diff options
Diffstat (limited to 'contrib/bind9/lib/dns/rdataslab.c')
-rw-r--r-- | contrib/bind9/lib/dns/rdataslab.c | 715 |
1 files changed, 715 insertions, 0 deletions
diff --git a/contrib/bind9/lib/dns/rdataslab.c b/contrib/bind9/lib/dns/rdataslab.c new file mode 100644 index 000000000000..0604cd5d4d9b --- /dev/null +++ b/contrib/bind9/lib/dns/rdataslab.c @@ -0,0 +1,715 @@ +/* + * Copyright (C) 2004 Internet Systems Consortium, Inc. ("ISC") + * Copyright (C) 1999-2003 Internet Software Consortium. + * + * 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 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. + */ + +/* $Id: rdataslab.c,v 1.29.2.2.2.6 2004/03/08 09:04:31 marka Exp $ */ + +#include <config.h> + +#include <stdlib.h> + +#include <isc/mem.h> +#include <isc/region.h> +#include <isc/string.h> /* Required for HP/UX (and others?) */ +#include <isc/util.h> + +#include <dns/result.h> +#include <dns/rdata.h> +#include <dns/rdataset.h> +#include <dns/rdataslab.h> + +/* Note: the "const void *" are just to make qsort happy. */ +static int +compare_rdata(const void *p1, const void *p2) { + const dns_rdata_t *rdata1 = p1; + const dns_rdata_t *rdata2 = p2; + return (dns_rdata_compare(rdata1, rdata2)); +} + +isc_result_t +dns_rdataslab_fromrdataset(dns_rdataset_t *rdataset, isc_mem_t *mctx, + isc_region_t *region, unsigned int reservelen) +{ + dns_rdata_t *rdatas; + unsigned char *rawbuf; + unsigned int buflen; + isc_result_t result; + unsigned int nitems; + unsigned int nalloc; + unsigned int i; + + buflen = reservelen + 2; + + nalloc = dns_rdataset_count(rdataset); + nitems = nalloc; + if (nitems == 0) + return (ISC_R_FAILURE); + + rdatas = isc_mem_get(mctx, nalloc * sizeof(dns_rdata_t)); + if (rdatas == NULL) + return (ISC_R_NOMEMORY); + + /* + * Save all of the rdata members into an array. + */ + result = dns_rdataset_first(rdataset); + if (result != ISC_R_SUCCESS) + goto free_rdatas; + for (i = 0; i < nalloc && result == ISC_R_SUCCESS; i++) { + INSIST(result == ISC_R_SUCCESS); + dns_rdata_init(&rdatas[i]); + dns_rdataset_current(rdataset, &rdatas[i]); + result = dns_rdataset_next(rdataset); + } + if (result != ISC_R_NOMORE) + goto free_rdatas; + if (i != nalloc) { + /* + * Somehow we iterated over fewer rdatas than + * dns_rdataset_count() said there were! + */ + result = ISC_R_FAILURE; + goto free_rdatas; + } + + qsort(rdatas, nalloc, sizeof(dns_rdata_t), compare_rdata); + + /* + * Remove duplicates and compute the total storage required. + * + * If an rdata is not a duplicate, accumulate the storage size + * required for the rdata. We do not store the class, type, etc, + * just the rdata, so our overhead is 2 bytes for the number of + * records, and 2 for each rdata length, and then the rdata itself. + */ + for (i = 1; i < nalloc; i++) { + if (compare_rdata(&rdatas[i-1], &rdatas[i]) == 0) { + rdatas[i-1].data = NULL; + rdatas[i-1].length = 0; + nitems--; + } else + buflen += (2 + rdatas[i-1].length); + } + /* + * Don't forget the last item! + */ + buflen += (2 + rdatas[i-1].length); + + /* + * Ensure that singleton types are actually singletons. + */ + if (nitems > 1 && dns_rdatatype_issingleton(rdataset->type)) { + /* + * We have a singleton type, but there's more than one + * RR in the rdataset. + */ + result = DNS_R_SINGLETON; + goto free_rdatas; + } + + /* + * Allocate the memory, set up a buffer, start copying in + * data. + */ + rawbuf = isc_mem_get(mctx, buflen); + if (rawbuf == NULL) { + result = ISC_R_NOMEMORY; + goto free_rdatas; + } + + region->base = rawbuf; + region->length = buflen; + + rawbuf += reservelen; + + *rawbuf++ = (nitems & 0xff00) >> 8; + *rawbuf++ = (nitems & 0x00ff); + for (i = 0; i < nalloc; i++) { + if (rdatas[i].data == NULL) + continue; + *rawbuf++ = (rdatas[i].length & 0xff00) >> 8; + *rawbuf++ = (rdatas[i].length & 0x00ff); + memcpy(rawbuf, rdatas[i].data, rdatas[i].length); + rawbuf += rdatas[i].length; + } + result = ISC_R_SUCCESS; + + free_rdatas: + isc_mem_put(mctx, rdatas, nalloc * sizeof(dns_rdata_t)); + return (result); +} + +static void +rdataset_disassociate(dns_rdataset_t *rdataset) { + UNUSED(rdataset); +} + +static isc_result_t +rdataset_first(dns_rdataset_t *rdataset) { + unsigned char *raw = rdataset->private3; + unsigned int count; + + count = raw[0] * 256 + raw[1]; + if (count == 0) { + rdataset->private5 = NULL; + return (ISC_R_NOMORE); + } + raw += 2; + /* + * The privateuint4 field is the number of rdata beyond the cursor + * position, so we decrement the total count by one before storing + * it. + */ + count--; + rdataset->privateuint4 = count; + rdataset->private5 = raw; + + return (ISC_R_SUCCESS); +} + +static isc_result_t +rdataset_next(dns_rdataset_t *rdataset) { + unsigned int count; + unsigned int length; + unsigned char *raw; + + count = rdataset->privateuint4; + if (count == 0) + return (ISC_R_NOMORE); + count--; + rdataset->privateuint4 = count; + raw = rdataset->private5; + length = raw[0] * 256 + raw[1]; + raw += length + 2; + rdataset->private5 = raw; + + return (ISC_R_SUCCESS); +} + +static void +rdataset_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata) { + unsigned char *raw = rdataset->private5; + isc_region_t r; + + REQUIRE(raw != NULL); + + r.length = raw[0] * 256 + raw[1]; + raw += 2; + r.base = raw; + dns_rdata_fromregion(rdata, rdataset->rdclass, rdataset->type, &r); +} + +static void +rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target) { + *target = *source; + + /* + * Reset iterator state. + */ + target->privateuint4 = 0; + target->private5 = NULL; +} + +static unsigned int +rdataset_count(dns_rdataset_t *rdataset) { + unsigned char *raw = rdataset->private3; + unsigned int count; + + count = raw[0] * 256 + raw[1]; + + return (count); +} + +static dns_rdatasetmethods_t rdataset_methods = { + rdataset_disassociate, + rdataset_first, + rdataset_next, + rdataset_current, + rdataset_clone, + rdataset_count, + NULL, + NULL +}; + +void +dns_rdataslab_tordataset(unsigned char *slab, unsigned int reservelen, + dns_rdataclass_t rdclass, dns_rdatatype_t rdtype, + dns_rdatatype_t covers, dns_ttl_t ttl, + dns_rdataset_t *rdataset) +{ + REQUIRE(slab != NULL); + REQUIRE(!dns_rdataset_isassociated(rdataset)); + + rdataset->methods = &rdataset_methods; + rdataset->rdclass = rdclass; + rdataset->type = rdtype; + rdataset->covers = covers; + rdataset->ttl = ttl; + rdataset->trust = 0; + rdataset->private1 = NULL; + rdataset->private2 = NULL; + rdataset->private3 = slab + reservelen; + + /* + * Reset iterator state. + */ + rdataset->privateuint4 = 0; + rdataset->private5 = NULL; +} + +unsigned int +dns_rdataslab_size(unsigned char *slab, unsigned int reservelen) { + unsigned int count, length; + unsigned char *current; + + REQUIRE(slab != NULL); + + current = slab + reservelen; + count = *current++ * 256; + count += *current++; + while (count > 0) { + count--; + length = *current++ * 256; + length += *current++; + current += length; + } + + return ((unsigned int)(current - slab)); +} + +/* + * Make the dns_rdata_t 'rdata' refer to the slab item + * beginning at '*current', which is part of a slab of type + * 'type' and class 'rdclass', and advance '*current' to + * point to the next item in the slab. + */ +static inline void +rdata_from_slab(unsigned char **current, + dns_rdataclass_t rdclass, dns_rdatatype_t type, + dns_rdata_t *rdata) +{ + unsigned char *tcurrent = *current; + isc_region_t region; + + region.length = *tcurrent++ * 256; + region.length += *tcurrent++; + region.base = tcurrent; + tcurrent += region.length; + dns_rdata_fromregion(rdata, rdclass, type, ®ion); + *current = tcurrent; +} + +/* + * Return true iff 'slab' (slab data of type 'type' and class 'rdclass') + * contains an rdata identical to 'rdata'. This does case insensitive + * comparisons per DNSSEC. + */ +static inline isc_boolean_t +rdata_in_slab(unsigned char *slab, unsigned int reservelen, + dns_rdataclass_t rdclass, dns_rdatatype_t type, + dns_rdata_t *rdata) +{ + unsigned int count, i; + unsigned char *current; + dns_rdata_t trdata = DNS_RDATA_INIT; + + current = slab + reservelen; + count = *current++ * 256; + count += *current++; + + for (i = 0; i < count; i++) { + rdata_from_slab(¤t, rdclass, type, &trdata); + if (dns_rdata_compare(&trdata, rdata) == 0) + return (ISC_TRUE); + dns_rdata_reset(&trdata); + } + return (ISC_FALSE); +} + +isc_result_t +dns_rdataslab_merge(unsigned char *oslab, unsigned char *nslab, + unsigned int reservelen, isc_mem_t *mctx, + dns_rdataclass_t rdclass, dns_rdatatype_t type, + unsigned int flags, unsigned char **tslabp) +{ + unsigned char *ocurrent, *ostart, *ncurrent, *tstart, *tcurrent; + unsigned int ocount, ncount, count, olength, tlength, tcount, length; + isc_region_t nregion; + dns_rdata_t ordata = DNS_RDATA_INIT; + dns_rdata_t nrdata = DNS_RDATA_INIT; + isc_boolean_t added_something = ISC_FALSE; + unsigned int oadded = 0; + unsigned int nadded = 0; + unsigned int nncount = 0; + + /* + * XXX Need parameter to allow "delete rdatasets in nslab" merge, + * or perhaps another merge routine for this purpose. + */ + + REQUIRE(tslabp != NULL && *tslabp == NULL); + REQUIRE(oslab != NULL && nslab != NULL); + + ocurrent = oslab + reservelen; + ocount = *ocurrent++ * 256; + ocount += *ocurrent++; + ostart = ocurrent; + ncurrent = nslab + reservelen; + ncount = *ncurrent++ * 256; + ncount += *ncurrent++; + INSIST(ocount > 0 && ncount > 0); + + /* + * Yes, this is inefficient! + */ + + /* + * Figure out the length of the old slab's data. + */ + olength = 0; + for (count = 0; count < ocount; count++) { + length = *ocurrent++ * 256; + length += *ocurrent++; + olength += length + 2; + ocurrent += length; + } + + /* + * Start figuring out the target length and count. + */ + tlength = reservelen + 2 + olength; + tcount = ocount; + + /* + * Add in the length of rdata in the new slab that aren't in + * the old slab. + */ + do { + nregion.length = *ncurrent++ * 256; + nregion.length += *ncurrent++; + nregion.base = ncurrent; + dns_rdata_init(&nrdata); + dns_rdata_fromregion(&nrdata, rdclass, type, &nregion); + if (!rdata_in_slab(oslab, reservelen, rdclass, type, &nrdata)) + { + /* + * This rdata isn't in the old slab. + */ + tlength += nregion.length + 2; + tcount++; + nncount++; + added_something = ISC_TRUE; + } + ncurrent += nregion.length; + ncount--; + } while (ncount > 0); + ncount = nncount; + + if (((flags & DNS_RDATASLAB_EXACT) != 0) && + (tcount != ncount + ocount)) + return (DNS_R_NOTEXACT); + + if (!added_something && (flags & DNS_RDATASLAB_FORCE) == 0) + return (DNS_R_UNCHANGED); + + /* + * Ensure that singleton types are actually singletons. + */ + if (tcount > 1 && dns_rdatatype_issingleton(type)) { + /* + * We have a singleton type, but there's more than one + * RR in the rdataset. + */ + return (DNS_R_SINGLETON); + } + + /* + * Copy the reserved area from the new slab. + */ + tstart = isc_mem_get(mctx, tlength); + if (tstart == NULL) + return (ISC_R_NOMEMORY); + memcpy(tstart, nslab, reservelen); + tcurrent = tstart + reservelen; + + /* + * Write the new count. + */ + *tcurrent++ = (tcount & 0xff00) >> 8; + *tcurrent++ = (tcount & 0x00ff); + + /* + * Merge the two slabs. + */ + ocurrent = ostart; + INSIST(ocount != 0); + rdata_from_slab(&ocurrent, rdclass, type, &ordata); + + ncurrent = nslab + reservelen + 2; + if (ncount > 0) { + do { + dns_rdata_reset(&nrdata); + rdata_from_slab(&ncurrent, rdclass, type, &nrdata); + } while (rdata_in_slab(oslab, reservelen, rdclass, + type, &nrdata)); + } + + while (oadded < ocount || nadded < ncount) { + isc_boolean_t fromold; + if (oadded == ocount) + fromold = ISC_FALSE; + else if (nadded == ncount) + fromold = ISC_TRUE; + else + fromold = ISC_TF(compare_rdata(&ordata, &nrdata) < 0); + if (fromold) { + length = ordata.length; + *tcurrent++ = (length & 0xff00) >> 8; + *tcurrent++ = (length & 0x00ff); + memcpy(tcurrent, ordata.data, length); + tcurrent += length; + oadded++; + if (oadded < ocount) { + dns_rdata_reset(&ordata); + rdata_from_slab(&ocurrent, rdclass, type, + &ordata); + } + } else { + length = nrdata.length; + *tcurrent++ = (length & 0xff00) >> 8; + *tcurrent++ = (length & 0x00ff); + memcpy(tcurrent, nrdata.data, length); + tcurrent += length; + nadded++; + if (nadded < ncount) { + do { + dns_rdata_reset(&nrdata); + rdata_from_slab(&ncurrent, rdclass, + type, &nrdata); + } while (rdata_in_slab(oslab, reservelen, + rdclass, type, + &nrdata)); + } + } + } + + INSIST(tcurrent == tstart + tlength); + + *tslabp = tstart; + + return (ISC_R_SUCCESS); +} + +isc_result_t +dns_rdataslab_subtract(unsigned char *mslab, unsigned char *sslab, + unsigned int reservelen, isc_mem_t *mctx, + dns_rdataclass_t rdclass, dns_rdatatype_t type, + unsigned int flags, unsigned char **tslabp) +{ + unsigned char *mcurrent, *sstart, *scurrent, *tstart, *tcurrent; + unsigned int mcount, scount, rcount ,count, tlength, tcount; + dns_rdata_t srdata = DNS_RDATA_INIT; + dns_rdata_t mrdata = DNS_RDATA_INIT; + + REQUIRE(tslabp != NULL && *tslabp == NULL); + REQUIRE(mslab != NULL && sslab != NULL); + + mcurrent = mslab + reservelen; + mcount = *mcurrent++ * 256; + mcount += *mcurrent++; + scurrent = sslab + reservelen; + scount = *scurrent++ * 256; + scount += *scurrent++; + sstart = scurrent; + INSIST(mcount > 0 && scount > 0); + + /* + * Yes, this is inefficient! + */ + + /* + * Start figuring out the target length and count. + */ + tlength = reservelen + 2; + tcount = 0; + rcount = 0; + + /* + * Add in the length of rdata in the mslab that aren't in + * the sslab. + */ + do { + unsigned char *mrdatabegin = mcurrent; + rdata_from_slab(&mcurrent, rdclass, type, &mrdata); + scurrent = sstart; + for (count = 0; count < scount; count++) { + dns_rdata_reset(&srdata); + rdata_from_slab(&scurrent, rdclass, type, &srdata); + if (dns_rdata_compare(&mrdata, &srdata) == 0) + break; + } + if (count == scount) { + /* + * This rdata isn't in the sslab, and thus isn't + * being subtracted. + */ + tlength += mcurrent - mrdatabegin; + tcount++; + } else + rcount++; + mcount--; + dns_rdata_reset(&mrdata); + } while (mcount > 0); + + /* + * Check that all the records originally existed. The numeric + * check only works as rdataslabs do not contain duplicates. + */ + if (((flags & DNS_RDATASLAB_EXACT) != 0) && (rcount != scount)) + return (DNS_R_NOTEXACT); + + /* + * Don't continue if the new rdataslab would be empty. + */ + if (tcount == 0) + return (DNS_R_NXRRSET); + + /* + * If nothing is going to change, we can stop. + */ + if (rcount == 0) + return (DNS_R_UNCHANGED); + + /* + * Copy the reserved area from the mslab. + */ + tstart = isc_mem_get(mctx, tlength); + if (tstart == NULL) + return (ISC_R_NOMEMORY); + memcpy(tstart, mslab, reservelen); + tcurrent = tstart + reservelen; + + /* + * Write the new count. + */ + *tcurrent++ = (tcount & 0xff00) >> 8; + *tcurrent++ = (tcount & 0x00ff); + + /* + * Copy the parts of mslab not in sslab. + */ + mcurrent = mslab + reservelen; + mcount = *mcurrent++ * 256; + mcount += *mcurrent++; + do { + unsigned char *mrdatabegin = mcurrent; + rdata_from_slab(&mcurrent, rdclass, type, &mrdata); + scurrent = sstart; + for (count = 0; count < scount; count++) { + dns_rdata_reset(&srdata); + rdata_from_slab(&scurrent, rdclass, type, &srdata); + if (dns_rdata_compare(&mrdata, &srdata) == 0) + break; + } + if (count == scount) { + /* + * This rdata isn't in the sslab, and thus should be + * copied to the tslab. + */ + unsigned int length = mcurrent - mrdatabegin; + memcpy(tcurrent, mrdatabegin, length); + tcurrent += length; + } + dns_rdata_reset(&mrdata); + mcount--; + } while (mcount > 0); + + INSIST(tcurrent == tstart + tlength); + + *tslabp = tstart; + + return (ISC_R_SUCCESS); +} + +isc_boolean_t +dns_rdataslab_equal(unsigned char *slab1, unsigned char *slab2, + unsigned int reservelen) +{ + unsigned char *current1, *current2; + unsigned int count1, count2; + unsigned int length1, length2; + + current1 = slab1 + reservelen; + count1 = *current1++ * 256; + count1 += *current1++; + + current2 = slab2 + reservelen; + count2 = *current2++ * 256; + count2 += *current2++; + + if (count1 != count2) + return (ISC_FALSE); + + while (count1 > 0) { + length1 = *current1++ * 256; + length1 += *current1++; + + length2 = *current2++ * 256; + length2 += *current2++; + + if (length1 != length2 || + memcmp(current1, current2, length1) != 0) + return (ISC_FALSE); + + current1 += length1; + current2 += length1; + + count1--; + } + return (ISC_TRUE); +} + +isc_boolean_t +dns_rdataslab_equalx(unsigned char *slab1, unsigned char *slab2, + unsigned int reservelen, dns_rdataclass_t rdclass, + dns_rdatatype_t type) +{ + unsigned char *current1, *current2; + unsigned int count1, count2; + dns_rdata_t rdata1 = DNS_RDATA_INIT; + dns_rdata_t rdata2 = DNS_RDATA_INIT; + + current1 = slab1 + reservelen; + count1 = *current1++ * 256; + count1 += *current1++; + + current2 = slab2 + reservelen; + count2 = *current2++ * 256; + count2 += *current2++; + + if (count1 != count2) + return (ISC_FALSE); + + while (count1-- > 0) { + rdata_from_slab(¤t1, rdclass, type, &rdata1); + rdata_from_slab(¤t2, rdclass, type, &rdata2); + if (dns_rdata_compare(&rdata1, &rdata2) != 0) + return (ISC_FALSE); + dns_rdata_reset(&rdata1); + dns_rdata_reset(&rdata2); + } + return (ISC_TRUE); +} |