lix/src/libstore/ssh-store.cc
Eelco Dolstra 577ebeaefb
Improve SSH handling
* Unify SSH code in SSHStore and LegacySSHStore.

* Fix a race starting the SSH master. We now wait synchronously for
  the SSH master to finish starting. This prevents the SSH clients
  from starting their own connections.

* Don't use a master if max-connections == 1.

* Add a "max-connections" store parameter.

* Add a "compress" store parameter.
2017-03-03 19:05:50 +01:00

102 lines
2.4 KiB
C++

#include "store-api.hh"
#include "remote-store.hh"
#include "remote-fs-accessor.hh"
#include "archive.hh"
#include "worker-protocol.hh"
#include "pool.hh"
#include "ssh.hh"
namespace nix {
static std::string uriScheme = "ssh://";
class SSHStore : public RemoteStore
{
public:
SSHStore(const std::string & host, const Params & params)
: Store(params)
, RemoteStore(params)
, host(host)
, master(
host,
get(params, "ssh-key", ""),
// Use SSH master only if using more than 1 connection.
connections->capacity() > 1,
get(params, "compress", "") == "true")
{
}
std::string getUri() override
{
return uriScheme + host;
}
void narFromPath(const Path & path, Sink & sink) override;
ref<FSAccessor> getFSAccessor() override;
private:
struct Connection : RemoteStore::Connection
{
std::unique_ptr<SSHMaster::Connection> sshConn;
};
ref<RemoteStore::Connection> openConnection() override;
std::string host;
SSHMaster master;
};
class ForwardSource : public Source
{
Source & readSource;
Sink & writeSink;
public:
ForwardSource(Source & readSource, Sink & writeSink) : readSource(readSource), writeSink(writeSink) {}
size_t read(unsigned char * data, size_t len) override
{
auto res = readSource.read(data, len);
writeSink(data, len);
return res;
}
};
void SSHStore::narFromPath(const Path & path, Sink & sink)
{
auto conn(connections->get());
conn->to << wopNarFromPath << path;
conn->processStderr();
ParseSink ps;
auto fwd = ForwardSource(conn->from, sink);
parseDump(ps, fwd);
}
ref<FSAccessor> SSHStore::getFSAccessor()
{
return make_ref<RemoteFSAccessor>(ref<Store>(shared_from_this()));
}
ref<RemoteStore::Connection> SSHStore::openConnection()
{
auto conn = make_ref<Connection>();
conn->sshConn = master.startCommand("nix-daemon --stdio");
conn->to = FdSink(conn->sshConn->in.get());
conn->from = FdSource(conn->sshConn->out.get());
initConnection(*conn);
return conn;
}
static RegisterStoreImplementation regStore([](
const std::string & uri, const Store::Params & params)
-> std::shared_ptr<Store>
{
if (std::string(uri, 0, uriScheme.size()) != uriScheme) return 0;
return std::make_shared<SSHStore>(std::string(uri, uriScheme.size()), params);
});
}