jose-util

JOSE CLI

The jose-util command line utility allows for encryption, decryption, signing and verification of JOSE messages. Its main purpose is to facilitate dealing with JOSE messages when testing or debugging.

Installation

$ go get -u github.com/square/go-jose/jose-util
$ go install github.com/square/go-jose/jose-util

Usage

The utility includes the subcommands encrypt, decrypt, sign, verify and expand. Examples for each command can be found below.

Algorithms are selected via the --alg and --enc flags, which influence the alg and enc headers in respectively. For JWE, --alg specifies the key management algorithm (e.g. RSA-OAEP) and --enc specifies the content encryption algorithm (e.g. A128GCM). For JWS, --alg specifies the signature algorithm (e.g. PS256).

Input and output files can be specified via the --in and --out flags. Either flag can be omitted, in which case jose-util uses stdin/stdout for input/output respectively. By default each command will output a compact message, but it's possible to get the JSON Serialization by supplying the --full flag.

Keys are specified via the --key flag. Supported key types are naked RSA/EC keys and X.509 certificates with embedded RSA/EC keys. Keys must be in PEM, DER or JWK formats.

Testing

cram is used for testing. This can be installed with pip or sudo apt install python-cram See the travis file for how this is used in testing. For example, go build && PATH=$PWD:$PATH cram -v jose-util.t

Examples

Generate key pair

Generates a key pair, either for signing/verification or encryption/decryption. Generated keys will be written to the current directory.

# Generate keys for signing (for RSA-PSS)
jose-util generate-key --use sig --alg RS256

# Generate keys for signing (for EdDSA)
jose-util generate-key --use sig --alg EdDSA

# Generate keys for encryption (for RSA-OAEP)
jose-util generate-key --use enc --alg RSA-OAEP

# Generate keys for encryption (for ECDH-ES)
jose-util generate-key --use enc --alg ECDH-ES+A128KW

Encrypt

Takes a plaintext as input, encrypts, and prints the encrypted message.

# From stdin, to stdout
jose-util encrypt --key public-key.pem --alg RSA-OAEP --enc A128GCM

# Operating on files
jose-util encrypt --key public-key.pem --alg RSA-OAEP --enc A128GCM --in plaintext.txt --out ciphertext.txt

Decrypt

Takes an encrypted message (JWE) as input, decrypts, and prints the plaintext.

# From stdin, to stdout
jose-util decrypt --key private-key.pem

# Operating on files
jose-util decrypt --key private-key.pem --in ciphertext.txt --out plaintext.txt

Sign

Takes a payload as input, signs it, and prints the signed message with the embedded payload.

# From stdin, to stdout
jose-util sign --key private-key.pem --alg PS256

# Operating on files
jose-util sign --key private-key.pem --alg PS256 --in message.txt --out signed-message.txt

Verify

Reads a signed message (JWS), verifies it, and extracts the payload.

# From stdin, to stdout
jose-util verify --key public-key.pem

# Operating on files
jose-util verify --key public-key.pem --in signed-message.txt --out message.txt

Expand

Expands a compact message to the JWE/JWS JSON Serialization format.

jose-util expand --format JWE   # Expands a compact JWE to JWE JSON Serialization
jose-util expand --format JWS   # Expands a compact JWS to JWS JSON Serialization

Decode base64

The JOSE format uses url-safe base64 in payloads, but the base64 utility that ships with most Linux distributions (or macOS) only supports the standard base64 encoding. To make it easier to deal with these payloads a b64decode command is available in jose-util that can decode both regular and url-safe base64 data.

echo "8J-Ukgo" | jose-util b64decode