Hashicorp Vault

learn HashiCorp Vault

Notes

  • iam and ec2 auth methods
  • iam uses sts:GetCallerIdentity under the hood
    • vault server receives request with attributes to construct sigv4 and issues the request to AWS STS
    • AWS STS API endpoint is wide open / available to anyone. No auth required to issue request to it.
  • vault roles map/bind to aws roles - vault roles add additional capabilities (e.g. leases, finer grain policies, etc.). new layer to manage

Demo

# install macOS (single golang binary)
brew tap hashicorp/tap
brew install hashicorp/tap/vault


# start in-memory server
vault server -dev

# set env vars
export VAULT_ADDR='http://127.0.0.1:8200'
export VAULT_TOKEN="s.uObLGyypsT6LWnxNaKNurYaV" # ok to expose for demo. ephemeral for in-memoery dev

# confirm connectivity / env vars / server running
vault status

# put secret
vault kv put secret/hello foo=bar

# get secret (json output)
vault kv get -format=json secret/hello

# delete secret
vault kv delete secret/hello

# list secrets engines
vault secrets list -format=json

# enable aws secrets engine
vault secrets enable -path=aws aws

# make aws keys available to env
export AWS_ACCESS_KEY_ID=<aws_access_key_id>
export AWS_SECRET_ACCESS_KEY=<aws_secret_key>

# configure AWS secrets engine
vault write aws/config/root \
    access_key=$AWS_ACCESS_KEY_ID \
    secret_key=$AWS_SECRET_ACCESS_KEY \
    region=us-east-1

# create role
vault write aws/roles/my-role \
        credential_type=iam_user \
        policy_document=-<<EOF
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "Stmt1426528957000",
      "Effect": "Allow",
      "Action": [
        "ec2:*"
      ],
      "Resource": [
        "*"
      ]
    }
  ]
}
EOF

# generate access key pair for role
# creates an IAM user with the policy inlined.
# e.g. arn:aws:iam::529276214230:user/vault-root-my-role-1620146368-5005
vault read aws/creds/my-role



Screenshots

Example IAM User Created by Vault


Resources