HMAC support

modulename: hmac.ko

configname: CONFIG_CRYPTO_HMAC

Linux Kernel Configuration
└─>Cryptographic options
└─>HMAC support
In linux kernel since version 2.6.12  
HMAC: Keyed-Hashing for Message Authentication (RFC2104).
This is required for IPSec.

source code:
crypto/hmac.c

depends
CONFIG_CRYPTO

is selected by
CONFIG_RPCSEC_GSS_KRB5