mirror of
https://github.com/xemu-project/xemu.git
synced 2024-11-23 03:29:43 +00:00
bf98afc75e
When the user creates a LUKS-encrypted qcow2 image using the qemu-img program, the passphrase is hashed using PBKDF2 with a dynamic number of iterations. The number of iterations is determined by measuring thread cpu time usage, such that it takes approximately 2 seconds to compute the hash. Because Darwin doesn't implement getrusage(RUSAGE_THREAD), we get an error message: > qemu-img: test.qcow2: Unable to calculate thread CPU usage on this platform for this command: > qemu-img create --object secret,id=key,data=1234 -f qcow2 -o 'encrypt.format=luks,encrypt.key-secret=key' test.qcow2 100M This patch implements qcrypto_pbkdf2_get_thread_cpu() for Darwin so that the above command works. Signed-off-by: Jungmin Park <pjm0616@gmail.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
134 lines
4.0 KiB
C
134 lines
4.0 KiB
C
/*
|
|
* QEMU Crypto PBKDF support (Password-Based Key Derivation Function)
|
|
*
|
|
* Copyright (c) 2015-2016 Red Hat, Inc.
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
*/
|
|
|
|
#include "qemu/osdep.h"
|
|
#include "qapi/error.h"
|
|
#include "crypto/pbkdf.h"
|
|
#ifndef _WIN32
|
|
#include <sys/resource.h>
|
|
#endif
|
|
#ifdef CONFIG_DARWIN
|
|
#include <mach/mach_init.h>
|
|
#include <mach/thread_act.h>
|
|
#include <mach/mach_port.h>
|
|
#endif
|
|
|
|
|
|
static int qcrypto_pbkdf2_get_thread_cpu(unsigned long long *val_ms,
|
|
Error **errp)
|
|
{
|
|
#ifdef _WIN32
|
|
FILETIME creation_time, exit_time, kernel_time, user_time;
|
|
ULARGE_INTEGER thread_time;
|
|
|
|
if (!GetThreadTimes(GetCurrentThread(), &creation_time, &exit_time,
|
|
&kernel_time, &user_time)) {
|
|
error_setg(errp, "Unable to get thread CPU usage");
|
|
return -1;
|
|
}
|
|
|
|
thread_time.LowPart = user_time.dwLowDateTime;
|
|
thread_time.HighPart = user_time.dwHighDateTime;
|
|
|
|
/* QuadPart is units of 100ns and we want ms as unit */
|
|
*val_ms = thread_time.QuadPart / 10000ll;
|
|
return 0;
|
|
#elif defined(CONFIG_DARWIN)
|
|
mach_port_t thread;
|
|
kern_return_t kr;
|
|
mach_msg_type_number_t count;
|
|
thread_basic_info_data_t info;
|
|
|
|
thread = mach_thread_self();
|
|
count = THREAD_BASIC_INFO_COUNT;
|
|
kr = thread_info(thread, THREAD_BASIC_INFO, (thread_info_t)&info, &count);
|
|
mach_port_deallocate(mach_task_self(), thread);
|
|
if (kr != KERN_SUCCESS || (info.flags & TH_FLAGS_IDLE) != 0) {
|
|
error_setg_errno(errp, errno, "Unable to get thread CPU usage");
|
|
return -1;
|
|
}
|
|
|
|
*val_ms = ((info.user_time.seconds * 1000ll) +
|
|
(info.user_time.microseconds / 1000));
|
|
return 0;
|
|
#elif defined(RUSAGE_THREAD)
|
|
struct rusage ru;
|
|
if (getrusage(RUSAGE_THREAD, &ru) < 0) {
|
|
error_setg_errno(errp, errno, "Unable to get thread CPU usage");
|
|
return -1;
|
|
}
|
|
|
|
*val_ms = ((ru.ru_utime.tv_sec * 1000ll) +
|
|
(ru.ru_utime.tv_usec / 1000));
|
|
return 0;
|
|
#else
|
|
*val_ms = 0;
|
|
error_setg(errp, "Unable to calculate thread CPU usage on this platform");
|
|
return -1;
|
|
#endif
|
|
}
|
|
|
|
uint64_t qcrypto_pbkdf2_count_iters(QCryptoHashAlgorithm hash,
|
|
const uint8_t *key, size_t nkey,
|
|
const uint8_t *salt, size_t nsalt,
|
|
size_t nout,
|
|
Error **errp)
|
|
{
|
|
uint64_t ret = -1;
|
|
g_autofree uint8_t *out = g_new(uint8_t, nout);
|
|
uint64_t iterations = (1 << 15);
|
|
unsigned long long delta_ms, start_ms, end_ms;
|
|
|
|
while (1) {
|
|
if (qcrypto_pbkdf2_get_thread_cpu(&start_ms, errp) < 0) {
|
|
goto cleanup;
|
|
}
|
|
if (qcrypto_pbkdf2(hash,
|
|
key, nkey,
|
|
salt, nsalt,
|
|
iterations,
|
|
out, nout,
|
|
errp) < 0) {
|
|
goto cleanup;
|
|
}
|
|
if (qcrypto_pbkdf2_get_thread_cpu(&end_ms, errp) < 0) {
|
|
goto cleanup;
|
|
}
|
|
|
|
delta_ms = end_ms - start_ms;
|
|
|
|
if (delta_ms > 500) {
|
|
break;
|
|
} else if (delta_ms < 100) {
|
|
iterations = iterations * 10;
|
|
} else {
|
|
iterations = (iterations * 1000 / delta_ms);
|
|
}
|
|
}
|
|
|
|
iterations = iterations * 1000 / delta_ms;
|
|
|
|
ret = iterations;
|
|
|
|
cleanup:
|
|
memset(out, 0, nout);
|
|
return ret;
|
|
}
|