Re: [PATCH v5] secilc/docs: document expandtypeattribute

[James Carter <jwcart2@gmail.com>]

On Wed, Aug 5, 2020 at 3:50 PM Dominick Grift
<dominick.grift@defensec.nl> wrote:
>
> This was added for Androids Treble in 2017.
>
> Signed-off-by: Dominick Grift <dominick.grift@defensec.nl>

Acked-by: James Carter <jwcart2@gmail.com>

> ---
> v2: overriden is overridden
> v3: add link to README.md
> v4: rephrase and add another example
> v5: use description from James Carter
>
>  secilc/docs/README.md              |  1 +
>  secilc/docs/cil_type_statements.md | 51 ++++++++++++++++++++++++++++++
>  2 files changed, 52 insertions(+)
>
> diff --git a/secilc/docs/README.md b/secilc/docs/README.md
> index 3f1838e6..efab2a71 100644
> --- a/secilc/docs/README.md
> +++ b/secilc/docs/README.md
> @@ -126,6 +126,7 @@ CIL (Common Intermediate Language)
>    * [typealiasactual](cil_type_statements.md#typealiasactual)
>    * [typeattribute](cil_type_statements.md#typeattribute)
>    * [typeattributeset](cil_type_statements.md#typeattributeset)
> +  * [expandtypeattribute](cil_type_statements.md#expandtypeattribute)
>    * [typebounds](cil_type_statements.md#typebounds)
>    * [typechange](cil_type_statements.md#typechange)
>    * [typemember](cil_type_statements.md#typemember)
> diff --git a/secilc/docs/cil_type_statements.md b/secilc/docs/cil_type_statements.md
> index f9dd3a76..432cede5 100644
> --- a/secilc/docs/cil_type_statements.md
> +++ b/secilc/docs/cil_type_statements.md
> @@ -213,6 +213,57 @@ This example is equivalent to `{ domain -kernel.process -ueventd.process -init.p
>          )
>      )
>
> +expandtypeattribute
> +-------------------
> +
> +Overrides the compiler defaults for the expansion of one or more
> +previously declared [`typeattribute`](cil_type_statements.md#typeattribute)
> +identifiers.
> +
> +This rule gives more control over type attribute expansion and
> +removal. When the value is true, all rules involving the type
> +attribute will be expanded and the type attribute will be removed from
> +the policy. When the value is false, the type attribute will not be
> +removed from the policy, even if the default expand rules or "-X"
> +option cause the rules involving the type attribute to be expanded.
> +
> +**Statement definition:**
> +
> +    (expandtypeattribute typeattribute_id expand_value)
> +
> +**Where:**
> +
> +<table>
> +<colgroup>
> +<col width="25%" />
> +<col width="75%" />
> +</colgroup>
> +<tbody>
> +<tr class="odd">
> +<td align="left"><p><code>expandtypeattribute</code></p></td>
> +<td align="left"><p>The <code>expandtypeattribute</code> keyword.</p></td>
> +</tr>
> +<tr class="even">
> +<td align="left"><p><code>typeattribute_id</code></p></td>
> +<td align="left"><p>One or more previously declared <code>typeattribute</code> identifiers. Multiple entries consist of a space separated list enclosed in parentheses '()'.</p></td>
> +</tr>
> +<tr class="odd">
> +<td align="left"><p><code>expand_value</code></p></td>
> +<td align="left"><p>Either true or false.</p></td>
> +</tr>
> +</tbody>
> +</table>
> +
> +**Examples:**
> +
> +This example uses the expandtypeattribute statement to forcibly expand a previously declared `domain` type attribute.
> +
> +    (expandtypeattribute domain true)
> +
> +This example uses the expandtypeattribute statement to not expand previously declared `file_type` and `port_type` type attributes regardless of compiler defaults.
> +
> +    (expandtypeattribute (file_type port_type) false)
> +
>  typebounds
>  ----------
>
> --
> 2.28.0
>