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Diffstat (limited to 'source3/lib/system_smbd.c')
| -rw-r--r-- | source3/lib/system_smbd.c | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/source3/lib/system_smbd.c b/source3/lib/system_smbd.c new file mode 100644 index 0000000000..1f5dd3172f --- /dev/null +++ b/source3/lib/system_smbd.c @@ -0,0 +1,198 @@ +/* + 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) != 0) { + 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(32, 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; +} |