#if DLOPEN_PAM/* * If you want to dynamically load libpam using dlopen() or something, * then dlopen( ' this shared object ' ); It takes care of exporting * the right symbols to any modules loaded by libpam. * * Modified by JY for use with openvpn-pam-auth */#include <stdio.h>#include <dlfcn.h>#include <security/pam_appl.h>#include <security/_pam_macros.h>#include "pamdl.h"static void *libpam_h = NULL;#define RESOLVE_PAM_FUNCTION(x, y, z, err) \    { \        union { const void *tpointer; y (*fn) z ; } fptr; \	fptr.tpointer = dlsym(libpam_h, #x); real_##x = fptr.fn; \	if (real_##x == NULL) { \	    fprintf (stderr, "PAMDL: unable to resolve '%s': %s\n", #x, dlerror()); \	    return err; \	} \    }intdlopen_pam (const char *so){  if (libpam_h == NULL)    {      libpam_h = dlopen(so, RTLD_GLOBAL|RTLD_NOW);    }  return libpam_h != NULL;}voiddlclose_pam (void){  if (libpam_h != NULL)    {      dlclose(libpam_h);      libpam_h = NULL;    }}int pam_start(const char *service_name, const char *user,	      const struct pam_conv *pam_conversation,	      pam_handle_t **pamh){    int (*real_pam_start)(const char *, const char *,				 const struct pam_conv *,				 pam_handle_t **);    RESOLVE_PAM_FUNCTION(pam_start, int, (const char *, const char *,					  const struct pam_conv *,					  pam_handle_t **), PAM_ABORT);    return real_pam_start(service_name, user, pam_conversation, pamh);}int pam_end(pam_handle_t *pamh, int pam_status){    int (*real_pam_end)(pam_handle_t *, int);    RESOLVE_PAM_FUNCTION(pam_end, int, (pam_handle_t *, int), PAM_ABORT);    return real_pam_end(pamh, pam_status);}int pam_set_item(pam_handle_t *pamh, int item_type, const void *item){    int (*real_pam_set_item)(pam_handle_t *, int, const void *);    RESOLVE_PAM_FUNCTION(pam_set_item, int,			 (pam_handle_t *, int, const void *), PAM_ABORT);    return real_pam_set_item(pamh, item_type, item);}int pam_get_item(const pam_handle_t *pamh, int item_type, const void **item){    int (*real_pam_get_item)(const pam_handle_t *, int, const void **);    RESOLVE_PAM_FUNCTION(pam_get_item, int,			 (const pam_handle_t *, int, const void **),			 PAM_ABORT);    return real_pam_get_item(pamh, item_type, item);}int pam_fail_delay(pam_handle_t *pamh, unsigned int musec_delay){    int (*real_pam_fail_delay)(pam_handle_t *, unsigned int);    RESOLVE_PAM_FUNCTION(pam_fail_delay, int, (pam_handle_t *, unsigned int),			 PAM_ABORT);    return real_pam_fail_delay(pamh, musec_delay);}typedef const char * const_char_pointer;const_char_pointer pam_strerror(pam_handle_t *pamh, int errnum){    const_char_pointer (*real_pam_strerror)(pam_handle_t *, int);    RESOLVE_PAM_FUNCTION(pam_strerror, const_char_pointer,			 (pam_handle_t *, int), NULL);    return real_pam_strerror(pamh, errnum);}int pam_putenv(pam_handle_t *pamh, const char *name_value){    int (*real_pam_putenv)(pam_handle_t *, const char *);    RESOLVE_PAM_FUNCTION(pam_putenv, int, (pam_handle_t *, const char *),			 PAM_ABORT);    return real_pam_putenv(pamh, name_value);}const_char_pointer pam_getenv(pam_handle_t *pamh, const char *name){    const_char_pointer (*real_pam_getenv)(pam_handle_t *, const char *);    RESOLVE_PAM_FUNCTION(pam_getenv, const_char_pointer,			 (pam_handle_t *, const char *), NULL);    return real_pam_getenv(pamh, name);}typedef char ** char_ppointer;char_ppointer pam_getenvlist(pam_handle_t *pamh){    char_ppointer (*real_pam_getenvlist)(pam_handle_t *);    RESOLVE_PAM_FUNCTION(pam_getenvlist, char_ppointer, (pam_handle_t *),			 NULL);    return real_pam_getenvlist(pamh);}/* Authentication management */int pam_authenticate(pam_handle_t *pamh, int flags){    int (*real_pam_authenticate)(pam_handle_t *, int);    RESOLVE_PAM_FUNCTION(pam_authenticate, int, (pam_handle_t *, int),			 PAM_ABORT);    return real_pam_authenticate(pamh, flags);}int pam_setcred(pam_handle_t *pamh, int flags){    int (*real_pam_setcred)(pam_handle_t *, int);    RESOLVE_PAM_FUNCTION(pam_setcred, int, (pam_handle_t *, int), PAM_ABORT);    return real_pam_setcred(pamh, flags);}/* Account Management API's */int pam_acct_mgmt(pam_handle_t *pamh, int flags){    int (*real_pam_acct_mgmt)(pam_handle_t *, int);    RESOLVE_PAM_FUNCTION(pam_acct_mgmt, int, (pam_handle_t *, int), PAM_ABORT);    return real_pam_acct_mgmt(pamh, flags);}/* Session Management API's */int pam_open_session(pam_handle_t *pamh, int flags){    int (*real_pam_open_session)(pam_handle_t *, int);    RESOLVE_PAM_FUNCTION(pam_open_session, int, (pam_handle_t *, int),			 PAM_ABORT);    return real_pam_open_session(pamh, flags);}int pam_close_session(pam_handle_t *pamh, int flags){    int (*real_pam_close_session)(pam_handle_t *, int);    RESOLVE_PAM_FUNCTION(pam_close_session, int, (pam_handle_t *, int),			 PAM_ABORT);    return real_pam_close_session(pamh, flags);}/* Password Management API's */int pam_chauthtok(pam_handle_t *pamh, int flags){    int (*real_pam_chauthtok)(pam_handle_t *, int);    RESOLVE_PAM_FUNCTION(pam_chauthtok, int, (pam_handle_t *, int), PAM_ABORT);    return real_pam_chauthtok(pamh, flags);}#endif