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Diffstat (limited to 'contrib/syslinux-4.02/gpxe/src/net/icmp.c')
-rw-r--r--contrib/syslinux-4.02/gpxe/src/net/icmp.c103
1 files changed, 103 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/gpxe/src/net/icmp.c b/contrib/syslinux-4.02/gpxe/src/net/icmp.c
new file mode 100644
index 0000000..749c345
--- /dev/null
+++ b/contrib/syslinux-4.02/gpxe/src/net/icmp.c
@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2009 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 );
+
+#include <string.h>
+#include <errno.h>
+#include <gpxe/iobuf.h>
+#include <gpxe/in.h>
+#include <gpxe/tcpip.h>
+#include <gpxe/icmp.h>
+
+/** @file
+ *
+ * ICMP protocol
+ *
+ */
+
+struct tcpip_protocol icmp_protocol __tcpip_protocol;
+
+/**
+ * Process a received packet
+ *
+ * @v iobuf I/O buffer
+ * @v st_src Partially-filled source address
+ * @v st_dest Partially-filled destination address
+ * @v pshdr_csum Pseudo-header checksum
+ * @ret rc Return status code
+ */
+static int icmp_rx ( struct io_buffer *iobuf, struct sockaddr_tcpip *st_src,
+ struct sockaddr_tcpip *st_dest,
+ uint16_t pshdr_csum __unused ) {
+ struct icmp_header *icmp = iobuf->data;
+ size_t len = iob_len ( iobuf );
+ unsigned int csum;
+ int rc;
+
+ /* Sanity check */
+ if ( len < sizeof ( *icmp ) ) {
+ DBG ( "ICMP packet too short at %zd bytes (min %zd bytes)\n",
+ len, sizeof ( *icmp ) );
+ rc = -EINVAL;
+ goto done;
+ }
+
+ /* Verify checksum */
+ csum = tcpip_chksum ( icmp, len );
+ if ( csum != 0 ) {
+ DBG ( "ICMP checksum incorrect (is %04x, should be 0000)\n",
+ csum );
+ DBG_HD ( icmp, len );
+ rc = -EINVAL;
+ goto done;
+ }
+
+ /* We respond only to pings */
+ if ( icmp->type != ICMP_ECHO_REQUEST ) {
+ DBG ( "ICMP ignoring type %d\n", icmp->type );
+ rc = 0;
+ goto done;
+ }
+
+ DBG ( "ICMP responding to ping\n" );
+
+ /* Change type to response and recalculate checksum */
+ icmp->type = ICMP_ECHO_RESPONSE;
+ icmp->chksum = 0;
+ icmp->chksum = tcpip_chksum ( icmp, len );
+
+ /* Transmit the response */
+ if ( ( rc = tcpip_tx ( iob_disown ( iobuf ), &icmp_protocol, st_dest,
+ st_src, NULL, NULL ) ) != 0 ) {
+ DBG ( "ICMP could not transmit ping response: %s\n",
+ strerror ( rc ) );
+ goto done;
+ }
+
+ done:
+ free_iob ( iobuf );
+ return rc;
+}
+
+/** ICMP TCP/IP protocol */
+struct tcpip_protocol icmp_protocol __tcpip_protocol = {
+ .name = "ICMP",
+ .rx = icmp_rx,
+ .tcpip_proto = IP_ICMP,
+};