view mod_http_avatar/mod_http_avatar.lua @ 4651:8231774f5bfd

mod_cloud_notify_encrypted: Ensure body substring remains valid UTF-8 The `body:sub()` call risks splitting the string in the middle of a multi-byte UTF-8 sequence. This should have been caught by util.stanza validation, but that would have caused some havoc, at the very least causing the notification to not be sent. There have been no reports of this happening. Likely because this module isn't widely deployed among users with languages that use many longer UTF-8 sequences. The util.encodings.utf8.valid() function is O(n) where only the last sequence really needs to be checked, but it's in C and expected to be fast.
author Kim Alvefur <zash@zash.se>
date Sun, 22 Aug 2021 13:22:59 +0200
parents 5b4e7db5943c
children 0f103a6e9ba4
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-- Prosody IM
-- Copyright (C) 2018 Emmanuel Gil Peyrot
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.

local base64 = require"util.encodings".base64;
local sha1 = require"util.hashes".sha1;
local st = require"util.stanza";
module:depends"http";

local vcard_storage = module:open_store"vcard";

local default_avatar = [[<svg xmlns='http://www.w3.org/2000/svg' version='1.1' viewBox='0 0 150 150'>
<rect width='150' height='150' fill='#888' stroke-width='1' stroke='#000'/>
<text x='75' y='100' text-anchor='middle' font-size='100'>?</text>
</svg>]];

local function get_avatar(event, path)
	local request, response = event.request, event.response;
	local photo_type, binval;
	local vcard, err = vcard_storage:get(path);
	if vcard then
		vcard = st.deserialize(vcard);
		local photo = vcard:get_child("PHOTO", "vcard-temp");
		if photo then
			photo_type = photo:get_child_text("TYPE", "vcard-temp");
			binval = photo:get_child_text("BINVAL", "vcard-temp");
		end
	end
	if not photo_type or not binval then
		response.status_code = 404;
		response.headers.content_type = "image/svg+xml";
		return default_avatar;
	end
	local avatar = base64.decode(binval);
	local hash = sha1(avatar, true);
	if request.headers.if_none_match == hash then
		return 304;
	end
	response.headers.content_type = photo_type;
	response.headers.etag = hash;
	return avatar;
end

module:provides("http", {
	route = {
		["GET /*"] = get_avatar;
	};
});