add X25519MLKEM768 to the start of the default ECDHE curves list, allowing

libtls clients to connect to servers which don't offer any other curves
(this has been seen in the wild with got, reported by stsp).  ok tb@

depends on recent libssl changes (ssl_tlsext.c r1.161, t1_lib.c r1.209).

2 files changed, 6 insertions, 6 deletions

diff --git a/src/lib/libtls/man/tls_config_set_protocols.3 b/src/lib/libtls/man/tls_config_set_protocols.3
index 403bc10b82..b9ef27ee6a 100644
--- a/src/lib/libtls/man/tls_config_set_protocols.3
+++ b/src/lib/libtls/man/tls_config_set_protocols.3
@@ -1,4 +1,4 @@
-.\" $OpenBSD: tls_config_set_protocols.3,v 1.13 2025/07/07 10:54:00 schwarze Exp $
+.\" $OpenBSD: tls_config_set_protocols.3,v 1.14 2026/06/06 16:23:30 sthen Exp $
 .\"
 .\" Copyright (c) 2014 Ted Unangst <tedu@openbsd.org>
 .\" Copyright (c) 2015, 2016 Joel Sing <jsing@openbsd.org>
@@ -16,7 +16,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: July 7 2025 $
+.Dd $Mdocdate: June 6 2026 $
 .Dt TLS_CONFIG_SET_PROTOCOLS 3
 .Os
 .Sh NAME
@@ -174,8 +174,8 @@ which disables DHE key exchange.
 specifies the names of the elliptic curves that may be used during Elliptic
 Curve Diffie-Hellman Ephemeral (ECDHE) key exchange.
 This is a comma separated list, given in order of preference.
-The special value of "default" will use the default curves (currently X25519,
-P-256 and P-384).
+The special value of "default" will use the default curves (currently
+X25519MLKEM768, X25519, P-256 and P-384).
 This function replaces
 .Fn tls_config_set_ecdhecurve ,
 which is deprecated.
diff --git a/src/lib/libtls/tls_internal.h b/src/lib/libtls/tls_internal.h
index 8e566a34e0..434efc196a 100644
--- a/src/lib/libtls/tls_internal.h
+++ b/src/lib/libtls/tls_internal.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: tls_internal.h,v 1.86 2024/12/10 08:40:30 tb Exp $ */
+/* $OpenBSD: tls_internal.h,v 1.87 2026/06/06 16:23:30 sthen Exp $ */
 /*
  * Copyright (c) 2014 Jeremie Courreges-Anglas <jca@openbsd.org>
  * Copyright (c) 2014 Joel Sing <jsing@openbsd.org>
@@ -37,7 +37,7 @@ __BEGIN_HIDDEN_DECLS
 #define TLS_CIPHERS_LEGACY      "HIGH:MEDIUM:!aNULL"
 #define TLS_CIPHERS_ALL         "ALL:!aNULL:!eNULL"
 
-#define TLS_ECDHE_CURVES        "X25519,P-256,P-384"
+#define TLS_ECDHE_CURVES        "X25519MLKEM768,X25519,P-256,P-384"
 
 union tls_addr {
         struct in_addr ip4;