act/pkg/artifactcache/mac.go

54 lines
1.1 KiB
Go

// Copyright 2024 The Forgejo Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package artifactcache
import (
"crypto/hmac"
"crypto/sha256"
"encoding/hex"
"errors"
"strconv"
"time"
"github.com/nektos/act/pkg/cacheproxy"
)
var (
ErrValidation = errors.New("validation error")
)
func (h *Handler) validateMac(rundata cacheproxy.RunData) (string, error) {
// TODO: allow configurable max age
if !validateAge(rundata.Timestamp) {
return "", ErrValidation
}
expectedMAC := computeMac(h.secret, rundata.RepositoryFullName, rundata.RunNumber, rundata.Timestamp)
if hmac.Equal([]byte(expectedMAC), []byte(rundata.RepositoryMAC)) {
return rundata.RepositoryFullName, nil
}
return "", ErrValidation
}
func validateAge(ts string) bool {
tsInt, err := strconv.ParseInt(ts, 10, 64)
if err != nil {
return false
}
if tsInt > time.Now().Unix() {
return false
}
return true
}
func computeMac(secret, repo, run, ts string) string {
mac := hmac.New(sha256.New, []byte(secret))
mac.Write([]byte(repo))
mac.Write([]byte(">"))
mac.Write([]byte(run))
mac.Write([]byte(">"))
mac.Write([]byte(ts))
return hex.EncodeToString(mac.Sum(nil))
}