syntax = "proto3";

package connectca;

import "google/protobuf/timestamp.proto";

service ConnectCAService {
  // WatchRoots provides a stream on which you can receive the list of active
  // Connect CA roots. Current roots are sent immediately at the start of the
  // stream, and new lists will be sent whenever the roots are rotated.
  rpc WatchRoots(WatchRootsRequest) returns (stream WatchRootsResponse) {}

  // Sign a leaf certificate for the service or agent identified by the SPIFFE
  // ID in the given CSR's SAN.
  rpc Sign(SignRequest) returns (SignResponse) {}
}

message WatchRootsRequest {}

message WatchRootsResponse {
  // active_root_id is the ID of a root in Roots that is the active CA root.
  // Other roots are still valid if they're in the Roots list but are in the
  // process of being rotated out.
  string active_root_id = 1;

  // trust_domain is the identification root for this Consul cluster. All
  // certificates signed by the cluster's CA must have their identifying URI
  // in this domain.
  //
  // This does not include the protocol (currently spiffe://) since we may
  // implement other protocols in future with equivalent semantics. It should
  // be compared against the "authority" section of a URI (i.e. host:port).
  string trust_domain = 2;

  // roots is a list of root CA certs to trust.
  repeated CARoot roots = 3;
}

message CARoot {
  // id is a globally unique ID (UUID) representing this CA root.
  string id = 1;

  // name is a human-friendly name for this CA root. This value is opaque to
  // Consul and is not used for anything internally.
  string name = 2;

  // serial_number is the x509 serial number of the certificate.
  uint64 serial_number = 3;

  // signing_key_id is the connect.HexString encoded id of the public key that
  // corresponds to the private key used to sign leaf certificates in the
  // local datacenter.
  //
  // The value comes from x509.Certificate.SubjectKeyId of the local leaf
  // signing cert.
  //
  // See https://www.rfc-editor.org/rfc/rfc3280#section-4.2.1.1 for more detail.
  string signing_key_id = 4;

  // root_cert is the PEM-encoded public certificate.
  string root_cert = 5;

  // intermediate_certs is a list of PEM-encoded intermediate certs to
  // attach to any leaf certs signed by this CA.
  repeated string intermediate_certs = 6;

  // active is true if this is the current active CA. This must only
  // be true for exactly one CA.
  bool active = 7;

  // rotated_out_at is the time at which this CA was removed from the state.
  // This will only be set on roots that have been rotated out from being the
  // active root.
  google.protobuf.Timestamp rotated_out_at = 8;
}

message SignRequest {
  // csr is the PEM-encoded Certificate Signing Request (CSR).
  //
  // The CSR's SAN must include a SPIFFE ID that identifies a service or agent
  // to which the ACL token provided in the `x-consul-token` metadata has write
  // access.
  string csr = 1;
}

message SignResponse {
  // cert_pem is the PEM-encoded leaf certificate.
  string cert_pem = 2;
}