This new unit settings allows restricting which address families are
available to processes. This is an effective way to minimize the attack
surface of services, by turning off entire network stacks for them.
This is based on seccomp, and does not work on x86-32, since seccomp
cannot filter socketcall() syscalls on that platform.
This permit to switch to a specific apparmor profile when starting a daemon. This
will result in a non operation if apparmor is disabled.
It also add a new build requirement on libapparmor for using this feature.
Issues fixed:
* missing words required by grammar
* duplicated or extraneous words
* inappropriate forms (e.g. singular/plural), and declinations
* orthographic misspellings
Actually 'STDOUT' is something that doesn't appear anywhere: in the
stdlib we have 'stdin', and there's only the constant STDOUT_FILENO,
so there's no reason to use capitals. When refering to code,
STDOUT/STDOUT/STDERR are replaced with stdin/stdout/stderr, and in
other places they are replaced with normal phrases like standard
output, etc.
* standardize capitalization of STDIN, STDOUT, and STDERR
* reword some sentences for clarity
* reflow some very long lines to be shorter than ~80 characters
* add some missing <literal>, <constant>, <varname>, <option>, and <filename> tags
- Allow configuration of an errno error to return from blacklisted
syscalls, instead of immediately terminating a process.
- Fix parsing logic when libseccomp support is turned off
- Only keep the actual syscall set in the ExecContext, and generate the
string version only on demand.
Let's always call the security labels the same way:
SMACK: "Smack Label"
SELINUX: "SELinux Security Context"
And the low-level encapsulation is called "seclabel". Now let's hope we
stick to this vocabulary in future, too, and don't mix "label"s and
"security contexts" and so on wildly.
This permit to let system administrators decide of the domain of a service.
This can be used with templated units to have each service in a différent
domain ( for example, a per customer database, using MLS or anything ),
or can be used to force a non selinux enabled system (jvm, erlang, etc)
to start in a different domain for each service.
Similar to PrivateNetwork=, PrivateTmp= introduce PrivateDevices= that
sets up a private /dev with only the API pseudo-devices like /dev/null,
/dev/zero, /dev/random, but not any physical devices in them.
This is a recurring submission and includes corrections to:
- missing words, preposition choice.
- change of /lib to /usr/lib, because that is what most distros are
using as the system-wide location for systemd/udev files.