THE MONKEYSPHERE
================
-AGENDA
-======
-[x] clowning
-[ ] work
-[x] jrollins will talk and gesture - in progress
+Monkeysphere is authentication layer that allows the sysadmin to
+perform authorization on OpenPGP user identities instead of on keys.
+It also allows end users to authenticate/identify the ssh server they
+are connecting to by checking the sysadmin's certification.
-COMPONENTS
-==========
-* client-side componants
-** "Marmoset": update known_hosts file with public key of server(s):
-*** be responsible for removing keys from the file as key revocation happens
-*** be responsible for updating a key in the file where there is a key replacement
-*** must result in a file that is parsable by the existing ssh client without errors
-*** manual management must be allowed without stomping on it
-*** provide a simple, intelligible, clear policy for key acceptance
-*** questions: should this query keyserver & update known host files? (we already
- have awesome tool that queries keyservers and updates a web of trust (gpg)
-** "Howler": simple script that could be placed as a trigger function (in your .ssh/config)
-*** runs on connection to a certain host
-*** triggers update to known_hosts file then makes connection
-*** proxy-command | pre-hook script | wrapper script
-** "Langur": policy-editor for viewing/editing policies
+* GENERAL GOAL - use openpgp web-of-trust to authenticate ppl for SSH
+* SPECIFIC GOAL - allow openssh to tie into pgp web-of-trust without
+ modifying the openpgp spec, gpg or openssh
+* DESIGN GOALS - authentication, use the existing generic OpenSSH
+ client, the admin can make it default, although end-user should be
+ decide to use monkeysphere or not
+* DESIGN GOAL - use of monkeysphere should not radically change
+ connecting-to-server experience
-* server-side componants
-** "Rhesus" updates a per-user authorized_keys file, instead of updating a
- known_hosts file from a public key by matching a specified user-id (for given
- user: update authkeys file with public keys derived from authorized_uids
- file)
-*** Needs to operate with the same principles that Marmoset client-side does
-** "Tamarin" triggers Rhesus during an attempt to initiate a connection or a scheduler (or both)
-** "Barbary" - policy editor / viewer
+Host identity piece of monkeysphere could be used without buying into
+the user authentication component.
-* common componants
-** Create a ssh keypair from a openpgp keypair
-from ssh_config(5):
- LocalCommand
- Specifies a command to execute on the local machine after suc‐
- cessfully connecting to the server. The command string extends
- to the end of the line, and is executed with /bin/sh. This
- directive is ignored unless PermitLocalCommand has been enabled.
+USE CASE
+========
+Dramatis Personae: http://en.wikipedia.org/wiki/Alice_and_Bob
+Backstory: http://www.conceptlabs.co.uk/alicebob.html
-NOTES
-=====
-* Daniel and Elliot lie. <check>
-* We will use a distributed VCS, each developer will create their own git repository and publish it publically for others to pull from, mail out
-* public project page doesn't perhaps make sense yet
-* approximate goal - using the web of trust to authenticate ppl for SSH
-* outline of various components of monkeysphere
-* M: what does it mean to be in the monkeysphere? not necessarily a great coder.
-* J: interested in seeing project happen, not in actually doing it. anybody can contribute as much as they want.
-* J: if we put the structure in place to work on monkeysphere then we don't have to do anything
-* D: we are not creating
-* understand gpg's keyring better, understanding tools better, building scripts
-* Some debian packages allow automated configuration of config files.
+Bob wants to sign on to the computer "mangabey.example.org" via
+monkeysphere framework. He doesn't yet have access to the machine,
+but he knows Alice, who is the admin of mangabey. Alice and Bob,
+being the conscientious netizens that they are, have already published
+their personal gpg keys to the web of trust, and being good friends,
+have both signed each other's keys and marked each others keys with
+"full" ownertrust.
+When Alice set up mangabey initially, she published an OpenPGP key for
+the machine with the special userid of "ssh://mangabey.example.org".
+She also signed mangabey's OpenPGP key and published this
+certification to commonly-used keyservers. Alice also configured
+mangabey to treat her own key with full ownertrust, so that it knows
+how to identify connecting users.
-* GENERAL GOAL - use openpgp web-of-trust to authenticate ppl for SSH
-* SPECIFIC GOAL - allow openssh to tie into pgp web-of-trust without modifying either openpgp and openssh
-* DESIGN GOALS - authentication, use the existing generic OpenSSH client, the admin can make it default, although end-user should be decide to use monkeysphere or not
-* DESIGN GOAL - use of monkeysphere should not radically change connecting-to-server experience
-* GOAL - pick a monkey-related name for each component
+Now, Alice creates a user account "bob" on mangabey, and puts Bob's
+userid ("Bob <bob@example.org>") in the authorized_user_ids file for
+user bob on mangabey. The monkeysphere automatically (via cron or
+inotify hook) takes each userid in bob's authorized_user_ids file, and
+looks on a keyserver to find all public keys associated with that user
+ID, with the goal of populating the authorized_keys file for
+bob@mangabey.
-Dramatis Personae: http://en.wikipedia.org/wiki/Alice_and_Bob
-Backstory: http://www.conceptlabs.co.uk/alicebob.html
+In particular: for each key found, the server evaluates the calculated
+validity of the specified user ID based on the ownertrust rules it has
+configured ("trust alice's certifications fully", in this example).
+For each key for which the user ID in question is fully-valid, it
+extracts all DSA- or RSA-based primary or secondary keys marked with
+the authentication usage flag, and converts these OpenPGP public keys
+into ssh public keys. These keys are automatically placed into the
+authorized_keys file for bob.
-* Use Case: Bob wants to sign on to the computer "mangabey" via monkeysphere
- framework. He doesn't have access to the machine, but he knows Alice, who is
- the admin of magabey. Alice creates a user bob and puts bob's userid in the
- auth_user_ids file for bob. Tamarin triggers which causes Rhesus to take all
- the things in the auth_userids file, takes those users, look son a keyserver
- finds the public keys for the users, converts the gpg public keys into ssh
- public keys and inserts those into a user_authorized_keys file. Bob goes to
- connect, bob's ssh client which is monkeysphere enbaled, howler is triggered
- which triggers marmoset which looks out into the web of trust and find an
- OpenPGP key that has a userid that matches the URI of magabey. Marmoset checks
- to see if this key for mangabey has been signed by any keys that you trust
- (based on your policy). Has this key been signed by somebody that you trust?
- If yes, connect, if no: abort or fail-through or whatever. Alice has signed
- this uid, so Marmoset says "OK, this server has been verified" it then
- converts the gpg public key into a ssh public key and then adds this gpg key
- to the known_host file. ssh says, "you" are about to connect to magabey and
- you know this is magabey because alice says so and you trust alice". The gpg
- private key of bob has to be converted (somehow, via agent or something) into
- a ssh private_key. SSH connection happens.
+Bob now attempts to connect, by firing up a terminal and invoking:
+"ssh bob@mangabey.example.org". Bob's monkeysphere-enabled ssh client
+notices that mangabey.example.org isn't already available in bob's
+known_hosts file, and fetches the host key for mangabey from the
+public keyservers, with the goal of populating Bob's local known_hosts
+file.
-Host identity piece of monkeysphere could be used without buying into the
-authorization component.
+In particular: the monkeysphere queries its configured keyservers to
+find all public keys with User ID ssh://mangabey.example.org. For
+each public key found, it checks the relevant User ID's validity,
+converts any authentication-capable OpenPGP public keys into ssh
+public keys if the User ID validity is acceptable, and finally insert
+those keys into Bob's known_hosts file.
-Monkeysphere is authentication layer that allows the sysadmin to perform
-authorization on user identities instead of on keys, it additionally allows the
-sysadmin also to authenticate the server to the end-user.
+On Bob's side, since mangabey's key had "full" validity (it was signed
+by Alice, whom he fully trusts), Bob's ssh client deems mangabey
+"known" and no further host key checking is required.
-git clone http://git.mlcastle.net/monkeysphere.git/ monkeysphere
+On mangabey's side, since Bob's key has "full" validity (it had been
+signed by Alice, mangabey's trusted administrator), Bob is
+authenticated and therefore authorized to log into his account.
-Fix gpgkey2ssh so that the entire key fingerprint will work, accept full fingerprint, or accept a pipe and do the conversion
-Write manpage for gpgkey2ssh
-gpg private key (start with passwordless) to PEM encoded private key: perl libraries, libopencdk / gnutls, gpgme
-setup remote git repo
-think through / plan merging of known_hosts (& auth_keys?)
-think about policies and their representation
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projects / monkeysphere.git / blobdiff