diff options
Diffstat (limited to 'vendor/gopkg.in/square/go-jose.v2/jwk.go')
| -rw-r--r-- | vendor/gopkg.in/square/go-jose.v2/jwk.go | 174 |
1 files changed, 163 insertions, 11 deletions
diff --git a/vendor/gopkg.in/square/go-jose.v2/jwk.go b/vendor/gopkg.in/square/go-jose.v2/jwk.go index 6cb8adb84..2dc6aec4b 100644 --- a/vendor/gopkg.in/square/go-jose.v2/jwk.go +++ b/vendor/gopkg.in/square/go-jose.v2/jwk.go @@ -17,15 +17,20 @@ package jose import ( + "bytes" "crypto" "crypto/ecdsa" "crypto/elliptic" "crypto/rsa" + "crypto/sha1" + "crypto/sha256" "crypto/x509" "encoding/base64" + "encoding/hex" "errors" "fmt" "math/big" + "net/url" "reflect" "strings" @@ -57,16 +62,31 @@ type rawJSONWebKey struct { Dq *byteBuffer `json:"dq,omitempty"` Qi *byteBuffer `json:"qi,omitempty"` // Certificates - X5c []string `json:"x5c,omitempty"` + X5c []string `json:"x5c,omitempty"` + X5u *url.URL `json:"x5u,omitempty"` + X5tSHA1 string `json:"x5t,omitempty"` + X5tSHA256 string `json:"x5t#S256,omitempty"` } // JSONWebKey represents a public or private key in JWK format. type JSONWebKey struct { - Key interface{} + // 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 - KeyID string - Algorithm string - Use string + // 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 } // MarshalJSON serializes the given key to its JSON representation. @@ -105,6 +125,39 @@ func (k JSONWebKey) MarshalJSON() ([]byte, error) { raw.X5c = append(raw.X5c, base64.StdEncoding.EncodeToString(cert.Raw)) } + x5tSHA1Len := len(k.CertificateThumbprintSHA1) + x5tSHA256Len := len(k.CertificateThumbprintSHA256) + if x5tSHA1Len > 0 { + if x5tSHA1Len != sha1.Size { + return nil, fmt.Errorf("square/go-jose: invalid SHA-1 thumbprint (must be %d bytes, not %d)", sha1.Size, x5tSHA1Len) + } + raw.X5tSHA1 = base64.RawURLEncoding.EncodeToString(k.CertificateThumbprintSHA1) + } + if x5tSHA256Len > 0 { + if x5tSHA256Len != sha256.Size { + return nil, fmt.Errorf("square/go-jose: invalid SHA-256 thumbprint (must be %d bytes, not %d)", sha256.Size, x5tSHA256Len) + } + raw.X5tSHA256 = base64.RawURLEncoding.EncodeToString(k.CertificateThumbprintSHA256) + } + + // If cert chain is attached (as opposed to being behind a URL), check the + // keys thumbprints to make sure they match what is expected. This is to + // ensure we don't accidentally produce a JWK with semantically inconsistent + // data in the headers. + if len(k.Certificates) > 0 { + expectedSHA1 := sha1.Sum(k.Certificates[0].Raw) + expectedSHA256 := sha256.Sum256(k.Certificates[0].Raw) + + if len(k.CertificateThumbprintSHA1) > 0 && !bytes.Equal(k.CertificateThumbprintSHA1, expectedSHA1[:]) { + return nil, errors.New("square/go-jose: invalid SHA-1 thumbprint, does not match cert chain") + } + if len(k.CertificateThumbprintSHA256) > 0 && !bytes.Equal(k.CertificateThumbprintSHA256, expectedSHA256[:]) { + return nil, errors.New("square/go-jose: invalid or SHA-256 thumbprint, does not match cert chain") + } + } + + raw.X5u = k.CertificatesURL + return json.Marshal(raw) } @@ -116,28 +169,61 @@ func (k *JSONWebKey) UnmarshalJSON(data []byte) (err error) { return err } + certs, err := parseCertificateChain(raw.X5c) + if err != nil { + return fmt.Errorf("square/go-jose: failed to unmarshal x5c field: %s", err) + } + var key interface{} + var certPub interface{} + var keyPub interface{} + + if len(certs) > 0 { + // We need to check that leaf public key matches the key embedded in this + // JWK, as required by the standard (see RFC 7517, Section 4.7). Otherwise + // the JWK parsed could be semantically invalid. Technically, should also + // check key usage fields and other extensions on the cert here, but the + // standard doesn't exactly explain how they're supposed to map from the + // JWK representation to the X.509 extensions. + certPub = certs[0].PublicKey + } + switch raw.Kty { case "EC": if raw.D != nil { key, err = raw.ecPrivateKey() + if err == nil { + keyPub = key.(*ecdsa.PrivateKey).Public() + } } else { key, err = raw.ecPublicKey() + keyPub = key } case "RSA": if raw.D != nil { key, err = raw.rsaPrivateKey() + if err == nil { + keyPub = key.(*rsa.PrivateKey).Public() + } } else { key, err = raw.rsaPublicKey() + keyPub = key } case "oct": + if certPub != nil { + return errors.New("square/go-jose: invalid JWK, found 'oct' (symmetric) key with cert chain") + } key, err = raw.symmetricKey() case "OKP": if raw.Crv == "Ed25519" && raw.X != nil { if raw.D != nil { key, err = raw.edPrivateKey() + if err == nil { + keyPub = key.(ed25519.PrivateKey).Public() + } } else { key, err = raw.edPublicKey() + keyPub = key } } else { err = fmt.Errorf("square/go-jose: unknown curve %s'", raw.Crv) @@ -146,12 +232,78 @@ func (k *JSONWebKey) UnmarshalJSON(data []byte) (err error) { err = fmt.Errorf("square/go-jose: unknown json web key type '%s'", raw.Kty) } - if err == nil { - *k = JSONWebKey{Key: key, KeyID: raw.Kid, Algorithm: raw.Alg, Use: raw.Use} + if err != nil { + return + } + + if certPub != nil && keyPub != nil { + if !reflect.DeepEqual(certPub, keyPub) { + return errors.New("square/go-jose: invalid JWK, public keys in key and x5c fields to not match") + } + } + + *k = JSONWebKey{Key: key, KeyID: raw.Kid, Algorithm: raw.Alg, Use: raw.Use, Certificates: certs} - k.Certificates, err = parseCertificateChain(raw.X5c) + k.CertificatesURL = raw.X5u + + // x5t parameters are base64url-encoded SHA thumbprints + // See RFC 7517, Section 4.8, https://tools.ietf.org/html/rfc7517#section-4.8 + x5tSHA1bytes, err := base64.RawURLEncoding.DecodeString(raw.X5tSHA1) + if err != nil { + return errors.New("square/go-jose: invalid JWK, x5t header has invalid encoding") + } + + // RFC 7517, Section 4.8 is ambiguous as to whether the digest output should be byte or hex, + // for this reason, after base64 decoding, if the size is sha1.Size it's likely that the value is a byte encoded + // checksum so we skip this. Otherwise if the checksum was hex encoded we expect a 40 byte sized array so we'll + // try to hex decode it. When Marshalling this value we'll always use a base64 encoded version of byte format checksum. + if len(x5tSHA1bytes) == 2*sha1.Size { + hx, err := hex.DecodeString(string(x5tSHA1bytes)) + if err != nil { + return fmt.Errorf("square/go-jose: invalid JWK, unable to hex decode x5t: %v", err) + + } + x5tSHA1bytes = hx + } + + k.CertificateThumbprintSHA1 = x5tSHA1bytes + + x5tSHA256bytes, err := base64.RawURLEncoding.DecodeString(raw.X5tSHA256) + if err != nil { + return errors.New("square/go-jose: invalid JWK, x5t#S256 header has invalid encoding") + } + + if len(x5tSHA256bytes) == 2*sha256.Size { + hx256, err := hex.DecodeString(string(x5tSHA256bytes)) if err != nil { - return fmt.Errorf("failed to unmarshal x5c field: %s", err) + return fmt.Errorf("square/go-jose: invalid JWK, unable to hex decode x5t#S256: %v", err) + } + x5tSHA256bytes = hx256 + } + + k.CertificateThumbprintSHA256 = x5tSHA256bytes + + x5tSHA1Len := len(k.CertificateThumbprintSHA1) + x5tSHA256Len := len(k.CertificateThumbprintSHA256) + if x5tSHA1Len > 0 && x5tSHA1Len != sha1.Size { + return errors.New("square/go-jose: invalid JWK, x5t header is of incorrect size") + } + if x5tSHA256Len > 0 && x5tSHA256Len != sha256.Size { + return errors.New("square/go-jose: invalid JWK, x5t#S256 header is of incorrect size") + } + + // If certificate chain *and* thumbprints are set, verify correctness. + if len(k.Certificates) > 0 { + leaf := k.Certificates[0] + sha1sum := sha1.Sum(leaf.Raw) + sha256sum := sha256.Sum256(leaf.Raw) + + if len(k.CertificateThumbprintSHA1) > 0 && !bytes.Equal(sha1sum[:], k.CertificateThumbprintSHA1) { + return errors.New("square/go-jose: invalid JWK, x5c thumbprint does not match x5t value") + } + + if len(k.CertificateThumbprintSHA256) > 0 && !bytes.Equal(sha256sum[:], k.CertificateThumbprintSHA256) { + return errors.New("square/go-jose: invalid JWK, x5c thumbprint does not match x5t#S256 value") } } @@ -357,11 +509,11 @@ func (key rawJSONWebKey) ecPublicKey() (*ecdsa.PublicKey, error) { // the curve specified in the "crv" parameter. // https://tools.ietf.org/html/rfc7518#section-6.2.1.2 if curveSize(curve) != len(key.X.data) { - return nil, fmt.Errorf("square/go-jose: invalid EC private key, wrong length for x") + return nil, fmt.Errorf("square/go-jose: invalid EC public key, wrong length for x") } if curveSize(curve) != len(key.Y.data) { - return nil, fmt.Errorf("square/go-jose: invalid EC private key, wrong length for y") + return nil, fmt.Errorf("square/go-jose: invalid EC public key, wrong length for y") } x := key.X.bigInt() |