# This publication is intellectual property of Canonical Ltd. Its contents
# can be duplicated, either in part or in whole, provided that a copyright
# label is visibly located on each copy.
#
# All information found in this book has been compiled with utmost
# attention to detail. However, this does not guarantee complete accuracy.
# Neither Canonical Ltd, the authors, nor the translators shall be held
# liable for possible errors or the consequences thereof.
#
# Many of the software and hardware descriptions cited in this book
# are registered trademarks. All trade names are subject to copyright
# restrictions and may be registered trade marks. Canonical Ltd.
# essentially adhere to the manufacturer's spelling.
#
# Names of products and trademarks appearing in this book (with or without
# specific notation) are likewise subject to trademark and trade protection
# laws and may thus fall under copyright restrictions.
#


=pod

=head1 NAME

aa_getprocattr_raw, aa_getprocattr - read and parse procattr data

aa_getcon, aa_gettaskcon - get task confinement information

aa_getpeercon - get the confinement of a socket's other end (peer)

=head1 SYNOPSIS

B<#include E<lt>sys/apparmor.hE<gt>>

B<int aa_getprocattr_raw(pid_t tid, const char *attr, char *buf, int len, char **mode);>

B<int aa_getprocattr(pid_t tid, const char *attr, char **label, char **mode);>

B<int aa_gettaskcon(pid_t target, char **label, char **mode);>

B<int aa_getcon(char **label, char **mode);>

B<int aa_getpeercon_raw(int fd, char *buf, int *len, char **mode);>

B<int aa_getpeercon(int fd, char **label, char **mode);>

Link with B<-lapparmor> when compiling.

=head1 DESCRIPTION

The aa_getcon function gets the current AppArmor confinement context for the
current task. The confinement context consists of a label and a mode. The label
is usually just the name of the AppArmor profile restricting the task, but it
may include the profile namespace or in some cases a set of profile names
(known as a stack of profiles). The mode is a string that describes how the
kernel is enforcing the policy defined in the profile. Profiles loaded in
"enforce" mode will result in enforcement of the policy defined in the profile
as well as reporting policy violation attempts. Profiles in "complain" mode
will not enforce policy but instead report policy violation attempts.

Some examples of possible returned *label strings are "unconfined", "/sbin/dhclient",
and "Firefox". The string can consist of any non-NUL characters but it will be
NUL-terminated. The *label string must be freed using free().

The possible *mode strings are "enforce" and "complain". Additionally, *mode may
be NULL when *label is "unconfined". B<The *mode string must not be freed>. The
*label and *mode strings come from a single buffer allocation and are separated
by a NUL character.

The aa_gettaskcon function is like the aa_getcon function except it will work
for any arbitrary task in the system.

The aa_getpeercon function is similar to that of aa_gettaskcon except that
it returns the confinement information for task on the other end of a socket
connection.

The aa_getpeercon_raw function is the backend for the aa_getpeercon function
and does not handle buffer allocation.

The aa_getprocattr function is the backend for the aa_getcon and aa_gettaskcon
functions and handles the reading and parsing of the confinement data from
different arbitrary attr files and returns the processed results in
an allocated buffer.

The aa_getprocattr_raw() is the backend for the aa_getprocattr function and
does not handle buffer allocation.

=head1 RETURN VALUE

On success size of data placed in the buffer is returned, this includes the
mode if present and any terminating characters. On error, -1 is returned, and
errno(3) is set appropriately.

=head1 ERRORS

=over 4

=item B<EINVAL>

The apparmor kernel module is not loaded or the communication via the
F</proc/*/attr/file> did not conform to protocol.

=item B<ENOMEM>

Insufficient kernel memory was available.

=item B<EACCES>

Access to the specified I<file/task> was denied.

=item B<ENOENT>

The specified I<file/task> does not exist or is not visible.

=item B<ERANGE>

The confinement data is too large to fit in the supplied buffer.

=item B<ENOPROTOOPT>

The kernel doesn't support the SO_PEERLABEL option in sockets. This happens
mainly when the kernel lacks 'fine grained unix mediation' support. It also
can happen on LSM stacking kernels where another LSM has claimed this
interface and decides to return this error, although this is really a
corner case.

=back

=head1 NOTES

If aa_getpeercon_raw returns -1 and errno is ERANGE, the value of *len can be
used to reallocate buf so that it is sufficiently large enough to store the
confinement data.

=head1 BUGS

None known. If you find any, please report them at
L<https://gitlab.com/apparmor/apparmor/-/issues>.

=head1 SEE ALSO

apparmor(7), apparmor.d(5), apparmor_parser(8), aa_change_profile(2),
aa_splitcon(3) and L<https://wiki.apparmor.net>.

=cut
