/*
* 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_LICENCE ( GPL2_OR_LATER );
/**
* @file
*
* Hyper Text Transfer Protocol (HTTP) core functionality
*
*/
#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 <ipxe/uri.h>
#include <ipxe/refcnt.h>
#include <ipxe/iobuf.h>
#include <ipxe/xfer.h>
#include <ipxe/open.h>
#include <ipxe/socket.h>
#include <ipxe/tcpip.h>
#include <ipxe/process.h>
#include <ipxe/linebuf.h>
#include <ipxe/base64.h>
#include <ipxe/blockdev.h>
#include <ipxe/acpi.h>
#include <ipxe/http.h>
/** Block size used for HTTP block device request */
#define HTTP_BLKSIZE 512
/** HTTP flags */
enum http_flags {
/** Request is waiting to be transmitted */
HTTP_TX_PENDING = 0x0001,
/** Fetch header only */
HTTP_HEAD_ONLY = 0x0002,
/** Keep connection alive */
HTTP_KEEPALIVE = 0x0004,
};
/** HTTP receive state */
enum http_rx_state {
HTTP_RX_RESPONSE = 0,
HTTP_RX_HEADER,
HTTP_RX_CHUNK_LEN,
HTTP_RX_DATA,
HTTP_RX_TRAILER,
HTTP_RX_IDLE,
HTTP_RX_DEAD,
};
/**
* An HTTP request
*
*/
struct http_request {
/** Reference count */
struct refcnt refcnt;
/** Data transfer interface */
struct interface xfer;
/** Partial transfer interface */
struct interface partial;
/** URI being fetched */
struct uri *uri;
/** Transport layer interface */
struct interface socket;
/** Flags */
unsigned int flags;
/** Starting offset of partial transfer (if applicable) */
size_t partial_start;
/** Length of partial transfer (if applicable) */
size_t partial_len;
/** TX process */
struct process process;
/** RX state */
enum http_rx_state rx_state;
/** Received length */
size_t rx_len;
/** Length remaining (or 0 if unknown) */
size_t remaining;
/** HTTP is using Transfer-Encoding: chunked */
int chunked;
/** Current chunk length remaining (if applicable) */
size_t chunk_remaining;
/** Line buffer for received header lines */
struct line_buffer linebuf;
/** Receive data buffer (if applicable) */
userptr_t rx_buffer;
};
/**
* 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 );
};
/**
* Close HTTP request
*
* @v http HTTP request
* @v rc Return status code
*/
static void http_close ( 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->remaining != 0 ) {
DBGC ( http, "HTTP %p incorrect length %zd, should be %zd\n",
http, http->rx_len, ( http->rx_len + http->remaining ) );
if ( rc == 0 )
rc = -EIO;
}
/* Remove process */
process_del ( &http->process );
/* Close all data transfer interfaces */
intf_shutdown ( &http->socket, rc );
intf_shutdown ( &http->partial, rc );
intf_shutdown ( &http->xfer, rc );
}
/**
* Mark HTTP request as completed successfully
*
* @v http HTTP request
*/
static void http_done ( struct http_request *http ) {
/* If we had a Content-Length, and the received content length
* isn't correct, force an error
*/
if ( http->remaining != 0 ) {
http_close ( http, -EIO );
return;
}
/* Enter idle state */
http->rx_state = HTTP_RX_IDLE;
http->rx_len = 0;
assert ( http->remaining == 0 );
assert ( http->chunked == 0 );
assert ( http->chunk_remaining == 0 );
/* Close partial transfer interface */
intf_restart ( &http->partial, 0 );
/* Close everything unless we are keeping the connection alive */
if ( ! ( http->flags & HTTP_KEEPALIVE ) )
http_close ( http, 0 );
}
/**
* 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:
case 206:
case 301:
case 302:
case 303:
return 0;
case 404:
return -ENOENT;
case 403:
return -EPERM;
case 401:
return -EACCES;
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;
unsigned int code;
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;
code = strtoul ( spc, NULL, 10 );
if ( ( rc = http_response_to_rc ( code ) ) != 0 )
return rc;
/* Move to received headers */
http->rx_state = HTTP_RX_HEADER;
return 0;
}
/**
* Handle HTTP Location header
*
* @v http HTTP request
* @v value HTTP header value
* @ret rc Return status code
*/
static int http_rx_location ( struct http_request *http, const char *value ) {
int rc;
/* Redirect to new location */
DBGC ( http, "HTTP %p redirecting to %s\n", http, value );
if ( ( rc = xfer_redirect ( &http->xfer, LOCATION_URI_STRING,
value ) ) != 0 ) {
DBGC ( http, "HTTP %p could not redirect: %s\n",
http, strerror ( rc ) );
return rc;
}
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 ) {
struct block_device_capacity capacity;
size_t content_len;
char *endp;
/* Parse content length */
content_len = strtoul ( value, &endp, 10 );
if ( *endp != '\0' ) {
DBGC ( http, "HTTP %p invalid Content-Length \"%s\"\n",
http, value );
return -EIO;
}
/* If we already have an expected content length, and this
* isn't it, then complain
*/
if ( http->remaining && ( http->remaining != content_len ) ) {
DBGC ( http, "HTTP %p incorrect Content-Length %zd (expected "
"%zd)\n", http, content_len, http->remaining );
return -EIO;
}
if ( ! ( http->flags & HTTP_HEAD_ONLY ) )
http->remaining = content_len;
/* Use seek() to notify recipient of filesize */
xfer_seek ( &http->xfer, http->remaining );
xfer_seek ( &http->xfer, 0 );
/* Report block device capacity if applicable */
if ( http->flags & HTTP_HEAD_ONLY ) {
capacity.blocks = ( content_len / HTTP_BLKSIZE );
capacity.blksize = HTTP_BLKSIZE;
capacity.max_count = -1U;
block_capacity ( &http->partial, &capacity );
}
return 0;
}
/**
* Handle HTTP Transfer-Encoding header
*
* @v http HTTP request
* @v value HTTP header value
* @ret rc Return status code
*/
static int http_rx_transfer_encoding ( struct http_request *http,
const char *value ) {
if ( strcmp ( value, "chunked" ) == 0 ) {
/* Mark connection as using chunked transfer encoding */
http->chunked = 1;
}
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 = "Location",
.rx = http_rx_location,
},
{
.header = "Content-Length",
.rx = http_rx_content_length,
},
{
.header = "Transfer-Encoding",
.rx = http_rx_transfer_encoding,
},
{ 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 end of this phase */
if ( ! header[0] ) {
empty_line_buffer ( &http->linebuf );
if ( ( http->rx_state == HTTP_RX_HEADER ) &&
( ! ( http->flags & HTTP_HEAD_ONLY ) ) ) {
DBGC ( http, "HTTP %p start of data\n", http );
http->rx_state = ( http->chunked ?
HTTP_RX_CHUNK_LEN : HTTP_RX_DATA );
return 0;
} else {
DBGC ( http, "HTTP %p end of trailer\n", http );
http_done ( http );
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;
}
/**
* Handle HTTP chunk length
*
* @v http HTTP request
* @v length HTTP chunk length
* @ret rc Return status code
*/
static int http_rx_chunk_len ( struct http_request *http, char *length ) {
char *endp;
/* Skip blank lines between chunks */
if ( length[0] == '\0' )
return 0;
/* Parse chunk length */
http->chunk_remaining = strtoul ( length, &endp, 16 );
if ( *endp != '\0' ) {
DBGC ( http, "HTTP %p invalid chunk length \"%s\"\n",
http, length );
return -EIO;
}
/* Terminate chunked encoding if applicable */
if ( http->chunk_remaining == 0 ) {
DBGC ( http, "HTTP %p end of chunks\n", http );
http->chunked = 0;
http->rx_state = HTTP_RX_TRAILER;
return 0;
}
/* Use seek() to notify recipient of new filesize */
DBGC ( http, "HTTP %p start of chunk of length %zd\n",
http, http->chunk_remaining );
xfer_seek ( &http->xfer, ( http->rx_len + http->chunk_remaining ) );
xfer_seek ( &http->xfer, http->rx_len );
/* Start receiving data */
http->rx_state = HTTP_RX_DATA;
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 },
[HTTP_RX_CHUNK_LEN] = { .rx = http_rx_chunk_len },
[HTTP_RX_TRAILER] = { .rx = http_rx_header },
};
/**
* Handle new data arriving via HTTP connection
*
* @v http HTTP request
* @v iobuf I/O buffer
* @v meta Data transfer metadata
* @ret rc Return status code
*/
static int http_socket_deliver ( struct http_request *http,
struct io_buffer *iobuf,
struct xfer_metadata *meta __unused ) {
struct http_line_handler *lh;
char *line;
size_t data_len;
ssize_t line_len;
int rc = 0;
while ( iobuf && iob_len ( iobuf ) ) {
switch ( http->rx_state ) {
case HTTP_RX_IDLE:
/* Receiving any data in this state is an error */
DBGC ( http, "HTTP %p received %zd bytes while %s\n",
http, iob_len ( iobuf ),
( ( http->rx_state == HTTP_RX_IDLE ) ?
"idle" : "dead" ) );
rc = -EPROTO;
goto done;
case HTTP_RX_DEAD:
/* Do no further processing */
goto done;
case HTTP_RX_DATA:
/* Pass received data to caller */
data_len = iob_len ( iobuf );
if ( http->chunk_remaining &&
( http->chunk_remaining < data_len ) ) {
data_len = http->chunk_remaining;
}
if ( http->remaining &&
( http->remaining < data_len ) ) {
data_len = http->remaining;
}
if ( http->rx_buffer != UNULL ) {
/* Copy to partial transfer buffer */
copy_to_user ( http->rx_buffer, http->rx_len,
iobuf->data, data_len );
iob_pull ( iobuf, data_len );
} else if ( data_len < iob_len ( iobuf ) ) {
/* Deliver partial buffer as raw data */
rc = xfer_deliver_raw ( &http->xfer,
iobuf->data, data_len );
iob_pull ( iobuf, data_len );
if ( rc != 0 )
goto done;
} else {
/* Deliver whole I/O buffer */
if ( ( rc = xfer_deliver_iob ( &http->xfer,
iob_disown ( iobuf ) ) ) != 0 )
goto done;
}
http->rx_len += data_len;
if ( http->chunk_remaining ) {
http->chunk_remaining -= data_len;
if ( http->chunk_remaining == 0 )
http->rx_state = HTTP_RX_CHUNK_LEN;
}
if ( http->remaining ) {
http->remaining -= data_len;
if ( ( http->remaining == 0 ) &&
( http->rx_state == HTTP_RX_DATA ) ) {
http_done ( http );
}
}
break;
case HTTP_RX_RESPONSE:
case HTTP_RX_HEADER:
case HTTP_RX_CHUNK_LEN:
case HTTP_RX_TRAILER:
/* In the other phases, buffer and process a
* line at a time
*/
line_len = line_buffer ( &http->linebuf, iobuf->data,
iob_len ( iobuf ) );
if ( line_len < 0 ) {
rc = line_len;
DBGC ( http, "HTTP %p could not buffer line: "
"%s\n", http, strerror ( rc ) );
goto done;
}
iob_pull ( iobuf, line_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_close ( http, rc );
free_iob ( iobuf );
return rc;
}
/**
* Check HTTP socket flow control window
*
* @v http HTTP request
* @ret len Length of window
*/
static size_t http_socket_window ( struct http_request *http __unused ) {
/* Window is always open. This is to prevent TCP from
* stalling if our parent window is not currently open.
*/
return ( ~( ( size_t ) 0 ) );
}
/**
* HTTP process
*
* @v http HTTP request
*/
static void http_step ( struct http_request *http ) {
const char *host = http->uri->host;
const char *user = http->uri->user;
const char *password =
( http->uri->password ? http->uri->password : "" );
size_t user_pw_len = ( user ? ( strlen ( user ) + 1 /* ":" */ +
strlen ( password ) ) : 0 );
size_t user_pw_base64_len = base64_encoded_len ( user_pw_len );
uint8_t user_pw[ user_pw_len + 1 /* NUL */ ];
char user_pw_base64[ user_pw_base64_len + 1 /* NUL */ ];
int rc;
int request_len = unparse_uri ( NULL, 0, http->uri,
URI_PATH_BIT | URI_QUERY_BIT );
char request[ request_len + 1 /* NUL */ ];
char range[48]; /* Enough for two 64-bit integers in decimal */
int partial;
/* Do nothing if we have already transmitted the request */
if ( ! ( http->flags & HTTP_TX_PENDING ) )
return;
/* Do nothing until socket is ready */
if ( ! xfer_window ( &http->socket ) )
return;
/* Construct path?query request */
unparse_uri ( request, sizeof ( request ), http->uri,
URI_PATH_BIT | URI_QUERY_BIT );
/* Construct authorisation, if applicable */
if ( user ) {
/* Make "user:password" string from decoded fields */
snprintf ( ( ( char * ) user_pw ), sizeof ( user_pw ),
"%s:%s", user, password );
/* Base64-encode the "user:password" string */
base64_encode ( user_pw, user_pw_len, user_pw_base64 );
}
/* Force a HEAD request if we have nowhere to send any received data */
if ( ( xfer_window ( &http->xfer ) == 0 ) &&
( http->rx_buffer == UNULL ) ) {
http->flags |= ( HTTP_HEAD_ONLY | HTTP_KEEPALIVE );
}
/* Determine type of request */
partial = ( http->partial_len != 0 );
snprintf ( range, sizeof ( range ), "%zd-%zd", http->partial_start,
( http->partial_start + http->partial_len - 1 ) );
/* Mark request as transmitted */
http->flags &= ~HTTP_TX_PENDING;
/* Send GET request */
if ( ( rc = xfer_printf ( &http->socket,
"%s %s%s HTTP/1.1\r\n"
"User-Agent: iPXE/" VERSION "\r\n"
"Host: %s%s%s\r\n"
"%s%s%s%s%s%s%s"
"\r\n",
( ( http->flags & HTTP_HEAD_ONLY ) ?
"HEAD" : "GET" ),
( http->uri->path ? "" : "/" ),
request, host,
( http->uri->port ?
":" : "" ),
( http->uri->port ?
http->uri->port : "" ),
( ( http->flags & HTTP_KEEPALIVE ) ?
"Connection: Keep-Alive\r\n" : "" ),
( partial ? "Range: bytes=" : "" ),
( partial ? range : "" ),
( partial ? "\r\n" : "" ),
( user ?
"Authorization: Basic " : "" ),
( user ? user_pw_base64 : "" ),
( user ? "\r\n" : "" ) ) ) != 0 ) {
http_close ( http, rc );
}
}
/**
* Check HTTP data transfer flow control window
*
* @v http HTTP request
* @ret len Length of window
*/
static size_t http_xfer_window ( struct http_request *http ) {
/* New block commands may be issued only when we are idle */
return ( ( http->rx_state == HTTP_RX_IDLE ) ? 1 : 0 );
}
/**
* Initiate HTTP partial read
*
* @v http HTTP request
* @v partial Partial transfer interface
* @v offset Starting offset
* @v buffer Data buffer
* @v len Length
* @ret rc Return status code
*/
static int http_partial_read ( struct http_request *http,
struct interface *partial,
size_t offset, userptr_t buffer, size_t len ) {
/* Sanity check */
if ( http_xfer_window ( http ) == 0 )
return -EBUSY;
/* Initialise partial transfer parameters */
http->rx_buffer = buffer;
http->partial_start = offset;
http->partial_len = len;
http->remaining = len;
/* Schedule request */
http->rx_state = HTTP_RX_RESPONSE;
http->flags = ( HTTP_TX_PENDING | HTTP_KEEPALIVE );
if ( ! len )
http->flags |= HTTP_HEAD_ONLY;
process_add ( &http->process );
/* Attach to parent interface and return */
intf_plug_plug ( &http->partial, partial );
return 0;
}
/**
* Issue HTTP block device read
*
* @v http HTTP request
* @v block Block data interface
* @v lba Starting logical block address
* @v count Number of blocks to transfer
* @v buffer Data buffer
* @v len Length of data buffer
* @ret rc Return status code
*/
static int http_block_read ( struct http_request *http,
struct interface *block,
uint64_t lba, unsigned int count,
userptr_t buffer, size_t len __unused ) {
return http_partial_read ( http, block, ( lba * HTTP_BLKSIZE ),
buffer, ( count * HTTP_BLKSIZE ) );
}
/**
* Read HTTP block device capacity
*
* @v http HTTP request
* @v block Block data interface
* @ret rc Return status code
*/
static int http_block_read_capacity ( struct http_request *http,
struct interface *block ) {
return http_partial_read ( http, block, 0, 0, 0 );
}
/**
* Describe HTTP device in an ACPI table
*
* @v http HTTP request
* @v acpi ACPI table
* @v len Length of ACPI table
* @ret rc Return status code
*/
static int http_acpi_describe ( struct http_request *http,
struct acpi_description_header *acpi,
size_t len ) {
DBGC ( http, "HTTP %p cannot yet describe device in an ACPI table\n",
http );
( void ) acpi;
( void ) len;
return 0;
}
/** HTTP socket interface operations */
static struct interface_operation http_socket_operations[] = {
INTF_OP ( xfer_window, struct http_request *, http_socket_window ),
INTF_OP ( xfer_deliver, struct http_request *, http_socket_deliver ),
INTF_OP ( xfer_window_changed, struct http_request *, http_step ),
INTF_OP ( intf_close, struct http_request *, http_close ),
};
/** HTTP socket interface descriptor */
static struct interface_descriptor http_socket_desc =
INTF_DESC_PASSTHRU ( struct http_request, socket,
http_socket_operations, xfer );
/** HTTP partial transfer interface operations */
static struct interface_operation http_partial_operations[] = {
INTF_OP ( intf_close, struct http_request *, http_close ),
};
/** HTTP partial transfer interface descriptor */
static struct interface_descriptor http_partial_desc =
INTF_DESC ( struct http_request, partial, http_partial_operations );
/** HTTP data transfer interface operations */
static struct interface_operation http_xfer_operations[] = {
INTF_OP ( xfer_window, struct http_request *, http_xfer_window ),
INTF_OP ( block_read, struct http_request *, http_block_read ),
INTF_OP ( block_read_capacity, struct http_request *,
http_block_read_capacity ),
INTF_OP ( intf_close, struct http_request *, http_close ),
INTF_OP ( acpi_describe, struct http_request *, http_acpi_describe ),
};
/** HTTP data transfer interface descriptor */
static struct interface_descriptor http_xfer_desc =
INTF_DESC_PASSTHRU ( struct http_request, xfer,
http_xfer_operations, socket );
/** HTTP process descriptor */
static struct process_descriptor http_process_desc =
PROC_DESC_ONCE ( struct http_request, process, http_step );
/**
* 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 interface *xfer, struct uri *uri,
unsigned int default_port,
int ( * filter ) ( struct interface *xfer,
const char *name,
struct interface **next ) ) {
struct http_request *http;
struct sockaddr_tcpip server;
struct interface *socket;
int rc;
/* Sanity checks */
if ( ! uri->host )
return -EINVAL;
/* Allocate and populate HTTP structure */
http = zalloc ( sizeof ( *http ) );
if ( ! http )
return -ENOMEM;
ref_init ( &http->refcnt, http_free );
intf_init ( &http->xfer, &http_xfer_desc, &http->refcnt );
intf_init ( &http->partial, &http_partial_desc, &http->refcnt );
http->uri = uri_get ( uri );
intf_init ( &http->socket, &http_socket_desc, &http->refcnt );
process_init ( &http->process, &http_process_desc, &http->refcnt );
http->flags = HTTP_TX_PENDING;
/* 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, uri->host, &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 */
intf_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_close ( http, rc );
ref_put ( &http->refcnt );
return rc;
}
