From f8633c7f01c596199f93cbf1c7e59e276ad8bbed Mon Sep 17 00:00:00 2001
From: Dorian Wouters <elementw@openmailbox.org>
Date: Tue, 16 Aug 2016 15:05:34 +0200
Subject: [PATCH] Init commit

---
 .gitmodules |   3 +
 README.md   | 119 ++++++++++++++++++++
 init.lua    | 309 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 mysql       |   1 +
 4 files changed, 432 insertions(+)
 create mode 100644 .gitmodules
 create mode 100644 README.md
 create mode 100644 init.lua
 create mode 160000 mysql

diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..4377b47
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "mysql"]
+	path = mysql
+	url = https://github.com/luapower/mysql
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..9a57cf7
--- /dev/null
+++ b/README.md
@@ -0,0 +1,119 @@
+# mysql_auth
+
+Plug Minetest's auth mechanism into a MySQL database.
+
+# Configuration
+
+By default `mysql_auth` doesn't run in singleplayer. This can be overriden by setting
+`mysql_auth.enable_singleplayer` to `true`.
+
+Configuration may be done as regular Minetest settings entries, or using a config file, allowing
+for more configuration options; to do so specify the path as `mysql_auth.cfgfile`. This config
+must contain a Lua table that can be read by `minetest.deserialize`, i.e. a regular table
+definition follwing a `return` statement (see the example below).
+
+When using flat Minetest configuation entries, all the following option names must be prefixed
+with `mysql_auth.`. When using a config file, entries are to be hierarchised as per the dot
+separator.
+
+Values written next to option names are default values.
+
+## Database connection
+
+### Flat config file
+
+```lua
+db.host = 'localhost'
+db.user = nil -- MySQL connector defaults to current username
+db.pass = nil -- Using password: NO
+db.port = nil -- MySQL connector defaults to either 3306, or no port if using localhost/unix socket
+db.db = nil -- <== Setting this is required
+```
+
+### Lua table config file
+
+Connection options are passed as a table through the `db.connopts` entry.
+Its format must be the same as [LuaPower's MySQL module `mysql.connect(options_t)` function][mycn],
+that is (all members are optional);
+
+```lua
+connopts = {
+  host = ...,
+  user = ...,
+  pass = ...,
+  db = ...,
+  port = ...,
+  unix_socket = ...,
+  flags = { ... },
+  options = { ... },
+  attrs = { ... },
+  -- Also key, cert, ca, cpath, cipher
+}
+```
+
+## Auth table schema finetuning
+
+```lua
+db.tables.auths.name = 'auths'
+db.tables.auths.schema.userid = 'userid'
+db.tables.auths.schema.userid_type = 'INT'
+db.tables.auths.schema.username = 'username'
+db.tables.auths.schema.username_type = 'VARCHAR(32)'
+db.tables.auths.schema.password = 'password'
+db.tables.auths.schema.password_type = 'VARCHAR(512)'
+db.tables.auths.schema.privs = 'privs'
+db.tables.auths.schema.privs_type = 'VARCHAR(512)'
+db.tables.auths.schema.lastlogin = 'lastlogin'
+db.tables.auths.schema.lastlogin_type = 'BIGINT'
+```
+
+The `_type` config entries are only used when creating an auth table, i.e. when
+`db.tables.auths.name` doesn't exist.
+
+## Examples
+
+### Example 1
+
+#### Using a Lua config file
+
+`minetest.conf`:
+```
+mysql_auth.cfgfile = /srv/minetest/skyblock/mysql_auth_config
+```
+
+`/srv/minetest/skyblock/mysql_auth_config`:
+```lua
+return {
+  db = {
+    connopts = {
+      user = 'minetest',
+      pass = 'BQy77wK$Um6es3Bi($iZ*w3N',
+      db = 'minetest'
+    }
+    tables = {
+      auths = {
+        name = 'skyblock_auths'
+      }
+    }
+  }
+}
+```
+
+#### Using only Minetest config entries
+
+`minetest.conf`:
+```
+mysql_auth.db.user = 'minetest'
+mysql_auth.db.pass = 'BQy77wK$Um6es3Bi($iZ*w3N'
+mysql_auth.db.db = 'minetest'
+mysql_auth.db.tables.auth.name = 'skyblock_auths'
+```
+
+# License
+
+`mysql_auth` is licensed under [LGPLv3](https://www.gnu.org/licenses/lgpl.html).
+
+Using the Public Domain-licensed LuaPower `mysql` module.
+
+
+[mycn]: https://luapower.com/mysql#mysql.connectoptions_t---conn
diff --git a/init.lua b/init.lua
new file mode 100644
index 0000000..a83958b
--- /dev/null
+++ b/init.lua
@@ -0,0 +1,309 @@
+local modname = minetest.get_current_modname()
+local modpath = minetest.get_modpath(modname) 
+
+local thismod = {}
+_G[modname] = thismod
+
+if not minetest.setting_get(modname .. '.enable_singleplayer') and minetest.is_singleplayer() then
+  core.log('action', modname .. ": Not adding auth handler because of singleplayer game")
+  return
+end
+
+local function setoverlay(tab, orig)
+  local mt = getmetatable(tab) or {}
+  mt.__index = function (tab, key)
+    if rawget(tab, key) ~= nil then
+      return rawget(tab, key)
+    else
+      return orig[key]
+    end
+  end
+  setmetatable(tab, mt)
+end
+
+local function string_splitdots(s)
+  local temp = {}
+  local index = 0
+  local last_index = string.len(s)
+  while true do
+    local i, e = string.find(s, '%.', index)
+    if i and e then
+      local next_index = e + 1
+      local word_bound = i - 1
+      table.insert(temp, string.sub(s, index, word_bound))
+      index = next_index
+    else            
+      if index > 0 and index <= last_index then
+        table.insert(temp, string.sub(s, index, last_index))
+      elseif index == 0 then
+        temp = nil
+      end
+      break
+    end
+  end
+  return temp
+end
+
+local mysql
+do -- MySQL module loading
+  local env = {
+    require = function (module)
+      if module == 'mysql_h' then
+        return dofile(modpath .. '/mysql/mysql_h.lua')
+      else
+        return require(module)
+      end
+    end
+  }
+  setoverlay(env, _G)
+  local fn, msg = loadfile(modpath .. '/mysql/mysql.lua')
+  if not fn then error(msg) end
+  setfenv(fn, env)
+  local status
+  status, mysql = pcall(fn, {})
+  if not status then
+    error(modname .. ' failed to load MySQL FFI interface: ' .. mysql)
+  end
+end
+
+do
+  local get
+  do
+    get = function (name) return minetest.setting_get(modname .. '.' .. name) end
+    local cfgfile = get('cfgfile')
+    if type(cfgfile) == 'string' and cfgfile ~= '' then
+      local file = io.open(cfgfile, 'rb')
+      if not file then
+        error(modname .. ' failed to load specified config file at ' .. cfgfile)
+      end
+      local cfg = minetest.deserialize(file:read('*a'))
+      file:close()
+      get = function (name)
+        if type(name) ~= 'string' or name == '' then
+          return nil
+        end
+        local parts = string_splitdots(name)
+        local tbl = cfg[parts[1]]
+        for n = 2, #parts do
+          if tbl == nil then
+            return nil
+          end
+          tbl = tbl[parts[n]]
+        end
+        return tbl
+      end
+    end
+  end
+
+  local conn, db
+  do
+    -- MySQL API backend
+    mysql.config(get('db.api'))
+
+    local connopts = get('db.connopts')
+    if type(connopts) == 'table' then
+      -- User-specified connection parameter table
+      -- Only when using a config file
+      db = connopts.db
+      connopts.charset = 'utf8'
+      conn = mysql.connect(connopts)
+    elseif get('db.db') ~= nil then
+      -- Traditional connection parameters
+      local host, user, port = get('db.host') or 'localhost', get('db.user'), get('db.port')
+      local pass = get('db.pass')
+      db = get('db.db')
+      conn = mysql.connect(host, user, pass, db, 'utf8', port)
+    else
+      error(modname .. ": missing db.db parameter")
+    end
+    thismod.conn = conn
+
+    -- LuaPower's MySQL interface throws an error when the connection fails, no need to check if
+    -- it succeeded.
+
+    -- Ensure UTF-8 is in use.
+    -- If you use another encoding, kill yourself (unless it's UTF-32).
+    conn:query("SET NAMES 'utf8'")
+    conn:query("SET CHARACTER SET utf8")
+    conn:query("SET character_set_results = 'utf8', character_set_client = 'utf8'," ..
+                   "character_set_connection = 'utf8', character_set_database = 'utf8'," ..
+                   "character_set_server = 'utf8'")
+  end
+
+  local tables = {}
+  do -- Tables and schema settings
+    local t_auths = get('db.tables.auths')
+    if type(t_auths) == 'table' then
+      tables.auths = t_auths
+    else
+      tables.auths = {}
+      tables.auths.name = get('db.tables.auths.name')
+      tables.auths.schema = {}
+      local S = tables.auths.schema
+      S.userid = get('db.tables.auths.schema.userid')
+      S.username = get('db.tables.auths.schema.username')
+      S.password = get('db.tables.auths.schema.password')
+      S.privs = get('db.tables.auths.schema.privs')
+      S.lastlogin = get('db.tables.auths.schema.lastlogin')
+      S.userid_type = get('db.tables.auths.schema.userid_type')
+      S.username_type = get('db.tables.auths.schema.username_type')
+      S.password_type = get('db.tables.auths.schema.password_type')
+      S.privs_type = get('db.tables.auths.schema.privs_type')
+      S.lastlogin_type = get('db.tables.auths.schema.lastlogin_type')
+    end
+
+    do -- Default values
+      tables.auths.name = tables.auths.name or 'auths'
+      tables.auths.schema = tables.auths.schema or {}
+      local S = tables.auths.schema
+      S.userid = S.userid or 'userid'
+      S.username = S.username or 'username'
+      S.password = S.password or 'password'
+      S.privs = S.privs or 'privs'
+      S.lastlogin = S.lastlogin or 'lastlogin'
+
+      S.userid_type = S.userid_type or 'INT'
+      S.username_type = S.username_type or 'VARCHAR(32)'
+      S.password_type = S.password_type or 'VARCHAR(512)'
+      S.privs_type = S.privs_type or 'VARCHAR(512)'
+      S.lastlogin_type = S.lastlogin_type or 'BIGINT'
+      -- Note lastlogin doesn't use the TIMESTAMP type, which is 32-bit and therefore
+      -- subject to the year 2038 problem.
+    end
+  end
+
+  do -- Auth table existence check and setup
+    conn:query("SHOW TABLES LIKE '" .. tables.auths.name .. "'")
+    local res = conn:store_result()
+    local exists = (res:row_count() ~= 0)
+    res:free()
+    if not exists then
+      -- Auth table doesn't exist, create it
+      local S = tables.auths.schema
+      conn:query('CREATE TABLE ' .. tables.auths.name .. ' (' ..
+        S.userid  .. ' ' .. S.userid_type .. ' NOT NULL AUTO_INCREMENT,' ..
+        S.username .. ' ' .. S.username_type .. ' NOT NULL,' ..
+        S.password .. ' ' .. S.password_type .. ' NOT NULL,' ..
+        S.privs .. ' ' .. S.privs_type .. ' NOT NULL,' ..
+        S.lastlogin .. ' ' .. S.lastlogin_type .. ',' ..
+        'PRIMARY KEY (' .. S.userid .. '),' ..
+        'UNIQUE (' .. S.username .. ')' ..
+      ')')
+    end
+  end
+
+  local S = tables.auths.schema
+  local get_auth_stmt = conn:prepare('SELECT ' .. S.password .. ',' .. S.privs .. ',' ..
+    S.lastlogin .. ' FROM ' .. tables.auths.name .. ' WHERE ' .. S.username .. '=?')
+  local get_auth_params = get_auth_stmt:bind_params({S.username_type})
+  local get_auth_results = get_auth_stmt:bind_result({S.password_type, S.privs_type,
+    S.lastlogin_type})
+
+  local create_auth_stmt = conn:prepare('INSERT INTO ' .. tables.auths.name .. '(' .. S.username ..
+    ',' .. S.password .. ',' .. S.privs .. ') VALUES (?,?,?)')
+  local create_auth_params = create_auth_stmt:bind_params({S.username_type, S.password_type,
+    S.privs_type})
+
+  local set_password_stmt = conn:prepare('UPDATE ' .. tables.auths.name .. ' SET ' .. S.password ..
+    '=? WHERE ' .. S.username .. '=?')
+  local set_password_params = set_password_stmt:bind_params({S.password_type, S.username_type})
+
+  local set_privileges_stmt = conn:prepare('UPDATE ' .. tables.auths.name .. ' SET ' .. S.privs ..
+      '=? WHERE ' .. S.username .. '=?')
+  local set_privileges_params = set_privileges_stmt:bind_params({S.privs_type, S.username_type})
+
+  local record_login_stmt = conn:prepare('UPDATE ' .. tables.auths.name .. ' SET ' ..
+    S.lastlogin .. '=? WHERE ' .. S.username .. '=?')
+  local record_login_params = record_login_stmt:bind_params({S.lastlogin_type, S.username_type})
+
+  thismod.auth_handler = {
+    get_auth = function(name)
+      assert(type(name) == 'string')
+      get_auth_params:set(1, name)
+      local success, msg = pcall(function () get_auth_stmt:exec() end)
+      if not success then
+        minetest.log('error', modname .. ': get_auth failed: ' .. msg)
+        return nil
+      end
+      if not get_auth_stmt:fetch() then
+        minetest.log('error', modname .. ': get_auth failed: get_auth_stmt:fetch() returned false')
+        return nil
+      end
+      local password, privs_str, lastlogin = get_auth_results:get(1), get_auth_results:get(2),
+        get_auth_results:get(3)
+      get_auth_stmt:free_result()
+      return {
+        password = password,
+        privileges = minetest.string_to_privs(privs_str),
+        last_login = lastlogin
+      }
+    end,
+    create_auth = function(name, password, reason)
+      assert(type(name) == 'string')
+      assert(type(password) == 'string')
+      minetest.log('info', modname .. " creating player '"..name.."'" .. (reason or ""))
+      create_auth_params:set(1, name)
+      create_auth_params:set(2, password)
+      create_auth_params:set(3, minetest.setting_get("default_privs"))
+      local success, msg = pcall(function () create_auth_stmt:exec() end)
+      if not success then
+        minetest.log('error', modname .. ': create_auth failed: ' .. msg)
+        return false
+      end
+      return true
+    end,
+    set_password = function(name, password)
+      assert(type(name) == 'string')
+      assert(type(password) == 'string')
+      if not thismod.auth_handler.get_auth(name) then
+        thismod.auth_handler.create_auth(name, password, ' because set_password was requested')
+      else
+        minetest.log('info', modname .. " setting password of player '"..name.."'")
+        set_password_params:set(1, password)
+        set_password_params:set(2, name)
+        local success, msg = pcall(function () set_password_stmt:exec() end)
+        if not success then
+          minetest.log('error', modname .. ': set_password failed: ' .. msg)
+          return false
+        end
+      end
+      return true
+    end,
+    set_privileges = function(name, privileges)
+      assert(type(name) == 'string')
+      assert(type(privileges) == 'table')
+      set_privileges_params:set(1, minetest.privs_to_string(privileges))
+      set_privileges_params:set(2, name)
+      local success, msg = pcall(function () set_privileges_stmt:exec() end)
+      if not success then
+        minetest.log('error', modname .. ': set_privileges failed: ' .. msg)
+        return false
+      end
+      minetest.notify_authentication_modified(name)
+      return true
+    end,
+    reload = function()
+      return true
+    end,
+    record_login = function(name)
+      assert(type(name) == 'string')
+      record_login_params:set(1, math.floor(os.time()))
+      record_login_params:set(2, name)
+      local success, msg = pcall(function () record_login_stmt:exec() end)
+      if not success then
+        minetest.log('error', modname .. ': record_login failed: ' .. msg)
+        return false
+      end
+      return true
+    end
+  }
+end
+
+minetest.register_authentication_handler(thismod.auth_handler)
+minetest.log('action', modname .. ": Registered auth handler")
+
+minetest.register_on_shutdown(function()
+  if thismod.conn then
+    thismod.conn:close()
+  end
+end)
diff --git a/mysql b/mysql
new file mode 160000
index 0000000..4bc8277
--- /dev/null
+++ b/mysql
@@ -0,0 +1 @@
+Subproject commit 4bc82774707695bf934682eb401ed44ab06d63d5