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 static TPMDriverOps const *be_drivers[TPM_TYPE__MAX];
  27 static bool tpm_models[TPM_MODEL__MAX];
  28
  29 void tpm_register_model(enum TpmModel model)
  30 {
  31     tpm_models[model] = true;
  32 }
  33
  34 const TPMDriverOps *tpm_get_backend_driver(const char *type)
  35 {
  36     int i = qapi_enum_parse(&TpmType_lookup, type, -1, NULL);
  37
  38     return i >= 0 ? be_drivers[i] : NULL;
  39 }
  40
  41 #ifdef CONFIG_TPM
  42
  43 void tpm_register_driver(const TPMDriverOps *tdo)
  44 {
  45     assert(!be_drivers[tdo->type]);
  46
  47     be_drivers[tdo->type] = tdo;
  48 }
  49
  50 /*
  51  * Walk the list of available TPM backend drivers and display them on the
  52  * screen.
  53  */
  54 static void tpm_display_backend_drivers(void)
  55 {
  56     int i;
  57
  58     fprintf(stderr, "Supported TPM types (choose only one):\n");
  59
  60     for (i = 0; i < TPM_TYPE__MAX; i++) {
  61         if (be_drivers[i] == NULL) {
  62             continue;
  63         }
  64         fprintf(stderr, "%12s   %s\n",
  65                 TpmType_str(i), be_drivers[i]->desc());
  66     }
  67     fprintf(stderr, "\n");
  68 }
  69
  70 /*
  71  * Find the TPM with the given Id
  72  */
  73 TPMBackend *qemu_find_tpm(const char *id)
  74 {
  75     TPMBackend *drv;
  76
  77     if (id) {
  78         QLIST_FOREACH(drv, &tpm_backends, list) {
  79             if (!strcmp(drv->id, id)) {
  80                 return drv;
  81             }
  82         }
  83     }
  84
  85     return NULL;
  86 }
  87
  88 static int configure_tpm(QemuOpts *opts)
  89 {
  90     const char *value;
  91     const char *id;
  92     const TPMDriverOps *be;
  93     TPMBackend *drv;
  94     Error *local_err = NULL;
  95
  96     if (!QLIST_EMPTY(&tpm_backends)) {
  97         error_report("Only one TPM is allowed.");
  98         return 1;
  99     }
 100
 101     id = qemu_opts_id(opts);
 102     if (id == NULL) {
 103         error_report(QERR_MISSING_PARAMETER, "id");
 104         return 1;
 105     }
 106
 107     value = qemu_opt_get(opts, "type");
 108     if (!value) {
 109         error_report(QERR_MISSING_PARAMETER, "type");
 110         tpm_display_backend_drivers();
 111         return 1;
 112     }
 113
 114     be = tpm_get_backend_driver(value);
 115     if (be == NULL) {
 116         error_report(QERR_INVALID_PARAMETER_VALUE,
 117                      "type", "a TPM backend type");
 118         tpm_display_backend_drivers();
 119         return 1;
 120     }
 121
 122     /* validate backend specific opts */
 123     qemu_opts_validate(opts, be->opts, &local_err);
 124     if (local_err) {
 125         error_report_err(local_err);
 126         return 1;
 127     }
 128
 129     drv = be->create(opts, id);
 130     if (!drv) {
 131         return 1;
 132     }
 133
 134     tpm_backend_open(drv, &local_err);
 135     if (local_err) {
 136         error_report_err(local_err);
 137         return 1;
 138     }
 139
 140     QLIST_INSERT_HEAD(&tpm_backends, drv, list);
 141
 142     return 0;
 143 }
 144
 145 static int tpm_init_tpmdev(void *dummy, QemuOpts *opts, Error **errp)
 146 {
 147     return configure_tpm(opts);
 148 }
 149
 150 /*
 151  * Walk the list of TPM backend drivers that are in use and call their
 152  * destroy function to have them cleaned up.
 153  */
 154 void tpm_cleanup(void)
 155 {
 156     TPMBackend *drv, *next;
 157
 158     QLIST_FOREACH_SAFE(drv, &tpm_backends, list, next) {
 159         QLIST_REMOVE(drv, list);
 160         tpm_backend_destroy(drv);
 161     }
 162 }
 163
 164 /*
 165  * Initialize the TPM. Process the tpmdev command line options describing the
 166  * TPM backend.
 167  */
 168 int tpm_init(void)
 169 {
 170     if (qemu_opts_foreach(qemu_find_opts("tpmdev"),
 171                           tpm_init_tpmdev, NULL, NULL)) {
 172         return -1;
 173     }
 174
 175     atexit(tpm_cleanup);
 176     return 0;
 177 }
 178
 179 /*
 180  * Parse the TPM configuration options.
 181  * To display all available TPM backends the user may use '-tpmdev help'
 182  */
 183 int tpm_config_parse(QemuOptsList *opts_list, const char *optarg)
 184 {
 185     QemuOpts *opts;
 186
 187     if (!strcmp(optarg, "help")) {
 188         tpm_display_backend_drivers();
 189         return -1;
 190     }
 191     opts = qemu_opts_parse_noisily(opts_list, optarg, true);
 192     if (!opts) {
 193         return -1;
 194     }
 195     return 0;
 196 }
 197
 198 #endif /* CONFIG_TPM */
 199
 200 static const TPMDriverOps *tpm_driver_find_by_type(enum TpmType type)
 201 {
 202     return be_drivers[type];
 203 }
 204
 205 static TPMInfo *qmp_query_tpm_inst(TPMBackend *drv)
 206 {
 207     TPMInfo *res = g_new0(TPMInfo, 1);
 208     TPMPassthroughOptions *tpo;
 209
 210     res->id = g_strdup(drv->id);
 211     res->model = drv->fe_model;
 212     res->options = g_new0(TpmTypeOptions, 1);
 213
 214     switch (drv->ops->type) {
 215     case TPM_TYPE_PASSTHROUGH:
 216         res->options->type = TPM_TYPE_OPTIONS_KIND_PASSTHROUGH;
 217         tpo = g_new0(TPMPassthroughOptions, 1);
 218         res->options->u.passthrough.data = tpo;
 219         if (drv->path) {
 220             tpo->path = g_strdup(drv->path);
 221             tpo->has_path = true;
 222         }
 223         if (drv->cancel_path) {
 224             tpo->cancel_path = g_strdup(drv->cancel_path);
 225             tpo->has_cancel_path = true;
 226         }
 227         break;
 228     case TPM_TYPE__MAX:
 229         break;
 230     }
 231
 232     return res;
 233 }
 234
 235 /*
 236  * Walk the list of active TPM backends and collect information about them
 237  * following the schema description in qapi-schema.json.
 238  */
 239 TPMInfoList *qmp_query_tpm(Error **errp)
 240 {
 241     TPMBackend *drv;
 242     TPMInfoList *info, *head = NULL, *cur_item = NULL;
 243
 244     QLIST_FOREACH(drv, &tpm_backends, list) {
 245         if (!tpm_models[drv->fe_model]) {
 246             continue;
 247         }
 248         info = g_new0(TPMInfoList, 1);
 249         info->value = qmp_query_tpm_inst(drv);
 250
 251         if (!cur_item) {
 252             head = cur_item = info;
 253         } else {
 254             cur_item->next = info;
 255             cur_item = info;
 256         }
 257     }
 258
 259     return head;
 260 }
 261
 262 TpmTypeList *qmp_query_tpm_types(Error **errp)
 263 {
 264     unsigned int i = 0;
 265     TpmTypeList *head = NULL, *prev = NULL, *cur_item;
 266
 267     for (i = 0; i < TPM_TYPE__MAX; i++) {
 268         if (!tpm_driver_find_by_type(i)) {
 269             continue;
 270         }
 271         cur_item = g_new0(TpmTypeList, 1);
 272         cur_item->value = i;
 273
 274         if (prev) {
 275             prev->next = cur_item;
 276         }
 277         if (!head) {
 278             head = cur_item;
 279         }
 280         prev = cur_item;
 281     }
 282
 283     return head;
 284 }
 285
 286 TpmModelList *qmp_query_tpm_models(Error **errp)
 287 {
 288     unsigned int i = 0;
 289     TpmModelList *head = NULL, *prev = NULL, *cur_item;
 290
 291     for (i = 0; i < TPM_MODEL__MAX; i++) {
 292         if (!tpm_models[i]) {
 293             continue;
 294         }
 295         cur_item = g_new0(TpmModelList, 1);
 296         cur_item->value = i;
 297
 298         if (prev) {
 299             prev->next = cur_item;
 300         }
 301         if (!head) {
 302             head = cur_item;
 303         }
 304         prev = cur_item;
 305     }
 306
 307     return head;
 308 }