lib/dns/ssu.c

	ssu.c revision 6028d1ce0380d0ba7f6c6ecd1ad20b31ddd1becb
/*
 * Copyright (C) 2000  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

/*
 * $Id: ssu.c,v 1.10 2000/05/08 19:23:16 tale Exp $
 * Principal Author: Brian Wellington
 */

#include <config.h>

#include <isc/magic.h>
#include <isc/mem.h>
#include <isc/string.h>     /* Required for HP/UX (and others?) */
#include <isc/util.h>

#include <dns/name.h>
#include <dns/ssu.h>

#define SSUTABLEMAGIC       0x53535554 /* SSUT */
#define VALID_SSUTABLE(table)   ISC_MAGIC_VALID((table), SSUTABLEMAGIC)
#define SSURULEMAGIC        0x53535552 /* SSUR */
#define VALID_SSURULE(table)    ISC_MAGIC_VALID((table), SSURULEMAGIC)

struct dns_ssurule {
    isc_uint32_t magic;
    isc_boolean_t grant;    /* is this a grant or a deny? */
    unsigned int matchtype; /* which type of pattern match? */
    dns_name_t *identity;   /* the identity to match */
    dns_name_t *name;   /* the name being updated */
    unsigned int ntypes;    /* number of data types covered */
    dns_rdatatype_t *types; /* the data types.  Can include ANY, */
                /* defaults to all but SIG,SOA,NS if NULL*/
    ISC_LINK(dns_ssurule_t) link;
};

struct dns_ssutable {
    isc_uint32_t magic;
    isc_mem_t *mctx;
    unsigned int references;
    isc_mutex_t lock;
    ISC_LIST(dns_ssurule_t) rules;
};

isc_result_t
dns_ssutable_create(isc_mem_t *mctx, dns_ssutable_t **tablep) {
    isc_result_t result;
    dns_ssutable_t *table;

    REQUIRE(tablep != NULL && *tablep == NULL);
    REQUIRE(mctx != NULL);

    table = isc_mem_get(mctx, sizeof(dns_ssutable_t));
    if (table == NULL)
        return (ISC_R_NOMEMORY);
    result = isc_mutex_init(&table->lock);
    if (result != ISC_R_SUCCESS) {
        isc_mem_put(mctx, table, sizeof(dns_ssutable_t));
        return (result);
    }
    table->references = 1;
    table->mctx = mctx;
    ISC_LIST_INIT(table->rules);
    table->magic = SSUTABLEMAGIC;
    *tablep = table;
    return (ISC_R_SUCCESS);
}

static inline void
destroy(dns_ssutable_t *table) {
    isc_mem_t *mctx;

    REQUIRE(VALID_SSUTABLE(table));

    mctx = table->mctx;
    while (!ISC_LIST_EMPTY(table->rules)) {
        dns_ssurule_t *rule = ISC_LIST_HEAD(table->rules);
        if (rule->identity != NULL) {
            dns_name_free(rule->identity, mctx);
            isc_mem_put(mctx, rule->identity, sizeof(dns_name_t));
        }
        if (rule->name != NULL) {
            dns_name_free(rule->name, mctx);
            isc_mem_put(mctx, rule->name, sizeof(dns_name_t));
        }
        if (rule->types != NULL)
            isc_mem_put(mctx, rule->types,
                    rule->ntypes * sizeof(dns_rdatatype_t));
        ISC_LIST_UNLINK(table->rules, rule, link);
        rule->magic = 0;
        isc_mem_put(mctx, rule, sizeof(dns_ssurule_t));
    }
    isc_mutex_destroy(&table->lock);
    table->magic = 0;
    isc_mem_put(mctx, table, sizeof(dns_ssutable_t));
}

void
dns_ssutable_attach(dns_ssutable_t *source, dns_ssutable_t **targetp) {
    REQUIRE(VALID_SSUTABLE(source));
    REQUIRE(targetp != NULL && *targetp == NULL);

    LOCK(&source->lock);

    INSIST(source->references > 0);
    source->references++;
    INSIST(source->references != 0);

    UNLOCK(&source->lock);

    *targetp = source;
}

void
dns_ssutable_detach(dns_ssutable_t **tablep) {
    dns_ssutable_t *table;
    isc_boolean_t done = ISC_FALSE;

    REQUIRE(tablep != NULL);
    table = *tablep;
    REQUIRE(VALID_SSUTABLE(table));

    LOCK(&table->lock);

    INSIST(table->references > 0);
    if (--table->references == 0)
        done = ISC_TRUE;
    UNLOCK(&table->lock);

    *tablep = NULL;

    if (done)
        destroy(table);
}

isc_result_t
dns_ssutable_addrule(dns_ssutable_t *table, isc_boolean_t grant,
             dns_name_t *identity, unsigned int matchtype,
             dns_name_t *name, unsigned int ntypes,
             dns_rdatatype_t *types)
{
    dns_ssurule_t *rule;
    isc_mem_t *mctx;
    isc_result_t result;

    REQUIRE(VALID_SSUTABLE(table));
    REQUIRE(dns_name_isabsolute(identity));
    REQUIRE(dns_name_isabsolute(name));
    REQUIRE(matchtype <= DNS_SSUMATCHTYPE_SELF);
    if (matchtype == DNS_SSUMATCHTYPE_WILDCARD)
        REQUIRE(dns_name_iswildcard(name));
    if (ntypes > 0)
        REQUIRE(types != NULL);

    mctx = table->mctx;
    rule = isc_mem_get(mctx, sizeof(dns_ssurule_t));
    if (rule == NULL)
        return (ISC_R_NOMEMORY);

    rule->identity = NULL;
    rule->name = NULL;
    rule->types = NULL;

    rule->grant = grant;

    rule->identity = isc_mem_get(mctx, sizeof(dns_name_t));
    if (rule->identity == NULL) {
        result = ISC_R_NOMEMORY;
        goto failure;
    }
    dns_name_init(rule->identity, NULL);
    result = dns_name_dup(identity, mctx, rule->identity);
    if (result != ISC_R_SUCCESS)
        goto failure;

    rule->name = isc_mem_get(mctx, sizeof(dns_name_t));
    if (rule->name == NULL) {
        result = ISC_R_NOMEMORY;
        goto failure;
    }
    dns_name_init(rule->name, NULL);
    result = dns_name_dup(name, mctx, rule->name);
    if (result != ISC_R_SUCCESS)
        goto failure;

    rule->matchtype = matchtype;

    rule->ntypes = ntypes;
    if (ntypes > 0) {
        rule->types = isc_mem_get(mctx,
                      ntypes * sizeof(dns_rdatatype_t));
        if (rule->types == NULL) {
            result = ISC_R_NOMEMORY;
            goto failure;
        }
        memcpy(rule->types, types, ntypes * sizeof(dns_rdatatype_t));
    }
    else
        rule->types = NULL;

    rule->magic = SSURULEMAGIC;
    ISC_LIST_APPEND(table->rules, rule, link);

    return (ISC_R_SUCCESS);

 failure:
    if (rule->identity != NULL) {
        if (dns_name_dynamic(rule->identity))
            dns_name_free(rule->identity, mctx);
        isc_mem_put(mctx, rule->identity, sizeof(dns_name_t));
    }
    if (rule->name != NULL) {
        if (dns_name_dynamic(rule->name))
            dns_name_free(rule->name, mctx);
        isc_mem_put(mctx, rule->name, sizeof(dns_name_t));
    }
    if (rule->types != NULL)
        isc_mem_put(mctx, rule->types,
                ntypes * sizeof(dns_rdatatype_t));
    isc_mem_put(mctx, rule, sizeof(dns_ssurule_t));

    return (result);
}

static inline isc_boolean_t
isusertype(dns_rdatatype_t type) {
    return (type != dns_rdatatype_ns &&
        type != dns_rdatatype_soa &&
        type != dns_rdatatype_sig);
}

isc_boolean_t
dns_ssutable_checkrules(dns_ssutable_t *table, dns_name_t *signer,
            dns_name_t *name, dns_rdatatype_t type)
{
    dns_ssurule_t *rule;
    unsigned int i;

    REQUIRE(VALID_SSUTABLE(table));
    REQUIRE(signer == NULL || dns_name_isabsolute(signer));
    REQUIRE(dns_name_isabsolute(name));

    if (signer == NULL)
        return (ISC_FALSE);
    rule = ISC_LIST_HEAD(table->rules);
        rule = ISC_LIST_NEXT(rule, link);
    for (rule = ISC_LIST_HEAD(table->rules);
         rule != NULL;
         rule = ISC_LIST_NEXT(rule, link))
    {
        if (dns_name_iswildcard(rule->identity)) {
            if (!dns_name_matcheswildcard(signer, rule->identity))
                continue;
        }
        else {
            if (!dns_name_equal(signer, rule->identity))
                continue;
        }

        if (rule->matchtype == DNS_SSUMATCHTYPE_NAME) {
            if (!dns_name_equal(name, rule->name))
                continue;
        }
        else if (rule->matchtype == DNS_SSUMATCHTYPE_SUBDOMAIN) {
            if (!dns_name_issubdomain(name, rule->name))
                continue;
        }
        else if (rule->matchtype == DNS_SSUMATCHTYPE_WILDCARD) {
            if (!dns_name_matcheswildcard(name, rule->name))
                continue;

        }
        else if (rule->matchtype == DNS_SSUMATCHTYPE_SELF) {
            if (!dns_name_equal(signer, name))
                continue;
        }

        if (rule->ntypes == 0) {
            if (!isusertype(type))
                continue;
        }
        else {
            for (i = 0; i < rule->ntypes; i++) {
                if (rule->types[i] == dns_rdatatype_any ||
                    rule->types[i] == type)
                    break;
            }
            if (i == rule->ntypes)
                continue;
        }
        return (rule->grant);
    }

    return (ISC_FALSE);
}

isc_boolean_t
dns_ssurule_isgrant(const dns_ssurule_t *rule) {
    REQUIRE(VALID_SSURULE(rule));
    return (rule->grant);
}

dns_name_t *
dns_ssurule_identity(const dns_ssurule_t *rule) {
    REQUIRE(VALID_SSURULE(rule));
    return (rule->identity);
}

unsigned int
dns_ssurule_matchtype(const dns_ssurule_t *rule) {
    REQUIRE(VALID_SSURULE(rule));
    return (rule->matchtype);
}

dns_name_t *
dns_ssurule_name(const dns_ssurule_t *rule) {
    REQUIRE(VALID_SSURULE(rule));
    return (rule->name);
}

unsigned int
dns_ssurule_types(const dns_ssurule_t *rule, dns_rdatatype_t **types) {
    REQUIRE(VALID_SSURULE(rule));
    REQUIRE(types != NULL && *types != NULL);
    *types = rule->types;
    return (rule->ntypes);
}

isc_result_t
dns_ssutable_firstrule(const dns_ssutable_t *table, dns_ssurule_t **rule) {
    REQUIRE(VALID_SSUTABLE(table));
    REQUIRE(rule != NULL && *rule == NULL);
    *rule = ISC_LIST_HEAD(table->rules);
    return (*rule != NULL ? ISC_R_SUCCESS : ISC_R_NOMORE);
}

isc_result_t
dns_ssutable_nextrule(dns_ssurule_t *rule, dns_ssurule_t **nextrule) {
    REQUIRE(VALID_SSURULE(rule));
    REQUIRE(nextrule != NULL && *nextrule == NULL);
    *nextrule = ISC_LIST_NEXT(rule, link);
    return (*nextrule != NULL ? ISC_R_SUCCESS : ISC_R_NOMORE);
}