blob: 7fef1990c56697701a9b934799298c4aa0296d26 [file] [log] [blame]
// +build !appengine
/*
*
* Copyright 2020 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package advancedtls
import (
"crypto/tls"
"fmt"
)
// buildGetCertificates returns the certificate that matches the SNI field
// for the given ClientHelloInfo, defaulting to the first element of o.GetCertificates.
func buildGetCertificates(clientHello *tls.ClientHelloInfo, o *ServerOptions) (*tls.Certificate, error) {
if o.IdentityOptions.GetIdentityCertificatesForServer == nil {
return nil, fmt.Errorf("function GetCertificates must be specified")
}
certificates, err := o.IdentityOptions.GetIdentityCertificatesForServer(clientHello)
if err != nil {
return nil, err
}
if len(certificates) == 0 {
return nil, fmt.Errorf("no certificates configured")
}
// If users pass in only one certificate, return that certificate.
if len(certificates) == 1 {
return certificates[0], nil
}
// Choose the SNI certificate using SupportsCertificate.
for _, cert := range certificates {
if err := clientHello.SupportsCertificate(cert); err == nil {
return cert, nil
}
}
// If nothing matches, return the first certificate.
return certificates[0], nil
}