From 2984bd254317b2a2b660227d7e09c68ccf6d8d73 Mon Sep 17 00:00:00 2001
From: Hanno Becker <hanno.becker@arm.com>
Date: Tue, 26 Feb 2019 11:43:09 +0000
Subject: [PATCH] Add config sanity check for
 !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE

---
 include/mbedtls/check_config.h | 8 ++++++++
 include/mbedtls/ssl.h          | 7 +++++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/include/mbedtls/check_config.h b/include/mbedtls/check_config.h
index 00fb9b367..76ab07a9f 100644
--- a/include/mbedtls/check_config.h
+++ b/include/mbedtls/check_config.h
@@ -278,6 +278,14 @@
 #error "MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED defined, but not all prerequisites"
 #endif
 
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) &&        \
+    !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) &&              \
+    ( !defined(MBEDTLS_SHA256_C) &&                             \
+      !defined(MBEDTLS_SHA512_C) &&                             \
+      !defined(MBEDTLS_SHA1_C) )
+#error "!MBEDTLS_SSL_KEEP_PEER_CERTIFICATE requires MBEDTLS_SHA512_C, MBEDTLS_SHA256_C or MBEDTLS_SHA1_C"
+#endif
+
 #if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C) &&                          \
     ( !defined(MBEDTLS_PLATFORM_C) || !defined(MBEDTLS_PLATFORM_MEMORY) )
 #error "MBEDTLS_MEMORY_BUFFER_ALLOC_C defined, but not all prerequisites"
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 65c8d94d9..9a36009a7 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -812,7 +812,8 @@ typedef int mbedtls_ssl_async_resume_t( mbedtls_ssl_context *ssl,
 typedef void mbedtls_ssl_async_cancel_t( mbedtls_ssl_context *ssl );
 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
 
-#if defined(MBEDTLS_X509_CRT_PARSE_C)
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) &&        \
+    !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
 #define MBEDTLS_SSL_PEER_CERT_DIGEST_MAX_LEN  48
 #if defined(MBEDTLS_SHA256_C)
 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA256
@@ -824,9 +825,11 @@ typedef void mbedtls_ssl_async_cancel_t( mbedtls_ssl_context *ssl );
 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA1
 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN  20
 #else
+/* This is already checked in check_config.h, but be sure. */
 #error "Bad configuration - need SHA-1, SHA-256 or SHA-512 enabled to compute digest of peer CRT."
 #endif
-#endif /* MBEDTLS_X509_CRT_PARSE_C */
+#endif /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED &&
+          !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
 
 /*
  * This structure is used for storing current session data.