PAM module compilation

[psih]

I'm trying to compile my own PAM module, I wrote a simplest ever module, wich always succeeds, and a simplest ever application to use this module. When I call the authentication function from the application, it always responses with PAM_MODULE_UNKNOWN (error 28). So the problem is how to compile the module correctly.

Here are codes:
PAM module


#include <stdio.h>

#include <security/pam_modules.h>
#include <security/_pam_macros.h>

/* --- authentication management functions --- */

PAM_EXTERN int
pam_sm_authenticate(pam_handle_t *pamh, int flags ,
int argc , const char **argv )
{
return PAM_SUCCESS;
}

/* end of module definition */

#ifdef PAM_STATIC

/* static module data */

struct pam_module _pam_permit_t_modstruct = {
"pam_permit_t",
pam_sm_authenticate,
NULL,
NULL,
NULL,
NULL,
NULL
};

#endif


application


#include <security/pam_appl.h>
#include <security/pam_misc.h>

#include <stdlib.h>
#include <stdio.h>

static struct pam_conv conv = {
misc_conv,
NULL
};

int main(int argc, char *argv[])
{
pam_handle_t *pamh = NULL;
int pam_err;

pam_err = pam_start("test_app", NULL, &conv, &pamh);
if( pam_err != PAM_SUCCESS)
{
printf("pam_start error: %d\n", pam_err);
return pam_err;
}
pam_err = pam_authenticate(pamh, 0);
if( pam_err != PAM_SUCCESS)
{
printf("pam_authenticate error: %d\n", pam_err);
return pam_err;
}
}


What gcc keys do I have to use? I was trying to do everything with respect to the Linux-PAM manual (http://www.kernel.org/pub/linux/libs/pam/Linux-PAM-html/), and here is how I compile the module and application:

module


gcc -fPIC -c pam_permit_t.c
ld -x --shared -o /lib/security/pam_permit_t.so pam_permit_t.o


application


gcc -gstabs -o test_app test_app.c -lpam -lpam_misc -ldl