openssldsa_link.c revision 81aea2f2d3eac0515eb29449977ad50752f42a39
/*
* Portions Copyright (C) 1999-2001 Internet Software Consortium.
* Portions Copyright (C) 1995-2000 by Network Associates, Inc.
*
* 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 AND
* NETWORK ASSOCIATES DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE CONSORTIUM OR NETWORK
* ASSOCIATES 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: openssldsa_link.c,v 1.13 2002/12/13 02:51:41 marka Exp $ */
#ifdef OPENSSL
#include <config.h>
#include <string.h>
#include <isc/entropy.h>
#include <isc/mem.h>
#include <isc/sha1.h>
#include <isc/util.h>
#include <dst/result.h>
#include "dst_internal.h"
#include "dst_openssl.h"
#include "dst_parse.h"
#include <openssl/dsa.h>
static isc_result_t openssldsa_todns(const dst_key_t *key, isc_buffer_t *data);
static isc_result_t
openssldsa_createctx(dst_key_t *key, dst_context_t *dctx) {
isc_sha1_t *sha1ctx;
UNUSED(key);
sha1ctx = isc_mem_get(dctx->mctx, sizeof(isc_sha1_t));
isc_sha1_init(sha1ctx);
dctx->opaque = sha1ctx;
return (ISC_R_SUCCESS);
}
static void
openssldsa_destroyctx(dst_context_t *dctx) {
isc_sha1_t *sha1ctx = dctx->opaque;
if (sha1ctx != NULL) {
isc_sha1_invalidate(sha1ctx);
isc_mem_put(dctx->mctx, sha1ctx, sizeof(isc_sha1_t));
dctx->opaque = NULL;
}
}
static isc_result_t
openssldsa_adddata(dst_context_t *dctx, const isc_region_t *data) {
isc_sha1_t *sha1ctx = dctx->opaque;
isc_sha1_update(sha1ctx, data->base, data->length);
return (ISC_R_SUCCESS);
}
static int
BN_bn2bin_fixed(BIGNUM *bn, unsigned char *buf, int size) {
int bytes = size - BN_num_bytes(bn);
while (bytes-- > 0)
*buf++ = 0;
BN_bn2bin(bn, buf);
return (size);
}
static isc_result_t
openssldsa_sign(dst_context_t *dctx, isc_buffer_t *sig) {
isc_sha1_t *sha1ctx = dctx->opaque;
dst_key_t *key = dctx->key;
DSA *dsa = key->opaque;
DSA_SIG *dsasig;
isc_region_t r;
unsigned char digest[ISC_SHA1_DIGESTLENGTH];
isc_buffer_availableregion(sig, &r);
if (r.length < ISC_SHA1_DIGESTLENGTH * 2 + 1)
return (ISC_R_NOSPACE);
isc_sha1_final(sha1ctx, digest);
dsasig = DSA_do_sign(digest, ISC_SHA1_DIGESTLENGTH, dsa);
if (dsasig == NULL)
return (dst__openssl_toresult(DST_R_SIGNFAILURE));
*r.base++ = (key->key_size - 512)/64;
BN_bn2bin_fixed(dsasig->r, r.base, ISC_SHA1_DIGESTLENGTH);
r.base += ISC_SHA1_DIGESTLENGTH;
BN_bn2bin_fixed(dsasig->s, r.base, ISC_SHA1_DIGESTLENGTH);
r.base += ISC_SHA1_DIGESTLENGTH;
DSA_SIG_free(dsasig);
isc_buffer_add(sig, ISC_SHA1_DIGESTLENGTH * 2 + 1);
return (ISC_R_SUCCESS);
}
static isc_result_t
openssldsa_verify(dst_context_t *dctx, const isc_region_t *sig) {
isc_sha1_t *sha1ctx = dctx->opaque;
dst_key_t *key = dctx->key;
DSA *dsa = key->opaque;
DSA_SIG *dsasig;
int status = 0;
unsigned char digest[ISC_SHA1_DIGESTLENGTH];
unsigned char *cp = sig->base;
isc_sha1_final(sha1ctx, digest);
if (sig->length < 2 * ISC_SHA1_DIGESTLENGTH + 1)
return (DST_R_VERIFYFAILURE);
cp++; /* Skip T */
dsasig = DSA_SIG_new();
dsasig->r = BN_bin2bn(cp, ISC_SHA1_DIGESTLENGTH, NULL);
cp += ISC_SHA1_DIGESTLENGTH;
dsasig->s = BN_bin2bn(cp, ISC_SHA1_DIGESTLENGTH, NULL);
cp += ISC_SHA1_DIGESTLENGTH;
status = DSA_do_verify(digest, ISC_SHA1_DIGESTLENGTH, dsasig, dsa);
DSA_SIG_free(dsasig);
if (status == 0)
return (dst__openssl_toresult(DST_R_VERIFYFAILURE));
return (ISC_R_SUCCESS);
}
static isc_boolean_t
openssldsa_compare(const dst_key_t *key1, const dst_key_t *key2) {
int status;
DSA *dsa1, *dsa2;
dsa1 = (DSA *) key1->opaque;
dsa2 = (DSA *) key2->opaque;
if (dsa1 == NULL && dsa2 == NULL)
return (ISC_TRUE);
else if (dsa1 == NULL || dsa2 == NULL)
return (ISC_FALSE);
status = BN_cmp(dsa1->p, dsa2->p) ||
BN_cmp(dsa1->q, dsa2->q) ||
BN_cmp(dsa1->g, dsa2->g) ||
BN_cmp(dsa1->pub_key, dsa2->pub_key);
if (status != 0)
return (ISC_FALSE);
if (dsa1->priv_key != NULL || dsa2->priv_key != NULL) {
if (dsa1->priv_key == NULL || dsa2->priv_key == NULL)
return (ISC_FALSE);
if (BN_cmp(dsa1->priv_key, dsa2->priv_key))
return (ISC_FALSE);
}
return (ISC_TRUE);
}
static isc_result_t
openssldsa_generate(dst_key_t *key, int unused) {
DSA *dsa;
unsigned char rand_array[ISC_SHA1_DIGESTLENGTH];
isc_result_t result;
UNUSED(unused);
result = dst__entropy_getdata(rand_array, sizeof(rand_array),
ISC_FALSE);
if (result != ISC_R_SUCCESS)
return (result);
dsa = DSA_generate_parameters(key->key_size, rand_array,
ISC_SHA1_DIGESTLENGTH, NULL, NULL,
NULL, NULL);
if (dsa == NULL)
return (dst__openssl_toresult(DST_R_OPENSSLFAILURE));
if (DSA_generate_key(dsa) == 0) {
DSA_free(dsa);
return (dst__openssl_toresult(DST_R_OPENSSLFAILURE));
}
dsa->flags &= ~DSA_FLAG_CACHE_MONT_P;
key->opaque = dsa;
return (ISC_R_SUCCESS);
}
static isc_boolean_t
openssldsa_isprivate(const dst_key_t *key) {
DSA *dsa = (DSA *) key->opaque;
return (ISC_TF(dsa != NULL && dsa->priv_key != NULL));
}
static void
openssldsa_destroy(dst_key_t *key) {
DSA *dsa = key->opaque;
DSA_free(dsa);
key->opaque = NULL;
}
static isc_result_t
openssldsa_todns(const dst_key_t *key, isc_buffer_t *data) {
DSA *dsa;
isc_region_t r;
int dnslen;
unsigned int t, p_bytes;
REQUIRE(key->opaque != NULL);
dsa = (DSA *) key->opaque;
isc_buffer_availableregion(data, &r);
t = (BN_num_bytes(dsa->p) - 64) / 8;
if (t > 8)
return (DST_R_INVALIDPUBLICKEY);
p_bytes = 64 + 8 * t;
dnslen = 1 + (key->key_size * 3)/8 + ISC_SHA1_DIGESTLENGTH;
if (r.length < (unsigned int) dnslen)
return (ISC_R_NOSPACE);
*r.base++ = t;
BN_bn2bin_fixed(dsa->q, r.base, ISC_SHA1_DIGESTLENGTH);
r.base += ISC_SHA1_DIGESTLENGTH;
BN_bn2bin_fixed(dsa->p, r.base, key->key_size/8);
r.base += p_bytes;
BN_bn2bin_fixed(dsa->g, r.base, key->key_size/8);
r.base += p_bytes;
BN_bn2bin_fixed(dsa->pub_key, r.base, key->key_size/8);
r.base += p_bytes;
isc_buffer_add(data, dnslen);
return (ISC_R_SUCCESS);
}
static isc_result_t
openssldsa_fromdns(dst_key_t *key, isc_buffer_t *data) {
DSA *dsa;
isc_region_t r;
unsigned int t, p_bytes;
isc_mem_t *mctx = key->mctx;
UNUSED(mctx);
isc_buffer_remainingregion(data, &r);
if (r.length == 0)
return (ISC_R_SUCCESS);
dsa = DSA_new();
if (dsa == NULL)
return (ISC_R_NOMEMORY);
dsa->flags &= ~DSA_FLAG_CACHE_MONT_P;
t = (unsigned int) *r.base++;
if (t > 8) {
DSA_free(dsa);
return (DST_R_INVALIDPUBLICKEY);
}
p_bytes = 64 + 8 * t;
if (r.length < 1 + ISC_SHA1_DIGESTLENGTH + 3 * p_bytes) {
DSA_free(dsa);
return (DST_R_INVALIDPUBLICKEY);
}
dsa->q = BN_bin2bn(r.base, ISC_SHA1_DIGESTLENGTH, NULL);
r.base += ISC_SHA1_DIGESTLENGTH;
dsa->p = BN_bin2bn(r.base, p_bytes, NULL);
r.base += p_bytes;
dsa->g = BN_bin2bn(r.base, p_bytes, NULL);
r.base += p_bytes;
dsa->pub_key = BN_bin2bn(r.base, p_bytes, NULL);
r.base += p_bytes;
key->key_size = p_bytes * 8;
isc_buffer_forward(data, 1 + ISC_SHA1_DIGESTLENGTH + 3 * p_bytes);
key->opaque = (void *) dsa;
return (ISC_R_SUCCESS);
}
static isc_result_t
openssldsa_tofile(const dst_key_t *key, const char *directory) {
int cnt = 0;
DSA *dsa;
dst_private_t priv;
unsigned char bufs[5][128];
if (key->opaque == NULL)
return (DST_R_NULLKEY);
dsa = (DSA *) key->opaque;
priv.elements[cnt].tag = TAG_DSA_PRIME;
priv.elements[cnt].length = BN_num_bytes(dsa->p);
BN_bn2bin(dsa->p, bufs[cnt]);
priv.elements[cnt].data = bufs[cnt];
cnt++;
priv.elements[cnt].tag = TAG_DSA_SUBPRIME;
priv.elements[cnt].length = BN_num_bytes(dsa->q);
BN_bn2bin(dsa->q, bufs[cnt]);
priv.elements[cnt].data = bufs[cnt];
cnt++;
priv.elements[cnt].tag = TAG_DSA_BASE;
priv.elements[cnt].length = BN_num_bytes(dsa->g);
BN_bn2bin(dsa->g, bufs[cnt]);
priv.elements[cnt].data = bufs[cnt];
cnt++;
priv.elements[cnt].tag = TAG_DSA_PRIVATE;
priv.elements[cnt].length = BN_num_bytes(dsa->priv_key);
BN_bn2bin(dsa->priv_key, bufs[cnt]);
priv.elements[cnt].data = bufs[cnt];
cnt++;
priv.elements[cnt].tag = TAG_DSA_PUBLIC;
priv.elements[cnt].length = BN_num_bytes(dsa->pub_key);
BN_bn2bin(dsa->pub_key, bufs[cnt]);
priv.elements[cnt].data = bufs[cnt];
cnt++;
priv.nelements = cnt;
return (dst__privstruct_writefile(key, &priv, directory));
}
static isc_result_t
openssldsa_parse(dst_key_t *key, isc_lex_t *lexer) {
dst_private_t priv;
isc_result_t ret;
int i;
DSA *dsa = NULL;
isc_mem_t *mctx = key->mctx;
#define DST_RET(a) {ret = a; goto err;}
/* read private key file */
ret = dst__privstruct_parse(key, DST_ALG_DSA, lexer, mctx, &priv);
if (ret != ISC_R_SUCCESS)
return (ret);
dsa = DSA_new();
if (dsa == NULL)
DST_RET(ISC_R_NOMEMORY);
dsa->flags &= ~DSA_FLAG_CACHE_MONT_P;
key->opaque = dsa;
for (i=0; i < priv.nelements; i++) {
BIGNUM *bn;
bn = BN_bin2bn(priv.elements[i].data,
priv.elements[i].length, NULL);
if (bn == NULL)
DST_RET(ISC_R_NOMEMORY);
switch (priv.elements[i].tag) {
case TAG_DSA_PRIME:
dsa->p = bn;
break;
case TAG_DSA_SUBPRIME:
dsa->q = bn;
break;
case TAG_DSA_BASE:
dsa->g = bn;
break;
case TAG_DSA_PRIVATE:
dsa->priv_key = bn;
break;
case TAG_DSA_PUBLIC:
dsa->pub_key = bn;
break;
}
}
dst__privstruct_free(&priv, mctx);
key->key_size = BN_num_bits(dsa->p);
return (ISC_R_SUCCESS);
err:
openssldsa_destroy(key);
dst__privstruct_free(&priv, mctx);
memset(&priv, 0, sizeof(priv));
return (ret);
}
static dst_func_t openssldsa_functions = {
openssldsa_createctx,
openssldsa_destroyctx,
openssldsa_adddata,
openssldsa_sign,
openssldsa_verify,
NULL, /* computesecret */
openssldsa_compare,
NULL, /* paramcompare */
openssldsa_generate,
openssldsa_isprivate,
openssldsa_destroy,
openssldsa_todns,
openssldsa_fromdns,
openssldsa_tofile,
openssldsa_parse,
NULL, /* cleanup */
};
isc_result_t
dst__openssldsa_init(dst_func_t **funcp) {
REQUIRE(funcp != NULL);
if (*funcp == NULL)
*funcp = &openssldsa_functions;
return (ISC_R_SUCCESS);
}
#else /* OPENSSL */
#include <isc/util.h>
EMPTY_TRANSLATION_UNIT
#endif /* OPENSSL */