peer.c

00001 /* dtls -- a very basic DTLS implementation
00002  *
00003  * Copyright (C) 2011--2013 Olaf Bergmann <bergmann@tzi.org>
00004  *
00005  * Permission is hereby granted, free of charge, to any person
00006  * obtaining a copy of this software and associated documentation
00007  * files (the "Software"), to deal in the Software without
00008  * restriction, including without limitation the rights to use, copy,
00009  * modify, merge, publish, distribute, sublicense, and/or sell copies
00010  * of the Software, and to permit persons to whom the Software is
00011  * furnished to do so, subject to the following conditions:
00012  *
00013  * The above copyright notice and this permission notice shall be
00014  * included in all copies or substantial portions of the Software.
00015  *
00016  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
00017  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
00018  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00019  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
00020  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
00021  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
00022  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
00023  * SOFTWARE.
00024  */
00025  
00026 #define __DEBUG__ 4
00027 
00028 #ifndef __MODULE__
00029 #define __MODULE__ "peer.c"
00030 #endif
00031 
00032 #include "peer.h"
00033 #include "debug.h"
00034 #include "dbg.h"
00035 
00036 #ifndef NDEBUG
00037 #include <stdio.h>
00038 
00039 extern size_t dsrv_print_addr(const session_t *addr, unsigned char *buf, 
00040                   size_t len);
00041 #endif /* NDEBUG */
00042 
00043 #ifndef WITH_CONTIKI
00044 void peer_init()
00045 {
00046 }
00047 
00048 static inline dtls_peer_t *
00049 dtls_malloc_peer() {
00050   return (dtls_peer_t *)malloc(sizeof(dtls_peer_t));
00051 }
00052 
00053 void
00054 dtls_free_peer(dtls_peer_t *peer) {
00055   free(peer);
00056 }
00057 #else /* WITH_CONTIKI */
00058 PROCESS(dtls_retransmit_process, "DTLS retransmit process");
00059 
00060 #include "memb.h"
00061 MEMB(peer_storage, dtls_peer_t, DTLS_PEER_MAX);
00062 
00063 void
00064 peer_init() {
00065   memb_init(&peer_storage);
00066 }
00067 
00068 static inline dtls_peer_t *
00069 dtls_malloc_peer() {
00070   return memb_alloc(&peer_storage);
00071 }
00072 
00073 void
00074 dtls_free_peer(dtls_peer_t *peer) {
00075   memb_free(&peer_storage, peer);
00076 }
00077 #endif /* WITH_CONTIKI */
00078 
00079 dtls_peer_t *
00080 dtls_new_peer(const session_t *session) {
00081   DBG("Entered dtls_new_peer");
00082   dtls_peer_t *peer;
00083 
00084   peer = dtls_malloc_peer();
00085   if (peer) {
00086     memset(peer, 0, sizeof(dtls_peer_t));
00087     memcpy(&peer->session, session, sizeof(session_t));
00088 
00089 #ifndef NDEBUG
00090     if (dtls_get_log_level() >= LOG_DEBUG) {
00091       unsigned char addrbuf[72];
00092       dsrv_print_addr(session, addrbuf, sizeof(addrbuf));
00093       DBG("Created peer for: \"%s\"", addrbuf);
00094     }
00095 #endif
00096     /* initially allow the NULL cipher */
00097     CURRENT_CONFIG(peer)->cipher = TLS_NULL_WITH_NULL_NULL;
00098 
00099     /* initialize the handshake hash wrt. the hard-coded DTLS version */
00100     DBG("DTLSv12: initialize HASH_SHA256");
00101     /* TLS 1.2:  PRF(secret, label, seed) = P_<hash>(secret, label + seed) */
00102     /* FIXME: we use the default SHA256 here, might need to support other 
00103               hash functions as well */
00104     dtls_hash_init(&peer->hs_state.hs_hash);
00105   }
00106     DBG("New peer created @ %u",peer);
00107 
00108   return peer;
00109 }
00110