[pxe] Split out platform-independent portions of cachedhcp.c

Split out the portions of cachedhcp.c that can be shared between BIOS
and UEFI (both of which can provide a buffer containing a previously
obtained DHCP packet, and neither of which provide a means to
determine the length of this DHCP packet).

Signed-off-by: Michael Brown <mcb30@ipxe.org>

2 files changed, 76 insertions, 179 deletions

diff --git a/src/arch/x86/core/cachedhcp.c b/src/arch/x86/core/cachedhcp.c
deleted file mode 100644
index dffafe3..0000000
--- a/src/arch/x86/core/cachedhcp.c
+++ /dev/null
@@ -1,179 +0,0 @@
-/*
- * Copyright (C) 2013 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 );
-
-#include <stdint.h>
-#include <stdlib.h>
-#include <ipxe/dhcppkt.h>
-#include <ipxe/init.h>
-#include <ipxe/netdevice.h>
-#include <realmode.h>
-#include <pxe_api.h>
-
-/** @file
- *
- * Cached DHCP packet
- *
- */
-
-/** Cached DHCPACK physical address
- *
- * This can be set by the prefix.
- */
-uint32_t __bss16 ( cached_dhcpack_phys );
-#define cached_dhcpack_phys __use_data16 ( cached_dhcpack_phys )
-
-/** Colour for debug messages */
-#define colour &cached_dhcpack_phys
-
-/** Cached DHCPACK */
-static struct dhcp_packet *cached_dhcpack;
-
-/**
- * Cached DHCPACK startup function
- *
- */
-static void cachedhcp_init ( void ) {
-	struct dhcp_packet *dhcppkt;
-	struct dhcp_packet *tmp;
-	struct dhcphdr *dhcphdr;
-	size_t max_len;
-	size_t len;
-
-	/* Do nothing if no cached DHCPACK is present */
-	if ( ! cached_dhcpack_phys ) {
-		DBGC ( colour, "CACHEDHCP found no cached DHCPACK\n" );
-		return;
-	}
-
-	/* No reliable way to determine length before parsing packet;
-	 * start by assuming maximum length permitted by PXE.
-	 */
-	max_len = sizeof ( BOOTPLAYER_t );
-
-	/* Allocate and populate DHCP packet */
-	dhcppkt = zalloc ( sizeof ( *dhcppkt ) + max_len );
-	if ( ! dhcppkt ) {
-		DBGC ( colour, "CACHEDHCP could not allocate copy\n" );
-		return;
-	}
-	dhcphdr = ( ( ( void * ) dhcppkt ) + sizeof ( *dhcppkt ) );
-	copy_from_user ( dhcphdr, phys_to_user ( cached_dhcpack_phys ), 0,
-			 max_len );
-	dhcppkt_init ( dhcppkt, dhcphdr, max_len );
-
-	/* Shrink packet to required length.  If reallocation fails,
-	 * just continue to use the original packet and waste the
-	 * unused space.
-	 */
-	len = dhcppkt_len ( dhcppkt );
-	assert ( len <= max_len );
-	tmp = realloc ( dhcppkt, ( sizeof ( *dhcppkt ) + len ) );
-	if ( tmp )
-		dhcppkt = tmp;
-
-	/* Reinitialise packet at new address */
-	dhcphdr = ( ( ( void * ) dhcppkt ) + sizeof ( *dhcppkt ) );
-	dhcppkt_init ( dhcppkt, dhcphdr, len );
-
-	/* Store as cached DHCPACK, and mark original copy as consumed */
-	DBGC ( colour, "CACHEDHCP found cached DHCPACK at %08x+%zx\n",
-	       cached_dhcpack_phys, len );
-	cached_dhcpack = dhcppkt;
-	cached_dhcpack_phys = 0;
-}
-
-/**
- * Cached DHCPACK startup function
- *
- */
-static void cachedhcp_startup ( void ) {
-
-	/* If cached DHCP packet was not claimed by any network device
-	 * during startup, then free it.
-	 */
-	if ( cached_dhcpack ) {
-		DBGC ( colour, "CACHEDHCP freeing unclaimed cached DHCPACK\n" );
-		dhcppkt_put ( cached_dhcpack );
-		cached_dhcpack = NULL;
-	}
-}
-
-/** Cached DHCPACK initialisation function */
-struct init_fn cachedhcp_init_fn __init_fn ( INIT_NORMAL ) = {
-	.initialise = cachedhcp_init,
-};
-
-/** Cached DHCPACK startup function */
-struct startup_fn cachedhcp_startup_fn __startup_fn ( STARTUP_LATE ) = {
-	.name = "cachedhcp",
-	.startup = cachedhcp_startup,
-};
-
-/**
- * Apply cached DHCPACK to network device, if applicable
- *
- * @v netdev		Network device
- * @ret rc		Return status code
- */
-static int cachedhcp_probe ( struct net_device *netdev ) {
-	struct ll_protocol *ll_protocol = netdev->ll_protocol;
-	int rc;
-
-	/* Do nothing unless we have a cached DHCPACK */
-	if ( ! cached_dhcpack )
-		return 0;
-
-	/* Do nothing unless cached DHCPACK's MAC address matches this
-	 * network device.
-	 */
-	if ( memcmp ( netdev->ll_addr, cached_dhcpack->dhcphdr->chaddr,
-		      ll_protocol->ll_addr_len ) != 0 ) {
-		DBGC ( colour, "CACHEDHCP cached DHCPACK does not match %s\n",
-		       netdev->name );
-		return 0;
-	}
-	DBGC ( colour, "CACHEDHCP cached DHCPACK is for %s\n", netdev->name );
-
-	/* Register as DHCP settings for this network device */
-	if ( ( rc = register_settings ( &cached_dhcpack->settings,
-					netdev_settings ( netdev ),
-					DHCP_SETTINGS_NAME ) ) != 0 ) {
-		DBGC ( colour, "CACHEDHCP could not register settings: %s\n",
-		       strerror ( rc ) );
-		return rc;
-	}
-
-	/* Claim cached DHCPACK */
-	dhcppkt_put ( cached_dhcpack );
-	cached_dhcpack = NULL;
-
-	return 0;
-}
-
-/** Cached DHCP packet network device driver */
-struct net_driver cachedhcp_driver __net_driver = {
-	.name = "cachedhcp",
-	.probe = cachedhcp_probe,
-};
diff --git a/src/arch/x86/interface/pcbios/bios_cachedhcp.c b/src/arch/x86/interface/pcbios/bios_cachedhcp.c
new file mode 100644
index 0000000..3d38699
--- /dev/null
+++ b/src/arch/x86/interface/pcbios/bios_cachedhcp.c
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2013 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 );
+
+#include <stdint.h>
+#include <ipxe/init.h>
+#include <ipxe/cachedhcp.h>
+#include <realmode.h>
+#include <pxe_api.h>
+
+/** @file
+ *
+ * Cached DHCP packet
+ *
+ */
+
+/** Cached DHCPACK physical address
+ *
+ * This can be set by the prefix.
+ */
+uint32_t __bss16 ( cached_dhcpack_phys );
+#define cached_dhcpack_phys __use_data16 ( cached_dhcpack_phys )
+
+/** Colour for debug messages */
+#define colour &cached_dhcpack_phys
+
+/**
+ * Cached DHCPACK initialisation function
+ *
+ */
+static void cachedhcp_init ( void ) {
+	int rc;
+
+	/* Do nothing if no cached DHCPACK is present */
+	if ( ! cached_dhcpack_phys ) {
+		DBGC ( colour, "CACHEDHCP found no cached DHCPACK\n" );
+		return;
+	}
+
+	/* Record cached DHCPACK */
+	if ( ( rc = cachedhcp_record ( phys_to_user ( cached_dhcpack_phys ),
+				       sizeof ( BOOTPLAYER_t ) ) ) != 0 ) {
+		DBGC ( colour, "CACHEDHCP could not record DHCPACK: %s\n",
+		       strerror ( rc ) );
+		return;
+	}
+
+	/* Mark as consumed */
+	cached_dhcpack_phys = 0;
+}
+
+/** Cached DHCPACK initialisation function */
+struct init_fn cachedhcp_init_fn __init_fn ( INIT_NORMAL ) = {
+	.initialise = cachedhcp_init,
+};