/* * validator/val_nsec3.h - validator NSEC3 denial of existance functions. * * Copyright (c) 2007, NLnet Labs. All rights reserved. * * This software is open source. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of the NLNET LABS nor the names of its contributors may * be used to endorse or promote products derived from this software without * specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /** * \file * * This file contains helper functions for the validator module. * The functions help with NSEC3 checking, the different NSEC3 proofs * for denial of existance, and proofs for presence of types. * * NSEC3 * 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Hash Alg. | Flags | Iterations | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Salt Length | Salt / * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Hash Length | Next Hashed Owner Name / * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * / Type Bit Maps / * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * * NSEC3PARAM * 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Hash Alg. | Flags | Iterations | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Salt Length | Salt / * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * */ #ifndef VALIDATOR_VAL_NSEC3_H #define VALIDATOR_VAL_NSEC3_H #include "util/rbtree.h" #include "util/data/packed_rrset.h" struct val_env; struct regional; struct module_env; struct ub_packed_rrset_key; struct reply_info; struct query_info; struct key_entry_key; struct sldns_buffer; /** * 0 1 2 3 4 5 6 7 * +-+-+-+-+-+-+-+-+ * | |O| * +-+-+-+-+-+-+-+-+ * The OPT-OUT bit in the NSEC3 flags field. * If enabled, there can be zero or more unsigned delegations in the span. * If disabled, there are zero unsigned delegations in the span. */ #define NSEC3_OPTOUT 0x01 /** * The unknown flags in the NSEC3 flags field. * They must be zero, or the NSEC3 is ignored. */ #define NSEC3_UNKNOWN_FLAGS 0xFE /** The SHA1 hash algorithm for NSEC3 */ #define NSEC3_HASH_SHA1 0x01 /** * Determine if the set of NSEC3 records provided with a response prove NAME * ERROR. This means that the NSEC3s prove a) the closest encloser exists, * b) the direct child of the closest encloser towards qname doesn't exist, * and c) *.closest encloser does not exist. * * @param env: module environment with temporary region and buffer. * @param ve: validator environment, with iteration count settings. * @param list: array of RRsets, some of which are NSEC3s. * @param num: number of RRsets in the array to examine. * @param qinfo: query that is verified for. * @param kkey: key entry that signed the NSEC3s. * @return: * sec_status SECURE of the Name Error is proven by the NSEC3 RRs, * BOGUS if not, INSECURE if all of the NSEC3s could be validly ignored. */ enum sec_status nsec3_prove_nameerror(struct module_env* env, struct val_env* ve, struct ub_packed_rrset_key** list, size_t num, struct query_info* qinfo, struct key_entry_key* kkey); /** * Determine if the NSEC3s provided in a response prove the NOERROR/NODATA * status. There are a number of different variants to this: * * 1) Normal NODATA -- qname is matched to an NSEC3 record, type is not * present. * * 2) ENT NODATA -- because there must be NSEC3 record for * empty-non-terminals, this is the same as #1. * * 3) NSEC3 ownername NODATA -- qname matched an existing, lone NSEC3 * ownername, but qtype was not NSEC3. NOTE: as of nsec-05, this case no * longer exists. * * 4) Wildcard NODATA -- A wildcard matched the name, but not the type. * * 5) Opt-In DS NODATA -- the qname is covered by an opt-in span and qtype == * DS. (or maybe some future record with the same parent-side-only property) * * @param env: module environment with temporary region and buffer. * @param ve: validator environment, with iteration count settings. * @param list: array of RRsets, some of which are NSEC3s. * @param num: number of RRsets in the array to examine. * @param qinfo: query that is verified for. * @param kkey: key entry that signed the NSEC3s. * @return: * sec_status SECURE of the proposition is proven by the NSEC3 RRs, * BOGUS if not, INSECURE if all of the NSEC3s could be validly ignored. */ enum sec_status nsec3_prove_nodata(struct module_env* env, struct val_env* ve, struct ub_packed_rrset_key** list, size_t num, struct query_info* qinfo, struct key_entry_key* kkey); /** * Prove that a positive wildcard match was appropriate (no direct match * RRset). * * @param env: module environment with temporary region and buffer. * @param ve: validator environment, with iteration count settings. * @param list: array of RRsets, some of which are NSEC3s. * @param num: number of RRsets in the array to examine. * @param qinfo: query that is verified for. * @param kkey: key entry that signed the NSEC3s. * @param wc: The purported wildcard that matched. This is the wildcard name * as *.wildcard.name., with the *. label already removed. * @return: * sec_status SECURE of the proposition is proven by the NSEC3 RRs, * BOGUS if not, INSECURE if all of the NSEC3s could be validly ignored. */ enum sec_status nsec3_prove_wildcard(struct module_env* env, struct val_env* ve, struct ub_packed_rrset_key** list, size_t num, struct query_info* qinfo, struct key_entry_key* kkey, uint8_t* wc); /** * Prove that a DS response either had no DS, or wasn't a delegation point. * * Fundamentally there are two cases here: normal NODATA and Opt-In NODATA. * * @param env: module environment with temporary region and buffer. * @param ve: validator environment, with iteration count settings. * @param list: array of RRsets, some of which are NSEC3s. * @param num: number of RRsets in the array to examine. * @param qinfo: query that is verified for. * @param kkey: key entry that signed the NSEC3s. * @param reason: string for bogus result. * @return: * sec_status SECURE of the proposition is proven by the NSEC3 RRs, * BOGUS if not, INSECURE if all of the NSEC3s could be validly ignored. * or if there was no DS in an insecure (i.e., opt-in) way, * INDETERMINATE if it was clear that this wasn't a delegation point. */ enum sec_status nsec3_prove_nods(struct module_env* env, struct val_env* ve, struct ub_packed_rrset_key** list, size_t num, struct query_info* qinfo, struct key_entry_key* kkey, char** reason); /** * Prove NXDOMAIN or NODATA. * * @param env: module environment with temporary region and buffer. * @param ve: validator environment, with iteration count settings. * @param list: array of RRsets, some of which are NSEC3s. * @param num: number of RRsets in the array to examine. * @param qinfo: query that is verified for. * @param kkey: key entry that signed the NSEC3s. * @param nodata: if return value is secure, this indicates if nodata or * nxdomain was proven. * @return: * sec_status SECURE of the proposition is proven by the NSEC3 RRs, * BOGUS if not, INSECURE if all of the NSEC3s could be validly ignored. */ enum sec_status nsec3_prove_nxornodata(struct module_env* env, struct val_env* ve, struct ub_packed_rrset_key** list, size_t num, struct query_info* qinfo, struct key_entry_key* kkey, int* nodata); /** * The NSEC3 hash result storage. * Consists of an rbtree, with these nodes in it. * The nodes detail how a set of parameters (from nsec3 rr) plus * a dname result in a hash. */ struct nsec3_cached_hash { /** rbtree node, key is this structure */ rbnode_t node; /** where are the parameters for conversion, in this rrset data */ struct ub_packed_rrset_key* nsec3; /** where are the parameters for conversion, this RR number in data */ int rr; /** the name to convert */ uint8_t* dname; /** length of the dname */ size_t dname_len; /** the hash result (not base32 encoded) */ uint8_t* hash; /** length of hash in bytes */ size_t hash_len; /** the hash result in base32 encoding */ uint8_t* b32; /** length of base32 encoding (as a label) */ size_t b32_len; }; /** * Rbtree for hash cache comparison function. * @param c1: key 1. * @param c2: key 2. * @return: comparison code, -1, 0, 1, of the keys. */ int nsec3_hash_cmp(const void* c1, const void* c2); /** * Obtain the hash of an owner name. * Used internally by the nsec3 proof functions in this file. * published to enable unit testing of hash algorithms and cache. * * @param table: the cache table. Must be inited at start. * @param region: scratch region to use for allocation. * This region holds the tree, if you wipe the region, reinit the tree. * @param buf: temporary buffer. * @param nsec3: the rrset with parameters * @param rr: rr number from d that has the NSEC3 parameters to hash to. * @param dname: name to hash * This pointer is used inside the tree, assumed region-alloced. * @param dname_len: the length of the name. * @param hash: the hash node is returned on success. * @return: * 1 on success, either from cache or newly hashed hash is returned. * 0 on a malloc failure. * -1 if the NSEC3 rr was badly formatted (i.e. formerr). */ int nsec3_hash_name(rbtree_t* table, struct regional* region, struct sldns_buffer* buf, struct ub_packed_rrset_key* nsec3, int rr, uint8_t* dname, size_t dname_len, struct nsec3_cached_hash** hash); /** * Get next owner name, converted to base32 encoding and with the * zone name (taken from the nsec3 owner name) appended. * @param rrset: the NSEC3 rrset. * @param r: the rr num of the nsec3 in the rrset. * @param buf: buffer to store name in * @param max: size of buffer. * @return length of name on success. 0 on failure (buffer too short or * bad format nsec3 record). */ size_t nsec3_get_nextowner_b32(struct ub_packed_rrset_key* rrset, int r, uint8_t* buf, size_t max); /** * Convert hash into base32 encoding and with the * zone name appended. * @param hash: hashed buffer * @param hashlen: length of hash * @param zone: name of zone * @param zonelen: length of zonename. * @param buf: buffer to store name in * @param max: size of buffer. * @return length of name on success. 0 on failure (buffer too short or * bad format nsec3 record). */ size_t nsec3_hash_to_b32(uint8_t* hash, size_t hashlen, uint8_t* zone, size_t zonelen, uint8_t* buf, size_t max); /** * Get NSEC3 parameters out of rr. * @param rrset: the NSEC3 rrset. * @param r: the rr num of the nsec3 in the rrset. * @param algo: nsec3 hash algo. * @param iter: iteration count. * @param salt: ptr to salt inside rdata. * @param saltlen: length of salt. * @return 0 if bad formatted, unknown nsec3 hash algo, or unknown flags set. */ int nsec3_get_params(struct ub_packed_rrset_key* rrset, int r, int* algo, size_t* iter, uint8_t** salt, size_t* saltlen); /** * Get NSEC3 hashed in a buffer * @param buf: buffer for temp use. * @param nm: name to hash * @param nmlen: length of nm. * @param algo: algo to use, must be known. * @param iter: iterations * @param salt: salt for nsec3 * @param saltlen: length of salt. * @param res: result of hash stored here. * @param max: maximum space for result. * @return 0 on failure, otherwise bytelength stored. */ size_t nsec3_get_hashed(struct sldns_buffer* buf, uint8_t* nm, size_t nmlen, int algo, size_t iter, uint8_t* salt, size_t saltlen, uint8_t* res, size_t max); /** * see if NSEC3 RR contains given type * @param rrset: NSEC3 rrset * @param r: RR in rrset * @param type: in host order to check bit for. * @return true if bit set, false if not or error. */ int nsec3_has_type(struct ub_packed_rrset_key* rrset, int r, uint16_t type); /** * return if nsec3 RR has the optout flag * @param rrset: NSEC3 rrset * @param r: RR in rrset * @return true if optout, false on error or not optout */ int nsec3_has_optout(struct ub_packed_rrset_key* rrset, int r); /** * Return nsec3 RR next hashed owner name * @param rrset: NSEC3 rrset * @param r: RR in rrset * @param next: ptr into rdata to next owner hash * @param nextlen: length of hash. * @return false on malformed */ int nsec3_get_nextowner(struct ub_packed_rrset_key* rrset, int r, uint8_t** next, size_t* nextlen); /** * nsec3Covers * Given a hash and a candidate NSEC3Record, determine if that NSEC3Record * covers the hash. Covers specifically means that the hash is in between * the owner and next hashes and does not equal either. * * @param zone: the zone name. * @param hash: the hash of the name * @param rrset: the rrset of the NSEC3. * @param rr: which rr in the rrset. * @param buf: temporary buffer. * @return true if covers, false if not. */ int nsec3_covers(uint8_t* zone, struct nsec3_cached_hash* hash, struct ub_packed_rrset_key* rrset, int rr, struct sldns_buffer* buf); #endif /* VALIDATOR_VAL_NSEC3_H */