hmac_link.c

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/*
 * Portions Copyright (C) 2004-2014  Internet Systems Consortium, Inc. ("ISC")
 * Portions Copyright (C) 1999-2002  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and/or 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 ISC AND NETWORK ASSOCIATES DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC 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.
 *
 * Portions Copyright (C) 1995-2000 by Network Associates, Inc.
 *
 * Permission to use, copy, modify, and/or 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 ISC AND NETWORK ASSOCIATES DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC 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.
 */

/*
 * Principal Author: Brian Wellington
 * $Id: hmac_link.c,v 1.19 2011/01/11 23:47:13 tbox Exp $
 */

#include <config.h>

#include <isc/buffer.h>
#include <isc/hmacmd5.h>
#include <isc/hmacsha.h>
#include <isc/md5.h>
#include <isc/sha1.h>
#include <isc/mem.h>
#include <isc/safe.h>
#include <isc/string.h>
#include <isc/util.h>

#include <dst/result.h>

#include "dst_internal.h"
#include "dst_parse.h"

static isc_result_t hmacmd5_fromdns(dst_key_t *key, isc_buffer_t *data);

struct dst_hmacmd5_key {
        unsigned char key[ISC_MD5_BLOCK_LENGTH];
};

static isc_result_t
getkeybits(dst_key_t *key, struct dst_private_element *element) {

        if (element->length != 2)
                return (DST_R_INVALIDPRIVATEKEY);

        key->key_bits = (element->data[0] << 8) + element->data[1];

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacmd5_createctx(dst_key_t *key, dst_context_t *dctx) {
        isc_hmacmd5_t *hmacmd5ctx;
        dst_hmacmd5_key_t *hkey = key->keydata.hmacmd5;

        hmacmd5ctx = isc_mem_get(dctx->mctx, sizeof(isc_hmacmd5_t));
        if (hmacmd5ctx == NULL)
                return (ISC_R_NOMEMORY);
        isc_hmacmd5_init(hmacmd5ctx, hkey->key, ISC_SHA1_BLOCK_LENGTH);
        dctx->ctxdata.hmacmd5ctx = hmacmd5ctx;
        return (ISC_R_SUCCESS);
}

static void
hmacmd5_destroyctx(dst_context_t *dctx) {
        isc_hmacmd5_t *hmacmd5ctx = dctx->ctxdata.hmacmd5ctx;

        if (hmacmd5ctx != NULL) {
                isc_hmacmd5_invalidate(hmacmd5ctx);
                isc_mem_put(dctx->mctx, hmacmd5ctx, sizeof(isc_hmacmd5_t));
                dctx->ctxdata.hmacmd5ctx = NULL;
        }
}

static isc_result_t
hmacmd5_adddata(dst_context_t *dctx, const isc_region_t *data) {
        isc_hmacmd5_t *hmacmd5ctx = dctx->ctxdata.hmacmd5ctx;

        isc_hmacmd5_update(hmacmd5ctx, data->base, data->length);
        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacmd5_sign(dst_context_t *dctx, isc_buffer_t *sig) {
        isc_hmacmd5_t *hmacmd5ctx = dctx->ctxdata.hmacmd5ctx;
        unsigned char *digest;

        if (isc_buffer_availablelength(sig) < ISC_MD5_DIGESTLENGTH)
                return (ISC_R_NOSPACE);
        digest = isc_buffer_used(sig);
        isc_hmacmd5_sign(hmacmd5ctx, digest);
        isc_buffer_add(sig, ISC_MD5_DIGESTLENGTH);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacmd5_verify(dst_context_t *dctx, const isc_region_t *sig) {
        isc_hmacmd5_t *hmacmd5ctx = dctx->ctxdata.hmacmd5ctx;

        if (sig->length > ISC_MD5_DIGESTLENGTH)
                return (DST_R_VERIFYFAILURE);

        if (isc_hmacmd5_verify2(hmacmd5ctx, sig->base, sig->length))
                return (ISC_R_SUCCESS);
        else
                return (DST_R_VERIFYFAILURE);
}

static isc_boolean_t
hmacmd5_compare(const dst_key_t *key1, const dst_key_t *key2) {
        dst_hmacmd5_key_t *hkey1, *hkey2;

        hkey1 = key1->keydata.hmacmd5;
        hkey2 = key2->keydata.hmacmd5;

        if (hkey1 == NULL && hkey2 == NULL)
                return (ISC_TRUE);
        else if (hkey1 == NULL || hkey2 == NULL)
                return (ISC_FALSE);

        if (isc_safe_memcmp(hkey1->key, hkey2->key, ISC_SHA1_BLOCK_LENGTH))
                return (ISC_TRUE);
        else
                return (ISC_FALSE);
}

static isc_result_t
hmacmd5_generate(dst_key_t *key, int pseudorandom_ok, void (*callback)(int)) {
        isc_buffer_t b;
        isc_result_t ret;
        unsigned int bytes;
        unsigned char data[ISC_SHA1_BLOCK_LENGTH];

        UNUSED(callback);

        bytes = (key->key_size + 7) / 8;
        if (bytes > ISC_SHA1_BLOCK_LENGTH) {
                bytes = ISC_SHA1_BLOCK_LENGTH;
                key->key_size = ISC_SHA1_BLOCK_LENGTH * 8;
        }

        memset(data, 0, ISC_SHA1_BLOCK_LENGTH);
        ret = dst__entropy_getdata(data, bytes, ISC_TF(pseudorandom_ok != 0));

        if (ret != ISC_R_SUCCESS)
                return (ret);

        isc_buffer_init(&b, data, bytes);
        isc_buffer_add(&b, bytes);
        ret = hmacmd5_fromdns(key, &b);
        memset(data, 0, ISC_SHA1_BLOCK_LENGTH);

        return (ret);
}

static isc_boolean_t
hmacmd5_isprivate(const dst_key_t *key) {
        UNUSED(key);
        return (ISC_TRUE);
}

static void
hmacmd5_destroy(dst_key_t *key) {
        dst_hmacmd5_key_t *hkey = key->keydata.hmacmd5;

        memset(hkey, 0, sizeof(dst_hmacmd5_key_t));
        isc_mem_put(key->mctx, hkey, sizeof(dst_hmacmd5_key_t));
        key->keydata.hmacmd5 = NULL;
}

static isc_result_t
hmacmd5_todns(const dst_key_t *key, isc_buffer_t *data) {
        dst_hmacmd5_key_t *hkey;
        unsigned int bytes;

        REQUIRE(key->keydata.hmacmd5 != NULL);

        hkey = key->keydata.hmacmd5;

        bytes = (key->key_size + 7) / 8;
        if (isc_buffer_availablelength(data) < bytes)
                return (ISC_R_NOSPACE);
        isc_buffer_putmem(data, hkey->key, bytes);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacmd5_fromdns(dst_key_t *key, isc_buffer_t *data) {
        dst_hmacmd5_key_t *hkey;
        int keylen;
        isc_region_t r;
        isc_md5_t md5ctx;

        isc_buffer_remainingregion(data, &r);
        if (r.length == 0)
                return (ISC_R_SUCCESS);

        hkey = isc_mem_get(key->mctx, sizeof(dst_hmacmd5_key_t));
        if (hkey == NULL)
                return (ISC_R_NOMEMORY);

        memset(hkey->key, 0, sizeof(hkey->key));

        if (r.length > ISC_SHA1_BLOCK_LENGTH) {
                isc_md5_init(&md5ctx);
                isc_md5_update(&md5ctx, r.base, r.length);
                isc_md5_final(&md5ctx, hkey->key);
                keylen = ISC_MD5_DIGESTLENGTH;
        } else {
                memmove(hkey->key, r.base, r.length);
                keylen = r.length;
        }

        key->key_size = keylen * 8;
        key->keydata.hmacmd5 = hkey;

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacmd5_tofile(const dst_key_t *key, const char *directory) {
        int cnt = 0;
        dst_hmacmd5_key_t *hkey;
        dst_private_t priv;
        int bytes = (key->key_size + 7) / 8;
        unsigned char buf[2];

        if (key->keydata.hmacmd5 == NULL)
                return (DST_R_NULLKEY);

        if (key->external)
                return (DST_R_EXTERNALKEY);

        hkey = key->keydata.hmacmd5;

        priv.elements[cnt].tag = TAG_HMACMD5_KEY;
        priv.elements[cnt].length = bytes;
        priv.elements[cnt++].data = hkey->key;

        buf[0] = (key->key_bits >> 8) & 0xffU;
        buf[1] = key->key_bits & 0xffU;
        priv.elements[cnt].tag = TAG_HMACMD5_BITS;
        priv.elements[cnt].data = buf;
        priv.elements[cnt++].length = 2;

        priv.nelements = cnt;
        return (dst__privstruct_writefile(key, &priv, directory));
}

static isc_result_t
hmacmd5_parse(dst_key_t *key, isc_lex_t *lexer, dst_key_t *pub) {
        dst_private_t priv;
        isc_result_t result, tresult;
        isc_buffer_t b;
        isc_mem_t *mctx = key->mctx;
        unsigned int i;

        UNUSED(pub);
        /* read private key file */
        result = dst__privstruct_parse(key, DST_ALG_HMACMD5, lexer, mctx,
                                       &priv);
        if (result != ISC_R_SUCCESS)
                return (result);

        if (key->external)
                result = DST_R_EXTERNALKEY;

        key->key_bits = 0;
        for (i = 0; i < priv.nelements && result == ISC_R_SUCCESS; i++) {
                switch (priv.elements[i].tag) {
                case TAG_HMACMD5_KEY:
                        isc_buffer_init(&b, priv.elements[i].data,
                                        priv.elements[i].length);
                        isc_buffer_add(&b, priv.elements[i].length);
                        tresult = hmacmd5_fromdns(key, &b);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                case TAG_HMACMD5_BITS:
                        tresult = getkeybits(key, &priv.elements[i]);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                default:
                        result = DST_R_INVALIDPRIVATEKEY;
                        break;
                }
        }
        dst__privstruct_free(&priv, mctx);
        memset(&priv, 0, sizeof(priv));
        return (result);
}

static dst_func_t hmacmd5_functions = {
        hmacmd5_createctx,
        NULL, /*%< createctx2 */
        hmacmd5_destroyctx,
        hmacmd5_adddata,
        hmacmd5_sign,
        hmacmd5_verify,
        NULL, /*%< verify2 */
        NULL, /*%< computesecret */
        hmacmd5_compare,
        NULL, /*%< paramcompare */
        hmacmd5_generate,
        hmacmd5_isprivate,
        hmacmd5_destroy,
        hmacmd5_todns,
        hmacmd5_fromdns,
        hmacmd5_tofile,
        hmacmd5_parse,
        NULL, /*%< cleanup */
        NULL, /*%< fromlabel */
        NULL, /*%< dump */
        NULL, /*%< restore */
};

isc_result_t
dst__hmacmd5_init(dst_func_t **funcp) {
        REQUIRE(funcp != NULL);
        if (*funcp == NULL)
                *funcp = &hmacmd5_functions;
        return (ISC_R_SUCCESS);
}

static isc_result_t hmacsha1_fromdns(dst_key_t *key, isc_buffer_t *data);

struct dst_hmacsha1_key {
        unsigned char key[ISC_SHA1_BLOCK_LENGTH];
};

static isc_result_t
hmacsha1_createctx(dst_key_t *key, dst_context_t *dctx) {
        isc_hmacsha1_t *hmacsha1ctx;
        dst_hmacsha1_key_t *hkey = key->keydata.hmacsha1;

        hmacsha1ctx = isc_mem_get(dctx->mctx, sizeof(isc_hmacsha1_t));
        if (hmacsha1ctx == NULL)
                return (ISC_R_NOMEMORY);
        isc_hmacsha1_init(hmacsha1ctx, hkey->key, ISC_SHA1_BLOCK_LENGTH);
        dctx->ctxdata.hmacsha1ctx = hmacsha1ctx;
        return (ISC_R_SUCCESS);
}

static void
hmacsha1_destroyctx(dst_context_t *dctx) {
        isc_hmacsha1_t *hmacsha1ctx = dctx->ctxdata.hmacsha1ctx;

        if (hmacsha1ctx != NULL) {
                isc_hmacsha1_invalidate(hmacsha1ctx);
                isc_mem_put(dctx->mctx, hmacsha1ctx, sizeof(isc_hmacsha1_t));
                dctx->ctxdata.hmacsha1ctx = NULL;
        }
}

static isc_result_t
hmacsha1_adddata(dst_context_t *dctx, const isc_region_t *data) {
        isc_hmacsha1_t *hmacsha1ctx = dctx->ctxdata.hmacsha1ctx;

        isc_hmacsha1_update(hmacsha1ctx, data->base, data->length);
        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha1_sign(dst_context_t *dctx, isc_buffer_t *sig) {
        isc_hmacsha1_t *hmacsha1ctx = dctx->ctxdata.hmacsha1ctx;
        unsigned char *digest;

        if (isc_buffer_availablelength(sig) < ISC_SHA1_DIGESTLENGTH)
                return (ISC_R_NOSPACE);
        digest = isc_buffer_used(sig);
        isc_hmacsha1_sign(hmacsha1ctx, digest, ISC_SHA1_DIGESTLENGTH);
        isc_buffer_add(sig, ISC_SHA1_DIGESTLENGTH);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha1_verify(dst_context_t *dctx, const isc_region_t *sig) {
        isc_hmacsha1_t *hmacsha1ctx = dctx->ctxdata.hmacsha1ctx;

        if (sig->length > ISC_SHA1_DIGESTLENGTH || sig->length == 0)
                return (DST_R_VERIFYFAILURE);

        if (isc_hmacsha1_verify(hmacsha1ctx, sig->base, sig->length))
                return (ISC_R_SUCCESS);
        else
                return (DST_R_VERIFYFAILURE);
}

static isc_boolean_t
hmacsha1_compare(const dst_key_t *key1, const dst_key_t *key2) {
        dst_hmacsha1_key_t *hkey1, *hkey2;

        hkey1 = key1->keydata.hmacsha1;
        hkey2 = key2->keydata.hmacsha1;

        if (hkey1 == NULL && hkey2 == NULL)
                return (ISC_TRUE);
        else if (hkey1 == NULL || hkey2 == NULL)
                return (ISC_FALSE);

        if (isc_safe_memcmp(hkey1->key, hkey2->key, ISC_SHA1_BLOCK_LENGTH))
                return (ISC_TRUE);
        else
                return (ISC_FALSE);
}

static isc_result_t
hmacsha1_generate(dst_key_t *key, int pseudorandom_ok, void (*callback)(int)) {
        isc_buffer_t b;
        isc_result_t ret;
        unsigned int bytes;
        unsigned char data[ISC_SHA1_BLOCK_LENGTH];

        UNUSED(callback);

        bytes = (key->key_size + 7) / 8;
        if (bytes > ISC_SHA1_BLOCK_LENGTH) {
                bytes = ISC_SHA1_BLOCK_LENGTH;
                key->key_size = ISC_SHA1_BLOCK_LENGTH * 8;
        }

        memset(data, 0, ISC_SHA1_BLOCK_LENGTH);
        ret = dst__entropy_getdata(data, bytes, ISC_TF(pseudorandom_ok != 0));

        if (ret != ISC_R_SUCCESS)
                return (ret);

        isc_buffer_init(&b, data, bytes);
        isc_buffer_add(&b, bytes);
        ret = hmacsha1_fromdns(key, &b);
        memset(data, 0, ISC_SHA1_BLOCK_LENGTH);

        return (ret);
}

static isc_boolean_t
hmacsha1_isprivate(const dst_key_t *key) {
        UNUSED(key);
        return (ISC_TRUE);
}

static void
hmacsha1_destroy(dst_key_t *key) {
        dst_hmacsha1_key_t *hkey = key->keydata.hmacsha1;

        memset(hkey, 0, sizeof(dst_hmacsha1_key_t));
        isc_mem_put(key->mctx, hkey, sizeof(dst_hmacsha1_key_t));
        key->keydata.hmacsha1 = NULL;
}

static isc_result_t
hmacsha1_todns(const dst_key_t *key, isc_buffer_t *data) {
        dst_hmacsha1_key_t *hkey;
        unsigned int bytes;

        REQUIRE(key->keydata.hmacsha1 != NULL);

        hkey = key->keydata.hmacsha1;

        bytes = (key->key_size + 7) / 8;
        if (isc_buffer_availablelength(data) < bytes)
                return (ISC_R_NOSPACE);
        isc_buffer_putmem(data, hkey->key, bytes);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha1_fromdns(dst_key_t *key, isc_buffer_t *data) {
        dst_hmacsha1_key_t *hkey;
        int keylen;
        isc_region_t r;
        isc_sha1_t sha1ctx;

        isc_buffer_remainingregion(data, &r);
        if (r.length == 0)
                return (ISC_R_SUCCESS);

        hkey = isc_mem_get(key->mctx, sizeof(dst_hmacsha1_key_t));
        if (hkey == NULL)
                return (ISC_R_NOMEMORY);

        memset(hkey->key, 0, sizeof(hkey->key));

        if (r.length > ISC_SHA1_BLOCK_LENGTH) {
                isc_sha1_init(&sha1ctx);
                isc_sha1_update(&sha1ctx, r.base, r.length);
                isc_sha1_final(&sha1ctx, hkey->key);
                keylen = ISC_SHA1_DIGESTLENGTH;
        } else {
                memmove(hkey->key, r.base, r.length);
                keylen = r.length;
        }

        key->key_size = keylen * 8;
        key->keydata.hmacsha1 = hkey;

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha1_tofile(const dst_key_t *key, const char *directory) {
        int cnt = 0;
        dst_hmacsha1_key_t *hkey;
        dst_private_t priv;
        int bytes = (key->key_size + 7) / 8;
        unsigned char buf[2];

        if (key->keydata.hmacsha1 == NULL)
                return (DST_R_NULLKEY);

        if (key->external)
                return (DST_R_EXTERNALKEY);

        hkey = key->keydata.hmacsha1;

        priv.elements[cnt].tag = TAG_HMACSHA1_KEY;
        priv.elements[cnt].length = bytes;
        priv.elements[cnt++].data = hkey->key;

        buf[0] = (key->key_bits >> 8) & 0xffU;
        buf[1] = key->key_bits & 0xffU;
        priv.elements[cnt].tag = TAG_HMACSHA1_BITS;
        priv.elements[cnt].data = buf;
        priv.elements[cnt++].length = 2;

        priv.nelements = cnt;
        return (dst__privstruct_writefile(key, &priv, directory));
}

static isc_result_t
hmacsha1_parse(dst_key_t *key, isc_lex_t *lexer, dst_key_t *pub) {
        dst_private_t priv;
        isc_result_t result, tresult;
        isc_buffer_t b;
        isc_mem_t *mctx = key->mctx;
        unsigned int i;

        UNUSED(pub);
        /* read private key file */
        result = dst__privstruct_parse(key, DST_ALG_HMACSHA1, lexer, mctx,
                                       &priv);
        if (result != ISC_R_SUCCESS)
                return (result);

        if (key->external)
                result = DST_R_EXTERNALKEY;

        key->key_bits = 0;
        for (i = 0; i < priv.nelements && result == ISC_R_SUCCESS; i++) {
                switch (priv.elements[i].tag) {
                case TAG_HMACSHA1_KEY:
                        isc_buffer_init(&b, priv.elements[i].data,
                                        priv.elements[i].length);
                        isc_buffer_add(&b, priv.elements[i].length);
                        tresult = hmacsha1_fromdns(key, &b);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                case TAG_HMACSHA1_BITS:
                        tresult = getkeybits(key, &priv.elements[i]);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                default:
                        result = DST_R_INVALIDPRIVATEKEY;
                        break;
                }
        }
        dst__privstruct_free(&priv, mctx);
        memset(&priv, 0, sizeof(priv));
        return (result);
}

static dst_func_t hmacsha1_functions = {
        hmacsha1_createctx,
        NULL, /*%< createctx2 */
        hmacsha1_destroyctx,
        hmacsha1_adddata,
        hmacsha1_sign,
        hmacsha1_verify,
        NULL, /* verify2 */
        NULL, /* computesecret */
        hmacsha1_compare,
        NULL, /* paramcompare */
        hmacsha1_generate,
        hmacsha1_isprivate,
        hmacsha1_destroy,
        hmacsha1_todns,
        hmacsha1_fromdns,
        hmacsha1_tofile,
        hmacsha1_parse,
        NULL, /* cleanup */
        NULL, /* fromlabel */
        NULL, /* dump */
        NULL, /* restore */
};

isc_result_t
dst__hmacsha1_init(dst_func_t **funcp) {
        REQUIRE(funcp != NULL);
        if (*funcp == NULL)
                *funcp = &hmacsha1_functions;
        return (ISC_R_SUCCESS);
}

static isc_result_t hmacsha224_fromdns(dst_key_t *key, isc_buffer_t *data);

struct dst_hmacsha224_key {
        unsigned char key[ISC_SHA224_BLOCK_LENGTH];
};

static isc_result_t
hmacsha224_createctx(dst_key_t *key, dst_context_t *dctx) {
        isc_hmacsha224_t *hmacsha224ctx;
        dst_hmacsha224_key_t *hkey = key->keydata.hmacsha224;

        hmacsha224ctx = isc_mem_get(dctx->mctx, sizeof(isc_hmacsha224_t));
        if (hmacsha224ctx == NULL)
                return (ISC_R_NOMEMORY);
        isc_hmacsha224_init(hmacsha224ctx, hkey->key, ISC_SHA224_BLOCK_LENGTH);
        dctx->ctxdata.hmacsha224ctx = hmacsha224ctx;
        return (ISC_R_SUCCESS);
}

static void
hmacsha224_destroyctx(dst_context_t *dctx) {
        isc_hmacsha224_t *hmacsha224ctx = dctx->ctxdata.hmacsha224ctx;

        if (hmacsha224ctx != NULL) {
                isc_hmacsha224_invalidate(hmacsha224ctx);
                isc_mem_put(dctx->mctx, hmacsha224ctx, sizeof(isc_hmacsha224_t));
                dctx->ctxdata.hmacsha224ctx = NULL;
        }
}

static isc_result_t
hmacsha224_adddata(dst_context_t *dctx, const isc_region_t *data) {
        isc_hmacsha224_t *hmacsha224ctx = dctx->ctxdata.hmacsha224ctx;

        isc_hmacsha224_update(hmacsha224ctx, data->base, data->length);
        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha224_sign(dst_context_t *dctx, isc_buffer_t *sig) {
        isc_hmacsha224_t *hmacsha224ctx = dctx->ctxdata.hmacsha224ctx;
        unsigned char *digest;

        if (isc_buffer_availablelength(sig) < ISC_SHA224_DIGESTLENGTH)
                return (ISC_R_NOSPACE);
        digest = isc_buffer_used(sig);
        isc_hmacsha224_sign(hmacsha224ctx, digest, ISC_SHA224_DIGESTLENGTH);
        isc_buffer_add(sig, ISC_SHA224_DIGESTLENGTH);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha224_verify(dst_context_t *dctx, const isc_region_t *sig) {
        isc_hmacsha224_t *hmacsha224ctx = dctx->ctxdata.hmacsha224ctx;

        if (sig->length > ISC_SHA224_DIGESTLENGTH || sig->length == 0)
                return (DST_R_VERIFYFAILURE);

        if (isc_hmacsha224_verify(hmacsha224ctx, sig->base, sig->length))
                return (ISC_R_SUCCESS);
        else
                return (DST_R_VERIFYFAILURE);
}

static isc_boolean_t
hmacsha224_compare(const dst_key_t *key1, const dst_key_t *key2) {
        dst_hmacsha224_key_t *hkey1, *hkey2;

        hkey1 = key1->keydata.hmacsha224;
        hkey2 = key2->keydata.hmacsha224;

        if (hkey1 == NULL && hkey2 == NULL)
                return (ISC_TRUE);
        else if (hkey1 == NULL || hkey2 == NULL)
                return (ISC_FALSE);

        if (isc_safe_memcmp(hkey1->key, hkey2->key, ISC_SHA224_BLOCK_LENGTH))
                return (ISC_TRUE);
        else
                return (ISC_FALSE);
}

static isc_result_t
hmacsha224_generate(dst_key_t *key, int pseudorandom_ok,
                    void (*callback)(int))
{
        isc_buffer_t b;
        isc_result_t ret;
        unsigned int bytes;
        unsigned char data[ISC_SHA224_BLOCK_LENGTH];

        UNUSED(callback);

        bytes = (key->key_size + 7) / 8;
        if (bytes > ISC_SHA224_BLOCK_LENGTH) {
                bytes = ISC_SHA224_BLOCK_LENGTH;
                key->key_size = ISC_SHA224_BLOCK_LENGTH * 8;
        }

        memset(data, 0, ISC_SHA224_BLOCK_LENGTH);
        ret = dst__entropy_getdata(data, bytes, ISC_TF(pseudorandom_ok != 0));

        if (ret != ISC_R_SUCCESS)
                return (ret);

        isc_buffer_init(&b, data, bytes);
        isc_buffer_add(&b, bytes);
        ret = hmacsha224_fromdns(key, &b);
        memset(data, 0, ISC_SHA224_BLOCK_LENGTH);

        return (ret);
}

static isc_boolean_t
hmacsha224_isprivate(const dst_key_t *key) {
        UNUSED(key);
        return (ISC_TRUE);
}

static void
hmacsha224_destroy(dst_key_t *key) {
        dst_hmacsha224_key_t *hkey = key->keydata.hmacsha224;

        memset(hkey, 0, sizeof(dst_hmacsha224_key_t));
        isc_mem_put(key->mctx, hkey, sizeof(dst_hmacsha224_key_t));
        key->keydata.hmacsha224 = NULL;
}

static isc_result_t
hmacsha224_todns(const dst_key_t *key, isc_buffer_t *data) {
        dst_hmacsha224_key_t *hkey;
        unsigned int bytes;

        REQUIRE(key->keydata.hmacsha224 != NULL);

        hkey = key->keydata.hmacsha224;

        bytes = (key->key_size + 7) / 8;
        if (isc_buffer_availablelength(data) < bytes)
                return (ISC_R_NOSPACE);
        isc_buffer_putmem(data, hkey->key, bytes);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha224_fromdns(dst_key_t *key, isc_buffer_t *data) {
        dst_hmacsha224_key_t *hkey;
        int keylen;
        isc_region_t r;
        isc_sha224_t sha224ctx;

        isc_buffer_remainingregion(data, &r);
        if (r.length == 0)
                return (ISC_R_SUCCESS);

        hkey = isc_mem_get(key->mctx, sizeof(dst_hmacsha224_key_t));
        if (hkey == NULL)
                return (ISC_R_NOMEMORY);

        memset(hkey->key, 0, sizeof(hkey->key));

        if (r.length > ISC_SHA224_BLOCK_LENGTH) {
                isc_sha224_init(&sha224ctx);
                isc_sha224_update(&sha224ctx, r.base, r.length);
                isc_sha224_final(hkey->key, &sha224ctx);
                keylen = ISC_SHA224_DIGESTLENGTH;
        } else {
                memmove(hkey->key, r.base, r.length);
                keylen = r.length;
        }

        key->key_size = keylen * 8;
        key->keydata.hmacsha224 = hkey;

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha224_tofile(const dst_key_t *key, const char *directory) {
        int cnt = 0;
        dst_hmacsha224_key_t *hkey;
        dst_private_t priv;
        int bytes = (key->key_size + 7) / 8;
        unsigned char buf[2];

        if (key->keydata.hmacsha224 == NULL)
                return (DST_R_NULLKEY);

        if (key->external)
                return (DST_R_EXTERNALKEY);

        hkey = key->keydata.hmacsha224;

        priv.elements[cnt].tag = TAG_HMACSHA224_KEY;
        priv.elements[cnt].length = bytes;
        priv.elements[cnt++].data = hkey->key;

        buf[0] = (key->key_bits >> 8) & 0xffU;
        buf[1] = key->key_bits & 0xffU;
        priv.elements[cnt].tag = TAG_HMACSHA224_BITS;
        priv.elements[cnt].data = buf;
        priv.elements[cnt++].length = 2;

        priv.nelements = cnt;
        return (dst__privstruct_writefile(key, &priv, directory));
}

static isc_result_t
hmacsha224_parse(dst_key_t *key, isc_lex_t *lexer, dst_key_t *pub) {
        dst_private_t priv;
        isc_result_t result, tresult;
        isc_buffer_t b;
        isc_mem_t *mctx = key->mctx;
        unsigned int i;

        UNUSED(pub);
        /* read private key file */
        result = dst__privstruct_parse(key, DST_ALG_HMACSHA224, lexer, mctx,
                                       &priv);
        if (result != ISC_R_SUCCESS)
                return (result);

        if (key->external)
                result = DST_R_EXTERNALKEY;

        key->key_bits = 0;
        for (i = 0; i < priv.nelements && result == ISC_R_SUCCESS; i++) {
                switch (priv.elements[i].tag) {
                case TAG_HMACSHA224_KEY:
                        isc_buffer_init(&b, priv.elements[i].data,
                                        priv.elements[i].length);
                        isc_buffer_add(&b, priv.elements[i].length);
                        tresult = hmacsha224_fromdns(key, &b);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                case TAG_HMACSHA224_BITS:
                        tresult = getkeybits(key, &priv.elements[i]);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                default:
                        result = DST_R_INVALIDPRIVATEKEY;
                        break;
                }
        }
        dst__privstruct_free(&priv, mctx);
        memset(&priv, 0, sizeof(priv));
        return (result);
}

static dst_func_t hmacsha224_functions = {
        hmacsha224_createctx,
        NULL, /*%< createctx2 */
        hmacsha224_destroyctx,
        hmacsha224_adddata,
        hmacsha224_sign,
        hmacsha224_verify,
        NULL, /* verify2 */
        NULL, /* computesecret */
        hmacsha224_compare,
        NULL, /* paramcompare */
        hmacsha224_generate,
        hmacsha224_isprivate,
        hmacsha224_destroy,
        hmacsha224_todns,
        hmacsha224_fromdns,
        hmacsha224_tofile,
        hmacsha224_parse,
        NULL, /* cleanup */
        NULL, /* fromlabel */
        NULL, /* dump */
        NULL, /* restore */
};

isc_result_t
dst__hmacsha224_init(dst_func_t **funcp) {
        REQUIRE(funcp != NULL);
        if (*funcp == NULL)
                *funcp = &hmacsha224_functions;
        return (ISC_R_SUCCESS);
}

static isc_result_t hmacsha256_fromdns(dst_key_t *key, isc_buffer_t *data);

struct dst_hmacsha256_key {
        unsigned char key[ISC_SHA256_BLOCK_LENGTH];
};

static isc_result_t
hmacsha256_createctx(dst_key_t *key, dst_context_t *dctx) {
        isc_hmacsha256_t *hmacsha256ctx;
        dst_hmacsha256_key_t *hkey = key->keydata.hmacsha256;

        hmacsha256ctx = isc_mem_get(dctx->mctx, sizeof(isc_hmacsha256_t));
        if (hmacsha256ctx == NULL)
                return (ISC_R_NOMEMORY);
        isc_hmacsha256_init(hmacsha256ctx, hkey->key, ISC_SHA256_BLOCK_LENGTH);
        dctx->ctxdata.hmacsha256ctx = hmacsha256ctx;
        return (ISC_R_SUCCESS);
}

static void
hmacsha256_destroyctx(dst_context_t *dctx) {
        isc_hmacsha256_t *hmacsha256ctx = dctx->ctxdata.hmacsha256ctx;

        if (hmacsha256ctx != NULL) {
                isc_hmacsha256_invalidate(hmacsha256ctx);
                isc_mem_put(dctx->mctx, hmacsha256ctx, sizeof(isc_hmacsha256_t));
                dctx->ctxdata.hmacsha256ctx = NULL;
        }
}

static isc_result_t
hmacsha256_adddata(dst_context_t *dctx, const isc_region_t *data) {
        isc_hmacsha256_t *hmacsha256ctx = dctx->ctxdata.hmacsha256ctx;

        isc_hmacsha256_update(hmacsha256ctx, data->base, data->length);
        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha256_sign(dst_context_t *dctx, isc_buffer_t *sig) {
        isc_hmacsha256_t *hmacsha256ctx = dctx->ctxdata.hmacsha256ctx;
        unsigned char *digest;

        if (isc_buffer_availablelength(sig) < ISC_SHA256_DIGESTLENGTH)
                return (ISC_R_NOSPACE);
        digest = isc_buffer_used(sig);
        isc_hmacsha256_sign(hmacsha256ctx, digest, ISC_SHA256_DIGESTLENGTH);
        isc_buffer_add(sig, ISC_SHA256_DIGESTLENGTH);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha256_verify(dst_context_t *dctx, const isc_region_t *sig) {
        isc_hmacsha256_t *hmacsha256ctx = dctx->ctxdata.hmacsha256ctx;

        if (sig->length > ISC_SHA256_DIGESTLENGTH || sig->length == 0)
                return (DST_R_VERIFYFAILURE);

        if (isc_hmacsha256_verify(hmacsha256ctx, sig->base, sig->length))
                return (ISC_R_SUCCESS);
        else
                return (DST_R_VERIFYFAILURE);
}

static isc_boolean_t
hmacsha256_compare(const dst_key_t *key1, const dst_key_t *key2) {
        dst_hmacsha256_key_t *hkey1, *hkey2;

        hkey1 = key1->keydata.hmacsha256;
        hkey2 = key2->keydata.hmacsha256;

        if (hkey1 == NULL && hkey2 == NULL)
                return (ISC_TRUE);
        else if (hkey1 == NULL || hkey2 == NULL)
                return (ISC_FALSE);

        if (isc_safe_memcmp(hkey1->key, hkey2->key, ISC_SHA256_BLOCK_LENGTH))
                return (ISC_TRUE);
        else
                return (ISC_FALSE);
}

static isc_result_t
hmacsha256_generate(dst_key_t *key, int pseudorandom_ok,
                    void (*callback)(int))
{
        isc_buffer_t b;
        isc_result_t ret;
        unsigned int bytes;
        unsigned char data[ISC_SHA256_BLOCK_LENGTH];

        UNUSED(callback);

        bytes = (key->key_size + 7) / 8;
        if (bytes > ISC_SHA256_BLOCK_LENGTH) {
                bytes = ISC_SHA256_BLOCK_LENGTH;
                key->key_size = ISC_SHA256_BLOCK_LENGTH * 8;
        }

        memset(data, 0, ISC_SHA256_BLOCK_LENGTH);
        ret = dst__entropy_getdata(data, bytes, ISC_TF(pseudorandom_ok != 0));

        if (ret != ISC_R_SUCCESS)
                return (ret);

        isc_buffer_init(&b, data, bytes);
        isc_buffer_add(&b, bytes);
        ret = hmacsha256_fromdns(key, &b);
        memset(data, 0, ISC_SHA256_BLOCK_LENGTH);

        return (ret);
}

static isc_boolean_t
hmacsha256_isprivate(const dst_key_t *key) {
        UNUSED(key);
        return (ISC_TRUE);
}

static void
hmacsha256_destroy(dst_key_t *key) {
        dst_hmacsha256_key_t *hkey = key->keydata.hmacsha256;

        memset(hkey, 0, sizeof(dst_hmacsha256_key_t));
        isc_mem_put(key->mctx, hkey, sizeof(dst_hmacsha256_key_t));
        key->keydata.hmacsha256 = NULL;
}

static isc_result_t
hmacsha256_todns(const dst_key_t *key, isc_buffer_t *data) {
        dst_hmacsha256_key_t *hkey;
        unsigned int bytes;

        REQUIRE(key->keydata.hmacsha256 != NULL);

        hkey = key->keydata.hmacsha256;

        bytes = (key->key_size + 7) / 8;
        if (isc_buffer_availablelength(data) < bytes)
                return (ISC_R_NOSPACE);
        isc_buffer_putmem(data, hkey->key, bytes);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha256_fromdns(dst_key_t *key, isc_buffer_t *data) {
        dst_hmacsha256_key_t *hkey;
        int keylen;
        isc_region_t r;
        isc_sha256_t sha256ctx;

        isc_buffer_remainingregion(data, &r);
        if (r.length == 0)
                return (ISC_R_SUCCESS);

        hkey = isc_mem_get(key->mctx, sizeof(dst_hmacsha256_key_t));
        if (hkey == NULL)
                return (ISC_R_NOMEMORY);

        memset(hkey->key, 0, sizeof(hkey->key));

        if (r.length > ISC_SHA256_BLOCK_LENGTH) {
                isc_sha256_init(&sha256ctx);
                isc_sha256_update(&sha256ctx, r.base, r.length);
                isc_sha256_final(hkey->key, &sha256ctx);
                keylen = ISC_SHA256_DIGESTLENGTH;
        } else {
                memmove(hkey->key, r.base, r.length);
                keylen = r.length;
        }

        key->key_size = keylen * 8;
        key->keydata.hmacsha256 = hkey;

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha256_tofile(const dst_key_t *key, const char *directory) {
        int cnt = 0;
        dst_hmacsha256_key_t *hkey;
        dst_private_t priv;
        int bytes = (key->key_size + 7) / 8;
        unsigned char buf[2];

        if (key->keydata.hmacsha256 == NULL)
                return (DST_R_NULLKEY);

        if (key->external)
                return (DST_R_EXTERNALKEY);

        hkey = key->keydata.hmacsha256;

        priv.elements[cnt].tag = TAG_HMACSHA256_KEY;
        priv.elements[cnt].length = bytes;
        priv.elements[cnt++].data = hkey->key;

        buf[0] = (key->key_bits >> 8) & 0xffU;
        buf[1] = key->key_bits & 0xffU;
        priv.elements[cnt].tag = TAG_HMACSHA256_BITS;
        priv.elements[cnt].data = buf;
        priv.elements[cnt++].length = 2;

        priv.nelements = cnt;
        return (dst__privstruct_writefile(key, &priv, directory));
}

static isc_result_t
hmacsha256_parse(dst_key_t *key, isc_lex_t *lexer, dst_key_t *pub) {
        dst_private_t priv;
        isc_result_t result, tresult;
        isc_buffer_t b;
        isc_mem_t *mctx = key->mctx;
        unsigned int i;

        UNUSED(pub);
        /* read private key file */
        result = dst__privstruct_parse(key, DST_ALG_HMACSHA256, lexer, mctx,
                                       &priv);
        if (result != ISC_R_SUCCESS)
                return (result);

        if (key->external)
                result = DST_R_EXTERNALKEY;

        key->key_bits = 0;
        for (i = 0; i < priv.nelements && result == ISC_R_SUCCESS; i++) {
                switch (priv.elements[i].tag) {
                case TAG_HMACSHA256_KEY:
                        isc_buffer_init(&b, priv.elements[i].data,
                                        priv.elements[i].length);
                        isc_buffer_add(&b, priv.elements[i].length);
                        tresult = hmacsha256_fromdns(key, &b);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                case TAG_HMACSHA256_BITS:
                        tresult = getkeybits(key, &priv.elements[i]);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                default:
                        result = DST_R_INVALIDPRIVATEKEY;
                        break;
                }
        }
        dst__privstruct_free(&priv, mctx);
        memset(&priv, 0, sizeof(priv));
        return (result);
}

static dst_func_t hmacsha256_functions = {
        hmacsha256_createctx,
        NULL, /*%< createctx2 */
        hmacsha256_destroyctx,
        hmacsha256_adddata,
        hmacsha256_sign,
        hmacsha256_verify,
        NULL, /* verify2 */
        NULL, /* computesecret */
        hmacsha256_compare,
        NULL, /* paramcompare */
        hmacsha256_generate,
        hmacsha256_isprivate,
        hmacsha256_destroy,
        hmacsha256_todns,
        hmacsha256_fromdns,
        hmacsha256_tofile,
        hmacsha256_parse,
        NULL, /* cleanup */
        NULL, /* fromlabel */
        NULL, /* dump */
        NULL, /* restore */
};

isc_result_t
dst__hmacsha256_init(dst_func_t **funcp) {
        REQUIRE(funcp != NULL);
        if (*funcp == NULL)
                *funcp = &hmacsha256_functions;
        return (ISC_R_SUCCESS);
}

static isc_result_t hmacsha384_fromdns(dst_key_t *key, isc_buffer_t *data);

struct dst_hmacsha384_key {
        unsigned char key[ISC_SHA384_BLOCK_LENGTH];
};

static isc_result_t
hmacsha384_createctx(dst_key_t *key, dst_context_t *dctx) {
        isc_hmacsha384_t *hmacsha384ctx;
        dst_hmacsha384_key_t *hkey = key->keydata.hmacsha384;

        hmacsha384ctx = isc_mem_get(dctx->mctx, sizeof(isc_hmacsha384_t));
        if (hmacsha384ctx == NULL)
                return (ISC_R_NOMEMORY);
        isc_hmacsha384_init(hmacsha384ctx, hkey->key, ISC_SHA384_BLOCK_LENGTH);
        dctx->ctxdata.hmacsha384ctx = hmacsha384ctx;
        return (ISC_R_SUCCESS);
}

static void
hmacsha384_destroyctx(dst_context_t *dctx) {
        isc_hmacsha384_t *hmacsha384ctx = dctx->ctxdata.hmacsha384ctx;

        if (hmacsha384ctx != NULL) {
                isc_hmacsha384_invalidate(hmacsha384ctx);
                isc_mem_put(dctx->mctx, hmacsha384ctx, sizeof(isc_hmacsha384_t));
                dctx->ctxdata.hmacsha384ctx = NULL;
        }
}

static isc_result_t
hmacsha384_adddata(dst_context_t *dctx, const isc_region_t *data) {
        isc_hmacsha384_t *hmacsha384ctx = dctx->ctxdata.hmacsha384ctx;

        isc_hmacsha384_update(hmacsha384ctx, data->base, data->length);
        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha384_sign(dst_context_t *dctx, isc_buffer_t *sig) {
        isc_hmacsha384_t *hmacsha384ctx = dctx->ctxdata.hmacsha384ctx;
        unsigned char *digest;

        if (isc_buffer_availablelength(sig) < ISC_SHA384_DIGESTLENGTH)
                return (ISC_R_NOSPACE);
        digest = isc_buffer_used(sig);
        isc_hmacsha384_sign(hmacsha384ctx, digest, ISC_SHA384_DIGESTLENGTH);
        isc_buffer_add(sig, ISC_SHA384_DIGESTLENGTH);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha384_verify(dst_context_t *dctx, const isc_region_t *sig) {
        isc_hmacsha384_t *hmacsha384ctx = dctx->ctxdata.hmacsha384ctx;

        if (sig->length > ISC_SHA384_DIGESTLENGTH || sig->length == 0)
                return (DST_R_VERIFYFAILURE);

        if (isc_hmacsha384_verify(hmacsha384ctx, sig->base, sig->length))
                return (ISC_R_SUCCESS);
        else
                return (DST_R_VERIFYFAILURE);
}

static isc_boolean_t
hmacsha384_compare(const dst_key_t *key1, const dst_key_t *key2) {
        dst_hmacsha384_key_t *hkey1, *hkey2;

        hkey1 = key1->keydata.hmacsha384;
        hkey2 = key2->keydata.hmacsha384;

        if (hkey1 == NULL && hkey2 == NULL)
                return (ISC_TRUE);
        else if (hkey1 == NULL || hkey2 == NULL)
                return (ISC_FALSE);

        if (isc_safe_memcmp(hkey1->key, hkey2->key, ISC_SHA384_BLOCK_LENGTH))
                return (ISC_TRUE);
        else
                return (ISC_FALSE);
}

static isc_result_t
hmacsha384_generate(dst_key_t *key, int pseudorandom_ok,
                    void (*callback)(int))
{
        isc_buffer_t b;
        isc_result_t ret;
        unsigned int bytes;
        unsigned char data[ISC_SHA384_BLOCK_LENGTH];

        UNUSED(callback);

        bytes = (key->key_size + 7) / 8;
        if (bytes > ISC_SHA384_BLOCK_LENGTH) {
                bytes = ISC_SHA384_BLOCK_LENGTH;
                key->key_size = ISC_SHA384_BLOCK_LENGTH * 8;
        }

        memset(data, 0, ISC_SHA384_BLOCK_LENGTH);
        ret = dst__entropy_getdata(data, bytes, ISC_TF(pseudorandom_ok != 0));

        if (ret != ISC_R_SUCCESS)
                return (ret);

        isc_buffer_init(&b, data, bytes);
        isc_buffer_add(&b, bytes);
        ret = hmacsha384_fromdns(key, &b);
        memset(data, 0, ISC_SHA384_BLOCK_LENGTH);

        return (ret);
}

static isc_boolean_t
hmacsha384_isprivate(const dst_key_t *key) {
        UNUSED(key);
        return (ISC_TRUE);
}

static void
hmacsha384_destroy(dst_key_t *key) {
        dst_hmacsha384_key_t *hkey = key->keydata.hmacsha384;

        memset(hkey, 0, sizeof(dst_hmacsha384_key_t));
        isc_mem_put(key->mctx, hkey, sizeof(dst_hmacsha384_key_t));
        key->keydata.hmacsha384 = NULL;
}

static isc_result_t
hmacsha384_todns(const dst_key_t *key, isc_buffer_t *data) {
        dst_hmacsha384_key_t *hkey;
        unsigned int bytes;

        REQUIRE(key->keydata.hmacsha384 != NULL);

        hkey = key->keydata.hmacsha384;

        bytes = (key->key_size + 7) / 8;
        if (isc_buffer_availablelength(data) < bytes)
                return (ISC_R_NOSPACE);
        isc_buffer_putmem(data, hkey->key, bytes);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha384_fromdns(dst_key_t *key, isc_buffer_t *data) {
        dst_hmacsha384_key_t *hkey;
        int keylen;
        isc_region_t r;
        isc_sha384_t sha384ctx;

        isc_buffer_remainingregion(data, &r);
        if (r.length == 0)
                return (ISC_R_SUCCESS);

        hkey = isc_mem_get(key->mctx, sizeof(dst_hmacsha384_key_t));
        if (hkey == NULL)
                return (ISC_R_NOMEMORY);

        memset(hkey->key, 0, sizeof(hkey->key));

        if (r.length > ISC_SHA384_BLOCK_LENGTH) {
                isc_sha384_init(&sha384ctx);
                isc_sha384_update(&sha384ctx, r.base, r.length);
                isc_sha384_final(hkey->key, &sha384ctx);
                keylen = ISC_SHA384_DIGESTLENGTH;
        } else {
                memmove(hkey->key, r.base, r.length);
                keylen = r.length;
        }

        key->key_size = keylen * 8;
        key->keydata.hmacsha384 = hkey;

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha384_tofile(const dst_key_t *key, const char *directory) {
        int cnt = 0;
        dst_hmacsha384_key_t *hkey;
        dst_private_t priv;
        int bytes = (key->key_size + 7) / 8;
        unsigned char buf[2];

        if (key->keydata.hmacsha384 == NULL)
                return (DST_R_NULLKEY);

        if (key->external)
                return (DST_R_EXTERNALKEY);

        hkey = key->keydata.hmacsha384;

        priv.elements[cnt].tag = TAG_HMACSHA384_KEY;
        priv.elements[cnt].length = bytes;
        priv.elements[cnt++].data = hkey->key;

        buf[0] = (key->key_bits >> 8) & 0xffU;
        buf[1] = key->key_bits & 0xffU;
        priv.elements[cnt].tag = TAG_HMACSHA384_BITS;
        priv.elements[cnt].data = buf;
        priv.elements[cnt++].length = 2;

        priv.nelements = cnt;
        return (dst__privstruct_writefile(key, &priv, directory));
}

static isc_result_t
hmacsha384_parse(dst_key_t *key, isc_lex_t *lexer, dst_key_t *pub) {
        dst_private_t priv;
        isc_result_t result, tresult;
        isc_buffer_t b;
        isc_mem_t *mctx = key->mctx;
        unsigned int i;

        UNUSED(pub);
        /* read private key file */
        result = dst__privstruct_parse(key, DST_ALG_HMACSHA384, lexer, mctx,
                                       &priv);
        if (result != ISC_R_SUCCESS)
                return (result);

        if (key->external)
                result = DST_R_EXTERNALKEY;

        key->key_bits = 0;
        for (i = 0; i < priv.nelements && result == ISC_R_SUCCESS; i++) {
                switch (priv.elements[i].tag) {
                case TAG_HMACSHA384_KEY:
                        isc_buffer_init(&b, priv.elements[i].data,
                                        priv.elements[i].length);
                        isc_buffer_add(&b, priv.elements[i].length);
                        tresult = hmacsha384_fromdns(key, &b);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                case TAG_HMACSHA384_BITS:
                        tresult = getkeybits(key, &priv.elements[i]);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                default:
                        result = DST_R_INVALIDPRIVATEKEY;
                        break;
                }
        }
        dst__privstruct_free(&priv, mctx);
        memset(&priv, 0, sizeof(priv));
        return (result);
}

static dst_func_t hmacsha384_functions = {
        hmacsha384_createctx,
        NULL, /*%< createctx2 */
        hmacsha384_destroyctx,
        hmacsha384_adddata,
        hmacsha384_sign,
        hmacsha384_verify,
        NULL, /* verify2 */
        NULL, /* computesecret */
        hmacsha384_compare,
        NULL, /* paramcompare */
        hmacsha384_generate,
        hmacsha384_isprivate,
        hmacsha384_destroy,
        hmacsha384_todns,
        hmacsha384_fromdns,
        hmacsha384_tofile,
        hmacsha384_parse,
        NULL, /* cleanup */
        NULL, /* fromlabel */
        NULL, /* dump */
        NULL, /* restore */
};

isc_result_t
dst__hmacsha384_init(dst_func_t **funcp) {
        REQUIRE(funcp != NULL);
        if (*funcp == NULL)
                *funcp = &hmacsha384_functions;
        return (ISC_R_SUCCESS);
}

static isc_result_t hmacsha512_fromdns(dst_key_t *key, isc_buffer_t *data);

struct dst_hmacsha512_key {
        unsigned char key[ISC_SHA512_BLOCK_LENGTH];
};

static isc_result_t
hmacsha512_createctx(dst_key_t *key, dst_context_t *dctx) {
        isc_hmacsha512_t *hmacsha512ctx;
        dst_hmacsha512_key_t *hkey = key->keydata.hmacsha512;

        hmacsha512ctx = isc_mem_get(dctx->mctx, sizeof(isc_hmacsha512_t));
        if (hmacsha512ctx == NULL)
                return (ISC_R_NOMEMORY);
        isc_hmacsha512_init(hmacsha512ctx, hkey->key, ISC_SHA512_BLOCK_LENGTH);
        dctx->ctxdata.hmacsha512ctx = hmacsha512ctx;
        return (ISC_R_SUCCESS);
}

static void
hmacsha512_destroyctx(dst_context_t *dctx) {
        isc_hmacsha512_t *hmacsha512ctx = dctx->ctxdata.hmacsha512ctx;

        if (hmacsha512ctx != NULL) {
                isc_hmacsha512_invalidate(hmacsha512ctx);
                isc_mem_put(dctx->mctx, hmacsha512ctx, sizeof(isc_hmacsha512_t));
                dctx->ctxdata.hmacsha512ctx = NULL;
        }
}

static isc_result_t
hmacsha512_adddata(dst_context_t *dctx, const isc_region_t *data) {
        isc_hmacsha512_t *hmacsha512ctx = dctx->ctxdata.hmacsha512ctx;

        isc_hmacsha512_update(hmacsha512ctx, data->base, data->length);
        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha512_sign(dst_context_t *dctx, isc_buffer_t *sig) {
        isc_hmacsha512_t *hmacsha512ctx = dctx->ctxdata.hmacsha512ctx;
        unsigned char *digest;

        if (isc_buffer_availablelength(sig) < ISC_SHA512_DIGESTLENGTH)
                return (ISC_R_NOSPACE);
        digest = isc_buffer_used(sig);
        isc_hmacsha512_sign(hmacsha512ctx, digest, ISC_SHA512_DIGESTLENGTH);
        isc_buffer_add(sig, ISC_SHA512_DIGESTLENGTH);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha512_verify(dst_context_t *dctx, const isc_region_t *sig) {
        isc_hmacsha512_t *hmacsha512ctx = dctx->ctxdata.hmacsha512ctx;

        if (sig->length > ISC_SHA512_DIGESTLENGTH || sig->length == 0)
                return (DST_R_VERIFYFAILURE);

        if (isc_hmacsha512_verify(hmacsha512ctx, sig->base, sig->length))
                return (ISC_R_SUCCESS);
        else
                return (DST_R_VERIFYFAILURE);
}

static isc_boolean_t
hmacsha512_compare(const dst_key_t *key1, const dst_key_t *key2) {
        dst_hmacsha512_key_t *hkey1, *hkey2;

        hkey1 = key1->keydata.hmacsha512;
        hkey2 = key2->keydata.hmacsha512;

        if (hkey1 == NULL && hkey2 == NULL)
                return (ISC_TRUE);
        else if (hkey1 == NULL || hkey2 == NULL)
                return (ISC_FALSE);

        if (isc_safe_memcmp(hkey1->key, hkey2->key, ISC_SHA512_BLOCK_LENGTH))
                return (ISC_TRUE);
        else
                return (ISC_FALSE);
}

static isc_result_t
hmacsha512_generate(dst_key_t *key, int pseudorandom_ok,
                    void (*callback)(int))
{
        isc_buffer_t b;
        isc_result_t ret;
        unsigned int bytes;
        unsigned char data[ISC_SHA512_BLOCK_LENGTH];

        UNUSED(callback);

        bytes = (key->key_size + 7) / 8;
        if (bytes > ISC_SHA512_BLOCK_LENGTH) {
                bytes = ISC_SHA512_BLOCK_LENGTH;
                key->key_size = ISC_SHA512_BLOCK_LENGTH * 8;
        }

        memset(data, 0, ISC_SHA512_BLOCK_LENGTH);
        ret = dst__entropy_getdata(data, bytes, ISC_TF(pseudorandom_ok != 0));

        if (ret != ISC_R_SUCCESS)
                return (ret);

        isc_buffer_init(&b, data, bytes);
        isc_buffer_add(&b, bytes);
        ret = hmacsha512_fromdns(key, &b);
        memset(data, 0, ISC_SHA512_BLOCK_LENGTH);

        return (ret);
}

static isc_boolean_t
hmacsha512_isprivate(const dst_key_t *key) {
        UNUSED(key);
        return (ISC_TRUE);
}

static void
hmacsha512_destroy(dst_key_t *key) {
        dst_hmacsha512_key_t *hkey = key->keydata.hmacsha512;

        memset(hkey, 0, sizeof(dst_hmacsha512_key_t));
        isc_mem_put(key->mctx, hkey, sizeof(dst_hmacsha512_key_t));
        key->keydata.hmacsha512 = NULL;
}

static isc_result_t
hmacsha512_todns(const dst_key_t *key, isc_buffer_t *data) {
        dst_hmacsha512_key_t *hkey;
        unsigned int bytes;

        REQUIRE(key->keydata.hmacsha512 != NULL);

        hkey = key->keydata.hmacsha512;

        bytes = (key->key_size + 7) / 8;
        if (isc_buffer_availablelength(data) < bytes)
                return (ISC_R_NOSPACE);
        isc_buffer_putmem(data, hkey->key, bytes);

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha512_fromdns(dst_key_t *key, isc_buffer_t *data) {
        dst_hmacsha512_key_t *hkey;
        int keylen;
        isc_region_t r;
        isc_sha512_t sha512ctx;

        isc_buffer_remainingregion(data, &r);
        if (r.length == 0)
                return (ISC_R_SUCCESS);

        hkey = isc_mem_get(key->mctx, sizeof(dst_hmacsha512_key_t));
        if (hkey == NULL)
                return (ISC_R_NOMEMORY);

        memset(hkey->key, 0, sizeof(hkey->key));

        if (r.length > ISC_SHA512_BLOCK_LENGTH) {
                isc_sha512_init(&sha512ctx);
                isc_sha512_update(&sha512ctx, r.base, r.length);
                isc_sha512_final(hkey->key, &sha512ctx);
                keylen = ISC_SHA512_DIGESTLENGTH;
        } else {
                memmove(hkey->key, r.base, r.length);
                keylen = r.length;
        }

        key->key_size = keylen * 8;
        key->keydata.hmacsha512 = hkey;

        return (ISC_R_SUCCESS);
}

static isc_result_t
hmacsha512_tofile(const dst_key_t *key, const char *directory) {
        int cnt = 0;
        dst_hmacsha512_key_t *hkey;
        dst_private_t priv;
        int bytes = (key->key_size + 7) / 8;
        unsigned char buf[2];

        if (key->keydata.hmacsha512 == NULL)
                return (DST_R_NULLKEY);

        if (key->external)
                return (DST_R_EXTERNALKEY);

        hkey = key->keydata.hmacsha512;

        priv.elements[cnt].tag = TAG_HMACSHA512_KEY;
        priv.elements[cnt].length = bytes;
        priv.elements[cnt++].data = hkey->key;

        buf[0] = (key->key_bits >> 8) & 0xffU;
        buf[1] = key->key_bits & 0xffU;
        priv.elements[cnt].tag = TAG_HMACSHA512_BITS;
        priv.elements[cnt].data = buf;
        priv.elements[cnt++].length = 2;

        priv.nelements = cnt;
        return (dst__privstruct_writefile(key, &priv, directory));
}

static isc_result_t
hmacsha512_parse(dst_key_t *key, isc_lex_t *lexer, dst_key_t *pub) {
        dst_private_t priv;
        isc_result_t result, tresult;
        isc_buffer_t b;
        isc_mem_t *mctx = key->mctx;
        unsigned int i;

        UNUSED(pub);
        /* read private key file */
        result = dst__privstruct_parse(key, DST_ALG_HMACSHA512, lexer, mctx,
                                       &priv);
        if (result != ISC_R_SUCCESS)
                return (result);

        if (key->external)
                result = DST_R_EXTERNALKEY;

        key->key_bits = 0;
        for (i = 0; i < priv.nelements && result == ISC_R_SUCCESS; i++) {
                switch (priv.elements[i].tag) {
                case TAG_HMACSHA512_KEY:
                        isc_buffer_init(&b, priv.elements[i].data,
                                        priv.elements[i].length);
                        isc_buffer_add(&b, priv.elements[i].length);
                        tresult = hmacsha512_fromdns(key, &b);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                case TAG_HMACSHA512_BITS:
                        tresult = getkeybits(key, &priv.elements[i]);
                        if (tresult != ISC_R_SUCCESS)
                                result = tresult;
                        break;
                default:
                        result = DST_R_INVALIDPRIVATEKEY;
                        break;
                }
        }
        dst__privstruct_free(&priv, mctx);
        memset(&priv, 0, sizeof(priv));
        return (result);
}

static dst_func_t hmacsha512_functions = {
        hmacsha512_createctx,
        NULL, /*%< createctx2 */
        hmacsha512_destroyctx,
        hmacsha512_adddata,
        hmacsha512_sign,
        hmacsha512_verify,
        NULL, /* verify2 */
        NULL, /* computesecret */
        hmacsha512_compare,
        NULL, /* paramcompare */
        hmacsha512_generate,
        hmacsha512_isprivate,
        hmacsha512_destroy,
        hmacsha512_todns,
        hmacsha512_fromdns,
        hmacsha512_tofile,
        hmacsha512_parse,
        NULL, /* cleanup */
        NULL, /* fromlabel */
        NULL, /* dump */
        NULL, /* restore */
};

isc_result_t
dst__hmacsha512_init(dst_func_t **funcp) {
        REQUIRE(funcp != NULL);
        if (*funcp == NULL)
                *funcp = &hmacsha512_functions;
        return (ISC_R_SUCCESS);
}

/*! \file */

---