diff --git a/authfs/testdata/README.md b/authfs/testdata/README.md
new file mode 100644
index 0000000..113fe62
--- /dev/null
+++ b/authfs/testdata/README.md
@@ -0,0 +1,9 @@
+fs-verity signing
+=================
+With a key pair, fs-verity signature can be generated by simply running
+`fsverity` command line tool from
+[fsverity-util](https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/fsverity-utils.git).
+
+```
+fsverity sign test.data test.data.fsv_sig --key=key.pem --cert=cert.pem
+```
diff --git a/authfs/testdata/cert.der b/authfs/testdata/cert.der
new file mode 100644
index 0000000..e7e2273
--- /dev/null
+++ b/authfs/testdata/cert.der
Binary files differ
diff --git a/authfs/testdata/cert.pem b/authfs/testdata/cert.pem
new file mode 100644
index 0000000..0a380f3
--- /dev/null
+++ b/authfs/testdata/cert.pem
@@ -0,0 +1,32 @@
+-----BEGIN CERTIFICATE-----
+MIIFmzCCA4OgAwIBAgIUbgQdchyPL/bN/LLgs8CPJU+fO10wDQYJKoZIhvcNAQEL
+BQAwXTELMAkGA1UEBhMCVVMxEzARBgNVBAgMCkNhbGlmb3JuaWExFjAUBgNVBAcM
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+gqHoGWlxMlRl5Qd5LdmZ1L1ASyjH5Yk8QhLCFoNjLYkEfAbDyc4hi5y5sccMDrA=
+-----END CERTIFICATE-----
diff --git a/authfs/testdata/input.4k.fsv_sig b/authfs/testdata/input.4k.fsv_sig
new file mode 100644
index 0000000..247a297
--- /dev/null
+++ b/authfs/testdata/input.4k.fsv_sig
Binary files differ
diff --git a/authfs/testdata/input.4k1.fsv_sig b/authfs/testdata/input.4k1.fsv_sig
new file mode 100644
index 0000000..02f0056
--- /dev/null
+++ b/authfs/testdata/input.4k1.fsv_sig
Binary files differ
diff --git a/authfs/testdata/input.4m.fsv_sig b/authfs/testdata/input.4m.fsv_sig
new file mode 100644
index 0000000..12adca3
--- /dev/null
+++ b/authfs/testdata/input.4m.fsv_sig
Binary files differ
diff --git a/authfs/testdata/key.pem b/authfs/testdata/key.pem
new file mode 100644
index 0000000..c8520f8
--- /dev/null
+++ b/authfs/testdata/key.pem
@@ -0,0 +1,52 @@
+-----BEGIN PRIVATE KEY-----
+MIIJQwIBADANBgkqhkiG9w0BAQEFAASCCS0wggkpAgEAAoICAQDAHeyQArSPm8IE
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+-----END PRIVATE KEY-----