#include "local-store.hh" #include "globals.hh" #include "archive.hh" #include "pathlocks.hh" #include "worker-protocol.hh" #include "derivations.hh" #include "nar-info.hh" #include "references.hh" #include "callback.hh" #include "topo-sort.hh" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if __linux__ #include #include #include #include #include #endif #ifdef __CYGWIN__ #include #endif #include namespace nix { struct LocalStore::State::Stmts { /* Some precompiled SQLite statements. */ SQLiteStmt RegisterValidPath; SQLiteStmt UpdatePathInfo; SQLiteStmt AddReference; SQLiteStmt QueryPathInfo; SQLiteStmt QueryReferences; SQLiteStmt QueryReferrers; SQLiteStmt InvalidatePath; SQLiteStmt AddDerivationOutput; SQLiteStmt RegisterRealisedOutput; SQLiteStmt QueryValidDerivers; SQLiteStmt QueryDerivationOutputs; SQLiteStmt QueryRealisedOutput; SQLiteStmt QueryAllRealisedOutputs; SQLiteStmt QueryPathFromHashPart; SQLiteStmt QueryValidPaths; }; int getSchema(Path schemaPath) { int curSchema = 0; if (pathExists(schemaPath)) { string s = readFile(schemaPath); auto n = string2Int(s); if (!n) throw Error("'%1%' is corrupt", schemaPath); curSchema = *n; } return curSchema; } void migrateCASchema(SQLite& db, Path schemaPath, AutoCloseFD& lockFd) { const int nixCASchemaVersion = 1; int curCASchema = getSchema(schemaPath); if (curCASchema != nixCASchemaVersion) { if (curCASchema > nixCASchemaVersion) { throw Error("current Nix store ca-schema is version %1%, but I only support %2%", curCASchema, nixCASchemaVersion); } if (!lockFile(lockFd.get(), ltWrite, false)) { printInfo("waiting for exclusive access to the Nix store for ca drvs..."); lockFile(lockFd.get(), ltWrite, true); } if (curCASchema == 0) { static const char schema[] = #include "ca-specific-schema.sql.gen.hh" ; db.exec(schema); } writeFile(schemaPath, fmt("%d", nixCASchemaVersion)); lockFile(lockFd.get(), ltRead, true); } } LocalStore::LocalStore(const Params & params) : StoreConfig(params) , LocalFSStoreConfig(params) , LocalStoreConfig(params) , Store(params) , LocalFSStore(params) , realStoreDir_{this, false, rootDir != "" ? rootDir + "/nix/store" : storeDir, "real", "physical path to the Nix store"} , realStoreDir(realStoreDir_) , dbDir(stateDir + "/db") , linksDir(realStoreDir + "/.links") , reservedPath(dbDir + "/reserved") , schemaPath(dbDir + "/schema") , trashDir(realStoreDir + "/trash") , tempRootsDir(stateDir + "/temproots") , fnTempRoots(fmt("%s/%d", tempRootsDir, getpid())) , locksHeld(tokenizeString(getEnv("NIX_HELD_LOCKS").value_or(""))) { auto state(_state.lock()); state->stmts = std::make_unique(); /* Create missing state directories if they don't already exist. */ createDirs(realStoreDir); makeStoreWritable(); createDirs(linksDir); Path profilesDir = stateDir + "/profiles"; createDirs(profilesDir); createDirs(tempRootsDir); createDirs(dbDir); Path gcRootsDir = stateDir + "/gcroots"; if (!pathExists(gcRootsDir)) { createDirs(gcRootsDir); createSymlink(profilesDir, gcRootsDir + "/profiles"); } for (auto & perUserDir : {profilesDir + "/per-user", gcRootsDir + "/per-user"}) { createDirs(perUserDir); if (chmod(perUserDir.c_str(), 0755) == -1) throw SysError("could not set permissions on '%s' to 755", perUserDir); } createUser(getUserName(), getuid()); /* Optionally, create directories and set permissions for a multi-user install. */ if (getuid() == 0 && settings.buildUsersGroup != "") { mode_t perm = 01775; struct group * gr = getgrnam(settings.buildUsersGroup.get().c_str()); if (!gr) printError("warning: the group '%1%' specified in 'build-users-group' does not exist", settings.buildUsersGroup); else { struct stat st; if (stat(realStoreDir.c_str(), &st)) throw SysError("getting attributes of path '%1%'", realStoreDir); if (st.st_uid != 0 || st.st_gid != gr->gr_gid || (st.st_mode & ~S_IFMT) != perm) { if (chown(realStoreDir.c_str(), 0, gr->gr_gid) == -1) throw SysError("changing ownership of path '%1%'", realStoreDir); if (chmod(realStoreDir.c_str(), perm) == -1) throw SysError("changing permissions on path '%1%'", realStoreDir); } } } /* Ensure that the store and its parents are not symlinks. */ if (!settings.allowSymlinkedStore) { Path path = realStoreDir; struct stat st; while (path != "/") { st = lstat(path); if (S_ISLNK(st.st_mode)) throw Error( "the path '%1%' is a symlink; " "this is not allowed for the Nix store and its parent directories", path); path = dirOf(path); } } /* We can't open a SQLite database if the disk is full. Since this prevents the garbage collector from running when it's most needed, we reserve some dummy space that we can free just before doing a garbage collection. */ try { struct stat st; if (stat(reservedPath.c_str(), &st) == -1 || st.st_size != settings.reservedSize) { AutoCloseFD fd = open(reservedPath.c_str(), O_WRONLY | O_CREAT | O_CLOEXEC, 0600); int res = -1; #if HAVE_POSIX_FALLOCATE res = posix_fallocate(fd.get(), 0, settings.reservedSize); #endif if (res == -1) { writeFull(fd.get(), string(settings.reservedSize, 'X')); [[gnu::unused]] auto res2 = ftruncate(fd.get(), settings.reservedSize); } } } catch (SysError & e) { /* don't care about errors */ } /* Acquire the big fat lock in shared mode to make sure that no schema upgrade is in progress. */ Path globalLockPath = dbDir + "/big-lock"; globalLock = openLockFile(globalLockPath.c_str(), true); if (!lockFile(globalLock.get(), ltRead, false)) { printInfo("waiting for the big Nix store lock..."); lockFile(globalLock.get(), ltRead, true); } /* Check the current database schema and if necessary do an upgrade. */ int curSchema = getSchema(); if (curSchema > nixSchemaVersion) throw Error("current Nix store schema is version %1%, but I only support %2%", curSchema, nixSchemaVersion); else if (curSchema == 0) { /* new store */ curSchema = nixSchemaVersion; openDB(*state, true); writeFile(schemaPath, (format("%1%") % nixSchemaVersion).str()); } else if (curSchema < nixSchemaVersion) { if (curSchema < 5) throw Error( "Your Nix store has a database in Berkeley DB format,\n" "which is no longer supported. To convert to the new format,\n" "please upgrade Nix to version 0.12 first."); if (curSchema < 6) throw Error( "Your Nix store has a database in flat file format,\n" "which is no longer supported. To convert to the new format,\n" "please upgrade Nix to version 1.11 first."); if (!lockFile(globalLock.get(), ltWrite, false)) { printInfo("waiting for exclusive access to the Nix store..."); lockFile(globalLock.get(), ltWrite, true); } /* Get the schema version again, because another process may have performed the upgrade already. */ curSchema = getSchema(); if (curSchema < 7) { upgradeStore7(); } openDB(*state, false); if (curSchema < 8) { SQLiteTxn txn(state->db); state->db.exec("alter table ValidPaths add column ultimate integer"); state->db.exec("alter table ValidPaths add column sigs text"); txn.commit(); } if (curSchema < 9) { SQLiteTxn txn(state->db); state->db.exec("drop table FailedPaths"); txn.commit(); } if (curSchema < 10) { SQLiteTxn txn(state->db); state->db.exec("alter table ValidPaths add column ca text"); txn.commit(); } writeFile(schemaPath, (format("%1%") % nixSchemaVersion).str()); lockFile(globalLock.get(), ltRead, true); } else openDB(*state, false); if (settings.isExperimentalFeatureEnabled("ca-derivations")) { migrateCASchema(state->db, dbDir + "/ca-schema", globalLock); } /* Prepare SQL statements. */ state->stmts->RegisterValidPath.create(state->db, "insert into ValidPaths (path, hash, registrationTime, deriver, narSize, ultimate, sigs, ca) values (?, ?, ?, ?, ?, ?, ?, ?);"); state->stmts->UpdatePathInfo.create(state->db, "update ValidPaths set narSize = ?, hash = ?, ultimate = ?, sigs = ?, ca = ? where path = ?;"); state->stmts->AddReference.create(state->db, "insert or replace into Refs (referrer, reference) values (?, ?);"); state->stmts->QueryPathInfo.create(state->db, "select id, hash, registrationTime, deriver, narSize, ultimate, sigs, ca from ValidPaths where path = ?;"); state->stmts->QueryReferences.create(state->db, "select path from Refs join ValidPaths on reference = id where referrer = ?;"); state->stmts->QueryReferrers.create(state->db, "select path from Refs join ValidPaths on referrer = id where reference = (select id from ValidPaths where path = ?);"); state->stmts->InvalidatePath.create(state->db, "delete from ValidPaths where path = ?;"); state->stmts->AddDerivationOutput.create(state->db, "insert or replace into DerivationOutputs (drv, id, path) values (?, ?, ?);"); state->stmts->QueryValidDerivers.create(state->db, "select v.id, v.path from DerivationOutputs d join ValidPaths v on d.drv = v.id where d.path = ?;"); state->stmts->QueryDerivationOutputs.create(state->db, "select id, path from DerivationOutputs where drv = ?;"); // Use "path >= ?" with limit 1 rather than "path like '?%'" to // ensure efficient lookup. state->stmts->QueryPathFromHashPart.create(state->db, "select path from ValidPaths where path >= ? limit 1;"); state->stmts->QueryValidPaths.create(state->db, "select path from ValidPaths"); if (settings.isExperimentalFeatureEnabled("ca-derivations")) { state->stmts->RegisterRealisedOutput.create(state->db, R"( insert or replace into Realisations (drvPath, outputName, outputPath, signatures) values (?, ?, (select id from ValidPaths where path = ?), ?) ; )"); state->stmts->QueryRealisedOutput.create(state->db, R"( select Output.path, Realisations.signatures from Realisations inner join ValidPaths as Output on Output.id = Realisations.outputPath where drvPath = ? and outputName = ? ; )"); state->stmts->QueryAllRealisedOutputs.create(state->db, R"( select outputName, Output.path from Realisations inner join ValidPaths as Output on Output.id = Realisations.outputPath where drvPath = ? ; )"); } } LocalStore::~LocalStore() { std::shared_future future; { auto state(_state.lock()); if (state->gcRunning) future = state->gcFuture; } if (future.valid()) { printInfo("waiting for auto-GC to finish on exit..."); future.get(); } try { auto state(_state.lock()); if (state->fdTempRoots) { state->fdTempRoots = -1; unlink(fnTempRoots.c_str()); } } catch (...) { ignoreException(); } } std::string LocalStore::getUri() { return "local"; } int LocalStore::getSchema() { return nix::getSchema(schemaPath); } void LocalStore::openDB(State & state, bool create) { if (access(dbDir.c_str(), R_OK | W_OK)) throw SysError("Nix database directory '%1%' is not writable", dbDir); /* Open the Nix database. */ string dbPath = dbDir + "/db.sqlite"; auto & db(state.db); state.db = SQLite(dbPath, create); #ifdef __CYGWIN__ /* The cygwin version of sqlite3 has a patch which calls SetDllDirectory("/usr/bin") on init. It was intended to fix extension loading, which we don't use, and the effect of SetDllDirectory is inherited by child processes, and causes libraries to be loaded from /usr/bin instead of $PATH. This breaks quite a few things (e.g. checkPhase on openssh), so we set it back to default behaviour. */ SetDllDirectoryW(L""); #endif /* !!! check whether sqlite has been built with foreign key support */ /* Whether SQLite should fsync(). "Normal" synchronous mode should be safe enough. If the user asks for it, don't sync at all. This can cause database corruption if the system crashes. */ string syncMode = settings.fsyncMetadata ? "normal" : "off"; db.exec("pragma synchronous = " + syncMode); /* Set the SQLite journal mode. WAL mode is fastest, so it's the default. */ string mode = settings.useSQLiteWAL ? "wal" : "truncate"; string prevMode; { SQLiteStmt stmt; stmt.create(db, "pragma main.journal_mode;"); if (sqlite3_step(stmt) != SQLITE_ROW) throwSQLiteError(db, "querying journal mode"); prevMode = string((const char *) sqlite3_column_text(stmt, 0)); } if (prevMode != mode && sqlite3_exec(db, ("pragma main.journal_mode = " + mode + ";").c_str(), 0, 0, 0) != SQLITE_OK) throwSQLiteError(db, "setting journal mode"); /* Increase the auto-checkpoint interval to 40000 pages. This seems enough to ensure that instantiating the NixOS system derivation is done in a single fsync(). */ if (mode == "wal" && sqlite3_exec(db, "pragma wal_autocheckpoint = 40000;", 0, 0, 0) != SQLITE_OK) throwSQLiteError(db, "setting autocheckpoint interval"); /* Initialise the database schema, if necessary. */ if (create) { static const char schema[] = #include "schema.sql.gen.hh" ; db.exec(schema); } } /* To improve purity, users may want to make the Nix store a read-only bind mount. So make the Nix store writable for this process. */ void LocalStore::makeStoreWritable() { #if __linux__ if (getuid() != 0) return; /* Check if /nix/store is on a read-only mount. */ struct statvfs stat; if (statvfs(realStoreDir.c_str(), &stat) != 0) throw SysError("getting info about the Nix store mount point"); if (stat.f_flag & ST_RDONLY) { if (unshare(CLONE_NEWNS) == -1) throw SysError("setting up a private mount namespace"); if (mount(0, realStoreDir.c_str(), "none", MS_REMOUNT | MS_BIND, 0) == -1) throw SysError("remounting %1% writable", realStoreDir); } #endif } const time_t mtimeStore = 1; /* 1 second into the epoch */ static void canonicaliseTimestampAndPermissions(const Path & path, const struct stat & st) { if (!S_ISLNK(st.st_mode)) { /* Mask out all type related bits. */ mode_t mode = st.st_mode & ~S_IFMT; if (mode != 0444 && mode != 0555) { mode = (st.st_mode & S_IFMT) | 0444 | (st.st_mode & S_IXUSR ? 0111 : 0); if (chmod(path.c_str(), mode) == -1) throw SysError("changing mode of '%1%' to %2$o", path, mode); } } if (st.st_mtime != mtimeStore) { struct timeval times[2]; times[0].tv_sec = st.st_atime; times[0].tv_usec = 0; times[1].tv_sec = mtimeStore; times[1].tv_usec = 0; #if HAVE_LUTIMES if (lutimes(path.c_str(), times) == -1) if (errno != ENOSYS || (!S_ISLNK(st.st_mode) && utimes(path.c_str(), times) == -1)) #else if (!S_ISLNK(st.st_mode) && utimes(path.c_str(), times) == -1) #endif throw SysError("changing modification time of '%1%'", path); } } void canonicaliseTimestampAndPermissions(const Path & path) { canonicaliseTimestampAndPermissions(path, lstat(path)); } static void canonicalisePathMetaData_(const Path & path, uid_t fromUid, InodesSeen & inodesSeen) { checkInterrupt(); #if __APPLE__ /* Remove flags, in particular UF_IMMUTABLE which would prevent the file from being garbage-collected. FIXME: Use setattrlist() to remove other attributes as well. */ if (lchflags(path.c_str(), 0)) { if (errno != ENOTSUP) throw SysError("clearing flags of path '%1%'", path); } #endif auto st = lstat(path); /* Really make sure that the path is of a supported type. */ if (!(S_ISREG(st.st_mode) || S_ISDIR(st.st_mode) || S_ISLNK(st.st_mode))) throw Error("file '%1%' has an unsupported type", path); #if __linux__ /* Remove extended attributes / ACLs. */ ssize_t eaSize = llistxattr(path.c_str(), nullptr, 0); if (eaSize < 0) { if (errno != ENOTSUP && errno != ENODATA) throw SysError("querying extended attributes of '%s'", path); } else if (eaSize > 0) { std::vector eaBuf(eaSize); if ((eaSize = llistxattr(path.c_str(), eaBuf.data(), eaBuf.size())) < 0) throw SysError("querying extended attributes of '%s'", path); for (auto & eaName: tokenizeString(std::string(eaBuf.data(), eaSize), std::string("\000", 1))) { /* Ignore SELinux security labels since these cannot be removed even by root. */ if (eaName == "security.selinux") continue; if (lremovexattr(path.c_str(), eaName.c_str()) == -1) throw SysError("removing extended attribute '%s' from '%s'", eaName, path); } } #endif /* Fail if the file is not owned by the build user. This prevents us from messing up the ownership/permissions of files hard-linked into the output (e.g. "ln /etc/shadow $out/foo"). However, ignore files that we chown'ed ourselves previously to ensure that we don't fail on hard links within the same build (i.e. "touch $out/foo; ln $out/foo $out/bar"). */ if (fromUid != (uid_t) -1 && st.st_uid != fromUid) { if (S_ISDIR(st.st_mode) || !inodesSeen.count(Inode(st.st_dev, st.st_ino))) throw BuildError("invalid ownership on file '%1%'", path); mode_t mode = st.st_mode & ~S_IFMT; assert(S_ISLNK(st.st_mode) || (st.st_uid == geteuid() && (mode == 0444 || mode == 0555) && st.st_mtime == mtimeStore)); return; } inodesSeen.insert(Inode(st.st_dev, st.st_ino)); canonicaliseTimestampAndPermissions(path, st); /* Change ownership to the current uid. If it's a symlink, use lchown if available, otherwise don't bother. Wrong ownership of a symlink doesn't matter, since the owning user can't change the symlink and can't delete it because the directory is not writable. The only exception is top-level paths in the Nix store (since that directory is group-writable for the Nix build users group); we check for this case below. */ if (st.st_uid != geteuid()) { #if HAVE_LCHOWN if (lchown(path.c_str(), geteuid(), getegid()) == -1) #else if (!S_ISLNK(st.st_mode) && chown(path.c_str(), geteuid(), getegid()) == -1) #endif throw SysError("changing owner of '%1%' to %2%", path, geteuid()); } if (S_ISDIR(st.st_mode)) { DirEntries entries = readDirectory(path); for (auto & i : entries) canonicalisePathMetaData_(path + "/" + i.name, fromUid, inodesSeen); } } void canonicalisePathMetaData(const Path & path, uid_t fromUid, InodesSeen & inodesSeen) { canonicalisePathMetaData_(path, fromUid, inodesSeen); /* On platforms that don't have lchown(), the top-level path can't be a symlink, since we can't change its ownership. */ auto st = lstat(path); if (st.st_uid != geteuid()) { assert(S_ISLNK(st.st_mode)); throw Error("wrong ownership of top-level store path '%1%'", path); } } void canonicalisePathMetaData(const Path & path, uid_t fromUid) { InodesSeen inodesSeen; canonicalisePathMetaData(path, fromUid, inodesSeen); } void LocalStore::checkDerivationOutputs(const StorePath & drvPath, const Derivation & drv) { assert(drvPath.isDerivation()); std::string drvName(drvPath.name()); drvName = string(drvName, 0, drvName.size() - drvExtension.size()); auto envHasRightPath = [&](const StorePath & actual, const std::string & varName) { auto j = drv.env.find(varName); if (j == drv.env.end() || parseStorePath(j->second) != actual) throw Error("derivation '%s' has incorrect environment variable '%s', should be '%s'", printStorePath(drvPath), varName, printStorePath(actual)); }; // Don't need the answer, but do this anyways to assert is proper // combination. The code below is more general and naturally allows // combinations that are currently prohibited. drv.type(); std::optional h; for (auto & i : drv.outputs) { std::visit(overloaded { [&](DerivationOutputInputAddressed doia) { if (!h) { // somewhat expensive so we do lazily auto temp = hashDerivationModulo(*this, drv, true); h = std::get(temp); } StorePath recomputed = makeOutputPath(i.first, *h, drvName); if (doia.path != recomputed) throw Error("derivation '%s' has incorrect output '%s', should be '%s'", printStorePath(drvPath), printStorePath(doia.path), printStorePath(recomputed)); envHasRightPath(doia.path, i.first); }, [&](DerivationOutputCAFixed dof) { StorePath path = makeFixedOutputPath(dof.hash.method, dof.hash.hash, drvName); envHasRightPath(path, i.first); }, [&](DerivationOutputCAFloating _) { /* Nothing to check */ }, [&](DerivationOutputDeferred) { }, }, i.second.output); } } void LocalStore::registerDrvOutput(const Realisation & info, CheckSigsFlag checkSigs) { settings.requireExperimentalFeature("ca-derivations"); if (checkSigs == NoCheckSigs || !realisationIsUntrusted(info)) registerDrvOutput(info); else throw Error("cannot register realisation '%s' because it lacks a valid signature", info.outPath.to_string()); } void LocalStore::registerDrvOutput(const Realisation & info) { settings.requireExperimentalFeature("ca-derivations"); auto state(_state.lock()); retrySQLite([&]() { state->stmts->RegisterRealisedOutput.use() (info.id.strHash()) (info.id.outputName) (printStorePath(info.outPath)) (concatStringsSep(" ", info.signatures)) .exec(); }); } void LocalStore::cacheDrvOutputMapping(State & state, const uint64_t deriver, const string & outputName, const StorePath & output) { retrySQLite([&]() { state.stmts->AddDerivationOutput.use() (deriver) (outputName) (printStorePath(output)) .exec(); }); } uint64_t LocalStore::addValidPath(State & state, const ValidPathInfo & info, bool checkOutputs) { if (info.ca.has_value() && !info.isContentAddressed(*this)) throw Error("cannot add path '%s' to the Nix store because it claims to be content-addressed but isn't", printStorePath(info.path)); state.stmts->RegisterValidPath.use() (printStorePath(info.path)) (info.narHash.to_string(Base16, true)) (info.registrationTime == 0 ? time(0) : info.registrationTime) (info.deriver ? printStorePath(*info.deriver) : "", (bool) info.deriver) (info.narSize, info.narSize != 0) (info.ultimate ? 1 : 0, info.ultimate) (concatStringsSep(" ", info.sigs), !info.sigs.empty()) (renderContentAddress(info.ca), (bool) info.ca) .exec(); uint64_t id = state.db.getLastInsertedRowId(); /* If this is a derivation, then store the derivation outputs in the database. This is useful for the garbage collector: it can efficiently query whether a path is an output of some derivation. */ if (info.path.isDerivation()) { auto drv = readInvalidDerivation(info.path); /* Verify that the output paths in the derivation are correct (i.e., follow the scheme for computing output paths from derivations). Note that if this throws an error, then the DB transaction is rolled back, so the path validity registration above is undone. */ if (checkOutputs) checkDerivationOutputs(info.path, drv); for (auto & i : drv.outputsAndOptPaths(*this)) { /* Floating CA derivations have indeterminate output paths until they are built, so don't register anything in that case */ if (i.second.second) cacheDrvOutputMapping(state, id, i.first, *i.second.second); } } { auto state_(Store::state.lock()); state_->pathInfoCache.upsert(std::string(info.path.hashPart()), PathInfoCacheValue{ .value = std::make_shared(info) }); } return id; } void LocalStore::queryPathInfoUncached(const StorePath & path, Callback> callback) noexcept { try { callback(retrySQLite>([&]() { auto state(_state.lock()); return queryPathInfoInternal(*state, path); })); } catch (...) { callback.rethrow(); } } std::shared_ptr LocalStore::queryPathInfoInternal(State & state, const StorePath & path) { /* Get the path info. */ auto useQueryPathInfo(state.stmts->QueryPathInfo.use()(printStorePath(path))); if (!useQueryPathInfo.next()) return std::shared_ptr(); auto id = useQueryPathInfo.getInt(0); auto narHash = Hash::dummy; try { narHash = Hash::parseAnyPrefixed(useQueryPathInfo.getStr(1)); } catch (BadHash & e) { throw Error("invalid-path entry for '%s': %s", printStorePath(path), e.what()); } auto info = std::make_shared(path, narHash); info->id = id; info->registrationTime = useQueryPathInfo.getInt(2); auto s = (const char *) sqlite3_column_text(state.stmts->QueryPathInfo, 3); if (s) info->deriver = parseStorePath(s); /* Note that narSize = NULL yields 0. */ info->narSize = useQueryPathInfo.getInt(4); info->ultimate = useQueryPathInfo.getInt(5) == 1; s = (const char *) sqlite3_column_text(state.stmts->QueryPathInfo, 6); if (s) info->sigs = tokenizeString(s, " "); s = (const char *) sqlite3_column_text(state.stmts->QueryPathInfo, 7); if (s) info->ca = parseContentAddressOpt(s); /* Get the references. */ auto useQueryReferences(state.stmts->QueryReferences.use()(info->id)); while (useQueryReferences.next()) info->references.insert(parseStorePath(useQueryReferences.getStr(0))); return info; } /* Update path info in the database. */ void LocalStore::updatePathInfo(State & state, const ValidPathInfo & info) { state.stmts->UpdatePathInfo.use() (info.narSize, info.narSize != 0) (info.narHash.to_string(Base16, true)) (info.ultimate ? 1 : 0, info.ultimate) (concatStringsSep(" ", info.sigs), !info.sigs.empty()) (renderContentAddress(info.ca), (bool) info.ca) (printStorePath(info.path)) .exec(); } uint64_t LocalStore::queryValidPathId(State & state, const StorePath & path) { auto use(state.stmts->QueryPathInfo.use()(printStorePath(path))); if (!use.next()) throw InvalidPath("path '%s' is not valid", printStorePath(path)); return use.getInt(0); } bool LocalStore::isValidPath_(State & state, const StorePath & path) { return state.stmts->QueryPathInfo.use()(printStorePath(path)).next(); } bool LocalStore::isValidPathUncached(const StorePath & path) { return retrySQLite([&]() { auto state(_state.lock()); return isValidPath_(*state, path); }); } StorePathSet LocalStore::queryValidPaths(const StorePathSet & paths, SubstituteFlag maybeSubstitute) { StorePathSet res; for (auto & i : paths) if (isValidPath(i)) res.insert(i); return res; } StorePathSet LocalStore::queryAllValidPaths() { return retrySQLite([&]() { auto state(_state.lock()); auto use(state->stmts->QueryValidPaths.use()); StorePathSet res; while (use.next()) res.insert(parseStorePath(use.getStr(0))); return res; }); } void LocalStore::queryReferrers(State & state, const StorePath & path, StorePathSet & referrers) { auto useQueryReferrers(state.stmts->QueryReferrers.use()(printStorePath(path))); while (useQueryReferrers.next()) referrers.insert(parseStorePath(useQueryReferrers.getStr(0))); } void LocalStore::queryReferrers(const StorePath & path, StorePathSet & referrers) { return retrySQLite([&]() { auto state(_state.lock()); queryReferrers(*state, path, referrers); }); } StorePathSet LocalStore::queryValidDerivers(const StorePath & path) { return retrySQLite([&]() { auto state(_state.lock()); auto useQueryValidDerivers(state->stmts->QueryValidDerivers.use()(printStorePath(path))); StorePathSet derivers; while (useQueryValidDerivers.next()) derivers.insert(parseStorePath(useQueryValidDerivers.getStr(1))); return derivers; }); } std::map> LocalStore::queryPartialDerivationOutputMap(const StorePath & path_) { auto path = path_; auto outputs = retrySQLite>>([&]() { auto state(_state.lock()); std::map> outputs; uint64_t drvId; drvId = queryValidPathId(*state, path); auto use(state->stmts->QueryDerivationOutputs.use()(drvId)); while (use.next()) outputs.insert_or_assign( use.getStr(0), parseStorePath(use.getStr(1))); return outputs; }); if (!settings.isExperimentalFeatureEnabled("ca-derivations")) return outputs; auto drv = readInvalidDerivation(path); auto drvHashes = staticOutputHashes(*this, drv); for (auto& [outputName, hash] : drvHashes) { auto realisation = queryRealisation(DrvOutput{hash, outputName}); if (realisation) outputs.insert_or_assign(outputName, realisation->outPath); else outputs.insert({outputName, std::nullopt}); } return outputs; } std::optional LocalStore::queryPathFromHashPart(const std::string & hashPart) { if (hashPart.size() != StorePath::HashLen) throw Error("invalid hash part"); Path prefix = storeDir + "/" + hashPart; return retrySQLite>([&]() -> std::optional { auto state(_state.lock()); auto useQueryPathFromHashPart(state->stmts->QueryPathFromHashPart.use()(prefix)); if (!useQueryPathFromHashPart.next()) return {}; const char * s = (const char *) sqlite3_column_text(state->stmts->QueryPathFromHashPart, 0); if (s && prefix.compare(0, prefix.size(), s, prefix.size()) == 0) return parseStorePath(s); return {}; }); } StorePathSet LocalStore::querySubstitutablePaths(const StorePathSet & paths) { if (!settings.useSubstitutes) return StorePathSet(); StorePathSet remaining; for (auto & i : paths) remaining.insert(i); StorePathSet res; for (auto & sub : getDefaultSubstituters()) { if (remaining.empty()) break; if (sub->storeDir != storeDir) continue; if (!sub->wantMassQuery) continue; auto valid = sub->queryValidPaths(remaining); StorePathSet remaining2; for (auto & path : remaining) if (valid.count(path)) res.insert(path); else remaining2.insert(path); std::swap(remaining, remaining2); } return res; } void LocalStore::querySubstitutablePathInfos(const StorePathCAMap & paths, SubstitutablePathInfos & infos) { if (!settings.useSubstitutes) return; for (auto & sub : getDefaultSubstituters()) { for (auto & path : paths) { auto subPath(path.first); // recompute store path so that we can use a different store root if (path.second) { subPath = makeFixedOutputPathFromCA(path.first.name(), *path.second); if (sub->storeDir == storeDir) assert(subPath == path.first); if (subPath != path.first) debug("replaced path '%s' with '%s' for substituter '%s'", printStorePath(path.first), sub->printStorePath(subPath), sub->getUri()); } else if (sub->storeDir != storeDir) continue; debug("checking substituter '%s' for path '%s'", sub->getUri(), sub->printStorePath(subPath)); try { auto info = sub->queryPathInfo(subPath); if (sub->storeDir != storeDir && !(info->isContentAddressed(*sub) && info->references.empty())) continue; auto narInfo = std::dynamic_pointer_cast( std::shared_ptr(info)); infos.insert_or_assign(path.first, SubstitutablePathInfo{ info->deriver, info->references, narInfo ? narInfo->fileSize : 0, info->narSize}); } catch (InvalidPath &) { } catch (SubstituterDisabled &) { } catch (Error & e) { if (settings.tryFallback) logError(e.info()); else throw; } } } } void LocalStore::registerValidPath(const ValidPathInfo & info) { registerValidPaths({{info.path, info}}); } void LocalStore::registerValidPaths(const ValidPathInfos & infos) { /* SQLite will fsync by default, but the new valid paths may not be fsync-ed. So some may want to fsync them before registering the validity, at the expense of some speed of the path registering operation. */ if (settings.syncBeforeRegistering) sync(); return retrySQLite([&]() { auto state(_state.lock()); SQLiteTxn txn(state->db); StorePathSet paths; for (auto & [_, i] : infos) { assert(i.narHash.type == htSHA256); if (isValidPath_(*state, i.path)) updatePathInfo(*state, i); else addValidPath(*state, i, false); paths.insert(i.path); } for (auto & [_, i] : infos) { auto referrer = queryValidPathId(*state, i.path); for (auto & j : i.references) state->stmts->AddReference.use()(referrer)(queryValidPathId(*state, j)).exec(); } /* Check that the derivation outputs are correct. We can't do this in addValidPath() above, because the references might not be valid yet. */ for (auto & [_, i] : infos) if (i.path.isDerivation()) { // FIXME: inefficient; we already loaded the derivation in addValidPath(). checkDerivationOutputs(i.path, readInvalidDerivation(i.path)); } /* Do a topological sort of the paths. This will throw an error if a cycle is detected and roll back the transaction. Cycles can only occur when a derivation has multiple outputs. */ topoSort(paths, {[&](const StorePath & path) { auto i = infos.find(path); return i == infos.end() ? StorePathSet() : i->second.references; }}, {[&](const StorePath & path, const StorePath & parent) { return BuildError( "cycle detected in the references of '%s' from '%s'", printStorePath(path), printStorePath(parent)); }}); txn.commit(); }); } /* Invalidate a path. The caller is responsible for checking that there are no referrers. */ void LocalStore::invalidatePath(State & state, const StorePath & path) { debug("invalidating path '%s'", printStorePath(path)); state.stmts->InvalidatePath.use()(printStorePath(path)).exec(); /* Note that the foreign key constraints on the Refs table take care of deleting the references entries for `path'. */ { auto state_(Store::state.lock()); state_->pathInfoCache.erase(std::string(path.hashPart())); } } const PublicKeys & LocalStore::getPublicKeys() { auto state(_state.lock()); if (!state->publicKeys) state->publicKeys = std::make_unique(getDefaultPublicKeys()); return *state->publicKeys; } bool LocalStore::pathInfoIsUntrusted(const ValidPathInfo & info) { return requireSigs && !info.checkSignatures(*this, getPublicKeys()); } bool LocalStore::realisationIsUntrusted(const Realisation & realisation) { return requireSigs && !realisation.checkSignatures(getPublicKeys()); } void LocalStore::addToStore(const ValidPathInfo & info, Source & source, RepairFlag repair, CheckSigsFlag checkSigs) { if (checkSigs && pathInfoIsUntrusted(info)) throw Error("cannot add path '%s' because it lacks a valid signature", printStorePath(info.path)); addTempRoot(info.path); if (repair || !isValidPath(info.path)) { PathLocks outputLock; auto realPath = Store::toRealPath(info.path); /* Lock the output path. But don't lock if we're being called from a build hook (whose parent process already acquired a lock on this path). */ if (!locksHeld.count(printStorePath(info.path))) outputLock.lockPaths({realPath}); if (repair || !isValidPath(info.path)) { deletePath(realPath); // text hashing has long been allowed to have non-self-references because it is used for drv files. bool refersToSelf = info.references.count(info.path) > 0; if (info.ca.has_value() && !info.references.empty() && !(std::holds_alternative(*info.ca) && !refersToSelf)) settings.requireExperimentalFeature("ca-references"); /* While restoring the path from the NAR, compute the hash of the NAR. */ HashSink hashSink(htSHA256); TeeSource wrapperSource { source, hashSink }; restorePath(realPath, wrapperSource); auto hashResult = hashSink.finish(); if (hashResult.first != info.narHash) throw Error("hash mismatch importing path '%s';\n specified: %s\n got: %s", printStorePath(info.path), info.narHash.to_string(Base32, true), hashResult.first.to_string(Base32, true)); if (hashResult.second != info.narSize) throw Error("size mismatch importing path '%s';\n specified: %s\n got: %s", printStorePath(info.path), info.narSize, hashResult.second); autoGC(); canonicalisePathMetaData(realPath, -1); optimisePath(realPath); // FIXME: combine with hashPath() registerValidPath(info); } outputLock.setDeletion(true); } } StorePath LocalStore::addToStoreFromDump(Source & source0, const string & name, FileIngestionMethod method, HashType hashAlgo, RepairFlag repair) { /* For computing the store path. */ auto hashSink = std::make_unique(hashAlgo); TeeSource source { source0, *hashSink }; /* Read the source path into memory, but only if it's up to narBufferSize bytes. If it's larger, write it to a temporary location in the Nix store. If the subsequently computed destination store path is already valid, we just delete the temporary path. Otherwise, we move it to the destination store path. */ bool inMemory = false; std::string dump; /* Fill out buffer, and decide whether we are working strictly in memory based on whether we break out because the buffer is full or the original source is empty */ while (dump.size() < settings.narBufferSize) { auto oldSize = dump.size(); constexpr size_t chunkSize = 65536; auto want = std::min(chunkSize, settings.narBufferSize - oldSize); dump.resize(oldSize + want); auto got = 0; try { got = source.read(dump.data() + oldSize, want); } catch (EndOfFile &) { inMemory = true; break; } dump.resize(oldSize + got); } std::unique_ptr delTempDir; Path tempPath; if (!inMemory) { /* Drain what we pulled so far, and then keep on pulling */ StringSource dumpSource { dump }; ChainSource bothSource { dumpSource, source }; auto tempDir = createTempDir(realStoreDir, "add"); delTempDir = std::make_unique(tempDir); tempPath = tempDir + "/x"; if (method == FileIngestionMethod::Recursive) restorePath(tempPath, bothSource); else writeFile(tempPath, bothSource); dump.clear(); } auto [hash, size] = hashSink->finish(); auto dstPath = makeFixedOutputPath(method, hash, name); addTempRoot(dstPath); if (repair || !isValidPath(dstPath)) { /* The first check above is an optimisation to prevent unnecessary lock acquisition. */ auto realPath = Store::toRealPath(dstPath); PathLocks outputLock({realPath}); if (repair || !isValidPath(dstPath)) { deletePath(realPath); autoGC(); if (inMemory) { StringSource dumpSource { dump }; /* Restore from the NAR in memory. */ if (method == FileIngestionMethod::Recursive) restorePath(realPath, dumpSource); else writeFile(realPath, dumpSource); } else { /* Move the temporary path we restored above. */ if (rename(tempPath.c_str(), realPath.c_str())) throw Error("renaming '%s' to '%s'", tempPath, realPath); } /* For computing the nar hash. In recursive SHA-256 mode, this is the same as the store hash, so no need to do it again. */ auto narHash = std::pair { hash, size }; if (method != FileIngestionMethod::Recursive || hashAlgo != htSHA256) { HashSink narSink { htSHA256 }; dumpPath(realPath, narSink); narHash = narSink.finish(); } canonicalisePathMetaData(realPath, -1); // FIXME: merge into restorePath optimisePath(realPath); ValidPathInfo info { dstPath, narHash.first }; info.narSize = narHash.second; info.ca = FixedOutputHash { .method = method, .hash = hash }; registerValidPath(info); } outputLock.setDeletion(true); } return dstPath; } StorePath LocalStore::addTextToStore(const string & name, const string & s, const StorePathSet & references, RepairFlag repair) { auto hash = hashString(htSHA256, s); auto dstPath = makeTextPath(name, hash, references); addTempRoot(dstPath); if (repair || !isValidPath(dstPath)) { auto realPath = Store::toRealPath(dstPath); PathLocks outputLock({realPath}); if (repair || !isValidPath(dstPath)) { deletePath(realPath); autoGC(); writeFile(realPath, s); canonicalisePathMetaData(realPath, -1); StringSink sink; dumpString(s, sink); auto narHash = hashString(htSHA256, *sink.s); optimisePath(realPath); ValidPathInfo info { dstPath, narHash }; info.narSize = sink.s->size(); info.references = references; info.ca = TextHash { .hash = hash }; registerValidPath(info); } outputLock.setDeletion(true); } return dstPath; } /* Create a temporary directory in the store that won't be garbage-collected. */ Path LocalStore::createTempDirInStore() { Path tmpDir; do { /* There is a slight possibility that `tmpDir' gets deleted by the GC between createTempDir() and addTempRoot(), so repeat until `tmpDir' exists. */ tmpDir = createTempDir(realStoreDir); addTempRoot(parseStorePath(tmpDir)); } while (!pathExists(tmpDir)); return tmpDir; } void LocalStore::invalidatePathChecked(const StorePath & path) { retrySQLite([&]() { auto state(_state.lock()); SQLiteTxn txn(state->db); if (isValidPath_(*state, path)) { StorePathSet referrers; queryReferrers(*state, path, referrers); referrers.erase(path); /* ignore self-references */ if (!referrers.empty()) throw PathInUse("cannot delete path '%s' because it is in use by %s", printStorePath(path), showPaths(referrers)); invalidatePath(*state, path); } txn.commit(); }); } bool LocalStore::verifyStore(bool checkContents, RepairFlag repair) { printInfo(format("reading the Nix store...")); bool errors = false; /* Acquire the global GC lock to get a consistent snapshot of existing and valid paths. */ AutoCloseFD fdGCLock = openGCLock(ltWrite); StringSet store; for (auto & i : readDirectory(realStoreDir)) store.insert(i.name); /* Check whether all valid paths actually exist. */ printInfo("checking path existence..."); StorePathSet validPaths; PathSet done; fdGCLock = -1; for (auto & i : queryAllValidPaths()) verifyPath(printStorePath(i), store, done, validPaths, repair, errors); /* Optionally, check the content hashes (slow). */ if (checkContents) { printInfo("checking link hashes..."); for (auto & link : readDirectory(linksDir)) { printMsg(lvlTalkative, "checking contents of '%s'", link.name); Path linkPath = linksDir + "/" + link.name; string hash = hashPath(htSHA256, linkPath).first.to_string(Base32, false); if (hash != link.name) { printError("link '%s' was modified! expected hash '%s', got '%s'", linkPath, link.name, hash); if (repair) { if (unlink(linkPath.c_str()) == 0) printInfo("removed link '%s'", linkPath); else throw SysError("removing corrupt link '%s'", linkPath); } else { errors = true; } } } printInfo("checking store hashes..."); Hash nullHash(htSHA256); for (auto & i : validPaths) { try { auto info = std::const_pointer_cast(std::shared_ptr(queryPathInfo(i))); /* Check the content hash (optionally - slow). */ printMsg(lvlTalkative, "checking contents of '%s'", printStorePath(i)); auto hashSink = HashSink(info->narHash.type); dumpPath(Store::toRealPath(i), hashSink); auto current = hashSink.finish(); if (info->narHash != nullHash && info->narHash != current.first) { printError("path '%s' was modified! expected hash '%s', got '%s'", printStorePath(i), info->narHash.to_string(Base32, true), current.first.to_string(Base32, true)); if (repair) repairPath(i); else errors = true; } else { bool update = false; /* Fill in missing hashes. */ if (info->narHash == nullHash) { printInfo("fixing missing hash on '%s'", printStorePath(i)); info->narHash = current.first; update = true; } /* Fill in missing narSize fields (from old stores). */ if (info->narSize == 0) { printInfo("updating size field on '%s' to %s", printStorePath(i), current.second); info->narSize = current.second; update = true; } if (update) { auto state(_state.lock()); updatePathInfo(*state, *info); } } } catch (Error & e) { /* It's possible that the path got GC'ed, so ignore errors on invalid paths. */ if (isValidPath(i)) logError(e.info()); else warn(e.msg()); errors = true; } } } return errors; } void LocalStore::verifyPath(const Path & pathS, const StringSet & store, PathSet & done, StorePathSet & validPaths, RepairFlag repair, bool & errors) { checkInterrupt(); if (!done.insert(pathS).second) return; if (!isStorePath(pathS)) { printError("path '%s' is not in the Nix store", pathS); return; } auto path = parseStorePath(pathS); if (!store.count(std::string(path.to_string()))) { /* Check any referrers first. If we can invalidate them first, then we can invalidate this path as well. */ bool canInvalidate = true; StorePathSet referrers; queryReferrers(path, referrers); for (auto & i : referrers) if (i != path) { verifyPath(printStorePath(i), store, done, validPaths, repair, errors); if (validPaths.count(i)) canInvalidate = false; } if (canInvalidate) { printInfo("path '%s' disappeared, removing from database...", pathS); auto state(_state.lock()); invalidatePath(*state, path); } else { printError("path '%s' disappeared, but it still has valid referrers!", pathS); if (repair) try { repairPath(path); } catch (Error & e) { logWarning(e.info()); errors = true; } else errors = true; } return; } validPaths.insert(std::move(path)); } unsigned int LocalStore::getProtocol() { return PROTOCOL_VERSION; } #if defined(FS_IOC_SETFLAGS) && defined(FS_IOC_GETFLAGS) && defined(FS_IMMUTABLE_FL) static void makeMutable(const Path & path) { checkInterrupt(); auto st = lstat(path); if (!S_ISDIR(st.st_mode) && !S_ISREG(st.st_mode)) return; if (S_ISDIR(st.st_mode)) { for (auto & i : readDirectory(path)) makeMutable(path + "/" + i.name); } /* The O_NOFOLLOW is important to prevent us from changing the mutable bit on the target of a symlink (which would be a security hole). */ AutoCloseFD fd = open(path.c_str(), O_RDONLY | O_NOFOLLOW | O_CLOEXEC); if (fd == -1) { if (errno == ELOOP) return; // it's a symlink throw SysError("opening file '%1%'", path); } unsigned int flags = 0, old; /* Silently ignore errors getting/setting the immutable flag so that we work correctly on filesystems that don't support it. */ if (ioctl(fd, FS_IOC_GETFLAGS, &flags)) return; old = flags; flags &= ~FS_IMMUTABLE_FL; if (old == flags) return; if (ioctl(fd, FS_IOC_SETFLAGS, &flags)) return; } /* Upgrade from schema 6 (Nix 0.15) to schema 7 (Nix >= 1.3). */ void LocalStore::upgradeStore7() { if (getuid() != 0) return; printInfo("removing immutable bits from the Nix store (this may take a while)..."); makeMutable(realStoreDir); } #else void LocalStore::upgradeStore7() { } #endif void LocalStore::vacuumDB() { auto state(_state.lock()); state->db.exec("vacuum"); } void LocalStore::addSignatures(const StorePath & storePath, const StringSet & sigs) { retrySQLite([&]() { auto state(_state.lock()); SQLiteTxn txn(state->db); auto info = std::const_pointer_cast(queryPathInfoInternal(*state, storePath)); info->sigs.insert(sigs.begin(), sigs.end()); updatePathInfo(*state, *info); txn.commit(); }); } void LocalStore::signRealisation(Realisation & realisation) { // FIXME: keep secret keys in memory. auto secretKeyFiles = settings.secretKeyFiles; for (auto & secretKeyFile : secretKeyFiles.get()) { SecretKey secretKey(readFile(secretKeyFile)); realisation.sign(secretKey); } } void LocalStore::signPathInfo(ValidPathInfo & info) { // FIXME: keep secret keys in memory. auto secretKeyFiles = settings.secretKeyFiles; for (auto & secretKeyFile : secretKeyFiles.get()) { SecretKey secretKey(readFile(secretKeyFile)); info.sign(*this, secretKey); } } void LocalStore::createUser(const std::string & userName, uid_t userId) { for (auto & dir : { fmt("%s/profiles/per-user/%s", stateDir, userName), fmt("%s/gcroots/per-user/%s", stateDir, userName) }) { createDirs(dir); if (chmod(dir.c_str(), 0755) == -1) throw SysError("changing permissions of directory '%s'", dir); if (chown(dir.c_str(), userId, getgid()) == -1) throw SysError("changing owner of directory '%s'", dir); } } std::optional LocalStore::queryRealisation( const DrvOutput& id) { typedef std::optional Ret; return retrySQLite([&]() -> Ret { auto state(_state.lock()); auto use(state->stmts->QueryRealisedOutput.use()(id.strHash())( id.outputName)); if (!use.next()) return std::nullopt; auto outputPath = parseStorePath(use.getStr(0)); auto signatures = tokenizeString(use.getStr(1)); return Ret{Realisation{ .id = id, .outPath = outputPath, .signatures = signatures}}; }); } } // namespace nix