Merge tag 'block-pull-request' of https://gitlab.com/stefanha/qemu into staging
[qemu.git] / crypto / pbkdf.c
1 /*
2 * QEMU Crypto PBKDF support (Password-Based Key Derivation Function)
3 *
4 * Copyright (c) 2015-2016 Red Hat, Inc.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 *
19 */
20
21 #include "qemu/osdep.h"
22 #include "qapi/error.h"
23 #include "crypto/pbkdf.h"
24 #ifndef _WIN32
25 #include <sys/resource.h>
26 #endif
27 #ifdef CONFIG_DARWIN
28 #include <mach/mach_init.h>
29 #include <mach/thread_act.h>
30 #include <mach/mach_port.h>
31 #endif
32
33
34 static int qcrypto_pbkdf2_get_thread_cpu(unsigned long long *val_ms,
35 Error **errp)
36 {
37 #ifdef _WIN32
38 FILETIME creation_time, exit_time, kernel_time, user_time;
39 ULARGE_INTEGER thread_time;
40
41 if (!GetThreadTimes(GetCurrentThread(), &creation_time, &exit_time,
42 &kernel_time, &user_time)) {
43 error_setg(errp, "Unable to get thread CPU usage");
44 return -1;
45 }
46
47 thread_time.LowPart = user_time.dwLowDateTime;
48 thread_time.HighPart = user_time.dwHighDateTime;
49
50 /* QuadPart is units of 100ns and we want ms as unit */
51 *val_ms = thread_time.QuadPart / 10000ll;
52 return 0;
53 #elif defined(CONFIG_DARWIN)
54 mach_port_t thread;
55 kern_return_t kr;
56 mach_msg_type_number_t count;
57 thread_basic_info_data_t info;
58
59 thread = mach_thread_self();
60 count = THREAD_BASIC_INFO_COUNT;
61 kr = thread_info(thread, THREAD_BASIC_INFO, (thread_info_t)&info, &count);
62 mach_port_deallocate(mach_task_self(), thread);
63 if (kr != KERN_SUCCESS || (info.flags & TH_FLAGS_IDLE) != 0) {
64 error_setg_errno(errp, errno, "Unable to get thread CPU usage");
65 return -1;
66 }
67
68 *val_ms = ((info.user_time.seconds * 1000ll) +
69 (info.user_time.microseconds / 1000));
70 return 0;
71 #elif defined(RUSAGE_THREAD)
72 struct rusage ru;
73 if (getrusage(RUSAGE_THREAD, &ru) < 0) {
74 error_setg_errno(errp, errno, "Unable to get thread CPU usage");
75 return -1;
76 }
77
78 *val_ms = ((ru.ru_utime.tv_sec * 1000ll) +
79 (ru.ru_utime.tv_usec / 1000));
80 return 0;
81 #else
82 *val_ms = 0;
83 error_setg(errp, "Unable to calculate thread CPU usage on this platform");
84 return -1;
85 #endif
86 }
87
88 uint64_t qcrypto_pbkdf2_count_iters(QCryptoHashAlgorithm hash,
89 const uint8_t *key, size_t nkey,
90 const uint8_t *salt, size_t nsalt,
91 size_t nout,
92 Error **errp)
93 {
94 uint64_t ret = -1;
95 g_autofree uint8_t *out = g_new(uint8_t, nout);
96 uint64_t iterations = (1 << 15);
97 unsigned long long delta_ms, start_ms, end_ms;
98
99 while (1) {
100 if (qcrypto_pbkdf2_get_thread_cpu(&start_ms, errp) < 0) {
101 goto cleanup;
102 }
103 if (qcrypto_pbkdf2(hash,
104 key, nkey,
105 salt, nsalt,
106 iterations,
107 out, nout,
108 errp) < 0) {
109 goto cleanup;
110 }
111 if (qcrypto_pbkdf2_get_thread_cpu(&end_ms, errp) < 0) {
112 goto cleanup;
113 }
114
115 delta_ms = end_ms - start_ms;
116
117 if (delta_ms > 500) {
118 break;
119 } else if (delta_ms < 100) {
120 iterations = iterations * 10;
121 } else {
122 iterations = (iterations * 1000 / delta_ms);
123 }
124 }
125
126 iterations = iterations * 1000 / delta_ms;
127
128 ret = iterations;
129
130 cleanup:
131 memset(out, 0, nout);
132 return ret;
133 }