Files
ubicloud/prog/kubernetes/provision_kubernetes_node.rb
mohi-kalantari a3c63be15c Disallow access to pods GUA ips from internet
So far pods had both ULA and GUA ipv6 ips and the GUA ip was accessible from
the internet. with this change, we add nft rules to each vm to only allow
connections to be made from inside the pod and disallow all new connections
coming to the GUA ip address.

This change is critical to not expose pods to the internet.
2025-03-31 11:03:41 +02:00

213 lines
7.0 KiB
Ruby

# frozen_string_literal: true
class Prog::Kubernetes::ProvisionKubernetesNode < Prog::Base
subject_is :kubernetes_cluster
def vm
@vm ||= Vm[frame["vm_id"]]
end
def kubernetes_nodepool
@kubernetes_nodepool ||= KubernetesNodepool[frame["nodepool_id"]]
end
def write_hosts_file_if_needed(ip = nil)
return unless Config.development?
return if vm.sshable.cmd("cat /etc/hosts").include?(kubernetes_cluster.endpoint.to_s)
ip ||= kubernetes_cluster.sshable.host
vm.sshable.cmd("sudo tee -a /etc/hosts", stdin: "#{ip} #{kubernetes_cluster.endpoint}\n")
end
def before_run
if kubernetes_cluster.strand.label == "destroy" && strand.label != "destroy"
pop "provisioning canceled"
end
end
label def start
name, vm_size, storage_size_gib = if kubernetes_nodepool
["#{kubernetes_nodepool.ubid}-#{SecureRandom.alphanumeric(5).downcase}",
kubernetes_nodepool.target_node_size,
kubernetes_nodepool.target_node_storage_size_gib]
else
["#{kubernetes_cluster.ubid}-#{SecureRandom.alphanumeric(5).downcase}",
kubernetes_cluster.target_node_size,
kubernetes_cluster.target_node_storage_size_gib]
end
storage_volumes = [{encrypted: true, size_gib: storage_size_gib}] if storage_size_gib
boot_image = "kubernetes-#{kubernetes_cluster.version.tr(".", "_")}"
vm = Prog::Vm::Nexus.assemble_with_sshable(
Config.kubernetes_service_project_id,
sshable_unix_user: "ubi",
name: name,
location_id: kubernetes_cluster.location.id,
size: vm_size,
storage_volumes: storage_volumes,
boot_image: boot_image,
private_subnet_id: kubernetes_cluster.private_subnet_id,
enable_ip4: true
).subject
current_frame = strand.stack.first
current_frame["vm_id"] = vm.id
strand.modified!(:stack)
if kubernetes_nodepool
kubernetes_nodepool.add_vm(vm)
else
kubernetes_cluster.add_cp_vm(vm)
kubernetes_cluster.api_server_lb.add_vm(vm)
end
hop_bootstrap_rhizome
end
label def bootstrap_rhizome
nap 5 unless vm.strand.label == "wait"
vm.sshable.cmd "sudo iptables-nft -t nat -A POSTROUTING -s #{vm.nics.first.private_ipv4} -o ens3 -j MASQUERADE"
vm.sshable.cmd("sudo nft --file -", stdin: <<TEMPLATE)
table ip6 pod_access;
delete table ip6 pod_access;
table ip6 pod_access {
chain ingress_egress_control {
type filter hook forward priority filter; policy drop;
# allow access to the vm itself in order to not break the normal functionality of Clover and SSH
ip6 daddr #{vm.ephemeral_net6.nth(2)} ct state established,related,new counter accept
ip6 saddr #{vm.ephemeral_net6.nth(2)} ct state established,related,new counter accept
# not allow new connections from internet but allow new connections from inside
ip6 daddr #{vm.ephemeral_net6} ct state established,related counter accept
ip6 saddr #{vm.ephemeral_net6} ct state established,related,new counter accept
# used for internal private ipv6 communication between pods
ip6 saddr #{kubernetes_cluster.private_subnet.net6} ct state established,related,new counter accept
ip6 daddr #{kubernetes_cluster.private_subnet.net6} ct state established,related,new counter accept
}
}
TEMPLATE
vm.ephemeral_net6
vm.sshable.cmd "sudo systemctl enable --now kubelet"
bud Prog::BootstrapRhizome, {"target_folder" => "kubernetes", "subject_id" => vm.id, "user" => "ubi"}
hop_wait_bootstrap_rhizome
end
label def wait_bootstrap_rhizome
reap
hop_assign_role if leaf?
donate
end
label def assign_role
write_hosts_file_if_needed
hop_join_worker if kubernetes_nodepool
hop_init_cluster if kubernetes_cluster.cp_vms.count == 1
hop_join_control_plane
end
label def init_cluster
case vm.sshable.cmd("common/bin/daemonizer --check init_kubernetes_cluster")
when "Succeeded"
hop_install_cni
when "NotStarted"
params = {
node_name: vm.name,
cluster_name: kubernetes_cluster.name,
lb_hostname: kubernetes_cluster.endpoint,
port: "443",
private_subnet_cidr4: kubernetes_cluster.private_subnet.net4,
private_subnet_cidr6: kubernetes_cluster.private_subnet.net6,
vm_cidr: vm.nics.first.private_ipv4
}
vm.sshable.cmd("common/bin/daemonizer /home/ubi/kubernetes/bin/init-cluster init_kubernetes_cluster", stdin: JSON.generate(params))
nap 30
when "InProgress"
nap 10
when "Failed"
Clog.emit("INIT CLUSTER FAILED")
nap 65536
# TODO: register deadline
end
nap 65536
end
label def join_control_plane
case vm.sshable.cmd("common/bin/daemonizer --check join_control_plane")
when "Succeeded"
hop_install_cni
when "NotStarted"
cp_sshable = kubernetes_cluster.sshable
params = {
node_name: vm.name,
cluster_endpoint: "#{kubernetes_cluster.endpoint}:443",
join_token: cp_sshable.cmd("sudo kubeadm token create --ttl 24h --usages signing,authentication", log: false).chomp,
certificate_key: cp_sshable.cmd("sudo kubeadm init phase upload-certs --upload-certs", log: false)[/certificate key:\n(.*)/, 1],
discovery_token_ca_cert_hash: cp_sshable.cmd("sudo kubeadm token create --print-join-command", log: false)[/discovery-token-ca-cert-hash (.*)/, 1]
}
vm.sshable.cmd("common/bin/daemonizer kubernetes/bin/join-control-plane-node join_control_plane", stdin: JSON.generate(params), log: false)
nap 15
when "InProgress"
nap 10
when "Failed"
# TODO: Create a page
Clog.emit("JOIN CP NODE TO CLUSTER FAILED")
nap 65536
end
nap 65536
end
label def join_worker
case vm.sshable.cmd("common/bin/daemonizer --check join_worker")
when "Succeeded"
hop_install_cni
when "NotStarted"
cp_sshable = kubernetes_cluster.sshable
params = {
node_name: vm.name,
endpoint: "#{kubernetes_cluster.endpoint}:443",
join_token: cp_sshable.cmd("sudo kubeadm token create --ttl 24h --usages signing,authentication", log: false).tr("\n", ""),
discovery_token_ca_cert_hash: cp_sshable.cmd("sudo kubeadm token create --print-join-command", log: false)[/discovery-token-ca-cert-hash (.*)/, 1]
}
vm.sshable.cmd("common/bin/daemonizer kubernetes/bin/join-worker-node join_worker", stdin: JSON.generate(params), log: false)
nap 15
when "InProgress"
nap 10
when "Failed"
# TODO: Create a page
Clog.emit("JOIN WORKER NODE TO CLUSTER FAILED")
nap 65536
end
nap 65536
end
label def install_cni
cni_config = <<CONFIG
{
"cniVersion": "1.0.0",
"name": "ubicni-network",
"type": "ubicni",
"ranges":{
"subnet_ipv6": "#{NetAddr::IPv6Net.new(vm.ephemeral_net6.network, NetAddr::Mask128.new(80))}",
"subnet_ula_ipv6": "#{vm.nics.first.private_ipv6}",
"subnet_ipv4": "#{vm.nics.first.private_ipv4}"
}
}
CONFIG
vm.sshable.cmd("sudo tee /etc/cni/net.d/ubicni-config.json", stdin: cni_config)
pop vm_id: vm.id
end
end