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