Add referencing existing security groups for inbound traffic

[changhyuni]

Issue

#2688

Description

Enable more flexible management of security groups, I add a security group source chaining feature to inbound security groups. This is great for allowing traffic from public IP spaces, but for internal ALBs, it would be ideal to allow inbound traffic from specific security groups. For instance, allowing API Gateway traffic (via VPC Link) to an ALB without exposing the ALB to the entire subnet or VPC. It would be preferable to reference the security group of the VPC Link. Similarly, you might want to allow a specific EC2 instance (not part of the EKS cluster) to connect to an ALB while restricting access for another EC2 instance.

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the docs directory)
• Manually tested
• Made sure the title of the PR is a good description that can go into the release notes

BONUS POINTS checklist: complete for good vibes and maybe prizes?! 🤯

• Backfilled missing tests for code in same general area 🎉
• Refactored something and made the world a better place 🌟

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: changhyuni / name: june (c5d0abc, a0cf1a8)

[k8s-ci-robot]

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[k8s-ci-robot]

Hi @changhyuni. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[shraddhabang]

/ok-to-test

[changhyuni]

@shraddhabang Hi.
Could you take a look at the PR when you have time?

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: changhyuni
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[changhyuni]

/retest

[changhyuni]

/test pull-aws-load-balancer-controller-e2e-test

[changhyuni]

/test pull-aws-load-balancer-controller-unit-test

[k8s-ci-robot]

@changhyuni: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-aws-load-balancer-controller-unit-test	c5d0abc	link	true	/test pull-aws-load-balancer-controller-unit-test
pull-aws-load-balancer-controller-e2e-test	c5d0abc	link	true	/test pull-aws-load-balancer-controller-e2e-test

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository. I understand the commands that are listed here.