Fallback parsing for Content-Disposition minefield (#1144)

This commit is contained in:
Neil Alexander 2020-06-17 14:26:45 +01:00 committed by GitHub
parent 38053a5bb7
commit 23bed196e6
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
2 changed files with 24 additions and 5 deletions

View file

@ -47,6 +47,10 @@ const mediaIDCharacters = "A-Za-z0-9_=-"
// Note: unfortunately regex.MustCompile() cannot be assigned to a const
var mediaIDRegex = regexp.MustCompile("^[" + mediaIDCharacters + "]+$")
// Regular expressions to help us cope with Content-Disposition parsing
var rfc2183 = regexp.MustCompile(`filename\=utf-8\"(.*)\"`)
var rfc6266 = regexp.MustCompile(`filename\*\=utf-8\'\'(.*)`)
// downloadRequest metadata included in or derivable from a download or thumbnail request
// https://matrix.org/docs/spec/client_server/r0.2.0.html#get-matrix-media-r0-download-servername-mediaid
// http://matrix.org/docs/spec/client_server/r0.2.0.html#get-matrix-media-r0-thumbnail-servername-mediaid
@ -378,8 +382,8 @@ func (r *downloadRequest) addDownloadFilenameToHeaders(
} else {
// For UTF-8 filenames, we quote always, as that's the standard
w.Header().Set("Content-Disposition", fmt.Sprintf(
`inline; filename=utf-8"%s"`,
unescaped,
`inline; filename*=utf-8''%s`,
url.QueryEscape(unescaped),
))
}
@ -700,9 +704,22 @@ func (r *downloadRequest) fetchRemoteFile(
}
r.MediaMetadata.FileSizeBytes = types.FileSizeBytes(contentLength)
r.MediaMetadata.ContentType = types.ContentType(resp.Header.Get("Content-Type"))
_, params, err := mime.ParseMediaType(resp.Header.Get("Content-Disposition"))
if err == nil && params["filename"] != "" {
dispositionHeader := resp.Header.Get("Content-Disposition")
if _, params, e := mime.ParseMediaType(dispositionHeader); e == nil {
if params["filename"] != "" {
r.MediaMetadata.UploadName = types.Filename(params["filename"])
} else if params["filename*"] != "" {
r.MediaMetadata.UploadName = types.Filename(params["filename*"])
}
} else {
if matches := rfc6266.FindStringSubmatch(dispositionHeader); len(matches) > 1 {
// Always prefer the RFC6266 UTF-8 name if possible
r.MediaMetadata.UploadName = types.Filename(matches[1])
} else if matches := rfc2183.FindStringSubmatch(dispositionHeader); len(matches) > 1 {
// Otherwise, see if an RFC2183 name was provided (ASCII only)
r.MediaMetadata.UploadName = types.Filename(matches[1])
}
}
r.Logger.Info("Transferring remote file")

View file

@ -331,4 +331,6 @@ Can download file 'ascii'
Can download file 'name with spaces'
Can download file 'name;with;semicolons'
Can download specifying a different ASCII file name
Can download with Unicode file name over federation
Can download specifying a different Unicode file name
Inbound /v1/send_join rejects joins from other servers