From: Tobias Brunner <tobias@strongswan.org>
Date: Thu, 11 Feb 2021 16:09:04 +0000 (+0100)
Subject: tls-crypto: Don't filter suites with specific ECDH group if any is available
X-Git-Tag: 5.9.2rc1~23^2~4
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=311405c34d5a943f4b302c5ef13727a15e23d93f;p=thirdparty%2Fstrongswan.git

tls-crypto: Don't filter suites with specific ECDH group if any is available

Since DH groups (or with TLS < 1.3 curves) are negotiated separately,
it doesn't matter which one is listed in the cipher suite as any one could
be used.
---

diff --git a/src/libtls/tls_crypto.c b/src/libtls/tls_crypto.c
index 07d5ce7146..d7faa4e253 100644
--- a/src/libtls/tls_crypto.c
+++ b/src/libtls/tls_crypto.c
@@ -837,8 +837,10 @@ static void filter_suite(suite_algs_t suites[], int *count, int offset,
 			}
 			if (current.dh && current.dh != suites[i].dh)
 			{
-				if (suites[i].dh != MODP_NONE)
-				{	/* skip DH group, does not match nor NONE */
+				if (suites[i].dh != MODP_NONE &&
+					!(diffie_hellman_group_is_ec(current.dh) &&
+					  diffie_hellman_group_is_ec(suites[i].dh)))
+				{	/* skip DH group, does not match nor NONE nor both ECDH */
 					continue;
 				}
 			}