Solved "use of undeclared identifier 'IFNAMSIZ' char ifname[IFNAMSIZ];" error in pfvar.h

[nactusberrilli]

I'm trying to compile a simple file based on the example introduced in the pf(4).

My code looks like this:

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/fcntl.h>     // manipulate file descriptor                                              
#include <net/pfvar.h>
#include <net/if.h>
#include <netinet/in.h>
#include <err.h>


int main() {

  return 0;

}

On cc -o pftest pftest.c I get this:

In file included from pftest.c:7:
/usr/include/net/pfvar.h:151:18: error: use of undeclared identifier 'IFNAMSIZ'
                char                     ifname[IFNAMSIZ];
                                                ^
/usr/include/net/pfvar.h:415:18: error: use of undeclared identifier 'IFNAMSIZ'
        char                             ifname[IFNAMSIZ];
                                                ^
/usr/include/net/pfvar.h:568:17: error: use of undeclared identifier 'IFNAMSIZ'
        char                     ifname[IFNAMSIZ];
                                        ^
/usr/include/net/pfvar.h:853:16: error: use of undeclared identifier 'IFNAMSIZ'
        char             ifname[IFNAMSIZ];
                                ^
/usr/include/net/pfvar.h:1130:21: error: use of undeclared identifier 'IFNAMSIZ'
        char                             pfik_name[IFNAMSIZ];
                                                   ^
/usr/include/net/pfvar.h:1134:21: error: use of undeclared identifier 'IFNAMSIZ'
        char                             pfik_name[IFNAMSIZ];
                                                   ^
/usr/include/net/pfvar.h:1321:15: error: use of undeclared identifier 'IFNAMSIZ'
        char            ifname[IFNAMSIZ];

Looking at the pfvar.h there is no

ifname[IFNAMSIZ];

at any of the lines specified by the compiler. For example, this is line 151

#define PF_RULES_ASSERT()      rw_assert(&pf_rules_lock, RA_LOCKED)

, this is line 415

SLIST_HEAD(pf_osfp_enlist, pf_osfp_entry) fp_oses; /* list of matches */

, etc. The bottom line is that those errors do not correspond to the src. file.

What am I missing? Thanks.

 

[tobik@]

You need to include net/if.h (that's where IFNAMSIZ is defined) before net/pfvar.h.

I'm trying to compile a simple file based on the example introduced in the pf(8).

pf(8) does not exist. I think you mean pf(4).

 

[fnoyanisi]

nactusberrilli, you may want to use FreeBSD/Linux Kernel Cross Reference to see in which header file any constant or function is originally defined. The web site becomes quite handy if you want to backtrack anything like IFNAMSIZ.

As tobik pointed out, IFNAMSIZ is defined in net/if.h, see lines 60 - 64 in net/if.h.

 

[nactusberrilli]

tobik, thank you for catching that PF error, I edited my post to (hopefully) reflect the change. Adding the if.h header did it. Thanks so much.

fnoyanisi, thank you for the link. I was actually looking for something like that (a place where I can reference header contains).