go-mail/smtp/auth_cram_md5.go
Winni Neessen 0d6777ab39
Fork net/smpt into go-mail
As part of #97 we are going to fork the official `net/smtp` package into go-mail to provide us with more flexibility.

This commit fulfills the first big step of importing the package into smtp/. Also go-mail's own LoginAuth has been moved from auth/ into smtp/ to be consistent with the stdlib.

There are still a couple of open issues (i. e. license adjustments and making golangci-lint happy) but so far all tests already work, which is a good start.
2023-01-10 00:38:42 +01:00

34 lines
912 B
Go

package smtp
import (
"crypto/hmac"
"crypto/md5"
"fmt"
)
// cramMD5Auth is the type that satisfies the Auth interface for the "SMTP CRAM_MD5" auth
type cramMD5Auth struct {
username, secret string
}
// CRAMMD5Auth returns an Auth that implements the CRAM-MD5 authentication
// mechanism as defined in RFC 2195.
// The returned Auth uses the given username and secret to authenticate
// to the server using the challenge-response mechanism.
func CRAMMD5Auth(username, secret string) Auth {
return &cramMD5Auth{username, secret}
}
func (a *cramMD5Auth) Start(server *ServerInfo) (string, []byte, error) {
return "CRAM-MD5", nil, nil
}
func (a *cramMD5Auth) Next(fromServer []byte, more bool) ([]byte, error) {
if more {
d := hmac.New(md5.New, []byte(a.secret))
d.Write(fromServer)
s := make([]byte, 0, d.Size())
return fmt.Appendf(nil, "%s %x", a.username, d.Sum(s)), nil
}
return nil, nil
}