c# - HMAC with custom HashAlgorithm -


there built in hmac's (hmacsha1 - hmacsha512 ...). possible create hmac custom hashalgorithm class?

i tried hmac.create("location") threw nullreferenceexception

could there constructor new hmac(hashalgorithm)?

this code hashalgorithm (fnv1 hash):

public class fnv1_32 : hashalgorithm {     private const uint prime = 0x01000193;     private const uint offsetbasis = 0x811c9dc5;     private uint _hash;      public fnv1_32()     {         this.initialize();         this.hashsizevalue = 32;     }      public override void initialize()     {         this._hash = offsetbasis;     }      protected override void hashcore(byte[] array, int ibstart, int cbsize)     {         (var = ibstart; < cbsize; i++)         {             this._hash *= prime;             this._hash ^= array[i];         }     }      protected override byte[] hashfinal()     {         return bitconverter.getbytes(this._hash);     } }

in .net framework can accomplish via like

public class hmacfnv1_32 : hmac {     private const string fnv1cryptoconfigid = "fnv1_32";      static hmacfnv1_32()     {         cryptoconfig.addalgorithm(typeof(fnv1_32), fnv1cryptoconfigid);     }      public hmacfnv1_32(byte[] key)     {         hashname = fnv1cryptoconfigid;         hashsizevalue = 32;         key = key;     } }

on .net core hmac implementation has been removed, of builtin hmac classes call system cryptography libraries perform hmac calculations. you'd need write hmac use custom digest .net core.


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