BN_BLINDING *RSA_setup_blinding(RSA *rsa, BN_CTX *in_ctx)
{
BIGNUM local_n;
BIGNUM *e,*n;
BN_CTX *ctx;
BN_BLINDING *ret = NULL;
if (in_ctx == NULL)
{
if ((ctx = BN_CTX_new()) == NULL) return 0;
}
else
ctx = in_ctx;
BN_CTX_start(ctx);
e = BN_CTX_get(ctx);
if (e == NULL)
{
RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_MALLOC_FAILURE);
goto err;
}
if (rsa->e == NULL)
{
e = rsa_get_public_exp(rsa->d, rsa->p, rsa->q, ctx);
if (e == NULL)
{
RSAerr(RSA_F_RSA_SETUP_BLINDING, RSA_R_NO_PUBLIC_EXPONENT);
goto err;
}
}
else
e = rsa->e;
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
{
/* Set BN_FLG_CONSTTIME flag */
n = &local_n;
BN_with_flags(n, rsa->n, BN_FLG_CONSTTIME);
}
else
n = rsa->n;
ret = BN_BLINDING_create_param(NULL, e, n, ctx,
rsa->meth->bn_mod_exp, rsa->_method_mod_n);
if (ret == NULL)
{
RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_BN_LIB);
goto err;
}
CRYPTO_THREADID_current(BN_BLINDING_thread_id(ret));
err:
BN_CTX_end(ctx);
if (in_ctx == NULL)
BN_CTX_free(ctx);
if(rsa->e == NULL)
BN_free(e);
return ret;
}
BN_BLINDING *rsa_setup_blinding(RSA *rsa, BN_CTX *in_ctx) {
BIGNUM local_n;
BIGNUM *e, *n;
BN_CTX *ctx;
BN_BLINDING *ret = NULL;
BN_MONT_CTX *mont_ctx = NULL;
if (in_ctx == NULL) {
ctx = BN_CTX_new();
if (ctx == NULL) {
return 0;
}
} else {
ctx = in_ctx;
}
BN_CTX_start(ctx);
e = BN_CTX_get(ctx);
if (e == NULL) {
OPENSSL_PUT_ERROR(RSA, ERR_R_MALLOC_FAILURE);
goto err;
}
if (rsa->e == NULL) {
e = rsa_get_public_exp(rsa->d, rsa->p, rsa->q, ctx);
if (e == NULL) {
OPENSSL_PUT_ERROR(RSA, RSA_R_NO_PUBLIC_EXPONENT);
goto err;
}
} else {
e = rsa->e;
}
n = &local_n;
BN_with_flags(n, rsa->n, BN_FLG_CONSTTIME);
if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) {
mont_ctx = BN_MONT_CTX_set_locked(&rsa->mont_n, &rsa->lock, rsa->n, ctx);
if (mont_ctx == NULL) {
goto err;
}
}
ret = BN_BLINDING_create_param(NULL, e, n, ctx, mont_ctx);
if (ret == NULL) {
OPENSSL_PUT_ERROR(RSA, ERR_R_BN_LIB);
goto err;
}
err:
BN_CTX_end(ctx);
if (in_ctx == NULL) {
BN_CTX_free(ctx);
}
if (rsa->e == NULL) {
BN_free(e);
}
return ret;
}
BN_BLINDING *RSA_setup_blinding(RSA *rsa, BN_CTX *in_ctx)
{
BIGNUM local_n;
BIGNUM *e, *n;
BN_CTX *ctx;
BN_BLINDING *ret = NULL;
if (in_ctx == NULL) {
if ((ctx = BN_CTX_new()) == NULL)
return 0;
} else
ctx = in_ctx;
BN_CTX_start(ctx);
e = BN_CTX_get(ctx);
if (e == NULL) {
RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_MALLOC_FAILURE);
goto err;
}
if (rsa->e == NULL) {
e = rsa_get_public_exp(rsa->d, rsa->p, rsa->q, ctx);
if (e == NULL) {
RSAerr(RSA_F_RSA_SETUP_BLINDING, RSA_R_NO_PUBLIC_EXPONENT);
goto err;
}
} else
e = rsa->e;
if ((RAND_status() == 0) && rsa->d != NULL && rsa->d->d != NULL) {
/*
* if PRNG is not properly seeded, resort to secret exponent as
* unpredictable seed
*/
RAND_add(rsa->d->d, rsa->d->dmax * sizeof rsa->d->d[0], 0.0);
}
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
/* Set BN_FLG_CONSTTIME flag */
n = &local_n;
BN_with_flags(n, rsa->n, BN_FLG_CONSTTIME);
} else
n = rsa->n;
ret = BN_BLINDING_create_param(NULL, e, n, ctx,
rsa->meth->bn_mod_exp, rsa->_method_mod_n);
if (ret == NULL) {
RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_BN_LIB);
goto err;
}
CRYPTO_THREADID_current(BN_BLINDING_thread_id(ret));
err:
BN_CTX_end(ctx);
if (in_ctx == NULL)
BN_CTX_free(ctx);
if (rsa->e == NULL)
BN_free(e);
return ret;
}
BN_BLINDING *RSA_setup_blinding(RSA *rsa, BN_CTX *in_ctx)
{
BIGNUM *e;
BN_CTX *ctx;
BN_BLINDING *ret = NULL;
if (in_ctx == NULL) {
if ((ctx = BN_CTX_new()) == NULL)
return 0;
} else
ctx = in_ctx;
BN_CTX_start(ctx);
e = BN_CTX_get(ctx);
if (e == NULL) {
RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_MALLOC_FAILURE);
goto err;
}
if (rsa->e == NULL) {
e = rsa_get_public_exp(rsa->d, rsa->p, rsa->q, ctx);
if (e == NULL) {
RSAerr(RSA_F_RSA_SETUP_BLINDING, RSA_R_NO_PUBLIC_EXPONENT);
goto err;
}
} else
e = rsa->e;
{
BIGNUM *n = BN_new();
if (n == NULL) {
RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_MALLOC_FAILURE);
goto err;
}
BN_with_flags(n, rsa->n, BN_FLG_CONSTTIME);
ret = BN_BLINDING_create_param(NULL, e, n, ctx, rsa->meth->bn_mod_exp,
rsa->_method_mod_n);
/* We MUST free n before any further use of rsa->n */
BN_free(n);
}
if (ret == NULL) {
RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_BN_LIB);
goto err;
}
BN_BLINDING_set_current_thread(ret);
err:
BN_CTX_end(ctx);
if (ctx != in_ctx)
BN_CTX_free(ctx);
if (e != rsa->e)
BN_free(e);
return ret;
}
static int dsa_builtin_keygen(DSA *dsa)
{
int ok = 0;
BN_CTX *ctx = NULL;
BIGNUM *pub_key = NULL, *priv_key = NULL;
if ((ctx = BN_CTX_new()) == NULL)
goto err;
if (dsa->priv_key == NULL) {
if ((priv_key = BN_secure_new()) == NULL)
goto err;
} else
priv_key = dsa->priv_key;
do
if (!BN_rand_range(priv_key, dsa->q))
goto err;
while (BN_is_zero(priv_key)) ;
if (dsa->pub_key == NULL) {
if ((pub_key = BN_new()) == NULL)
goto err;
} else
pub_key = dsa->pub_key;
{
BIGNUM *local_prk = NULL;
BIGNUM *prk;
if ((dsa->flags & DSA_FLAG_NO_EXP_CONSTTIME) == 0) {
local_prk = prk = BN_new();
if (!local_prk)
goto err;
BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
} else
prk = priv_key;
if (!BN_mod_exp(pub_key, dsa->g, prk, dsa->p, ctx)) {
BN_free(local_prk);
goto err;
}
BN_free(local_prk);
}
dsa->priv_key = priv_key;
dsa->pub_key = pub_key;
ok = 1;
err:
if (pub_key != dsa->pub_key)
BN_free(pub_key);
if (priv_key != dsa->priv_key)
BN_free(priv_key);
BN_CTX_free(ctx);
return (ok);
}
int rsa_default_private_transform(RSA *rsa, uint8_t *out, const uint8_t *in,
size_t len) {
BIGNUM *f, *result;
BN_CTX *ctx = NULL;
unsigned blinding_index = 0;
BN_BLINDING *blinding = NULL;
int ret = 0;
ctx = BN_CTX_new();
if (ctx == NULL) {
goto err;
}
BN_CTX_start(ctx);
f = BN_CTX_get(ctx);
result = BN_CTX_get(ctx);
if (f == NULL || result == NULL) {
OPENSSL_PUT_ERROR(RSA, ERR_R_MALLOC_FAILURE);
goto err;
}
if (BN_bin2bn(in, len, f) == NULL) {
goto err;
}
if (BN_ucmp(f, rsa->n) >= 0) {
/* Usually the padding functions would catch this. */
OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
goto err;
}
if (!BN_MONT_CTX_set_locked(&rsa->mont_n, &rsa->lock, rsa->n, ctx)) {
OPENSSL_PUT_ERROR(RSA, ERR_R_INTERNAL_ERROR);
goto err;
}
/* We cannot do blinding or verification without |e|, and continuing without
* those countermeasures is dangerous. However, the Java/Android RSA API
* requires support for keys where only |d| and |n| (and not |e|) are known.
* The callers that require that bad behavior set |RSA_FLAG_NO_BLINDING|. */
int disable_security = (rsa->flags & RSA_FLAG_NO_BLINDING) && rsa->e == NULL;
if (!disable_security) {
/* Keys without public exponents must have blinding explicitly disabled to
* be used. */
if (rsa->e == NULL) {
OPENSSL_PUT_ERROR(RSA, RSA_R_NO_PUBLIC_EXPONENT);
goto err;
}
blinding = rsa_blinding_get(rsa, &blinding_index, ctx);
if (blinding == NULL) {
OPENSSL_PUT_ERROR(RSA, ERR_R_INTERNAL_ERROR);
goto err;
}
if (!BN_BLINDING_convert(f, blinding, rsa->e, rsa->mont_n, ctx)) {
goto err;
}
}
if (rsa->p != NULL && rsa->q != NULL && rsa->e != NULL && rsa->dmp1 != NULL &&
rsa->dmq1 != NULL && rsa->iqmp != NULL) {
if (!mod_exp(result, f, rsa, ctx)) {
goto err;
}
} else {
BIGNUM local_d;
BIGNUM *d = NULL;
BN_init(&local_d);
d = &local_d;
BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
if (!BN_mod_exp_mont_consttime(result, f, d, rsa->n, ctx, rsa->mont_n)) {
goto err;
}
}
/* Verify the result to protect against fault attacks as described in the
* 1997 paper "On the Importance of Checking Cryptographic Protocols for
* Faults" by Dan Boneh, Richard A. DeMillo, and Richard J. Lipton. Some
* implementations do this only when the CRT is used, but we do it in all
* cases. Section 6 of the aforementioned paper describes an attack that
* works when the CRT isn't used. That attack is much less likely to succeed
* than the CRT attack, but there have likely been improvements since 1997.
*
* This check is cheap assuming |e| is small; it almost always is. */
if (!disable_security) {
BIGNUM *vrfy = BN_CTX_get(ctx);
if (vrfy == NULL ||
!BN_mod_exp_mont(vrfy, result, rsa->e, rsa->n, ctx, rsa->mont_n) ||
!BN_equal_consttime(vrfy, f)) {
OPENSSL_PUT_ERROR(RSA, ERR_R_INTERNAL_ERROR);
goto err;
}
if (!BN_BLINDING_invert(result, blinding, rsa->mont_n, ctx)) {
goto err;
}
}
if (!BN_bn2bin_padded(out, len, result)) {
OPENSSL_PUT_ERROR(RSA, ERR_R_INTERNAL_ERROR);
goto err;
}
ret = 1;
err:
if (ctx != NULL) {
BN_CTX_end(ctx);
BN_CTX_free(ctx);
}
if (blinding != NULL) {
rsa_blinding_release(rsa, blinding, blinding_index);
}
return ret;
}
static int mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx) {
assert(ctx != NULL);
assert(rsa->n != NULL);
assert(rsa->e != NULL);
assert(rsa->d != NULL);
assert(rsa->p != NULL);
assert(rsa->q != NULL);
assert(rsa->dmp1 != NULL);
assert(rsa->dmq1 != NULL);
assert(rsa->iqmp != NULL);
BIGNUM *r1, *m1, *vrfy;
BIGNUM local_dmp1, local_dmq1, local_c, local_r1;
BIGNUM *dmp1, *dmq1, *c, *pr1;
int ret = 0;
size_t i, num_additional_primes = 0;
if (rsa->additional_primes != NULL) {
num_additional_primes = sk_RSA_additional_prime_num(rsa->additional_primes);
}
BN_CTX_start(ctx);
r1 = BN_CTX_get(ctx);
m1 = BN_CTX_get(ctx);
vrfy = BN_CTX_get(ctx);
if (r1 == NULL ||
m1 == NULL ||
vrfy == NULL) {
goto err;
}
{
BIGNUM local_p, local_q;
BIGNUM *p = NULL, *q = NULL;
/* Make sure BN_mod in Montgomery initialization uses BN_FLG_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);
if (!BN_MONT_CTX_set_locked(&rsa->mont_p, &rsa->lock, p, ctx) ||
!BN_MONT_CTX_set_locked(&rsa->mont_q, &rsa->lock, q, ctx)) {
goto err;
}
}
if (!BN_MONT_CTX_set_locked(&rsa->mont_n, &rsa->lock, rsa->n, ctx)) {
goto err;
}
/* compute I mod q */
c = &local_c;
BN_with_flags(c, I, BN_FLG_CONSTTIME);
if (!BN_mod(r1, c, rsa->q, ctx)) {
goto err;
}
/* compute r1^dmq1 mod q */
dmq1 = &local_dmq1;
BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
if (!BN_mod_exp_mont_consttime(m1, r1, dmq1, rsa->q, ctx, rsa->mont_q)) {
goto err;
}
/* compute I mod p */
c = &local_c;
BN_with_flags(c, I, BN_FLG_CONSTTIME);
if (!BN_mod(r1, c, rsa->p, ctx)) {
goto err;
}
/* compute r1^dmp1 mod p */
dmp1 = &local_dmp1;
BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
if (!BN_mod_exp_mont_consttime(r0, r1, dmp1, rsa->p, ctx, rsa->mont_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 */
pr1 = &local_r1;
BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
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;
}
for (i = 0; i < num_additional_primes; i++) {
/* multi-prime RSA. */
BIGNUM local_exp, local_prime;
BIGNUM *exp = &local_exp, *prime = &local_prime;
RSA_additional_prime *ap =
sk_RSA_additional_prime_value(rsa->additional_primes, i);
BN_with_flags(exp, ap->exp, BN_FLG_CONSTTIME);
BN_with_flags(prime, ap->prime, BN_FLG_CONSTTIME);
/* c will already point to a BIGNUM with the correct flags. */
if (!BN_mod(r1, c, prime, ctx)) {
goto err;
}
if (!BN_MONT_CTX_set_locked(&ap->mont, &rsa->lock, prime, ctx) ||
!BN_mod_exp_mont_consttime(m1, r1, exp, prime, ctx, ap->mont)) {
goto err;
}
BN_set_flags(m1, BN_FLG_CONSTTIME);
if (!BN_sub(m1, m1, r0) ||
!BN_mul(m1, m1, ap->coeff, ctx) ||
!BN_mod(m1, m1, prime, ctx) ||
(BN_is_negative(m1) && !BN_add(m1, m1, prime)) ||
!BN_mul(m1, m1, ap->r, ctx) ||
!BN_add(r0, r0, m1)) {
goto err;
}
}
ret = 1;
err:
BN_CTX_end(ctx);
return ret;
}
static int
eay_dh_generate_key(DH *dh)
{
int ok = 0;
int generate_new_key = 0;
unsigned l;
BN_CTX *ctx;
#if 0
BN_MONT_CTX *mont = NULL;
#endif
BIGNUM *pub_key = NULL, *priv_key = NULL;
ctx = BN_CTX_new();
if (ctx == NULL) {
goto err;
}
if (dh->priv_key == NULL) {
priv_key = BN_new();
if (priv_key == NULL) {
goto err;
}
generate_new_key = 1;
} else{
priv_key = dh->priv_key;
}
if (dh->pub_key == NULL) {
pub_key = BN_new();
if (pub_key == NULL) {
goto err;
}
} else{
pub_key = dh->pub_key;
}
#if 0
if (dh->flags & DH_FLAG_CACHE_MONT_P) {
mont = BN_MONT_CTX_set_locked(&dh->method_mont_p,
CRYPTO_LOCK_DH, dh->p, ctx);
if (!mont) {
goto err;
}
}
#endif
if (generate_new_key) {
l = dh->length ? dh->length : BN_num_bits(dh->p) - 1; /* secret exponent length */
if (!BN_rand(priv_key, l, 0, 0)) {
goto err;
}
}
{
BIGNUM local_prk;
BIGNUM *prk;
#if 0
if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0) {
BN_init(&local_prk);
prk = &local_prk;
BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
} else
#endif
prk = priv_key;
if (!dh->meth->bn_mod_exp(dh, pub_key, dh->g, prk, dh->p, ctx /* , mont */)) {
goto err;
}
}
dh->pub_key = pub_key;
dh->priv_key = priv_key;
ok = 1;
err:
/*
* if (ok != 1)
* DHerr(DH_F_GENERATE_KEY,ERR_R_BN_LIB);
*/
if ((pub_key != NULL) && (dh->pub_key == NULL)) {
BN_clear_free(pub_key);
}
if ((priv_key != NULL) && (dh->priv_key == NULL)) {
BN_clear_free(priv_key);
}
BN_CTX_free(ctx);
return (ok);
}
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_ossl_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
{
BIGNUM *r1, *m1, *vrfy, *r2, *m[RSA_MAX_PRIME_NUM - 2];
int ret = 0, i, ex_primes = 0, smooth = 0;
RSA_PRIME_INFO *pinfo;
BN_CTX_start(ctx);
r1 = BN_CTX_get(ctx);
r2 = BN_CTX_get(ctx);
m1 = BN_CTX_get(ctx);
vrfy = BN_CTX_get(ctx);
if (vrfy == NULL)
goto err;
if (rsa->version == RSA_ASN1_VERSION_MULTI
&& ((ex_primes = sk_RSA_PRIME_INFO_num(rsa->prime_infos)) <= 0
|| ex_primes > RSA_MAX_PRIME_NUM - 2))
goto err;
if (rsa->flags & RSA_FLAG_CACHE_PRIVATE) {
BIGNUM *factor = BN_new();
if (factor == NULL)
goto err;
/*
* Make sure BN_mod_inverse in Montgomery initialization uses the
* BN_FLG_CONSTTIME flag
*/
if (!(BN_with_flags(factor, rsa->p, BN_FLG_CONSTTIME),
BN_MONT_CTX_set_locked(&rsa->_method_mod_p, rsa->lock,
factor, ctx))
|| !(BN_with_flags(factor, rsa->q, BN_FLG_CONSTTIME),
BN_MONT_CTX_set_locked(&rsa->_method_mod_q, rsa->lock,
factor, ctx))) {
BN_free(factor);
goto err;
}
for (i = 0; i < ex_primes; i++) {
pinfo = sk_RSA_PRIME_INFO_value(rsa->prime_infos, i);
BN_with_flags(factor, pinfo->r, BN_FLG_CONSTTIME);
if (!BN_MONT_CTX_set_locked(&pinfo->m, rsa->lock, factor, ctx)) {
BN_free(factor);
goto err;
}
}
/*
* We MUST free |factor| before any further use of the prime factors
*/
BN_free(factor);
smooth = (ex_primes == 0)
&& (rsa->meth->bn_mod_exp == BN_mod_exp_mont)
&& (BN_num_bits(rsa->q) == BN_num_bits(rsa->p));
}
if (rsa->flags & RSA_FLAG_CACHE_PUBLIC)
if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n, rsa->lock,
rsa->n, ctx))
goto err;
if (smooth) {
/*
* Conversion from Montgomery domain, a.k.a. Montgomery reduction,
* accepts values in [0-m*2^w) range. w is m's bit width rounded up
* to limb width. So that at the very least if |I| is fully reduced,
* i.e. less than p*q, we can count on from-to round to perform
* below modulo operations on |I|. Unlike BN_mod it's constant time.
*/
if (/* m1 = I moq q */
!bn_from_mont_fixed_top(m1, I, rsa->_method_mod_q, ctx)
|| !bn_to_mont_fixed_top(m1, m1, rsa->_method_mod_q, ctx)
/* m1 = m1^dmq1 mod q */
|| !BN_mod_exp_mont_consttime(m1, m1, rsa->dmq1, rsa->q, ctx,
rsa->_method_mod_q)
/* r1 = I mod p */
|| !bn_from_mont_fixed_top(r1, I, rsa->_method_mod_p, ctx)
|| !bn_to_mont_fixed_top(r1, r1, rsa->_method_mod_p, ctx)
/* r1 = r1^dmp1 mod p */
|| !BN_mod_exp_mont_consttime(r1, r1, rsa->dmp1, rsa->p, ctx,
rsa->_method_mod_p)
/* r1 = (r1 - m1) mod p */
/*
* bn_mod_sub_fixed_top is not regular modular subtraction,
* it can tolerate subtrahend to be larger than modulus, but
* not bit-wise wider. This makes up for uncommon q>p case,
* when |m1| can be larger than |rsa->p|.
*/
|| !bn_mod_sub_fixed_top(r1, r1, m1, rsa->p)
/* r1 = r1 * iqmp mod p */
|| !bn_to_mont_fixed_top(r1, r1, rsa->_method_mod_p, ctx)
|| !bn_mul_mont_fixed_top(r1, r1, rsa->iqmp, rsa->_method_mod_p,
ctx)
/* r0 = r1 * q + m1 */
|| !bn_mul_fixed_top(r0, r1, rsa->q, ctx)
|| !bn_mod_add_fixed_top(r0, r0, m1, rsa->n))
goto err;
goto tail;
}
/* compute I mod q */
{
BIGNUM *c = BN_new();
if (c == NULL)
goto err;
BN_with_flags(c, I, BN_FLG_CONSTTIME);
if (!BN_mod(r1, c, rsa->q, ctx)) {
BN_free(c);
goto err;
}
{
BIGNUM *dmq1 = BN_new();
if (dmq1 == NULL) {
BN_free(c);
goto err;
}
BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
/* compute r1^dmq1 mod q */
if (!rsa->meth->bn_mod_exp(m1, r1, dmq1, rsa->q, ctx,
rsa->_method_mod_q)) {
BN_free(c);
BN_free(dmq1);
goto err;
}
/* We MUST free dmq1 before any further use of rsa->dmq1 */
BN_free(dmq1);
}
/* compute I mod p */
if (!BN_mod(r1, c, rsa->p, ctx)) {
BN_free(c);
goto err;
}
/* We MUST free c before any further use of I */
BN_free(c);
}
{
BIGNUM *dmp1 = BN_new();
if (dmp1 == NULL)
goto err;
BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
/* compute r1^dmp1 mod p */
if (!rsa->meth->bn_mod_exp(r0, r1, dmp1, rsa->p, ctx,
rsa->_method_mod_p)) {
BN_free(dmp1);
goto err;
}
/* We MUST free dmp1 before any further use of rsa->dmp1 */
BN_free(dmp1);
}
/*
* calculate m_i in multi-prime case
*
* TODO:
* 1. squash the following two loops and calculate |m_i| there.
* 2. remove cc and reuse |c|.
* 3. remove |dmq1| and |dmp1| in previous block and use |di|.
*
* If these things are done, the code will be more readable.
*/
if (ex_primes > 0) {
BIGNUM *di = BN_new(), *cc = BN_new();
if (cc == NULL || di == NULL) {
BN_free(cc);
BN_free(di);
goto err;
}
for (i = 0; i < ex_primes; i++) {
/* prepare m_i */
if ((m[i] = BN_CTX_get(ctx)) == NULL) {
BN_free(cc);
BN_free(di);
goto err;
}
pinfo = sk_RSA_PRIME_INFO_value(rsa->prime_infos, i);
/* prepare c and d_i */
BN_with_flags(cc, I, BN_FLG_CONSTTIME);
BN_with_flags(di, pinfo->d, BN_FLG_CONSTTIME);
if (!BN_mod(r1, cc, pinfo->r, ctx)) {
BN_free(cc);
BN_free(di);
goto err;
}
/* compute r1 ^ d_i mod r_i */
if (!rsa->meth->bn_mod_exp(m[i], r1, di, pinfo->r, ctx, pinfo->m)) {
BN_free(cc);
BN_free(di);
goto err;
}
}
BN_free(cc);
BN_free(di);
}
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;
{
BIGNUM *pr1 = BN_new();
if (pr1 == NULL)
goto err;
BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
if (!BN_mod(r0, pr1, rsa->p, ctx)) {
BN_free(pr1);
goto err;
}
/* We MUST free pr1 before any further use of r1 */
BN_free(pr1);
}
/*
* 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;
/* add m_i to m in multi-prime case */
if (ex_primes > 0) {
BIGNUM *pr2 = BN_new();
if (pr2 == NULL)
goto err;
for (i = 0; i < ex_primes; i++) {
pinfo = sk_RSA_PRIME_INFO_value(rsa->prime_infos, i);
if (!BN_sub(r1, m[i], r0)) {
BN_free(pr2);
goto err;
}
if (!BN_mul(r2, r1, pinfo->t, ctx)) {
BN_free(pr2);
goto err;
}
BN_with_flags(pr2, r2, BN_FLG_CONSTTIME);
if (!BN_mod(r1, pr2, pinfo->r, ctx)) {
BN_free(pr2);
goto err;
}
if (BN_is_negative(r1))
if (!BN_add(r1, r1, pinfo->r)) {
BN_free(pr2);
goto err;
}
if (!BN_mul(r1, r1, pinfo->pp, ctx)) {
BN_free(pr2);
goto err;
}
if (!BN_add(r0, r0, r1)) {
BN_free(pr2);
goto err;
}
}
BN_free(pr2);
}
tail:
if (rsa->e && rsa->n) {
if (rsa->meth->bn_mod_exp == BN_mod_exp_mont) {
if (!BN_mod_exp_mont(vrfy, r0, rsa->e, rsa->n, ctx,
rsa->_method_mod_n))
goto err;
} else {
bn_correct_top(r0);
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_is_zero(vrfy)) {
bn_correct_top(r0);
ret = 1;
goto err; /* not actually error */
}
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 *d = BN_new();
if (d == NULL)
goto err;
BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
if (!rsa->meth->bn_mod_exp(r0, I, d, rsa->n, ctx,
rsa->_method_mod_n)) {
BN_free(d);
goto err;
}
/* We MUST free d before any further use of rsa->d */
BN_free(d);
}
}
/*
* It's unfortunate that we have to bn_correct_top(r0). What hopefully
* saves the day is that correction is highly unlike, and private key
* operations are customarily performed on blinded message. Which means
* that attacker won't observe correlation with chosen plaintext.
* Secondly, remaining code would still handle it in same computational
* time and even conceal memory access pattern around corrected top.
*/
bn_correct_top(r0);
ret = 1;
err:
BN_CTX_end(ctx);
return ret;
}
static int
RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
{
BIGNUM *r1, *m1, *vrfy;
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);
if (r1 == NULL || m1 == NULL || vrfy == NULL) {
RSAerr(RSA_F_RSA_EAY_MOD_EXP, ERR_R_MALLOC_FAILURE);
goto err;
}
{
BIGNUM p, q;
/*
* Make sure BN_mod_inverse in Montgomery intialization uses the
* BN_FLG_CONSTTIME flag
*/
BN_init(&p);
BN_init(&q);
BN_with_flags(&p, rsa->p, BN_FLG_CONSTTIME);
BN_with_flags(&q, rsa->q, BN_FLG_CONSTTIME);
if (rsa->flags & RSA_FLAG_CACHE_PRIVATE) {
if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_p,
CRYPTO_LOCK_RSA, &p, ctx) ||
!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 */
BN_init(&c);
BN_with_flags(&c, I, BN_FLG_CONSTTIME);
if (!BN_mod(r1, &c, rsa->q, ctx))
goto err;
/* compute r1^dmq1 mod q */
BN_init(&dmq1);
BN_with_flags(&dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
if (!rsa->meth->bn_mod_exp(m1, r1, &dmq1, rsa->q, ctx,
rsa->_method_mod_q))
goto err;
/* compute I mod p */
BN_with_flags(&c, I, BN_FLG_CONSTTIME);
if (!BN_mod(r1, &c, rsa->p, ctx))
goto err;
/* compute r1^dmp1 mod p */
BN_init(&dmp1);
BN_with_flags(&dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
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 */
BN_init(&pr1);
BN_with_flags(&pr1, r1, BN_FLG_CONSTTIME);
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 d;
BN_init(&d);
BN_with_flags(&d, rsa->d, BN_FLG_CONSTTIME);
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_private_decrypt(int flen, const unsigned char *from,
unsigned char *to, RSA *rsa, int padding)
{
BIGNUM *f, *ret, *br;
int j,num=0,r= -1;
unsigned char *p;
unsigned char *buf=NULL;
BN_CTX *ctx=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 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, &br, &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->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_EXP_CONSTTIME))
{
d = &local_d;
BN_with_flags(d, rsa->d, BN_FLG_EXP_CONSTTIME);
}
else
d = rsa->d;
MONT_HELPER(rsa, ctx, 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 (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 */
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);
}
/* BN_mod_inverse_no_branch is a special version of BN_mod_inverse.
* It does not contain branches that may leak sensitive information.
*/
static BIGNUM *BN_mod_inverse_no_branch(BIGNUM *in,
const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx)
{
BIGNUM *A,*B,*X,*Y,*M,*D,*T,*R=NULL;
BIGNUM local_A, local_B;
BIGNUM *pA, *pB;
BIGNUM *ret=NULL;
int sign;
bn_check_top(a);
bn_check_top(n);
BN_CTX_start(ctx);
A = BN_CTX_get(ctx);
B = BN_CTX_get(ctx);
X = BN_CTX_get(ctx);
D = BN_CTX_get(ctx);
M = BN_CTX_get(ctx);
Y = BN_CTX_get(ctx);
T = BN_CTX_get(ctx);
if (T == NULL) goto err;
if (in == NULL)
R=BN_new();
else
R=in;
if (R == NULL) goto err;
BN_one(X);
BN_zero(Y);
if (BN_copy(B,a) == NULL) goto err;
if (BN_copy(A,n) == NULL) goto err;
A->neg = 0;
if (B->neg || (BN_ucmp(B, A) >= 0))
{
/* Turn BN_FLG_CONSTTIME flag on, so that when BN_div is invoked,
* BN_div_no_branch will be called eventually.
*/
pB = &local_B;
BN_with_flags(pB, B, BN_FLG_CONSTTIME);
if (!BN_nnmod(B, pB, A, ctx)) goto err;
}
sign = -1;
/* From B = a mod |n|, A = |n| it follows that
*
* 0 <= B < A,
* -sign*X*a == B (mod |n|),
* sign*Y*a == A (mod |n|).
*/
while (!BN_is_zero(B))
{
BIGNUM *tmp;
/*
* 0 < B < A,
* (*) -sign*X*a == B (mod |n|),
* sign*Y*a == A (mod |n|)
*/
/* Turn BN_FLG_CONSTTIME flag on, so that when BN_div is invoked,
* BN_div_no_branch will be called eventually.
*/
pA = &local_A;
BN_with_flags(pA, A, BN_FLG_CONSTTIME);
/* (D, M) := (A/B, A%B) ... */
if (!BN_div(D,M,pA,B,ctx)) goto err;
/* Now
* A = D*B + M;
* thus we have
* (**) sign*Y*a == D*B + M (mod |n|).
*/
tmp=A; /* keep the BIGNUM object, the value does not matter */
/* (A, B) := (B, A mod B) ... */
A=B;
B=M;
/* ... so we have 0 <= B < A again */
/* Since the former M is now B and the former B is now A,
* (**) translates into
* sign*Y*a == D*A + B (mod |n|),
* i.e.
* sign*Y*a - D*A == B (mod |n|).
* Similarly, (*) translates into
* -sign*X*a == A (mod |n|).
*
* Thus,
* sign*Y*a + D*sign*X*a == B (mod |n|),
* i.e.
* sign*(Y + D*X)*a == B (mod |n|).
*
* So if we set (X, Y, sign) := (Y + D*X, X, -sign), we arrive back at
* -sign*X*a == B (mod |n|),
* sign*Y*a == A (mod |n|).
* Note that X and Y stay non-negative all the time.
*/
if (!BN_mul(tmp,D,X,ctx)) goto err;
if (!BN_add(tmp,tmp,Y)) goto err;
M=Y; /* keep the BIGNUM object, the value does not matter */
Y=X;
X=tmp;
sign = -sign;
}
/*
* The while loop (Euclid's algorithm) ends when
* A == gcd(a,n);
* we have
* sign*Y*a == A (mod |n|),
* where Y is non-negative.
*/
if (sign < 0)
{
if (!BN_sub(Y,n,Y)) goto err;
}
/* Now Y*a == A (mod |n|). */
if (BN_is_one(A))
{
/* Y*a == 1 (mod |n|) */
if (!Y->neg && BN_ucmp(Y,n) < 0)
{
if (!BN_copy(R,Y)) goto err;
}
else
{
if (!BN_nnmod(R,Y,n,ctx)) goto err;
}
}
else
{
BNerr(BN_F_BN_MOD_INVERSE_NO_BRANCH,BN_R_NO_INVERSE);
goto err;
}
ret=R;
err:
if ((ret == NULL) && (in == NULL)) BN_free(R);
BN_CTX_end(ctx);
bn_check_top(ret);
return(ret);
}
int rsa_default_multi_prime_keygen(RSA *rsa, int bits, int num_primes,
BIGNUM *e_value, BN_GENCB *cb) {
BIGNUM *r0 = NULL, *r1 = NULL, *r2 = NULL, *r3 = NULL, *tmp;
BIGNUM local_r0, local_d, local_p;
BIGNUM *pr0, *d, *p;
int prime_bits, ok = -1, n = 0, i, j;
BN_CTX *ctx = NULL;
STACK_OF(RSA_additional_prime) *additional_primes = NULL;
if (num_primes < 2) {
ok = 0; /* we set our own err */
OPENSSL_PUT_ERROR(RSA, RSA_R_MUST_HAVE_AT_LEAST_TWO_PRIMES);
goto err;
}
ctx = BN_CTX_new();
if (ctx == NULL) {
goto err;
}
BN_CTX_start(ctx);
r0 = BN_CTX_get(ctx);
r1 = BN_CTX_get(ctx);
r2 = BN_CTX_get(ctx);
r3 = BN_CTX_get(ctx);
if (r0 == NULL || r1 == NULL || r2 == NULL || r3 == NULL) {
goto err;
}
if (num_primes > 2) {
additional_primes = sk_RSA_additional_prime_new_null();
if (additional_primes == NULL) {
goto err;
}
}
for (i = 2; i < num_primes; i++) {
RSA_additional_prime *ap = OPENSSL_malloc(sizeof(RSA_additional_prime));
if (ap == NULL) {
goto err;
}
memset(ap, 0, sizeof(RSA_additional_prime));
ap->prime = BN_new();
ap->exp = BN_new();
ap->coeff = BN_new();
ap->r = BN_new();
if (ap->prime == NULL ||
ap->exp == NULL ||
ap->coeff == NULL ||
ap->r == NULL ||
!sk_RSA_additional_prime_push(additional_primes, ap)) {
RSA_additional_prime_free(ap);
goto err;
}
}
/* We need the RSA components non-NULL */
if (!rsa->n && ((rsa->n = BN_new()) == NULL)) {
goto err;
}
if (!rsa->d && ((rsa->d = BN_new()) == NULL)) {
goto err;
}
if (!rsa->e && ((rsa->e = BN_new()) == NULL)) {
goto err;
}
if (!rsa->p && ((rsa->p = BN_new()) == NULL)) {
goto err;
}
if (!rsa->q && ((rsa->q = BN_new()) == NULL)) {
goto err;
}
if (!rsa->dmp1 && ((rsa->dmp1 = BN_new()) == NULL)) {
goto err;
}
if (!rsa->dmq1 && ((rsa->dmq1 = BN_new()) == NULL)) {
goto err;
}
if (!rsa->iqmp && ((rsa->iqmp = BN_new()) == NULL)) {
goto err;
}
if (!BN_copy(rsa->e, e_value)) {
goto err;
}
/* generate p and q */
prime_bits = (bits + (num_primes - 1)) / num_primes;
for (;;) {
if (!BN_generate_prime_ex(rsa->p, prime_bits, 0, NULL, NULL, cb) ||
!BN_sub(r2, rsa->p, BN_value_one()) ||
!BN_gcd(r1, r2, rsa->e, ctx)) {
goto err;
}
if (BN_is_one(r1)) {
break;
}
if (!BN_GENCB_call(cb, 2, n++)) {
goto err;
}
}
if (!BN_GENCB_call(cb, 3, 0)) {
goto err;
}
prime_bits = ((bits - prime_bits) + (num_primes - 2)) / (num_primes - 1);
for (;;) {
/* When generating ridiculously small keys, we can get stuck
* continually regenerating the same prime values. Check for
* this and bail if it happens 3 times. */
unsigned int degenerate = 0;
do {
if (!BN_generate_prime_ex(rsa->q, prime_bits, 0, NULL, NULL, cb)) {
goto err;
}
} while ((BN_cmp(rsa->p, rsa->q) == 0) && (++degenerate < 3));
if (degenerate == 3) {
ok = 0; /* we set our own err */
OPENSSL_PUT_ERROR(RSA, RSA_R_KEY_SIZE_TOO_SMALL);
goto err;
}
if (!BN_sub(r2, rsa->q, BN_value_one()) ||
!BN_gcd(r1, r2, rsa->e, ctx)) {
goto err;
}
if (BN_is_one(r1)) {
break;
}
if (!BN_GENCB_call(cb, 2, n++)) {
goto err;
}
}
if (!BN_GENCB_call(cb, 3, 1) ||
!BN_mul(rsa->n, rsa->p, rsa->q, ctx)) {
goto err;
}
for (i = 2; i < num_primes; i++) {
RSA_additional_prime *ap =
sk_RSA_additional_prime_value(additional_primes, i - 2);
prime_bits = ((bits - BN_num_bits(rsa->n)) + (num_primes - (i + 1))) /
(num_primes - i);
for (;;) {
if (!BN_generate_prime_ex(ap->prime, prime_bits, 0, NULL, NULL, cb)) {
goto err;
}
if (BN_cmp(rsa->p, ap->prime) == 0 ||
BN_cmp(rsa->q, ap->prime) == 0) {
continue;
}
for (j = 0; j < i - 2; j++) {
if (BN_cmp(sk_RSA_additional_prime_value(additional_primes, j)->prime,
ap->prime) == 0) {
break;
}
}
if (j != i - 2) {
continue;
}
if (!BN_sub(r2, ap->prime, BN_value_one()) ||
!BN_gcd(r1, r2, rsa->e, ctx)) {
goto err;
}
if (!BN_is_one(r1)) {
continue;
}
if (i != num_primes - 1) {
break;
}
/* For the last prime we'll check that it makes n large enough. In the
* two prime case this isn't a problem because we generate primes with
* the top two bits set and so the product is always of the expected
* size. In the multi prime case, this doesn't follow. */
if (!BN_mul(r1, rsa->n, ap->prime, ctx)) {
goto err;
}
if (BN_num_bits(r1) == (unsigned) bits) {
break;
}
if (!BN_GENCB_call(cb, 2, n++)) {
goto err;
}
}
/* ap->r is is the product of all the primes prior to the current one
* (including p and q). */
if (!BN_copy(ap->r, rsa->n)) {
goto err;
}
if (i == num_primes - 1) {
/* In the case of the last prime, we calculated n as |r1| in the loop
* above. */
if (!BN_copy(rsa->n, r1)) {
goto err;
}
} else if (!BN_mul(rsa->n, rsa->n, ap->prime, ctx)) {
goto err;
}
if (!BN_GENCB_call(cb, 3, 1)) {
goto err;
}
}
if (BN_cmp(rsa->p, rsa->q) < 0) {
tmp = rsa->p;
rsa->p = rsa->q;
rsa->q = tmp;
}
/* calculate d */
if (!BN_sub(r1, rsa->p, BN_value_one())) {
goto err; /* p-1 */
}
if (!BN_sub(r2, rsa->q, BN_value_one())) {
goto err; /* q-1 */
}
if (!BN_mul(r0, r1, r2, ctx)) {
goto err; /* (p-1)(q-1) */
}
for (i = 2; i < num_primes; i++) {
RSA_additional_prime *ap =
sk_RSA_additional_prime_value(additional_primes, i - 2);
if (!BN_sub(r3, ap->prime, BN_value_one()) ||
!BN_mul(r0, r0, r3, ctx)) {
goto err;
}
}
pr0 = &local_r0;
BN_with_flags(pr0, r0, BN_FLG_CONSTTIME);
if (!BN_mod_inverse(rsa->d, rsa->e, pr0, ctx)) {
goto err; /* d */
}
/* set up d for correct BN_FLG_CONSTTIME flag */
d = &local_d;
BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
/* calculate d mod (p-1) */
if (!BN_mod(rsa->dmp1, d, r1, ctx)) {
goto err;
}
/* calculate d mod (q-1) */
if (!BN_mod(rsa->dmq1, d, r2, ctx)) {
goto err;
}
/* calculate inverse of q mod p */
p = &local_p;
BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);
if (!BN_mod_inverse(rsa->iqmp, rsa->q, p, ctx)) {
goto err;
}
for (i = 2; i < num_primes; i++) {
RSA_additional_prime *ap =
sk_RSA_additional_prime_value(additional_primes, i - 2);
if (!BN_sub(ap->exp, ap->prime, BN_value_one()) ||
!BN_mod(ap->exp, rsa->d, ap->exp, ctx) ||
!BN_mod_inverse(ap->coeff, ap->r, ap->prime, ctx)) {
goto err;
}
}
ok = 1;
rsa->additional_primes = additional_primes;
additional_primes = NULL;
err:
if (ok == -1) {
OPENSSL_PUT_ERROR(RSA, ERR_LIB_BN);
ok = 0;
}
if (ctx != NULL) {
BN_CTX_end(ctx);
BN_CTX_free(ctx);
}
sk_RSA_additional_prime_pop_free(additional_primes,
RSA_additional_prime_free);
return ok;
}
static int rsa_builtin_keygen(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb)
{
BIGNUM *r0=NULL,*r1=NULL,*r2=NULL,*r3=NULL,*tmp;
BIGNUM local_r0,local_d,local_p;
BIGNUM *pr0,*d,*p;
int bitsp,bitsq,ok= -1,n=0;
BN_CTX *ctx=NULL;
ctx=BN_CTX_new();
if (ctx == NULL) goto err;
BN_CTX_start(ctx);
r0 = BN_CTX_get(ctx);
r1 = BN_CTX_get(ctx);
r2 = BN_CTX_get(ctx);
r3 = BN_CTX_get(ctx);
if (r3 == NULL) goto err;
bitsp=(bits+1)/2;
bitsq=bits-bitsp;
/* We need the RSA components non-NULL */
if(!rsa->n && ((rsa->n=BN_new()) == NULL)) goto err;
if(!rsa->d && ((rsa->d=BN_new()) == NULL)) goto err;
if(!rsa->e && ((rsa->e=BN_new()) == NULL)) goto err;
if(!rsa->p && ((rsa->p=BN_new()) == NULL)) goto err;
if(!rsa->q && ((rsa->q=BN_new()) == NULL)) goto err;
if(!rsa->dmp1 && ((rsa->dmp1=BN_new()) == NULL)) goto err;
if(!rsa->dmq1 && ((rsa->dmq1=BN_new()) == NULL)) goto err;
if(!rsa->iqmp && ((rsa->iqmp=BN_new()) == NULL)) goto err;
BN_copy(rsa->e, e_value);
/* generate p and q */
for (;;)
{
if(!BN_generate_prime_ex(rsa->p, bitsp, 0, NULL, NULL, cb))
goto err;
if (!BN_sub(r2,rsa->p,BN_value_one())) goto err;
if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
if (BN_is_one(r1)) break;
if(!BN_GENCB_call(cb, 2, n++))
goto err;
}
if(!BN_GENCB_call(cb, 3, 0))
goto err;
for (;;)
{
/* When generating ridiculously small keys, we can get stuck
* continually regenerating the same prime values. Check for
* this and bail if it happens 3 times. */
unsigned int degenerate = 0;
do
{
if(!BN_generate_prime_ex(rsa->q, bitsq, 0, NULL, NULL, cb))
goto err;
} while((BN_cmp(rsa->p, rsa->q) == 0) && (++degenerate < 3));
if(degenerate == 3)
{
ok = 0; /* we set our own err */
RSAerr(RSA_F_RSA_BUILTIN_KEYGEN,RSA_R_KEY_SIZE_TOO_SMALL);
goto err;
}
if (!BN_sub(r2,rsa->q,BN_value_one())) goto err;
if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
if (BN_is_one(r1))
break;
if(!BN_GENCB_call(cb, 2, n++))
goto err;
}
if(!BN_GENCB_call(cb, 3, 1))
goto err;
if (BN_cmp(rsa->p,rsa->q) < 0)
{
tmp=rsa->p;
rsa->p=rsa->q;
rsa->q=tmp;
}
/* calculate n */
if (!BN_mul(rsa->n,rsa->p,rsa->q,ctx)) goto err;
/* calculate d */
if (!BN_sub(r1,rsa->p,BN_value_one())) goto err; /* p-1 */
if (!BN_sub(r2,rsa->q,BN_value_one())) goto err; /* q-1 */
if (!BN_mul(r0,r1,r2,ctx)) goto err; /* (p-1)(q-1) */
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
{
pr0 = &local_r0;
BN_with_flags(pr0, r0, BN_FLG_CONSTTIME);
}
else
pr0 = r0;
if (!BN_mod_inverse(rsa->d,rsa->e,pr0,ctx)) goto err; /* d */
/* set up d for correct BN_FLG_CONSTTIME flag */
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
{
d = &local_d;
BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
}
else
d = rsa->d;
/* calculate d mod (p-1) */
if (!BN_mod(rsa->dmp1,d,r1,ctx)) goto err;
/* calculate d mod (q-1) */
if (!BN_mod(rsa->dmq1,d,r2,ctx)) goto err;
/* calculate inverse of q mod p */
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
{
p = &local_p;
BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);
}
else
p = rsa->p;
if (!BN_mod_inverse(rsa->iqmp,rsa->q,p,ctx)) goto err;
ok=1;
err:
if (ok == -1)
{
RSAerr(RSA_F_RSA_BUILTIN_KEYGEN,ERR_LIB_BN);
ok=0;
}
if (ctx != NULL)
{
BN_CTX_end(ctx);
BN_CTX_free(ctx);
}
return ok;
}
static int rsa_ossl_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
{
BIGNUM *r1, *m1, *vrfy, *r2, *m[RSA_MAX_PRIME_NUM - 2];
int ret = 0, i, ex_primes = 0;
RSA_PRIME_INFO *pinfo;
BN_CTX_start(ctx);
r1 = BN_CTX_get(ctx);
r2 = BN_CTX_get(ctx);
m1 = BN_CTX_get(ctx);
vrfy = BN_CTX_get(ctx);
if (vrfy == NULL)
goto err;
if (rsa->version == RSA_ASN1_VERSION_MULTI
&& ((ex_primes = sk_RSA_PRIME_INFO_num(rsa->prime_infos)) <= 0
|| ex_primes > RSA_MAX_PRIME_NUM - 2))
goto err;
{
BIGNUM *p = BN_new(), *q = BN_new();
/*
* Make sure BN_mod_inverse in Montgomery initialization uses the
* BN_FLG_CONSTTIME flag
*/
if (p == NULL || q == NULL) {
BN_free(p);
BN_free(q);
goto err;
}
BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);
BN_with_flags(q, rsa->q, BN_FLG_CONSTTIME);
if (rsa->flags & RSA_FLAG_CACHE_PRIVATE) {
if (!BN_MONT_CTX_set_locked
(&rsa->_method_mod_p, rsa->lock, p, ctx)
|| !BN_MONT_CTX_set_locked(&rsa->_method_mod_q,
rsa->lock, q, ctx)) {
BN_free(p);
BN_free(q);
goto err;
}
if (ex_primes > 0) {
/* cache BN_MONT_CTX for other primes */
BIGNUM *r = BN_new();
if (r == NULL) {
BN_free(p);
BN_free(q);
goto err;
}
for (i = 0; i < ex_primes; i++) {
pinfo = sk_RSA_PRIME_INFO_value(rsa->prime_infos, i);
BN_with_flags(r, pinfo->r, BN_FLG_CONSTTIME);
if (!BN_MONT_CTX_set_locked(&pinfo->m, rsa->lock, r, ctx)) {
BN_free(p);
BN_free(q);
BN_free(r);
goto err;
}
}
BN_free(r);
}
}
/*
* We MUST free p and q before any further use of rsa->p and rsa->q
*/
BN_free(p);
BN_free(q);
}
if (rsa->flags & RSA_FLAG_CACHE_PUBLIC)
if (!BN_MONT_CTX_set_locked
(&rsa->_method_mod_n, rsa->lock, rsa->n, ctx))
goto err;
/* compute I mod q */
{
BIGNUM *c = BN_new();
if (c == NULL)
goto err;
BN_with_flags(c, I, BN_FLG_CONSTTIME);
if (!BN_mod(r1, c, rsa->q, ctx)) {
BN_free(c);
goto err;
}
{
BIGNUM *dmq1 = BN_new();
if (dmq1 == NULL) {
BN_free(c);
goto err;
}
BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
/* compute r1^dmq1 mod q */
if (!rsa->meth->bn_mod_exp(m1, r1, dmq1, rsa->q, ctx,
rsa->_method_mod_q)) {
BN_free(c);
BN_free(dmq1);
goto err;
}
/* We MUST free dmq1 before any further use of rsa->dmq1 */
BN_free(dmq1);
}
/* compute I mod p */
if (!BN_mod(r1, c, rsa->p, ctx)) {
BN_free(c);
goto err;
}
/* We MUST free c before any further use of I */
BN_free(c);
}
{
BIGNUM *dmp1 = BN_new();
if (dmp1 == NULL)
goto err;
BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
/* compute r1^dmp1 mod p */
if (!rsa->meth->bn_mod_exp(r0, r1, dmp1, rsa->p, ctx,
rsa->_method_mod_p)) {
BN_free(dmp1);
goto err;
}
/* We MUST free dmp1 before any further use of rsa->dmp1 */
BN_free(dmp1);
}
/*
* calculate m_i in multi-prime case
*
* TODO:
* 1. squash the following two loops and calculate |m_i| there.
* 2. remove cc and reuse |c|.
* 3. remove |dmq1| and |dmp1| in previous block and use |di|.
*
* If these things are done, the code will be more readable.
*/
if (ex_primes > 0) {
BIGNUM *di = BN_new(), *cc = BN_new();
if (cc == NULL || di == NULL) {
BN_free(cc);
BN_free(di);
goto err;
}
for (i = 0; i < ex_primes; i++) {
/* prepare m_i */
if ((m[i] = BN_CTX_get(ctx)) == NULL) {
BN_free(cc);
BN_free(di);
goto err;
}
pinfo = sk_RSA_PRIME_INFO_value(rsa->prime_infos, i);
/* prepare c and d_i */
BN_with_flags(cc, I, BN_FLG_CONSTTIME);
BN_with_flags(di, pinfo->d, BN_FLG_CONSTTIME);
if (!BN_mod(r1, cc, pinfo->r, ctx)) {
BN_free(cc);
BN_free(di);
goto err;
}
/* compute r1 ^ d_i mod r_i */
if (!rsa->meth->bn_mod_exp(m[i], r1, di, pinfo->r, ctx, pinfo->m)) {
BN_free(cc);
BN_free(di);
goto err;
}
}
BN_free(cc);
BN_free(di);
}
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;
{
BIGNUM *pr1 = BN_new();
if (pr1 == NULL)
goto err;
BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
if (!BN_mod(r0, pr1, rsa->p, ctx)) {
BN_free(pr1);
goto err;
}
/* We MUST free pr1 before any further use of r1 */
BN_free(pr1);
}
/*
* 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;
/* add m_i to m in multi-prime case */
if (ex_primes > 0) {
BIGNUM *pr2 = BN_new();
if (pr2 == NULL)
goto err;
for (i = 0; i < ex_primes; i++) {
pinfo = sk_RSA_PRIME_INFO_value(rsa->prime_infos, i);
if (!BN_sub(r1, m[i], r0)) {
BN_free(pr2);
goto err;
}
if (!BN_mul(r2, r1, pinfo->t, ctx)) {
BN_free(pr2);
goto err;
}
BN_with_flags(pr2, r2, BN_FLG_CONSTTIME);
if (!BN_mod(r1, pr2, pinfo->r, ctx)) {
BN_free(pr2);
goto err;
}
if (BN_is_negative(r1))
if (!BN_add(r1, r1, pinfo->r)) {
BN_free(pr2);
goto err;
}
if (!BN_mul(r1, r1, pinfo->pp, ctx)) {
BN_free(pr2);
goto err;
}
if (!BN_add(r0, r0, r1)) {
BN_free(pr2);
goto err;
}
}
BN_free(pr2);
}
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 *d = BN_new();
if (d == NULL)
goto err;
BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
if (!rsa->meth->bn_mod_exp(r0, I, d, rsa->n, ctx,
rsa->_method_mod_n)) {
BN_free(d);
goto err;
}
/* We MUST free d before any further use of rsa->d */
BN_free(d);
}
}
ret = 1;
err:
BN_CTX_end(ctx);
return ret;
}
static int rsa_ossl_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 (ret == NULL || buf == NULL) {
RSAerr(RSA_F_RSA_OSSL_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_OSSL_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_OSSL_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_OSSL_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
goto err;
}
}
if (blinding != NULL) {
if (!local_blinding && ((unblind = BN_CTX_get(ctx)) == NULL)) {
RSAerr(RSA_F_RSA_OSSL_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->version == RSA_ASN1_VERSION_MULTI) ||
((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 *d = BN_new();
if (d == NULL) {
RSAerr(RSA_F_RSA_OSSL_PRIVATE_DECRYPT, ERR_R_MALLOC_FAILURE);
goto err;
}
BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
if (rsa->flags & RSA_FLAG_CACHE_PUBLIC)
if (!BN_MONT_CTX_set_locked
(&rsa->_method_mod_n, rsa->lock, rsa->n, ctx)) {
BN_free(d);
goto err;
}
if (!rsa->meth->bn_mod_exp(ret, f, d, rsa->n, ctx,
rsa->_method_mod_n)) {
BN_free(d);
goto err;
}
/* We MUST free d before any further use of rsa->d */
BN_free(d);
}
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;
case RSA_PKCS1_OAEP_PADDING:
r = RSA_padding_check_PKCS1_OAEP(to, num, buf, j, num, NULL, 0);
break;
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_OSSL_PRIVATE_DECRYPT, RSA_R_UNKNOWN_PADDING_TYPE);
goto err;
}
if (r < 0)
RSAerr(RSA_F_RSA_OSSL_PRIVATE_DECRYPT, RSA_R_PADDING_CHECK_FAILED);
err:
if (ctx != NULL)
BN_CTX_end(ctx);
BN_CTX_free(ctx);
OPENSSL_clear_free(buf, num);
return r;
}
/* signing */
static int rsa_ossl_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 (ret == NULL || buf == NULL) {
RSAerr(RSA_F_RSA_OSSL_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_OSSL_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_OSSL_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_OSSL_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR);
goto err;
}
}
if (blinding != NULL) {
if (!local_blinding && ((unblind = BN_CTX_get(ctx)) == NULL)) {
RSAerr(RSA_F_RSA_OSSL_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->version == RSA_ASN1_VERSION_MULTI) ||
((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 *d = BN_new();
if (d == NULL) {
RSAerr(RSA_F_RSA_OSSL_PRIVATE_ENCRYPT, ERR_R_MALLOC_FAILURE);
goto err;
}
BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
if (rsa->flags & RSA_FLAG_CACHE_PUBLIC)
if (!BN_MONT_CTX_set_locked
(&rsa->_method_mod_n, rsa->lock, rsa->n, ctx)) {
BN_free(d);
goto err;
}
if (!rsa->meth->bn_mod_exp(ret, f, d, rsa->n, ctx,
rsa->_method_mod_n)) {
BN_free(d);
goto err;
}
/* We MUST free d before any further use of rsa->d */
BN_free(d);
}
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);
OPENSSL_clear_free(buf, num);
return r;
}
static int rsa_ossl_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
{
BIGNUM *r1, *m1, *vrfy;
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 = NULL, *local_q = NULL;
BIGNUM *p = NULL, *q = NULL;
/*
* Make sure BN_mod_inverse in Montgomery initialization uses the
* BN_FLG_CONSTTIME flag (unless RSA_FLAG_NO_CONSTTIME is set)
*/
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
local_p = p = BN_new();
if (p == NULL)
goto err;
BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);
local_q = q = BN_new();
if (q == NULL) {
BN_free(local_p);
goto err;
}
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)
|| !BN_MONT_CTX_set_locked(&rsa->_method_mod_q,
CRYPTO_LOCK_RSA, q, ctx)) {
BN_free(local_p);
BN_free(local_q);
goto err;
}
}
/*
* We MUST free local_p and local_q before any further use of rsa->p and
* rsa->q
*/
BN_free(local_p);
BN_free(local_q);
}
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 */
{
BIGNUM *local_c = NULL;
const BIGNUM *c;
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
local_c = BN_new();
if (local_c == NULL)
goto err;
BN_with_flags(local_c, I, BN_FLG_CONSTTIME);
c = local_c;
} else {
c = I;
}
if (!BN_mod(r1, c, rsa->q, ctx)) {
BN_free(local_c);
goto err;
}
{
BIGNUM *local_dmq1 = NULL, *dmq1;
/* compute r1^dmq1 mod q */
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
dmq1 = local_dmq1 = BN_new();
if (local_dmq1 == NULL) {
BN_free(local_c);
goto err;
}
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)) {
BN_free(local_c);
BN_free(local_dmq1);
goto err;
}
/* We MUST free local_dmq1 before any further use of rsa->dmq1 */
BN_free(local_dmq1);
}
/* compute I mod p */
if (!BN_mod(r1, c, rsa->p, ctx)) {
BN_free(local_c);
goto err;
}
/* We MUST free local_c before any further use of I */
BN_free(local_c);
}
{
BIGNUM *local_dmp1 = NULL, *dmp1;
/* compute r1^dmp1 mod p */
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
dmp1 = local_dmp1 = BN_new();
if (local_dmp1 == NULL)
goto err;
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)) {
BN_free(local_dmp1);
goto err;
}
/* We MUST free local_dmp1 before any further use of rsa->dmp1 */
BN_free(local_dmp1);
}
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;
{
BIGNUM *local_r1 = NULL, *pr1;
/* Turn BN_FLG_CONSTTIME flag on before division operation */
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
pr1 = local_r1 = BN_new();
if (local_r1 == NULL)
goto err;
BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
} else {
pr1 = r1;
}
if (!BN_mod(r0, pr1, rsa->p, ctx)) {
BN_free(local_r1);
goto err;
}
/* We MUST free local_r1 before any further use of r1 */
BN_free(local_r1);
}
/*
* 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 = NULL;
BIGNUM *d = NULL;
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
local_d = d = BN_new();
if (d == NULL)
goto err;
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)) {
BN_free(local_d);
goto err;
}
/* We MUST free local_d before any further use of rsa->d */
BN_free(local_d);
}
}
ret = 1;
err:
BN_CTX_end(ctx);
return (ret);
}
static int dsa_builtin_keygen(DSA *dsa)
{
int ok = 0;
BN_CTX *ctx = NULL;
BIGNUM *pub_key = NULL, *priv_key = NULL;
if (FIPS_mode()
&& (BN_num_bits(dsa->p) < OPENSSL_DSA_FIPS_MIN_MODULUS_BITS)) {
DSAerr(DSA_F_DSA_BUILTIN_KEYGEN, DSA_R_KEY_SIZE_TOO_SMALL);
goto err;
}
if ((ctx = BN_CTX_new()) == NULL)
goto err;
if (dsa->priv_key == NULL) {
if ((priv_key = BN_new()) == NULL)
goto err;
} else
priv_key = dsa->priv_key;
do
if (!BN_rand_range(priv_key, dsa->q))
goto err;
while (BN_is_zero(priv_key)) ;
if (dsa->pub_key == NULL) {
if ((pub_key = BN_new()) == NULL)
goto err;
} else
pub_key = dsa->pub_key;
{
BIGNUM local_prk;
BIGNUM *prk;
if ((dsa->flags & DSA_FLAG_NO_EXP_CONSTTIME) == 0) {
BN_init(&local_prk);
prk = &local_prk;
BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
} else
prk = priv_key;
if (!BN_mod_exp(pub_key, dsa->g, prk, dsa->p, ctx))
goto err;
}
dsa->priv_key = priv_key;
dsa->pub_key = pub_key;
if (fips_dsa_pairwise_fail)
BN_add_word(dsa->pub_key, 1);
if (!fips_check_dsa(dsa))
goto err;
ok = 1;
err:
if ((pub_key != NULL) && (dsa->pub_key == NULL))
BN_free(pub_key);
if ((priv_key != NULL) && (dsa->priv_key == NULL))
BN_free(priv_key);
if (ctx != NULL)
BN_CTX_free(ctx);
return (ok);
}
static int generate_key(DH *dh)
{
int ok = 0;
int generate_new_key = 0;
unsigned l;
BN_CTX *ctx;
BN_MONT_CTX *mont = NULL;
BIGNUM *pub_key = NULL, *priv_key = NULL;
ctx = BN_CTX_new();
if (ctx == NULL)
goto err;
if (dh->priv_key == NULL) {
priv_key = BN_new();
if (priv_key == NULL)
goto err;
generate_new_key = 1;
} else
priv_key = dh->priv_key;
if (dh->pub_key == NULL) {
pub_key = BN_new();
if (pub_key == NULL)
goto err;
} else
pub_key = dh->pub_key;
if (dh->flags & DH_FLAG_CACHE_MONT_P) {
mont = BN_MONT_CTX_set_locked(&dh->method_mont_p,
CRYPTO_LOCK_DH, dh->p, ctx);
if (!mont)
goto err;
}
if (generate_new_key) {
if (dh->q) {
do {
if (!BN_rand_range(priv_key, dh->q))
goto err;
}
while (BN_is_zero(priv_key) || BN_is_one(priv_key));
} else {
/* secret exponent length */
l = dh->length ? dh->length : BN_num_bits(dh->p) - 1;
if (!BN_rand(priv_key, l, 0, 0))
goto err;
}
}
{
BIGNUM local_prk;
BIGNUM *prk;
if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0) {
BN_init(&local_prk);
prk = &local_prk;
BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
} else
prk = priv_key;
if (!dh->meth->bn_mod_exp(dh, pub_key, dh->g, prk, dh->p, ctx, mont))
goto err;
}
dh->pub_key = pub_key;
dh->priv_key = priv_key;
ok = 1;
err:
if (ok != 1)
DHerr(DH_F_GENERATE_KEY, ERR_R_BN_LIB);
if ((pub_key != NULL) && (dh->pub_key == NULL))
BN_free(pub_key);
if ((priv_key != NULL) && (dh->priv_key == NULL))
BN_free(priv_key);
BN_CTX_free(ctx);
return (ok);
}
static int rsa_builtin_multi_prime_keygen(RSA *rsa, int bits, int num_primes, BIGNUM *e_value, BN_GENCB *cb)
{
BIGNUM *r0=NULL,*r1=NULL,*r2=NULL,*r3=NULL,*tmp;
BIGNUM local_r0,local_d,local_p;
BIGNUM *pr0,*d,*p;
int prime_bits, ok= -1,n=0,i,j;
BN_CTX *ctx=NULL;
#ifdef OPENSSL_CRYPTOCOP
static int cryptocop_count;
#endif
STACK_OF(RSA_additional_prime) *additional_primes = NULL;
if (num_primes < 2)
{
ok = 0; /* we set our own err */
RSAerr(RSA_F_RSA_BUILTIN_KEYGEN, RSA_R_MUST_HAVE_AT_LEAST_TWO_PRIMES);
goto err;
}
ctx=BN_CTX_new();
if (ctx == NULL) goto err;
BN_CTX_start(ctx);
r0 = BN_CTX_get(ctx);
r1 = BN_CTX_get(ctx);
r2 = BN_CTX_get(ctx);
r3 = BN_CTX_get(ctx);
if (r3 == NULL) goto err;
if (num_primes > 2)
{
if ((additional_primes = sk_RSA_additional_prime_new_null()) == NULL)
goto err;
}
#ifdef OPENSSL_CRYPTOCOP
if(bits < CRYPTOCOP_MIN_RSA_BITS && cryptocop_count < CRYPTOCOP_COUNT_MAX) {
syslog(LOG_ERR, "RSA key generation with %d bits " CRYPTOCOP_INFO, bits);
cryptocop_count++;
}
#endif
for (i = 2; i < num_primes; i++)
{
RSA_additional_prime *ap = OPENSSL_malloc(sizeof(RSA_additional_prime));
if (ap == NULL)
goto err;
memset(ap, 0, sizeof(RSA_additional_prime));
if ((ap->prime = BN_new()) == NULL)
goto err;
if ((ap->exp = BN_new()) == NULL)
goto err;
if ((ap->coeff = BN_new()) == NULL)
goto err;
if ((ap->r = BN_new()) == NULL)
goto err;
if (!sk_RSA_additional_prime_push(additional_primes, ap))
goto err;
}
/* We need the RSA components non-NULL */
if(!rsa->n && ((rsa->n=BN_new()) == NULL)) goto err;
if(!rsa->d && ((rsa->d=BN_new()) == NULL)) goto err;
if(!rsa->e && ((rsa->e=BN_new()) == NULL)) goto err;
if(!rsa->p && ((rsa->p=BN_new()) == NULL)) goto err;
if(!rsa->q && ((rsa->q=BN_new()) == NULL)) goto err;
if(!rsa->dmp1 && ((rsa->dmp1=BN_new()) == NULL)) goto err;
if(!rsa->dmq1 && ((rsa->dmq1=BN_new()) == NULL)) goto err;
if(!rsa->iqmp && ((rsa->iqmp=BN_new()) == NULL)) goto err;
BN_copy(rsa->e, e_value);
/* generate p and q. */
prime_bits = (bits+(num_primes-1))/num_primes;
for (;;)
{
if(!BN_generate_prime_ex(rsa->p, prime_bits, 0, NULL, NULL, cb))
goto err;
if (!BN_sub(r2,rsa->p,BN_value_one())) goto err;
if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
if (BN_is_one(r1)) break;
if(!BN_GENCB_call(cb, 2, n++))
goto err;
}
if(!BN_GENCB_call(cb, 3, 0))
goto err;
prime_bits = ((bits-prime_bits) + (num_primes-2))/(num_primes-1);
for (;;)
{
/* When generating ridiculously small keys, we can get stuck
* continually regenerating the same prime values. Check for
* this and bail if it happens 3 times. */
unsigned int degenerate = 0;
do
{
if(!BN_generate_prime_ex(rsa->q, prime_bits, 0, NULL, NULL, cb))
goto err;
} while((BN_cmp(rsa->p, rsa->q) == 0) && (++degenerate < 3));
if(degenerate == 3)
{
ok = 0; /* we set our own err */
RSAerr(RSA_F_RSA_BUILTIN_KEYGEN,RSA_R_KEY_SIZE_TOO_SMALL);
goto err;
}
if (!BN_sub(r2,rsa->q,BN_value_one())) goto err;
if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
if (BN_is_one(r1))
break;
if(!BN_GENCB_call(cb, 2, n++))
goto err;
}
if(!BN_GENCB_call(cb, 3, 1))
goto err;
if (!BN_mul(rsa->n,rsa->p,rsa->q,ctx))
goto err;
for (i = 2; i < num_primes; i++)
{
RSA_additional_prime *ap = sk_RSA_additional_prime_value(additional_primes, i - 2);
prime_bits = ((bits - BN_num_bits(rsa->n))+(num_primes-(i+1)))/(num_primes-i);
for (;;)
{
if (!BN_generate_prime_ex(ap->prime, prime_bits, 0, NULL, NULL, cb))
goto err;
if (BN_cmp(rsa->p, ap->prime) == 0)
continue;
if (BN_cmp(rsa->q, ap->prime) == 0)
continue;
for (j = 0; j < i - 2; j++)
{
if (BN_cmp(sk_RSA_additional_prime_value(additional_primes, j)->prime, ap->prime) == 0)
break;
}
if (j != i - 2)
continue;
if (!BN_sub(r2, ap->prime, BN_value_one()))
goto err;
if (!BN_gcd(r1, r2, rsa->e, ctx))
goto err;
if (!BN_is_one(r1))
continue;
if (i != num_primes - 1)
break;
/* For the last prime we'll check that it makes
* n large enough. In the two prime case this isn't a
* problem because we generate primes with the top two
* bits set and so the product is always of the
* expected size. In the multi prime case, this doesn't
* follow. */
if (!BN_mul(r1, rsa->n, ap->prime, ctx))
goto err;
if (BN_num_bits(r1) == bits)
break;
if(!BN_GENCB_call(cb, 2, n++))
goto err;
}
/* ap->r is is the product of all the primes prior to the
* current one (including p and q). */
if (!BN_copy(ap->r, rsa->n))
goto err;
if (i == num_primes - 1)
{
/* In the case of the last prime, we calculated n in r1
* in the loop above. */
if (!BN_copy(rsa->n, r1))
goto err;
}
else
{
if (!BN_mul(rsa->n, rsa->n, ap->prime, ctx))
goto err;
}
if(!BN_GENCB_call(cb, 3, 1))
goto err;
}
if (BN_cmp(rsa->p,rsa->q) < 0)
{
tmp=rsa->p;
rsa->p=rsa->q;
rsa->q=tmp;
}
/* calculate d */
if (!BN_sub(r1,rsa->p,BN_value_one())) goto err; /* p-1 */
if (!BN_sub(r2,rsa->q,BN_value_one())) goto err; /* q-1 */
if (!BN_mul(r0,r1,r2,ctx)) goto err; /* (p-1)(q-1) */
for (i = 2; i < num_primes; i++)
{
RSA_additional_prime *ap = sk_RSA_additional_prime_value(additional_primes, i - 2);
if (!BN_sub(r3, ap->prime, BN_value_one()))
goto err;
if (!BN_mul(r0, r0, r3, ctx))
goto err;
}
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
{
pr0 = &local_r0;
BN_with_flags(pr0, r0, BN_FLG_CONSTTIME);
}
else
pr0 = r0;
if (!BN_mod_inverse(rsa->d,rsa->e,pr0,ctx)) goto err; /* d */
/* set up d for correct BN_FLG_CONSTTIME flag */
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
{
d = &local_d;
BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
}
else
d = rsa->d;
/* calculate d mod (p-1) */
if (!BN_mod(rsa->dmp1,d,r1,ctx)) goto err;
/* calculate d mod (q-1) */
if (!BN_mod(rsa->dmq1,d,r2,ctx)) goto err;
/* calculate inverse of q mod p */
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
{
p = &local_p;
BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);
}
else
p = rsa->p;
if (!BN_mod_inverse(rsa->iqmp,rsa->q,p,ctx)) goto err;
for (i = 2; i < num_primes; i++)
{
RSA_additional_prime *ap = sk_RSA_additional_prime_value(additional_primes, i - 2);
if (!BN_sub(ap->exp, ap->prime, BN_value_one()))
goto err;
if (!BN_mod(ap->exp, rsa->d, ap->exp, ctx))
goto err;
if (!BN_mod_inverse(ap->coeff, ap->r, ap->prime, ctx))
goto err;
}
ok=1;
rsa->additional_primes = additional_primes;
additional_primes = NULL;
err:
if (ok == -1)
{
RSAerr(RSA_F_RSA_BUILTIN_KEYGEN,ERR_LIB_BN);
ok=0;
}
if (ctx != NULL)
{
BN_CTX_end(ctx);
BN_CTX_free(ctx);
}
if (additional_primes != NULL)
{
for (i = 0; i < sk_RSA_additional_prime_num(additional_primes); i++)
{
RSA_additional_prime *ap = sk_RSA_additional_prime_value(additional_primes, i);
if (ap->prime != NULL)
BN_clear_free(ap->prime);
if (ap->exp != NULL)
BN_clear_free(ap->exp);
if (ap->coeff != NULL)
BN_clear_free(ap->coeff);
if (ap->r != NULL)
BN_clear_free(ap->r);
}
sk_RSA_additional_prime_pop_free(additional_primes, int_rsa_free_additional_prime);
}
return ok;
}
/* signing */
static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
unsigned char *to, RSA *rsa, int padding)
{
BIGNUM *f, *ret, *br, *res;
int i,j,k,num=0,r= -1;
unsigned char *buf=NULL;
BN_CTX *ctx=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_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, &br, &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->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_EXP_CONSTTIME))
{
BN_init(&local_d);
d = &local_d;
BN_with_flags(d, rsa->d, BN_FLG_EXP_CONSTTIME);
}
else
d = rsa->d;
MONT_HELPER(rsa, ctx, 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 (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(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 generate_key(DH *dh)
{
int ok=0;
int generate_new_key=0;
unsigned l;
BN_CTX *ctx;
BN_MONT_CTX *mont=NULL;
BIGNUM *pub_key=NULL,*priv_key=NULL;
if (FIPS_mode() && (BN_num_bits(dh->p) < OPENSSL_DH_FIPS_MIN_MODULUS_BITS))
{
DHerr(DH_F_GENERATE_KEY, DH_R_KEY_SIZE_TOO_SMALL);
return 0;
}
ctx = BN_CTX_new();
if (ctx == NULL) goto err;
if (dh->priv_key == NULL)
{
priv_key=BN_new();
if (priv_key == NULL) goto err;
generate_new_key=1;
}
else
priv_key=dh->priv_key;
if (dh->pub_key == NULL)
{
pub_key=BN_new();
if (pub_key == NULL) goto err;
}
else
pub_key=dh->pub_key;
if (dh->flags & DH_FLAG_CACHE_MONT_P)
{
mont = BN_MONT_CTX_set_locked(
(BN_MONT_CTX **)&dh->method_mont_p,
CRYPTO_LOCK_DH, dh->p, ctx);
if (!mont)
goto err;
}
if (generate_new_key)
{
l = dh->length ? dh->length : BN_num_bits(dh->p)-1; /* secret exponent length */
if (!BN_rand(priv_key, l, 0, 0)) goto err;
}
{
BIGNUM local_prk;
BIGNUM *prk;
if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0)
{
BN_init(&local_prk);
prk = &local_prk;
BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
}
else
prk = priv_key;
if (!dh->meth->bn_mod_exp(dh, pub_key, dh->g, prk, dh->p, ctx, mont))
goto err;
}
dh->pub_key=pub_key;
dh->priv_key=priv_key;
ok=1;
err:
if (ok != 1)
DHerr(DH_F_GENERATE_KEY,ERR_R_BN_LIB);
if ((pub_key != NULL) && (dh->pub_key == NULL)) BN_free(pub_key);
if ((priv_key != NULL) && (dh->priv_key == NULL)) BN_free(priv_key);
BN_CTX_free(ctx);
return(ok);
}
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;
BIGNUM *dmp1, *dmq1;
int ret=0;
BN_CTX_start(ctx);
r1 = BN_CTX_get(ctx);
m1 = BN_CTX_get(ctx);
vrfy = BN_CTX_get(ctx);
MONT_HELPER(rsa, ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
MONT_HELPER(rsa, ctx, q, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
if (!BN_mod(r1,I,rsa->q,ctx)) goto err;
if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
{
dmq1 = &local_dmq1;
BN_with_flags(dmq1, rsa->dmq1, BN_FLG_EXP_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->flags & RSA_FLAG_NO_EXP_CONSTTIME))
{
dmp1 = &local_dmp1;
BN_with_flags(dmp1, rsa->dmp1, BN_FLG_EXP_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;
if (!BN_mod(r0,r1,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_EXP_CONSTTIME))
{
d = &local_d;
BN_with_flags(d, rsa->d, BN_FLG_EXP_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);
}
int rsa_default_private_transform(RSA *rsa, uint8_t *out, const uint8_t *in,
size_t len) {
BIGNUM *f, *result;
BN_CTX *ctx = NULL;
unsigned blinding_index = 0;
BN_BLINDING *blinding = NULL;
int ret = 0;
ctx = BN_CTX_new();
if (ctx == NULL) {
goto err;
}
BN_CTX_start(ctx);
f = BN_CTX_get(ctx);
result = BN_CTX_get(ctx);
if (f == NULL || result == NULL) {
OPENSSL_PUT_ERROR(RSA, ERR_R_MALLOC_FAILURE);
goto err;
}
if (BN_bin2bn(in, len, f) == NULL) {
goto err;
}
if (BN_ucmp(f, rsa->n) >= 0) {
/* Usually the padding functions would catch this. */
OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
goto err;
}
if (!(rsa->flags & RSA_FLAG_NO_BLINDING)) {
blinding = rsa_blinding_get(rsa, &blinding_index, ctx);
if (blinding == NULL) {
OPENSSL_PUT_ERROR(RSA, ERR_R_INTERNAL_ERROR);
goto err;
}
if (!BN_BLINDING_convert_ex(f, NULL, blinding, 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->mod_exp(result, f, rsa, ctx)) {
goto err;
}
} else {
BIGNUM local_d;
BIGNUM *d = NULL;
BN_init(&local_d);
d = &local_d;
BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) {
if (BN_MONT_CTX_set_locked(&rsa->mont_n, &rsa->lock, rsa->n, ctx) ==
NULL) {
goto err;
}
}
if (!rsa->meth->bn_mod_exp(result, f, d, rsa->n, ctx, rsa->mont_n)) {
goto err;
}
}
if (blinding) {
if (!BN_BLINDING_invert_ex(result, NULL, blinding, ctx)) {
goto err;
}
}
if (!BN_bn2bin_padded(out, len, result)) {
OPENSSL_PUT_ERROR(RSA, ERR_R_INTERNAL_ERROR);
goto err;
}
ret = 1;
err:
if (ctx != NULL) {
BN_CTX_end(ctx);
BN_CTX_free(ctx);
}
if (blinding != NULL) {
rsa_blinding_release(rsa, blinding, blinding_index);
}
return ret;
}
static int 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;
size_t i, num_additional_primes = 0;
if (rsa->additional_primes != NULL) {
num_additional_primes = sk_RSA_additional_prime_num(rsa->additional_primes);
}
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) */
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->flags & RSA_FLAG_CACHE_PRIVATE) {
if (BN_MONT_CTX_set_locked(&rsa->_method_mod_p, &rsa->lock, p, ctx) ==
NULL) {
goto err;
}
if (BN_MONT_CTX_set_locked(&rsa->_method_mod_q, &rsa->lock, q, ctx) ==
NULL) {
goto err;
}
}
}
if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) {
if (BN_MONT_CTX_set_locked(&rsa->_method_mod_n, &rsa->lock, rsa->n, ctx) ==
NULL) {
goto err;
}
}
/* compute I mod q */
c = &local_c;
BN_with_flags(c, I, BN_FLG_CONSTTIME);
if (!BN_mod(r1, c, rsa->q, ctx)) {
goto err;
}
/* compute r1^dmq1 mod q */
dmq1 = &local_dmq1;
BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
if (!rsa->meth->bn_mod_exp(m1, r1, dmq1, rsa->q, ctx, rsa->_method_mod_q)) {
goto err;
}
/* compute I mod p */
c = &local_c;
BN_with_flags(c, I, BN_FLG_CONSTTIME);
if (!BN_mod(r1, c, rsa->p, ctx)) {
goto err;
}
/* compute r1^dmp1 mod p */
dmp1 = &local_dmp1;
BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
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 */
pr1 = &local_r1;
BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
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;
}
for (i = 0; i < num_additional_primes; i++) {
/* multi-prime RSA. */
BIGNUM local_exp, local_prime;
BIGNUM *exp = &local_exp, *prime = &local_prime;
RSA_additional_prime *ap =
sk_RSA_additional_prime_value(rsa->additional_primes, i);
BN_with_flags(exp, ap->exp, BN_FLG_CONSTTIME);
BN_with_flags(prime, ap->prime, BN_FLG_CONSTTIME);
/* c will already point to a BIGNUM with the correct flags. */
if (!BN_mod(r1, c, prime, ctx)) {
goto err;
}
if ((rsa->flags & RSA_FLAG_CACHE_PRIVATE) &&
!BN_MONT_CTX_set_locked(&ap->method_mod, &rsa->lock, prime, ctx)) {
goto err;
}
if (!rsa->meth->bn_mod_exp(m1, r1, exp, prime, ctx, ap->method_mod)) {
goto err;
}
BN_set_flags(m1, BN_FLG_CONSTTIME);
if (!BN_sub(m1, m1, r0) ||
!BN_mul(m1, m1, ap->coeff, ctx) ||
!BN_mod(m1, m1, prime, ctx) ||
(BN_is_negative(m1) && !BN_add(m1, m1, prime)) ||
!BN_mul(m1, m1, ap->r, ctx) ||
!BN_add(r0, r0, 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;
d = &local_d;
BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
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_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 (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_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);
}
