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<h1>ACL implementation in docman</h1> |
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|
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<p>ACL implementation in docman is called <b>trustees</b>. It's based on |
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concept of trustees for Linux kernel by Vyacheslav Zavadsky |
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<zavadsky@braysystems.com> |
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</p> |
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|
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<p>Trustees are used to control access right, and special features |
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(like <a href="notify.html">notify on change</a>) |
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</p> |
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|
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<h2>Format of trustee file</h2> |
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|
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<p>Comments are written using hash (#) as first character in line |
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<br><tt># this is a comment</tt></p> |
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|
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<p>Group can be used instead of username in all ACLs. You can't have user |
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which has same name as group or vice-versa. It's written using plus (+) as |
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first character in line. |
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<br>+<i>group</i>:<i>user</i>[,<i>user</i>...]</p> |
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|
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<p>ACL is defined |
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<br><i>path</i>[<i>file</i>]<b>:</b>(<i>user</i>|<i>+group</i>|*)[,<i>user</i>...]:[<i>modifier</i>]<i>permission</i>[:...]</p> |
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|
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Valid modifiers: |
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<ul> |
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<li><tt>!</tt> trustee applies to all except user or group |
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<li><tt>C</tt> clear the permission (default is to set) |
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<li><tt>D</tt> deny access (default is grant) |
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<li><tt>O</tt> one-level trustee only <small>(this means that those permissions |
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will not be inherited on directories and files upwards from current |
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level -- it's usefull for root directory only anonymous access) |
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</ul> |
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|
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Valid permissions: |
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<ul> |
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<li><tt>R</tt> read (file) |
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<li><tt>W</tt> write (file) |
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<li><tt>B</tt> browse (directory) |
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<li><tt>N</tt> <a href="notify.html">notify</a> (e-mail change) |
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</ul> |
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|
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<h2>Examples</h2> |
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|
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<pre> |
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# dpavlin is admin (grant all access to members of root group) |
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+root:dpavlin |
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/:root:RWB |
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# give read-only access to all users |
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/:*:R |
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# anyone can write in this file |
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/public_write.txt:*:w |
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# let just joe access secret file |
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/secret:joe:!CRW |
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</pre> |
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|
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<p>There is major difference between <b>deny</b> and <b>clear</b>. If you |
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want to deny access to one file except to use joe (which should have |
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read-only access) you could write: |
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|
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<pre> |
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/secret.txt:*:DRWB:joe:R |
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</pre> |
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|
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That is wrong. <b>deny</b> rules will take precedence over allow read |
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to joe. So, you should write: |
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|
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<pre> |
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/secret.txt:*:CRWB:joe:R |
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</pre> |
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|
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Which will work. |
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|
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<big>FIX</big> write more examples, better descriptions... |
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|
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<h2>Default security</h2> |
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|
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<p>If none of trustee rules satisfy, default policy is <i>deny</i>. Basically, |
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you have to explicitly allow all your users access to files (which can be |
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as simple as <tt>/:*:RB</tt> to give <i>read</i> and <i>browse</i> to all |
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users) |
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</p> |
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|
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<h2>docman without trustee configuration</h2> |
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|
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<p>If you <b>don't have</b> <tt>realm/http_virtual_host.trustee</tt> you |
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will fall-back to default docman v1.x behavior: whole group will have |
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all right on all files except <i>anonymous</i> users (which won't be able |
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to login anyway). |
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</p> |
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|
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<p>See also: |
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<a href="admin.html">Administration manual</a> |
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</p> |