/*
* Copyright (C) 2007 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/**
* @file
*
* Hyper Text Transfer Protocol (HTTP)
*
*/
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <strings.h>
#include <byteswap.h>
#include <errno.h>
#include <assert.h>
#include <gpxe/uri.h>
#include <gpxe/refcnt.h>
#include <gpxe/iobuf.h>
#include <gpxe/xfer.h>
#include <gpxe/open.h>
#include <gpxe/socket.h>
#include <gpxe/tcpip.h>
#include <gpxe/process.h>
#include <gpxe/linebuf.h>
#include <gpxe/features.h>
#include <gpxe/http.h>
FEATURE ( "HTTP", DHCP_EB_FEATURE_HTTP, 1 );
/** HTTP receive state */
enum http_rx_state {
HTTP_RX_RESPONSE = 0,
HTTP_RX_HEADER,
HTTP_RX_DATA,
HTTP_RX_DEAD,
};
/**
* An HTTP request
*
*/
struct http_request {
/** Reference count */
struct refcnt refcnt;
/** Data transfer interface */
struct xfer_interface xfer;
/** URI being fetched */
struct uri *uri;
/** Transport layer interface */
struct xfer_interface socket;
/** TX process */
struct process process;
/** HTTP response code */
unsigned int response;
/** HTTP Content-Length */
size_t content_length;
/** Received length */
size_t rx_len;
/** RX state */
enum http_rx_state rx_state;
/** Line buffer for received header lines */
struct line_buffer linebuf;
};
/**
* Free HTTP request
*
* @v refcnt Reference counter
*/
static void http_free ( struct refcnt *refcnt ) {
struct http_request *http =
container_of ( refcnt, struct http_request, refcnt );
uri_put ( http->uri );
empty_line_buffer ( &http->linebuf );
free ( http );
};
/**
* Mark HTTP request as complete
*
* @v http HTTP request
* @v rc Return status code
*/
static void http_done ( struct http_request *http, int rc ) {
/* Prevent further processing of any current packet */
http->rx_state = HTTP_RX_DEAD;
/* If we had a Content-Length, and the received content length
* isn't correct, flag an error
*/
if ( http->content_length &&
( http->content_length != http->rx_len ) ) {
DBGC ( http, "HTTP %p incorrect length %zd, should be %zd\n",
http, http->rx_len, http->content_length );
rc = -EIO;
}
/* Remove process */
process_del ( &http->process );
/* Close all data transfer interfaces */
xfer_nullify ( &http->socket );
xfer_close ( &http->socket, rc );
xfer_nullify ( &http->xfer );
xfer_close ( &http->xfer, rc );
}
/**
* Convert HTTP response code to return status code
*
* @v response HTTP response code
* @ret rc Return status code
*/
static int http_response_to_rc ( unsigned int response ) {
switch ( response ) {
case 200:
return 0;
case 404:
return -ENOENT;
case 403:
return -EPERM;
default:
return -EIO;
}
}
/**
* Handle HTTP response
*
* @v http HTTP request
* @v response HTTP response
* @ret rc Return status code
*/
static int http_rx_response ( struct http_request *http, char *response ) {
char *spc;
int rc;
DBGC ( http, "HTTP %p response \"%s\"\n", http, response );
/* Check response starts with "HTTP/" */
if ( strncmp ( response, "HTTP/", 5 ) != 0 )
return -EIO;
/* Locate and check response code */
spc = strchr ( response, ' ' );
if ( ! spc )
return -EIO;
http->response = strtoul ( spc, NULL, 10 );
if ( ( rc = http_response_to_rc ( http->response ) ) != 0 )
return rc;
/* Move to received headers */
http->rx_state = HTTP_RX_HEADER;
return 0;
}
/**
* Handle HTTP Content-Length header
*
* @v http HTTP request
* @v value HTTP header value
* @ret rc Return status code
*/
static int http_rx_content_length ( struct http_request *http,
const char *value ) {
char *endp;
http->content_length = strtoul ( value, &endp, 10 );
if ( *endp != '\0' ) {
DBGC ( http, "HTTP %p invalid Content-Length \"%s\"\n",
http, value );
return -EIO;
}
/* Use seek() to notify recipient of filesize */
xfer_seek ( &http->xfer, http->content_length, SEEK_SET );
xfer_seek ( &http->xfer, 0, SEEK_SET );
return 0;
}
/** An HTTP header handler */
struct http_header_handler {
/** Name (e.g. "Content-Length") */
const char *header;
/** Handle received header
*
* @v http HTTP request
* @v value HTTP header value
* @ret rc Return status code
*
* If an error is returned, the download will be aborted.
*/
int ( * rx ) ( struct http_request *http, const char *value );
};
/** List of HTTP header handlers */
static struct http_header_handler http_header_handlers[] = {
{
.header = "Content-Length",
.rx = http_rx_content_length,
},
{ NULL, NULL }
};
/**
* Handle HTTP header
*
* @v http HTTP request
* @v header HTTP header
* @ret rc Return status code
*/
static int http_rx_header ( struct http_request *http, char *header ) {
struct http_header_handler *handler;
char *separator;
char *value;
int rc;
/* An empty header line marks the transition to the data phase */
if ( ! header[0] ) {
DBGC ( http, "HTTP %p start of data\n", http );
empty_line_buffer ( &http->linebuf );
http->rx_state = HTTP_RX_DATA;
return 0;
}
DBGC ( http, "HTTP %p header \"%s\"\n", http, header );
/* Split header at the ": " */
separator = strstr ( header, ": " );
if ( ! separator ) {
DBGC ( http, "HTTP %p malformed header\n", http );
return -EIO;
}
*separator = '\0';
value = ( separator + 2 );
/* Hand off to header handler, if one exists */
for ( handler = http_header_handlers ; handler->header ; handler++ ) {
if ( strcasecmp ( header, handler->header ) == 0 ) {
if ( ( rc = handler->rx ( http, value ) ) != 0 )
return rc;
break;
}
}
return 0;
}
/** An HTTP line-based data handler */
struct http_line_handler {
/** Handle line
*
* @v http HTTP request
* @v line Line to handle
* @ret rc Return status code
*/
int ( * rx ) ( struct http_request *http, char *line );
};
/** List of HTTP line-based data handlers */
static struct http_line_handler http_line_handlers[] = {
[HTTP_RX_RESPONSE] = { .rx = http_rx_response },
[HTTP_RX_HEADER] = { .rx = http_rx_header },
};
/**
* Handle new data arriving via HTTP connection in the data phase
*
* @v http HTTP request
* @v iobuf I/O buffer
* @ret rc Return status code
*/
static int http_rx_data ( struct http_request *http,
struct io_buffer *iobuf ) {
int rc;
/* Update received length */
http->rx_len += iob_len ( iobuf );
/* Hand off data buffer */
if ( ( rc = xfer_deliver_iob ( &http->xfer, iobuf ) ) != 0 )
return rc;
/* If we have reached the content-length, stop now */
if ( http->content_length &&
( http->rx_len >= http->content_length ) ) {
http_done ( http, 0 );
}
return 0;
}
/**
* Handle new data arriving via HTTP connection
*
* @v socket Transport layer interface
* @v iobuf I/O buffer
* @v meta Data transfer metadata, or NULL
* @ret rc Return status code
*/
static int http_socket_deliver_iob ( struct xfer_interface *socket,
struct io_buffer *iobuf,
struct xfer_metadata *meta __unused ) {
struct http_request *http =
container_of ( socket, struct http_request, socket );
struct http_line_handler *lh;
char *line;
ssize_t len;
int rc = 0;
while ( iob_len ( iobuf ) ) {
switch ( http->rx_state ) {
case HTTP_RX_DEAD:
/* Do no further processing */
goto done;
case HTTP_RX_DATA:
/* Once we're into the data phase, just fill
* the data buffer
*/
rc = http_rx_data ( http, iobuf );
iobuf = NULL;
goto done;
case HTTP_RX_RESPONSE:
case HTTP_RX_HEADER:
/* In the other phases, buffer and process a
* line at a time
*/
len = line_buffer ( &http->linebuf, iobuf->data,
iob_len ( iobuf ) );
if ( len < 0 ) {
rc = len;
DBGC ( http, "HTTP %p could not buffer line: "
"%s\n", http, strerror ( rc ) );
goto done;
}
iob_pull ( iobuf, len );
line = buffered_line ( &http->linebuf );
if ( line ) {
lh = &http_line_handlers[http->rx_state];
if ( ( rc = lh->rx ( http, line ) ) != 0 )
goto done;
}
break;
default:
assert ( 0 );
break;
}
}
done:
if ( rc )
http_done ( http, rc );
free_iob ( iobuf );
return rc;
}
/**
* HTTP process
*
* @v process Process
*/
static void http_step ( struct process *process ) {
struct http_request *http =
container_of ( process, struct http_request, process );
const char *path = http->uri->path;
const char *host = http->uri->host;
const char *query = http->uri->query;
int rc;
if ( xfer_window ( &http->socket ) ) {
process_del ( &http->process );
if ( ( rc = xfer_printf ( &http->socket,
"GET %s%s%s HTTP/1.1\r\n"
"User-Agent: gPXE/" VERSION "\r\n"
"Host: %s\r\n"
"\r\n",
( path ? path : "/" ),
( query ? "?" : "" ),
( query ? query : "" ),
host ) ) != 0 ) {
http_done ( http, rc );
}
}
}
/**
* HTTP connection closed by network stack
*
* @v socket Transport layer interface
* @v rc Reason for close
*/
static void http_socket_close ( struct xfer_interface *socket, int rc ) {
struct http_request *http =
container_of ( socket, struct http_request, socket );
DBGC ( http, "HTTP %p socket closed: %s\n",
http, strerror ( rc ) );
http_done ( http, rc );
}
/** HTTP socket operations */
static struct xfer_interface_operations http_socket_operations = {
.close = http_socket_close,
.vredirect = xfer_vopen,
.seek = ignore_xfer_seek,
.window = unlimited_xfer_window,
.alloc_iob = default_xfer_alloc_iob,
.deliver_iob = http_socket_deliver_iob,
.deliver_raw = xfer_deliver_as_iob,
};
/**
* Close HTTP data transfer interface
*
* @v xfer Data transfer interface
* @v rc Reason for close
*/
static void http_xfer_close ( struct xfer_interface *xfer, int rc ) {
struct http_request *http =
container_of ( xfer, struct http_request, xfer );
DBGC ( http, "HTTP %p interface closed: %s\n",
http, strerror ( rc ) );
http_done ( http, rc );
}
/** HTTP data transfer interface operations */
static struct xfer_interface_operations http_xfer_operations = {
.close = http_xfer_close,
.vredirect = ignore_xfer_vredirect,
.seek = ignore_xfer_seek,
.window = unlimited_xfer_window,
.alloc_iob = default_xfer_alloc_iob,
.deliver_iob = xfer_deliver_as_raw,
.deliver_raw = ignore_xfer_deliver_raw,
};
/**
* Initiate an HTTP connection, with optional filter
*
* @v xfer Data transfer interface
* @v uri Uniform Resource Identifier
* @v default_port Default port number
* @v filter Filter to apply to socket, or NULL
* @ret rc Return status code
*/
int http_open_filter ( struct xfer_interface *xfer, struct uri *uri,
unsigned int default_port,
int ( * filter ) ( struct xfer_interface *xfer,
struct xfer_interface **next ) ) {
struct http_request *http;
struct sockaddr_tcpip server;
struct xfer_interface *socket;
int rc;
/* Sanity checks */
if ( ! uri->host )
return -EINVAL;
/* Allocate and populate HTTP structure */
http = zalloc ( sizeof ( *http ) );
if ( ! http )
return -ENOMEM;
http->refcnt.free = http_free;
xfer_init ( &http->xfer, &http_xfer_operations, &http->refcnt );
http->uri = uri_get ( uri );
xfer_init ( &http->socket, &http_socket_operations, &http->refcnt );
process_init ( &http->process, http_step, &http->refcnt );
/* Open socket */
memset ( &server, 0, sizeof ( server ) );
server.st_port = htons ( uri_port ( http->uri, default_port ) );
socket = &http->socket;
if ( filter ) {
if ( ( rc = filter ( socket, &socket ) ) != 0 )
goto err;
}
if ( ( rc = xfer_open_named_socket ( socket, SOCK_STREAM,
( struct sockaddr * ) &server,
uri->host, NULL ) ) != 0 )
goto err;
/* Attach to parent interface, mortalise self, and return */
xfer_plug_plug ( &http->xfer, xfer );
ref_put ( &http->refcnt );
return 0;
err:
DBGC ( http, "HTTP %p could not create request: %s\n",
http, strerror ( rc ) );
http_done ( http, rc );
ref_put ( &http->refcnt );
return rc;
}
/**
* Initiate an HTTP connection
*
* @v xfer Data transfer interface
* @v uri Uniform Resource Identifier
* @ret rc Return status code
*/
static int http_open ( struct xfer_interface *xfer, struct uri *uri ) {
return http_open_filter ( xfer, uri, HTTP_PORT, NULL );
}
/** HTTP URI opener */
struct uri_opener http_uri_opener __uri_opener = {
.scheme = "http",
.open = http_open,
};
