🔀 Move @soulshake's scripts and commands to prepare-eks directory

2026-02-14 09:39:56 +00:00 · 2021-03-28 12:59:54 +02:00
parent b23aacdce0
commit b9ea938157
3 changed files with 89 additions and 133 deletions
--- a/bin/sa-can-read-s3.sh
+++ b/bin/sa-can-read-s3.sh
@@ -1,133 +0,0 @@
-#!/usr/bin/env bash
-# I would like to demonstrate access to AWS resource (e.g. S3 bucket) from a pod. Idea:
-# create a bucket, put two objects in it (one public, one private), then … I suppose I
-# need to create a role with access to the private object, associate the role to a service
-# account in k8s, find an image with the aws CLI (or some s3 client) in it … ?
-
-set -euo pipefail
-
-emit_describe_cluster_policy() {
-    # Not used right now, but this permission is required in order to run `aws eks update-kubeconfig`:
-    echo '{
-    "Version": "2012-10-17",
-    "Statement": [
-        {
-            "Action": [
-                "eks:DescribeCluster"
-            ],
-            "Resource": "'"arn:aws:eks:${REGION}:${ACCOUNT_ID}:cluster/${CLUSTER_NAME}"'",
-            "Effect": "Allow"
-        }
-    ]
-}'
-}
-
-create_describe_cluster_policy() {
-    aws iam create-policy \
-        --policy-name ${DESCRIBE_CLUSTER_POLICY_NAME} \
-        --description "Policy allowing to describe ${CLUSTER_NAME}" \
-        --policy-document "$(emit_describe_cluster_policy)"
-
-    # to attach:
-    # aws iam attach-user-policy --user-name "${user_name}" --policy-arn "arn:aws:iam::${ACCOUNT_ID}:policy/${DESCRIBE_CLUSTER_POLICY_NAME}"
-}
-
-emit_service_account_role_trust_policy() {
-    local oidc_provider_arn key_prefix
-    oidc_provider_arn="$(aws iam list-open-id-connect-providers | jq -r '.OpenIDConnectProviderList[0].Arn')"
-    key_prefix="$(echo "${oidc_provider_arn}" | cut -f2- -d '/')"
-
-    echo '{
-  "Version": "2012-10-17",
-  "Statement": [
-    {
-      "Effect": "Allow",
-      "Principal": {
-        "Federated": "'"${oidc_provider_arn}"'"
-      },
-      "Action": "sts:AssumeRoleWithWebIdentity",
-      "Condition": {
-        "StringEquals": {
-            "'"${key_prefix}:sub"'": "system:serviceaccount:default:default"
-        }
-      }
-    }
-  ]
-}'
-}
-
-associate_oidc_provider() {
-    local issuer_url
-    issuer_url="$(aws eks describe-cluster --name "${CLUSTER_NAME}" --query "cluster.identity.oidc.issuer" --output text)"
-    if ! aws iam list-open-id-connect-providers | grep "${issuer_url}"; then
-        eksctl utils associate-iam-oidc-provider --cluster "${CLUSTER_NAME}" --approve
-    else
-        echo "OIDC provider already associated"
-    fi
-}
-
-create_role() {
-    if ! _="$(aws iam get-role --role-name "${ROLE_NAME}")"; then
-        aws iam create-role --role-name "${ROLE_NAME}" --description "Role for service account" --assume-role-policy-document "$(emit_service_account_role_trust_policy)"
-    else
-        echo "Role ${ROLE_NAME} already exists"
-    fi
-}
-
-annotate_serviceaccount() {
-    kubectl annotate serviceaccounts default -n default "role-arn=arn:aws:iam::${ACCOUNT_ID}:role/${ROLE_NAME}" --overwrite
-}
-
-checkit() {
-    echo "Will try to read s3://"${BUCKET_NAME}"/top-sekret.txt"
-    kubectl run --image amazon/aws-cli --attach --restart=Never --rm --wait=true can-we-read-s3 -- s3 cp s3://"${BUCKET_NAME}"/top-sekret.txt -
-}
-
-update_kubeconfig() {
-    aws eks update-kubeconfig --name "${CLUSTER_NAME}"
-}
-
-teardown() {
-    # see also 'can-describe-cluster' policy, if created via create_describe_cluster_policy
-    aws iam detach-role-policy --policy-arn "${S3_POLICY_ARN}" --role-name "${ROLE_NAME}"
-    aws iam delete-role "${ROLE_NAME}"
-    # for username in users; do ...
-    # aws iam detach-user-policy --policy-arn "arn:aws:iam::${ACCOUNT_ID}:policy/${DESCRIBE_CLUSTER_POLICY_NAME}" --user-name "${username}"
-    aws iam delete-policy --policy-arn "arn:aws:iam::${ACCOUNT_ID}:policy/${DESCRIBE_CLUSTER_POLICY_NAME}"
-}
-
-create_and_populate_bucket() {
-    if ! _="$(aws s3api get-bucket-acl --bucket "${BUCKET_NAME}")"; then
-        aws s3api create-bucket --region "${REGION}" --bucket "${BUCKET_NAME}" --create-bucket-configuration "LocationConstraint=${REGION}"
-    else
-        echo "Bucket ${BUCKET_NAME} already exists."
-    fi
-    f="$(mktemp)"
-    echo "THE UNICORN IS IN THE GARDEN!!" >"${f}"
-    aws s3api put-object --bucket "${BUCKET_NAME}" --key top-sekret.txt --body "${f}"
-}
-
-ACCOUNT_ID="$(aws sts get-caller-identity | jq -r .Account)"
-S3_POLICY_ARN=arn:aws:iam::aws:policy/AmazonS3ReadOnlyAccess
-CLUSTER_NAME=floral-mongoose-1616851817
-DESCRIBE_CLUSTER_POLICY_NAME=can-describe-cluster
-ROLE_NAME=service-account-role
-REGION=eu-north-1
-BUCKET_NAME=wooga-booga-pants
-export KUBECONFIG=myconfig
-
-main() {
-    if [ -n "${1:-}" ]; then
-        echo "An argument was provided, running that: $1"
-        "${1}"
-    else
-        echo "ACCOUNT_ID: $ACCOUNT_ID"
-        associate_oidc_provider
-        create_role
-        aws iam attach-role-policy --role-name "${ROLE_NAME}" --policy-arn "${S3_POLICY_ARN}"
-        annotate_serviceaccount
-        checkit
-    fi
-}
-
-main "$@"
--- a/prepare-eks/70_oidc.sh
+++ b/prepare-eks/70_oidc.sh
@@ -0,0 +1,46 @@
+#!/bin/sh
+
+# Note: if cluster was created without OIDC provider attached,
+# you need to run the following command. It is idempotent.
+#eksctl utils associate-iam-oidc-provider --cluster cluster-name-12341234 --approve
+
+if [ "$1" ]; then
+    CLUSTER="$1"
+else
+    echo "Please indicate cluster to use. Available clusters:"
+    aws eks list-clusters --output table
+    exit 1
+fi
+
+ACCOUNT=$(aws sts get-caller-identity | jq -r .Account)
+OIDC=$(aws eks describe-cluster --name $CLUSTER --query cluster.identity.oidc.issuer --output text | cut -d/ -f3-)
+ROLE_NAME=s3-reader-container-training
+TRUST_POLICY=$(envsubst <<EOF
+{
+  "Version": "2012-10-17",
+  "Statement": [
+    {
+      "Effect": "Allow",
+      "Principal": {
+        "Federated": "arn:aws:iam::${ACCOUNT}:oidc-provider/${OIDC}"
+      },
+      "Action": "sts:AssumeRoleWithWebIdentity",
+      "Condition": {
+        "StringLike": {
+            "${OIDC}:sub": ["system:serviceaccount:container-training:*"]
+        }
+      }
+    }
+  ]
+}
+EOF
+)
+
+aws iam create-role \
+    --role-name "$ROLE_NAME" \
+    --assume-role-policy-document "$TRUST_POLICY"
+
+kubectl annotate serviceaccounts \
+    --namespace container-training default \
+    "eks.amazonaws.com/role-arn=arn:aws:iam::$ACCOUNT:role/$ROLE_NAME" \
+    --overwrite
--- a/prepare-eks/80_s3_bucket.sh
+++ b/prepare-eks/80_s3_bucket.sh
@@ -0,0 +1,43 @@
+#!/bin/sh
+
+ACCOUNT=$(aws sts get-caller-identity | jq -r .Account)
+BUCKET=container.training
+ROLE_NAME=s3-reader-container-training
+POLICY_NAME=s3-reader-container-training
+POLICY_DOC=$(envsubst <<EOF
+{
+  "Version": "2012-10-17",
+  "Statement": [
+    {
+      "Effect": "Allow",
+      "Action": [
+        "s3:ListBucket",
+        "s3:GetObject*"
+      ],
+      "Resource": [
+        "arn:aws:s3:::$BUCKET",
+        "arn:aws:s3:::$BUCKET/*"
+      ]
+    }
+  ]
+}
+EOF
+)
+
+aws iam create-policy \
+--policy-name $POLICY_NAME \
+--policy-doc "$POLICY_DOC"
+
+aws s3 mb s3://container.training
+
+echo "this is a public object" \
+| aws s3 cp - s3://container.training/public.txt \
+--acl public-read
+
+echo "this is a private object" \
+| aws s3 cp - s3://container.training/private.txt \
+--acl private
+
+aws iam attach-role-policy \
+    --role-name "$ROLE_NAME" \
+    --policy-arn arn:aws:iam::$ACCOUNT:policy/$POLICY_NAME