diff -up openssl-1.0.2k/crypto/rsa/rsa_gen.c.gen-timing openssl-1.0.2k/crypto/rsa/rsa_gen.c
--- openssl-1.0.2k/crypto/rsa/rsa_gen.c.gen-timing 2018-06-18 13:46:24.323138691 +0200
+++ openssl-1.0.2k/crypto/rsa/rsa_gen.c 2018-06-18 14:53:26.361975922 +0200
@@ -1,6 +1,6 @@
/* crypto/rsa/rsa_gen.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
- * Copyright (C) 2013 Red Hat, Inc.
+ * Copyright (C) 2013, 2018 Red Hat, Inc.
* All rights reserved.
*
* This package is an SSL implementation written
@@ -175,14 +175,13 @@ static int FIPS_rsa_builtin_keygen(RSA *
BN_GENCB *cb)
{
BIGNUM *r0 = NULL, *r1 = NULL, *r2 = NULL, *r3 = NULL, *tmp;
- BIGNUM local_r0, local_d, local_p;
- BIGNUM *pr0, *d, *p;
BN_CTX *ctx = NULL;
int ok = -1;
int i;
int n = 0;
int test = 0;
int pbits = bits / 2;
+ unsigned long error = 0;
if (FIPS_selftest_failed()) {
FIPSerr(FIPS_F_RSA_BUILTIN_KEYGEN, FIPS_R_FIPS_SELFTEST_FAILED);
@@ -251,6 +250,12 @@ static int FIPS_rsa_builtin_keygen(RSA *
if (!BN_is_zero(rsa->p) && !BN_is_zero(rsa->q))
test = 1;
+ BN_set_flags(r0, BN_FLG_CONSTTIME);
+ BN_set_flags(r1, BN_FLG_CONSTTIME);
+ BN_set_flags(r2, BN_FLG_CONSTTIME);
+ BN_set_flags(rsa->p, BN_FLG_CONSTTIME);
+ BN_set_flags(rsa->q, BN_FLG_CONSTTIME);
+
retry:
/* generate p and q */
for (i = 0; i < 5 * pbits; i++) {
@@ -266,9 +271,9 @@ static int FIPS_rsa_builtin_keygen(RSA *
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)) {
+ ERR_set_mark();
+ if (BN_mod_inverse(r1, r2, rsa->e, ctx) != NULL) {
+ /* GCD == 1 since inverse exists */
int r;
r = BN_is_prime_fasttest_ex(rsa->p, pbits > 1024 ? 4 : 5, ctx, 0,
cb);
@@ -276,8 +281,16 @@ static int FIPS_rsa_builtin_keygen(RSA *
goto err;
if (r > 0)
break;
+ } else {
+ error = ERR_peek_last_error();
+ if (ERR_GET_LIB(error) == ERR_LIB_BN
+ && ERR_GET_REASON(error) == BN_R_NO_INVERSE) {
+ /* GCD != 1 */
+ ERR_pop_to_mark();
+ } else {
+ goto err;
+ }
}
-
if (!BN_GENCB_call(cb, 2, n++))
goto err;
}
@@ -309,9 +322,9 @@ static int FIPS_rsa_builtin_keygen(RSA *
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)) {
+ ERR_set_mark();
+ if (BN_mod_inverse(r1, r2, rsa->e, ctx) != NULL) {
+ /* GCD == 1 since inverse exists */
int r;
r = BN_is_prime_fasttest_ex(rsa->q, pbits > 1024 ? 4 : 5, ctx, 0,
cb);
@@ -319,8 +332,16 @@ static int FIPS_rsa_builtin_keygen(RSA *
goto err;
if (r > 0)
break;
+ } else {
+ error = ERR_peek_last_error();
+ if (ERR_GET_LIB(error) == ERR_LIB_BN
+ && ERR_GET_REASON(error) == BN_R_NO_INVERSE) {
+ /* GCD != 1 */
+ ERR_pop_to_mark();
+ } else {
+ goto err;
+ }
}
-
if (!BN_GENCB_call(cb, 2, n++))
goto err;
}
@@ -355,51 +376,44 @@ static int FIPS_rsa_builtin_keygen(RSA *
if (!BN_sub(r2, rsa->q, BN_value_one()))
goto err; /* q-1 */
+ /* note that computing gcd is not safe to timing attacks */
if (!BN_gcd(r0, r1, r2, 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_div(r0, NULL, r1, pr0, ctx))
- goto err;
- if (!BN_mul(r0, r0, r2, ctx))
- goto err; /* lcm(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 */
+
+ {
+ if (!BN_div(r0, NULL, r1, r0, ctx))
+ goto err;
+
+ if (!BN_mul(r0, r0, r2, ctx)) /* lcm(p-1, q-1) */
+ goto err;
+
+ if (!BN_mod_inverse(rsa->d, rsa->e, r0, ctx)) /* d */
+ goto err;
+ }
if (BN_num_bits(rsa->d) < pbits)
goto retry; /* d is too small */
- /* 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;
+ {
+ BIGNUM *d = BN_new();
- /* calculate d mod (p-1) */
- if (!BN_mod(rsa->dmp1, d, r1, ctx))
- goto err;
+ if (d == NULL)
+ goto err;
+ BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
- /* calculate d mod (q-1) */
- if (!BN_mod(rsa->dmq1, d, r2, ctx))
- goto err;
+ if (/* calculate d mod (p-1) */
+ !BN_mod(rsa->dmp1, d, r1, ctx)
+ /* calculate d mod (q-1) */
+ || !BN_mod(rsa->dmq1, d, r2, ctx)) {
+ BN_free(d);
+ goto err;
+ }
+ /* We MUST free d before any further use of rsa->d */
+ BN_free(d);
+ }
/* 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))
+ if (!BN_mod_inverse(rsa->iqmp, rsa->q, rsa->p, ctx))
goto err;
if (fips_rsa_pairwise_fail)
@@ -431,6 +445,17 @@ static int rsa_builtin_keygen(RSA *rsa,
BIGNUM *pr0, *d, *p;
int bitsp, bitsq, ok = -1, n = 0;
BN_CTX *ctx = NULL;
+ unsigned long error = 0;
+
+ /*
+ * When generating ridiculously small keys, we can get stuck
+ * continually regenerating the same prime values.
+ */
+ if (bits < 16) {
+ ok = 0; /* we set our own err */
+ RSAerr(RSA_F_RSA_BUILTIN_KEYGEN, RSA_R_KEY_SIZE_TOO_SMALL);
+ goto err;
+ }
#ifdef OPENSSL_FIPS
if (FIPS_module_mode()) {
@@ -483,45 +508,55 @@ static int rsa_builtin_keygen(RSA *rsa,
if (BN_copy(rsa->e, e_value) == NULL)
goto err;
+ BN_set_flags(rsa->p, BN_FLG_CONSTTIME);
+ BN_set_flags(rsa->q, BN_FLG_CONSTTIME);
+ BN_set_flags(r2, BN_FLG_CONSTTIME);
/* 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))
+ ERR_set_mark();
+ if (BN_mod_inverse(r1, r2, rsa->e, ctx) != NULL) {
+ /* GCD == 1 since inverse exists */
break;
+ }
+ error = ERR_peek_last_error();
+ if (ERR_GET_LIB(error) == ERR_LIB_BN
+ && ERR_GET_REASON(error) == BN_R_NO_INVERSE) {
+ /* GCD != 1 */
+ ERR_pop_to_mark();
+ } else {
+ goto err;
+ }
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;
if (!BN_sub(r2, rsa->q, rsa->p))
goto err;
- } while ((BN_ucmp(r2, r3) <= 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;
- }
+ } while (BN_ucmp(r2, r3) <= 0);
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))
+ ERR_set_mark();
+ if (BN_mod_inverse(r1, r2, rsa->e, ctx) != NULL) {
+ /* GCD == 1 since inverse exists */
break;
+ }
+ error = ERR_peek_last_error();
+ if (ERR_GET_LIB(error) == ERR_LIB_BN
+ && ERR_GET_REASON(error) == BN_R_NO_INVERSE) {
+ /* GCD != 1 */
+ ERR_pop_to_mark();
+ } else {
+ goto err;
+ }
if (!BN_GENCB_call(cb, 2, n++))
goto err;
}