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".

#ifndef DBMALLOC_H_
#define DBMALLOC_H_

#include "stdint.h"
#include "stdlib.h"
#include "options.h"

void * m_malloc(size_t size);
void * m_calloc(size_t nmemb, size_t size);
void * m_strdup(const char * str);
void * m_realloc(void* ptr, size_t size);

#if DROPBEAR_TRACKING_MALLOC
void m_free_direct(void* ptr);
void m_malloc_set_epoch(unsigned int epoch);
void m_malloc_free_epoch(unsigned int epoch, int dofree);

#else
/* plain wrapper */
#define m_free_direct free

#endif

#define m_free(X) do {m_free_direct(X); (X) = NULL;} while (0)


#endif /* DBMALLOC_H_ */