uct mbedtls_ssl_transform}' has no member named 'encrypt_then_mac'
         transform->encrypt_then_mac = session->encrypt_then_mac;
                  ^~

Change mbedtls_ssl_derive_keys() and build_transforms() to only access
`encrypt_then_mac` if `encrypt_then_mac` is actually present.

Add a regression test to detect when we have regressions with
configurations that do not include any MAC ciphersuites.

Fixes d56ed2491b ("Reduce size of `ssl_transform` if no MAC ciphersuite is enabled")
This commit is contained in:
Jaeden Amero 2019-06-05 13:32:08 +01:00
parent a1491fe74f
commit 2de07f1dd1
3 changed files with 18 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
library/ssl_tls.c
View File

@ -953,7 +953,8 @@ int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl )
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> derive keys" ) );
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) && \
defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
transform->encrypt_then_mac = session->encrypt_then_mac;
#endif
transform->minor_ver = ssl->minor_ver;

14
tests/scripts/all.sh
View File

@ -953,6 +953,20 @@ component_test_no_max_fragment_length_small_ssl_out_content_len () {
if_build_succeeded tests/ssl-opt.sh -f "Max fragment length\|Large buffer"
}
component_test_when_no_ciphersuites_have_mac () {
msg "build: when no ciphersuites have MAC"
scripts/config.pl unset MBEDTLS_CIPHER_NULL_CIPHER
scripts/config.pl unset MBEDTLS_ARC4_C
scripts/config.pl unset MBEDTLS_CIPHER_MODE_CBC
make
msg "test: !MBEDTLS_SSL_SOME_MODES_USE_MAC"
make test
msg "test ssl-opt.sh: !MBEDTLS_SSL_SOME_MODES_USE_MAC"
if_build_succeeded tests/ssl-opt.sh
}
component_test_null_entropy () {
msg "build: default config with MBEDTLS_TEST_NULL_ENTROPY (ASan build)"
scripts/config.pl set MBEDTLS_TEST_NULL_ENTROPY

3
tests/suites/test_suite_ssl.function
View File

@ -159,7 +159,8 @@ static int build_transforms( mbedtls_ssl_transform *t_in,
* Setup transforms
*/
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) && \
defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
t_out->encrypt_then_mac = etm;
t_in->encrypt_then_mac = etm;
#else