+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2018 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
defmodule Pleroma.HTML do
alias HtmlSanitizeEx.Scrubber
+ defp get_scrubbers(scrubber) when is_atom(scrubber), do: [scrubber]
+ defp get_scrubbers(scrubbers) when is_list(scrubbers), do: scrubbers
+ defp get_scrubbers(_), do: [Pleroma.HTML.Scrubber.Default]
+
+ def get_scrubbers() do
+ Pleroma.Config.get([:markup, :scrub_policy])
+ |> get_scrubbers
+ end
+
+ def filter_tags(html, nil) do
+ get_scrubbers()
+ |> Enum.reduce(html, fn scrubber, html ->
+ filter_tags(html, scrubber)
+ end)
+ end
+
+ def filter_tags(html, scrubber), do: Scrubber.scrub(html, scrubber)
+ def filter_tags(html), do: filter_tags(html, nil)
+ def strip_tags(html), do: Scrubber.scrub(html, Scrubber.StripTags)
+end
+
+defmodule Pleroma.HTML.Scrubber.TwitterText do
+ @moduledoc """
+ An HTML scrubbing policy which limits to twitter-style text. Only
+ paragraphs, breaks and links are allowed through the filter.
+ """
+
@markup Application.get_env(:pleroma, :markup)
+ @uri_schemes Application.get_env(:pleroma, :uri_schemes, [])
+ @valid_schemes Keyword.get(@uri_schemes, :valid_schemes, [])
+
+ require HtmlSanitizeEx.Scrubber.Meta
+ alias HtmlSanitizeEx.Scrubber.Meta
+
+ Meta.remove_cdata_sections_before_scrub()
+ Meta.strip_comments()
+
+ # links
+ Meta.allow_tag_with_uri_attributes("a", ["href", "data-user", "data-tag"], @valid_schemes)
+ Meta.allow_tag_with_these_attributes("a", ["name", "title"])
+
+ # paragraphs and linebreaks
+ Meta.allow_tag_with_these_attributes("br", [])
+ Meta.allow_tag_with_these_attributes("p", [])
- def filter_tags(html) do
- scrubber = Keyword.get(@markup, :scrub_policy)
- html |> Scrubber.scrub(scrubber)
+ # microformats
+ Meta.allow_tag_with_these_attributes("span", [])
+
+ # allow inline images for custom emoji
+ @allow_inline_images Keyword.get(@markup, :allow_inline_images)
+
+ if @allow_inline_images do
+ # restrict img tags to http/https only, because of MediaProxy.
+ Meta.allow_tag_with_uri_attributes("img", ["src"], ["http", "https"])
+
+ Meta.allow_tag_with_these_attributes("img", [
+ "width",
+ "height",
+ "title",
+ "alt"
+ ])
end
- def strip_tags(html) do
- html |> Scrubber.scrub(Scrubber.StripTags)
+ Meta.strip_everything_not_covered()
+end
+
+defmodule Pleroma.HTML.Scrubber.Default do
+ @doc "The default HTML scrubbing policy: no "
+
+ require HtmlSanitizeEx.Scrubber.Meta
+ alias HtmlSanitizeEx.Scrubber.Meta
+
+ @markup Application.get_env(:pleroma, :markup)
+ @uri_schemes Application.get_env(:pleroma, :uri_schemes, [])
+ @valid_schemes Keyword.get(@uri_schemes, :valid_schemes, [])
+
+ Meta.remove_cdata_sections_before_scrub()
+ Meta.strip_comments()
+
+ Meta.allow_tag_with_uri_attributes("a", ["href", "data-user", "data-tag"], @valid_schemes)
+ Meta.allow_tag_with_these_attributes("a", ["name", "title"])
+
+ Meta.allow_tag_with_these_attributes("abbr", ["title"])
+
+ Meta.allow_tag_with_these_attributes("b", [])
+ Meta.allow_tag_with_these_attributes("blockquote", [])
+ Meta.allow_tag_with_these_attributes("br", [])
+ Meta.allow_tag_with_these_attributes("code", [])
+ Meta.allow_tag_with_these_attributes("del", [])
+ Meta.allow_tag_with_these_attributes("em", [])
+ Meta.allow_tag_with_these_attributes("i", [])
+ Meta.allow_tag_with_these_attributes("li", [])
+ Meta.allow_tag_with_these_attributes("ol", [])
+ Meta.allow_tag_with_these_attributes("p", [])
+ Meta.allow_tag_with_these_attributes("pre", [])
+ Meta.allow_tag_with_these_attributes("span", [])
+ Meta.allow_tag_with_these_attributes("strong", [])
+ Meta.allow_tag_with_these_attributes("u", [])
+ Meta.allow_tag_with_these_attributes("ul", [])
+
+ @allow_inline_images Keyword.get(@markup, :allow_inline_images)
+
+ if @allow_inline_images do
+ # restrict img tags to http/https only, because of MediaProxy.
+ Meta.allow_tag_with_uri_attributes("img", ["src"], ["http", "https"])
+
+ Meta.allow_tag_with_these_attributes("img", [
+ "width",
+ "height",
+ "title",
+ "alt"
+ ])
end
+
+ @allow_tables Keyword.get(@markup, :allow_tables)
+
+ if @allow_tables do
+ Meta.allow_tag_with_these_attributes("table", [])
+ Meta.allow_tag_with_these_attributes("tbody", [])
+ Meta.allow_tag_with_these_attributes("td", [])
+ Meta.allow_tag_with_these_attributes("th", [])
+ Meta.allow_tag_with_these_attributes("thead", [])
+ Meta.allow_tag_with_these_attributes("tr", [])
+ end
+
+ @allow_headings Keyword.get(@markup, :allow_headings)
+
+ if @allow_headings do
+ Meta.allow_tag_with_these_attributes("h1", [])
+ Meta.allow_tag_with_these_attributes("h2", [])
+ Meta.allow_tag_with_these_attributes("h3", [])
+ Meta.allow_tag_with_these_attributes("h4", [])
+ Meta.allow_tag_with_these_attributes("h5", [])
+ end
+
+ @allow_fonts Keyword.get(@markup, :allow_fonts)
+
+ if @allow_fonts do
+ Meta.allow_tag_with_these_attributes("font", ["face"])
+ end
+
+ Meta.strip_everything_not_covered()
+end
+
+defmodule Pleroma.HTML.Transform.MediaProxy do
+ @moduledoc "Transforms inline image URIs to use MediaProxy."
+
+ alias Pleroma.Web.MediaProxy
+
+ def before_scrub(html), do: html
+
+ def scrub_attribute("img", {"src", "http" <> target}) do
+ media_url =
+ ("http" <> target)
+ |> MediaProxy.url()
+
+ {"src", media_url}
+ end
+
+ def scrub_attribute(_tag, attribute), do: attribute
+
+ def scrub({"img", attributes, children}) do
+ attributes =
+ attributes
+ |> Enum.map(fn attr -> scrub_attribute("img", attr) end)
+ |> Enum.reject(&is_nil(&1))
+
+ {"img", attributes, children}
+ end
+
+ def scrub({:comment, _children}), do: ""
+
+ def scrub({tag, attributes, children}), do: {tag, attributes, children}
+ def scrub({_tag, children}), do: children
+ def scrub(text), do: text
end
projects / akkoma / blobdiff