LXR qemu/backends/rng-builtin.c

   1/*
   2 * QEMU Builtin Random Number Generator Backend
   3 *
   4 * This work is licensed under the terms of the GNU GPL, version 2 or later.
   5 * See the COPYING file in the top-level directory.
   6 */
   7
   8#include "qemu/osdep.h"
   9#include "sysemu/rng.h"
  10#include "qemu/main-loop.h"
  11#include "qemu/guest-random.h"
  12
  13#define RNG_BUILTIN(obj) OBJECT_CHECK(RngBuiltin, (obj), TYPE_RNG_BUILTIN)
  14
  15typedef struct RngBuiltin {
  16    RngBackend parent;
  17    QEMUBH *bh;
  18} RngBuiltin;
  19
  20static void rng_builtin_receive_entropy_bh(void *opaque)
  21{
  22    RngBuiltin *s = opaque;
  23
  24    while (!QSIMPLEQ_EMPTY(&s->parent.requests)) {
  25        RngRequest *req = QSIMPLEQ_FIRST(&s->parent.requests);
  26
  27        qemu_guest_getrandom_nofail(req->data, req->size);
  28
  29        req->receive_entropy(req->opaque, req->data, req->size);
  30
  31        rng_backend_finalize_request(&s->parent, req);
  32    }
  33}
  34
  35static void rng_builtin_request_entropy(RngBackend *b, RngRequest *req)
  36{
  37    RngBuiltin *s = RNG_BUILTIN(b);
  38
  39    qemu_bh_schedule(s->bh);
  40}
  41
  42static void rng_builtin_init(Object *obj)
  43{
  44    RngBuiltin *s = RNG_BUILTIN(obj);
  45
  46    s->bh = qemu_bh_new(rng_builtin_receive_entropy_bh, s);
  47}
  48
  49static void rng_builtin_finalize(Object *obj)
  50{
  51    RngBuiltin *s = RNG_BUILTIN(obj);
  52
  53    qemu_bh_delete(s->bh);
  54}
  55
  56static void rng_builtin_class_init(ObjectClass *klass, void *data)
  57{
  58    RngBackendClass *rbc = RNG_BACKEND_CLASS(klass);
  59
  60    rbc->request_entropy = rng_builtin_request_entropy;
  61}
  62
  63static const TypeInfo rng_builtin_info = {
  64    .name = TYPE_RNG_BUILTIN,
  65    .parent = TYPE_RNG_BACKEND,
  66    .instance_size = sizeof(RngBuiltin),
  67    .instance_init = rng_builtin_init,
  68    .instance_finalize = rng_builtin_finalize,
  69    .class_init = rng_builtin_class_init,
  70};
  71
  72static void register_types(void)
  73{
  74    type_register_static(&rng_builtin_info);
  75}
  76
  77type_init(register_types);
  78