mirror of
https://github.com/ProtonMail/proton-bridge.git
synced 2025-12-10 04:36:43 +00:00
69 lines
1.8 KiB
Go
69 lines
1.8 KiB
Go
// Copyright (c) 2021 Proton Technologies AG
|
|
//
|
|
// This file is part of ProtonMail Bridge.Bridge.
|
|
//
|
|
// ProtonMail Bridge is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// ProtonMail Bridge is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with ProtonMail Bridge. If not, see <https://www.gnu.org/licenses/>.
|
|
|
|
package pmapi
|
|
|
|
import (
|
|
"crypto/sha256"
|
|
"crypto/tls"
|
|
"crypto/x509"
|
|
"encoding/base64"
|
|
"errors"
|
|
"fmt"
|
|
"net"
|
|
)
|
|
|
|
// ErrTLSMismatch indicates that no TLS fingerprint match could be found.
|
|
var ErrTLSMismatch = errors.New("no TLS fingerprint match found")
|
|
|
|
type pinChecker struct {
|
|
trustedPins []string
|
|
}
|
|
|
|
func newPinChecker(trustedPins []string) *pinChecker {
|
|
return &pinChecker{
|
|
trustedPins: trustedPins,
|
|
}
|
|
}
|
|
|
|
// checkCertificate returns whether the connection presents a known TLS certificate.
|
|
func (p *pinChecker) checkCertificate(conn net.Conn) error {
|
|
tlsConn, ok := conn.(*tls.Conn)
|
|
if !ok {
|
|
return errors.New("connection is not a TLS connection")
|
|
}
|
|
|
|
connState := tlsConn.ConnectionState()
|
|
|
|
for _, peerCert := range connState.PeerCertificates {
|
|
fingerprint := certFingerprint(peerCert)
|
|
|
|
for _, pin := range p.trustedPins {
|
|
if pin == fingerprint {
|
|
return nil
|
|
}
|
|
}
|
|
}
|
|
|
|
return ErrTLSMismatch
|
|
}
|
|
|
|
func certFingerprint(cert *x509.Certificate) string {
|
|
hash := sha256.Sum256(cert.RawSubjectPublicKeyInfo)
|
|
return fmt.Sprintf(`pin-sha256=%q`, base64.StdEncoding.EncodeToString(hash[:]))
|
|
}
|