system/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
  15 #include "qemu/osdep.h"
  16
  17 #include "qapi/error.h"
  18 #include "qapi/qapi-commands-tpm.h"
  19 #include "qapi/qmp/qerror.h"
  20 #include "sysemu/tpm_backend.h"
  21 #include "sysemu/tpm.h"
  22 #include "qemu/config-file.h"
  23 #include "qemu/error-report.h"
  24
  25 static QLIST_HEAD(, TPMBackend) tpm_backends =
  26     QLIST_HEAD_INITIALIZER(tpm_backends);
  27
  28 static const TPMBackendClass *
  29 tpm_be_find_by_type(enum TpmType type)
  30 {
  31     ObjectClass *oc;
  32     char *typename = g_strdup_printf("tpm-%s", TpmType_str(type));
  33
  34     oc = object_class_by_name(typename);
  35     g_free(typename);
  36
  37     if (!object_class_dynamic_cast(oc, TYPE_TPM_BACKEND)) {
  38         return NULL;
  39     }
  40
  41     return TPM_BACKEND_CLASS(oc);
  42 }
  43
  44 /*
  45  * Walk the list of available TPM backend drivers and display them on the
  46  * screen.
  47  */
  48 static void tpm_display_backend_drivers(void)
  49 {
  50     bool got_one = false;
  51     int i;
  52
  53     for (i = 0; i < TPM_TYPE__MAX; i++) {
  54         const TPMBackendClass *bc = tpm_be_find_by_type(i);
  55         if (!bc) {
  56             continue;
  57         }
  58         if (!got_one) {
  59             error_printf("Supported TPM types (choose only one):\n");
  60             got_one = true;
  61         }
  62         error_printf("%12s   %s\n", TpmType_str(i), bc->desc);
  63     }
  64     if (!got_one) {
  65         error_printf("No TPM backend types are available\n");
  66     }
  67 }
  68
  69 /*
  70  * Find the TPM with the given Id
  71  */
  72 TPMBackend *qemu_find_tpm_be(const char *id)
  73 {
  74     TPMBackend *drv;
  75
  76     if (id) {
  77         QLIST_FOREACH(drv, &tpm_backends, list) {
  78             if (!strcmp(drv->id, id)) {
  79                 return drv;
  80             }
  81         }
  82     }
  83
  84     return NULL;
  85 }
  86
  87 static int tpm_init_tpmdev(void *dummy, QemuOpts *opts, Error **errp)
  88 {
  89     /*
  90      * Use of error_report() in a function with an Error ** parameter
  91      * is suspicious.  It is okay here.  The parameter only exists to
  92      * make the function usable with qemu_opts_foreach().  It is not
  93      * actually used.
  94      */
  95     const char *value;
  96     const char *id;
  97     const TPMBackendClass *be;
  98     TPMBackend *drv;
  99     Error *local_err = NULL;
 100     int i;
 101
 102     if (!QLIST_EMPTY(&tpm_backends)) {
 103         error_report("Only one TPM is allowed.");
 104         return 1;
 105     }
 106
 107     id = qemu_opts_id(opts);
 108     if (id == NULL) {
 109         error_report(QERR_MISSING_PARAMETER, "id");
 110         return 1;
 111     }
 112
 113     value = qemu_opt_get(opts, "type");
 114     if (!value) {
 115         error_report(QERR_MISSING_PARAMETER, "type");
 116         tpm_display_backend_drivers();
 117         return 1;
 118     }
 119
 120     i = qapi_enum_parse(&TpmType_lookup, value, -1, NULL);
 121     be = i >= 0 ? tpm_be_find_by_type(i) : NULL;
 122     if (be == NULL) {
 123         error_report(QERR_INVALID_PARAMETER_VALUE,
 124                      "type", "a TPM backend type");
 125         tpm_display_backend_drivers();
 126         return 1;
 127     }
 128
 129     /* validate backend specific opts */
 130     if (!qemu_opts_validate(opts, be->opts, &local_err)) {
 131         error_report_err(local_err);
 132         return 1;
 133     }
 134
 135     drv = be->create(opts);
 136     if (!drv) {
 137         return 1;
 138     }
 139
 140     drv->id = g_strdup(id);
 141     QLIST_INSERT_HEAD(&tpm_backends, drv, list);
 142
 143     return 0;
 144 }
 145
 146 /*
 147  * Walk the list of TPM backend drivers that are in use and call their
 148  * destroy function to have them cleaned up.
 149  */
 150 void tpm_cleanup(void)
 151 {
 152     TPMBackend *drv, *next;
 153
 154     QLIST_FOREACH_SAFE(drv, &tpm_backends, list, next) {
 155         QLIST_REMOVE(drv, list);
 156         object_unref(OBJECT(drv));
 157     }
 158 }
 159
 160 /*
 161  * Initialize the TPM. Process the tpmdev command line options describing the
 162  * TPM backend.
 163  */
 164 int tpm_init(void)
 165 {
 166     if (qemu_opts_foreach(qemu_find_opts("tpmdev"),
 167                           tpm_init_tpmdev, NULL, NULL)) {
 168         return -1;
 169     }
 170
 171     return 0;
 172 }
 173
 174 /*
 175  * Parse the TPM configuration options.
 176  * To display all available TPM backends the user may use '-tpmdev help'
 177  */
 178 int tpm_config_parse(QemuOptsList *opts_list, const char *optstr)
 179 {
 180     QemuOpts *opts;
 181
 182     if (!strcmp(optstr, "help")) {
 183         tpm_display_backend_drivers();
 184         return -1;
 185     }
 186     opts = qemu_opts_parse_noisily(opts_list, optstr, true);
 187     if (!opts) {
 188         return -1;
 189     }
 190     return 0;
 191 }
 192
 193 /*
 194  * Walk the list of active TPM backends and collect information about them.
 195  */
 196 TPMInfoList *qmp_query_tpm(Error **errp)
 197 {
 198     TPMBackend *drv;
 199     TPMInfoList *head = NULL, **tail = &head;
 200
 201     QLIST_FOREACH(drv, &tpm_backends, list) {
 202         if (!drv->tpmif) {
 203             continue;
 204         }
 205
 206         QAPI_LIST_APPEND(tail, tpm_backend_query_tpm(drv));
 207     }
 208
 209     return head;
 210 }
 211
 212 TpmTypeList *qmp_query_tpm_types(Error **errp)
 213 {
 214     unsigned int i = 0;
 215     TpmTypeList *head = NULL, **tail = &head;
 216
 217     for (i = 0; i < TPM_TYPE__MAX; i++) {
 218         if (!tpm_be_find_by_type(i)) {
 219             continue;
 220         }
 221         QAPI_LIST_APPEND(tail, i);
 222     }
 223
 224     return head;
 225 }
 226 TpmModelList *qmp_query_tpm_models(Error **errp)
 227 {
 228     TpmModelList *head = NULL, **tail = &head;
 229     GSList *e, *l = object_class_get_list(TYPE_TPM_IF, false);
 230
 231     for (e = l; e; e = e->next) {
 232         TPMIfClass *c = TPM_IF_CLASS(e->data);
 233
 234         QAPI_LIST_APPEND(tail, c->model);
 235     }
 236     g_slist_free(l);
 237
 238     return head;
 239 }