From e85b1cecb7a8737e1b0a0e25bfcb31af7d964d56 Mon Sep 17 00:00:00 2001
From: Matthew Penner <me@matthewp.io>
Date: Fri, 31 Jul 2020 16:01:32 -0600
Subject: [PATCH] Fix 500 errors on file routes when accessing a file that
 doesn't exist

---
 router/router_server_files.go  | 29 +++++++++++++++++++++++++++--
 server/filesystem.go           |  8 ++++----
 server/filesystem_unarchive.go |  5 +++++
 3 files changed, 36 insertions(+), 6 deletions(-)

diff --git a/router/router_server_files.go b/router/router_server_files.go
index 4559e0c..da3d996 100644
--- a/router/router_server_files.go
+++ b/router/router_server_files.go
@@ -3,6 +3,7 @@ package router
 import (
 	"bufio"
 	"context"
+	"errors"
 	"github.com/gin-gonic/gin"
 	"github.com/pterodactyl/wings/server"
 	"golang.org/x/sync/errgroup"
@@ -129,7 +130,17 @@ func putServerRenameFiles(c *gin.Context) {
 			case <-ctx.Done():
 				return ctx.Err()
 			default:
-				return s.Filesystem.Rename(pf, pt)
+				if err := s.Filesystem.Rename(pf, pt); err != nil {
+					// Return nil if the error is an is not exists.
+					// NOTE: os.IsNotExist() does not work if the error is wrapped.
+					if errors.Is(err, os.ErrNotExist) {
+						return nil
+					}
+
+					return err
+				}
+
+				return nil
 			}
 		})
 	}
@@ -155,6 +166,13 @@ func postServerCopyFile(c *gin.Context) {
 	}
 
 	if err := s.Filesystem.Copy(data.Location); err != nil {
+		// Check if the file does not exist.
+		// NOTE: os.IsNotExist() does not work if the error is wrapped.
+		if errors.Is(err, os.ErrNotExist) {
+			c.Status(http.StatusNotFound)
+			return
+		}
+
 		TrackedServerError(err, s).AbortWithServerError(c)
 		return
 	}
@@ -177,7 +195,7 @@ func postServerDeleteFiles(c *gin.Context) {
 
 	if len(data.Files) == 0 {
 		c.AbortWithStatusJSON(http.StatusUnprocessableEntity, gin.H{
-			"error": "No files were specififed for deletion.",
+			"error": "No files were specified for deletion.",
 		})
 		return
 	}
@@ -311,6 +329,13 @@ func postServerDecompressFiles(c *gin.Context) {
 	}
 
 	if err := s.Filesystem.DecompressFile(data.RootPath, data.File); err != nil {
+		// Check if the file does not exist.
+		// NOTE: os.IsNotExist() does not work if the error is wrapped.
+		if errors.Is(err, os.ErrNotExist) {
+			c.Status(http.StatusNotFound)
+			return
+		}
+
 		TrackedServerError(err, s).AbortWithServerError(c)
 		return
 	}
diff --git a/server/filesystem.go b/server/filesystem.go
index 4c1ea69..4f26684 100644
--- a/server/filesystem.go
+++ b/server/filesystem.go
@@ -40,8 +40,8 @@ func IsPathResolutionError(err error) bool {
 }
 
 type Filesystem struct {
-	Server        *Server
-	cacheDiskMu   sync.Mutex
+	Server      *Server
+	cacheDiskMu sync.Mutex
 }
 
 // Returns the root path that contains all of a server's data.
@@ -424,7 +424,7 @@ func (fs *Filesystem) unsafeStat(p string) (*Stat, error) {
 	return st, nil
 }
 
-// Creates a new directory (name) at a specificied path (p) for the server.
+// Creates a new directory (name) at a specified path (p) for the server.
 func (fs *Filesystem) CreateDirectory(name string, p string) error {
 	cleaned, err := fs.SafePath(path.Join(p, name))
 	if err != nil {
@@ -540,7 +540,7 @@ func (fs *Filesystem) Copy(p string) error {
 	}
 
 	if s, err := os.Stat(cleaned); err != nil {
-		return err
+		return errors.WithStack(err)
 	} else if s.IsDir() || !s.Mode().IsRegular() {
 		// If this is a directory or not a regular file, just throw a not-exist error
 		// since anything calling this function should understand what that means.
diff --git a/server/filesystem_unarchive.go b/server/filesystem_unarchive.go
index 9e40c28..bea2c76 100644
--- a/server/filesystem_unarchive.go
+++ b/server/filesystem_unarchive.go
@@ -73,6 +73,11 @@ func (fs *Filesystem) DecompressFile(dir string, file string) error {
 		return errors.WithStack(err)
 	}
 
+	// Make sure the file exists basically.
+	if _, err := os.Stat(source); err != nil {
+		return errors.WithStack(err)
+	}
+
 	// Walk over all of the files spinning up an additional go-routine for each file we've encountered
 	// and then extract that file from the archive and write it to the disk. If any part of this process
 	// encounters an error the entire process will be stopped.