/* 
 *  Unix SMB/CIFS implementation.
 *  RPC Pipe client / server routines
 *  Copyright (C) Andrew Tridgell              1992-1998
 *  Copyright (C) Luke Kenneth Casson Leighton 1996-1998,
 *  Copyright (C) Paul Ashton                  1997-1998.
 *  
 *  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 2 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, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*  this module apparently provides an implementation of DCE/RPC over a
 *  named pipe (IPC$ connection using SMBtrans).  details of DCE/RPC
 *  documentation are available (in on-line form) from the X-Open group.
 *
 *  this module should provide a level of abstraction between SMB
 *  and DCE/RPC, while minimising the amount of mallocs, unnecessary
 *  data copies, and network traffic.
 *
 *  in this version, which takes a "let's learn what's going on and
 *  get something running" approach, there is additional network
 *  traffic generated, but the code should be easier to understand...
 *
 *  ... if you read the docs.  or stare at packets for weeks on end.
 *
 */

#include "includes.h"

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_RPC_SRV

/*
 * A list of the rids of well known BUILTIN and Domain users
 * and groups.
 */

rid_name builtin_alias_rids[] =
{  
    { BUILTIN_ALIAS_RID_ADMINS       , "Administrators" },
    { BUILTIN_ALIAS_RID_USERS        , "Users" },
    { BUILTIN_ALIAS_RID_GUESTS       , "Guests" },
    { BUILTIN_ALIAS_RID_POWER_USERS  , "Power Users" },
   
    { BUILTIN_ALIAS_RID_ACCOUNT_OPS  , "Account Operators" },
    { BUILTIN_ALIAS_RID_SYSTEM_OPS   , "System Operators" },
    { BUILTIN_ALIAS_RID_PRINT_OPS    , "Print Operators" },
    { BUILTIN_ALIAS_RID_BACKUP_OPS   , "Backup Operators" },
    { BUILTIN_ALIAS_RID_REPLICATOR   , "Replicator" },
    { 0                             , NULL }
};

/* array lookup of well-known Domain RID users. */
rid_name domain_user_rids[] =
{  
    { DOMAIN_USER_RID_ADMIN         , "Administrator" },
    { DOMAIN_USER_RID_GUEST         , "Guest" },
    { 0                             , NULL }
};

/* array lookup of well-known Domain RID groups. */
rid_name domain_group_rids[] =
{  
    { DOMAIN_GROUP_RID_ADMINS       , "Domain Admins" },
    { DOMAIN_GROUP_RID_USERS        , "Domain Users" },
    { DOMAIN_GROUP_RID_GUESTS       , "Domain Guests" },
    { 0                             , NULL }
};

/*******************************************************************
 gets a domain user's groups
 ********************************************************************/
NTSTATUS get_alias_user_groups(TALLOC_CTX *ctx, DOM_SID *sid, int *numgroups, uint32 **prids, DOM_SID *q_sid)
{
	SAM_ACCOUNT *sam_pass=NULL;
	int i, cur_rid=0;
	gid_t gid;
	gid_t *groups = NULL;
	int num_groups;
	GROUP_MAP map;
	DOM_SID tmp_sid;
	fstring user_name;
	fstring str_domsid, str_qsid;
	uint32 rid,grid;
	uint32 *rids=NULL, *new_rids=NULL;
	gid_t winbind_gid_low, winbind_gid_high;
	BOOL ret;
	BOOL winbind_groups_exist;

	/*
	 * this code is far from perfect.
	 * first it enumerates the full /etc/group and that can be slow.
	 * second, it works only with users' SIDs
	 * whereas the day we support nested groups, it will have to
	 * support both users's SIDs and domain groups' SIDs
	 *
	 * having our own ldap backend would be so much faster !
	 * we're far from that, but hope one day ;-) JFM.
	 */

	*prids=NULL;
	*numgroups=0;

	winbind_groups_exist = lp_winbind_gid(&winbind_gid_low, &winbind_gid_high);


	DEBUG(10,("get_alias_user_groups: looking if SID %s is a member of groups in the SID domain %s\n", 
	          sid_to_string(str_qsid, q_sid), sid_to_string(str_domsid, sid)));

	pdb_init_sam(&sam_pass);
	become_root();
	ret = pdb_getsampwsid(sam_pass, q_sid);
	unbecome_root();
	if (ret == False) {
		pdb_free_sam(&sam_pass);
		return NT_STATUS_NO_SUCH_USER;
	}

	fstrcpy(user_name, pdb_get_username(sam_pass));
	grid=pdb_get_group_rid(sam_pass);
	gid=pdb_get_gid(sam_pass);

	become_root();
	/* on some systems this must run as root */
	num_groups = getgroups_user(user_name, &groups);	
	unbecome_root();
	if (num_groups == -1) {
		/* this should never happen */
		DEBUG(2,("get_alias_user_groups: getgroups_user failed\n"));
		pdb_free_sam(&sam_pass);
		return NT_STATUS_UNSUCCESSFUL;
	}

	for (i=0;i<num_groups;i++) {
		if(!get_group_from_gid(groups[i], &map, MAPPING_WITHOUT_PRIV)) {
			DEBUG(10,("get_alias_user_groups: gid %d. not found\n", (int)groups[i]));
			continue;
		}
		
		/* if it's not an alias, continue */
		if (map.sid_name_use!=SID_NAME_ALIAS) {
			DEBUG(10,("get_alias_user_groups: not returing %s, not an ALIAS group.\n", map.nt_name));
			continue;
		}

		sid_copy(&tmp_sid, &map.sid);
		sid_split_rid(&tmp_sid, &rid);
		
		/* if the sid is not in the correct domain, continue */
		if (!sid_equal(&tmp_sid, sid)) {
			DEBUG(10,("get_alias_user_groups: not returing %s, not in the domain SID.\n", map.nt_name));
			continue;
		}

		/* Don't return winbind groups as they are not local! */
		if (winbind_groups_exist && (groups[i] >= winbind_gid_low) && (groups[i] <= winbind_gid_high)) {
			DEBUG(10,("get_alias_user_groups: not returing %s, not local.\n", map.nt_name));
			continue;
		}

		/* Don't return user private groups... */
		if (Get_Pwnam(map.nt_name) != 0) {
			DEBUG(10,("get_alias_user_groups: not returing %s, clashes with user.\n", map.nt_name));
			continue;			
		}
		
		new_rids=(uint32 *)Realloc(rids, sizeof(uint32)*(cur_rid+1));
		if (new_rids==NULL) {
			DEBUG(10,("get_alias_user_groups: could not realloc memory\n"));
			pdb_free_sam(&sam_pass);
			free(groups);
			return NT_STATUS_NO_MEMORY;
		}
		rids=new_rids;
		
		sid_peek_rid(&map.sid, &(rids[cur_rid]));
		cur_rid++;
		break;
	}

	free(groups);

	/* now check for the user's gid (the primary group rid) */
	for (i=0; i<cur_rid && grid!=rids[i]; i++)
		;

	/* the user's gid is already there */
	if (i!=cur_rid) {
		DEBUG(10,("get_alias_user_groups: user is already in the list. good.\n"));
		goto done;
	}

	DEBUG(10,("get_alias_user_groups: looking for gid %d of user %s\n", (int)gid, user_name));

	if(!get_group_from_gid(gid, &map, MAPPING_WITHOUT_PRIV)) {
		DEBUG(0,("get_alias_user_groups: gid of user %s doesn't exist. Check your /etc/passwd and /etc/group files\n", user_name));
		goto done;
	}	

	/* the primary group isn't an alias */
	if (map.sid_name_use!=SID_NAME_ALIAS) {
		DEBUG(10,("get_alias_user_groups: not returing %s, not an ALIAS group.\n", map.nt_name));
		goto done;
	}

	sid_copy(&tmp_sid, &map.sid);
	sid_split_rid(&tmp_sid, &rid);

	/* if the sid is not in the correct domain, continue */
	if (!sid_equal(&tmp_sid, sid)) {
		DEBUG(10,("get_alias_user_groups: not returing %s, not in the domain SID.\n", map.nt_name));
		goto done;
	}

	/* Don't return winbind groups as they are not local! */
	if (winbind_groups_exist && (gid >= winbind_gid_low) && (gid <= winbind_gid_high)) {
		DEBUG(10,("get_alias_user_groups: not returing %s, not local.\n", map.nt_name ));
		goto done;
	}

	/* Don't return user private groups... */
	if (Get_Pwnam(map.nt_name) != 0) {
		DEBUG(10,("get_alias_user_groups: not returing %s, clashes with user.\n", map.nt_name ));
		goto done;			
	}

	new_rids=(uint32 *)Realloc(rids, sizeof(uint32)*(cur_rid+1));
	if (new_rids==NULL) {
		DEBUG(10,("get_alias_user_groups: could not realloc memory\n"));
		pdb_free_sam(&sam_pass);
		return NT_STATUS_NO_MEMORY;
	}
	rids=new_rids;

 	sid_peek_rid(&map.sid, &(rids[cur_rid]));
	cur_rid++;

done:
 	*prids=rids;
	*numgroups=cur_rid;
	pdb_free_sam(&sam_pass);

	return NT_STATUS_OK;
}


/*******************************************************************
 gets a domain user's groups
 ********************************************************************/
BOOL get_domain_user_groups(TALLOC_CTX *ctx, int *numgroups, DOM_GID **pgids, SAM_ACCOUNT *sam_pass)
{
	GROUP_MAP *map=NULL;
	int i, num, num_entries, cur_gid=0;
	struct group *grp;
	DOM_GID *gids;
	fstring user_name;
	uint32 grid;
	uint32 tmp_rid;

	*numgroups= 0;

	fstrcpy(user_name, pdb_get_username(sam_pass));
	grid=pdb_get_group_rid(sam_pass);

	DEBUG(10,("get_domain_user_groups: searching domain groups [%s] is a member of\n", user_name));

	/* first get the list of the domain groups */
	if (!enum_group_mapping(SID_NAME_DOM_GRP, &map, &num_entries, ENUM_ONLY_MAPPED, MAPPING_WITHOUT_PRIV))
		return False;
	DEBUG(10,("get_domain_user_groups: there are %d mapped groups\n", num_entries));

	/* 
	 * alloc memory. In the worse case, we alloc memory for nothing.
	 * but I prefer to alloc for nothing
	 * than reallocing everytime.
	 */
	gids = (DOM_GID *)talloc(ctx, sizeof(DOM_GID) *  num_entries);	

	/* for each group, check if the user is a member of*/
	for(i=0; i<num_entries; i++) {
		if ((grp=getgrgid(map[i].gid)) == NULL) {
			/* very weird !!! */
			DEBUG(5,("get_domain_user_groups: gid %d doesn't exist anymore !\n", (int)map[i].gid));
			continue;
		}

		for(num=0; grp->gr_mem[num]!=NULL; num++) {
			if(strcmp(grp->gr_mem[num], user_name)==0) {
				/* we found the user, add the group to the list */
				sid_peek_rid(&map[i].sid, &(gids[cur_gid].g_rid));
				gids[cur_gid].attr=7;
				DEBUG(10,("get_domain_user_groups: user found in group %s\n", map[i].nt_name));
				cur_gid++;
				break;
			}
		}
	}

	/* we have checked the groups */
	/* we must now check the gid of the user or the primary group rid, that's the same */
	for (i=0; i<cur_gid && grid!=gids[i].g_rid; i++)
		;
	
	/* the user's gid is already there */
	if (i!=cur_gid) {
		/* 
		 * the primary group of the user but be the first one in the list
		 * don't ask ! JFM.
		 */
		gids[i].g_rid=gids[0].g_rid;
		gids[0].g_rid=grid;
		goto done;
	}

	for(i=0; i<num_entries; i++) {
		sid_peek_rid(&map[i].sid, &tmp_rid);
		if (tmp_rid==grid) {
			/* 
			 * the primary group of the user but be the first one in the list
			 * don't ask ! JFM.
			 */
			gids[cur_gid].g_rid=gids[0].g_rid;
			gids[0].g_rid=tmp_rid;
			gids[cur_gid].attr=7;
			DEBUG(10,("get_domain_user_groups: primary gid of user found in group %s\n", map[i].nt_name));
			cur_gid++;
			goto done; /* leave the loop early */
		}
	}

	DEBUG(0,("get_domain_user_groups: primary gid of user [%s] is not a Domain group !\n", user_name));
	DEBUGADD(0,("get_domain_user_groups: You should fix it, NT doesn't like that\n"));

 done:
	*pgids=gids;
	*numgroups=cur_gid;
	safe_free(map);

	return True;
}

/*******************************************************************
 Look up a local (domain) rid and return a name and type.
 ********************************************************************/
NTSTATUS local_lookup_group_name(uint32 rid, char *group_name, uint32 *type)
{
	int i = 0; 
	(*type) = SID_NAME_DOM_GRP;

	DEBUG(5,("lookup_group_name: rid: %d", rid));

	while (domain_group_rids[i].rid != rid && domain_group_rids[i].rid != 0)
	{
		i++;
	}

	if (domain_group_rids[i].rid != 0)
	{
		fstrcpy(group_name, domain_group_rids[i].name);
		DEBUG(5,(" = %s\n", group_name));
		return NT_STATUS_OK;
	}

	DEBUG(5,(" none mapped\n"));
	return NT_STATUS_NONE_MAPPED;
}

/*******************************************************************
 Look up a local alias rid and return a name and type.
 ********************************************************************/
NTSTATUS local_lookup_alias_name(uint32 rid, char *alias_name, uint32 *type)
{
	int i = 0; 
	(*type) = SID_NAME_WKN_GRP;

	DEBUG(5,("lookup_alias_name: rid: %d", rid));

	while (builtin_alias_rids[i].rid != rid && builtin_alias_rids[i].rid != 0)
	{
		i++;
	}

	if (builtin_alias_rids[i].rid != 0)
	{
		fstrcpy(alias_name, builtin_alias_rids[i].name);
		DEBUG(5,(" = %s\n", alias_name));
		return NT_STATUS_OK;
	}

	DEBUG(5,(" none mapped\n"));
	return NT_STATUS_NONE_MAPPED;
}


#if 0 /*Nobody uses this function just now*/
/*******************************************************************
 Look up a local user rid and return a name and type.
 ********************************************************************/
NTSTATUS local_lookup_user_name(uint32 rid, char *user_name, uint32 *type)
{
	SAM_ACCOUNT *sampwd=NULL;
	int i = 0;
	BOOL ret;
	
	(*type) = SID_NAME_USER;

	DEBUG(5,("lookup_user_name: rid: %d", rid));

	/* look up the well-known domain user rids first */
	while (domain_user_rids[i].rid != rid && domain_user_rids[i].rid != 0)
	{
		i++;
	}

	if (domain_user_rids[i].rid != 0) {
		fstrcpy(user_name, domain_user_rids[i].name);
		DEBUG(5,(" = %s\n", user_name));
		return NT_STATUS_OK;
	}

	pdb_init_sam(&sampwd);

	/* ok, it's a user.  find the user account */
	become_root();
	ret = pdb_getsampwrid(sampwd, rid);
	unbecome_root();

	if (ret == True) {
		fstrcpy(user_name, pdb_get_username(sampwd) );
		DEBUG(5,(" = %s\n", user_name));
		pdb_free_sam(&sampwd);
		return NT_STATUS_OK;
	}

	DEBUG(5,(" none mapped\n"));
	pdb_free_sam(&sampwd);
	return NT_STATUS_NONE_MAPPED;
}

#endif

/*******************************************************************
 Look up a local (domain) group name and return a rid
 ********************************************************************/
NTSTATUS local_lookup_group_rid(char *group_name, uint32 *rid)
{
	char *grp_name;
	int i = -1; /* start do loop at -1 */

	do /* find, if it exists, a group rid for the group name*/
	{
		i++;
		(*rid) = domain_group_rids[i].rid;
		grp_name = domain_group_rids[i].name;

	} while (grp_name != NULL && !strequal(grp_name, group_name));

	return (grp_name != NULL) ? NT_STATUS_OK : NT_STATUS_NONE_MAPPED;
}

/*******************************************************************
 Look up a local (BUILTIN) alias name and return a rid
 ********************************************************************/
NTSTATUS local_lookup_alias_rid(char *alias_name, uint32 *rid)
{
	char *als_name;
	int i = -1; /* start do loop at -1 */

	do /* find, if it exists, a alias rid for the alias name*/
	{
		i++;
		(*rid) = builtin_alias_rids[i].rid;
		als_name = builtin_alias_rids[i].name;

	} while (als_name != NULL && !strequal(als_name, alias_name));

	return (als_name != NULL) ? NT_STATUS_OK : NT_STATUS_NONE_MAPPED;
}

/*******************************************************************
 Look up a local user name and return a rid
 ********************************************************************/
NTSTATUS local_lookup_user_rid(char *user_name, uint32 *rid)
{
	SAM_ACCOUNT *sampass=NULL;
	BOOL ret;

	(*rid) = 0;

	pdb_init_sam(&sampass);

	/* find the user account */
	become_root();
	ret = pdb_getsampwnam(sampass, user_name);
	unbecome_root();

	if (ret == True) {
		(*rid) = pdb_get_user_rid(sampass);
		pdb_free_sam(&sampass);
		return NT_STATUS_OK;
	}

	pdb_free_sam(&sampass);
	return NT_STATUS_NONE_MAPPED;
}