Add support for /32 (/128) networks and perNodeBlockSize 1

[ykulazhenkov]

Add support for single IP ranges/subnets in all places:

IPPool perNodeBlockSize 1

apiVersion: nv-ipam.nvidia.com/v1alpha1
kind: IPPool
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"nv-ipam.nvidia.com/v1alpha1","kind":"IPPool","metadata":{"annotations":{},"name":"pool1","namespace":"kube-system"},"spec":{"gateway":"192.168.0.3","perNodeBlockSize":1,"subnet":"192.168.0.0/24"}}
  creationTimestamp: "2024-10-14T16:44:59Z"
  generation: 15
  name: pool1
  namespace: kube-system
  resourceVersion: "16150"
  uid: b43c059a-9364-4fbc-b945-1a1f017ddb1b
spec:
  gateway: 192.168.0.3
  perNodeBlockSize: 1
  subnet: 192.168.0.0/24
status:
  allocations:
  - endIP: 192.168.0.2
    nodeName: kind-control-plane
    startIP: 192.168.0.2
  - endIP: 192.168.0.1
    nodeName: kind-worker
    startIP: 192.168.0.1
  - endIP: 192.168.0.4
    nodeName: kind-worker2
    startIP: 192.168.0.4
  - endIP: 192.168.0.5
    nodeName: kind-worker3
    startIP: 192.168.0.5

IPPool /32

apiVersion: nv-ipam.nvidia.com/v1alpha1
kind: IPPool
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"nv-ipam.nvidia.com/v1alpha1","kind":"IPPool","metadata":{"annotations":{},"name":"pool1","namespace":"kube-system"},"spec":{"perNodeBlockSize":1,"subnet":"192.168.1.1/32"}}
  creationTimestamp: "2024-10-14T16:44:59Z"
  generation: 16
  name: pool1
  namespace: kube-system
  resourceVersion: "16441"
  uid: b43c059a-9364-4fbc-b945-1a1f017ddb1b
spec:
  perNodeBlockSize: 1
  subnet: 192.168.1.1/32
status:
  allocations:
  - endIP: 192.168.1.1
    nodeName: kind-control-plane
    startIP: 192.168.1.1

IPPool /31

apiVersion: nv-ipam.nvidia.com/v1alpha1
kind: IPPool
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"nv-ipam.nvidia.com/v1alpha1","kind":"IPPool","metadata":{"annotations":{},"name":"pool1","namespace":"kube-system"},"spec":{"perNodeBlockSize":1,"subnet":"192.168.1.1/31"}}
  creationTimestamp: "2024-10-14T16:44:59Z"
  generation: 17
  name: pool1
  namespace: kube-system
  resourceVersion: "16586"
  uid: b43c059a-9364-4fbc-b945-1a1f017ddb1b
spec:
  perNodeBlockSize: 1
  subnet: 192.168.1.1/31
status:
  allocations:
  - endIP: 192.168.1.1
    nodeName: kind-control-plane
    startIP: 192.168.1.1
  - endIP: 192.168.1.0
    nodeName: kind-worker
    startIP: 192.168.1.0

CIDRPool /32

apiVersion: nv-ipam.nvidia.com/v1alpha1
kind: CIDRPool
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"nv-ipam.nvidia.com/v1alpha1","kind":"CIDRPool","metadata":{"annotations":{},"name":"pool1","namespace":"kube-system"},"spec":{"cidr":"192.168.100.0/24","perNodeNetworkPrefix":32,"staticAllocations":[{"prefix":"192.168.100.0/32"}]}}
  creationTimestamp: "2024-10-14T16:08:21Z"
  generation: 9
  name: pool1
  namespace: kube-system
  resourceVersion: "17155"
  uid: 1a90011c-e373-4ed7-bfd9-8bf1d9935a76
spec:
  cidr: 192.168.100.0/24
  perNodeNetworkPrefix: 32
  staticAllocations:
  - prefix: 192.168.100.0/32
status:
  allocations:
  - nodeName: kind-control-plane
    prefix: 192.168.100.1/32
  - nodeName: kind-worker
    prefix: 192.168.100.2/32
  - nodeName: kind-worker2
    prefix: 192.168.100.3/32
  - nodeName: kind-worker3
    prefix: 192.168.100.4/32

CIDRPool /128

apiVersion: nv-ipam.nvidia.com/v1alpha1
kind: CIDRPool
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"nv-ipam.nvidia.com/v1alpha1","kind":"CIDRPool","metadata":{"annotations":{},"name":"pool1","namespace":"kube-system"},"spec":{"cidr":"fd52:2eb5:44::100/128","perNodeNetworkPrefix":128}}
  creationTimestamp: "2024-10-14T16:08:21Z"
  generation: 11
  name: pool1
  namespace: kube-system
  resourceVersion: "17745"
  uid: 1a90011c-e373-4ed7-bfd9-8bf1d9935a76
spec:
  cidr: fd52:2eb5:44::100/128
  perNodeNetworkPrefix: 128
status:
  allocations:
  - nodeName: kind-control-plane
    prefix: fd52:2eb5:44::100/128

perNodeBlockSize: 1 - useful when you need to deploy one and only one instance of a service per node and you need to make sure that this instance is always have the same predictable IP.

CIDRPool /32 - useful to assign IPs for loopback interfaces on routers

[coveralls]

coverage: 72.493% (+2.0%) from 70.448%
when pulling 07ef882 on ykulazhenkov:pr-single-ip-pools
into f85a716 on Mellanox:main.

[vasrem]

LGTM

A couple of questions and nits

[ykulazhenkov]

@vasrem Thanks for the review! I addressed your comments.