Re: [Qemu-devel] [PATCH] networking using libpcap

[Laurent Vivier <Laurent.Vivier@bull.net>]

Le mercredi 02 juillet 2008 à 17:25 +0200, Laurent Vivier a écrit :
> I think the patch is broken by your mailer agent.

In fact, the inlined one is broken but the attached one is good...

> Laurent
> 
> Le mercredi 02 juillet 2008 à 17:02 +0200, Ulrich Hecht a écrit :
> > 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	(revision 4820)
> > +++ Makefile.target	(working copy)
> > @@ -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	(revision 4820)
> > +++ vl.c	(working copy)
> > @@ -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)
> 
> ^ Here
>  
> > +{
> > +    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
> 
> > +}
> > +
> > +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 {
> > @@ -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
> > +#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	(revision 4820)
> > +++ configure	(working copy)
> > @@ -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
> > 
> > 
-- 
------------- Laurent.Vivier@bull.net ---------------
"The best way to predict the future is to invent it."
- Alan Kay