X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=crypto%2Frsa%2Frsa_eay.c;h=7f58a8989107ca39824e1f939960aa119db077da;hp=4525e6676c4d6f2edbdbfaf411341cf4a8e41ca3;hb=94fd382f8b4abdc3e65e5be584b76c2b37017d7a;hpb=79df9d62721467927c81f1fa91568340e873ee9c diff --git a/crypto/rsa/rsa_eay.c b/crypto/rsa/rsa_eay.c index 4525e6676c..7f58a89891 100644 --- a/crypto/rsa/rsa_eay.c +++ b/crypto/rsa/rsa_eay.c @@ -55,6 +55,59 @@ * 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 #include "cryptlib.h" @@ -62,49 +115,88 @@ #include #include -static int RSA_eay_public_encrypt(int flen, unsigned char *from, +#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, unsigned char *from, +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, unsigned char *from, +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, unsigned char *from, +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, BIGNUM *i, RSA *rsa); +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, - RSA_eay_private_encrypt, + RSA_eay_public_decrypt, /* signature verification */ + RSA_eay_private_encrypt, /* signing */ RSA_eay_private_decrypt, RSA_eay_mod_exp, - BN_mod_exp_mont, + BN_mod_exp_mont, /* XXX probably we should not use Montgomery if e == 3 */ RSA_eay_init, RSA_eay_finish, - 0, + 0, /* flags */ NULL, + 0, /* rsa_sign */ + 0, /* rsa_verify */ + NULL /* rsa_keygen */ }; -RSA_METHOD *RSA_PKCS1_SSLeay(void) +const RSA_METHOD *RSA_PKCS1_SSLeay(void) { return(&rsa_pkcs1_eay_meth); } -static int RSA_eay_public_encrypt(int flen, unsigned char *from, +/* Usage example; + * MONT_HELPER(rsa->_method_mod_p, bn_ctx, rsa->p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err); + */ +#define MONT_HELPER(method_mod, ctx, m, pre_cond, err_instr) \ + if ((pre_cond) && ((method_mod) == NULL) && \ + !BN_MONT_CTX_set_locked(&(method_mod), \ + CRYPTO_LOCK_RSA, \ + (m), (ctx))) \ + err_instr + +static int RSA_eay_public_encrypt(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, int padding) { - BIGNUM f,ret; + BIGNUM *f,*ret; int i,j,k,num=0,r= -1; unsigned char *buf=NULL; BN_CTX *ctx=NULL; - BN_init(&f); - BN_init(&ret); + 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); - if ((buf=(unsigned char *)Malloc(num)) == NULL) + buf = OPENSSL_malloc(num); + if (!f || !ret || !buf) { RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE); goto err; @@ -115,7 +207,7 @@ static int RSA_eay_public_encrypt(int flen, unsigned char *from, case RSA_PKCS1_PADDING: i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen); break; -#ifndef NO_SHA +#ifndef OPENSSL_NO_SHA case RSA_PKCS1_OAEP_PADDING: i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0); break; @@ -132,52 +224,153 @@ static int RSA_eay_public_encrypt(int flen, unsigned char *from, } if (i <= 0) goto err; - if (BN_bin2bn(buf,num,&f) == NULL) goto err; + if (BN_bin2bn(buf,num,f) == NULL) goto err; - if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC)) + if (BN_ucmp(f, rsa->n) >= 0) { - if ((rsa->_method_mod_n=BN_MONT_CTX_new()) != NULL) - if (!BN_MONT_CTX_set(rsa->_method_mod_n,rsa->n,ctx)) - goto err; + /* 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->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx, + MONT_HELPER(rsa->_method_mod_n, ctx, rsa->n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, 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])); + 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_free(ctx); - BN_clear_free(&f); - BN_clear_free(&ret); + if (ctx != NULL) + { + BN_CTX_end(ctx); + BN_CTX_free(ctx); + } if (buf != NULL) { - memset(buf,0,num); - Free(buf); + OPENSSL_cleanse(buf,num); + OPENSSL_free(buf); } return(r); } -static int RSA_eay_private_encrypt(int flen, unsigned char *from, +static BN_BLINDING *rsa_get_blinding(RSA *rsa, int *local, BN_CTX *ctx) +{ + BN_BLINDING *ret; + CRYPTO_THREADID tid; + int got_write_lock = 0; + + CRYPTO_THREADID_set(&tid); + 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; + + if (!BN_BLINDING_cmp_thread(ret, &tid)) + { + /* rsa->blinding is ours! */ + + *local = 1; + } + else + { + /* resort to rsa->mt_blinding instead */ + + *local = 0; /* 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 + */ + + 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, int local, BIGNUM *f, + BIGNUM *r, BN_CTX *ctx) +{ + if (local) + return BN_BLINDING_convert_ex(f, NULL, b, ctx); + else + { + int ret; + CRYPTO_r_lock(CRYPTO_LOCK_RSA_BLINDING); + ret = BN_BLINDING_convert_ex(f, r, b, ctx); + CRYPTO_r_unlock(CRYPTO_LOCK_RSA_BLINDING); + return ret; + } +} + +static int rsa_blinding_invert(BN_BLINDING *b, int local, BIGNUM *f, + BIGNUM *r, BN_CTX *ctx) +{ + if (local) + return BN_BLINDING_invert_ex(f, NULL, b, ctx); + else + { + int ret; + CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING); + ret = BN_BLINDING_invert_ex(f, r, b, ctx); + CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING); + return ret; + } +} + +/* signing */ +static int RSA_eay_private_encrypt(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, int padding) { - BIGNUM f,ret; + BIGNUM *f, *ret, *br, *res; int i,j,k,num=0,r= -1; unsigned char *buf=NULL; BN_CTX *ctx=NULL; - - BN_init(&f); - BN_init(&ret); + int local_blinding = 0; + BN_BLINDING *blinding = NULL; if ((ctx=BN_CTX_new()) == NULL) goto err; - num=BN_num_bytes(rsa->n); - if ((buf=(unsigned char *)Malloc(num)) == NULL) + BN_CTX_start(ctx); + f = BN_CTX_get(ctx); + br = 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; @@ -188,6 +381,9 @@ static int RSA_eay_private_encrypt(int flen, unsigned char *from, 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; @@ -198,70 +394,120 @@ static int RSA_eay_private_encrypt(int flen, unsigned char *from, } if (i <= 0) goto err; - if (BN_bin2bn(buf,num,&f) == NULL) 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_BLINDING) && (rsa->blinding == NULL)) - RSA_blinding_on(rsa,ctx); - if (rsa->flags & RSA_FLAG_BLINDING) - if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) 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 (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx)) + goto err; - if ( (rsa->p != NULL) && + 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)) goto err; } + (rsa->iqmp != NULL)) ) + { + if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err; + } else { - if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL)) goto err; + 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; + + MONT_HELPER(rsa->_method_mod_n, ctx, rsa->n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err); + + if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx, + rsa->_method_mod_n)) goto err; } - if (rsa->flags & RSA_FLAG_BLINDING) - if (!BN_BLINDING_invert(&ret,rsa->blinding,ctx)) goto err; + if (blinding) + if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx)) + goto err; + + if (padding == RSA_X931_PADDING) + { + BN_sub(f, rsa->n, ret); + if (BN_cmp(ret, f)) + 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(&ret); - i=BN_bn2bin(&ret,&(to[num-j])); + 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_free(ctx); - BN_clear_free(&ret); - BN_clear_free(&f); + if (ctx != NULL) + { + BN_CTX_end(ctx); + BN_CTX_free(ctx); + } if (buf != NULL) { - memset(buf,0,num); - Free(buf); + OPENSSL_cleanse(buf,num); + OPENSSL_free(buf); } return(r); } -static int RSA_eay_private_decrypt(int flen, unsigned char *from, +static int RSA_eay_private_decrypt(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, int padding) { - BIGNUM f,ret; + BIGNUM *f, *ret, *br; int j,num=0,r= -1; unsigned char *p; unsigned char *buf=NULL; BN_CTX *ctx=NULL; - - BN_init(&f); - BN_init(&ret); - ctx=BN_CTX_new(); - if (ctx == NULL) goto err; - - num=BN_num_bytes(rsa->n); - - if ((buf=(unsigned char *)Malloc(num)) == NULL) + int local_blinding = 0; + BN_BLINDING *blinding = NULL; + + if((ctx = BN_CTX_new()) == NULL) goto err; + BN_CTX_start(ctx); + f = BN_CTX_get(ctx); + br = 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 equallity but PGP does evil things + /* This check was for equality but PGP does evil things * and chops off the top '0' bytes */ if (flen > num) { @@ -270,38 +516,70 @@ static int RSA_eay_private_decrypt(int flen, unsigned char *from, } /* make data into a big number */ - if (BN_bin2bn(from,(int)flen,&f) == NULL) goto err; + if (BN_bin2bn(from,(int)flen,f) == NULL) goto err; - if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL)) - RSA_blinding_on(rsa,ctx); - if (rsa->flags & RSA_FLAG_BLINDING) - if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) 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 (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx)) + goto err; /* do the decrypt */ - if ( (rsa->p != NULL) && + 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)) goto err; } + (rsa->iqmp != NULL)) ) + { + if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err; + } else { - if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL)) - goto err; + 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; + + MONT_HELPER(rsa->_method_mod_n, ctx, rsa->n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err); + if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx, + rsa->_method_mod_n)) + goto err; } - if (rsa->flags & RSA_FLAG_BLINDING) - if (!BN_BLINDING_invert(&ret,rsa->blinding,ctx)) goto err; + if (blinding) + if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx)) + goto err; p=buf; - j=BN_bn2bin(&ret,p); /* j is only used with no-padding mode */ + 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 NO_SHA +#ifndef OPENSSL_NO_SHA case RSA_PKCS1_OAEP_PADDING: r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0); break; @@ -320,40 +598,64 @@ static int RSA_eay_private_decrypt(int flen, unsigned char *from, RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED); err: - if (ctx != NULL) BN_CTX_free(ctx); - BN_clear_free(&f); - BN_clear_free(&ret); + if (ctx != NULL) + { + BN_CTX_end(ctx); + BN_CTX_free(ctx); + } if (buf != NULL) { - memset(buf,0,num); - Free(buf); + OPENSSL_cleanse(buf,num); + OPENSSL_free(buf); } return(r); } -static int RSA_eay_public_decrypt(int flen, unsigned char *from, +/* signature verification */ +static int RSA_eay_public_decrypt(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, int padding) { - BIGNUM f,ret; + BIGNUM *f,*ret; int i,num=0,r= -1; unsigned char *p; unsigned char *buf=NULL; BN_CTX *ctx=NULL; - BN_init(&f); - BN_init(&ret); - ctx=BN_CTX_new(); - if (ctx == NULL) goto err; + 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=(unsigned char *)Malloc(num); - if (buf == NULL) + 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 equallity but PGP does evil things + /* This check was for equality but PGP does evil things * and chops off the top '0' bytes */ if (flen > num) { @@ -361,26 +663,33 @@ static int RSA_eay_public_decrypt(int flen, unsigned char *from, goto err; } - if (BN_bin2bn(from,flen,&f) == NULL) goto err; - /* do the decrypt */ - if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC)) + if (BN_bin2bn(from,flen,f) == NULL) goto err; + + if (BN_ucmp(f, rsa->n) >= 0) { - if ((rsa->_method_mod_n=BN_MONT_CTX_new()) != NULL) - if (!BN_MONT_CTX_set(rsa->_method_mod_n,rsa->n,ctx)) - goto err; + RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS); + goto err; } - if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx, + MONT_HELPER(rsa->_method_mod_n, ctx, rsa->n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, 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)) + BN_sub(ret, rsa->n, ret); + p=buf; - i=BN_bn2bin(&ret,p); + 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; @@ -392,61 +701,124 @@ static int RSA_eay_public_decrypt(int flen, unsigned char *from, RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED); err: - if (ctx != NULL) BN_CTX_free(ctx); - BN_clear_free(&f); - BN_clear_free(&ret); + if (ctx != NULL) + { + BN_CTX_end(ctx); + BN_CTX_free(ctx); + } if (buf != NULL) { - memset(buf,0,num); - Free(buf); + OPENSSL_cleanse(buf,num); + OPENSSL_free(buf); } return(r); } -static int RSA_eay_mod_exp(BIGNUM *r0, BIGNUM *I, RSA *rsa) +static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx) { - BIGNUM r1,m1; + BIGNUM *r1,*m1,*vrfy; + BIGNUM local_dmp1,local_dmq1,local_c,local_r1; + BIGNUM *dmp1,*dmq1,*c,*pr1; int ret=0; - BN_CTX *ctx; - if ((ctx=BN_CTX_new()) == NULL) goto err; - BN_init(&m1); - BN_init(&r1); + BN_CTX_start(ctx); + r1 = BN_CTX_get(ctx); + m1 = BN_CTX_get(ctx); + vrfy = BN_CTX_get(ctx); - if (rsa->flags & RSA_FLAG_CACHE_PRIVATE) - { - if (rsa->_method_mod_p == NULL) + { + 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)) { - if ((rsa->_method_mod_p=BN_MONT_CTX_new()) != NULL) - if (!BN_MONT_CTX_set(rsa->_method_mod_p,rsa->p, - ctx)) - goto err; + 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); } - if (rsa->_method_mod_q == NULL) + else { - if ((rsa->_method_mod_q=BN_MONT_CTX_new()) != NULL) - if (!BN_MONT_CTX_set(rsa->_method_mod_q,rsa->q, - ctx)) - goto err; + p = rsa->p; + q = rsa->q; } + + MONT_HELPER(rsa->_method_mod_p, ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err); + MONT_HELPER(rsa->_method_mod_q, ctx, q, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err); + } + + MONT_HELPER(rsa->_method_mod_n, ctx, rsa->n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, 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; } - if (!BN_mod(&r1,I,rsa->q,ctx)) goto err; - if (!rsa->meth->bn_mod_exp(&m1,&r1,rsa->dmq1,rsa->q,ctx, + /* 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; - if (!BN_mod(&r1,I,rsa->p,ctx)) goto err; - if (!rsa->meth->bn_mod_exp(r0,&r1,rsa->dmp1,rsa->p,ctx, + /* 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; + 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 (r0->neg) + if (BN_is_negative(r0)) if (!BN_add(r0,r0,rsa->p)) goto err; - if (!BN_mul(&r1,r0,rsa->iqmp,ctx)) goto err; - if (!BN_mod(r0,&r1,rsa->p,ctx)) 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 @@ -454,16 +826,45 @@ static int RSA_eay_mod_exp(BIGNUM *r0, BIGNUM *I, RSA *rsa) * This will *never* happen with OpenSSL generated keys because * they ensure p > q [steve] */ - if (r0->neg) + 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 (!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_clear_free(&m1); - BN_clear_free(&r1); - BN_CTX_free(ctx); + BN_CTX_end(ctx); return(ret); } @@ -484,4 +885,4 @@ static int RSA_eay_finish(RSA *rsa) return(1); } - +#endif