jose

README

Go JOSE

Package jose aims to provide an implementation of the Javascript Object Signing and Encryption set of standards. This includes support for JSON Web Encryption, JSON Web Signature, and JSON Web Token standards.

Disclaimer: This library contains encryption software that is subject to the U.S. Export Administration Regulations. You may not export, re-export, transfer or download this code or any part of it in violation of any United States law, directive or regulation. In particular this software may not be exported or re-exported in any form or on any media to Iran, North Sudan, Syria, Cuba, or North Korea, or to denied persons or entities mentioned on any US maintained blocked list.

Overview

The implementation follows the JSON Web Encryption (RFC 7516), JSON Web Signature (RFC 7515), and JSON Web Token (RFC 7519). Tables of supported algorithms are shown below. The library supports both the compact and full serialization formats, and has optional support for multiple recipients. It also comes with a small command-line utility (jose-util) for dealing with JOSE messages in a shell.

Note: We use a forked version of the encoding/json package from the Go standard library which uses case-sensitive matching for member names (instead of case-insensitive matching). This is to avoid differences in interpretation of messages between go-jose and libraries in other languages.

Versions

We use gopkg.in for versioning.

Version 2 (branch, doc) is the current version:

import "gopkg.in/square/go-jose.v2"

The old v1 branch (go-jose.v1) will still receive backported bug fixes and security fixes, but otherwise development is frozen. All new feature development takes place on the v2 branch. Version 2 also contains additional sub-packages such as the jwt implementation contributed by @shaxbee.

Supported algorithms

See below for a table of supported algorithms. Algorithm identifiers match the names in the JSON Web Algorithms standard where possible. The Godoc reference has a list of constants.

Key encryption	Algorithm identifier(s)
RSA-PKCS#1v1.5	RSA1_5
RSA-OAEP	RSA-OAEP, RSA-OAEP-256
AES key wrap	A128KW, A192KW, A256KW
AES-GCM key wrap	A128GCMKW, A192GCMKW, A256GCMKW
ECDH-ES + AES key wrap	ECDH-ES+A128KW, ECDH-ES+A192KW, ECDH-ES+A256KW
ECDH-ES (direct)	ECDH-ES1
Direct encryption	dir1

^{1. Not supported in multi-recipient mode}

Signing / MAC	Algorithm identifier(s)
RSASSA-PKCS#1v1.5	RS256, RS384, RS512
RSASSA-PSS	PS256, PS384, PS512
HMAC	HS256, HS384, HS512
ECDSA	ES256, ES384, ES512
Ed25519	EdDSA2

^{2. Only available in version 2 of the package}

Content encryption	Algorithm identifier(s)
AES-CBC+HMAC	A128CBC-HS256, A192CBC-HS384, A256CBC-HS512
AES-GCM	A128GCM, A192GCM, A256GCM

Compression	Algorithm identifiers(s)
DEFLATE (RFC 1951)	DEF

Supported key types

See below for a table of supported key types. These are understood by the library, and can be passed to corresponding functions such as NewEncrypter or NewSigner. Each of these keys can also be wrapped in a JWK if desired, which allows attaching a key id.

Algorithm(s)	Corresponding types
RSA	*rsa.PublicKey, *rsa.PrivateKey
ECDH, ECDSA	*ecdsa.PublicKey, *ecdsa.PrivateKey
EdDSA1	ed25519.PublicKey, ed25519.PrivateKey
AES, HMAC	[]byte

^{1. Only available in version 2 of the package}

Examples

Examples can be found in the Godoc reference for this package. The jose-util subdirectory also contains a small command-line utility which might be useful as an example.

Documentation

Overview

Package jose aims to provide an implementation of the Javascript Object Signing and Encryption set of standards. It implements encryption and signing based on the JSON Web Encryption and JSON Web Signature standards, with optional JSON Web Token support available in a sub-package. The library supports both the compact and full serialization formats, and has optional support for multiple recipients.

Example (JWE)

// Generate a public/private key pair to use for this example.
privateKey, err := rsa.GenerateKey(rand.Reader, 2048)
if err != nil {
	panic(err)
}

// Instantiate an encrypter using RSA-OAEP with AES128-GCM. An error would
// indicate that the selected algorithm(s) are not currently supported.
publicKey := &privateKey.PublicKey
encrypter, err := NewEncrypter(A128GCM, Recipient{Algorithm: RSA_OAEP, Key: publicKey}, nil)
if err != nil {
	panic(err)
}

// Encrypt a sample plaintext. Calling the encrypter returns an encrypted
// JWE object, which can then be serialized for output afterwards. An error
// would indicate a problem in an underlying cryptographic primitive.
var plaintext = []byte("Lorem ipsum dolor sit amet")
object, err := encrypter.Encrypt(plaintext)
if err != nil {
	panic(err)
}

// Serialize the encrypted object using the full serialization format.
// Alternatively you can also use the compact format here by calling
// object.CompactSerialize() instead.
serialized := object.FullSerialize()

// Parse the serialized, encrypted JWE object. An error would indicate that
// the given input did not represent a valid message.
object, err = ParseEncrypted(serialized)
if err != nil {
	panic(err)
}

// Now we can decrypt and get back our original plaintext. An error here
// would indicate the the message failed to decrypt, e.g. because the auth
// tag was broken or the message was tampered with.
decrypted, err := object.Decrypt(privateKey)
if err != nil {
	panic(err)
}

fmt.Printf(string(decrypted))

Output:

Lorem ipsum dolor sit amet

Example (JWS)

// Generate a public/private key pair to use for this example.
privateKey, err := rsa.GenerateKey(rand.Reader, 2048)
if err != nil {
	panic(err)
}

// Instantiate a signer using RSASSA-PSS (SHA512) with the given private key.
signer, err := NewSigner(SigningKey{Algorithm: PS512, Key: privateKey}, nil)
if err != nil {
	panic(err)
}

// Sign a sample payload. Calling the signer returns a protected JWS object,
// which can then be serialized for output afterwards. An error would
// indicate a problem in an underlying cryptographic primitive.
var payload = []byte("Lorem ipsum dolor sit amet")
object, err := signer.Sign(payload)
if err != nil {
	panic(err)
}

// Serialize the encrypted object using the full serialization format.
// Alternatively you can also use the compact format here by calling
// object.CompactSerialize() instead.
serialized := object.FullSerialize()

// Parse the serialized, protected JWS object. An error would indicate that
// the given input did not represent a valid message.
object, err = ParseSigned(serialized)
if err != nil {
	panic(err)
}

// Now we can verify the signature on the payload. An error here would
// indicate the the message failed to verify, e.g. because the signature was
// broken or the message was tampered with.
output, err := object.Verify(&privateKey.PublicKey)
if err != nil {
	panic(err)
}

fmt.Printf(string(output))

Output:

Lorem ipsum dolor sit amet

Index

• Constants
• Variables
• type CompressionAlgorithm
• type ContentEncryption
• type ContentType
• type Encrypter
  • func NewEncrypter(enc ContentEncryption, rcpt Recipient, opts *EncrypterOptions) (Encrypter, error)
  • func NewMultiEncrypter(enc ContentEncryption, rcpts []Recipient, opts *EncrypterOptions) (Encrypter, error)
• type EncrypterOptions
  • func (eo *EncrypterOptions) WithContentType(contentType ContentType) *EncrypterOptions
  • func (eo *EncrypterOptions) WithHeader(k HeaderKey, v interface{}) *EncrypterOptions
  • func (eo *EncrypterOptions) WithType(typ ContentType) *EncrypterOptions
• type Header
  • func (h Header) Certificates(opts x509.VerifyOptions) ([][]*x509.Certificate, error)
• type HeaderKey
• type JSONWebEncryption
  • func ParseEncrypted(input string) (*JSONWebEncryption, error)
  • func (obj JSONWebEncryption) CompactSerialize() (string, error)
  • func (obj JSONWebEncryption) Decrypt(decryptionKey interface{}) ([]byte, error)
  • func (obj JSONWebEncryption) DecryptMulti(decryptionKey interface{}) (int, Header, []byte, error)
  • func (obj JSONWebEncryption) FullSerialize() string
  • func (obj JSONWebEncryption) GetAuthData() []byte
• type JSONWebKey
  • func (k *JSONWebKey) IsPublic() bool
  • func (k JSONWebKey) MarshalJSON() ([]byte, error)
  • func (k *JSONWebKey) Public() JSONWebKey
  • func (k *JSONWebKey) Thumbprint(hash crypto.Hash) ([]byte, error)
  • func (k *JSONWebKey) UnmarshalJSON(data []byte) (err error)
  • func (k *JSONWebKey) Valid() bool
• type JSONWebKeySet
  • func (s *JSONWebKeySet) Key(kid string) []JSONWebKey
• type JSONWebSignature
  • func ParseDetached(signature string, payload []byte) (*JSONWebSignature, error)
  • func ParseSigned(signature string) (*JSONWebSignature, error)
  • func (obj JSONWebSignature) CompactSerialize() (string, error)
  • func (obj JSONWebSignature) DetachedCompactSerialize() (string, error)
  • func (obj JSONWebSignature) DetachedVerify(payload []byte, verificationKey interface{}) error
  • func (obj JSONWebSignature) DetachedVerifyMulti(payload []byte, verificationKey interface{}) (int, Signature, error)
  • func (obj JSONWebSignature) FullSerialize() string
  • func (obj JSONWebSignature) UnsafePayloadWithoutVerification() []byte
  • func (obj JSONWebSignature) Verify(verificationKey interface{}) ([]byte, error)
  • func (obj JSONWebSignature) VerifyMulti(verificationKey interface{}) (int, Signature, []byte, error)
• type KeyAlgorithm
• type NonceSource
• type OpaqueKeyDecrypter
• type OpaqueKeyEncrypter
• type OpaqueSigner
• type OpaqueVerifier
• type Recipient
• type Signature
• type SignatureAlgorithm
• type Signer
  • func NewMultiSigner(sigs []SigningKey, opts *SignerOptions) (Signer, error)
  • func NewSigner(sig SigningKey, opts *SignerOptions) (Signer, error)
• type SignerOptions
  • func (so *SignerOptions) WithBase64(b64 bool) *SignerOptions
  • func (so *SignerOptions) WithContentType(contentType ContentType) *SignerOptions
  • func (so *SignerOptions) WithCritical(names ...string) *SignerOptions
  • func (so *SignerOptions) WithHeader(k HeaderKey, v interface{}) *SignerOptions
  • func (so *SignerOptions) WithType(typ ContentType) *SignerOptions
• type SigningKey

Examples

• Package (JWE)
• Package (JWS)
• Encrypter (Encrypt)
• Encrypter (EncryptWithAuthData)
• NewEncrypter (PublicKey)
• NewEncrypter (Symmetric)
• NewMultiEncrypter
• NewMultiSigner
• NewSigner (PublicKey)
• NewSigner (Symmetric)

Constants

const (
	ED25519            = KeyAlgorithm("ED25519")
	RSA1_5             = KeyAlgorithm("RSA1_5")             // RSA-PKCS1v1.5
	RSA_OAEP           = KeyAlgorithm("RSA-OAEP")           // RSA-OAEP-SHA1
	RSA_OAEP_256       = KeyAlgorithm("RSA-OAEP-256")       // RSA-OAEP-SHA256
	A128KW             = KeyAlgorithm("A128KW")             // AES key wrap (128)
	A192KW             = KeyAlgorithm("A192KW")             // AES key wrap (192)
	A256KW             = KeyAlgorithm("A256KW")             // AES key wrap (256)
	DIRECT             = KeyAlgorithm("dir")                // Direct encryption
	ECDH_ES            = KeyAlgorithm("ECDH-ES")            // ECDH-ES
	ECDH_ES_A128KW     = KeyAlgorithm("ECDH-ES+A128KW")     // ECDH-ES + AES key wrap (128)
	ECDH_ES_A192KW     = KeyAlgorithm("ECDH-ES+A192KW")     // ECDH-ES + AES key wrap (192)
	ECDH_ES_A256KW     = KeyAlgorithm("ECDH-ES+A256KW")     // ECDH-ES + AES key wrap (256)
	A128GCMKW          = KeyAlgorithm("A128GCMKW")          // AES-GCM key wrap (128)
	A192GCMKW          = KeyAlgorithm("A192GCMKW")          // AES-GCM key wrap (192)
	A256GCMKW          = KeyAlgorithm("A256GCMKW")          // AES-GCM key wrap (256)
	PBES2_HS256_A128KW = KeyAlgorithm("PBES2-HS256+A128KW") // PBES2 + HMAC-SHA256 + AES key wrap (128)
	PBES2_HS384_A192KW = KeyAlgorithm("PBES2-HS384+A192KW") // PBES2 + HMAC-SHA384 + AES key wrap (192)
	PBES2_HS512_A256KW = KeyAlgorithm("PBES2-HS512+A256KW") // PBES2 + HMAC-SHA512 + AES key wrap (256)
)

Key management algorithms

const (
	EdDSA = SignatureAlgorithm("EdDSA")
	HS256 = SignatureAlgorithm("HS256") // HMAC using SHA-256
	HS384 = SignatureAlgorithm("HS384") // HMAC using SHA-384
	HS512 = SignatureAlgorithm("HS512") // HMAC using SHA-512
	RS256 = SignatureAlgorithm("RS256") // RSASSA-PKCS-v1.5 using SHA-256
	RS384 = SignatureAlgorithm("RS384") // RSASSA-PKCS-v1.5 using SHA-384
	RS512 = SignatureAlgorithm("RS512") // RSASSA-PKCS-v1.5 using SHA-512
	ES256 = SignatureAlgorithm("ES256") // ECDSA using P-256 and SHA-256
	ES384 = SignatureAlgorithm("ES384") // ECDSA using P-384 and SHA-384
	ES512 = SignatureAlgorithm("ES512") // ECDSA using P-521 and SHA-512
	PS256 = SignatureAlgorithm("PS256") // RSASSA-PSS using SHA256 and MGF1-SHA256
	PS384 = SignatureAlgorithm("PS384") // RSASSA-PSS using SHA384 and MGF1-SHA384
	PS512 = SignatureAlgorithm("PS512") // RSASSA-PSS using SHA512 and MGF1-SHA512
)

Signature algorithms

const (
	A128CBC_HS256 = ContentEncryption("A128CBC-HS256") // AES-CBC + HMAC-SHA256 (128)
	A192CBC_HS384 = ContentEncryption("A192CBC-HS384") // AES-CBC + HMAC-SHA384 (192)
	A256CBC_HS512 = ContentEncryption("A256CBC-HS512") // AES-CBC + HMAC-SHA512 (256)
	A128GCM       = ContentEncryption("A128GCM")       // AES-GCM (128)
	A192GCM       = ContentEncryption("A192GCM")       // AES-GCM (192)
	A256GCM       = ContentEncryption("A256GCM")       // AES-GCM (256)
)

Content encryption algorithms

const (
	NONE    = CompressionAlgorithm("")    // No compression
	DEFLATE = CompressionAlgorithm("DEF") // DEFLATE (RFC 1951)
)

Compression algorithms

Variables

var (
	// ErrCryptoFailure represents an error in cryptographic primitive. This
	// occurs when, for example, a message had an invalid authentication tag or
	// could not be decrypted.
	ErrCryptoFailure = errors.New("square/go-jose: error in cryptographic primitive")

	// ErrUnsupportedAlgorithm indicates that a selected algorithm is not
	// supported. This occurs when trying to instantiate an encrypter for an
	// algorithm that is not yet implemented.
	ErrUnsupportedAlgorithm = errors.New("square/go-jose: unknown/unsupported algorithm")

	// ErrUnsupportedKeyType indicates that the given key type/format is not
	// supported. This occurs when trying to instantiate an encrypter and passing
	// it a key of an unrecognized type or with unsupported parameters, such as
	// an RSA private key with more than two primes.
	ErrUnsupportedKeyType = errors.New("square/go-jose: unsupported key type/format")

	// ErrInvalidKeySize indicates that the given key is not the correct size
	// for the selected algorithm. This can occur, for example, when trying to
	// encrypt with AES-256 but passing only a 128-bit key as input.
	ErrInvalidKeySize = errors.New("square/go-jose: invalid key size for algorithm")

	// ErrNotSupported serialization of object is not supported. This occurs when
	// trying to compact-serialize an object which can't be represented in
	// compact form.
	ErrNotSupported = errors.New("square/go-jose: compact serialization not supported for object")

	// ErrUnprotectedNonce indicates that while parsing a JWS or JWE object, a
	// nonce header parameter was included in an unprotected header object.
	ErrUnprotectedNonce = errors.New("square/go-jose: Nonce parameter included in unprotected header")
)

var RandReader = rand.Reader

Random reader (stubbed out in tests)

Types

type CompressionAlgorithm

type CompressionAlgorithm string

CompressionAlgorithm represents an algorithm used for plaintext compression.

type ContentEncryption

type ContentEncryption string

ContentEncryption represents a content encryption algorithm.

type ContentType

type ContentType string

ContentType represents type of the contained data.

type Encrypter

type Encrypter interface {
	Encrypt(plaintext []byte) (*JSONWebEncryption, error)
	EncryptWithAuthData(plaintext []byte, aad []byte) (*JSONWebEncryption, error)
	Options() EncrypterOptions
}

Encrypter represents an encrypter which produces an encrypted JWE object.

Example (Encrypt)

// Encrypt a plaintext in order to get an encrypted JWE object.
var plaintext = []byte("This is a secret message")

encrypter.Encrypt(plaintext)

Example (EncryptWithAuthData)

// Encrypt a plaintext in order to get an encrypted JWE object. Also attach
// some additional authenticated data (AAD) to the object. Note that objects
// with attached AAD can only be represented using full serialization.
var plaintext = []byte("This is a secret message")
var aad = []byte("This is authenticated, but public data")

encrypter.EncryptWithAuthData(plaintext, aad)

func NewEncrypter

func NewEncrypter(enc ContentEncryption, rcpt Recipient, opts *EncrypterOptions) (Encrypter, error)

NewEncrypter creates an appropriate encrypter based on the key type

Example (PublicKey)

var publicKey *rsa.PublicKey

// Instantiate an encrypter using RSA-OAEP with AES128-GCM.
NewEncrypter(A128GCM, Recipient{Algorithm: RSA_OAEP, Key: publicKey}, nil)

// Instantiate an encrypter using RSA-PKCS1v1.5 with AES128-CBC+HMAC.
NewEncrypter(A128CBC_HS256, Recipient{Algorithm: RSA1_5, Key: publicKey}, nil)

Example (Symmetric)

var sharedKey []byte

// Instantiate an encrypter using AES128-GCM with AES-GCM key wrap.
NewEncrypter(A128GCM, Recipient{Algorithm: A128GCMKW, Key: sharedKey}, nil)

// Instantiate an encrypter using AES128-GCM directly, w/o key wrapping.
NewEncrypter(A128GCM, Recipient{Algorithm: DIRECT, Key: sharedKey}, nil)

func NewMultiEncrypter

func NewMultiEncrypter(enc ContentEncryption, rcpts []Recipient, opts *EncrypterOptions) (Encrypter, error)

NewMultiEncrypter creates a multi-encrypter based on the given parameters

Example

var publicKey *rsa.PublicKey
var sharedKey []byte

// Instantiate an encrypter using AES-GCM.
NewMultiEncrypter(A128GCM, []Recipient{
	{Algorithm: A128GCMKW, Key: sharedKey},
	{Algorithm: RSA_OAEP, Key: publicKey},
}, nil)

type EncrypterOptions

type EncrypterOptions struct {
	Compression CompressionAlgorithm

	// Optional map of additional keys to be inserted into the protected header
	// of a JWS object. Some specifications which make use of JWS like to insert
	// additional values here. All values must be JSON-serializable.
	ExtraHeaders map[HeaderKey]interface{}
}

EncrypterOptions represents options that can be set on new encrypters.

func (*EncrypterOptions) WithContentType

func (eo *EncrypterOptions) WithContentType(contentType ContentType) *EncrypterOptions

WithContentType adds a content type ("cty") header and returns the updated EncrypterOptions.

func (*EncrypterOptions) WithHeader

func (eo *EncrypterOptions) WithHeader(k HeaderKey, v interface{}) *EncrypterOptions

WithHeader adds an arbitrary value to the ExtraHeaders map, initializing it if necessary. It returns itself and so can be used in a fluent style.

func (*EncrypterOptions) WithType

func (eo *EncrypterOptions) WithType(typ ContentType) *EncrypterOptions

WithType adds a type ("typ") header and returns the updated EncrypterOptions.

type Header

type Header struct {
	KeyID      string
	JSONWebKey *JSONWebKey
	Algorithm  string
	Nonce      string

	// Any headers not recognised above get unmarshaled
	// from JSON in a generic manner and placed in this map.
	ExtraHeaders map[HeaderKey]interface{}
	// contains filtered or unexported fields
}

Header represents the read-only JOSE header for JWE/JWS objects.

func (Header) Certificates

func (h Header) Certificates(opts x509.VerifyOptions) ([][]*x509.Certificate, error)

Certificates verifies & returns the certificate chain present in the x5c header field of a message, if one was present. Returns an error if there was no x5c header present or the chain could not be validated with the given verify options.

type HeaderKey

type HeaderKey string

A key in the protected header of a JWS object. Use of the Header... constants is preferred to enhance type safety.

const (
	HeaderType        HeaderKey = "typ" // string
	HeaderContentType           = "cty" // string

)

type JSONWebEncryption

type JSONWebEncryption struct {
	Header Header
	// contains filtered or unexported fields
}

JSONWebEncryption represents an encrypted JWE object after parsing.

func ParseEncrypted

func ParseEncrypted(input string) (*JSONWebEncryption, error)

ParseEncrypted parses an encrypted message in compact or full serialization format.

func (JSONWebEncryption) CompactSerialize

func (obj JSONWebEncryption) CompactSerialize() (string, error)

CompactSerialize serializes an object using the compact serialization format.

func (JSONWebEncryption) Decrypt

func (obj JSONWebEncryption) Decrypt(decryptionKey interface{}) ([]byte, error)

Decrypt and validate the object and return the plaintext. Note that this function does not support multi-recipient, if you desire multi-recipient decryption use DecryptMulti instead.

func (JSONWebEncryption) DecryptMulti

func (obj JSONWebEncryption) DecryptMulti(decryptionKey interface{}) (int, Header, []byte, error)

DecryptMulti decrypts and validates the object and returns the plaintexts, with support for multiple recipients. It returns the index of the recipient for which the decryption was successful, the merged headers for that recipient, and the plaintext.

func (JSONWebEncryption) FullSerialize

func (obj JSONWebEncryption) FullSerialize() string

FullSerialize serializes an object using the full JSON serialization format.

func (JSONWebEncryption) GetAuthData

func (obj JSONWebEncryption) GetAuthData() []byte

GetAuthData retrieves the (optional) authenticated data attached to the object.

type JSONWebKey

type JSONWebKey struct {
	// Cryptographic key, can be a symmetric or asymmetric key.
	Key interface{}
	// Key identifier, parsed from `kid` header.
	KeyID string
	// Key algorithm, parsed from `alg` header.
	Algorithm string
	// Key use, parsed from `use` header.
	Use string

	// X.509 certificate chain, parsed from `x5c` header.
	Certificates []*x509.Certificate
	// X.509 certificate URL, parsed from `x5u` header.
	CertificatesURL *url.URL
	// X.509 certificate thumbprint (SHA-1), parsed from `x5t` header.
	CertificateThumbprintSHA1 []byte
	// X.509 certificate thumbprint (SHA-256), parsed from `x5t#S256` header.
	CertificateThumbprintSHA256 []byte
}

JSONWebKey represents a public or private key in JWK format.

func (*JSONWebKey) IsPublic

func (k *JSONWebKey) IsPublic() bool

IsPublic returns true if the JWK represents a public key (not symmetric, not private).

func (JSONWebKey) MarshalJSON

func (k JSONWebKey) MarshalJSON() ([]byte, error)

MarshalJSON serializes the given key to its JSON representation.

func (*JSONWebKey) Public

func (k *JSONWebKey) Public() JSONWebKey

Public creates JSONWebKey with corresponding publik key if JWK represents asymmetric private key.

func (*JSONWebKey) Thumbprint

func (k *JSONWebKey) Thumbprint(hash crypto.Hash) ([]byte, error)

Thumbprint computes the JWK Thumbprint of a key using the indicated hash algorithm.

func (*JSONWebKey) UnmarshalJSON

func (k *JSONWebKey) UnmarshalJSON(data []byte) (err error)

UnmarshalJSON reads a key from its JSON representation.

func (*JSONWebKey) Valid

func (k *JSONWebKey) Valid() bool

Valid checks that the key contains the expected parameters.

type JSONWebKeySet

type JSONWebKeySet struct {
	Keys []JSONWebKey `json:"keys"`
}

JSONWebKeySet represents a JWK Set object.

func (*JSONWebKeySet) Key

func (s *JSONWebKeySet) Key(kid string) []JSONWebKey

Key convenience method returns keys by key ID. Specification states that a JWK Set "SHOULD" use distinct key IDs, but allows for some cases where they are not distinct. Hence method returns a slice of JSONWebKeys.

type JSONWebSignature

type JSONWebSignature struct {

	// Signatures attached to this object (may be more than one for multi-sig).
	// Be careful about accessing these directly, prefer to use Verify() or
	// VerifyMulti() to ensure that the data you're getting is verified.
	Signatures []Signature
	// contains filtered or unexported fields
}

JSONWebSignature represents a signed JWS object after parsing.

func ParseDetached

func ParseDetached(signature string, payload []byte) (*JSONWebSignature, error)

ParseDetached parses a signed message in compact serialization format with detached payload.

func ParseSigned

func ParseSigned(signature string) (*JSONWebSignature, error)

ParseSigned parses a signed message in compact or full serialization format.

func (JSONWebSignature) CompactSerialize

func (obj JSONWebSignature) CompactSerialize() (string, error)

CompactSerialize serializes an object using the compact serialization format.

func (JSONWebSignature) DetachedCompactSerialize

func (obj JSONWebSignature) DetachedCompactSerialize() (string, error)

DetachedCompactSerialize serializes an object using the compact serialization format with detached payload.

func (JSONWebSignature) DetachedVerify

func (obj JSONWebSignature) DetachedVerify(payload []byte, verificationKey interface{}) error

DetachedVerify validates a detached signature on the given payload. In most cases, you will probably want to use Verify instead. DetachedVerify is only useful if you have a payload and signature that are separated from each other.

func (JSONWebSignature) DetachedVerifyMulti

func (obj JSONWebSignature) DetachedVerifyMulti(payload []byte, verificationKey interface{}) (int, Signature, error)

DetachedVerifyMulti validates a detached signature on the given payload with a signature/object that has potentially multiple signers. This returns the index of the signature that was verified, along with the signature object. We return the signature and index to guarantee that callers are getting the verified value.

In most cases, you will probably want to use Verify or VerifyMulti instead. DetachedVerifyMulti is only useful if you have a payload and signature that are separated from each other, and the signature can have multiple signers at the same time.

func (JSONWebSignature) FullSerialize

func (obj JSONWebSignature) FullSerialize() string

FullSerialize serializes an object using the full JSON serialization format.

func (JSONWebSignature) UnsafePayloadWithoutVerification

func (obj JSONWebSignature) UnsafePayloadWithoutVerification() []byte

UnsafePayloadWithoutVerification returns the payload without verifying it. The content returned from this function cannot be trusted.

func (JSONWebSignature) Verify

func (obj JSONWebSignature) Verify(verificationKey interface{}) ([]byte, error)

Verify validates the signature on the object and returns the payload. This function does not support multi-signature, if you desire multi-sig verification use VerifyMulti instead.

Be careful when verifying signatures based on embedded JWKs inside the payload header. You cannot assume that the key received in a payload is trusted.

func (JSONWebSignature) VerifyMulti

func (obj JSONWebSignature) VerifyMulti(verificationKey interface{}) (int, Signature, []byte, error)

VerifyMulti validates (one of the multiple) signatures on the object and returns the index of the signature that was verified, along with the signature object and the payload. We return the signature and index to guarantee that callers are getting the verified value.

type KeyAlgorithm

type KeyAlgorithm string

KeyAlgorithm represents a key management algorithm.

type NonceSource

type NonceSource interface {
	Nonce() (string, error)
}

NonceSource represents a source of random nonces to go into JWS objects

type OpaqueKeyDecrypter

type OpaqueKeyDecrypter interface {
	DecryptKey(encryptedKey []byte, header Header) ([]byte, error)
}

OpaqueKeyDecrypter is an interface that supports decrypting keys with an opaque key.

type OpaqueKeyEncrypter

type OpaqueKeyEncrypter interface {
	// KeyID returns the kid
	KeyID() string
	// Algs returns a list of supported key encryption algorithms.
	Algs() []KeyAlgorithm
	// contains filtered or unexported methods
}

OpaqueKeyEncrypter is an interface that supports encrypting keys with an opaque key.

type OpaqueSigner

type OpaqueSigner interface {
	// Public returns the public key of the current signing key.
	Public() *JSONWebKey
	// Algs returns a list of supported signing algorithms.
	Algs() []SignatureAlgorithm
	// SignPayload signs a payload with the current signing key using the given
	// algorithm.
	SignPayload(payload []byte, alg SignatureAlgorithm) ([]byte, error)
}

OpaqueSigner is an interface that supports signing payloads with opaque private key(s). Private key operations preformed by implementors may, for example, occur in a hardware module. An OpaqueSigner may rotate signing keys transparently to the user of this interface.

type OpaqueVerifier

type OpaqueVerifier interface {
	VerifyPayload(payload []byte, signature []byte, alg SignatureAlgorithm) error
}

OpaqueVerifier is an interface that supports verifying payloads with opaque public key(s). An OpaqueSigner may rotate signing keys transparently to the user of this interface.

type Recipient

type Recipient struct {
	Algorithm  KeyAlgorithm
	Key        interface{}
	KeyID      string
	PBES2Count int
	PBES2Salt  []byte
}

Recipient represents an algorithm/key to encrypt messages to.

PBES2Count and PBES2Salt correspond with the "p2c" and "p2s" headers used on the password-based encryption algorithms PBES2-HS256+A128KW, PBES2-HS384+A192KW, and PBES2-HS512+A256KW. If they are not provided a safe default of 100000 will be used for the count and a 128-bit random salt will be generated.

type Signature

type Signature struct {
	// Merged header fields. Contains both protected and unprotected header
	// values. Prefer using Protected and Unprotected fields instead of this.
	// Values in this header may or may not have been signed and in general
	// should not be trusted.
	Header Header

	// Protected header. Values in this header were signed and
	// will be verified as part of the signature verification process.
	Protected Header

	// Unprotected header. Values in this header were not signed
	// and in general should not be trusted.
	Unprotected Header

	// The actual signature value
	Signature []byte
	// contains filtered or unexported fields
}

Signature represents a single signature over the JWS payload and protected header.

type SignatureAlgorithm

type SignatureAlgorithm string

SignatureAlgorithm represents a signature (or MAC) algorithm.

type Signer

type Signer interface {
	Sign(payload []byte) (*JSONWebSignature, error)
	Options() SignerOptions
}

Signer represents a signer which takes a payload and produces a signed JWS object.

func NewMultiSigner

func NewMultiSigner(sigs []SigningKey, opts *SignerOptions) (Signer, error)

NewMultiSigner creates a signer for multiple recipients

Example

var privateKey *rsa.PrivateKey
var sharedKey []byte

// Instantiate a signer for multiple recipients.
NewMultiSigner([]SigningKey{
	{Algorithm: HS256, Key: sharedKey},
	{Algorithm: PS384, Key: privateKey},
}, nil)

func NewSigner

func NewSigner(sig SigningKey, opts *SignerOptions) (Signer, error)

NewSigner creates an appropriate signer based on the key type

Example (PublicKey)

var rsaPrivateKey *rsa.PrivateKey
var ecdsaPrivateKey *ecdsa.PrivateKey

// Instantiate a signer using RSA-PKCS#1v1.5 with SHA-256.
NewSigner(SigningKey{Algorithm: RS256, Key: rsaPrivateKey}, nil)

// Instantiate a signer using ECDSA with SHA-384.
NewSigner(SigningKey{Algorithm: ES384, Key: ecdsaPrivateKey}, nil)

Example (Symmetric)

var sharedKey []byte

// Instantiate an signer using HMAC-SHA256.
NewSigner(SigningKey{Algorithm: HS256, Key: sharedKey}, nil)

// Instantiate an signer using HMAC-SHA512.
NewSigner(SigningKey{Algorithm: HS512, Key: sharedKey}, nil)

type SignerOptions

type SignerOptions struct {
	NonceSource NonceSource
	EmbedJWK    bool

	// Optional map of additional keys to be inserted into the protected header
	// of a JWS object. Some specifications which make use of JWS like to insert
	// additional values here. All values must be JSON-serializable.
	ExtraHeaders map[HeaderKey]interface{}
}

SignerOptions represents options that can be set when creating signers.

func (*SignerOptions) WithBase64

func (so *SignerOptions) WithBase64(b64 bool) *SignerOptions

WithBase64 adds a base64url-encode payload ("b64") header and returns the updated SignerOptions. When the "b64" value is "false", the payload is not base64 encoded.

func (*SignerOptions) WithContentType

func (so *SignerOptions) WithContentType(contentType ContentType) *SignerOptions

WithContentType adds a content type ("cty") header and returns the updated SignerOptions.

func (*SignerOptions) WithCritical

func (so *SignerOptions) WithCritical(names ...string) *SignerOptions

WithCritical adds the given names to the critical ("crit") header and returns the updated SignerOptions.

func (*SignerOptions) WithHeader

func (so *SignerOptions) WithHeader(k HeaderKey, v interface{}) *SignerOptions

WithHeader adds an arbitrary value to the ExtraHeaders map, initializing it if necessary. It returns itself and so can be used in a fluent style.

func (*SignerOptions) WithType

func (so *SignerOptions) WithType(typ ContentType) *SignerOptions

WithType adds a type ("typ") header and returns the updated SignerOptions.

type SigningKey

type SigningKey struct {
	Algorithm SignatureAlgorithm
	Key       interface{}
}

SigningKey represents an algorithm/key used to sign a message.