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 | |