libcryfs/src/cryfs-cli/Cli.cpp

385 lines
15 KiB
C++

#include "Cli.h"
#include <blockstore/implementations/ondisk/OnDiskBlockStore.h>
#include <blockstore/implementations/inmemory/InMemoryBlockStore.h>
#include <blockstore/implementations/inmemory/InMemoryBlock.h>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cpp-utils/assert/backtrace.h>
#include <fspp/fuse/Fuse.h>
#include <fspp/impl/FilesystemImpl.h>
#include <cpp-utils/process/subprocess.h>
#include <cpp-utils/io/DontEchoStdinToStdoutRAII.h>
#include <cryfs/filesystem/CryDevice.h>
#include <cryfs/config/CryConfigLoader.h>
#include "program_options/Parser.h"
#include <boost/filesystem.hpp>
#include <cryfs/filesystem/CryDir.h>
#include <gitversion/gitversion.h>
#include "VersionChecker.h"
#include <gitversion/VersionCompare.h>
#include <cpp-utils/io/NoninteractiveConsole.h>
#include "Environment.h"
#include <cryfs/CryfsException.h>
//TODO Many functions accessing the ProgramOptions object. Factor out into class that stores it as a member.
//TODO Factor out class handling askPassword
using namespace cryfs;
namespace bf = boost::filesystem;
using namespace cpputils::logging;
using blockstore::ondisk::OnDiskBlockStore;
using blockstore::inmemory::InMemoryBlockStore;
using program_options::ProgramOptions;
using cpputils::make_unique_ref;
using cpputils::Random;
using cpputils::NoninteractiveConsole;
using cpputils::TempFile;
using cpputils::RandomGenerator;
using cpputils::unique_ref;
using cpputils::SCryptSettings;
using cpputils::Console;
using cpputils::HttpClient;
using cpputils::DontEchoStdinToStdoutRAII;
using std::cin;
using std::cout;
using std::string;
using std::endl;
using std::vector;
using std::shared_ptr;
using std::make_shared;
using std::unique_ptr;
using std::make_unique;
using std::function;
using std::make_shared;
using boost::optional;
using boost::none;
using boost::chrono::duration;
using boost::chrono::duration_cast;
using boost::chrono::minutes;
using boost::chrono::milliseconds;
using cpputils::dynamic_pointer_move;
using gitversion::VersionCompare;
//TODO Delete a large file in parallel possible? Takes a long time right now...
//TODO Improve parallelity.
//TODO Replace ASSERTs with other error handling when it is not a programming error but an environment influence (e.g. a block is missing)
//TODO Can we improve performance by setting compiler parameter -maes for scrypt?
namespace cryfs {
Cli::Cli(RandomGenerator &keyGenerator, const SCryptSettings &scryptSettings, shared_ptr<Console> console, shared_ptr<HttpClient> httpClient):
_keyGenerator(keyGenerator), _scryptSettings(scryptSettings), _console(), _httpClient(httpClient), _noninteractive(false) {
_noninteractive = Environment::isNoninteractive();
if (_noninteractive) {
_console = make_shared<NoninteractiveConsole>(console);
} else {
_console = console;
}
}
void Cli::_showVersion() {
cout << "CryFS Version " << gitversion::VersionString() << endl;
if (gitversion::IsDevVersion()) {
cout << "WARNING! This is a development version based on git commit " << gitversion::GitCommitId() <<
". Please do not use in production!" << endl;
} else if (!gitversion::IsStableVersion()) {
cout << "WARNING! This is an experimental version. Please backup your data frequently!" << endl;
}
#ifndef NDEBUG
cout << "WARNING! This is a debug build. Performance might be slow." << endl;
#endif
#ifndef CRYFS_NO_UPDATE_CHECKS
if (Environment::noUpdateCheck()) {
cout << "Automatic checking for security vulnerabilities and updates is disabled." << endl;
} else if (Environment::isNoninteractive()) {
cout << "Automatic checking for security vulnerabilities and updates is disabled in noninteractive mode." << endl;
} else {
_checkForUpdates();
}
#else
# warning Update checks are disabled. The resulting executable will not go online to check for newer versions or known security vulnerabilities.
#endif
cout << endl;
}
void Cli::_checkForUpdates() {
VersionChecker versionChecker(_httpClient);
optional<string> newestVersion = versionChecker.newestVersion();
if (newestVersion == none) {
cout << "Could not check for updates." << endl;
} else if (VersionCompare::isOlderThan(gitversion::VersionString(), *newestVersion)) {
cout << "CryFS " << *newestVersion << " is released. Please update." << endl;
}
optional<string> securityWarning = versionChecker.securityWarningFor(gitversion::VersionString());
if (securityWarning != none) {
cout << *securityWarning << endl;
}
}
bool Cli::_checkPassword(const string &password) {
if (password == "") {
std::cerr << "Empty password not allowed. Please try again." << std::endl;
return false;
}
return true;
}
string Cli::_askPasswordForExistingFilesystem() {
string password = _askPasswordFromStdin("Password: ");
while (!_checkPassword(password)) {
password = _askPasswordFromStdin("Password: ");
}
return password;
};
string Cli::_askPasswordForNewFilesystem() {
string password;
bool again = false;
do {
password = _askPasswordFromStdin("Password: ");
if (!_checkPassword(password)) {
again = true;
continue;
}
if (!_confirmPassword(password)) {
again = true;
continue;
}
again = false;
} while(again);
return password;
}
bool Cli::_confirmPassword(const string &password) {
string confirmPassword = _askPasswordFromStdin("Confirm Password: ");
if (password != confirmPassword) {
std::cout << "Passwords don't match" << std::endl;
return false;
}
return true;
}
string Cli::_askPasswordNoninteractive() {
//TODO Test
string password = _askPasswordFromStdin("Password: ");
if (!_checkPassword(password)) {
throw CryfsException("Invalid password. Password cannot be empty.", ErrorCode::EmptyPassword);
}
return password;
}
string Cli::_askPasswordFromStdin(const string &prompt) {
DontEchoStdinToStdoutRAII _stdin_input_is_hidden_as_long_as_this_is_in_scope;
std::cout << prompt << std::flush;
string result;
std::getline(cin, result);
std::cout << std::endl;
//Remove trailing newline
if (result[result.size()-1] == '\n') {
result.resize(result.size()-1);
}
return result;
}
bf::path Cli::_determineConfigFile(const ProgramOptions &options) {
auto configFile = options.configFile();
if (configFile == none) {
return bf::path(options.baseDir()) / "cryfs.config";
}
return *configFile;
}
CryConfigFile Cli::_loadOrCreateConfig(const ProgramOptions &options) {
auto configFile = _determineConfigFile(options);
auto config = _loadOrCreateConfigFile(configFile, options.cipher(), options.blocksizeBytes(),
options.allowFilesystemUpgrade());
if (config == none) {
throw CryfsException("Could not load config file. Did you enter the correct password?", ErrorCode::WrongPassword);
}
return std::move(*config);
}
optional<CryConfigFile> Cli::_loadOrCreateConfigFile(const bf::path &configFilePath, const optional<string> &cipher, const optional<uint32_t> &blocksizeBytes, bool allowFilesystemUpgrade) {
if (_noninteractive) {
return CryConfigLoader(_console, _keyGenerator, _scryptSettings,
&Cli::_askPasswordNoninteractive,
&Cli::_askPasswordNoninteractive,
cipher, blocksizeBytes).loadOrCreate(configFilePath, allowFilesystemUpgrade);
} else {
return CryConfigLoader(_console, _keyGenerator, _scryptSettings,
&Cli::_askPasswordForExistingFilesystem,
&Cli::_askPasswordForNewFilesystem,
cipher, blocksizeBytes).loadOrCreate(configFilePath, allowFilesystemUpgrade);
}
}
void Cli::_runFilesystem(const ProgramOptions &options) {
try {
auto blockStore = make_unique_ref<OnDiskBlockStore>(options.baseDir());
auto config = _loadOrCreateConfig(options);
CryDevice device(std::move(config), std::move(blockStore));
_sanityCheckFilesystem(&device);
fspp::FilesystemImpl fsimpl(&device);
fspp::fuse::Fuse fuse(&fsimpl, "cryfs", "cryfs@"+options.baseDir().native());
_initLogfile(options);
//TODO Test auto unmounting after idle timeout
//TODO This can fail due to a race condition if the filesystem isn't started yet (e.g. passing --unmount-idle 0").
auto idleUnmounter = _createIdleCallback(options.unmountAfterIdleMinutes(), [&fuse] {fuse.stop();});
if (idleUnmounter != none) {
device.onFsAction(std::bind(&CallAfterTimeout::resetTimer, idleUnmounter->get()));
}
#ifdef __APPLE__
std::cout << "\nMounting filesystem. To unmount, call:\n$ umount " << options.mountDir() << "\n" << std::endl;
#else
std::cout << "\nMounting filesystem. To unmount, call:\n$ fusermount -u " << options.mountDir() << "\n" << std::endl;
#endif
fuse.run(options.mountDir(), options.fuseOptions());
} catch (const std::exception &e) {
LOG(ERROR, "Crashed: {}", e.what());
} catch (...) {
LOG(ERROR, "Crashed");
}
}
void Cli::_sanityCheckFilesystem(CryDevice *device) {
//Try to list contents of base directory
auto _rootDir = device->Load("/"); // this might throw an exception if the root blob doesn't exist
if (_rootDir == none) {
throw CryfsException("Couldn't find root blob", ErrorCode::InvalidFilesystem);
}
auto rootDir = dynamic_pointer_move<CryDir>(*_rootDir);
if (rootDir == none) {
throw CryfsException("Base directory blob doesn't contain a directory", ErrorCode::InvalidFilesystem);
}
(*rootDir)->children(); // Load children
}
optional<unique_ref<CallAfterTimeout>> Cli::_createIdleCallback(optional<double> minutes, function<void()> callback) {
if (minutes == none) {
return none;
}
uint64_t millis = std::round(60000 * (*minutes));
return make_unique_ref<CallAfterTimeout>(milliseconds(millis), callback);
}
void Cli::_initLogfile(const ProgramOptions &options) {
spdlog::drop("cryfs");
//TODO Test that --logfile parameter works. Should be: file if specified, otherwise stderr if foreground, else syslog.
if (options.logFile() != none) {
cpputils::logging::setLogger(
spdlog::create<spdlog::sinks::simple_file_sink<std::mutex>>("cryfs", options.logFile()->native()));
} else if (options.foreground()) {
cpputils::logging::setLogger(spdlog::stderr_logger_mt("cryfs"));
} else {
cpputils::logging::setLogger(spdlog::syslog_logger("cryfs", "cryfs", LOG_PID));
}
}
void Cli::_sanityChecks(const ProgramOptions &options) {
_checkDirAccessible(options.baseDir(), "base directory", ErrorCode::InaccessibleBaseDir);
_checkDirAccessible(options.mountDir(), "mount directory", ErrorCode::InaccessibleMountDir);
_checkMountdirDoesntContainBasedir(options);
}
void Cli::_checkDirAccessible(const bf::path &dir, const std::string &name, ErrorCode errorCode) {
if (!bf::exists(dir)) {
bool create = _console->askYesNo("Could not find " + name + ". Do you want to create it?", false);
if (create) {
if (!bf::create_directory(dir)) {
throw CryfsException("Error creating "+name, errorCode);
}
} else {
//std::cerr << "Exit code: " << exitCode(errorCode) << std::endl;
throw CryfsException(name + " not found.", errorCode);
}
}
if (!bf::is_directory(dir)) {
throw CryfsException(name+" is not a directory.", errorCode);
}
auto file = _checkDirWriteable(dir, name, errorCode);
_checkDirReadable(dir, file, name, errorCode);
}
shared_ptr<TempFile> Cli::_checkDirWriteable(const bf::path &dir, const std::string &name, ErrorCode errorCode) {
auto path = dir / "tempfile";
try {
return make_shared<TempFile>(path);
} catch (const std::runtime_error &e) {
throw CryfsException("Could not write to "+name+".", errorCode);
}
}
void Cli::_checkDirReadable(const bf::path &dir, shared_ptr<TempFile> tempfile, const std::string &name, ErrorCode errorCode) {
ASSERT(bf::equivalent(dir, tempfile->path().parent_path()), "This function should be called with a file inside the directory");
try {
bool found = false;
bf::directory_iterator end;
for (auto iter = bf::directory_iterator(dir); iter != end; ++iter) {
if (bf::equivalent(*iter, tempfile->path())) {
found = true;
}
}
if (!found) {
//This should not happen. Can only happen if the written temp file got deleted inbetween or maybe was not written at all.
throw std::runtime_error("Error accessing "+name+".");
}
} catch (const boost::filesystem::filesystem_error &e) {
throw CryfsException("Could not read from "+name+".", errorCode);
}
}
void Cli::_checkMountdirDoesntContainBasedir(const ProgramOptions &options) {
if (_pathContains(options.mountDir(), options.baseDir())) {
throw CryfsException("base directory can't be inside the mount directory.", ErrorCode::BaseDirInsideMountDir);
}
}
bool Cli::_pathContains(const bf::path &parent, const bf::path &child) {
bf::path absParent = bf::canonical(parent);
bf::path current = bf::canonical(child);
if (absParent.empty() && current.empty()) {
return true;
}
while(!current.empty()) {
if (bf::equivalent(current, absParent)) {
return true;
}
current = current.parent_path();
}
return false;
}
int Cli::main(int argc, const char *argv[]) {
cpputils::showBacktraceOnSigSegv();
try {
_showVersion();
ProgramOptions options = program_options::Parser(argc, argv).parse(CryCiphers::supportedCipherNames());
_sanityChecks(options);
_runFilesystem(options);
} catch (const CryfsException &e) {
if (e.errorCode() != ErrorCode::Success) {
std::cerr << "Error: " << e.what() << std::endl;
}
return exitCode(e.errorCode());
} catch (const std::runtime_error &e) {
std::cerr << "Error: " << e.what() << std::endl;
return exitCode(ErrorCode::UnspecifiedError);
}
return exitCode(ErrorCode::Success);
}
}