nix-super/src/libstore/legacy-ssh-store.cc
John Ericson 470c0501eb Ensure all store types support "real" URIs
In particular `local://<path>` and `unix://` (without any path) now
work, and mean the same things as `local` and `daemon`, respectively. We
thus now have the opportunity to desguar `local` and `daemon` early.

This will allow me to make a change to
https://github.com/NixOS/nix/pull/9839 requested during review to
desugar those earlier.

Co-authored-by: Théophane Hufschmitt <7226587+thufschmitt@users.noreply.github.com>
2024-05-21 11:56:40 -04:00

328 lines
8.9 KiB
C++

#include "legacy-ssh-store.hh"
#include "ssh-store-config.hh"
#include "archive.hh"
#include "pool.hh"
#include "remote-store.hh"
#include "serve-protocol.hh"
#include "serve-protocol-impl.hh"
#include "build-result.hh"
#include "store-api.hh"
#include "path-with-outputs.hh"
#include "ssh.hh"
#include "derivations.hh"
#include "callback.hh"
namespace nix {
std::string LegacySSHStoreConfig::doc()
{
return
#include "legacy-ssh-store.md"
;
}
struct LegacySSHStore::Connection : public ServeProto::BasicClientConnection
{
std::unique_ptr<SSHMaster::Connection> sshConn;
bool good = true;
};
LegacySSHStore::LegacySSHStore(
std::string_view scheme,
std::string_view host,
const Params & params)
: LegacySSHStore{scheme, LegacySSHStoreConfig::extractConnStr(scheme, host), params}
{
}
LegacySSHStore::LegacySSHStore(
std::string_view scheme,
std::string host,
const Params & params)
: StoreConfig(params)
, CommonSSHStoreConfig(params)
, LegacySSHStoreConfig(params)
, Store(params)
, host(host)
, connections(make_ref<Pool<Connection>>(
std::max(1, (int) maxConnections),
[this]() { return openConnection(); },
[](const ref<Connection> & r) { return r->good; }
))
, master(
host,
sshKey.get(),
sshPublicHostKey.get(),
// Use SSH master only if using more than 1 connection.
connections->capacity() > 1,
compress,
logFD)
{
}
ref<LegacySSHStore::Connection> LegacySSHStore::openConnection()
{
auto conn = make_ref<Connection>();
Strings command = remoteProgram.get();
command.push_back("--serve");
command.push_back("--write");
if (remoteStore.get() != "") {
command.push_back("--store");
command.push_back(remoteStore.get());
}
conn->sshConn = master.startCommand(std::move(command));
conn->to = FdSink(conn->sshConn->in.get());
conn->from = FdSource(conn->sshConn->out.get());
StringSink saved;
TeeSource tee(conn->from, saved);
try {
conn->remoteVersion = ServeProto::BasicClientConnection::handshake(
conn->to, tee, SERVE_PROTOCOL_VERSION, host);
} catch (SerialisationError & e) {
// in.close(): Don't let the remote block on us not writing.
conn->sshConn->in.close();
{
NullSink nullSink;
conn->from.drainInto(nullSink);
}
throw Error("'nix-store --serve' protocol mismatch from '%s', got '%s'",
host, chomp(saved.s));
} catch (EndOfFile & e) {
throw Error("cannot connect to '%1%'", host);
}
return conn;
};
std::string LegacySSHStore::getUri()
{
return *uriSchemes().begin() + "://" + host;
}
void LegacySSHStore::queryPathInfoUncached(const StorePath & path,
Callback<std::shared_ptr<const ValidPathInfo>> callback) noexcept
{
try {
auto conn(connections->get());
/* No longer support missing NAR hash */
assert(GET_PROTOCOL_MINOR(conn->remoteVersion) >= 4);
debug("querying remote host '%s' for info on '%s'", host, printStorePath(path));
auto infos = conn->queryPathInfos(*this, {path});
switch (infos.size()) {
case 0:
return callback(nullptr);
case 1: {
auto & [path2, info] = *infos.begin();
if (info.narHash == Hash::dummy)
throw Error("NAR hash is now mandatory");
assert(path == path2);
return callback(std::make_shared<ValidPathInfo>(
std::move(path),
std::move(info)
));
}
default:
throw Error("More path infos returned than queried");
}
} catch (...) { callback.rethrow(); }
}
void LegacySSHStore::addToStore(const ValidPathInfo & info, Source & source,
RepairFlag repair, CheckSigsFlag checkSigs)
{
debug("adding path '%s' to remote host '%s'", printStorePath(info.path), host);
auto conn(connections->get());
if (GET_PROTOCOL_MINOR(conn->remoteVersion) >= 5) {
conn->to
<< ServeProto::Command::AddToStoreNar
<< printStorePath(info.path)
<< (info.deriver ? printStorePath(*info.deriver) : "")
<< info.narHash.to_string(HashFormat::Base16, false);
ServeProto::write(*this, *conn, info.references);
conn->to
<< info.registrationTime
<< info.narSize
<< info.ultimate
<< info.sigs
<< renderContentAddress(info.ca);
try {
copyNAR(source, conn->to);
} catch (...) {
conn->good = false;
throw;
}
conn->to.flush();
} else {
conn->to
<< ServeProto::Command::ImportPaths
<< 1;
try {
copyNAR(source, conn->to);
} catch (...) {
conn->good = false;
throw;
}
conn->to
<< exportMagic
<< printStorePath(info.path);
ServeProto::write(*this, *conn, info.references);
conn->to
<< (info.deriver ? printStorePath(*info.deriver) : "")
<< 0
<< 0;
conn->to.flush();
}
if (readInt(conn->from) != 1)
throw Error("failed to add path '%s' to remote host '%s'", printStorePath(info.path), host);
}
void LegacySSHStore::narFromPath(const StorePath & path, Sink & sink)
{
auto conn(connections->get());
conn->to << ServeProto::Command::DumpStorePath << printStorePath(path);
conn->to.flush();
copyNAR(conn->from, sink);
}
static ServeProto::BuildOptions buildSettings()
{
return {
.maxSilentTime = settings.maxSilentTime,
.buildTimeout = settings.buildTimeout,
.maxLogSize = settings.maxLogSize,
.nrRepeats = 0, // buildRepeat hasn't worked for ages anyway
.enforceDeterminism = 0,
.keepFailed = settings.keepFailed,
};
}
BuildResult LegacySSHStore::buildDerivation(const StorePath & drvPath, const BasicDerivation & drv,
BuildMode buildMode)
{
auto conn(connections->get());
conn->putBuildDerivationRequest(*this, drvPath, drv, buildSettings());
return ServeProto::Serialise<BuildResult>::read(*this, *conn);
}
void LegacySSHStore::buildPaths(const std::vector<DerivedPath> & drvPaths, BuildMode buildMode, std::shared_ptr<Store> evalStore)
{
if (evalStore && evalStore.get() != this)
throw Error("building on an SSH store is incompatible with '--eval-store'");
auto conn(connections->get());
conn->to << ServeProto::Command::BuildPaths;
Strings ss;
for (auto & p : drvPaths) {
auto sOrDrvPath = StorePathWithOutputs::tryFromDerivedPath(p);
std::visit(overloaded {
[&](const StorePathWithOutputs & s) {
ss.push_back(s.to_string(*this));
},
[&](const StorePath & drvPath) {
throw Error("wanted to fetch '%s' but the legacy ssh protocol doesn't support merely substituting drv files via the build paths command. It would build them instead. Try using ssh-ng://", printStorePath(drvPath));
},
[&](std::monostate) {
throw Error("wanted build derivation that is itself a build product, but the legacy ssh protocol doesn't support that. Try using ssh-ng://");
},
}, sOrDrvPath);
}
conn->to << ss;
ServeProto::write(*this, *conn, buildSettings());
conn->to.flush();
BuildResult result;
result.status = (BuildResult::Status) readInt(conn->from);
if (!result.success()) {
conn->from >> result.errorMsg;
throw Error(result.status, result.errorMsg);
}
}
void LegacySSHStore::computeFSClosure(const StorePathSet & paths,
StorePathSet & out, bool flipDirection,
bool includeOutputs, bool includeDerivers)
{
if (flipDirection || includeDerivers) {
Store::computeFSClosure(paths, out, flipDirection, includeOutputs, includeDerivers);
return;
}
auto conn(connections->get());
conn->to
<< ServeProto::Command::QueryClosure
<< includeOutputs;
ServeProto::write(*this, *conn, paths);
conn->to.flush();
for (auto & i : ServeProto::Serialise<StorePathSet>::read(*this, *conn))
out.insert(i);
}
StorePathSet LegacySSHStore::queryValidPaths(const StorePathSet & paths,
SubstituteFlag maybeSubstitute)
{
auto conn(connections->get());
return conn->queryValidPaths(*this,
false, paths, maybeSubstitute);
}
void LegacySSHStore::connect()
{
auto conn(connections->get());
}
unsigned int LegacySSHStore::getProtocol()
{
auto conn(connections->get());
return conn->remoteVersion;
}
/**
* The legacy ssh protocol doesn't support checking for trusted-user.
* Try using ssh-ng:// instead if you want to know.
*/
std::optional<TrustedFlag> isTrustedClient()
{
return std::nullopt;
}
static RegisterStoreImplementation<LegacySSHStore, LegacySSHStoreConfig> regLegacySSHStore;
}