Mercurial > dropbear

annotate svr-authpasswd.c @ 1654:cc0fc5131c5c

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Rename EPKA -> Plugin
author Matt Johnston <matt@ucc.asn.au>
date Wed, 15 May 2019 21:59:45 +0800
parents 228b086794b7
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 /*
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 * Dropbear - a SSH2 server
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 *
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 * Copyright (c) 2002,2003 Matt Johnston
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 * All rights reserved.
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 *
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
7 * Permission is hereby granted, free of charge, to any person obtaining a copy
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 * of this software and associated documentation files (the "Software"), to deal
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 * in the Software without restriction, including without limitation the rights
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
11 * copies of the Software, and to permit persons to whom the Software is
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
12 * furnished to do so, subject to the following conditions:
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
13 *
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
14 * The above copyright notice and this permission notice shall be included in
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
15 * all copies or substantial portions of the Software.
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16 *
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
23 * SOFTWARE. */
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 /* Validates a user password */
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
27 #include "includes.h"
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
28 #include "session.h"
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
29 #include "buffer.h"
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
30 #include "dbutil.h"
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
31 #include "auth.h"
692
c58a15983808 Allow configuring "allow blank password option" at runtime
Paul Eggleton <paul.eggleton@linux.intel.com>
parents: 677
diff changeset
32 #include "runopts.h"
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
33
1295
750ec4ec4cbe Convert #ifdef to #if, other build changes
Matt Johnston <matt@ucc.asn.au>
parents: 1122
diff changeset
34 #if DROPBEAR_SVR_PASSWORD_AUTH
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
35
1086
50f8a24953e6 note about constant_time_strcmp and lengths
Matt Johnston <matt@ucc.asn.au>
parents: 817
diff changeset
36 /* not constant time when strings are differing lengths.
50f8a24953e6 note about constant_time_strcmp and lengths
Matt Johnston <matt@ucc.asn.au>
parents: 817
diff changeset
37 string content isn't leaked, and crypt hashes are predictable length. */
817
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
38 static int constant_time_strcmp(const char* a, const char* b) {
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
39 size_t la = strlen(a);
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
40 size_t lb = strlen(b);
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
41
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
42 if (la != lb) {
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
43 return 1;
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
44 }
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
45
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
46 return constant_time_memcmp(a, b, la);
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
47 }
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
48
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
49 /* Process a password auth request, sending success or failure messages as
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
50 * appropriate */
1616
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
51 void svr_auth_password(int valid_user) {
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
52
70
b0316ce64e4b Merging in the changes from 0.41-0.43 main Dropbear tree
Matt Johnston <matt@ucc.asn.au>
parents: 68
diff changeset
53 char * passwdcrypt = NULL; /* the crypt from /etc/passwd or /etc/shadow */
b0316ce64e4b Merging in the changes from 0.41-0.43 main Dropbear tree
Matt Johnston <matt@ucc.asn.au>
parents: 68
diff changeset
54 char * testcrypt = NULL; /* crypt generated from the user's password sent */
1616
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
55 char * password = NULL;
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
56 unsigned int passwordlen;
70
b0316ce64e4b Merging in the changes from 0.41-0.43 main Dropbear tree
Matt Johnston <matt@ucc.asn.au>
parents: 68
diff changeset
57 unsigned int changepw;
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
58
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
59 /* check if client wants to change password */
179
161557a9dde8 * fix longstanding bug with connections being closed on failure to
Matt Johnston <matt@ucc.asn.au>
parents: 158
diff changeset
60 changepw = buf_getbool(ses.payload);
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
61 if (changepw) {
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
62 /* not implemented by this server */
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
63 send_msg_userauth_failure(0, 1);
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
64 return;
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
65 }
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
66
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
67 password = buf_getstring(ses.payload, &passwordlen);
1640
228b086794b7 limit password length to 100
Matt Johnston <matt@ucc.asn.au>
parents: 1616
diff changeset
68 if (valid_user && passwordlen <= DROPBEAR_MAX_PASSWORD_LEN) {
1616
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
69 /* the first bytes of passwdcrypt are the salt */
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
70 passwdcrypt = ses.authstate.pw_passwd;
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
71 testcrypt = crypt(password, passwdcrypt);
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
72 }
54
a48ba599292a burn the buffer a bit earlier
Matt Johnston <matt@ucc.asn.au>
parents: 53
diff changeset
73 m_burn(password, passwordlen);
a48ba599292a burn the buffer a bit earlier
Matt Johnston <matt@ucc.asn.au>
parents: 53
diff changeset
74 m_free(password);
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
75
1616
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
76 /* After we have got the payload contents we can exit if the username
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
77 is invalid. Invalid users have already been logged. */
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
78 if (!valid_user) {
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
79 send_msg_userauth_failure(0, 1);
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
80 return;
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
81 }
5d2d1021ca00 Wait to fail invalid usernames
Matt Johnston <matt@ucc.asn.au>
parents: 1295
diff changeset
82
1640
228b086794b7 limit password length to 100
Matt Johnston <matt@ucc.asn.au>
parents: 1616
diff changeset
83 if (passwordlen > DROPBEAR_MAX_PASSWORD_LEN) {
228b086794b7 limit password length to 100
Matt Johnston <matt@ucc.asn.au>
parents: 1616
diff changeset
84 dropbear_log(LOG_WARNING,
228b086794b7 limit password length to 100
Matt Johnston <matt@ucc.asn.au>
parents: 1616
diff changeset
85 "Too-long password attempt for '%s' from %s",
228b086794b7 limit password length to 100
Matt Johnston <matt@ucc.asn.au>
parents: 1616
diff changeset
86 ses.authstate.pw_name,
228b086794b7 limit password length to 100
Matt Johnston <matt@ucc.asn.au>
parents: 1616
diff changeset
87 svr_ses.addrstring);
228b086794b7 limit password length to 100
Matt Johnston <matt@ucc.asn.au>
parents: 1616
diff changeset
88 send_msg_userauth_failure(0, 1);
228b086794b7 limit password length to 100
Matt Johnston <matt@ucc.asn.au>
parents: 1616
diff changeset
89 return;
228b086794b7 limit password length to 100
Matt Johnston <matt@ucc.asn.au>
parents: 1616
diff changeset
90 }
228b086794b7 limit password length to 100
Matt Johnston <matt@ucc.asn.au>
parents: 1616
diff changeset
91
790
7bd88d546627 Avoid segfault for locked accounts (invalid salt to crypt())
Matt Johnston <matt@ucc.asn.au>
parents: 692
diff changeset
92 if (testcrypt == NULL) {
7bd88d546627 Avoid segfault for locked accounts (invalid salt to crypt())
Matt Johnston <matt@ucc.asn.au>
parents: 692
diff changeset
93 /* crypt() with an invalid salt like "!!" */
7bd88d546627 Avoid segfault for locked accounts (invalid salt to crypt())
Matt Johnston <matt@ucc.asn.au>
parents: 692
diff changeset
94 dropbear_log(LOG_WARNING, "User account '%s' is locked",
7bd88d546627 Avoid segfault for locked accounts (invalid salt to crypt())
Matt Johnston <matt@ucc.asn.au>
parents: 692
diff changeset
95 ses.authstate.pw_name);
7bd88d546627 Avoid segfault for locked accounts (invalid salt to crypt())
Matt Johnston <matt@ucc.asn.au>
parents: 692
diff changeset
96 send_msg_userauth_failure(0, 1);
7bd88d546627 Avoid segfault for locked accounts (invalid salt to crypt())
Matt Johnston <matt@ucc.asn.au>
parents: 692
diff changeset
97 return;
7bd88d546627 Avoid segfault for locked accounts (invalid salt to crypt())
Matt Johnston <matt@ucc.asn.au>
parents: 692
diff changeset
98 }
7bd88d546627 Avoid segfault for locked accounts (invalid salt to crypt())
Matt Johnston <matt@ucc.asn.au>
parents: 692
diff changeset
99
628
d40f3cc47aed - Add ALLOW_BLANK_PASSWORD option
Matt Johnston <matt@ucc.asn.au>
parents: 594
diff changeset
100 /* check for empty password */
d40f3cc47aed - Add ALLOW_BLANK_PASSWORD option
Matt Johnston <matt@ucc.asn.au>
parents: 594
diff changeset
101 if (passwdcrypt[0] == '\0') {
d40f3cc47aed - Add ALLOW_BLANK_PASSWORD option
Matt Johnston <matt@ucc.asn.au>
parents: 594
diff changeset
102 dropbear_log(LOG_WARNING, "User '%s' has blank password, rejected",
d40f3cc47aed - Add ALLOW_BLANK_PASSWORD option
Matt Johnston <matt@ucc.asn.au>
parents: 594
diff changeset
103 ses.authstate.pw_name);
d40f3cc47aed - Add ALLOW_BLANK_PASSWORD option
Matt Johnston <matt@ucc.asn.au>
parents: 594
diff changeset
104 send_msg_userauth_failure(0, 1);
d40f3cc47aed - Add ALLOW_BLANK_PASSWORD option
Matt Johnston <matt@ucc.asn.au>
parents: 594
diff changeset
105 return;
d40f3cc47aed - Add ALLOW_BLANK_PASSWORD option
Matt Johnston <matt@ucc.asn.au>
parents: 594
diff changeset
106 }
d40f3cc47aed - Add ALLOW_BLANK_PASSWORD option
Matt Johnston <matt@ucc.asn.au>
parents: 594
diff changeset
107
817
a625f9e135a4 Constant time memcmp for the hmac and password crypt
Matt Johnston <matt@ucc.asn.au>
parents: 790
diff changeset
108 if (constant_time_strcmp(testcrypt, passwdcrypt) == 0) {
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
109 /* successful authentication */
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
110 dropbear_log(LOG_NOTICE,
594
a98a2138364a Improve capitalisation for all logged strings
Matt Johnston <matt@ucc.asn.au>
parents: 464
diff changeset
111 "Password auth succeeded for '%s' from %s",
464
4317be8b7cf9 Make a copy of passwd fields since getpwnam()'s retval isn't safe to keep
Matt Johnston <matt@ucc.asn.au>
parents: 179
diff changeset
112 ses.authstate.pw_name,
158
364a75cfebab Log the IP along with auth success/fail attempts
Matt Johnston <matt@ucc.asn.au>
parents: 119
diff changeset
113 svr_ses.addrstring);
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
114 send_msg_userauth_success();
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
115 } else {
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
116 dropbear_log(LOG_WARNING,
594
a98a2138364a Improve capitalisation for all logged strings
Matt Johnston <matt@ucc.asn.au>
parents: 464
diff changeset
117 "Bad password attempt for '%s' from %s",
464
4317be8b7cf9 Make a copy of passwd fields since getpwnam()'s retval isn't safe to keep
Matt Johnston <matt@ucc.asn.au>
parents: 179
diff changeset
118 ses.authstate.pw_name,
158
364a75cfebab Log the IP along with auth success/fail attempts
Matt Johnston <matt@ucc.asn.au>
parents: 119
diff changeset
119 svr_ses.addrstring);
4
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
120 send_msg_userauth_failure(0, 1);
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
121 }
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
122 }
fe6bca95afa7 Makefile.in contains updated files required
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
123
68
eee77ac31ccc cleaning up the pubkey defines
Matt Johnston <matt@ucc.asn.au>
parents: 54
diff changeset
124 #endif