From dd05dbe742384dd22f4a63889c56cb75e4e2f571 Mon Sep 17 00:00:00 2001

From: Vit Mojzis <vmojzis@redhat.com>

Date: Tue, 9 Nov 2021 18:04:39 +0100

Subject: [PATCH] Make sure each section of the inspect exists before accessing

Fixes: https://github.com/containers/udica/issues/105,

       https://github.com/containers/udica/issues/103

Inspired by:

https://github.com/WellIDKRealy/udica/commit/0c56d98b8c58a8a4ceb89b04d700c834c13778fd

Signed-off-by: Vit Mojzis <vmojzis@redhat.com>

---

 udica/parse.py | 62 ++++++++++++++++++++++++++++++++++++++------------

 1 file changed, 48 insertions(+), 14 deletions(-)

diff --git a/udica/parse.py b/udica/parse.py

index 0797095..59b3dc5 100644

--- a/udica/parse.py

+++ b/udica/parse.py

@@ -29,6 +29,24 @@ ENGINE_DOCKER = "docker"

 ENGINE_ALL = [ENGINE_PODMAN, ENGINE_CRIO, ENGINE_DOCKER]

+# Decorator for verifying that getting value from "data" won't

+# result in Key error or Type error

+# e.g. in data[0]["HostConfig"]["Devices"]

+# missing "HostConfig" key in data[0] produces KeyError and

+# data[0]["HostConfig"] == none produces TypeError

+def getter_decorator(function):

+    # Verify that each element in path exists and return the corresponding value,

+    # otherwise return [] -- can be safely processed by iterators

+    def wrapper(self, data, *args):

+        try:

+            value = function(self, data, *args)

+            return value if value else []

+        except (KeyError, TypeError):

+            return []

+

+    return wrapper

+

+

 def json_is_podman_or_docker_format(json_rep):

     """Check if the inspected file is in a format from docker or podman.

@@ -91,19 +109,22 @@ class EngineHelper(abc.ABC):

     def get_caps(self, data, opts):

         if opts["Caps"]:

-            if opts["Caps"] == "None":

+            if opts["Caps"] in ["None", "none"]:

                 return []

             return opts["Caps"].split(",")

         return []

 class PodmanDockerHelper(EngineHelper):

+    @getter_decorator

     def get_devices(self, data):

         return data[0]["HostConfig"]["Devices"]

+    @getter_decorator

     def get_mounts(self, data):

         return data[0]["Mounts"]

+    @getter_decorator

     def get_ports(self, data):

         ports = []

         for key, value in data[0]["NetworkSettings"]["Ports"].items():

@@ -120,8 +141,13 @@ class PodmanHelper(PodmanDockerHelper):

     def __init__(self):

         super().__init__(ENGINE_PODMAN)

+    @getter_decorator

     def get_caps(self, data, opts):

-        if not opts["Caps"]:

+        if opts["Caps"]:

+            return (

+                opts["Caps"].split(",") if opts["Caps"] not in ["None", "none"] else []

+            )

+        else:

             return data[0]["EffectiveCaps"]

         return []

@@ -138,18 +164,25 @@ class DockerHelper(PodmanDockerHelper):

     def adjust_json_from_docker(self, json_rep):

         """If the json comes from a docker call, we need to adjust it to make use

         of it."""

-

-        if not isinstance(json_rep[0]["NetworkSettings"]["Ports"], dict):

-            raise Exception(

-                "Error parsing docker engine inspection JSON structure, try to specify container engine using '--container-engine' parameter"

-            )

-

-        for item in json_rep[0]["Mounts"]:

-            item["source"] = item["Source"]

-            if item["Mode"] == "rw":

-                item["options"] = "rw"

-            if item["Mode"] == "ro":

-                item["options"] = "ro"

+        try:

+            if not isinstance(json_rep[0]["NetworkSettings"]["Ports"], dict):

+                raise Exception(

+                    "Error parsing docker engine inspection JSON structure, try to specify container engine using '--container-engine' parameter"

+                )

+        except (KeyError, TypeError):

+            # "Ports" not specified in given json file

+            pass

+

+        try:

+            for item in json_rep[0]["Mounts"]:

+                item["source"] = item["Source"]

+                if item["Mode"] == "rw":

+                    item["options"] = "rw"

+                if item["Mode"] == "ro":

+                    item["options"] = "ro"

+        except (KeyError, TypeError):

+            # "Mounts" not specified in given json file

+            pass

 class CrioHelper(EngineHelper):

@@ -161,6 +194,7 @@ class CrioHelper(EngineHelper):

         # bind mounting device on the container

         return []

+    @getter_decorator

     def get_mounts(self, data):

         return data["status"]["mounts"]

-- 

2.30.2