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== Hardlink and symlink restrictions ==
! style="width: 70%;" |Toool || style="width: 10%; text-align: center;" | To do || Writer
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|style="text-align: left;" | [[Features/DynamicFirewall | Dynamic Firewall]] || done ||
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|style="text-align: left;"| [[Features/DNSSEC_on_workstations | DNSSEC on workstations]] || done ||
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|style="text-align: left;"| OpenSCAP (secstat, firstaidkit) || done ||
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|style="text-align: left;"| [[Features/EcryptfsAuthConfig | EcryptfsAuthConfig]] || done ||
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|style="text-align: left;" | [[Features/RemoveSETUID |Remove SETUID]] (for pkgs maintainers)|| done ||
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|style="text-align: left;"| [http://0pointer.de/public/systemd-man/pam_systemd.html pam_systemd] (systemd related) || ??? ||
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|style="text-align: left;"| freeipa (F15) || ??? ||
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|}
 
= Security =
This section describes the security changes and enhancements available in Fedora 15. 
 
== Dynamic Firewall ==
Fedora 15 adds support for the optional firewall daemon (FirewallD), providing a dynamic firewall management with a D-Bus interface.
 
The previous firewall model with system-config-firewall, was static and required a full firewall restart for all changes, even simple ones. The dynamic firewall mode, makes it possible to change firewall settings without the need to restart the firewall for persistent connections. At this stage, it supports iptables, ip6table and ebtables. In Fedora 15 a simple tray applet shows the firewall state, enabling/disabling firewall services
 
For more details, visit the Fedora wiki pages, https://fedoraproject.org/wiki/Features/DynamicFirewall and https://fedoraproject.org/wiki/Features/FirewallD/.
 
 
== DNSSEC on workstations  ==
In Fedora 15 comes in a new security feature that protects the end users and their workstations exposition against various DNS spoofing and DNS cache-poisoning attacks.
 
'''DNSSEC''' is an environment full tested in Fedora, as all major DNS servers in Fedora run with '''DNSSEC''' validation enabled by default since Fedora 11, giving to the Fedora Project a lot of experience from server environment. '''DNSSEC''' is aimed to secure all DNS traffic. <code>NetworkManager</code> uses the BIND nameserver as a DNSSEC resolver and all received DNS responses are proved to be correct. In case a particular domain is signed and failed to validate then resolver returns SERFVAIL instead of invalidated response, which means something is wrong.
 
For all details refer to https://fedoraproject.org/wiki/Features/DNSSEC_on_workstations on the Fedora wiki.
 
'''dnssec-tools''' version 1.8 in Fedora 15 is the tool used to improve this feature.
 
 
== OpenSCAP ==
First introduced in Fedora 14, OpenSCAP is a set of open source libraries providing an easier path for integration of the SCAP line of standards, managed by NIST and created to provide a standardized approach to maintaining the security of enterprise systems, such as automatically verifying the presence of patches, checking system security configuration settings, and examining systems for signs of compromise.
 
In Fedora 15, '''openscap''', the set of open source libraries enabling integration of the SCAP line of standards, has been upgraded from version 0.6.3 to 0.6.8. During these development stage there has been introduced full support for perl regular expression by default, OVAL float type support, XSL transformation improvements and Dublin Core support, added OVAL schemas version 5.6 and improved XCCDF reporting.
 
'''secstate''', the Security State Configuration Tool, has been rebuilt in Fedora 15 against version 0.4.1.
'''firstaidkit''', the System Rescue Tool that automates simple and common system recovery tasks, has been upgraded from 0.2.17 to version 0.2.18.


For more informations visit this page [http://www.open-scap.org/page/Main_Page http://www.open-scap.org/page/Main_Page].
A long-standing class of security issues is the link-based time-of-check-time-of-use race, most commonly seen in world-writable directories like /tmp. The common method of exploitation of this flaw is to cross privilege boundaries when following a given link (i.e. a root process follows a link belonging to another user). In Fedora 19,  we permit links to only be followed when outside a sticky world-writable directory, or when the uid of the link and follower match, or when the directory owner matches the link's owner. In previous releases, this was enforced by SELinux policy and in this release, we have enabled these restrictions via the following sysctl settings in /usr/lib/sysctl.d/00-system.conf as an additional layer of protection:


fs.protected_hardlinks = 1
fs.protected_symlinks = 1


== authoconfig ecryptfs ==
Refer to http://lwn.net/Articles/503660/ and https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=800179c9b8a1e796e441674776d11cd4c05d61d7 for more detailed information about this change. Note that in addition to this,
('''Feature Not confirmed''')
 
Fedora 15 brings in improved support for eCryptfs, a stacked cryptographic filesystem for Linux. '''ecryptfs''' is a useful tool that allows system administrator automatically <code>authconfig</code> and mount a private encrypted part of the home directory when a user logs in.
 
For details refer to the wiki page https://fedoraproject.org/wiki/Features/EcryptfsAuthConfig.
 
 
== For Package Maintainers ==
('''perhaps don't include in the RN''')
 
Another feature that makes the applications and the Operating System more secure. Fedora 15 removes setuid applications and instead specifically assigns the capabilities required by an application, modifing the spec files of most applications that include a setuid application to remove the setuid flag and change to file capabilities.
 
Refer to https://fedoraproject.org/wiki/Features/RemoveSETUID for all details.
 
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Revision as of 14:10, 20 March 2013

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Hardlink and symlink restrictions

A long-standing class of security issues is the link-based time-of-check-time-of-use race, most commonly seen in world-writable directories like /tmp. The common method of exploitation of this flaw is to cross privilege boundaries when following a given link (i.e. a root process follows a link belonging to another user). In Fedora 19, we permit links to only be followed when outside a sticky world-writable directory, or when the uid of the link and follower match, or when the directory owner matches the link's owner. In previous releases, this was enforced by SELinux policy and in this release, we have enabled these restrictions via the following sysctl settings in /usr/lib/sysctl.d/00-system.conf as an additional layer of protection:

fs.protected_hardlinks = 1
fs.protected_symlinks = 1

Refer to http://lwn.net/Articles/503660/ and https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=800179c9b8a1e796e441674776d11cd4c05d61d7 for more detailed information about this change. Note that in addition to this,