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-rw-r--r--daemon/lua/sandbox.lua458
1 files changed, 458 insertions, 0 deletions
diff --git a/daemon/lua/sandbox.lua b/daemon/lua/sandbox.lua
new file mode 100644
index 0000000..017e3a3
--- /dev/null
+++ b/daemon/lua/sandbox.lua
@@ -0,0 +1,458 @@
+local ffi = require('ffi')
+
+-- Units
+kB = 1024
+MB = 1024*kB
+GB = 1024*MB
+-- Time
+sec = 1000
+second = sec
+minute = 60 * sec
+min = minute
+hour = 60 * minute
+day = 24 * hour
+
+-- Logging
+function panic(fmt, ...)
+ error(string.format('error: '..fmt, ...))
+end
+function warn(fmt, ...)
+ io.stderr:write(string.format(fmt..'\n', ...))
+end
+function log(fmt, ...)
+ print(string.format(fmt, ...))
+end
+
+-- Resolver bindings
+kres = require('kres')
+if rawget(kres, 'str2dname') ~= nil then
+ todname = kres.str2dname
+end
+
+-- Compatibility wrapper for query flags.
+worker.resolve = function (qname, qtype, qclass, options, finish, init)
+ -- Alternatively use named arguments
+ if type(qname) == 'table' then
+ local t = qname
+ qname = t.name
+ qtype = t.type or kres.type.A
+ qclass = t.class or kres.class.IN
+ options = t.options
+ finish = t.finish
+ init = t.init
+ end
+
+ local init_cb, finish_cb = init, nil
+ if finish then
+ -- Create callback for finalization
+ finish_cb = ffi.cast('trace_callback_f', function (req)
+ req = kres.request_t(req)
+ finish(req.answer, req)
+ finish_cb:free()
+ end)
+ -- Wrap initialiser to install finish callback
+ init_cb = function (req)
+ req = kres.request_t(req)
+ if init then init(req) end
+ req.trace_finish = finish_cb
+ end
+ end
+
+ -- Translate options and resolve
+ options = kres.mk_qflags(options)
+ return worker.resolve_unwrapped(qname, qtype, qclass, options, init_cb)
+end
+
+resolve = worker.resolve
+
+-- Shorthand for aggregated per-worker information
+worker.info = function ()
+ local t = worker.stats()
+ t.pid = worker.pid
+ return t
+end
+
+-- Resolver mode of operation
+local current_mode = 'normal'
+local mode_table = { normal=0, strict=1, permissive=2 }
+function mode(m)
+ if not m then return current_mode end
+ if not mode_table[m] then error('unsupported mode: '..m) end
+ -- Update current operation mode
+ current_mode = m
+ option('STRICT', current_mode == 'strict')
+ option('PERMISSIVE', current_mode == 'permissive')
+ return true
+end
+
+-- Trivial option alias
+function reorder_RR(val)
+ return option('REORDER_RR', val)
+end
+
+-- Get/set resolver options via name (string)
+function option(name, val)
+ local flags = kres.context().options;
+ -- Note: no way to test existence of flags[name] but we want error anyway.
+ name = string.upper(name) -- convenience
+ if val ~= nil then
+ if (val ~= true) and (val ~= false) then
+ panic('invalid option value: ' .. tostring(val))
+ end
+ flags[name] = val;
+ end
+ return flags[name];
+end
+
+-- Function aliases
+-- `env.VAR returns os.getenv(VAR)`
+env = {}
+setmetatable(env, {
+ __index = function (_, k) return os.getenv(k) end
+})
+
+-- Quick access to interfaces
+-- `net.<iface>` => `net.interfaces()[iface]`
+-- `net = {addr1, ..}` => `net.listen(name, addr1)`
+-- `net.ipv{4,6} = {true, false}` => enable/disable IPv{4,6}
+setmetatable(net, {
+ __index = function (t, k)
+ local v = rawget(t, k)
+ if v then return v
+ elseif k == 'ipv6' then return not option('NO_IPV6')
+ elseif k == 'ipv4' then return not option('NO_IPV4')
+ else return net.interfaces()[k]
+ end
+ end,
+ __newindex = function (t,k,v)
+ if k == 'ipv6' then return option('NO_IPV6', not v)
+ elseif k == 'ipv4' then return option('NO_IPV4', not v)
+ else
+ local iname = rawget(net.interfaces(), v)
+ if iname then t.listen(iname)
+ else t.listen(v)
+ end
+ end
+ end
+})
+
+-- Syntactic sugar for module loading
+-- `modules.<name> = <config>`
+setmetatable(modules, {
+ __newindex = function (_, k, v)
+ if type(k) == 'number' then
+ k, v = v, nil
+ end
+ if not rawget(_G, k) then
+ modules.load(k)
+ k = string.match(k, '[%w_]+')
+ local mod = _G[k]
+ local config = mod and rawget(mod, 'config')
+ if mod ~= nil and config ~= nil then
+ if k ~= v then config(v)
+ else config()
+ end
+ end
+ end
+ end
+})
+
+
+cache.clear = function (name, exact_name, rr_type, chunk_size, callback, prev_state)
+ if name == nil or (name == '.' and not exact_name) then
+ -- keep same output format as for 'standard' clear
+ local total_count = cache.count()
+ if not cache.clear_everything() then
+ error('unable to clear everything')
+ end
+ return {count = total_count}
+ end
+ -- Check parameters, in order, and set defaults if missing.
+ local dname = kres.str2dname(name)
+ if not dname then error('cache.clear(): incorrect name passed') end
+ if exact_name == nil then exact_name = false end
+ if type(exact_name) ~= 'boolean'
+ then error('cache.clear(): incorrect exact_name passed') end
+
+ local cach = kres.context().cache;
+ local rettable = {}
+ -- Apex warning. If the caller passes a custom callback,
+ -- we assume they are advanced enough not to need the check.
+ -- The point is to avoid repeating the check in each callback iteration.
+ if callback == nil then
+ local apex_array = ffi.new('knot_dname_t *[1]') -- C: dname **apex_array
+ local ret = ffi.C.kr_cache_closest_apex(cach, dname, false, apex_array)
+ if ret < 0 then
+ error(ffi.string(ffi.C.knot_strerror(ret))) end
+ if not ffi.C.knot_dname_is_equal(apex_array[0], dname) then
+ local apex_str = kres.dname2str(apex_array[0])
+ rettable.not_apex = 'to clear proofs of non-existence call '
+ .. 'cache.clear(\'' .. tostring(apex_str) ..'\')'
+ rettable.subtree = apex_str
+ end
+ ffi.C.free(apex_array[0])
+ end
+
+ if rr_type ~= nil then
+ -- Special case, without any subtree searching.
+ if not exact_name
+ then error('cache.clear(): specifying rr_type only supported with exact_name') end
+ if chunk_size or callback
+ then error('cache.clear(): chunk_size and callback parameters not supported with rr_type') end
+ local ret = ffi.C.kr_cache_remove(cach, dname, rr_type)
+ if ret < 0 then error(ffi.string(ffi.C.knot_strerror(ret))) end
+ return {count = 1}
+ end
+
+ if chunk_size == nil then chunk_size = 100 end
+ if type(chunk_size) ~= 'number' or chunk_size <= 0
+ then error('cache.clear(): chunk_size has to be a positive integer') end
+
+ -- Do the C call, and add chunk_size warning.
+ rettable.count = ffi.C.kr_cache_remove_subtree(cach, dname, exact_name, chunk_size)
+ if rettable.count == chunk_size then
+ local msg_extra = ''
+ if callback == nil then
+ msg_extra = '; the default callback will continue asynchronously'
+ end
+ rettable.chunk_limit = 'chunk size limit reached' .. msg_extra
+ end
+
+ -- Default callback function: repeat after 1ms
+ if callback == nil then callback =
+ function (cbname, cbexact_name, cbrr_type, cbchunk_size, cbself, cbprev_state, cbrettable)
+ if cbrettable.count < 0 then error(ffi.string(ffi.C.knot_strerror(cbrettable.count))) end
+ if cbprev_state == nil then cbprev_state = { round = 0 } end
+ if type(cbprev_state) ~= 'table'
+ then error('cache.clear() callback: incorrect prev_state passed') end
+ cbrettable.round = cbprev_state.round + 1
+ if (cbrettable.count == cbchunk_size) then
+ event.after(1, function ()
+ cache.clear(cbname, cbexact_name, cbrr_type, cbchunk_size, cbself, cbrettable)
+ end)
+ elseif cbrettable.round > 1 then
+ log('[cache] asynchonous cache.clear(\'' .. cbname .. '\', '
+ .. tostring(cbexact_name) .. ') finished')
+ end
+ return cbrettable
+ end
+ end
+ return callback(name, exact_name, rr_type, chunk_size, callback, prev_state, rettable)
+end
+-- Syntactic sugar for cache
+-- `cache[x] -> cache.get(x)`
+-- `cache.{size|storage} = value`
+setmetatable(cache, {
+ __index = function (t, k)
+ local res = rawget(t, k)
+ if not res and not rawget(t, 'current_size') then return res end
+ -- Beware: t.get returns empty table on failure to find.
+ -- That would be confusing here (breaking kresc), so return nil instead.
+ res = t.get(k)
+ if res and next(res) ~= nil then return res else return nil end
+ end,
+ __newindex = function (t,k,v)
+ -- Defaults
+ local storage = rawget(t, 'current_storage')
+ if not storage then storage = 'lmdb://' end
+ local size = rawget(t, 'current_size')
+ if not size then size = 10*MB end
+ -- Declarative interface for cache
+ if k == 'size' then t.open(v, storage)
+ elseif k == 'storage' then t.open(size, v) end
+ end
+})
+
+-- Register module in Lua environment
+function modules_register(module)
+ -- Syntactic sugar for get() and set() properties
+ setmetatable(module, {
+ __index = function (t, k)
+ local v = rawget(t, k)
+ if v then return v
+ elseif rawget(t, 'get') then return t.get(k)
+ end
+ end,
+ __newindex = function (t, k, v)
+ local old_v = rawget(t, k)
+ if not old_v and rawget(t, 'set') then
+ t.set(k..' '..v)
+ end
+ end
+ })
+end
+
+-- Make sandboxed environment
+local function make_sandbox(defined)
+ local __protected = { worker = true, env = true, modules = true, cache = true, net = true, trust_anchors = true }
+
+ -- Compute and export the list of top-level names (hidden otherwise)
+ local nl = ""
+ for n in pairs(defined) do
+ nl = nl .. n .. "\n"
+ end
+
+ return setmetatable({ __orig_name_list = nl }, {
+ __index = defined,
+ __newindex = function (_, k, v)
+ if __protected[k] then
+ for k2,v2 in pairs(v) do
+ defined[k][k2] = v2
+ end
+ else
+ defined[k] = v
+ end
+ end
+ })
+end
+
+-- Compatibility sandbox
+if setfenv then -- Lua 5.1 and less
+ _G = make_sandbox(getfenv(0))
+ setfenv(0, _G)
+else -- Lua 5.2+
+ _SANDBOX = make_sandbox(_ENV)
+end
+
+-- Load embedded modules
+trust_anchors = require('trust_anchors')
+modules.load('ta_signal_query')
+modules.load('policy')
+modules.load('priming')
+modules.load('detect_time_skew')
+modules.load('detect_time_jump')
+modules.load('ta_sentinel')
+modules.load('edns_keepalive')
+
+-- Interactive command evaluation
+function eval_cmd(line, raw)
+ -- Compatibility sandbox code loading
+ local function load_code(code)
+ if getfenv then -- Lua 5.1
+ return loadstring(code)
+ else -- Lua 5.2+
+ return load(code, nil, 't', _ENV)
+ end
+ end
+ local err, chunk
+ chunk, err = load_code(raw and 'return '..line or 'return table_print('..line..')')
+ if err then
+ chunk, err = load_code(line)
+ end
+ if not err then
+ return chunk()
+ else
+ error(err)
+ end
+end
+
+-- Pretty printing
+function table_print (tt, indent, done)
+ done = done or {}
+ indent = indent or 0
+ local result = ""
+ -- Convert to printable string (escape unprintable)
+ local function printable(value)
+ value = tostring(value)
+ local bytes = {}
+ for i = 1, #value do
+ local c = string.byte(value, i)
+ if c >= 0x20 and c < 0x7f then table.insert(bytes, string.char(c))
+ else table.insert(bytes, '\\'..tostring(c))
+ end
+ if i > 80 then table.insert(bytes, '...') break end
+ end
+ return table.concat(bytes)
+ end
+ if type(tt) == "table" then
+ for key, value in pairs (tt) do
+ result = result .. string.rep (" ", indent)
+ if type (value) == "table" and not done [value] then
+ done [value] = true
+ result = result .. string.format("[%s] => {\n", printable (key))
+ result = result .. table_print (value, indent + 4, done)
+ result = result .. string.rep (" ", indent)
+ result = result .. "}\n"
+ else
+ result = result .. string.format("[%s] => %s\n",
+ tostring (key), printable(value))
+ end
+ end
+ else
+ result = result .. tostring(tt) .. "\n"
+ end
+ return result
+end
+
+-- This extends the worker module to allow asynchronous execution of functions and nonblocking I/O.
+-- The current implementation combines cqueues for Lua interface, and event.socket() in order to not
+-- block resolver engine while waiting for I/O or timers.
+--
+local has_cqueues, cqueues = pcall(require, 'cqueues')
+if has_cqueues then
+
+ -- Export the asynchronous sleep function
+ worker.sleep = cqueues.sleep
+
+ -- Create metatable for workers to define the API
+ -- It can schedule multiple cqueues and yield execution when there's a wait for blocking I/O or timer
+ local asynchronous_worker_mt = {
+ work = function (self)
+ local ok, err, _, co = self.cq:step(0)
+ if not ok then
+ warn('[%s] error: %s %s', self.name or 'worker', err, debug.traceback(co))
+ end
+ -- Reschedule timeout or create new one
+ local timeout = self.cq:timeout()
+ if timeout then
+ -- Throttle timeouts to avoid too frequent wakeups
+ if timeout == 0 then timeout = 0.00001 end
+ -- Convert from seconds to duration
+ timeout = timeout * sec
+ if not self.next_timeout then
+ self.next_timeout = event.after(timeout, self.on_step)
+ else
+ event.reschedule(self.next_timeout, timeout)
+ end
+ else -- Cancel running timeout when there is no next deadline
+ if self.next_timeout then
+ event.cancel(self.next_timeout)
+ self.next_timeout = nil
+ end
+ end
+ end,
+ wrap = function (self, f)
+ self.cq:wrap(f)
+ end,
+ loop = function (self)
+ self.on_step = function () self:work() end
+ self.event_fd = event.socket(self.cq:pollfd(), self.on_step)
+ end,
+ close = function (self)
+ if self.event_fd then
+ event.cancel(self.event_fd)
+ self.event_fd = nil
+ end
+ end,
+ }
+
+ -- Implement the coroutine worker with cqueues
+ local function worker_new (name)
+ return setmetatable({name = name, cq = cqueues.new()}, { __index = asynchronous_worker_mt })
+ end
+
+ -- Create a default background worker
+ worker.bg_worker = worker_new('worker.background')
+ worker.bg_worker:loop()
+
+ -- Wrap a function for asynchronous execution
+ function worker.coroutine (f)
+ worker.bg_worker:wrap(f)
+ end
+else
+ -- Disable asynchronous execution
+ local function disabled () error('cqueues are required for asynchronous execution') end
+ worker.sleep = disabled
+ worker.map = disabled
+ worker.coroutine = disabled
+end
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-18 19:04:13 +0000