From 4769d136d9a72ca90fa5e38213cb49d7f415313d Mon Sep 17 00:00:00 2001
From: Michael Rash <mbr@cipherdyne.org>
Date: Sun, 19 Aug 2018 16:19:56 -0700
Subject: [PATCH] [libfko] add NULL check to fko_get_raw_spa_digest_type() -
 bug discovered by fko-wrapper

---
 lib/fko.h        | 3 ++-
 lib/fko_digest.c | 3 +++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/fko.h b/lib/fko.h
index 6c7d01bd..32808258 100644
--- a/lib/fko.h
+++ b/lib/fko.h
@@ -649,8 +649,8 @@ DLL_API int fko_set_spa_encryption_mode(fko_ctx_t ctx, const int encrypt_mode);
  * \return FKO_SUCCESS if successful, returns an error code otherwise
  */
 DLL_API int fko_set_spa_data(fko_ctx_t ctx, const char * const enc_msg);
-#if AFL_FUZZING
 
+#if AFL_FUZZING
 DLL_API int fko_afl_set_spa_data(fko_ctx_t ctx, const char * const enc_msg,
         const int enc_msg_len);
 #endif
@@ -856,6 +856,7 @@ DLL_API int fko_get_spa_hmac(fko_ctx_t ctx, char **enc_data);
  * \return FKO_SUCCESS if successful, returns an error code otherwise
  */
 DLL_API int fko_get_encoded_data(fko_ctx_t ctx, char **enc_data);
+
 #if FUZZING_INTERFACES
 DLL_API int fko_set_encoded_data(fko_ctx_t ctx, const char * const encoded_msg,
         const int msg_len, const int do_digest, const int digest_type);
diff --git a/lib/fko_digest.c b/lib/fko_digest.c
index 7994a9d1..0c543e68 100644
--- a/lib/fko_digest.c
+++ b/lib/fko_digest.c
@@ -114,6 +114,9 @@ fko_get_raw_spa_digest_type(fko_ctx_t ctx, short *raw_digest_type)
     if(!CTX_INITIALIZED(ctx))
         return(FKO_ERROR_CTX_NOT_INITIALIZED);
 
+    if(raw_digest_type == NULL)
+        return(FKO_ERROR_INVALID_DATA);
+
     *raw_digest_type = ctx->raw_digest_type;
 
     return(FKO_SUCCESS);