/* * dname.h * * dname definitions * * a Net::DNS like library for C * * (c) NLnet Labs, 2004-2006 * * See the file LICENSE for the license */ /** * \file dname.h * * dname contains function to read and manipulate domain names. * * Example domain names are "www.nlnetlabs.nl." and "." (the root) * * If a domain name ends with a dot ("."), it is called a Fully Qualified * Domain Name (FQDN). In certain places (for instance when reading a zone * file), an origin (which is just another domain name) non-FQDNs will be * placed after the current. For instance, if i have a zone file where the * origin has been set to "nl.", and my file contains the name * "www.nlnetlabs", it will result in "www.nlnetlabs.nl.". Internally, dnames are * always absolute (the dot is added when it is missing and there is no origin). * * An FQDN is also * known as an absolute domain name, therefore the function to check this is * called \ref ldns_dname_str_absolute * * Domain names are stored in \ref ldns_rdf structures, with the type * \ref LDNS_RDF_TYPE_DNAME * * This module is *NOT* about the RR type called DNAME. */ #ifndef LDNS_DNAME_H #define LDNS_DNAME_H #include #include #ifdef __cplusplus extern "C" { #endif #define LDNS_DNAME_NORMALIZE tolower /** * concatenates two dnames together * \param[in] rd1 the leftside * \param[in] rd2 the rightside * \return a new rdf with leftside/rightside */ ldns_rdf *ldns_dname_cat_clone(const ldns_rdf *rd1, const ldns_rdf *rd2); /** * concatenates rd2 after rd1 (rd2 is copied, rd1 is modified) * \param[in] rd1 the leftside * \param[in] rd2 the rightside * \return LDNS_STATUS_OK on success */ ldns_status ldns_dname_cat(ldns_rdf *rd1, ldns_rdf *rd2); /** * Returns a clone of the given dname with the labels * reversed * \param[in] d the dname to reverse * \return clone of the dname with the labels reversed. */ ldns_rdf *ldns_dname_reverse(const ldns_rdf *d); /** * Clones the given dname from the nth label on * \param[in] d The dname to clone * \param[in] n the label nr to clone from, if this is 0, the complete * dname is cloned * \return A newly allocated *rdf structure, containing the cloned dname, * or NULL if either d was NULL, not a dname, or if n >= * label_count */ ldns_rdf * ldns_dname_clone_from(const ldns_rdf *d, uint16_t n); /** * chop one label off the left side of a dname. so * wwww.nlnetlabs.nl, becomes nlnetlabs.nl * This new name is a clone and must be freed with ldns_deep_free() * \param[in] d the dname to chop * \return the remaining dname */ ldns_rdf *ldns_dname_left_chop(const ldns_rdf *d); /** * count the number of labels inside a LDNS_RDF_DNAME type rdf. * \param[in] *r the rdf * \return the number of labels */ uint8_t ldns_dname_label_count(const ldns_rdf *r); /** * creates a new dname rdf from a string. * \param[in] str string to use * \return ldns_rdf* or NULL in case of an error */ ldns_rdf *ldns_dname_new_frm_str(const char *str); /** * Create a new dname rdf from a string * \param[in] s the size of the new dname * \param[in] *data pointer to the actual data * \return ldns_rdf* */ ldns_rdf *ldns_dname_new(uint16_t s, void *data); /** * Create a new dname rdf from data (the data is copied) * \param[in] size the size of the data * \param[in] *data pointer to the actual data * \return ldns_rdf* */ ldns_rdf *ldns_dname_new_frm_data(uint16_t size, const void *data); /** * Put a dname into canonical fmt - ie. lowercase it * \param[in] rdf the dname to lowercase * \return void */ void ldns_dname2canonical(const ldns_rdf *rdf); /** * test wether the name sub falls under parent (i.e. is a subdomain * of parent). This function will return false if the given dnames are * equal. * \param[in] sub the name to test * \param[in] parent the parent's name * \return true if sub falls under parent, otherwise false */ bool ldns_dname_is_subdomain(const ldns_rdf *sub, const ldns_rdf *parent); /** * Compares the two dname rdf's according to the algorithm for ordering * in RFC4034 Section 6. * \param[in] dname1 First dname rdf to compare * \param[in] dname2 Second dname rdf to compare * \return -1 if dname1 comes before dname2, 1 if dname1 comes after dname2, and 0 if they are equal. */ int ldns_dname_compare(const ldns_rdf *dname1, const ldns_rdf *dname2); /** * Checks whether the dname matches the given wildcard * \param[in] dname The dname to check * \param[in] wildcard The wildcard to check with * \return 1 If the wildcard matches, OR if 'wildcard' is not a wildcard and * the names are *exactly* the same * 0 If the wildcard does not match, or if it is not a wildcard and * the names are not the same */ int ldns_dname_match_wildcard(const ldns_rdf *dname, const ldns_rdf *wildcard); /** * check if middle lays in the interval defined by prev and next * prev <= middle < next. This is usefull for nsec checking * \param[in] prev the previous dname * \param[in] middle the dname to check * \param[in] next the next dname * return 0 on error or unknown, -1 when middle is in the interval, +1 when not */ int ldns_dname_interval(const ldns_rdf *prev, const ldns_rdf *middle, const ldns_rdf *next); /** * Checks whether the given dname string is absolute (i.e. ends with a '.') * \param[in] *dname_str a string representing the dname * \return true or false */ bool ldns_dname_str_absolute(const char *dname_str); /** * look inside the rdf and if it is an LDNS_RDF_TYPE_DNAME * try and retrieve a specific label. The labels are numbered * starting from 0 (left most). * \param[in] rdf the rdf to look in * \param[in] labelpos return the label with this number * \return a ldns_rdf* with the label as name or NULL on error */ ldns_rdf * ldns_dname_label(const ldns_rdf *rdf, uint8_t labelpos); /** * Check if dname is a wildcard, starts with *. * \param[in] dname: the rdf to look in * \return true if a wildcard, false if not. */ int ldns_dname_is_wildcard(const ldns_rdf* dname); #ifdef __cplusplus } #endif #endif /* LDNS_DNAME_H */