On Tue, Apr 30, 2002 at 10:20:47AM +0200, Brad Knowles wrote:
> The segment of code that calls this routine says:
>
> if (pcap_lookupnet(iname, (uint32_t *)&(interf.net),
> (uint32_t *)&(interf.netmask), errbuf) < 0) {
> fprintf(stderr,"pcap_lookupnet: %s\n",errbuf);
> return -1;
> }
>
> Looking at the libpcap header files, it seems that pcap.h defines:
>
> /*
> * Compatibility for systems that have a bpf.h that
> * predates the bpf typedefs for 64-bit support.
> */
> #if BPF_RELEASE - 0 < 199406
> typedef int bpf_int32;
> typedef u_int bpf_u_int32;
> #endif
>
> But this value does not seem to be otherwise defined anywhere in
> /usr/local/include/pcap*.h -- the value is used in a variety of
> places, but this seems to be the only potential definition.
Well, yes, the idea is that on systems where BPF_RELEASE is defined and
has a value of 199406 or greater, <net/bpf.h> defines bpf_int32 and
bpf_u_int32.
<pcap.h> from tcpdump.org includes <net/bpf.h>, so if <net/bpf.h> either
defines BPF_RELEASE as a value >= 199406 and has typedefs for bpf_int32
and bpf_u_int32, or doesn't define BPF_RELEASE, or defines it as a value
< 199406, either <pcap.h> will define them itself or will include a
header file that defines them.
Therefore, either
1) whatever <pcap.h> you're including isn't the one from
tcpdump.org
or
2) <pcap.h> is including some version of <net/bpf.h> that
defines BPF_RELEASE as a value >= 199406 but that *doesn't*
have typedefs for bpf_int32 and bpf_u_int32.
> Partially. Using the same definitions for lo0, en0, and en1 that
> were previously posted, I get:
>
> # xprobe -v -i lo0 127.0.0.1
> X probe ver. 0.0.2
> ------------------
> Interface: lo0/127.0.0.1
[success]
> # xprobe -v -i en1 10.0.1.12
> X probe ver. 0.0.2
> ------------------
> ioctl(SIOCGIFADDR): Can't assign requested address
That's not the error that libpcap 0.7.1 generates for a failed
SIOCGIFADDR, so that's presumably an error coming from xprobe itself,
not libpcap.
As such, I don't know why xprobe with no "-i" argument was failing to
find or open en1.
I've attached the test program that the guy who did the
"pcap_findalldevs()" did as a test program; try compiling that, and
linking it with the version of libpcap 0.7.1 you built, and run it as
root, and see what it reports.
> Hmm. Maybe my failures were a result of a DHCP license that was
> in the process of being dropped and renewed? Things seem to have
> worked okay afterwards.
Could be - but that shouldn't have caused pcap_open_live() to fail, just
caused "pcap_lookupnet()", or something inside xprobe itself, to fail.
#include "pcap.h"
#include <sys/socket.h>
#include <netinet/in.h>
void ifprint(pcap_if_t *d);
char *iptos(u_long in);
int main()
{
pcap_if_t *alldevs;
pcap_if_t *d;
char *s;
bpf_u_int32 net, mask;
char errbuf[PCAP_ERRBUF_SIZE+1];
if (pcap_findalldevs(&alldevs, errbuf) == -1)
{
fprintf(stderr,"Error in pcap_findalldevs: %s\n",errbuf);
exit(1);
}
for(d=alldevs;d;d=d->next)
{
ifprint(d);
}
if ( (s = pcap_lookupdev(errbuf)) == NULL)
{
fprintf(stderr,"Error in pcap_lookupdev: %s\n",errbuf);
}
else
{
printf("Preferred device name: %s\n",s);
}
if (pcap_lookupnet(s, &net, &mask, errbuf) < 0)
{
fprintf(stderr,"Error in pcap_lookupnet: %s\n",errbuf);
}
else
{
printf("Preferred device is on network: %s/%s\n",iptos(net), iptos(mask));
}
exit(0);
}
void ifprint(pcap_if_t *d)
{
pcap_addr_t *a;
printf("%s\n",d->name);
if (d->description)
printf("\tDescription: %s\n",d->description);
printf("\tLoopback: %s\n",(d->flags & PCAP_IF_LOOPBACK)?"yes":"no");
for(a=d->addresses;a;a=a->next) {
printf("\tAddress Family: #%d\n",a->addr->sa_family);
switch(a->addr->sa_family)
{
case AF_INET:
printf("\tAddress Family Name: AF_INET\n");
if (a->addr)
printf("\tAddress: %s\n",iptos(((struct sockaddr_in
*)a->addr)->sin_addr.s_addr));
if (a->netmask)
printf("\tNetmask: %s\n",iptos(((struct sockaddr_in
*)a->netmask)->sin_addr.s_addr));
if (a->broadaddr)
printf("\tBroadcast Address: %s\n",iptos(((struct sockaddr_in
*)a->broadaddr)->sin_addr.s_addr));
if (a->dstaddr)
printf("\tDestination Address: %s\n",iptos(((struct sockaddr_in
*)a->dstaddr)->sin_addr.s_addr));
break;
default:
printf("\tAddress Family Name: Unknown\n");
break;
}
}
printf("\n");
}
/* From tcptraceroute */
#define IPTOSBUFFERS 12
char *iptos(u_long in)
{
static char output[IPTOSBUFFERS][3*4+3+1];
static short which;
u_char *p;
p = (u_char *)∈
which = (which + 1 == IPTOSBUFFERS ? 0 : which + 1);
sprintf(output[which], "%d.%d.%d.%d", p[0], p[1], p[2], p[3]);
return output[which];
}
