diff options
Diffstat (limited to 'thirdparty/openssl/crypto/rsa/rsa_eay.c')
| -rw-r--r-- | thirdparty/openssl/crypto/rsa/rsa_eay.c | 904 |
1 files changed, 904 insertions, 0 deletions
diff --git a/thirdparty/openssl/crypto/rsa/rsa_eay.c b/thirdparty/openssl/crypto/rsa/rsa_eay.c new file mode 100644 index 0000000000..b147fff8bd --- /dev/null +++ b/thirdparty/openssl/crypto/rsa/rsa_eay.c @@ -0,0 +1,904 @@ +/* crypto/rsa/rsa_eay.c */ +/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) + * All rights reserved. + * + * This package is an SSL implementation written + * by Eric Young (eay@cryptsoft.com). + * The implementation was written so as to conform with Netscapes SSL. + * + * This library is free for commercial and non-commercial use as long as + * the following conditions are aheared to. The following conditions + * apply to all code found in this distribution, be it the RC4, RSA, + * lhash, DES, etc., code; not just the SSL code. The SSL documentation + * included with this distribution is covered by the same copyright terms + * except that the holder is Tim Hudson (tjh@cryptsoft.com). + * + * Copyright remains Eric Young's, and as such any Copyright notices in + * the code are not to be removed. + * If this package is used in a product, Eric Young should be given attribution + * as the author of the parts of the library used. + * This can be in the form of a textual message at program startup or + * in documentation (online or textual) provided with the package. + * + * 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 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 acknowledgement: + * "This product includes cryptographic software written by + * Eric Young (eay@cryptsoft.com)" + * The word 'cryptographic' can be left out if the rouines from the library + * being used are not cryptographic related :-). + * 4. If you include any Windows specific code (or a derivative thereof) from + * the apps directory (application code) you must include an acknowledgement: + * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" + * + * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND + * ANY EXPRESS 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 AUTHOR OR 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. + * + * The licence and distribution terms for any publically available version or + * derivative of this code cannot be changed. i.e. this code cannot simply be + * copied and put under another distribution licence + * [including the GNU Public Licence.] + */ +/* ==================================================================== + * Copyright (c) 1998-2006 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 + * openssl-core@openssl.org. + * + * 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 + * (eay@cryptsoft.com). This product includes software written by Tim + * Hudson (tjh@cryptsoft.com). + * + */ + +#include <stdio.h> +#include "cryptlib.h" +#include <openssl/bn.h> +#include <openssl/rsa.h> +#include <openssl/rand.h> + +#ifndef RSA_NULL + +static int RSA_eay_public_encrypt(int flen, const unsigned char *from, + unsigned char *to, RSA *rsa, int padding); +static int RSA_eay_private_encrypt(int flen, const unsigned char *from, + unsigned char *to, RSA *rsa, int padding); +static int RSA_eay_public_decrypt(int flen, const unsigned char *from, + unsigned char *to, RSA *rsa, int padding); +static int RSA_eay_private_decrypt(int flen, const unsigned char *from, + unsigned char *to, RSA *rsa, int padding); +static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa, + BN_CTX *ctx); +static int RSA_eay_init(RSA *rsa); +static int RSA_eay_finish(RSA *rsa); +static RSA_METHOD rsa_pkcs1_eay_meth = { + "Eric Young's PKCS#1 RSA", + RSA_eay_public_encrypt, + RSA_eay_public_decrypt, /* signature verification */ + RSA_eay_private_encrypt, /* signing */ + RSA_eay_private_decrypt, + RSA_eay_mod_exp, + BN_mod_exp_mont, /* XXX probably we should not use Montgomery + * if e == 3 */ + RSA_eay_init, + RSA_eay_finish, + 0, /* flags */ + NULL, + 0, /* rsa_sign */ + 0, /* rsa_verify */ + NULL /* rsa_keygen */ +}; + +const RSA_METHOD *RSA_PKCS1_SSLeay(void) +{ + return (&rsa_pkcs1_eay_meth); +} + +static int RSA_eay_public_encrypt(int flen, const unsigned char *from, + unsigned char *to, RSA *rsa, int padding) +{ + BIGNUM *f, *ret; + int i, j, k, num = 0, r = -1; + unsigned char *buf = NULL; + BN_CTX *ctx = NULL; + + if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS) { + RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_MODULUS_TOO_LARGE); + return -1; + } + + if (BN_ucmp(rsa->n, rsa->e) <= 0) { + RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE); + return -1; + } + + /* for large moduli, enforce exponent limit */ + if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS) { + if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS) { + RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE); + return -1; + } + } + + if ((ctx = BN_CTX_new()) == NULL) + goto err; + BN_CTX_start(ctx); + f = BN_CTX_get(ctx); + ret = BN_CTX_get(ctx); + num = BN_num_bytes(rsa->n); + buf = OPENSSL_malloc(num); + if (!f || !ret || !buf) { + RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, ERR_R_MALLOC_FAILURE); + goto err; + } + + switch (padding) { + case RSA_PKCS1_PADDING: + i = RSA_padding_add_PKCS1_type_2(buf, num, from, flen); + break; +# ifndef OPENSSL_NO_SHA + case RSA_PKCS1_OAEP_PADDING: + i = RSA_padding_add_PKCS1_OAEP(buf, num, from, flen, NULL, 0); + break; +# endif + case RSA_SSLV23_PADDING: + i = RSA_padding_add_SSLv23(buf, num, from, flen); + break; + case RSA_NO_PADDING: + i = RSA_padding_add_none(buf, num, from, flen); + break; + default: + RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_UNKNOWN_PADDING_TYPE); + goto err; + } + if (i <= 0) + goto err; + + if (BN_bin2bn(buf, num, f) == NULL) + goto err; + + if (BN_ucmp(f, rsa->n) >= 0) { + /* usually the padding functions would catch this */ + RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, + RSA_R_DATA_TOO_LARGE_FOR_MODULUS); + 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; + + if (!rsa->meth->bn_mod_exp(ret, f, rsa->e, rsa->n, ctx, + rsa->_method_mod_n)) + goto err; + + /* + * put in leading 0 bytes if the number is less than the length of the + * modulus + */ + j = BN_num_bytes(ret); + i = BN_bn2bin(ret, &(to[num - j])); + for (k = 0; k < (num - i); k++) + to[k] = 0; + + r = num; + err: + if (ctx != NULL) { + BN_CTX_end(ctx); + BN_CTX_free(ctx); + } + if (buf != NULL) { + OPENSSL_cleanse(buf, num); + OPENSSL_free(buf); + } + return (r); +} + +static BN_BLINDING *rsa_get_blinding(RSA *rsa, int *local, BN_CTX *ctx) +{ + BN_BLINDING *ret; + int got_write_lock = 0; + CRYPTO_THREADID cur; + + CRYPTO_r_lock(CRYPTO_LOCK_RSA); + + if (rsa->blinding == NULL) { + CRYPTO_r_unlock(CRYPTO_LOCK_RSA); + CRYPTO_w_lock(CRYPTO_LOCK_RSA); + got_write_lock = 1; + + if (rsa->blinding == NULL) + rsa->blinding = RSA_setup_blinding(rsa, ctx); + } + + ret = rsa->blinding; + if (ret == NULL) + goto err; + + CRYPTO_THREADID_current(&cur); + if (!CRYPTO_THREADID_cmp(&cur, BN_BLINDING_thread_id(ret))) { + /* rsa->blinding is ours! */ + + *local = 1; + } else { + /* resort to rsa->mt_blinding instead */ + + /* + * instructs rsa_blinding_convert(), rsa_blinding_invert() that the + * BN_BLINDING is shared, meaning that accesses require locks, and + * that the blinding factor must be stored outside the BN_BLINDING + */ + *local = 0; + + if (rsa->mt_blinding == NULL) { + if (!got_write_lock) { + CRYPTO_r_unlock(CRYPTO_LOCK_RSA); + CRYPTO_w_lock(CRYPTO_LOCK_RSA); + got_write_lock = 1; + } + + if (rsa->mt_blinding == NULL) + rsa->mt_blinding = RSA_setup_blinding(rsa, ctx); + } + ret = rsa->mt_blinding; + } + + err: + if (got_write_lock) + CRYPTO_w_unlock(CRYPTO_LOCK_RSA); + else + CRYPTO_r_unlock(CRYPTO_LOCK_RSA); + return ret; +} + +static int rsa_blinding_convert(BN_BLINDING *b, BIGNUM *f, BIGNUM *unblind, + BN_CTX *ctx) +{ + if (unblind == NULL) + /* + * Local blinding: store the unblinding factor in BN_BLINDING. + */ + return BN_BLINDING_convert_ex(f, NULL, b, ctx); + else { + /* + * Shared blinding: store the unblinding factor outside BN_BLINDING. + */ + int ret; + CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING); + ret = BN_BLINDING_convert_ex(f, unblind, b, ctx); + CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING); + return ret; + } +} + +static int rsa_blinding_invert(BN_BLINDING *b, BIGNUM *f, BIGNUM *unblind, + BN_CTX *ctx) +{ + /* + * For local blinding, unblind is set to NULL, and BN_BLINDING_invert_ex + * will use the unblinding factor stored in BN_BLINDING. If BN_BLINDING + * is shared between threads, unblind must be non-null: + * BN_BLINDING_invert_ex will then use the local unblinding factor, and + * will only read the modulus from BN_BLINDING. In both cases it's safe + * to access the blinding without a lock. + */ + return BN_BLINDING_invert_ex(f, unblind, b, ctx); +} + +/* signing */ +static int RSA_eay_private_encrypt(int flen, const unsigned char *from, + unsigned char *to, RSA *rsa, int padding) +{ + BIGNUM *f, *ret, *res; + int i, j, k, num = 0, r = -1; + unsigned char *buf = NULL; + BN_CTX *ctx = NULL; + int local_blinding = 0; + /* + * Used only if the blinding structure is shared. A non-NULL unblind + * instructs rsa_blinding_convert() and rsa_blinding_invert() to store + * the unblinding factor outside the blinding structure. + */ + BIGNUM *unblind = NULL; + BN_BLINDING *blinding = NULL; + + if ((ctx = BN_CTX_new()) == NULL) + goto err; + BN_CTX_start(ctx); + f = BN_CTX_get(ctx); + ret = BN_CTX_get(ctx); + num = BN_num_bytes(rsa->n); + buf = OPENSSL_malloc(num); + if (!f || !ret || !buf) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_MALLOC_FAILURE); + goto err; + } + + switch (padding) { + case RSA_PKCS1_PADDING: + i = RSA_padding_add_PKCS1_type_1(buf, num, from, flen); + break; + case RSA_X931_PADDING: + i = RSA_padding_add_X931(buf, num, from, flen); + break; + case RSA_NO_PADDING: + i = RSA_padding_add_none(buf, num, from, flen); + break; + case RSA_SSLV23_PADDING: + default: + RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, RSA_R_UNKNOWN_PADDING_TYPE); + goto err; + } + if (i <= 0) + goto err; + + if (BN_bin2bn(buf, num, f) == NULL) + goto err; + + if (BN_ucmp(f, rsa->n) >= 0) { + /* usually the padding functions would catch this */ + RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, + RSA_R_DATA_TOO_LARGE_FOR_MODULUS); + goto err; + } + + if (!(rsa->flags & RSA_FLAG_NO_BLINDING)) { + blinding = rsa_get_blinding(rsa, &local_blinding, ctx); + if (blinding == NULL) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR); + goto err; + } + } + + if (blinding != NULL) { + if (!local_blinding && ((unblind = BN_CTX_get(ctx)) == NULL)) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_MALLOC_FAILURE); + goto err; + } + if (!rsa_blinding_convert(blinding, f, unblind, ctx)) + goto err; + } + + if ((rsa->flags & RSA_FLAG_EXT_PKEY) || + ((rsa->p != NULL) && + (rsa->q != NULL) && + (rsa->dmp1 != NULL) && (rsa->dmq1 != NULL) && (rsa->iqmp != NULL))) { + if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) + goto err; + } else { + BIGNUM local_d; + BIGNUM *d = NULL; + + if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) { + BN_init(&local_d); + d = &local_d; + BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME); + } else + d = rsa->d; + + 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; + + if (!rsa->meth->bn_mod_exp(ret, f, d, rsa->n, ctx, + rsa->_method_mod_n)) + goto err; + } + + if (blinding) + if (!rsa_blinding_invert(blinding, ret, unblind, ctx)) + goto err; + + if (padding == RSA_X931_PADDING) { + BN_sub(f, rsa->n, ret); + if (BN_cmp(ret, f) > 0) + res = f; + else + res = ret; + } else + res = ret; + + /* + * put in leading 0 bytes if the number is less than the length of the + * modulus + */ + j = BN_num_bytes(res); + i = BN_bn2bin(res, &(to[num - j])); + for (k = 0; k < (num - i); k++) + to[k] = 0; + + r = num; + err: + if (ctx != NULL) { + BN_CTX_end(ctx); + BN_CTX_free(ctx); + } + if (buf != NULL) { + OPENSSL_cleanse(buf, num); + OPENSSL_free(buf); + } + return (r); +} + +static int RSA_eay_private_decrypt(int flen, const unsigned char *from, + unsigned char *to, RSA *rsa, int padding) +{ + BIGNUM *f, *ret; + int j, num = 0, r = -1; + unsigned char *p; + unsigned char *buf = NULL; + BN_CTX *ctx = NULL; + int local_blinding = 0; + /* + * Used only if the blinding structure is shared. A non-NULL unblind + * instructs rsa_blinding_convert() and rsa_blinding_invert() to store + * the unblinding factor outside the blinding structure. + */ + BIGNUM *unblind = NULL; + BN_BLINDING *blinding = NULL; + + if ((ctx = BN_CTX_new()) == NULL) + goto err; + BN_CTX_start(ctx); + f = BN_CTX_get(ctx); + ret = BN_CTX_get(ctx); + num = BN_num_bytes(rsa->n); + buf = OPENSSL_malloc(num); + if (!f || !ret || !buf) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_MALLOC_FAILURE); + goto err; + } + + /* + * This check was for equality but PGP does evil things and chops off the + * top '0' bytes + */ + if (flen > num) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, + RSA_R_DATA_GREATER_THAN_MOD_LEN); + goto err; + } + + /* make data into a big number */ + if (BN_bin2bn(from, (int)flen, f) == NULL) + goto err; + + if (BN_ucmp(f, rsa->n) >= 0) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, + RSA_R_DATA_TOO_LARGE_FOR_MODULUS); + goto err; + } + + if (!(rsa->flags & RSA_FLAG_NO_BLINDING)) { + blinding = rsa_get_blinding(rsa, &local_blinding, ctx); + if (blinding == NULL) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR); + goto err; + } + } + + if (blinding != NULL) { + if (!local_blinding && ((unblind = BN_CTX_get(ctx)) == NULL)) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_MALLOC_FAILURE); + goto err; + } + if (!rsa_blinding_convert(blinding, f, unblind, ctx)) + goto err; + } + + /* do the decrypt */ + if ((rsa->flags & RSA_FLAG_EXT_PKEY) || + ((rsa->p != NULL) && + (rsa->q != NULL) && + (rsa->dmp1 != NULL) && (rsa->dmq1 != NULL) && (rsa->iqmp != NULL))) { + if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) + goto err; + } else { + 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 (rsa->flags & RSA_FLAG_CACHE_PUBLIC) + if (!BN_MONT_CTX_set_locked + (&rsa->_method_mod_n, CRYPTO_LOCK_RSA, rsa->n, ctx)) + goto err; + if (!rsa->meth->bn_mod_exp(ret, f, d, rsa->n, ctx, + rsa->_method_mod_n)) + goto err; + } + + if (blinding) + if (!rsa_blinding_invert(blinding, ret, unblind, ctx)) + goto err; + + p = buf; + j = BN_bn2bin(ret, p); /* j is only used with no-padding mode */ + + switch (padding) { + case RSA_PKCS1_PADDING: + r = RSA_padding_check_PKCS1_type_2(to, num, buf, j, num); + break; +# ifndef OPENSSL_NO_SHA + case RSA_PKCS1_OAEP_PADDING: + r = RSA_padding_check_PKCS1_OAEP(to, num, buf, j, num, NULL, 0); + break; +# endif + case RSA_SSLV23_PADDING: + r = RSA_padding_check_SSLv23(to, num, buf, j, num); + break; + case RSA_NO_PADDING: + r = RSA_padding_check_none(to, num, buf, j, num); + break; + default: + RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, RSA_R_UNKNOWN_PADDING_TYPE); + goto err; + } + if (r < 0) + RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, RSA_R_PADDING_CHECK_FAILED); + + err: + if (ctx != NULL) { + BN_CTX_end(ctx); + BN_CTX_free(ctx); + } + if (buf != NULL) { + OPENSSL_cleanse(buf, num); + OPENSSL_free(buf); + } + return (r); +} + +/* signature verification */ +static int RSA_eay_public_decrypt(int flen, const unsigned char *from, + unsigned char *to, RSA *rsa, int padding) +{ + BIGNUM *f, *ret; + int i, num = 0, r = -1; + unsigned char *p; + unsigned char *buf = NULL; + BN_CTX *ctx = NULL; + + if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS) { + RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_MODULUS_TOO_LARGE); + return -1; + } + + if (BN_ucmp(rsa->n, rsa->e) <= 0) { + RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE); + return -1; + } + + /* for large moduli, enforce exponent limit */ + if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS) { + if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS) { + RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE); + return -1; + } + } + + if ((ctx = BN_CTX_new()) == NULL) + goto err; + BN_CTX_start(ctx); + f = BN_CTX_get(ctx); + ret = BN_CTX_get(ctx); + num = BN_num_bytes(rsa->n); + buf = OPENSSL_malloc(num); + if (!f || !ret || !buf) { + RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, ERR_R_MALLOC_FAILURE); + goto err; + } + + /* + * This check was for equality but PGP does evil things and chops off the + * top '0' bytes + */ + if (flen > num) { + RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_DATA_GREATER_THAN_MOD_LEN); + goto err; + } + + if (BN_bin2bn(from, flen, f) == NULL) + goto err; + + if (BN_ucmp(f, rsa->n) >= 0) { + RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, + RSA_R_DATA_TOO_LARGE_FOR_MODULUS); + 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; + + if (!rsa->meth->bn_mod_exp(ret, f, rsa->e, rsa->n, ctx, + rsa->_method_mod_n)) + goto err; + + if ((padding == RSA_X931_PADDING) && ((ret->d[0] & 0xf) != 12)) + if (!BN_sub(ret, rsa->n, ret)) + goto err; + + p = buf; + i = BN_bn2bin(ret, p); + + switch (padding) { + case RSA_PKCS1_PADDING: + r = RSA_padding_check_PKCS1_type_1(to, num, buf, i, num); + break; + case RSA_X931_PADDING: + r = RSA_padding_check_X931(to, num, buf, i, num); + break; + case RSA_NO_PADDING: + r = RSA_padding_check_none(to, num, buf, i, num); + break; + default: + RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_UNKNOWN_PADDING_TYPE); + goto err; + } + if (r < 0) + RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_PADDING_CHECK_FAILED); + + err: + if (ctx != NULL) { + BN_CTX_end(ctx); + BN_CTX_free(ctx); + } + if (buf != NULL) { + OPENSSL_cleanse(buf, num); + OPENSSL_free(buf); + } + return (r); +} + +static int RSA_eay_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; + + /* + * 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)) + goto err; + if (!BN_MONT_CTX_set_locked + (&rsa->_method_mod_q, CRYPTO_LOCK_RSA, q, ctx)) + 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 (!rsa->meth->bn_mod_exp(m1, r1, dmq1, rsa->q, ctx, rsa->_method_mod_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 (!rsa->meth->bn_mod_exp(r0, r1, dmp1, rsa->p, ctx, rsa->_method_mod_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 (!rsa->meth->bn_mod_exp(vrfy, r0, rsa->e, rsa->n, ctx, + rsa->_method_mod_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 (!rsa->meth->bn_mod_exp(r0, I, d, rsa->n, ctx, + rsa->_method_mod_n)) + goto err; + } + } + ret = 1; + err: + BN_CTX_end(ctx); + return (ret); +} + +static int RSA_eay_init(RSA *rsa) +{ + rsa->flags |= RSA_FLAG_CACHE_PUBLIC | RSA_FLAG_CACHE_PRIVATE; + return (1); +} + +static int RSA_eay_finish(RSA *rsa) +{ + if (rsa->_method_mod_n != NULL) + BN_MONT_CTX_free(rsa->_method_mod_n); + if (rsa->_method_mod_p != NULL) + BN_MONT_CTX_free(rsa->_method_mod_p); + if (rsa->_method_mod_q != NULL) + BN_MONT_CTX_free(rsa->_method_mod_q); + return (1); +} + +#endif |