| /* |
| * 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 |
| |
| |
| 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(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; |
| uint8_t *out; |
| uint64_t iterations = (1 << 15); |
| unsigned long long delta_ms, start_ms, end_ms; |
| |
| out = g_new(uint8_t, nout); |
| |
| 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); |
| g_free(out); |
| return ret; |
| } |