2. AESN-NI Multi Buffer Crypto Poll Mode Driver

The AESNI MB PMD (librte_pmd_aesni_mb) provides poll mode crypto driver support for utilizing Intel multi buffer library, see the white paper Fast Multi-buffer IPsec Implementations on IntelĀ® Architecture Processors.

The AES-NI MB PMD has current only been tested on Fedora 21 64-bit with gcc.

2.1. Features

AESNI MB PMD has support for:

Cipher algorithms:

  • RTE_CRYPTO_CIPHER_AES128_CBC
  • RTE_CRYPTO_CIPHER_AES192_CBC
  • RTE_CRYPTO_CIPHER_AES256_CBC
  • RTE_CRYPTO_CIPHER_AES128_CTR
  • RTE_CRYPTO_CIPHER_AES192_CTR
  • RTE_CRYPTO_CIPHER_AES256_CTR
  • RTE_CRYPTO_CIPHER_AES_DOCSISBPI

Hash algorithms:

  • RTE_CRYPTO_HASH_MD5_HMAC
  • RTE_CRYPTO_HASH_SHA1_HMAC
  • RTE_CRYPTO_HASH_SHA224_HMAC
  • RTE_CRYPTO_HASH_SHA256_HMAC
  • RTE_CRYPTO_HASH_SHA384_HMAC
  • RTE_CRYPTO_HASH_SHA512_HMAC
  • RTE_CRYPTO_HASH_AES_XCBC_HMAC

2.2. Limitations

  • Chained mbufs are not supported.
  • Only in-place is currently supported (destination address is the same as source address).
  • Only supports session-oriented API implementation (session-less APIs are not supported).

2.3. Installation

To build DPDK with the AESNI_MB_PMD the user is required to download the multi-buffer library from here and compile it on their user system before building DPDK. The latest version of the library supported by this PMD is v0.45, which can be downloaded in https://github.com/01org/intel-ipsec-mb/archive/v0.45.zip.

make

As a reference, the following table shows a mapping between the past DPDK versions and the Multi-Buffer library version supported by them:

Table 2.1 DPDK and Multi-Buffer library version compatibility
DPDK version Multi-buffer library version
2.2 - 16.11 0.43 - 0.44
17.02 0.44
17.05 0.45

2.4. Initialization

In order to enable this virtual crypto PMD, user must:

  • Export the environmental variable AESNI_MULTI_BUFFER_LIB_PATH with the path where the library was extracted.
  • Build the multi buffer library (explained in Installation section).
  • Set CONFIG_RTE_LIBRTE_PMD_AESNI_MB=y in config/common_base.

To use the PMD in an application, user must:

  • Call rte_eal_vdev_init(“crypto_aesni_mb”) within the application.
  • Use –vdev=”crypto_aesni_mb” in the EAL options, which will call rte_eal_vdev_init() internally.

The following parameters (all optional) can be provided in the previous two calls:

  • socket_id: Specify the socket where the memory for the device is going to be allocated (by default, socket_id will be the socket where the core that is creating the PMD is running on).
  • max_nb_queue_pairs: Specify the maximum number of queue pairs in the device (8 by default).
  • max_nb_sessions: Specify the maximum number of sessions that can be created (2048 by default).

Example:

./l2fwd-crypto -l 6 -n 4 --vdev="crypto_aesni_mb,socket_id=1,max_nb_sessions=128"