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- /* crypto/engine/eng_rsax.c */
- /* Copyright (c) 2010-2010 Intel Corp.
- * Author: [email protected]
- * Jim Guilford
- * [email protected]
- * [email protected]
- * [email protected]
- *
- * More information about algorithm used can be found at:
- * http://www.cse.buffalo.edu/srds2009/escs2009_submission_Gopal.pdf
- */
- /* ====================================================================
- * Copyright (c) 1999-2001 The OpenSSL Project. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * 3. All advertising materials mentioning features or use of this
- * software must display the following acknowledgment:
- * "This product includes software developed by the OpenSSL Project
- * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
- *
- * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
- * endorse or promote products derived from this software without
- * prior written permission. For written permission, please contact
- * [email protected].
- *
- * 5. Products derived from this software may not be called "OpenSSL"
- * nor may "OpenSSL" appear in their names without prior written
- * permission of the OpenSSL Project.
- *
- * 6. Redistributions of any form whatsoever must retain the following
- * acknowledgment:
- * "This product includes software developed by the OpenSSL Project
- * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
- *
- * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
- * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
- * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
- * OF THE POSSIBILITY OF SUCH DAMAGE.
- * ====================================================================
- *
- * This product includes cryptographic software written by Eric Young
- * ([email protected]). This product includes software written by Tim
- * Hudson ([email protected]).
- */
- #include <openssl/opensslconf.h>
- #include <stdio.h>
- #include <string.h>
- #include <openssl/crypto.h>
- #include <openssl/buffer.h>
- #include <openssl/engine.h>
- #ifndef OPENSSL_NO_RSA
- # include <openssl/rsa.h>
- #endif
- #include <openssl/bn.h>
- #include <openssl/err.h>
- /* RSAX is available **ONLY* on x86_64 CPUs */
- #undef COMPILE_RSAX
- #if (defined(__x86_64) || defined(__x86_64__) || \
- defined(_M_AMD64) || defined (_M_X64)) && !defined(OPENSSL_NO_ASM)
- # define COMPILE_RSAX
- static ENGINE *ENGINE_rsax(void);
- #endif
- void ENGINE_load_rsax(void)
- {
- /* On non-x86 CPUs it just returns. */
- #ifdef COMPILE_RSAX
- ENGINE *toadd = ENGINE_rsax();
- if (!toadd)
- return;
- ENGINE_add(toadd);
- ENGINE_free(toadd);
- ERR_clear_error();
- #endif
- }
- #ifdef COMPILE_RSAX
- # define E_RSAX_LIB_NAME "rsax engine"
- static int e_rsax_destroy(ENGINE *e);
- static int e_rsax_init(ENGINE *e);
- static int e_rsax_finish(ENGINE *e);
- static int e_rsax_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f) (void));
- # ifndef OPENSSL_NO_RSA
- /* RSA stuff */
- static int e_rsax_rsa_mod_exp(BIGNUM *r, const BIGNUM *I, RSA *rsa,
- BN_CTX *ctx);
- static int e_rsax_rsa_finish(RSA *r);
- # endif
- static const ENGINE_CMD_DEFN e_rsax_cmd_defns[] = {
- {0, NULL, NULL, 0}
- };
- # ifndef OPENSSL_NO_RSA
- /* Our internal RSA_METHOD that we provide pointers to */
- static RSA_METHOD e_rsax_rsa = {
- "Intel RSA-X method",
- NULL,
- NULL,
- NULL,
- NULL,
- e_rsax_rsa_mod_exp,
- NULL,
- NULL,
- e_rsax_rsa_finish,
- RSA_FLAG_CACHE_PUBLIC | RSA_FLAG_CACHE_PRIVATE,
- NULL,
- NULL,
- NULL
- };
- # endif
- /* Constants used when creating the ENGINE */
- static const char *engine_e_rsax_id = "rsax";
- static const char *engine_e_rsax_name = "RSAX engine support";
- /* This internal function is used by ENGINE_rsax() */
- static int bind_helper(ENGINE *e)
- {
- # ifndef OPENSSL_NO_RSA
- const RSA_METHOD *meth1;
- # endif
- if (!ENGINE_set_id(e, engine_e_rsax_id) ||
- !ENGINE_set_name(e, engine_e_rsax_name) ||
- # ifndef OPENSSL_NO_RSA
- !ENGINE_set_RSA(e, &e_rsax_rsa) ||
- # endif
- !ENGINE_set_destroy_function(e, e_rsax_destroy) ||
- !ENGINE_set_init_function(e, e_rsax_init) ||
- !ENGINE_set_finish_function(e, e_rsax_finish) ||
- !ENGINE_set_ctrl_function(e, e_rsax_ctrl) ||
- !ENGINE_set_cmd_defns(e, e_rsax_cmd_defns))
- return 0;
- # ifndef OPENSSL_NO_RSA
- meth1 = RSA_PKCS1_SSLeay();
- e_rsax_rsa.rsa_pub_enc = meth1->rsa_pub_enc;
- e_rsax_rsa.rsa_pub_dec = meth1->rsa_pub_dec;
- e_rsax_rsa.rsa_priv_enc = meth1->rsa_priv_enc;
- e_rsax_rsa.rsa_priv_dec = meth1->rsa_priv_dec;
- e_rsax_rsa.bn_mod_exp = meth1->bn_mod_exp;
- # endif
- return 1;
- }
- static ENGINE *ENGINE_rsax(void)
- {
- ENGINE *ret = ENGINE_new();
- if (!ret)
- return NULL;
- if (!bind_helper(ret)) {
- ENGINE_free(ret);
- return NULL;
- }
- return ret;
- }
- # ifndef OPENSSL_NO_RSA
- /* Used to attach our own key-data to an RSA structure */
- static int rsax_ex_data_idx = -1;
- # endif
- static int e_rsax_destroy(ENGINE *e)
- {
- return 1;
- }
- /* (de)initialisation functions. */
- static int e_rsax_init(ENGINE *e)
- {
- # ifndef OPENSSL_NO_RSA
- if (rsax_ex_data_idx == -1)
- rsax_ex_data_idx = RSA_get_ex_new_index(0, NULL, NULL, NULL, NULL);
- # endif
- if (rsax_ex_data_idx == -1)
- return 0;
- return 1;
- }
- static int e_rsax_finish(ENGINE *e)
- {
- return 1;
- }
- static int e_rsax_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f) (void))
- {
- int to_return = 1;
- switch (cmd) {
- /* The command isn't understood by this engine */
- default:
- to_return = 0;
- break;
- }
- return to_return;
- }
- # ifndef OPENSSL_NO_RSA
- # ifdef _WIN32
- typedef unsigned __int64 UINT64;
- # else
- typedef unsigned long long UINT64;
- # endif
- typedef unsigned short UINT16;
- /*
- * Table t is interleaved in the following manner: The order in memory is
- * t[0][0], t[0][1], ..., t[0][7], t[1][0], ... A particular 512-bit value is
- * stored in t[][index] rather than the more normal t[index][]; i.e. the
- * qwords of a particular entry in t are not adjacent in memory
- */
- /* Init BIGNUM b from the interleaved UINT64 array */
- static int interleaved_array_to_bn_512(BIGNUM *b, UINT64 *array);
- /*
- * Extract array elements from BIGNUM b To set the whole array from b, call
- * with n=8
- */
- static int bn_extract_to_array_512(const BIGNUM *b, unsigned int n,
- UINT64 *array);
- struct mod_ctx_512 {
- UINT64 t[8][8];
- UINT64 m[8];
- UINT64 m1[8]; /* 2^278 % m */
- UINT64 m2[8]; /* 2^640 % m */
- UINT64 k1[2]; /* (- 1/m) % 2^128 */
- };
- static int mod_exp_pre_compute_data_512(UINT64 *m, struct mod_ctx_512 *data);
- void mod_exp_512(UINT64 *result, /* 512 bits, 8 qwords */
- UINT64 *g, /* 512 bits, 8 qwords */
- UINT64 *exp, /* 512 bits, 8 qwords */
- struct mod_ctx_512 *data);
- typedef struct st_e_rsax_mod_ctx {
- UINT64 type;
- union {
- struct mod_ctx_512 b512;
- } ctx;
- } E_RSAX_MOD_CTX;
- static E_RSAX_MOD_CTX *e_rsax_get_ctx(RSA *rsa, int idx, BIGNUM *m)
- {
- E_RSAX_MOD_CTX *hptr;
- if (idx < 0 || idx > 2)
- return NULL;
- hptr = RSA_get_ex_data(rsa, rsax_ex_data_idx);
- if (!hptr) {
- hptr = OPENSSL_malloc(3 * sizeof(E_RSAX_MOD_CTX));
- if (!hptr)
- return NULL;
- hptr[2].type = hptr[1].type = hptr[0].type = 0;
- RSA_set_ex_data(rsa, rsax_ex_data_idx, hptr);
- }
- if (hptr[idx].type == (UINT64)BN_num_bits(m))
- return hptr + idx;
- if (BN_num_bits(m) == 512) {
- UINT64 _m[8];
- bn_extract_to_array_512(m, 8, _m);
- memset(&hptr[idx].ctx.b512, 0, sizeof(struct mod_ctx_512));
- mod_exp_pre_compute_data_512(_m, &hptr[idx].ctx.b512);
- }
- hptr[idx].type = BN_num_bits(m);
- return hptr + idx;
- }
- static int e_rsax_rsa_finish(RSA *rsa)
- {
- E_RSAX_MOD_CTX *hptr = RSA_get_ex_data(rsa, rsax_ex_data_idx);
- if (hptr) {
- OPENSSL_free(hptr);
- RSA_set_ex_data(rsa, rsax_ex_data_idx, NULL);
- }
- if (rsa->_method_mod_n)
- BN_MONT_CTX_free(rsa->_method_mod_n);
- if (rsa->_method_mod_p)
- BN_MONT_CTX_free(rsa->_method_mod_p);
- if (rsa->_method_mod_q)
- BN_MONT_CTX_free(rsa->_method_mod_q);
- return 1;
- }
- static int e_rsax_bn_mod_exp(BIGNUM *r, const BIGNUM *g, const BIGNUM *e,
- const BIGNUM *m, BN_CTX *ctx,
- BN_MONT_CTX *in_mont,
- E_RSAX_MOD_CTX *rsax_mod_ctx)
- {
- if (rsax_mod_ctx && BN_get_flags(e, BN_FLG_CONSTTIME) != 0) {
- if (BN_num_bits(m) == 512) {
- UINT64 _r[8];
- UINT64 _g[8];
- UINT64 _e[8];
- /* Init the arrays from the BIGNUMs */
- bn_extract_to_array_512(g, 8, _g);
- bn_extract_to_array_512(e, 8, _e);
- mod_exp_512(_r, _g, _e, &rsax_mod_ctx->ctx.b512);
- /* Return the result in the BIGNUM */
- interleaved_array_to_bn_512(r, _r);
- return 1;
- }
- }
- return BN_mod_exp_mont(r, g, e, m, ctx, in_mont);
- }
- /*
- * Declares for the Intel CIAP 512-bit / CRT / 1024 bit RSA modular
- * exponentiation routine precalculations and a structure to hold the
- * necessary values. These files are meant to live in crypto/rsa/ in the
- * target openssl.
- */
- /*
- * Local method: extracts a piece from a BIGNUM, to fit it into
- * an array. Call with n=8 to extract an entire 512-bit BIGNUM
- */
- static int bn_extract_to_array_512(const BIGNUM *b, unsigned int n,
- UINT64 *array)
- {
- int i;
- UINT64 tmp;
- unsigned char bn_buff[64];
- memset(bn_buff, 0, 64);
- if (BN_num_bytes(b) > 64) {
- printf("Can't support this byte size\n");
- return 0;
- }
- if (BN_num_bytes(b) != 0) {
- if (!BN_bn2bin(b, bn_buff + (64 - BN_num_bytes(b)))) {
- printf("Error's in bn2bin\n");
- /* We have to error, here */
- return 0;
- }
- }
- while (n-- > 0) {
- array[n] = 0;
- for (i = 7; i >= 0; i--) {
- tmp = bn_buff[63 - (n * 8 + i)];
- array[n] |= tmp << (8 * i);
- }
- }
- return 1;
- }
- /* Init a 512-bit BIGNUM from the UINT64*_ (8 * 64) interleaved array */
- static int interleaved_array_to_bn_512(BIGNUM *b, UINT64 *array)
- {
- unsigned char tmp[64];
- int n = 8;
- int i;
- while (n-- > 0) {
- for (i = 7; i >= 0; i--) {
- tmp[63 - (n * 8 + i)] = (unsigned char)(array[n] >> (8 * i));
- }}
- BN_bin2bn(tmp, 64, b);
- return 0;
- }
- /* The main 512bit precompute call */
- static int mod_exp_pre_compute_data_512(UINT64 *m, struct mod_ctx_512 *data)
- {
- BIGNUM two_768, two_640, two_128, two_512, tmp, _m, tmp2;
- /* We need a BN_CTX for the modulo functions */
- BN_CTX *ctx;
- /* Some tmps */
- UINT64 _t[8];
- int i, j, ret = 0;
- /* Init _m with m */
- BN_init(&_m);
- interleaved_array_to_bn_512(&_m, m);
- memset(_t, 0, 64);
- /* Inits */
- BN_init(&two_768);
- BN_init(&two_640);
- BN_init(&two_128);
- BN_init(&two_512);
- BN_init(&tmp);
- BN_init(&tmp2);
- /* Create our context */
- if ((ctx = BN_CTX_new()) == NULL) {
- goto err;
- }
- BN_CTX_start(ctx);
- /*
- * For production, if you care, these only need to be set once,
- * and may be made constants.
- */
- BN_lshift(&two_768, BN_value_one(), 768);
- BN_lshift(&two_640, BN_value_one(), 640);
- BN_lshift(&two_128, BN_value_one(), 128);
- BN_lshift(&two_512, BN_value_one(), 512);
- if (0 == (m[7] & 0x8000000000000000)) {
- goto err;
- }
- if (0 == (m[0] & 0x1)) { /* Odd modulus required for Mont */
- goto err;
- }
- /* Precompute m1 */
- BN_mod(&tmp, &two_768, &_m, ctx);
- if (!bn_extract_to_array_512(&tmp, 8, &data->m1[0])) {
- goto err;
- }
- /* Precompute m2 */
- BN_mod(&tmp, &two_640, &_m, ctx);
- if (!bn_extract_to_array_512(&tmp, 8, &data->m2[0])) {
- goto err;
- }
- /*
- * Precompute k1, a 128b number = ((-1)* m-1 ) mod 2128; k1 should
- * be non-negative.
- */
- BN_mod_inverse(&tmp, &_m, &two_128, ctx);
- if (!BN_is_zero(&tmp)) {
- BN_sub(&tmp, &two_128, &tmp);
- }
- if (!bn_extract_to_array_512(&tmp, 2, &data->k1[0])) {
- goto err;
- }
- /* Precompute t */
- for (i = 0; i < 8; i++) {
- BN_zero(&tmp);
- if (i & 1) {
- BN_add(&tmp, &two_512, &tmp);
- }
- if (i & 2) {
- BN_add(&tmp, &two_512, &tmp);
- }
- if (i & 4) {
- BN_add(&tmp, &two_640, &tmp);
- }
- BN_nnmod(&tmp2, &tmp, &_m, ctx);
- if (!bn_extract_to_array_512(&tmp2, 8, _t)) {
- goto err;
- }
- for (j = 0; j < 8; j++)
- data->t[j][i] = _t[j];
- }
- /* Precompute m */
- for (i = 0; i < 8; i++) {
- data->m[i] = m[i];
- }
- ret = 1;
- err:
- /* Cleanup */
- if (ctx != NULL) {
- BN_CTX_end(ctx);
- BN_CTX_free(ctx);
- }
- BN_free(&two_768);
- BN_free(&two_640);
- BN_free(&two_128);
- BN_free(&two_512);
- BN_free(&tmp);
- BN_free(&tmp2);
- BN_free(&_m);
- return ret;
- }
- static int e_rsax_rsa_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa,
- BN_CTX *ctx)
- {
- BIGNUM *r1, *m1, *vrfy;
- BIGNUM local_dmp1, local_dmq1, local_c, local_r1;
- BIGNUM *dmp1, *dmq1, *c, *pr1;
- int ret = 0;
- BN_CTX_start(ctx);
- r1 = BN_CTX_get(ctx);
- m1 = BN_CTX_get(ctx);
- vrfy = BN_CTX_get(ctx);
- {
- BIGNUM local_p, local_q;
- BIGNUM *p = NULL, *q = NULL;
- int error = 0;
- /*
- * Make sure BN_mod_inverse in Montgomery intialization uses the
- * BN_FLG_CONSTTIME flag (unless RSA_FLAG_NO_CONSTTIME is set)
- */
- if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
- BN_init(&local_p);
- p = &local_p;
- BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);
- BN_init(&local_q);
- q = &local_q;
- BN_with_flags(q, rsa->q, BN_FLG_CONSTTIME);
- } else {
- p = rsa->p;
- q = rsa->q;
- }
- if (rsa->flags & RSA_FLAG_CACHE_PRIVATE) {
- if (!BN_MONT_CTX_set_locked
- (&rsa->_method_mod_p, CRYPTO_LOCK_RSA, p, ctx))
- error = 1;
- if (!BN_MONT_CTX_set_locked
- (&rsa->_method_mod_q, CRYPTO_LOCK_RSA, q, ctx))
- error = 1;
- }
- /* clean up */
- if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
- BN_free(&local_p);
- BN_free(&local_q);
- }
- if (error)
- goto err;
- }
- if (rsa->flags & RSA_FLAG_CACHE_PUBLIC)
- if (!BN_MONT_CTX_set_locked
- (&rsa->_method_mod_n, CRYPTO_LOCK_RSA, rsa->n, ctx))
- goto err;
- /* compute I mod q */
- if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
- c = &local_c;
- BN_with_flags(c, I, BN_FLG_CONSTTIME);
- if (!BN_mod(r1, c, rsa->q, ctx))
- goto err;
- } else {
- if (!BN_mod(r1, I, rsa->q, ctx))
- goto err;
- }
- /* compute r1^dmq1 mod q */
- if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
- dmq1 = &local_dmq1;
- BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
- } else
- dmq1 = rsa->dmq1;
- if (!e_rsax_bn_mod_exp(m1, r1, dmq1, rsa->q, ctx,
- rsa->_method_mod_q, e_rsax_get_ctx(rsa, 0,
- rsa->q)))
- goto err;
- /* compute I mod p */
- if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
- c = &local_c;
- BN_with_flags(c, I, BN_FLG_CONSTTIME);
- if (!BN_mod(r1, c, rsa->p, ctx))
- goto err;
- } else {
- if (!BN_mod(r1, I, rsa->p, ctx))
- goto err;
- }
- /* compute r1^dmp1 mod p */
- if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
- dmp1 = &local_dmp1;
- BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
- } else
- dmp1 = rsa->dmp1;
- if (!e_rsax_bn_mod_exp(r0, r1, dmp1, rsa->p, ctx,
- rsa->_method_mod_p, e_rsax_get_ctx(rsa, 1,
- rsa->p)))
- goto err;
- if (!BN_sub(r0, r0, m1))
- goto err;
- /*
- * This will help stop the size of r0 increasing, which does affect the
- * multiply if it optimised for a power of 2 size
- */
- if (BN_is_negative(r0))
- if (!BN_add(r0, r0, rsa->p))
- goto err;
- if (!BN_mul(r1, r0, rsa->iqmp, ctx))
- goto err;
- /* Turn BN_FLG_CONSTTIME flag on before division operation */
- if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
- pr1 = &local_r1;
- BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
- } else
- pr1 = r1;
- if (!BN_mod(r0, pr1, rsa->p, ctx))
- goto err;
- /*
- * If p < q it is occasionally possible for the correction of adding 'p'
- * if r0 is negative above to leave the result still negative. This can
- * break the private key operations: the following second correction
- * should *always* correct this rare occurrence. This will *never* happen
- * with OpenSSL generated keys because they ensure p > q [steve]
- */
- if (BN_is_negative(r0))
- if (!BN_add(r0, r0, rsa->p))
- goto err;
- if (!BN_mul(r1, r0, rsa->q, ctx))
- goto err;
- if (!BN_add(r0, r1, m1))
- goto err;
- if (rsa->e && rsa->n) {
- if (!e_rsax_bn_mod_exp
- (vrfy, r0, rsa->e, rsa->n, ctx, rsa->_method_mod_n,
- e_rsax_get_ctx(rsa, 2, rsa->n)))
- goto err;
- /*
- * If 'I' was greater than (or equal to) rsa->n, the operation will
- * be equivalent to using 'I mod n'. However, the result of the
- * verify will *always* be less than 'n' so we don't check for
- * absolute equality, just congruency.
- */
- if (!BN_sub(vrfy, vrfy, I))
- goto err;
- if (!BN_mod(vrfy, vrfy, rsa->n, ctx))
- goto err;
- if (BN_is_negative(vrfy))
- if (!BN_add(vrfy, vrfy, rsa->n))
- goto err;
- if (!BN_is_zero(vrfy)) {
- /*
- * 'I' and 'vrfy' aren't congruent mod n. Don't leak
- * miscalculated CRT output, just do a raw (slower) mod_exp and
- * return that instead.
- */
- BIGNUM local_d;
- BIGNUM *d = NULL;
- if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
- d = &local_d;
- BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
- } else
- d = rsa->d;
- if (!e_rsax_bn_mod_exp(r0, I, d, rsa->n, ctx,
- rsa->_method_mod_n, e_rsax_get_ctx(rsa, 2,
- rsa->n)))
- goto err;
- }
- }
- ret = 1;
- err:
- BN_CTX_end(ctx);
- return ret;
- }
- # endif /* !OPENSSL_NO_RSA */
- #endif /* !COMPILE_RSAX */
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