From 0879909b08d2c9d95fcd544e5ad9b8598b856df4 Mon Sep 17 00:00:00 2001 From: Christian Pointner Date: Sun, 28 Dec 2008 18:38:42 +0000 Subject: added cipher (net tested yet) --- src/cipher.c | 175 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 175 insertions(+) create mode 100644 src/cipher.c (limited to 'src/cipher.c') diff --git a/src/cipher.c b/src/cipher.c new file mode 100644 index 0000000..02960e4 --- /dev/null +++ b/src/cipher.c @@ -0,0 +1,175 @@ +/* + * ľAnytun + * + * ľAnytun is a tiny implementation of SATP. Unlike Anytun which is a full + * featured implementation ľAnytun has no support for multiple connections + * or synchronisation. It is a small single threaded implementation intended + * to act as a client on small platforms. + * The secure anycast tunneling protocol (satp) defines a protocol used + * for communication between any combination of unicast and anycast + * tunnel endpoints. It has less protocol overhead than IPSec in Tunnel + * mode and allows tunneling of every ETHER TYPE protocol (e.g. + * ethernet, ip, arp ...). satp directly includes cryptography and + * message authentication based on the methodes used by SRTP. It is + * intended to deliver a generic, scaleable and secure solution for + * tunneling and relaying of packets of any protocol. + * + * + * Copyright (C) 2007-2008 Christian Pointner + * + * This file is part of ľAnytun. + * + * ľAnytun is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 3 as + * published by the Free Software Foundation. + * + * ľAnytun is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with ľAnytun. If not, see . + */ + +#include "datatypes.h" + +#include "plain_packet.h" +#include "encrypted_packet.h" + +#include "cipher.h" + +#include "log.h" + +#include +#include + +void cipher_init(cipher_t** c, const char* type) +{ + if(!c) + return; + + *c = malloc(sizeof(cipher_t)); + if(!*c) + return; + + (*c)->type_ = unknown; + if(!strcmp(type, "null")) + (*c)->type_ = null; + else if(!strcmp(type, "aes-ctr")) + (*c)->type_ = aes_ctr; + else { + log_printf(ERR, "unknown cipher type"); + } + + (*c)->key_.buf_ = NULL; + (*c)->key_.length_ = 0; + + (*c)->salt_.buf_ = NULL; + (*c)->salt_.length_ = 0; +} + +void cipher_set_key(cipher_t* c, u_int8_t* key, u_int32_t len) +{ + if(!c) + return; + if(c->type_ == null) + return; + + if(c->key_.buf_) + free(c->key_.buf_); + c->key_.buf_ = malloc(len); + if(!c->key_.buf_) + return; + memcpy(c->key_.buf_, key, len); + c->key_.length_ = len; +} + +void cipher_set_salt(cipher_t* c, u_int8_t* salt, u_int32_t len) +{ + if(!c) + return; + if(c->type_ == null) + return; + + if(c->salt_.buf_) + free(c->salt_.buf_); + c->salt_.buf_ = malloc(len); + if(!c->salt_.buf_) + return; + memcpy(c->salt_.buf_, salt, len); + c->salt_.length_ = len; +} + +void cipher_close(cipher_t** c) +{ + if(!c || !(*c)) + return; + + if((*c)->key_.buf_) + free((*c)->key_.buf_); + if((*c)->salt_.buf_) + free((*c)->salt_.buf_); + + free(*c); + *c = NULL; +} + +void cipher_encrypt(cipher_t* c, plain_packet_t* in, encrypted_packet_t* out, seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux) +{ + if(!c) + return; + + u_int32_t len; + if(c->type_ = null) + len = cipher_null_encrypt(plain_packet_get_packet(in), plain_packet_get_length(in), + encrypted_packet_get_payload(out), encrypted_packet_get_payload_length(out)); + else if(c->type_ = aes_ctr) + len = cipher_aesctr_encrypt(plain_packet_get_packet(in), plain_packet_get_length(in), + encrypted_packet_get_payload(out), encrypted_packet_get_payload_length(out), + seq_nr, sender_id, mux); + else { + log_printf(ERR, "unknown cipher type"); + return; + } + + encrypted_packet_set_sender_id(out, sender_id); + encrypted_packet_set_seq_nr(out, seq_nr); + encrypted_packet_set_mux(out, mux); + + encrypted_packet_set_payload_length(out, len); +} + +void cipher_decrypt(cipher_t* c, encrypted_packet_t* in, plain_packet_t* out) +{ + if(!c) + return; + + u_int32_t len; + if(c->type_ = null) + len = cipher_null_decrypt(encrypted_packet_get_payload(in), encrypted_packet_get_payload_length(in), + plain_packet_get_packet(out), plain_packet_get_length(out)); + else if(c->type_ = aes_ctr) + len = cipher_aesctr_decrypt(encrypted_packet_get_payload(in), encrypted_packet_get_payload_length(in), + plain_packet_get_packet(out), plain_packet_get_length(out), + encrypted_packet_get_seq_nr(in), encrypted_packet_get_sender_id(in), + encrypted_packet_get_mux(in)); + else { + log_printf(ERR, "unknown cipher type"); + return; + } + + plain_packet_set_length(out, len); +} + +u_int32_t cipher_null_encrypt(u_int8_t* in, u_int32_t ilen, u_int8_t* out, u_int32_t olen) +{ + memcpy(out, in, (ilen < olen) ? ilen : olen); + return (ilen < olen) ? ilen : olen; +} + +u_int32_t cipher_null_decrypt(u_int8_t* in, u_int32_t ilen, u_int8_t* out, u_int32_t olen) +{ + memcpy(out, in, (ilen < olen) ? ilen : olen); + return (ilen < olen) ? ilen : olen; +} -- cgit v1.2.3