CONFIG_CRYPTO_DRBG (not configurable)

modulename: drbg.ko

configname: CONFIG_CRYPTO_DRBG

Linux Kernel Configuration
└─>Cryptographic API
└─>NIST SP800-90A DRBG
└─>CRYPTO_DRBG
In linux kernel since version 3.10 (release Date: 2013-06-30)  
source code:
crypto/drbg.c