Mercurial > dropbear
view libtomcrypt/src/pk/dsa/dsa_export.c @ 994:5c5ade336926
Prefer stronger algorithms in algorithm negotiation.
Prefer diffie-hellman-group14-sha1 (2048 bit) over
diffie-hellman-group1-sha1 (1024 bit).
Due to meet-in-the-middle attacks the effective key length of
three key 3DES is 112 bits. AES is stronger and faster then 3DES.
Prefer to delay the start of compression until after authentication
has completed. This avoids exposing compression code to attacks
from unauthenticated users.
(github pull request #9)
author | Fedor Brunner <fedor.brunner@azet.sk> |
---|---|
date | Fri, 23 Jan 2015 23:00:25 +0800 |
parents | 0cbe8f6dbf9e |
children | f849a5ca2efc |
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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. * * Tom St Denis, [email protected], http://libtomcrypt.com */ #include "tomcrypt.h" /** @file dsa_export.c DSA implementation, export key, Tom St Denis */ #ifdef MDSA /** Export a DSA key to a binary packet @param out [out] Where to store the packet @param outlen [in/out] The max size and resulting size of the packet @param type The type of key to export (PK_PRIVATE or PK_PUBLIC) @param key The key to export @return CRYPT_OK if successful */ int dsa_export(unsigned char *out, unsigned long *outlen, int type, dsa_key *key) { unsigned char flags[1]; LTC_ARGCHK(out != NULL); LTC_ARGCHK(outlen != NULL); LTC_ARGCHK(key != NULL); /* can we store the static header? */ if (type == PK_PRIVATE && key->type != PK_PRIVATE) { return CRYPT_PK_TYPE_MISMATCH; } if (type != PK_PUBLIC && type != PK_PRIVATE) { return CRYPT_INVALID_ARG; } flags[0] = (type != PK_PUBLIC) ? 1 : 0; if (type == PK_PRIVATE) { return der_encode_sequence_multi(out, outlen, LTC_ASN1_BIT_STRING, 1UL, flags, LTC_ASN1_INTEGER, 1UL, key->g, LTC_ASN1_INTEGER, 1UL, key->p, LTC_ASN1_INTEGER, 1UL, key->q, LTC_ASN1_INTEGER, 1UL, key->y, LTC_ASN1_INTEGER, 1UL, key->x, LTC_ASN1_EOL, 0UL, NULL); } else { return der_encode_sequence_multi(out, outlen, LTC_ASN1_BIT_STRING, 1UL, flags, LTC_ASN1_INTEGER, 1UL, key->g, LTC_ASN1_INTEGER, 1UL, key->p, LTC_ASN1_INTEGER, 1UL, key->q, LTC_ASN1_INTEGER, 1UL, key->y, LTC_ASN1_EOL, 0UL, NULL); } } #endif /* $Source: /cvs/libtom/libtomcrypt/src/pk/dsa/dsa_export.c,v $ */ /* $Revision: 1.8 $ */ /* $Date: 2006/03/31 14:15:35 $ */