commit 73cfde8f85e10f4face574ee783904b33e6d0c62
author Thomas Daubney <thomas.daubney@arm.com> Tue May 30 15:34:28 2023 +0100
committer Thomas Daubney <thomas.daubney@arm.com> Thu Jun 01 13:05:28 2023 +0100
tree 0df638939d22be7ca6388b07db2a576657d060c1
parent cd33413a55aad3cf7ed68427dfa98cf25beaf35b

Remove certain null pointer checks when only MD_LIGHT enabled

When MD_LIGHT is enabled but MD_C is not then certain null
pointer checks can be removed on functions that take an
mbedtls_md_context_t * as a parameter, since MD_LIGHT does
not support these null pointers.

Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>

library/md.c

diff --git a/library/md.c b/library/md.c
index bebe358..306af72 100644
--- a/library/md.c
+++ b/library/md.c
@@ -376,7 +376,12 @@
 
 int mbedtls_md_setup(mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info, int hmac)
 {
-    if (md_info == NULL || ctx == NULL) {
+#if defined(MBEDTLS_MD_C)
+    if (ctx == NULL) {
+        return MBEDTLS_ERR_MD_BAD_INPUT_DATA;
+    }
+#endif
+    if (md_info == NULL) {
         return MBEDTLS_ERR_MD_BAD_INPUT_DATA;
     }
 
@@ -455,9 +460,11 @@
 
 int mbedtls_md_starts(mbedtls_md_context_t *ctx)
 {
+#if defined(MBEDTLS_MD_C)
     if (ctx == NULL || ctx->md_info == NULL) {
         return MBEDTLS_ERR_MD_BAD_INPUT_DATA;
     }
+#endif
 
 #if defined(MBEDTLS_MD_SOME_PSA)
     if (ctx->engine == MBEDTLS_MD_ENGINE_PSA) {
@@ -504,9 +511,11 @@
 
 int mbedtls_md_update(mbedtls_md_context_t *ctx, const unsigned char *input, size_t ilen)
 {
+#if defined(MBEDTLS_MD_C)
     if (ctx == NULL || ctx->md_info == NULL) {
         return MBEDTLS_ERR_MD_BAD_INPUT_DATA;
     }
+#endif
 
 #if defined(MBEDTLS_MD_SOME_PSA)
     if (ctx->engine == MBEDTLS_MD_ENGINE_PSA) {
@@ -551,9 +560,11 @@
 
 int mbedtls_md_finish(mbedtls_md_context_t *ctx, unsigned char *output)
 {
+#if defined(MBEDTLS_MD_C)
     if (ctx == NULL || ctx->md_info == NULL) {
         return MBEDTLS_ERR_MD_BAD_INPUT_DATA;
     }
+#endif
 
 #if defined(MBEDTLS_MD_SOME_PSA)
     if (ctx->engine == MBEDTLS_MD_ENGINE_PSA) {