tpm.c

   1 /*
   2  * TPM configuration
   3  *
   4  * Copyright (C) 2011-2013 IBM Corporation
   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 net.c
  13  */
  14 #include "qemu/osdep.h"
  15
  16 #include "qapi/qmp/qerror.h"
  17 #include "sysemu/tpm_backend.h"
  18 #include "sysemu/tpm.h"
  19 #include "qemu/config-file.h"
  20 #include "qemu/error-report.h"
  21 #include "qmp-commands.h"
  22
  23 static QLIST_HEAD(, TPMBackend) tpm_backends =
  24     QLIST_HEAD_INITIALIZER(tpm_backends);
  25
  26
  27 #define TPM_MAX_MODELS      1
  28 #define TPM_MAX_DRIVERS     1
  29
  30 static TPMDriverOps const *be_drivers[TPM_MAX_DRIVERS] = {
  31     NULL,
  32 };
  33
  34 static enum TpmModel tpm_models[TPM_MAX_MODELS] = {
  35     TPM_MODEL__MAX,
  36 };
  37
  38 int tpm_register_model(enum TpmModel model)
  39 {
  40     int i;
  41
  42     for (i = 0; i < TPM_MAX_MODELS; i++) {
  43         if (tpm_models[i] == TPM_MODEL__MAX) {
  44             tpm_models[i] = model;
  45             return 0;
  46         }
  47     }
  48     error_report("Could not register TPM model");
  49     return 1;
  50 }
  51
  52 static bool tpm_model_is_registered(enum TpmModel model)
  53 {
  54     int i;
  55
  56     for (i = 0; i < TPM_MAX_MODELS; i++) {
  57         if (tpm_models[i] == model) {
  58             return true;
  59         }
  60     }
  61     return false;
  62 }
  63
  64 const TPMDriverOps *tpm_get_backend_driver(const char *type)
  65 {
  66     int i;
  67
  68     for (i = 0; i < TPM_MAX_DRIVERS && be_drivers[i] != NULL; i++) {
  69         if (!strcmp(TpmType_lookup[be_drivers[i]->type], type)) {
  70             return be_drivers[i];
  71         }
  72     }
  73
  74     return NULL;
  75 }
  76
  77 #ifdef CONFIG_TPM
  78
  79 int tpm_register_driver(const TPMDriverOps *tdo)
  80 {
  81     int i;
  82
  83     for (i = 0; i < TPM_MAX_DRIVERS; i++) {
  84         if (!be_drivers[i]) {
  85             be_drivers[i] = tdo;
  86             return 0;
  87         }
  88     }
  89     error_report("Could not register TPM driver");
  90     return 1;
  91 }
  92
  93 /*
  94  * Walk the list of available TPM backend drivers and display them on the
  95  * screen.
  96  */
  97 static void tpm_display_backend_drivers(void)
  98 {
  99     int i;
 100
 101     fprintf(stderr, "Supported TPM types (choose only one):\n");
 102
 103     for (i = 0; i < TPM_MAX_DRIVERS && be_drivers[i] != NULL; i++) {
 104         fprintf(stderr, "%12s   %s\n",
 105                 TpmType_lookup[be_drivers[i]->type], be_drivers[i]->desc());
 106     }
 107     fprintf(stderr, "\n");
 108 }
 109
 110 /*
 111  * Find the TPM with the given Id
 112  */
 113 TPMBackend *qemu_find_tpm(const char *id)
 114 {
 115     TPMBackend *drv;
 116
 117     if (id) {
 118         QLIST_FOREACH(drv, &tpm_backends, list) {
 119             if (!strcmp(drv->id, id)) {
 120                 return drv;
 121             }
 122         }
 123     }
 124
 125     return NULL;
 126 }
 127
 128 static int configure_tpm(QemuOpts *opts)
 129 {
 130     const char *value;
 131     const char *id;
 132     const TPMDriverOps *be;
 133     TPMBackend *drv;
 134     Error *local_err = NULL;
 135
 136     if (!QLIST_EMPTY(&tpm_backends)) {
 137         error_report("Only one TPM is allowed.");
 138         return 1;
 139     }
 140
 141     id = qemu_opts_id(opts);
 142     if (id == NULL) {
 143         error_report(QERR_MISSING_PARAMETER, "id");
 144         return 1;
 145     }
 146
 147     value = qemu_opt_get(opts, "type");
 148     if (!value) {
 149         error_report(QERR_MISSING_PARAMETER, "type");
 150         tpm_display_backend_drivers();
 151         return 1;
 152     }
 153
 154     be = tpm_get_backend_driver(value);
 155     if (be == NULL) {
 156         error_report(QERR_INVALID_PARAMETER_VALUE,
 157                      "type", "a TPM backend type");
 158         tpm_display_backend_drivers();
 159         return 1;
 160     }
 161
 162     /* validate backend specific opts */
 163     qemu_opts_validate(opts, be->opts, &local_err);
 164     if (local_err) {
 165         error_report_err(local_err);
 166         return 1;
 167     }
 168
 169     drv = be->create(opts, id);
 170     if (!drv) {
 171         return 1;
 172     }
 173
 174     tpm_backend_open(drv, &local_err);
 175     if (local_err) {
 176         error_report_err(local_err);
 177         return 1;
 178     }
 179
 180     QLIST_INSERT_HEAD(&tpm_backends, drv, list);
 181
 182     return 0;
 183 }
 184
 185 static int tpm_init_tpmdev(void *dummy, QemuOpts *opts, Error **errp)
 186 {
 187     return configure_tpm(opts);
 188 }
 189
 190 /*
 191  * Walk the list of TPM backend drivers that are in use and call their
 192  * destroy function to have them cleaned up.
 193  */
 194 void tpm_cleanup(void)
 195 {
 196     TPMBackend *drv, *next;
 197
 198     QLIST_FOREACH_SAFE(drv, &tpm_backends, list, next) {
 199         QLIST_REMOVE(drv, list);
 200         tpm_backend_destroy(drv);
 201     }
 202 }
 203
 204 /*
 205  * Initialize the TPM. Process the tpmdev command line options describing the
 206  * TPM backend.
 207  */
 208 int tpm_init(void)
 209 {
 210     if (qemu_opts_foreach(qemu_find_opts("tpmdev"),
 211                           tpm_init_tpmdev, NULL, NULL)) {
 212         return -1;
 213     }
 214
 215     atexit(tpm_cleanup);
 216     return 0;
 217 }
 218
 219 /*
 220  * Parse the TPM configuration options.
 221  * To display all available TPM backends the user may use '-tpmdev help'
 222  */
 223 int tpm_config_parse(QemuOptsList *opts_list, const char *optarg)
 224 {
 225     QemuOpts *opts;
 226
 227     if (!strcmp(optarg, "help")) {
 228         tpm_display_backend_drivers();
 229         return -1;
 230     }
 231     opts = qemu_opts_parse_noisily(opts_list, optarg, true);
 232     if (!opts) {
 233         return -1;
 234     }
 235     return 0;
 236 }
 237
 238 #endif /* CONFIG_TPM */
 239
 240 static const TPMDriverOps *tpm_driver_find_by_type(enum TpmType type)
 241 {
 242     int i;
 243
 244     for (i = 0; i < TPM_MAX_DRIVERS && be_drivers[i] != NULL; i++) {
 245         if (be_drivers[i]->type == type) {
 246             return be_drivers[i];
 247         }
 248     }
 249     return NULL;
 250 }
 251
 252 static TPMInfo *qmp_query_tpm_inst(TPMBackend *drv)
 253 {
 254     TPMInfo *res = g_new0(TPMInfo, 1);
 255     TPMPassthroughOptions *tpo;
 256
 257     res->id = g_strdup(drv->id);
 258     res->model = drv->fe_model;
 259     res->options = g_new0(TpmTypeOptions, 1);
 260
 261     switch (drv->ops->type) {
 262     case TPM_TYPE_PASSTHROUGH:
 263         res->options->type = TPM_TYPE_OPTIONS_KIND_PASSTHROUGH;
 264         tpo = g_new0(TPMPassthroughOptions, 1);
 265         res->options->u.passthrough.data = tpo;
 266         if (drv->path) {
 267             tpo->path = g_strdup(drv->path);
 268             tpo->has_path = true;
 269         }
 270         if (drv->cancel_path) {
 271             tpo->cancel_path = g_strdup(drv->cancel_path);
 272             tpo->has_cancel_path = true;
 273         }
 274         break;
 275     case TPM_TYPE__MAX:
 276         break;
 277     }
 278
 279     return res;
 280 }
 281
 282 /*
 283  * Walk the list of active TPM backends and collect information about them
 284  * following the schema description in qapi-schema.json.
 285  */
 286 TPMInfoList *qmp_query_tpm(Error **errp)
 287 {
 288     TPMBackend *drv;
 289     TPMInfoList *info, *head = NULL, *cur_item = NULL;
 290
 291     QLIST_FOREACH(drv, &tpm_backends, list) {
 292         if (!tpm_model_is_registered(drv->fe_model)) {
 293             continue;
 294         }
 295         info = g_new0(TPMInfoList, 1);
 296         info->value = qmp_query_tpm_inst(drv);
 297
 298         if (!cur_item) {
 299             head = cur_item = info;
 300         } else {
 301             cur_item->next = info;
 302             cur_item = info;
 303         }
 304     }
 305
 306     return head;
 307 }
 308
 309 TpmTypeList *qmp_query_tpm_types(Error **errp)
 310 {
 311     unsigned int i = 0;
 312     TpmTypeList *head = NULL, *prev = NULL, *cur_item;
 313
 314     for (i = 0; i < TPM_TYPE__MAX; i++) {
 315         if (!tpm_driver_find_by_type(i)) {
 316             continue;
 317         }
 318         cur_item = g_new0(TpmTypeList, 1);
 319         cur_item->value = i;
 320
 321         if (prev) {
 322             prev->next = cur_item;
 323         }
 324         if (!head) {
 325             head = cur_item;
 326         }
 327         prev = cur_item;
 328     }
 329
 330     return head;
 331 }
 332
 333 TpmModelList *qmp_query_tpm_models(Error **errp)
 334 {
 335     unsigned int i = 0;
 336     TpmModelList *head = NULL, *prev = NULL, *cur_item;
 337
 338     for (i = 0; i < TPM_MODEL__MAX; i++) {
 339         if (!tpm_model_is_registered(i)) {
 340             continue;
 341         }
 342         cur_item = g_new0(TpmModelList, 1);
 343         cur_item->value = i;
 344
 345         if (prev) {
 346             prev->next = cur_item;
 347         }
 348         if (!head) {
 349             head = cur_item;
 350         }
 351         prev = cur_item;
 352     }
 353
 354     return head;
 355 }