1 files changed, 67 insertions, 0 deletions
diff --git a/vendor/golang.org/x/crypto/acme/internal/acme/jws.go b/vendor/golang.org/x/crypto/acme/internal/acme/jws.go
new file mode 100644
index 000000000..c27752977
--- /dev/null
+++ b/vendor/golang.org/x/crypto/acme/internal/acme/jws.go
@@ -0,0 +1,67 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package acme
+
+import (
+	"crypto"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"math/big"
+)
+
+// jwsEncodeJSON signs claimset using provided key and a nonce.
+// The result is serialized in JSON format.
+// See https://tools.ietf.org/html/rfc7515#section-7.
+func jwsEncodeJSON(claimset interface{}, key *rsa.PrivateKey, nonce string) ([]byte, error) {
+	jwk := jwkEncode(&key.PublicKey)
+	phead := fmt.Sprintf(`{"alg":"RS256","jwk":%s,"nonce":%q}`, jwk, nonce)
+	phead = base64.RawURLEncoding.EncodeToString([]byte(phead))
+	cs, err := json.Marshal(claimset)
+	if err != nil {
+		return nil, err
+	}
+	payload := base64.RawURLEncoding.EncodeToString(cs)
+	h := sha256.New()
+	h.Write([]byte(phead + "." + payload))
+	sig, err := rsa.SignPKCS1v15(rand.Reader, key, crypto.SHA256, h.Sum(nil))
+	if err != nil {
+		return nil, err
+	}
+	enc := struct {
+		Protected string `json:"protected"`
+		Payload   string `json:"payload"`
+		Sig       string `json:"signature"`
+	}{
+		Protected: phead,
+		Payload:   payload,
+		Sig:       base64.RawURLEncoding.EncodeToString(sig),
+	}
+	return json.Marshal(&enc)
+}
+
+// jwkEncode encodes public part of an RSA key into a JWK.
+// The result is also suitable for creating a JWK thumbprint.
+func jwkEncode(pub *rsa.PublicKey) string {
+	n := pub.N
+	e := big.NewInt(int64(pub.E))
+	// fields order is important
+	// see https://tools.ietf.org/html/rfc7638#section-3.3 for details
+	return fmt.Sprintf(`{"e":"%s","kty":"RSA","n":"%s"}`,
+		base64.RawURLEncoding.EncodeToString(e.Bytes()),
+		base64.RawURLEncoding.EncodeToString(n.Bytes()),
+	)
+}
+
+// JWKThumbprint creates a JWK thumbprint out of pub
+// as specified in https://tools.ietf.org/html/rfc7638.
+func JWKThumbprint(pub *rsa.PublicKey) string {
+	jwk := jwkEncode(pub)
+	b := sha256.Sum256([]byte(jwk))
+	return base64.RawURLEncoding.EncodeToString(b[:])
+}