src/resolve/resolved-dns-rr.c

	resolved-dns-rr.c revision 322345fdb9865ef2477fba8e4bdde0e1183ef505
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

/***
  This file is part of systemd.

  Copyright 2014 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.

  systemd is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#include "resolved-dns-domain.h"
#include "resolved-dns-rr.h"

void dns_resource_key_free(DnsResourceKey *key) {
        if (!key)
                return;

        free(key->name);
        zero(*key);
}

unsigned long dns_resource_key_hash_func(const void *i, const uint8_t hash_key[HASH_KEY_SIZE]) {
        const DnsResourceKey *k = i;
        unsigned long ul;

        ul = dns_name_hash_func(k->name, hash_key);
        ul = ul * hash_key[0] + ul + k->class;
        ul = ul * hash_key[1] + ul + k->type;

        return ul;
}

int dns_resource_key_compare_func(const void *a, const void *b) {
        const DnsResourceKey *x = a, *y = b;
        int ret;

        ret = dns_name_compare_func(x->name, y->name);
        if (ret != 0)
                return ret;

        if (x->type < y->type)
                return -1;
        if (x->type > y->type)
                return 1;

        if (x->class < y->class)
                return -1;
        if (x->class > y->class)
                return 1;

        return 0;
}

DnsResourceRecord* dns_resource_record_new(void) {
        DnsResourceRecord *rr;

        rr = new0(DnsResourceRecord, 1);
        if (!rr)
                return NULL;

        rr->n_ref = 1;
        return rr;
}

DnsResourceRecord* dns_resource_record_ref(DnsResourceRecord *rr) {
        if (!rr)
                return NULL;

        assert(rr->n_ref > 0);
        rr->n_ref++;

        return rr;
}

DnsResourceRecord* dns_resource_record_unref(DnsResourceRecord *rr) {
        if (!rr)
                return NULL;

        assert(rr->n_ref > 0);

        if (rr->n_ref > 1) {
                rr->n_ref--;
                return NULL;
        }

        if (IN_SET(rr->key.type, DNS_TYPE_PTR, DNS_TYPE_NS, DNS_TYPE_CNAME))
                free(rr->ptr.name);
        else if (rr->key.type == DNS_TYPE_HINFO) {
                free(rr->hinfo.cpu);
                free(rr->hinfo.os);
        } else if (!IN_SET(rr->key.type, DNS_TYPE_A, DNS_TYPE_AAAA))
                free(rr->generic.data);

        dns_resource_key_free(&rr->key);
        free(rr);

        return NULL;
}

DnsResourceRecord** dns_resource_record_freev(DnsResourceRecord **rrs, unsigned n) {
        unsigned i;

        assert(n == 0 || rrs);

        for (i = 0; i < n; i++)
                dns_resource_record_unref(rrs[i]);

        free(rrs);
        return NULL;
}

int dns_resource_record_equal(const DnsResourceRecord *a, const DnsResourceRecord *b) {
        int r;

        assert(a);
        assert(b);

        r = dns_name_equal(a->key.name, b->key.name);
        if (r <= 0)
                return r;

        if (a->key.class != b->key.class)
                return 0;

        if (a->key.type != b->key.type)
                return 0;

        if (IN_SET(a->key.type, DNS_TYPE_PTR, DNS_TYPE_NS, DNS_TYPE_CNAME))
                return dns_name_equal(a->ptr.name, b->ptr.name);
        else if (a->key.type == DNS_TYPE_HINFO)
                return strcasecmp(a->hinfo.cpu, b->hinfo.cpu) == 0 &&
                       strcasecmp(a->hinfo.os, b->hinfo.os) == 0;
        else if (a->key.type == DNS_TYPE_A)
                return memcmp(&a->a.in_addr, &b->a.in_addr, sizeof(struct in_addr)) == 0;
        else if (a->key.type == DNS_TYPE_AAAA)
                return memcmp(&a->aaaa.in6_addr, &b->aaaa.in6_addr, sizeof(struct in6_addr)) == 0;
        else
                return a->generic.size == b->generic.size &&
                        memcmp(a->generic.data, b->generic.data, a->generic.size) == 0;
}

const char *dns_class_to_string(uint16_t class) {

        switch (class) {

        case DNS_CLASS_IN:
                return "IN";

        case DNS_CLASS_ANY:
                return "ANY";
        }

        return NULL;
}

const char *dns_type_to_string(uint16_t type) {

        switch (type) {

        case DNS_TYPE_A:
                return "A";

        case DNS_TYPE_NS:
                return "NS";

        case DNS_TYPE_CNAME:
                return "CNAME";

        case DNS_TYPE_SOA:
                return "SOA";

        case DNS_TYPE_PTR:
                return "PTR";

        case DNS_TYPE_HINFO:
                return "HINFO";

        case DNS_TYPE_MX:
                return "MX";

        case DNS_TYPE_TXT:
                return "TXT";

        case DNS_TYPE_AAAA:
                return "AAAA";

        case DNS_TYPE_SRV:
                return "SRV";

        case DNS_TYPE_SSHFP:
                return "SSHFP";

        case DNS_TYPE_DNAME:
                return "DNAME";

        case DNS_TYPE_ANY:
                return "ANY";

        case DNS_TYPE_OPT:
                return "OPT";

        case DNS_TYPE_TKEY:
                return "TKEY";

        case DNS_TYPE_TSIG:
                return "TSIG";

        case DNS_TYPE_IXFR:
                return "IXFR";

        case DNS_TYPE_AXFR:
                return "AXFR";
        }

        return NULL;
}