hcdl: HashiCorp Downloader

hcdl is a tool for easily downloading and installing HashiCorp products.

Installation

hcdl is available for install from crates.io if you have the stable Rust toolchain of at least v1.57.0 installed.

This can be done with the standard Cargo install command:

$ cargo install hcdl

By default, hcdl will embed the HashiCorp GPG key into the binary to facilitate ease of use when installing via Cargo.

The GPG key that will be used can be found in the gpg directory of the source code in the hashicorp.asc file. You may verify this key against the details given at https://www.hashicorp.com/security as detailed below.

If you do not trust the provided GPG key, you can disable the embedding when installing with the following command:

$ cargo install --no-default-features hcdl

Crate Features

hcdl includes two features:

• embed_gpg_key, which embeds the HashiCorp GPG key required to verify the signature of downloaded files
• shell_completion, which adds the --completions CLI argument to generate completions for your chosen shell

Both of these features are enabled by default. If you wished to install hcdl without the embedded GPG key, but with shell completion generation support, you could install as follows:

$ cargo install \
    --no-default-features \
    --features shell_completion \
    hcdl

Usage

hcdl usage is very simple, for example, if we want to download and install the latest version of Terraform, we can run the following:

$ hcdl terraform

You'll see output like the following:

Latest version: terraform v0.15.1 from Mon, 26 Apr 2021 22:02:28 +0000
Downloading and verifying signature of terraform_0.15.1_SHA256SUMS...
Verified against terraform_0.15.1_SHA256SUMS.sig.
Downloading terraform_0.15.1_freebsd_amd64.zip...
  [00:00:04] [########################################] 31.06MB/31.06MB (0s) done.
SHA256 of terraform_0.15.1_freebsd_amd64.zip OK.
Unzipping contents of 'terraform_0.15.1_freebsd_amd64.zip' to '/home/user/.local/bin'
-> Extracting 'terraform' to '/home/user/.local/bin'...
Installation successful.

hcdl has performed the following steps:

• Loaded the HashiCorp GPG key
• Found the latest version of Terraform
• Downloaded the SHA256SUMS GPG signature file
• Downloaded the SHA256SUMS file
• Verified the SHA256SUMS file against the signature
• Downloaded the latest version of Terraform
• Verified that the SHA256 of the downloaded file matches the SHA256SUMS file
• Extracted the terraform binary to a temporary file
• Ensured that the CRC32 of the extracted temporary file matches the record in the zip file
• Installed the terraform binary to ~/.local/bin by moving the temporary file to the appropriate location
• Set the appropriate permissions on the extracted binary

By default, hcdl will download products for the operating system and architecture that it was compiled for (above we were running hcdl on an x86_64 FreeBSD machine), however, you can download any product for any OS and architecture you like by specifying the --os and --arch options.

HashiCorp GPG Key

Due to the GPG signature checking, hcdl needs to know the HashiCorp GPG key. There are two ways to provide the GPG key material:

Compile the HashiCorp GPG Key into the Application

This is the default way in which the GPG key is provided.

hcdl provides the embed_gpg_key feature to compile the GPG key directly into the application. It will use the GPG key provided at gpg/hashicorp.asc in the source repository. You are encouraged to check the validity of this GPG key using the steps below before using this feature.

Once you are happy that the GPG key is valid, you can compile hcdl as follows to enable the GPG key embedding:

$ cargo build --release

Provide hashicorp.asc via the Filesystem

To enable this, place a file named hashicorp.asc containing the HashiCorp GPG key from https://www.hashicorp.com/security into an appropriate directory for your operating system, according to the following table:

To build hcdl with without the embedded GPG key, use the following command:

$ cargo build --release --no-default-features

Verifying the GPG Key

The key you place here should match the key ID and fingerprint shown on the security page, and they can be checked as follows:

$ gpg \
    --dry-run \
    --import \
    --import-options import-show \
    hashicorp.asc

Which should result in the following output:

pub   rsa4096 2021-04-19 [SC] [expires: 2026-04-18]
      C874011F0AB405110D02105534365D9472D7468F
uid                      HashiCorp Security (hashicorp.com/security) <security@hashicorp.com>
sub   rsa4096 2021-04-19 [E] [expires: 2026-04-18]
sub   rsa4096 2021-04-19 [S] [expires: 2022-04-20]
sub   rsa4096 2021-04-21 [S] [expires: 2026-04-20]

gpg: Total number processed: 1

At the time of writing, the GPG key stored within this repository is GPG key ID 72D7468F with fingerprint C874 011F 0AB4 0511 0D02 1055 3436 5D94 72D7 468F, which should match the GPG key published by HashiCorp.

If a GPG key isn't present and you still wish to use the tool, you will be required to explicitly disable the signature verification with the --no-verify-signature flag. Running hcdl by disabling the GPG signature verification is NOT recommended.

Examples

The following examples were gathered on an x86_64 FreeBSD machine.

Checking for the latest Terraform version

$ hcdl --check terraform
Latest version: terraform v0.12.26 from Wed, 27 May 2020 17:17:12 +0000

Retaining Downloaded Zip File after Installation

$ hcdl --keep terraform
Latest version: terraform v0.12.28 from Thu, 25 Jun 2020 16:21:37 +0000
Downloading and verifying signature of terraform_0.12.28_SHA256SUMS...
Verified against terraform_0.12.28_SHA256SUMS.sig.
Downloading terraform_0.12.28_freebsd_amd64.zip...
  [00:00:07] [########################################] 27.07MB/27.07MB (0s) done.
SHA256 of terraform_0.12.28_freebsd_amd64.zip OK.
Unzipping contents of 'terraform_0.12.28_freebsd_amd64.zip' to '/home/user/.local/bin'
-> Extracting 'terraform' to '/home/user/.local/bin'...
Installation successful.
Keeping zipfile terraform_0.12.28_freebsd_amd64.zip in current directory.

Download a Product for a Different OS

$ hcdl --os linux terraform
Latest version: terraform v0.12.28 from Thu, 25 Jun 2020 16:21:37 +0000
Downloading and verifying signature of terraform_0.12.28_SHA256SUMS...
Verified against terraform_0.12.28_SHA256SUMS.sig.
Downloading terraform_0.12.28_linux_amd64.zip...
  [00:00:04] [########################################] 27.11MB/27.11MB (0s) done.
SHA256 of terraform_0.12.28_linux_amd64.zip OK.
Product downloaded for different OS, freebsd != linux
Skipping install and keeping zipfile 'terraform_0.12.28_linux_amd64.zip' in current directory.

Download a Specific Version of a Product

$ hcdl --build 0.12.25 terraform
Downloading and verifying signature of terraform_0.12.25_SHA256SUMS...
Verified against terraform_0.12.25_SHA256SUMS.sig.
Downloading terraform_0.12.25_freebsd_amd64.zip...
  [00:00:03] [########################################] 15.97MB/15.97MB (0s) done.
SHA256 of terraform_0.12.25_freebsd_amd64.zip OK.
Unzipping contents of 'terraform_0.12.25_freebsd_amd64.zip' to '/home/user/.local/bin'
-> Extracting 'terraform' to '/home/user/.local/bin'...
Installation successful.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.