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 15 typedef struct RngBuiltin { 16 RngBackend parent; 17 QEMUBH *bh; 18 } RngBuiltin; 19 20 static 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 35 static 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 42 static 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 49 static void rng_builtin_finalize(Object *obj) 50 { 51 RngBuiltin *s = RNG_BUILTIN(obj); 52 53 qemu_bh_delete(s->bh); 54 } 55 56 static 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 63 static 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 72 static void register_types(void) 73 { 74 type_register_static(&rng_builtin_info); 75 } 76 77 type_init(register_types); 78