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-rw-r--r--www/git.causal.agency/cgit/filters/simple-authentication.lua314
1 files changed, 0 insertions, 314 deletions
diff --git a/www/git.causal.agency/cgit/filters/simple-authentication.lua b/www/git.causal.agency/cgit/filters/simple-authentication.lua
deleted file mode 100644
index 23d34576..00000000
--- a/www/git.causal.agency/cgit/filters/simple-authentication.lua
+++ /dev/null
@@ -1,314 +0,0 @@
--- This script may be used with the auth-filter. Be sure to configure it as you wish.
---
--- Requirements:
--- 	luaossl
--- 	<http://25thandclement.com/~william/projects/luaossl.html>
--- 	luaposix
--- 	<https://github.com/luaposix/luaposix>
---
-local sysstat = require("posix.sys.stat")
-local unistd = require("posix.unistd")
-local rand = require("openssl.rand")
-local hmac = require("openssl.hmac")
-
---
---
--- Configure these variables for your settings.
---
---
-
--- A list of password protected repositories along with the users who can access them.
-local protected_repos = {
-	glouglou	= { laurent = true, jason = true },
-	qt		= { jason = true, bob = true }
-}
-
--- A list of users and hashes, generated with `mkpasswd -m sha-512 -R 300000`.
-local users = {
-	jason		= "$6$rounds=300000$YYJct3n/o.ruYK$HhpSeuCuW1fJkpvMZOZzVizeLsBKcGA/aF2UPuV5v60JyH2MVSG6P511UMTj2F3H75.IT2HIlnvXzNb60FcZH1",
-	laurent		= "$6$rounds=300000$dP0KNHwYb3JKigT$pN/LG7rWxQ4HniFtx5wKyJXBJUKP7R01zTNZ0qSK/aivw8ywGAOdfYiIQFqFhZFtVGvr11/7an.nesvm8iJUi.",
-	bob		= "$6$rounds=300000$jCLCCt6LUpTz$PI1vvd1yaVYcCzqH8QAJFcJ60b6W/6sjcOsU7mAkNo7IE8FRGW1vkjF8I/T5jt/auv5ODLb1L4S2s.CAyZyUC"
-}
-
--- Set this to a path this script can write to for storing a persistent
--- cookie secret, which should be guarded.
-local secret_filename = "/var/cache/cgit/auth-secret"
-
---
---
--- Authentication functions follow below. Swap these out if you want different authentication semantics.
---
---
-
--- Sets HTTP cookie headers based on post and sets up redirection.
-function authenticate_post()
-	local hash = users[post["username"]]
-	local redirect = validate_value("redirect", post["redirect"])
-
-	if redirect == nil then
-		not_found()
-		return 0
-	end
-
-	redirect_to(redirect)
-
-	if hash == nil or hash ~= unistd.crypt(post["password"], hash) 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()
-	accepted_users = protected_repos[cgit["repo"]]
-	if accepted_users == nil 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
-		return 0
-	else
-		return 1
-	end
-end
-
--- Prints the html for the login form.
-function body()
-	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
-
-function tohex(b)
-	local x = ""
-	for i = 1, #b do
-		x = x .. string.format("%.2x", string.byte(b, i))
-	end
-	return x
-end
-
---
---
--- Cookie construction and validation helpers.
---
---
-
-local secret = nil
-
--- Loads a secret from a file, creates a secret, or returns one from memory.
-function get_secret()
-	if secret ~= nil then
-		return secret
-	end
-	local secret_file = io.open(secret_filename, "r")
-	if secret_file == nil then
-		local old_umask = sysstat.umask(63)
-		local temporary_filename = secret_filename .. ".tmp." .. tohex(rand.bytes(16))
-		local temporary_file = io.open(temporary_filename, "w")
-		if temporary_file == nil then
-			os.exit(177)
-		end
-		temporary_file:write(tohex(rand.bytes(32)))
-		temporary_file:close()
-		unistd.link(temporary_filename, secret_filename) -- Intentionally fails in the case that another process is doing the same.
-		unistd.unlink(temporary_filename)
-		sysstat.umask(old_umask)
-		secret_file = io.open(secret_filename, "r")
-	end
-	if secret_file == nil then
-		os.exit(177)
-	end
-	secret = secret_file:read()
-	secret_file:close()
-	if secret:len() ~= 64 then
-		os.exit(177)
-	end
-	return secret
-end
-
--- 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 chmac = ""
-
-	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
-			chmac = component
-		else
-			break
-		end
-		i = i + 1
-	end
-
-	if chmac == nil or chmac:len() == 0 then
-		return nil
-	end
-
-	-- Lua hashes strings, so these comparisons are time invariant.
-	if chmac ~= tohex(hmac.new(get_secret(), "sha256"):final(field .. "|" .. value .. "|" .. tostring(expiration) .. "|" .. salt)) 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 = tohex(rand.bytes(16))
-	value = url_encode(value)
-	field = url_encode(field)
-	authstr = field .. "|" .. value .. "|" .. tostring(expiration) .. "|" .. salt
-	authstr = authstr .. "|" .. tohex(hmac.new(get_secret(), "sha256"):final(authstr))
-	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