Introduce extra delay before closing unauthenticated sessions To make it harder for attackers, introduce a delay to keep an unauthenticated session open a bit longer, thus blocking a connection slot until after the delay. Without this, while there is a limit on the amount of attempts an attacker can make at the same time (MAX_UNAUTH_PER_IP), the time taken by dropbear to handle one attempt is still short and thus for each of the allowed parallel attempts many attempts can be chained one after the other. The attempt rate is then: "MAX_UNAUTH_PER_IP / <process time of one attempt>". With the delay, this rate becomes: "MAX_UNAUTH_PER_IP / UNAUTH_CLOSE_DELAY".

#include "tommath_private.h"
#ifdef BN_MP_CMP_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */

/* compare two ints (signed)*/
mp_ord mp_cmp(const mp_int *a, const mp_int *b)
{
   /* compare based on sign */
   if (a->sign != b->sign) {
      if (a->sign == MP_NEG) {
         return MP_LT;
      } else {
         return MP_GT;
      }
   }

   /* compare digits */
   if (a->sign == MP_NEG) {
      /* if negative compare opposite direction */
      return mp_cmp_mag(b, a);
   } else {
      return mp_cmp_mag(a, b);
   }
}
#endif