From fe2f27c131a3b0298eda8aa58cf9524705e1d19a Mon Sep 17 00:00:00 2001
From: djm <djm@openbsd.org>
Date: Thu, 2 Feb 2023 12:12:52 +0000
Subject: [PATCH] test compat_kex_proposal(); by dtucker@

---
 regress/usr.bin/ssh/unittests/kex/Makefile    |  4 +-
 .../usr.bin/ssh/unittests/kex/test_proposal.c | 79 +++++++++++++++++++
 regress/usr.bin/ssh/unittests/kex/tests.c     |  4 +-
 3 files changed, 84 insertions(+), 3 deletions(-)
 create mode 100644 regress/usr.bin/ssh/unittests/kex/test_proposal.c

diff --git a/regress/usr.bin/ssh/unittests/kex/Makefile b/regress/usr.bin/ssh/unittests/kex/Makefile
index 4e6548115aa..981affe3cbe 100644
--- a/regress/usr.bin/ssh/unittests/kex/Makefile
+++ b/regress/usr.bin/ssh/unittests/kex/Makefile
@@ -1,7 +1,7 @@
-#	$OpenBSD: Makefile,v 1.13 2023/01/15 23:35:10 djm Exp $
+#	$OpenBSD: Makefile,v 1.14 2023/02/02 12:12:52 djm Exp $
 
 PROG=test_kex
-SRCS=tests.c test_kex.c
+SRCS=tests.c test_kex.c test_proposal.c
 
 # From usr.bin/ssh
 SRCS+=sshbuf-getput-basic.c sshbuf-getput-crypto.c sshbuf-misc.c sshbuf.c
diff --git a/regress/usr.bin/ssh/unittests/kex/test_proposal.c b/regress/usr.bin/ssh/unittests/kex/test_proposal.c
new file mode 100644
index 00000000000..b89ff59b6d8
--- /dev/null
+++ b/regress/usr.bin/ssh/unittests/kex/test_proposal.c
@@ -0,0 +1,79 @@
+/* 	$OpenBSD: test_proposal.c,v 1.1 2023/02/02 12:12:52 djm Exp $ */
+/*
+ * Regress test KEX
+ *
+ * Placed in the public domain
+ */
+
+#include <sys/types.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "test_helper.h"
+
+#include "compat.h"
+#include "ssherr.h"
+#include "sshbuf.h"
+#include "kex.h"
+#include "packet.h"
+#include "xmalloc.h"
+
+void kex_proposal(void);
+
+#define CURVE25519 "curve25519-sha256@libssh.org"
+#define DHGEX1 "diffie-hellman-group-exchange-sha1"
+#define DHGEX256 "diffie-hellman-group-exchange-sha256"
+#define KEXALGOS CURVE25519","DHGEX256","DHGEX1
+void
+kex_proposal(void)
+{
+	size_t i;
+	struct ssh ssh;
+	char *result, *out, *in;
+	struct {
+		char *in;	/* TODO: make this const */
+		char *out;
+		int compat;
+	} tests[] = {
+		{ KEXALGOS, KEXALGOS, 0},
+		{ KEXALGOS, DHGEX256","DHGEX1, SSH_BUG_CURVE25519PAD },
+		{ KEXALGOS, CURVE25519, SSH_OLD_DHGEX },
+		{ "a,"KEXALGOS, "a", SSH_BUG_CURVE25519PAD|SSH_OLD_DHGEX },
+		/* TODO: enable once compat_kex_proposal doesn't fatal() */
+		/* { KEXALGOS, "", SSH_BUG_CURVE25519PAD|SSH_OLD_DHGEX }, */
+	};
+
+	TEST_START("compat_kex_proposal");
+	for (i = 0; i < sizeof(tests) / sizeof(*tests); i++) {
+		ssh.compat = tests[i].compat;
+		/* match entire string */
+		result = compat_kex_proposal(&ssh, tests[i].in);
+		ASSERT_STRING_EQ(result, tests[i].out);
+		free(result);
+		/* match at end */
+		in = kex_names_cat("a", tests[i].in);
+		out = kex_names_cat("a", tests[i].out);
+		result = compat_kex_proposal(&ssh, in);
+		ASSERT_STRING_EQ(result, out);
+		free(result); free(in); free(out);
+		/* match at start */
+		in = kex_names_cat(tests[i].in, "a");
+		out = kex_names_cat(tests[i].out, "a");
+		result = compat_kex_proposal(&ssh, in);
+		ASSERT_STRING_EQ(result, out);
+		free(result); free(in); free(out);
+		/* match in middle */
+		xasprintf(&in, "a,%s,b", tests[i].in);
+		if (*(tests[i].out) == '\0')
+			out = xstrdup("a,b");
+		else
+			xasprintf(&out, "a,%s,b", tests[i].out);
+		result = compat_kex_proposal(&ssh, in);
+		ASSERT_STRING_EQ(result, out);
+		free(result); free(in); free(out);
+	}
+	TEST_DONE();
+}
diff --git a/regress/usr.bin/ssh/unittests/kex/tests.c b/regress/usr.bin/ssh/unittests/kex/tests.c
index 1e519fe4b1e..26592d54505 100644
--- a/regress/usr.bin/ssh/unittests/kex/tests.c
+++ b/regress/usr.bin/ssh/unittests/kex/tests.c
@@ -1,4 +1,4 @@
-/* 	$OpenBSD: tests.c,v 1.1 2015/01/15 23:41:29 markus Exp $ */
+/* 	$OpenBSD: tests.c,v 1.2 2023/02/02 12:12:52 djm Exp $ */
 /*
  * Placed in the public domain
  */
@@ -6,9 +6,11 @@
 #include "test_helper.h"
 
 void kex_tests(void);
+void kex_proposal(void);
 
 void
 tests(void)
 {
 	kex_tests();
+	kex_proposal();
 }
-- 
2.20.1