traefik/vendor/github.com/xenolf/lego/acme/jws.go
2018-05-31 09:30:04 +02:00

167 lines
3.6 KiB
Go

package acme
import (
"bytes"
"crypto"
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rsa"
"fmt"
"net/http"
"sync"
"gopkg.in/square/go-jose.v2"
)
type jws struct {
getNonceURL string
privKey crypto.PrivateKey
kid string
nonces nonceManager
}
// Posts a JWS signed message to the specified URL.
// It does NOT close the response body, so the caller must
// do that if no error was returned.
func (j *jws) post(url string, content []byte) (*http.Response, error) {
signedContent, err := j.signContent(url, content)
if err != nil {
return nil, fmt.Errorf("failed to sign content -> %s", err.Error())
}
data := bytes.NewBuffer([]byte(signedContent.FullSerialize()))
resp, err := httpPost(url, "application/jose+json", data)
if err != nil {
return nil, fmt.Errorf("failed to HTTP POST to %s -> %s", url, err.Error())
}
nonce, nonceErr := getNonceFromResponse(resp)
if nonceErr == nil {
j.nonces.Push(nonce)
}
return resp, nil
}
func (j *jws) signContent(url string, content []byte) (*jose.JSONWebSignature, error) {
var alg jose.SignatureAlgorithm
switch k := j.privKey.(type) {
case *rsa.PrivateKey:
alg = jose.RS256
case *ecdsa.PrivateKey:
if k.Curve == elliptic.P256() {
alg = jose.ES256
} else if k.Curve == elliptic.P384() {
alg = jose.ES384
}
}
jsonKey := jose.JSONWebKey{
Key: j.privKey,
KeyID: j.kid,
}
signKey := jose.SigningKey{
Algorithm: alg,
Key: jsonKey,
}
options := jose.SignerOptions{
NonceSource: j,
ExtraHeaders: make(map[jose.HeaderKey]interface{}),
}
options.ExtraHeaders["url"] = url
if j.kid == "" {
options.EmbedJWK = true
}
signer, err := jose.NewSigner(signKey, &options)
if err != nil {
return nil, fmt.Errorf("failed to create jose signer -> %s", err.Error())
}
signed, err := signer.Sign(content)
if err != nil {
return nil, fmt.Errorf("failed to sign content -> %s", err.Error())
}
return signed, nil
}
func (j *jws) signEABContent(url, kid string, hmac []byte) (*jose.JSONWebSignature, error) {
jwk := jose.JSONWebKey{Key: j.privKey}
jwkJSON, err := jwk.Public().MarshalJSON()
if err != nil {
return nil, fmt.Errorf("acme: error encoding eab jwk key: %s", err.Error())
}
signer, err := jose.NewSigner(
jose.SigningKey{Algorithm: jose.HS256, Key: hmac},
&jose.SignerOptions{
EmbedJWK: false,
ExtraHeaders: map[jose.HeaderKey]interface{}{
"kid": kid,
"url": url,
},
},
)
if err != nil {
return nil, fmt.Errorf("failed to create External Account Binding jose signer -> %s", err.Error())
}
signed, err := signer.Sign(jwkJSON)
if err != nil {
return nil, fmt.Errorf("failed to External Account Binding sign content -> %s", err.Error())
}
return signed, nil
}
func (j *jws) Nonce() (string, error) {
if nonce, ok := j.nonces.Pop(); ok {
return nonce, nil
}
return getNonce(j.getNonceURL)
}
type nonceManager struct {
nonces []string
sync.Mutex
}
func (n *nonceManager) Pop() (string, bool) {
n.Lock()
defer n.Unlock()
if len(n.nonces) == 0 {
return "", false
}
nonce := n.nonces[len(n.nonces)-1]
n.nonces = n.nonces[:len(n.nonces)-1]
return nonce, true
}
func (n *nonceManager) Push(nonce string) {
n.Lock()
defer n.Unlock()
n.nonces = append(n.nonces, nonce)
}
func getNonce(url string) (string, error) {
resp, err := httpHead(url)
if err != nil {
return "", fmt.Errorf("failed to get nonce from HTTP HEAD -> %s", err.Error())
}
return getNonceFromResponse(resp)
}
func getNonceFromResponse(resp *http.Response) (string, error) {
nonce := resp.Header.Get("Replay-Nonce")
if nonce == "" {
return "", fmt.Errorf("server did not respond with a proper nonce header")
}
return nonce, nil
}