qemu/0015-pcap-network-emulation.patch

From 99759e033ea960b86828657682f8382538c4ccb7 Mon Sep 17 00:00:00 2001
From: Ulrich Hecht <uli@suse.de>
Date: Tue, 14 Apr 2009 16:52:51 +0200
Subject: [PATCH 15/33] pcap network emulation

Implements network emulation using libpcap; useful for direct Ethernet access.

Signed-off-by: Ulrich Hecht <uli@suse.de>
---
 Makefile.target |    3 ++
 configure       |    7 ++++
 net.c           |  108 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 qemu-options.hx |    4 ++
 4 files changed, 122 insertions(+), 0 deletions(-)

diff --git a/Makefile.target b/Makefile.target
index f9cd42a..9c9304c 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -618,6 +618,9 @@ endif
 ifdef CONFIG_SLIRP
 CPPFLAGS+=-I$(SRC_PATH)/slirp
 endif
+ifdef CONFIG_PCAP
+LIBS+=-lpcap
+endif
 
 # specific flags are needed for non soft mmu emulator
 ifdef CONFIG_STATIC
diff --git a/configure b/configure
index cac4198..4ce7bc1 100755
--- a/configure
+++ b/configure
@@ -169,6 +169,7 @@ mingw32="no"
 EXESUF=""
 slirp="yes"
 vde="yes"
+pcap="yes"
 fmod_lib=""
 fmod_inc=""
 oss_lib=""
@@ -432,6 +433,8 @@ for opt do
   ;;
   --disable-vde) vde="no"
   ;;
+  --disable-pcap) pcap="no"
+  ;;
   --disable-kqemu) kqemu="no"
   ;;
   --disable-xen) xen="no"
@@ -1598,6 +1601,10 @@ if test "$vde" = "yes" ; then
   echo "#define CONFIG_VDE 1" >> $config_host_h
   echo "VDE_LIBS=-lvdeplug" >> $config_host_mak
 fi
+if test "$pcap" = "yes" ; then
+  echo "CONFIG_PCAP=yes" >> $config_host_mak
+  echo "#define CONFIG_PCAP 1" >> $config_host_h
+fi
 for card in $audio_card_list; do
     def=CONFIG_`echo $card | tr '[:lower:]' '[:upper:]'`
     echo "$def=y" >> $config_host_mak
diff --git a/net.c b/net.c
index 3d3829d..595f7bc 100644
--- a/net.c
+++ b/net.c
@@ -1264,6 +1264,105 @@ void do_info_usernet(Monitor *mon)
 
 #endif /* CONFIG_SLIRP */
 
+#if defined(CONFIG_PCAP)
+#include <pcap.h>
+typedef struct PCAPState {
+    VLANClientState *vc;
+    pcap_t *handle;
+} PCAPState;
+
+static ssize_t pcap_receive(VLANClientState *vc, const uint8_t *buf, size_t size)
+{
+    PCAPState *s = (PCAPState *)(vc->opaque);
+
+    pcap_sendpacket(s->handle, (u_char*)buf, size);
+    return size;
+}
+
+static void pcap_callback(u_char *user, struct pcap_pkthdr *phdr, u_char *pdata)
+{
+    VLANClientState *vc = (VLANClientState *)user;
+
+    qemu_send_packet(vc, pdata, phdr->len);
+}
+
+static void pcap_send(void *opaque)
+{
+    PCAPState *s = (PCAPState *)opaque;
+
+    pcap_dispatch(s->handle, 1, (pcap_handler)&pcap_callback, (u_char *)s->vc);
+}
+
+static int net_pcap_init(VLANState *vlan, const char *model, const char *name, char *ifname)
+{
+    PCAPState *s;
+    char errbuf[PCAP_ERRBUF_SIZE];
+    int fd;
+
+    s = qemu_mallocz(sizeof(PCAPState));
+    if (!s)
+        return -1;
+
+    if (ifname == NULL && (ifname = pcap_lookupdev(errbuf)) == NULL) {
+	fprintf(stderr, "qemu: pcap_lookupdev: %s\n", errbuf);
+	goto fail;
+    }
+
+    /* Attempt to connect device. */
+    s->handle = (void*)pcap_open_live(ifname, 65535, 1, 0, errbuf);
+    if (!s->handle) {
+	fprintf(stderr, "qemu: pcap_open_live: %s\n", errbuf);
+	goto fail;
+    }
+
+    /* Check non-blocking mode. */
+    if (pcap_setnonblock(s->handle, 1, errbuf) < 0) {
+	fprintf(stderr, "qemu: pcap_setnonblock: %s\n", errbuf);
+	goto fail;
+    }
+
+#if defined(BIOCSHDRCMPLT)
+    /*
+     * Tell the kernel that the header is fully-formed when it gets it.
+     * This is required in order to fake the src address.
+     */
+    {
+	unsigned int one = 1;
+	ioctl(pcap_fileno(s->handle), BIOCSHDRCMPLT, &one);
+    }
+#endif /* BIOCSHDRCMPLT */
+
+#if defined(BIOCIMMEDIATE)
+    /*
+     * Tell the kernel that the packet has to be processed immediately.
+     */
+    {
+	unsigned int one = 1;
+	ioctl(pcap_fileno(s->handle), BIOCIMMEDIATE, &one);
+    }
+#endif /* BIOCIMMEDIATE */
+
+    s->vc = qemu_new_vlan_client(vlan, model, name, NULL, pcap_receive, NULL, NULL, s);
+    snprintf(s->vc->info_str, sizeof(s->vc->info_str), "pcap redirector");
+    if ((fd = pcap_get_selectable_fd(s->handle)) < 0) {
+	fprintf(stderr, "qemu: pcap_get_selectable_fd failed\n");
+	goto fail;
+    }
+    qemu_set_fd_handler(fd, pcap_send, NULL, s);
+
+    return 0;
+
+fail:
+    if (s) {
+	if (s->handle)
+	    pcap_close(s->handle);
+	qemu_free(s);
+    }
+
+    return -1;
+}
+#endif /* CONFIG_PCAP */
+
 #if !defined(_WIN32)
 
 typedef struct TAPState {
@@ -2631,6 +2730,15 @@ int net_client_init(Monitor *mon, const char *device, const char *p)
         ret = 0;
     } else
 #endif
+#ifdef CONFIG_PCAP
+    if (!strcmp(device, "pcap")) {
+	char ifname[64];
+	if (get_param_value(ifname, sizeof(ifname), "ifname", p) <= 0)
+	    ret = net_pcap_init(vlan, device, name, NULL);
+	else
+	    ret = net_pcap_init(vlan, device, name, ifname);
+    } else
+#endif
 #ifdef _WIN32
     if (!strcmp(device, "tap")) {
         static const char * const tap_params[] = {
diff --git a/qemu-options.hx b/qemu-options.hx
index a58287c..4d46d6c 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -801,6 +801,10 @@ DEF("net", HAS_ARG, QEMU_OPTION_net,
     "                default of 'sndbuf=1048576' can be disabled using 'sndbuf=0'\n"
 #endif
 #endif
+#ifdef CONFIG_PCAP
+    "-net pcap[,vlan=n][,ifname=name]\n"
+    "                connect the host network interface using PCAP to VLAN 'n'\n"
+#endif
     "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
     "                connect the vlan 'n' to another VLAN using a socket connection\n"
     "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port]\n"
-- 
1.6.2.1