/* * 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. */ #pragma once /*! \file dns/rdataslab.h * \brief * Implements storage of rdatasets into slabs of memory. * * MP: *\li Clients of this module must impose any required synchronization. * * Reliability: *\li This module deals with low-level byte streams. Errors in any of * the functions are likely to crash the server or corrupt memory. * *\li If the caller passes invalid memory references, these functions are * likely to crash the server or corrupt memory. * * Resources: *\li None. * * Security: *\li None. * * Standards: *\li None. */ /*** *** Imports ***/ #include #include #include #include #include #include #include #include #include ISC_LANG_BEGINDECLS #define DNS_RDATASLAB_FORCE 0x1 #define DNS_RDATASLAB_EXACT 0x2 #define DNS_RDATASLAB_OFFLINE 0x01 /* RRSIG is for offline DNSKEY */ struct dns_slabheader_proof { dns_name_t name; void *neg; void *negsig; dns_rdatatype_t type; }; struct dns_slabheader { _Atomic(uint16_t) attributes; /*% * Locked by the owning node's lock. */ dns_trust_t trust; uint32_t serial; dns_ttl_t ttl; dns_typepair_t type; _Atomic(uint16_t) count; /*%< * Monotonically increased every time this rdataset is bound so that * it is used as the base of the starting point in DNS responses * when the "cyclic" rrset-order is required. */ unsigned int resign_lsb : 1; isc_stdtime_t resign; unsigned int heap_index; /*%< * Used for TTL-based cache cleaning. */ isc_stdtime_t last_used; _Atomic(uint32_t) last_refresh_fail_ts; dns_slabheader_proof_t *noqname; dns_slabheader_proof_t *closest; /*%< * We don't use the LIST macros, because the LIST structure has * both head and tail pointers, and is doubly linked. */ struct dns_slabheader *next; /*%< * If this is the top header for an rdataset, 'next' points * to the top header for the next rdataset (i.e., the next type). * Otherwise, it points up to the header whose down pointer points * at this header. */ struct dns_slabheader *down; /*%< * Points to the header for the next older version of * this rdataset. */ dns_db_t *db; dns_dbnode_t *node; /*%< * The database and database node objects containing * this rdataset, if any. */ ISC_LINK(struct dns_slabheader) link; /*% * Case vector. If the bit is set then the corresponding * character in the owner name needs to be AND'd with 0x20, * rendering that character upper case. */ unsigned char upper[32]; isc_heap_t *heap; dns_gluelist_t *gluelist; }; enum { DNS_SLABHEADERATTR_NONEXISTENT = 1 << 0, DNS_SLABHEADERATTR_STALE = 1 << 1, DNS_SLABHEADERATTR_IGNORE = 1 << 2, DNS_SLABHEADERATTR_NXDOMAIN = 1 << 3, DNS_SLABHEADERATTR_RESIGN = 1 << 4, DNS_SLABHEADERATTR_STATCOUNT = 1 << 5, DNS_SLABHEADERATTR_OPTOUT = 1 << 6, DNS_SLABHEADERATTR_NEGATIVE = 1 << 7, DNS_SLABHEADERATTR_PREFETCH = 1 << 8, DNS_SLABHEADERATTR_CASESET = 1 << 9, DNS_SLABHEADERATTR_ZEROTTL = 1 << 10, DNS_SLABHEADERATTR_CASEFULLYLOWER = 1 << 11, DNS_SLABHEADERATTR_ANCIENT = 1 << 12, DNS_SLABHEADERATTR_STALE_WINDOW = 1 << 13, }; /* clang-format off : RemoveParentheses */ #define DNS_SLABHEADER_GETATTR(header, attribute) \ (atomic_load_acquire(&(header)->attributes) & (attribute)) /* clang-format on */ #define DNS_SLABHEADER_SETATTR(header, attribute) \ atomic_fetch_or_release(&(header)->attributes, attribute) #define DNS_SLABHEADER_CLRATTR(header, attribute) \ atomic_fetch_and_release(&(header)->attributes, ~(attribute)) extern dns_rdatasetmethods_t dns_rdataslab_rdatasetmethods; /*** *** Functions ***/ isc_result_t dns_rdataslab_fromrdataset(dns_rdataset_t *rdataset, isc_mem_t *mctx, isc_region_t *region, unsigned int reservelen, uint32_t limit); /*%< * Slabify a rdataset. The slab area will be allocated and returned * in 'region'. * * Requires: *\li 'rdataset' is valid. * * Ensures: *\li 'region' will have base pointing to the start of allocated memory, * with the slabified region beginning at region->base + reservelen. * region->length contains the total length allocated. * * Returns: *\li ISC_R_SUCCESS - successful completion *\li ISC_R_NOMEMORY - no memory. *\li XXX others */ unsigned int dns_rdataslab_size(unsigned char *slab, unsigned int reservelen); /*%< * Return the total size of an rdataslab. * * Requires: *\li 'slab' points to a slab. * * Returns: *\li The number of bytes in the slab, including the reservelen. */ unsigned int dns_rdataslab_rdatasize(unsigned char *slab, unsigned int reservelen); /*%< * Return the size of the rdata in an rdataslab. * * Requires: *\li 'slab' points to a slab. */ unsigned int dns_rdataslab_count(unsigned char *slab, unsigned int reservelen); /*%< * Return the number of records in the rdataslab * * Requires: *\li 'slab' points to a slab. * * Returns: *\li The number of records in the slab. */ 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, uint32_t maxrrperset, unsigned char **tslabp); /*%< * Merge 'oslab' and 'nslab'. */ 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); /*%< * Subtract 'sslab' from 'mslab'. If 'exact' is true then all elements * of 'sslab' must exist in 'mslab'. * * XXX * valid flags are DNS_RDATASLAB_EXACT */ bool dns_rdataslab_equal(unsigned char *slab1, unsigned char *slab2, unsigned int reservelen); /*%< * Compare two rdataslabs for equality. This does _not_ do a full * DNSSEC comparison. * * Requires: *\li 'slab1' and 'slab2' point to slabs. * * Returns: *\li true if the slabs are equal, false otherwise. */ bool dns_rdataslab_equalx(unsigned char *slab1, unsigned char *slab2, unsigned int reservelen, dns_rdataclass_t rdclass, dns_rdatatype_t type); /*%< * Compare two rdataslabs for DNSSEC equality. * * Requires: *\li 'slab1' and 'slab2' point to slabs. * * Returns: *\li true if the slabs are equal, #false otherwise. */ dns_slabheader_t * dns_slabheader_fromrdataset(const dns_rdataset_t *rdataset); /*% * Returns the address of the slab header for a slab-type rdataset. */ void * dns_slabheader_raw(dns_slabheader_t *header); /*% * Returns the address of the raw memory following a dns_slabheader. */ void dns_slabheader_setownercase(dns_slabheader_t *header, const dns_name_t *name); /*%< * Store the casing of 'name', into a bitfield in 'header'. */ void dns_slabheader_copycase(dns_slabheader_t *dest, dns_slabheader_t *src); /*%< * Copy the casing of 'src', into 'dest'. */ void dns_slabheader_reset(dns_slabheader_t *h, dns_db_t *db, dns_dbnode_t *node); /*%< * Reset an rdataslab header 'h' so it can be used to store data in * database 'db' and node 'node'. */ dns_slabheader_t * dns_slabheader_new(dns_db_t *db, dns_dbnode_t *node); /*%< * Allocate memory for an rdataslab header and initialize it for use * in database 'db'/node 'node'. */ void dns_slabheader_destroy(dns_slabheader_t **headerp); /*%< * Free all memory associated with '*headerp'. */ void dns_slabheader_freeproof(isc_mem_t *mctx, dns_slabheader_proof_t **proof); /*%< * Free all memory associated with a nonexistence proof. */ ISC_LANG_ENDDECLS