1/*
2 * libwebsockets - small server side websockets and web server implementation
3 *
4 * Copyright (C) 2019 - 2020 Andy Green <andy@warmcat.com>
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22 * IN THE SOFTWARE.
23 */
24
25#include <private-lib-core.h>
26
27extern int
28secstream_h1(struct lws *wsi, enum lws_callback_reasons reason, void *user,
29	     void *in, size_t len);
30
31static int
32secstream_h2(struct lws *wsi, enum lws_callback_reasons reason, void *user,
33	     void *in, size_t len)
34{
35	lws_ss_handle_t *h = (lws_ss_handle_t *)lws_get_opaque_user_data(wsi);
36	lws_ss_state_return_t r;
37	int n;
38
39	switch (reason) {
40
41	case LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP:
42
43		if (!h)
44			return -1;
45
46#if defined(LWS_WITH_SECURE_STREAMS_PROXY_API)
47		if (h->being_serialized) {
48			/*
49			 * We are the proxy-side SS for a remote client... we
50			 * need to inform the client about the initial tx credit
51			 * to write to it that the remote h2 server set up
52			 */
53			lwsl_info("%s: reporting initial tx cr from server %d\n",
54				  __func__, wsi->txc.tx_cr);
55			ss_proxy_onward_txcr((void *)(h + 1), wsi->txc.tx_cr);
56		}
57#endif
58
59		n = secstream_h1(wsi, reason, user, in, len);
60
61		if (!n && (h->policy->flags & LWSSSPOLF_LONG_POLL)) {
62			lwsl_notice("%s: h2 client %s entering LONG_POLL\n",
63					__func__, lws_wsi_tag(wsi));
64			lws_h2_client_stream_long_poll_rxonly(wsi);
65		}
66		return n;
67
68	case LWS_CALLBACK_CLOSED_CLIENT_HTTP:
69		/*
70		 * Only allow the wsi that the handle believes is representing
71		 * him to report closure up to h1
72		 */
73		if (!h || h->wsi != wsi)
74			return 0;
75
76		break;
77
78	case LWS_CALLBACK_COMPLETED_CLIENT_HTTP:
79
80		if (!h)
81			return -1;
82
83		// lwsl_err("%s: h2 COMPLETED_CLIENT_HTTP\n", __func__);
84		r = 0;
85		if (h->hanging_som)
86			r = h->info.rx(ss_to_userobj(h), NULL, 0, LWSSS_FLAG_EOM);
87
88		h->txn_ok = 1;
89		lws_cancel_service(lws_get_context(wsi)); /* abort poll wait */
90		if (h->hanging_som && r == LWSSSSRET_DESTROY_ME)
91			return _lws_ss_handle_state_ret_CAN_DESTROY_HANDLE(r, wsi, &h);
92		h->hanging_som = 0;
93		break;
94
95	case LWS_CALLBACK_WSI_TX_CREDIT_GET:
96
97		if (!h)
98			return -1;
99
100		/*
101		 * The peer has sent us additional tx credit...
102		 */
103		lwsl_info("%s: LWS_CALLBACK_WSI_TX_CREDIT_GET: %d\n",
104			    __func__, (int)len);
105
106#if defined(LWS_WITH_SECURE_STREAMS_PROXY_API)
107		if (h->being_serialized)
108			/* we are the proxy-side SS for a remote client */
109			ss_proxy_onward_txcr((void *)(h + 1), (int)len);
110#endif
111		break;
112
113	default:
114		break;
115	}
116
117	return secstream_h1(wsi, reason, user, in, len);
118}
119
120const struct lws_protocols protocol_secstream_h2 = {
121	"lws-secstream-h2",
122	secstream_h2,
123	0, 0, 0, NULL, 0
124};
125
126/*
127 * Munge connect info according to protocol-specific considerations... this
128 * usually means interpreting aux in a protocol-specific way and using the
129 * pieces at connection setup time, eg, http url pieces.
130 *
131 * len bytes of buf can be used for things with scope until after the actual
132 * connect.
133 */
134
135int
136secstream_connect_munge_h2(lws_ss_handle_t *h, char *buf, size_t len,
137			   struct lws_client_connect_info *i,
138			   union lws_ss_contemp *ct)
139{
140	const char *pbasis = h->policy->u.http.url;
141	size_t used_in, used_out;
142	lws_strexp_t exp;
143
144	/* i.path on entry is used to override the policy urlpath if not "" */
145
146	if (i->path[0])
147		pbasis = i->path;
148
149	if (h->policy->flags & LWSSSPOLF_QUIRK_NGHTTP2_END_STREAM)
150		i->ssl_connection |= LCCSCF_H2_QUIRK_NGHTTP2_END_STREAM;
151
152	if (h->policy->flags & LWSSSPOLF_H2_QUIRK_OVERFLOWS_TXCR)
153		i->ssl_connection |= LCCSCF_H2_QUIRK_OVERFLOWS_TXCR;
154
155	if (h->policy->flags & LWSSSPOLF_HTTP_MULTIPART)
156		i->ssl_connection |= LCCSCF_HTTP_MULTIPART_MIME;
157
158	if (h->policy->flags & LWSSSPOLF_HTTP_X_WWW_FORM_URLENCODED)
159		i->ssl_connection |= LCCSCF_HTTP_X_WWW_FORM_URLENCODED;
160
161	if (h->policy->flags & LWSSSPOLF_HTTP_CACHE_COOKIES)
162		i->ssl_connection |= LCCSCF_CACHE_COOKIES;
163
164	i->ssl_connection |= LCCSCF_PIPELINE;
165
166	i->alpn = "h2";
167
168	/* initial peer tx credit */
169
170	if (h->info.manual_initial_tx_credit) {
171		i->ssl_connection |= LCCSCF_H2_MANUAL_RXFLOW;
172		i->manual_initial_tx_credit = h->info.manual_initial_tx_credit;
173		lwsl_info("%s: initial txcr %d\n", __func__,
174				i->manual_initial_tx_credit);
175	}
176
177	if (!pbasis)
178		return 0;
179
180	/* protocol aux is the path part */
181
182	i->path = buf;
183	buf[0] = '/';
184
185	lws_strexp_init(&exp, (void *)h, lws_ss_exp_cb_metadata, buf + 1, len - 1);
186
187	if (lws_strexp_expand(&exp, pbasis, strlen(pbasis),
188			      &used_in, &used_out) != LSTRX_DONE)
189		return 1;
190
191	return 0;
192}
193
194static int
195secstream_tx_credit_add_h2(lws_ss_handle_t *h, int add)
196{
197	lwsl_info("%s: %s: add %d\n", __func__, lws_ss_tag(h), add);
198	if (h->wsi)
199		return lws_h2_update_peer_txcredit(h->wsi, (unsigned int)LWS_H2_STREAM_SID, add);
200
201	return 0;
202}
203
204static int
205secstream_tx_credit_est_h2(lws_ss_handle_t *h)
206{
207	if (h->wsi) {
208		lwsl_info("%s: %s: est %d\n", __func__, lws_ss_tag(h),
209				lws_h2_get_peer_txcredit_estimate(h->wsi));
210
211		return lws_h2_get_peer_txcredit_estimate(h->wsi);
212	}
213
214	lwsl_info("%s: %s: Unknown (0)\n", __func__, lws_ss_tag(h));
215
216	return 0;
217}
218
219const struct ss_pcols ss_pcol_h2 = {
220	"h2",
221	"h2",
222	&protocol_secstream_h2,
223	secstream_connect_munge_h2,
224	secstream_tx_credit_add_h2,
225	secstream_tx_credit_est_h2
226};
227