xref: /freebsd/crypto/openssh/auth.h (revision 52ec752989b2e6d4e9a59a8ff25d8ff596d85e62)
1 /*	$OpenBSD: auth.h,v 1.46 2003/08/28 12:54:34 markus Exp $	*/
2 /*	$FreeBSD$	*/
3 
4 /*
5  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  *
27  */
28 
29 #ifndef AUTH_H
30 #define AUTH_H
31 
32 #include "key.h"
33 #include "hostfile.h"
34 #include <openssl/rsa.h>
35 
36 #ifdef HAVE_LOGIN_CAP
37 #include <login_cap.h>
38 #endif
39 #ifdef BSD_AUTH
40 #include <bsd_auth.h>
41 #endif
42 #ifdef KRB5
43 #include <krb5.h>
44 #endif
45 
46 typedef struct Authctxt Authctxt;
47 typedef struct Authmethod Authmethod;
48 typedef struct KbdintDevice KbdintDevice;
49 
50 struct Authctxt {
51 	int		 success;
52 	int		 postponed;	/* authentication needs another step */
53 	int		 valid;		/* user exists and is allowed to login */
54 	int		 attempt;
55 	int		 failures;
56 	char		*user;		/* username sent by the client */
57 	char		*service;
58 	struct passwd	*pw;		/* set if 'valid' */
59 	char		*style;
60 	void		*kbdintctxt;
61 #ifdef BSD_AUTH
62 	auth_session_t	*as;
63 #endif
64 #ifdef KRB5
65 	krb5_context	 krb5_ctx;
66 	krb5_ccache	 krb5_fwd_ccache;
67 	krb5_principal	 krb5_user;
68 	char		*krb5_ticket_file;
69 #endif
70 	void		*methoddata;
71 };
72 /*
73  * Every authentication method has to handle authentication requests for
74  * non-existing users, or for users that are not allowed to login. In this
75  * case 'valid' is set to 0, but 'user' points to the username requested by
76  * the client.
77  */
78 
79 struct Authmethod {
80 	char	*name;
81 	int	(*userauth)(Authctxt *authctxt);
82 	int	*enabled;
83 };
84 
85 /*
86  * Keyboard interactive device:
87  * init_ctx	returns: non NULL upon success
88  * query	returns: 0 - success, otherwise failure
89  * respond	returns: 0 - success, 1 - need further interaction,
90  *		otherwise - failure
91  */
92 struct KbdintDevice
93 {
94 	const char *name;
95 	void*	(*init_ctx)(Authctxt*);
96 	int	(*query)(void *ctx, char **name, char **infotxt,
97 		    u_int *numprompts, char ***prompts, u_int **echo_on);
98 	int	(*respond)(void *ctx, u_int numresp, char **responses);
99 	void	(*free_ctx)(void *ctx);
100 };
101 
102 int      auth_rhosts(struct passwd *, const char *);
103 int
104 auth_rhosts2(struct passwd *, const char *, const char *, const char *);
105 
106 int	 auth_rhosts_rsa(struct passwd *, char *, Key *);
107 int      auth_password(Authctxt *, const char *);
108 int      auth_rsa(struct passwd *, BIGNUM *);
109 int      auth_rsa_challenge_dialog(Key *);
110 BIGNUM	*auth_rsa_generate_challenge(Key *);
111 int	 auth_rsa_verify_response(Key *, BIGNUM *, u_char[]);
112 int	 auth_rsa_key_allowed(struct passwd *, BIGNUM *, Key **);
113 
114 int	 auth_rhosts_rsa_key_allowed(struct passwd *, char *, char *, Key *);
115 int	 hostbased_key_allowed(struct passwd *, const char *, char *, Key *);
116 int	 user_key_allowed(struct passwd *, Key *);
117 
118 #ifdef KRB5
119 int	auth_krb5(Authctxt *authctxt, krb5_data *auth, char **client, krb5_data *);
120 int	auth_krb5_tgt(Authctxt *authctxt, krb5_data *tgt);
121 int	auth_krb5_password(Authctxt *authctxt, const char *password);
122 void	krb5_cleanup_proc(void *authctxt);
123 #endif /* KRB5 */
124 
125 #include "auth-pam.h"
126 
127 Authctxt *do_authentication(void);
128 Authctxt *do_authentication2(void);
129 
130 Authctxt *authctxt_new(void);
131 void	auth_log(Authctxt *, int, char *, char *);
132 void	userauth_finish(Authctxt *, int, char *);
133 int	auth_root_allowed(char *);
134 
135 char	*auth2_read_banner(void);
136 
137 void	privsep_challenge_enable(void);
138 
139 int	auth2_challenge(Authctxt *, char *);
140 void	auth2_challenge_stop(Authctxt *);
141 int	bsdauth_query(void *, char **, char **, u_int *, char ***, u_int **);
142 int	bsdauth_respond(void *, u_int, char **);
143 int	skey_query(void *, char **, char **, u_int *, char ***, u_int **);
144 int	skey_respond(void *, u_int, char **);
145 
146 int	allowed_user(struct passwd *);
147 struct passwd * getpwnamallow(const char *user);
148 
149 char	*get_challenge(Authctxt *);
150 int	verify_response(Authctxt *, const char *);
151 void	abandon_challenge_response(Authctxt *);
152 
153 struct passwd * auth_get_user(void);
154 
155 char	*expand_filename(const char *, struct passwd *);
156 char	*authorized_keys_file(struct passwd *);
157 char	*authorized_keys_file2(struct passwd *);
158 
159 int
160 secure_filename(FILE *, const char *, struct passwd *, char *, size_t);
161 
162 HostStatus
163 check_key_in_hostfiles(struct passwd *, Key *, const char *,
164     const char *, const char *);
165 
166 /* hostkey handling */
167 Key	*get_hostkey_by_index(int);
168 Key	*get_hostkey_by_type(int);
169 int	 get_hostkey_index(Key *);
170 int	 ssh1_session_key(BIGNUM *);
171 
172 /* debug messages during authentication */
173 void	 auth_debug_add(const char *fmt,...) __attribute__((format(printf, 1, 2)));
174 void	 auth_debug_send(void);
175 void	 auth_debug_reset(void);
176 
177 struct passwd *fakepw(void);
178 
179 #define AUTH_FAIL_MAX 6
180 #define AUTH_FAIL_LOG (AUTH_FAIL_MAX/2)
181 #define AUTH_FAIL_MSG "Too many authentication failures for %.100s"
182 
183 #ifdef SKEY
184 #ifdef OPIE
185 #define SKEY_PROMPT "\nOPIE Password: "
186 #else
187 #define SKEY_PROMPT "\nS/Key Password: "
188 #endif
189 #endif
190 
191 #endif
192