💾 Archived View for gemini.conman.org › sourcecode › Lua › GLV-1 › handlers › filesystem.lua captured on 2020-11-01 at 00:00:48.
-=-=-=-=-=-=-
-- ************************************************************************
--
-- The file system handler
-- Copyright 2019 by Sean Conner. All Rights Reserved.
--
-- This program is free software: you can redistribute it and/or modify
-- it under the terms of the GNU General Public License as published by
-- the Free Software Foundation, either version 3 of the License, or
-- (at your option) any later version.
--
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-- GNU General Public License for more details.
--
-- You should have received a copy of the GNU General Public License
-- along with this program. If not, see <http://www.gnu.org/licenses/>.
--
-- Comments, questions and criticisms can be sent to: sean@conman.org
--
-- ************************************************************************
-- luacheck: globals init handler
-- luacheck: ignore 611
local syslog = require "org.conman.syslog"
local errno = require "org.conman.errno"
local fsys = require "org.conman.fsys"
local magic = require "org.conman.fsys.magic"
local uurl = require "GLV-1.url-util"
local MSG = require "GLV-1.MSG"
local cgi = require "GLV-1.cgi"
local scgi = require "GLV-1.scgi"
local io = require "io"
local string = require "string"
local table = require "table"
local ipairs = ipairs
local pairs = pairs
_ENV = {}
-- ************************************************************************
function init(iconf,hconf,gconf)
iconf.index = iconf.index
or hconf.index
or gconf.index
or "index.gemini"
iconf.no_access = iconf.no_access
or hconf.no_access
or gconf.no_access
or { "^%." }
iconf.extension = iconf.extension
or hconf.extension
or gconf.extension
or ".gemini"
local gmime = gconf.mime or {}
local hmime = hconf.mime or {}
for ext,mimetype in pairs(gmime) do
if hmime[ext] == nil then
hmime[ext] = mimetype
end
end
if not iconf.mime then
iconf.mime = hmime
else
for ext,mimetype in pairs(hmime) do
if iconf.mime[ext] == nil then
iconf.mime[ext] = mimetype
end
end
end
do
local ext = iconf.extension:sub(2,-1)
if iconf.mime[ext] then
if iconf.mime[ext] ~= 'text/gemini' then
syslog('warning',"overriding existing MIME type for .%s",ext)
iconf.mime[ext] = 'text/gemini'
end
else
iconf.mime[ext] = 'text/gemini'
end
end
return true
end
-- ************************************************************************
local function descend_path(path)
local function iter(state,var)
local n = state()
if n then
return var .. "/" .. n,n
end
end
return iter,path:gmatch("[^/]+"),"."
end
-- ************************************************************************
function handler(conf,auth,loc,match)
local function read_file(file,base)
local function contents(mime)
if mime == "" then
syslog('warning',"%s: missing MIME type",file)
mime = 'text/plain'
end
local f,err = io.open(file,"rb")
if not f then
syslog('error',"%s: %s",file,err)
return 40,MSG[40],""
end
local data = f:read("*a")
f:close()
return 20,mime,data
end
if fsys.access(file,"rx") then
return cgi(auth,file,conf,base,loc)
end
if not fsys.access(file,"r") then
return 51,MSG[51],""
end
-- ---------------------------------------------------------------------
-- Check to see if we're at the end of the request. If we're not, then
-- the client is buggy or tolling us, so return an error.
-- ---------------------------------------------------------------------
local _,e = loc.path:find(fsys.basename(file),1,true)
local pathinfo = e and loc.path:sub(e+1,-1) or loc.path
if e and pathinfo ~= "" then
return 51,MSG[51],""
end
return contents(conf.mime[fsys.extension(file)] or magic(file))
end
-- ----------------------------------------------------------------------
-- To keep thing simple, we still support the older method of specifying
-- the path with a single match. This may change in the future, but for
-- now, let's do this.
-- ----------------------------------------------------------------------
if #match == 1 then
match[1],match[2] = match[1]:match("^(/)(.*)")
end
for dir,segment in descend_path(match[2]) do
-- ----------------------------------------------------
-- Skip the following files that match these patterns
-- ----------------------------------------------------
for _,pattern in ipairs(conf.no_access) do
if segment:match(pattern) then
return 51,MSG[51],""
end
end
local name = conf.directory .. "/" .. dir
local info,err = fsys.lstat(name)
if not info then
syslog('error',"fsys.stat(%q) = %s",name,errno[err])
return 51,MSG[51],""
end
if info.mode.type == 'dir' then
-- -------------------------------------------
-- Do we have an issue with Unix permissions?
-- -------------------------------------------
if not fsys.access(name,"x") then
syslog('error',"access(%q) failed",dir)
return 51,MSG[51],""
end
elseif info.mode.type == 'file' then
local _,e = loc.path:find(segment,1,true)
local base = loc.path:sub(1,e)
return read_file(name,base)
elseif info.mode.type == 'link' then
local _,e = loc.path:find(segment,1,true)
local base = loc.path:sub(1,e)
return scgi(auth,name,conf,base,loc)
else
return 51,MSG[51],""
end
end
-- ----------------------------------------------------------------------
-- Because I'm that pedantic---if we get here, we at a directory. If the
-- passed in request did NOT end in a '/', do a permanent redirect to a
-- request WITH a final '/'. This is to ensure any mistakes with covering
-- a directory in the authorization block doesn't fail because the user
-- included a trailing '/' in the pattern ...
-- ----------------------------------------------------------------------
if not loc.path:match "/$" then
return 31,uurl.esc_path:match(loc.path .. "/"),""
end
-- ------------------------
-- Check for an index file
-- ------------------------
local final = conf.directory .. "/" .. match[2]
if fsys.access(final .. "/" .. conf.index,"r") then
return read_file(final .. "/" .. conf.index)
end
-- --------------------------------------------
-- Nope, one doesn't exist, so let's build one
-- --------------------------------------------
local res =
{
string.format("Index of %s",match[2]),
"---------------------------",
""
}
local function access_okay(dir,entry)
for _,pattern in ipairs(conf.no_access) do
if entry:match(pattern) then return false end
end
local fname = dir .. "/" .. entry
local info = fsys.lstat(fname)
if not info then
return false
elseif info.mode.type == 'file' then
if fsys.access(fname,'rx') then
return true,'file','CGI script'
else
return fsys.access(fname,"r"),'file',string.format("%d bytes",info.size)
end
elseif info.mode.type == 'dir' then
return fsys.access(fname,"x"),'dir'
elseif info.mode.type == 'link' then
return true,'file','SCGI script'
else
return false
end
end
local lists =
{
dir = {},
file = {},
}
for entry in fsys.dir(final) do
local okay,type,meta = access_okay(final,entry)
if okay then
table.insert(lists[type],{ name = entry , meta = meta })
end
end
table.sort(lists.dir, function(a,b) return a.name < b.name end)
table.sort(lists.file,function(a,b) return a.name < b.name end)
for _,entry in ipairs(lists.dir) do
table.insert(res,string.format("=> %s/\t%s/",uurl.esc_path:match(entry.name),entry.name))
end
if #lists.dir > 0 then
table.insert(res,"")
end
for _,entry in ipairs(lists.file) do
table.insert(res,string.format("=> %s\t%s (%s)",uurl.esc_path:match(entry.name),entry.name,entry.meta))
end
table.insert(res,"")
table.insert(res,"---------------------------")
table.insert(res,"GLV-1.12556")
return 20,"text/gemini",table.concat(res,"\r\n") .. "\r\n"
end
-- ************************************************************************
return _ENV