source: code/trunk/vendor/github.com/emersion/go-sasl/anonymous.go@ 822

package sasl

// The ANONYMOUS mechanism name.
const Anonymous = "ANONYMOUS"

type anonymousClient struct {
        Trace string
}

func (c *anonymousClient) Start() (mech string, ir []byte, err error) {
        mech = Anonymous
        ir = []byte(c.Trace)
        return
}

func (c *anonymousClient) Next(challenge []byte) (response []byte, err error) {
        return nil, ErrUnexpectedServerChallenge
}

// A client implementation of the ANONYMOUS authentication mechanism, as
// described in RFC 4505.
func NewAnonymousClient(trace string) Client {
        return &anonymousClient{trace}
}

// Get trace information from clients logging in anonymously.
type AnonymousAuthenticator func(trace string) error

type anonymousServer struct {
        done         bool
        authenticate AnonymousAuthenticator
}

func (s *anonymousServer) Next(response []byte) (challenge []byte, done bool, err error) {
        if s.done {
                err = ErrUnexpectedClientResponse
                return
        }

        // No initial response, send an empty challenge
        if response == nil {
                return []byte{}, false, nil
        }

        s.done = true

        err = s.authenticate(string(response))
        done = true
        return
}

// A server implementation of the ANONYMOUS authentication mechanism, as
// described in RFC 4505.
func NewAnonymousServer(authenticator AnonymousAuthenticator) Server {
        return &anonymousServer{authenticate: authenticator}
}