gophish/webhook/webhook.go

114 lines
2.7 KiB
Go

package webhook
import (
"bytes"
"crypto/hmac"
"crypto/sha256"
"encoding/hex"
"encoding/json"
"errors"
"fmt"
"net/http"
"time"
log "github.com/gophish/gophish/logger"
)
const (
// DefaultTimeoutSeconds is amount of seconds of timeout used by HTTP sender
DefaultTimeoutSeconds = 10
// MinHTTPStatusErrorCode is the lowest number of an HTTP response which indicates an error
MinHTTPStatusErrorCode = 400
// SignatureHeader is the name of an HTTP header used to which contains signature of a webhook
SignatureHeader = "X-Gophish-Signature"
// Sha256Prefix is the prefix that specifies the hashing algorithm used for signature
Sha256Prefix = "sha256"
)
// Sender defines behaviour of an entity by which webhook is sent
type Sender interface {
Send(endPoint EndPoint, data interface{}) error
}
type defaultSender struct {
client *http.Client
}
var senderInstance = &defaultSender{
client: &http.Client{
Timeout: time.Second * DefaultTimeoutSeconds,
CheckRedirect: func(req *http.Request, via []*http.Request) error {
return http.ErrUseLastResponse
},
},
}
// EndPoint represents and end point to send a webhook to: url and secret by which payload is signed
type EndPoint struct {
URL string
Secret string
}
// Send sends data to a single EndPoint
func Send(endPoint EndPoint, data interface{}) error {
return senderInstance.Send(endPoint, data)
}
// SendAll sends data to each of the EndPoints
func SendAll(endPoints []EndPoint, data interface{}) {
for _, ept := range endPoints {
go func(ept1 EndPoint) {
senderInstance.Send(ept1, data)
}(EndPoint{URL: ept.URL, Secret: ept.Secret})
}
}
// Send contains the implementation of sending webhook to an EndPoint
func (ds defaultSender) Send(endPoint EndPoint, data interface{}) error {
jsonData, err := json.Marshal(data)
if err != nil {
log.Error(err)
return err
}
req, err := http.NewRequest("POST", endPoint.URL, bytes.NewBuffer(jsonData))
if err != nil {
log.Error(err)
return err
}
signat, err := sign(endPoint.Secret, jsonData)
if err != nil {
log.Error(err)
return err
}
req.Header.Set(SignatureHeader, fmt.Sprintf("%s=%s", Sha256Prefix, signat))
req.Header.Set("Content-Type", "application/json")
resp, err := ds.client.Do(req)
if err != nil {
log.Error(err)
return err
}
defer resp.Body.Close()
if resp.StatusCode >= MinHTTPStatusErrorCode {
errMsg := fmt.Sprintf("http status of response: %s", resp.Status)
log.Error(errMsg)
return errors.New(errMsg)
}
return nil
}
func sign(secret string, data []byte) (string, error) {
hash1 := hmac.New(sha256.New, []byte(secret))
_, err := hash1.Write(data)
if err != nil {
return "", err
}
hexStr := hex.EncodeToString(hash1.Sum(nil))
return hexStr, nil
}