Add mbedtls_ssl_cf_memcpy_offset() with tests
The tests are supposed to be failing now (in all.sh component
test_memsan_constant_flow), but they don't as apparently MemSan doesn't
complain when the src argument of memcpy() is uninitialized, see
https://github.com/google/sanitizers/issues/1296
The next commit will add an option to test constant flow with valgrind, which
will hopefully correctly flag the current non-constant-flow implementation.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/tests/suites/test_suite_ssl.data b/tests/suites/test_suite_ssl.data
index 3afa39a..1b79191 100644
--- a/tests/suites/test_suite_ssl.data
+++ b/tests/suites/test_suite_ssl.data
@@ -10545,3 +10545,15 @@
Constant-flow HMAC: SHA384
depends_on:MBEDTLS_SHA512_C:!MBEDTLS_SHA512_NO_SHA384
ssl_cf_hmac:MBEDTLS_MD_SHA384
+
+# these are the numbers we'd get with an empty plaintext and truncated HMAC
+Constant-flow memcpy from offset: small
+ssl_cf_memcpy_offset:0:5:10
+
+# we could get this with 255-bytes plaintext and untruncated SHA-256
+Constant-flow memcpy from offset: medium
+ssl_cf_memcpy_offset:0:255:32
+
+# we could get this with 255-bytes plaintext and untruncated SHA-384
+Constant-flow memcpy from offset: large
+ssl_cf_memcpy_offset:100:339:48
diff --git a/tests/suites/test_suite_ssl.function b/tests/suites/test_suite_ssl.function
index f7c9be0..7c4f865 100644
--- a/tests/suites/test_suite_ssl.function
+++ b/tests/suites/test_suite_ssl.function
@@ -4361,3 +4361,36 @@
mbedtls_free( out );
}
/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_SSL_SOME_SUITES_USE_TLS_CBC:MBEDTLS_TEST_HOOKS */
+void ssl_cf_memcpy_offset( int offset_min, int offset_max, int len )
+{
+ unsigned char *dst = NULL;
+ unsigned char *src = NULL;
+ size_t src_len = offset_max + len;
+ size_t secret;
+
+ ASSERT_ALLOC( dst, len );
+ ASSERT_ALLOC( src, src_len );
+
+ /* Fill src in a way that we can detect if we copied the right bytes */
+ mbedtls_test_rnd_std_rand( NULL, src, src_len );
+
+ for( secret = offset_min; secret <= (size_t) offset_max; secret++ )
+ {
+ test_set_step( (int) secret );
+
+ TEST_CF_SECRET( &secret, sizeof( secret ) );
+ mbedtls_ssl_cf_memcpy_offset( dst, src, secret,
+ offset_min, offset_max, len );
+ TEST_CF_PUBLIC( &secret, sizeof( secret ) );
+ TEST_CF_PUBLIC( dst, len );
+
+ ASSERT_COMPARE( dst, len, src + secret, len );
+ }
+
+exit:
+ mbedtls_free( dst );
+ mbedtls_free( src );
+}
+/* END_CASE */