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diff --git a/hugo-authentication.lua b/hugo-authentication.lua
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+-- This script may be used with the auth-filter. Be sure to configure it as you wish.
+--
+-- Requirements:
+-- 	luacrypto >= 0.3
+-- 	<http://mkottman.github.io/luacrypto/>
+--
+
+
+--
+--
+-- Configure these variables for your settings.
+--
+--
+
+-- A list of password protected repositories along with the users who can access them.
+local public_repos = {
+    vimwiki = true
+}
+
+-- Please note that, in production, you'll want to replace this simple lookup
+-- table with either a table of salted and hashed passwords (using something
+-- smart like scrypt), or replace this table lookup with an external support,
+-- such as consulting your system's pam / shadow system, or an external
+-- database, or an external validating web service. For testing, or for
+-- extremely low-security usage, you may be able, however, to get away with
+-- compromising on hardcoding the passwords in cleartext, as we have done here.
+local users = {
+    hugo = "password"
+}
+
+-- All cookies will be authenticated based on this secret. Make it something
+-- totally random and impossible to guess. It should be large.
+local secret = "Ianae4woof3ial9ahdahng7ahth9yoo2ri6zuw7eeYaengai0s"
+
+
+--
+--
+-- Authentication functions follow below. Swap these out if you want different authentication semantics.
+--
+--
+
+function printenv(arg)
+	local keys = {
+		"CGIT_CONFIG",
+		"CGIT_REPO_URL", "CGIT_REPO_NAME", "CGIT_REPO_PATH",
+		"CGIT_REPO_OWNER", "CGIT_REPO_GROUP", "CGIT_REPO_DEFBRANCH",
+		"CGIT_REPO_SECTION", "CGIT_REPO_CLONE_URL",
+
+		"GIT_REPO", "GIT_CONFIG_NOSYSTEM",
+		"GIT_ATTR_NOSYSTEM",
+		"GIT_DIR", "GIT_CONFIG_NOSYSTEM", "GIT_ATTR_NOSYSTEM",
+
+		"QUERY_STRING"
+	}
+
+	-- print "!!!"
+	-- html ("!!!")
+	-- print ("<h3>body</h3><table border=1 style='border-collapse: collapse;'><tr><th>Key</th><th>Value</th></tr>")
+	io.stderr:write(arg);
+	for _, attr in pairs(keys) do
+		local l = os.getenv(attr)
+		-- print("<tr><td><pre>" )
+		---print (attr)
+		-- print ("</td><td>")
+		-- print (l)
+		-- print("</pre></td></tr>")
+		io.stderr:write(attr)
+		io.stderr:write(" = " )
+		if l == nil then
+			io.stderr:write("nil");
+		else
+			io.stderr:write(l)
+		end
+		io.stderr:write("\n")
+	end
+	-- print ("</table>")
+end
+
+-- Sets HTTP cookie headers based on post and sets up redirection.
+-- TODO this tries to authenticate on the root page (good), but fails to set
+-- the cookie. I think it gets stuck in the redirect filter (bad).
+-- TODO invalid login also kinda breaks the page... Not found should return the
+-- user to the login page with an error messsage displaed.
+function authenticate_post()
+	local password = users[post["username"]]
+	local redirect = validate_value("redirect", post["redirect"])
+
+	if redirect == nil then
+		not_found()
+		return 0
+	end
+
+	redirect_to(redirect)
+
+	-- Lua hashes strings, so these comparisons are time invariant.
+	if password == nil or password ~= post["password"] then
+		set_cookie("cgitauth", "")
+	else
+		-- One week expiration time
+		local username = secure_value("username", post["username"], os.time() + 604800)
+		set_cookie("cgitauth", username)
+	end
+
+	html("\n")
+	return 0
+end
+
+
+-- Returns 1 if the cookie is valid and 0 if it is not.
+function authenticate_cookie()
+	printenv("Authenticate Cookie\n===================\n");
+
+	-- accepted_users = protected_repos[cgit["repo"]]
+	if public_repos[cgit["repo"]] then
+		-- We return as valid if the repo is not protected.
+		return 1
+	end
+
+
+	local username = validate_value("username", get_cookie(http["cookie"], "cgitauth"))
+	-- if username == nil or not accepted_users[username:lower()] then
+	if username == nil then
+		return 0
+	else
+		return 1
+	end
+end
+
+-- Prints the html for the login form.
+function body()
+	printenv("Body\n====\n");
+
+	html("<p>New login form!</p>");
+	html("<p>But still don't contact me to gain access.</p>");
+	html("<h2>Authentication Required</h2>")
+	html("<form method='post' action='")
+	html_attr(cgit["login"])
+	html("'>")
+	html("<input type='hidden' name='redirect' value='")
+	html_attr(secure_value("redirect", cgit["url"], 0))
+	html("' />")
+	html("<table>")
+	html("<tr><td><label for='username'>Username:</label></td><td><input id='username' name='username' autofocus /></td></tr>")
+	html("<tr><td><label for='password'>Password:</label></td><td><input id='password' name='password' type='password' /></td></tr>")
+	html("<tr><td colspan='2'><input value='Login' type='submit' /></td></tr>")
+	html("</table></form>")
+
+	return 0
+end
+
+
+
+--
+--
+-- Wrapper around filter API, exposing the http table, the cgit table, and the post table to the above functions.
+--
+--
+
+local actions = {}
+actions["authenticate-post"] = authenticate_post
+actions["authenticate-cookie"] = authenticate_cookie
+actions["body"] = body
+
+function filter_open(...)
+	action = actions[select(1, ...)]
+
+	http = {}
+	http["cookie"] = select(2, ...)
+	http["method"] = select(3, ...)
+	http["query"] = select(4, ...)
+	http["referer"] = select(5, ...)
+	http["path"] = select(6, ...)
+	http["host"] = select(7, ...)
+	http["https"] = select(8, ...)
+
+	cgit = {}
+	cgit["repo"] = select(9, ...)
+	cgit["page"] = select(10, ...)
+	cgit["url"] = select(11, ...)
+	cgit["login"] = select(12, ...)
+
+end
+
+function filter_close()
+	return action()
+end
+
+function filter_write(str)
+	post = parse_qs(str)
+end
+
+
+--
+--
+-- Utility functions based on keplerproject/wsapi.
+--
+--
+
+function url_decode(str)
+	if not str then
+		return ""
+	end
+	str = string.gsub(str, "+", " ")
+	str = string.gsub(str, "%%(%x%x)", function(h) return string.char(tonumber(h, 16)) end)
+	str = string.gsub(str, "\r\n", "\n")
+	return str
+end
+
+function url_encode(str)
+	if not str then
+		return ""
+	end
+	str = string.gsub(str, "\n", "\r\n")
+	str = string.gsub(str, "([^%w ])", function(c) return string.format("%%%02X", string.byte(c)) end)
+	str = string.gsub(str, " ", "+")
+	return str
+end
+
+function parse_qs(qs)
+	local tab = {}
+	for key, val in string.gmatch(qs, "([^&=]+)=([^&=]*)&?") do
+		tab[url_decode(key)] = url_decode(val)
+	end
+	return tab
+end
+
+function get_cookie(cookies, name)
+	cookies = string.gsub(";" .. cookies .. ";", "%s*;%s*", ";")
+	return url_decode(string.match(cookies, ";" .. name .. "=(.-);"))
+end
+
+
+--
+--
+-- Cookie construction and validation helpers.
+--
+--
+
+local crypto = require("crypto")
+
+-- Returns value of cookie if cookie is valid. Otherwise returns nil.
+function validate_value(expected_field, cookie)
+	local i = 0
+	local value = ""
+	local field = ""
+	local expiration = 0
+	local salt = ""
+	local hmac = ""
+
+	if cookie == nil or cookie:len() < 3 or cookie:sub(1, 1) == "|" then
+		return nil
+	end
+
+	for component in string.gmatch(cookie, "[^|]+") do
+		if i == 0 then
+			field = component
+		elseif i == 1 then
+			value = component
+		elseif i == 2 then
+			expiration = tonumber(component)
+			if expiration == nil then
+				expiration = -1
+			end
+		elseif i == 3 then
+			salt = component
+		elseif i == 4 then
+			hmac = component
+		else
+			break
+		end
+		i = i + 1
+	end
+
+	if hmac == nil or hmac:len() == 0 then
+		return nil
+	end
+
+	-- Lua hashes strings, so these comparisons are time invariant.
+	if hmac ~= crypto.hmac.digest("sha1", field .. "|" .. value .. "|" .. tostring(expiration) .. "|" .. salt, secret) then
+		return nil
+	end
+
+	if expiration == -1 or (expiration ~= 0 and expiration <= os.time()) then
+		return nil
+	end
+
+	if url_decode(field) ~= expected_field then
+		return nil
+	end
+
+	return url_decode(value)
+end
+
+function secure_value(field, value, expiration)
+	if value == nil or value:len() <= 0 then
+		return ""
+	end
+
+	local authstr = ""
+	local salt = crypto.hex(crypto.rand.bytes(16))
+	value = url_encode(value)
+	field = url_encode(field)
+	authstr = field .. "|" .. value .. "|" .. tostring(expiration) .. "|" .. salt
+	authstr = authstr .. "|" .. crypto.hmac.digest("sha1", authstr, secret)
+	return authstr
+end
+
+function set_cookie(cookie, value)
+	html("Set-Cookie: " .. cookie .. "=" .. value .. "; HttpOnly")
+	if http["https"] == "yes" or http["https"] == "on" or http["https"] == "1" then
+		html("; secure")
+	end
+	html("\n")
+end
+
+function redirect_to(url)
+	html("Status: 302 Redirect\n")
+	html("Cache-Control: no-cache, no-store\n")
+	html("Location: " .. url .. "\n")
+end
+
+function not_found()
+	html("Status: 404 Not Found\n")
+	html("Cache-Control: no-cache, no-store\n\n")
+end