diff options
Diffstat (limited to 'weed/sftpd/sftp_server.go')
| -rw-r--r-- | weed/sftpd/sftp_server.go | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/weed/sftpd/sftp_server.go b/weed/sftpd/sftp_server.go index f158aeb64..e53098e6b 100644 --- a/weed/sftpd/sftp_server.go +++ b/weed/sftpd/sftp_server.go @@ -6,6 +6,8 @@ import ( "fmt" "io" "os" + "path" + "strings" "time" "github.com/pkg/sftp" @@ -37,6 +39,28 @@ func NewSftpServer(filerAddr pb.ServerAddress, grpcDialOption grpc.DialOption, d } } +// toAbsolutePath translates a user-relative path to an absolute filer path. +// When a user has HomeDir="/sftp/user", their view of "/" maps to "/sftp/user". +// This implements chroot-like behavior where the user's home directory +// becomes their root. +func (fs *SftpServer) toAbsolutePath(userPath string) (string, error) { + // If user has root as home directory, no translation needed + if fs.user.HomeDir == "" || fs.user.HomeDir == "/" { + return path.Clean(userPath), nil + } + + // Concatenate home directory with user path, then clean to resolve any ".." components + p := path.Join(fs.user.HomeDir, strings.TrimPrefix(userPath, "/")) + + // Security check: ensure the final path is within the home directory. + // This prevents path traversal attacks like `../..` that could escape the chroot jail. + if !strings.HasPrefix(p, fs.user.HomeDir+"/") && p != fs.user.HomeDir { + return "", fmt.Errorf("path traversal attempt: %s resolves to %s which is outside home dir %s", userPath, p, fs.user.HomeDir) + } + + return p, nil +} + // Fileread is invoked for “get” requests. func (fs *SftpServer) Fileread(req *sftp.Request) (io.ReaderAt, error) { return fs.readFile(req) |