Annotation of src/usr.bin/ssh/auth-passwd.c, Revision 1.38
1.38 ! stevesk 1: /* $OpenBSD: auth-passwd.c,v 1.37 2006/07/06 16:03:53 stevesk Exp $ */
1.1 deraadt 2: /*
1.11 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * Password authentication. This file contains the functions to check whether
7: * the password is valid for the user.
1.17 deraadt 8: *
9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
14: *
15: * Copyright (c) 1999 Dug Song. All rights reserved.
16: * Copyright (c) 2000 Markus Friedl. All rights reserved.
17: *
18: * Redistribution and use in source and binary forms, with or without
19: * modification, are permitted provided that the following conditions
20: * are met:
21: * 1. Redistributions of source code must retain the above copyright
22: * notice, this list of conditions and the following disclaimer.
23: * 2. Redistributions in binary form must reproduce the above copyright
24: * notice, this list of conditions and the following disclaimer in the
25: * documentation and/or other materials provided with the distribution.
26: *
27: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
28: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
29: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
30: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
31: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
32: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
36: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.11 deraadt 37: */
1.1 deraadt 38:
39: #include "includes.h"
1.37 stevesk 40:
41: #include <sys/types.h>
42:
43: #include <pwd.h>
1.38 ! stevesk 44: #include <string.h>
1.1 deraadt 45:
46: #include "packet.h"
1.32 otto 47: #include "buffer.h"
1.20 markus 48: #include "log.h"
1.1 deraadt 49: #include "servconf.h"
1.19 markus 50: #include "auth.h"
1.31 markus 51: #include "auth-options.h"
1.19 markus 52:
1.32 otto 53: extern Buffer loginmsg;
1.31 markus 54: extern ServerOptions options;
55: int sys_auth_passwd(Authctxt *, const char *);
1.22 markus 56:
1.32 otto 57: #ifdef HAVE_LOGIN_CAP
58: extern login_cap_t *lc;
59: #endif
60:
61:
62: #define DAY (24L * 60 * 60) /* 1 day in seconds */
63: #define TWO_WEEKS (2L * 7 * DAY) /* 2 weeks in seconds */
64:
1.31 markus 65: static void
66: disable_forwarding(void)
67: {
68: no_port_forwarding_flag = 1;
69: no_agent_forwarding_flag = 1;
70: no_x11_forwarding_flag = 1;
71: }
1.22 markus 72:
1.11 deraadt 73: /*
74: * Tries to authenticate the user using password. Returns true if
75: * authentication succeeds.
76: */
1.15 markus 77: int
1.22 markus 78: auth_password(Authctxt *authctxt, const char *password)
1.1 deraadt 79: {
1.22 markus 80: struct passwd * pw = authctxt->pw;
1.29 markus 81: int ok = authctxt->valid;
1.7 markus 82:
1.21 markus 83: if (pw->pw_uid == 0 && options.permit_root_login != PERMIT_YES)
1.29 markus 84: ok = 0;
1.26 mouring 85: if (*password == '\0' && options.permit_empty_passwd == 0)
1.10 markus 86: return 0;
1.23 dugsong 87: #ifdef KRB5
88: if (options.kerberos_authentication == 1) {
89: int ret = auth_krb5_password(authctxt, password);
1.13 markus 90: if (ret == 1 || ret == 0)
1.29 markus 91: return ret && ok;
1.10 markus 92: /* Fall back to ordinary passwd authentication. */
1.2 dugsong 93: }
1.13 markus 94: #endif
1.31 markus 95: return (sys_auth_passwd(authctxt, password) && ok);
96: }
97:
1.23 dugsong 98: #ifdef BSD_AUTH
1.32 otto 99: static void
100: warn_expiry(Authctxt *authctxt, auth_session_t *as)
101: {
102: char buf[256];
103: quad_t pwtimeleft, actimeleft, daysleft, pwwarntime, acwarntime;
104:
105: pwwarntime = acwarntime = TWO_WEEKS;
106:
107: pwtimeleft = auth_check_change(as);
108: actimeleft = auth_check_expire(as);
1.33 dtucker 109: #ifdef HAVE_LOGIN_CAP
1.32 otto 110: if (authctxt->valid) {
111: pwwarntime = login_getcaptime(lc, "password-warn", TWO_WEEKS,
112: TWO_WEEKS);
113: acwarntime = login_getcaptime(lc, "expire-warn", TWO_WEEKS,
114: TWO_WEEKS);
115: }
116: #endif
117: if (pwtimeleft != 0 && pwtimeleft < pwwarntime) {
118: daysleft = pwtimeleft / DAY + 1;
119: snprintf(buf, sizeof(buf),
120: "Your password will expire in %lld day%s.\n",
121: daysleft, daysleft == 1 ? "" : "s");
122: buffer_append(&loginmsg, buf, strlen(buf));
123: }
124: if (actimeleft != 0 && actimeleft < acwarntime) {
125: daysleft = actimeleft / DAY + 1;
126: snprintf(buf, sizeof(buf),
127: "Your account will expire in %lld day%s.\n",
128: daysleft, daysleft == 1 ? "" : "s");
129: buffer_append(&loginmsg, buf, strlen(buf));
130: }
131: }
132:
1.31 markus 133: int
134: sys_auth_passwd(Authctxt *authctxt, const char *password)
135: {
136: struct passwd *pw = authctxt->pw;
137: auth_session_t *as;
1.32 otto 138: static int expire_checked = 0;
1.31 markus 139:
140: as = auth_usercheck(pw->pw_name, authctxt->style, "auth-ssh",
141: (char *)password);
1.34 otto 142: if (as == NULL)
143: return (0);
1.31 markus 144: if (auth_getstate(as) & AUTH_PWEXPIRED) {
145: auth_close(as);
146: disable_forwarding();
147: authctxt->force_pwchange = 1;
148: return (1);
149: } else {
1.32 otto 150: if (!expire_checked) {
151: expire_checked = 1;
152: warn_expiry(authctxt, as);
153: }
1.31 markus 154: return (auth_close(as));
155: }
156: }
1.27 stevesk 157: #else
1.31 markus 158: int
159: sys_auth_passwd(Authctxt *authctxt, const char *password)
160: {
161: struct passwd *pw = authctxt->pw;
162: char *encrypted_password;
163:
1.10 markus 164: /* Check for users with no password. */
1.12 markus 165: if (strcmp(password, "") == 0 && strcmp(pw->pw_passwd, "") == 0)
1.31 markus 166: return (1);
167:
168: /* Encrypt the candidate password using the proper salt. */
169: encrypted_password = crypt(password,
170: (pw->pw_passwd[0] && pw->pw_passwd[1]) ?
171: pw->pw_passwd : "xx");
172:
173: /*
174: * Authentication is accepted if the encrypted passwords
175: * are identical.
176: */
177: return (strcmp(encrypted_password, pw->pw_passwd) == 0);
178: }
1.27 stevesk 179: #endif