From 580d1f49544003972d2786c1ed1217bdf59baf42 Mon Sep 17 00:00:00 2001
From: Gilles Peskine <Gilles.Peskine@arm.com>
Date: Fri, 8 Aug 2025 00:06:06 +0200
Subject: [PATCH] Do dedicated constant-time testing in a few more
 configurations

Do constant-time testing in a couple of configurations that give some
interesting coverage;

* In a configuration that's close to the default: `test_aes_only_128_bit_keys`.
  Having only 128-bit AES keys doesn't reduce the interesting scope much
  (except that it doesn't test 192-bit and 256-bit AES, but since that
  configuration uses hardware AES, we don't care about that part).
* when PSA buffer copying is not done, i.e. when
  `MBEDTLS_PSA_ASSUME_EXCLUSIVE_BUFFERS` is enabled. This will be very
  relevant for the upcoming PSA constant-time tests.

Use Valgrind, since some of the interesting tests require constant-time AES,
which for us means AESNI or AESCE, which MSan doesn't support.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
---
 .../components-configuration-crypto.sh        | 37 +++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/tests/scripts/components-configuration-crypto.sh b/tests/scripts/components-configuration-crypto.sh
index 04c38f6c36..6b12bb9af5 100644
--- a/tests/scripts/components-configuration-crypto.sh
+++ b/tests/scripts/components-configuration-crypto.sh
@@ -5,6 +5,28 @@
 
 # This file contains test components that are executed by all.sh
 
+## test_with_valgrind tests/suites/SUITE.data [...]
+## Run the specified test suite(s) with Valgrind.
+test_with_valgrind () {
+    for data_file in "$@"; do
+        suite="${data_file##*/}"; suite="${suite%.data}"
+        exe="tests/$suite"
+        log_file="tests/MemoryChecker.$suite.log"
+        make -C tests "$suite"
+        valgrind -q --tool=memcheck --track-origins=yes --log-file="$log_file" "$exe"
+        not grep . -- "$log_file"
+    done
+}
+
+## Run a small set of dedicated constant-time tests with Valgrind.
+## Exclude very slow suites.
+## Exclude suites that contain some constant-time tests, but whose focus
+## isn't on constant-time tests.
+test_with_valgrind_constant_time () {
+    declare GLOBIGNORE="tests/suites/test_suite_constant_time_hmac.data"
+    test_with_valgrind tests/suites/*constant_time*.data
+}
+
 ################################################################
 #### Configuration Testing - Crypto
 ################################################################
@@ -31,6 +53,17 @@ component_test_psa_assume_exclusive_buffers () {
     make test
 }
 
+component_test_psa_assume_exclusive_buffers_valgrind_cf () {
+    msg "build: full config + MBEDTLS_PSA_ASSUME_EXCLUSIVE_BUFFERS, constant flow with Valgrind"
+    scripts/config.py full
+    scripts/config.py set MBEDTLS_PSA_ASSUME_EXCLUSIVE_BUFFERS
+    scripts/config.py set MBEDTLS_TEST_CONSTANT_FLOW_VALGRIND
+    make lib
+
+    msg "test: full config + MBEDTLS_PSA_ASSUME_EXCLUSIVE_BUFFERS, constant flow with Valgrind, selected suites"
+    test_with_valgrind_constant_time tests/suites/*constant_time*.data
+}
+
 component_test_crypto_with_static_key_slots() {
     msg "build: crypto full + MBEDTLS_PSA_STATIC_KEY_SLOTS"
     scripts/config.py crypto_full
@@ -2969,11 +3002,15 @@ component_test_aes_only_128_bit_keys () {
     msg "build: default config + AES_ONLY_128_BIT_KEY_LENGTH"
     scripts/config.py set MBEDTLS_AES_ONLY_128_BIT_KEY_LENGTH
     scripts/config.py unset MBEDTLS_PADLOCK_C
+    scripts/config.py set MBEDTLS_TEST_CONSTANT_FLOW_VALGRIND
 
     make CFLAGS='-O2 -Werror -Wall -Wextra'
 
     msg "test: default config + AES_ONLY_128_BIT_KEY_LENGTH"
     make test
+
+    msg "test: default config + AES_ONLY_128_BIT_KEY_LENGTH constant flow with Valgrind, selected suites"
+    test_with_valgrind_constant_time
 }
 
 component_test_no_ctr_drbg_aes_only_128_bit_keys () {