forked from gitea/go-sdk
John Olheiser
321bd56d93
This PR adds a func for verifying incoming webhooks from Gitea, as well as a middleware for easier addition to a router stack. Co-authored-by: jolheiser <john.olheiser@gmail.com> Reviewed-on: gitea/go-sdk#580 Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com> Reviewed-by: Gusted <williamzijl7@hotmail.com>
60 lines
1.6 KiB
Go
60 lines
1.6 KiB
Go
// Copyright 2022 The Gitea Authors. All rights reserved.
|
|
// Use of this source code is governed by a MIT-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package gitea
|
|
|
|
import (
|
|
"bytes"
|
|
"crypto/hmac"
|
|
"crypto/sha256"
|
|
"encoding/hex"
|
|
"io"
|
|
"net/http"
|
|
)
|
|
|
|
// VerifyWebhookSignature verifies that a payload matches the X-Gitea-Signature based on a secret
|
|
func VerifyWebhookSignature(secret, expected string, payload []byte) (bool, error) {
|
|
hash := hmac.New(sha256.New, []byte(secret))
|
|
if _, err := hash.Write(payload); err != nil {
|
|
return false, err
|
|
}
|
|
expectedSum, err := hex.DecodeString(expected)
|
|
if err != nil {
|
|
return false, err
|
|
}
|
|
return hmac.Equal(hash.Sum(nil), expectedSum), nil
|
|
}
|
|
|
|
// VerifyWebhookSignatureMiddleware is a http.Handler for verifying X-Gitea-Signature on incoming webhooks
|
|
func VerifyWebhookSignatureMiddleware(secret string) func(http.Handler) http.Handler {
|
|
return func(next http.Handler) http.Handler {
|
|
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
|
|
var b bytes.Buffer
|
|
if _, err := io.Copy(&b, r.Body); err != nil {
|
|
http.Error(w, err.Error(), http.StatusBadRequest)
|
|
return
|
|
}
|
|
|
|
expected := r.Header.Get("X-Gitea-Signature")
|
|
if expected == "" {
|
|
http.Error(w, "no signature found", http.StatusBadRequest)
|
|
return
|
|
}
|
|
|
|
ok, err := VerifyWebhookSignature(secret, expected, b.Bytes())
|
|
if err != nil {
|
|
http.Error(w, err.Error(), http.StatusUnauthorized)
|
|
return
|
|
}
|
|
if !ok {
|
|
http.Error(w, "invalid payload", http.StatusUnauthorized)
|
|
return
|
|
}
|
|
|
|
r.Body = io.NopCloser(&b)
|
|
next.ServeHTTP(w, r)
|
|
})
|
|
}
|
|
}
|