From 260b148b920df030331b007d057fdfa35fa12839 Mon Sep 17 00:00:00 2001 From: eal Date: Sat, 11 Nov 2017 23:09:33 +0200 Subject: [PATCH] Use headers for file content type recognition. --- lib/pleroma/upload.ex | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) diff --git a/lib/pleroma/upload.ex b/lib/pleroma/upload.ex index d5723f5de..ce6e23bae 100644 --- a/lib/pleroma/upload.ex +++ b/lib/pleroma/upload.ex @@ -9,9 +9,8 @@ def store(%Plug.Upload{} = file) do File.cp!(file.path, result_file) # fix content type on some image uploads - matches = Regex.named_captures(~r/\.(?(jpg|jpeg|png|gif))$/i, file.filename) - content_type = if file.content_type == "application/octet-stream" and matches do - if matches["ext"] == "jpg", do: "image/jpeg", else: "image/#{matches["ext"]}" + content_type = if file.content_type == "application/octet-stream" do + get_content_type(file.path) else file.content_type end @@ -61,4 +60,30 @@ defp upload_path do defp url_for(file) do "#{Web.base_url()}/media/#{file}" end + + def get_content_type(file) do + # PNG: 89 50 4E 47 0D 0A 1A 0A + # GIF: 47 49 46 38 37 61 + # GIF: 47 49 46 38 39 61 + # JPEG: FF D8 FF DB + # JPEG: FF D8 FF E0 ?? ?? 4A 46 49 46 00 01 + # JPEG: FF D8 FF E1 ?? ?? 45 78 69 66 00 00 + match = File.open(file, [:read], fn(f) -> + case IO.binread(f, 8) do + <<0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a>> -> + "image/png" + <<0x47, 0x49, 0x46, 0x38, _, 0x61, _, _>> -> + "image/gif" + <<0xff, 0xd8, 0xff, _, _, _, _, _>> -> + "image/jpeg" + _ -> + "application/octet-stream" + end + end) + + case match do + {:ok, type} -> type + _e -> "application/octet-stream" + end + end end