From 98198e32d2cc6965656af2b075ec65f5c2a4c4a2 Mon Sep 17 00:00:00 2001
From: Asias He <asias.hejun@gmail.com>
Date: Wed, 29 Jun 2011 16:47:07 +0800
Subject: [PATCH] kvm tools: Add ARP support for uip

- Introduce struct uip_arp to present ARP package
- uip_tx_do_arp()
  Clone incoming ARP ethernet frame, if ARP is requesting
  host IP address, tell guest host MAC address.

Signed-off-by: Asias He <asias.hejun@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
---
 tools/kvm/Makefile          |  1 +
 tools/kvm/include/kvm/uip.h | 15 +++++++++++++++
 tools/kvm/uip/arp.c         | 30 ++++++++++++++++++++++++++++++
 3 files changed, 46 insertions(+)
 create mode 100644 tools/kvm/uip/arp.c

diff --git a/tools/kvm/Makefile b/tools/kvm/Makefile
index 91539de76234..006218d736bc 100644
--- a/tools/kvm/Makefile
+++ b/tools/kvm/Makefile
@@ -45,6 +45,7 @@ OBJS	+= disk/qcow.o
 OBJS	+= disk/raw.o
 OBJS	+= ioeventfd.o
 OBJS	+= irq.o
+OBJS	+= uip/arp.o
 OBJS	+= uip/buf.o
 OBJS	+= kvm-cmd.o
 OBJS	+= kvm-debug.o
diff --git a/tools/kvm/include/kvm/uip.h b/tools/kvm/include/kvm/uip.h
index 32a5da365ad5..c5eb4172206a 100644
--- a/tools/kvm/include/kvm/uip.h
+++ b/tools/kvm/include/kvm/uip.h
@@ -21,6 +21,19 @@ struct uip_eth {
 	u16 type;
 } __attribute__((packed));
 
+struct uip_arp {
+	struct uip_eth eth;
+	u16 hwtype;
+	u16 proto;
+	u8 hwlen;
+	u8 protolen;
+	u16 op;
+	struct uip_eth_addr smac;
+	u32 sip;
+	struct uip_eth_addr dmac;
+	u32 dip;
+} __attribute__((packed));
+
 struct uip_info {
 	struct list_head udp_socket_head;
 	struct list_head tcp_socket_head;
@@ -60,6 +73,8 @@ struct uip_tx_arg {
 	int eth_len;
 };
 
+int uip_tx_do_arp(struct uip_tx_arg *arg);
+
 struct uip_buf *uip_buf_set_used(struct uip_info *info, struct uip_buf *buf);
 struct uip_buf *uip_buf_set_free(struct uip_info *info, struct uip_buf *buf);
 struct uip_buf *uip_buf_get_used(struct uip_info *info);
diff --git a/tools/kvm/uip/arp.c b/tools/kvm/uip/arp.c
new file mode 100644
index 000000000000..98423da6cb19
--- /dev/null
+++ b/tools/kvm/uip/arp.c
@@ -0,0 +1,30 @@
+#include "kvm/uip.h"
+
+int uip_tx_do_arp(struct uip_tx_arg *arg)
+{
+	struct uip_arp *arp, *arp2;
+	struct uip_info *info;
+	struct uip_buf *buf;
+
+	info = arg->info;
+	buf = uip_buf_clone(arg);
+
+	arp	 = (struct uip_arp *)(arg->eth);
+	arp2	 = (struct uip_arp *)(buf->eth);
+
+	/*
+	 * ARP replay code: 2
+	 */
+	arp2->op   = htons(0x2);
+	arp2->dmac = arp->smac;
+	arp2->dip  = arp->sip;
+
+	if (arp->dip == htonl(info->host_ip)) {
+		arp2->smac = info->host_mac;
+		arp2->sip = htonl(info->host_ip);
+
+		uip_buf_set_used(info, buf);
+	}
+
+	return 0;
+}
-- 
2.39.5