nghttp2/src/shrpx_http2_session.h

297 lines
9.0 KiB
C++

/*
* nghttp2 - HTTP/2 C Library
*
* Copyright (c) 2012 Tatsuhiro Tsujikawa
*
* 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.
*/
#ifndef SHRPX_HTTP2_SESSION_H
#define SHRPX_HTTP2_SESSION_H
#include "shrpx.h"
#include <unordered_set>
#include <memory>
#include <openssl/ssl.h>
#include <ev.h>
#include <nghttp2/nghttp2.h>
#include "llhttp.h"
#include "shrpx_connection.h"
#include "buffer.h"
#include "template.h"
using namespace nghttp2;
namespace shrpx {
class Http2DownstreamConnection;
class Worker;
class Downstream;
struct DownstreamAddrGroup;
struct DownstreamAddr;
struct DNSQuery;
struct StreamData {
StreamData *dlnext, *dlprev;
Http2DownstreamConnection *dconn;
};
enum class FreelistZone {
// Http2Session object is not linked in any freelist.
NONE,
// Http2Session object is linked in address scope
// http2_extra_freelist.
EXTRA,
// Http2Session object is about to be deleted, and it does not
// belong to any linked list.
GONE
};
enum class Http2SessionState {
// Disconnected
DISCONNECTED,
// Connecting proxy and making CONNECT request
PROXY_CONNECTING,
// Tunnel is established with proxy
PROXY_CONNECTED,
// Establishing tunnel is failed
PROXY_FAILED,
// Connecting to downstream and/or performing SSL/TLS handshake
CONNECTING,
// Connected to downstream
CONNECTED,
// Connection is started to fail
CONNECT_FAILING,
// Resolving host name
RESOLVING_NAME,
};
enum class ConnectionCheck {
// Connection checking is not required
NONE,
// Connection checking is required
REQUIRED,
// Connection checking has been started
STARTED,
};
class Http2Session {
public:
Http2Session(struct ev_loop *loop, SSL_CTX *ssl_ctx, Worker *worker,
const std::shared_ptr<DownstreamAddrGroup> &group,
DownstreamAddr *addr);
~Http2Session();
// If hard is true, all pending requests are abandoned and
// associated ClientHandlers will be deleted.
int disconnect(bool hard = false);
int initiate_connection();
int resolve_name();
void add_downstream_connection(Http2DownstreamConnection *dconn);
void remove_downstream_connection(Http2DownstreamConnection *dconn);
void remove_stream_data(StreamData *sd);
int submit_request(Http2DownstreamConnection *dconn, const nghttp2_nv *nva,
size_t nvlen, const nghttp2_data_provider *data_prd);
int submit_rst_stream(int32_t stream_id, uint32_t error_code);
int terminate_session(uint32_t error_code);
nghttp2_session *get_session() const;
int resume_data(Http2DownstreamConnection *dconn);
int connection_made();
int do_read();
int do_write();
int on_read(const uint8_t *data, size_t datalen);
int on_write();
int connected();
int read_clear();
int write_clear();
int tls_handshake();
int read_tls();
int write_tls();
// This is a special write function which just stop write event
// watcher.
int write_void();
int downstream_read_proxy(const uint8_t *data, size_t datalen);
int downstream_connect_proxy();
int downstream_read(const uint8_t *data, size_t datalen);
int downstream_write();
int noop();
int read_noop(const uint8_t *data, size_t datalen);
int write_noop();
void signal_write();
struct ev_loop *get_loop() const;
ev_io *get_wev();
Http2SessionState get_state() const;
void set_state(Http2SessionState state);
void start_settings_timer();
void stop_settings_timer();
SSL *get_ssl() const;
int consume(int32_t stream_id, size_t len);
// Returns true if request can be issued on downstream connection.
bool can_push_request(const Downstream *downstream) const;
// Initiates the connection checking if downstream connection has
// been established and connection checking is required.
void start_checking_connection();
// Resets connection check timer to timeout |t|. After timeout, we
// require connection checking. If connection checking is already
// enabled, this timeout is for PING ACK timeout.
void reset_connection_check_timer(ev_tstamp t);
void reset_connection_check_timer_if_not_checking();
// Signals that connection is alive. Internally
// reset_connection_check_timer() is called.
void connection_alive();
// Change connection check state.
void set_connection_check_state(ConnectionCheck state);
ConnectionCheck get_connection_check_state() const;
bool should_hard_fail() const;
void submit_pending_requests();
DownstreamAddr *get_addr() const;
const std::shared_ptr<DownstreamAddrGroup> &get_downstream_addr_group() const;
int handle_downstream_push_promise(Downstream *downstream,
int32_t promised_stream_id);
int handle_downstream_push_promise_complete(Downstream *downstream,
Downstream *promised_downstream);
// Returns number of downstream connections, including pushed
// streams.
size_t get_num_dconns() const;
// Adds to group scope http2_avail_freelist.
void add_to_avail_freelist();
// Adds to address scope http2_extra_freelist.
void add_to_extra_freelist();
// Removes this object from any freelist. If this object is not
// linked from any freelist, this function does nothing.
void remove_from_freelist();
// Removes this object form any freelist, and marks this object as
// not schedulable.
void exclude_from_scheduling();
// Returns true if the maximum concurrency is reached. In other
// words, the number of currently participated streams in this
// session is equal or greater than the max concurrent streams limit
// advertised by server. If |extra| is nonzero, it is added to the
// number of current concurrent streams when comparing against
// server initiated concurrency limit.
bool max_concurrency_reached(size_t extra = 0) const;
DefaultMemchunks *get_request_buf();
void on_timeout();
// This is called periodically using ev_prepare watcher, and if
// group_ is retired (backend has been replaced), send GOAWAY to
// shutdown the connection.
void check_retire();
// Returns address used to connect to backend. Could be nullptr.
const Address *get_raddr() const;
// This is called when SETTINGS frame without ACK flag set is
// received.
void on_settings_received(const nghttp2_frame *frame);
bool get_allow_connect_proto() const;
using ReadBuf = Buffer<8_k>;
Http2Session *dlnext, *dlprev;
private:
Connection conn_;
DefaultMemchunks wb_;
ev_timer settings_timer_;
// This timer has 2 purpose: when it first timeout, set
// connection_check_state_ = ConnectionCheck::REQUIRED. After
// connection check has started, this timer is started again and
// traps PING ACK timeout.
ev_timer connchk_timer_;
// timer to initiate connection. usually, this fires immediately.
ev_timer initiate_connection_timer_;
ev_prepare prep_;
DList<Http2DownstreamConnection> dconns_;
DList<StreamData> streams_;
std::function<int(Http2Session &)> read_, write_;
std::function<int(Http2Session &, const uint8_t *, size_t)> on_read_;
std::function<int(Http2Session &)> on_write_;
// Used to parse the response from HTTP proxy
std::unique_ptr<llhttp_t> proxy_htp_;
Worker *worker_;
// NULL if no TLS is configured
SSL_CTX *ssl_ctx_;
std::shared_ptr<DownstreamAddrGroup> group_;
// Address of remote endpoint
DownstreamAddr *addr_;
nghttp2_session *session_;
// Actual remote address used to contact backend. This is initially
// nullptr, and may point to either &addr_->addr,
// resolved_addr_.get(), or HTTP proxy's address structure.
const Address *raddr_;
// Resolved IP address if dns parameter is used
std::unique_ptr<Address> resolved_addr_;
std::unique_ptr<DNSQuery> dns_query_;
Http2SessionState state_;
ConnectionCheck connection_check_state_;
FreelistZone freelist_zone_;
// true if SETTINGS without ACK is received from peer.
bool settings_recved_;
// true if peer enables RFC 8441 CONNECT protocol.
bool allow_connect_proto_;
};
nghttp2_session_callbacks *create_http2_downstream_callbacks();
} // namespace shrpx
#endif // SHRPX_HTTP2_SESSION_H