github.com/livekit/protocol@v1.16.1-0.20240517185851-47e4c6bba773/webhook/verifier.go (about)

     1  // Copyright 2023 LiveKit, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package webhook
    16  
    17  import (
    18  	"crypto/sha256"
    19  	"encoding/base64"
    20  	"io"
    21  	"net/http"
    22  
    23  	"google.golang.org/protobuf/encoding/protojson"
    24  
    25  	"github.com/livekit/protocol/auth"
    26  	"github.com/livekit/protocol/livekit"
    27  )
    28  
    29  // Receive reads and verifies incoming webhook is signed with key/secret pair
    30  // closes body after reading
    31  func Receive(r *http.Request, provider auth.KeyProvider) ([]byte, error) {
    32  	defer r.Body.Close()
    33  	data, err := io.ReadAll(r.Body)
    34  	if err != nil {
    35  		return nil, err
    36  	}
    37  
    38  	authToken := r.Header.Get(authHeader)
    39  	if authToken == "" {
    40  		return nil, ErrNoAuthHeader
    41  	}
    42  
    43  	v, err := auth.ParseAPIToken(authToken)
    44  	if err != nil {
    45  		return nil, err
    46  	}
    47  
    48  	secret := provider.GetSecret(v.APIKey())
    49  	if secret == "" {
    50  		return nil, ErrSecretNotFound
    51  	}
    52  
    53  	claims, err := v.Verify(secret)
    54  	if err != nil {
    55  		return nil, err
    56  	}
    57  
    58  	// verify checksum
    59  	sha := sha256.Sum256(data)
    60  	hash := base64.StdEncoding.EncodeToString(sha[:])
    61  
    62  	if claims.Sha256 != hash {
    63  		return nil, ErrInvalidChecksum
    64  	}
    65  
    66  	return data, nil
    67  }
    68  
    69  // ReceiveWebhookEvent reads and verifies incoming webhook, and returns a parsed WebhookEvent
    70  func ReceiveWebhookEvent(r *http.Request, provider auth.KeyProvider) (*livekit.WebhookEvent, error) {
    71  	data, err := Receive(r, provider)
    72  	if err != nil {
    73  		return nil, err
    74  	}
    75  	unmarshalOpts := protojson.UnmarshalOptions{
    76  		DiscardUnknown: true,
    77  		AllowPartial:   true,
    78  	}
    79  	event := livekit.WebhookEvent{}
    80  	if err = unmarshalOpts.Unmarshal(data, &event); err != nil {
    81  		return nil, err
    82  	}
    83  	return &event, nil
    84  }