Mercurial > dropbear
view dbhelpers.h @ 1790:42745af83b7d
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".
author | Thomas De Schampheleire <thomas.de_schampheleire@nokia.com> |
---|---|
date | Wed, 15 Feb 2017 13:53:04 +0100 |
parents | d68d61e7056a |
children |
line wrap: on
line source
#ifndef DROPBEAR_DBHELPERS_H_ #define DROPBEAR_DBHELPERS_H_ /* This header defines some things that are also used by libtomcrypt/math. We avoid including normal include.h since that can result in conflicting definitions - only include config.h */ #include "config.h" #ifdef __GNUC__ #define ATTRIB_PRINTF(fmt,args) __attribute__((format(printf, fmt, args))) #define ATTRIB_NORETURN __attribute__((noreturn)) #define ATTRIB_SENTINEL __attribute__((sentinel)) #else #define ATTRIB_PRINTF(fmt,args) #define ATTRIB_NORETURN #define ATTRIB_SENTINEL #endif void m_burn(void* data, unsigned int len); #endif /* DROPBEAR_DBHELPERS_H_ */