/*
 * Copyright (c) 2000 Markus Friedl.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * $OpenBSD: auth.h,v 1.11 2001/02/12 16:16:23 markus Exp $
 */
#ifndef AUTH_H
#define AUTH_H

#include <openssl/rsa.h>

typedef struct Authctxt Authctxt;
struct Authctxt {
	int success;
	int postponed;
	int valid;
	int attempt;
	int failures;
	char *user;
	char *service;
	struct passwd *pw;
	char *style;
};

/*
 * Tries to authenticate the user using the .rhosts file.  Returns true if
 * authentication succeeds.  If ignore_rhosts is non-zero, this will not
 * consider .rhosts and .shosts (/etc/hosts.equiv will still be used).
 */
int     auth_rhosts(struct passwd * pw, const char *client_user);

/*
 * Tries to authenticate the user using the .rhosts file and the host using
 * its host key.  Returns true if authentication succeeds.
 */
int
auth_rhosts_rsa(struct passwd * pw, const char *client_user, RSA* client_host_key);

/*
 * Tries to authenticate the user using password.  Returns true if
 * authentication succeeds.
 */
int     auth_password(struct passwd * pw, const char *password);

/*
 * Performs the RSA authentication dialog with the client.  This returns 0 if
 * the client could not be authenticated, and 1 if authentication was
 * successful.  This may exit if there is a serious protocol violation.
 */
int     auth_rsa(struct passwd * pw, BIGNUM * client_n);

/*
 * Parses an RSA key (number of bits, e, n) from a string.  Moves the pointer
 * over the key.  Skips any whitespace at the beginning and at end.
 */
int     auth_rsa_read_key(char **cpp, u_int *bitsp, BIGNUM * e, BIGNUM * n);

/*
 * Performs the RSA authentication challenge-response dialog with the client,
 * and returns true (non-zero) if the client gave the correct answer to our
 * challenge; returns zero if the client gives a wrong answer.
 */
int     auth_rsa_challenge_dialog(RSA *pk);

#ifdef KRB5
#include <krb5.h>
int	auth_krb5(const char* server_user, krb5_data *auth,
		  krb5_principal *client);
int	auth_krb5_tgt(char *server_user, krb5_data *tgt,
		      krb5_principal tkt_client);
int	krb5_init(void);
void	krb5_cleanup_proc(void *ignore);
int	auth_krb5_password(struct passwd *pw, const char *password);
void	send_krb5_tgt(krb5_context context, krb5_auth_context auth_context);
int	try_krb5_authentication(krb5_context *context, krb5_auth_context *auth_context);
#endif /* KRB5 */

#ifdef KRB4
#include <krb.h>
/*
 * Performs Kerberos v4 mutual authentication with the client. This returns 0
 * if the client could not be authenticated, and 1 if authentication was
 * successful.  This may exit if there is a serious protocol violation.
 */
int     auth_krb4(const char *server_user, KTEXT auth, char **client);
int     krb4_init(uid_t uid);
void    krb4_cleanup_proc(void *ignore);
int	auth_krb4_password(struct passwd * pw, const char *password);
int	send_krb4_tgt(void);

#ifdef AFS
#include <kafs.h>

/* Accept passed Kerberos v4 ticket-granting ticket and AFS tokens. */
int     auth_krb4_tgt(struct passwd * pw, const char *string);
int     auth_afs_token(struct passwd * pw, const char *token_string);

int	creds_to_radix(CREDENTIALS *creds, u_char *buf, size_t buflen);
int	radix_to_creds(const char *buf, CREDENTIALS *creds);
void	send_afs_tokens(void);

#endif				/* AFS */

#endif				/* KRB4 */

void	do_authentication(void);
void	do_authentication2(void);

Authctxt *authctxt_new(void);
void	auth_log(Authctxt *authctxt, int authenticated, char *method, char *info);
void	userauth_reply(Authctxt *authctxt, int authenticated);
int	auth_root_allowed(char *method);

int	auth2_challenge(Authctxt *authctxt, char *devs);

int	allowed_user(struct passwd * pw);

char	*get_challenge(Authctxt *authctxt, char *devs);
int	verify_response(Authctxt *authctxt, char *response);

struct passwd * auth_get_user(void);
struct passwd * pwcopy(struct passwd *pw);

#define AUTH_FAIL_MAX 6
#define AUTH_FAIL_LOG (AUTH_FAIL_MAX/2)
#define AUTH_FAIL_MSG "Too many authentication failures for %.100s"

#endif