Awesome

Terraform Parliament - Run Parliament AWS IAM Checker on Terraform Files

Parliament checks IAM policy validity against the latest AWS IAM specifications, so e.g. It'll pick up if your policy uses an older Action like billing:*, instead of the current aws-portal:*

By default, Parliament runs only on JSON IAM policies, not Terraform files. However I wanted to validate my Terraform files.

This utility parses your Terraform, finds aws_iam_policy_document elements, generates resulting IAM policy document strings, and runs Parliament on them.

It stubs any Terraform interpolations ${...} so they can be evaluated by Parliament as valid JSON.

Example run

Terraform Resource Support

Resource Type	Supported?
`aws_iam_policy`	Yes only inline policy not file()
`aws_iam_policy_document`	Yes
`aws_iam_user_policy`	No
`aws_iam_group_policy`	No
`aws_iam_role_policy`	No
`aws_s3_bucket_policy`	No
`aws_[ecr\|efs\|iot\|media_store_container\|organizations]*_policy`	No
`data.template_file`	No

The unsupported resource types should be pretty easy to add, if anyone feels a PR coming on :)

Issues

Sometimes the interpolation stubbing (e.g. "Replace all ${...} in a Resource with *") results in invalid values; needs to be more sophisticated than current regex replace
No unit tests :(
Currently not fit to be used as a GitHub action (as was my plan) since --recursive not yet implemented
You will receive RESOURCE_MISMATCH if you have a policy with action Get* and resource ending in /* (referring to objects in a bucket), since s3:Get* includes some permissions which are bucket-level, not object-level. I have tried allowing you to ignore this by implementing config override per Parliament doco, and calling parliament.override_config(), to no avail
aws_iam_policy is supported, but only inline policy; not file()
data.template_file not supported

Usage

Docker

DockerHub Repo

Use /github/workspace/ to mount the directory containing the Terraform, since this image is intended to run as a GitHub action:

Intention	Command
Run on the entire directory	`docker run --rm -ti -v (pwd):/github/workspace/ rdkls/tf-parliament`
Run on one file	`docker run --rm -ti -v (pwd):/github/workspace/ rdkls/tf-parliament iam.tf`
Run on some TF files only	`docker run --rm -ti -v (pwd):/github/workspace/ rdkls/tf-parliament 'iam-*.tf'`

Notes

These examples use fish shell (pwd), in bash switch that to `pwd`
Quotes around the argument in the last example, to avoid your shell expanding the wildcard before passing to docker.

Native

pip install -r requirements.txt

tf-parliament.py my-template.tf

(also supports wildcards & directories per Docker method)

Requirements

Docker
Terraform Files v0.12+ (though v0.11 should work too)