/* Copyright (C) 1996,1997,1998,1999,2002,2004,2005,2007,2011 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #include #include #include #include #include #include #include #include #include "netgroup.h" #include "nsswitch.h" #include /* Protect above variable against multiple uses at the same time. */ __libc_lock_define_initialized (static, lock) /* The whole information for the set/get/endnetgrent functions are kept in this structure. */ static struct __netgrent dataset; /* The lookup function for the first entry of this service. */ extern int __nss_netgroup_lookup (service_user **nipp, const char *name, void **fctp) internal_function; /* Set up NIP to run through the services. Return nonzero if there are no services (left). */ static int setup (void **fctp, service_user **nipp) { /* Remember the first service_entry, it's always the same. */ static bool startp_initialized; static service_user *startp; int no_more; if (!startp_initialized) { /* Executing this more than once at the same time must yield the same result every time. So we need no locking. */ no_more = __nss_netgroup_lookup (nipp, "setnetgrent", fctp); startp = no_more ? (service_user *) -1 : *nipp; PTR_MANGLE (startp); atomic_write_barrier (); startp_initialized = true; } else { service_user *nip = startp; PTR_DEMANGLE (nip); if (nip == (service_user *) -1) /* No services at all. */ return 1; /* Reset to the beginning of the service list. */ *nipp = nip; /* Look up the first function. */ no_more = __nss_lookup (nipp, "setnetgrent", NULL, fctp); } return no_more; } /* Free used memory. */ static void free_memory (struct __netgrent *data) { while (data->known_groups != NULL) { struct name_list *tmp = data->known_groups; data->known_groups = data->known_groups->next; free (tmp); } while (data->needed_groups != NULL) { struct name_list *tmp = data->needed_groups; data->needed_groups = data->needed_groups->next; free (tmp); } } static void endnetgrent_hook (struct __netgrent *datap) { enum nss_status (*endfct) (struct __netgrent *); if (datap->nip == NULL) return; endfct = __nss_lookup_function (datap->nip, "endnetgrent"); if (endfct != NULL) (void) (*endfct) (datap); datap->nip = NULL; } static int internal_function __internal_setnetgrent_reuse (const char *group, struct __netgrent *datap, int *errnop) { union { enum nss_status (*f) (const char *, struct __netgrent *); void *ptr; } fct; enum nss_status status = NSS_STATUS_UNAVAIL; struct name_list *new_elem; /* Free data from previous service. */ endnetgrent_hook (datap); /* Cycle through all the services and run their setnetgrent functions. */ int no_more = setup (&fct.ptr, &datap->nip); while (! no_more) { assert (datap->data == NULL); /* Ignore status, we force check in `__nss_next2'. */ status = DL_CALL_FCT (*fct.f, (group, datap)); service_user *old_nip = datap->nip; no_more = __nss_next2 (&datap->nip, "setnetgrent", NULL, &fct.ptr, status, 0); if (status == NSS_STATUS_SUCCESS && ! no_more) { enum nss_status (*endfct) (struct __netgrent *); endfct = __nss_lookup_function (old_nip, "endnetgrent"); if (endfct != NULL) (void) DL_CALL_FCT (*endfct, (datap)); } } /* Add the current group to the list of known groups. */ size_t group_len = strlen (group) + 1; new_elem = (struct name_list *) malloc (sizeof (struct name_list) + group_len); if (new_elem == NULL) { *errnop = errno; status = NSS_STATUS_TRYAGAIN; } else { new_elem->next = datap->known_groups; memcpy (new_elem->name, group, group_len); datap->known_groups = new_elem; } return status == NSS_STATUS_SUCCESS; } int internal_setnetgrent (const char *group, struct __netgrent *datap); libc_hidden_proto (internal_setnetgrent) int internal_setnetgrent (const char *group, struct __netgrent *datap) { /* Free list of all netgroup names from last run. */ free_memory (datap); return __internal_setnetgrent_reuse (group, datap, &errno); } libc_hidden_def (internal_setnetgrent) strong_alias (internal_setnetgrent, __internal_setnetgrent) int setnetgrent (const char *group) { int result; __libc_lock_lock (lock); result = internal_setnetgrent (group, &dataset); __libc_lock_unlock (lock); return result; } void internal_endnetgrent (struct __netgrent *datap); libc_hidden_proto (internal_endnetgrent) void internal_endnetgrent (struct __netgrent *datap) { endnetgrent_hook (datap); /* Now free list of all netgroup names from last run. */ free_memory (datap); } libc_hidden_def (internal_endnetgrent) strong_alias (internal_endnetgrent, __internal_endnetgrent) void endnetgrent (void) { __libc_lock_lock (lock); internal_endnetgrent (&dataset); __libc_lock_unlock (lock); } int internal_getnetgrent_r (char **hostp, char **userp, char **domainp, struct __netgrent *datap, char *buffer, size_t buflen, int *errnop); libc_hidden_proto (internal_getnetgrent_r) int internal_getnetgrent_r (char **hostp, char **userp, char **domainp, struct __netgrent *datap, char *buffer, size_t buflen, int *errnop) { enum nss_status (*fct) (struct __netgrent *, char *, size_t, int *); /* Initialize status to return if no more functions are found. */ enum nss_status status = NSS_STATUS_NOTFOUND; /* Run through available functions, starting with the same function last run. We will repeat each function as long as it succeeds, and then go on to the next service action. */ int no_more = (datap->nip == NULL || (fct = __nss_lookup_function (datap->nip, "getnetgrent_r")) == NULL); while (! no_more) { status = DL_CALL_FCT (*fct, (datap, buffer, buflen, &errno)); if (status == NSS_STATUS_RETURN) { /* This was the last one for this group. Look at next group if available. */ int found = 0; while (datap->needed_groups != NULL && ! found) { struct name_list *tmp = datap->needed_groups; datap->needed_groups = datap->needed_groups->next; tmp->next = datap->known_groups; datap->known_groups = tmp; found = __internal_setnetgrent_reuse (datap->known_groups->name, datap, errnop); } if (found && datap->nip != NULL) { fct = __nss_lookup_function (datap->nip, "getnetgrent_r"); if (fct != NULL) continue; } } else if (status == NSS_STATUS_SUCCESS && datap->type == group_val) { /* The last entry was a name of another netgroup. */ struct name_list *namep; /* Ignore if we've seen the name before. */ for (namep = datap->known_groups; namep != NULL; namep = namep->next) if (strcmp (datap->val.group, namep->name) == 0) break; if (namep == NULL) for (namep = datap->needed_groups; namep != NULL; namep = namep->next) if (strcmp (datap->val.group, namep->name) == 0) break if (namep != NULL) /* Really ignore. */ continue; size_t group_len = strlen (datap->val.group) + 1; namep = (struct name_list *) malloc (sizeof (struct name_list) + group_len); if (namep == NULL) /* We are out of memory. */ status = NSS_STATUS_RETURN; else { namep->next = datap->needed_groups; memcpy (namep->name, datap->val.group, group_len); datap->needed_groups = namep; /* And get the next entry. */ continue; } } break; } if (status == NSS_STATUS_SUCCESS) { *hostp = (char *) datap->val.triple.host; *userp = (char *) datap->val.triple.user; *domainp = (char *) datap->val.triple.domain; } return status == NSS_STATUS_SUCCESS ? 1 : 0; } libc_hidden_def (internal_getnetgrent_r) strong_alias (internal_getnetgrent_r, __internal_getnetgrent_r) /* The real entry point. */ int __getnetgrent_r (char **hostp, char **userp, char **domainp, char *buffer, size_t buflen) { enum nss_status status; __libc_lock_lock (lock); status = internal_getnetgrent_r (hostp, userp, domainp, &dataset, buffer, buflen, &errno); __libc_lock_unlock (lock); return status; } weak_alias (__getnetgrent_r, getnetgrent_r) /* Test whether given (host,user,domain) triple is in NETGROUP. */ int innetgr (const char *netgroup, const char *host, const char *user, const char *domain) { union { enum nss_status (*f) (const char *, struct __netgrent *); void *ptr; } setfct; void (*endfct) (struct __netgrent *); int (*getfct) (struct __netgrent *, char *, size_t, int *); struct __netgrent entry; int result = 0; const char *current_group = netgroup; memset (&entry, '\0', sizeof (entry)); /* Walk through the services until we found an answer or we shall not work further. We can do some optimization here. Since all services must provide the `setnetgrent' function we can do all the work during one walk through the service list. */ while (1) { int no_more = setup (&setfct.ptr, &entry.nip); while (! no_more) { assert (entry.data == NULL); /* Open netgroup. */ enum nss_status status = DL_CALL_FCT (*setfct.f, (current_group, &entry)); if (status == NSS_STATUS_SUCCESS && (getfct = __nss_lookup_function (entry.nip, "getnetgrent_r")) != NULL) { char buffer[1024]; while (DL_CALL_FCT (*getfct, (&entry, buffer, sizeof buffer, &errno)) == NSS_STATUS_SUCCESS) { if (entry.type == group_val) { /* Make sure we haven't seen the name before. */ struct name_list *namep; for (namep = entry.known_groups; namep != NULL; namep = namep->next) if (strcmp (entry.val.group, namep->name) == 0) break; if (namep == NULL) for (namep = entry.needed_groups; namep != NULL; namep = namep->next) if (strcmp (entry.val.group, namep->name) == 0) break; if (namep == NULL && strcmp (netgroup, entry.val.group) != 0) { size_t group_len = strlen (entry.val.group) + 1; namep = (struct name_list *) malloc (sizeof (*namep) + group_len); if (namep == NULL) { /* Out of memory, simply return. */ result = -1; break; } namep->next = entry.needed_groups; memcpy (namep->name, entry.val.group, group_len); entry.needed_groups = namep; } } else { if ((entry.val.triple.host == NULL || host == NULL || __strcasecmp (entry.val.triple.host, host) == 0) && (entry.val.triple.user == NULL || user == NULL || strcmp (entry.val.triple.user, user) == 0) && (entry.val.triple.domain == NULL || domain == NULL || __strcasecmp (entry.val.triple.domain, domain) == 0)) { result = 1; break; } } } /* If we found one service which does know the given netgroup we don't try further. */ status = NSS_STATUS_RETURN; } /* Free all resources of the service. */ endfct = __nss_lookup_function (entry.nip, "endnetgrent"); if (endfct != NULL) DL_CALL_FCT (*endfct, (&entry)); if (result != 0) break; /* Look for the next service. */ no_more = __nss_next2 (&entry.nip, "setnetgrent", NULL, &setfct.ptr, status, 0); } if (result == 0 && entry.needed_groups != NULL) { struct name_list *tmp = entry.needed_groups; entry.needed_groups = tmp->next; tmp->next = entry.known_groups; entry.known_groups = tmp; current_group = entry.known_groups->name; continue; } /* No way out. */ break; } /* Free the memory. */ free_memory (&entry); return result == 1; } libc_hidden_def (innetgr)