mirror of
https://github.com/42wim/matterbridge
synced 2024-11-09 07:10:25 +00:00
48 lines
1.4 KiB
Go
48 lines
1.4 KiB
Go
package slack
|
|
|
|
import (
|
|
"crypto/hmac"
|
|
"crypto/sha256"
|
|
"encoding/hex"
|
|
"errors"
|
|
"fmt"
|
|
"hash"
|
|
"net/http"
|
|
)
|
|
|
|
// SecretsVerifier contains the information needed to verify that the request comes from Slack
|
|
type SecretsVerifier struct {
|
|
slackSig string
|
|
timeStamp string
|
|
hmac hash.Hash
|
|
}
|
|
|
|
// NewSecretsVerifier returns a SecretsVerifier object in exchange for an http.Header object and signing secret
|
|
func NewSecretsVerifier(header http.Header, signingSecret string) (SecretsVerifier, error) {
|
|
if header["X-Slack-Signature"][0] == "" || header["X-Slack-Request-Timestamp"][0] == "" {
|
|
return SecretsVerifier{}, errors.New("Headers are empty, cannot create SecretsVerifier")
|
|
}
|
|
|
|
hash := hmac.New(sha256.New, []byte(signingSecret))
|
|
hash.Write([]byte(fmt.Sprintf("v0:%s:", header["X-Slack-Request-Timestamp"][0])))
|
|
return SecretsVerifier{
|
|
slackSig: header["X-Slack-Signature"][0],
|
|
timeStamp: header["X-Slack-Request-Timestamp"][0],
|
|
hmac: hash,
|
|
}, nil
|
|
}
|
|
|
|
func (v *SecretsVerifier) Write(body []byte) (n int, err error) {
|
|
return v.hmac.Write(body)
|
|
}
|
|
|
|
// Ensure compares the signature sent from Slack with the actual computed hash to judge validity
|
|
func (v SecretsVerifier) Ensure() error {
|
|
computed := "v0=" + string(hex.EncodeToString(v.hmac.Sum(nil)))
|
|
if computed == v.slackSig {
|
|
return nil
|
|
}
|
|
|
|
return fmt.Errorf("Expected signing signature: %s, but computed: %s", v.slackSig, computed)
|
|
}
|