void KDF2()

in src/ecdh_support.c [189:208]

• 15 lines of code
• 3 McCabe index (conditional complexity)

void KDF2(int sha,const octet *z,const octet *p,int olen,octet *key)
{
    /* NOTE: the parameter olen is the length of the output k in bytes */
    char h[64];
    octet H= {0,sizeof(h),h};
    int cthreshold;
    int hlen=sha;

    OCT_empty(key);

    cthreshold=ROUNDUP(olen,hlen);

    for (int counter=1; counter<=cthreshold; counter++)
    {
        ehashit(sha,z,counter,p,&H,0);
        if (key->len+hlen>olen)  OCT_jbytes(key,H.val,olen%hlen);
        else                     OCT_joctet(key,&H);
    }

}