lix/src/libstore/legacy-ssh-store.cc
Eelco Dolstra eb6db4fd38 buildPaths(): Add an evalStore argument
With this, we don't have to copy the entire .drv closure to the
destination store ahead of time (or at all). Instead, buildPaths()
reads .drv files from the eval store and copies inputSrcs to the
destination store if it needs to build a derivation.

Issue #5025.
2021-07-22 09:59:51 +02:00

363 lines
12 KiB
C++

#include "archive.hh"
#include "pool.hh"
#include "remote-store.hh"
#include "serve-protocol.hh"
#include "store-api.hh"
#include "path-with-outputs.hh"
#include "worker-protocol.hh"
#include "ssh.hh"
#include "derivations.hh"
#include "callback.hh"
namespace nix {
struct LegacySSHStoreConfig : virtual StoreConfig
{
using StoreConfig::StoreConfig;
const Setting<int> maxConnections{(StoreConfig*) this, 1, "max-connections", "maximum number of concurrent SSH connections"};
const Setting<Path> sshKey{(StoreConfig*) this, "", "ssh-key", "path to an SSH private key"};
const Setting<std::string> sshPublicHostKey{(StoreConfig*) this, "", "base64-ssh-public-host-key", "The public half of the host's SSH key"};
const Setting<bool> compress{(StoreConfig*) this, false, "compress", "whether to compress the connection"};
const Setting<Path> remoteProgram{(StoreConfig*) this, "nix-store", "remote-program", "path to the nix-store executable on the remote system"};
const Setting<std::string> remoteStore{(StoreConfig*) this, "", "remote-store", "URI of the store on the remote system"};
const std::string name() override { return "Legacy SSH Store"; }
};
struct LegacySSHStore : public virtual LegacySSHStoreConfig, public virtual Store
{
// Hack for getting remote build log output.
// Intentionally not in `LegacySSHStoreConfig` so that it doesn't appear in
// the documentation
const Setting<int> logFD{(StoreConfig*) this, -1, "log-fd", "file descriptor to which SSH's stderr is connected"};
struct Connection
{
std::unique_ptr<SSHMaster::Connection> sshConn;
FdSink to;
FdSource from;
int remoteVersion;
bool good = true;
};
std::string host;
ref<Pool<Connection>> connections;
SSHMaster master;
static std::set<std::string> uriSchemes() { return {"ssh"}; }
LegacySSHStore(const string & scheme, const string & host, const Params & params)
: StoreConfig(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,
sshPublicHostKey,
// Use SSH master only if using more than 1 connection.
connections->capacity() > 1,
compress,
logFD)
{
}
ref<Connection> openConnection()
{
auto conn = make_ref<Connection>();
conn->sshConn = master.startCommand(
fmt("%s --serve --write", remoteProgram)
+ (remoteStore.get() == "" ? "" : " --store " + shellEscape(remoteStore.get())));
conn->to = FdSink(conn->sshConn->in.get());
conn->from = FdSource(conn->sshConn->out.get());
try {
conn->to << SERVE_MAGIC_1 << SERVE_PROTOCOL_VERSION;
conn->to.flush();
unsigned int magic = readInt(conn->from);
if (magic != SERVE_MAGIC_2)
throw Error("protocol mismatch with 'nix-store --serve' on '%s'", host);
conn->remoteVersion = readInt(conn->from);
if (GET_PROTOCOL_MAJOR(conn->remoteVersion) != 0x200)
throw Error("unsupported 'nix-store --serve' protocol version on '%s'", host);
} catch (EndOfFile & e) {
throw Error("cannot connect to '%1%'", host);
}
return conn;
};
string getUri() override
{
return *uriSchemes().begin() + "://" + host;
}
void queryPathInfoUncached(const StorePath & path,
Callback<std::shared_ptr<const ValidPathInfo>> callback) noexcept override
{
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));
conn->to << cmdQueryPathInfos << PathSet{printStorePath(path)};
conn->to.flush();
auto p = readString(conn->from);
if (p.empty()) return callback(nullptr);
auto path2 = parseStorePath(p);
assert(path == path2);
/* Hash will be set below. FIXME construct ValidPathInfo at end. */
auto info = std::make_shared<ValidPathInfo>(path, Hash::dummy);
PathSet references;
auto deriver = readString(conn->from);
if (deriver != "")
info->deriver = parseStorePath(deriver);
info->references = worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
readLongLong(conn->from); // download size
info->narSize = readLongLong(conn->from);
{
auto s = readString(conn->from);
if (s == "")
throw Error("NAR hash is now mandatory");
info->narHash = Hash::parseAnyPrefixed(s);
}
info->ca = parseContentAddressOpt(readString(conn->from));
info->sigs = readStrings<StringSet>(conn->from);
auto s = readString(conn->from);
assert(s == "");
callback(std::move(info));
} catch (...) { callback.rethrow(); }
}
void addToStore(const ValidPathInfo & info, Source & source,
RepairFlag repair, CheckSigsFlag checkSigs) override
{
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
<< cmdAddToStoreNar
<< printStorePath(info.path)
<< (info.deriver ? printStorePath(*info.deriver) : "")
<< info.narHash.to_string(Base16, false);
worker_proto::write(*this, conn->to, 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
<< cmdImportPaths
<< 1;
try {
copyNAR(source, conn->to);
} catch (...) {
conn->good = false;
throw;
}
conn->to
<< exportMagic
<< printStorePath(info.path);
worker_proto::write(*this, conn->to, 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 narFromPath(const StorePath & path, Sink & sink) override
{
auto conn(connections->get());
conn->to << cmdDumpStorePath << printStorePath(path);
conn->to.flush();
copyNAR(conn->from, sink);
}
std::optional<StorePath> queryPathFromHashPart(const std::string & hashPart) override
{ unsupported("queryPathFromHashPart"); }
StorePath addToStore(const string & name, const Path & srcPath,
FileIngestionMethod method, HashType hashAlgo,
PathFilter & filter, RepairFlag repair) override
{ unsupported("addToStore"); }
StorePath addTextToStore(const string & name, const string & s,
const StorePathSet & references, RepairFlag repair) override
{ unsupported("addTextToStore"); }
private:
void putBuildSettings(Connection & conn)
{
conn.to
<< settings.maxSilentTime
<< settings.buildTimeout;
if (GET_PROTOCOL_MINOR(conn.remoteVersion) >= 2)
conn.to
<< settings.maxLogSize;
if (GET_PROTOCOL_MINOR(conn.remoteVersion) >= 3)
conn.to
<< settings.buildRepeat
<< settings.enforceDeterminism;
}
public:
BuildResult buildDerivation(const StorePath & drvPath, const BasicDerivation & drv,
BuildMode buildMode) override
{
auto conn(connections->get());
conn->to
<< cmdBuildDerivation
<< printStorePath(drvPath);
writeDerivation(conn->to, *this, drv);
putBuildSettings(*conn);
conn->to.flush();
BuildResult status;
status.status = (BuildResult::Status) readInt(conn->from);
conn->from >> status.errorMsg;
if (GET_PROTOCOL_MINOR(conn->remoteVersion) >= 3)
conn->from >> status.timesBuilt >> status.isNonDeterministic >> status.startTime >> status.stopTime;
if (GET_PROTOCOL_MINOR(conn->remoteVersion) >= 6) {
status.builtOutputs = worker_proto::read(*this, conn->from, Phantom<DrvOutputs> {});
}
return status;
}
void buildPaths(const std::vector<DerivedPath> & drvPaths, BuildMode buildMode, std::shared_ptr<Store> evalStore) override
{
if (evalStore && evalStore.get() != this)
throw Error("building on an SSH store is incompatible with '--eval-store'");
auto conn(connections->get());
conn->to << cmdBuildPaths;
Strings ss;
for (auto & p : drvPaths) {
auto sOrDrvPath = StorePathWithOutputs::tryFromDerivedPath(p);
std::visit(overloaded {
[&](StorePathWithOutputs s) {
ss.push_back(s.to_string(*this));
},
[&](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));
},
}, sOrDrvPath);
}
conn->to << ss;
putBuildSettings(*conn);
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 ensurePath(const StorePath & path) override
{ unsupported("ensurePath"); }
void computeFSClosure(const StorePathSet & paths,
StorePathSet & out, bool flipDirection = false,
bool includeOutputs = false, bool includeDerivers = false) override
{
if (flipDirection || includeDerivers) {
Store::computeFSClosure(paths, out, flipDirection, includeOutputs, includeDerivers);
return;
}
auto conn(connections->get());
conn->to
<< cmdQueryClosure
<< includeOutputs;
worker_proto::write(*this, conn->to, paths);
conn->to.flush();
for (auto & i : worker_proto::read(*this, conn->from, Phantom<StorePathSet> {}))
out.insert(i);
}
StorePathSet queryValidPaths(const StorePathSet & paths,
SubstituteFlag maybeSubstitute = NoSubstitute) override
{
auto conn(connections->get());
conn->to
<< cmdQueryValidPaths
<< false // lock
<< maybeSubstitute;
worker_proto::write(*this, conn->to, paths);
conn->to.flush();
return worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
}
void connect() override
{
auto conn(connections->get());
}
unsigned int getProtocol() override
{
auto conn(connections->get());
return conn->remoteVersion;
}
std::optional<const Realisation> queryRealisation(const DrvOutput&) override
// TODO: Implement
{ unsupported("queryRealisation"); }
};
static RegisterStoreImplementation<LegacySSHStore, LegacySSHStoreConfig> regLegacySSHStore;
}