/* * IPv6 fragment reassembly * Linux INET6 implementation * * Authors: * Pedro Roque * * $Id: reassembly.c,v 1.26 2001/03/07 22:00:57 davem Exp $ * * Based on: net/ipv4/ip_fragment.c * * 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. */ /* * Fixes: * Andi Kleen Make it work with multiple hosts. * More RFC compliance. * * Horst von Brand Add missing #include * Alexey Kuznetsov SMP races, threading, cleanup. * Patrick McHardy LRU queue of frag heads for evictor. * Mitsuru KANDA @USAGI Register inet6_protocol{}. * David Stevens and * YOSHIFUJI,H. @USAGI Always remove fragment header to * calculate ICV correctly. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include int sysctl_ip6frag_high_thresh __read_mostly = 256*1024; int sysctl_ip6frag_low_thresh __read_mostly = 192*1024; int sysctl_ip6frag_time __read_mostly = IPV6_FRAG_TIMEOUT; struct ip6frag_skb_cb { struct inet6_skb_parm h; int offset; }; #define FRAG6_CB(skb) ((struct ip6frag_skb_cb*)((skb)->cb)) /* * Equivalent of ipv4 struct ipq */ struct frag_queue { struct hlist_node list; struct list_head lru_list; /* lru list member */ __be32 id; /* fragment id */ struct in6_addr saddr; struct in6_addr daddr; spinlock_t lock; atomic_t refcnt; struct timer_list timer; /* expire timer */ struct sk_buff *fragments; int len; int meat; int iif; struct timeval stamp; unsigned int csum; __u8 last_in; /* has first/last segment arrived? */ #define COMPLETE 4 #define FIRST_IN 2 #define LAST_IN 1 __u16 nhoffset; }; /* Hash table. */ #define IP6Q_HASHSZ 64 static struct hlist_head ip6_frag_hash[IP6Q_HASHSZ]; static DEFINE_RWLOCK(ip6_frag_lock); static u32 ip6_frag_hash_rnd; static LIST_HEAD(ip6_frag_lru_list); int ip6_frag_nqueues = 0; static __inline__ void __fq_unlink(struct frag_queue *fq) { hlist_del(&fq->list); list_del(&fq->lru_list); ip6_frag_nqueues--; } static __inline__ void fq_unlink(struct frag_queue *fq) { write_lock(&ip6_frag_lock); __fq_unlink(fq); write_unlock(&ip6_frag_lock); } /* * callers should be careful not to use the hash value outside the ipfrag_lock * as doing so could race with ipfrag_hash_rnd being recalculated. */ static unsigned int ip6qhashfn(__be32 id, struct in6_addr *saddr, struct in6_addr *daddr) { u32 a, b, c; a = (__force u32)saddr->s6_addr32[0]; b = (__force u32)saddr->s6_addr32[1]; c = (__force u32)saddr->s6_addr32[2]; a += JHASH_GOLDEN_RATIO; b += JHASH_GOLDEN_RATIO; c += ip6_frag_hash_rnd; __jhash_mix(a, b, c); a += (__force u32)saddr->s6_addr32[3]; b += (__force u32)daddr->s6_addr32[0]; c += (__force u32)daddr->s6_addr32[1]; __jhash_mix(a, b, c); a += (__force u32)daddr->s6_addr32[2]; b += (__force u32)daddr->s6_addr32[3]; c += (__force u32)id; __jhash_mix(a, b, c); return c & (IP6Q_HASHSZ - 1); } static struct timer_list ip6_frag_secret_timer; int sysctl_ip6frag_secret_interval __read_mostly = 10 * 60 * HZ; static void ip6_frag_secret_rebuild(unsigned long dummy) { unsigned long now = jiffies; int i; write_lock(&ip6_frag_lock); get_random_bytes(&ip6_frag_hash_rnd, sizeof(u32)); for (i = 0; i < IP6Q_HASHSZ; i++) { struct frag_queue *q; struct hlist_node *p, *n; hlist_for_each_entry_safe(q, p, n, &ip6_frag_hash[i], list) { unsigned int hval = ip6qhashfn(q->id, &q->saddr, &q->daddr); if (hval != i) { hlist_del(&q->list); /* Relink to new hash chain. */ hlist_add_head(&q->list, &ip6_frag_hash[hval]); } } } write_unlock(&ip6_frag_lock); mod_timer(&ip6_frag_secret_timer, now + sysctl_ip6frag_secret_interval); } atomic_t ip6_frag_mem = ATOMIC_INIT(0); /* Memory Tracking Functions. */ static inline void frag_kfree_skb(struct sk_buff *skb, int *work) { if (work) *work -= skb->truesize; atomic_sub(skb->truesize, &ip6_frag_mem); kfree_skb(skb); } static inline void frag_free_queue(struct frag_queue *fq, int *work) { if (work) *work -= sizeof(struct frag_queue); atomic_sub(sizeof(struct frag_queue), &ip6_frag_mem); kfree(fq); } static inline struct frag_queue *frag_alloc_queue(void) { struct frag_queue *fq = kzalloc(sizeof(struct frag_queue), GFP_ATOMIC); if(!fq) return NULL; atomic_add(sizeof(struct frag_queue), &ip6_frag_mem); return fq; } /* Destruction primitives. */ /* Complete destruction of fq. */ static void ip6_frag_destroy(struct frag_queue *fq, int *work) { struct sk_buff *fp; BUG_TRAP(fq->last_in&COMPLETE); BUG_TRAP(del_timer(&fq->timer) == 0); /* Release all fragment data. */ fp = fq->fragments; while (fp) { struct sk_buff *xp = fp->next; frag_kfree_skb(fp, work); fp = xp; } frag_free_queue(fq, work); } static __inline__ void fq_put(struct frag_queue *fq, int *work) { if (atomic_dec_and_test(&fq->refcnt)) ip6_frag_destroy(fq, work); } /* Kill fq entry. It is not destroyed immediately, * because caller (and someone more) holds reference count. */ static __inline__ void fq_kill(struct frag_queue *fq) { if (del_timer(&fq->timer)) atomic_dec(&fq->refcnt); if (!(fq->last_in & COMPLETE)) { fq_unlink(fq); atomic_dec(&fq->refcnt); fq->last_in |= COMPLETE; } } static void ip6_evictor(struct inet6_dev *idev) { struct frag_queue *fq; struct list_head *tmp; int work; work = atomic_read(&ip6_frag_mem) - sysctl_ip6frag_low_thresh; if (work <= 0) return; while(work > 0) { read_lock(&ip6_frag_lock); if (list_empty(&ip6_frag_lru_list)) { read_unlock(&ip6_frag_lock); return; } tmp = ip6_frag_lru_list.next; fq = list_entry(tmp, struct frag_queue, lru_list); atomic_inc(&fq->refcnt); read_unlock(&ip6_frag_lock); spin_lock(&fq->lock); if (!(fq->last_in&COMPLETE)) fq_kill(fq); spin_unlock(&fq->lock); fq_put(fq, &work); IP6_INC_STATS_BH(idev, IPSTATS_MIB_REASMFAILS); } } static void ip6_frag_expire(unsigned long data) { struct frag_queue *fq = (struct frag_queue *) data; struct net_device *dev = NULL; spin_lock(&fq->lock); if (fq->last_in & COMPLETE) goto out; fq_kill(fq); dev = dev_get_by_index(fq->iif); if (!dev) goto out; rcu_read_lock(); IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMTIMEOUT); IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMFAILS); rcu_read_unlock(); /* Don't send error if the first segment did not arrive. */ if (!(fq->last_in&FIRST_IN) || !fq->fragments) goto out; /* But use as source device on which LAST ARRIVED segment was received. And do not use fq->dev pointer directly, device might already disappeared. */ fq->fragments->dev = dev; icmpv6_send(fq->fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0, dev); out: if (dev) dev_put(dev); spin_unlock(&fq->lock); fq_put(fq, NULL); } /* Creation primitives. */ static struct frag_queue *ip6_frag_intern(struct frag_queue *fq_in) { struct frag_queue *fq; unsigned int hash; #ifdef CONFIG_SMP struct hlist_node *n; #endif write_lock(&ip6_frag_lock); hash = ip6qhashfn(fq_in->id, &fq_in->saddr, &fq_in->daddr); #ifdef CONFIG_SMP hlist_for_each_entry(fq, n, &ip6_frag_hash[hash], list) { if (fq->id == fq_in->id && ipv6_addr_equal(&fq_in->saddr, &fq->saddr) && ipv6_addr_equal(&fq_in->daddr, &fq->daddr)) { atomic_inc(&fq->refcnt); write_unlock(&ip6_frag_lock); fq_in->last_in |= COMPLETE; fq_put(fq_in, NULL); return fq; } } #endif fq = fq_in; if (!mod_timer(&fq->timer, jiffies + sysctl_ip6frag_time)) atomic_inc(&fq->refcnt); atomic_inc(&fq->refcnt); hlist_add_head(&fq->list, &ip6_frag_hash[hash]); INIT_LIST_HEAD(&fq->lru_list); list_add_tail(&fq->lru_list, &ip6_frag_lru_list); ip6_frag_nqueues++; write_unlock(&ip6_frag_lock); return fq; } static struct frag_queue * ip6_frag_create(__be32 id, struct in6_addr *src, struct in6_addr *dst, struct inet6_dev *idev) { struct frag_queue *fq; if ((fq = frag_alloc_queue()) == NULL) goto oom; fq->id = id; ipv6_addr_copy(&fq->saddr, src); ipv6_addr_copy(&fq->daddr, dst); init_timer(&fq->timer); fq->timer.function = ip6_frag_expire; fq->timer.data = (long) fq; spin_lock_init(&fq->lock); atomic_set(&fq->refcnt, 1); return ip6_frag_intern(fq); oom: IP6_INC_STATS_BH(idev, IPSTATS_MIB_REASMFAILS); return NULL; } static __inline__ struct frag_queue * fq_find(__be32 id, struct in6_addr *src, struct in6_addr *dst, struct inet6_dev *idev) { struct frag_queue *fq; struct hlist_node *n; unsigned int hash; read_lock(&ip6_frag_lock); hash = ip6qhashfn(id, src, dst); hlist_for_each_entry(fq, n, &ip6_frag_hash[hash], list) { if (fq->id == id && ipv6_addr_equal(src, &fq->saddr) && ipv6_addr_equal(dst, &fq->daddr)) { atomic_inc(&fq->refcnt); read_unlock(&ip6_frag_lock); return fq; } } read_unlock(&ip6_frag_lock); return ip6_frag_create(id, src, dst, idev); } static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, struct frag_hdr *fhdr, int nhoff) { struct sk_buff *prev, *next; int offset, end; if (fq->last_in & COMPLETE) goto err; offset = ntohs(fhdr->frag_off) & ~0x7; end = offset + (ntohs(skb->nh.ipv6h->payload_len) - ((u8 *) (fhdr + 1) - (u8 *) (skb->nh.ipv6h + 1))); if ((unsigned int)end > IPV6_MAXPLEN) { IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb,ICMPV6_HDR_FIELD, (u8*)&fhdr->frag_off - skb->nh.raw); return; } if (skb->ip_summed == CHECKSUM_COMPLETE) skb->csum = csum_sub(skb->csum, csum_partial(skb->nh.raw, (u8*)(fhdr+1)-skb->nh.raw, 0)); /* Is this the final fragment? */ if (!(fhdr->frag_off & htons(IP6_MF))) { /* If we already have some bits beyond end * or have different end, the segment is corrupted. */ if (end < fq->len || ((fq->last_in & LAST_IN) && end != fq->len)) goto err; fq->last_in |= LAST_IN; fq->len = end; } else { /* Check if the fragment is rounded to 8 bytes. * Required by the RFC. */ if (end & 0x7) { /* RFC2460 says always send parameter problem in * this case. -DaveM */ IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, offsetof(struct ipv6hdr, payload_len)); return; } if (end > fq->len) { /* Some bits beyond end -> corruption. */ if (fq->last_in & LAST_IN) goto err; fq->len = end; } } if (end == offset) goto err; /* Point into the IP datagram 'data' part. */ if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) goto err; if (pskb_trim_rcsum(skb, end - offset)) goto err; /* Find out which fragments are in front and at the back of us * in the chain of fragments so far. We must know where to put * this fragment, right? */ prev = NULL; for(next = fq->fragments; next != NULL; next = next->next) { if (FRAG6_CB(next)->offset >= offset) break; /* bingo! */ prev = next; } /* We found where to put this one. Check for overlap with * preceding fragment, and, if needed, align things so that * any overlaps are eliminated. */ if (prev) { int i = (FRAG6_CB(prev)->offset + prev->len) - offset; if (i > 0) { offset += i; if (end <= offset) goto err; if (!pskb_pull(skb, i)) goto err; if (skb->ip_summed != CHECKSUM_UNNECESSARY) skb->ip_summed = CHECKSUM_NONE; } } /* Look for overlap with succeeding segments. * If we can merge fragments, do it. */ while (next && FRAG6_CB(next)->offset < end) { int i = end - FRAG6_CB(next)->offset; /* overlap is 'i' bytes */ if (i < next->len) { /* Eat head of the next overlapped fragment * and leave the loop. The next ones cannot overlap. */ if (!pskb_pull(next, i)) goto err; FRAG6_CB(next)->offset += i; /* next fragment */ fq->meat -= i; if (next->ip_summed != CHECKSUM_UNNECESSARY) next->ip_summed = CHECKSUM_NONE; break; } else { struct sk_buff *free_it = next; /* Old fragment is completely overridden with * new one drop it. */ next = next->next; if (prev) prev->next = next; else fq->fragments = next; fq->meat -= free_it->len; frag_kfree_skb(free_it, NULL); } } FRAG6_CB(skb)->offset = offset; /* Insert this fragment in the chain of fragments. */ skb->next = next; if (prev) prev->next = skb; else fq->fragments = skb; if (skb->dev) fq->iif = skb->dev->ifindex; skb->dev = NULL; skb_get_timestamp(skb, &fq->stamp); fq->meat += skb->len; atomic_add(skb->truesize, &ip6_frag_mem); /* The first fragment. * nhoffset is obtained from the first fragment, of course. */ if (offset == 0) { fq->nhoffset = nhoff; fq->last_in |= FIRST_IN; } write_lock(&ip6_frag_lock); list_move_tail(&fq->lru_list, &ip6_frag_lru_list); write_unlock(&ip6_frag_lock); return; err: IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMFAILS); kfree_skb(skb); } /* * Check if this packet is complete. * Returns NULL on failure by any reason, and pointer * to current nexthdr field in reassembled frame. * * It is called with locked fq, and caller must check that * queue is eligible for reassembly i.e. it is not COMPLETE, * the last and the first frames arrived and all the bits are here. */ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in, struct net_device *dev) { struct sk_buff *fp, *head = fq->fragments; int payload_len; unsigned int nhoff; fq_kill(fq); BUG_TRAP(head != NULL); BUG_TRAP(FRAG6_CB(head)->offset == 0); /* Unfragmented part is taken from the first segment. */ payload_len = (head->data - head->nh.raw) - sizeof(struct ipv6hdr) + fq->len - sizeof(struct frag_hdr); if (payload_len > IPV6_MAXPLEN) goto out_oversize; /* Head of list must not be cloned. */ if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) goto out_oom; /* If the first fragment is fragmented itself, we split * it to two chunks: the first with data and paged part * and the second, holding only fragments. */ if (skb_shinfo(head)->frag_list) { struct sk_buff *clone; int i, plen = 0; if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) goto out_oom; clone->next = head->next; head->next = clone; skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; skb_shinfo(head)->frag_list = NULL; for (i=0; inr_frags; i++) plen += skb_shinfo(head)->frags[i].size; clone->len = clone->data_len = head->data_len - plen; head->data_len -= clone->len; head->len -= clone->len; clone->csum = 0; clone->ip_summed = head->ip_summed; atomic_add(clone->truesize, &ip6_frag_mem); } /* We have to remove fragment header from datagram and to relocate * header in order to calculate ICV correctly. */ nhoff = fq->nhoffset; head->nh.raw[nhoff] = head->h.raw[0]; memmove(head->head + sizeof(struct frag_hdr), head->head, (head->data - head->head) - sizeof(struct frag_hdr)); head->mac.raw += sizeof(struct frag_hdr); head->nh.raw += sizeof(struct frag_hdr); skb_shinfo(head)->frag_list = head->next; head->h.raw = head->data; skb_push(head, head->data - head->nh.raw); atomic_sub(head->truesize, &ip6_frag_mem); for (fp=head->next; fp; fp = fp->next) { head->data_len += fp->len; head->len += fp->len; if (head->ip_summed != fp->ip_summed) head->ip_summed = CHECKSUM_NONE; else if (head->ip_summed == CHECKSUM_COMPLETE) head->csum = csum_add(head->csum, fp->csum); head->truesize += fp->truesize; atomic_sub(fp->truesize, &ip6_frag_mem); } head->next = NULL; head->dev = dev; skb_set_timestamp(head, &fq->stamp); head->nh.ipv6h->payload_len = htons(payload_len); IP6CB(head)->nhoff = nhoff; *skb_in = head; /* Yes, and fold redundant checksum back. 8) */ if (head->ip_summed == CHECKSUM_COMPLETE) head->csum = csum_partial(head->nh.raw, head->h.raw-head->nh.raw, head->csum); rcu_read_lock(); IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMOKS); rcu_read_unlock(); fq->fragments = NULL; return 1; out_oversize: if (net_ratelimit()) printk(KERN_DEBUG "ip6_frag_reasm: payload len = %d\n", payload_len); goto out_fail; out_oom: if (net_ratelimit()) printk(KERN_DEBUG "ip6_frag_reasm: no memory for reassembly\n"); out_fail: rcu_read_lock(); IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMFAILS); rcu_read_unlock(); return -1; } static int ipv6_frag_rcv(struct sk_buff **skbp) { struct sk_buff *skb = *skbp; struct net_device *dev = skb->dev; struct frag_hdr *fhdr; struct frag_queue *fq; struct ipv6hdr *hdr; hdr = skb->nh.ipv6h; IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMREQDS); /* Jumbo payload inhibits frag. header */ if (hdr->payload_len==0) { IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, skb->h.raw-skb->nh.raw); return -1; } if (!pskb_may_pull(skb, (skb->h.raw-skb->data)+sizeof(struct frag_hdr))) { IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, skb->h.raw-skb->nh.raw); return -1; } hdr = skb->nh.ipv6h; fhdr = (struct frag_hdr *)skb->h.raw; if (!(fhdr->frag_off & htons(0xFFF9))) { /* It is not a fragmented frame */ skb->h.raw += sizeof(struct frag_hdr); IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMOKS); IP6CB(skb)->nhoff = (u8*)fhdr - skb->nh.raw; return 1; } if (atomic_read(&ip6_frag_mem) > sysctl_ip6frag_high_thresh) ip6_evictor(ip6_dst_idev(skb->dst)); if ((fq = fq_find(fhdr->identification, &hdr->saddr, &hdr->daddr, ip6_dst_idev(skb->dst))) != NULL) { int ret = -1; spin_lock(&fq->lock); ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff); if (fq->last_in == (FIRST_IN|LAST_IN) && fq->meat == fq->len) ret = ip6_frag_reasm(fq, skbp, dev); spin_unlock(&fq->lock); fq_put(fq, NULL); return ret; } IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMFAILS); kfree_skb(skb); return -1; } static struct inet6_protocol frag_protocol = { .handler = ipv6_frag_rcv, .flags = INET6_PROTO_NOPOLICY, }; void __init ipv6_frag_init(void) { if (inet6_add_protocol(&frag_protocol, IPPROTO_FRAGMENT) < 0) printk(KERN_ERR "ipv6_frag_init: Could not register protocol\n"); ip6_frag_hash_rnd = (u32) ((num_physpages ^ (num_physpages>>7)) ^ (jiffies ^ (jiffies >> 6))); init_timer(&ip6_frag_secret_timer); ip6_frag_secret_timer.function = ip6_frag_secret_rebuild; ip6_frag_secret_timer.expires = jiffies + sysctl_ip6frag_secret_interval; add_timer(&ip6_frag_secret_timer); } 9' href='#n459'>459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 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# Unix SMB/CIFS implementation.
# backend code for provisioning a Samba4 server

# Copyright (C) Jelmer Vernooij <jelmer@samba.org> 2007-2010
# Copyright (C) Andrew Bartlett <abartlet@samba.org> 2008-2009
# Copyright (C) Oliver Liebel <oliver@itc.li> 2008-2009
#
# Based on the original in EJS:
# Copyright (C) Andrew Tridgell <tridge@samba.org> 2005
#
# 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/>.
#

"""Functions for setting up a Samba configuration."""

from base64 import b64encode
import os
import re
import pwd
import grp
import logging
import time
import uuid
import socket
import urllib
import shutil

import ldb

from samba.auth import system_session, admin_session
import samba
from samba import version, Ldb, substitute_var, valid_netbios_name
from samba import check_all_substituted, read_and_sub_file, setup_file
from samba.dsdb import DS_DOMAIN_FUNCTION_2003, DS_DOMAIN_FUNCTION_2008_R2, ENC_ALL_TYPES
from samba.dcerpc import security
from samba.dcerpc.misc import SEC_CHAN_BDC, SEC_CHAN_WKSTA
from samba.idmap import IDmapDB
from samba.ms_display_specifiers import read_ms_ldif
from samba.ntacls import setntacl, dsacl2fsacl
from samba.ndr import ndr_pack,ndr_unpack
from samba.provisionbackend import (
    ExistingBackend,
    FDSBackend,
    LDBBackend,
    OpenLDAPBackend,
    )
import samba.param
import samba.registry
from samba.schema import Schema
from samba.samdb import SamDB

__docformat__ = "restructuredText"
DEFAULT_POLICY_GUID = "31B2F340-016D-11D2-945F-00C04FB984F9"
DEFAULT_DC_POLICY_GUID = "6AC1786C-016F-11D2-945F-00C04fB984F9"

def find_setup_dir():
    """Find the setup directory used by provision."""
    import sys
    for prefix in [sys.prefix,
            os.path.join(os.path.dirname(__file__), "../../../..")]:
        for suffix in ["share/setup", "share/samba/setup", "setup"]:
            ret = os.path.join(prefix, suffix)
            if os.path.isdir(ret):
                return ret
    # In source tree
    dirname = os.path.dirname(__file__)
    ret = os.path.join(dirname, "../../../setup")
    if os.path.isdir(ret):
        return ret
    raise Exception("Unable to find setup directory.")

# Descriptors of naming contexts and other important objects

# "get_schema_descriptor" is located in "schema.py"

def get_sites_descriptor(domain_sid):
    sddl = "O:EAG:EAD:AI(A;;RPLCLORC;;;AU)" \
           "(A;;RPWPCRCCLCLORCWOWDSW;;;EA)" \
           "(A;;RPWPCRCCDCLCLORCWOWDSDDTSW;;;SY)" \
           "(A;CIID;RPWPCRCCDCLCLORCWOWDSDDTSW;;;EA)" \
           "(A;CIID;RPWPCRCCLCLORCWOWDSDSW;;;DA)" \
           "S:AI(AU;CISA;CCDCSDDT;;;WD)" \
           "(OU;CIIOSA;CR;;f0f8ffab-1191-11d0-a060-00aa006c33ed;WD)" \
           "(OU;CIIOSA;WP;f30e3bbe-9ff0-11d1-b603-0000f80367c1;bf967ab3-0de6-11d0-a285-00aa003049e2;WD)" \
           "(OU;CIIOSA;WP;f30e3bbf-9ff0-11d1-b603-0000f80367c1;bf967ab3-0de6-11d0-a285-00aa003049e2;WD)" \
           "(OU;CIIOSA;WP;3e10944c-c354-11d0-aff8-0000f80367c1;b7b13124-b82e-11d0-afee-0000f80367c1;WD)"
    sec = security.descriptor.from_sddl(sddl, domain_sid)
    return ndr_pack(sec)

def get_config_descriptor(domain_sid):
    sddl = "O:EAG:EAD:(OA;;CR;1131f6aa-9c07-11d1-f79f-00c04fc2dcd2;;ED)" \
           "(OA;;CR;1131f6ab-9c07-11d1-f79f-00c04fc2dcd2;;ED)" \
           "(OA;;CR;1131f6ac-9c07-11d1-f79f-00c04fc2dcd2;;ED)" \
           "(OA;;CR;1131f6aa-9c07-11d1-f79f-00c04fc2dcd2;;BA)" \
           "(OA;;CR;1131f6ab-9c07-11d1-f79f-00c04fc2dcd2;;BA)" \
           "(OA;;CR;1131f6ac-9c07-11d1-f79f-00c04fc2dcd2;;BA)" \
           "(A;;RPLCLORC;;;AU)(A;CI;RPWPCRCCDCLCLORCWOWDSDDTSW;;;EA)" \
           "(A;;RPWPCRCCDCLCLORCWOWDSDDTSW;;;SY)(A;CIIO;RPWPCRCCLCLORCWOWDSDSW;;;DA)" \
           "(OA;;CR;1131f6ad-9c07-11d1-f79f-00c04fc2dcd2;;ED)" \
           "(OA;;CR;89e95b76-444d-4c62-991a-0facbeda640c;;ED)" \
           "(OA;;CR;1131f6ad-9c07-11d1-f79f-00c04fc2dcd2;;BA)" \
           "(OA;;CR;89e95b76-444d-4c62-991a-0facbeda640c;;BA)" \
           "(OA;;CR;1131f6aa-9c07-11d1-f79f-00c04fc2dcd2;;ER)" \
           "S:(AU;SA;WPWOWD;;;WD)(AU;SA;CR;;;BA)(AU;SA;CR;;;DU)" \
           "(OU;SA;CR;45ec5156-db7e-47bb-b53f-dbeb2d03c40f;;WD)"
    sec = security.descriptor.from_sddl(sddl, domain_sid)
    return ndr_pack(sec)

def get_domain_descriptor(domain_sid):
    sddl= "O:BAG:BAD:AI(OA;CIIO;RP;4c164200-20c0-11d0-a768-00aa006e0529;4828cc14-1437-45bc-9b07-ad6f015e5f28;RU)" \
        "(OA;CIIO;RP;4c164200-20c0-11d0-a768-00aa006e0529;bf967aba-0de6-11d0-a285-00aa003049e2;RU)" \
    "(OA;CIIO;RP;5f202010-79a5-11d0-9020-00c04fc2d4cf;4828cc14-1437-45bc-9b07-ad6f015e5f28;RU)" \
    "(OA;CIIO;RP;5f202010-79a5-11d0-9020-00c04fc2d4cf;bf967aba-0de6-11d0-a285-00aa003049e2;RU)" \
    "(OA;CIIO;RP;bc0ac240-79a9-11d0-9020-00c04fc2d4cf;4828cc14-1437-45bc-9b07-ad6f015e5f28;RU)" \
    "(OA;CIIO;RP;bc0ac240-79a9-11d0-9020-00c04fc2d4cf;bf967aba-0de6-11d0-a285-00aa003049e2;RU)" \
    "(OA;CIIO;RP;59ba2f42-79a2-11d0-9020-00c04fc2d3cf;4828cc14-1437-45bc-9b07-ad6f015e5f28;RU)" \
    "(OA;CIIO;RP;59ba2f42-79a2-11d0-9020-00c04fc2d3cf;bf967aba-0de6-11d0-a285-00aa003049e2;RU)" \
    "(OA;CIIO;RP;037088f8-0ae1-11d2-b422-00a0c968f939;4828cc14-1437-45bc-9b07-ad6f015e5f28;RU)" \
    "(OA;CIIO;RP;037088f8-0ae1-11d2-b422-00a0c968f939;bf967aba-0de6-11d0-a285-00aa003049e2;RU)" \
    "(OA;;CR;1131f6aa-9c07-11d1-f79f-00c04fc2dcd2;;ER)" \
    "(OA;;CR;1131f6ad-9c07-11d1-f79f-00c04fc2dcd2;;DD)" \
    "(OA;CIIO;RP;b7c69e6d-2cc7-11d2-854e-00a0c983f608;bf967a86-0de6-11d0-a285-00aa003049e2;ED)" \
    "(OA;CIIO;RP;b7c69e6d-2cc7-11d2-854e-00a0c983f608;bf967a9c-0de6-11d0-a285-00aa003049e2;ED)" \
    "(OA;CIIO;RP;b7c69e6d-2cc7-11d2-854e-00a0c983f608;bf967aba-0de6-11d0-a285-00aa003049e2;ED)" \
    "(OA;;CR;89e95b76-444d-4c62-991a-0facbeda640c;;BA)" \
    "(OA;;CR;1131f6aa-9c07-11d1-f79f-00c04fc2dcd2;;BA)" \
    "(OA;;CR;1131f6ab-9c07-11d1-f79f-00c04fc2dcd2;;BA)" \
    "(OA;;CR;1131f6ac-9c07-11d1-f79f-00c04fc2dcd2;;BA)" \
    "(OA;;CR;1131f6ad-9c07-11d1-f79f-00c04fc2dcd2;;BA)" \
    "(OA;;CR;1131f6ae-9c07-11d1-f79f-00c04fc2dcd2;;BA)" \
    "(OA;;CR;e2a36dc9-ae17-47c3-b58b-be34c55ba633;;IF)" \
    "(OA;;RP;c7407360-20bf-11d0-a768-00aa006e0529;;RU)" \
    "(OA;;RP;b8119fd0-04f6-4762-ab7a-4986c76b3f9a;;RU)" \
    "(OA;CIIO;RPLCLORC;;4828cc14-1437-45bc-9b07-ad6f015e5f28;RU)" \
    "(OA;CIIO;RPLCLORC;;bf967a9c-0de6-11d0-a285-00aa003049e2;RU)" \
    "(OA;CIIO;RPLCLORC;;bf967aba-0de6-11d0-a285-00aa003049e2;RU)" \
    "(OA;;CR;05c74c5e-4deb-43b4-bd9f-86664c2a7fd5;;AU)" \
    "(OA;;CR;89e95b76-444d-4c62-991a-0facbeda640c;;ED)" \
    "(OA;;CR;ccc2dc7d-a6ad-4a7a-8846-c04e3cc53501;;AU)" \
    "(OA;;CR;280f369c-67c7-438e-ae98-1d46f3c6f541;;AU)" \
    "(OA;;CR;1131f6aa-9c07-11d1-f79f-00c04fc2dcd2;;ED)" \
    "(OA;;CR;1131f6ab-9c07-11d1-f79f-00c04fc2dcd2;;ED)" \
    "(OA;;CR;1131f6ac-9c07-11d1-f79f-00c04fc2dcd2;;ED)" \
    "(OA;;CR;1131f6ae-9c07-11d1-f79f-00c04fc2dcd2;;ED)" \
    "(OA;;RP;b8119fd0-04f6-4762-ab7a-4986c76b3f9a;;AU)" \
    "(OA;CIIO;RPWPCR;91e647de-d96f-4b70-9557-d63ff4f3ccd8;;PS)" \
    "(A;;RPWPCRCCLCLORCWOWDSW;;;DA)" \
    "(A;CI;RPWPCRCCDCLCLORCWOWDSDDTSW;;;EA)" \
    "(A;;RPRC;;;RU)" \
    "(A;CI;LC;;;RU)" \
    "(A;CI;RPWPCRCCLCLORCWOWDSDSW;;;BA)" \
    "(A;;RP;;;WD)" \
    "(A;;RPLCLORC;;;ED)" \
    "(A;;RPLCLORC;;;AU)" \
    "(A;;RPWPCRCCDCLCLORCWOWDSDDTSW;;;SY)" \
    "S:AI(OU;CISA;WP;f30e3bbe-9ff0-11d1-b603-0000f80367c1;bf967aa5-0de6-11d0-a285-00aa003049e2;WD)" \
    "(OU;CISA;WP;f30e3bbf-9ff0-11d1-b603-0000f80367c1;bf967aa5-0de6-11d0-a285-00aa003049e2;WD)" \
    "(AU;SA;CR;;;DU)(AU;SA;CR;;;BA)(AU;SA;WPWOWD;;;WD)"
    sec = security.descriptor.from_sddl(sddl, domain_sid)
    return ndr_pack(sec)

DEFAULTSITE = "Default-First-Site-Name"
LAST_PROVISION_USN_ATTRIBUTE = "lastProvisionUSN"

class ProvisionPaths(object):

    def __init__(self):
        self.shareconf = None
        self.hklm = None
        self.hkcu = None
        self.hkcr = None
        self.hku = None
        self.hkpd = None
        self.hkpt = None
        self.samdb = None
        self.idmapdb = None
        self.secrets = None
        self.keytab = None
        self.dns_keytab = None
        self.dns = None
        self.winsdb = None
        self.private_dir = None


class ProvisionNames(object):

    def __init__(self):
        self.rootdn = None
        self.domaindn = None
        self.configdn = None
        self.schemadn = None
        self.ldapmanagerdn = None
        self.dnsdomain = None
        self.realm = None
        self.netbiosname = None
        self.domain = None
        self.hostname = None
        self.sitename = None
        self.smbconf = None


def update_provision_usn(samdb, low, high, replace=False):
    """Update the field provisionUSN in sam.ldb

    This field is used to track range of USN modified by provision and 
    upgradeprovision.
    This value is used afterward by next provision to figure out if 
    the field have been modified since last provision.

    :param samdb: An LDB object connect to sam.ldb
    :param low: The lowest USN modified by this upgrade
    :param high: The highest USN modified by this upgrade
    :param replace: A boolean indicating if the range should replace any 
                    existing one or appended (default)
    """

    tab = []
    if not replace:
        entry = samdb.search(expression="(&(dn=@PROVISION)(%s=*))" % \
                                LAST_PROVISION_USN_ATTRIBUTE, base="", 
                                scope=ldb.SCOPE_SUBTREE,
                                attrs=[LAST_PROVISION_USN_ATTRIBUTE, "dn"])
        for e in entry[0][LAST_PROVISION_USN_ATTRIBUTE]:
            tab.append(str(e))

    tab.append("%s-%s" % (low, high))
    delta = ldb.Message()
    delta.dn = ldb.Dn(samdb, "@PROVISION")
    delta[LAST_PROVISION_USN_ATTRIBUTE] = ldb.MessageElement(tab,
                                                    ldb.FLAG_MOD_REPLACE,
                                                    LAST_PROVISION_USN_ATTRIBUTE)
    samdb.modify(delta)


def set_provision_usn(samdb, low, high):
    """Set the field provisionUSN in sam.ldb
    This field is used to track range of USN modified by provision and
    upgradeprovision.
    This value is used afterward by next provision to figure out if
    the field have been modified since last provision.

    :param samdb: An LDB object connect to sam.ldb
    :param low: The lowest USN modified by this upgrade
    :param high: The highest USN modified by this upgrade"""
    tab = []
    tab.append("%s-%s" % (low, high))
    delta = ldb.Message()
    delta.dn = ldb.Dn(samdb, "@PROVISION")
    delta[LAST_PROVISION_USN_ATTRIBUTE] = ldb.MessageElement(tab,
                                                  ldb.FLAG_MOD_ADD,
                                                  LAST_PROVISION_USN_ATTRIBUTE)
    samdb.add(delta)


def get_max_usn(samdb,basedn):
    """ This function return the biggest USN present in the provision

    :param samdb: A LDB object pointing to the sam.ldb
    :param basedn: A string containing the base DN of the provision
                    (ie. DC=foo, DC=bar)
    :return: The biggest USN in the provision"""

    res = samdb.search(expression="objectClass=*",base=basedn,
                         scope=ldb.SCOPE_SUBTREE,attrs=["uSNChanged"],
                         controls=["search_options:1:2",
                                   "server_sort:1:1:uSNChanged",
                                   "paged_results:1:1"])
    return res[0]["uSNChanged"]
    
def get_last_provision_usn(sam):
    """Get the lastest USN modified by a provision or an upgradeprovision

    :param sam: An LDB object pointing to the sam.ldb
    :return an integer corresponding to the highest USN modified by 
            (upgrade)provision, 0 is this value is unknown"""

    entry = sam.search(expression="(&(dn=@PROVISION)(%s=*))" % \
                        LAST_PROVISION_USN_ATTRIBUTE,
                        base="", scope=ldb.SCOPE_SUBTREE,
                        attrs=[LAST_PROVISION_USN_ATTRIBUTE])
    if len(entry):
        range = []
        idx = 0
        p = re.compile(r'-')
        for r in entry[0][LAST_PROVISION_USN_ATTRIBUTE]:
            tab = p.split(str(r))
            range.append(tab[0])
            range.append(tab[1])
            idx = idx + 1
        return range
    else:
        return None

class ProvisionResult(object):

    def __init__(self):
        self.paths = None
        self.domaindn = None
        self.lp = None
        self.samdb = None


def check_install(lp, session_info, credentials):
    """Check whether the current install seems ok.
    
    :param lp: Loadparm context
    :param session_info: Session information
    :param credentials: Credentials
    """
    if lp.get("realm") == "":
        raise Exception("Realm empty")
    samdb = Ldb(lp.get("sam database"), session_info=session_info, 
            credentials=credentials, lp=lp)
    if len(samdb.search("(cn=Administrator)")) != 1:
        raise ProvisioningError("No administrator account found")


def findnss(nssfn, names):
    """Find a user or group from a list of possibilities.
    
    :param nssfn: NSS Function to try (should raise KeyError if not found)
    :param names: Names to check.
    :return: Value return by first names list.
    """
    for name in names:
        try:
            return nssfn(name)
        except KeyError:
            pass
    raise KeyError("Unable to find user/group in %r" % names)


findnss_uid = lambda names: findnss(pwd.getpwnam, names)[2]
findnss_gid = lambda names: findnss(grp.getgrnam, names)[2]


def setup_add_ldif(ldb, ldif_path, subst_vars=None,controls=["relax:0"]):
    """Setup a ldb in the private dir.
    
    :param ldb: LDB file to import data into
    :param ldif_path: Path of the LDIF file to load
    :param subst_vars: Optional variables to subsitute in LDIF.
    :param nocontrols: Optional list of controls, can be None for no controls
    """
    assert isinstance(ldif_path, str)
    data = read_and_sub_file(ldif_path, subst_vars)
    ldb.add_ldif(data, controls)


def setup_modify_ldif(ldb, ldif_path, subst_vars=None,controls=["relax:0"]):
    """Modify a ldb in the private dir.
    
    :param ldb: LDB object.
    :param ldif_path: LDIF file path.
    :param subst_vars: Optional dictionary with substitution variables.
    """
    data = read_and_sub_file(ldif_path, subst_vars)
    ldb.modify_ldif(data, controls)


def setup_ldb(ldb, ldif_path, subst_vars):
    """Import a LDIF a file into a LDB handle, optionally substituting variables.

    :note: Either all LDIF data will be added or none (using transactions).

    :param ldb: LDB file to import into.
    :param ldif_path: Path to the LDIF file.
    :param subst_vars: Dictionary with substitution variables.
    """
    assert ldb is not None
    ldb.transaction_start()
    try:
        setup_add_ldif(ldb, ldif_path, subst_vars)
    except:
        ldb.transaction_cancel()
        raise
    else:
        ldb.transaction_commit()


def provision_paths_from_lp(lp, dnsdomain):
    """Set the default paths for provisioning.

    :param lp: Loadparm context.
    :param dnsdomain: DNS Domain name
    """
    paths = ProvisionPaths()
    paths.private_dir = lp.get("private dir")

    # This is stored without path prefix for the "privateKeytab" attribute in
    # "secrets_dns.ldif".
    paths.dns_keytab = "dns.keytab"
    paths.keytab = "secrets.keytab"

    paths.shareconf = os.path.join(paths.private_dir, "share.ldb")
    paths.samdb = os.path.join(paths.private_dir, lp.get("sam database") or "samdb.ldb")
    paths.idmapdb = os.path.join(paths.private_dir, lp.get("idmap database") or "idmap.ldb")
    paths.secrets = os.path.join(paths.private_dir, lp.get("secrets database") or "secrets.ldb")
    paths.privilege = os.path.join(paths.private_dir, "privilege.ldb")
    paths.dns = os.path.join(paths.private_dir, "dns", dnsdomain + ".zone")
    paths.dns_update_list = os.path.join(paths.private_dir, "dns_update_list")
    paths.spn_update_list = os.path.join(paths.private_dir, "spn_update_list")
    paths.namedconf = os.path.join(paths.private_dir, "named.conf")
    paths.namedconf_update = os.path.join(paths.private_dir, "named.conf.update")
    paths.namedtxt = os.path.join(paths.private_dir, "named.txt")
    paths.krb5conf = os.path.join(paths.private_dir, "krb5.conf")
    paths.winsdb = os.path.join(paths.private_dir, "wins.ldb")
    paths.s4_ldapi_path = os.path.join(paths.private_dir, "ldapi")
    paths.phpldapadminconfig = os.path.join(paths.private_dir, 
                                            "phpldapadmin-config.php")
    paths.hklm = "hklm.ldb"
    paths.hkcr = "hkcr.ldb"
    paths.hkcu = "hkcu.ldb"
    paths.hku = "hku.ldb"
    paths.hkpd = "hkpd.ldb"
    paths.hkpt = "hkpt.ldb"
    paths.sysvol = lp.get("path", "sysvol")
    paths.netlogon = lp.get("path", "netlogon")
    paths.smbconf = lp.configfile
    return paths


def guess_names(lp=None, hostname=None, domain=None, dnsdomain=None,
                serverrole=None, rootdn=None, domaindn=None, configdn=None,
                schemadn=None, serverdn=None, sitename=None):
    """Guess configuration settings to use."""

    if hostname is None:
        hostname = socket.gethostname().split(".")[0]

    netbiosname = lp.get("netbios name")
    if netbiosname is None:
        netbiosname = hostname
    assert netbiosname is not None
    netbiosname = netbiosname.upper()
    if not valid_netbios_name(netbiosname):
        raise InvalidNetbiosName(netbiosname)

    if dnsdomain is None:
        dnsdomain = lp.get("realm")
        if dnsdomain is None or dnsdomain == "":
            raise ProvisioningError("guess_names: 'realm' not specified in supplied %s!", lp.configfile)

    dnsdomain = dnsdomain.lower()

    if serverrole is None:
        serverrole = lp.get("server role")
        if serverrole is None:
            raise ProvisioningError("guess_names: 'server role' not specified in supplied %s!" % lp.configfile)

    serverrole = serverrole.lower()

    realm = dnsdomain.upper()

    if lp.get("realm") == "":
        raise ProvisioningError("guess_names: 'realm =' was not specified in supplied %s.  Please remove the smb.conf file and let provision generate it" % lp.configfile)

    if lp.get("realm").upper() != realm:
        raise ProvisioningError("guess_names: 'realm=%s' in %s must match chosen realm '%s'!  Please remove the smb.conf file and let provision generate it" % (lp.get("realm").upper(), realm, lp.configfile))

    if lp.get("server role").lower() != serverrole:
        raise ProvisioningError("guess_names: 'server role=%s' in %s must match chosen server role '%s'!  Please remove the smb.conf file and let provision generate it" % (lp.get("server role").upper(), serverrole, lp.configfile))

    if serverrole == "domain controller":
        if domain is None:
            # This will, for better or worse, default to 'WORKGROUP'
            domain = lp.get("workgroup")
        domain = domain.upper()

        if lp.get("workgroup").upper() != domain:
            raise ProvisioningError("guess_names: Workgroup '%s' in smb.conf must match chosen domain '%s'!  Please remove the %s file and let provision generate it" % (lp.get("workgroup").upper(), domain, lp.configfile))

        if domaindn is None:
            domaindn = "DC=" + dnsdomain.replace(".", ",DC=")
    else:
        domain = netbiosname
        if domaindn is None:
            domaindn = "DC=" + netbiosname
        
    if not valid_netbios_name(domain):
        raise InvalidNetbiosName(domain)
        
    if hostname.upper() == realm:
        raise ProvisioningError("guess_names: Realm '%s' must not be equal to hostname '%s'!" % (realm, hostname))
    if netbiosname == realm:
        raise ProvisioningError("guess_names: Realm '%s' must not be equal to netbios hostname '%s'!" % (realm, netbiosname))
    if domain == realm:
        raise ProvisioningError("guess_names: Realm '%s' must not be equal to short domain name '%s'!" % (realm, domain))

    if rootdn is None:
       rootdn = domaindn
       
    if configdn is None:
        configdn = "CN=Configuration," + rootdn
    if schemadn is None:
        schemadn = "CN=Schema," + configdn

    if sitename is None:
        sitename=DEFAULTSITE

    names = ProvisionNames()
    names.rootdn = rootdn
    names.domaindn = domaindn
    names.configdn = configdn
    names.schemadn = schemadn
    names.ldapmanagerdn = "CN=Manager," + rootdn
    names.dnsdomain = dnsdomain
    names.domain = domain
    names.realm = realm
    names.netbiosname = netbiosname
    names.hostname = hostname
    names.sitename = sitename
    names.serverdn = "CN=%s,CN=Servers,CN=%s,CN=Sites,%s" % (netbiosname, sitename, configdn)
 
    return names
    

def make_smbconf(smbconf, setup_path, hostname, domain, realm, serverrole, 
                 targetdir, sid_generator="internal", eadb=False):
    """Create a new smb.conf file based on a couple of basic settings.
    """
    assert smbconf is not None
    if hostname is None:
        hostname = socket.gethostname().split(".")[0]
    netbiosname = hostname.upper()

    if serverrole is None:
        serverrole = "standalone"

    assert serverrole in ("domain controller", "member server", "standalone")
    if serverrole == "domain controller":
        smbconfsuffix = "dc"
    elif serverrole == "member server":
        smbconfsuffix = "member"
    elif serverrole == "standalone":
        smbconfsuffix = "standalone"

    if sid_generator is None:
        sid_generator = "internal"

    assert domain is not None
    domain = domain.upper()

    assert realm is not None
    realm = realm.upper()

    default_lp = samba.param.LoadParm()
    #Load non-existant file
    if os.path.exists(smbconf):
        default_lp.load(smbconf)
    if eadb:
        if targetdir is not None:
            privdir = os.path.join(targetdir, "private")
        else:
            privdir = default_lp.get("private dir")
        posixeadb_line = "posix:eadb = " + os.path.abspath(os.path.join(privdir, "eadb.tdb"))
    else:
        posixeadb_line = ""

    if targetdir is not None:
        privatedir_line = "private dir = " + os.path.abspath(os.path.join(targetdir, "private"))
        lockdir_line = "lock dir = " + os.path.abspath(targetdir)

        default_lp.set("lock dir", os.path.abspath(targetdir))
    else:
        privatedir_line = ""
        lockdir_line = ""

    if sid_generator == "internal":
        sid_generator_line = ""
    else:
        sid_generator_line = "sid generator = " + sid_generator

    used_setup_dir = setup_path("")
    default_setup_dir = default_lp.get("setup directory")
    setupdir_line = ""
    if used_setup_dir != default_setup_dir:
        setupdir_line = "setup directory = %s" % used_setup_dir
        default_lp.set("setup directory", used_setup_dir)

    sysvol = os.path.join(default_lp.get("lock dir"), "sysvol")
    netlogon = os.path.join(sysvol, realm.lower(), "scripts")

    setup_file(setup_path("provision.smb.conf.%s" % smbconfsuffix), 
               smbconf, {
            "NETBIOS_NAME": netbiosname,
            "DOMAIN": domain,
            "REALM": realm,
            "SERVERROLE": serverrole,
            "NETLOGONPATH": netlogon,
            "SYSVOLPATH": sysvol,
            "SETUPDIRECTORY_LINE": setupdir_line,
            "SIDGENERATOR_LINE": sid_generator_line,
            "PRIVATEDIR_LINE": privatedir_line,
            "LOCKDIR_LINE": lockdir_line,
            "POSIXEADB_LINE": posixeadb_line
            })


def setup_name_mappings(samdb, idmap, sid, domaindn, root_uid, nobody_uid,
                        users_gid, wheel_gid):
    """setup reasonable name mappings for sam names to unix names.

    :param samdb: SamDB object.
    :param idmap: IDmap db object.
    :param sid: The domain sid.
    :param domaindn: The domain DN.
    :param root_uid: uid of the UNIX root user.
    :param nobody_uid: uid of the UNIX nobody user.
    :param users_gid: gid of the UNIX users group.
    :param wheel_gid: gid of the UNIX wheel group."""
    idmap.setup_name_mapping("S-1-5-7", idmap.TYPE_UID, nobody_uid)
    idmap.setup_name_mapping("S-1-5-32-544", idmap.TYPE_GID, wheel_gid)
    
    idmap.setup_name_mapping(sid + "-500", idmap.TYPE_UID, root_uid)
    idmap.setup_name_mapping(sid + "-513", idmap.TYPE_GID, users_gid)


def setup_samdb_partitions(samdb_path, setup_path, logger, lp, session_info, 
                           provision_backend, names, schema, serverrole, 
                           erase=False):
    """Setup the partitions for the SAM database. 
    
    Alternatively, provision() may call this, and then populate the database.
    
    :note: This will wipe the Sam Database!
    
    :note: This function always removes the local SAM LDB file. The erase 
        parameter controls whether to erase the existing data, which 
        may not be stored locally but in LDAP.

    """
    assert session_info is not None

    # We use options=["modules:"] to stop the modules loading - we
    # just want to wipe and re-initialise the database, not start it up

    try:
        os.unlink(samdb_path)
    except OSError:
        pass

    samdb = Ldb(url=samdb_path, session_info=session_info, 
                lp=lp, options=["modules:"])

    ldap_backend_line = "# No LDAP backend"
    if provision_backend.type is not "ldb":
        ldap_backend_line = "ldapBackend: %s" % provision_backend.ldap_uri

    samdb.transaction_start()
    try:
        logger.info("Setting up sam.ldb partitions and settings")
        setup_add_ldif(samdb, setup_path("provision_partitions.ldif"), {
                "SCHEMADN": ldb.Dn(schema.ldb, names.schemadn).get_casefold(), 
                "CONFIGDN": ldb.Dn(schema.ldb, names.configdn).get_casefold(),
                "DOMAINDN": ldb.Dn(schema.ldb, names.domaindn).get_casefold(),
                "LDAP_BACKEND_LINE": ldap_backend_line,
        })

        
        setup_add_ldif(samdb, setup_path("provision_init.ldif"), {
                "BACKEND_TYPE": provision_backend.type,
                "SERVER_ROLE": serverrole
                })

        logger.info("Setting up sam.ldb rootDSE")
        setup_samdb_rootdse(samdb, setup_path, names)
    except:
        samdb.transaction_cancel()
        raise
    else:
        samdb.transaction_commit()

        
def secretsdb_self_join(secretsdb, domain, 
                        netbiosname, machinepass, domainsid=None,
                        realm=None, dnsdomain=None,
                        keytab_path=None, 
                        key_version_number=1,
                        secure_channel_type=SEC_CHAN_WKSTA):
    """Add domain join-specific bits to a secrets database.
    
    :param secretsdb: Ldb Handle to the secrets database
    :param machinepass: Machine password
    """
    attrs=["whenChanged",
           "secret",
           "priorSecret",
           "priorChanged",
           "krb5Keytab",
           "privateKeytab"]

    if realm is not None:
      if dnsdomain is None:
          dnsdomain = realm.lower()
      dnsname = '%s.%s' % (netbiosname.lower(), dnsdomain.lower())
    else:
      dnsname = None
    shortname = netbiosname.lower()
    
    #We don't need to set msg["flatname"] here, because rdn_name will handle it, and it causes problems for modifies anyway
    msg = ldb.Message(ldb.Dn(secretsdb, "flatname=%s,cn=Primary Domains" % domain))
    msg["secureChannelType"] = [str(secure_channel_type)]
    msg["objectClass"] = ["top", "primaryDomain"]
    if dnsname is not None:
      msg["objectClass"] = ["top", "primaryDomain", "kerberosSecret"]
      msg["realm"] = [realm]
      msg["saltPrincipal"] = ["host/%s@%s" % (dnsname, realm.upper())]
      msg["msDS-KeyVersionNumber"] = [str(key_version_number)]
      msg["privateKeytab"] = ["secrets.keytab"]

    msg["secret"] = [machinepass]
    msg["samAccountName"] = ["%s$" % netbiosname]
    msg["secureChannelType"] = [str(secure_channel_type)]
    if domainsid is not None:
        msg["objectSid"] = [ndr_pack(domainsid)]
    
    # This complex expression tries to ensure that we don't have more
    # than one record for this SID, realm or netbios domain at a time,
    # but we don't delete the old record that we are about to modify,
    # because that would delete the keytab and previous password.
    res = secretsdb.search(base="cn=Primary Domains", 
                           attrs=attrs, 
                           expression=("(&(|(flatname=%s)(realm=%s)(objectSid=%s))(objectclass=primaryDomain)(!(dn=%s)))" % (domain, realm, str(domainsid), str(msg.dn))),
                           scope=ldb.SCOPE_ONELEVEL)
    
    for del_msg in res:
        secretsdb.delete(del_msg.dn)

    res = secretsdb.search(base=msg.dn, attrs=attrs, scope=ldb.SCOPE_BASE)

    if len(res) == 1:
      msg["priorSecret"] = [res[0]["secret"][0]]
      msg["priorWhenChanged"] = [res[0]["whenChanged"][0]]

      try:
        msg["privateKeytab"] = [res[0]["privateKeytab"][0]]
      except KeyError:
        pass

      try:
        msg["krb5Keytab"] = [res[0]["krb5Keytab"][0]]
      except KeyError:
        pass

      for el in msg:
          if el != 'dn':
              msg[el].set_flags(ldb.FLAG_MOD_REPLACE)
      secretsdb.modify(msg)
      secretsdb.rename(res[0].dn, msg.dn)
    else:
      spn = [ 'HOST/%s' % shortname ]
      if secure_channel_type == SEC_CHAN_BDC and dnsname is not None:
          # we are a domain controller then we add servicePrincipalName entries
          # for the keytab code to update
          spn.extend([ 'HOST/%s' % dnsname ])
      msg["servicePrincipalName"] = spn

      secretsdb.add(msg)


def secretsdb_setup_dns(secretsdb, setup_path, names, private_dir,
                        realm, dnsdomain,
                        dns_keytab_path, dnspass):
    """Add DNS specific bits to a secrets database.
    
    :param secretsdb: Ldb Handle to the secrets database
    :param setup_path: Setup path function
    :param machinepass: Machine password
    """
    try:
        os.unlink(os.path.join(private_dir, dns_keytab_path))
    except OSError:
        pass

    setup_ldb(secretsdb, setup_path("secrets_dns.ldif"), { 
            "REALM": realm,
            "DNSDOMAIN": dnsdomain,
            "DNS_KEYTAB": dns_keytab_path,
            "DNSPASS_B64": b64encode(dnspass),
            "HOSTNAME": names.hostname,
            "DNSNAME" : '%s.%s' % (names.netbiosname.lower(), names.dnsdomain.lower())
            })


def setup_secretsdb(paths, setup_path, session_info, backend_credentials, lp):
    """Setup the secrets database.

   :note: This function does not handle exceptions and transaction on purpose,
   it's up to the caller to do this job.

    :param path: Path to the secrets database.
    :param setup_path: Get the path to a setup file.
    :param session_info: Session info.
    :param credentials: Credentials
    :param lp: Loadparm context
    :return: LDB handle for the created secrets database
    """
    if os.path.exists(paths.secrets):
        os.unlink(paths.secrets)

    keytab_path = os.path.join(paths.private_dir, paths.keytab)
    if os.path.exists(keytab_path):
        os.unlink(keytab_path)

    dns_keytab_path = os.path.join(paths.private_dir, paths.dns_keytab)
    if os.path.exists(dns_keytab_path):
        os.unlink(dns_keytab_path)

    path = paths.secrets

    secrets_ldb = Ldb(path, session_info=session_info, 
                      lp=lp)
    secrets_ldb.erase()
    secrets_ldb.load_ldif_file_add(setup_path("secrets_init.ldif"))
    secrets_ldb = Ldb(path, session_info=session_info, 
                      lp=lp)
    secrets_ldb.transaction_start()
    try:
        secrets_ldb.load_ldif_file_add(setup_path("secrets.ldif"))

        if backend_credentials is not None and backend_credentials.authentication_requested():
            if backend_credentials.get_bind_dn() is not None:
                setup_add_ldif(secrets_ldb, setup_path("secrets_simple_ldap.ldif"), {
                        "LDAPMANAGERDN": backend_credentials.get_bind_dn(),
                        "LDAPMANAGERPASS_B64": b64encode(backend_credentials.get_password())
                        })
            else:
                setup_add_ldif(secrets_ldb, setup_path("secrets_sasl_ldap.ldif"), {
                        "LDAPADMINUSER": backend_credentials.get_username(),
                        "LDAPADMINREALM": backend_credentials.get_realm(),
                        "LDAPADMINPASS_B64": b64encode(backend_credentials.get_password())
                        })

        return secrets_ldb
    except:
        secrets_ldb.transaction_cancel()
        raise

def setup_privileges(path, setup_path, session_info, lp):
    """Setup the privileges database.

    :param path: Path to the privileges database.
    :param setup_path: Get the path to a setup file.
    :param session_info: Session info.
    :param credentials: Credentials
    :param lp: Loadparm context
    :return: LDB handle for the created secrets database
    """
    if os.path.exists(path):
        os.unlink(path)
    privilege_ldb = Ldb(path, session_info=session_info, lp=lp)
    privilege_ldb.erase()
    privilege_ldb.load_ldif_file_add(setup_path("provision_privilege.ldif"))


def setup_registry(path, setup_path, session_info, lp):
    """Setup the registry.
    
    :param path: Path to the registry database
    :param setup_path: Function that returns the path to a setup.
    :param session_info: Session information
    :param credentials: Credentials
    :param lp: Loadparm context
    """
    reg = samba.registry.Registry()
    hive = samba.registry.open_ldb(path, session_info=session_info, 
                         lp_ctx=lp)
    reg.mount_hive(hive, samba.registry.HKEY_LOCAL_MACHINE)
    provision_reg = setup_path("provision.reg")
    assert os.path.exists(provision_reg)
    reg.diff_apply(provision_reg)


def setup_idmapdb(path, setup_path, session_info, lp):
    """Setup the idmap database.

    :param path: path to the idmap database
    :param setup_path: Function that returns a path to a setup file
    :param session_info: Session information
    :param credentials: Credentials
    :param lp: Loadparm context
    """
    if os.path.exists(path):
        os.unlink(path)

    idmap_ldb = IDmapDB(path, session_info=session_info,
                        lp=lp)

    idmap_ldb.erase()
    idmap_ldb.load_ldif_file_add(setup_path("idmap_init.ldif"))
    return idmap_ldb


def setup_samdb_rootdse(samdb, setup_path, names):
    """Setup the SamDB rootdse.

    :param samdb: Sam Database handle
    :param setup_path: Obtain setup path
    """
    setup_add_ldif(samdb, setup_path("provision_rootdse_add.ldif"), {
        "SCHEMADN": names.schemadn, 
        "DOMAINDN": names.domaindn,
        "ROOTDN": names.rootdn,
        "CONFIGDN": names.configdn,
        "SERVERDN": names.serverdn,
        })
        

def setup_self_join(samdb, names,
                    machinepass, dnspass, 
                    domainsid, next_rid, invocationid, setup_path,
                    policyguid, policyguid_dc, domainControllerFunctionality,
                    ntdsguid):
    """Join a host to its own domain."""
    assert isinstance(invocationid, str)
    if ntdsguid is not None:
        ntdsguid_line = "objectGUID: %s\n"%ntdsguid
    else:
        ntdsguid_line = ""
    setup_add_ldif(samdb, setup_path("provision_self_join.ldif"), { 
              "CONFIGDN": names.configdn, 
              "SCHEMADN": names.schemadn,
              "DOMAINDN": names.domaindn,
              "SERVERDN": names.serverdn,
              "INVOCATIONID": invocationid,
              "NETBIOSNAME": names.netbiosname,
              "DEFAULTSITE": names.sitename,
              "DNSNAME": "%s.%s" % (names.hostname, names.dnsdomain),
              "MACHINEPASS_B64": b64encode(machinepass),
              "REALM": names.realm,
              "DOMAIN": names.domain,
              "DOMAINSID": str(domainsid),
              "DCRID": str(next_rid),
              "DNSDOMAIN": names.dnsdomain,
              "SAMBA_VERSION_STRING": version,
              "NTDSGUID": ntdsguid_line,
              "DOMAIN_CONTROLLER_FUNCTIONALITY": str(domainControllerFunctionality)})

    setup_add_ldif(samdb, setup_path("provision_group_policy.ldif"), { 
              "POLICYGUID": policyguid,
              "POLICYGUID_DC": policyguid_dc,
              "DNSDOMAIN": names.dnsdomain,
              "DOMAINSID": str(domainsid),
              "DOMAINDN": names.domaindn})
    
    # add the NTDSGUID based SPNs
    ntds_dn = "CN=NTDS Settings,%s" % names.serverdn
    names.ntdsguid = samdb.searchone(basedn=ntds_dn, attribute="objectGUID",
                                     expression="", scope=ldb.SCOPE_BASE)
    assert isinstance(names.ntdsguid, str)

    # Setup fSMORoleOwner entries to point at the newly created DC entry
    setup_modify_ldif(samdb, setup_path("provision_self_join_modify.ldif"), {
              "DOMAIN": names.domain,
              "DNSDOMAIN": names.dnsdomain,
              "DOMAINDN": names.domaindn,
              "CONFIGDN": names.configdn,
              "SCHEMADN": names.schemadn, 
              "DEFAULTSITE": names.sitename,
              "SERVERDN": names.serverdn,
              "NETBIOSNAME": names.netbiosname,
              "NTDSGUID": names.ntdsguid,
              "RIDALLOCATIONSTART": str(next_rid + 100),
              "RIDALLOCATIONEND": str(next_rid + 100 + 499),
              })

    # This is partially Samba4 specific and should be replaced by the correct
    # DNS AD-style setup
    setup_add_ldif(samdb, setup_path("provision_dns_add.ldif"), {
              "DNSDOMAIN": names.dnsdomain,
              "DOMAINDN": names.domaindn,
              "DNSPASS_B64": b64encode(dnspass),
              "HOSTNAME" : names.hostname,
              "DNSNAME" : '%s.%s' % (names.netbiosname.lower(), names.dnsdomain.lower())
              })

def getpolicypath(sysvolpath, dnsdomain, guid):
    """Return the physical path of policy given its guid.

    :param sysvolpath: Path to the sysvol folder
    :param dnsdomain: DNS name of the AD domain
    :param guid: The GUID of the policy
    :return: A string with the complete path to the policy folder
    """

    if guid[0] != "{":
        guid = "{%s}" % guid
    policy_path = os.path.join(sysvolpath, dnsdomain, "Policies", guid)
    return policy_path

def create_gpo_struct(policy_path):
    if not os.path.exists(policy_path):
        os.makedirs(policy_path, 0775)
    open(os.path.join(policy_path, "GPT.INI"), 'w').write(
                      "[General]\r\nVersion=0")
    p = os.path.join(policy_path, "MACHINE")
    if not os.path.exists(p):
        os.makedirs(p, 0775)
    p = os.path.join(policy_path, "USER")
    if not os.path.exists(p):
        os.makedirs(p, 0775)


def create_default_gpo(sysvolpath, dnsdomain, policyguid, policyguid_dc):
    """Create the default GPO for a domain

        :param sysvolpath: Physical path for the sysvol folder
        :param dnsdomain: DNS domain name of the AD domain
        :param policyguid: GUID of the default domain policy
        :param policyguid_dc: GUID of the default domain controler policy
    """

    policy_path = getpolicypath(sysvolpath,dnsdomain,policyguid)
    create_gpo_struct(policy_path)

    policy_path = getpolicypath(sysvolpath,dnsdomain,policyguid_dc)
    create_gpo_struct(policy_path)


def setup_samdb(path, setup_path, session_info, provision_backend, lp, names,
        logger, domainsid, domainguid, policyguid, policyguid_dc, fill,
        adminpass, krbtgtpass, machinepass, invocationid, dnspass, ntdsguid,
        serverrole, am_rodc=False, dom_for_fun_level=None, schema=None,
        next_rid=1000):
    """Setup a complete SAM Database.
    
    :note: This will wipe the main SAM database file!
    """


    # Provision does not make much sense values larger than 1000000000
    # as the upper range of the rIDAvailablePool is 1073741823 and
    # we don't want to create a domain that cannot allocate rids.
    if next_rid < 1000 or next_rid > 1000000000:
        error = "You want to run SAMBA 4 with a next_rid of %u, " % (next_rid)
        error += "the valid range is %u-%u. The default is %u." % (1000, 1000000000, 1000)
        raise ProvisioningError(error)

    # ATTENTION: Do NOT change these default values without discussion with the
    # team and/or release manager. They have a big impact on the whole program!
    domainControllerFunctionality = DS_DOMAIN_FUNCTION_2008_R2

    if dom_for_fun_level is None:
        dom_for_fun_level = DS_DOMAIN_FUNCTION_2003

    if dom_for_fun_level > domainControllerFunctionality:
        raise ProvisioningError("You want to run SAMBA 4 on a domain and forest function level which itself is higher than its actual DC function level (2008_R2). This won't work!")

    domainFunctionality = dom_for_fun_level
    forestFunctionality = dom_for_fun_level

    # Also wipes the database
    setup_samdb_partitions(path, setup_path, logger=logger, lp=lp,
        provision_backend=provision_backend, session_info=session_info,
        names=names, serverrole=serverrole, schema=schema)

    if schema is None:
        schema = Schema(setup_path, domainsid, schemadn=names.schemadn)

    # Load the database, but don's load the global schema and don't connect quite yet
    samdb = SamDB(session_info=session_info, url=None, auto_connect=False,
                  credentials=provision_backend.credentials, lp=lp, global_schema=False,
                  am_rodc=am_rodc)

    logger.info("Pre-loading the Samba 4 and AD schema")

    # Load the schema from the one we computed earlier
    samdb.set_schema(schema)

    # Set the NTDS settings DN manually - in order to have it already around
    # before the provisioned tree exists and we connect
    samdb.set_ntds_settings_dn("CN=NTDS Settings,%s" % names.serverdn)

    # And now we can connect to the DB - the schema won't be loaded from the DB
    samdb.connect(path)

    if fill == FILL_DRS:
        return samdb
        
    samdb.transaction_start()
    try:
        # Set the domain functionality levels onto the database.
        # Various module (the password_hash module in particular) need
        # to know what level of AD we are emulating.

        # These will be fixed into the database via the database
        # modifictions below, but we need them set from the start.
        samdb.set_opaque_integer("domainFunctionality", domainFunctionality)
        samdb.set_opaque_integer("forestFunctionality", forestFunctionality)
        samdb.set_opaque_integer("domainControllerFunctionality", domainControllerFunctionality)

        samdb.set_domain_sid(str(domainsid))
        samdb.set_invocation_id(invocationid)

        logger.info("Adding DomainDN: %s" % names.domaindn)

#impersonate domain admin
        admin_session_info = admin_session(lp, str(domainsid))
        samdb.set_session_info(admin_session_info)
        if domainguid is not None:
            domainguid_line = "objectGUID: %s\n-" % domainguid
        else:
            domainguid_line = ""

        descr = b64encode(get_domain_descriptor(domainsid))
        setup_add_ldif(samdb, setup_path("provision_basedn.ldif"), {
                "DOMAINDN": names.domaindn,
                "DOMAINGUID": domainguid_line,
                "DESCRIPTOR": descr
                })


        setup_modify_ldif(samdb, setup_path("provision_basedn_modify.ldif"), {
            "CREATTIME": str(int(time.time() * 1e7)), # seconds -> ticks
            "DOMAINSID": str(domainsid),
            "NEXTRID": str(next_rid),
            "SCHEMADN": names.schemadn, 
            "NETBIOSNAME": names.netbiosname,
            "DEFAULTSITE": names.sitename,
            "CONFIGDN": names.configdn,
            "SERVERDN": names.serverdn,
            "POLICYGUID": policyguid,
            "DOMAINDN": names.domaindn,
            "DOMAIN_FUNCTIONALITY": str(domainFunctionality),
            "SAMBA_VERSION_STRING": version
            })

        logger.info("Adding configuration container")
        descr = b64encode(get_config_descriptor(domainsid))
        setup_add_ldif(samdb, setup_path("provision_configuration_basedn.ldif"), {
            "CONFIGDN": names.configdn, 
            "DESCRIPTOR": descr,
            })

        # The LDIF here was created when the Schema object was constructed
        logger.info("Setting up sam.ldb schema")
        samdb.add_ldif(schema.schema_dn_add, controls=["relax:0"])
        samdb.modify_ldif(schema.schema_dn_modify)
        samdb.write_prefixes_from_schema()
        samdb.add_ldif(schema.schema_data, controls=["relax:0"])
        setup_add_ldif(samdb, setup_path("aggregate_schema.ldif"), 
                       {"SCHEMADN": names.schemadn})

        logger.info("Reopening sam.ldb with new schema")
    except:
        samdb.transaction_cancel()
        raise
    else:
        samdb.transaction_commit()

    samdb = SamDB(session_info=admin_session_info, auto_connect=False,
                credentials=provision_backend.credentials, lp=lp,
                global_schema=False, am_rodc=am_rodc)

    # Set the NTDS settings DN manually - in order to have it already around
    # before the provisioned tree exists and we connect
    samdb.set_ntds_settings_dn("CN=NTDS Settings,%s" % names.serverdn)

    samdb.connect(path)

    samdb.transaction_start()
    try:
        samdb.invocation_id = invocationid

        logger.info("Setting up sam.ldb configuration data")
        descr = b64encode(get_sites_descriptor(domainsid))
        setup_add_ldif(samdb, setup_path("provision_configuration.ldif"), {
            "CONFIGDN": names.configdn,
            "NETBIOSNAME": names.netbiosname,
            "DEFAULTSITE": names.sitename,
            "DNSDOMAIN": names.dnsdomain,
            "DOMAIN": names.domain,
            "SCHEMADN": names.schemadn,
            "DOMAINDN": names.domaindn,
            "SERVERDN": names.serverdn,
            "FOREST_FUNCTIONALITY": str(forestFunctionality),
            "DOMAIN_FUNCTIONALITY": str(domainFunctionality),
            "SITES_DESCRIPTOR": descr
            })

        logger.info("Setting up display specifiers")
        display_specifiers_ldif = read_ms_ldif(setup_path('display-specifiers/DisplaySpecifiers-Win2k8R2.txt'))
        display_specifiers_ldif = substitute_var(display_specifiers_ldif, {"CONFIGDN": names.configdn})
        check_all_substituted(display_specifiers_ldif)
        samdb.add_ldif(display_specifiers_ldif)

        logger.info("Adding users container")
        setup_add_ldif(samdb, setup_path("provision_users_add.ldif"), {
                "DOMAINDN": names.domaindn})
        logger.info("Modifying users container")
        setup_modify_ldif(samdb, setup_path("provision_users_modify.ldif"), {
                "DOMAINDN": names.domaindn})
        logger.info("Adding computers container")
        setup_add_ldif(samdb, setup_path("provision_computers_add.ldif"), {
                "DOMAINDN": names.domaindn})
        logger.info("Modifying computers container")
        setup_modify_ldif(samdb, setup_path("provision_computers_modify.ldif"), {
                "DOMAINDN": names.domaindn})
        logger.info("Setting up sam.ldb data")
        setup_add_ldif(samdb, setup_path("provision.ldif"), {
            "CREATTIME": str(int(time.time() * 1e7)), # seconds -> ticks
            "DOMAINDN": names.domaindn,
            "NETBIOSNAME": names.netbiosname,
            "DEFAULTSITE": names.sitename,
            "CONFIGDN": names.configdn,
            "SERVERDN": names.serverdn,
            "RIDAVAILABLESTART": str(next_rid + 600),
            "POLICYGUID_DC": policyguid_dc
            })

        setup_modify_ldif(samdb, setup_path("provision_basedn_references.ldif"), {
                "DOMAINDN": names.domaindn})

        setup_modify_ldif(samdb, setup_path("provision_configuration_references.ldif"), {
                "CONFIGDN": names.configdn,
                "SCHEMADN": names.schemadn})
        if fill == FILL_FULL:
            logger.info("Setting up sam.ldb users and groups")
            setup_add_ldif(samdb, setup_path("provision_users.ldif"), {
                "DOMAINDN": names.domaindn,
                "DOMAINSID": str(domainsid),
                "CONFIGDN": names.configdn,
                "ADMINPASS_B64": b64encode(adminpass),
                "KRBTGTPASS_B64": b64encode(krbtgtpass),
                })

            logger.info("Setting up self join")
            setup_self_join(samdb, names=names, invocationid=invocationid,
                            dnspass=dnspass,
                            machinepass=machinepass,
                            domainsid=domainsid,
                            next_rid=next_rid,
                            policyguid=policyguid,
                            policyguid_dc=policyguid_dc,
                            setup_path=setup_path,
                            domainControllerFunctionality=domainControllerFunctionality,
                            ntdsguid=ntdsguid)

            ntds_dn = "CN=NTDS Settings,%s" % names.serverdn
            names.ntdsguid = samdb.searchone(basedn=ntds_dn,
                attribute="objectGUID", expression="", scope=ldb.SCOPE_BASE)
            assert isinstance(names.ntdsguid, str)
    except:
        samdb.transaction_cancel()
        raise
    else:
        samdb.transaction_commit()
        return samdb


FILL_FULL = "FULL"
FILL_NT4SYNC = "NT4SYNC"
FILL_DRS = "DRS"
SYSVOL_ACL = "O:LAG:BAD:P(A;OICI;0x001f01ff;;;BA)(A;OICI;0x001200a9;;;SO)(A;OICI;0x001f01ff;;;SY)(A;OICI;0x001200a9;;;AU)"
POLICIES_ACL = "O:LAG:BAD:P(A;OICI;0x001f01ff;;;BA)(A;OICI;0x001200a9;;;SO)(A;OICI;0x001f01ff;;;SY)(A;OICI;0x001200a9;;;AU)(A;OICI;0x001301bf;;;PA)"

def set_dir_acl(path, acl, lp, domsid):
    setntacl(lp, path, acl, domsid)
    for root, dirs, files in os.walk(path, topdown=False):
        for name in files:
            setntacl(lp, os.path.join(root, name), acl, domsid)
        for name in dirs:
            setntacl(lp, os.path.join(root, name), acl, domsid)


def set_gpos_acl(sysvol, dnsdomain, domainsid, domaindn, samdb, lp):
    """Set ACL on the sysvol/<dnsname>/Policies folder and the policy
    folders beneath.

    :param sysvol: Physical path for the sysvol folder
    :param dnsdomain: The DNS name of the domain
    :param domainsid: The SID of the domain
    :param domaindn: The DN of the domain (ie. DC=...)
    :param samdb: An LDB object on the SAM db
    :param lp: an LP object
    """

    # Set ACL for GPO root folder
    root_policy_path = os.path.join(sysvol, dnsdomain, "Policies")
    setntacl(lp, root_policy_path, POLICIES_ACL, str(domainsid))

    res = samdb.search(base="CN=Policies,CN=System,%s"%(domaindn),
                        attrs=["cn", "nTSecurityDescriptor"],
                        expression="", scope=ldb.SCOPE_ONELEVEL)

    for policy in res:
        acl = ndr_unpack(security.descriptor, 
                         str(policy["nTSecurityDescriptor"])).as_sddl()
        policy_path = getpolicypath(sysvol, dnsdomain, str(policy["cn"]))
        set_dir_acl(policy_path, dsacl2fsacl(acl, str(domainsid)), lp, 
                    str(domainsid))

def setsysvolacl(samdb, netlogon, sysvol, gid, domainsid, dnsdomain, domaindn,
    lp):
    """Set the ACL for the sysvol share and the subfolders

    :param samdb: An LDB object on the SAM db
    :param netlogon: Physical path for the netlogon folder
    :param sysvol: Physical path for the sysvol folder
    :param gid: The GID of the "Domain adminstrators" group
    :param domainsid: The SID of the domain
    :param dnsdomain: The DNS name of the domain
    :param domaindn: The DN of the domain (ie. DC=...)
    """

    try:
        os.chown(sysvol,-1,gid)
    except:
        canchown = False
    else:
        canchown = True

    # Set the SYSVOL_ACL on the sysvol folder and subfolder (first level)
    setntacl(lp,sysvol, SYSVOL_ACL, str(domainsid))
    for root, dirs, files in os.walk(sysvol, topdown=False):
        for name in files:
            if canchown:
                os.chown(os.path.join(root, name), -1, gid)
            setntacl(lp, os.path.join(root, name), SYSVOL_ACL, str(domainsid))
        for name in dirs:
            if canchown:
                os.chown(os.path.join(root, name), -1, gid)
            setntacl(lp, os.path.join(root, name), SYSVOL_ACL, str(domainsid))

    # Set acls on Policy folder and policies folders
    set_gpos_acl(sysvol, dnsdomain, domainsid, domaindn, samdb, lp)


def provision(setup_dir, logger, session_info, 
              credentials, smbconf=None, targetdir=None, samdb_fill=FILL_FULL,
              realm=None, 
              rootdn=None, domaindn=None, schemadn=None, configdn=None, 
              serverdn=None,
              domain=None, hostname=None, hostip=None, hostip6=None, 
              domainsid=None, next_rid=1000,
              adminpass=None, ldapadminpass=None,
              krbtgtpass=None, domainguid=None, 
              policyguid=None, policyguid_dc=None, invocationid=None,
              machinepass=None, ntdsguid=None,
              dnspass=None, root=None, nobody=None, users=None, 
              wheel=None, backup=None, aci=None, serverrole=None,
              dom_for_fun_level=None,
              ldap_backend_extra_port=None, ldap_backend_forced_uri=None, backend_type=None,
              sitename=None,
              ol_mmr_urls=None, ol_olc=None, 
              setup_ds_path=None, slapd_path=None, nosync=False,
              ldap_dryrun_mode=False, useeadb=False, am_rodc=False):
    """Provision samba4
    
    :note: caution, this wipes all existing data!
    """

    def setup_path(file):
      return os.path.join(setup_dir, file)

    if domainsid is None:
      domainsid = security.random_sid()
    else:
      domainsid = security.dom_sid(domainsid)

    # create/adapt the group policy GUIDs
    # Default GUID for default policy are described at
    # "How Core Group Policy Works"
    # http://technet.microsoft.com/en-us/library/cc784268%28WS.10%29.aspx
    if policyguid is None:
        policyguid = DEFAULT_POLICY_GUID
    policyguid = policyguid.upper()
    if policyguid_dc is None:
        policyguid_dc = DEFAULT_DC_POLICY_GUID
    policyguid_dc = policyguid_dc.upper()

    if adminpass is None:
        adminpass = samba.generate_random_password(12, 32)
    if krbtgtpass is None:
        krbtgtpass = samba.generate_random_password(128, 255)
    if machinepass is None:
        machinepass  = samba.generate_random_password(128, 255)
    if dnspass is None:
        dnspass = samba.generate_random_password(128, 255)
    if ldapadminpass is None:
        #Make a new, random password between Samba and it's LDAP server
        ldapadminpass=samba.generate_random_password(128, 255)

    if backend_type is None:
        backend_type = "ldb"

    sid_generator = "internal"
    if backend_type == "fedora-ds":
        sid_generator = "backend"

    root_uid = findnss_uid([root or "root"])
    nobody_uid = findnss_uid([nobody or "nobody"])
    users_gid = findnss_gid([users or "users", 'users', 'other', 'staff'])
    if wheel is None:
        wheel_gid = findnss_gid(["wheel", "adm"])
    else:
        wheel_gid = findnss_gid([wheel])
    try:
        bind_gid = findnss_gid(["bind", "named"])
    except KeyError:
        bind_gid = None

    if targetdir is not None:
        smbconf = os.path.join(targetdir, "etc", "smb.conf")
    elif smbconf is None:
        smbconf = samba.param.default_path()
    if not os.path.exists(os.path.dirname(smbconf)):
        os.makedirs(os.path.dirname(smbconf))

    # only install a new smb.conf if there isn't one there already
    if os.path.exists(smbconf):
        # if Samba Team members can't figure out the weird errors
        # loading an empty smb.conf gives, then we need to be smarter.
        # Pretend it just didn't exist --abartlet
        data = open(smbconf, 'r').read()
        data = data.lstrip()
        if data is None or data == "":
            make_smbconf(smbconf, setup_path, hostname, domain, realm,
                         serverrole, targetdir, sid_generator, useeadb)
    else: 
        make_smbconf(smbconf, setup_path, hostname, domain, realm, serverrole, 
                     targetdir, sid_generator, useeadb)

    lp = samba.param.LoadParm()
    lp.load(smbconf)

    names = guess_names(lp=lp, hostname=hostname, domain=domain,
                        dnsdomain=realm, serverrole=serverrole,
                        domaindn=domaindn, configdn=configdn, schemadn=schemadn,
                        serverdn=serverdn, sitename=sitename)

    paths = provision_paths_from_lp(lp, names.dnsdomain)

    paths.bind_gid = bind_gid

    if hostip is None:
        hostips = samba.interface_ips(lp, False)
        if len(hostips) == 0:
            logger.warning("No external IPv4 address has been found. Using loopback.")
            hostip = '127.0.0.1'
        else:
            hostip = hostips[0]
            if len(hostips) > 1:
                logger.warning("More than one IPv4 address found. Using %s.", hostip)

    if hostip6 is None:
        try:
            for ip in socket.getaddrinfo(names.hostname, None, socket.AF_INET6, socket.AI_CANONNAME, socket.IPPROTO_IP):
                if hostip6 is None:
                    hostip6 = ip[-1][0]
                if hostip6 == '::1' and ip[-1][0] != '::1':
                    hostip6 = ip[-1][0]
        except socket.gaierror, (socket.EAI_NODATA, msg): 
            hostip6 = None

    if serverrole is None:
        serverrole = lp.get("server role")

    assert serverrole in ("domain controller", "member server", "standalone")
    if invocationid is None:
        invocationid = str(uuid.uuid4())

    if not os.path.exists(paths.private_dir):
        os.mkdir(paths.private_dir)
    if not os.path.exists(os.path.join(paths.private_dir, "tls")):
        os.mkdir(os.path.join(paths.private_dir, "tls"))

    ldapi_url = "ldapi://%s" % urllib.quote(paths.s4_ldapi_path, safe="")
 
    schema = Schema(setup_path, domainsid, invocationid=invocationid, schemadn=names.schemadn)

    if backend_type == "ldb":
        provision_backend = LDBBackend(backend_type,
                                       paths=paths, setup_path=setup_path,
                                       lp=lp, credentials=credentials, 
                                       names=names,
                                       logger=logger)
    elif backend_type == "existing":
        provision_backend = ExistingBackend(backend_type,
                                            paths=paths, setup_path=setup_path,
                                            lp=lp, credentials=credentials, 
                                            names=names,
                                            logger=logger,
                                            ldap_backend_forced_uri=ldap_backend_forced_uri)
    elif backend_type == "fedora-ds":
        provision_backend = FDSBackend(backend_type,
                                       paths=paths, setup_path=setup_path,
                                       lp=lp, credentials=credentials, 
                                       names=names,
                                       logger=logger,
                                       domainsid=domainsid,
                                       schema=schema,
                                       hostname=hostname,
                                       ldapadminpass=ldapadminpass,
                                       slapd_path=slapd_path,
                                       ldap_backend_extra_port=ldap_backend_extra_port,
                                       ldap_dryrun_mode=ldap_dryrun_mode,
                                       root=root,
                                       setup_ds_path=setup_ds_path,
                                       ldap_backend_forced_uri=ldap_backend_forced_uri)
    elif backend_type == "openldap":
        provision_backend = OpenLDAPBackend(backend_type,
                                            paths=paths, setup_path=setup_path,
                                            lp=lp, credentials=credentials, 
                                            names=names,
                                            logger=logger,
                                            domainsid=domainsid,
                                            schema=schema,
                                            hostname=hostname,
                                            ldapadminpass=ldapadminpass,
                                            slapd_path=slapd_path,
                                            ldap_backend_extra_port=ldap_backend_extra_port,
                                            ldap_dryrun_mode=ldap_dryrun_mode,
                                            ol_mmr_urls=ol_mmr_urls, 
                                            nosync=nosync,
                                            ldap_backend_forced_uri=ldap_backend_forced_uri)
    else:
        raise ValueError("Unknown LDAP backend type selected")

    provision_backend.init()
    provision_backend.start()

    # only install a new shares config db if there is none
    if not os.path.exists(paths.shareconf):
        logger.info("Setting up share.ldb")
        share_ldb = Ldb(paths.shareconf, session_info=session_info, 
                        lp=lp)
        share_ldb.load_ldif_file_add(setup_path("share.ldif"))

    logger.info("Setting up secrets.ldb")
    secrets_ldb = setup_secretsdb(paths, setup_path,
        session_info=session_info,
        backend_credentials=provision_backend.secrets_credentials, lp=lp)

    try:
        logger.info("Setting up the registry")
        setup_registry(paths.hklm, setup_path, session_info, 
                       lp=lp)

        logger.info("Setting up the privileges database")
        setup_privileges(paths.privilege, setup_path, session_info, lp=lp)

        logger.info("Setting up idmap db")
        idmap = setup_idmapdb(paths.idmapdb, setup_path, session_info=session_info,
                              lp=lp)

        logger.info("Setting up SAM db")
        samdb = setup_samdb(paths.samdb, setup_path, session_info, 
                            provision_backend, lp, names,
                            logger=logger, 
                            domainsid=domainsid, 
                            schema=schema, domainguid=domainguid,
                            policyguid=policyguid, policyguid_dc=policyguid_dc,
                            fill=samdb_fill, 
                            adminpass=adminpass, krbtgtpass=krbtgtpass,
                            invocationid=invocationid, 
                            machinepass=machinepass, dnspass=dnspass, 
                            ntdsguid=ntdsguid, serverrole=serverrole,
                            dom_for_fun_level=dom_for_fun_level,
                            am_rodc=am_rodc, next_rid=next_rid)

        if serverrole == "domain controller":
            if paths.netlogon is None:
                logger.info("Existing smb.conf does not have a [netlogon] share, but you are configuring a DC.")
                logger.info("Please either remove %s or see the template at %s" % 
                        (paths.smbconf, setup_path("provision.smb.conf.dc")))
                assert paths.netlogon is not None

            if paths.sysvol is None:
                logger.info("Existing smb.conf does not have a [sysvol] share, but you"
                        " are configuring a DC.")
                logger.info("Please either remove %s or see the template at %s" % 
                        (paths.smbconf, setup_path("provision.smb.conf.dc")))
                assert paths.sysvol is not None

            if not os.path.isdir(paths.netlogon):
                os.makedirs(paths.netlogon, 0755)

        if samdb_fill == FILL_FULL:
            setup_name_mappings(samdb, idmap, str(domainsid), names.domaindn,
                                root_uid=root_uid, nobody_uid=nobody_uid,
                                users_gid=users_gid, wheel_gid=wheel_gid)

            if serverrole == "domain controller":
                # Set up group policies (domain policy and domain controller policy)
                create_default_gpo(paths.sysvol, names.dnsdomain, policyguid, policyguid_dc)
                setsysvolacl(samdb, paths.netlogon, paths.sysvol, wheel_gid, 
                             domainsid, names.dnsdomain, names.domaindn, lp)

            logger.info("Setting up sam.ldb rootDSE marking as synchronized")
            setup_modify_ldif(samdb, setup_path("provision_rootdse_modify.ldif"))

            secretsdb_self_join(secrets_ldb, domain=names.domain,
                                realm=names.realm,
                                dnsdomain=names.dnsdomain,
                                netbiosname=names.netbiosname,
                                domainsid=domainsid, 
                                machinepass=machinepass,
                                secure_channel_type=SEC_CHAN_BDC)

            # Now set up the right msDS-SupportedEncryptionTypes into the DB
            # In future, this might be determined from some configuration
            kerberos_enctypes = str(ENC_ALL_TYPES)

            try:
                msg = ldb.Message(ldb.Dn(samdb, samdb.searchone("distinguishedName", expression="samAccountName=%s$" % names.netbiosname, scope=ldb.SCOPE_SUBTREE)))
                msg["msDS-SupportedEncryptionTypes"] = ldb.MessageElement(elements=kerberos_enctypes, 
                                                                          flags=ldb.FLAG_MOD_REPLACE, 
                                                                          name="msDS-SupportedEncryptionTypes")
                samdb.modify(msg)
            except ldb.LdbError, (ldb.ERR_NO_SUCH_ATTRIBUTE, _):
                # It might be that this attribute does not exist in this schema
                pass


            if serverrole == "domain controller":
                secretsdb_setup_dns(secrets_ldb, setup_path, names,
                                    paths.private_dir,
                                    realm=names.realm, dnsdomain=names.dnsdomain,
                                    dns_keytab_path=paths.dns_keytab,
                                    dnspass=dnspass)

                domainguid = samdb.searchone(basedn=domaindn, attribute="objectGUID")
                assert isinstance(domainguid, str)

                # Only make a zone file on the first DC, it should be replicated
                # with DNS replication
                create_zone_file(lp, logger, paths, targetdir, setup_path,
                    dnsdomain=names.dnsdomain, hostip=hostip, hostip6=hostip6,
                    hostname=names.hostname, realm=names.realm, 
                    domainguid=domainguid, ntdsguid=names.ntdsguid)

                create_named_conf(paths, setup_path, realm=names.realm,
                                  dnsdomain=names.dnsdomain, private_dir=paths.private_dir)

                create_named_txt(paths.namedtxt, setup_path, realm=names.realm,
                                  dnsdomain=names.dnsdomain, private_dir=paths.private_dir,
                                  keytab_name=paths.dns_keytab)
                logger.info("See %s for an example configuration include file for BIND", paths.namedconf)
                logger.info("and %s for further documentation required for secure DNS "
                        "updates", paths.namedtxt)

            lastProvisionUSNs = get_last_provision_usn(samdb)
            maxUSN = get_max_usn(samdb, str(names.rootdn))
            if lastProvisionUSNs is not None:
                update_provision_usn(samdb, 0, maxUSN, 1)
            else:
                set_provision_usn(samdb, 0, maxUSN)

        create_krb5_conf(paths.krb5conf, setup_path,
                         dnsdomain=names.dnsdomain, hostname=names.hostname,
                         realm=names.realm)
        logger.info("A Kerberos configuration suitable for Samba 4 has been "
                    "generated at %s", paths.krb5conf)

        if serverrole == "domain controller":
            create_dns_update_list(lp, logger, paths, setup_path)

        provision_backend.post_setup()
        provision_backend.shutdown()

        create_phpldapadmin_config(paths.phpldapadminconfig, setup_path, 
                                   ldapi_url)
    except:
        secrets_ldb.transaction_cancel()
        raise

    #Now commit the secrets.ldb to disk
    secrets_ldb.transaction_commit()

    # the commit creates the dns.keytab, now chown it
    dns_keytab_path = os.path.join(paths.private_dir, paths.dns_keytab)
    if (os.path.isfile(dns_keytab_path) and paths.bind_gid is not None):
        try:
            os.chmod(dns_keytab_path, 0640)
            os.chown(dns_keytab_path, -1, paths.bind_gid)
        except OSError:
            if not os.environ.has_key('SAMBA_SELFTEST'):
                logger.info("Failed to chown %s to bind gid %u", dns_keytab_path,
                            paths.bind_gid)


    logger.info("Please install the phpLDAPadmin configuration located at %s into /etc/phpldapadmin/config.php",
            paths.phpldapadminconfig)

    logger.info("Once the above files are installed, your Samba4 server will be ready to use")
    logger.info("Server Role:           %s" % serverrole)
    logger.info("Hostname:              %s" % names.hostname)
    logger.info("NetBIOS Domain:        %s" % names.domain)
    logger.info("DNS Domain:            %s" % names.dnsdomain)
    logger.info("DOMAIN SID:            %s" % str(domainsid))
    if samdb_fill == FILL_FULL:
        logger.info("Admin password:        %s" % adminpass)
    if provision_backend.type is not "ldb":
        if provision_backend.credentials.get_bind_dn() is not None:
            logger.info("LDAP Backend Admin DN: %s" % provision_backend.credentials.get_bind_dn())
        else:
            logger.info("LDAP Admin User:       %s" % provision_backend.credentials.get_username())

        logger.info("LDAP Admin Password:   %s" % provision_backend.credentials.get_password())

        if provision_backend.slapd_command_escaped is not None:
            # now display slapd_command_file.txt to show how slapd must be started next time
            logger.info("Use later the following commandline to start slapd, then Samba:")
            logger.info(provision_backend.slapd_command_escaped)
            logger.info("This slapd-Commandline is also stored under: %s/ldap_backend_startup.sh", 
                    provision_backend.ldapdir)

    result = ProvisionResult()
    result.domaindn = domaindn
    result.paths = paths
    result.lp = lp
    result.samdb = samdb
    return result


def provision_become_dc(setup_dir=None,
                        smbconf=None, targetdir=None, realm=None, 
                        rootdn=None, domaindn=None, schemadn=None,
                        configdn=None, serverdn=None,
                        domain=None, hostname=None, domainsid=None, 
                        adminpass=None, krbtgtpass=None, domainguid=None, 
                        policyguid=None, policyguid_dc=None, invocationid=None,
                        machinepass=None, 
                        dnspass=None, root=None, nobody=None, users=None, 
                        wheel=None, backup=None, serverrole=None, 
                        ldap_backend=None, ldap_backend_type=None,
                        sitename=None, debuglevel=1):

    logger = logging.getLogger("provision")
    samba.set_debug_level(debuglevel)

    res = provision(setup_dir, logger, system_session(), None,
                    smbconf=smbconf, targetdir=targetdir, samdb_fill=FILL_DRS,
                    realm=realm, rootdn=rootdn, domaindn=domaindn, schemadn=schemadn,
                    configdn=configdn, serverdn=serverdn, domain=domain,
                    hostname=hostname, hostip="127.0.0.1", domainsid=domainsid,
                    machinepass=machinepass, serverrole="domain controller",
                    sitename=sitename)
    res.lp.set("debuglevel", str(debuglevel))
    return res


def create_phpldapadmin_config(path, setup_path, ldapi_uri):
    """Create a PHP LDAP admin configuration file.

    :param path: Path to write the configuration to.
    :param setup_path: Function to generate setup paths.
    """
    setup_file(setup_path("phpldapadmin-config.php"), path, 
            {"S4_LDAPI_URI": ldapi_uri})


def create_zone_file(lp, logger, paths, targetdir, setup_path, dnsdomain,
                     hostip, hostip6, hostname, realm, domainguid,
                     ntdsguid):
    """Write out a DNS zone file, from the info in the current database.

    :param paths: paths object
    :param setup_path: Setup path function.
    :param dnsdomain: DNS Domain name
    :param domaindn: DN of the Domain
    :param hostip: Local IPv4 IP
    :param hostip6: Local IPv6 IP
    :param hostname: Local hostname
    :param realm: Realm name
    :param domainguid: GUID of the domain.
    :param ntdsguid: GUID of the hosts nTDSDSA record.
    """
    assert isinstance(domainguid, str)

    if hostip6 is not None:
        hostip6_base_line = "            IN AAAA    " + hostip6
        hostip6_host_line = hostname + "        IN AAAA    " + hostip6
        gc_msdcs_ip6_line = "gc._msdcs               IN AAAA    " + hostip6
    else:
        hostip6_base_line = ""
        hostip6_host_line = ""
        gc_msdcs_ip6_line = ""

    if hostip is not None:
        hostip_base_line = "            IN A    " + hostip
        hostip_host_line = hostname + "        IN A    " + hostip
        gc_msdcs_ip_line = "gc._msdcs               IN A    " + hostip
    else:
        hostip_base_line = ""
        hostip_host_line = ""
        gc_msdcs_ip_line = ""

    dns_dir = os.path.dirname(paths.dns)

    try:
        shutil.rmtree(dns_dir, True)
    except OSError:
        pass

    os.mkdir(dns_dir, 0775)

    # we need to freeze the zone while we update the contents
    if targetdir is None:
        rndc = ' '.join(lp.get("rndc command"))
        os.system(rndc + " freeze " + lp.get("realm"))

    setup_file(setup_path("provision.zone"), paths.dns, {
            "HOSTNAME": hostname,
            "DNSDOMAIN": dnsdomain,
            "REALM": realm,
            "HOSTIP_BASE_LINE": hostip_base_line,
            "HOSTIP_HOST_LINE": hostip_host_line,
            "DOMAINGUID": domainguid,
            "DATESTRING": time.strftime("%Y%m%d%H"),
            "DEFAULTSITE": DEFAULTSITE,
            "NTDSGUID": ntdsguid,
            "HOSTIP6_BASE_LINE": hostip6_base_line,
            "HOSTIP6_HOST_LINE": hostip6_host_line,
            "GC_MSDCS_IP_LINE": gc_msdcs_ip_line,
            "GC_MSDCS_IP6_LINE": gc_msdcs_ip6_line,
        })

    # note that we use no variable substitution on this file
    # the substitution is done at runtime by samba_dnsupdate
    setup_file(setup_path("dns_update_list"), paths.dns_update_list, None)

    # and the SPN update list
    setup_file(setup_path("spn_update_list"), paths.spn_update_list, None)

    if paths.bind_gid is not None:
        try:
            os.chown(dns_dir, -1, paths.bind_gid)
            os.chown(paths.dns, -1, paths.bind_gid)
            # chmod needed to cope with umask
            os.chmod(dns_dir, 0775)
            os.chmod(paths.dns, 0664)
        except OSError:
            if not os.environ.has_key('SAMBA_SELFTEST'):
                logger.error("Failed to chown %s to bind gid %u" % (dns_dir, paths.bind_gid))

    if targetdir is None:
        os.system(rndc + " unfreeze " + lp.get("realm"))


def create_dns_update_list(lp, logger, paths, setup_path):
    """Write out a dns_update_list file"""
    # note that we use no variable substitution on this file
    # the substitution is done at runtime by samba_dnsupdate
    setup_file(setup_path("dns_update_list"), paths.dns_update_list, None)
    setup_file(setup_path("spn_update_list"), paths.spn_update_list, None)


def create_named_conf(paths, setup_path, realm, dnsdomain,
                      private_dir):
    """Write out a file containing zone statements suitable for inclusion in a
    named.conf file (including GSS-TSIG configuration).
    
    :param paths: all paths
    :param setup_path: Setup path function.
    :param realm: Realm name
    :param dnsdomain: DNS Domain name
    :param private_dir: Path to private directory
    :param keytab_name: File name of DNS keytab file
    """

    setup_file(setup_path("named.conf"), paths.namedconf, {
            "DNSDOMAIN": dnsdomain,
            "REALM": realm,
            "ZONE_FILE": paths.dns,
            "REALM_WC": "*." + ".".join(realm.split(".")[1:]),
            "NAMED_CONF": paths.namedconf,
            "NAMED_CONF_UPDATE": paths.namedconf_update
            })

    setup_file(setup_path("named.conf.update"), paths.namedconf_update)


def create_named_txt(path, setup_path, realm, dnsdomain,
                      private_dir, keytab_name):
    """Write out a file containing zone statements suitable for inclusion in a
    named.conf file (including GSS-TSIG configuration).
    
    :param path: Path of the new named.conf file.
    :param setup_path: Setup path function.
    :param realm: Realm name
    :param dnsdomain: DNS Domain name
    :param private_dir: Path to private directory
    :param keytab_name: File name of DNS keytab file
    """

    setup_file(setup_path("named.txt"), path, {
            "DNSDOMAIN": dnsdomain,
            "REALM": realm,
            "DNS_KEYTAB": keytab_name,
            "DNS_KEYTAB_ABS": os.path.join(private_dir, keytab_name),
            "PRIVATE_DIR": private_dir
        })


def create_krb5_conf(path, setup_path, dnsdomain, hostname, realm):
    """Write out a file containing zone statements suitable for inclusion in a
    named.conf file (including GSS-TSIG configuration).
    
    :param path: Path of the new named.conf file.
    :param setup_path: Setup path function.
    :param dnsdomain: DNS Domain name
    :param hostname: Local hostname
    :param realm: Realm name
    """
    setup_file(setup_path("krb5.conf"), path, {
            "DNSDOMAIN": dnsdomain,
            "HOSTNAME": hostname,
            "REALM": realm,
        })


class ProvisioningError(Exception):
    """A generic provision error."""

    def __init__(self, value):
        self.value = value

    def __str__(self):
        return "ProvisioningError: " + self.value


class InvalidNetbiosName(Exception):
    """A specified name was not a valid NetBIOS name."""
    def __init__(self, name):
        super(InvalidNetbiosName, self).__init__("The name '%r' is not a valid NetBIOS name" % name)