Ensure mbedtls_sha3_finish zeroizes the context
Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/library/sha3.c b/library/sha3.c
index 4b97a85..9825504 100644
--- a/library/sha3.c
+++ b/library/sha3.c
@@ -259,10 +259,13 @@
int mbedtls_sha3_finish(mbedtls_sha3_context *ctx,
uint8_t *output, size_t olen)
{
+ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+
/* Catch SHA-3 families, with fixed output length */
if (ctx->olen > 0) {
if (ctx->olen > olen) {
- return MBEDTLS_ERR_SHA3_BAD_INPUT_DATA;
+ ret = MBEDTLS_ERR_SHA3_BAD_INPUT_DATA;
+ goto exit;
}
olen = ctx->olen;
}
@@ -280,7 +283,11 @@
}
}
- return 0;
+ ret = 0;
+
+exit:
+ mbedtls_platform_zeroize(ctx, sizeof(mbedtls_sha3_context));
+ return ret;
}
/*
diff --git a/tests/suites/test_suite_shax.function b/tests/suites/test_suite_shax.function
index 7dd9166..629e281 100644
--- a/tests/suites/test_suite_shax.function
+++ b/tests/suites/test_suite_shax.function
@@ -176,9 +176,12 @@
TEST_EQUAL(mbedtls_sha3_starts(&ctx, MBEDTLS_SHA3_NONE), MBEDTLS_ERR_SHA3_BAD_INPUT_DATA);
TEST_EQUAL(mbedtls_sha3_starts(&ctx, MBEDTLS_SHA3_256), 0);
-
TEST_EQUAL(mbedtls_sha3_finish(&ctx, output, 0), MBEDTLS_ERR_SHA3_BAD_INPUT_DATA);
+
+ TEST_EQUAL(mbedtls_sha3_starts(&ctx, MBEDTLS_SHA3_256), 0);
TEST_EQUAL(mbedtls_sha3_finish(&ctx, output, 31), MBEDTLS_ERR_SHA3_BAD_INPUT_DATA);
+
+ TEST_EQUAL(mbedtls_sha3_starts(&ctx, MBEDTLS_SHA3_256), 0);
TEST_EQUAL(mbedtls_sha3_finish(&ctx, output, 32), 0);
exit: