freebsd-nq/contrib/bind9/lib/dns/dlz.c
Doug Barton 6318052d9e Update BIND to version 9.6.1rc1. This version has better performance and
lots of new features compared to 9.4.x, including:

	Full NSEC3 support
	Automatic zone re-signing
	New update-policy methods tcp-self and 6to4-self
	DHCID support.
	More detailed statistics counters including those supported in BIND 8.
	Faster ACL processing.
	Efficient LRU cache-cleaning mechanism.
	NSID support.
2009-05-31 05:42:58 +00:00

511 lines
14 KiB
C

/*
* Portions Copyright (C) 2005, 2007, 2009 Internet Systems Consortium, Inc. ("ISC")
* Portions Copyright (C) 1999-2001 Internet Software Consortium.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
/*
* Copyright (C) 2002 Stichting NLnet, Netherlands, stichting@nlnet.nl.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the
* above copyright notice and this permission notice appear in all
* copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND STICHTING NLNET
* DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
* STICHTING NLNET BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
* OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE
* USE OR PERFORMANCE OF THIS SOFTWARE.
*
* The development of Dynamically Loadable Zones (DLZ) for Bind 9 was
* conceived and contributed by Rob Butler.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the
* above copyright notice and this permission notice appear in all
* copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ROB BUTLER
* DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
* ROB BUTLER BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
* OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE
* USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: dlz.c,v 1.5.332.2 2009/01/18 23:47:35 tbox Exp $ */
/*! \file */
/***
*** Imports
***/
#include <config.h>
#include <dns/fixedname.h>
#include <dns/log.h>
#include <dns/master.h>
#include <dns/dlz.h>
#include <isc/buffer.h>
#include <isc/magic.h>
#include <isc/mem.h>
#include <isc/once.h>
#include <isc/rwlock.h>
#include <isc/string.h>
#include <isc/util.h>
/***
*** Supported DLZ DB Implementations Registry
***/
static ISC_LIST(dns_dlzimplementation_t) dlz_implementations;
static isc_rwlock_t dlz_implock;
static isc_once_t once = ISC_ONCE_INIT;
static void
dlz_initialize(void) {
RUNTIME_CHECK(isc_rwlock_init(&dlz_implock, 0, 0) == ISC_R_SUCCESS);
ISC_LIST_INIT(dlz_implementations);
}
/*%
* Searches the dlz_implementations list for a driver matching name.
*/
static inline dns_dlzimplementation_t *
dlz_impfind(const char *name) {
dns_dlzimplementation_t *imp;
for (imp = ISC_LIST_HEAD(dlz_implementations);
imp != NULL;
imp = ISC_LIST_NEXT(imp, link))
if (strcasecmp(name, imp->name) == 0)
return (imp);
return (NULL);
}
/***
*** Basic DLZ Methods
***/
isc_result_t
dns_dlzallowzonexfr(dns_view_t *view, dns_name_t *name,
isc_sockaddr_t *clientaddr, dns_db_t **dbp)
{
isc_result_t result;
dns_dlzallowzonexfr_t allowzonexfr;
dns_dlzdb_t *dlzdatabase;
/*
* Performs checks to make sure data is as we expect it to be.
*/
REQUIRE(DNS_DLZ_VALID(view->dlzdatabase));
REQUIRE(name != NULL);
REQUIRE(dbp != NULL && *dbp == NULL);
/* ask driver if the zone is supported */
dlzdatabase = view->dlzdatabase;
allowzonexfr = dlzdatabase->implementation->methods->allowzonexfr;
result = (*allowzonexfr)(dlzdatabase->implementation->driverarg,
dlzdatabase->dbdata, dlzdatabase->mctx,
view->rdclass, name, clientaddr, dbp);
if (result == ISC_R_NOTIMPLEMENTED)
return (ISC_R_NOTFOUND);
return (result);
}
isc_result_t
dns_dlzcreate(isc_mem_t *mctx, const char *dlzname, const char *drivername,
unsigned int argc, char *argv[], dns_dlzdb_t **dbp)
{
dns_dlzimplementation_t *impinfo;
isc_result_t result;
/*
* initialize the dlz_implementations list, this is guaranteed
* to only really happen once.
*/
RUNTIME_CHECK(isc_once_do(&once, dlz_initialize) == ISC_R_SUCCESS);
/*
* Performs checks to make sure data is as we expect it to be.
*/
REQUIRE(dbp != NULL && *dbp == NULL);
REQUIRE(dlzname != NULL);
REQUIRE(drivername != NULL);
REQUIRE(mctx != NULL);
/* write log message */
isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE,
DNS_LOGMODULE_DLZ, ISC_LOG_INFO,
"Loading '%s' using driver %s", dlzname, drivername);
/* lock the dlz_implementations list so we can search it. */
RWLOCK(&dlz_implock, isc_rwlocktype_read);
/* search for the driver implementation */
impinfo = dlz_impfind(drivername);
if (impinfo == NULL) {
RWUNLOCK(&dlz_implock, isc_rwlocktype_read);
isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE,
DNS_LOGMODULE_DLZ, ISC_LOG_ERROR,
"unsupported DLZ database driver '%s'."
" %s not loaded.",
drivername, dlzname);
return (ISC_R_NOTFOUND);
}
/* Allocate memory to hold the DLZ database driver */
(*dbp) = isc_mem_get(mctx, sizeof(dns_dlzdb_t));
if ((*dbp) == NULL) {
RWUNLOCK(&dlz_implock, isc_rwlocktype_read);
return (ISC_R_NOMEMORY);
}
/* Make sure memory region is set to all 0's */
memset((*dbp), 0, sizeof(dns_dlzdb_t));
(*dbp)->implementation = impinfo;
/* Create a new database using implementation 'drivername'. */
result = ((impinfo->methods->create)(mctx, dlzname, argc, argv,
impinfo->driverarg,
&(*dbp)->dbdata));
/* mark the DLZ driver as valid */
if (result == ISC_R_SUCCESS) {
RWUNLOCK(&dlz_implock, isc_rwlocktype_read);
(*dbp)->magic = DNS_DLZ_MAGIC;
isc_mem_attach(mctx, &(*dbp)->mctx);
isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE,
DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2),
"DLZ driver loaded successfully.");
return (ISC_R_SUCCESS);
} else {
isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE,
DNS_LOGMODULE_DLZ, ISC_LOG_ERROR,
"DLZ driver failed to load.");
}
/* impinfo->methods->create failed. */
RWUNLOCK(&dlz_implock, isc_rwlocktype_read);
isc_mem_put(mctx, (*dbp), sizeof(dns_dlzdb_t));
return (result);
}
void
dns_dlzdestroy(dns_dlzdb_t **dbp) {
isc_mem_t *mctx;
dns_dlzdestroy_t destroy;
/* Write debugging message to log */
isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE,
DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2),
"Unloading DLZ driver.");
/*
* Perform checks to make sure data is as we expect it to be.
*/
REQUIRE(dbp != NULL && DNS_DLZ_VALID(*dbp));
/* call the drivers destroy method */
if ((*dbp) != NULL) {
mctx = (*dbp)->mctx;
destroy = (*dbp)->implementation->methods->destroy;
(*destroy)((*dbp)->implementation->driverarg,(*dbp)->dbdata);
/* return memory */
isc_mem_put(mctx, (*dbp), sizeof(dns_dlzdb_t));
isc_mem_detach(&mctx);
}
*dbp = NULL;
}
isc_result_t
dns_dlzfindzone(dns_view_t *view, dns_name_t *name, unsigned int minlabels,
dns_db_t **dbp)
{
dns_fixedname_t fname;
dns_name_t *zonename;
unsigned int namelabels;
unsigned int i;
isc_result_t result;
dns_dlzfindzone_t findzone;
dns_dlzdb_t *dlzdatabase;
/*
* Performs checks to make sure data is as we expect it to be.
*/
REQUIRE(DNS_DLZ_VALID(view->dlzdatabase));
REQUIRE(name != NULL);
REQUIRE(dbp != NULL && *dbp == NULL);
/* setup a "fixed" dns name */
dns_fixedname_init(&fname);
zonename = dns_fixedname_name(&fname);
/* count the number of labels in the name */
namelabels = dns_name_countlabels(name);
/*
* loop through starting with the longest domain name and
* trying shorter names portions of the name until we find a
* match, have an error, or are below the 'minlabels'
* threshold. minlabels is 0, if the standard database didn't
* have a zone name match. Otherwise minlabels is the number
* of labels in that name. We need to beat that for a
* "better" match for the DLZ database to be authoritative
* instead of the standard database.
*/
for (i = namelabels; i > minlabels && i > 1; i--) {
if (i == namelabels) {
result = dns_name_copy(name, zonename, NULL);
if (result != ISC_R_SUCCESS)
return (result);
} else
dns_name_split(name, i, NULL, zonename);
/* ask SDLZ driver if the zone is supported */
dlzdatabase = view->dlzdatabase;
findzone = dlzdatabase->implementation->methods->findzone;
result = (*findzone)(dlzdatabase->implementation->driverarg,
dlzdatabase->dbdata, dlzdatabase->mctx,
view->rdclass, zonename, dbp);
if (result != ISC_R_NOTFOUND)
return (result);
}
return (ISC_R_NOTFOUND);
}
/*%
* Registers a DLZ driver. This basically just adds the dlz
* driver to the list of available drivers in the dlz_implementations list.
*/
isc_result_t
dns_dlzregister(const char *drivername, const dns_dlzmethods_t *methods,
void *driverarg, isc_mem_t *mctx,
dns_dlzimplementation_t **dlzimp)
{
dns_dlzimplementation_t *dlz_imp;
/* Write debugging message to log */
isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE,
DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2),
"Registering DLZ driver '%s'", drivername);
/*
* Performs checks to make sure data is as we expect it to be.
*/
REQUIRE(drivername != NULL);
REQUIRE(methods != NULL);
REQUIRE(methods->create != NULL);
REQUIRE(methods->destroy != NULL);
REQUIRE(methods->findzone != NULL);
REQUIRE(mctx != NULL);
REQUIRE(dlzimp != NULL && *dlzimp == NULL);
/*
* initialize the dlz_implementations list, this is guaranteed
* to only really happen once.
*/
RUNTIME_CHECK(isc_once_do(&once, dlz_initialize) == ISC_R_SUCCESS);
/* lock the dlz_implementations list so we can modify it. */
RWLOCK(&dlz_implock, isc_rwlocktype_write);
/*
* check that another already registered driver isn't using
* the same name
*/
dlz_imp = dlz_impfind(drivername);
if (dlz_imp != NULL) {
isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE,
DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2),
"DLZ Driver '%s' already registered",
drivername);
RWUNLOCK(&dlz_implock, isc_rwlocktype_write);
return (ISC_R_EXISTS);
}
/*
* Allocate memory for a dlz_implementation object. Error if
* we cannot.
*/
dlz_imp = isc_mem_get(mctx, sizeof(dns_dlzimplementation_t));
if (dlz_imp == NULL) {
RWUNLOCK(&dlz_implock, isc_rwlocktype_write);
return (ISC_R_NOMEMORY);
}
/* Make sure memory region is set to all 0's */
memset(dlz_imp, 0, sizeof(dns_dlzimplementation_t));
/* Store the data passed into this method */
dlz_imp->name = drivername;
dlz_imp->methods = methods;
dlz_imp->mctx = NULL;
dlz_imp->driverarg = driverarg;
/* attach the new dlz_implementation object to a memory context */
isc_mem_attach(mctx, &dlz_imp->mctx);
/*
* prepare the dlz_implementation object to be put in a list,
* and append it to the list
*/
ISC_LINK_INIT(dlz_imp, link);
ISC_LIST_APPEND(dlz_implementations, dlz_imp, link);
/* Unlock the dlz_implementations list. */
RWUNLOCK(&dlz_implock, isc_rwlocktype_write);
/* Pass back the dlz_implementation that we created. */
*dlzimp = dlz_imp;
return (ISC_R_SUCCESS);
}
/*%
* Helper function for dns_dlzstrtoargv().
* Pardon the gratuitous recursion.
*/
static isc_result_t
dns_dlzstrtoargvsub(isc_mem_t *mctx, char *s, unsigned int *argcp,
char ***argvp, unsigned int n)
{
isc_result_t result;
restart:
/* Discard leading whitespace. */
while (*s == ' ' || *s == '\t')
s++;
if (*s == '\0') {
/* We have reached the end of the string. */
*argcp = n;
*argvp = isc_mem_get(mctx, n * sizeof(char *));
if (*argvp == NULL)
return (ISC_R_NOMEMORY);
} else {
char *p = s;
while (*p != ' ' && *p != '\t' && *p != '\0' && *p != '{') {
if (*p == '\n') {
*p = ' ';
goto restart;
}
p++;
}
/* do "grouping", items between { and } are one arg */
if (*p == '{') {
char *t = p;
/*
* shift all characters to left by 1 to get rid of '{'
*/
while (*t != '\0') {
t++;
*(t-1) = *t;
}
while (*p != '\0' && *p != '}') {
p++;
}
/* get rid of '}' character */
if (*p == '}') {
*p = '\0';
p++;
}
/* normal case, no "grouping" */
} else if (*p != '\0')
*p++ = '\0';
result = dns_dlzstrtoargvsub(mctx, p, argcp, argvp, n + 1);
if (result != ISC_R_SUCCESS)
return (result);
(*argvp)[n] = s;
}
return (ISC_R_SUCCESS);
}
/*%
* Tokenize the string "s" into whitespace-separated words,
* return the number of words in '*argcp' and an array
* of pointers to the words in '*argvp'. The caller
* must free the array using isc_mem_put(). The string
* is modified in-place.
*/
isc_result_t
dns_dlzstrtoargv(isc_mem_t *mctx, char *s,
unsigned int *argcp, char ***argvp)
{
return(dns_dlzstrtoargvsub(mctx, s, argcp, argvp, 0));
}
/*%
* Unregisters a DLZ driver. This basically just removes the dlz
* driver from the list of available drivers in the dlz_implementations list.
*/
void
dns_dlzunregister(dns_dlzimplementation_t **dlzimp) {
dns_dlzimplementation_t *dlz_imp;
isc_mem_t *mctx;
/* Write debugging message to log */
isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE,
DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2),
"Unregistering DLZ driver.");
/*
* Performs checks to make sure data is as we expect it to be.
*/
REQUIRE(dlzimp != NULL && *dlzimp != NULL);
/*
* initialize the dlz_implementations list, this is guaranteed
* to only really happen once.
*/
RUNTIME_CHECK(isc_once_do(&once, dlz_initialize) == ISC_R_SUCCESS);
dlz_imp = *dlzimp;
/* lock the dlz_implementations list so we can modify it. */
RWLOCK(&dlz_implock, isc_rwlocktype_write);
/* remove the dlz_implementation object from the list */
ISC_LIST_UNLINK(dlz_implementations, dlz_imp, link);
mctx = dlz_imp->mctx;
/*
* return the memory back to the available memory pool and
* remove it from the memory context.
*/
isc_mem_put(mctx, dlz_imp, sizeof(dns_dlzimplementation_t));
isc_mem_detach(&mctx);
/* Unlock the dlz_implementations list. */
RWUNLOCK(&dlz_implock, isc_rwlocktype_write);
}