/* $NetBSD: rdataslab.c,v 1.6.2.2 2024/02/25 15:46:52 martin Exp $ */ /* * Copyright (C) Internet Systems Consortium, Inc. ("ISC") * * SPDX-License-Identifier: MPL-2.0 * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, you can obtain one at https://mozilla.org/MPL/2.0/. * * See the COPYRIGHT file distributed with this work for additional * information regarding copyright ownership. */ /*! \file */ #include #include #include #include #include #include /* Required for HP/UX (and others?) */ #include #include #include #include /* * The rdataslab structure allows iteration to occur in both load order * and DNSSEC order. The structure is as follows: * * header (reservelen bytes) * record count (2 bytes) * offset table (4 x record count bytes in load order) * data records * data length (2 bytes) * order (2 bytes) * meta data (1 byte for RRSIG's) * data (data length bytes) * * If DNS_RDATASET_FIXED is defined to be zero (0) the format of a * rdataslab is as follows: * * header (reservelen bytes) * record count (2 bytes) * data records * data length (2 bytes) * meta data (1 byte for RRSIG's) * data (data length bytes) * * Offsets are from the end of the header. * * Load order traversal is performed by walking the offset table to find * the start of the record (DNS_RDATASET_FIXED = 1). * * DNSSEC order traversal is performed by walking the data records. * * The order is stored with record to allow for efficient reconstruction * of the offset table following a merge or subtraction. * * The iterator methods in rbtdb support both load order and DNSSEC order * iteration. * * WARNING: * rbtdb.c directly interacts with the slab's raw structures. If the * structure changes then rbtdb.c also needs to be updated to reflect * the changes. See the areas tagged with "RDATASLAB". */ struct xrdata { dns_rdata_t rdata; unsigned int order; }; /*% Note: the "const void *" are just to make qsort happy. */ static int compare_rdata(const void *p1, const void *p2) { const struct xrdata *x1 = p1; const struct xrdata *x2 = p2; return (dns_rdata_compare(&x1->rdata, &x2->rdata)); } #if DNS_RDATASET_FIXED static void fillin_offsets(unsigned char *offsetbase, unsigned int *offsettable, unsigned length) { unsigned int i, j; unsigned char *raw; for (i = 0, j = 0; i < length; i++) { if (offsettable[i] == 0) { continue; } /* * Fill in offset table. */ raw = &offsetbase[j * 4 + 2]; *raw++ = (offsettable[i] & 0xff000000) >> 24; *raw++ = (offsettable[i] & 0xff0000) >> 16; *raw++ = (offsettable[i] & 0xff00) >> 8; *raw = offsettable[i] & 0xff; /* * Fill in table index. */ raw = offsetbase + offsettable[i] + 2; *raw++ = (j & 0xff00) >> 8; *raw = j++ & 0xff; } } #endif /* if DNS_RDATASET_FIXED */ isc_result_t dns_rdataslab_fromrdataset(dns_rdataset_t *rdataset, isc_mem_t *mctx, isc_region_t *region, unsigned int reservelen) { /* * Use &removed as a sentinel pointer for duplicate * rdata as rdata.data == NULL is valid. */ static unsigned char removed; struct xrdata *x; unsigned char *rawbuf; #if DNS_RDATASET_FIXED unsigned char *offsetbase; #endif /* if DNS_RDATASET_FIXED */ unsigned int buflen; isc_result_t result; unsigned int nitems; unsigned int nalloc; unsigned int i; #if DNS_RDATASET_FIXED unsigned int *offsettable; #endif /* if DNS_RDATASET_FIXED */ unsigned int length; buflen = reservelen + 2; nitems = dns_rdataset_count(rdataset); /* * If there are no rdata then we can just need to allocate a header * with zero a record count. */ if (nitems == 0) { if (rdataset->type != 0) { return (ISC_R_FAILURE); } rawbuf = isc_mem_get(mctx, buflen); region->base = rawbuf; region->length = buflen; rawbuf += reservelen; *rawbuf++ = 0; *rawbuf = 0; return (ISC_R_SUCCESS); } if (nitems > 0xffff) { return (ISC_R_NOSPACE); } /* * Remember the original number of items. */ nalloc = nitems; x = isc_mem_get(mctx, nalloc * sizeof(struct xrdata)); /* * Save all of the rdata members into an array. */ result = dns_rdataset_first(rdataset); if (result != ISC_R_SUCCESS && result != ISC_R_NOMORE) { goto free_rdatas; } for (i = 0; i < nalloc && result == ISC_R_SUCCESS; i++) { INSIST(result == ISC_R_SUCCESS); dns_rdata_init(&x[i].rdata); dns_rdataset_current(rdataset, &x[i].rdata); INSIST(x[i].rdata.data != &removed); #if DNS_RDATASET_FIXED x[i].order = i; #endif /* if DNS_RDATASET_FIXED */ result = dns_rdataset_next(rdataset); } if (i != nalloc || result != ISC_R_NOMORE) { /* * Somehow we iterated over fewer rdatas than * dns_rdataset_count() said there were or there * were more items than dns_rdataset_count said * there were. */ result = ISC_R_FAILURE; goto free_rdatas; } /* * Put into DNSSEC order. */ if (nalloc > 1U) { qsort(x, nalloc, sizeof(struct xrdata), 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 8 for each rdata, (length(2), offset(4) and order(2)) * and then the rdata itself. */ for (i = 1; i < nalloc; i++) { if (compare_rdata(&x[i - 1].rdata, &x[i].rdata) == 0) { x[i - 1].rdata.data = &removed; #if DNS_RDATASET_FIXED /* * Preserve the least order so A, B, A -> A, B * after duplicate removal. */ if (x[i - 1].order < x[i].order) { x[i].order = x[i - 1].order; } #endif /* if DNS_RDATASET_FIXED */ nitems--; } else { #if DNS_RDATASET_FIXED buflen += (8 + x[i - 1].rdata.length); #else /* if DNS_RDATASET_FIXED */ buflen += (2 + x[i - 1].rdata.length); #endif /* if DNS_RDATASET_FIXED */ /* * Provide space to store the per RR meta data. */ if (rdataset->type == dns_rdatatype_rrsig) { buflen++; } } } /* * Don't forget the last item! */ #if DNS_RDATASET_FIXED buflen += (8 + x[i - 1].rdata.length); #else /* if DNS_RDATASET_FIXED */ buflen += (2 + x[i - 1].rdata.length); #endif /* if DNS_RDATASET_FIXED */ /* * Provide space to store the per RR meta data. */ if (rdataset->type == dns_rdatatype_rrsig) { buflen++; } /* * 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 DNS_RDATASET_FIXED /* Allocate temporary offset table. */ offsettable = isc_mem_get(mctx, nalloc * sizeof(unsigned int)); memset(offsettable, 0, nalloc * sizeof(unsigned int)); #endif /* if DNS_RDATASET_FIXED */ region->base = rawbuf; region->length = buflen; memset(rawbuf, 0, buflen); rawbuf += reservelen; #if DNS_RDATASET_FIXED offsetbase = rawbuf; #endif /* if DNS_RDATASET_FIXED */ *rawbuf++ = (nitems & 0xff00) >> 8; *rawbuf++ = (nitems & 0x00ff); #if DNS_RDATASET_FIXED /* Skip load order table. Filled in later. */ rawbuf += nitems * 4; #endif /* if DNS_RDATASET_FIXED */ for (i = 0; i < nalloc; i++) { if (x[i].rdata.data == &removed) { continue; } #if DNS_RDATASET_FIXED offsettable[x[i].order] = rawbuf - offsetbase; #endif /* if DNS_RDATASET_FIXED */ length = x[i].rdata.length; if (rdataset->type == dns_rdatatype_rrsig) { length++; } INSIST(length <= 0xffff); *rawbuf++ = (length & 0xff00) >> 8; *rawbuf++ = (length & 0x00ff); #if DNS_RDATASET_FIXED rawbuf += 2; /* filled in later */ #endif /* if DNS_RDATASET_FIXED */ /* * Store the per RR meta data. */ if (rdataset->type == dns_rdatatype_rrsig) { *rawbuf++ = (x[i].rdata.flags & DNS_RDATA_OFFLINE) ? DNS_RDATASLAB_OFFLINE : 0; } memmove(rawbuf, x[i].rdata.data, x[i].rdata.length); rawbuf += x[i].rdata.length; } #if DNS_RDATASET_FIXED fillin_offsets(offsetbase, offsettable, nalloc); isc_mem_put(mctx, offsettable, nalloc * sizeof(unsigned int)); #endif /* if DNS_RDATASET_FIXED */ result = ISC_R_SUCCESS; free_rdatas: isc_mem_put(mctx, x, nalloc * sizeof(struct xrdata)); return (result); } 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++; #if DNS_RDATASET_FIXED current += (4 * count); #endif /* if DNS_RDATASET_FIXED */ while (count > 0) { count--; length = *current++ * 256; length += *current++; #if DNS_RDATASET_FIXED current += length + 2; #else /* if DNS_RDATASET_FIXED */ current += length; #endif /* if DNS_RDATASET_FIXED */ } return ((unsigned int)(current - slab)); } unsigned int dns_rdataslab_rdatasize(unsigned char *slab, unsigned int reservelen) { unsigned int count, length, rdatalen = 0; unsigned char *current; REQUIRE(slab != NULL); current = slab + reservelen; count = *current++ * 256; count += *current++; #if DNS_RDATASET_FIXED current += (4 * count); #endif /* if DNS_RDATASET_FIXED */ while (count > 0) { count--; length = *current++ * 256; length += *current++; rdatalen += length; #if DNS_RDATASET_FIXED current += length + 2; #else /* if DNS_RDATASET_FIXED */ current += length; #endif /* if DNS_RDATASET_FIXED */ } return (rdatalen); } unsigned int dns_rdataslab_count(unsigned char *slab, unsigned int reservelen) { unsigned int count; unsigned char *current; REQUIRE(slab != NULL); current = slab + reservelen; count = *current++ * 256; count += *current++; return (count); } /* * 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 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; unsigned int length; bool offline = false; length = *tcurrent++ * 256; length += *tcurrent++; if (type == dns_rdatatype_rrsig) { if ((*tcurrent & DNS_RDATASLAB_OFFLINE) != 0) { offline = true; } length--; tcurrent++; } region.length = length; #if DNS_RDATASET_FIXED tcurrent += 2; #endif /* if DNS_RDATASET_FIXED */ region.base = tcurrent; tcurrent += region.length; dns_rdata_fromregion(rdata, rdclass, type, ®ion); if (offline) { rdata->flags |= DNS_RDATA_OFFLINE; } *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 bool 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; int n; current = slab + reservelen; count = *current++ * 256; count += *current++; #if DNS_RDATASET_FIXED current += (4 * count); #endif /* if DNS_RDATASET_FIXED */ for (i = 0; i < count; i++) { rdata_from_slab(¤t, rdclass, type, &trdata); n = dns_rdata_compare(&trdata, rdata); if (n == 0) { return (true); } if (n > 0) { /* In DNSSEC order. */ break; } dns_rdata_reset(&trdata); } return (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, *data; unsigned int ocount, ncount, count, olength, tlength, tcount, length; dns_rdata_t ordata = DNS_RDATA_INIT; dns_rdata_t nrdata = DNS_RDATA_INIT; bool added_something = false; unsigned int oadded = 0; unsigned int nadded = 0; unsigned int nncount = 0; #if DNS_RDATASET_FIXED unsigned int oncount; unsigned int norder = 0; unsigned int oorder = 0; unsigned char *offsetbase; unsigned int *offsettable; #endif /* if DNS_RDATASET_FIXED */ /* * 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++; #if DNS_RDATASET_FIXED ocurrent += (4 * ocount); #endif /* if DNS_RDATASET_FIXED */ ostart = ocurrent; ncurrent = nslab + reservelen; ncount = *ncurrent++ * 256; ncount += *ncurrent++; #if DNS_RDATASET_FIXED ncurrent += (4 * ncount); #endif /* if DNS_RDATASET_FIXED */ INSIST(ocount > 0 && ncount > 0); #if DNS_RDATASET_FIXED oncount = ncount; #endif /* if DNS_RDATASET_FIXED */ /* * 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++; #if DNS_RDATASET_FIXED olength += length + 8; ocurrent += length + 2; #else /* if DNS_RDATASET_FIXED */ olength += length + 2; ocurrent += length; #endif /* if DNS_RDATASET_FIXED */ } /* * 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 { dns_rdata_init(&nrdata); rdata_from_slab(&ncurrent, rdclass, type, &nrdata); if (!rdata_in_slab(oslab, reservelen, rdclass, type, &nrdata)) { /* * This rdata isn't in the old slab. */ #if DNS_RDATASET_FIXED tlength += nrdata.length + 8; #else /* if DNS_RDATASET_FIXED */ tlength += nrdata.length + 2; #endif /* if DNS_RDATASET_FIXED */ if (type == dns_rdatatype_rrsig) { tlength++; } tcount++; nncount++; added_something = true; } 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); } if (tcount > 0xffff) { return (ISC_R_NOSPACE); } /* * Copy the reserved area from the new slab. */ tstart = isc_mem_get(mctx, tlength); memmove(tstart, nslab, reservelen); tcurrent = tstart + reservelen; #if DNS_RDATASET_FIXED offsetbase = tcurrent; #endif /* if DNS_RDATASET_FIXED */ /* * Write the new count. */ *tcurrent++ = (tcount & 0xff00) >> 8; *tcurrent++ = (tcount & 0x00ff); #if DNS_RDATASET_FIXED /* * Skip offset table. */ tcurrent += (tcount * 4); offsettable = isc_mem_get(mctx, (ocount + oncount) * sizeof(unsigned int)); memset(offsettable, 0, (ocount + oncount) * sizeof(unsigned int)); #endif /* if DNS_RDATASET_FIXED */ /* * Merge the two slabs. */ ocurrent = ostart; INSIST(ocount != 0); #if DNS_RDATASET_FIXED oorder = ocurrent[2] * 256 + ocurrent[3]; INSIST(oorder < ocount); #endif /* if DNS_RDATASET_FIXED */ rdata_from_slab(&ocurrent, rdclass, type, &ordata); ncurrent = nslab + reservelen + 2; #if DNS_RDATASET_FIXED ncurrent += (4 * oncount); #endif /* if DNS_RDATASET_FIXED */ if (ncount > 0) { do { dns_rdata_reset(&nrdata); #if DNS_RDATASET_FIXED norder = ncurrent[2] * 256 + ncurrent[3]; INSIST(norder < oncount); #endif /* if DNS_RDATASET_FIXED */ rdata_from_slab(&ncurrent, rdclass, type, &nrdata); } while (rdata_in_slab(oslab, reservelen, rdclass, type, &nrdata)); } while (oadded < ocount || nadded < ncount) { bool fromold; if (oadded == ocount) { fromold = false; } else if (nadded == ncount) { fromold = true; } else { fromold = (dns_rdata_compare(&ordata, &nrdata) < 0); } if (fromold) { #if DNS_RDATASET_FIXED offsettable[oorder] = tcurrent - offsetbase; #endif /* if DNS_RDATASET_FIXED */ length = ordata.length; data = ordata.data; if (type == dns_rdatatype_rrsig) { length++; data--; } *tcurrent++ = (length & 0xff00) >> 8; *tcurrent++ = (length & 0x00ff); #if DNS_RDATASET_FIXED tcurrent += 2; /* fill in later */ #endif /* if DNS_RDATASET_FIXED */ memmove(tcurrent, data, length); tcurrent += length; oadded++; if (oadded < ocount) { dns_rdata_reset(&ordata); #if DNS_RDATASET_FIXED oorder = ocurrent[2] * 256 + ocurrent[3]; INSIST(oorder < ocount); #endif /* if DNS_RDATASET_FIXED */ rdata_from_slab(&ocurrent, rdclass, type, &ordata); } } else { #if DNS_RDATASET_FIXED offsettable[ocount + norder] = tcurrent - offsetbase; #endif /* if DNS_RDATASET_FIXED */ length = nrdata.length; data = nrdata.data; if (type == dns_rdatatype_rrsig) { length++; data--; } *tcurrent++ = (length & 0xff00) >> 8; *tcurrent++ = (length & 0x00ff); #if DNS_RDATASET_FIXED tcurrent += 2; /* fill in later */ #endif /* if DNS_RDATASET_FIXED */ memmove(tcurrent, data, length); tcurrent += length; nadded++; if (nadded < ncount) { do { dns_rdata_reset(&nrdata); #if DNS_RDATASET_FIXED norder = ncurrent[2] * 256 + ncurrent[3]; INSIST(norder < oncount); #endif /* if DNS_RDATASET_FIXED */ rdata_from_slab(&ncurrent, rdclass, type, &nrdata); } while (rdata_in_slab(oslab, reservelen, rdclass, type, &nrdata)); } } } #if DNS_RDATASET_FIXED fillin_offsets(offsetbase, offsettable, ocount + oncount); isc_mem_put(mctx, offsettable, (ocount + oncount) * sizeof(unsigned int)); #endif /* if DNS_RDATASET_FIXED */ 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, i; dns_rdata_t srdata = DNS_RDATA_INIT; dns_rdata_t mrdata = DNS_RDATA_INIT; #if DNS_RDATASET_FIXED unsigned char *offsetbase; unsigned int *offsettable; unsigned int order; #endif /* if DNS_RDATASET_FIXED */ 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++; INSIST(mcount > 0 && scount > 0); /* * Yes, this is inefficient! */ /* * Start figuring out the target length and count. */ tlength = reservelen + 2; tcount = 0; rcount = 0; #if DNS_RDATASET_FIXED mcurrent += 4 * mcount; scurrent += 4 * scount; #endif /* if DNS_RDATASET_FIXED */ sstart = scurrent; /* * Add in the length of rdata in the mslab that aren't in * the sslab. */ for (i = 0; i < mcount; i++) { 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 += (unsigned int)(mcurrent - mrdatabegin); tcount++; } else { rcount++; } dns_rdata_reset(&mrdata); } #if DNS_RDATASET_FIXED tlength += (4 * tcount); #endif /* if DNS_RDATASET_FIXED */ /* * 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); memmove(tstart, mslab, reservelen); tcurrent = tstart + reservelen; #if DNS_RDATASET_FIXED offsetbase = tcurrent; offsettable = isc_mem_get(mctx, mcount * sizeof(unsigned int)); memset(offsettable, 0, mcount * sizeof(unsigned int)); #endif /* if DNS_RDATASET_FIXED */ /* * Write the new count. */ *tcurrent++ = (tcount & 0xff00) >> 8; *tcurrent++ = (tcount & 0x00ff); #if DNS_RDATASET_FIXED tcurrent += (4 * tcount); #endif /* if DNS_RDATASET_FIXED */ /* * Copy the parts of mslab not in sslab. */ mcurrent = mslab + reservelen; mcount = *mcurrent++ * 256; mcount += *mcurrent++; #if DNS_RDATASET_FIXED mcurrent += (4 * mcount); #endif /* if DNS_RDATASET_FIXED */ for (i = 0; i < mcount; i++) { unsigned char *mrdatabegin = mcurrent; #if DNS_RDATASET_FIXED order = mcurrent[2] * 256 + mcurrent[3]; INSIST(order < mcount); #endif /* if DNS_RDATASET_FIXED */ 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; length = (unsigned int)(mcurrent - mrdatabegin); #if DNS_RDATASET_FIXED offsettable[order] = tcurrent - offsetbase; #endif /* if DNS_RDATASET_FIXED */ memmove(tcurrent, mrdatabegin, length); tcurrent += length; } dns_rdata_reset(&mrdata); } #if DNS_RDATASET_FIXED fillin_offsets(offsetbase, offsettable, mcount); isc_mem_put(mctx, offsettable, mcount * sizeof(unsigned int)); #endif /* if DNS_RDATASET_FIXED */ INSIST(tcurrent == tstart + tlength); *tslabp = tstart; return (ISC_R_SUCCESS); } bool 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 (false); } #if DNS_RDATASET_FIXED current1 += (4 * count1); current2 += (4 * count2); #endif /* if DNS_RDATASET_FIXED */ while (count1 > 0) { length1 = *current1++ * 256; length1 += *current1++; length2 = *current2++ * 256; length2 += *current2++; #if DNS_RDATASET_FIXED current1 += 2; current2 += 2; #endif /* if DNS_RDATASET_FIXED */ if (length1 != length2 || memcmp(current1, current2, length1) != 0) { return (false); } current1 += length1; current2 += length1; count1--; } return (true); } bool 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 (false); } #if DNS_RDATASET_FIXED current1 += (4 * count1); current2 += (4 * count2); #endif /* if DNS_RDATASET_FIXED */ 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 (false); } dns_rdata_reset(&rdata1); dns_rdata_reset(&rdata2); } return (true); }