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 #include "qom/object.h" 13 #include "sysemu/replay.h" 14 15 OBJECT_DECLARE_SIMPLE_TYPE(RngBuiltin, RNG_BUILTIN) 16 17 struct RngBuiltin { 18 RngBackend parent; 19 QEMUBH *bh; 20 }; 21 22 static void rng_builtin_receive_entropy_bh(void *opaque) 23 { 24 RngBuiltin *s = opaque; 25 26 while (!QSIMPLEQ_EMPTY(&s->parent.requests)) { 27 RngRequest *req = QSIMPLEQ_FIRST(&s->parent.requests); 28 29 qemu_guest_getrandom_nofail(req->data, req->size); 30 31 req->receive_entropy(req->opaque, req->data, req->size); 32 33 rng_backend_finalize_request(&s->parent, req); 34 } 35 } 36 37 static void rng_builtin_request_entropy(RngBackend *b, RngRequest *req) 38 { 39 RngBuiltin *s = RNG_BUILTIN(b); 40 41 replay_bh_schedule_event(s->bh); 42 } 43 44 static void rng_builtin_init(Object *obj) 45 { 46 RngBuiltin *s = RNG_BUILTIN(obj); 47 48 s->bh = qemu_bh_new(rng_builtin_receive_entropy_bh, s); 49 } 50 51 static void rng_builtin_finalize(Object *obj) 52 { 53 RngBuiltin *s = RNG_BUILTIN(obj); 54 55 qemu_bh_delete(s->bh); 56 } 57 58 static void rng_builtin_class_init(ObjectClass *klass, void *data) 59 { 60 RngBackendClass *rbc = RNG_BACKEND_CLASS(klass); 61 62 rbc->request_entropy = rng_builtin_request_entropy; 63 } 64 65 static const TypeInfo rng_builtin_info = { 66 .name = TYPE_RNG_BUILTIN, 67 .parent = TYPE_RNG_BACKEND, 68 .instance_size = sizeof(RngBuiltin), 69 .instance_init = rng_builtin_init, 70 .instance_finalize = rng_builtin_finalize, 71 .class_init = rng_builtin_class_init, 72 }; 73 74 static void register_types(void) 75 { 76 type_register_static(&rng_builtin_info); 77 } 78 79 type_init(register_types); 80