Files
U2FDevice/IO.cpp

113 lines
2.6 KiB
C++

/*
U2FDevice - A program to allow Raspberry Pi Zeros to act as U2F tokens
Copyright (C) 2018 Michael Kuc
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include "IO.hpp"
#include "Streams.hpp"
#include <iostream>
#include <unistd.h>
#include <stropts.h>
//#include <sys/ioctl.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "u2f.hpp"
#include "Macro.hpp"
using namespace std;
bool bytesAvailable(const size_t count);
vector<uint8_t>& getBuffer();
vector<uint8_t> readNonBlock(const size_t count)
{
if (!bytesAvailable(count))
{
//clog << "No bytes available" << endl;
return vector<uint8_t>{};
}
auto &buffer = getBuffer();
auto buffStart = buffer.begin(), buffEnd = buffer.begin() + count;
vector<uint8_t> bytes{ buffStart, buffEnd };
buffer.erase(buffStart, buffEnd);
fwrite(bytes.data(), 1, bytes.size(), getComHostStream().get());
errno = 0;
return bytes;
}
void write(const uint8_t* bytes, const size_t count)
{
size_t totalBytes = 0;
auto hostDescriptor = *getHostDescriptor();
while (totalBytes < count)
{
auto writtenBytes = write(hostDescriptor, bytes + totalBytes, count - totalBytes);
if (writtenBytes > 0)
totalBytes += writtenBytes;
else if (errno != 0 && errno != EAGAIN && errno != EWOULDBLOCK) //Expect file blocking behaviour
ERR();
}
errno = 0;
}
bool bytesAvailable(const size_t count)
{
return getBuffer().size() >= count;
}
vector<uint8_t>& bufferVar()
{
static vector<uint8_t> buffer{};
return buffer;
}
vector<uint8_t>& getBuffer()
{
auto &buff = bufferVar();
array<uint8_t, HID_RPT_SIZE> bytes{};
auto hostDescriptor = *getHostDescriptor();
while (true)
{
auto readByteCount = read(hostDescriptor, bytes.data(), HID_RPT_SIZE);
if (readByteCount > 0)
{
copy(bytes.begin(), bytes.begin() + readByteCount, back_inserter(buff));
}
else if (errno != EAGAIN && errno != EWOULDBLOCK) //Expect read would block
{
ERR();
}
else
{
break; //Escape loop if blocking would occur
}
}
return buff;
}