/* ssl/d1_lib.c */ /* * DTLS implementation written by Nagendra Modadugu * (nagendra@cs.stanford.edu) for the OpenSSL project 2005. */ /* ==================================================================== * Copyright (c) 1999-2005 The OpenSSL Project. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. All advertising materials mentioning features or use of this * software must display the following acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" * * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to * endorse or promote products derived from this software without * prior written permission. For written permission, please contact * openssl-core@OpenSSL.org. * * 5. Products derived from this software may not be called "OpenSSL" * nor may "OpenSSL" appear in their names without prior written * permission of the OpenSSL Project. * * 6. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" * * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED * OF THE POSSIBILITY OF SUCH DAMAGE. * ==================================================================== * * This product includes cryptographic software written by Eric Young * (eay@cryptsoft.com). This product includes software written by Tim * Hudson (tjh@cryptsoft.com). * */ #include <stdio.h> #define USE_SOCKETS #include <openssl/objects.h> #include "ssl_locl.h" #if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS) #include <sys/timeb.h> #endif static void get_current_time(struct timeval *t); const char dtls1_version_str[]="DTLSv1" OPENSSL_VERSION_PTEXT; int dtls1_listen(SSL *s, struct sockaddr *client); SSL3_ENC_METHOD DTLSv1_enc_data={ dtls1_enc, tls1_mac, tls1_setup_key_block, tls1_generate_master_secret, tls1_change_cipher_state, tls1_final_finish_mac, TLS1_FINISH_MAC_LENGTH, tls1_cert_verify_mac, TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE, TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE, tls1_alert_code, }; long dtls1_default_timeout(void) { /* 2 hours, the 24 hours mentioned in the DTLSv1 spec * is way too long for http, the cache would over fill */ return(60*60*2); } int dtls1_new(SSL *s) { DTLS1_STATE *d1; if (!ssl3_new(s)) return(0); if ((d1=OPENSSL_malloc(sizeof *d1)) == NULL) return (0); memset(d1,0, sizeof *d1); /* d1->handshake_epoch=0; */ d1->unprocessed_rcds.q=pqueue_new(); d1->processed_rcds.q=pqueue_new(); d1->buffered_messages = pqueue_new(); d1->sent_messages=pqueue_new(); d1->buffered_app_data.q=pqueue_new(); if ( s->server) { d1->cookie_len = sizeof(s->d1->cookie); } if( ! d1->unprocessed_rcds.q || ! d1->processed_rcds.q || ! d1->buffered_messages || ! d1->sent_messages || ! d1->buffered_app_data.q) { if ( d1->unprocessed_rcds.q) pqueue_free(d1->unprocessed_rcds.q); if ( d1->processed_rcds.q) pqueue_free(d1->processed_rcds.q); if ( d1->buffered_messages) pqueue_free(d1->buffered_messages); if ( d1->sent_messages) pqueue_free(d1->sent_messages); if ( d1->buffered_app_data.q) pqueue_free(d1->buffered_app_data.q); OPENSSL_free(d1); return (0); } s->d1=d1; s->method->ssl_clear(s); return(1); } void dtls1_free(SSL *s) { pitem *item = NULL; hm_fragment *frag = NULL; ssl3_free(s); while( (item = pqueue_pop(s->d1->unprocessed_rcds.q)) != NULL) { OPENSSL_free(item->data); pitem_free(item); } pqueue_free(s->d1->unprocessed_rcds.q); while( (item = pqueue_pop(s->d1->processed_rcds.q)) != NULL) { OPENSSL_free(item->data); pitem_free(item); } pqueue_free(s->d1->processed_rcds.q); while( (item = pqueue_pop(s->d1->buffered_messages)) != NULL) { frag = (hm_fragment *)item->data; OPENSSL_free(frag->fragment); OPENSSL_free(frag); pitem_free(item); } pqueue_free(s->d1->buffered_messages); while ( (item = pqueue_pop(s->d1->sent_messages)) != NULL) { frag = (hm_fragment *)item->data; OPENSSL_free(frag->fragment); OPENSSL_free(frag); pitem_free(item); } pqueue_free(s->d1->sent_messages); while ( (item = pqueue_pop(s->d1->buffered_app_data.q)) != NULL) { frag = (hm_fragment *)item->data; OPENSSL_free(frag->fragment); OPENSSL_free(frag); pitem_free(item); } pqueue_free(s->d1->buffered_app_data.q); OPENSSL_free(s->d1); } void dtls1_clear(SSL *s) { ssl3_clear(s); if (s->options & SSL_OP_CISCO_ANYCONNECT) s->version=DTLS1_BAD_VER; else s->version=DTLS1_VERSION; } long dtls1_ctrl(SSL *s, int cmd, long larg, void *parg) { int ret=0; switch (cmd) { case DTLS_CTRL_GET_TIMEOUT: if (dtls1_get_timeout(s, (struct timeval*) parg) != NULL) { ret = 1; } break; case DTLS_CTRL_HANDLE_TIMEOUT: ret = dtls1_handle_timeout(s); break; case DTLS_CTRL_LISTEN: ret = dtls1_listen(s, parg); break; default: ret = ssl3_ctrl(s, cmd, larg, parg); break; } return(ret); } /* * As it's impossible to use stream ciphers in "datagram" mode, this * simple filter is designed to disengage them in DTLS. Unfortunately * there is no universal way to identify stream SSL_CIPHER, so we have * to explicitly list their SSL_* codes. Currently RC4 is the only one * available, but if new ones emerge, they will have to be added... */ const SSL_CIPHER *dtls1_get_cipher(unsigned int u) { const SSL_CIPHER *ciph = ssl3_get_cipher(u); if (ciph != NULL) { if (ciph->algorithm_enc == SSL_RC4) return NULL; } return ciph; } void dtls1_start_timer(SSL *s) { /* If timer is not set, initialize duration with 1 second */ if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0) { s->d1->timeout_duration = 1; } /* Set timeout to current time */ get_current_time(&(s->d1->next_timeout)); /* Add duration to current time */ s->d1->next_timeout.tv_sec += s->d1->timeout_duration; BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0, &(s->d1->next_timeout)); } struct timeval* dtls1_get_timeout(SSL *s, struct timeval* timeleft) { struct timeval timenow; /* If no timeout is set, just return NULL */ if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0) { return NULL; } /* Get current time */ get_current_time(&timenow); /* If timer already expired, set remaining time to 0 */ if (s->d1->next_timeout.tv_sec < timenow.tv_sec || (s->d1->next_timeout.tv_sec == timenow.tv_sec && s->d1->next_timeout.tv_usec <= timenow.tv_usec)) { memset(timeleft, 0, sizeof(struct timeval)); return timeleft; } /* Calculate time left until timer expires */ memcpy(timeleft, &(s->d1->next_timeout), sizeof(struct timeval)); timeleft->tv_sec -= timenow.tv_sec; timeleft->tv_usec -= timenow.tv_usec; if (timeleft->tv_usec < 0) { timeleft->tv_sec--; timeleft->tv_usec += 1000000; } /* If remaining time is less than 15 ms, set it to 0 * to prevent issues because of small devergences with * socket timeouts. */ if (timeleft->tv_sec == 0 && timeleft->tv_usec < 15000) { memset(timeleft, 0, sizeof(struct timeval)); } return timeleft; } int dtls1_is_timer_expired(SSL *s) { struct timeval timeleft; /* Get time left until timeout, return false if no timer running */ if (dtls1_get_timeout(s, &timeleft) == NULL) { return 0; } /* Return false if timer is not expired yet */ if (timeleft.tv_sec > 0 || timeleft.tv_usec > 0) { return 0; } /* Timer expired, so return true */ return 1; } void dtls1_double_timeout(SSL *s) { s->d1->timeout_duration *= 2; if (s->d1->timeout_duration > 60) s->d1->timeout_duration = 60; dtls1_start_timer(s); } void dtls1_stop_timer(SSL *s) { /* Reset everything */ memset(&(s->d1->next_timeout), 0, sizeof(struct timeval)); s->d1->timeout_duration = 1; BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0, &(s->d1->next_timeout)); } int dtls1_handle_timeout(SSL *s) { DTLS1_STATE *state; /* if no timer is expired, don't do anything */ if (!dtls1_is_timer_expired(s)) { return 0; } dtls1_double_timeout(s); state = s->d1; state->timeout.num_alerts++; if ( state->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT) { /* fail the connection, enough alerts have been sent */ SSLerr(SSL_F_DTLS1_HANDLE_TIMEOUT,SSL_R_READ_TIMEOUT_EXPIRED); return 0; } state->timeout.read_timeouts++; if ( state->timeout.read_timeouts > DTLS1_TMO_READ_COUNT) { state->timeout.read_timeouts = 1; } dtls1_start_timer(s); return dtls1_retransmit_buffered_messages(s); } static void get_current_time(struct timeval *t) { #ifdef OPENSSL_SYS_WIN32 struct _timeb tb; _ftime(&tb); t->tv_sec = (long)tb.time; t->tv_usec = (long)tb.millitm * 1000; #elif defined(OPENSSL_SYS_VMS) struct timeb tb; ftime(&tb); t->tv_sec = (long)tb.time; t->tv_usec = (long)tb.millitm * 1000; #else gettimeofday(t, NULL); #endif } int dtls1_listen(SSL *s, struct sockaddr *client) { int ret; SSL_set_options(s, SSL_OP_COOKIE_EXCHANGE); s->d1->listen = 1; ret = SSL_accept(s); if (ret <= 0) return ret; (void) BIO_dgram_get_peer(SSL_get_rbio(s), client); return 1; }