Re: [dpdk-dev] [EXT] Re: [PATCH v2 1/3] cryptodev: remove LIST_END enumerators

["Kinsella, Ray" <mdr@ashroe.eu>]

On 12/10/2021 11:50, Anoob Joseph wrote:
> Hi Ray, Akhil,
> 
> Please see inline.
> 
> Thanks,
> Anoob
> 
>> -----Original Message-----
>> From: Akhil Goyal <gakhil@marvell.com>
>> Sent: Tuesday, October 12, 2021 3:49 PM
>> To: Kinsella, Ray <mdr@ashroe.eu>; dev@dpdk.org
>> Cc: thomas@monjalon.net; david.marchand@redhat.com;
>> hemant.agrawal@nxp.com; Anoob Joseph <anoobj@marvell.com>;
>> pablo.de.lara.guarch@intel.com; fiona.trahe@intel.com;
>> declan.doherty@intel.com; matan@nvidia.com; g.singh@nxp.com;
>> roy.fan.zhang@intel.com; jianjay.zhou@huawei.com; asomalap@amd.com;
>> ruifeng.wang@arm.com; konstantin.ananyev@intel.com;
>> radu.nicolau@intel.com; ajit.khaparde@broadcom.com; Nagadheeraj Rottela
>> <rnagadheeraj@marvell.com>; Ankur Dwivedi <adwivedi@marvell.com>;
>> ciara.power@intel.com; Stephen Hemminger <stephen@networkplumber.org>;
>> Yigit, Ferruh <ferruh.yigit@intel.com>
>> Subject: RE: [EXT] Re: [dpdk-dev] [PATCH v2 1/3] cryptodev: remove LIST_END
>> enumerators
>>
>>>
>>> On 08/10/2021 21:45, Akhil Goyal wrote:
>>>> Remove *_LIST_END enumerators from asymmetric crypto lib to avoid
>>>> ABI breakage for every new addition in enums.
>>>>
>>>> Signed-off-by: Akhil Goyal <gakhil@marvell.com>
>>>> ---
>>>> v2: no change
>>>>
>>>>  app/test/test_cryptodev_asym.c  | 4 ++--
>>>>  drivers/crypto/qat/qat_asym.c   | 2 +-
>>>>  lib/cryptodev/rte_crypto_asym.h | 4 ----
>>>>  3 files changed, 3 insertions(+), 7 deletions(-)
>>>>
>>>> diff --git a/app/test/test_cryptodev_asym.c
>>> b/app/test/test_cryptodev_asym.c
>>>> index 9d19a6d6d9..603b2e4609 100644
>>>> --- a/app/test/test_cryptodev_asym.c
>>>> +++ b/app/test/test_cryptodev_asym.c
>>>> @@ -541,7 +541,7 @@ test_one_case(const void *test_case, int
>>> sessionless)
>>>>  		printf("  %u) TestCase %s %s\n", test_index++,
>>>>  			tc.modex.description, test_msg);
>>>>  	} else {
>>>> -		for (i = 0; i < RTE_CRYPTO_ASYM_OP_LIST_END; i++) {
>>>> +		for (i = 0; i <=
>>> RTE_CRYPTO_ASYM_OP_SHARED_SECRET_COMPUTE; i++) {
>>>>  			if (tc.modex.xform_type ==
>>> RTE_CRYPTO_ASYM_XFORM_RSA) {
>>>>  				if (tc.rsa_data.op_type_flags & (1 << i)) {
>>>>  					if (tc.rsa_data.key_exp) {
>>>> @@ -1027,7 +1027,7 @@ static inline void print_asym_capa(
>>>>  			rte_crypto_asym_xform_strings[capa->xform_type]);
>>>>  	printf("operation supported -");
>>>>
>>>> -	for (i = 0; i < RTE_CRYPTO_ASYM_OP_LIST_END; i++) {
>>>> +	for (i = 0; i <= RTE_CRYPTO_ASYM_OP_SHARED_SECRET_COMPUTE;
>>> i++) {
>>>>  		/* check supported operations */
>>>>  		if
>>> (rte_cryptodev_asym_xform_capability_check_optype(capa, i))
>>>>  			printf(" %s",
>>>> diff --git a/drivers/crypto/qat/qat_asym.c
>>>> b/drivers/crypto/qat/qat_asym.c index 85973812a8..026625a4d2 100644
>>>> --- a/drivers/crypto/qat/qat_asym.c
>>>> +++ b/drivers/crypto/qat/qat_asym.c
>>>> @@ -742,7 +742,7 @@ qat_asym_session_configure(struct rte_cryptodev
>>> *dev,
>>>>  			err = -EINVAL;
>>>>  			goto error;
>>>>  		}
>>>> -	} else if (xform->xform_type >=
>>> RTE_CRYPTO_ASYM_XFORM_TYPE_LIST_END
>>>> +	} else if (xform->xform_type > RTE_CRYPTO_ASYM_XFORM_ECPM
>>>>  			|| xform->xform_type <=
>>> RTE_CRYPTO_ASYM_XFORM_NONE) {
>>>>  		QAT_LOG(ERR, "Invalid asymmetric crypto xform");
>>>>  		err = -EINVAL;
>>>> diff --git a/lib/cryptodev/rte_crypto_asym.h
>>> b/lib/cryptodev/rte_crypto_asym.h
>>>> index 9c866f553f..5edf658572 100644
>>>> --- a/lib/cryptodev/rte_crypto_asym.h
>>>> +++ b/lib/cryptodev/rte_crypto_asym.h
>>>> @@ -94,8 +94,6 @@ enum rte_crypto_asym_xform_type {
>>>>  	 */
>>>>  	RTE_CRYPTO_ASYM_XFORM_ECPM,
>>>>  	/**< Elliptic Curve Point Multiplication */
>>>> -	RTE_CRYPTO_ASYM_XFORM_TYPE_LIST_END
>>>> -	/**< End of list */
>>>>  };
>>>>
>>>>  /**
>>>> @@ -116,7 +114,6 @@ enum rte_crypto_asym_op_type {
>>>>  	/**< DH Public Key generation operation */
>>>>  	RTE_CRYPTO_ASYM_OP_SHARED_SECRET_COMPUTE,
>>>>  	/**< DH Shared Secret compute operation */
>>>> -	RTE_CRYPTO_ASYM_OP_LIST_END
>>>>  };
>>>>
>>>>  /**
>>>> @@ -133,7 +130,6 @@ enum rte_crypto_rsa_padding_type {
>>>>  	/**< RSA PKCS#1 OAEP padding scheme */
>>>>  	RTE_CRYPTO_RSA_PADDING_PSS,
>>>>  	/**< RSA PKCS#1 PSS padding scheme */
>>>> -	RTE_CRYPTO_RSA_PADDING_TYPE_LIST_END
>>>>  };
>>>>
>>>>  /**
>>>
>>> So I am not sure that this is an improvement.
>>> The cryptodev issue we had, was that _LIST_END was being used to size
>>> arrays.
>>> And that broke when new algorithms got added. Is that an issue, in this case?
>>
>> Yes we did this same exercise for symmetric crypto enums earlier.
>> Asym enums were left as it was experimental at that point.
>> They are still experimental, but thought of making this uniform throughout DPDK
>> enums.
>>
>>>
>>> I am not sure that swapping out _LIST_END, and then littering the code
>>> with RTE_CRYPTO_ASYM_XFORM_ECPM and
>>> RTE_CRYPTO_ASYM_OP_SHARED_SECRET_COMPUTE, is an improvement
>> here.
>>>
>>> My 2c is that from an ABI PoV RTE_CRYPTO_ASYM_OP_LIST_END is not
>>> better or worse, than RTE_CRYPTO_ASYM_OP_SHARED_SECRET_COMPUTE?
>>>
>>> Interested to hear other thoughts.
>>
>> I don’t have any better solution for avoiding ABI issues for now.
>> The change is for avoiding ABI breakage. But we can drop this patch For now as
>> asym is still experimental.
> 
> [Anoob] Having LIST_END would preclude new additions to asymmetric algos? If yes, then I would suggest we address it now.

Not at all - but it can be problematic, if two versions of DPDK disagree with the value of LIST_END.

> Looking at the "problematic changes", we only have 2-3 application & PMD changes. For unit test application, we could may be do something like,

The essental functionality not that different, I am just not sure that the verbosity below is helping. 
What you are really trying to guard against is people using LIST_END to size arrays.

> 
> -               for (i = 0; i < RTE_CRYPTO_ASYM_OP_LIST_END; i++) {
> +               enum rte_crypto_asym_op_type types[] = {
> +                               RTE_CRYPTO_ASYM_OP_ENCRYPT,
> +                               RTE_CRYPTO_ASYM_OP_DECRYPT,
> +                               RTE_CRYPTO_ASYM_OP_SIGN,
> +                               RTE_CRYPTO_ASYM_OP_VERIFY,
> +                               RTE_CRYPTO_ASYM_OP_PRIVATE_KEY_GENERATE,
> +                               RTE_CRYPTO_ASYM_OP_PUBLIC_KEY_GENERATE,
> +                               RTE_CRYPTO_ASYM_OP_SHARED_SECRET_COMPUTE,
> +               };
> +               for (i = 0; i <= RTE_DIM(types); i++) {
>                         if (tc.modex.xform_type == RTE_CRYPTO_ASYM_XFORM_RSA) {
> -                               if (tc.rsa_data.op_type_flags & (1 << i)) {
> +                               if (tc.rsa_data.op_type_flags & (1 << types[i])) {
>                                         if (tc.rsa_data.key_exp) {
>                                                 status = test_cryptodev_asym_op(
>                                                         &testsuite_params, &tc,
> -                                                       test_msg, sessionless, i,
> +                                                       test_msg, sessionless, types[i],
>                                                         RTE_RSA_KEY_TYPE_EXP);
>                                         }
>                                         if (status)
>                                                 break;
> -                                       if (tc.rsa_data.key_qt && (i ==
> +                                       if (tc.rsa_data.key_qt && (types[i] ==
>                                                         RTE_CRYPTO_ASYM_OP_DECRYPT ||
> -                                                       i == RTE_CRYPTO_ASYM_OP_SIGN)) {
> +                                                       types[i] == RTE_CRYPTO_ASYM_OP_SIGN)) {
>                                                 status = test_cryptodev_asym_op(
>                                                         &testsuite_params,
> -                                                       &tc, test_msg, sessionless, i,
> +                                                       &tc, test_msg, sessionless, types[i],
>                                                         RTE_RSA_KET_TYPE_QT);
>                                         }
>                                         if (status)
> 
> This way, application would only use the ones which it is designed to work with. For QAT driver changes, we could have an overload if condition (if alg == x || alg = y || ...) to get the same effect. 
>