1 | /* |
2 | * QEMU Random Number Generator Backend |
3 | * |
4 | * Copyright IBM, Corp. 2012 |
5 | * |
6 | * Authors: |
7 | * Anthony Liguori <aliguori@us.ibm.com> |
8 | * |
9 | * This work is licensed under the terms of the GNU GPL, version 2 or later. |
10 | * See the COPYING file in the top-level directory. |
11 | */ |
12 | |
13 | #include "qemu/osdep.h" |
14 | #include "sysemu/rng.h" |
15 | #include "qapi/error.h" |
16 | #include "qapi/qmp/qerror.h" |
17 | #include "qemu/module.h" |
18 | #include "qom/object_interfaces.h" |
19 | |
20 | void rng_backend_request_entropy(RngBackend *s, size_t size, |
21 | EntropyReceiveFunc *receive_entropy, |
22 | void *opaque) |
23 | { |
24 | RngBackendClass *k = RNG_BACKEND_GET_CLASS(s); |
25 | RngRequest *req; |
26 | |
27 | if (k->request_entropy) { |
28 | req = g_malloc(sizeof(*req)); |
29 | |
30 | req->offset = 0; |
31 | req->size = size; |
32 | req->receive_entropy = receive_entropy; |
33 | req->opaque = opaque; |
34 | req->data = g_malloc(req->size); |
35 | |
36 | k->request_entropy(s, req); |
37 | |
38 | QSIMPLEQ_INSERT_TAIL(&s->requests, req, next); |
39 | } |
40 | } |
41 | |
42 | static bool rng_backend_prop_get_opened(Object *obj, Error **errp) |
43 | { |
44 | RngBackend *s = RNG_BACKEND(obj); |
45 | |
46 | return s->opened; |
47 | } |
48 | |
49 | static void rng_backend_complete(UserCreatable *uc, Error **errp) |
50 | { |
51 | object_property_set_bool(OBJECT(uc), true, "opened" , errp); |
52 | } |
53 | |
54 | static void rng_backend_prop_set_opened(Object *obj, bool value, Error **errp) |
55 | { |
56 | RngBackend *s = RNG_BACKEND(obj); |
57 | RngBackendClass *k = RNG_BACKEND_GET_CLASS(s); |
58 | Error *local_err = NULL; |
59 | |
60 | if (value == s->opened) { |
61 | return; |
62 | } |
63 | |
64 | if (!value && s->opened) { |
65 | error_setg(errp, QERR_PERMISSION_DENIED); |
66 | return; |
67 | } |
68 | |
69 | if (k->opened) { |
70 | k->opened(s, &local_err); |
71 | if (local_err) { |
72 | error_propagate(errp, local_err); |
73 | return; |
74 | } |
75 | } |
76 | |
77 | s->opened = true; |
78 | } |
79 | |
80 | static void rng_backend_free_request(RngRequest *req) |
81 | { |
82 | g_free(req->data); |
83 | g_free(req); |
84 | } |
85 | |
86 | static void rng_backend_free_requests(RngBackend *s) |
87 | { |
88 | RngRequest *req, *next; |
89 | |
90 | QSIMPLEQ_FOREACH_SAFE(req, &s->requests, next, next) { |
91 | rng_backend_free_request(req); |
92 | } |
93 | |
94 | QSIMPLEQ_INIT(&s->requests); |
95 | } |
96 | |
97 | void rng_backend_finalize_request(RngBackend *s, RngRequest *req) |
98 | { |
99 | QSIMPLEQ_REMOVE(&s->requests, req, RngRequest, next); |
100 | rng_backend_free_request(req); |
101 | } |
102 | |
103 | static void rng_backend_init(Object *obj) |
104 | { |
105 | RngBackend *s = RNG_BACKEND(obj); |
106 | |
107 | QSIMPLEQ_INIT(&s->requests); |
108 | |
109 | object_property_add_bool(obj, "opened" , |
110 | rng_backend_prop_get_opened, |
111 | rng_backend_prop_set_opened, |
112 | NULL); |
113 | } |
114 | |
115 | static void rng_backend_finalize(Object *obj) |
116 | { |
117 | RngBackend *s = RNG_BACKEND(obj); |
118 | |
119 | rng_backend_free_requests(s); |
120 | } |
121 | |
122 | static void rng_backend_class_init(ObjectClass *oc, void *data) |
123 | { |
124 | UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc); |
125 | |
126 | ucc->complete = rng_backend_complete; |
127 | } |
128 | |
129 | static const TypeInfo rng_backend_info = { |
130 | .name = TYPE_RNG_BACKEND, |
131 | .parent = TYPE_OBJECT, |
132 | .instance_size = sizeof(RngBackend), |
133 | .instance_init = rng_backend_init, |
134 | .instance_finalize = rng_backend_finalize, |
135 | .class_size = sizeof(RngBackendClass), |
136 | .class_init = rng_backend_class_init, |
137 | .abstract = true, |
138 | .interfaces = (InterfaceInfo[]) { |
139 | { TYPE_USER_CREATABLE }, |
140 | { } |
141 | } |
142 | }; |
143 | |
144 | static void register_types(void) |
145 | { |
146 | type_register_static(&rng_backend_info); |
147 | } |
148 | |
149 | type_init(register_types); |
150 | |