Db.cpp@ 82968

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1	/* $Id: Db.cpp 82968 2020-02-04 10:35:17Z vboxsync $ */
2	/** @file
3	* DHCP server - address database
4	*/
5
6	/*
7	* Copyright (C) 2017-2020 Oracle Corporation
8	*
9	* This file is part of VirtualBox Open Source Edition (OSE), as
10	* available from http://www.virtualbox.org. This file is free software;
11	* you can redistribute it and/or modify it under the terms of the GNU
12	* General Public License (GPL) as published by the Free Software
13	* Foundation, in version 2 as it comes in the "COPYING" file of the
14	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16	*/
17
18
19	/*********************************************************************************************************************************
20	* Header Files *
21	*********************************************************************************************************************************/
22	#include "DhcpdInternal.h"
23	#include <iprt/errcore.h>
24
25	#include "Db.h"
26
27
28	/*********************************************************************************************************************************
29	* Global Variables *
30	*********************************************************************************************************************************/
31	/** Indicates whether has been called successfully yet. */
32	bool Binding::g_fFormatRegistered = false;
33
34
35	/**
36	* Registers the ClientId format type callback ("%R[binding]").
37	*/
38	void Binding::registerFormat() RT_NOEXCEPT
39	{
40	if (!g_fFormatRegistered)
41	{
42	int rc = RTStrFormatTypeRegister("binding", rtStrFormat, NULL);
43	AssertRC(rc);
44	g_fFormatRegistered = true;
45	}
46	}
47
48
49	/**
50	* @callback_method_impl{FNRTSTRFORMATTYPE, Formats ClientId via "%R[binding]".}
51	*/
52	DECLCALLBACK(size_t)
53	Binding::rtStrFormat(PFNRTSTROUTPUT pfnOutput, void *pvArgOutput,
54	const char pszType, void const pvValue,
55	int cchWidth, int cchPrecision, unsigned fFlags,
56	void *pvUser)
57	{
58
59	AssertReturn(strcmp(pszType, "binding") == 0, 0);
60	RT_NOREF(pszType);
61
62	RT_NOREF(cchWidth, cchPrecision, fFlags);
63	RT_NOREF(pvUser);
64
65	const Binding b = static_cast<const Binding >(pvValue);
66	if (b == NULL)
67	return pfnOutput(pvArgOutput, RT_STR_TUPLE("<NULL>"));
68
69	size_t cb = RTStrFormat(pfnOutput, pvArgOutput, NULL, 0, "%RTnaipv4", b->m_addr.u);
70	if (b->m_state == Binding::FREE)
71	cb += pfnOutput(pvArgOutput, RT_STR_TUPLE(" free"));
72	else if (b->m_fFixed)
73	cb += pfnOutput(pvArgOutput, RT_STR_TUPLE(" fixed"));
74	else
75	{
76	cb += RTStrFormat(pfnOutput, pvArgOutput, NULL, 0, " to %R[id], %s, valid from ", &b->m_id, b->stateName());
77
78	Timestamp tsIssued = b->issued();
79	cb += tsIssued.strFormatHelper(pfnOutput, pvArgOutput);
80
81	cb += RTStrFormat(pfnOutput, pvArgOutput, NULL, 0, " for %ds until ", b->leaseTime());
82
83	Timestamp tsValid = b->issued();
84	tsValid.addSeconds(b->leaseTime());
85	cb += tsValid.strFormatHelper(pfnOutput, pvArgOutput);
86	}
87
88	return cb;
89	}
90
91
92	/**
93	* Used to update the client ID of a fixed address assignment.
94	*
95	* We only have the MAC address when prepraring the binding, so the full client
96	* ID must be supplied when the client requests it.
97	*
98	* @param a_ridClient The client ID.
99	* @throws std::bad_alloc
100	*/
101	void Binding::idUpdate(const ClientId &a_ridClient)
102	{
103	AssertReturnVoid(isFixed());
104	m_id = a_ridClient;
105	}
106
107
108	/**
109	* Get the state as a string for the XML lease database.
110	*/
111	const char *Binding::stateName() const RT_NOEXCEPT
112	{
113	switch (m_state)
114	{
115	case FREE:
116	return "free";
117	case RELEASED:
118	return "released";
119	case EXPIRED:
120	return "expired";
121	case OFFERED:
122	return "offered";
123	case ACKED:
124	return "acked";
125	default:
126	AssertMsgFailed(("%d\n", m_state));
127	return "released";
128	}
129	}
130
131
132	/**
133	* Sets the state by name (reverse of Binding::stateName()).
134	*/
135	Binding &Binding::setState(const char *pszStateName) RT_NOEXCEPT
136	{
137	if (strcmp(pszStateName, "free") == 0)
138	m_state = Binding::FREE;
139	else if (strcmp(pszStateName, "released") == 0)
140	m_state = Binding::RELEASED;
141	else if (strcmp(pszStateName, "expired") == 0)
142	m_state = Binding::EXPIRED;
143	else if (strcmp(pszStateName, "offered") == 0)
144	m_state = Binding::OFFERED;
145	else if (strcmp(pszStateName, "acked") == 0)
146	m_state = Binding::ACKED;
147	else
148	{
149	AssertMsgFailed(("%d\n", m_state));
150	m_state = Binding::RELEASED;
151	}
152
153	return *this;
154	}
155
156
157	/**
158	* Expires the binding if it's past the specified deadline.
159	*
160	* @returns False if already expired, released or freed, otherwise true (i.e.
161	* does not indicate whether action was taken or not).
162	* @param tsDeadline The expiry deadline to use.
163	*/
164	bool Binding::expire(Timestamp tsDeadline) RT_NOEXCEPT
165	{
166	if (m_state <= Binding::EXPIRED \|\| m_fFixed)
167	return false;
168
169	Timestamp tsExpire = m_issued;
170	tsExpire.addSeconds(m_secLease);
171
172	if (tsExpire < tsDeadline)
173	{
174	if (m_state == Binding::OFFERED)
175	setState(Binding::FREE);
176	else
177	setState(Binding::EXPIRED);
178	}
179	return true;
180	}
181
182
183	/**
184	* Serializes the binding to XML for the lease database.
185	*
186	* @throw std::bad_alloc
187	* @note DHCPServerImpl.cpp contains a reader, keep it in sync.
188	*/
189	void Binding::toXML(xml::ElementNode *pElmParent) const
190	{
191	/*
192	* Lease
193	*/
194	xml::ElementNode *pElmLease = pElmParent->createChild("Lease");
195
196	pElmLease->setAttribute("mac", RTCStringFmt("%RTmac", &m_id.mac()));
197	if (m_id.id().present())
198	{
199	/* I'd prefer RTSTRPRINTHEXBYTES_F_SEP_COLON but there's no decoder */
200	size_t cbStrId = m_id.id().value().size() * 2 + 1;
201	char *pszId = new char[cbStrId];
202	int rc = RTStrPrintHexBytes(pszId, cbStrId,
203	&m_id.id().value().front(), m_id.id().value().size(),
204	0);
205	AssertRC(rc);
206	pElmLease->setAttribute("id", pszId);
207	delete[] pszId;
208	}
209
210	/* unused but we need it to keep the old code happy */
211	pElmLease->setAttribute("network", "0.0.0.0");
212	pElmLease->setAttribute("state", stateName());
213
214	/*
215	* Lease/Address
216	*/
217	xml::ElementNode *pElmAddr = pElmLease->createChild("Address");
218	pElmAddr->setAttribute("value", RTCStringFmt("%RTnaipv4", m_addr.u));
219
220	/*
221	* Lease/Time
222	*/
223	xml::ElementNode *pElmTime = pElmLease->createChild("Time");
224	pElmTime->setAttribute("issued", m_issued.getAbsSeconds());
225	pElmTime->setAttribute("expiration", m_secLease);
226	}
227
228
229	/**
230	* Deserializes the binding from the XML lease database.
231	*
232	* @param pElmLease The "Lease" element to serialize into.
233	* @return Pointer to the resulting binding, NULL on failure.
234	* @throw std::bad_alloc
235	* @note DHCPServerImpl.cpp contains a similar reader, keep it in sync.
236	*/
237	Binding Binding::fromXML(const xml::ElementNode pElmLease)
238	{
239	/* Note! Lease/@network seems to always have bogus value, ignore it. */
240	/* Note! We parse the mandatory attributes and elements first, then
241	the optional ones. This means things appear a little jumbled. */
242
243	/*
244	* Lease/@mac - mandatory.
245	*/
246	const char *pszMacAddress = pElmLease->findAttributeValue("mac");
247	if (!pszMacAddress)
248	DHCP_LOG_RET_NULL(("Binding::fromXML: <Lease> element without 'mac' attribute! Skipping lease.\n"));
249
250	RTMAC mac;
251	int rc = RTNetStrToMacAddr(pszMacAddress, &mac);
252	if (RT_FAILURE(rc))
253	DHCP_LOG_RET_NULL(("Binding::fromXML: Malformed mac address attribute value '%s': %Rrc - Skipping lease.\n",
254	pszMacAddress, rc));
255
256	/*
257	* Lease/Address/@value - mandatory.
258	*/
259	const char *pszAddress = pElmLease->findChildElementAttributeValue("Address", "value");
260	if (!pszAddress)
261	DHCP_LOG_RET_NULL(("Binding::fromXML: Could not find <Address> with a 'value' attribute! Skipping lease.\n"));
262
263	RTNETADDRIPV4 addr;
264	rc = RTNetStrToIPv4Addr(pszAddress, &addr);
265	if (RT_FAILURE(rc))
266	DHCP_LOG_RET_NULL(("Binding::fromXML: Malformed IPv4 address value '%s': %Rrc - Skipping lease.\n", pszAddress, rc));
267
268	/*
269	* Lease/Time - mandatory.
270	*/
271	const xml::ElementNode *pElmTime = pElmLease->findChildElement("Time");
272	if (pElmTime == NULL)
273	DHCP_LOG_RET_NULL(("Binding::fromXML: No <Time> element under <Lease mac=%RTmac>! Skipping lease.\n", &mac));
274
275	/*
276	* Lease/Time/@issued - mandatory.
277	*/
278	int64_t secIssued;
279	if (!pElmTime->getAttributeValue("issued", &secIssued))
280	DHCP_LOG_RET_NULL(("Binding::fromXML: <Time> element for %RTmac has no valid 'issued' attribute! Skipping lease.\n", &mac));
281
282	/*
283	* Lease/Time/@expiration - mandatory.
284	*/
285	uint32_t cSecToLive;
286	if (!pElmTime->getAttributeValue("expiration", &cSecToLive))
287	DHCP_LOG_RET_NULL(("Binding::fromXML: <Time> element for %RTmac has no valid 'expiration' attribute! Skipping lease.\n", &mac));
288
289	std::unique_ptr<Binding> b(new Binding(addr));
290
291	/*
292	* Lease/@state - mandatory but not present in old leases file, so pretent
293	* we're loading an expired one if absent.
294	*/
295	const char *pszState = pElmLease->findAttributeValue("state");
296	if (pszState)
297	{
298	b->m_issued = Timestamp::absSeconds(secIssued);
299	b->setState(pszState);
300	}
301	else
302	{ /** @todo XXX: old code wrote timestamps instead of absolute time. */
303	/* pretend that lease has just ended */
304	LogRel(("Binding::fromXML: No 'state' attribute for <Lease mac=%RTmac> (ts=%RI64 ttl=%RU32)! Assuming EXPIRED.\n",
305	&mac, secIssued, cSecToLive));
306	b->m_issued = Timestamp::now().subSeconds(cSecToLive);
307	b->m_state = Binding::EXPIRED;
308	}
309	b->m_secLease = cSecToLive;
310
311
312	/*
313	* Lease/@id - optional, ignore if bad.
314	* Value format: "deadbeef..." or "de:ad:be:ef...".
315	*/
316	const char *pszClientId = pElmLease->findAttributeValue("id");
317	if (pszClientId)
318	{
319	uint8_t abBytes[255];
320	size_t cbActual;
321	rc = RTStrConvertHexBytesEx(pszClientId, abBytes, sizeof(abBytes), RTSTRCONVERTHEXBYTES_F_SEP_COLON, NULL, &cbActual);
322	if (RT_SUCCESS(rc))
323	{
324	b->m_id = ClientId(mac, OptClientId(std::vector<uint8_t>(&abBytes[0], &abBytes[cbActual]))); /* throws bad_alloc */
325	if (rc != VINF_BUFFER_UNDERFLOW && rc != VINF_SUCCESS)
326	LogRel(("Binding::fromXML: imperfect 'id' attribute: rc=%Rrc, cbActual=%u, '%s'\n", rc, cbActual, pszClientId));
327	}
328	else
329	{
330	LogRel(("Binding::fromXML: ignoring malformed 'id' attribute: rc=%Rrc, cbActual=%u, '%s'\n",
331	rc, cbActual, pszClientId));
332	b->m_id = ClientId(mac, OptClientId());
333	}
334	}
335	else
336	b->m_id = ClientId(mac, OptClientId());
337
338	return b.release();
339	}
340
341
342
343	/*********************************************************************************************************************************
344	* Class Db Implementation *
345	*********************************************************************************************************************************/
346
347	Db::Db()
348	: m_pConfig(NULL)
349	{
350	}
351
352
353	Db::~Db()
354	{
355	/** @todo free bindings */
356	}
357
358
359	int Db::init(const Config *pConfig)
360	{
361	Binding::registerFormat();
362
363	m_pConfig = pConfig;
364
365	int rc = m_pool.init(pConfig->getIPv4PoolFirst(), pConfig->getIPv4PoolLast());
366	if (RT_SUCCESS(rc))
367	{
368	/*
369	* If the server IP is in the dynamic range, preallocate it like a fixed assignment.
370	*/
371	rc = i_enterFixedAddressAssignment(pConfig->getIPv4Address(), pConfig->getMacAddress());
372	if (RT_SUCCESS(rc))
373	{
374	/*
375	* Preallocate any fixed address assignments:
376	*/
377	Config::HostConfigVec vecHostConfigs;
378	rc = pConfig->getFixedAddressConfigs(vecHostConfigs);
379	for (Config::HostConfigVec::const_iterator it = vecHostConfigs.begin();
380	it != vecHostConfigs.end() && RT_SUCCESS(rc); ++it)
381	rc = i_enterFixedAddressAssignment((it)->getFixedAddress(), (it)->getMACAddress());
382	}
383	}
384
385	return rc;
386	}
387
388
389	/**
390	* Used by Db::init() to register a fixed address assignment.
391	*
392	* @returns IPRT status code.
393	* @param a_rAddress The IPv4 address assignment.
394	* @param a_rMACAddress The MAC address.
395	*/
396	int Db::i_enterFixedAddressAssignment(RTNETADDRIPV4 const &a_rAddress, RTMAC const &a_rMACAddress) RT_NOEXCEPT
397	{
398	LogRelFunc(("%RTmac: %RTnaipv4\n", &a_rMACAddress, a_rAddress));
399	Assert(m_pConfig->isInIPv4Network(a_rAddress)); /* should've been checked elsewhere already */
400
401	/*
402	* If the address is part of the pool, we have to allocate it to
403	* prevent it from being used again.
404	*/
405	if (m_pool.contains(a_rAddress))
406	{
407	if (!m_pool.allocate(a_rAddress))
408	{
409	LogRelFunc(("%RTnaipv4 already allocated?\n", a_rAddress));
410	return VERR_ADDRESS_CONFLICT;
411	}
412	}
413
414	/*
415	* Create the binding.
416	*/
417	Binding *pBinding = NULL;
418	try
419	{
420	pBinding = new Binding(a_rAddress, a_rMACAddress, true /fFixed/);
421	m_bindings.push_front(pBinding);
422	}
423	catch (std::bad_alloc &)
424	{
425	if (pBinding)
426	delete pBinding;
427	return VERR_NO_MEMORY;
428	}
429	return VINF_SUCCESS;
430	}
431
432
433	/**
434	* Expire old binding (leases).
435	*/
436	void Db::expire() RT_NOEXCEPT
437	{
438	const Timestamp now = Timestamp::now();
439	for (bindings_t::iterator it = m_bindings.begin(); it != m_bindings.end(); ++it)
440	{
441	Binding b = it;
442	b->expire(now);
443	}
444	}
445
446
447	/**
448	* Internal worker that creates a binding for the given client, allocating new
449	* IPv4 address for it.
450	*
451	* @returns Pointer to the binding.
452	* @param id The client ID.
453	*/
454	Binding *Db::i_createBinding(const ClientId &id)
455	{
456	Binding *pBinding = NULL;
457	RTNETADDRIPV4 addr = m_pool.allocate();
458	if (addr.u != 0)
459	{
460	try
461	{
462	pBinding = new Binding(addr, id);
463	m_bindings.push_front(pBinding);
464	}
465	catch (std::bad_alloc &)
466	{
467	if (pBinding)
468	delete pBinding;
469	/** @todo free address (no pool method for that) */
470	}
471	}
472	return pBinding;
473	}
474
475
476	/**
477	* Internal worker that creates a binding to the specified IPv4 address for the
478	* given client.
479	*
480	* @returns Pointer to the binding.
481	* NULL if the address is in use or we ran out of memory.
482	* @param addr The IPv4 address.
483	* @param id The client.
484	*/
485	Binding *Db::i_createBinding(RTNETADDRIPV4 addr, const ClientId &id)
486	{
487	bool fAvailable = m_pool.allocate(addr);
488	if (!fAvailable)
489	{
490	/** @todo
491	* XXX: this should not happen. If the address is from the
492	* pool, which we have verified before, then either it's in
493	* the free pool or there's an binding (possibly free) for it.
494	*/
495	return NULL;
496	}
497
498	Binding *b = new Binding(addr, id);
499	m_bindings.push_front(b);
500	return b;
501	}
502
503
504	/**
505	* Internal worker that allocates an IPv4 address for the given client, taking
506	* the preferred address (@a addr) into account when possible and if non-zero.
507	*/
508	Binding *Db::i_allocateAddress(const ClientId &id, RTNETADDRIPV4 addr)
509	{
510	Assert(addr.u == 0 \|\| addressBelongs(addr));
511
512	if (addr.u != 0)
513	LogRel(("> allocateAddress %RTnaipv4 to client %R[id]\n", addr.u, &id));
514	else
515	LogRel(("> allocateAddress to client %R[id]\n", &id));
516
517	/*
518	* Allocate existing address if client has one. Ignore requested
519	* address in that case. While here, look for free addresses and
520	* addresses that can be reused.
521	*/
522	Binding *addrBinding = NULL;
523	Binding *freeBinding = NULL;
524	Binding *reuseBinding = NULL;
525	const Timestamp now = Timestamp::now();
526	for (bindings_t::iterator it = m_bindings.begin(); it != m_bindings.end(); ++it)
527	{
528	Binding b = it;
529	b->expire(now);
530
531	/*
532	* We've already seen this client, give it its old binding.
533	*
534	* If the client's MAC address is configured with a fixed
535	* address, give its preconfigured binding. Fixed bindings
536	* are always at the head of the m_bindings list, so we
537	* won't be confused by any old leases of the client.
538	*/
539	if (b->m_id == id)
540	{
541	LogRel(("> ... found existing binding %R[binding]\n", b));
542	return b;
543	}
544	if (b->isFixed() && b->id().mac() == id.mac())
545	{
546	b->idUpdate(id);
547	LogRel(("> ... found fixed binding %R[binding]\n", b));
548	return b;
549	}
550
551	if (addr.u != 0 && b->m_addr.u == addr.u)
552	{
553	Assert(addrBinding == NULL);
554	addrBinding = b;
555	LogRel(("> .... noted existing binding %R[binding]\n", addrBinding));
556	}
557
558	/* if we haven't found a free binding yet, keep looking */
559	if (freeBinding == NULL)
560	{
561	if (b->m_state == Binding::FREE)
562	{
563	freeBinding = b;
564	LogRel(("> .... noted free binding %R[binding]\n", freeBinding));
565	continue;
566	}
567
568	/* still no free binding, can this one be reused? */
569	if (b->m_state == Binding::RELEASED)
570	{
571	if ( reuseBinding == NULL
572	/* released binding is better than an expired one */
573	\|\| reuseBinding->m_state == Binding::EXPIRED)
574	{
575	reuseBinding = b;
576	LogRel(("> .... noted released binding %R[binding]\n", reuseBinding));
577	}
578	}
579	else if (b->m_state == Binding::EXPIRED)
580	{
581	if ( reuseBinding == NULL
582	/* long expired binding is bettern than a recent one */
583	/* \|\| (reuseBinding->m_state == Binding::EXPIRED && b->olderThan(reuseBinding)) */)
584	{
585	reuseBinding = b;
586	LogRel(("> .... noted expired binding %R[binding]\n", reuseBinding));
587	}
588	}
589	}
590	}
591
592	/*
593	* Allocate requested address if we can.
594	*/
595	if (addr.u != 0)
596	{
597	if (addrBinding == NULL)
598	{
599	addrBinding = i_createBinding(addr, id);
600	Assert(addrBinding != NULL);
601	LogRel(("> .... creating new binding for this address %R[binding]\n", addrBinding));
602	return addrBinding;
603	}
604
605	if (addrBinding->m_state <= Binding::EXPIRED) /* not in use */
606	{
607	LogRel(("> .... reusing %s binding for this address\n", addrBinding->stateName()));
608	addrBinding->giveTo(id);
609	return addrBinding;
610	}
611	LogRel(("> .... cannot reuse %s binding for this address\n", addrBinding->stateName()));
612	}
613
614	/*
615	* Allocate new (or reuse).
616	*/
617	Binding *idBinding = NULL;
618	if (freeBinding != NULL)
619	{
620	idBinding = freeBinding;
621	LogRel(("> .... reusing free binding\n"));
622	}
623	else
624	{
625	idBinding = i_createBinding();
626	if (idBinding != NULL)
627	LogRel(("> .... creating new binding\n"));
628	else
629	{
630	idBinding = reuseBinding;
631	if (idBinding != NULL)
632	LogRel(("> .... reusing %s binding %R[binding]\n", reuseBinding->stateName(), reuseBinding));
633	else
634	DHCP_LOG_RET_NULL(("> .... failed to allocate binding\n"));
635	}
636	}
637
638	idBinding->giveTo(id);
639	LogRel(("> .... allocated %R[binding]\n", idBinding));
640
641	return idBinding;
642	}
643
644
645
646	/**
647	* Called by DHCPD to allocate a binding for the specified request.
648	*
649	* @returns Pointer to the binding, NULL on failure.
650	* @param req The DHCP request being served.
651	* @param rConfigVec The configurations that applies to the client.
652	* Used for lease time calculation.
653	*/
654	Binding *Db::allocateBinding(const DhcpClientMessage &req, Config::ConfigVec const &rConfigVec)
655	{
656	const ClientId &id(req.clientId());
657
658	/*
659	* Get and validate the requested address (if present).
660	*
661	* Fixed assignments are often outside the dynamic range, so we much detect
662	* those to make sure they aren't rejected based on IP range. ASSUMES fixed
663	* assignments are at the head of the binding list.
664	*/
665	OptRequestedAddress reqAddr(req);
666	if (reqAddr.present() && !addressBelongs(reqAddr.value()))
667	{
668	bool fIsFixed = false;
669	for (bindings_t::iterator it = m_bindings.begin(); it != m_bindings.end() && (*it)->isFixed(); ++it)
670	if (reqAddr.value().u == (*it)->addr().u)
671	{
672	if ( (*it)->id() == id
673	\|\| (*it)->id().mac() == id.mac())
674	{
675	fIsFixed = true;
676	break;
677	}
678	}
679	if (fIsFixed)
680	reqAddr = OptRequestedAddress();
681	else if (req.messageType() == RTNET_DHCP_MT_DISCOVER)
682	{
683	LogRel(("DISCOVER: ignoring invalid requested address\n"));
684	reqAddr = OptRequestedAddress();
685	}
686	else
687	DHCP_LOG_RET_NULL(("rejecting invalid requested address\n"));
688	}
689
690	/*
691	* Allocate the address.
692	*/
693	Binding *b = i_allocateAddress(id, reqAddr.value());
694	if (b != NULL)
695	{
696	Assert(b->id() == id);
697
698	/*
699	* Figure out the lease time.
700	*/
701	uint32_t secMin = 0;
702	uint32_t secDfl = 0;
703	uint32_t secMax = 0;
704	for (Config::ConfigVec::const_iterator it = rConfigVec.begin(); it != rConfigVec.end(); ++it)
705	{
706	ConfigLevelBase const pConfig = it;
707	if (secMin == 0)
708	secMin = pConfig->getMinLeaseTime();
709	if (secDfl == 0)
710	secDfl = pConfig->getDefaultLeaseTime();
711	if (secMax == 0)
712	secMax = pConfig->getMaxLeaseTime();
713	}
714	Assert(secMin); Assert(secMax); Assert(secDfl); /* global config always have non-defaults set */
715	if (secMin > secMax)
716	secMin = secMax;
717
718	OptLeaseTime reqLeaseTime(req);
719	if (!reqLeaseTime.present())
720	{
721	b->setLeaseTime(secDfl);
722	LogRel2(("Lease time %u secs (default)\n", b->leaseTime()));
723	}
724	else if (reqLeaseTime.value() < secMin)
725	{
726	b->setLeaseTime(secMin);
727	LogRel2(("Lease time %u secs (min)\n", b->leaseTime()));
728	}
729	else if (reqLeaseTime.value() > secMax)
730	{
731	b->setLeaseTime(secMax);
732	LogRel2(("Lease time %u secs (max)\n", b->leaseTime()));
733	}
734	else
735	{
736	b->setLeaseTime(reqLeaseTime.value());
737	LogRel2(("Lease time %u secs (requested)\n", b->leaseTime()));
738	}
739	}
740	return b;
741	}
742
743
744	/**
745	* Internal worker used by loadLease().
746	*
747	* @returns IPRT status code.
748	* @param pNewBinding The new binding to add.
749	*/
750	int Db::i_addBinding(Binding *pNewBinding) RT_NOEXCEPT
751	{
752	/*
753	* Validate the binding against the range and existing bindings.
754	*/
755	if (!addressBelongs(pNewBinding->m_addr))
756	{
757	LogRel(("Binding for out of range address %RTnaipv4 ignored\n", pNewBinding->m_addr.u));
758	return VERR_OUT_OF_RANGE;
759	}
760
761	for (bindings_t::iterator it = m_bindings.begin(); it != m_bindings.end(); ++it)
762	{
763	Binding b = it;
764
765	if (pNewBinding->m_addr.u == b->m_addr.u)
766	{
767	LogRel(("> ADD: %R[binding]\n", pNewBinding));
768	LogRel(("> .... duplicate ip: %R[binding]\n", b));
769	return VERR_DUPLICATE;
770	}
771
772	if (pNewBinding->m_id == b->m_id)
773	{
774	LogRel(("> ADD: %R[binding]\n", pNewBinding));
775	LogRel(("> .... duplicate id: %R[binding]\n", b));
776	return VERR_DUPLICATE;
777	}
778	}
779
780	/*
781	* Allocate the address and add the binding to the list.
782	*/
783	AssertLogRelMsgReturn(m_pool.allocate(pNewBinding->m_addr),
784	("> ADD: failed to claim IP %R[binding]\n", pNewBinding),
785	VERR_INTERNAL_ERROR);
786	try
787	{
788	m_bindings.push_back(pNewBinding);
789	}
790	catch (std::bad_alloc &)
791	{
792	return VERR_NO_MEMORY;
793	}
794	return VINF_SUCCESS;
795	}
796
797
798	/**
799	* Called by DHCP to cancel an offset.
800	*
801	* @param req The DHCP request.
802	*/
803	void Db::cancelOffer(const DhcpClientMessage &req) RT_NOEXCEPT
804	{
805	const OptRequestedAddress reqAddr(req);
806	if (!reqAddr.present())
807	return;
808
809	const RTNETADDRIPV4 addr = reqAddr.value();
810	const ClientId &id(req.clientId());
811
812	for (bindings_t::iterator it = m_bindings.begin(); it != m_bindings.end(); ++it)
813	{
814	Binding b = it;
815
816	if (b->addr().u == addr.u && b->id() == id)
817	{
818	if (b->state() == Binding::OFFERED)
819	{
820	LogRel2(("Db::cancelOffer: cancelling %R[binding]\n", b));
821	if (!b->isFixed())
822	{
823	b->setLeaseTime(0);
824	b->setState(Binding::RELEASED);
825	}
826	else
827	b->setState(Binding::ACKED);
828	}
829	else
830	LogRel2(("Db::cancelOffer: not offered state: %R[binding]\n", b));
831	return;
832	}
833	}
834	LogRel2(("Db::cancelOffer: not found (%RTnaipv4, %R[id])\n", addr.u, &id));
835	}
836
837
838	/**
839	* Called by DHCP to cancel an offset.
840	*
841	* @param req The DHCP request.
842	* @returns true if found and released, otherwise false.
843	* @throws nothing
844	*/
845	bool Db::releaseBinding(const DhcpClientMessage &req) RT_NOEXCEPT
846	{
847	const RTNETADDRIPV4 addr = req.ciaddr();
848	const ClientId &id(req.clientId());
849
850	for (bindings_t::iterator it = m_bindings.begin(); it != m_bindings.end(); ++it)
851	{
852	Binding b = it;
853
854	if (b->addr().u == addr.u && b->id() == id)
855	{
856	LogRel2(("Db::releaseBinding: releasing %R[binding]\n", b));
857	if (!b->isFixed())
858	{
859	b->setState(Binding::RELEASED);
860	return true;
861	}
862	b->setState(Binding::ACKED);
863	return false;
864	}
865	}
866
867	LogRel2(("Db::releaseBinding: not found (%RTnaipv4, %R[id])\n", addr.u, &id));
868	return false;
869	}
870
871
872	/**
873	* Called by DHCPD to write out the lease database to @a strFilename.
874	*
875	* @returns IPRT status code.
876	* @param strFilename The file to write it to.
877	*/
878	int Db::writeLeases(const RTCString &strFilename) const RT_NOEXCEPT
879	{
880	LogRel(("writing leases to %s\n", strFilename.c_str()));
881
882	/** @todo This could easily be written directly to the file w/o going thru
883	* a xml::Document, xml::XmlFileWriter, hammering the heap and being
884	* required to catch a lot of different exceptions at various points.
885	* (RTStrmOpen, bunch of RTStrmPrintf using \%RMas and \%RMes.,
886	* RTStrmClose closely followed by a couple of renames.)
887	*/
888
889	/*
890	* Create the document and root element.
891	*/
892	xml::Document doc;
893	try
894	{
895	xml::ElementNode *pElmRoot = doc.createRootElement("Leases");
896	pElmRoot->setAttribute("version", "1.0");
897
898	/*
899	* Add the leases.
900	*/
901	for (bindings_t::const_iterator it = m_bindings.begin(); it != m_bindings.end(); ++it)
902	{
903	const Binding b = it;
904	if (!b->isFixed())
905	b->toXML(pElmRoot);
906	}
907	}
908	catch (std::bad_alloc &)
909	{
910	return VERR_NO_MEMORY;
911	}
912
913	/*
914	* Write the document to the specified file in a safe manner (written to temporary
915	* file, renamed to destination on success)
916	*/
917	try
918	{
919	xml::XmlFileWriter writer(doc);
920	writer.write(strFilename.c_str(), true /fSafe/);
921	}
922	catch (const xml::EIPRTFailure &e)
923	{
924	LogRel(("%s\n", e.what()));
925	return e.rc();
926	}
927	catch (const RTCError &e)
928	{
929	LogRel(("%s\n", e.what()));
930	return VERR_GENERAL_FAILURE;
931	}
932	catch (...)
933	{
934	LogRel(("Unknown exception while writing '%s'\n", strFilename.c_str()));
935	return VERR_UNEXPECTED_EXCEPTION;
936	}
937
938	return VINF_SUCCESS;
939	}
940
941
942	/**
943	* Called by DHCPD to load the lease database to @a strFilename.
944	*
945	* @note Does not clear the database state before doing the load.
946	*
947	* @returns IPRT status code.
948	* @param strFilename The file to load it from.
949	* @throws nothing
950	*/
951	int Db::loadLeases(const RTCString &strFilename) RT_NOEXCEPT
952	{
953	LogRel(("loading leases from %s\n", strFilename.c_str()));
954
955	/*
956	* Load the file into an XML document.
957	*/
958	xml::Document doc;
959	try
960	{
961	xml::XmlFileParser parser;
962	parser.read(strFilename.c_str(), doc);
963	}
964	catch (const xml::EIPRTFailure &e)
965	{
966	LogRel(("%s\n", e.what()));
967	return e.rc();
968	}
969	catch (const RTCError &e)
970	{
971	LogRel(("%s\n", e.what()));
972	return VERR_GENERAL_FAILURE;
973	}
974	catch (...)
975	{
976	LogRel(("Unknown exception while reading and parsing '%s'\n", strFilename.c_str()));
977	return VERR_UNEXPECTED_EXCEPTION;
978	}
979
980	/*
981	* Check that the root element is "Leases" and process its children.
982	*/
983	xml::ElementNode *pElmRoot = doc.getRootElement();
984	if (!pElmRoot)
985	{
986	LogRel(("No root element in '%s'\n", strFilename.c_str()));
987	return VERR_NOT_FOUND;
988	}
989	if (!pElmRoot->nameEquals("Leases"))
990	{
991	LogRel(("No root element is not 'Leases' in '%s', but '%s'\n", strFilename.c_str(), pElmRoot->getName()));
992	return VERR_NOT_FOUND;
993	}
994
995	int rc = VINF_SUCCESS;
996	xml::NodesLoop it(*pElmRoot);
997	const xml::ElementNode *pElmLease;
998	while ((pElmLease = it.forAllNodes()) != NULL)
999	{
1000	if (pElmLease->nameEquals("Lease"))
1001	{
1002	int rc2 = i_loadLease(pElmLease);
1003	if (RT_SUCCESS(rc2))
1004	{ /* likely */ }
1005	else if (rc2 == VERR_NO_MEMORY)
1006	return rc2;
1007	else
1008	rc = -rc2;
1009	}
1010	else
1011	LogRel(("Ignoring unexpected element '%s' under 'Leases'...\n", pElmLease->getName()));
1012	}
1013
1014	return rc;
1015	}
1016
1017
1018	/**
1019	* Internal worker for loadLeases() that handles one 'Lease' element.
1020	*
1021	* @param pElmLease The 'Lease' element to handle.
1022	* @return IPRT status code.
1023	*/
1024	int Db::i_loadLease(const xml::ElementNode *pElmLease) RT_NOEXCEPT
1025	{
1026	Binding *pBinding = NULL;
1027	try
1028	{
1029	pBinding = Binding::fromXML(pElmLease);
1030	}
1031	catch (std::bad_alloc &)
1032	{
1033	return VERR_NO_MEMORY;
1034	}
1035	if (pBinding)
1036	{
1037	bool fExpired = pBinding->expire();
1038	if (!fExpired)
1039	LogRel(("> LOAD: lease %R[binding]\n", pBinding));
1040	else
1041	LogRel(("> LOAD: EXPIRED lease %R[binding]\n", pBinding));
1042
1043	int rc = i_addBinding(pBinding);
1044	if (RT_FAILURE(rc))
1045	delete pBinding;
1046	return rc;
1047	}
1048	LogRel(("> LOAD: failed to load lease!\n"));
1049	return VERR_PARSE_ERROR;
1050	}

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source: vbox/trunk/src/VBox/NetworkServices/Dhcpd/Db.cpp@ 82968

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