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-rw-r--r--pkg/lisafs/handlers.go650
1 files changed, 647 insertions, 3 deletions
diff --git a/pkg/lisafs/handlers.go b/pkg/lisafs/handlers.go
index 9b8d8164a..82807734d 100644
--- a/pkg/lisafs/handlers.go
+++ b/pkg/lisafs/handlers.go
@@ -15,15 +15,23 @@
package lisafs
import (
+ "fmt"
"path"
"path/filepath"
+ "strings"
"golang.org/x/sys/unix"
"gvisor.dev/gvisor/pkg/flipcall"
+ "gvisor.dev/gvisor/pkg/fspath"
"gvisor.dev/gvisor/pkg/log"
"gvisor.dev/gvisor/pkg/marshal/primitive"
)
+const (
+ allowedOpenFlags = unix.O_ACCMODE | unix.O_TRUNC
+ setStatSupportedMask = unix.STATX_MODE | unix.STATX_UID | unix.STATX_GID | unix.STATX_SIZE | unix.STATX_ATIME | unix.STATX_MTIME
+)
+
// RPCHandler defines a handler that is invoked when the associated message is
// received. The handler is responsible for:
//
@@ -34,9 +42,35 @@ import (
type RPCHandler func(c *Connection, comm Communicator, payloadLen uint32) (uint32, error)
var handlers = [...]RPCHandler{
- Error: ErrorHandler,
- Mount: MountHandler,
- Channel: ChannelHandler,
+ Error: ErrorHandler,
+ Mount: MountHandler,
+ Channel: ChannelHandler,
+ FStat: FStatHandler,
+ SetStat: SetStatHandler,
+ Walk: WalkHandler,
+ WalkStat: WalkStatHandler,
+ OpenAt: OpenAtHandler,
+ OpenCreateAt: OpenCreateAtHandler,
+ Close: CloseHandler,
+ FSync: FSyncHandler,
+ PWrite: PWriteHandler,
+ PRead: PReadHandler,
+ MkdirAt: MkdirAtHandler,
+ MknodAt: MknodAtHandler,
+ SymlinkAt: SymlinkAtHandler,
+ LinkAt: LinkAtHandler,
+ FStatFS: FStatFSHandler,
+ FAllocate: FAllocateHandler,
+ ReadLinkAt: ReadLinkAtHandler,
+ Flush: FlushHandler,
+ Connect: ConnectHandler,
+ UnlinkAt: UnlinkAtHandler,
+ RenameAt: RenameAtHandler,
+ Getdents64: Getdents64Handler,
+ FGetXattr: FGetXattrHandler,
+ FSetXattr: FSetXattrHandler,
+ FListXattr: FListXattrHandler,
+ FRemoveXattr: FRemoveXattrHandler,
}
// ErrorHandler handles Error message.
@@ -122,3 +156,613 @@ func ChannelHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32
resp.MarshalUnsafe(comm.PayloadBuf(respLen))
return respLen, nil
}
+
+// FStatHandler handles the FStat RPC.
+func FStatHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req StatReq
+ req.UnmarshalUnsafe(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.lookupFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+
+ switch t := fd.(type) {
+ case *ControlFD:
+ return t.impl.Stat(c, comm)
+ case *OpenFD:
+ return t.impl.Stat(c, comm)
+ default:
+ panic(fmt.Sprintf("unknown fd type %T", t))
+ }
+}
+
+// SetStatHandler handles the SetStat RPC.
+func SetStatHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+
+ var req SetStatReq
+ req.UnmarshalUnsafe(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupControlFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+
+ if req.Mask&^setStatSupportedMask != 0 {
+ return 0, unix.EPERM
+ }
+
+ return fd.impl.SetStat(c, comm, req)
+}
+
+// WalkHandler handles the Walk RPC.
+func WalkHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req WalkReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupControlFD(req.DirFD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.IsDir() {
+ return 0, unix.ENOTDIR
+ }
+ for _, name := range req.Path {
+ if err := checkSafeName(name); err != nil {
+ return 0, err
+ }
+ }
+
+ return fd.impl.Walk(c, comm, req.Path)
+}
+
+// WalkStatHandler handles the WalkStat RPC.
+func WalkStatHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req WalkReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupControlFD(req.DirFD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+
+ // Note that this fd is allowed to not actually be a directory when the
+ // only path component to walk is "" (self).
+ if !fd.IsDir() {
+ if len(req.Path) > 1 || (len(req.Path) == 1 && len(req.Path[0]) > 0) {
+ return 0, unix.ENOTDIR
+ }
+ }
+ for i, name := range req.Path {
+ // First component is allowed to be "".
+ if i == 0 && len(name) == 0 {
+ continue
+ }
+ if err := checkSafeName(name); err != nil {
+ return 0, err
+ }
+ }
+
+ return fd.impl.WalkStat(c, comm, req.Path)
+}
+
+// OpenAtHandler handles the OpenAt RPC.
+func OpenAtHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req OpenAtReq
+ req.UnmarshalUnsafe(comm.PayloadBuf(payloadLen))
+
+ // Only keep allowed open flags.
+ if allowedFlags := req.Flags & allowedOpenFlags; allowedFlags != req.Flags {
+ log.Debugf("discarding open flags that are not allowed: old open flags = %d, new open flags = %d", req.Flags, allowedFlags)
+ req.Flags = allowedFlags
+ }
+
+ accessMode := req.Flags & unix.O_ACCMODE
+ trunc := req.Flags&unix.O_TRUNC != 0
+ if c.readonly && (accessMode != unix.O_RDONLY || trunc) {
+ return 0, unix.EROFS
+ }
+
+ fd, err := c.LookupControlFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if fd.IsDir() {
+ // Directory is not truncatable and must be opened with O_RDONLY.
+ if accessMode != unix.O_RDONLY || trunc {
+ return 0, unix.EISDIR
+ }
+ }
+
+ return fd.impl.Open(c, comm, req.Flags)
+}
+
+// OpenCreateAtHandler handles the OpenCreateAt RPC.
+func OpenCreateAtHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+ var req OpenCreateAtReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ // Only keep allowed open flags.
+ if allowedFlags := req.Flags & allowedOpenFlags; allowedFlags != req.Flags {
+ log.Debugf("discarding open flags that are not allowed: old open flags = %d, new open flags = %d", req.Flags, allowedFlags)
+ req.Flags = allowedFlags
+ }
+
+ name := string(req.Name)
+ if err := checkSafeName(name); err != nil {
+ return 0, err
+ }
+
+ fd, err := c.LookupControlFD(req.DirFD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.IsDir() {
+ return 0, unix.ENOTDIR
+ }
+
+ return fd.impl.OpenCreate(c, comm, req.Mode, req.UID, req.GID, name, uint32(req.Flags))
+}
+
+// CloseHandler handles the Close RPC.
+func CloseHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req CloseReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+ for _, fd := range req.FDs {
+ c.RemoveFD(fd)
+ }
+
+ // There is no response message for this.
+ return 0, nil
+}
+
+// FSyncHandler handles the FSync RPC.
+func FSyncHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req FsyncReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ // Return the first error we encounter, but sync everything we can
+ // regardless.
+ var retErr error
+ for _, fdid := range req.FDs {
+ if err := c.fsyncFD(fdid); err != nil && retErr == nil {
+ retErr = err
+ }
+ }
+
+ // There is no response message for this.
+ return 0, retErr
+}
+
+func (c *Connection) fsyncFD(id FDID) error {
+ fd, err := c.LookupOpenFD(id)
+ if err != nil {
+ return err
+ }
+ return fd.impl.Sync(c)
+}
+
+// PWriteHandler handles the PWrite RPC.
+func PWriteHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+ var req PWriteReq
+ // Note that it is an optimized Unmarshal operation which avoids any buffer
+ // allocation and copying. req.Buf just points to payload. This is safe to do
+ // as the handler owns payload and req's lifetime is limited to the handler.
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+ fd, err := c.LookupOpenFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ if !fd.writable {
+ return 0, unix.EBADF
+ }
+ return fd.impl.Write(c, comm, req.Buf, uint64(req.Offset))
+}
+
+// PReadHandler handles the PRead RPC.
+func PReadHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req PReadReq
+ req.UnmarshalUnsafe(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupOpenFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.readable {
+ return 0, unix.EBADF
+ }
+ return fd.impl.Read(c, comm, req.Offset, req.Count)
+}
+
+// MkdirAtHandler handles the MkdirAt RPC.
+func MkdirAtHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+ var req MkdirAtReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ name := string(req.Name)
+ if err := checkSafeName(name); err != nil {
+ return 0, err
+ }
+
+ fd, err := c.LookupControlFD(req.DirFD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.IsDir() {
+ return 0, unix.ENOTDIR
+ }
+ return fd.impl.Mkdir(c, comm, req.Mode, req.UID, req.GID, name)
+}
+
+// MknodAtHandler handles the MknodAt RPC.
+func MknodAtHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+ var req MknodAtReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ name := string(req.Name)
+ if err := checkSafeName(name); err != nil {
+ return 0, err
+ }
+
+ fd, err := c.LookupControlFD(req.DirFD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.IsDir() {
+ return 0, unix.ENOTDIR
+ }
+ return fd.impl.Mknod(c, comm, req.Mode, req.UID, req.GID, name, uint32(req.Minor), uint32(req.Major))
+}
+
+// SymlinkAtHandler handles the SymlinkAt RPC.
+func SymlinkAtHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+ var req SymlinkAtReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ name := string(req.Name)
+ if err := checkSafeName(name); err != nil {
+ return 0, err
+ }
+
+ fd, err := c.LookupControlFD(req.DirFD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.IsDir() {
+ return 0, unix.ENOTDIR
+ }
+ return fd.impl.Symlink(c, comm, name, string(req.Target), req.UID, req.GID)
+}
+
+// LinkAtHandler handles the LinkAt RPC.
+func LinkAtHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+ var req LinkAtReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ name := string(req.Name)
+ if err := checkSafeName(name); err != nil {
+ return 0, err
+ }
+
+ fd, err := c.LookupControlFD(req.DirFD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.IsDir() {
+ return 0, unix.ENOTDIR
+ }
+
+ targetFD, err := c.LookupControlFD(req.Target)
+ if err != nil {
+ return 0, err
+ }
+ return targetFD.impl.Link(c, comm, fd.impl, name)
+}
+
+// FStatFSHandler handles the FStatFS RPC.
+func FStatFSHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req FStatFSReq
+ req.UnmarshalUnsafe(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupControlFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ return fd.impl.StatFS(c, comm)
+}
+
+// FAllocateHandler handles the FAllocate RPC.
+func FAllocateHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+ var req FAllocateReq
+ req.UnmarshalUnsafe(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupOpenFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.writable {
+ return 0, unix.EBADF
+ }
+ return 0, fd.impl.Allocate(c, req.Mode, req.Offset, req.Length)
+}
+
+// ReadLinkAtHandler handles the ReadLinkAt RPC.
+func ReadLinkAtHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req ReadLinkAtReq
+ req.UnmarshalUnsafe(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupControlFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.IsSymlink() {
+ return 0, unix.EINVAL
+ }
+ return fd.impl.Readlink(c, comm)
+}
+
+// FlushHandler handles the Flush RPC.
+func FlushHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req FlushReq
+ req.UnmarshalUnsafe(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupOpenFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+
+ return 0, fd.impl.Flush(c)
+}
+
+// ConnectHandler handles the Connect RPC.
+func ConnectHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req ConnectReq
+ req.UnmarshalUnsafe(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupControlFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.IsSocket() {
+ return 0, unix.ENOTSOCK
+ }
+ return 0, fd.impl.Connect(c, comm, req.SockType)
+}
+
+// UnlinkAtHandler handles the UnlinkAt RPC.
+func UnlinkAtHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+ var req UnlinkAtReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ name := string(req.Name)
+ if err := checkSafeName(name); err != nil {
+ return 0, err
+ }
+
+ fd, err := c.LookupControlFD(req.DirFD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.IsDir() {
+ return 0, unix.ENOTDIR
+ }
+ return 0, fd.impl.Unlink(c, name, uint32(req.Flags))
+}
+
+// RenameAtHandler handles the RenameAt RPC.
+func RenameAtHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+ var req RenameAtReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ newName := string(req.NewName)
+ if err := checkSafeName(newName); err != nil {
+ return 0, err
+ }
+
+ renamed, err := c.LookupControlFD(req.Renamed)
+ if err != nil {
+ return 0, err
+ }
+ defer renamed.DecRef(nil)
+
+ newDir, err := c.LookupControlFD(req.NewDir)
+ if err != nil {
+ return 0, err
+ }
+ defer newDir.DecRef(nil)
+ if !newDir.IsDir() {
+ return 0, unix.ENOTDIR
+ }
+
+ // Hold RenameMu for writing during rename, this is important.
+ c.server.RenameMu.Lock()
+ defer c.server.RenameMu.Unlock()
+
+ if renamed.parent == nil {
+ // renamed is root.
+ return 0, unix.EBUSY
+ }
+
+ oldParentPath := renamed.parent.FilePathLocked()
+ oldPath := oldParentPath + "/" + renamed.name
+ if newName == renamed.name && oldParentPath == newDir.FilePathLocked() {
+ // Nothing to do.
+ return 0, nil
+ }
+
+ updateControlFD, cleanUp, err := renamed.impl.RenameLocked(c, newDir.impl, newName)
+ if err != nil {
+ return 0, err
+ }
+
+ c.server.forEachMountPoint(func(root *ControlFD) {
+ if !strings.HasPrefix(oldPath, root.name) {
+ return
+ }
+ pit := fspath.Parse(oldPath[len(root.name):]).Begin
+ root.renameRecursiveLocked(newDir, newName, pit, updateControlFD)
+ })
+
+ if cleanUp != nil {
+ cleanUp()
+ }
+ return 0, nil
+}
+
+// Precondition: rename mutex must be locked for writing.
+func (fd *ControlFD) renameRecursiveLocked(newDir *ControlFD, newName string, pit fspath.Iterator, updateControlFD func(ControlFDImpl)) {
+ if !pit.Ok() {
+ // fd should be renamed.
+ fd.clearParentLocked()
+ fd.setParentLocked(newDir)
+ fd.name = newName
+ if updateControlFD != nil {
+ updateControlFD(fd.impl)
+ }
+ return
+ }
+
+ cur := pit.String()
+ next := pit.Next()
+ // No need to hold fd.childrenMu because RenameMu is locked for writing.
+ for child := fd.children.Front(); child != nil; child = child.Next() {
+ if child.name == cur {
+ child.renameRecursiveLocked(newDir, newName, next, updateControlFD)
+ }
+ }
+}
+
+// Getdents64Handler handles the Getdents64 RPC.
+func Getdents64Handler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req Getdents64Req
+ req.UnmarshalUnsafe(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupOpenFD(req.DirFD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ if !fd.controlFD.IsDir() {
+ return 0, unix.ENOTDIR
+ }
+
+ seek0 := false
+ if req.Count < 0 {
+ seek0 = true
+ req.Count = -req.Count
+ }
+ return fd.impl.Getdent64(c, comm, uint32(req.Count), seek0)
+}
+
+// FGetXattrHandler handles the FGetXattr RPC.
+func FGetXattrHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req FGetXattrReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupControlFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ return fd.impl.GetXattr(c, comm, string(req.Name), uint32(req.BufSize))
+}
+
+// FSetXattrHandler handles the FSetXattr RPC.
+func FSetXattrHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+ var req FSetXattrReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupControlFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ return 0, fd.impl.SetXattr(c, string(req.Name), string(req.Value), uint32(req.Flags))
+}
+
+// FListXattrHandler handles the FListXattr RPC.
+func FListXattrHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ var req FListXattrReq
+ req.UnmarshalUnsafe(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupControlFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ return fd.impl.ListXattr(c, comm, req.Size)
+}
+
+// FRemoveXattrHandler handles the FRemoveXattr RPC.
+func FRemoveXattrHandler(c *Connection, comm Communicator, payloadLen uint32) (uint32, error) {
+ if c.readonly {
+ return 0, unix.EROFS
+ }
+ var req FRemoveXattrReq
+ req.UnmarshalBytes(comm.PayloadBuf(payloadLen))
+
+ fd, err := c.LookupControlFD(req.FD)
+ if err != nil {
+ return 0, err
+ }
+ defer fd.DecRef(nil)
+ return 0, fd.impl.RemoveXattr(c, comm, string(req.Name))
+}
+
+// checkSafeName validates the name and returns nil or returns an error.
+func checkSafeName(name string) error {
+ if name != "" && !strings.Contains(name, "/") && name != "." && name != ".." {
+ return nil
+ }
+ return unix.EINVAL
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 06:29:20 +0000