s4:kdc Streamline client access verification call
[ira/wip.git] / source4 / kdc / wdc-samba4.c
1 /*
2    Unix SMB/CIFS implementation.
3
4    PAC Glue between Samba and the KDC
5
6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005-2009
7    Copyright (C) Simo Sorce <idra@samba.org> 2010
8
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 3 of the License, or
12    (at your option) any later version.
13
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License for more details.
18
19
20    You should have received a copy of the GNU General Public License
21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
22 */
23
24 #include "includes.h"
25 #include "../libds/common/flags.h"
26 #include "auth/auth.h"
27 #include "kdc/kdc.h"
28 #include "param/param.h"
29 #include "kdc/pac-glue.h"
30
31 /* Given the right private pointer from hdb_samba4, get a PAC from the attached ldb messages */
32 static krb5_error_code samba_wdc_get_pac(void *priv, krb5_context context,
33                                          struct hdb_entry_ex *client,
34                                          krb5_pac *pac)
35 {
36         TALLOC_CTX *mem_ctx;
37         DATA_BLOB *pac_blob;
38         krb5_error_code ret;
39         NTSTATUS nt_status;
40
41         mem_ctx = talloc_named(client->ctx, 0, "samba_get_pac context");
42         if (!mem_ctx) {
43                 return ENOMEM;
44         }
45
46         nt_status = samba_kdc_get_pac_blob(mem_ctx, client, &pac_blob);
47         if (!NT_STATUS_IS_OK(nt_status)) {
48                 talloc_free(mem_ctx);
49                 return EINVAL;
50         }
51
52         ret = samba_make_krb5_pac(context, pac_blob, pac);
53
54         talloc_free(mem_ctx);
55         return ret;
56 }
57
58 /* Resign (and reform, including possibly new groups) a PAC */
59
60 static krb5_error_code samba_wdc_reget_pac(void *priv, krb5_context context,
61                                            const krb5_principal client_principal,
62                                            struct hdb_entry_ex *client,
63                                            struct hdb_entry_ex *server, krb5_pac *pac)
64 {
65         struct samba_kdc_entry *p = talloc_get_type(server->ctx, struct samba_kdc_entry);
66         TALLOC_CTX *mem_ctx = talloc_named(p, 0, "samba_kdc_reget_pac context");
67         DATA_BLOB *pac_blob;
68         krb5_error_code ret;
69         NTSTATUS nt_status;
70
71         if (!mem_ctx) {
72                 return ENOMEM;
73         }
74
75         pac_blob = talloc_zero(mem_ctx, DATA_BLOB);
76         if (!pac_blob) {
77                 talloc_free(mem_ctx);
78                 return ENOMEM;
79         }
80
81         /* The user account may be set not to want the PAC */
82         if (!samba_princ_needs_pac(server)) {
83                 talloc_free(mem_ctx);
84                 return EINVAL;
85         }
86
87         nt_status = samba_kdc_update_pac_blob(mem_ctx, context,
88                                               p->kdc_db_ctx->ic_ctx,
89                                               pac, pac_blob);
90         if (!NT_STATUS_IS_OK(nt_status)) {
91                 DEBUG(0, ("Building PAC failed: %s\n",
92                           nt_errstr(nt_status)));
93                 talloc_free(mem_ctx);
94                 return EINVAL;
95         }
96
97         /* We now completly regenerate this pac */
98         krb5_pac_free(context, *pac);
99
100         ret = samba_make_krb5_pac(context, pac_blob, pac);
101
102         talloc_free(mem_ctx);
103         return ret;
104 }
105
106 static char *get_netbios_name(TALLOC_CTX *mem_ctx, HostAddresses *addrs)
107 {
108         char *nb_name = NULL;
109         int len, i;
110
111         for (i = 0; addrs && i < addrs->len; i++) {
112                 if (addrs->val[i].addr_type != KRB5_ADDRESS_NETBIOS) {
113                         continue;
114                 }
115                 len = MIN(addrs->val[i].address.length, 15);
116                 nb_name = talloc_strndup(mem_ctx,
117                                          addrs->val[i].address.data, len);
118                 if (nb_name) {
119                         break;
120                 }
121         }
122
123         if (nb_name == NULL) {
124                 return NULL;
125         }
126
127         /* Strip space padding */
128         i = strlen(nb_name) - 1;
129         while (i > 0 && nb_name[i] == ' ') {
130                 nb_name[i] = '\0';
131         }
132
133         return nb_name;
134 }
135
136 static krb5_data fill_krb5_data(void *data, size_t length)
137 {
138         krb5_data kdata;
139
140         kdata.data = data;
141         kdata.length = length;
142
143         return kdata;
144 }
145
146 static krb5_error_code samba_wdc_check_client_access(void *priv,
147                                                      krb5_context context,
148                                                      krb5_kdc_configuration *config,
149                                                      hdb_entry_ex *client_ex, const char *client_name,
150                                                      hdb_entry_ex *server_ex, const char *server_name,
151                                                      KDC_REQ *req,
152                                                      krb5_data *e_data)
153 {
154         struct samba_kdc_entry *kdc_entry;
155         bool password_change;
156         char *workstation;
157         NTSTATUS nt_status;
158
159         kdc_entry = talloc_get_type(client_ex->ctx, struct samba_kdc_entry);
160         password_change = (server_ex && server_ex->entry.flags.change_pw);
161         workstation = get_netbios_name((TALLOC_CTX *)client_ex->ctx,
162                                         req->req_body.addresses);
163
164         nt_status = samba_kdc_check_client_access(kdc_entry,
165                                                   client_name,
166                                                   workstation,
167                                                   password_change);
168
169         if (!NT_STATUS_IS_OK(nt_status)) {
170                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_MEMORY)) {
171                         return ENOMEM;
172                 }
173
174                 if (e_data) {
175                         DATA_BLOB data;
176
177                         samba_kdc_build_edata_reply(nt_status, &data);
178                         *e_data = fill_krb5_data(data.data, data.length);
179                 }
180
181                 return samba_kdc_map_policy_err(nt_status);
182         }
183
184         /* Now do the standard Heimdal check */
185         return kdc_check_flags(context, config,
186                                client_ex, client_name,
187                                server_ex, server_name,
188                                req->msg_type == krb_as_req);
189 }
190
191 static krb5_error_code samba_wdc_plugin_init(krb5_context context, void **ptr)
192 {
193         *ptr = NULL;
194         return 0;
195 }
196
197 static void samba_wdc_plugin_fini(void *ptr)
198 {
199         return;
200 }
201
202 struct krb5plugin_windc_ftable windc_plugin_table = {
203         .minor_version = KRB5_WINDC_PLUGING_MINOR,
204         .init = samba_wdc_plugin_init,
205         .fini = samba_wdc_plugin_fini,
206         .pac_generate = samba_wdc_get_pac,
207         .pac_verify = samba_wdc_reget_pac,
208         .client_access = samba_wdc_check_client_access,
209 };
210
211