Merge pull request #1079 from hedgedoc/fix/mimeTypes

1 files changed, 17 insertions, 2 deletions

diff --git a/lib/web/imageRouter/index.js b/lib/web/imageRouter/index.js
index 0a72c65c..ee123867 100644
--- a/lib/web/imageRouter/index.js
+++ b/lib/web/imageRouter/index.js
@@ -7,6 +7,7 @@ const FileType = require('file-type')
 const fs = require('fs')
 const os = require('os')
 const rimraf = require('rimraf')
+const isSvg = require('is-svg')
 
 const config = require('../../config')
 const logger = require('../../logger')
@@ -15,12 +16,26 @@ const errors = require('../../errors')
 const imageRouter = (module.exports = Router())
 
 async function checkUploadType (filePath) {
-  const typeFromMagic = await FileType.fromFile(filePath)
+  const extension = path.extname(filePath).toLowerCase()
+  let typeFromMagic = await FileType.fromFile(filePath)
+  if (extension === '.svg' && (typeFromMagic === undefined || typeFromMagic.mime === 'application/xml')) {
+    const fileContent = fs.readFileSync(filePath)
+    if (isSvg(fileContent)) {
+      typeFromMagic = {
+        ext: 'svg',
+        mime: 'image/svg+xml'
+      }
+    }
+  }
   if (typeFromMagic === undefined) {
     logger.error('Image upload error: Could not determine MIME-type')
     return false
   }
-  if (path.extname(filePath) !== '.' + typeFromMagic.ext) {
+  // .jpeg, .jfif, .jpe files are identified by FileType to have the extension jpg
+  if (['.jpeg', '.jfif', '.jpe'].includes(extension) && typeFromMagic.ext === 'jpg') {
+    typeFromMagic.ext = extension.substr(1)
+  }
+  if (extension !== '.' + typeFromMagic.ext) {
     logger.error(
       'Image upload error: Provided file extension does not match MIME-type'
     )