/* Unix SMB/CIFS implementation. system call wrapper interface. Copyright (C) Andrew Tridgell 2002 Copyright (C) Andrew Barteltt 2002 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ /* This file may assume linkage with smbd - for things like become_root() etc. */ #include "includes.h" #ifndef HAVE_GETGROUPLIST /* This is a *much* faster way of getting the list of groups for a user without changing the current supplementary group list. The old method used getgrent() which could take 20 minutes on a really big network with hundeds of thousands of groups and users. The new method takes a couple of seconds. NOTE!! this function only works if it is called as root! */ static int getgrouplist_internals(const char *user, gid_t gid, gid_t *groups, int *grpcnt) { gid_t *gids_saved; int ret, ngrp_saved, num_gids; if (non_root_mode()) { *grpcnt = 0; return 0; } /* work out how many groups we need to save */ ngrp_saved = getgroups(0, NULL); if (ngrp_saved == -1) { /* this shouldn't happen */ return -1; } gids_saved = SMB_MALLOC_ARRAY(gid_t, ngrp_saved+1); if (!gids_saved) { errno = ENOMEM; return -1; } ngrp_saved = getgroups(ngrp_saved, gids_saved); if (ngrp_saved == -1) { SAFE_FREE(gids_saved); /* very strange! */ return -1; } if (initgroups(user, gid) == -1) { DEBUG(0, ("getgrouplist_internals: initgroups() failed!\n")); SAFE_FREE(gids_saved); return -1; } /* this must be done to cope with systems that put the current egid in the return from getgroups() */ save_re_gid(); set_effective_gid(gid); setgid(gid); num_gids = getgroups(0, NULL); if (num_gids == -1) { SAFE_FREE(gids_saved); /* very strange! */ return -1; } if (num_gids + 1 > *grpcnt) { *grpcnt = num_gids + 1; ret = -1; } else { ret = getgroups(*grpcnt - 1, &groups[1]); if (ret < 0) { SAFE_FREE(gids_saved); /* very strange! */ return -1; } groups[0] = gid; *grpcnt = ret + 1; } restore_re_gid(); if (sys_setgroups(gid, ngrp_saved, gids_saved) != 0) { /* yikes! */ DEBUG(0,("ERROR: getgrouplist: failed to reset group list!\n")); smb_panic("getgrouplist: failed to reset group list!"); } free(gids_saved); return ret; } #endif static int sys_getgrouplist(const char *user, gid_t gid, gid_t *groups, int *grpcnt) { int retval; bool winbind_env; DEBUG(10,("sys_getgrouplist: user [%s]\n", user)); /* This is only ever called for Unix users, remote memberships are * always determined by the info3 coming back from auth3 or the * PAC. */ winbind_env = winbind_env_set(); (void)winbind_off(); #ifdef HAVE_GETGROUPLIST retval = getgrouplist(user, gid, groups, grpcnt); #else become_root(); retval = getgrouplist_internals(user, gid, groups, grpcnt); unbecome_root(); #endif /* allow winbindd lookups, but only if they were not already disabled */ if (!winbind_env) { (void)winbind_on(); } return retval; } bool getgroups_unix_user(TALLOC_CTX *mem_ctx, const char *user, gid_t primary_gid, gid_t **ret_groups, size_t *p_ngroups) { size_t ngrp; int max_grp; gid_t *temp_groups; gid_t *groups; int i; max_grp = MIN(128, groups_max()); temp_groups = SMB_MALLOC_ARRAY(gid_t, max_grp); if (! temp_groups) { return False; } if (sys_getgrouplist(user, primary_gid, temp_groups, &max_grp) == -1) { temp_groups = SMB_REALLOC_ARRAY(temp_groups, gid_t, max_grp); if (!temp_groups) { return False; } if (sys_getgrouplist(user, primary_gid, temp_groups, &max_grp) == -1) { DEBUG(0, ("get_user_groups: failed to get the unix " "group list\n")); SAFE_FREE(temp_groups); return False; } } ngrp = 0; groups = NULL; /* Add in primary group first */ if (!add_gid_to_array_unique(mem_ctx, primary_gid, &groups, &ngrp)) { SAFE_FREE(temp_groups); return False; } for (i=0; i<max_grp; i++) { if (!add_gid_to_array_unique(mem_ctx, temp_groups[i], &groups, &ngrp)) { SAFE_FREE(temp_groups); return False; } } *p_ngroups = ngrp; *ret_groups = groups; SAFE_FREE(temp_groups); return True; }