[PATCH v11 12/12] landlock: Document Landlock's network support

[Mickaël Salaün]

On 15/05/2023 18:13, Konstantin Meskhidze wrote:
> Describe network access rules for TCP sockets. Add network access
> example in the tutorial. Add kernel configuration support for network.
> 
> Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze at huawei.com>
> ---
> 
> Changes since v10:
> * Fixes documentaion as Mickaёl suggested:
> https://lore.kernel.org/linux-security-module/ec23be77-566e-c8fd-179e-f50e025ac2cf@digikod.net/
> 
> Changes since v9:
> * Minor refactoring.
> 
> Changes since v8:
> * Minor refactoring.
> 
> Changes since v7:
> * Fixes documentaion logic errors and typos as Mickaёl suggested:
> https://lore.kernel.org/netdev/9f354862-2bc3-39ea-92fd-53803d9bbc21@digikod.net/
> 
> Changes since v6:
> * Adds network support documentaion.
> 
> ---
>   Documentation/userspace-api/landlock.rst | 83 ++++++++++++++++++------
>   1 file changed, 62 insertions(+), 21 deletions(-)
> 

[...]

> @@ -143,10 +159,23 @@ for the ruleset creation, by filtering access rights according to the Landlock
>   ABI version.  In this example, this is not required because all of the requested
>   ``allowed_access`` rights are already available in ABI 1.
> 
> -We now have a ruleset with one rule allowing read access to ``/usr`` while
> -denying all other handled accesses for the filesystem.  The next step is to
> -restrict the current thread from gaining more privileges (e.g. thanks to a SUID
> -binary).
> +For network access-control, we can add a set of rules that allow to use a port
> +number for a specific action: HTTPS connections.
> +
> +.. code-block:: c
> +
> +    struct landlock_net_service_attr net_service = {
> +        .allowed_access = NET_CONNECT_TCP,

LANDLOCK_ACCESS_NET_CONNECT_TCP


> +        .port = 443,
> +    };
> +
> +    err = landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_SERVICE,
> +                            &net_service, 0);
> +