close
Skip to content

Fix a race condition in unique_path. #15

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
Beman merged 1 commit into from
Aug 28, 2015
Merged

Fix a race condition in unique_path. #15

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
42 changes: 28 additions & 14 deletions src/unique_path.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -41,6 +41,33 @@ void fail(int err, boost::system::error_code* ec)
return;
}

#ifdef BOOST_WINDOWS_API

int acquire_crypt_handle(HCRYPTPROV& handle)
{
if (::CryptAcquireContextW(&handle, 0, 0, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT | CRYPT_SILENT))
return 0;

int errval = ::GetLastError();
if (errval != NTE_BAD_KEYSET)
return errval;

if (::CryptAcquireContextW(&handle, 0, 0, PROV_RSA_FULL, CRYPT_NEWKEYSET | CRYPT_VERIFYCONTEXT | CRYPT_SILENT))
return 0;

errval = ::GetLastError();
// Another thread could have attempted to create the keyset at the same time.
if (errval != NTE_EXISTS)
return errval;

if (::CryptAcquireContextW(&handle, 0, 0, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT | CRYPT_SILENT))
return 0;

return ::GetLastError();
}

#endif

void system_crypt_random(void* buf, std::size_t len, boost::system::error_code* ec)
{
# ifdef BOOST_POSIX_API
Expand Down Expand Up @@ -75,20 +102,7 @@ void system_crypt_random(void* buf, std::size_t len, boost::system::error_code*
# else // BOOST_WINDOWS_API

HCRYPTPROV handle;
int errval = 0;

if (!::CryptAcquireContextW(&handle, 0, 0, PROV_RSA_FULL, 0))
{
errval = ::GetLastError();
if (errval == NTE_BAD_KEYSET)
{
if (!::CryptAcquireContextW(&handle, 0, 0, PROV_RSA_FULL, CRYPT_NEWKEYSET))
{
errval = ::GetLastError();
}
else errval = 0;
}
}
int errval = acquire_crypt_handle(handle);

if (!errval)
{
Expand Down