iam_loadbalancer_controller.tf

/**
 * Copyright 2020 Quortex
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
*/

locals {
  handle_iam_aws_load_balancer_controller = var.handle_iam_resources && var.handle_iam_aws_load_balancer_controller
}

resource "aws_iam_role" "aws_load_balancer_controller" {
  count       = local.handle_iam_aws_load_balancer_controller ? 1 : 0
  name        = var.aws_load_balancer_controller_role_name
  description = "IAM Role required for aws-load-balancer-controller."

  assume_role_policy = jsonencode({
    Version = "2012-10-17"
    Statement = [
      {
        Effect = "Allow"
        Principal = {
          Federated = "arn:aws:iam::${data.aws_caller_identity.current.account_id}:oidc-provider/${local.cluster_oidc_issuer}"
        }
        Action = "sts:AssumeRoleWithWebIdentity"
        Condition = {
          StringEquals = {
            "${local.cluster_oidc_issuer}:aud" : "sts.amazonaws.com"
            "${local.cluster_oidc_issuer}:sub" : "system:serviceaccount:${var.aws_load_balancer_controller_sa.namespace}:${var.aws_load_balancer_controller_sa.name}"
          }
        }
      }
    ]
  })

  tags = var.tags
}

resource "aws_iam_policy" "aws_load_balancer_controller" {
  count       = local.handle_iam_aws_load_balancer_controller ? 1 : 0
  description = "The policy required for aws-load-balancer-controller."

  policy = jsonencode({
    Version = "2012-10-17",
    Statement = [
      {
        "Effect" : "Allow",
        "Action" : [
          "iam:CreateServiceLinkedRole"
        ],
        "Resource" : "*",
        "Condition" : {
          "StringEquals" : {
            "iam:AWSServiceName" : "elasticloadbalancing.amazonaws.com"
          }
        }
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "ec2:DescribeAccountAttributes",
          "ec2:DescribeAddresses",
          "ec2:DescribeAvailabilityZones",
          "ec2:DescribeInternetGateways",
          "ec2:DescribeVpcs",
          "ec2:DescribeVpcPeeringConnections",
          "ec2:DescribeSubnets",
          "ec2:DescribeSecurityGroups",
          "ec2:DescribeInstances",
          "ec2:DescribeNetworkInterfaces",
          "ec2:DescribeTags",
          "ec2:GetCoipPoolUsage",
          "ec2:DescribeCoipPools",
          "elasticloadbalancing:DescribeLoadBalancers",
          "elasticloadbalancing:DescribeLoadBalancerAttributes",
          "elasticloadbalancing:DescribeListeners",
          "elasticloadbalancing:DescribeListenerCertificates",
          "elasticloadbalancing:DescribeSSLPolicies",
          "elasticloadbalancing:DescribeRules",
          "elasticloadbalancing:DescribeTargetGroups",
          "elasticloadbalancing:DescribeTargetGroupAttributes",
          "elasticloadbalancing:DescribeTargetHealth",
          "elasticloadbalancing:DescribeTags"
        ],
        "Resource" : "*"
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "cognito-idp:DescribeUserPoolClient",
          "acm:ListCertificates",
          "acm:DescribeCertificate",
          "iam:ListServerCertificates",
          "iam:GetServerCertificate",
          "waf-regional:GetWebACL",
          "waf-regional:GetWebACLForResource",
          "waf-regional:AssociateWebACL",
          "waf-regional:DisassociateWebACL",
          "wafv2:GetWebACL",
          "wafv2:GetWebACLForResource",
          "wafv2:AssociateWebACL",
          "wafv2:DisassociateWebACL",
          "shield:GetSubscriptionState",
          "shield:DescribeProtection",
          "shield:CreateProtection",
          "shield:DeleteProtection"
        ],
        "Resource" : "*"
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "ec2:AuthorizeSecurityGroupIngress",
          "ec2:RevokeSecurityGroupIngress"
        ],
        "Resource" : "*"
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "ec2:CreateSecurityGroup"
        ],
        "Resource" : "*"
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "ec2:CreateTags"
        ],
        "Resource" : "arn:aws:ec2:*:*:security-group/*",
        "Condition" : {
          "StringEquals" : {
            "ec2:CreateAction" : "CreateSecurityGroup"
          },
          "Null" : {
            "aws:RequestTag/elbv2.k8s.aws/cluster" : "false"
          }
        }
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "ec2:CreateTags",
          "ec2:DeleteTags"
        ],
        "Resource" : "arn:aws:ec2:*:*:security-group/*",
        "Condition" : {
          "Null" : {
            "aws:RequestTag/elbv2.k8s.aws/cluster" : "true",
            "aws:ResourceTag/elbv2.k8s.aws/cluster" : "false"
          }
        }
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "ec2:AuthorizeSecurityGroupIngress",
          "ec2:RevokeSecurityGroupIngress",
          "ec2:DeleteSecurityGroup"
        ],
        "Resource" : "*",
        "Condition" : {
          "Null" : {
            "aws:ResourceTag/elbv2.k8s.aws/cluster" : "false"
          }
        }
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "elasticloadbalancing:CreateLoadBalancer",
          "elasticloadbalancing:CreateTargetGroup"
        ],
        "Resource" : "*",
        "Condition" : {
          "Null" : {
            "aws:RequestTag/elbv2.k8s.aws/cluster" : "false"
          }
        }
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "elasticloadbalancing:CreateListener",
          "elasticloadbalancing:DeleteListener",
          "elasticloadbalancing:CreateRule",
          "elasticloadbalancing:DeleteRule"
        ],
        "Resource" : "*"
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "elasticloadbalancing:AddTags",
          "elasticloadbalancing:RemoveTags"
        ],
        "Resource" : [
          "arn:aws:elasticloadbalancing:*:*:targetgroup/*/*",
          "arn:aws:elasticloadbalancing:*:*:loadbalancer/net/*/*",
          "arn:aws:elasticloadbalancing:*:*:loadbalancer/app/*/*"
        ],
        "Condition" : {
          "Null" : {
            "aws:RequestTag/elbv2.k8s.aws/cluster" : "true",
            "aws:ResourceTag/elbv2.k8s.aws/cluster" : "false"
          }
        }
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "elasticloadbalancing:AddTags",
          "elasticloadbalancing:RemoveTags"
        ],
        "Resource" : [
          "arn:aws:elasticloadbalancing:*:*:listener/net/*/*/*",
          "arn:aws:elasticloadbalancing:*:*:listener/app/*/*/*",
          "arn:aws:elasticloadbalancing:*:*:listener-rule/net/*/*/*",
          "arn:aws:elasticloadbalancing:*:*:listener-rule/app/*/*/*"
        ]
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "elasticloadbalancing:ModifyLoadBalancerAttributes",
          "elasticloadbalancing:SetIpAddressType",
          "elasticloadbalancing:SetSecurityGroups",
          "elasticloadbalancing:SetSubnets",
          "elasticloadbalancing:DeleteLoadBalancer",
          "elasticloadbalancing:ModifyTargetGroup",
          "elasticloadbalancing:ModifyTargetGroupAttributes",
          "elasticloadbalancing:DeleteTargetGroup"
        ],
        "Resource" : "*",
        "Condition" : {
          "Null" : {
            "aws:ResourceTag/elbv2.k8s.aws/cluster" : "false"
          }
        }
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "elasticloadbalancing:AddTags"
        ],
        "Resource" : [
          "arn:aws:elasticloadbalancing:*:*:targetgroup/*/*",
          "arn:aws:elasticloadbalancing:*:*:loadbalancer/net/*/*",
          "arn:aws:elasticloadbalancing:*:*:loadbalancer/app/*/*"
        ],
        "Condition" : {
          "StringEquals" : {
            "elasticloadbalancing:CreateAction" : [
              "CreateTargetGroup",
              "CreateLoadBalancer"
            ]
          },
          "Null" : {
            "aws:RequestTag/elbv2.k8s.aws/cluster" : "false"
          }
        }
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "elasticloadbalancing:RegisterTargets",
          "elasticloadbalancing:DeregisterTargets"
        ],
        "Resource" : "arn:aws:elasticloadbalancing:*:*:targetgroup/*/*"
      },
      {
        "Effect" : "Allow",
        "Action" : [
          "elasticloadbalancing:SetWebAcl",
          "elasticloadbalancing:ModifyListener",
          "elasticloadbalancing:AddListenerCertificates",
          "elasticloadbalancing:RemoveListenerCertificates",
          "elasticloadbalancing:ModifyRule"
        ],
        "Resource" : "*"
      }
    ]
  })

  tags = var.tags
}

resource "aws_iam_role_policy_attachment" "aws_load_balancer_controller" {
  count      = local.handle_iam_aws_load_balancer_controller ? 1 : 0
  policy_arn = aws_iam_policy.aws_load_balancer_controller[0].arn
  role       = aws_iam_role.aws_load_balancer_controller[0].name
}