Counter
struct
#
Counter is an SP 800-90A Rev. 1 CTR_DRBG instantiated with AES-256.
Per Table 3, it has a security strength of 256 bits, a seed size of 384 bits,
a counter length of 128 bits, a reseed interval of 2^48 requests, and a
maximum request size of 2^19 bits (2^16 bytes, 64 KiB).
We support a narrow range of parameters that fit the needs of our RNG:
AES-256, no derivation function, no personalization string, no prediction
resistance, and 384-bit additional input.
type Counter struct {
c aes.CTR
reseedCounter uint64
}