diff options
Diffstat (limited to 'nis/nss_compat/compat-initgroups.c')
| -rw-r--r-- | nis/nss_compat/compat-initgroups.c | 576 |
1 files changed, 0 insertions, 576 deletions
diff --git a/nis/nss_compat/compat-initgroups.c b/nis/nss_compat/compat-initgroups.c deleted file mode 100644 index 795213448c..0000000000 --- a/nis/nss_compat/compat-initgroups.c +++ /dev/null @@ -1,576 +0,0 @@ -/* Copyright (C) 1998-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Thorsten Kukuk <kukuk@suse.de>, 1998. - - 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, see - <http://www.gnu.org/licenses/>. */ - -#include <ctype.h> -#include <errno.h> -#include <fcntl.h> -#include <grp.h> -#include <nss.h> -#include <stdio_ext.h> -#include <string.h> -#include <unistd.h> -#include <rpc/types.h> -#include <sys/param.h> -#include <nsswitch.h> -#include <libc-lock.h> -#include <kernel-features.h> -#include <scratch_buffer.h> - -static service_user *ni; -/* Type of the lookup function. */ -static enum nss_status (*nss_initgroups_dyn) (const char *, gid_t, - long int *, long int *, - gid_t **, long int, int *); -static enum nss_status (*nss_getgrnam_r) (const char *name, - struct group * grp, char *buffer, - size_t buflen, int *errnop); -static enum nss_status (*nss_getgrgid_r) (gid_t gid, struct group * grp, - char *buffer, size_t buflen, - int *errnop); -static enum nss_status (*nss_setgrent) (int stayopen); -static enum nss_status (*nss_getgrent_r) (struct group * grp, char *buffer, - size_t buflen, int *errnop); -static enum nss_status (*nss_endgrent) (void); - -/* Protect global state against multiple changers. */ -__libc_lock_define_initialized (static, lock) - - -/* Get the declaration of the parser function. */ -#define ENTNAME grent -#define STRUCTURE group -#define EXTERN_PARSER -#include <nss/nss_files/files-parse.c> - -/* Structure for remembering -group members ... */ -#define BLACKLIST_INITIAL_SIZE 512 -#define BLACKLIST_INCREMENT 256 -struct blacklist_t -{ - char *data; - int current; - int size; -}; - -struct ent_t -{ - bool files; - bool need_endgrent; - bool skip_initgroups_dyn; - FILE *stream; - struct blacklist_t blacklist; -}; -typedef struct ent_t ent_t; - -/* Prototypes for local functions. */ -static void blacklist_store_name (const char *, ent_t *); -static int in_blacklist (const char *, int, ent_t *); - -/* Initialize the NSS interface/functions. The calling function must - hold the lock. */ -static void -init_nss_interface (void) -{ - __libc_lock_lock (lock); - - /* Retest. */ - if (ni == NULL - && __nss_database_lookup ("group_compat", NULL, "nis", &ni) >= 0) - { - nss_initgroups_dyn = __nss_lookup_function (ni, "initgroups_dyn"); - nss_getgrnam_r = __nss_lookup_function (ni, "getgrnam_r"); - nss_getgrgid_r = __nss_lookup_function (ni, "getgrgid_r"); - nss_setgrent = __nss_lookup_function (ni, "setgrent"); - nss_getgrent_r = __nss_lookup_function (ni, "getgrent_r"); - nss_endgrent = __nss_lookup_function (ni, "endgrent"); - } - - __libc_lock_unlock (lock); -} - -static enum nss_status -internal_setgrent (ent_t *ent) -{ - enum nss_status status = NSS_STATUS_SUCCESS; - - ent->files = true; - - if (ni == NULL) - init_nss_interface (); - - if (ent->blacklist.data != NULL) - { - ent->blacklist.current = 1; - ent->blacklist.data[0] = '|'; - ent->blacklist.data[1] = '\0'; - } - else - ent->blacklist.current = 0; - - ent->stream = fopen ("/etc/group", "rme"); - - if (ent->stream == NULL) - status = errno == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL; - else - /* We take care of locking ourself. */ - __fsetlocking (ent->stream, FSETLOCKING_BYCALLER); - - return status; -} - - -static enum nss_status -internal_endgrent (ent_t *ent) -{ - if (ent->stream != NULL) - { - fclose (ent->stream); - ent->stream = NULL; - } - - if (ent->blacklist.data != NULL) - { - ent->blacklist.current = 1; - ent->blacklist.data[0] = '|'; - ent->blacklist.data[1] = '\0'; - } - else - ent->blacklist.current = 0; - - if (ent->need_endgrent && nss_endgrent != NULL) - nss_endgrent (); - - return NSS_STATUS_SUCCESS; -} - -/* Add new group record. */ -static void -add_group (long int *start, long int *size, gid_t **groupsp, long int limit, - gid_t gid) -{ - gid_t *groups = *groupsp; - - /* Matches user. Insert this group. */ - if (__glibc_unlikely (*start == *size)) - { - /* Need a bigger buffer. */ - gid_t *newgroups; - long int newsize; - - if (limit > 0 && *size == limit) - /* We reached the maximum. */ - return; - - if (limit <= 0) - newsize = 2 * *size; - else - newsize = MIN (limit, 2 * *size); - - newgroups = realloc (groups, newsize * sizeof (*groups)); - if (newgroups == NULL) - return; - *groupsp = groups = newgroups; - *size = newsize; - } - - groups[*start] = gid; - *start += 1; -} - -/* This function checks, if the user is a member of this group and if - yes, add the group id to the list. Return nonzero is we couldn't - handle the group because the user is not in the member list. */ -static int -check_and_add_group (const char *user, gid_t group, long int *start, - long int *size, gid_t **groupsp, long int limit, - struct group *grp) -{ - char **member; - - /* Don't add main group to list of groups. */ - if (grp->gr_gid == group) - return 0; - - for (member = grp->gr_mem; *member != NULL; ++member) - if (strcmp (*member, user) == 0) - { - add_group (start, size, groupsp, limit, grp->gr_gid); - return 0; - } - - return 1; -} - -/* Get the next group from NSS (+ entry). If the NSS module supports - initgroups_dyn, get all entries at once. */ -static enum nss_status -getgrent_next_nss (ent_t *ent, char *buffer, size_t buflen, const char *user, - gid_t group, long int *start, long int *size, - gid_t **groupsp, long int limit, int *errnop) -{ - enum nss_status status; - struct group grpbuf; - - /* Try nss_initgroups_dyn if supported. We also need getgrgid_r. - If this function is not supported, step through the whole group - database with getgrent_r. */ - if (! ent->skip_initgroups_dyn) - { - long int mystart = 0; - long int mysize = limit <= 0 ? *size : limit; - gid_t *mygroups = malloc (mysize * sizeof (gid_t)); - - if (mygroups == NULL) - return NSS_STATUS_TRYAGAIN; - - /* For every gid in the list we get from the NSS module, - get the whole group entry. We need to do this, since we - need the group name to check if it is in the blacklist. - In worst case, this is as twice as slow as stepping with - getgrent_r through the whole group database. But for large - group databases this is faster, since the user can only be - in a limited number of groups. */ - if (nss_initgroups_dyn (user, group, &mystart, &mysize, &mygroups, - limit, errnop) == NSS_STATUS_SUCCESS) - { - status = NSS_STATUS_NOTFOUND; - - /* If there is no blacklist we can trust the underlying - initgroups implementation. */ - if (ent->blacklist.current <= 1) - for (int i = 0; i < mystart; i++) - add_group (start, size, groupsp, limit, mygroups[i]); - else - { - /* A temporary buffer. We use the normal buffer, until we find - an entry, for which this buffer is to small. In this case, we - overwrite the pointer with one to a bigger buffer. */ - char *tmpbuf = buffer; - size_t tmplen = buflen; - bool use_malloc = false; - - for (int i = 0; i < mystart; i++) - { - while ((status = nss_getgrgid_r (mygroups[i], &grpbuf, - tmpbuf, tmplen, errnop)) - == NSS_STATUS_TRYAGAIN - && *errnop == ERANGE) - { - if (__libc_use_alloca (tmplen * 2)) - { - if (tmpbuf == buffer) - { - tmplen *= 2; - tmpbuf = __alloca (tmplen); - } - else - tmpbuf = extend_alloca (tmpbuf, tmplen, tmplen * 2); - } - else - { - tmplen *= 2; - char *newbuf = realloc (use_malloc ? tmpbuf : NULL, tmplen); - - if (newbuf == NULL) - { - status = NSS_STATUS_TRYAGAIN; - goto done; - } - use_malloc = true; - tmpbuf = newbuf; - } - } - - if (__builtin_expect (status != NSS_STATUS_NOTFOUND, 1)) - { - if (__builtin_expect (status != NSS_STATUS_SUCCESS, 0)) - goto done; - - if (!in_blacklist (grpbuf.gr_name, - strlen (grpbuf.gr_name), ent) - && check_and_add_group (user, group, start, size, - groupsp, limit, &grpbuf)) - { - if (nss_setgrent != NULL) - { - nss_setgrent (1); - ent->need_endgrent = true; - } - ent->skip_initgroups_dyn = true; - - goto iter; - } - } - } - - status = NSS_STATUS_NOTFOUND; - - done: - if (use_malloc) - free (tmpbuf); - } - - free (mygroups); - - return status; - } - - free (mygroups); - } - - /* If we come here, the NSS module does not support initgroups_dyn - or we were confronted with a split group. In these cases we have - to step through the whole list ourself. */ - iter: - do - { - if ((status = nss_getgrent_r (&grpbuf, buffer, buflen, errnop)) != - NSS_STATUS_SUCCESS) - break; - } - while (in_blacklist (grpbuf.gr_name, strlen (grpbuf.gr_name), ent)); - - if (status == NSS_STATUS_SUCCESS) - check_and_add_group (user, group, start, size, groupsp, limit, &grpbuf); - - return status; -} - -static enum nss_status -internal_getgrent_r (ent_t *ent, char *buffer, size_t buflen, const char *user, - gid_t group, long int *start, long int *size, - gid_t **groupsp, long int limit, int *errnop) -{ - struct parser_data *data = (void *) buffer; - struct group grpbuf; - - if (!ent->files) - return getgrent_next_nss (ent, buffer, buflen, user, group, - start, size, groupsp, limit, errnop); - - while (1) - { - fpos_t pos; - int parse_res = 0; - char *p; - - do - { - /* We need at least 3 characters for one line. */ - if (__glibc_unlikely (buflen < 3)) - { - erange: - *errnop = ERANGE; - return NSS_STATUS_TRYAGAIN; - } - - fgetpos (ent->stream, &pos); - buffer[buflen - 1] = '\xff'; - p = fgets_unlocked (buffer, buflen, ent->stream); - if (p == NULL && feof_unlocked (ent->stream)) - return NSS_STATUS_NOTFOUND; - - if (p == NULL || __builtin_expect (buffer[buflen - 1] != '\xff', 0)) - { - erange_reset: - fsetpos (ent->stream, &pos); - goto erange; - } - - /* Terminate the line for any case. */ - buffer[buflen - 1] = '\0'; - - /* Skip leading blanks. */ - while (isspace (*p)) - ++p; - } - while (*p == '\0' || *p == '#' || /* Ignore empty and comment lines. */ - /* Parse the line. If it is invalid, loop to - get the next line of the file to parse. */ - !(parse_res = _nss_files_parse_grent (p, &grpbuf, data, buflen, - errnop))); - - if (__glibc_unlikely (parse_res == -1)) - /* The parser ran out of space. */ - goto erange_reset; - - if (grpbuf.gr_name[0] != '+' && grpbuf.gr_name[0] != '-') - /* This is a real entry. */ - break; - - /* -group */ - if (grpbuf.gr_name[0] == '-' && grpbuf.gr_name[1] != '\0' - && grpbuf.gr_name[1] != '@') - { - blacklist_store_name (&grpbuf.gr_name[1], ent); - continue; - } - - /* +group */ - if (grpbuf.gr_name[0] == '+' && grpbuf.gr_name[1] != '\0' - && grpbuf.gr_name[1] != '@') - { - if (in_blacklist (&grpbuf.gr_name[1], - strlen (&grpbuf.gr_name[1]), ent)) - continue; - /* Store the group in the blacklist for the "+" at the end of - /etc/group */ - blacklist_store_name (&grpbuf.gr_name[1], ent); - if (nss_getgrnam_r == NULL) - return NSS_STATUS_UNAVAIL; - else if (nss_getgrnam_r (&grpbuf.gr_name[1], &grpbuf, buffer, - buflen, errnop) != NSS_STATUS_SUCCESS) - continue; - - check_and_add_group (user, group, start, size, groupsp, - limit, &grpbuf); - - return NSS_STATUS_SUCCESS; - } - - /* +:... */ - if (grpbuf.gr_name[0] == '+' && grpbuf.gr_name[1] == '\0') - { - /* If the selected module does not support getgrent_r or - initgroups_dyn, abort. We cannot find the needed group - entries. */ - if (nss_initgroups_dyn == NULL || nss_getgrgid_r == NULL) - { - if (nss_setgrent != NULL) - { - nss_setgrent (1); - ent->need_endgrent = true; - } - ent->skip_initgroups_dyn = true; - - if (nss_getgrent_r == NULL) - return NSS_STATUS_UNAVAIL; - } - - ent->files = false; - - return getgrent_next_nss (ent, buffer, buflen, user, group, - start, size, groupsp, limit, errnop); - } - } - - check_and_add_group (user, group, start, size, groupsp, limit, &grpbuf); - - return NSS_STATUS_SUCCESS; -} - - -enum nss_status -_nss_compat_initgroups_dyn (const char *user, gid_t group, long int *start, - long int *size, gid_t **groupsp, long int limit, - int *errnop) -{ - enum nss_status status; - ent_t intern = { true, false, false, NULL, {NULL, 0, 0} }; - - status = internal_setgrent (&intern); - if (status != NSS_STATUS_SUCCESS) - return status; - - struct scratch_buffer tmpbuf; - scratch_buffer_init (&tmpbuf); - - do - { - while ((status = internal_getgrent_r (&intern, tmpbuf.data, tmpbuf.length, - user, group, start, size, - groupsp, limit, errnop)) - == NSS_STATUS_TRYAGAIN && *errnop == ERANGE) - if (!scratch_buffer_grow (&tmpbuf)) - goto done; - } - while (status == NSS_STATUS_SUCCESS); - - status = NSS_STATUS_SUCCESS; - - done: - scratch_buffer_free (&tmpbuf); - - internal_endgrent (&intern); - - return status; -} - - -/* Support routines for remembering -@netgroup and -user entries. - The names are stored in a single string with `|' as separator. */ -static void -blacklist_store_name (const char *name, ent_t *ent) -{ - int namelen = strlen (name); - char *tmp; - - /* First call, setup cache. */ - if (ent->blacklist.size == 0) - { - ent->blacklist.size = MAX (BLACKLIST_INITIAL_SIZE, 2 * namelen); - ent->blacklist.data = malloc (ent->blacklist.size); - if (ent->blacklist.data == NULL) - return; - ent->blacklist.data[0] = '|'; - ent->blacklist.data[1] = '\0'; - ent->blacklist.current = 1; - } - else - { - if (in_blacklist (name, namelen, ent)) - return; /* no duplicates */ - - if (ent->blacklist.current + namelen + 1 >= ent->blacklist.size) - { - ent->blacklist.size += MAX (BLACKLIST_INCREMENT, 2 * namelen); - tmp = realloc (ent->blacklist.data, ent->blacklist.size); - if (tmp == NULL) - { - free (ent->blacklist.data); - ent->blacklist.size = 0; - return; - } - ent->blacklist.data = tmp; - } - } - - tmp = stpcpy (ent->blacklist.data + ent->blacklist.current, name); - *tmp++ = '|'; - *tmp = '\0'; - ent->blacklist.current += namelen + 1; - - return; -} - -/* returns TRUE if ent->blacklist contains name, else FALSE */ -static bool_t -in_blacklist (const char *name, int namelen, ent_t *ent) -{ - char buf[namelen + 3]; - char *cp; - - if (ent->blacklist.data == NULL) - return FALSE; - - buf[0] = '|'; - cp = stpcpy (&buf[1], name); - *cp++ = '|'; - *cp = '\0'; - return strstr (ent->blacklist.data, buf) != NULL; -} |