syntax = "proto3";

/*
 * Client message to the server.  Messages on the wire are
 * prefixed with a 32-bit size in network byte order.
 */
message ClientMessage {
  oneof type {
    AcceptMessage accept_msg = 1;
    RejectMessage reject_msg = 2;
    ExitMessage exit_msg = 3;
    RestartMessage restart_msg = 4;
    AlertMessage alert_msg = 5;
    IoBuffer ttyin_buf = 6;
    IoBuffer ttyout_buf = 7;
    IoBuffer stdin_buf = 8;
    IoBuffer stdout_buf = 9;
    IoBuffer stderr_buf = 10;
    ChangeWindowSize winsize_event = 11;
    CommandSuspend suspend_event = 12;
    ClientHello hello_msg = 13;
  }
}

/* Equivalent of POSIX struct timespec */
message TimeSpec {
    int64 tv_sec = 1;		/* seconds */
    int32 tv_nsec = 2;		/* nanoseconds */
}

/* I/O buffer with keystroke data */
message IoBuffer {
  TimeSpec delay = 1;		/* elapsed time since last record */
  bytes data = 2;		/* keystroke data */
}

/*
 * Key/value pairs, like Privilege Manager struct info.
 * The value may be a number, a string, or a list of strings.
 */
message InfoMessage {
  message StringList {
    repeated string strings = 1;
  }
  message NumberList {
    repeated int64 numbers = 1;
  }
  string key = 1;
  oneof value {
    int64 numval = 2;
    string strval = 3;
    StringList strlistval = 4;
    NumberList numlistval = 5;
  }
}

/*
 * Event log data for command accepted by the policy.
 */
message AcceptMessage {
  TimeSpec submit_time = 1;		/* when command was submitted */
  repeated InfoMessage info_msgs = 2;	/* key,value event log data */
  bool expect_iobufs = 3;		/* true if I/O logging enabled */
}

/*
 * Event log data for command rejected by the policy.
 */
message RejectMessage {
  TimeSpec submit_time = 1;		/* when command was submitted */
  string reason = 2;			/* reason command was rejected */
  repeated InfoMessage info_msgs = 3;	/* key,value event log data */
}

/* Message sent by client when command exits. */
/* Might revisit runtime and use end_time instead */
message ExitMessage {
  TimeSpec run_time = 1;	/* total elapsed run time */
  int32 exit_value = 2;		/* 0-255 */
  bool dumped_core = 3;		/* true if command dumped core */
  string signal = 4;		/* signal name if killed by signal */
  string error = 5;		/* if killed due to other error */
}

/* Alert message, policy module-specific. */
message AlertMessage {
  TimeSpec alert_time = 1;		/* time alert message occurred */
  string reason = 2;			/* policy alert error string */
  repeated InfoMessage info_msgs = 3;	/* optional key,value event log data */
}

/* Used to restart an existing I/O log on the server. */
message RestartMessage {
  string log_id = 1;		/* ID of log being restarted */
  TimeSpec resume_point = 2;	/* resume point (elapsed time) */
}

/* Window size change event. */
message ChangeWindowSize {
  TimeSpec delay = 1;		/* elapsed time since last record */
  int32 rows = 2;		/* new number of rows */
  int32 cols = 3;		/* new number of columns */
}

/* Command suspend/resume event. */
message CommandSuspend {
  TimeSpec delay = 1;		/* elapsed time since last record */
  string signal = 2;		/* signal that caused suspend/resume */
}

/* Hello message from client when connecting to server. */
message ClientHello {
  string client_id = 1;		/* free-form client description */
}

/*
 * Server messages to the client.  Messages on the wire are
 * prefixed with a 32-bit size in network byte order.
 */
message ServerMessage {
  oneof type {
    ServerHello hello = 1;	/* server hello message */
    TimeSpec commit_point = 2;	/* cumulative time of records stored */
    string log_id = 3;		/* ID of server-side I/O log */
    string error = 4;		/* error message from server */
    string abort = 5;		/* abort message, kill command */
  }
}

/* Hello message from server when client connects. */
message ServerHello {
  string server_id = 1;		/* free-form server description */
  string redirect = 2;		/* optional redirect if busy */
  repeated string servers = 3;	/* optional list of known servers */
  bool subcommands = 4;		/* flag: server supports sub-commands */
}