aboutsummaryrefslogtreecommitdiffstats
path: root/plugins/mod_http_file_share.lua
blob: ef427b94591355238035c760353d0f9d91504a18 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
-- Prosody IM
-- Copyright (C) 2021 Kim Alvefur
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--
-- XEP-0363: HTTP File Upload
-- Again, from the top!

local t_insert = table.insert;
local jid = require "util.jid";
local st = require "util.stanza";
local url = require "socket.url";
local dm = require "core.storagemanager".olddm;
local jwt = require "util.jwt";
local errors = require "util.error";
local dataform = require "util.dataforms".new;

local namespace = "urn:xmpp:http:upload:0";

module:depends("disco");

module:add_identity("store", "file", module:get_option_string("name", "HTTP File Upload"));
module:add_feature(namespace);

local uploads = module:open_store("uploads", "archive");
-- id, <request>, time, owner

local secret = module:get_option_string(module.name.."_secret", require"util.id".long());
local external_base_url = module:get_option_string(module.name .. "_base_url");
local file_size_limit = module:get_option_number(module.name .. "_size_limit", 10 * 1024 * 1024); -- 10 MB
local file_types = module:get_option_set(module.name .. "_allowed_file_types", {});

local access = module:get_option_set(module.name .. "_access", {});

if not external_base_url then
	module:depends("http");
end

module:add_extension(dataform {
	{ name = "FORM_TYPE", type = "hidden", value = namespace },
	{ name = "max-file-size", type = "text-single" },
}:form({ ["max-file-size"] = tostring(file_size_limit) }, "result"));

local upload_errors = errors.init(module.name, namespace, {
	access = { "auth"; "forbidden" };
	filename = { "modify"; "bad-request", "Invalid filename" };
	filetype = { "modify"; "not-acceptable", "File type not allowed" };
	filesize = { "modify"; "not-acceptable"; "File too large";
		st.stanza("file-too-large", {xmlns = namespace}):tag("max-size"):text(tostring(file_size_limit)); };
});

function may_upload(uploader, filename, filesize, filetype) -- > boolean, error
	local uploader_host = jid.host(uploader);
	if not ((access:empty() and prosody.hosts[uploader_host]) or access:contains(uploader) or access:contains(uploader_host)) then
		return false, upload_errors.new("access");
	end

	if not filename or filename:find"/" then
		-- On Linux, only '/' and '\0' are invalid in filenames and NUL can't be in XML
		return false, upload_errors.new("filename");
	end

	if filesize > file_size_limit then
		return false, upload_errors.new("filesize");
	end

	if not ( file_types:empty() or file_types:contains(filetype) or file_types:contains(filetype:gsub("/.*", "/*")) ) then
		return false, upload_errors.new("filetype");
	end

	return true;
end

function get_authz(uploader, filename, filesize, filetype, slot)
	return "Bearer "..jwt.sign(secret, {
		sub = uploader;
		filename = filename;
		filesize = filesize;
		filetype = filetype;
		slot = slot;
		exp = os.time()+300;
	});
end

function get_url(slot, filename)
	local base_url = external_base_url or module:http_url();
	local slot_url = url.parse(base_url);
	slot_url.path = url.parse_path(slot_url.path or "/");
	t_insert(slot_url.path, slot);
	if filename then
		t_insert(slot_url.path, filename);
		slot_url.path.is_directory = false;
	else
		slot_url.path.is_directory = true;
	end
	slot_url.path = url.build_path(slot_url.path);
	return url.build(slot_url);
end

function handle_slot_request(event)
	local stanza, origin = event.stanza, event.origin;

	local request = st.clone(stanza.tags[1], true);
	local filename = request.attr.filename;
	local filesize = tonumber(request.attr.size);
	local filetype = request.attr["content-type"];
	local uploader = jid.bare(stanza.attr.from);

	local may, why_not = may_upload(uploader, filename, filesize, filetype);
	if not may then
		origin.send(st.error_reply(stanza, why_not));
		return true;
	end

	local slot, storage_err = errors.coerce(uploads:append(nil, nil, request, os.time(), uploader))
	if not slot then
		origin.send(st.error_reply(stanza, storage_err));
		return true;
	end

	local authz = get_authz(uploader, filename, filesize, filetype, slot);
	local slot_url = get_url(slot, filename);
	local upload_url = slot_url;

	local reply = st.reply(stanza)
		:tag("slot", { xmlns = namespace })
			:tag("get", { url = slot_url }):up()
			:tag("put", { url = upload_url })
				:text_tag("header", authz, {name="Authorization"})
		:reset();

	origin.send(reply);
	return true;
end

function handle_upload(event, path) -- PUT /upload/:slot
	local request = event.request;
	local authz = request.headers.authorization;
	if not authz or not authz:find"^Bearer ." then
		return 403;
	end
	local authed, upload_info = jwt.verify(secret, authz:match("^Bearer (.*)"));
	if not (authed and type(upload_info) == "table" and type(upload_info.exp) == "number") then
		return 401;
	end
	if upload_info.exp < os.time() then
		return 410;
	end
	if not path or upload_info.slot ~= path:match("^[^/]+") then
		return 400;
	end

	local filename = dm.getpath(upload_info.slot, module.host, module.name, nil, true);

	if not request.body_sink then
		local fh, err = errors.coerce(io.open(filename.."~", "w"));
		if not fh then
			return err;
		end
		request.body_sink = fh;
		if request.body == false then
			return true;
		end
	end

	if request.body then
		local written, err = errors.coerce(request.body_sink:write(request.body));
		if not written then
			return err;
		end
		request.body = nil;
	end

	if request.body_sink then
		local final_size = request.body_sink:seek();
		local uploaded, err = errors.coerce(request.body_sink:close());
		if final_size ~= upload_info.filesize then
			-- Could be too short as well, but we say the same thing
			uploaded, err = false, 413;
		end
		if uploaded then
			assert(os.rename(filename.."~", filename));
			return 201;
		else
			assert(os.remove(filename.."~"));
			return err;
		end
	end

end

function handle_download(event, path) -- GET /uploads/:slot+filename
	local request, response = event.request, event.response;
	local slot_id = path:match("^[^/]+");
	-- TODO cache
	local slot, when = errors.coerce(uploads:get(nil, slot_id));
	if not slot then
		module:log("debug", "uploads:get(%q) --> not-found, %s", slot_id, when);
		return 404;
	end
	module:log("debug", "uploads:get(%q) --> %s, %d", slot_id, slot, when);
	local last_modified = os.date('!%a, %d %b %Y %H:%M:%S GMT', when);
	if request.headers.if_modified_since == last_modified then
		return 304;
	end
	local filename = dm.getpath(slot_id, module.host, module.name);
	local handle, ferr = errors.coerce(io.open(filename));
	if not handle then
		return ferr or 410;
	end
	response.headers.last_modified = last_modified;
	response.headers.content_length = slot.attr.size;
	response.headers.content_type = slot.attr["content-type"];
	response.headers.content_disposition = string.format("attachment; filename=%q", slot.attr.filename);

	response.headers.cache_control = "max-age=31556952, immutable";
	response.headers.content_security_policy =  "default-src 'none'; frame-ancestors 'none';"

	return response:send_file(handle);
	-- TODO
	-- Set security headers
end

-- TODO periodic cleanup job

module:hook("iq-get/host/urn:xmpp:http:upload:0:request", handle_slot_request);

if not external_base_url then
module:provides("http", {
		streaming_uploads = true;
		route = {
			["PUT /*"] = handle_upload;
			["GET /*"] = handle_download;
		}
	});
end