xref: /openbmc/qemu/include/sysemu/tpm_backend.h (revision dccfcd0e)
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 
13 #ifndef _QEMU_TPM_H
14 #define _QEMU_TPM_H
15 
16 #include "qom/object.h"
17 #include "qemu-common.h"
18 #include "qapi/error.h"
19 #include "qapi-types.h"
20 #include "qemu/option.h"
21 #include "sysemu/tpm.h"
22 
23 #define TYPE_TPM_BACKEND "tpm-backend"
24 #define TPM_BACKEND(obj) \
25     OBJECT_CHECK(TPMBackend, (obj), TYPE_TPM_BACKEND)
26 #define TPM_BACKEND_GET_CLASS(obj) \
27     OBJECT_GET_CLASS(TPMBackendClass, (obj), TYPE_TPM_BACKEND)
28 #define TPM_BACKEND_CLASS(klass) \
29     OBJECT_CLASS_CHECK(TPMBackendClass, (klass), TYPE_TPM_BACKEND)
30 
31 typedef struct TPMBackendClass TPMBackendClass;
32 typedef struct TPMBackend TPMBackend;
33 
34 typedef struct TPMDriverOps TPMDriverOps;
35 
36 struct TPMBackendClass {
37     ObjectClass parent_class;
38 
39     const TPMDriverOps *ops;
40 
41     void (*opened)(TPMBackend *s, Error **errp);
42 };
43 
44 struct TPMBackend {
45     Object parent;
46 
47     /*< protected >*/
48     bool opened;
49 
50     char *id;
51     enum TpmModel fe_model;
52     char *path;
53     char *cancel_path;
54     const TPMDriverOps *ops;
55 
56     QLIST_ENTRY(TPMBackend) list;
57 };
58 
59 typedef void (TPMRecvDataCB)(TPMState *, uint8_t locty);
60 
61 typedef struct TPMSizedBuffer {
62     uint32_t size;
63     uint8_t  *buffer;
64 } TPMSizedBuffer;
65 
66 struct TPMDriverOps {
67     enum TpmType type;
68     /* get a descriptive text of the backend to display to the user */
69     const char *(*desc)(void);
70 
71     TPMBackend *(*create)(QemuOpts *opts, const char *id);
72     void (*destroy)(TPMBackend *t);
73 
74     /* initialize the backend */
75     int (*init)(TPMBackend *t, TPMState *s, TPMRecvDataCB *datacb);
76     /* start up the TPM on the backend */
77     int (*startup_tpm)(TPMBackend *t);
78     /* returns true if nothing will ever answer TPM requests */
79     bool (*had_startup_error)(TPMBackend *t);
80 
81     size_t (*realloc_buffer)(TPMSizedBuffer *sb);
82 
83     void (*deliver_request)(TPMBackend *t);
84 
85     void (*reset)(TPMBackend *t);
86 
87     void (*cancel_cmd)(TPMBackend *t);
88 
89     bool (*get_tpm_established_flag)(TPMBackend *t);
90 };
91 
92 
93 /**
94  * tpm_backend_get_type:
95  * @s: the backend
96  *
97  * Returns the TpmType of the backend.
98  */
99 enum TpmType tpm_backend_get_type(TPMBackend *s);
100 
101 /**
102  * tpm_backend_get_desc:
103  * @s: the backend
104  *
105  * Returns a human readable description of the backend.
106  */
107 const char *tpm_backend_get_desc(TPMBackend *s);
108 
109 /**
110  * tpm_backend_destroy:
111  * @s: the backend to destroy
112  */
113 void tpm_backend_destroy(TPMBackend *s);
114 
115 /**
116  * tpm_backend_init:
117  * @s: the backend to initialized
118  * @state: TPMState
119  * @datacb: callback for sending data to frontend
120  *
121  * Initialize the backend with the given variables.
122  *
123  * Returns 0 on success.
124  */
125 int tpm_backend_init(TPMBackend *s, TPMState *state,
126                      TPMRecvDataCB *datacb);
127 
128 /**
129  * tpm_backend_startup_tpm:
130  * @s: the backend whose TPM support is to be started
131  *
132  * Returns 0 on success.
133  */
134 int tpm_backend_startup_tpm(TPMBackend *s);
135 
136 /**
137  * tpm_backend_had_startup_error:
138  * @s: the backend to query for a statup error
139  *
140  * Check whether the backend had an error during startup. Returns
141  * false if no error occurred and the backend can be used, true
142  * otherwise.
143  */
144 bool tpm_backend_had_startup_error(TPMBackend *s);
145 
146 /**
147  * tpm_backend_realloc_buffer:
148  * @s: the backend
149  * @sb: the TPMSizedBuffer to re-allocated to the size suitable for the
150  *      backend.
151  *
152  * This function returns the size of the allocated buffer
153  */
154 size_t tpm_backend_realloc_buffer(TPMBackend *s, TPMSizedBuffer *sb);
155 
156 /**
157  * tpm_backend_deliver_request:
158  * @s: the backend to send the request to
159  *
160  * Send a request to the backend. The backend will then send the request
161  * to the TPM implementation.
162  */
163 void tpm_backend_deliver_request(TPMBackend *s);
164 
165 /**
166  * tpm_backend_reset:
167  * @s: the backend to reset
168  *
169  * Reset the backend into a well defined state with all previous errors
170  * reset.
171  */
172 void tpm_backend_reset(TPMBackend *s);
173 
174 /**
175  * tpm_backend_cancel_cmd:
176  * @s: the backend
177  *
178  * Cancel any ongoing command being processed by the TPM implementation
179  * on behalf of the QEMU guest.
180  */
181 void tpm_backend_cancel_cmd(TPMBackend *s);
182 
183 /**
184  * tpm_backend_get_tpm_established_flag:
185  * @s: the backend
186  *
187  * Get the TPM establishment flag. This function may be called very
188  * frequently by the frontend since for example in the TIS implementation
189  * this flag is part of a register.
190  */
191 bool tpm_backend_get_tpm_established_flag(TPMBackend *s);
192 
193 /**
194  * tpm_backend_open:
195  * @s: the backend to open
196  * @errp: a pointer to return the #Error object if an error occurs.
197  *
198  * This function will open the backend if it is not already open.  Calling this
199  * function on an already opened backend will not result in an error.
200  */
201 void tpm_backend_open(TPMBackend *s, Error **errp);
202 
203 TPMBackend *qemu_find_tpm(const char *id);
204 
205 const TPMDriverOps *tpm_get_backend_driver(const char *type);
206 int tpm_register_model(enum TpmModel model);
207 int tpm_register_driver(const TPMDriverOps *tdo);
208 
209 #endif
210