How to generate custom keys when configuring Bitbucket Server VCS provider in HCP Terraform and Terraform Enterprise

Prerequisites

• Terraform Cloud and Enterprise
• Bitbucket Datacenter and Server
• Terminal with access to openssl and ssh-keygen commands

Use Case

• Generate a consumer and PEM key pair to setup the VCS provider connection to Bitbucket Datacenter and Server. This applies to Step 1 item 5 of the official documentation

Procedure

• Toggle Use Custom Keys, it will display three empty fields for: Consumer key, Public key and Private key
• Open the terminal and generate a consumer key and paste it in HCP/TFE
  

  ❯ openssl rand -base64 32|pbcopy
  QO2TjuZ6FzbWMqJcA6uR757NJOi65be1yZBqgl0A9aw=

• Generate a custom SSH key first (adjust the path and key name appropriately). Only hit enter when prompted for a passphrase. 

  ❯ ssh-keygen -t rsa -m PEM -f "/Users/jsorondo/.ssh/custom_terraform" -C "custom_terraform_enterprise"
  Generating public/private rsa key pair.
  Enter passphrase (empty for no passphrase):
  Enter same passphrase again:
  Your identification has been saved in /Users/jsorondo/.ssh/custom_terraform
  Your public key has been saved in /Users/jsorondo/.ssh/custom_terraform.pub
  The key fingerprint is:
  SHA256:qC5yFJJ42HJuGqJSML+fUDIu3/Ze+ZIEz/hLEJEy86k custom_terraform_enterprise
  The key's randomart image is:
  +---[RSA 3072]----+
  | .. |
  | + .. |
  |.+ =.. |
  |O = +o |
  | Xo...o=S |
  |o.*+E...+. |
  |+*o.. o+. |
  |=o++.. o+. |
  |.o.+=oo .o. |
  +----[SHA256]-----+

• Using openssl retrieve the public key in PEM format, copy to the clipboard and paste it in the Public key field.
  

  ❯ openssl rsa -in ~/.ssh/custom_terraform -outform PEM -pubout -out ~/.ssh/pubkey.pem
  writing RSA key
  ❯ cat ~/.ssh/pubkey.pem|pbcopy

• Copy the private key to the clipboard and paste it in the Private key field
  

  cat ~/.ssh/custom_terraform|pbcopy

• Continue from Step 2 of the official documentation to complete the setup