adds threatmodel chapter

docs/index.rst

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    communication
    irc
    tor
+   threatmodel
    opsec
 
 

docs/threatmodel.rst

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+=====================
+Assessing Your Risks
+=====================
+
+.. note:: This chapter is originally from `SURVEILLANCE SELF-DEFENSE <https://ssd.eff.org>`_ guide by `EFF <https://eff.org>`_ under 
+          the `Creative Commons Attribution License <http://creativecommons.org/licenses/by/3.0/us/>`_.
+
+
+Trying to protect all your data from everyone all the time is impractical and
+exhausting. But, do not fear! Security is a process, and through thoughtful
+planning, you can assess what’s right for you. Security isn’t about the tools
+you use or the software you download. It begins with understanding the unique
+threats you face and how you can counter those threats.
+
+In computer security, a threat is a potential event that could undermine your
+efforts to defend your data. You can counter the threats you face by
+determining what you need to protect and from whom you need to protect it.
+This process is called “threat modeling.”
+
+This guide will teach you how to threat model, or how to assess your risks for
+your digital information and how to determine what solutions are best for you.
+
+What might threat modeling look like? Let’s say you want to keep your house
+and possessions safe, here are a few questions you might ask:
+
+What do I have inside my home that is worth protecting?
+--------------------------------------------------------
+
+Assets could include: jewelry, electronics, financial documents, passports, or photos
+
+Who do I want to protect it from?
+----------------------------------
+
+Adversaries could include: burglars, roommates, or guests
+
+
+How likely is it that I will need to protect it?
+-------------------------------------------------
+
+Does my neighborhood have a history of burglaries? How trustworthy are my
+roommates/guests? What are the capabilities of my adversaries? What are the
+risks I should consider?
+
+How bad are the consequences if I fail?
+----------------------------------------
+
+Do I have anything in my house that I cannot replace? Do I have the time or
+money to replace these things? Do I have insurance that covers goods stolen
+from my home? How much trouble am I willing to go through to prevent these
+consequences?
+
+Am I willing to buy a safe for sensitive documents? Can I afford to buy a
+high-quality lock? Do I have time to open a security box at my local bank and
+keep my valuables there?
+
+Once you have asked yourself these questions, you are in a position to assess
+what measures to take. If your possessions are valuable, but the risk of a
+break-in is low, then you may not want to invest too much money in a lock.
+But, if the risk is high, you’ll want to get the best lock on the market, and
+consider adding a security system.
+
+Building a threat model will help you to understand threats that are unique to
+you and to evaluate your assets, your adversaries, and your adversaries'
+capabilities, along with the likelihood of risks you face.
+
+
+What is threat modeling and where do I start?
+==============================================
+
+Threat modeling helps you identify threats to the things you value and
+determine from whom you need to protect them. When building a threat model,
+answer these five questions:
+
+- What do I want to protect?
+- Who do I want to protect it from?
+- How bad are the consequences if I fail?
+- How likely is it that I will need to protect it?
+- How much trouble am I willing to go through to try to prevent potential consequences?
+
+Let’s take a closer look at each of these questions.
+
+What do I want to protect?
+===========================
+
+An **asset** is something you value and want to protect. In the context of
+digital security, an asset is usually some kind of information. For example,
+your emails, contact lists, instant messages, location, and files are all
+possible assets. Your devices may also be assets.
+
+*Make a list of your assets: data that you keep, where it’s kept, who has
+access to it, and what stops others from accessing it.*
+
+Who do I want to protect it from?
+==================================
+
+To answer this question, it’s important to identify who might want to target
+you or your information. A person or entity that poses a threat to your assets
+is an **adversary**. Examples of potential adversaries are your boss, your
+former partner, your business competition, your government, or a hacker on a
+public network.
+
+*Make a list of your adversaries, or those who might want to get ahold of your
+assets. Your list may include individuals, a government agency, or
+corporations.*
+
+.. warning:: Depending on who your adversaries are, under some circumstances this list might be something you want to destroy after you’re done threat modeling.
+
+How bad are the consequences if I fail?
+========================================
+
+There are many ways that an adversary can threaten your data. For example, an
+adversary can read your private communications as they pass through the
+network, or they can delete or corrupt your data.
+
+The motives of adversaries differ widely, as do their attacks. A government
+trying to prevent the spread of a video showing police violence may be content
+to simply delete or reduce the availability of that video. In contrast, a
+political opponent may wish to gain access to secret content and publish that
+content without you knowing.
+
+Threat modeling involves understanding how bad the consequences could be if an
+adversary successfully attacks one of your assets. To determine this, you
+should consider the capability of your adversary. For example, your mobile
+phone provider has access to all your phone records and thus has the
+capability to use that data against you. A hacker on an open Wi-Fi network can
+access your unencrypted communications. Your government might have stronger
+capabilities.
+
+*Write down what your adversary might want to do with your private data.*
+
+
+How likely is it that I will need to protect it?
+==================================================
+
+Risk is the likelihood that a particular threat against a particular asset
+will actually occur. It goes hand-in-hand with capability. While your mobile
+phone provider has the capability to access all of your data, the risk of them
+posting your private data online to harm your reputation is low.
+
+It is important to distinguish between threats and risks. While a threat is a
+bad thing that can happen, risk is the likelihood that the threat will occur.
+For instance, there is a threat that your building might collapse, but the
+risk of this happening is far greater in San Francisco (where earthquakes are
+common) than in Stockholm (where they are not).
+
+Conducting a risk analysis is both a personal and a subjective process; not
+everyone has the same priorities or views threats in the same way. Many people
+find certain threats unacceptable no matter what the risk, because the mere
+presence of the threat at any likelihood is not worth the cost. In other
+cases, people disregard high risks because they don't view the threat as a
+problem.
+
+*Write down which threats you are going to take seriously, and which may be too
+rare or too harmless (or too difficult to combat) to worry about.*
+
+
+How much trouble am I willing to go through to try to prevent potential consequences?
+=======================================================================================
+
+Answering this question requires conducting the risk analysis. Not everyone
+has the same priorities or views threats in the same way.
+
+For example, an attorney representing a client in a national security case
+would probably be willing to go to greater lengths to protect communications
+about that case, such as using encrypted email, than a mother who regularly
+emails her daughter funny cat videos.
+
+*Write down what options you have available to you to help mitigate your unique
+threats. Note if you have any financial constraints, technical constraints, or
+social constraints.*
+
+Threat modeling as a regular practice
+======================================
+
+Keep in mind your threat model can change as your situation changes. Thus,
+conducting frequent threat modeling assessments is good practice.
+
+.. note:: Create your own threat model based on your own unique situation. Then mark your calendar for a date in the future. This will prompt you to review your threat model and check back in to assess whether it’s still relevant to your situation.