From: Tobias Brunner <tobias@strongswan.org>
Date: Mon, 16 Aug 2021 08:50:01 +0000 (+0200)
Subject: openssl: Use a longer key to test/initialize HMAC instances
X-Git-Tag: 5.9.4dr1~3
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=64b281723c82c2345404fc7ac3fddf9bd2b155b6;p=thirdparty%2Fstrongswan.git

openssl: Use a longer key to test/initialize HMAC instances

OpenSSL enforces a minimum of 14 bytes (112 bits) on the key size when
used in FIPS-mode (as required by SP 800-131A).  So by using an empty
string, instantiation always failed.  32 bytes (256 bits) should be safe
for now.

Closes strongswan/strongswan#557
---

diff --git a/src/libstrongswan/plugins/openssl/openssl_hmac.c b/src/libstrongswan/plugins/openssl/openssl_hmac.c
index c4462fd3fd..f1a81919ce 100644
--- a/src/libstrongswan/plugins/openssl/openssl_hmac.c
+++ b/src/libstrongswan/plugins/openssl/openssl_hmac.c
@@ -100,8 +100,9 @@ METHOD(mac_t, set_key, bool,
 	private_mac_t *this, chunk_t key)
 {
 	if (!key.ptr)
-	{	/* HMAC_Init_ex() won't reset the key if a NULL pointer is passed */
-		key = chunk_from_str("");
+	{	/* HMAC_Init_ex() won't reset the key if a NULL pointer is passed,
+		 * use a lenghty string in case there is a limit in FIPS-mode */
+		key = chunk_from_str("00000000000000000000000000000000");
 	}
 	return reset(this, key);
 }
@@ -188,7 +189,7 @@ static mac_t *hmac_create(hash_algorithm_t algo)
 #endif
 
 	/* make sure the underlying hash algorithm is supported */
-	if (!set_key(this, chunk_from_str("")))
+	if (!set_key(this, chunk_empty))
 	{
 		destroy(this);
 		return NULL;