in-memory wip

2 files changed, 531 insertions, 47 deletions

diff --git a/json.lua b/json.lua
new file mode 100644
index 0000000..711ef78
--- /dev/null
+++ b/json.lua
@@ -0,0 +1,388 @@
+--
+-- json.lua
+--
+-- Copyright (c) 2020 rxi
+--
+-- Permission is hereby granted, free of charge, to any person obtaining a copy of
+-- this software and associated documentation files (the "Software"), to deal in
+-- the Software without restriction, including without limitation the rights to
+-- use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+-- of the Software, and to permit persons to whom the Software is furnished to do
+-- so, subject to the following conditions:
+--
+-- The above copyright notice and this permission notice shall be included in all
+-- copies or substantial portions of the Software.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+-- SOFTWARE.
+--
+
+local json = { _version = "0.1.2" }
+
+-------------------------------------------------------------------------------
+-- Encode
+-------------------------------------------------------------------------------
+
+local encode
+
+local escape_char_map = {
+  [ "\\" ] = "\\",
+  [ "\"" ] = "\"",
+  [ "\b" ] = "b",
+  [ "\f" ] = "f",
+  [ "\n" ] = "n",
+  [ "\r" ] = "r",
+  [ "\t" ] = "t",
+}
+
+local escape_char_map_inv = { [ "/" ] = "/" }
+for k, v in pairs(escape_char_map) do
+  escape_char_map_inv[v] = k
+end
+
+
+local function escape_char(c)
+  return "\\" .. (escape_char_map[c] or string.format("u%04x", c:byte()))
+end
+
+
+local function encode_nil(val)
+  return "null"
+end
+
+
+local function encode_table(val, stack)
+  local res = {}
+  stack = stack or {}
+
+  -- Circular reference?
+  if stack[val] then error("circular reference") end
+
+  stack[val] = true
+
+  if rawget(val, 1) ~= nil or next(val) == nil then
+    -- Treat as array -- check keys are valid and it is not sparse
+    local n = 0
+    for k in pairs(val) do
+      if type(k) ~= "number" then
+        error("invalid table: mixed or invalid key types")
+      end
+      n = n + 1
+    end
+    if n ~= #val then
+      error("invalid table: sparse array")
+    end
+    -- Encode
+    for i, v in ipairs(val) do
+      table.insert(res, encode(v, stack))
+    end
+    stack[val] = nil
+    return "[" .. table.concat(res, ",") .. "]"
+
+  else
+    -- Treat as an object
+    for k, v in pairs(val) do
+      if type(k) ~= "string" then
+        error("invalid table: mixed or invalid key types")
+      end
+      table.insert(res, encode(k, stack) .. ":" .. encode(v, stack))
+    end
+    stack[val] = nil
+    return "{" .. table.concat(res, ",") .. "}"
+  end
+end
+
+
+local function encode_string(val)
+  return '"' .. val:gsub('[%z\1-\31\\"]', escape_char) .. '"'
+end
+
+
+local function encode_number(val)
+  -- Check for NaN, -inf and inf
+  if val ~= val or val <= -math.huge or val >= math.huge then
+    error("unexpected number value '" .. tostring(val) .. "'")
+  end
+  return string.format("%.14g", val)
+end
+
+
+local type_func_map = {
+  [ "nil"     ] = encode_nil,
+  [ "table"   ] = encode_table,
+  [ "string"  ] = encode_string,
+  [ "number"  ] = encode_number,
+  [ "boolean" ] = tostring,
+}
+
+
+encode = function(val, stack)
+  local t = type(val)
+  local f = type_func_map[t]
+  if f then
+    return f(val, stack)
+  end
+  error("unexpected type '" .. t .. "'")
+end
+
+
+function json.encode(val)
+  return ( encode(val) )
+end
+
+
+-------------------------------------------------------------------------------
+-- Decode
+-------------------------------------------------------------------------------
+
+local parse
+
+local function create_set(...)
+  local res = {}
+  for i = 1, select("#", ...) do
+    res[ select(i, ...) ] = true
+  end
+  return res
+end
+
+local space_chars   = create_set(" ", "\t", "\r", "\n")
+local delim_chars   = create_set(" ", "\t", "\r", "\n", "]", "}", ",")
+local escape_chars  = create_set("\\", "/", '"', "b", "f", "n", "r", "t", "u")
+local literals      = create_set("true", "false", "null")
+
+local literal_map = {
+  [ "true"  ] = true,
+  [ "false" ] = false,
+  [ "null"  ] = nil,
+}
+
+
+local function next_char(str, idx, set, negate)
+  for i = idx, #str do
+    if set[str:sub(i, i)] ~= negate then
+      return i
+    end
+  end
+  return #str + 1
+end
+
+
+local function decode_error(str, idx, msg)
+  local line_count = 1
+  local col_count = 1
+  for i = 1, idx - 1 do
+    col_count = col_count + 1
+    if str:sub(i, i) == "\n" then
+      line_count = line_count + 1
+      col_count = 1
+    end
+  end
+  error( string.format("%s at line %d col %d", msg, line_count, col_count) )
+end
+
+
+local function codepoint_to_utf8(n)
+  -- http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=iws-appendixa
+  local f = math.floor
+  if n <= 0x7f then
+    return string.char(n)
+  elseif n <= 0x7ff then
+    return string.char(f(n / 64) + 192, n % 64 + 128)
+  elseif n <= 0xffff then
+    return string.char(f(n / 4096) + 224, f(n % 4096 / 64) + 128, n % 64 + 128)
+  elseif n <= 0x10ffff then
+    return string.char(f(n / 262144) + 240, f(n % 262144 / 4096) + 128,
+                       f(n % 4096 / 64) + 128, n % 64 + 128)
+  end
+  error( string.format("invalid unicode codepoint '%x'", n) )
+end
+
+
+local function parse_unicode_escape(s)
+  local n1 = tonumber( s:sub(1, 4),  16 )
+  local n2 = tonumber( s:sub(7, 10), 16 )
+   -- Surrogate pair?
+  if n2 then
+    return codepoint_to_utf8((n1 - 0xd800) * 0x400 + (n2 - 0xdc00) + 0x10000)
+  else
+    return codepoint_to_utf8(n1)
+  end
+end
+
+
+local function parse_string(str, i)
+  local res = ""
+  local j = i + 1
+  local k = j
+
+  while j <= #str do
+    local x = str:byte(j)
+
+    if x < 32 then
+      decode_error(str, j, "control character in string")
+
+    elseif x == 92 then -- `\`: Escape
+      res = res .. str:sub(k, j - 1)
+      j = j + 1
+      local c = str:sub(j, j)
+      if c == "u" then
+        local hex = str:match("^[dD][89aAbB]%x%x\\u%x%x%x%x", j + 1)
+                 or str:match("^%x%x%x%x", j + 1)
+                 or decode_error(str, j - 1, "invalid unicode escape in string")
+        res = res .. parse_unicode_escape(hex)
+        j = j + #hex
+      else
+        if not escape_chars[c] then
+          decode_error(str, j - 1, "invalid escape char '" .. c .. "' in string")
+        end
+        res = res .. escape_char_map_inv[c]
+      end
+      k = j + 1
+
+    elseif x == 34 then -- `"`: End of string
+      res = res .. str:sub(k, j - 1)
+      return res, j + 1
+    end
+
+    j = j + 1
+  end
+
+  decode_error(str, i, "expected closing quote for string")
+end
+
+
+local function parse_number(str, i)
+  local x = next_char(str, i, delim_chars)
+  local s = str:sub(i, x - 1)
+  local n = tonumber(s)
+  if not n then
+    decode_error(str, i, "invalid number '" .. s .. "'")
+  end
+  return n, x
+end
+
+
+local function parse_literal(str, i)
+  local x = next_char(str, i, delim_chars)
+  local word = str:sub(i, x - 1)
+  if not literals[word] then
+    decode_error(str, i, "invalid literal '" .. word .. "'")
+  end
+  return literal_map[word], x
+end
+
+
+local function parse_array(str, i)
+  local res = {}
+  local n = 1
+  i = i + 1
+  while 1 do
+    local x
+    i = next_char(str, i, space_chars, true)
+    -- Empty / end of array?
+    if str:sub(i, i) == "]" then
+      i = i + 1
+      break
+    end
+    -- Read token
+    x, i = parse(str, i)
+    res[n] = x
+    n = n + 1
+    -- Next token
+    i = next_char(str, i, space_chars, true)
+    local chr = str:sub(i, i)
+    i = i + 1
+    if chr == "]" then break end
+    if chr ~= "," then decode_error(str, i, "expected ']' or ','") end
+  end
+  return res, i
+end
+
+
+local function parse_object(str, i)
+  local res = {}
+  i = i + 1
+  while 1 do
+    local key, val
+    i = next_char(str, i, space_chars, true)
+    -- Empty / end of object?
+    if str:sub(i, i) == "}" then
+      i = i + 1
+      break
+    end
+    -- Read key
+    if str:sub(i, i) ~= '"' then
+      decode_error(str, i, "expected string for key")
+    end
+    key, i = parse(str, i)
+    -- Read ':' delimiter
+    i = next_char(str, i, space_chars, true)
+    if str:sub(i, i) ~= ":" then
+      decode_error(str, i, "expected ':' after key")
+    end
+    i = next_char(str, i + 1, space_chars, true)
+    -- Read value
+    val, i = parse(str, i)
+    -- Set
+    res[key] = val
+    -- Next token
+    i = next_char(str, i, space_chars, true)
+    local chr = str:sub(i, i)
+    i = i + 1
+    if chr == "}" then break end
+    if chr ~= "," then decode_error(str, i, "expected '}' or ','") end
+  end
+  return res, i
+end
+
+
+local char_func_map = {
+  [ '"' ] = parse_string,
+  [ "0" ] = parse_number,
+  [ "1" ] = parse_number,
+  [ "2" ] = parse_number,
+  [ "3" ] = parse_number,
+  [ "4" ] = parse_number,
+  [ "5" ] = parse_number,
+  [ "6" ] = parse_number,
+  [ "7" ] = parse_number,
+  [ "8" ] = parse_number,
+  [ "9" ] = parse_number,
+  [ "-" ] = parse_number,
+  [ "t" ] = parse_literal,
+  [ "f" ] = parse_literal,
+  [ "n" ] = parse_literal,
+  [ "[" ] = parse_array,
+  [ "{" ] = parse_object,
+}
+
+
+parse = function(str, idx)
+  local chr = str:sub(idx, idx)
+  local f = char_func_map[chr]
+  if f then
+    return f(str, idx)
+  end
+  decode_error(str, idx, "unexpected character '" .. chr .. "'")
+end
+
+
+function json.decode(str)
+  if type(str) ~= "string" then
+    error("expected argument of type string, got " .. type(str))
+  end
+  local res, idx = parse(str, next_char(str, 1, space_chars, true))
+  idx = next_char(str, idx, space_chars, true)
+  if idx <= #str then
+    decode_error(str, idx, "trailing garbage")
+  end
+  return res
+end
+
+
+return json
diff --git a/lclipd.lua b/lclipd.lua
index 7dcddba..bba5c05 100755
--- a/lclipd.lua
+++ b/lclipd.lua
@@ -4,11 +4,11 @@
 -- luarocks-5.3 install --local luaposix
 -- luarocks-5.3 install --local argparse
 -- luarocks-5.3 install --local lsqlite3
--- front-end example: sqlite3 $(cat /tmp/lclipd/lclipd_db_name) 'select content from lclipd;' | dmenu -l 10 | xsel -ib
+-- pipx install detect-secrets
 local string = require("string")
 
--- Adds the lua rocks modules to the require path for this script
-local function default_luarocks_modules()
+--- Adds LUA_PATH and LUA_CPATH to the current interpreters path.
+local function add_luarocks_modules()
     local luarocks_handle = io.popen("luarocks-5.3 path --bin")
     local path_b = false
     local cpath_b = false
@@ -26,7 +26,7 @@ local function default_luarocks_modules()
     if path_b then os.exit(1) end
     if cpath_b then os.exit(1) end
 end
-default_luarocks_modules()
+add_luarocks_modules()
 
 -- we want to delete a pidfile if we wrote one, otherwise we won't
 local wrote_a_pidfile = false
@@ -38,6 +38,14 @@ local unistd = require("posix.unistd")
 local posix_syslog = require("posix.syslog")
 local sqlite3 = require("lsqlite3")
 local posix_wait = require("posix.sys.wait")
+local posix_socket = require("posix.sys.socket")
+local libgen = require("posix.libgen")
+
+-- vendored dependency
+-- https://github.com/rxi/json.lua
+local base_path = libgen.dirname(arg[0])
+package.path = package.path .. ";" .. base_path .. "/?.lua"
+local json = require("json")
 
 local sql_create_table = [=[
 create table if not exists lclipd (
@@ -70,20 +78,17 @@ insert into lclipd(content,dateAdded) values('%s', unixepoch());
 
 -- using a heredoc string without expansion bypasses the need for escaping
 local detect_secrets_cmd = [=[
-detect-secrets scan %s --string <<- STR | grep -v False
+detect-secrets scan %s --string <<- STR | grep True
 %s
 STR
 ]=]
 
 local tmp_dir = "/tmp/lclipd"
 local pid_file = "/tmp/lclipd/lclipd.pid"
-local db_file_name = "/tmp/lclipd/lclipd_db_name"
 
 --- We are not longer running.
 local function remove_pid_file() if wrote_a_pidfile then os.remove(pid_file) end end
 
---- Adds LUA_PATH and LUA_CPATH to the current interpreters path.
-
 local function lclip_exit(n)
     os.exit(n)
     remove_pid_file()
@@ -94,6 +99,8 @@ parser:option("-s --hist_size",
               "number of distinct entries for clipboard history", 200)
 parser:option("-d --detect_secrets_args",
               "options that will be passed to detect secrets", "")
+parser:option("-a --address", "address to bind to", "127.0.0.1")
+parser:option("-p --port", "port to bind to", 9999)
 
 --- Log the given string to syslog with the given priority.
 -- @param log_str the string passed to the logging facility
@@ -114,16 +121,6 @@ local function check_uid_gid()
                   posix_syslog.LOG_INFO)
 end
 
---- Change the permission to user read/write i.e. chmod 600
--- @param path to the database file whose permissions will be set
-local function set_db_permissions(db_path)
-    local ret = sys_stat.chmod(db_path, sys_stat.S_IRUSR | sys_stat.S_IWUSR)
-    if ret ~= 0 then
-        log_to_syslog(tostring(ret), posix_syslog.LOG_CRIT)
-        lclip_exit(1)
-    end
-end
-
 --- Creates the necessary dirs
 local function make_tmp_dirs()
     local f = sys_stat.stat(tmp_dir)
@@ -210,12 +207,11 @@ local function detect_secrets(clipboard_content, detect_secrets_args)
         unistd.close(pipe_read)
         local cmd = string.format(detect_secrets_cmd, detect_secrets_args,
                                   clipboard_content)
-        local _, secrets_baseline_handle = pcall(io.popen, cmd)
-        local secrets_baseline = secrets_baseline_handle:read("*a")
-        if secrets_baseline == "" then
-            unistd.write(pipe_write, "1")
-        else
+        local ret = os.execute(cmd)
+        if ret == 0 then
             unistd.write(pipe_write, "0")
+        else
+            unistd.write(pipe_write, "1")
         end
 
         unistd.close(pipe_write)
@@ -258,6 +254,7 @@ local function get_clipboard_content()
         local _, handle_x = pcall(io.popen, "xsel -ob")
         if handle_x ~= nil then
             local last_clip_entry_x = handle_x:read("*a")
+            handle_x:close()
             if last_clip_entry_x ~= "" and last_clip_entry_x ~= nil then
                 return last_clip_entry_x
             end
@@ -266,6 +263,7 @@ local function get_clipboard_content()
         local _, handle_w = pcall(io.popen, "wl-paste")
         if handle_w ~= nil then
             local last_clip_entry_w = handle_w:read("*a")
+            handle_w:close()
             if last_clip_entry_w ~= "" and last_clip_entry_w ~= nil then
                 return last_clip_entry_w
             end
@@ -277,33 +275,122 @@ end
 
 --- Get the sqlite DB handle.
 local function get_sqlite_handle()
-    local tmp_db_name = "/tmp/" ..
-                            io.popen(
-                                "tr -dc A-Za-z0-9 </dev/urandom | head -c 17"):read(
-                                "*a")
-    log_to_syslog(tmp_db_name, posix_syslog.LOG_INFO)
-    local clipDB = sqlite3.open(tmp_db_name,
-                                sqlite3.OPEN_READWRITE + sqlite3.OPEN_CREATE)
+    local clipDB = sqlite3.open("/dev/shm/lclipd")
+    -- local clipDB = sqlite3.open("")
     if clipDB == nil then
         log_to_syslog("could not open the database", posix_syslog.LOG_CRIT)
         lclip_exit(1)
     end
-    set_db_permissions(tmp_db_name)
-
-    local tmp_db_file = io.open(db_file_name, "w")
-    local stdout = io.output()
-    io.output(tmp_db_file)
-    io.write(tmp_db_name .. "\n")
-    io.close(tmp_db_file)
-    io.output(stdout)
 
     return clipDB
 end
 
+--- Callback function to get the result when we receive a query from the socket
+local function server_query_callback(conn, columns, values, _)
+    local result_table = {}
+    for i = 1, columns do result_table[i] = values[i] end
+
+    local result_json = json.encode(result_table)
+
+    local bytes_sent, errmsg = posix_socket.send(conn, result_json)
+    if bytes_sent == nil then
+        log_to_syslog(errmsg, posix_syslog.LOG_WARNING)
+        unistd._exit(1)
+    end
+    return 0
+end
+
+--- Start the lclipd server
+-- @param bind_address
+-- @param bind_port
+local function run_server(bind_address, bind_port, sqlite_handle)
+    local server_pid, errmsg = unistd.fork()
+    if server_pid == nil then -- error
+        log_to_syslog(errmsg, posix_syslog.LOG_CRIT)
+        lclip_exit(1)
+    elseif server_pid == 0 then -- child
+        log_to_syslog("server component forked", posix_syslog.LOG_INFO)
+        local sock, errmsg = posix_socket.socket(posix_socket.AF_INET,
+                                                 posix_socket.SOCK_STREAM, 0)
+        if sock == nil then
+            log_to_syslog(errmsg, posix_syslog.LOG_CRIT)
+            lclip_exit(1)
+        end
+
+        local ret, errmsg = posix_socket.bind(sock, {
+            port = bind_port,
+            addr = bind_address,
+            family = posix_socket.AF_INET,
+            socktype = posix_socket.SOCK_STREAM
+        })
+        if ret == nil then
+            log_to_syslog(errmsg, posix_syslog.LOG_CRIT)
+            lclip_exit(1)
+        end
+
+        ret, errmsg = posix_socket.listen(sock, posix_socket.SOMAXCONN)
+        if ret == nil then
+            log_to_syslog(errmsg, posix_syslog.LOG_CRIT)
+            lclip_exit(1)
+        end
+        log_to_syslog("listening on " .. bind_address .. ":" ..
+                          tostring(bind_port), posix_syslog.LOG_INFO)
+
+        while true do
+            local conn, conn_addr = posix_socket.accept(sock)
+            if conn == nil then
+                log_to_syslog(conn_addr, posix_syslog.LOG_CRIT)
+                lclip_exit(1)
+            end
+
+            -- we fork on every incoming connection
+            local pid, errmsg = unistd.fork() -- connection fork
+            if pid == nil then -- error
+                log_to_syslog(errmsg, posix_syslog.LOG_WARNING)
+            elseif pid == 0 then -- child
+                local msg = {}
+                log_to_syslog("forked on incoming connection",
+                              posix_syslog.LOG_INFO)
+                while true do
+                    local b = posix_socket.recv(conn, 2 ^ 14)
+                    if not b or #b == 0 then break end
+                    table.insert(msg, b)
+                end
+                if msg == nil then
+                    log_to_syslog(errmsg, posix_syslog.LOG_WARNING)
+                    unistd.close(conn)
+                    unistd._exit(1)
+                end
+                msg = table.concat(msg)
+                log_to_syslog(msg, posix_syslog.LOG_INFO)
+                local return_code = sqlite_handle:exec(msg,
+                                                       server_query_callback,
+                                                       conn)
+                if return_code ~= sqlite3.OK then
+                    log_to_syslog(tostring(return_code),
+                                  posix_syslog.LOG_WARNING)
+                    unistd.close(conn)
+                    unistd._exit(1)
+                end
+                unistd.close(conn)
+                unistd._exit(0)
+                -- nothing to do for the parent here, we want the parent to return
+                -- and wait on accept for a new incoming connection
+            end
+            unistd.close(conn)
+        end
+    elseif server_pid > 0 then -- parent
+        -- the parent process can just return at this point
+        -- we are simply achieving asynchronicity with this
+        -- for the server component
+        return
+    end
+end
+
 --- The clipboard's main loop
 -- @param clip_hist_size number of entries limit for the clip history file
 -- @param detect_secrets_artgs args to pass to detect-secrets scan
-local function loop(clip_hist_size, detect_secrets_args)
+local function loop(args)
     local sqlite_handle = get_sqlite_handle()
 
     -- create the table if it does not exist
@@ -315,7 +402,8 @@ local function loop(clip_hist_size, detect_secrets_args)
     end
 
     -- add the old_reap trigger
-    sql_old_reap_trigger = string.format(sql_old_reap_trigger, clip_hist_size)
+    sql_old_reap_trigger =
+        string.format(sql_old_reap_trigger, args["hist_size"])
     return_code = sqlite_handle:exec(sql_old_reap_trigger)
     if return_code ~= sqlite3.OK then
         log_to_syslog(tostring(return_code), posix_syslog.LOG_CRIT)
@@ -324,6 +412,9 @@ local function loop(clip_hist_size, detect_secrets_args)
         lclip_exit(1)
     end
 
+    -- fork the server component and give control back to the clipboard
+    run_server(args["address"], args["port"], sqlite_handle)
+
     log_to_syslog("starting the main loop", posix_syslog.LOG_INFO)
     while true do
         local clip_content = get_clipboard_content()
@@ -334,11 +425,11 @@ local function loop(clip_hist_size, detect_secrets_args)
         if clip_content == nil then goto continue end
         local insert_string = string.format(sql_insert, clip_content)
 
-        if detect_secrets(clip_content, detect_secrets_args) then
-            sqlite_handle:exec(insert_string)
-        end
-        if return_code ~= sqlite3.OK then
-            log_to_syslog(tostring(return_code), posix_syslog.LOG_WARNING)
+        if detect_secrets(clip_content, args["detect_secrets_args"]) then
+            return_code = sqlite_handle:exec(insert_string)
+            if return_code ~= sqlite3.OK then
+                log_to_syslog(tostring(return_code), posix_syslog.LOG_WARNING)
+            end
         end
         ::continue::
     end
@@ -356,14 +447,19 @@ local function main()
         io.write("\n")
         os.exit(128 + signum)
     end)
+    -- we reap dead processes so we dont end up with zombies all over.
+    -- in our case, we dont really care how a child is terminated as
+    -- long as it terminates.
+    -- signal.signal(signal.SIGCHILD, function(_)
+    --     while posix_wait.wait(-1, posix_wait.WNOHANG) > 0 do end
+    -- end)
 
     make_tmp_dirs()
     local args = parser:parse()
     check_pid_file()
     write_pid_file()
     check_uid_gid()
-    local status, err = pcall(loop, args["hist_size"],
-                              args["detect_secrets_args"])
+    local status, err = pcall(loop, args)
     if status ~= true then log_to_syslog(err, posix_syslog.LOG_CRIT) end
 end