Challenges in Deploying Low-Latency Anonymity (DRAFT)
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Arxiv:1907.07120V1 [Cs.CY] 16 Jul 2019 1 Introduction That China Hindered Access to I2P by Poisoning DNS Resolu- Tions of the I2P Homepage and Three Reseed Servers
Measuring I2P Censorship at a Global Scale Nguyen Phong Hoang Sadie Doreen Michalis Polychronakis Stony Brook University The Invisible Internet Project Stony Brook University Abstract required flexibility for conducting fine-grained measurements on demand. We demonstrate these benefits by conducting an The prevalence of Internet censorship has prompted the in-depth investigation of the extent to which the I2P (invis- creation of several measurement platforms for monitoring ible Internet project) anonymity network is blocked across filtering activities. An important challenge faced by these different countries. platforms revolves around the trade-off between depth of mea- Due to the prevalence of Internet censorship and online surement and breadth of coverage. In this paper, we present surveillance in recent years [7, 34, 62], many pro-privacy and an opportunistic censorship measurement infrastructure built censorship circumvention tools, such as proxy servers, virtual on top of a network of distributed VPN servers run by vol- private networks (VPN), and anonymity networks have been unteers, which we used to measure the extent to which the developed. Among these tools, Tor [23] (based on onion rout- I2P anonymity network is blocked around the world. This ing [39,71]) and I2P [85] (based on garlic routing [24,25,33]) infrastructure provides us with not only numerous and ge- are widely used by privacy-conscious and censored users, as ographically diverse vantage points, but also the ability to they provide a higher level of privacy and anonymity [42]. conduct in-depth measurements across all levels of the net- In response, censors often hinder access to these services work stack. -
Hacking the Web
Hacking the Web (C) 2009-2020 Arun Viswanathan Ellis Horowitz Marco Papa 1 Table of Contents } General Introduction } Authentication Attacks } Client-Side Attacks } Injection Attacks } Recent Attacks } Privacy Tools 2 (C) 2009-2020 Arun Viswanathan Ellis Horowitz Marco Papa Why secure the Web? } The Web has evolved into an ubiquitous entity providing a rich and common platform for connecting people and doing business. } BUT, the Web also offers a cheap, effective, convenient and anonymous platform for crime. } To get an idea, the Web has been used for the following types of criminal activities (source: The Web Hacking Incidents Database (WHID) http://projects.webappsec.org/w/page/13246995/Web-Hacking-Incident-Database) } Chaos (Attack on Russian nuclear power websites amid accident rumors (5Jan09) } Deceit (SAMY XSS Worm – Nov 2005) } Extortion (David Aireys domain hijacked due to a CSRF (cross site request forgery) flaw in Gmail – 30Dec2007) } Identity Theft (XSS on Yahoo! Hot jobs – Oct 2008) } Information Warfare (Israeli Gaza War - Jan 2009 / Balkan Wars – Apr 2008 ) } Monetary Loss (eBay fraud using XSS) } Physical Pain (Hackers post on epilepsy forum causes migraines and seizures – May 2008) } Political Defacements (Hacker changes news release on Sheriffs website – Jul 2008) (Obama, Oreilly and Britneys Twitter accounts hacked and malicious comments posted – Jan 09) } Chinese Gaming sites hacked (Dec. 2011) 3 Copyright(C) 2009 (c) -20092020- 2019Arun Arun Viswanathan Viswanathan Ellis HorowitzEllis Horowitz Marco Marco Papa Papa -
Tor and Circumvention: Lessons Learned
Tor and circumvention: Lessons learned Nick Mathewson The Tor Project https://torproject.org/ 1 What is Tor? Online anonymity 1) open source software, 2) network, 3) protocol Community of researchers, developers, users, and relay operators Funding from US DoD, Electronic Frontier Foundation, Voice of America, Google, NLnet, Human Rights Watch, NSF, US State Dept, SIDA, ... 2 The Tor Project, Inc. 501(c)(3) non-profit organization dedicated to the research and development of tools for online anonymity and privacy Not secretly evil. 3 Estimated ~250,000? daily Tor users 4 Anonymity in what sense? “Attacker can’t learn who is talking to whom.” Bob Alice Alice Anonymity network Bob Alice Bob 5 Threat model: what can the attacker do? Alice Anonymity network Bob watch Alice! watch (or be!) Bob! Control part of the network! 6 Anonymity isn't cryptography: Cryptography just protects contents. “Hi, Bob!” “Hi, Bob!” Alice <gibberish> attacker Bob 7 Anonymity isn't just wishful thinking... “You can't prove it was me!” “Promise you won't look!” “Promise you won't remember!” “Promise you won't tell!” “I didn't write my name on it!” “Isn't the Internet already anonymous?” 8 Anonymity serves different interests for different user groups. Anonymity “It's privacy!” Private citizens 9 Anonymity serves different interests for different user groups. Anonymity Businesses “It's network security!” “It's privacy!” Private citizens 10 Anonymity serves different interests for different user groups. “It's traffic-analysis resistance!” Governments Anonymity Businesses “It's network security!” “It's privacy!” Private citizens 11 Anonymity serves different interests for different user groups. -
Threat Modeling and Circumvention of Internet Censorship by David Fifield
Threat modeling and circumvention of Internet censorship By David Fifield A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Computer Science in the Graduate Division of the University of California, Berkeley Committee in charge: Professor J.D. Tygar, Chair Professor Deirdre Mulligan Professor Vern Paxson Fall 2017 1 Abstract Threat modeling and circumvention of Internet censorship by David Fifield Doctor of Philosophy in Computer Science University of California, Berkeley Professor J.D. Tygar, Chair Research on Internet censorship is hampered by poor models of censor behavior. Censor models guide the development of circumvention systems, so it is important to get them right. A censor model should be understood not just as a set of capabilities|such as the ability to monitor network traffic—but as a set of priorities constrained by resource limitations. My research addresses the twin themes of modeling and circumvention. With a grounding in empirical research, I build up an abstract model of the circumvention problem and examine how to adapt it to concrete censorship challenges. I describe the results of experiments on censors that probe their strengths and weaknesses; specifically, on the subject of active probing to discover proxy servers, and on delays in their reaction to changes in circumvention. I present two circumvention designs: domain fronting, which derives its resistance to blocking from the censor's reluctance to block other useful services; and Snowflake, based on quickly changing peer-to-peer proxy servers. I hope to change the perception that the circumvention problem is a cat-and-mouse game that affords only incremental and temporary advancements. -
Tor: the Second-Generation Onion Router (2014 DRAFT V1)
Tor: The Second-Generation Onion Router (2014 DRAFT v1) Roger Dingledine Nick Mathewson Steven Murdoch The Free Haven Project The Free Haven Project Computer Laboratory [email protected] [email protected] University of Cambridge [email protected] Paul Syverson Naval Research Lab [email protected] Abstract Perfect forward secrecy: In the original Onion Routing We present Tor, a circuit-based low-latency anonymous com- design, a single hostile node could record traffic and later munication service. This Onion Routing system addresses compromise successive nodes in the circuit and force them limitations in the earlier design by adding perfect forward se- to decrypt it. Rather than using a single multiply encrypted crecy, congestion control, directory servers, integrity check- data structure (an onion) to lay each circuit, Tor now uses an ing, configurable exit policies, anticensorship features, guard incremental or telescoping path-building design, where the nodes, application- and user-selectable stream isolation, and a initiator negotiates session keys with each successive hop in practical design for location-hidden services via rendezvous the circuit. Once these keys are deleted, subsequently com- points. Tor is deployed on the real-world Internet, requires promised nodes cannot decrypt old traffic. As a side benefit, no special privileges or kernel modifications, requires little onion replay detection is no longer necessary, and the process synchronization or coordination between nodes, and provides of building circuits is more reliable, since the initiator knows a reasonable tradeoff between anonymity, usability, and ef- when a hop fails and can then try extending to a new node. -
Piracy Versus Privacy: an Analysis of Values Encoded in the Piratebrowser
International Journal of Communication 9(2015), 818–838 1932–8036/20150005 Piracy Versus Privacy: An Analysis of Values Encoded in the PirateBrowser BALÁZS BODÓ University of Amsterdam, Institute for Information Law The Netherlands The PirateBrowser is a Web browser that uses Tor privacy-enhancing technology to circumvent nationally implemented Internet filters blocking access to The Pirate Bay. This article analyzes the possible consequences of a mass influx of copyright pirates into the privacy domain. The article addresses the effects of the uptake of strong privacy technologies by pirates on copyright enforcement and on free speech and privacy technology domains. Also discussed are the norms and values reflected in the specific design choices taken by the developers of the PirateBrowser. Keywords: piracy, privacy, Tor, privacy-enhancing technologies, policy Introduction Tor (The Onion Router), “endorsed by Egyptian activists, WikiLeaks, NSA, GCHQ, Chelsea Manning, Snowden” (Dingledine & Appelbaum, 2013), is a volunteer network of computers that relays Web traffic through itself to provide anonymous, unobserved, and uncensored access to the Internet. It has about 4,000 relays and about 1,000 exit nodes. Tor users connect to the network, and their Web traffic is channeled through the internal relays to reach its final destination through one of the exit nodes. This arrangement makes the identification and surveillance of Tor users difficult. Anonymity is promised by the difficulty of tracing the Web traffic that appears on the exit node back to the individual who initiated the traffic, as long as there is a sufficient number of internal hops in between. Protection from surveillance is granted by the fact that each link in the communication chain is encrypted. -
Jacob Appelbaum, Wikileaks Activist and Tor Project Leader, Travels to Beijing to Work with Artist/Activist Ai We
Breaking News: Jacob Appelbaum, Wikileaks activist and Tor Project leader, travels to Beijing to work with artist/activist Ai Weiwei for Rhizome's Seven on Seven conference at the New Museum. Laura Poitras documents the pair in her first film since Citizenfour, premiering excerpts at the event on May 2. On Saturday, April 19, Jacob Appelbaum—notable Wikileaks and Tor Project activist—traveled to Beijing for five days to take part in a collaboration with dissident artist Ai Weiwei, at the invitation of art- meets-tech organization Rhizome, on the occasion of the seventh Seven on Seven conference at the New Museum. Director Laura Poitras, whose portrait of Edward Snowden won the 2015 Academy Award for Documentary Feature, filmed the duo's work. Seven on Seven is an annual signature conference with a unique format that pairs artists and technologists together to make something new in 24 hours. The pair worked to create an artwork that underscores their mutual concerns with privacy, surveillance, and their state-restricted movement. Excerpts of the short film documenting this collaboration—Poitras' first since Citizenfour—will be premiered at the event, held at New Museum in New York on May 2, and the final film will be released online later in May. The Appelbaum/Ai collaboration was organized by Heather Corcoran, Executive Director of Rhizome, who said: “It was important to bring together these two courageous people who are disseminating their messages using art and technology, respectively, and facing similar levels of scrutiny and hardship as a result. It represents the best that Rhizome achieves with Seven on Seven, which brings the worlds of technology and art into closer proximity, to share strategies for thinking critically about digital culture and communicating those ideas. -
Tor: a Quick Overview
Tor: a quick overview Roger Dingledine The Tor Project https://torproject.org/ 1 What is Tor? Online anonymity 1) open source software, 2) network, 3) protocol Community of researchers, developers, users, and relay operators Funding from US DoD, Electronic Frontier Foundation, Voice of America, Google, NLnet, Human Rights Watch, NSF, US State Dept, SIDA, Knight Foundation, ... 2 The Tor Project, Inc. 501(c)(3) non-profit organization dedicated to the research and development of tools for online anonymity and privacy 3 Estimated 600,000? daily Tor users 4 Threat model: what can the attacker do? Alice Anonymity network Bob watch Alice! watch (or be!) Bob! Control part of the network! 5 Anonymity isn't encryption: Encryption just protects contents. “Hi, Bob!” “Hi, Bob!” Alice <gibberish> attacker Bob 6 Anonymity isn't just wishful thinking... “You can't prove it was me!” “Promise you won't look!” “Promise you won't remember!” “Promise you won't tell!” “I didn't write my name on it!” “Isn't the Internet already anonymous?” 7 Anonymity serves different interests for different user groups. Anonymity “It's privacy!” Private citizens 8 Anonymity serves different interests for different user groups. Anonymity Businesses “It's network security!” “It's privacy!” Private citizens 9 Anonymity serves different interests for different user groups. “It's traffic-analysis resistance!” Governments Anonymity Businesses “It's network security!” “It's privacy!” Private citizens 10 Anonymity serves different interests for different user groups. Human rights “It's reachability!” “It's traffic-analysis activists resistance!” Governments Anonymity Businesses “It's network security!” “It's privacy!” Private citizens 11 Regular citizens don't want to be watched and tracked. -
Peer to Peer Resources
Peer To Peer Resources By Marcus P. Zillman, M.S., A.M.H.A. Executive Director – Virtual Private Library [email protected] This January 2009 column Peer To Peer Resources is a comprehensive list of peer to peer resources, sources and sites available over the Internet and the World Wide Web including peer to peer, file sharing, and grid and matrix search engines. The below list is taken from the peer to peer research section of my Subject Tracer™ Information Blog titled Deep Web Research and is constantly updated with Subject Tracer™ bots at the following URL: http://www.DeepWebResearch.info/ These resources and sources will help you to discover the many pathways available to you through the Internet for obtaining and locating peer to peer sources in todays rapidly changing data procurement society. This is a MUST information keeper for those seeking the latest and greatest peer to peer resources! Peer To Peer Resources: ALPINE Network - SourceForge: Project http://sourceforge.net/projects/alpine/ An Efficient Scheme for Query Processing on Peer-to-Peer Networks http://aeolusres.homestead.com/files/index.html angrycoffee.com http://www.AngryCoffee.com/ Azureus - Vuze Java Bittorrent Client http://azureus.sourceforge.net/ 1 January 2009 Zillman Column – Peer To Peer Resources http://www.zillmancolumns.com/ [email protected] © 2009 Marcus P. Zillman, M.S., A.M.H.A. BadBlue http://badblue.com/ Between Rhizomes and Trees: P2P Information Systems by Bryn Loban http://firstmonday.org/htbin/cgiwrap/bin/ojs/index.php/fm/article/view/1182 -
Monitoring the Dark Web and Securing Onion Services
City University of New York (CUNY) CUNY Academic Works Publications and Research Queensborough Community College 2017 Monitoring the Dark Web and Securing Onion Services John Schriner CUNY Queensborough Community College How does access to this work benefit ou?y Let us know! More information about this work at: https://academicworks.cuny.edu/qb_pubs/41 Discover additional works at: https://academicworks.cuny.edu This work is made publicly available by the City University of New York (CUNY). Contact: [email protected] Monitoring the Dark Web Schriner 1 John Schriner Monitoring the Dark Web Contrary to what one may expect to read with a title like Monitoring the Dark Web, this paper will focus less on how law enforcement works to monitor hidden web sites and services and focus more on how academics and researchers monitor this realm. The paper is divided into three parts: Part One discusses Tor research and how onion services work; Part Two discusses tools that researchers use to monitor the dark web; Part Three tackles the technological, ethical, and social interests at play in securing the dark web. Part One: Tor is Research-Driven Tor (an acronym for 'the onion router' now stylized simply 'Tor') is an anonymity network in which a user of the Tor Browser connects to a website via three hops: a guard node, a middle relay, and an exit node. The connection is encrypted with three layers, stripping a layer at each hop towards its destination server. No single node has the full picture of the connection along the circuit: the guard knows only your IP but not where the destination is; the middle node knows the guard and the exit node; the exit node knows only the middle node and the final destination. -
Analysing the MUTE Anonymous File-Sharing System Using the Pi-Calculus
Analysing the MUTE Anonymous File-Sharing System Using the Pi-calculus Tom Chothia CWI, Kruislaan 413, 1098 SJ, Amsterdam, The Netherlands. Abstract. This paper gives details of a formal analysis of the MUTE system for anonymous file-sharing. We build pi-calculus models of a node that is innocent of sharing files, a node that is guilty of file-sharing and of the network environment. We then test to see if an attacker can dis- tinguish between a connection to a guilty node and a connection to an innocent node. A weak bi-simulation between every guilty network and an innocent network would be required to show possible innocence. We find that such a bi-simulation cannot exist. The point at which the bi- simulation fails leads directly to a previously undiscovered attack on MUTE. We describe a fix for the MUTE system that involves using au- thentication keys as the nodes’ pseudo identities and give details of its addition to the MUTE system. 1 Introduction MUTE is one of the most popular anonymous peer-to-peer file-sharing systems1. Peers, or nodes, using MUTE will connect to a small number of other, known nodes; only the direct neighbours of a node know its IP address. Communication with remote nodes is provided by sending messages hop-to-hop across this overlay network. Routing messages in this way allows MUTE to trade efficient routing for anonymity. There is no way to find the IP address of a remote node, and direct neighbours can achieve a level of anonymity by claiming that they are just forwarding requests and files for other nodes. -
Technical and Legal Overview of the Tor Anonymity Network
Emin Çalışkan, Tomáš Minárik, Anna-Maria Osula Technical and Legal Overview of the Tor Anonymity Network Tallinn 2015 This publication is a product of the NATO Cooperative Cyber Defence Centre of Excellence (the Centre). It does not necessarily reflect the policy or the opinion of the Centre or NATO. The Centre may not be held responsible for any loss or harm arising from the use of information contained in this publication and is not responsible for the content of the external sources, including external websites referenced in this publication. Digital or hard copies of this publication may be produced for internal use within NATO and for personal or educational use when for non- profit and non-commercial purpose, provided that copies bear a full citation. www.ccdcoe.org [email protected] 1 Technical and Legal Overview of the Tor Anonymity Network 1. Introduction .................................................................................................................................... 3 2. Tor and Internet Filtering Circumvention ....................................................................................... 4 2.1. Technical Methods .................................................................................................................. 4 2.1.1. Proxy ................................................................................................................................ 4 2.1.2. Tunnelling/Virtual Private Networks ............................................................................... 5