xref: /qemu/backends/tpm/tpm_backend.c (revision 191adc9476371ad94771609d8b9a968d9332a962)
1 /*
2  * QEMU TPM Backend
3  *
4  * Copyright IBM, Corp. 2013
5  *
6  * Authors:
7  *  Stefan Berger   <stefanb@us.ibm.com>
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
10  * See the COPYING file in the top-level directory.
11  *
12  * Based on backends/rng.c by Anthony Liguori
13  */
14 
15 #include "qemu/osdep.h"
16 #include "sysemu/tpm_backend.h"
17 #include "qapi/error.h"
18 #include "qapi/qmp/qerror.h"
19 #include "sysemu/tpm.h"
20 #include "qemu/thread.h"
21 #include "qemu/main-loop.h"
22 
23 static void tpm_backend_request_completed_bh(void *opaque)
24 {
25     TPMBackend *s = TPM_BACKEND(opaque);
26     TPMIfClass *tic = TPM_IF_GET_CLASS(s->tpmif);
27 
28     tic->request_completed(s->tpmif);
29 }
30 
31 static void tpm_backend_worker_thread(gpointer data, gpointer user_data)
32 {
33     TPMBackend *s = TPM_BACKEND(user_data);
34     TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
35 
36     assert(k->handle_request != NULL);
37     k->handle_request(s, (TPMBackendCmd *)data);
38 
39     qemu_bh_schedule(s->bh);
40 }
41 
42 static void tpm_backend_thread_end(TPMBackend *s)
43 {
44     if (s->thread_pool) {
45         g_thread_pool_free(s->thread_pool, FALSE, TRUE);
46         s->thread_pool = NULL;
47     }
48 }
49 
50 enum TpmType tpm_backend_get_type(TPMBackend *s)
51 {
52     TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
53 
54     return k->type;
55 }
56 
57 int tpm_backend_init(TPMBackend *s, TPMIf *tpmif, Error **errp)
58 {
59     if (s->tpmif) {
60         error_setg(errp, "TPM backend '%s' is already initialized", s->id);
61         return -1;
62     }
63 
64     s->tpmif = tpmif;
65     object_ref(OBJECT(tpmif));
66 
67     s->had_startup_error = false;
68 
69     return 0;
70 }
71 
72 int tpm_backend_startup_tpm(TPMBackend *s)
73 {
74     int res = 0;
75     TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
76 
77     /* terminate a running TPM */
78     tpm_backend_thread_end(s);
79 
80     s->thread_pool = g_thread_pool_new(tpm_backend_worker_thread, s, 1, TRUE,
81                                        NULL);
82 
83     res = k->startup_tpm ? k->startup_tpm(s) : 0;
84 
85     s->had_startup_error = (res != 0);
86 
87     return res;
88 }
89 
90 bool tpm_backend_had_startup_error(TPMBackend *s)
91 {
92     return s->had_startup_error;
93 }
94 
95 void tpm_backend_deliver_request(TPMBackend *s, TPMBackendCmd *cmd)
96 {
97     g_thread_pool_push(s->thread_pool, cmd, NULL);
98 }
99 
100 void tpm_backend_reset(TPMBackend *s)
101 {
102     TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
103 
104     if (k->reset) {
105         k->reset(s);
106     }
107 
108     tpm_backend_thread_end(s);
109 
110     s->had_startup_error = false;
111 }
112 
113 void tpm_backend_cancel_cmd(TPMBackend *s)
114 {
115     TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
116 
117     assert(k->cancel_cmd);
118 
119     k->cancel_cmd(s);
120 }
121 
122 bool tpm_backend_get_tpm_established_flag(TPMBackend *s)
123 {
124     TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
125 
126     return k->get_tpm_established_flag ?
127            k->get_tpm_established_flag(s) : false;
128 }
129 
130 int tpm_backend_reset_tpm_established_flag(TPMBackend *s, uint8_t locty)
131 {
132     TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
133 
134     return k->reset_tpm_established_flag ?
135            k->reset_tpm_established_flag(s, locty) : 0;
136 }
137 
138 TPMVersion tpm_backend_get_tpm_version(TPMBackend *s)
139 {
140     TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
141 
142     assert(k->get_tpm_version);
143 
144     return k->get_tpm_version(s);
145 }
146 
147 TPMInfo *tpm_backend_query_tpm(TPMBackend *s)
148 {
149     TPMInfo *info = g_new0(TPMInfo, 1);
150     TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
151     TPMIfClass *tic = TPM_IF_GET_CLASS(s->tpmif);
152 
153     info->id = g_strdup(s->id);
154     info->model = tic->model;
155     if (k->get_tpm_options) {
156         info->options = k->get_tpm_options(s);
157     }
158 
159     return info;
160 }
161 
162 static bool tpm_backend_prop_get_opened(Object *obj, Error **errp)
163 {
164     TPMBackend *s = TPM_BACKEND(obj);
165 
166     return s->opened;
167 }
168 
169 void tpm_backend_open(TPMBackend *s, Error **errp)
170 {
171     object_property_set_bool(OBJECT(s), true, "opened", errp);
172 }
173 
174 static void tpm_backend_prop_set_opened(Object *obj, bool value, Error **errp)
175 {
176     TPMBackend *s = TPM_BACKEND(obj);
177     TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
178     Error *local_err = NULL;
179 
180     if (value == s->opened) {
181         return;
182     }
183 
184     if (!value && s->opened) {
185         error_setg(errp, QERR_PERMISSION_DENIED);
186         return;
187     }
188 
189     if (k->opened) {
190         k->opened(s, &local_err);
191         if (local_err) {
192             error_propagate(errp, local_err);
193             return;
194         }
195     }
196 
197     s->opened = true;
198 }
199 
200 static void tpm_backend_instance_init(Object *obj)
201 {
202     TPMBackend *s = TPM_BACKEND(obj);
203 
204     object_property_add_bool(obj, "opened",
205                              tpm_backend_prop_get_opened,
206                              tpm_backend_prop_set_opened,
207                              NULL);
208     s->bh = qemu_bh_new(tpm_backend_request_completed_bh, s);
209 }
210 
211 static void tpm_backend_instance_finalize(Object *obj)
212 {
213     TPMBackend *s = TPM_BACKEND(obj);
214 
215     object_unref(OBJECT(s->tpmif));
216     g_free(s->id);
217     tpm_backend_thread_end(s);
218     qemu_bh_delete(s->bh);
219 }
220 
221 static const TypeInfo tpm_backend_info = {
222     .name = TYPE_TPM_BACKEND,
223     .parent = TYPE_OBJECT,
224     .instance_size = sizeof(TPMBackend),
225     .instance_init = tpm_backend_instance_init,
226     .instance_finalize = tpm_backend_instance_finalize,
227     .class_size = sizeof(TPMBackendClass),
228     .abstract = true,
229 };
230 
231 static const TypeInfo tpm_if_info = {
232     .name = TYPE_TPM_IF,
233     .parent = TYPE_INTERFACE,
234     .class_size = sizeof(TPMIfClass),
235 };
236 
237 static void register_types(void)
238 {
239     type_register_static(&tpm_backend_info);
240     type_register_static(&tpm_if_info);
241 }
242 
243 type_init(register_types);
244