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/* Copyright 2015 greenbytes GmbH (https://www.greenbytes.de)
*
* Licensed 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 <assert.h>
#include <ap_mpm.h>
#include <httpd.h>
#include <http_core.h>
#include <http_config.h>
#include <http_log.h>
#include <http_connection.h>
#include <http_protocol.h>
#include <http_request.h>
#include "h2_private.h"
#include "h2_config.h"
#include "h2_ctx.h"
#include "h2_mplx.h"
#include "h2_session.h"
#include "h2_stream.h"
#include "h2_stream_set.h"
#include "h2_h2.h"
#include "h2_task.h"
#include "h2_worker.h"
#include "h2_workers.h"
#include "h2_conn.h"
static struct h2_workers *workers;
static apr_status_t h2_session_process(h2_session *session);
static h2_mpm_type_t mpm_type = H2_MPM_UNKNOWN;
static module *mpm_module;
static module *ssl_module;
static int checked;
static void check_modules(void)
{
int i;
if (!checked) {
for (i = 0; ap_loaded_modules[i]; ++i) {
module *m = ap_loaded_modules[i];
if (!strcmp("event.c", m->name)) {
mpm_type = H2_MPM_EVENT;
mpm_module = m;
}
else if (!strcmp("worker.c", m->name)) {
mpm_type = H2_MPM_WORKER;
mpm_module = m;
}
else if (!strcmp("prefork.c", m->name)) {
mpm_type = H2_MPM_PREFORK;
mpm_module = m;
}
else if (!strcmp("mod_ssl.c", m->name)) {
ssl_module = m;
}
}
checked = 1;
}
}
apr_status_t h2_conn_child_init(apr_pool_t *pool, server_rec *s)
{
h2_config *config = h2_config_sget(s);
apr_status_t status = APR_SUCCESS;
int minw = h2_config_geti(config, H2_CONF_MIN_WORKERS);
int maxw = h2_config_geti(config, H2_CONF_MAX_WORKERS);
int max_threads_per_child = 0;
int threads_limit = 0;
int idle_secs = 0;
int i;
h2_config_init(pool);
ap_mpm_query(AP_MPMQ_MAX_THREADS, &max_threads_per_child);
ap_mpm_query(AP_MPMQ_HARD_LIMIT_THREADS, &threads_limit);
for (i = 0; ap_loaded_modules[i]; ++i) {
module *m = ap_loaded_modules[i];
if (!strcmp("event.c", m->name)) {
mpm_type = H2_MPM_EVENT;
mpm_module = m;
}
else if (!strcmp("worker.c", m->name)) {
mpm_type = H2_MPM_WORKER;
mpm_module = m;
}
else if (!strcmp("prefork.c", m->name)) {
mpm_type = H2_MPM_PREFORK;
mpm_module = m;
}
else if (!strcmp("mod_ssl.c", m->name)) {
ssl_module = m;
}
}
if (minw <= 0) {
minw = max_threads_per_child;
}
if (maxw <= 0) {
maxw = threads_limit;
if (maxw < minw) {
maxw = minw;
}
}
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"h2_workers: min=%d max=%d, mthrpchild=%d, thr_limit=%d",
minw, maxw, max_threads_per_child, threads_limit);
workers = h2_workers_create(s, pool, minw, maxw);
idle_secs = h2_config_geti(config, H2_CONF_MAX_WORKER_IDLE_SECS);
h2_workers_set_max_idle_secs(workers, idle_secs);
return status;
}
h2_mpm_type_t h2_conn_mpm_type(void) {
check_modules();
return mpm_type;
}
static module *h2_conn_mpm_module(void) {
check_modules();
return mpm_module;
}
apr_status_t h2_conn_rprocess(request_rec *r)
{
h2_config *config = h2_config_rget(r);
h2_session *session;
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, "h2_conn_process start");
if (!workers) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02911)
"workers not initialized");
return APR_EGENERAL;
}
session = h2_session_rcreate(r, config, workers);
if (!session) {
return APR_EGENERAL;
}
return h2_session_process(session);
}
apr_status_t h2_conn_main(conn_rec *c)
{
h2_config *config = h2_config_get(c);
h2_session *session;
apr_status_t status;
ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, c, "h2_conn_main start");
if (!workers) {
ap_log_cerror(APLOG_MARK, APLOG_ERR, 0, c, APLOGNO(02912)
"workers not initialized");
return APR_EGENERAL;
}
session = h2_session_create(c, config, workers);
if (!session) {
return APR_EGENERAL;
}
if (!h2_is_acceptable_connection(c, 1)) {
nghttp2_submit_goaway(session->ngh2, NGHTTP2_FLAG_NONE, 0,
NGHTTP2_INADEQUATE_SECURITY, NULL, 0);
}
status = h2_session_process(session);
/* Make sure this connection gets closed properly. */
c->keepalive = AP_CONN_CLOSE;
if (c->cs) {
c->cs->state = CONN_STATE_WRITE_COMPLETION;
}
return status;
}
apr_status_t h2_session_process(h2_session *session)
{
apr_status_t status = APR_SUCCESS;
int rv = 0;
apr_interval_time_t wait_micros = 0;
static const int MAX_WAIT_MICROS = 200 * 1000;
/* Start talking to the client. Apart from protocol meta data,
* we mainly will see new http/2 streams opened by the client, which
* basically are http requests we need to dispatch.
*
* There will be bursts of new streams, to be served concurrently,
* followed by long pauses of no activity.
*
* Since the purpose of http/2 is to allow siumultaneous streams, we
* need to dispatch the handling of each stream into a separate worker
* thread, keeping this thread open for sending responses back as
* soon as they arrive.
* At the same time, we need to continue reading new frames from
* our client, which may be meta (WINDOWS_UPDATEs, PING, SETTINGS) or
* new streams.
*
* As long as we have streams open in this session, we cannot really rest
* since there are two conditions to wait on: 1. new data from the client,
* 2. new data from the open streams to send back.
*
* Only when we have no more streams open, can we do a blocking read
* on our connection.
*
* TODO: implement graceful GO_AWAY after configurable idle time
*/
ap_update_child_status_from_conn(session->c->sbh, SERVER_BUSY_READ,
session->c);
if (APLOGctrace2(session->c)) {
ap_filter_t *filter = session->c->input_filters;
while (filter) {
ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c,
"h2_conn(%ld), has connection filter %s",
session->id, filter->frec->name);
filter = filter->next;
}
}
status = h2_session_start(session, &rv);
ap_log_cerror(APLOG_MARK, APLOG_DEBUG, status, session->c,
"h2_session(%ld): starting on %s:%d", session->id,
session->c->base_server->defn_name,
session->c->local_addr->port);
if (status != APR_SUCCESS) {
h2_session_abort(session, status, rv);
h2_session_destroy(session);
return status;
}
while (!h2_session_is_done(session)) {
int have_written = 0;
int have_read = 0;
int got_streams;
status = h2_session_write(session, wait_micros);
if (status == APR_SUCCESS) {
have_written = 1;
wait_micros = 0;
}
else if (status == APR_EAGAIN) {
/* nop */
}
else if (status == APR_TIMEUP) {
wait_micros *= 2;
if (wait_micros > MAX_WAIT_MICROS) {
wait_micros = MAX_WAIT_MICROS;
}
}
else {
ap_log_cerror( APLOG_MARK, APLOG_DEBUG, status, session->c,
"h2_session(%ld): writing, terminating",
session->id);
h2_session_abort(session, status, 0);
break;
}
/* We would like to do blocking reads as often as possible as they
* are more efficient in regard to server resources.
* We can do them under the following circumstances:
* - we have no open streams and therefore have nothing to write
* - we have just started the session and are waiting for the first
* two frames to come in. There will always be at least 2 frames as
* * h2 will send SETTINGS and SETTINGS-ACK
* * h2c will count the header settings as one frame and we
* submit our settings and need the ACK.
*/
got_streams = !h2_stream_set_is_empty(session->streams);
status = h2_session_read(session,
(!got_streams
|| session->frames_received <= 1)?
APR_BLOCK_READ : APR_NONBLOCK_READ);
switch (status) {
case APR_SUCCESS: /* successful read, reset our idle timers */
have_read = 1;
wait_micros = 0;
break;
case APR_EAGAIN: /* non-blocking read, nothing there */
break;
case APR_EBADF: /* connection is not there any more */
case APR_EOF:
case APR_ECONNABORTED:
case APR_ECONNRESET:
case APR_TIMEUP: /* blocked read, timed out */
ap_log_cerror( APLOG_MARK, APLOG_DEBUG, status, session->c,
"h2_session(%ld): reading",
session->id);
h2_session_abort(session, status, 0);
break;
default:
ap_log_cerror( APLOG_MARK, APLOG_INFO, status, session->c,
APLOGNO(02950)
"h2_session(%ld): error reading, terminating",
session->id);
h2_session_abort(session, status, 0);
break;
}
if (!have_read && !have_written
&& !h2_stream_set_is_empty(session->streams)) {
/* Nothing to read or write, we have streams, but
* the have no data yet ready to be delivered. Slowly
* back off to give others a chance to do their work.
*/
if (wait_micros == 0) {
wait_micros = 10;
}
}
}
ap_log_cerror( APLOG_MARK, APLOG_DEBUG, status, session->c,
"h2_session(%ld): done", session->id);
ap_update_child_status_from_conn(session->c->sbh, SERVER_CLOSING,
session->c);
h2_session_close(session);
h2_session_destroy(session);
return DONE;
}
static void fix_event_conn(conn_rec *c, conn_rec *master);
/*
* We would like to create the connection more lightweight like
* slave connections in 2.5-DEV. But we get 500 responses on long
* cgi tests in modules/h2.t as the script parsing seems to see an
* EOF from the cgi before anything is sent.
*
conn_rec *h2_conn_create(conn_rec *master, apr_pool_t *pool)
{
conn_rec *c = (conn_rec *) apr_palloc(pool, sizeof(conn_rec));
memcpy(c, master, sizeof(conn_rec));
c->id = (master->id & (long)pool);
c->slaves = NULL;
c->master = master;
c->input_filters = NULL;
c->output_filters = NULL;
c->pool = pool;
return c;
}
*/
conn_rec *h2_conn_create(conn_rec *master, apr_pool_t *pool)
{
apr_socket_t *socket;
conn_rec *c;
AP_DEBUG_ASSERT(master);
/* CAVEAT: it seems necessary to setup the conn_rec in the master
* connection thread. Other attempts crashed.
* HOWEVER: we setup the connection using the pools and other items
* from the master connection, since we do not want to allocate
* lots of resources here.
* Lets allocated pools and everything else when we actually start
* working on this new connection.
*/
/* Not sure about the scoreboard handle. Reusing the one from the main
* connection could make sense, is not really correct, but we cannot
* easily create new handles for our worker threads either.
* TODO
*/
socket = ap_get_module_config(master->conn_config, &core_module);
c = ap_run_create_connection(pool, master->base_server,
socket,
master->id^((long)pool),
master->sbh,
master->bucket_alloc);
if (c == NULL) {
ap_log_perror(APLOG_MARK, APLOG_ERR, APR_ENOMEM, pool,
APLOGNO(02913) "h2_task: creating conn");
return NULL;
}
return c;
}
apr_status_t h2_conn_setup(h2_task_env *env, struct h2_worker *worker)
{
conn_rec *master = env->mplx->c;
ap_log_perror(APLOG_MARK, APLOG_TRACE3, 0, env->pool,
"h2_conn(%ld): created from master", master->id);
/* Ok, we are just about to start processing the connection and
* the worker is calling us to setup all necessary resources.
* We can borrow some from the worker itself and some we do as
* sub-resources from it, so that we get a nice reuse of
* pools.
*/
env->c.pool = env->pool;
env->c.bucket_alloc = h2_worker_get_bucket_alloc(worker);
env->c.current_thread = h2_worker_get_thread(worker);
env->c.conn_config = ap_create_conn_config(env->pool);
env->c.notes = apr_table_make(env->pool, 5);
ap_set_module_config(env->c.conn_config, &core_module,
h2_worker_get_socket(worker));
/* If we serve http:// requests over a TLS connection, we do
* not want any mod_ssl vars to be visible.
*/
if (ssl_module && (!env->scheme || strcmp("http", env->scheme))) {
/* See #19, there is a range of SSL variables to be gotten from
* the main connection that should be available in request handlers
*/
void *sslcfg = ap_get_module_config(master->conn_config, ssl_module);
if (sslcfg) {
ap_set_module_config(env->c.conn_config, ssl_module, sslcfg);
}
}
/* This works for mpm_worker so far. Other mpm modules have
* different needs, unfortunately. The most interesting one
* being mpm_event...
*/
switch (h2_conn_mpm_type()) {
case H2_MPM_WORKER:
/* all fine */
break;
case H2_MPM_EVENT:
fix_event_conn(&env->c, master);
break;
default:
/* fingers crossed */
break;
}
/* TODO: we simulate that we had already a request on this connection.
* This keeps the mod_ssl SNI vs. Host name matcher from answering
* 400 Bad Request
* when names do not match. We prefer a predictable 421 status.
*/
env->c.keepalives = 1;
return APR_SUCCESS;
}
apr_status_t h2_conn_post(conn_rec *c, h2_worker *worker)
{
(void)worker;
/* be sure no one messes with this any more */
memset(c, 0, sizeof(*c));
return APR_SUCCESS;
}
apr_status_t h2_conn_process(conn_rec *c, apr_socket_t *socket)
{
AP_DEBUG_ASSERT(c);
c->clogging_input_filters = 1;
ap_process_connection(c, socket);
return APR_SUCCESS;
}
/* This is an internal mpm event.c struct which is disguised
* as a conn_state_t so that mpm_event can have special connection
* state information without changing the struct seen on the outside.
*
* For our task connections we need to create a new beast of this type
* and fill it with enough meaningful things that mpm_event reads and
* starts processing out task request.
*/
typedef struct event_conn_state_t event_conn_state_t;
struct event_conn_state_t {
/** APR_RING of expiration timeouts */
APR_RING_ENTRY(event_conn_state_t) timeout_list;
/** the expiration time of the next keepalive timeout */
apr_time_t expiration_time;
/** connection record this struct refers to */
conn_rec *c;
/** request record (if any) this struct refers to */
request_rec *r;
/** is the current conn_rec suspended? (disassociated with
* a particular MPM thread; for suspend_/resume_connection
* hooks)
*/
int suspended;
/** memory pool to allocate from */
apr_pool_t *p;
/** bucket allocator */
apr_bucket_alloc_t *bucket_alloc;
/** poll file descriptor information */
apr_pollfd_t pfd;
/** public parts of the connection state */
conn_state_t pub;
};
APR_RING_HEAD(timeout_head_t, event_conn_state_t);
static void fix_event_conn(conn_rec *c, conn_rec *master)
{
event_conn_state_t *master_cs = ap_get_module_config(master->conn_config,
h2_conn_mpm_module());
event_conn_state_t *cs = apr_pcalloc(c->pool, sizeof(event_conn_state_t));
cs->bucket_alloc = apr_bucket_alloc_create(c->pool);
ap_set_module_config(c->conn_config, h2_conn_mpm_module(), cs);
cs->c = c;
cs->r = NULL;
cs->p = master_cs->p;
cs->pfd = master_cs->pfd;
cs->pub = master_cs->pub;
cs->pub.state = CONN_STATE_READ_REQUEST_LINE;
c->cs = &(cs->pub);
}
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