/*

  protocol.h

  Author: Pekka Riikonen <priikone@poseidon.pspt.fi>

  Copyright (C) 1997 - 2000 Pekka Riikonen

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.
  
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

*/

#ifndef PROTOCOL_H
#define PROTOCOL_H

/* SILC client protocol types */
#define SILC_PROTOCOL_CLIENT_NONE               0
#define SILC_PROTOCOL_CLIENT_CONNECTION_AUTH    1
#define SILC_PROTOCOL_CLIENT_KEY_EXCHANGE       2
#define SILC_PROTOCOL_CLIENT_REKEY              3
/* #define SILC_PROTOCOL_CLIENT_MAX             255 */

/* Internal context for key exchange protocol */
typedef struct {
  void *client;
  SilcSocketConnection sock;
  SilcRng rng;
  int responder;

  void *dest_id;		    /* Destination ID from packet */
  SilcIdType dest_id_type;	    /* Destination ID type */

  SilcTask timeout_task;
  SilcPacketContext *packet;

  SilcSKESendPacketCb send_packet;  /* SKE's packet sending callback */
  SilcSKEVerifyCb verify;	    /* SKE's key verify callback */
  SilcSKE ske;			    /* The SKE object */
  SilcSKEKeyMaterial *keymat;	    /* The negotiated key material */
  void *context;		    /* Internal context */
} SilcClientKEInternalContext;

/* Internal context for connection authentication protocol */
typedef struct {
  void *client;
  SilcSocketConnection sock;

  /* SKE object from Key Exchange protocol. */
  SilcSKE ske;

  /* Auth method that must be used. This is resolved before this
     connection authentication protocol is started. */
  SilcProtocolAuthMeth auth_meth;

  /* Destinations ID from KE protocol context */
  void *dest_id;
  SilcIdType dest_id_type;

  /* Authentication data if we alreay know it. This is filled before
     starting the protocol if we know the authentication data. Otherwise
     these are and remain NULL. */
  unsigned char *auth_data;
  SilcUInt32 auth_data_len;

  SilcTask timeout_task;
} SilcClientConnAuthInternalContext;

/* Internal context for the rekey protocol */
typedef struct {
  void *client;
  void *context;
  SilcSocketConnection sock;
  bool responder;		    /* TRUE if we are receiving party */
  bool pfs;			    /* TRUE if PFS is to be used */
  SilcSKE ske;			    /* Defined if PFS is used */
  SilcPacketContext *packet;
} SilcClientRekeyInternalContext;

/* Prototypes */
void silc_client_protocols_register(void);
void silc_client_protocols_unregister(void);
void silc_client_protocol_ke_send_packet(SilcSKE ske,
					 SilcBuffer packet,
					 SilcPacketType type,
					 void *context);
void silc_client_protocol_ke_verify_key(SilcSKE ske,
					unsigned char *pk_data,
					SilcUInt32 pk_len,
					SilcSKEPKType pk_type,
					void *context,
					SilcSKEVerifyCbCompletion completion,
					void *completion_context);
void silc_client_protocol_ke_set_keys(SilcSKE ske,
				      SilcSocketConnection sock,
				      SilcSKEKeyMaterial *keymat,
				      SilcCipher cipher,
				      SilcPKCS pkcs,
				      SilcHash hash,
				      SilcHmac hmac,
				      SilcSKEDiffieHellmanGroup group,
				      bool is_responder);

#endif