networking using libpcap

Hi!

I just discovered this patch

http://lists.freebsd.org/pipermail/freebsd-emulation/2007-February/003107.html

that implements network access using libpcap. Works perfect for me and allows access to the local Ethernet right out of the box, very much unlike tap and bridging. The attached version applies to trunk.

CU
Uli

Index: Makefile.target
===================================================================

Makefile.target +3 -0

@@ -619,6 +619,9 @@
 ifdef CONFIG_SLIRP
 CPPFLAGS+=-I$(SRC_PATH)/slirp
 endif
+ifdef CONFIG_PCAP
+LIBS+=-lpcap
+endif
 
 LIBS+=$(AIOLIBS)
 # specific flags are needed for non soft mmu emulator

Index: vl.c
===================================================================

vl.c +102 -0

@@ -102,6 +102,10 @@
 int inet_aton(const char *cp, struct in_addr *ia);
 #endif
 
+#if defined(CONFIG_PCAP)
+#include <pcap.h>
+#endif
+
 #if defined(CONFIG_SLIRP)
 #include "libslirp.h"
 #endif

@@ -4094,6 +4098,104 @@
 
 #endif /* CONFIG_SLIRP */
 
+#if defined(CONFIG_PCAP)
+
+typedef struct PCAPState {
+    VLANClientState *vc;
+    pcap_t *handle;
+} PCAPState;
+
+static void pcap_receive(void *opaque, const uint8_t *buf, int size)
+{
+    PCAPState *s = (PCAPState *)opaque;
+
+    pcap_sendpacket(s->handle, (u_char*)buf, 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, 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, pcap_receive, 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 {

vl.c +9 -0

@@ -4978,6 +5080,15 @@
         ret = net_slirp_init(vlan);
     } 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, NULL);
+	else
+	    ret = net_pcap_init(vlan, ifname);
+    } else
+#endif
 #ifdef _WIN32
     if (!strcmp(device, "tap")) {
         char ifname[64];

@@ -7381,6 +7492,10 @@
            "                connect the user mode network stack to 

VLAN 'n' and send\n"
" hostname 'host' to DHCP clients\n"
#endif

vl.c +3 -0

+#ifdef CONFIG_PCAP
+           "-net pcap[,vlan=n][,ifname=name]\n"
+           "                connect the host network interface using 

PCAP to VLAN 'n'\n"
+#endif
#ifdef _WIN32
"-net tap[,vlan=n],ifname=name\n"
" connect the host TAP network interface to
VLAN 'n'\n"
Index: configure
===================================================================

configure +7 -0

@@ -89,6 +89,7 @@
 EXESUF=""
 gdbstub="yes"
 slirp="yes"
+pcap="yes"
 fmod_lib=""
 fmod_inc=""
 vnc_tls="yes"

@@ -280,6 +281,8 @@
   ;;
   --disable-slirp) slirp="no"
   ;;
+  --disable-pcap) pcap="no"
+  ;;
   --disable-kqemu) kqemu="no"
   ;;
   --disable-brlapi) brlapi="no"

@@ -1032,6 +1035,10 @@
   echo "CONFIG_SLIRP=yes" >> $config_mak
   echo "#define CONFIG_SLIRP 1" >> $config_h
 fi
+if test "$pcap" = "yes" ; then
+  echo "CONFIG_PCAP=yes" >> $config_mak
+  echo "#define CONFIG_PCAP 1" >> $config_h
+fi
 for card in $audio_card_list; do
     def=CONFIG_`echo $card | tr '[:lower:]' '[:upper:]'`
     echo "$def=yes" >> $config_mak

You could also just use slirp? The difference being that pcap requires root (as would raw sockets, which could also work).

Hi!

I just discovered this patch

http://lists.freebsd.org/pipermail/freebsd-emulation/2007-February/003107.html

that implements network access using libpcap. Works perfect for me and allows access to the local Ethernet right out of the box, very much unlike tap and bridging. The attached version applies to trunk.

CU
Uli

Index: Makefile.target
===================================================================

Makefile.target +3 -0

@@ -619,6 +619,9 @@
 ifdef CONFIG_SLIRP
 CPPFLAGS+=-I$(SRC_PATH)/slirp
 endif
+ifdef CONFIG_PCAP
+LIBS+=-lpcap
+endif
 
 LIBS+=$(AIOLIBS)
 # specific flags are needed for non soft mmu emulator

Index: vl.c
===================================================================

vl.c +10 -0

@@ -102,6 +102,10 @@
 int inet_aton(const char *cp, struct in_addr *ia);
 #endif
 
+#if defined(CONFIG_PCAP)
+#include <pcap.h>
+#endif
+
 #if defined(CONFIG_SLIRP)
 #include "libslirp.h"
 #endif

@@ -4094,6 +4098,104 @@
 
 #endif /* CONFIG_SLIRP */
 
+#if defined(CONFIG_PCAP)
+
+typedef struct PCAPState {
+    VLANClientState *vc;
+    pcap_t *handle;
+} PCAPState;

vl.c +72 -0

+}
+
+static int net_pcap_init(VLANState *vlan, 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, pcap_receive, 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 {

vl.c +9 -0

@@ -4978,6 +5080,15 @@
         ret = net_slirp_init(vlan);
     } 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, NULL);
+	else
+	    ret = net_pcap_init(vlan, ifname);
+    } else
+#endif
 #ifdef _WIN32
     if (!strcmp(device, "tap")) {
         char ifname[64];

@@ -7381,6 +7492,10 @@
            "                connect the user mode network stack to 

VLAN 'n' and send\n"
" hostname 'host' to DHCP clients\n"
#endif

vl.c +3 -0

+#ifdef CONFIG_PCAP
+           "-net pcap[,vlan=n][,ifname=name]\n"
+           "                connect the host network interface using 

PCAP to VLAN 'n'\n"
+#endif
#ifdef _WIN32
"-net tap[,vlan=n],ifname=name\n"
" connect the host TAP network interface to
VLAN 'n'\n"
Index: configure
===================================================================

configure +7 -0

@@ -89,6 +89,7 @@
 EXESUF=""
 gdbstub="yes"
 slirp="yes"
+pcap="yes"
 fmod_lib=""
 fmod_inc=""
 vnc_tls="yes"

@@ -280,6 +281,8 @@
   ;;
   --disable-slirp) slirp="no"
   ;;
+  --disable-pcap) pcap="no"
+  ;;
   --disable-kqemu) kqemu="no"
   ;;
   --disable-brlapi) brlapi="no"

@@ -1032,6 +1035,10 @@
   echo "CONFIG_SLIRP=yes" >> $config_mak
   echo "#define CONFIG_SLIRP 1" >> $config_h
 fi
+if test "$pcap" = "yes" ; then
+  echo "CONFIG_PCAP=yes" >> $config_mak
+  echo "#define CONFIG_PCAP 1" >> $config_h
+fi
 for card in $audio_card_list; do
     def=CONFIG_`echo $card | tr '[:lower:]' '[:upper:]'`
     echo "$def=yes" >> $config_mak

I think the patch is broken by your mailer agent.

Laurent

Quoted 52 lines · Ulrich Hecht

Hi!

I just discovered this patch

http://lists.freebsd.org/pipermail/freebsd-emulation/2007-February/003107.html

that implements network access using libpcap. Works perfect for me and allows access to the local Ethernet right out of the box, very much unlike tap and bridging. The attached version applies to trunk.

CU
Uli

Index: Makefile.target
===================================================================

Makefile.target +3 -0

@@ -619,6 +619,9 @@
 ifdef CONFIG_SLIRP
 CPPFLAGS+=-I$(SRC_PATH)/slirp
 endif
+ifdef CONFIG_PCAP
+LIBS+=-lpcap
+endif
 
 LIBS+=$(AIOLIBS)
 # specific flags are needed for non soft mmu emulator

Index: vl.c
===================================================================

vl.c +10 -0

@@ -102,6 +102,10 @@
 int inet_aton(const char *cp, struct in_addr *ia);
 #endif
 
+#if defined(CONFIG_PCAP)
+#include <pcap.h>
+#endif
+
 #if defined(CONFIG_SLIRP)
 #include "libslirp.h"
 #endif

@@ -4094,6 +4098,104 @@
 
 #endif /* CONFIG_SLIRP */
 
+#if defined(CONFIG_PCAP)
+
+typedef struct PCAPState {
+    VLANClientState *vc;
+    pcap_t *handle;
+} PCAPState;

vl.c line 4116

Quoted 10 lines

vl.c +9 -0

+
+static void pcap_receive(void *opaque, const uint8_t *buf, int size)
+{
+    PCAPState *s = (PCAPState *)opaque;
+
+    pcap_sendpacket(s->handle, (u_char*)buf, size);
+}
+
+static void pcap_callback(u_char *user, struct pcap_pkthdr *phdr, u_char 
 *pdata)

^ Here

vl.c

Quoted 12 lines

vl.c +11 -0

+{
+    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);

^Here

Quoted 140 lines

vl.c +72 -0

+}
+
+static int net_pcap_init(VLANState *vlan, 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, pcap_receive, 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 {

vl.c +9 -0

@@ -4978,6 +5080,15 @@
         ret = net_slirp_init(vlan);
     } 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, NULL);
+	else
+	    ret = net_pcap_init(vlan, ifname);
+    } else
+#endif
 #ifdef _WIN32
     if (!strcmp(device, "tap")) {
         char ifname[64];

@@ -7381,6 +7492,10 @@
            "                connect the user mode network stack to 

VLAN 'n' and send\n"
" hostname 'host' to DHCP clients\n"
#endif

vl.c +3 -0

+#ifdef CONFIG_PCAP
+           "-net pcap[,vlan=n][,ifname=name]\n"
+           "                connect the host network interface using 

PCAP to VLAN 'n'\n"
+#endif
#ifdef _WIN32
"-net tap[,vlan=n],ifname=name\n"
" connect the host TAP network interface to
VLAN 'n'\n"
Index: configure
===================================================================

configure +7 -0

@@ -89,6 +89,7 @@
 EXESUF=""
 gdbstub="yes"
 slirp="yes"
+pcap="yes"
 fmod_lib=""
 fmod_inc=""
 vnc_tls="yes"

@@ -280,6 +281,8 @@
   ;;
   --disable-slirp) slirp="no"
   ;;
+  --disable-pcap) pcap="no"
+  ;;
   --disable-kqemu) kqemu="no"
   ;;
   --disable-brlapi) brlapi="no"

@@ -1032,6 +1035,10 @@
   echo "CONFIG_SLIRP=yes" >> $config_mak
   echo "#define CONFIG_SLIRP 1" >> $config_h
 fi
+if test "$pcap" = "yes" ; then
+  echo "CONFIG_PCAP=yes" >> $config_mak
+  echo "#define CONFIG_PCAP 1" >> $config_h
+fi
 for card in $audio_card_list; do
     def=CONFIG_`echo $card | tr '[:lower:]' '[:upper:]'`
     echo "$def=yes" >> $config_mak

I just discovered this patch

http://lists.freebsd.org/pipermail/freebsd-emulation/2007-February/003107.html

that implements network access using libpcap. Works perfect for me and allows access to the local Ethernet right out of the box, very much unlike tap and bridging. The attached version applies to trunk.