status-go/vendor/github.com/anacrolix/missinggo/tls.go

33 lines
786 B
Go

package missinggo
import (
"crypto/tls"
"strings"
)
// Select the best named certificate per the usual behaviour if
// c.GetCertificate is nil, and c.NameToCertificate is not.
func BestNamedCertificate(c *tls.Config, clientHello *tls.ClientHelloInfo) (*tls.Certificate, bool) {
name := strings.ToLower(clientHello.ServerName)
for len(name) > 0 && name[len(name)-1] == '.' {
name = name[:len(name)-1]
}
if cert, ok := c.NameToCertificate[name]; ok {
return cert, true
}
// try replacing labels in the name with wildcards until we get a
// match.
labels := strings.Split(name, ".")
for i := range labels {
labels[i] = "*"
candidate := strings.Join(labels, ".")
if cert, ok := c.NameToCertificate[candidate]; ok {
return cert, true
}
}
return nil, false
}