Java tutorial
/* * Copyright (c) 2009 - 2015 Deutsches Elektronen-Synchroton, * Member of the Helmholtz Association, (DESY), HAMBURG, GERMANY * * This library is free software; you can redistribute it and/or modify * it under the terms of the GNU Library General Public License as * published by the Free Software Foundation; either version 2 of the * License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this program (see the file COPYING.LIB for more * details); if not, write to the Free Software Foundation, Inc., * 675 Mass Ave, Cambridge, MA 02139, USA. */ package org.dcache.nfs.chimera; import com.google.common.base.Function; import com.google.common.collect.Lists; import com.google.common.primitives.Longs; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import javax.security.auth.Subject; import java.io.IOException; import java.nio.charset.StandardCharsets; import java.util.ArrayList; import java.util.List; import org.dcache.acl.ACE; import org.dcache.acl.enums.AceFlags; import org.dcache.acl.enums.AceType; import org.dcache.acl.enums.Who; import org.dcache.auth.Subjects; import org.dcache.chimera.ChimeraFsException; import org.dcache.chimera.DirNotEmptyHimeraFsException; import org.dcache.chimera.DirectoryStreamHelper; import org.dcache.chimera.FileExistsChimeraFsException; import org.dcache.chimera.FileNotFoundHimeraFsException; import org.dcache.chimera.FsInode; import org.dcache.chimera.FsInodeType; import org.dcache.chimera.HimeraDirectoryEntry; import org.dcache.chimera.InvalidArgumentChimeraException; import org.dcache.chimera.IsDirChimeraException; import org.dcache.chimera.JdbcFs; import org.dcache.chimera.NotDirChimeraException; import org.dcache.chimera.StorageGenericLocation; import org.dcache.nfs.status.BadOwnerException; import org.dcache.nfs.status.ExistException; import org.dcache.nfs.status.InvalException; import org.dcache.nfs.status.IsDirException; import org.dcache.nfs.status.NfsIoException; import org.dcache.nfs.status.NoEntException; import org.dcache.nfs.status.NotDirException; import org.dcache.nfs.status.NotEmptyException; import org.dcache.nfs.status.StaleException; import org.dcache.nfs.v4.NfsIdMapping; import org.dcache.nfs.v4.acl.Acls; import org.dcache.nfs.v4.xdr.aceflag4; import org.dcache.nfs.v4.xdr.acemask4; import org.dcache.nfs.v4.xdr.acetype4; import org.dcache.nfs.v4.xdr.nfsace4; import org.dcache.nfs.v4.xdr.uint32_t; import org.dcache.nfs.v4.xdr.utf8str_mixed; import org.dcache.nfs.vfs.AclCheckable; import org.dcache.nfs.vfs.DirectoryEntry; import org.dcache.nfs.vfs.FsStat; import org.dcache.nfs.vfs.Inode; import org.dcache.nfs.vfs.Stat; import org.dcache.nfs.vfs.VirtualFileSystem; import static org.dcache.chimera.FileSystemProvider.StatCacheOption.NO_STAT; import static org.dcache.chimera.FileSystemProvider.StatCacheOption.STAT; import static org.dcache.nfs.v4.xdr.nfs4_prot.*; /** * Interface to a virtual file system. */ public class ChimeraVfs implements VirtualFileSystem, AclCheckable { private static final Logger _log = LoggerFactory.getLogger(ChimeraVfs.class); private final JdbcFs _fs; private final NfsIdMapping _idMapping; public ChimeraVfs(JdbcFs fs, NfsIdMapping idMapping) { _fs = fs; _idMapping = idMapping; } @Override public Inode getRootInode() throws IOException { return toInode(FsInode.getRoot(_fs)); } @Override public Inode lookup(Inode parent, String path) throws IOException { try { FsInode parentFsInode = toFsInode(parent); FsInode fsInode = parentFsInode.inodeOf(path, NO_STAT); return toInode(fsInode); } catch (FileNotFoundHimeraFsException e) { throw new NoEntException("Path Do not exist."); } } @Override public Inode create(Inode parent, Stat.Type type, String path, Subject subject, int mode) throws IOException { int uid = (int) Subjects.getUid(subject); int gid = (int) Subjects.getPrimaryGid(subject); try { FsInode parentFsInode = toFsInode(parent); FsInode fsInode = _fs.createFile(parentFsInode, path, uid, gid, mode | typeToChimera(type), typeToChimera(type)); return toInode(fsInode); } catch (FileExistsChimeraFsException e) { throw new ExistException("path already exists"); } } @Override public Inode mkdir(Inode parent, String path, Subject subject, int mode) throws IOException { int uid = (int) Subjects.getUid(subject); int gid = (int) Subjects.getPrimaryGid(subject); try { FsInode parentFsInode = toFsInode(parent); FsInode fsInode = parentFsInode.mkdir(path, uid, gid, mode); return toInode(fsInode); } catch (FileExistsChimeraFsException e) { throw new ExistException("path already exists"); } } @Override public Inode link(Inode parent, Inode link, String path, Subject subject) throws IOException { FsInode parentFsInode = toFsInode(parent); FsInode linkInode = toFsInode(link); try { FsInode fsInode = _fs.createHLink(parentFsInode, linkInode, path); return toInode(fsInode); } catch (NotDirChimeraException e) { throw new NotDirException("parent not a directory"); } catch (FileExistsChimeraFsException e) { throw new ExistException("path already exists"); } } @Override public Inode symlink(Inode parent, String path, String link, Subject subject, int mode) throws IOException { int uid = (int) Subjects.getUid(subject); int gid = (int) Subjects.getPrimaryGid(subject); try { FsInode parentFsInode = toFsInode(parent); FsInode fsInode = _fs.createLink(parentFsInode, path, uid, gid, mode, link.getBytes(StandardCharsets.UTF_8)); return toInode(fsInode); } catch (FileExistsChimeraFsException e) { throw new ExistException("path already exists"); } } @Override public int read(Inode inode, byte[] data, long offset, int count) throws IOException { FsInode fsInode = toFsInode(inode); return fsInode.read(offset, data, 0, count); } @Override public boolean move(Inode src, String oldName, Inode dest, String newName) throws IOException { FsInode from = toFsInode(src); FsInode to = toFsInode(dest); try { return _fs.rename(_fs.inodeOf(from, oldName, NO_STAT), from, oldName, to, newName); } catch (NotDirChimeraException e) { throw new NotDirException("not a directory"); } catch (FileExistsChimeraFsException e) { throw new ExistException("destination exists"); } catch (DirNotEmptyHimeraFsException e) { throw new NotEmptyException("directory exist and not empty"); } catch (FileNotFoundHimeraFsException e) { throw new NoEntException("file not found"); } } @Override public String readlink(Inode inode) throws IOException { FsInode fsInode = toFsInode(inode); int count = (int) fsInode.statCache().getSize(); byte[] data = new byte[count]; int n = _fs.read(fsInode, 0, data, 0, count); if (n < 0) { throw new NfsIoException("Can't read symlink"); } return new String(data, 0, n, StandardCharsets.UTF_8); } @Override public void remove(Inode parent, String path) throws IOException { FsInode parentFsInode = toFsInode(parent); try { _fs.remove(parentFsInode, path, _fs.inodeOf(parentFsInode, path, STAT)); } catch (FileNotFoundHimeraFsException e) { throw new NoEntException("path not found"); } catch (DirNotEmptyHimeraFsException e) { throw new NotEmptyException("directory not empty"); } } @Override public WriteResult write(Inode inode, byte[] data, long offset, int count, StabilityLevel stabilityLevel) throws IOException { FsInode fsInode = toFsInode(inode); int bytesWritten = fsInode.write(offset, data, 0, count); return new WriteResult(StabilityLevel.FILE_SYNC, bytesWritten); } @Override public void commit(Inode inode, long offset, int count) throws IOException { //nop (all IO is FILE_SYNC so no commits expected) } @Override public List<DirectoryEntry> list(Inode inode) throws IOException { FsInode parentFsInode = toFsInode(inode); List<HimeraDirectoryEntry> list = DirectoryStreamHelper.listOf(parentFsInode); return Lists.transform(list, new ChimeraDirectoryEntryToVfs()); } @Override public Inode parentOf(Inode inode) throws IOException { FsInode parent = toFsInode(inode).getParent(); if (parent == null) { throw new NoEntException("no parent"); } return toInode(parent); } @Override public FsStat getFsStat() throws IOException { org.dcache.chimera.FsStat fsStat = _fs.getFsStat(); return new FsStat(fsStat.getTotalSpace(), fsStat.getTotalFiles(), fsStat.getUsedSpace(), fsStat.getUsedFiles()); } private FsInode toFsInode(Inode inode) throws IOException { return _fs.inodeFromBytes(inode.getFileId()); } private Inode toInode(final FsInode inode) { try { return Inode.forFile(_fs.inodeToBytes(inode)); } catch (ChimeraFsException e) { throw new RuntimeException("bug found", e); } } @Override public Stat getattr(Inode inode) throws IOException { FsInode fsInode = toFsInode(inode); try { return fromChimeraStat(fsInode.stat(), fsInode.ino()); } catch (FileNotFoundHimeraFsException e) { throw new NoEntException("Path Do not exist."); } } @Override public void setattr(Inode inode, Stat stat) throws IOException { FsInode fsInode = toFsInode(inode); try { fsInode.setStat(toChimeraStat(stat)); } catch (InvalidArgumentChimeraException e) { throw new InvalException(e.getMessage()); } catch (IsDirChimeraException e) { throw new IsDirException(e.getMessage()); } catch (FileNotFoundHimeraFsException e) { throw new StaleException(e.getMessage()); } } @Override public nfsace4[] getAcl(Inode inode) throws IOException { FsInode fsInode = toFsInode(inode); try { nfsace4[] aces; List<ACE> dacl = _fs.getACL(fsInode); org.dcache.chimera.posix.Stat stat = fsInode.statCache(); nfsace4[] unixAcl = Acls.of(stat.getMode(), fsInode.isDirectory()); aces = new nfsace4[dacl.size() + unixAcl.length]; int i = 0; for (ACE ace : dacl) { aces[i] = valueOf(ace, _idMapping); i++; } System.arraycopy(unixAcl, 0, aces, i, unixAcl.length); return Acls.compact(aces); } catch (FileNotFoundHimeraFsException e) { throw new StaleException(e.getMessage()); } } @Override public void setAcl(Inode inode, nfsace4[] acl) throws IOException { FsInode fsInode = toFsInode(inode); List<ACE> dacl = new ArrayList<>(); for (nfsace4 ace : acl) { dacl.add(valueOf(ace, _idMapping)); } try { _fs.setACL(fsInode, dacl); } catch (FileNotFoundHimeraFsException e) { throw new StaleException(e.getMessage()); } } private static Stat fromChimeraStat(org.dcache.chimera.posix.Stat pStat, long fileid) { Stat stat = new Stat(); stat.setATime(pStat.getATime()); stat.setCTime(pStat.getCTime()); stat.setMTime(pStat.getMTime()); stat.setGid(pStat.getGid()); stat.setUid(pStat.getUid()); stat.setDev(pStat.getDev()); stat.setIno(Longs.hashCode(pStat.getIno())); stat.setMode(pStat.getMode()); stat.setNlink(pStat.getNlink()); stat.setRdev(pStat.getRdev()); stat.setSize(pStat.getSize()); stat.setFileid(fileid); stat.setGeneration(pStat.getGeneration()); return stat; } private static org.dcache.chimera.posix.Stat toChimeraStat(Stat stat) { org.dcache.chimera.posix.Stat pStat = new org.dcache.chimera.posix.Stat(); if (stat.isDefined(Stat.StatAttribute.ATIME)) { pStat.setATime(stat.getATime()); } if (stat.isDefined(Stat.StatAttribute.CTIME)) { pStat.setCTime(stat.getCTime()); } if (stat.isDefined(Stat.StatAttribute.MTIME)) { pStat.setMTime(stat.getMTime()); } if (stat.isDefined(Stat.StatAttribute.GROUP)) { pStat.setGid(stat.getGid()); } if (stat.isDefined(Stat.StatAttribute.OWNER)) { pStat.setUid(stat.getUid()); } if (stat.isDefined(Stat.StatAttribute.DEV)) { pStat.setDev(stat.getDev()); } if (stat.isDefined(Stat.StatAttribute.MODE)) { pStat.setMode(stat.getMode()); } if (stat.isDefined(Stat.StatAttribute.NLINK)) { pStat.setNlink(stat.getNlink()); } if (stat.isDefined(Stat.StatAttribute.RDEV)) { pStat.setRdev(stat.getRdev()); } if (stat.isDefined(Stat.StatAttribute.SIZE)) { pStat.setSize(stat.getSize()); } if (stat.isDefined(Stat.StatAttribute.GENERATION)) { pStat.setGeneration(stat.getGeneration()); } return pStat; } @Override public int access(Inode inode, int mode) throws IOException { int accessmask = mode; if ((mode & (ACCESS4_MODIFY | ACCESS4_EXTEND)) != 0) { FsInode fsInode = toFsInode(inode); if (shouldRejectUpdates(fsInode)) { accessmask ^= (ACCESS4_MODIFY | ACCESS4_EXTEND); } } return accessmask; } private boolean shouldRejectUpdates(FsInode fsInode) throws ChimeraFsException { return fsInode.type() == FsInodeType.INODE && fsInode.getLevel() == 0 && !fsInode.isDirectory() && (!_fs.getInodeLocations(fsInode, StorageGenericLocation.TAPE).isEmpty() || !_fs.getInodeLocations(fsInode, StorageGenericLocation.DISK).isEmpty()); } @Override public boolean hasIOLayout(Inode inode) throws IOException { FsInode fsInode = toFsInode(inode); return fsInode.type() == FsInodeType.INODE && fsInode.getLevel() == 0; } @Override public AclCheckable getAclCheckable() { return this; } @Override public NfsIdMapping getIdMapper() { return _idMapping; } private class ChimeraDirectoryEntryToVfs implements Function<HimeraDirectoryEntry, DirectoryEntry> { @Override public DirectoryEntry apply(HimeraDirectoryEntry e) { return new DirectoryEntry(e.getName(), toInode(e.getInode()), fromChimeraStat(e.getStat(), e.getInode().ino())); } } private int typeToChimera(Stat.Type type) { switch (type) { case SYMLINK: return Stat.S_IFLNK; case DIRECTORY: return Stat.S_IFDIR; case SOCK: return Stat.S_IFSOCK; case FIFO: return Stat.S_IFIFO; case BLOCK: return Stat.S_IFBLK; case CHAR: return Stat.S_IFCHR; case REGULAR: default: return Stat.S_IFREG; } } private static nfsace4 valueOf(ACE ace, NfsIdMapping idMapping) { String principal; switch (ace.getWho()) { case USER: principal = idMapping.uidToPrincipal(ace.getWhoID()); break; case GROUP: principal = idMapping.gidToPrincipal(ace.getWhoID()); break; default: principal = ace.getWho().getAbbreviation(); } nfsace4 nfsace = new nfsace4(); nfsace.access_mask = new acemask4(new uint32_t(ace.getAccessMsk())); nfsace.flag = new aceflag4(new uint32_t(ace.getFlags())); nfsace.type = new acetype4(new uint32_t(ace.getType().getValue())); nfsace.who = new utf8str_mixed(principal); return nfsace; } private static ACE valueOf(nfsace4 ace, NfsIdMapping idMapping) throws BadOwnerException { String principal = ace.who.toString(); int type = ace.type.value.value; int flags = ace.flag.value.value; int mask = ace.access_mask.value.value; int id = -1; Who who = Who.fromAbbreviation(principal); if (who == null) { // not a special pricipal boolean isGroup = AceFlags.IDENTIFIER_GROUP.matches(flags); if (isGroup) { who = Who.GROUP; id = idMapping.principalToGid(principal); } else { who = Who.USER; id = idMapping.principalToUid(principal); } } return new ACE(AceType.valueOf(type), flags, mask, who, id); } @Override public Access checkAcl(Subject subject, Inode inode, int access) throws IOException { FsInode fsInode = toFsInode(inode); List<ACE> acl = _fs.getACL(fsInode); org.dcache.chimera.posix.Stat stat = _fs.stat(fsInode); return checkAcl(subject, acl, stat.getUid(), stat.getGid(), access); } private Access checkAcl(Subject subject, List<ACE> acl, int owner, int group, int access) { for (ACE ace : acl) { int flag = ace.getFlags(); if ((flag & ACE4_INHERIT_ONLY_ACE) != 0) { continue; } if ((ace.getType() != AceType.ACCESS_ALLOWED_ACE_TYPE) && (ace.getType() != AceType.ACCESS_DENIED_ACE_TYPE)) { continue; } int ace_mask = ace.getAccessMsk(); if ((ace_mask & access) == 0) { continue; } Who who = ace.getWho(); if ((who == Who.EVERYONE) || (who == Who.OWNER && Subjects.hasUid(subject, owner)) || (who == Who.OWNER_GROUP && Subjects.hasGid(subject, group)) || (who == Who.GROUP && Subjects.hasGid(subject, ace.getWhoID())) || (who == Who.USER && Subjects.hasUid(subject, ace.getWhoID()))) { if (ace.getType() == AceType.ACCESS_DENIED_ACE_TYPE) { return Access.DENY; } else { return Access.ALLOW; } } } return Access.UNDEFINED; } }