--- /dev/null
+/*
+ * Copyright (C) 2008 Stefan Hajnoczi <stefanha@gmail.com>.
+ *
+ * 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.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdio.h>
+#include <string.h>
+#include <byteswap.h>
+#include <ipxe/iobuf.h>
+#include <ipxe/in.h>
+#include <ipxe/if_arp.h>
+#include <ipxe/if_ether.h>
+#include <ipxe/ip.h>
+#include <ipxe/udp.h>
+#include <ipxe/netdevice.h>
+#include <ipxe/nap.h>
+#include <ipxe/gdbstub.h>
+#include <ipxe/gdbudp.h>
+
+/** @file
+ *
+ * GDB over UDP transport
+ *
+ */
+
+enum {
+ DEFAULT_PORT = 43770, /* UDP listen port */
+};
+
+struct gdb_transport udp_gdb_transport __gdb_transport;
+
+static struct net_device *netdev;
+static uint8_t dest_eth[ETH_ALEN];
+static struct sockaddr_in dest_addr;
+static struct sockaddr_in source_addr;
+
+static void gdbudp_ensure_netdev_open ( struct net_device *netdev ) {
+ /* The device may have been closed between breakpoints */
+ assert ( netdev );
+ netdev_open ( netdev );
+
+ /* Strictly speaking, we may need to close the device when leaving the interrupt handler */
+}
+
+static size_t gdbudp_recv ( char *buf, size_t len ) {
+ struct io_buffer *iob;
+ struct ethhdr *ethhdr;
+ struct arphdr *arphdr;
+ struct iphdr *iphdr;
+ struct udp_header *udphdr;
+ size_t payload_len;
+
+ gdbudp_ensure_netdev_open ( netdev );
+
+ for ( ; ; ) {
+ netdev_poll ( netdev );
+ while ( ( iob = netdev_rx_dequeue ( netdev ) ) != NULL ) {
+ /* Ethernet header */
+ if ( iob_len ( iob ) < sizeof ( *ethhdr ) ) {
+ goto bad_packet;
+ }
+ ethhdr = iob->data;
+ iob_pull ( iob, sizeof ( *ethhdr ) );
+
+ /* Handle ARP requests so the client can find our MAC */
+ if ( ethhdr->h_protocol == htons ( ETH_P_ARP ) ) {
+ arphdr = iob->data;
+ if ( iob_len ( iob ) < sizeof ( *arphdr ) + 2 * ( ETH_ALEN + sizeof ( struct in_addr ) ) ||
+ arphdr->ar_hrd != htons ( ARPHRD_ETHER ) ||
+ arphdr->ar_pro != htons ( ETH_P_IP ) ||
+ arphdr->ar_hln != ETH_ALEN ||
+ arphdr->ar_pln != sizeof ( struct in_addr ) ||
+ arphdr->ar_op != htons ( ARPOP_REQUEST ) ||
+ * ( uint32_t * ) arp_target_pa ( arphdr ) != source_addr.sin_addr.s_addr ) {
+ goto bad_packet;
+ }
+
+ /* Generate an ARP reply */
+ arphdr->ar_op = htons ( ARPOP_REPLY );
+ memswap ( arp_sender_pa ( arphdr ), arp_target_pa ( arphdr ), sizeof ( struct in_addr ) );
+ memcpy ( arp_target_ha ( arphdr ), arp_sender_ha ( arphdr ), ETH_ALEN );
+ memcpy ( arp_sender_ha ( arphdr ), netdev->ll_addr, ETH_ALEN );
+
+ /* Fix up ethernet header */
+ ethhdr = iob_push ( iob, sizeof ( *ethhdr ) );
+ memcpy ( ethhdr->h_dest, ethhdr->h_source, ETH_ALEN );
+ memcpy ( ethhdr->h_source, netdev->ll_addr, ETH_ALEN );
+
+ netdev_tx ( netdev, iob );
+ continue; /* no need to free iob */
+ }
+
+ if ( ethhdr->h_protocol != htons ( ETH_P_IP ) ) {
+ goto bad_packet;
+ }
+
+ /* IP header */
+ if ( iob_len ( iob ) < sizeof ( *iphdr ) ) {
+ goto bad_packet;
+ }
+ iphdr = iob->data;
+ iob_pull ( iob, sizeof ( *iphdr ) );
+ if ( iphdr->protocol != IP_UDP || iphdr->dest.s_addr != source_addr.sin_addr.s_addr ) {
+ goto bad_packet;
+ }
+
+ /* UDP header */
+ if ( iob_len ( iob ) < sizeof ( *udphdr ) ) {
+ goto bad_packet;
+ }
+ udphdr = iob->data;
+ if ( udphdr->dest != source_addr.sin_port ) {
+ goto bad_packet;
+ }
+
+ /* Learn the remote connection details */
+ memcpy ( dest_eth, ethhdr->h_source, ETH_ALEN );
+ dest_addr.sin_addr.s_addr = iphdr->src.s_addr;
+ dest_addr.sin_port = udphdr->src;
+
+ /* Payload */
+ payload_len = ntohs ( udphdr->len );
+ if ( payload_len < sizeof ( *udphdr ) || payload_len > iob_len ( iob ) ) {
+ goto bad_packet;
+ }
+ payload_len -= sizeof ( *udphdr );
+ iob_pull ( iob, sizeof ( *udphdr ) );
+ if ( payload_len > len ) {
+ goto bad_packet;
+ }
+ memcpy ( buf, iob->data, payload_len );
+
+ free_iob ( iob );
+ return payload_len;
+
+bad_packet:
+ free_iob ( iob );
+ }
+ cpu_nap();
+ }
+}
+
+static void gdbudp_send ( const char *buf, size_t len ) {
+ struct io_buffer *iob;
+ struct ethhdr *ethhdr;
+ struct iphdr *iphdr;
+ struct udp_header *udphdr;
+
+ /* Check that we are connected */
+ if ( dest_addr.sin_port == 0 ) {
+ return;
+ }
+
+ gdbudp_ensure_netdev_open ( netdev );
+
+ iob = alloc_iob ( sizeof ( *ethhdr ) + sizeof ( *iphdr ) + sizeof ( *udphdr ) + len );
+ if ( !iob ) {
+ return;
+ }
+
+ /* Payload */
+ iob_reserve ( iob, sizeof ( *ethhdr ) + sizeof ( *iphdr ) + sizeof ( *udphdr ) );
+ memcpy ( iob_put ( iob, len ), buf, len );
+
+ /* UDP header */
+ udphdr = iob_push ( iob, sizeof ( *udphdr ) );
+ udphdr->src = source_addr.sin_port;
+ udphdr->dest = dest_addr.sin_port;
+ udphdr->len = htons ( iob_len ( iob ) );
+ udphdr->chksum = 0; /* optional and we are not using it */
+
+ /* IP header */
+ iphdr = iob_push ( iob, sizeof ( *iphdr ) );
+ memset ( iphdr, 0, sizeof ( *iphdr ) );
+ iphdr->verhdrlen = ( IP_VER | ( sizeof ( *iphdr ) / 4 ) );
+ iphdr->service = IP_TOS;
+ iphdr->len = htons ( iob_len ( iob ) );
+ iphdr->ttl = IP_TTL;
+ iphdr->protocol = IP_UDP;
+ iphdr->dest.s_addr = dest_addr.sin_addr.s_addr;
+ iphdr->src.s_addr = source_addr.sin_addr.s_addr;
+ iphdr->chksum = tcpip_chksum ( iphdr, sizeof ( *iphdr ) );
+
+ /* Ethernet header */
+ ethhdr = iob_push ( iob, sizeof ( *ethhdr ) );
+ memcpy ( ethhdr->h_dest, dest_eth, ETH_ALEN );
+ memcpy ( ethhdr->h_source, netdev->ll_addr, ETH_ALEN );
+ ethhdr->h_protocol = htons ( ETH_P_IP );
+
+ netdev_tx ( netdev, iob );
+}
+
+struct gdb_transport *gdbudp_configure ( const char *name, struct sockaddr_in *addr ) {
+ struct settings *settings;
+
+ /* Release old network device */
+ netdev_put ( netdev );
+
+ netdev = find_netdev ( name );
+ if ( !netdev ) {
+ return NULL;
+ }
+
+ /* Hold network device */
+ netdev_get ( netdev );
+
+ /* Source UDP port */
+ source_addr.sin_port = ( addr && addr->sin_port ) ? addr->sin_port : htons ( DEFAULT_PORT );
+
+ /* Source IP address */
+ if ( addr && addr->sin_addr.s_addr ) {
+ source_addr.sin_addr.s_addr = addr->sin_addr.s_addr;
+ } else {
+ settings = netdev_settings ( netdev );
+ fetch_ipv4_setting ( settings, &ip_setting, &source_addr.sin_addr );
+ if ( source_addr.sin_addr.s_addr == 0 ) {
+ netdev_put ( netdev );
+ netdev = NULL;
+ return NULL;
+ }
+ }
+
+ return &udp_gdb_transport;
+}
+
+static int gdbudp_init ( int argc, char **argv ) {
+ if ( argc != 1 ) {
+ printf ( "udp: missing <interface> argument\n" );
+ return 1;
+ }
+
+ if ( !gdbudp_configure ( argv[0], NULL ) ) {
+ printf ( "%s: device does not exist or has no IP address\n", argv[0] );
+ return 1;
+ }
+ return 0;
+}
+
+struct gdb_transport udp_gdb_transport __gdb_transport = {
+ .name = "udp",
+ .init = gdbudp_init,
+ .send = gdbudp_send,
+ .recv = gdbudp_recv,
+};
Code Review / kvmfornfv.git / blobdiff