Add Hybrid NAT support (#2261)

* Updates to support hybid NAT * Fix readme * Fix variable order
2024-05-09 15:24:41 +02:00
parent c9503d5ac5
commit c58850c096
9 changed files with 247 additions and 32 deletions
--- a/modules/net-cloudnat/README.md
+++ b/modules/net-cloudnat/README.md
@@ -6,6 +6,7 @@ Simple Cloud NAT management, with optional router creation.
 - [Basic Example](#basic-example)
 - [Subnetwork configuration](#subnetwork-configuration)
 - [Reserved IPs and custom rules](#reserved-ips-and-custom-rules)
+- [Hybrid NAT](#hybrid-nat)
 - [Variables](#variables)
 - [Outputs](#outputs)
 <!-- END TOC -->
@@ -102,6 +103,59 @@ module "nat" {
 }
 # tftest modules=2 resources=5 inventory=rules.yaml e2e
 ```
+## Hybrid NAT
+```hcl
+module "vpc1" {
+  source     = "./fabric/modules/net-vpc"
+  project_id = var.project_id
+  name       = "vpc1"
+  subnets = [
+    {
+      ip_cidr_range = "10.0.0.0/24"
+      name          = "vpc1-subnet"
+      region        = var.region
+    }
+  ]
+  subnets_private_nat = [
+    {
+      ip_cidr_range = "192.168.15.0/24"
+      name          = "vpc1-nat"
+      region        = var.region
+    }
+  ]
+}
+
+module "vpc1-nat" {
+  source         = "./fabric/modules/net-cloudnat"
+  project_id     = var.project_id
+  region         = var.region
+  name           = "vpc1-nat"
+  type           = "PRIVATE"
+  router_network = module.vpc1.id
+  config_source_subnetworks = {
+    all = false
+    subnetworks = [
+      {
+        self_link = module.vpc1.subnet_ids["${var.region}/vpc1-subnet"]
+      }
+    ]
+  }
+  config_port_allocation = {
+    enable_endpoint_independent_mapping = false
+    enable_dynamic_port_allocation      = true
+  }
+  rules = [
+    {
+      description = "private nat"
+      match       = "nexthop.is_hybrid"
+      source_ranges = [
+        module.vpc1.subnets_private_nat["${var.region}/vpc1-nat"].id
+      ]
+    }
+  ]
+}
+# tftest modules=2 resources=7 inventory=hybrid.yaml
+```
 <!-- BEGIN TFDOC -->
 ## Variables

@@ -111,15 +165,16 @@ module "nat" {
 | [project_id](variables.tf#L82) | Project where resources will be created. | <code>string</code> | ✓ |  |
 | [region](variables.tf#L87) | Region where resources will be created. | <code>string</code> | ✓ |  |
 | [addresses](variables.tf#L17) | Optional list of external address self links. | <code>list&#40;string&#41;</code> |  | <code>&#91;&#93;</code> |
-| [config_port_allocation](variables.tf#L23) | Configuration for how to assign ports to virtual machines. min_ports_per_vm and max_ports_per_vm have no effect unless enable_dynamic_port_allocation is set to 'true'. | <code title="object&#40;&#123;&#10;  enable_endpoint_independent_mapping &#61; optional&#40;bool, true&#41;&#10;  enable_dynamic_port_allocation      &#61; optional&#40;bool, false&#41;&#10;  min_ports_per_vm                    &#61; optional&#40;number, 64&#41;&#10;  max_ports_per_vm                    &#61; optional&#40;number, 65536&#41;&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code>&#123;&#125;</code> |
+| [config_port_allocation](variables.tf#L23) | Configuration for how to assign ports to virtual machines. min_ports_per_vm and max_ports_per_vm have no effect unless enable_dynamic_port_allocation is set to 'true'. | <code title="object&#40;&#123;&#10;  enable_endpoint_independent_mapping &#61; optional&#40;bool, true&#41;&#10;  enable_dynamic_port_allocation      &#61; optional&#40;bool, false&#41;&#10;  min_ports_per_vm                    &#61; optional&#40;number&#41;&#10;  max_ports_per_vm                    &#61; optional&#40;number&#41;&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code>&#123;&#125;</code> |
 | [config_source_subnetworks](variables.tf#L39) | Subnetwork configuration. | <code title="object&#40;&#123;&#10;  all                 &#61; optional&#40;bool, true&#41;&#10;  primary_ranges_only &#61; optional&#40;bool&#41;&#10;  subnetworks &#61; optional&#40;list&#40;object&#40;&#123;&#10;    self_link        &#61; string&#10;    all_ranges       &#61; optional&#40;bool, true&#41;&#10;    secondary_ranges &#61; optional&#40;list&#40;string&#41;&#41;&#10;  &#125;&#41;&#41;, &#91;&#93;&#41;&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code>&#123;&#125;</code> |
-| [config_timeouts](variables.tf#L58) | Timeout configurations. | <code title="object&#40;&#123;&#10;  icmp            &#61; optional&#40;number, 30&#41;&#10;  tcp_established &#61; optional&#40;number, 1200&#41;&#10;  tcp_time_wait   &#61; optional&#40;number, 120&#41;&#10;  tcp_transitory  &#61; optional&#40;number, 30&#41;&#10;  udp             &#61; optional&#40;number, 30&#41;&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code>&#123;&#125;</code> |
+| [config_timeouts](variables.tf#L58) | Timeout configurations. | <code title="object&#40;&#123;&#10;  icmp            &#61; optional&#40;number&#41;&#10;  tcp_established &#61; optional&#40;number&#41;&#10;  tcp_time_wait   &#61; optional&#40;number&#41;&#10;  tcp_transitory  &#61; optional&#40;number&#41;&#10;  udp             &#61; optional&#40;number&#41;&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code>&#123;&#125;</code> |
 | [logging_filter](variables.tf#L71) | Enables logging if not null, value is one of 'ERRORS_ONLY', 'TRANSLATIONS_ONLY', 'ALL'. | <code>string</code> |  | <code>null</code> |
 | [router_asn](variables.tf#L92) | Router ASN used for auto-created router. | <code>number</code> |  | <code>null</code> |
 | [router_create](variables.tf#L98) | Create router. | <code>bool</code> |  | <code>true</code> |
 | [router_name](variables.tf#L104) | Router name, leave blank if router will be created to use auto generated name. | <code>string</code> |  | <code>null</code> |
 | [router_network](variables.tf#L110) | Name of the VPC used for auto-created router. | <code>string</code> |  | <code>null</code> |
-| [rules](variables.tf#L116) | List of rules associated with this NAT. | <code title="list&#40;object&#40;&#123;&#10;  description &#61; optional&#40;string&#41;,&#10;  match       &#61; string&#10;  source_ips  &#61; list&#40;string&#41;&#10;&#125;&#41;&#41;">list&#40;object&#40;&#123;&#8230;&#125;&#41;&#41;</code> |  | <code>&#91;&#93;</code> |
+| [rules](variables.tf#L116) | List of rules associated with this NAT. | <code title="list&#40;object&#40;&#123;&#10;  description   &#61; optional&#40;string&#41;&#10;  match         &#61; string&#10;  source_ips    &#61; optional&#40;list&#40;string&#41;&#41;&#10;  source_ranges &#61; optional&#40;list&#40;string&#41;&#41;&#10;&#125;&#41;&#41;">list&#40;object&#40;&#123;&#8230;&#125;&#41;&#41;</code> |  | <code>&#91;&#93;</code> |
+| [type](variables.tf#L136) | Whether this Cloud NAT is used for public or private IP translation. One of 'PUBLIC' or 'PRIVATE'. | <code>string</code> |  | <code>&#34;PUBLIC&#34;</code> |

 ## Outputs

--- a/modules/net-cloudnat/main.tf
+++ b/modules/net-cloudnat/main.tf
@@ -1,5 +1,5 @@
 /**
- * Copyright 2023 Google LLC
+ * Copyright 2024 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
@@ -47,13 +47,21 @@ resource "google_compute_router" "router" {
 }

 resource "google_compute_router_nat" "nat" {
-  project = var.project_id
-  region  = var.region
-  name    = var.name
-  router  = local.router_name
-  nat_ips = var.addresses
+  provider = google-beta
+  project  = var.project_id
+  region   = var.region
+  name     = var.name
+  type     = var.type
+  router   = local.router_name
+  nat_ips  = var.addresses
  nat_ip_allocate_option = (
-    length(var.addresses) > 0 ? "MANUAL_ONLY" : "AUTO_ONLY"
+    var.type == "PRIVATE"
+    ? null
+    : (
+      length(var.addresses) > 0
+      ? "MANUAL_ONLY"
+      : "AUTO_ONLY"
+    )
  )
  source_subnetwork_ip_ranges_to_nat = local.subnet_config
  icmp_idle_timeout_sec              = var.config_timeouts.icmp
@@ -114,7 +122,8 @@ resource "google_compute_router_nat" "nat" {
      description = rules.value.description
      match       = rules.value.match
      action {
-        source_nat_active_ips = rules.value.source_ips
+        source_nat_active_ips    = rules.value.source_ips
+        source_nat_active_ranges = rules.value.source_ranges
      }
    }
  }
--- a/modules/net-cloudnat/variables.tf
+++ b/modules/net-cloudnat/variables.tf
@@ -1,5 +1,5 @@
 /**
- * Copyright 2023 Google LLC
+ * Copyright 2024 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
@@ -25,8 +25,8 @@ variable "config_port_allocation" {
  type = object({
    enable_endpoint_independent_mapping = optional(bool, true)
    enable_dynamic_port_allocation      = optional(bool, false)
-    min_ports_per_vm                    = optional(number, 64)
-    max_ports_per_vm                    = optional(number, 65536)
+    min_ports_per_vm                    = optional(number)
+    max_ports_per_vm                    = optional(number)
  })
  default  = {}
  nullable = false
@@ -58,11 +58,11 @@ output "foo" {
 variable "config_timeouts" {
  description = "Timeout configurations."
  type = object({
-    icmp            = optional(number, 30)
-    tcp_established = optional(number, 1200)
-    tcp_time_wait   = optional(number, 120)
-    tcp_transitory  = optional(number, 30)
-    udp             = optional(number, 30)
+    icmp            = optional(number)
+    tcp_established = optional(number)
+    tcp_time_wait   = optional(number)
+    tcp_transitory  = optional(number)
+    udp             = optional(number)
  })
  default  = {}
  nullable = false
@@ -116,10 +116,30 @@ variable "router_network" {
 variable "rules" {
  description = "List of rules associated with this NAT."
  type = list(object({
-    description = optional(string),
-    match       = string
-    source_ips  = list(string)
+    description   = optional(string)
+    match         = string
+    source_ips    = optional(list(string))
+    source_ranges = optional(list(string))
  }))
  default  = []
  nullable = false
+  validation {
+    condition = alltrue([
+      for r in var.rules :
+      r.source_ips != null || r.source_ranges != null
+    ])
+
+    error_message = "All rules must specify either source_ips or source_ranges."
+  }
+}
+
+variable "type" {
+  description = "Whether this Cloud NAT is used for public or private IP translation. One of 'PUBLIC' or 'PRIVATE'."
+  type        = string
+  default     = "PUBLIC"
+  nullable    = false
+  validation {
+    condition     = var.type == "PUBLIC" || var.type == "PRIVATE"
+    error_message = "Field type must be either PUBLIC or PRIVATE."
+  }
 }