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NDG Security: Distributed Governance, Distributed Access Control, Distributed Data. Bryan Lawrence (on behalf of a big team). +. +. ]=. +[. +. +. BADC, BODC, CCLRC, PML and SOC. NCAR. Complexity + Volume + Remote Access = Grid Challenge. British Atmospheric Data Centre.
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NDG Security: Distributed Governance, Distributed Access Control, Distributed Data. Bryan Lawrence (on behalf of a big team) + + ]= +[ + + BADC, BODC, CCLRC, PML and SOC
NCAR Complexity + Volume + Remote Access = Grid Challenge British Atmospheric Data Centre http://ndg.nerc.ac.uk British Oceanographic Data Centre
No one would change their data storage systems! Need to support a wide range of “metadata-maturity”! No NDG-wide user management system possible. It is illegal to share user information without each and every user agreeing … implies no way of having one virtual organisation with common user management! With a large enough group it is impossible to agree on common roles that could be associated with access control. … but we want single-sign on … and trust relationships between data providers … NDG Assumptions
Clean separation between concepts: Authentication Identity - Who you are Users are identified between data providers and services by means of Proxy Certificates Proxy Certificates issued by MyProxy services Users are identified between sessions at the same browser by means of a cookie which points to the location of a proxy certificate. Authorisation For a user: what you can do e.g. what data they can access For a data provider: how you determine what a user can and can’t do NDG Attribute Certificates determine access Attribute Certificates issued by AttributeAuthorities. Authentication and Authorisation
Controlling Access to Data • NDG Attribute Certificate • Issued to a user by an ATTRIBUTE-AUTHORITY • Contain roles – these determine what the user is authorised to do • An attribute authority determines on behalf of a data provider what roles a user has, from the list of roles known to that data provider • e.g. badc has the coapec role which allows access to the coapec data set. If a badc user has a badc issued Attribute Certificate containing coapec then badc will grant access. • XML based • Issued by the Attribute Authorities on receipt of a valid user Proxy Certificate • Digitally signed by the Attribute Authority issuer • Contain the user’s identity expressed as a Distinguished Name as derived from the user’s Proxy Certificate • Has a timebound validity
All data providers deploy, or have access to, a myproxy database capable of delivering proxy certificates on request. All data providers deploy or have access to a Session Manager instance. No requirement for the myproxy to visible outside a firewall, access can be mediated by a Session Manager. All data providers secure resources by coupling resources to roles. There is no assumption that data providers share the same role names or role definitions. All data providers deploy, or have access to, Attribute Authorities that grant NDG Attribute Certificates to users based on their “rights”. Key Concepts thus far
<?xml version="1.0" encoding="utf-8"?> <AAmap> <thisHost name="BADC"> <wsdl>badcAttAuthorityURI</wsdl> <loginURI>badcLoginPageURI</loginURI> </thisHost> <trusted name="BODC"> <wsdl>bodcAttAuthorityURI</wsdl> <loginURI>bodcLoginPageURI</loginURI> <role remote="aBODCrole" local="aLocalRole"/> </trusted> <trusted name="escience"> <wsdl>eScienceAttAuthorityURI</wsdl> <role remote="anEScienceRole" local="anotherLocalRole"/> </trusted> </AAmap> HANDLES AUTHORISATION HANDLES AUTHENTICATION LIST OF REMOTE ADDRESSES FOR GETTING AUTHORISATION CREDENTIALS AUTHORISATION Example MapConfig TRUST Trust between data providers is established by making BILATERAL agreements on role mapping!
Authenticate when trying to access a secured resource (which has role, AAwsdl). Pole AAwsdl for trusted host list (including self) Choose a login Application should redirect to a loginURL Login … Login Service establishes an NDG Session Manager, and populates it with proxy certificate/ LoginURL sets a cookie and redirects back to originator with cookie details in URL (if not local) (All redirections done with https) Originator sets cookie with session manager details Originator establishes local session manager session that knows about remote session manager via cookie contents. Browser User Authentication
AA Client Application smClient User Authorisation • UserSession • CredWallet SessionManager WS sessionID and smWSDL reqRole AAwsdl ProxyCert, reqAttCert AttCert (Installable Library) Returned Proxy Cert. is kept in CredWallet of user’s UserSession instance Calls FIREWALL Exploits reqAuthorisaton method Local smClient talks to local SessionManager which may or may not talk to remote SessionManagers. Credential Wallet is populated with attribute certificates as needed.
What’s needed to represent ID? [User DataBase of some sort] [PKI/Proxy Certificates] [MyProxy Server] [Session Manager] What’s needed to grant access rights to a user? [Attribute Authority] [Session Manager] Some “database” binding resources to roles and AA How to Deploy a system [Indicate that a minimally configured data provider can use remote resources to provide these services]
Python Browser Application class YourClass: ''' Dummy class encapsulating key ndg security concepts from a browser application developers perspective ''' def __init__(self,stuff): ... self.cookie=... #set cookie self.config=... #read from config file, includes local smWSDL …. self.makeGateway() ... def makeGateway(self,cookie=None): ''' Make connection to NDG security and load what is necessary for an NDG cookie to be written ''' # - the requestURL so that a redirect can come back, and to pass # any URL components which have come back from one ... # - your local smWSDL address, and your cookie ... self.ndgGate=securityGateway(self.requestURL,self.cookie,self.config) def goforit(self): ''' your actions ... trying to access a URI for which you may have constraints''' ... if constraints.exist: result=self.ndgGate.check((role,AAwsdl)) if result=='AccessGranted': access=1 else: access=0
NDG Started Phase 2 in 2006 with Alpha Stage milestone this week: Target secure data resource with NDG security Done (both for A and B metadata) Engineered NDG security into BBFTP … Working prototype implemented in Python: Deployed at partner sites: British Oceanographic Data Centre, National Oceanography Centre Southampton, Plymouth Marine Lab and Centre for Ecology and Hydrology Supports single sign on Uses XML Signature and XML encryption but not WS-Security compliant (yet) Uses WSDL Open Source NDG Security Current Status
WS interfaces need to be adapted to be compliant to WS-Security Produce Java implementation for DEWS Adapt ZSI Python WS libraries Possibly use LBL libraries – pyGridWare Latest status info: NDG Project Management Trac site (http://proj.badc.rl.ac.uk/ndg/) Security Next Steps
DEWS Delivering Environmental Web Services • Department of Trade and Industry funding … • health stream (new WFS) • Marine stream (new WCS based on GADS) • NDG Security • Prototype for commercial activity
CSML NCML+CF DIF -> ISO19115 Architecture: NDG Metadata Taxonomy MOLES THREDDS (… NMM, SENSORML etc) CLADDIER … not one schema, not one solution!
Vocab Services Users NDG GUI Interface(s) Data Providers NDG Core Services Architecture: Deployment
Vocab Services Users NDG GUI Interface(s) NDG Core Services Architecture: Deployment
Vocab Services Users NDG GUI Interface(s) Architecture: Deployment
Vocab Services Users Architecture: Deployment
Core linking concept is the deployment MOLES: implementation of a Data Production Tool at an Observation Station on behalf of an Activity that produces a Data Entity Activity DataProductionTool ObservationStation Links the metadata records into a structure that can be turned into a navigable structure Deployment Each of the main metadata objects has security data attached to it. This means that this can be applied to queries on the metadata Data Entity
NDG “Pseudo-Demo” EXPLOITING DISCOVERY WEB SERVICE (running interface on my laptop last night)
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MOLES Navigation Actually, this is where we plan to use NMM
Offering up trusted host list … NDG Authentication
NDG2 runs until September 2007: NDG-Alpha (June 2006) Not all components in place (particularly delivery broker) Not many (maybe only DX) products will be deployable by non-NDG participants (too much hard work installing things that haven’t been optimised for installation) Discovery portal will be (is now) usable, linking to NCAR data etc, but isn’t very user friendly (options not obvious etc). NDG-Beta (Feb 2007) Most components should work, but deployment of software may still be difficult by non-participants NDG-Prod (Jun 2007) Should be deployable and far more user friendly (spending from Feb-June working on deployment and friendliness, no new functionality) Last few months working on sustainability etc NDG Timeline http://proj.badc.rl.ac.uk/trac/roadmap