Mercurial > dropbear
view libtomcrypt/src/misc/crypt/crypt_constants.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 | e9dba7abd939 |
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 crypt_constants.c Make various constants available to dynamic languages like Python - Larry Bugbee, February 2013 LB - Dec 2013 - revised to include compiler define options LB - Mar 2014 - added endianness and word size */ typedef struct { const char *name; const int value; } crypt_constant; #define _C_STRINGIFY(s) { #s, s } static const crypt_constant _crypt_constants[] = { _C_STRINGIFY(CRYPT_OK), _C_STRINGIFY(CRYPT_ERROR), _C_STRINGIFY(CRYPT_NOP), _C_STRINGIFY(CRYPT_INVALID_KEYSIZE), _C_STRINGIFY(CRYPT_INVALID_ROUNDS), _C_STRINGIFY(CRYPT_FAIL_TESTVECTOR), _C_STRINGIFY(CRYPT_BUFFER_OVERFLOW), _C_STRINGIFY(CRYPT_INVALID_PACKET), _C_STRINGIFY(CRYPT_INVALID_PRNGSIZE), _C_STRINGIFY(CRYPT_ERROR_READPRNG), _C_STRINGIFY(CRYPT_INVALID_CIPHER), _C_STRINGIFY(CRYPT_INVALID_HASH), _C_STRINGIFY(CRYPT_INVALID_PRNG), _C_STRINGIFY(CRYPT_MEM), _C_STRINGIFY(CRYPT_PK_TYPE_MISMATCH), _C_STRINGIFY(CRYPT_PK_NOT_PRIVATE), _C_STRINGIFY(CRYPT_INVALID_ARG), _C_STRINGIFY(CRYPT_FILE_NOTFOUND), _C_STRINGIFY(CRYPT_PK_INVALID_TYPE), _C_STRINGIFY(CRYPT_OVERFLOW), _C_STRINGIFY(CRYPT_UNUSED1), _C_STRINGIFY(CRYPT_INPUT_TOO_LONG), _C_STRINGIFY(CRYPT_PK_INVALID_SIZE), _C_STRINGIFY(CRYPT_INVALID_PRIME_SIZE), _C_STRINGIFY(CRYPT_PK_INVALID_PADDING), _C_STRINGIFY(CRYPT_HASH_OVERFLOW), _C_STRINGIFY(PK_PUBLIC), _C_STRINGIFY(PK_PRIVATE), _C_STRINGIFY(LTC_ENCRYPT), _C_STRINGIFY(LTC_DECRYPT), #ifdef LTC_PKCS_1 {"LTC_PKCS_1", 1}, /* Block types */ _C_STRINGIFY(LTC_PKCS_1_EMSA), _C_STRINGIFY(LTC_PKCS_1_EME), /* Padding types */ _C_STRINGIFY(LTC_PKCS_1_V1_5), _C_STRINGIFY(LTC_PKCS_1_OAEP), _C_STRINGIFY(LTC_PKCS_1_PSS), _C_STRINGIFY(LTC_PKCS_1_V1_5_NA1), #else {"LTC_PKCS_1", 0}, #endif #ifdef LTC_MRSA {"LTC_MRSA", 1}, #else {"LTC_MRSA", 0}, #endif #ifdef LTC_MKAT {"LTC_MKAT", 1}, _C_STRINGIFY(MIN_KAT_SIZE), _C_STRINGIFY(MAX_KAT_SIZE), #else {"LTC_MKAT", 0}, #endif #ifdef LTC_MECC {"LTC_MECC", 1}, _C_STRINGIFY(ECC_BUF_SIZE), _C_STRINGIFY(ECC_MAXSIZE), #else {"LTC_MECC", 0}, #endif #ifdef LTC_MDSA {"LTC_MDSA", 1}, _C_STRINGIFY(LTC_MDSA_DELTA), _C_STRINGIFY(LTC_MDSA_MAX_GROUP), #else {"LTC_MDSA", 0}, #endif #ifdef LTC_MILLER_RABIN_REPS _C_STRINGIFY(LTC_MILLER_RABIN_REPS), #endif #ifdef LTC_DER /* DER handling */ {"LTC_DER", 1}, _C_STRINGIFY(LTC_ASN1_EOL), _C_STRINGIFY(LTC_ASN1_BOOLEAN), _C_STRINGIFY(LTC_ASN1_INTEGER), _C_STRINGIFY(LTC_ASN1_SHORT_INTEGER), _C_STRINGIFY(LTC_ASN1_BIT_STRING), _C_STRINGIFY(LTC_ASN1_OCTET_STRING), _C_STRINGIFY(LTC_ASN1_NULL), _C_STRINGIFY(LTC_ASN1_OBJECT_IDENTIFIER), _C_STRINGIFY(LTC_ASN1_IA5_STRING), _C_STRINGIFY(LTC_ASN1_PRINTABLE_STRING), _C_STRINGIFY(LTC_ASN1_UTF8_STRING), _C_STRINGIFY(LTC_ASN1_UTCTIME), _C_STRINGIFY(LTC_ASN1_CHOICE), _C_STRINGIFY(LTC_ASN1_SEQUENCE), _C_STRINGIFY(LTC_ASN1_SET), _C_STRINGIFY(LTC_ASN1_SETOF), _C_STRINGIFY(LTC_ASN1_RAW_BIT_STRING), _C_STRINGIFY(LTC_ASN1_TELETEX_STRING), _C_STRINGIFY(LTC_ASN1_CONSTRUCTED), _C_STRINGIFY(LTC_ASN1_CONTEXT_SPECIFIC), _C_STRINGIFY(LTC_ASN1_GENERALIZEDTIME), _C_STRINGIFY(LTC_DER_MAX_RECURSION), #else {"LTC_DER", 0}, #endif #ifdef LTC_CTR_MODE {"LTC_CTR_MODE", 1}, _C_STRINGIFY(CTR_COUNTER_LITTLE_ENDIAN), _C_STRINGIFY(CTR_COUNTER_BIG_ENDIAN), _C_STRINGIFY(LTC_CTR_RFC3686), #else {"LTC_CTR_MODE", 0}, #endif #ifdef LTC_GCM_MODE _C_STRINGIFY(LTC_GCM_MODE_IV), _C_STRINGIFY(LTC_GCM_MODE_AAD), _C_STRINGIFY(LTC_GCM_MODE_TEXT), #endif _C_STRINGIFY(LTC_MP_LT), _C_STRINGIFY(LTC_MP_EQ), _C_STRINGIFY(LTC_MP_GT), _C_STRINGIFY(LTC_MP_NO), _C_STRINGIFY(LTC_MP_YES), _C_STRINGIFY(MAXBLOCKSIZE), _C_STRINGIFY(TAB_SIZE), _C_STRINGIFY(ARGTYPE), #ifdef LTM_DESC {"LTM_DESC", 1}, #else {"LTM_DESC", 0}, #endif #ifdef TFM_DESC {"TFM_DESC", 1}, #else {"TFM_DESC", 0}, #endif #ifdef GMP_DESC {"GMP_DESC", 1}, #else {"GMP_DESC", 0}, #endif #ifdef LTC_FAST {"LTC_FAST", 1}, #else {"LTC_FAST", 0}, #endif #ifdef LTC_NO_FILE {"LTC_NO_FILE", 1}, #else {"LTC_NO_FILE", 0}, #endif #ifdef ENDIAN_LITTLE {"ENDIAN_LITTLE", 1}, #else {"ENDIAN_LITTLE", 0}, #endif #ifdef ENDIAN_BIG {"ENDIAN_BIG", 1}, #else {"ENDIAN_BIG", 0}, #endif #ifdef ENDIAN_32BITWORD {"ENDIAN_32BITWORD", 1}, #else {"ENDIAN_32BITWORD", 0}, #endif #ifdef ENDIAN_64BITWORD {"ENDIAN_64BITWORD", 1}, #else {"ENDIAN_64BITWORD", 0}, #endif #ifdef ENDIAN_NEUTRAL {"ENDIAN_NEUTRAL", 1}, #else {"ENDIAN_NEUTRAL", 0}, #endif }; /* crypt_get_constant() * valueout will be the value of the named constant * return -1 if named item not found */ int crypt_get_constant(const char* namein, int *valueout) { int i; int _crypt_constants_len = sizeof(_crypt_constants) / sizeof(_crypt_constants[0]); for (i=0; i<_crypt_constants_len; i++) { if (XSTRCMP(_crypt_constants[i].name, namein) == 0) { *valueout = _crypt_constants[i].value; return 0; } } return 1; } /* crypt_list_all_constants() * if names_list is NULL, names_list_size will be the minimum * number of bytes needed to receive the complete names_list * if names_list is NOT NULL, names_list must be the addr of * sufficient memory allocated into which the names_list * is to be written. Also, the value in names_list_size * sets the upper bound of the number of characters to be * written. * a -1 return value signifies insufficient space made available */ int crypt_list_all_constants(char *names_list, unsigned int *names_list_size) { int i; unsigned int total_len = 0; char *ptr; int number_len; int count = sizeof(_crypt_constants) / sizeof(_crypt_constants[0]); /* calculate amount of memory required for the list */ for (i=0; i<count; i++) { number_len = snprintf(NULL, 0, "%s,%d\n", _crypt_constants[i].name, _crypt_constants[i].value); if (number_len < 0) return -1; total_len += number_len; } if (names_list == NULL) { *names_list_size = total_len; } else { if (total_len > *names_list_size) { return -1; } /* build the names list */ ptr = names_list; for (i=0; i<count; i++) { number_len = snprintf(ptr, total_len, "%s,%d\n", _crypt_constants[i].name, _crypt_constants[i].value); if (number_len < 0) return -1; if ((unsigned int)number_len > total_len) return -1; total_len -= number_len; ptr += number_len; } /* to remove the trailing new-line */ ptr -= 1; *ptr = 0; } return 0; } /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */