Mercurial > dropbear
view libtomcrypt/tests/pkcs_1_test.c @ 1715:3974f087d9c0
Disallow leading lines before the ident for server (#102)
Per RFC4253 4.2 clients must be able to process other lines of data
before the version string, server behavior is not defined neither
with MUST/SHOULD nor with MAY.
If server process up to 50 lines too - it may cause too long hanging
session with invalid/evil client that consume host resources and
potentially may lead to DDoS on poor embedded boxes.
Let's require first line from client to be version string and fail
early if it's not - matches both RFC and real OpenSSH behavior.
author | Vladislav Grishenko <themiron@users.noreply.github.com> |
---|---|
date | Mon, 15 Jun 2020 18:22:18 +0500 |
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_test.h> #ifdef LTC_PKCS_1 #ifdef LTC_TEST_REAL_RAND #define LTC_TEST_RAND_SEED time(NULL) #else #define LTC_TEST_RAND_SEED 23 #endif int pkcs_1_test(void) { unsigned char buf[3][128]; int res1, res2, res3, prng_idx, hash_idx; unsigned long x, y, l1, l2, l3, i1, i2, lparamlen, saltlen, modlen; static const unsigned char lparam[] = { 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16 }; /* get hash/prng */ hash_idx = find_hash("sha1"); prng_idx = find_prng("yarrow"); if (hash_idx == -1 || prng_idx == -1) { fprintf(stderr, "pkcs_1 tests require sha1/yarrow"); return 1; } srand(LTC_TEST_RAND_SEED); /* do many tests */ for (x = 0; x < 100; x++) { zeromem(buf, sizeof(buf)); /* make a dummy message (of random length) */ l3 = (rand() & 31) + 8; for (y = 0; y < l3; y++) buf[0][y] = rand() & 255; /* pick a random lparam len [0..16] */ lparamlen = abs(rand()) % 17; /* pick a random saltlen 0..16 */ saltlen = abs(rand()) % 17; /* PKCS #1 v2.0 supports modlens not multiple of 8 */ modlen = 800 + (abs(rand()) % 224); /* encode it */ l1 = sizeof(buf[1]); DO(pkcs_1_oaep_encode(buf[0], l3, lparam, lparamlen, modlen, &yarrow_prng, prng_idx, hash_idx, buf[1], &l1)); /* decode it */ l2 = sizeof(buf[2]); DO(pkcs_1_oaep_decode(buf[1], l1, lparam, lparamlen, modlen, hash_idx, buf[2], &l2, &res1)); if (res1 != 1 || l2 != l3 || memcmp(buf[2], buf[0], l3) != 0) { fprintf(stderr, "Outsize == %lu, should have been %lu, res1 = %d, lparamlen = %lu, msg contents follow.\n", l2, l3, res1, lparamlen); fprintf(stderr, "ORIGINAL:\n"); for (x = 0; x < l3; x++) { fprintf(stderr, "%02x ", buf[0][x]); } fprintf(stderr, "\nRESULT:\n"); for (x = 0; x < l2; x++) { fprintf(stderr, "%02x ", buf[2][x]); } fprintf(stderr, "\n\n"); return 1; } /* test PSS */ l1 = sizeof(buf[1]); DO(pkcs_1_pss_encode(buf[0], l3, saltlen, &yarrow_prng, prng_idx, hash_idx, modlen, buf[1], &l1)); DO(pkcs_1_pss_decode(buf[0], l3, buf[1], l1, saltlen, hash_idx, modlen, &res1)); buf[0][i1 = abs(rand()) % l3] ^= 1; DO(pkcs_1_pss_decode(buf[0], l3, buf[1], l1, saltlen, hash_idx, modlen, &res2)); buf[0][i1] ^= 1; buf[1][i2 = abs(rand()) % (l1 - 1)] ^= 1; pkcs_1_pss_decode(buf[0], l3, buf[1], l1, saltlen, hash_idx, modlen, &res3); if (!(res1 == 1 && res2 == 0 && res3 == 0)) { fprintf(stderr, "PSS failed: %d, %d, %d, %lu, %lu\n", res1, res2, res3, l3, saltlen); return 1; } } return 0; } #else int pkcs_1_test(void) { return CRYPT_NOP; } #endif /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */