diff --git a/src/main/resources/assets/opencomputers/lua/component/data/bin/gpg.lua b/src/main/resources/assets/opencomputers/lua/component/data/bin/gpg.lua
index d7c92f972..0d156d959 100644
--- a/src/main/resources/assets/opencomputers/lua/component/data/bin/gpg.lua
+++ b/src/main/resources/assets/opencomputers/lua/component/data/bin/gpg.lua
@@ -12,222 +12,225 @@ local serialization = require("serialization")
 local args, options = shell.parse(...)
 
 local function writeFile(path, data)
-    if filesystem.exists(path) then
-        print("gpg: failed to write file: " .. path)
-        print("gpg: error was: file already exists")
-        return false
-    end
+  if filesystem.exists(path) then
+    io.stderr:write("gpg: failed to write file: " .. path .. "\n")
+    io.stderr:write("gpg: error was: file already exists\n")
+    return false
+  end
 
-    if type(data) == "table" then
-        data = serialization.serialize(data)
-    end
+  if type(data) == "table" then
+    data = serialization.serialize(data)
+  end
 
-    local h, err = io.open(path, "wb")
+  local h, err = io.open(path, "wb")
 
-    if not h then
-        print("gpg: failed to write file: " .. path)
-        print("gpg: error was: " .. err)
-        return false
-    end
+  if not h then
+    io.stderr:write("gpg: failed to write file: " .. path .. "\n")
+    io.stderr:write("gpg: error was: " .. err .. "\n")
+    return false
+  end
 
-    h:write(data)
-    h:close()
-    return true
+  h:write(data)
+  h:close()
+  return true
 end
 
 local function readFile(path, deserialize)
-    local h = io.open(path, "rb")
-    local r = h:read("*a")
-    h:close()
+  local h = io.open(path, "rb")
+  local r = h:read("*a")
+  h:close()
 
-    if deserialize then
-        r = serialization.unserialize(r)
-    end
+  if deserialize then
+    r = serialization.unserialize(r)
+  end
 
-    return r
+  return r
 end
 
 local function parseKey(path, isPublic)
-    local d = readFile(path, true)
-    local k, err = data.deserializeKey(d.d, d.t)
+  local d = readFile(path, true)
+  local k, err = data.deserializeKey(d.d, d.t)
 
-    if not k then
-        print("gpg: failed to parse key: " .. err)
-        return nil
-    end
+  if not k then
+    io.stderr:write("gpg: failed to parse key: " .. err .. "\n")
+    return nil
+  end
 
-    if k.isPublic() ~= isPublic then
-        print("gpg: wrong key type")
-        return nil
-    end
+  if k.isPublic() ~= isPublic then
+    io.stderr:write("gpg: wrong key type\n")
+    return nil
+  end
 
-    return k
+  return k
 end
 
 local function deriveName(base, encrypt)
-    if encrypt then
-        return base .. ".gpg"
-    else
-        local d = base:gsub(".gpg", "")
-        if d == base then
-            d = d .. ".dec"
-            print("gpg: decrypting to " .. d)
-        end
-        return d
+  if encrypt then
+    return base .. ".gpg"
+  else
+    local d = base:gsub(".gpg", "")
+    if d == base then
+      d = d .. ".dec"
+      io.write("gpg: decrypting to " .. d .. "\n")
     end
+    return d
+  end
 end
 
-local function ensureTier(tier)
-    if not require("component").isAvailable("data") then
-        print("gpg: you must have data card in order to run this program")
-        error("data card is absent")
-    end
+local function ensureMethods(...)
+  if not require("component").isAvailable("data") then
+    io.stderr:write("gpg: you must have data card in order to run this program\n")
+    error("data card is absent")
+  end
 
-    if data.tier() < tier then
-        print("gpg: you must have tier " .. tier .. " data card in order to run this program")
-        error("data card is too simple")
+  local names = table.pack(...)
+  for i = 1, names.n do
+    if names[i] and not data[names[i]] then
+      io.stderr:write("gpg: method " .. names[i] .. " required on data card to run this program\n")
+      error("data card tier insufficient")
     end
+  end
 end
 
 if options['g'] and (#args == 2) then
-    ensureTier(3)
-    local pub, priv = data.generateKeyPair(384)
+  ensureMethods("generateKeyPair")
+  local pub, priv = data.generateKeyPair(384)
 
-    priv = { t = priv.keyType(), d = priv.serialize() }
-    pub = { t = pub.keyType(), d = pub.serialize() }
+  priv = { t = priv.keyType(), d = priv.serialize() }
+  pub = { t = pub.keyType(), d = pub.serialize() }
 
-    if not writeFile(args[1], priv) then
-        print("gpg: failed to write private key, aborting")
-        return false
-    end
+  if not writeFile(args[1], priv) then
+    io.stderr:write("gpg: failed to write private key, aborting\n")
+    return false
+  end
 
-    if not writeFile(args[2], pub) then
-        print("gpg: failed to write public key, aborting")
-        return false
-    end
+  if not writeFile(args[2], pub) then
+    io.stderr:write("gpg: failed to write public key, aborting\n")
+    return false
+  end
 
-    return true
+  return true
 end
 
 if options['c'] and (options['e'] or options['d']) and (#args == 1) then
-    ensureTier(2)
-    if options['d'] and options['e'] then
-        print("gpg: please specify either -d or -e")
-        return false
+  ensureMethods("md5", "sha256", "encrypt", "decrypt", "random")
+  if options['d'] and options['e'] then
+    io.stderr:write("gpg: please specify either -d or -e\n")
+    return false
+  end
+
+  io.write("gpg: enter password: ")
+  local aesKey = data.md5(term.read(nil, nil, nil, "*"))
+  local checkValue = data.sha256(aesKey)
+
+  if options['e'] then
+    local iv = data.random(16)
+    local d = data.encrypt(readFile(args[1]), aesKey, iv)
+
+    return writeFile(deriveName(args[1], true), {
+      t = "pwd",
+      kdf = "md5",
+      iv = iv,
+      cv = checkValue,
+      d = d
+    })
+  else
+    local d = readFile(args[1], true)
+
+    if d.t ~= "pwd" then
+      io.stderr:write("gpg: file is not encrypted with a password\n")
+      return false
     end
 
-    io.write("gpg: enter password: ")
-    local aesKey = data.md5(term.read(nil, nil, nil, "*"))
-    local checkValue = data.sha256(aesKey)
-
-    if options['e'] then
-        local iv = data.random(16)
-        local d = data.encrypt(readFile(args[1]), aesKey, iv)
-
-        return writeFile(deriveName(args[1], true), {
-            t = "pwd",
-            kdf = "md5",
-            iv = iv,
-            cv = checkValue,
-            d = d
-        })
-    else
-        local d = readFile(args[1], true)
-
-        if d.t ~= "pwd" then
-            print("gpg: file is not encrypted with a password")
-            return false
-        end
-
-        if checkValue ~= d.cv then
-            print("gpg: password incorrect")
-            return false
-        end
-
-        return writeFile(deriveName(args[1], false), data.decrypt(d.d, aesKey, d.iv))
+    if checkValue ~= d.cv then
+      io.stderr:write("gpg: password incorrect\n")
+      return false
     end
+
+    return writeFile(deriveName(args[1], false), data.decrypt(d.d, aesKey, d.iv))
+  end
 end
 
 if (options['d'] or options['e']) and (#args == 2) then
-    ensureTier(3)
-    if options['d'] and options['e'] then
-        print("gpg: please specify either -d or -e")
-        return false
+  ensureMethods("md5", "sha256", "encrypt", "decrypt", "random", "generateKeyPair", "deserializeKey", "ecdh")
+  if options['d'] and options['e'] then
+    io.stderr:write("gpg: please specify either -d or -e\n")
+    return false
+  end
+
+  if options['e'] then
+    local userPub = parseKey(args[1], true)
+    local tmpPub, tmpPriv = data.generateKeyPair(384)
+    local aesKey = data.md5(data.ecdh(tmpPriv, userPub))
+    local checkValue = data.sha256(aesKey)
+    local iv = data.random(16)
+
+    local d = data.encrypt(readFile(args[2]), aesKey, iv)
+    return writeFile(deriveName(args[2], true), {
+      t = "ecdh",
+      kdf = "md5",
+      iv = iv,
+      cv = checkValue,
+      k = {
+        t = tmpPub.keyType(),
+        d = tmpPub.serialize()
+      },
+      d = d
+    })
+  else
+    local userPriv = parseKey(args[1], false)
+    local d = readFile(args[2], true)
+
+    if d.t ~= "ecdh" then
+      io.stderr:write("gpg: file is not encrypted with a key\n")
+      return false
     end
 
-    if options['e'] then
-        local userPub = parseKey(args[1], true)
-        local tmpPub, tmpPriv = data.generateKeyPair(384)
-        local aesKey = data.md5(data.ecdh(tmpPriv, userPub))
-        local checkValue = data.sha256(aesKey)
-        local iv = data.random(16)
+    local tmpPub = data.deserializeKey(d.k.d, d.k.t)
+    local aesKey = data.md5(data.ecdh(userPriv, tmpPub))
 
-        local d = data.encrypt(readFile(args[2]), aesKey, iv)
-        return writeFile(deriveName(args[2], true), {
-            t = "ecdh",
-            kdf = "md5",
-            iv = iv,
-            cv = checkValue,
-            k = {
-                t = tmpPub.keyType(),
-                d = tmpPub.serialize()
-            },
-            d = d
-        })
-    else
-        local userPriv = parseKey(args[1], false)
-        local d = readFile(args[2], true)
-
-        if d.t ~= "ecdh" then
-            print("gpg: file is not encrypted with a key")
-            return false
-        end
-
-        local tmpPub = data.deserializeKey(d.k.d, d.k.t)
-        local aesKey = data.md5(data.ecdh(userPriv, tmpPub))
-
-        if d.cv ~= data.sha256(aesKey) then
-            print("gpg: invalid key")
-            return false
-        end
-
-        return writeFile(deriveName(args[2], false), data.decrypt(d.d, aesKey, d.iv))
+    if d.cv ~= data.sha256(aesKey) then
+      io.stderr:write("gpg: invalid key\n")
+      return false
     end
+
+    return writeFile(deriveName(args[2], false), data.decrypt(d.d, aesKey, d.iv))
+  end
 end
 
 if (options['s'] or options['v']) and (#args == 2) then
-    ensureTier(2)
-    if options['s'] and options['v'] then
-        print("gpg: please specify either -s or -v")
-        return false
+  ensureMethods("deserializeKey", "ecdsa")
+  if options['s'] and options['v'] then
+    io.stderr:write("gpg: please specify either -s or -v\n")
+    return false
+  end
+
+  if options['s'] then
+    local userPriv = parseKey(args[1], false)
+    local sign = data.ecdsa(readFile(args[2]), userPriv)
+
+    return writeFile(args[2] .. ".sig", {
+      t = "ecdsa",
+      s = sign
+    })
+  else
+    local userPub = parseKey(args[1], true)
+    local sign = readFile(args[2] .. ".sig", true)
+
+    if sign.t ~= "ecdsa" then
+      io.stderr:write("gpg: unsupported signature type\n")
+      return false
     end
 
-    if options['s'] then
-        local userPriv = parseKey(args[1], false)
-        local sign = data.ecdsa(readFile(args[2]), userPriv)
-
-        return writeFile(args[2] .. ".sig", {
-            t = "ecdsa",
-            s = sign
-        })
-    else
-        local userPub = parseKey(args[1], true)
-        local sign = readFile(args[2] .. ".sig", true)
-
-        if sign.t ~= "ecdsa" then
-            print("gpg: unsupported signature type")
-            return false
-        end
-
-        if not data.ecdsa(readFile(args[2]), userPub, sign.s) then
-            print("gpg: signature verification failed")
-            return false
-        end
-
-        print("gpg: signature is valid")
-
-        return true
+    if not data.ecdsa(readFile(args[2]), userPub, sign.s) then
+      io.stderr:write("gpg: signature verification failed\n")
+      return false
     end
+
+    io.write("gpg: signature is valid\n")
+
+    return true
+  end
 end
 
 io.write("Usages:\n")
diff --git a/src/main/resources/assets/opencomputers/lua/component/data/lib/data.lua b/src/main/resources/assets/opencomputers/lua/component/data/lib/data.lua
index 62d11cef5..cf5fec5ee 100644
--- a/src/main/resources/assets/opencomputers/lua/component/data/lib/data.lua
+++ b/src/main/resources/assets/opencomputers/lua/component/data/lib/data.lua
@@ -18,21 +18,21 @@ function data.fromHex(hex)
 end
 
 if component.isAvailable("data") then
-    local wrappedFunctions = { 'encode64', 'decode64', 'sha256', 'md5', 'crc32', 'deflate', 'inflate',
-                               'getLimit', 'tier', 'encrypt', 'decrypt', 'random', 'generateKeyPair',
-                               'deserializeKey', 'ecdh', 'ecdsa' }
+  local wrappedFunctions = { 'encode64', 'decode64', 'sha256', 'md5', 'crc32', 'deflate', 'inflate',
+                             'getLimit', 'tier', 'encrypt', 'decrypt', 'random', 'generateKeyPair',
+                             'deserializeKey', 'ecdh', 'ecdsa' }
 
-    function data.present()
-        return true
-    end
+  function data.present()
+    return true
+  end
 
-    for i, v in ipairs(wrappedFunctions) do
-      data[v] = component.data[v]
-    end
+  for _, v in ipairs(wrappedFunctions) do
+    data[v] = component.data[v]
+  end
 else
-    function data.present()
-        return false
-    end
+  function data.present()
+    return false
+  end
 end
 
 return data