GitHub - schollz/croc: Easily and securely send things from one computer to another :package:

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About croc is a tool that allows any two computers to simply and securely transfer files and folders. AFAIK, croc is the only CLI file-transfer tool that does all of the following:

Allows any two computers to transfer data (using a relay) Provides end-to-end encryption (using PAKE) Enables easy cross-platform transfers (Windows, Linux, Mac) Allows multiple file transfers Allows resuming transfers that are interrupted No need for local server or port-forwarding IPv6-first with IPv4 fallback Can use a proxy, like Tor

For more information about croc, see my blog post or read a recent interview I did.

Install You can download the latest release for your system, or install a release from the command-line: curl https://getcroc.schollz.com | bash On macOS Using Homebrew: brew install croc Using MacPorts: sudo port selfupdate sudo port install croc On Windows You can install the latest release with Scoop, Chocolatey, or Winget: scoop install croc choco install croc winget install schollz.croc Using nix-env You can install the latest release with Nix: nix-env -i croc On NixOS You can add this to your configuration.nix: environment.systemPackages = [ pkgs.croc ]; On Alpine Linux First, install dependencies: apk add bash coreutils wget -qO- https://getcroc.schollz.com | bash On Arch Linux Install with pacman: pacman -S croc On Fedora Install with dnf: dnf install croc On Gentoo Install with portage: emerge net-misc/croc On Termux Install with pkg: pkg install croc On FreeBSD Install with pkg: pkg install croc On Linux, macOS, and Windows via Conda You can install from conda-forge globally with pixi: pixi global install croc Or install into a particular environment with conda: conda install --channel conda-forge croc On Linux, macOS via

Docker Add the following one-liner function to your ~/.profile (works with any POSIX-compliant shell): croc() { [ $# -eq 0 ] && set -- ""; mkdir -p "$HOME/.config/croc"; docker run --rm -it --user "$(id -u):$(id -g)" -v "$(pwd):/c" -v "$HOME/.config/croc:/.config/croc" -w /c -e CROC_SECRET docker.io/schollz/croc "$@"; } You can also just paste it in the terminal for current session. On first run Docker will pull the image. croc via Docker will only work within the current directory and its subdirectories. Build from Source If you prefer, you can install Go and build from source (requires Go 1.22+): go install github.com/schollz/croc/v10@latest On Android There is a 3rd-party F-Droid app available to download. Usage To send a file, simply do: $ croc send [file(s)-or-folder] Sending 'file-or-folder' (X MB) Code is: code-phrase Then, to receive the file (or folder) on another computer, run: croc code-phrase The code phrase is used to establish password-authenticated key agreement (PAKE) which generates a secret key for the sender and recipient to use for end-to-end encryption. Customizations & Options Using croc on Linux or macOS On Linux and macOS, the sending and receiving process is slightly different to avoid leaking the secret via the process name. You will need to run croc with the secret as an environment variable. For example, to receive with the secret ***: CROC_SECRET=*** croc For single-user systems, the default behavior can be permanently enabled by running: croc --classic Custom Code Phrase You can send with your own code phrase (must be at least 6 characters): croc send --code [code-phrase] [file(s)-or-folder] Allow Overwriting Without Prompt To automatically overwrite

files without prompting, use the --overwrite flag: croc --yes --overwrite <code> Excluding Folders To exclude folders from being sent, use the --exclude flag with comma-delimited exclusions: croc send --exclude "node_modules,.venv" [folder] Use Pipes - stdin and stdout You can pipe to croc: cat [filename] | croc send To receive the file to stdout, you can use: croc --yes [code-phrase] > out Send Text To send URLs or short text, use: croc send --text "hello world" Send Multiple Files You can send multiple files directly by listing the files and/or folders: croc send [file1] [file2] [file3] [folder1] [folder2] Show QR Code To show QR code (for mobile devices), use: croc send --qr [file(s)-or-folder] Use a Proxy You can send files via a proxy by adding --socks5: croc --socks5 "127.0.0.1:9050" send SOMEFILE Change Encryption Curve To choose a different elliptic curve for encryption, use the --curve flag: croc --curve p521 <codephrase> Change Hash Algorithm For faster hashing, use the imohash algorithm: croc send --hash imohash SOMEFILE Clipboard Options By default, the code phrase is copied to your clipboard. To disable this: croc --disable-clipboard send [filename] To copy the full command with the secret as an environment variable (useful on Linux/macOS): croc --extended-clipboard send [filename] This copies the full command like CROC_SECRET="code-phrase" croc (including any relay/pass flags). Quiet Mode To suppress all output (useful for scripts and automation): croc --quiet send [filename] Self-host Relay You can run your own relay: croc relay By default, it uses TCP ports 9009-9013. You can customize the ports (e.g., croc relay --ports 1111,1112), but at least 2 ports are required.

To send files using your relay: croc --relay "myrelay.example.com:9009" send [filename] Self-host Relay with Docker You can also run a relay with Docker: docker run -d -p 9009-9013:9009-9013 -e CROC_PASS='YOURPASSWORD' docker.io/schollz/croc To send files using your custom relay: croc --pass YOURPASSWORD --relay "myreal.example.com:9009" send [filename] To use custom ports, set CROC_PORTS (comma-separated) or CROC_PORT (base port): docker run -d -p 9010-9011:9010-9011 -e CROC_PORTS='9010,9011' -e CROC_PASS='YOURPASSWORD' docker.io/schollz/croc Acknowledgements croc has evolved through many iterations, and I am thankful for the contributions! Special thanks to:

@warner for the idea @tscholl2 for the encryption gists @skorokithakis for proxying two connections

And many more!