httpconn.c File Reference

Hyper Text Transfer Protocol (HTTP) connection management. More...

#include <stdlib.h>
#include <string.h>
#include <strings.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>

Go to the source code of this file.

Macros
#define	HTTP_CONN_EXPIRY   ( 10 * TICKS_PER_SEC )
	HTTP pooled connection expiry time.

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
	FILE_SECBOOT (PERMITTED)
static	LIST_HEAD (http_connection_pool)
	HTTP connection pool.
static struct http_scheme *	http_scheme (struct uri *uri)
	Identify HTTP scheme.
static void	http_conn_free (struct refcnt *refcnt)
	Free HTTP connection.
static void	http_conn_close (struct http_connection *conn, int rc)
	Close HTTP connection.
static void	http_conn_expired (struct pooled_connection *pool)
	Disconnect idle HTTP connection.
static int	http_conn_socket_deliver (struct http_connection *conn, struct io_buffer *iobuf, struct xfer_metadata *meta)
	Receive data from transport layer interface.
static void	http_conn_socket_close (struct http_connection *conn, int rc)
	Close HTTP connection transport layer interface.
static void	http_conn_xfer_recycle (struct http_connection *conn)
	Recycle this connection after closing.
static void	http_conn_xfer_close (struct http_connection *conn, int rc)
	Close HTTP connection data transfer interface.
int	http_connect (struct interface *xfer, struct uri *uri)
	Connect to an HTTP server.

Variables
static struct interface_operation	http_conn_socket_operations []
	HTTP connection socket interface operations.
static struct interface_descriptor	http_conn_socket_desc
	HTTP connection socket interface descriptor.
static struct interface_operation	http_conn_xfer_operations []
	HTTP connection data transfer interface operations.
static struct interface_descriptor	http_conn_xfer_desc
	HTTP connection data transfer interface descriptor.

Detailed Description

Hyper Text Transfer Protocol (HTTP) connection management.

Definition in file httpconn.c.

Macro Definition Documentation

HTTP_CONN_EXPIRY

#define HTTP_CONN_EXPIRY   ( 10 * TICKS_PER_SEC )

HTTP pooled connection expiry time.

Definition at line 48 of file httpconn.c.

Referenced by http_conn_xfer_close().

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

FILE_SECBOOT()

FILE_SECBOOT

(

PERMITTED

)

LIST_HEAD()

LIST_HEAD ( http_connection_pool )

static

HTTP connection pool.

http_scheme()

struct http_scheme * http_scheme ( struct uri * uri )

static

Identify HTTP scheme.

Parameters

uri

URI

Return values

scheme

HTTP scheme, or NULL

Definition at line 59 of file httpconn.c.

                                                            {
        struct http_scheme *scheme;
 
        /* Sanity check */
        if ( ! uri->scheme )
                return NULL;
 
        /* Identify scheme */
        for_each_table_entry ( scheme, HTTP_SCHEMES ) {
                if ( strcasecmp ( uri->scheme, scheme->name ) == 0 )
                        return scheme;
        }
 
        return NULL;
}

References for_each_table_entry, HTTP_SCHEMES, http_scheme::name, NULL, uri::scheme, and strcasecmp().

Referenced by http_connect().

http_conn_free()

void http_conn_free ( struct refcnt * refcnt )

static

Free HTTP connection.

Parameters

refcnt

Reference count

Definition at line 80 of file httpconn.c.

                                                     {
        struct http_connection *conn =
                container_of ( refcnt, struct http_connection, refcnt );
 
        /* Free connection */
        uri_put ( conn->uri );
        free ( conn );
}

References container_of, free, http_connection::uri, and uri_put().

Referenced by http_connect().

http_conn_close()

void http_conn_close ( struct http_connection * conn, int rc )

static

Close HTTP connection.

Parameters

conn	HTTP connection
rc	Reason for close

Definition at line 95 of file httpconn.c.

                                                                     {
 
        /* 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 ) );
        }
}

References DBGC, DBGC2, uri::host, intf_shutdown(), http_scheme::name, http_connection::pool, pool_del(), rc, http_connection::scheme, http_connection::socket, strerror(), http_connection::uri, and http_connection::xfer.

Referenced by http_conn_expired(), http_conn_socket_close(), http_conn_xfer_close(), and http_connect().

http_conn_expired()

void http_conn_expired ( struct pooled_connection * pool )

static

Disconnect idle HTTP connection.

Parameters

pool	Pooled connection

Definition at line 118 of file httpconn.c.

                                                                 {
        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 */ );
}

References container_of, http_conn_close(), and pool.

Referenced by http_connect().

http_conn_socket_deliver()

int http_conn_socket_deliver ( struct http_connection * conn, struct io_buffer * iobuf, struct xfer_metadata * meta )

static

Receive data from transport layer interface.

Parameters

http	HTTP connection
iobuf	I/O buffer
meta	Transfer metadata

Return values

rc	Return status code

Definition at line 134 of file httpconn.c.

                                                                   {
 
        /* Mark connection as alive */
        pool_alive ( &conn->pool );
 
        /* Pass on to data transfer interface */
        return xfer_deliver ( &conn->xfer, iobuf, meta );
}

References meta, http_connection::pool, http_connection::xfer, and xfer_deliver().

http_conn_socket_close()

void http_conn_socket_close ( struct http_connection * conn, int rc )

static

Close HTTP connection transport layer interface.

Parameters

http	HTTP connection
rc	Reason for close

Definition at line 151 of file httpconn.c.

                                                                            {
 
        /* 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 );
}

References http_conn_close(), http_connection::pool, pool_reopen(), rc, and http_connection::xfer.

http_conn_xfer_recycle()

void http_conn_xfer_recycle ( struct http_connection * conn )

static

Recycle this connection after closing.

Parameters

http	HTTP connection

Definition at line 170 of file httpconn.c.

                                                                    {
 
        /* Mark connection as recyclable */
        pool_recyclable ( &conn->pool );
        DBGC2 ( conn, "HTTPCONN %p keepalive enabled\n", conn );
}

References DBGC2, and http_connection::pool.

http_conn_xfer_close()

void http_conn_xfer_close ( struct http_connection * conn, int rc )

static

Close HTTP connection data transfer interface.

Parameters

conn	HTTP connection
rc	Reason for close

Definition at line 183 of file httpconn.c.

                                                                          {
 
        /* 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 );
}

References DBGC2, uri::host, http_conn_close(), HTTP_CONN_EXPIRY, intf_restart(), http_scheme::name, http_connection::pool, pool_add(), rc, http_connection::scheme, http_connection::uri, and http_connection::xfer.

http_connect()

int http_connect	(	struct interface *	xfer,
		struct uri *	uri )

Connect to an HTTP server.

Parameters

xfer	Data transfer interface
uri	Connection URI

Return values

rc	Return status code

HTTP connections are pooled. The caller should be prepared to receive a pool_reopen() message.

Definition at line 237 of file httpconn.c.

                                                             {
        struct http_connection *conn;
        struct http_scheme *scheme;
        struct sockaddr_tcpip server;
        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 );
        if ( ( rc = xfer_open_named_socket ( &conn->socket, SOCK_STREAM,
                                             ( struct sockaddr * ) &server,
                                             uri->host, NULL ) ) != 0 )
                goto err_open;
 
        /* Add filter, if any */
        if ( scheme->filter && ( ( rc = scheme->filter ( conn ) ) != 0 ) )
                goto err_filter;
 
        /* 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_filter:
 err_open:
        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;
}

References assert, DBGC2, EINVAL, ENOMEM, ENOTSUP, http_scheme::filter, uri::host, htons, http_conn_close(), http_conn_expired(), http_conn_free(), http_conn_socket_desc, http_conn_xfer_desc, http_scheme(), intf_init(), intf_plug_plug(), list_for_each_entry_reverse, memset(), http_scheme::name, NULL, http_connection::pool, pool, pool_del(), http_scheme::port, port, rc, ref_init, ref_put, http_connection::refcnt, http_connection::scheme, SOCK_STREAM, http_connection::socket, sockaddr_tcpip::st_port, strcmp(), strerror(), http_connection::uri, uri_get(), uri_port(), http_connection::xfer, xfer_open_named_socket(), and zalloc().

Referenced by http_open(), and http_reopen().

Variable Documentation

http_conn_socket_operations

struct interface_operation http_conn_socket_operations[]

static

Initial value:

= {
        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 operations.

Definition at line 202 of file httpconn.c.

                                                                  {
        INTF_OP ( xfer_deliver, struct http_connection *,
                  http_conn_socket_deliver ),
        INTF_OP ( intf_close, struct http_connection *,
                  http_conn_socket_close ),
};

http_conn_socket_desc

struct interface_descriptor http_conn_socket_desc

static

Initial value:

=
        INTF_DESC_PASSTHRU ( struct http_connection, socket,
                             http_conn_socket_operations, xfer )

HTTP connection socket interface descriptor.

Definition at line 210 of file httpconn.c.

Referenced by http_connect().

http_conn_xfer_operations

struct interface_operation http_conn_xfer_operations[]

static

Initial value:

= {
        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 operations.

Definition at line 215 of file httpconn.c.

                                                                {
        INTF_OP ( pool_recycle, struct http_connection *,
                  http_conn_xfer_recycle ),
        INTF_OP ( intf_close, struct http_connection *,
                  http_conn_xfer_close ),
};

http_conn_xfer_desc

struct interface_descriptor http_conn_xfer_desc

static

Initial value:

=
        INTF_DESC_PASSTHRU ( struct http_connection, xfer,
                             http_conn_xfer_operations, socket )

HTTP connection data transfer interface descriptor.

Definition at line 223 of file httpconn.c.

Referenced by http_connect().