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
|
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
* Created: Sat Mar 18 05:11:38 1995 ylo
* Password authentication. This file contains the functions to check whether
* the password is valid for the user.
*/
#include "includes.h"
#ifndef HAVE_PAM
RCSID("$Id: auth-passwd.c,v 1.9 1999/12/16 04:10:45 damien Exp $");
#include "packet.h"
#include "ssh.h"
#include "servconf.h"
#include "xmalloc.h"
#ifdef HAVE_SHADOW_H
#include <shadow.h>
#endif
#ifdef HAVE_MD5_PASSWORDS
#include "md5crypt.h"
#endif
/*
* Tries to authenticate the user using password. Returns true if
* authentication succeeds.
*/
int
auth_password(struct passwd * pw, const char *password)
{
extern ServerOptions options;
char *encrypted_password;
#ifdef HAVE_SHADOW_H
struct spwd *spw;
#endif
if (pw->pw_uid == 0 && options.permit_root_login == 2)
return 0;
if (*password == '\0' && options.permit_empty_passwd == 0)
return 0;
/* deny if no user. */
if (pw == NULL)
return 0;
#ifdef SKEY
if (options.skey_authentication == 1) {
int ret = auth_skey_password(pw, password);
if (ret == 1 || ret == 0)
return ret;
/* Fall back to ordinary passwd authentication. */
}
#endif
#ifdef KRB4
if (options.kerberos_authentication == 1) {
int ret = auth_krb4_password(pw, password);
if (ret == 1 || ret == 0)
return ret;
/* Fall back to ordinary passwd authentication. */
}
#endif
/* Check for users with no password. */
if (strcmp(password, "") == 0 && strcmp(pw->pw_passwd, "") == 0)
return 1;
#ifdef HAVE_SHADOW_H
spw = getspnam(pw->pw_name);
if (spw == NULL)
return(0);
if ((spw->sp_namp == NULL) || (strcmp(pw->pw_name, spw->sp_namp) != 0))
fatal("Shadow lookup returned garbage.");
/* Check for users with no password. */
if (strcmp(password, "") == 0 && strcmp(spw->sp_pwdp, "") == 0)
return 1;
if (strlen(spw->sp_pwdp) < 3)
return(0);
/* Encrypt the candidate password using the proper salt. */
#ifdef HAVE_MD5_PASSWORDS
if (is_md5_salt(spw->sp_pwdp))
encrypted_password = md5_crypt(password, spw->sp_pwdp);
else
encrypted_password = crypt(password, spw->sp_pwdp);
#else /* HAVE_MD5_PASSWORDS */
encrypted_password = crypt(password, spw->sp_pwdp);
#endif /* HAVE_MD5_PASSWORDS */
/* Authentication is accepted if the encrypted passwords are identical. */
return (strcmp(encrypted_password, spw->sp_pwdp) == 0);
#else /* !HAVE_SHADOW_H */
encrypted_password = crypt(password,
(pw->pw_passwd[0] && pw->pw_passwd[1]) ? pw->pw_passwd : "xx");
/* Authentication is accepted if the encrypted passwords are identical. */
return (strcmp(encrypted_password, pw->pw_passwd) == 0);
#endif /* !HAVE_SHADOW_H */
}
#endif /* !HAVE_PAM */
|
