[libvirt] [PATCH v2 3/5] virt-aa-helper: generate rules for passthrough input devices

[Christian Ehrhardt]

Input devices can passthrough an event device. This currently works only via
hotplug where the AppArmor label is created via the domain label callbacks.

This adds the virt-aa-helper support for passthrough input devices to generate
rules for the needed paths from the initial guest definition as well.

Example in domain xml:
  <input type='passthrough' bus='virtio'>
          <source evdev='/dev/input/event0' />
  </input>
Works to start now and creates:
  "/dev/input/event0" rw,

Fixes: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1757085

Signed-off-by: Christian Ehrhardt <christian.ehrhardt at canonical.com>
---
 src/security/virt-aa-helper.c | 8 ++++++++
 tests/virt-aa-helper-test     | 3 +++
 2 files changed, 11 insertions(+)

diff --git a/src/security/virt-aa-helper.c b/src/security/virt-aa-helper.c
index 456cfce..ad1371d 100644
--- a/src/security/virt-aa-helper.c
+++ b/src/security/virt-aa-helper.c
@@ -1157,6 +1157,14 @@ get_files(vahControl * ctl)
         }
     }
 
+    for (i = 0; i < ctl->def->ninputs; i++) {
+        if (ctl->def->inputs[i] &&
+                ctl->def->inputs[i]->type == VIR_DOMAIN_INPUT_TYPE_PASSTHROUGH) {
+            if (vah_add_file(&buf, ctl->def->inputs[i]->source.evdev, "rw") != 0)
+                goto cleanup;
+        }
+    }
+
     for (i = 0; i < ctl->def->nnets; i++) {
         if (ctl->def->nets[i] &&
                 ctl->def->nets[i]->type == VIR_DOMAIN_NET_TYPE_VHOSTUSER &&
diff --git a/tests/virt-aa-helper-test b/tests/virt-aa-helper-test
index 1e96b8e..054269c 100755
--- a/tests/virt-aa-helper-test
+++ b/tests/virt-aa-helper-test
@@ -359,6 +359,9 @@ testme "0" "hugepages" "-r -u $valid_uuid -F /run/hugepages/kvm/\*\*" "$test_xml
 sed -e "s,###UUID###,$uuid,g" -e "s,###DISK###,$disk1,g" -e "s,<graphics.*>,<graphics type='vnc' socket='/var/lib/libvirt/qemu/myself.vnc'><listen type='address' address='0.0.0.0'/></graphics>,g" "$template_xml" > "$test_xml"
 testme "0" "vnc socket" "-r -u $valid_uuid" "$test_xml"
 
+sed -e "s,###UUID###,$uuid,g" -e "s,###DISK###,$disk1,g" -e "s,</devices>,<input type='passthrough' bus='virtio'><source evdev='$disk2' /></input></devices>,g" "$template_xml" > "$test_xml"
+testme "0" "input dev passthrough" "-r -u $valid_uuid" "$test_xml"
+
 testme "0" "help" "-h"
 
 echo "" >$output
-- 
2.7.4