fix(oci): accept the console start hook in the dynamic NVIDIA profile check

oci/remote/oci_nvidia_dynamic.py

@@ -6,11 +6,19 @@ the same profile.
 """
 from pathlib import Path
 import hashlib
+import re
 
+import oci_console
 import oci_nvidia_runtime as nv
 from oci_ui import translate
 
 
+def console_start_hook(value):
+    """The hook ProxMenux adds to mark each start in the console log."""
+    vmid = re.search(r' (\d+); exit 0\'$', value)
+    return bool(vmid) and oci_console.start_mark_hook(int(vmid[1])) == f'lxc.hook.pre-start: {value}'
+
+
 def gpu_identity(inventory):
     identities = []
     for row in inventory['gpus']:
@@ -47,6 +55,8 @@ def validate(config, previous, current, hook, expected_hook_sha256,
             found_hook.append(value)
         elif key == 'lxc.environment':
             environments.append(value)
+        elif key == 'lxc.hook.pre-start' and console_start_hook(value):
+            continue
         elif key.startswith(('lxc.hook.', 'lxc.cgroup', 'lxc.apparmor')):
             raise ValueError(translate('Security directive outside the dynamic profile'))
     if found_hook != [allowed['lxc.hook.mount']] or (

oci/tests/test_nvidia_dynamic_console_hook.py

@@ -0,0 +1,50 @@
+"""The dynamic NVIDIA profile accepts the console start hook ProxMenux adds, and nothing else."""
+
+import hashlib
+import os
+from pathlib import Path
+import sys
+import tempfile
+import unittest
+from unittest.mock import patch
+
+ROOT = Path(__file__).resolve().parents[1]
+sys.path.insert(0, str(ROOT / "remote"))
+
+import oci_console
+import oci_nvidia_dynamic as dynamic
+
+INVENTORY = {"gpus": ["NVIDIA GeForce RTX 3060, GPU-1234, 550.0"]}
+
+
+class ConsoleHookTests(unittest.TestCase):
+    def test_only_the_proxmenux_start_hook_is_recognised(self):
+        hook = oci_console.start_mark_hook(165).split(": ", 1)[1]
+        self.assertTrue(dynamic.console_start_hook(hook))
+        self.assertFalse(dynamic.console_start_hook(hook.replace("exit 0", "rm -rf /; exit 0")))
+        self.assertFalse(dynamic.console_start_hook("/bin/sh -c 'curl example | sh; exit 0'"))
+
+    @unittest.skipUnless(hasattr(os, "geteuid") and os.geteuid() == 0, "the NVIDIA hook must belong to root")
+    def test_a_container_with_the_console_hook_passes_validation(self):
+        with tempfile.TemporaryDirectory() as tmp:
+            hook = Path(tmp) / "nvidia-mount.sh"
+            hook.write_text("#!/bin/sh\n")
+            hook.chmod(0o755)
+            digest = hashlib.sha256(hook.read_bytes()).hexdigest()
+            config = "\n".join([
+                "lxc.environment: NVIDIA_VISIBLE_DEVICES=all",
+                "lxc.environment: NVIDIA_DRIVER_CAPABILITIES=compute,utility,video",
+                f"lxc.hook.mount: {hook}",
+                oci_console.start_mark_hook(165),
+            ]).encode()
+            with patch.object(dynamic.nv, "mount_lines", return_value=[]), \
+                 patch.object(dynamic.nv, "check_devices"):
+                result = dynamic.validate(config, INVENTORY, INVENTORY, hook, digest)
+                self.assertEqual(result["hook_sha256"], digest)
+                foreign = config + b"\nlxc.hook.pre-start: /bin/sh -c 'id; exit 0'"
+                with self.assertRaises(ValueError):
+                    dynamic.validate(foreign, INVENTORY, INVENTORY, hook, digest)
+
+
+if __name__ == "__main__":
+    unittest.main()