storj/pkg/peertls/utils.go

72 lines
1.8 KiB
Go

// Copyright (C) 2019 Storj Labs, Inc.
// See LICENSE for copying information.
package peertls
// Many cryptography standards use ASN.1 to define their data structures,
// and Distinguished Encoding Rules (DER) to serialize those structures.
// Because DER produces binary output, it can be challenging to transmit
// the resulting files through systems, like electronic mail, that only
// support ASCII. The PEM format solves this problem by encoding the
// binary data using base64.
// (see https://en.wikipedia.org/wiki/Privacy-enhanced_Electronic_Mail)
import (
"crypto/rand"
"crypto/x509"
"crypto/x509/pkix"
"math/big"
"github.com/zeebo/errs"
"storj.io/storj/pkg/pkcrypto"
)
func verifyChainSignatures(certs []*x509.Certificate) error {
for i, cert := range certs {
j := len(certs)
if i+1 < j {
err := verifyCertSignature(certs[i+1], cert)
if err != nil {
return ErrVerifyCertificateChain.Wrap(err)
}
continue
}
err := verifyCertSignature(cert, cert)
if err != nil {
return ErrVerifyCertificateChain.Wrap(err)
}
}
return nil
}
func verifyCertSignature(parentCert, childCert *x509.Certificate) error {
return pkcrypto.VerifySignature(childCert.Signature, childCert.RawTBSCertificate, parentCert.PublicKey)
}
func newSerialNumber() (*big.Int, error) {
serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
if err != nil {
return nil, errs.New("failed to generateServerTls serial number: %s", err.Error())
}
return serialNumber, nil
}
func uniqueExts(exts []pkix.Extension) bool {
seen := make(map[string]struct{}, len(exts))
for _, e := range exts {
s := e.Id.String()
if _, ok := seen[s]; ok {
return false
}
seen[s] = struct{}{}
}
return true
}