Annotation of src/usr.bin/ssh/auth-passwd.c, Revision 1.41
1.41 ! djm 1: /* $OpenBSD: auth-passwd.c,v 1.40 2006/08/03 03:34:41 deraadt 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:
1.37 stevesk 39: #include <sys/types.h>
40:
41: #include <pwd.h>
1.39 stevesk 42: #include <stdio.h>
1.38 stevesk 43: #include <string.h>
1.40 deraadt 44: #include <stdarg.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"
1.40 deraadt 50: #include "key.h"
51: #include "hostfile.h"
1.19 markus 52: #include "auth.h"
1.31 markus 53: #include "auth-options.h"
1.19 markus 54:
1.32 otto 55: extern Buffer loginmsg;
1.31 markus 56: extern ServerOptions options;
57: int sys_auth_passwd(Authctxt *, const char *);
1.22 markus 58:
1.32 otto 59: extern login_cap_t *lc;
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);
109: if (authctxt->valid) {
110: pwwarntime = login_getcaptime(lc, "password-warn", TWO_WEEKS,
111: TWO_WEEKS);
112: acwarntime = login_getcaptime(lc, "expire-warn", TWO_WEEKS,
113: TWO_WEEKS);
114: }
115: if (pwtimeleft != 0 && pwtimeleft < pwwarntime) {
116: daysleft = pwtimeleft / DAY + 1;
117: snprintf(buf, sizeof(buf),
118: "Your password will expire in %lld day%s.\n",
119: daysleft, daysleft == 1 ? "" : "s");
120: buffer_append(&loginmsg, buf, strlen(buf));
121: }
122: if (actimeleft != 0 && actimeleft < acwarntime) {
123: daysleft = actimeleft / DAY + 1;
124: snprintf(buf, sizeof(buf),
125: "Your account will expire in %lld day%s.\n",
126: daysleft, daysleft == 1 ? "" : "s");
127: buffer_append(&loginmsg, buf, strlen(buf));
128: }
129: }
130:
1.31 markus 131: int
132: sys_auth_passwd(Authctxt *authctxt, const char *password)
133: {
134: struct passwd *pw = authctxt->pw;
135: auth_session_t *as;
1.32 otto 136: static int expire_checked = 0;
1.31 markus 137:
138: as = auth_usercheck(pw->pw_name, authctxt->style, "auth-ssh",
139: (char *)password);
1.34 otto 140: if (as == NULL)
141: return (0);
1.31 markus 142: if (auth_getstate(as) & AUTH_PWEXPIRED) {
143: auth_close(as);
144: disable_forwarding();
145: authctxt->force_pwchange = 1;
146: return (1);
147: } else {
1.32 otto 148: if (!expire_checked) {
149: expire_checked = 1;
150: warn_expiry(authctxt, as);
151: }
1.31 markus 152: return (auth_close(as));
153: }
154: }
1.27 stevesk 155: #else
1.31 markus 156: int
157: sys_auth_passwd(Authctxt *authctxt, const char *password)
158: {
159: struct passwd *pw = authctxt->pw;
160: char *encrypted_password;
161:
1.10 markus 162: /* Check for users with no password. */
1.12 markus 163: if (strcmp(password, "") == 0 && strcmp(pw->pw_passwd, "") == 0)
1.31 markus 164: return (1);
165:
166: /* Encrypt the candidate password using the proper salt. */
167: encrypted_password = crypt(password,
168: (pw->pw_passwd[0] && pw->pw_passwd[1]) ?
169: pw->pw_passwd : "xx");
170:
171: /*
172: * Authentication is accepted if the encrypted passwords
173: * are identical.
174: */
175: return (strcmp(encrypted_password, pw->pw_passwd) == 0);
176: }
1.27 stevesk 177: #endif