Mercurial > dropbear
view libtommath/tommath_superclass.h @ 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 | 1051e4eea25a |
| children |
line wrap: on
line source
/* LibTomMath, multiple-precision integer library -- Tom St Denis */ /* SPDX-License-Identifier: Unlicense */ /* super class file for PK algos */ /* default ... include all MPI */ #ifndef LTM_NOTHING #define LTM_ALL #endif /* RSA only (does not support DH/DSA/ECC) */ /* #define SC_RSA_1 */ /* #define SC_RSA_1_WITH_TESTS */ /* For reference.... On an Athlon64 optimizing for speed... LTM's mpi.o with all functions [striped] is 142KiB in size. */ #ifdef SC_RSA_1_WITH_TESTS # define BN_MP_ERROR_TO_STRING_C # define BN_MP_FREAD_C # define BN_MP_FWRITE_C # define BN_MP_INCR_C # define BN_MP_ISEVEN_C # define BN_MP_ISODD_C # define BN_MP_NEG_C # define BN_MP_PRIME_FROBENIUS_UNDERWOOD_C # define BN_MP_RADIX_SIZE_C # define BN_MP_RAND_C # define BN_MP_REDUCE_C # define BN_MP_REDUCE_2K_L_C # define BN_MP_FROM_SBIN_C # define BN_MP_ROOT_U32_C # define BN_MP_SET_L_C # define BN_MP_SET_UL_C # define BN_MP_SBIN_SIZE_C # define BN_MP_TO_RADIX_C # define BN_MP_TO_SBIN_C # define BN_S_MP_RAND_JENKINS_C # define BN_S_MP_RAND_PLATFORM_C #endif /* Works for RSA only, mpi.o is 68KiB */ #if defined(SC_RSA_1) || defined (SC_RSA_1_WITH_TESTS) # define BN_CUTOFFS_C # define BN_MP_ADDMOD_C # define BN_MP_CLEAR_MULTI_C # define BN_MP_EXPTMOD_C # define BN_MP_GCD_C # define BN_MP_INIT_MULTI_C # define BN_MP_INVMOD_C # define BN_MP_LCM_C # define BN_MP_MOD_C # define BN_MP_MOD_D_C # define BN_MP_MULMOD_C # define BN_MP_PRIME_IS_PRIME_C # define BN_MP_PRIME_RABIN_MILLER_TRIALS_C # define BN_MP_PRIME_RAND_C # define BN_MP_RADIX_SMAP_C # define BN_MP_SET_INT_C # define BN_MP_SHRINK_C # define BN_MP_TO_UNSIGNED_BIN_C # define BN_MP_UNSIGNED_BIN_SIZE_C # define BN_PRIME_TAB_C # define BN_S_MP_REVERSE_C /* other modifiers */ # define BN_MP_DIV_SMALL /* Slower division, not critical */ /* here we are on the last pass so we turn things off. The functions classes are still there * but we remove them specifically from the build. This also invokes tweaks in functions * like removing support for even moduli, etc... */ # ifdef LTM_LAST # undef BN_MP_DR_IS_MODULUS_C # undef BN_MP_DR_SETUP_C # undef BN_MP_DR_REDUCE_C # undef BN_MP_DIV_3_C # undef BN_MP_REDUCE_2K_SETUP_C # undef BN_MP_REDUCE_2K_C # undef BN_MP_REDUCE_IS_2K_C # undef BN_MP_REDUCE_SETUP_C # undef BN_S_MP_BALANCE_MUL_C # undef BN_S_MP_EXPTMOD_C # undef BN_S_MP_INVMOD_FAST_C # undef BN_S_MP_KARATSUBA_MUL_C # undef BN_S_MP_KARATSUBA_SQR_C # undef BN_S_MP_MUL_HIGH_DIGS_C # undef BN_S_MP_MUL_HIGH_DIGS_FAST_C # undef BN_S_MP_TOOM_MUL_C # undef BN_S_MP_TOOM_SQR_C # ifndef SC_RSA_1_WITH_TESTS # undef BN_MP_REDUCE_C # endif /* To safely undefine these you have to make sure your RSA key won't exceed the Comba threshold * which is roughly 255 digits [7140 bits for 32-bit machines, 15300 bits for 64-bit machines] * which means roughly speaking you can handle upto 2536-bit RSA keys with these defined without * trouble. */ # undef BN_MP_MONTGOMERY_REDUCE_C # undef BN_S_MP_MUL_DIGS_C # undef BN_S_MP_SQR_C # endif #endif