From ec20d7d79d702ab7bb49772cadbd3f2c6d1b5ec3 Mon Sep 17 00:00:00 2001
From: tb <tb@openbsd.org>
Date: Tue, 9 Jun 2026 05:20:38 +0000
Subject: [PATCH] ssl_kex: exercise an invalid point as well

---
 regress/lib/libssl/unit/ssl_kex.c | 35 ++++++++++++++++++++++++++++++-
 1 file changed, 34 insertions(+), 1 deletion(-)

diff --git a/regress/lib/libssl/unit/ssl_kex.c b/regress/lib/libssl/unit/ssl_kex.c
index 8b4f644a412..4050d04bd5f 100644
--- a/regress/lib/libssl/unit/ssl_kex.c
+++ b/regress/lib/libssl/unit/ssl_kex.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ssl_kex.c,v 1.3 2026/06/09 05:17:24 tb Exp $ */
+/*	$OpenBSD: ssl_kex.c,v 1.4 2026/06/09 05:20:38 tb Exp $ */
 
 /*
  * Copyright (c) 2026 Theo Buehler <tb@openbsd.org>
@@ -77,6 +77,23 @@ static const uint8_t secp384r1_hybrid_point[] = {
 };
 static const size_t secp384r1_hybrid_point_len = sizeof(secp384r1_hybrid_point);
 
+static const uint8_t secp384r1_invalid_point[] = {
+	0x04, 0xca, 0x0e, 0xc0, 0x60, 0xce, 0x24, 0x25,
+	0xa7, 0x6e, 0xd1, 0x96, 0x69, 0x33, 0x36, 0x04,
+	0x87, 0x69, 0x36, 0xfd, 0x2a, 0x83, 0x7a, 0x99,
+	0xad, 0xb7, 0x35, 0xe9, 0x4c, 0x2f, 0x56, 0xfc,
+	0xee, 0x7e, 0x68, 0x43, 0x90, 0x41, 0xb7, 0x3c,
+	0x64, 0xd4, 0xec, 0x82, 0xc1, 0xc6, 0xd9, 0x4b,
+	0x7d, 0xfa, 0xaa, 0x43, 0x46, 0x19, 0x94, 0x7f,
+	0xb4, 0xe2, 0xa7, 0xbd, 0x75, 0xaf, 0x4d, 0x8f,
+	0x45, 0xed, 0x3a, 0x8f, 0xef, 0x93, 0x57, 0x50,
+	0x3f, 0x24, 0xf4, 0xa8, 0x68, 0x22, 0xf8, 0xa3,
+	0x8c, 0xa9, 0x8b, 0xe8, 0xb9, 0x28, 0xff, 0x9f,
+	0xcf, 0xcd, 0xac, 0xc1, 0x20, 0x5f, 0x23, 0x07,
+	0x41,
+};
+static const size_t secp384r1_invalid_point_len = sizeof(secp384r1_invalid_point);
+
 static int
 ssl_key_share_ecdhe_test(void)
 {
@@ -161,6 +178,22 @@ ssl_key_share_ecdhe_test(void)
 	EC_KEY_free(ecdh_peer);
 	ecdh_peer = NULL;
 
+	decode_error = 0;
+	CBS_init(&cbs, secp384r1_invalid_point, secp384r1_invalid_point_len);
+	if ((ecdh_peer = EC_KEY_new()) == NULL)
+		err(1, NULL);
+	if (ssl_kex_peer_public_ecdhe_ecp(ecdh_peer, nid, &cbs, &decode_error)) {
+		fprintf(stderr, "FAIL: parsed invalid P-384 point\n");
+		failed |= 1;
+	}
+	if (!decode_error) {
+		fprintf(stderr, "FAIL: no decode_error for invalid P-384 point\n");
+		failed |= 1;
+	}
+
+	EC_KEY_free(ecdh_peer);
+	ecdh_peer = NULL;
+
 	EC_KEY_free(ecdh);
 	freezero(shared_key, shared_key_len);