func (ks *Keyserver) verifyUpdateEdge(req *proto.UpdateRequest) error {
if len(req.Update.NewEntry.Index) != vrf.Size {
return fmt.Errorf("index '%x' has wrong length (expected %d)", req.Update.NewEntry.Index, vrf.Size)
}
prevUpdate, err := ks.getUpdate(req.Update.NewEntry.Index, math.MaxUint64)
if err != nil {
log.Print(err)
return fmt.Errorf("internal error")
}
if prevUpdate == nil { // registration: check email proof
if !ks.insecureSkipEmailProof {
email, payload, err := dkim.CheckEmailProof(req.DKIMProof, ks.emailProofToAddr,
ks.emailProofSubjectPrefix, ks.lookupTXT, ks.clk.Now)
if err != nil {
return fmt.Errorf("failed to verify DKIM proof: %s", err)
}
if got, want := email, req.LookupParameters.UserId; got != want {
return fmt.Errorf("requested user ID does not match the email proof: %q != %q", got, want)
}
lastAtIndex := strings.LastIndex(req.LookupParameters.UserId, "@")
if lastAtIndex == -1 {
return fmt.Errorf("requested user id is not a valid email address: %q", req.LookupParameters.UserId)
}
if _, ok := ks.emailProofAllowedDomains[req.LookupParameters.UserId[lastAtIndex+1:]]; !ok {
return fmt.Errorf("domain not in registration whitelist: %q", req.LookupParameters.UserId[lastAtIndex+1:])
}
entryHash, err := base64.StdEncoding.DecodeString(payload)
if err != nil {
return fmt.Errorf("bad base64 in email proof: %q", payload)
}
var entryHashProposed [32]byte
sha3.ShakeSum256(entryHashProposed[:], req.Update.NewEntry.Encoding)
if !bytes.Equal(entryHashProposed[:], entryHash[:]) {
return fmt.Errorf("email proof does not match requested entry: %s vs %s (%x)", base64.StdEncoding.EncodeToString(entryHashProposed[:]), payload, req.Update.NewEntry.Encoding)
}
}
}
return ks.verifyUpdateDeterministic(prevUpdate, req)
}
func (ks *Keyserver) verifyUpdateEdge(req *proto.UpdateRequest) error {
if len(req.Update.NewEntry.Index) != vrf.Size {
return fmt.Errorf("index '%x' has wrong length (expected %d)", req.Update.NewEntry.Index, vrf.Size)
}
prevUpdate, err := ks.getUpdate(req.Update.NewEntry.Index, math.MaxUint64)
if err != nil {
log.Print(err)
return fmt.Errorf("internal error")
}
if prevUpdate == nil { // registration: check email proof
if !ks.insecureSkipEmailProof {
if req.EmailProof == nil {
return fmt.Errorf("No email proof provided")
}
lastAtIndex := strings.LastIndex(req.LookupParameters.UserId, "@")
if lastAtIndex == -1 {
return fmt.Errorf("requested user id is not a valid email address: %q", req.LookupParameters.UserId)
}
// determine registration type
switch t := req.EmailProof.ProofType.(type) {
case *proto.EmailProof_DKIMProof:
if _, ok := ks.dkimProofAllowedDomains[req.LookupParameters.UserId[lastAtIndex+1:]]; !ok {
return fmt.Errorf("domain not in registration whitelist: %q", req.LookupParameters.UserId[lastAtIndex+1:])
}
email, payload, err := dkim.CheckEmailProof(t.DKIMProof, ks.dkimProofToAddr, ks.dkimProofToAddr, ks.lookupTXT, ks.clk.Now)
if err != nil {
return fmt.Errorf("failed to verify DKIM proof: %s", err)
}
if got, want := email, req.LookupParameters.UserId; got != want {
return fmt.Errorf("requested user ID does not match the email proof: %q != %q", got, want)
}
entryHash, err := base64.StdEncoding.DecodeString(payload)
if err != nil {
return fmt.Errorf("bad base64 in email proof: %q", payload)
}
var entryHashProposed [32]byte
sha3.ShakeSum256(entryHashProposed[:], req.Update.NewEntry.Encoding)
if !bytes.Equal(entryHashProposed[:], entryHash[:]) {
return fmt.Errorf("email proof does not match requested entry: %s vs %s (%x)", base64.StdEncoding.EncodeToString(entryHashProposed[:]), payload, req.Update.NewEntry.Encoding)
}
case *proto.EmailProof_OIDCToken:
found := false
for _, oc := range ks.oidcProofConfig {
if _, ok := oc.allowedDomains[req.LookupParameters.UserId[lastAtIndex+1:]]; !ok {
continue
}
found = true
email, err := oc.oidcClient.VerifyIDToken(t.OIDCToken)
if err != nil {
if _, ok := err.(*oidc.ErrExpired); ok {
return &errExpired{err: err}
}
return err
}
if got, want := email, req.LookupParameters.UserId; got != want {
return fmt.Errorf("requested user ID does not match the email proof: %q != %q", got, want)
}
}
if !found {
return fmt.Errorf("domain not in registration whitelist: %q", req.LookupParameters.UserId[lastAtIndex+1:])
}
case *proto.EmailProof_SAMLResponse:
if _, ok := ks.samlProofAllowedDomains[req.LookupParameters.UserId[lastAtIndex+1:]]; !ok {
return fmt.Errorf("domain not in registration whitelist: %q", req.LookupParameters.UserId[lastAtIndex+1:])
}
email, err := saml.VerifySAMLResponse(t.SAMLResponse, ks.samlProofIDPCert, ks.samlProofConsumerServiceURL, "EmailAddress", ks.samlProofValidity)
if err != nil {
if _, ok := err.(*saml.ErrExpired); ok {
return &errExpired{err: err}
}
return err
}
if got, want := email, req.LookupParameters.UserId; got != want {
return fmt.Errorf("requested user ID does not match the email proof: %q != %q", got, want)
}
default:
return fmt.Errorf("Invalid email proof type: %T", t)
}
}
}
return ks.verifyUpdateDeterministic(prevUpdate, req)
}