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
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
|
/*
SSSD
Kerberos 5 Backend Module -- tgt_req child
Authors:
Sumit Bose <sbose@redhat.com>
Copyright (C) 2009 Red Hat
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <krb5/krb5.h>
#include <sys/types.h>
#include <security/pam_modules.h>
#include "util/util.h"
#include "providers/dp_backend.h"
#include "providers/krb5/krb5_auth.h"
static int pack_response_packet(uint8_t *buf, int status, int type,
const char *data)
{
int len;
int p=0;
if ((3*sizeof(int32_t) + strlen(data)+1) > MAX_CHILD_MSG_SIZE) {
return -1;
}
((int32_t *)(&buf[p]))[0] = status;
p += sizeof(int32_t);
((int32_t *)(&buf[p]))[0] = type;
p += sizeof(int32_t);
len = strlen(data)+1;
((int32_t *)(&buf[p]))[0] = len;
p += sizeof(int32_t);
memcpy(&buf[p], data, len);
p += len;
return p;
}
void tgt_req_child(int fd, struct krb5_req *kr)
{
int ret;
krb5_error_code kerr = 0;
char *pass_str = NULL;
uint8_t buf[MAX_CHILD_MSG_SIZE];
int size = 0;
const char *cc_name;
char *env;
const char *krb5_error_msg;
ret = setgid(kr->pd->gr_gid);
if (ret == -1) {
DEBUG(1, ("setgid failed [%d][%s].\n", errno, strerror(errno)));
_exit(-1);
}
ret = setuid(kr->pd->pw_uid);
if (ret == -1) {
DEBUG(1, ("setuid failed [%d][%s].\n", errno, strerror(errno)));
_exit(-1);
}
ret = setegid(kr->pd->gr_gid);
if (ret == -1) {
DEBUG(1, ("setegid failed [%d][%s].\n", errno, strerror(errno)));
_exit(-1);
}
ret = seteuid(kr->pd->pw_uid);
if (ret == -1) {
DEBUG(1, ("seteuid failed [%d][%s].\n", errno, strerror(errno)));
_exit(-1);
}
pass_str = talloc_strndup(kr, (const char *) kr->pd->authtok,
kr->pd->authtok_size);
if (pass_str == NULL) {
DEBUG(1, ("talloc_strndup failed.\n"));
_exit(-1);
}
kerr = krb5_get_init_creds_password(kr->ctx, kr->creds, kr->princ,
pass_str, NULL, NULL, 0, NULL,
kr->options);
if (kerr != 0) {
KRB5_DEBUG(1, kerr);
goto childfailed;
}
memset(pass_str, 0, kr->pd->authtok_size);
talloc_free(pass_str);
memset(kr->pd->authtok, 0, kr->pd->authtok_size);
kerr = krb5_cc_default(kr->ctx, &kr->cc);
if (kerr != 0) {
KRB5_DEBUG(1, kerr);
goto childfailed;
}
kerr = krb5_cc_initialize(kr->ctx, kr->cc, kr->princ);
if (kerr != 0) {
KRB5_DEBUG(1, kerr);
goto childfailed;
}
kerr = krb5_cc_store_cred(kr->ctx, kr->cc, kr->creds);
if (kerr != 0) {
KRB5_DEBUG(1, kerr);
krb5_cc_destroy(kr->ctx, kr->cc);
goto childfailed;
}
cc_name = krb5_cc_get_name(kr->ctx, kr->cc);
if (cc_name == NULL) {
DEBUG(1, ("krb5_cc_get_name failed.\n"));
krb5_cc_destroy(kr->ctx, kr->cc);
_exit(-1);
}
env = talloc_asprintf(kr, "%s=%s",CCACHE_ENV_NAME, cc_name);
if (env == NULL) {
DEBUG(1, ("talloc_asprintf failed.\n"));
krb5_cc_destroy(kr->ctx, kr->cc);
_exit(-1);
}
size = pack_response_packet(buf, PAM_SUCCESS, PAM_ENV_ITEM, env);
if (size < 0) {
DEBUG(1, ("failed to create response message.\n"));
krb5_cc_destroy(kr->ctx, kr->cc);
_exit(-1);
}
kerr = 0;
childfailed:
if (kerr != 0 ) {
krb5_error_msg = krb5_get_error_message(krb5_error_ctx, kerr);
size = pack_response_packet(buf, PAM_SYSTEM_ERR, PAM_USER_INFO,
krb5_error_msg);
if (size < 0) {
DEBUG(1, ("failed to create response message.\n"));
krb5_cc_destroy(kr->ctx, kr->cc);
_exit(-1);
}
krb5_free_error_message(krb5_error_ctx, krb5_error_msg);
}
ret = write(fd, buf, size);
if (ret == -1) {
DEBUG(1, ("write failed [%d][%s].\n", errno, strerror(errno)));
krb5_cc_destroy(kr->ctx, kr->cc);
_exit(ret);
}
krb5_cc_close(kr->ctx, kr->cc);
_exit(0);
}
|
