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/* $OpenBSD: auth.h,v 1.48 2003/11/04 08:54:09 djm Exp $ */
/*
* 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.
*
*/
#ifndef AUTH_H
#define AUTH_H
#include "key.h"
#include "hostfile.h"
#include <openssl/rsa.h>
#ifdef HAVE_LOGIN_CAP
#include <login_cap.h>
#endif
#ifdef BSD_AUTH
#include <bsd_auth.h>
#endif
#ifdef KRB5
#include <krb5.h>
#endif
typedef struct Authctxt Authctxt;
typedef struct Authmethod Authmethod;
typedef struct KbdintDevice KbdintDevice;
struct Authctxt {
int success;
int postponed; /* authentication needs another step */
int valid; /* user exists and is allowed to login */
int attempt;
int failures;
char *user; /* username sent by the client */
char *service;
struct passwd *pw; /* set if 'valid' */
char *style;
void *kbdintctxt;
#ifdef BSD_AUTH
auth_session_t *as;
#endif
#ifdef KRB5
krb5_context krb5_ctx;
krb5_ccache krb5_fwd_ccache;
krb5_principal krb5_user;
char *krb5_ticket_file;
#endif
void *methoddata;
};
/*
* Every authentication method has to handle authentication requests for
* non-existing users, or for users that are not allowed to login. In this
* case 'valid' is set to 0, but 'user' points to the username requested by
* the client.
*/
struct Authmethod {
char *name;
int (*userauth)(Authctxt *authctxt);
int *enabled;
};
/*
* Keyboard interactive device:
* init_ctx returns: non NULL upon success
* query returns: 0 - success, otherwise failure
* respond returns: 0 - success, 1 - need further interaction,
* otherwise - failure
*/
struct KbdintDevice
{
const char *name;
void* (*init_ctx)(Authctxt*);
int (*query)(void *ctx, char **name, char **infotxt,
u_int *numprompts, char ***prompts, u_int **echo_on);
int (*respond)(void *ctx, u_int numresp, char **responses);
void (*free_ctx)(void *ctx);
};
int auth_rhosts(struct passwd *, const char *);
int
auth_rhosts2(struct passwd *, const char *, const char *, const char *);
int auth_rhosts_rsa(Authctxt *, char *, Key *);
int auth_password(Authctxt *, const char *);
int auth_rsa(Authctxt *, BIGNUM *);
int auth_rsa_challenge_dialog(Key *);
BIGNUM *auth_rsa_generate_challenge(Key *);
int auth_rsa_verify_response(Key *, BIGNUM *, u_char[]);
int auth_rsa_key_allowed(struct passwd *, BIGNUM *, Key **);
int auth_rhosts_rsa_key_allowed(struct passwd *, char *, char *, Key *);
int hostbased_key_allowed(struct passwd *, const char *, char *, Key *);
int user_key_allowed(struct passwd *, Key *);
#ifdef KRB5
int auth_krb5(Authctxt *authctxt, krb5_data *auth, char **client, krb5_data *);
int auth_krb5_tgt(Authctxt *authctxt, krb5_data *tgt);
int auth_krb5_password(Authctxt *authctxt, const char *password);
void krb5_cleanup_proc(Authctxt *authctxt);
#endif /* KRB5 */
void do_authentication(Authctxt *);
void do_authentication2(Authctxt *);
void auth_log(Authctxt *, int, char *, char *);
void userauth_finish(Authctxt *, int, char *);
int auth_root_allowed(char *);
char *auth2_read_banner(void);
void privsep_challenge_enable(void);
int auth2_challenge(Authctxt *, char *);
void auth2_challenge_stop(Authctxt *);
int bsdauth_query(void *, char **, char **, u_int *, char ***, u_int **);
int bsdauth_respond(void *, u_int, char **);
int skey_query(void *, char **, char **, u_int *, char ***, u_int **);
int skey_respond(void *, u_int, char **);
int allowed_user(struct passwd *);
struct passwd * getpwnamallow(const char *user);
char *get_challenge(Authctxt *);
int verify_response(Authctxt *, const char *);
char *expand_filename(const char *, struct passwd *);
char *authorized_keys_file(struct passwd *);
char *authorized_keys_file2(struct passwd *);
int
secure_filename(FILE *, const char *, struct passwd *, char *, size_t);
HostStatus
check_key_in_hostfiles(struct passwd *, Key *, const char *,
const char *, const char *);
/* hostkey handling */
Key *get_hostkey_by_index(int);
Key *get_hostkey_by_type(int);
int get_hostkey_index(Key *);
int ssh1_session_key(BIGNUM *);
/* debug messages during authentication */
void auth_debug_add(const char *fmt,...) __attribute__((format(printf, 1, 2)));
void auth_debug_send(void);
void auth_debug_reset(void);
struct passwd *fakepw(void);
#define AUTH_FAIL_MAX 6
#define AUTH_FAIL_LOG (AUTH_FAIL_MAX/2)
#define AUTH_FAIL_MSG "Too many authentication failures for %.100s"
#define SKEY_PROMPT "\nS/Key Password: "
#endif
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