peridot/vendor/gopkg.in/square/go-jose.v2/shared.go
2022-07-07 22:13:21 +02:00

521 lines
15 KiB
Go

/*-
* Copyright 2014 Square Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package jose
import (
"crypto/elliptic"
"crypto/x509"
"encoding/base64"
"errors"
"fmt"
"gopkg.in/square/go-jose.v2/json"
)
// KeyAlgorithm represents a key management algorithm.
type KeyAlgorithm string
// SignatureAlgorithm represents a signature (or MAC) algorithm.
type SignatureAlgorithm string
// ContentEncryption represents a content encryption algorithm.
type ContentEncryption string
// CompressionAlgorithm represents an algorithm used for plaintext compression.
type CompressionAlgorithm string
// ContentType represents type of the contained data.
type ContentType string
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")
)
// Key management algorithms
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)
)
// Signature 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
)
// Content encryption 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)
)
// Compression algorithms
const (
NONE = CompressionAlgorithm("") // No compression
DEFLATE = CompressionAlgorithm("DEF") // DEFLATE (RFC 1951)
)
// A key in the protected header of a JWS object. Use of the Header...
// constants is preferred to enhance type safety.
type HeaderKey string
const (
HeaderType HeaderKey = "typ" // string
HeaderContentType = "cty" // string
// These are set by go-jose and shouldn't need to be set by consumers of the
// library.
headerAlgorithm = "alg" // string
headerEncryption = "enc" // ContentEncryption
headerCompression = "zip" // CompressionAlgorithm
headerCritical = "crit" // []string
headerAPU = "apu" // *byteBuffer
headerAPV = "apv" // *byteBuffer
headerEPK = "epk" // *JSONWebKey
headerIV = "iv" // *byteBuffer
headerTag = "tag" // *byteBuffer
headerX5c = "x5c" // []*x509.Certificate
headerJWK = "jwk" // *JSONWebKey
headerKeyID = "kid" // string
headerNonce = "nonce" // string
headerB64 = "b64" // bool
headerP2C = "p2c" // *byteBuffer (int)
headerP2S = "p2s" // *byteBuffer ([]byte)
)
// supportedCritical is the set of supported extensions that are understood and processed.
var supportedCritical = map[string]bool{
headerB64: true,
}
// rawHeader represents the JOSE header for JWE/JWS objects (used for parsing).
//
// The decoding of the constituent items is deferred because we want to marshal
// some members into particular structs rather than generic maps, but at the
// same time we need to receive any extra fields unhandled by this library to
// pass through to consuming code in case it wants to examine them.
type rawHeader map[HeaderKey]*json.RawMessage
// Header represents the read-only JOSE header for JWE/JWS objects.
type Header struct {
KeyID string
JSONWebKey *JSONWebKey
Algorithm string
Nonce string
// Unverified certificate chain parsed from x5c header.
certificates []*x509.Certificate
// Any headers not recognised above get unmarshaled
// from JSON in a generic manner and placed in this map.
ExtraHeaders map[HeaderKey]interface{}
}
// 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.
func (h Header) Certificates(opts x509.VerifyOptions) ([][]*x509.Certificate, error) {
if len(h.certificates) == 0 {
return nil, errors.New("square/go-jose: no x5c header present in message")
}
leaf := h.certificates[0]
if opts.Intermediates == nil {
opts.Intermediates = x509.NewCertPool()
for _, intermediate := range h.certificates[1:] {
opts.Intermediates.AddCert(intermediate)
}
}
return leaf.Verify(opts)
}
func (parsed rawHeader) set(k HeaderKey, v interface{}) error {
b, err := json.Marshal(v)
if err != nil {
return err
}
parsed[k] = makeRawMessage(b)
return nil
}
// getString gets a string from the raw JSON, defaulting to "".
func (parsed rawHeader) getString(k HeaderKey) string {
v, ok := parsed[k]
if !ok || v == nil {
return ""
}
var s string
err := json.Unmarshal(*v, &s)
if err != nil {
return ""
}
return s
}
// getByteBuffer gets a byte buffer from the raw JSON. Returns (nil, nil) if
// not specified.
func (parsed rawHeader) getByteBuffer(k HeaderKey) (*byteBuffer, error) {
v := parsed[k]
if v == nil {
return nil, nil
}
var bb *byteBuffer
err := json.Unmarshal(*v, &bb)
if err != nil {
return nil, err
}
return bb, nil
}
// getAlgorithm extracts parsed "alg" from the raw JSON as a KeyAlgorithm.
func (parsed rawHeader) getAlgorithm() KeyAlgorithm {
return KeyAlgorithm(parsed.getString(headerAlgorithm))
}
// getSignatureAlgorithm extracts parsed "alg" from the raw JSON as a SignatureAlgorithm.
func (parsed rawHeader) getSignatureAlgorithm() SignatureAlgorithm {
return SignatureAlgorithm(parsed.getString(headerAlgorithm))
}
// getEncryption extracts parsed "enc" from the raw JSON.
func (parsed rawHeader) getEncryption() ContentEncryption {
return ContentEncryption(parsed.getString(headerEncryption))
}
// getCompression extracts parsed "zip" from the raw JSON.
func (parsed rawHeader) getCompression() CompressionAlgorithm {
return CompressionAlgorithm(parsed.getString(headerCompression))
}
func (parsed rawHeader) getNonce() string {
return parsed.getString(headerNonce)
}
// getEPK extracts parsed "epk" from the raw JSON.
func (parsed rawHeader) getEPK() (*JSONWebKey, error) {
v := parsed[headerEPK]
if v == nil {
return nil, nil
}
var epk *JSONWebKey
err := json.Unmarshal(*v, &epk)
if err != nil {
return nil, err
}
return epk, nil
}
// getAPU extracts parsed "apu" from the raw JSON.
func (parsed rawHeader) getAPU() (*byteBuffer, error) {
return parsed.getByteBuffer(headerAPU)
}
// getAPV extracts parsed "apv" from the raw JSON.
func (parsed rawHeader) getAPV() (*byteBuffer, error) {
return parsed.getByteBuffer(headerAPV)
}
// getIV extracts parsed "iv" frpom the raw JSON.
func (parsed rawHeader) getIV() (*byteBuffer, error) {
return parsed.getByteBuffer(headerIV)
}
// getTag extracts parsed "tag" frpom the raw JSON.
func (parsed rawHeader) getTag() (*byteBuffer, error) {
return parsed.getByteBuffer(headerTag)
}
// getJWK extracts parsed "jwk" from the raw JSON.
func (parsed rawHeader) getJWK() (*JSONWebKey, error) {
v := parsed[headerJWK]
if v == nil {
return nil, nil
}
var jwk *JSONWebKey
err := json.Unmarshal(*v, &jwk)
if err != nil {
return nil, err
}
return jwk, nil
}
// getCritical extracts parsed "crit" from the raw JSON. If omitted, it
// returns an empty slice.
func (parsed rawHeader) getCritical() ([]string, error) {
v := parsed[headerCritical]
if v == nil {
return nil, nil
}
var q []string
err := json.Unmarshal(*v, &q)
if err != nil {
return nil, err
}
return q, nil
}
// getS2C extracts parsed "p2c" from the raw JSON.
func (parsed rawHeader) getP2C() (int, error) {
v := parsed[headerP2C]
if v == nil {
return 0, nil
}
var p2c int
err := json.Unmarshal(*v, &p2c)
if err != nil {
return 0, err
}
return p2c, nil
}
// getS2S extracts parsed "p2s" from the raw JSON.
func (parsed rawHeader) getP2S() (*byteBuffer, error) {
return parsed.getByteBuffer(headerP2S)
}
// getB64 extracts parsed "b64" from the raw JSON, defaulting to true.
func (parsed rawHeader) getB64() (bool, error) {
v := parsed[headerB64]
if v == nil {
return true, nil
}
var b64 bool
err := json.Unmarshal(*v, &b64)
if err != nil {
return true, err
}
return b64, nil
}
// sanitized produces a cleaned-up header object from the raw JSON.
func (parsed rawHeader) sanitized() (h Header, err error) {
for k, v := range parsed {
if v == nil {
continue
}
switch k {
case headerJWK:
var jwk *JSONWebKey
err = json.Unmarshal(*v, &jwk)
if err != nil {
err = fmt.Errorf("failed to unmarshal JWK: %v: %#v", err, string(*v))
return
}
h.JSONWebKey = jwk
case headerKeyID:
var s string
err = json.Unmarshal(*v, &s)
if err != nil {
err = fmt.Errorf("failed to unmarshal key ID: %v: %#v", err, string(*v))
return
}
h.KeyID = s
case headerAlgorithm:
var s string
err = json.Unmarshal(*v, &s)
if err != nil {
err = fmt.Errorf("failed to unmarshal algorithm: %v: %#v", err, string(*v))
return
}
h.Algorithm = s
case headerNonce:
var s string
err = json.Unmarshal(*v, &s)
if err != nil {
err = fmt.Errorf("failed to unmarshal nonce: %v: %#v", err, string(*v))
return
}
h.Nonce = s
case headerX5c:
c := []string{}
err = json.Unmarshal(*v, &c)
if err != nil {
err = fmt.Errorf("failed to unmarshal x5c header: %v: %#v", err, string(*v))
return
}
h.certificates, err = parseCertificateChain(c)
if err != nil {
err = fmt.Errorf("failed to unmarshal x5c header: %v: %#v", err, string(*v))
return
}
default:
if h.ExtraHeaders == nil {
h.ExtraHeaders = map[HeaderKey]interface{}{}
}
var v2 interface{}
err = json.Unmarshal(*v, &v2)
if err != nil {
err = fmt.Errorf("failed to unmarshal value: %v: %#v", err, string(*v))
return
}
h.ExtraHeaders[k] = v2
}
}
return
}
func parseCertificateChain(chain []string) ([]*x509.Certificate, error) {
out := make([]*x509.Certificate, len(chain))
for i, cert := range chain {
raw, err := base64.StdEncoding.DecodeString(cert)
if err != nil {
return nil, err
}
out[i], err = x509.ParseCertificate(raw)
if err != nil {
return nil, err
}
}
return out, nil
}
func (dst rawHeader) isSet(k HeaderKey) bool {
dvr := dst[k]
if dvr == nil {
return false
}
var dv interface{}
err := json.Unmarshal(*dvr, &dv)
if err != nil {
return true
}
if dvStr, ok := dv.(string); ok {
return dvStr != ""
}
return true
}
// Merge headers from src into dst, giving precedence to headers from l.
func (dst rawHeader) merge(src *rawHeader) {
if src == nil {
return
}
for k, v := range *src {
if dst.isSet(k) {
continue
}
dst[k] = v
}
}
// Get JOSE name of curve
func curveName(crv elliptic.Curve) (string, error) {
switch crv {
case elliptic.P256():
return "P-256", nil
case elliptic.P384():
return "P-384", nil
case elliptic.P521():
return "P-521", nil
default:
return "", fmt.Errorf("square/go-jose: unsupported/unknown elliptic curve")
}
}
// Get size of curve in bytes
func curveSize(crv elliptic.Curve) int {
bits := crv.Params().BitSize
div := bits / 8
mod := bits % 8
if mod == 0 {
return div
}
return div + 1
}
func makeRawMessage(b []byte) *json.RawMessage {
rm := json.RawMessage(b)
return &rm
}