certsponge

Utility for splitting Vault's PKI output into one or more files containing the private key, certificate, and CA data.

Creates tls.pem and ca.crt:

vault write pki -format=json pki/issue/rolename common_name=web.dom.tld | certsponge

Override default behavior with flags. certsponge -h for usage:

vault write -format=json pki/issue/rolename common_name=web.dom.tld \
  | certsponge \
    -bundle "" \
    -key tls.key \
    -cert tls.crt \
    -ca-cert ca.crt

Install

• Install latest using go install: go install github.com/joemiller/certsponge@latest

• macOS Homebrew/Linuxbrew: brew install joemiller/taps/certsponge

• Pre-built binaries and packages are available for various platforms on the GitHub Releases page.

• Docker images are available on ghcr.io.

Usage

certsponge expects to receive the JSON output from vault write pki/issue/...:

vault write pki -format=json pki/issue/rolename common_name=web.dom.tld | certsponge

By default the output is saved into two files in the current directory:

• tls.pem: Contains private_key, certificate, and ca_chain (in that order).
• ca.crt: Contains ca_chain.

This behavior can be changed via flags. Run with -h for usage.

Files containing private_key are always created with mode 0600.

Files containing only non-sensitive data (certificate and ca_chain) are created with mode 0644.

Existing files will not be overwritten unless -f flag is specified.

Motivation

I got tired of writing blocks like this (and many other variations) in scripts:

out=$(vault write -format=json pki/issue/myrole common_name=foo)
key=$(jq -r '.data.private_key' <<<"$out")
cert=$(jq -r '.data.certificate' <<<"$out")
ca=$(jq -r '.data.ca_chain' <<<"$out")
{
  echo "$key"
  echo "$cert"
  echo "$ca"
} >tls.pem

Similar Tools

• vaultbot is an excellent tool that implements the full end-to-end process of requesting certs from Vault and writing them to files. It also handles renewals. certsponge is not trying to do all of that, it's only goal is split the output from the vault CLI into files.