120 lines
4.0 KiB
Lua
120 lines
4.0 KiB
Lua
-- The MIT License (MIT)
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--
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-- Copyright (c) 2018 Tim Düsterhus
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--
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-- Permission is hereby granted, free of charge, to any person obtaining a copy
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-- of this software and associated documentation files (the "Software"), to deal
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-- in the Software without restriction, including without limitation the rights
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-- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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-- copies of the Software, and to permit persons to whom the Software is
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-- furnished to do so, subject to the following conditions:
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--
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-- The above copyright notice and this permission notice shall be included in all
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-- copies or substantial portions of the Software.
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--
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-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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-- SOFTWARE.
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local http = require("haproxy-lua-http")
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function set_var_pre_2_2(txn, var, value)
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return txn:set_var(var, value)
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end
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function set_var_post_2_2(txn, var, value)
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return txn:set_var(var, value, true)
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end
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set_var = function(txn, var, value)
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local success = pcall(set_var_post_2_2, txn, var, value)
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if success then
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set_var = set_var_post_2_2
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else
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set_var = set_var_pre_2_2
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end
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return set_var(txn, var, value)
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end
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function sanitize_header_for_variable(header)
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return header:gsub("[^a-zA-Z0-9]", "_")
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end
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core.register_action("auth-request", { "http-req" }, function(txn, be, path)
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set_var(txn, "txn.auth_response_successful", false)
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-- Check whether the given backend exists.
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if core.backends[be] == nil then
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txn:Alert("Unknown auth-request backend '" .. be .. "'")
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set_var(txn, "txn.auth_response_code", 500)
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return
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end
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-- Check whether the given backend has servers that
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-- are not `DOWN`.
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local addr = nil
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for name, server in pairs(core.backends[be].servers) do
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local status = server:get_stats()['status']
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if status == "no check" or status:find("UP") == 1 then
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addr = server:get_addr()
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break
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end
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end
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if addr == nil then
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txn:Warning("No servers available for auth-request backend: '" .. be .. "'")
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set_var(txn, "txn.auth_response_code", 500)
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return
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end
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-- Transform table of request headers from haproxy's to
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-- socket.http's format.
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local headers = {}
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for header, values in pairs(txn.http:req_get_headers()) do
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if header ~= 'content-length' then
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for i, v in pairs(values) do
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if headers[header] == nil then
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headers[header] = v
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else
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headers[header] = headers[header] .. ", " .. v
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end
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end
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end
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end
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-- Make request to backend.
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local response, err = http.head {
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url = "http://" .. addr .. path,
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headers = headers,
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}
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-- Check whether we received a valid HTTP response.
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if response == nil then
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txn:Warning("Failure in auth-request backend '" .. be .. "': " .. err)
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set_var(txn, "txn.auth_response_code", 500)
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return
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end
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set_var(txn, "txn.auth_response_code", response.status_code)
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for header, value in response:get_headers(true) do
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set_var(txn, "req.auth_response_header." .. sanitize_header_for_variable(header), value)
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end
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-- 2xx: Allow request.
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if 200 <= response.status_code and response.status_code < 300 then
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set_var(txn, "txn.auth_response_successful", true)
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-- Don't allow other codes.
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-- Codes with Location: Passthrough location at redirect.
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elseif response.status_code == 301 or response.status_code == 302 or response.status_code == 303 or response.status_code == 307 or response.status_code == 308 then
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set_var(txn, "txn.auth_response_location", response:get_header("location", "last"))
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-- 401 / 403: Do nothing, everything else: log.
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elseif response.status_code ~= 401 and response.status_code ~= 403 then
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txn:Warning("Invalid status code in auth-request backend '" .. be .. "': " .. response.status_code)
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end
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end, 2)
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