authz-pam: Check that 'service' property is set
[qemu.git] / authz / pamacct.c
1 /*
2 * QEMU PAM authorization driver
3 *
4 * Copyright (c) 2018 Red Hat, Inc.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 *
19 */
20
21 #include "qemu/osdep.h"
22 #include "authz/pamacct.h"
23 #include "trace.h"
24 #include "qemu/module.h"
25 #include "qom/object_interfaces.h"
26
27 #include <security/pam_appl.h>
28
29
30 static bool qauthz_pam_is_allowed(QAuthZ *authz,
31 const char *identity,
32 Error **errp)
33 {
34 QAuthZPAM *pauthz = QAUTHZ_PAM(authz);
35 const struct pam_conv pam_conversation = { 0 };
36 pam_handle_t *pamh = NULL;
37 int ret;
38
39 trace_qauthz_pam_check(authz, identity, pauthz->service);
40 ret = pam_start(pauthz->service,
41 identity,
42 &pam_conversation,
43 &pamh);
44 if (ret != PAM_SUCCESS) {
45 error_setg(errp, "Unable to start PAM transaction: %s",
46 pam_strerror(NULL, ret));
47 return false;
48 }
49
50 ret = pam_acct_mgmt(pamh, PAM_SILENT);
51 pam_end(pamh, ret);
52 if (ret != PAM_SUCCESS) {
53 error_setg(errp, "Unable to authorize user '%s': %s",
54 identity, pam_strerror(pamh, ret));
55 return false;
56 }
57
58 return true;
59 }
60
61
62 static void
63 qauthz_pam_prop_set_service(Object *obj,
64 const char *service,
65 Error **errp G_GNUC_UNUSED)
66 {
67 QAuthZPAM *pauthz = QAUTHZ_PAM(obj);
68
69 g_free(pauthz->service);
70 pauthz->service = g_strdup(service);
71 }
72
73
74 static char *
75 qauthz_pam_prop_get_service(Object *obj,
76 Error **errp G_GNUC_UNUSED)
77 {
78 QAuthZPAM *pauthz = QAUTHZ_PAM(obj);
79
80 return g_strdup(pauthz->service);
81 }
82
83
84 static void
85 qauthz_pam_complete(UserCreatable *uc, Error **errp)
86 {
87 QAuthZPAM *pauthz = QAUTHZ_PAM(uc);
88
89 if (!pauthz->service) {
90 error_setg(errp, "The 'service' property must be set");
91 return;
92 }
93 }
94
95
96 static void
97 qauthz_pam_finalize(Object *obj)
98 {
99 QAuthZPAM *pauthz = QAUTHZ_PAM(obj);
100
101 g_free(pauthz->service);
102 }
103
104
105 static void
106 qauthz_pam_class_init(ObjectClass *oc, void *data)
107 {
108 UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
109 QAuthZClass *authz = QAUTHZ_CLASS(oc);
110
111 ucc->complete = qauthz_pam_complete;
112 authz->is_allowed = qauthz_pam_is_allowed;
113
114 object_class_property_add_str(oc, "service",
115 qauthz_pam_prop_get_service,
116 qauthz_pam_prop_set_service);
117 }
118
119
120 QAuthZPAM *qauthz_pam_new(const char *id,
121 const char *service,
122 Error **errp)
123 {
124 return QAUTHZ_PAM(
125 object_new_with_props(TYPE_QAUTHZ_PAM,
126 object_get_objects_root(),
127 id, errp,
128 "service", service,
129 NULL));
130 }
131
132
133 static const TypeInfo qauthz_pam_info = {
134 .parent = TYPE_QAUTHZ,
135 .name = TYPE_QAUTHZ_PAM,
136 .instance_size = sizeof(QAuthZPAM),
137 .instance_finalize = qauthz_pam_finalize,
138 .class_init = qauthz_pam_class_init,
139 .interfaces = (InterfaceInfo[]) {
140 { TYPE_USER_CREATABLE },
141 { }
142 }
143 };
144
145
146 static void
147 qauthz_pam_register_types(void)
148 {
149 type_register_static(&qauthz_pam_info);
150 }
151
152
153 type_init(qauthz_pam_register_types);