/*
 * This file is part of the SSH Library
 *
 * Copyright (c) 2008-2009 Andreas Schneider <asn@cryptomilk.org>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef __AGENT_H
#define __AGENT_H

#include "libssh/libssh.h"

/* Messages for the authentication agent connection. */
#define SSH_AGENTC_REQUEST_RSA_IDENTITIES        1
#define SSH_AGENT_RSA_IDENTITIES_ANSWER          2
#define SSH_AGENTC_RSA_CHALLENGE                 3
#define SSH_AGENT_RSA_RESPONSE                   4
#define SSH_AGENT_FAILURE                        5
#define SSH_AGENT_SUCCESS                        6
#define SSH_AGENTC_ADD_RSA_IDENTITY              7
#define SSH_AGENTC_REMOVE_RSA_IDENTITY           8
#define SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES     9

/* private OpenSSH extensions for SSH2 */
#define SSH2_AGENTC_REQUEST_IDENTITIES           11
#define SSH2_AGENT_IDENTITIES_ANSWER             12
#define SSH2_AGENTC_SIGN_REQUEST                 13
#define SSH2_AGENT_SIGN_RESPONSE                 14
#define SSH2_AGENTC_ADD_IDENTITY                 17
#define SSH2_AGENTC_REMOVE_IDENTITY              18
#define SSH2_AGENTC_REMOVE_ALL_IDENTITIES        19

/* smartcard */
#define SSH_AGENTC_ADD_SMARTCARD_KEY             20
#define SSH_AGENTC_REMOVE_SMARTCARD_KEY          21

/* lock/unlock the agent */
#define SSH_AGENTC_LOCK                          22
#define SSH_AGENTC_UNLOCK                        23

/* add key with constraints */
#define SSH_AGENTC_ADD_RSA_ID_CONSTRAINED        24
#define SSH2_AGENTC_ADD_ID_CONSTRAINED           25
#define SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED 26

#define SSH_AGENT_CONSTRAIN_LIFETIME             1
#define SSH_AGENT_CONSTRAIN_CONFIRM              2

/* extended failure messages */
#define SSH2_AGENT_FAILURE                       30

/* additional error code for ssh.com's ssh-agent2 */
#define SSH_COM_AGENT2_FAILURE                   102

#define SSH_AGENT_OLD_SIGNATURE                  0x01
/* Signature flags from draft-miller-ssh-agent-02 */
#define SSH_AGENT_RSA_SHA2_256                   0x02
#define SSH_AGENT_RSA_SHA2_512                   0x04

struct ssh_agent_struct {
  struct ssh_socket_struct *sock;
  ssh_buffer ident;
  unsigned int count;
  ssh_channel channel;
};

/* agent.c */
/**
 * @brief Create a new ssh agent structure.
 *
 * @return An allocated ssh agent structure or NULL on error.
 */
struct ssh_agent_struct *ssh_agent_new(struct ssh_session_struct *session);

void ssh_agent_close(struct ssh_agent_struct *agent);

/**
 * @brief Free an allocated ssh agent structure.
 *
 * @param agent The ssh agent structure to free.
 */
void ssh_agent_free(struct ssh_agent_struct *agent);

/**
 * @brief Check if the ssh agent is running.
 *
 * @param session The ssh session to check for the agent.
 *
 * @return 1 if it is running, 0 if not.
 */
int ssh_agent_is_running(struct ssh_session_struct *session);

uint32_t ssh_agent_get_ident_count(struct ssh_session_struct *session);

ssh_key ssh_agent_get_next_ident(struct ssh_session_struct *session,
                                 char **comment);

ssh_key ssh_agent_get_first_ident(struct ssh_session_struct *session,
                                  char **comment);

ssh_string ssh_agent_sign_data(ssh_session session,
                               const ssh_key pubkey,
                               struct ssh_buffer_struct *data);

#endif /* __AGENT_H */
