/*
* Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
* You can also choose to distribute this program under the terms of
* the Unmodified Binary Distribution Licence (as given in the file
* COPYING.UBDL), provided that you have satisfied its requirements.
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
/**
* @file
*
* Hyper Text Transfer Protocol (HTTP) connection management
*
*/
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <byteswap.h>
#include <ipxe/tcpip.h>
#include <ipxe/uri.h>
#include <ipxe/timer.h>
#include <ipxe/xfer.h>
#include <ipxe/open.h>
#include <ipxe/pool.h>
#include <ipxe/http.h>
/** HTTP pooled connection expiry time */
#define HTTP_CONN_EXPIRY ( 10 * TICKS_PER_SEC )
/** HTTP connection pool */
static LIST_HEAD ( http_connection_pool );
/**
* Identify HTTP scheme
*
* @v uri URI
* @ret scheme HTTP scheme, or NULL
*/
static struct http_scheme * http_scheme ( struct uri *uri ) {
struct http_scheme *scheme;
/* Sanity check */
if ( ! uri->scheme )
return NULL;
/* Identify scheme */
for_each_table_entry ( scheme, HTTP_SCHEMES ) {
if ( strcmp ( uri->scheme, scheme->name ) == 0 )
return scheme;
}
return NULL;
}
/**
* Free HTTP connection
*
* @v refcnt Reference count
*/
static void http_conn_free ( struct refcnt *refcnt ) {
struct http_connection *conn =
container_of ( refcnt, struct http_connection, refcnt );
/* Free connection */
uri_put ( conn->uri );
free ( conn );
}
/**
* Close HTTP connection
*
* @v conn HTTP connection
* @v rc Reason for close
*/
static void http_conn_close ( struct http_connection *conn, int rc ) {
/* Remove from connection pool, if applicable */
pool_del ( &conn->pool );
/* Shut down interfaces */
intf_shutdown ( &conn->socket, rc );
intf_shutdown ( &conn->xfer, rc );
if ( rc == 0 ) {
DBGC2 ( conn, "HTTPCONN %p closed %s://%s\n",
conn, conn->scheme->name, conn->uri->host );
} else {
DBGC ( conn, "HTTPCONN %p closed %s://%s: %s\n",
conn, conn->scheme->name, conn->uri->host,
strerror ( rc ) );
}
}
/**
* Disconnect idle HTTP connection
*
* @v pool Pooled connection
*/
static void http_conn_expired ( struct pooled_connection *pool ) {
struct http_connection *conn =
container_of ( pool, struct http_connection, pool );
/* Close connection */
http_conn_close ( conn, 0 /* Not an error to close idle connection */ );
}
/**
* Receive data from transport layer interface
*
* @v http HTTP connection
* @v iobuf I/O buffer
* @v meta Transfer metadata
* @ret rc Return status code
*/
static int http_conn_socket_deliver ( struct http_connection *conn,
struct io_buffer *iobuf,
struct xfer_metadata *meta ) {
/* Mark connection as alive */
pool_alive ( &conn->pool );
/* Pass on to data transfer interface */
return xfer_deliver ( &conn->xfer, iobuf, meta );
}
/**
* Close HTTP connection transport layer interface
*
* @v http HTTP connection
* @v rc Reason for close
*/
static void http_conn_socket_close ( struct http_connection *conn, int rc ) {
/* If we are reopenable (i.e. we are a recycled connection
* from the connection pool, and we have received no data from
* the underlying socket since we were pooled), then suggest
* that the client should reopen the connection.
*/
if ( pool_is_reopenable ( &conn->pool ) )
pool_reopen ( &conn->xfer );
/* Close the connection */
http_conn_close ( conn, rc );
}
/**
* Recycle this connection after closing
*
* @v http HTTP connection
*/
static void http_conn_xfer_recycle ( struct http_connection *conn ) {
/* Mark connection as recyclable */
pool_recyclable ( &conn->pool );
DBGC2 ( conn, "HTTPCONN %p keepalive enabled\n", conn );
}
/**
* Close HTTP connection data transfer interface
*
* @v conn HTTP connection
* @v rc Reason for close
*/
static void http_conn_xfer_close ( struct http_connection *conn, int rc ) {
/* Add to the connection pool if keepalive is enabled and no
* error occurred.
*/
if ( ( rc == 0 ) && pool_is_recyclable ( &conn->pool ) ) {
intf_restart ( &conn->xfer, rc );
pool_add ( &conn->pool, &http_connection_pool,
HTTP_CONN_EXPIRY );
DBGC2 ( conn, "HTTPCONN %p pooled %s://%s\n",
conn, conn->scheme->name, conn->uri->host );
return;
}
/* Otherwise, close the connection */
http_conn_close ( conn, rc );
}
/** HTTP connection socket interface operations */
static struct interface_operation http_conn_socket_operations[] = {
INTF_OP ( xfer_deliver, struct http_connection *,
http_conn_socket_deliver ),
INTF_OP ( intf_close, struct http_connection *,
http_conn_socket_close ),
};
/** HTTP connection socket interface descriptor */
static struct interface_descriptor http_conn_socket_desc =
INTF_DESC_PASSTHRU ( struct http_connection, socket,
http_conn_socket_operations, xfer );
/** HTTP connection data transfer interface operations */
static struct interface_operation http_conn_xfer_operations[] = {
INTF_OP ( pool_recycle, struct http_connection *,
http_conn_xfer_recycle ),
INTF_OP ( intf_close, struct http_connection *,
http_conn_xfer_close ),
};
/** HTTP connection data transfer interface descriptor */
static struct interface_descriptor http_conn_xfer_desc =
INTF_DESC_PASSTHRU ( struct http_connection, xfer,
http_conn_xfer_operations, socket );
/**
* Connect to an HTTP server
*
* @v xfer Data transfer interface
* @v uri Connection URI
* @ret rc Return status code
*
* HTTP connections are pooled. The caller should be prepared to
* receive a pool_reopen() message.
*/
int http_connect ( struct interface *xfer, struct uri *uri ) {
struct http_connection *conn;
struct http_scheme *scheme;
struct sockaddr_tcpip server;
struct interface *socket;
unsigned int port;
int rc;
/* Identify scheme */
scheme = http_scheme ( uri );
if ( ! scheme )
return -ENOTSUP;
/* Sanity check */
if ( ! uri->host )
return -EINVAL;
/* Identify port */
port = uri_port ( uri, scheme->port );
/* Look for a reusable connection in the pool. Reuse the most
* recent connection in order to accommodate authentication
* schemes that break the stateless nature of HTTP and rely on
* the same connection being reused for authentication
* responses.
*/
list_for_each_entry_reverse ( conn, &http_connection_pool, pool.list ) {
/* Sanity checks */
assert ( conn->uri != NULL );
assert ( conn->uri->host != NULL );
/* Reuse connection, if possible */
if ( ( scheme == conn->scheme ) &&
( strcmp ( uri->host, conn->uri->host ) == 0 ) &&
( port == uri_port ( conn->uri, scheme->port ) ) ) {
/* Remove from connection pool, stop timer,
* attach to parent interface, and return.
*/
pool_del ( &conn->pool );
intf_plug_plug ( &conn->xfer, xfer );
DBGC2 ( conn, "HTTPCONN %p reused %s://%s:%d\n", conn,
conn->scheme->name, conn->uri->host, port );
return 0;
}
}
/* Allocate and initialise structure */
conn = zalloc ( sizeof ( *conn ) );
if ( ! conn ) {
rc = -ENOMEM;
goto err_alloc;
}
ref_init ( &conn->refcnt, http_conn_free );
conn->uri = uri_get ( uri );
conn->scheme = scheme;
intf_init ( &conn->socket, &http_conn_socket_desc, &conn->refcnt );
intf_init ( &conn->xfer, &http_conn_xfer_desc, &conn->refcnt );
pool_init ( &conn->pool, http_conn_expired, &conn->refcnt );
/* Open socket */
memset ( &server, 0, sizeof ( server ) );
server.st_port = htons ( port );
socket = &conn->socket;
if ( scheme->filter &&
( ( rc = scheme->filter ( socket, uri->host, &socket ) ) != 0 ) )
goto err_filter;
if ( ( rc = xfer_open_named_socket ( socket, SOCK_STREAM,
( struct sockaddr * ) &server,
uri->host, NULL ) ) != 0 )
goto err_open;
/* Attach to parent interface, mortalise self, and return */
intf_plug_plug ( &conn->xfer, xfer );
ref_put ( &conn->refcnt );
DBGC2 ( conn, "HTTPCONN %p created %s://%s:%d\n", conn,
conn->scheme->name, conn->uri->host, port );
return 0;
err_open:
err_filter:
DBGC2 ( conn, "HTTPCONN %p could not create %s://%s:%d: %s\n", conn,
conn->scheme->name, conn->uri->host, port, strerror ( rc ) );
http_conn_close ( conn, rc );
ref_put ( &conn->refcnt );
err_alloc:
return rc;
}
