Skip to content

Commit

Permalink
DH_check_pub_key() should not fail when setting result code
Browse files Browse the repository at this point in the history 
The semantics of ossl_ffc_validate_public_key() and
ossl_ffc_validate_public_key_partial() needs to be changed
to not return error on non-fatal problems.

Fixes openssl#22287

Reviewed-by: Todd Short <[email protected]>
Reviewed-by: Paul Dale <[email protected]>
(Merged from openssl#22291)
  • Loading branch information
@t8m
t8m committed Oct 11, 2023
1 parent 715242b commit eaee176
Show file tree
Hide file tree
Showing 5 changed files with 30 additions and 35 deletions.
3 changes: 2 additions & 1 deletion crypto/dh/dh_check.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -259,7 +259,8 @@ int DH_check_pub_key(const DH *dh, const BIGNUM *pub_key, int *ret)
*/
int ossl_dh_check_pub_key_partial(const DH *dh, const BIGNUM *pub_key, int *ret)
{
return ossl_ffc_validate_public_key_partial(&dh->params, pub_key, ret);
return ossl_ffc_validate_public_key_partial(&dh->params, pub_key, ret)
&& *ret == 0;
}

int ossl_dh_check_priv_key(const DH *dh, const BIGNUM *priv_key, int *ret)
Expand Down
6 changes: 4 additions & 2 deletions crypto/dsa/dsa_check.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -39,7 +39,8 @@ int ossl_dsa_check_params(const DSA *dsa, int checktype, int *ret)
*/
int ossl_dsa_check_pub_key(const DSA *dsa, const BIGNUM *pub_key, int *ret)
{
return ossl_ffc_validate_public_key(&dsa->params, pub_key, ret);
return ossl_ffc_validate_public_key(&dsa->params, pub_key, ret)
&& *ret == 0;
}

/*
Expand All @@ -49,7 +50,8 @@ int ossl_dsa_check_pub_key(const DSA *dsa, const BIGNUM *pub_key, int *ret)
*/
int ossl_dsa_check_pub_key_partial(const DSA *dsa, const BIGNUM *pub_key, int *ret)
{
return ossl_ffc_validate_public_key_partial(&dsa->params, pub_key, ret);
return ossl_ffc_validate_public_key_partial(&dsa->params, pub_key, ret)
&& *ret == 0;
}

int ossl_dsa_check_priv_key(const DSA *dsa, const BIGNUM *priv_key, int *ret)
Expand Down
16 changes: 5 additions & 11 deletions crypto/ffc/ffc_key_validate.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -26,7 +26,7 @@ int ossl_ffc_validate_public_key_partial(const FFC_PARAMS *params,
*ret = 0;
if (params == NULL || pub_key == NULL || params->p == NULL) {
*ret = FFC_ERROR_PASSED_NULL_PARAM;
return 0;
return 1;
}

ctx = BN_CTX_new_ex(NULL);
Expand All @@ -39,18 +39,14 @@ int ossl_ffc_validate_public_key_partial(const FFC_PARAMS *params,
if (tmp == NULL
|| !BN_set_word(tmp, 1))
goto err;
if (BN_cmp(pub_key, tmp) <= 0) {
if (BN_cmp(pub_key, tmp) <= 0)
*ret |= FFC_ERROR_PUBKEY_TOO_SMALL;
goto err;
}
/* Step(1): Verify pub_key <= p-2 */
if (BN_copy(tmp, params->p) == NULL
|| !BN_sub_word(tmp, 1))
goto err;
if (BN_cmp(pub_key, tmp) >= 0) {
if (BN_cmp(pub_key, tmp) >= 0)
*ret |= FFC_ERROR_PUBKEY_TOO_LARGE;
goto err;
}
ok = 1;
err:
if (ctx != NULL) {
Expand All @@ -73,7 +69,7 @@ int ossl_ffc_validate_public_key(const FFC_PARAMS *params,
if (!ossl_ffc_validate_public_key_partial(params, pub_key, ret))
return 0;

if (params->q != NULL) {
if (*ret == 0 && params->q != NULL) {
ctx = BN_CTX_new_ex(NULL);
if (ctx == NULL)
goto err;
Expand All @@ -84,10 +80,8 @@ int ossl_ffc_validate_public_key(const FFC_PARAMS *params,
if (tmp == NULL
|| !BN_mod_exp(tmp, pub_key, params->q, params->p, ctx))
goto err;
if (!BN_is_one(tmp)) {
if (!BN_is_one(tmp))
*ret |= FFC_ERROR_PUBKEY_INVALID;
goto err;
}
}

ok = 1;
Expand Down
2 changes: 1 addition & 1 deletion providers/implementations/keymgmt/dh_kmgmt.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -392,7 +392,7 @@ static int dh_validate_public(const DH *dh, int checktype)
&& ossl_dh_is_named_safe_prime_group(dh))
return ossl_dh_check_pub_key_partial(dh, pub_key, &res);

return DH_check_pub_key(dh, pub_key, &res);
return DH_check_pub_key_ex(dh, pub_key);
}

static int dh_validate_private(const DH *dh)
Expand Down
38 changes: 18 additions & 20 deletions test/ffc_internal_test.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -455,22 +455,20 @@ static int ffc_public_validate_test(void)
if (!TEST_true(BN_set_word(pub, 1)))
goto err;
BN_set_negative(pub, 1);
/* Fail if public key is negative */
if (!TEST_false(ossl_ffc_validate_public_key(params, pub, &res)))
/* Check must succeed but set res if public key is negative */
if (!TEST_true(ossl_ffc_validate_public_key(params, pub, &res)))
goto err;
if (!TEST_int_eq(FFC_ERROR_PUBKEY_TOO_SMALL, res))
goto err;
if (!TEST_true(BN_set_word(pub, 0)))
goto err;
if (!TEST_int_eq(FFC_ERROR_PUBKEY_TOO_SMALL, res))
goto err;
/* Fail if public key is zero */
if (!TEST_false(ossl_ffc_validate_public_key(params, pub, &res)))
/* Check must succeed but set res if public key is zero */
if (!TEST_true(ossl_ffc_validate_public_key(params, pub, &res)))
goto err;
if (!TEST_int_eq(FFC_ERROR_PUBKEY_TOO_SMALL, res))
goto err;
/* Fail if public key is 1 */
if (!TEST_false(ossl_ffc_validate_public_key(params, BN_value_one(), &res)))
/* Check must succeed but set res if public key is 1 */
if (!TEST_true(ossl_ffc_validate_public_key(params, BN_value_one(), &res)))
goto err;
if (!TEST_int_eq(FFC_ERROR_PUBKEY_TOO_SMALL, res))
goto err;
Expand All @@ -482,24 +480,24 @@ static int ffc_public_validate_test(void)

if (!TEST_ptr(BN_copy(pub, params->p)))
goto err;
/* Fail if public key = p */
if (!TEST_false(ossl_ffc_validate_public_key(params, pub, &res)))
/* Check must succeed but set res if public key = p */
if (!TEST_true(ossl_ffc_validate_public_key(params, pub, &res)))
goto err;
if (!TEST_int_eq(FFC_ERROR_PUBKEY_TOO_LARGE, res))
goto err;

if (!TEST_true(BN_sub_word(pub, 1)))
goto err;
/* Fail if public key = p - 1 */
if (!TEST_false(ossl_ffc_validate_public_key(params, pub, &res)))
/* Check must succeed but set res if public key = p - 1 */
if (!TEST_true(ossl_ffc_validate_public_key(params, pub, &res)))
goto err;
if (!TEST_int_eq(FFC_ERROR_PUBKEY_TOO_LARGE, res))
goto err;

if (!TEST_true(BN_sub_word(pub, 1)))
goto err;
/* Fail if public key is not related to p & q */
if (!TEST_false(ossl_ffc_validate_public_key(params, pub, &res)))
/* Check must succeed but set res if public key is not related to p & q */
if (!TEST_true(ossl_ffc_validate_public_key(params, pub, &res)))
goto err;
if (!TEST_int_eq(FFC_ERROR_PUBKEY_INVALID, res))
goto err;
Expand All @@ -510,23 +508,23 @@ static int ffc_public_validate_test(void)
if (!TEST_true(ossl_ffc_validate_public_key(params, pub, &res)))
goto err;

/* Fail if params is NULL */
if (!TEST_false(ossl_ffc_validate_public_key(NULL, pub, &res)))
/* Check must succeed but set res if params is NULL */
if (!TEST_true(ossl_ffc_validate_public_key(NULL, pub, &res)))
goto err;
if (!TEST_int_eq(FFC_ERROR_PASSED_NULL_PARAM, res))
goto err;
res = -1;
/* Fail if pubkey is NULL */
if (!TEST_false(ossl_ffc_validate_public_key(params, NULL, &res)))
/* Check must succeed but set res if pubkey is NULL */
if (!TEST_true(ossl_ffc_validate_public_key(params, NULL, &res)))
goto err;
if (!TEST_int_eq(FFC_ERROR_PASSED_NULL_PARAM, res))
goto err;
res = -1;

BN_free(params->p);
params->p = NULL;
/* Fail if params->p is NULL */
if (!TEST_false(ossl_ffc_validate_public_key(params, pub, &res)))
/* Check must succeed but set res if params->p is NULL */
if (!TEST_true(ossl_ffc_validate_public_key(params, pub, &res)))
goto err;
if (!TEST_int_eq(FFC_ERROR_PASSED_NULL_PARAM, res))
goto err;
Expand Down

0 comments on commit eaee176

Please sign in to comment.