General information on Goauld

Quick start

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This setup involves three components running on separate machines:

Server: publicly reachable machine
Client (tealc): operator machine
Agent: target machine

Prebuilt client and server binaries are available at https://github.com/Hazegard/Goauld/releases.

See general/compilation to compile the components.

Generate secrets

Install age, then run:

$ age-keygen
# created: 2026-03-27T21:44:18+01:00
# public key: age1krjxdnhmf2kqm8rdhyf6sr5nfvlwdcslux3fxt8amcrncwn3ss9sydlvd0
AGE-SECRET-KEY-1NJ4DRPNKNGEVFK50JHUD6RKZ3NJ3Q9S5KYMTARTLXU0P0KQU8AAQNE4C2F

The private key (AGE-SECRET-KEY-*) is used by the server, and the public key is embedded in agents.

Generate access token (and admin token)

openssl rand -base64 42

At this point, you should have:

Compilation

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Some components require specific Go build tags:

client: -tags client
mini_agent: -tags mini

The project can also be built using GoReleaser.

Optional build dependencies

garble for binary obfuscation (https://github.com/burrowers/garble)
upx for binary compression https://github.com/upx/upx
goreleaser for automated builds https://github.com/goreleaser/goreleaser

Agent

Direct compilation

go build -o tealc ./agent

Using the wrapper script

go run ./scripts/build/ --id agent --goos windows --goarch amd64 --no-seed --gen-age-key=false --gen-access-token=false

Using the client CLI

tealc compile --id agent --goarch amd64 --goos windows

Note

Compiling with the CLI is recommended as it allows passing compile-time variables to the agent (see [How to feed variables])

Variables

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Passing variables to components (agent, client & server)

Components can retrieve configuration parameters from several sources. The following order defines the precedence (from highest to lowest):

Command-line argument (--var=1)
Configuration file passed through command line (--config)
Environment variable (e.g. VAR=1)
Default configuration file (see general/configuration file)
Compile-time defined value (-ldflags, or compiling with tealc compile --env: general/compilation)
Hardcoded default value

Configuration file

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The server, agent, and client share the same behavior when loading configuration files.

Each component looks for a configuration file in the $HOME/.config directory, then in the current directory.

The configuration filenames for each component are:

Server	Agent	Client
`goauld_server.yaml`	`goauld_agent.yaml` / `goauld.yaml`	`tealc.yaml`

Architecture

Mon, 01 Jan 0001 00:00:00 +0000