mod_proxy_websocket.c revision 27774671fd435737640c3631e23db369500ca66a
/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "mod_proxy.h"
module AP_MODULE_DECLARE_DATA proxy_websocket_module;
/*
* Canonicalise http-like URLs.
* scheme is the scheme for the URL
* url is the URL starting with the first '/'
* def_port is the default port for this scheme.
*/
static int proxy_websocket_canon(request_rec *r, char *url)
{
char *host, *path, sport[7];
char *search = NULL;
const char *err;
char *scheme;
apr_port_t port, def_port;
/* ap_port_of_scheme() */
if (strncasecmp(url, "ws:", 3) == 0) {
url += 3;
scheme = "ws:";
def_port = apr_uri_port_of_scheme("http");
}
else if (strncasecmp(url, "wss:", 4) == 0) {
url += 4;
scheme = "wss:";
def_port = apr_uri_port_of_scheme("https");
}
else {
return DECLINED;
}
port = def_port;
ap_log_rerror(APLOG_MARK, APLOG_TRACE1, 0, r, "canonicalising URL %s", url);
/*
* do syntactic check.
* We break the URL into host, port, path, search
*/
err = ap_proxy_canon_netloc(r->pool, &url, NULL, NULL, &host, &port);
if (err) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO() "error parsing URL %s: %s",
url, err);
return HTTP_BAD_REQUEST;
}
/*
* now parse path/search args, according to rfc1738:
* process the path. With proxy-nocanon set (by
* mod_proxy) we use the raw, unparsed uri
*/
if (apr_table_get(r->notes, "proxy-nocanon")) {
path = url; /* this is the raw path */
}
else {
path = ap_proxy_canonenc(r->pool, url, strlen(url), enc_path, 0,
r->proxyreq);
search = r->args;
}
if (path == NULL)
return HTTP_BAD_REQUEST;
apr_snprintf(sport, sizeof(sport), ":%d", port);
if (ap_strchr_c(host, ':')) {
/* if literal IPv6 address */
host = apr_pstrcat(r->pool, "[", host, "]", NULL);
}
r->filename = apr_pstrcat(r->pool, "proxy:", scheme, "//", host, sport,
"/", path, (search) ? "?" : "",
(search) ? search : "", NULL);
return OK;
}
static int proxy_websocket_transfer(request_rec *r, conn_rec *c_i, conn_rec *c_o,
apr_bucket_brigade *bb, char *name)
{
int rv;
#ifdef DEBUGGING
apr_off_t len;
#endif
do {
apr_brigade_cleanup(bb);
rv = ap_get_brigade(c_i->input_filters, bb, AP_MODE_READBYTES,
APR_NONBLOCK_READ, AP_IOBUFSIZE);
if (rv == APR_SUCCESS) {
if (c_o->aborted)
return APR_EPIPE;
if (APR_BRIGADE_EMPTY(bb))
break;
#ifdef DEBUGGING
len = -1;
apr_brigade_length(bb, 0, &len);
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO()
"read %" APR_OFF_T_FMT
" bytes from %s", len, name);
#endif
rv = ap_pass_brigade(c_o->output_filters, bb);
if (rv == APR_SUCCESS) {
ap_fflush(c_o->output_filters, bb);
}
else {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO()
"error on %s - ap_pass_brigade",
name);
}
} else if (!APR_STATUS_IS_EAGAIN(rv) && !APR_STATUS_IS_EOF(rv)) {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv, r, APLOGNO()
"error on %s - ap_get_brigade",
name);
}
} while (rv == APR_SUCCESS);
if (APR_STATUS_IS_EAGAIN(rv)) {
rv = APR_SUCCESS;
}
return rv;
}
/*
* process the request and write the response.
*/
static int ap_proxy_websocket_request(apr_pool_t *p, request_rec *r,
proxy_conn_rec *conn,
proxy_worker *worker,
proxy_server_conf *conf,
apr_uri_t *uri,
char *url, char *server_portstr)
{
apr_status_t rv = APR_SUCCESS;
apr_pollset_t *pollset;
apr_pollfd_t pollfd;
const apr_pollfd_t *signalled;
apr_int32_t pollcnt, pi;
apr_int16_t pollevent;
conn_rec *c = r->connection;
apr_socket_t *sock = conn->sock;
conn_rec *backconn = conn->connection;
int client_error = 0;
char *buf;
apr_size_t blen;
apr_bucket_brigade *header_brigade;
apr_bucket *e;
char *old_cl_val = NULL;
char *old_te_val = NULL;
apr_bucket_brigade *bb = apr_brigade_create(p, c->bucket_alloc);
apr_socket_t *client_socket = ap_get_conn_socket(c);
header_brigade = apr_brigade_create(p, backconn->bucket_alloc);
ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r, "sending request");
rv = ap_proxy_create_hdrbrgd(p, header_brigade, r, conn,
worker, conf, uri, url, server_portstr,
&old_cl_val, &old_te_val);
if (rv != OK) {
return rv;
}
buf = CRLF;
blen = strlen(buf);
ap_xlate_proto_to_ascii(buf, strlen(buf));
e = apr_bucket_pool_create(buf, strlen(buf), p, c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(header_brigade, e);
if ((rv = ap_proxy_pass_brigade(c->bucket_alloc, r, conn, backconn,
header_brigade, 1)) != OK)
return rv;
ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r, "setting up poll()");
if ((rv = apr_pollset_create(&pollset, 2, p, 0)) != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO()
"error apr_pollset_create()");
return HTTP_INTERNAL_SERVER_ERROR;
}
#if 0
apr_socket_opt_set(sock, APR_SO_NONBLOCK, 1);
apr_socket_opt_set(sock, APR_SO_KEEPALIVE, 1);
apr_socket_opt_set(client_socket, APR_SO_NONBLOCK, 1);
apr_socket_opt_set(client_socket, APR_SO_KEEPALIVE, 1);
#endif
pollfd.p = p;
pollfd.desc_type = APR_POLL_SOCKET;
pollfd.reqevents = APR_POLLIN;
pollfd.desc.s = sock;
pollfd.client_data = NULL;
apr_pollset_add(pollset, &pollfd);
pollfd.desc.s = client_socket;
apr_pollset_add(pollset, &pollfd);
r->output_filters = c->output_filters;
r->proto_output_filters = c->output_filters;
r->input_filters = c->input_filters;
r->proto_input_filters = c->input_filters;
while (1) { /* Infinite loop until error (one side closes the connection) */
if ((rv = apr_pollset_poll(pollset, -1, &pollcnt, &signalled))
!= APR_SUCCESS) {
if (APR_STATUS_IS_EINTR(rv)) {
continue;
}
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO() "error apr_poll()");
return HTTP_INTERNAL_SERVER_ERROR;
}
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO()
"woke from poll(), i=%d", pollcnt);
for (pi = 0; pi < pollcnt; pi++) {
const apr_pollfd_t *cur = &signalled[pi];
if (cur->desc.s == sock) {
pollevent = cur->rtnevents;
if (pollevent & APR_POLLIN) {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO()
"sock was readable");
rv = proxy_websocket_transfer(r, backconn, c, bb, "sock");
}
else if ((pollevent & APR_POLLERR)
|| (pollevent & APR_POLLHUP)) {
rv = APR_EPIPE;
ap_log_rerror(APLOG_MARK, APLOG_NOTICE, 0, r, APLOGNO()
"err/hup on backconn");
}
if (rv != APR_SUCCESS)
client_error = 1;
}
else if (cur->desc.s == client_socket) {
pollevent = cur->rtnevents;
if (pollevent & APR_POLLIN) {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO()
"client was readable");
rv = proxy_websocket_transfer(r, c, backconn, bb, "client");
}
}
else {
rv = APR_EBADF;
ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO()
"unknown socket in pollset");
}
}
if (rv != APR_SUCCESS) {
break;
}
}
ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r,
"finished with poll() - cleaning up");
if (client_error) {
return HTTP_INTERNAL_SERVER_ERROR;
}
return OK;
}
/*
*/
static int proxy_websocket_handler(request_rec *r, proxy_worker *worker,
proxy_server_conf *conf,
char *url, const char *proxyname,
apr_port_t proxyport)
{
int status;
char server_portstr[32];
proxy_conn_rec *backend = NULL;
char *scheme;
int retry;
conn_rec *c = r->connection;
apr_pool_t *p = r->pool;
apr_uri_t *uri;
if (strncasecmp(url, "wss:", 4) == 0) {
scheme = "WSS";
}
else if (strncasecmp(url, "ws:", 3) == 0) {
scheme = "WS";
}
else {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO() "declining URL %s", url);
return DECLINED;
}
uri = apr_palloc(p, sizeof(*uri));
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO() "serving URL %s", url);
/* create space for state information */
status = ap_proxy_acquire_connection(scheme, &backend, worker,
r->server);
if (status != OK) {
if (backend) {
backend->close = 1;
ap_proxy_release_connection(scheme, backend, r->server);
}
return status;
}
backend->is_ssl = 0;
backend->close = 0;
retry = 0;
while (retry < 2) {
char *locurl = url;
/* Step One: Determine Who To Connect To */
status = ap_proxy_determine_connection(p, r, conf, worker, backend,
uri, &locurl, proxyname, proxyport,
server_portstr,
sizeof(server_portstr));
if (status != OK)
break;
/* Step Two: Make the Connection */
if (ap_proxy_connect_backend(scheme, backend, worker, r->server)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO()
"failed to make connection to backend: %s",
backend->hostname);
status = HTTP_SERVICE_UNAVAILABLE;
break;
}
/* Step Three: Create conn_rec */
if (!backend->connection) {
if ((status = ap_proxy_connection_create(scheme, backend,
c, r->server)) != OK)
break;
}
/* Step Three: Process the Request */
status = ap_proxy_websocket_request(p, r, backend, worker, conf, uri, locurl,
server_portstr);
break;
}
/* Do not close the socket */
ap_proxy_release_connection(scheme, backend, r->server);
return status;
}
static void ap_proxy_http_register_hook(apr_pool_t *p)
{
proxy_hook_scheme_handler(proxy_websocket_handler, NULL, NULL, APR_HOOK_FIRST);
proxy_hook_canon_handler(proxy_websocket_canon, NULL, NULL, APR_HOOK_FIRST);
}
AP_DECLARE_MODULE(proxy_websocket) = {
STANDARD20_MODULE_STUFF,
NULL, /* create per-directory config structure */
NULL, /* merge per-directory config structures */
NULL, /* create per-server config structure */
NULL, /* merge per-server config structures */
NULL, /* command apr_table_t */
ap_proxy_http_register_hook /* register hooks */
};