Mercurial > dropbear
view libtomcrypt/src/pk/pkcs1/pkcs_1_os2ip.c @ 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 | 6dba84798cd5 |
children |
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/* LibTomCrypt, modular cryptographic library -- Tom St Denis * * LibTomCrypt is a library that provides various cryptographic * algorithms in a highly modular and flexible manner. * * The library is free for all purposes without any express * guarantee it works. */ #include "tomcrypt.h" /** @file pkcs_1_os2ip.c Octet to Integer OS2IP, Tom St Denis */ #ifdef LTC_PKCS_1 /** Read a binary string into an mp_int @param n [out] The mp_int destination @param in The binary string to read @param inlen The length of the binary string @return CRYPT_OK if successful */ int pkcs_1_os2ip(void *n, unsigned char *in, unsigned long inlen) { return mp_read_unsigned_bin(n, in, inlen); } #endif /* LTC_PKCS_1 */ /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */