text: /*
   * libwebsockets - small server side websockets and web server implementation
   *
   * Copyright (C) 2019 - 2020 Andy Green <andy@warmcat.com>
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to
   * deal in the Software without restriction, including without limitation the
   * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
   * sell copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
   * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
   * IN THE SOFTWARE.
   */
  
  #include <private-lib-core.h>
  
  extern int
  secstream_h1(struct lws *wsi, enum lws_callback_reasons reason, void *user,
  	     void *in, size_t len);
  
  static int
  secstream_h2(struct lws *wsi, enum lws_callback_reasons reason, void *user,
  	     void *in, size_t len)
  {
  	lws_ss_handle_t *h = (lws_ss_handle_t *)lws_get_opaque_user_data(wsi);
  	int n;
  
  	switch (reason) {
  
  	case LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP:
  
  #if defined(LWS_WITH_SECURE_STREAMS_PROXY_API)
  		if (h->being_serialized) {
  			/*
  			 * We are the proxy-side SS for a remote client... we
  			 * need to inform the client about the initial tx credit
  			 * to write to it that the remote h2 server set up
  			 */
  			lwsl_info("%s: reporting initial tx cr from server %d\n",
  				  __func__, wsi->txc.tx_cr);
  			ss_proxy_onward_txcr((void *)&h[1], wsi->txc.tx_cr);
  		}
  #endif
  
  		n = secstream_h1(wsi, reason, user, in, len);
  
  		if (!n && (h->policy->flags & LWSSSPOLF_LONG_POLL)) {
  			lwsl_notice("%s: h2 client %p entering LONG_POLL\n",
  					__func__, wsi);
  			lws_h2_client_stream_long_poll_rxonly(wsi);
  		}
  		return n;
  
  	case LWS_CALLBACK_COMPLETED_CLIENT_HTTP:
  		// lwsl_err("%s: h2 COMPLETED_CLIENT_HTTP\n", __func__);
  		h->info.rx(ss_to_userobj(h), NULL, 0, LWSSS_FLAG_EOM);
  		h->wsi = NULL;
  		h->txn_ok = 1;
  		//bad = status != 200;
  		lws_cancel_service(lws_get_context(wsi)); /* abort poll wait */
  		break;
  
  	case LWS_CALLBACK_WSI_TX_CREDIT_GET:
  		/*
  		 * The peer has sent us additional tx credit...
  		 */
  		lwsl_info("%s: LWS_CALLBACK_WSI_TX_CREDIT_GET: %d\n",
  			    __func__, (int32_t)len);
  
  #if defined(LWS_WITH_SECURE_STREAMS_PROXY_API)
  		if (h->being_serialized)
  			/* we are the proxy-side SS for a remote client */
  			ss_proxy_onward_txcr((void *)&h[1], (int)len);
  #endif
  		break;
  
  	default:
  		break;
  	}
  
  	return secstream_h1(wsi, reason, user, in, len);
  }
  
  const struct lws_protocols protocol_secstream_h2 = {
  	"lws-secstream-h2",
  	secstream_h2,
  	0,
  	0,
  };
  
  /*
   * Munge connect info according to protocol-specific considerations... this
   * usually means interpreting aux in a protocol-specific way and using the
   * pieces at connection setup time, eg, http url pieces.
   *
   * len bytes of buf can be used for things with scope until after the actual
   * connect.
   */
  
  int
  secstream_connect_munge_h2(lws_ss_handle_t *h, char *buf, size_t len,
  			   struct lws_client_connect_info *i,
  			   union lws_ss_contemp *ct)
  {
  	const char *pbasis = h->policy->u.http.url;
  	size_t used_in, used_out;
  	lws_strexp_t exp;
  
  	/* i.path on entry is used to override the policy urlpath if not "" */
  
  	if (i->path[0])
  		pbasis = i->path;
  
  	if (h->policy->flags & LWSSSPOLF_QUIRK_NGHTTP2_END_STREAM)
  		i->ssl_connection |= LCCSCF_H2_QUIRK_NGHTTP2_END_STREAM;
  
  	if (h->policy->flags & LWSSSPOLF_H2_QUIRK_OVERFLOWS_TXCR)
  		i->ssl_connection |= LCCSCF_H2_QUIRK_OVERFLOWS_TXCR;
  
  	if (h->policy->flags & LWSSSPOLF_HTTP_MULTIPART)
  		i->ssl_connection |= LCCSCF_HTTP_MULTIPART_MIME;
  
  	if (h->policy->flags & LWSSSPOLF_HTTP_X_WWW_FORM_URLENCODED)
  		i->ssl_connection |= LCCSCF_HTTP_X_WWW_FORM_URLENCODED;
  
  	i->ssl_connection |= LCCSCF_PIPELINE;
  
  	i->alpn = "h2";
  
  	/* initial peer tx credit */
  
  	if (h->info.manual_initial_tx_credit) {
  		i->ssl_connection |= LCCSCF_H2_MANUAL_RXFLOW;
  		i->manual_initial_tx_credit = h->info.manual_initial_tx_credit;
  		lwsl_info("%s: initial txcr %d\n", __func__,
  				i->manual_initial_tx_credit);
  	}
  
  	if (!pbasis)
  		return 0;
  
  	/* protocol aux is the path part */
  
  	i->path = buf;
  	buf[0] = '/';
  
  	lws_strexp_init(&exp, (void *)h, lws_ss_exp_cb_metadata, buf + 1, len - 1);
  
  	if (lws_strexp_expand(&exp, pbasis, strlen(pbasis),
  			      &used_in, &used_out) != LSTRX_DONE)
  		return 1;
  
  	return 0;
  }
  
  static int
  secstream_tx_credit_add_h2(lws_ss_handle_t *h, int add)
  {
  	lwsl_info("%s: h %p: add %d\n", __func__, h, add);
  	if (h->wsi)
  		return lws_h2_update_peer_txcredit(h->wsi, LWS_H2_STREAM_SID, add);
  
  	return 0;
  }
  
  static int
  secstream_tx_credit_est_h2(lws_ss_handle_t *h)
  {
  	if (h->wsi) {
  		lwsl_info("%s: h %p: est %d\n", __func__, h,
  				lws_h2_get_peer_txcredit_estimate(h->wsi));
  
  		return lws_h2_get_peer_txcredit_estimate(h->wsi);
  	}
  
  	lwsl_info("%s: h %p: Unknown (0)\n", __func__, h);
  
  	return 0;
  }
  
  const struct ss_pcols ss_pcol_h2 = {
  	"h2",
  	NULL,
  	"lws-secstream-h2",
  	secstream_connect_munge_h2,
  	secstream_tx_credit_add_h2,
  	secstream_tx_credit_est_h2
  };
  