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Diffstat (limited to 'external/unbound/util/data/dname.h')
| -rw-r--r-- | external/unbound/util/data/dname.h | 304 |
1 files changed, 304 insertions, 0 deletions
diff --git a/external/unbound/util/data/dname.h b/external/unbound/util/data/dname.h new file mode 100644 index 000000000..ae2fbadc1 --- /dev/null +++ b/external/unbound/util/data/dname.h @@ -0,0 +1,304 @@ +/* + * util/data/dname.h - domain name routines + * + * 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 functions to deal with domain names (dnames). + * + * Some of the functions deal with domain names as a wireformat buffer, + * with a length. + */ + +#ifndef UTIL_DATA_DNAME_H +#define UTIL_DATA_DNAME_H +#include "util/storage/lruhash.h" +struct sldns_buffer; + +/** max number of compression ptrs to follow */ +#define MAX_COMPRESS_PTRS 256 + +/** + * Determine length of dname in buffer, no compression ptrs allowed, + * @param query: the ldns buffer, current position at start of dname. + * at end, position is at end of the dname. + * @return: 0 on parse failure, or length including ending 0 of dname. + */ +size_t query_dname_len(struct sldns_buffer* query); + +/** + * Determine if dname in memory is correct. no compression ptrs allowed. + * @param dname: where dname starts in memory. + * @param len: dname is not allowed to exceed this length (i.e. of allocation). + * @return length of dname if dname is ok, 0 on a parse error. + */ +size_t dname_valid(uint8_t* dname, size_t len); + +/** lowercase query dname */ +void query_dname_tolower(uint8_t* dname); + +/** + * lowercase pkt dname (follows compression pointers) + * @param pkt: the packet, used to follow compression pointers. Position + * is unchanged. + * @param dname: start of dname in packet. + */ +void pkt_dname_tolower(struct sldns_buffer* pkt, uint8_t* dname); + +/** + * Compare query dnames (uncompressed storage). The Dnames passed do not + * have to be lowercased, comparison routine does this. + * + * This routine is special, in that the comparison that it does corresponds + * with the canonical comparison needed when comparing dnames inside rdata + * for RR types that need canonicalization. That means that the first byte + * that is smaller (possibly after lowercasing) makes an RR smaller, or the + * shortest name makes an RR smaller. + * + * This routine does not compute the canonical order needed for NSEC + * processing. + * + * Dnames have to be valid format. + * @param d1: dname to compare + * @param d2: dname to compare + * @return: -1, 0, or +1 depending on comparison results. + * Sort order is first difference found. not the canonical ordering. + */ +int query_dname_compare(uint8_t* d1, uint8_t* d2); + +/** + * Determine correct, compressed, dname present in packet. + * Checks for parse errors. + * @param pkt: packet to read from (from current start position). + * @return: 0 on parse error. + * At exit the position is right after the (compressed) dname. + * Compression pointers are followed and checked for loops. + * The uncompressed wireformat length is returned. + */ +size_t pkt_dname_len(struct sldns_buffer* pkt); + +/** + * Compare dnames in packet (compressed). Dnames must be valid. + * routine performs lowercasing, so the packet casing is preserved. + * @param pkt: packet, used to resolve compression pointers. + * @param d1: dname to compare + * @param d2: dname to compare + * @return: -1, 0, or +1 depending on comparison results. + * Sort order is first difference found. not the canonical ordering. + */ +int dname_pkt_compare(struct sldns_buffer* pkt, uint8_t* d1, uint8_t* d2); + +/** + * Hash dname, label by label, lowercasing, into hashvalue. + * Dname in query format (not compressed). + * @param dname: dname to hash. + * @param h: initial hash value. + * @return: result hash value. + */ +hashvalue_t dname_query_hash(uint8_t* dname, hashvalue_t h); + +/** + * Hash dname, label by label, lowercasing, into hashvalue. + * Dname in pkt format (compressed). + * @param pkt: packet, for resolving compression pointers. + * @param dname: dname to hash, pointer to the pkt buffer. + * Must be valid format. No loops, etc. + * @param h: initial hash value. + * @return: result hash value. + * Result is the same as dname_query_hash, even if compression is used. + */ +hashvalue_t dname_pkt_hash(struct sldns_buffer* pkt, uint8_t* dname, hashvalue_t h); + +/** + * Copy over a valid dname and decompress it. + * @param pkt: packet to resolve compression pointers. + * @param to: buffer of size from pkt_len function to hold result. + * @param dname: pointer into packet where dname starts. + */ +void dname_pkt_copy(struct sldns_buffer* pkt, uint8_t* to, uint8_t* dname); + +/** + * Copy over a valid dname to a packet. + * @param pkt: packet to copy to. + * @param dname: dname to copy. + * @return: 0 if not enough space in buffer. + */ +int dname_buffer_write(struct sldns_buffer* pkt, uint8_t* dname); + +/** + * Count the number of labels in an uncompressed dname in memory. + * @param dname: pointer to uncompressed dname. + * @return: count of labels, including root label, "com." has 2 labels. + */ +int dname_count_labels(uint8_t* dname); + +/** + * Count labels and dname length both, for uncompressed dname in memory. + * @param dname: pointer to uncompressed dname. + * @param size: length of dname, including root label. + * @return: count of labels, including root label, "com." has 2 labels. + */ +int dname_count_size_labels(uint8_t* dname, size_t* size); + +/** + * Compare dnames, sorted not canonical, but by label. + * Such that zone contents follows zone apex. + * @param d1: first dname. pointer to uncompressed wireformat. + * @param labs1: number of labels in first dname. + * @param d2: second dname. pointer to uncompressed wireformat. + * @param labs2: number of labels in second dname. + * @param mlabs: number of labels that matched exactly (the shared topdomain). + * @return: 0 for equal, -1 smaller, or +1 d1 larger than d2. + */ +int dname_lab_cmp(uint8_t* d1, int labs1, uint8_t* d2, int labs2, int* mlabs); + +/** + * See if domain name d1 is a strict subdomain of d2. + * That is a subdomain, but not equal. + * @param d1: domain name, uncompressed wireformat + * @param labs1: number of labels in d1, including root label. + * @param d2: domain name, uncompressed wireformat + * @param labs2: number of labels in d2, including root label. + * @return true if d1 is a subdomain of d2, but not equal to d2. + */ +int dname_strict_subdomain(uint8_t* d1, int labs1, uint8_t* d2, int labs2); + +/** + * Like dname_strict_subdomain but counts labels + * @param d1: domain name, uncompressed wireformat + * @param d2: domain name, uncompressed wireformat + * @return true if d1 is a subdomain of d2, but not equal to d2. + */ +int dname_strict_subdomain_c(uint8_t* d1, uint8_t* d2); + +/** + * Counts labels. Tests is d1 is a subdomain of d2. + * @param d1: domain name, uncompressed wireformat + * @param d2: domain name, uncompressed wireformat + * @return true if d1 is a subdomain of d2. + */ +int dname_subdomain_c(uint8_t* d1, uint8_t* d2); + +/** + * Debug helper. Print wireformat dname to output. + * @param out: like stdout or a file. + * @param pkt: if not NULL, the packet for resolving compression ptrs. + * @param dname: pointer to (start of) dname. + */ +void dname_print(FILE* out, struct sldns_buffer* pkt, uint8_t* dname); + +/** + * Debug helper. Print dname to given string buffer (string buffer must + * be at least 255 chars + 1 for the 0, in printable form. + * This may lose information (? for nonprintable characters, or & if + * the name is too long, # for a bad label length). + * @param dname: uncompressed wireformat. + * @param str: buffer of 255+1 length. + */ +void dname_str(uint8_t* dname, char* str); + +/** + * Returns true if the uncompressed wireformat dname is the root "." + * @param dname: the dname to check + * @return true if ".", false if not. + */ +int dname_is_root(uint8_t* dname); + +/** + * Snip off first label from a dname, returning the parent zone. + * @param dname: from what to strip off. uncompressed wireformat. + * @param len: length, adjusted to become less. + * @return stripped off, or "." if input was ".". + */ +void dname_remove_label(uint8_t** dname, size_t* len); + +/** + * Snip off first N labels from a dname, returning the parent zone. + * @param dname: from what to strip off. uncompressed wireformat. + * @param len: length, adjusted to become less. + * @param n: number of labels to strip off (from the left). + * if 0, nothing happens. + * @return stripped off, or "." if input was ".". + */ +void dname_remove_labels(uint8_t** dname, size_t* len, int n); + +/** + * Count labels for the RRSIG signature label field. + * Like a normal labelcount, but "*" wildcard and "." root are not counted. + * @param dname: valid uncompressed wireformat. + * @return number of labels like in RRSIG; '*' and '.' are not counted. + */ +int dname_signame_label_count(uint8_t* dname); + +/** + * Return true if the label is a wildcard, *.example.com. + * @param dname: valid uncompressed wireformat. + * @return true if wildcard, or false. + */ +int dname_is_wild(uint8_t* dname); + +/** + * Compare dnames, Canonical in rfc4034 sense, but by label. + * Such that zone contents follows zone apex. + * + * @param d1: first dname. pointer to uncompressed wireformat. + * @param labs1: number of labels in first dname. + * @param d2: second dname. pointer to uncompressed wireformat. + * @param labs2: number of labels in second dname. + * @param mlabs: number of labels that matched exactly (the shared topdomain). + * @return: 0 for equal, -1 smaller, or +1 d1 larger than d2. + */ +int dname_canon_lab_cmp(uint8_t* d1, int labs1, uint8_t* d2, int labs2, + int* mlabs); + +/** + * Canonical dname compare. Takes care of counting labels. + * Per rfc 4034 canonical order. + * + * @param d1: first dname. pointer to uncompressed wireformat. + * @param d2: second dname. pointer to uncompressed wireformat. + * @return: 0 for equal, -1 smaller, or +1 d1 larger than d2. + */ +int dname_canonical_compare(uint8_t* d1, uint8_t* d2); + +/** + * Get the shared topdomain between two names. Root "." or longer. + * @param d1: first dname. pointer to uncompressed wireformat. + * @param d2: second dname. pointer to uncompressed wireformat. + * @return pointer to shared topdomain. Ptr to a part of d1. + */ +uint8_t* dname_get_shared_topdomain(uint8_t* d1, uint8_t* d2); + +#endif /* UTIL_DATA_DNAME_H */ |