Refactor low-level crypto to C++ style. #1028

Job	Run time
Windows-2022 [arch x64, toolset v143, backend botan, build shared libs off, use CMake prefix path on, sanitizers off]	17m 4s
Windows-2022 [arch x64, toolset v143, backend botan, build shared libs off, use CMake prefix path off, sanitizers off]	17m 51s
Windows-2022 [arch x64, toolset v143, backend openssl, build shared libs off, use CMake prefix path on, sanitizers off]	14m 12s
Windows-2022 [arch x64, toolset v143, backend openssl, build shared libs off, use CMake prefix path off, sanitizers off]	17m 20s
Windows-2022 [arch x64, toolset ClangCL, backend botan, build shared libs off, use CMake prefix path on, sanitizers off]	20m 22s
Windows-2022 [arch x64, toolset ClangCL, backend botan, build shared libs off, use CMake prefix path off, sanitizers off]	22m 42s
Windows-2022 [arch x64, toolset ClangCL, backend openssl, build shared libs off, use CMake prefix path on, sanitizers off]	18m 18s
Windows-2022 [arch x64, toolset ClangCL, backend openssl, build shared libs off, use CMake prefix path off, sanitizers off]	19m 34s
Windows-2022 [arch x64, toolset v143, backend botan, build shared libs off, use CMake prefix path off, sanitizers on]	26m 38s
Windows-2022 [arch Win32, toolset ClangCL, backend botan, build shared libs off, use CMake prefix path on, sanitizers off]	25m 46s
Windows-2022 [arch Win32, toolset v143, backend openssl, build shared libs off, use CMake prefix path off, sanitizers off]	18m 58s
	3h 38m 45s

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