1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
/* $OpenBSD: auth.h,v 1.53 2006/04/20 09:27:09 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 <signal.h>
#include "key.h"
#include "hostfile.h"
#include "buffer.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 {
sig_atomic_t success;
int postponed; /* authentication needs another step */
int valid; /* user exists and is allowed to login */
int attempt;
int failures;
int force_pwchange;
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;
char *krb5_ccname;
#endif
Buffer *loginmsg;
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 */
#if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE)
#include <shadow.h>
int auth_shadow_acctexpired(struct spwd *);
int auth_shadow_pwexpired(Authctxt *);
#endif
#include "auth-pam.h"
#include "audit.h"
void remove_kbdint_device(const char *);
void disable_forwarding(void);
void do_authentication(Authctxt *);
void do_authentication2(Authctxt *);
void auth_log(Authctxt *, int, char *, char *);
void userauth_finish(Authctxt *, int, char *);
void userauth_send_banner(const 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 *);
void abandon_challenge_response(Authctxt *);
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);
int sys_auth_passwd(Authctxt *, const char *);
#define AUTH_FAIL_MSG "Too many authentication failures for %.100s"
#define SKEY_PROMPT "\nS/Key Password: "
#if defined(KRB5) && !defined(HEIMDAL)
#include <krb5.h>
krb5_error_code ssh_krb5_cc_gen(krb5_context, krb5_ccache *);
#endif
#endif
|