Mercurial > dropbear
view libtomcrypt/tests/base64_test.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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line source
/* 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_test.h> #if defined(LTC_BASE64) || defined(LTC_BASE64_URL) int base64_test(void) { unsigned char in[64], out[256], tmp[64]; unsigned long x, l1, l2, slen1; const unsigned char special_case[] = { 0xbe, 0xe8, 0x92, 0x3c, 0xa2, 0x25, 0xf0, 0xf8, 0x91, 0xe4, 0xef, 0xab, 0x0b, 0x8c, 0xfd, 0xff, 0x14, 0xd0, 0x29, 0x9d, 0x00 }; #if defined(LTC_BASE64) /* TEST CASES SOURCE: Network Working Group S. Josefsson Request for Comments: 4648 SJD Obsoletes: 3548 October 2006 Category: Standards Track */ const struct { const char* s; const char* b64; } cases[] = { {"", "" }, {"f", "Zg==" }, {"fo", "Zm8=" }, {"foo", "Zm9v" }, {"foob", "Zm9vYg==" }, {"fooba", "Zm9vYmE=" }, {"foobar", "Zm9vYmFy"}, {(char*)special_case,"vuiSPKIl8PiR5O+rC4z9/xTQKZ0="} }; #endif #ifdef LTC_BASE64_URL const struct { const char* s; int is_strict; } url_cases[] = { {"vuiSPKIl8PiR5O-rC4z9_xTQKZ0", 0}, {"vuiSPKIl8PiR5O-rC4z9_xTQKZ0=", 1}, {"vuiS*PKIl8P*iR5O-rC4*z9_xTQKZ0", 0}, {"vuiS*PKIl8P*iR5O-rC4*z9_xTQKZ0=", 0}, {"vuiS*PKIl8P*iR5O-rC4*z9_xTQKZ0==", 0}, {"vuiS*PKIl8P*iR5O-rC4*z9_xTQKZ0===", 0}, {"vuiS*PKIl8P*iR5O-rC4*z9_xTQKZ0====", 0}, {"vuiS*=PKIl8P*iR5O-rC4*z9_xTQKZ0=", 0}, {"vuiS*==PKIl8P*iR5O-rC4*z9_xTQKZ0=", 0}, {"vuiS*===PKIl8P*iR5O-rC4*z9_xTQKZ0=", 0}, }; for (x = 0; x < sizeof(url_cases)/sizeof(url_cases[0]); ++x) { slen1 = strlen(url_cases[x].s); l1 = sizeof(out); if(url_cases[x].is_strict) DO(base64url_strict_decode((unsigned char*)url_cases[x].s, slen1, out, &l1)); else DO(base64url_decode((unsigned char*)url_cases[x].s, slen1, out, &l1)); if (compare_testvector(out, l1, special_case, sizeof(special_case) - 1, "base64url decode", x)) { return 1; } if(x < 2) { l2 = sizeof(tmp); if(x == 0) DO(base64url_encode(out, l1, tmp, &l2)); else DO(base64url_strict_encode(out, l1, tmp, &l2)); if (compare_testvector(tmp, l2, url_cases[x].s, strlen(url_cases[x].s), "base64url encode", x)) { return 1; } } } DO(base64url_strict_decode((unsigned char*)url_cases[4].s, slen1, out, &l1) == CRYPT_INVALID_PACKET ? CRYPT_OK : CRYPT_INVALID_PACKET); #endif #if defined(LTC_BASE64) for (x = 0; x < sizeof(cases)/sizeof(cases[0]); ++x) { memset(out, 0, sizeof(out)); memset(tmp, 0, sizeof(tmp)); slen1 = strlen(cases[x].s); l1 = sizeof(out); DO(base64_encode((unsigned char*)cases[x].s, slen1, out, &l1)); l2 = sizeof(tmp); DO(base64_strict_decode(out, l1, tmp, &l2)); if (compare_testvector(out, l1, cases[x].b64, strlen(cases[x].b64), "base64 encode", x) || compare_testvector(tmp, l2, cases[x].s, slen1, "base64 decode", x)) { return 1; } } for (x = 0; x < 64; x++) { yarrow_read(in, x, &yarrow_prng); l1 = sizeof(out); DO(base64_encode(in, x, out, &l1)); l2 = sizeof(tmp); DO(base64_decode(out, l1, tmp, &l2)); if (compare_testvector(tmp, x, in, x, "random base64", x)) { return 1; } } x--; memmove(&out[11], &out[10], l1 - 10); out[10] = '='; l1++; l2 = sizeof(tmp); DO(base64_decode(out, l1, tmp, &l2)); if (compare_testvector(tmp, l2, in, l2, "relaxed base64 decoding", -1)) { print_hex("input ", out, l1); return 1; } l2 = sizeof(tmp); DO(base64_strict_decode(out, l1, tmp, &l2) == CRYPT_INVALID_PACKET ? CRYPT_OK : CRYPT_INVALID_PACKET); #endif return 0; } #endif /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */