Setting Up Subversion for One or Multiple Projects
In the configuration section I mentioned the mod_authz_svn.so module, created and installed by the Subversion installation process. This module allows us to define the access control policy on a directory basis, thus increasing the level of granularity.
Why do we need a separate module to take care of directory-based access control? Couldn't we use Apache configuration primitives? The problem here is the URL passed to Apache to access a repository, which is of the form:
As we can see, only the project path and name is visible: the project's accessed directory is hidden in the numeric code. Thus, we cannot directly apply Apache Location-based access control primitives. The solution consists of delegating directory access control to the mod_authz_svn.so module, which is able to parse the numeric code and identify the accessed directory.
The mod_authz_svn.so's access control policy is specified in a plain-text file with a simple syntax. Here's the one we use for our public projects (/svn/conf/policies/public_svn_authz):
[groups] foo = john, bob bar = john, mike [/] * = r [foo:/] @foo = rw [foo:/branch/john] bob = r [foo:/branch/bob] john = r [bar:/] @bar = rw
We first define the groups of users we want to specify the policy for, then we list the access control rules. The one under the [/] section specifies that any user can read the content of any project. For each project (for example [foo:/]) we specify a global access control policy, specifying it for the inner directories. There's no need to specify an access control rule for user john in the /branch/john directory, because it's inherited from the one in the upper-level directory.
In addition, we had to specify again the different groups' composition. We should avoid replication of such configuration directives as a good security practice. This problem is solved simply by removing any AuthGroupFile directive from the project configuration files and changing the related Require directive to a Require valid-user one, thus delegating group management to the mod_authz_svn.so module.
At this point all that remains is to add the directive AuthzSVNAccessFile to the default policy files in order to tell Apache that we intend to use the mod_authz_svn.so module as an access control facility. To do so, we must specify its configuration file. Here's the one for public projects:
<Location /public> Dav svn SVNParentPath /tmp/LJ/svn/repository/public <LimitExcept GET PROPFIND OPTIONS REPORT> Order deny,allow Deny from all Allow from 127.0.0.1 Satisfy all </LimitExcept> AuthzSVNAccessFile /tmp/LJ/svn/conf/public_svn_authz </Location> <VirtualHost _default_:8081> <Location /public> Dav svn SVNParentPath /tmp/LJ/svn/repository/public Order allow,deny Allow from all <LimitExcept GET PROPFIND OPTIONS REPORT> Order deny,allow Deny from all Satisfy all </LimitExcept> AuthzSVNAccessFile /tmp/LJ/svn/conf/public_svn_authz </Location> Include /tmp/LJ/svn/conf/policies/public/* </VirtualHost>
You may ask why we didn't use the mod_authz_svn.so module before. If we hadn't any trusted subnets, we could throw away most of the Apache access control machinery and rely solely on the mod_authz_svn.so, even if this is true only from Subversion 1.0.1. But because mod_authz_svn.so's access control strategy is user-based when in the scenario with a trusted subnet, we need a mix of source-based access control and user-based access control.
|Chemistry on the Desktop||Mar 23, 2017|
|Five HPC Cost Considerations to Maximize ROI||Mar 23, 2017|
|Two Ways GDPR Will Change Your Data Storage Solution||Mar 22, 2017|
|Android Candy: That App Is for the Birds!||Mar 22, 2017|
|Hodge Podge||Mar 21, 2017|
|William Rothwell and Nick Garner's Certified Ethical Hacker Complete Video Course (Pearson IT Certification)||Mar 20, 2017|
- Chemistry on the Desktop
- Five HPC Cost Considerations to Maximize ROI
- Preseeding Full Disk Encryption
- Hodge Podge
- William Rothwell and Nick Garner's Certified Ethical Hacker Complete Video Course (Pearson IT Certification)
- Two Factors Are Better Than One
- Two Ways GDPR Will Change Your Data Storage Solution
- GRUB Boot from ISO
- Minifree Ltd.'s GNU+Linux Computers
- Flash ROMs with a Raspberry Pi
Pick up any e-commerce web or mobile app today, and you’ll be holding a mashup of interconnected applications and services from a variety of different providers. For instance, when you connect to Amazon’s e-commerce app, cookies, tags and pixels that are monitored by solutions like Exact Target, BazaarVoice, Bing, Shopzilla, Liveramp and Google Tag Manager track every action you take. You’re presented with special offers and coupons based on your viewing and buying patterns. If you find something you want for your birthday, a third party manages your wish list, which you can share through multiple social- media outlets or email to a friend. When you select something to buy, you find yourself presented with similar items as kind suggestions. And when you finally check out, you’re offered the ability to pay with promo codes, gifts cards, PayPal or a variety of credit cards.Get the Guide