| 1 | //===-- Windows implementation of getentropy ------------------------------===// |
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| 2 | // |
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| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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| 4 | // See https://llvm.org/LICENSE.txt for license information. |
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| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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| 6 | // |
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| 7 | //===----------------------------------------------------------------------===// |
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| 8 | |
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| 9 | #include "src/unistd/getentropy.h" |
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| 10 | #include "hdr/errno_macros.h" |
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| 11 | #include "src/__support/common.h" |
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| 12 | #include "src/__support/libc_errno.h" |
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| 13 | |
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| 14 | #define WIN32_LEAN_AND_MEAN |
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| 15 | #include <Windows.h> |
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| 16 | #include <bcrypt.h> |
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| 17 | #include <ntstatus.h> |
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| 18 | #pragma comment(lib, "bcrypt.lib") |
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| 19 | |
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| 20 | namespace LIBC_NAMESPACE_DECL { |
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| 21 | |
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| 22 | LLVM_LIBC_FUNCTION(int, getentropy, (void *buffer, size_t length)) { |
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| 23 | __try { |
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| 24 | // check the length limit |
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| 25 | if (length > 256) |
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| 26 | __leave; |
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| 27 | |
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| 28 | NTSTATUS result = ::BCryptGenRandom(nullptr, static_cast<PUCHAR>(buffer), |
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| 29 | static_cast<ULONG>(length), |
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| 30 | BCRYPT_USE_SYSTEM_PREFERRED_RNG); |
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| 31 | |
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| 32 | if (result == STATUS_SUCCESS) |
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| 33 | return 0; |
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| 34 | |
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| 35 | } __except (EXCEPTION_EXECUTE_HANDLER) { |
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| 36 | // no need to handle exceptions specially |
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| 37 | } |
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| 38 | |
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| 39 | libc_errno = EIO; |
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| 40 | return -1; |
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| 41 | } |
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| 42 | } // namespace LIBC_NAMESPACE_DECL |
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| 43 | |
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