pep/src/pep.js

427 lines
15 KiB
JavaScript

export default { enforce };
import defaultExport from './config.js';
function log(c, s){
c.request.error(s)
}
var _debug = defaultExport["debug"]
function debug(c, s){
if(_debug === true){
log(c, s)
}
}
function enforce(r) {
var context = {
request: r ,
config : defaultExport["config"],
backend : (defaultExport.backend ? defaultExport.backend : "/_backend")
}
log(context, "Inside NJS enforce for " + r.method + " @ " + r.headersIn.host + r.uri)
context = computeProtection(context)
wkf.run(wkf.build(context), context)
}
// ######## WORKFLOW FUNCTIONS ###############
var wkf = {
build : (context)=>{
var actions = [
"export_pep_credentials",
"parse_authentication",
"check_authentication",
"export_authn_token",
// "pip",
"pdp",
// "export_backend_headers",
// "pass"
"start_accounting",
"pass_and_wait",
"close_accounting",
"send_accounting",
"respond_to_client"
]
/*var actions = [
"export_pep_credentials",
"parse_authentication",
"check_authentication",
"export_authn_token",
"pip",
"pdp",
"export_backend_headers",
"start_accounting",
"pass_and_wait",
"close_accounting",
"respond_to_client"
]*/
return actions
},
run : (actions, context) => {
context.request.error("Starting workflow with " + njs.dump(actions))
var w = actions.reduce(
(acc, f) => { return acc.then(typeof(f) === "function" ? f : wkf[f]) },
Promise.resolve().then(()=>context)
)
w.catch(e => { context.request.error(njs.dump(e)); context.request.return(401)} )
},
export_pep_credentials : exportPepCredentials,
export_authn_token : exportAuthToken,
export_backend_headers : exportBackendHeaders,
parse_authentication : parseAuthentication,
check_authentication : checkAuthentication,
verify_token : verifyToken,
request_token : requestToken,
pip : pipExecutor,
pdp : pdpExecutor,
pass : pass,
pass_and_wait : pass_and_wait,
respond_to_client : respondToClient,
start_accounting : buildAccountingRecord,
close_accounting : closeAccountingRecord,
send_accounting : sendAccountingRecord
}
function getTokenField(context, f){
return context.authn.verified_token[f]
}
function exportVariable(context, name, value){
context.request.variables[name] = value
return context
}
function exportBackendHeaders(context){
return context
}
function exportPepCredentials(context){
if(process.env["pep_credentials"] || process.env["PEP_CREDENTIALS"]){
return exportVariable(context, "pep_credentials", "Basic " + process.env["PEP_CREDENTIALS"])
}else if(context.config["pep_credentials"]){
return exportVariable(context, "pep_credentials", "Basic " + context.config["pep_credentials"])
}else{
throw new Error("Need PEP credentials")
}
}
function exportAuthToken(context){
return exportVariable(context, "auth_token", context.authn.token)
}
function checkAuthentication(context){
return context.authn.type === "bearer" ? wkf.verify_token(context) : wkf.request_token(context)
}
function parseAuthentication(context){
context.request.log("Inside parseAuthentication")
var incomingauth = context.request.headersIn["Authorization"]
if(!incomingauth) throw new Error("Authentication required");
var arr = incomingauth.trim().replace(/\s\s+/g, " ").split(" ")
if(arr.length != 2) throw new Error("Unknown authentication scheme");
var type = arr[0].toLowerCase()
if(type === "basic" && context.authz.host && (context.authz.host["allow-basic-auth"] || context.authz.host["allow_basic_auth"])) {
var unamepass = Buffer.from(arr[1], 'base64').toString().split(":")
if(unamepass.length != 2) return null;
context.authn = { type : type, raw : arr[1], user : unamepass[0], password : unamepass[1]}
return context
}else if(type === "bearer"){
context.authn = { type : type, raw : arr[1], token : arr[1]}
return context
}
throw new Error("Unknown authentication scheme");
}
function verifyToken(context){
log(context, "Inside verifyToken")
debug(context, "Token is " + context.authn.token)
var options = {
"body" : "token=" + context.authn.token + "&token_type_hint=access_token"
}
return context.request.subrequest("/jwt_verify_request", options)
.then(reply=>{
if (reply.status === 200) {
var response = JSON.parse(reply.responseText);
if (response.active === true) {
return response
} else {
throw new Error("Unauthorized: " + reply.responseText)
}
} else {
throw new Error("Unauthorized: " + reply.responseText)
}
}).then(verified_token => {
context.authn.verified_token =
JSON.parse(Buffer.from(context.authn.token.split('.')[1], 'base64url').toString())
return context
})
}
function requestToken(context){
log(context, "Inside requestToken")
var options = {
"body" : "grant_type=client_credentials&client_id="+context.authn.user+"&client_secret="+context.authn.password
}
return context.request.subrequest("/jwt_request", options)
.then(reply=>{
if (reply.status === 200) {
var response = JSON.parse(reply.responseText);
context.authn.token = response.access_token
context.authn.verified_token =
JSON.parse(Buffer.from(context.authn.token.split('.')[1], 'base64url').toString())
return context
} else if (reply.status === 400 || reply.status === 401){
var options = {
"body" : "grant_type=password&username="+context.authn.user+"&password="+context.authn.password
}
return context.request.subrequest("/jwt_request", options)
.then( reply=>{
if (reply.status === 200) {
var response = JSON.parse(reply.responseText);
context.authn.token = response.access_token
context.authn.verified_token =
JSON.parse(Buffer.from(context.authn.token.split('.')[1], 'base64url').toString())
return context
} else{
throw new Error("Unauthorized " + reply.status)
}
})
} else {
throw new Error("Unauthorized " + reply.status)
}
})
}
function pipExecutor(context){
log(context, "Inside extra claims PIP")
context.authz.pip.forEach(extra =>{
//call extra claim pip function
try{
var operator = extra.operator
var result = wkf[operator](context, extra.args)
//ensure array and add to extra_claims
if(!(result instanceof Array)) result = [result]
if(!context.extra_claims) context.extra_claims = {};
context.extra_claims[extra.claim] = result
} catch (error){
log(context, "Skipping invalid extra claim " + njs.dump(error))
}
})
log(context, "Extra claims are " + njs.dump(context.extra_claims))
return context
}
function pdpExecutor(context){
log(context, "Inside PDP")
return context.authz.pdp(context)
}
function umaCall(context){
log(context, "Inside UMA call")
var options = { "body" : computePermissionRequestBody(context) };
return context.request.subrequest("/permission_request", options)
.then(reply =>{
if(reply.status === 200){
debug(context, "UMA call reply is " + reply.status)
return context
}else{
throw new Error("Response for authorization request is not ok " + reply.status + " " + njs.dump(reply.responseText))
}
})
}
// Call backend and return reply to client directly
async function pass(context){
log(context, "Inside pass and wait");
const r = context.request
const reply = await r.subrequest(context.backend, { method : r.method, args : r.variables.args, headers : r.headersIn})
debug(context, "[BACKEND] response status: " + reply.status)
context.backendresponse = reply
return respondToClient(context)
}
// Pass to backend but instead of returning to client wait for the reply. Thi intercepts the possibility of performing extra action like closing and sending accounting record.
async function pass_and_wait(context){
log(context, "Inside pass and wait");
const r = context.request
const reply = await r.subrequest(context.backend, { method : r.method, args : r.variables.args, headers : r.headersIn})
debug(context, "[BACKEND] response status: " + reply.status)
context.backendresponse = reply
return context
}
// Definetely return backend response
function respondToClient(context){
log(context, "Inside respond to client" + njs.dump(context.backendresponse));
for(let k in context.backendresponse.headersOut){
context.request.headersOut[k] = context.backendresponse.headersOut[k]
}
context.request.return(context.backendresponse.status, context.backendresponse.responseText)
return context
}
// ######## AUTHORIZATION PART ###############
function computePermissionRequestBody(context){
if(!context.authz.host || !context.authz.path ){
throw new Error("Enforcemnt mode is always enforcing. Host or path not found...")
}
var audience = computeAudience(context)
var grant = "grant_type=urn:ietf:params:oauth:grant-type:uma-ticket"
var mode = "response_mode=decision"
var permissions = computePermissions(context)
var extra = ""
if(context.extra_claims){
extra =
"claim_token_format=urn:ietf:params:oauth:token-type:jwt&claim_token=" +
JSON.stringify(context.extra_claims).toString("base64url")
}
var body = audience + "&" + grant + "&" + permissions + "&" + mode + "&" + extra
context.request.error("Computed permission request body is " + body)
return body
}
function computeAudience(context){
var aud = context.request.headersIn.host
if(context.authz.host){
aud = context.authz.host.audience||context.authz.host.host
}
return "audience=" + aud
}
function computePermissions(context){
var resource = context.request.uri
if(context.authz.path){
resource = context.authz.path.name||context.authz.path.path
}
var scopes = []
if(context.authz.method && context.authz.method.scopes){
scopes = context.authz.method.scopes
}
if(scopes.length > 0){
return scopes.map(s=>"permission=" + resource + "#" + s).join("&")
}
return "permission=" + resource
}
function getPath(hostconfig, incomingpath, incomingmethod){
var paths = hostconfig.paths || []
var matchingpaths = paths
.filter(p => {return incomingpath.match(p.path) != null})
.reduce((acc, p) => {
if (!p.methods || p.methods.length === 0) acc.weak.push({ path: p});
else{
var matchingmethods = p.methods.filter(m=>m.method.toUpperCase() === incomingmethod)
if(matchingmethods.length > 0) acc.strong.push({ method : matchingmethods[0], path: p});
}
return acc;
}, { strong: [], weak: []})
return matchingpaths.strong.concat(matchingpaths.weak)[0]
}
function getHost(config, host){
var matching = config.hosts.filter(h=>{
//compare for both string and array of strings
return ((h.host.filter && h.host.indexOf(host) !== -1) || h.host === host)
})
return matching.length > 0 ? matching[0] : null
}
function computeProtection(context){
debug(context, "Getting by host " + context.request.headersIn.host)
context.authz = {}
context.authz.host = getHost(context.config, context.request.headersIn.host)
if(context.authz.host !== null){
log(context, "Host found:" + context.authz.host)
context.authz.pip = context.authz.host.pip ? context.authz.host.pip : [];
context.authz.pdp = context.authz.host.pdp ? context.authz.host.pdp : umaCall;
var pathandmethod = getPath(context.authz.host, context.request.uri, context.request.method);
if(pathandmethod){
context.authz.path = pathandmethod.path;
context.authz.pip = context.authz.path.pip ? context.authz.pip.concat(context.authz.path.pip) : context.authz.pip;
context.authz.pdp = context.authz.path.pdp ? context.authz.path.pdp : context.authz.pdp;
context.authz.method = pathandmethod.method;
if(context.authz.method){
context.authz.pip = context.authz.method.pip ? context.authz.pip.concat(context.authz.method.pip) : context.authz.pip;
context.authz.pdp = context.authz.method.pdp ? context.authz.method.pdp : context.authz.pdp;
}
}
}
debug(context, "Leaving protection computation: ")
return context
}
// ####### ACCOUNTING PART #####################
function buildAccountingRecord(context){
log(context, "Inside build accounting record");
const t = (new Date()).getTime()
context.record = {
"recordType": "ServiceUsageRecord",
"operationCount": 1,
"creationTime": t,
"callerHost": context.request.headersIn["x-forwarded-for"],
"serviceClass": "Application",
"callerQualifier": "TOKEN",
"consumerId": getTokenField(context, "preferred_username"),
"aggregated": true,
"serviceName": defaultExport["accounting"]["service_name"],
"duration": 0,
"maxInvocationTime": 0,
"scope": defaultExport["accounting"]["scope"],
"host": defaultExport["accounting"]["host"],
"startTime": t,
"id": uuid(),
"calledMethod": context.request.method + " " + context.request.uri,
"endTime": 0,
"minInvocationTime": 0,
"operationResult": null
}
debug(context, "Record is " + JSON.stringify(context.record))
return context
}
function closeAccountingRecord(context, success){
log(context, "Inside close accounting");
const t = (new Date()).getTime()
context.record.duration = t - context.record.startTime
context.record.endTime = t
context.record.minInvocationTime = context.record.duration
context.record.operationResult = success ? "SUCCESS" : "FAILED";
debug(context, "Record is " + JSON.stringify(context.record))
return context
}
async function sendAccountingRecord(context){
log(context, "Inside send accounting");
const detached = !_debug;
const subreq_params = { detached : detached, body : JSON.stringify([context.record]) };
if (_debug) {
// debug(context, JSON.stringify(subreq_params));
const acc_request = await context.request.subrequest("/accounting", subreq_params);
debug(context, "[ACCOUNTING] response status: " + JSON.stringify(acc_request));
} else {
context.request.subrequest("/accounting", subreq_params);
}
// const acc_request = await context.request.subrequest("/accounting", { detached : false, body : JSON.stringify([context.record]) })
// debug(context, "[ACCOUNTING] response status: " + acc_request.status)
// debug(context, "[ACCOUNTING] " + njs.dump(acc_request));
return context
}
function uuid() {
return 'xxxxxxxx-xxxx-4xxx-8xxx-xxxxxxxxxxxx'.replace(/[x]/g, function (c) {
const r = Math.random() * 16 | 0, v = c == 'x' ? r : (r & 0x3 | 0x8);
return v.toString(16);
});
}