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== Active Directory made easy ==
[[Category:Docs Project]]
=== GNOME gets along with AD ===
[[Category:Draft documentation]]
Fedora should be able to be used on an Active Directory domain (or other kerberos realms, such as IPA) out of the box. It should be easy to configure domain logins on a Fedora machine, and then it should be intuitive and uneventful to login with those credentials.
[[Category:Documentation beats]]
 
These improvements will also increase reliability and ease usage for any Kerberos realm, not just active directory. Improvement has been made in much of the login and authentication stack, which now includes realmd and adcli.
 
The GNOME "User Accounts" Settings GUI features support for enterprise logins.
 
=== IPA improves AD Support ===
With Fedora 18 it would be possible to create a trust relationship between an IPA and an Active Directory domain which would allow users from one domain to access resource of the other domain.  The FreeIPA project has documented the feature at http://freeipa.org/page/IPAv3_testing_AD_trust.
 
== Secure Boot ==
 
UEFI Secure Boot will be supported in Fedora 18. This will allow Fedora to boot on systems that have Secure Boot enabled. Tools are available for administrators to create custom certificates to sign local changes to GRUB or the kernel.
 
== rngd ==
 
Random number generation is improved by enabling rngd by default.


== Secure Containers ==
== Hardlink and symlink restrictions ==


Using SELinux and '''virt-sandbox''', services can be run in secure sandboxes, even as root. The '''virt-sandbox-service''' package will create mount points and a libvirt container.  
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:


== SELinux boolean renaming ==
fs.protected_hardlinks = 1
fs.protected_symlinks = 1


In order to clarify the purpose of SELinux booleans, all settings that begin with "allow" will be renamed to reflect their domain. Existing policy booleans will continue to be supported.
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,
 
== SELinux Systemd Access Control ==
 
Support has been added to '''systemd''' to check unit files against SELinux settings before allowing a process to start or stop the service.
 
== System calls restricted ==
` The libseccomp library is now available, which provides applications with an easy way to reduce the potential damage of exploits, leveraging kernel syscall filters. Virtual machines benefit from this as QEMU/KVM now uses libseccomp.
 
 
== usermode ==
 
'''usermode''', a wrapper to provide superuser privileges to unprivileged users, is being phased out in favor of '''polkit'''.
 
== Kerberos credentials moved and improved ==
Fedora 18 changes the standard location of Kerberos credential caches to /run/user/$UID in order to increase security and simplify locating the caches for NFSv4.
Fedora's Kerberos support will now allow users to maintain credentials for multiple identities and for the GSSAPI client code to automatically select credentials based on the target service and hostname.
 
== halt, poweroff, reboot Configuration Moved ==
The ability to use halt(8), poweroff(8) and reboot(8) commands by unprivileged users is now controlled using <code>polkit</code>, see the actions in <code>/usr/share/polkit-1/actions/org.freedesktop.login1.policy</code> . The PAM configuration files <code>/etc/pam.d/{halt,poweroff,reboot}</code> are no longer used and their content, if any, is ignored.
 
 
[[Category:Docs Project]]
[[Category:Draft documentation]]
[[Category:Documentation beats]]

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,