diff options
Diffstat (limited to '')
| -rw-r--r-- | external/unbound/validator/val_nsec3.h | 380 |
1 files changed, 380 insertions, 0 deletions
diff --git a/external/unbound/validator/val_nsec3.h b/external/unbound/validator/val_nsec3.h new file mode 100644 index 000000000..d619d672d --- /dev/null +++ b/external/unbound/validator/val_nsec3.h @@ -0,0 +1,380 @@ +/* + * 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 */ |