From b12ad292d4dfef1c00567fe3def7e73461d3c217 Mon Sep 17 00:00:00 2001
From: Jakob Unterwurzacher <jakobunt@gmail.com>
Date: Mon, 23 Aug 2021 16:17:04 +0200
Subject: [PATCH] tests/cli: add -xchacha tests

---
 tests/cli/cli_test.go     |  3 +-
 tests/cli/xchacha_test.go | 66 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+), 2 deletions(-)
 create mode 100644 tests/cli/xchacha_test.go

diff --git a/tests/cli/cli_test.go b/tests/cli/cli_test.go
index 4055c97..96a5b72 100644
--- a/tests/cli/cli_test.go
+++ b/tests/cli/cli_test.go
@@ -1,7 +1,6 @@
+// package cli tests CLI operations like "-init", "-password" etc
 package cli
 
-// Test CLI operations like "-init", "-password" etc
-
 import (
 	"fmt"
 	"io/ioutil"
diff --git a/tests/cli/xchacha_test.go b/tests/cli/xchacha_test.go
new file mode 100644
index 0000000..7f24c8b
--- /dev/null
+++ b/tests/cli/xchacha_test.go
@@ -0,0 +1,66 @@
+package cli
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"syscall"
+	"testing"
+
+	"github.com/rfjakob/gocryptfs/v2/internal/configfile"
+
+	"github.com/rfjakob/gocryptfs/v2/tests/test_helpers"
+)
+
+// Create "-xchacha" fs
+func TestInitXchacha(t *testing.T) {
+	cDir := test_helpers.InitFS(nil, "-xchacha")
+	// Check config file sanity
+	_, c, err := configfile.LoadAndDecrypt(cDir+"/"+configfile.ConfDefaultName, testPw)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	if c.IsFeatureFlagSet(configfile.FlagGCMIV128) {
+		t.Error("GCMIV128 flag should be off")
+	}
+	if !c.IsFeatureFlagSet(configfile.FlagXChaCha20Poly1305) {
+		t.Error("XChaCha20Poly1305 flag should be on")
+	}
+	if !c.IsFeatureFlagSet(configfile.FlagHKDF) {
+		t.Error("HKDF flag should be on")
+	}
+}
+
+// Create and mount "-xchacha" fs, and see if we get the expected file sizes
+// (xchacha has longer IVs).
+func TestXchacha(t *testing.T) {
+	cDir := test_helpers.InitFS(nil, "-xchacha", "-plaintextnames")
+	pDir := cDir + ".mnt"
+	test_helpers.MountOrExit(cDir, pDir, "-extpass", "echo test")
+	defer test_helpers.UnmountPanic(pDir)
+
+	if err := ioutil.WriteFile(pDir+"/1byte", []byte("x"), 0700); err != nil {
+		t.Fatal(err)
+	}
+	var st syscall.Stat_t
+	if err := syscall.Stat(cDir+"/1byte", &st); err != nil {
+		t.Fatal(err)
+	}
+	// 2 byte version header + 16 byte file id + 192 bit xchacha iv + 1 byte payload + 16 byte mac
+	if st.Size != 2+16+24+1+16 {
+		t.Errorf("wrong size %d", st.Size)
+	}
+
+	// 1 MiB = 256 4kiB blocks
+	if err := ioutil.WriteFile(pDir+"/1MiB", make([]byte, 1024*1024), 0700); err != nil {
+		t.Fatal(err)
+	}
+	if err := syscall.Stat(cDir+"/1MiB", &st); err != nil {
+		t.Fatal(err)
+	}
+	// 2 byte version header + (16 byte file id + 192 bit xchacha iv + 4096 byte payload + 16 byte mac)*256
+	if st.Size != 2+16+(24+4096+16)*256 {
+		t.Errorf("wrong size %d", st.Size)
+	}
+}