func getGRPCConnection(creds credentials.TransportCredentials, r remotes.Remotes) (*grpc.ClientConn, api.Peer, error) {
peer, err := r.Select()
if err != nil {
return nil, api.Peer{}, err
}
opts := []grpc.DialOption{
grpc.WithTransportCredentials(creds),
grpc.WithTimeout(5 * time.Second),
grpc.WithBackoffMaxDelay(5 * time.Second),
}
conn, err := grpc.Dial(peer.Addr, opts...)
if err != nil {
return nil, api.Peer{}, err
}
return conn, peer, nil
}
// GetRemoteSignedCertificate submits a CSR to a remote CA server address,
// and that is part of a CA identified by a specific certificate pool.
func GetRemoteSignedCertificate(ctx context.Context, csr []byte, token string, rootCAPool *x509.CertPool, r remotes.Remotes, creds credentials.TransportCredentials, nodeInfo chan<- api.IssueNodeCertificateResponse) ([]byte, error) {
if rootCAPool == nil {
return nil, errors.New("valid root CA pool required")
}
if creds == nil {
// This is our only non-MTLS request, and it happens when we are boostraping our TLS certs
// We're using CARole as server name, so an external CA doesn't also have to have ManagerRole in the cert SANs
creds = credentials.NewTLS(&tls.Config{ServerName: CARole, RootCAs: rootCAPool})
}
peer, err := r.Select()
if err != nil {
return nil, err
}
opts := []grpc.DialOption{
grpc.WithTransportCredentials(creds),
grpc.WithTimeout(5 * time.Second),
grpc.WithBackoffMaxDelay(5 * time.Second),
}
conn, err := grpc.Dial(peer.Addr, opts...)
if err != nil {
return nil, err
}
defer conn.Close()
// Create a CAClient to retrieve a new Certificate
caClient := api.NewNodeCAClient(conn)
// Send the Request and retrieve the request token
issueRequest := &api.IssueNodeCertificateRequest{CSR: csr, Token: token}
issueResponse, err := caClient.IssueNodeCertificate(ctx, issueRequest)
if err != nil {
return nil, err
}
// Send back the NodeID on the nodeInfo, so the caller can know what ID was assigned by the CA
if nodeInfo != nil {
nodeInfo <- *issueResponse
}
statusRequest := &api.NodeCertificateStatusRequest{NodeID: issueResponse.NodeID}
expBackoff := events.NewExponentialBackoff(events.ExponentialBackoffConfig{
Base: time.Second,
Factor: time.Second,
Max: 30 * time.Second,
})
// Exponential backoff with Max of 30 seconds to wait for a new retry
for {
// Send the Request and retrieve the certificate
ctx, cancel := context.WithTimeout(ctx, 5*time.Second)
defer cancel()
statusResponse, err := caClient.NodeCertificateStatus(ctx, statusRequest)
if err != nil {
r.Observe(peer, -remotes.DefaultObservationWeight)
return nil, err
}
// If the certificate was issued, return
if statusResponse.Status.State == api.IssuanceStateIssued {
if statusResponse.Certificate == nil {
return nil, errors.New("no certificate in CertificateStatus response")
}
// The certificate in the response must match the CSR
// we submitted. If we are getting a response for a
// certificate that was previously issued, we need to
// retry until the certificate gets updated per our
// current request.
if bytes.Equal(statusResponse.Certificate.CSR, csr) {
r.Observe(peer, remotes.DefaultObservationWeight)
return statusResponse.Certificate.Certificate, nil
}
}
// If we're still pending, the issuance failed, or the state is unknown
// let's continue trying.
expBackoff.Failure(nil, nil)
time.Sleep(expBackoff.Proceed(nil))
}
}
// GetRemoteCA returns the remote endpoint's CA certificate
func GetRemoteCA(ctx context.Context, d digest.Digest, r remotes.Remotes) (RootCA, error) {
// This TLS Config is intentionally using InsecureSkipVerify. Either we're
// doing TOFU, in which case we don't validate the remote CA, or we're using
// a user supplied hash to check the integrity of the CA certificate.
insecureCreds := credentials.NewTLS(&tls.Config{InsecureSkipVerify: true})
opts := []grpc.DialOption{
grpc.WithTransportCredentials(insecureCreds),
grpc.WithTimeout(5 * time.Second),
grpc.WithBackoffMaxDelay(5 * time.Second),
}
peer, err := r.Select()
if err != nil {
return RootCA{}, err
}
conn, err := grpc.Dial(peer.Addr, opts...)
if err != nil {
return RootCA{}, err
}
defer conn.Close()
client := api.NewCAClient(conn)
ctx, cancel := context.WithTimeout(ctx, 5*time.Second)
defer cancel()
defer func() {
if err != nil {
r.Observe(peer, -remotes.DefaultObservationWeight)
return
}
r.Observe(peer, remotes.DefaultObservationWeight)
}()
response, err := client.GetRootCACertificate(ctx, &api.GetRootCACertificateRequest{})
if err != nil {
return RootCA{}, err
}
if d != "" {
verifier, err := digest.NewDigestVerifier(d)
if err != nil {
return RootCA{}, errors.Wrap(err, "unexpected error getting digest verifier")
}
io.Copy(verifier, bytes.NewReader(response.Certificate))
if !verifier.Verified() {
return RootCA{}, errors.Errorf("remote CA does not match fingerprint. Expected: %s", d.Hex())
}
}
// Check the validity of the remote Cert
_, err = helpers.ParseCertificatePEM(response.Certificate)
if err != nil {
return RootCA{}, err
}
// Create a Pool with our RootCACertificate
pool := x509.NewCertPool()
if !pool.AppendCertsFromPEM(response.Certificate) {
return RootCA{}, errors.New("failed to append certificate to cert pool")
}
return RootCA{Cert: response.Certificate, Digest: digest.FromBytes(response.Certificate), Pool: pool}, nil
}