/* * Copyright 2005-2018 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the OpenSSL license (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy * in the file LICENSE in the source distribution or at * https://www.openssl.org/source/license.html */ #include #include #define USE_SOCKETS #include "../ssl_locl.h" #include #include #include "record_locl.h" int DTLS_RECORD_LAYER_new(RECORD_LAYER *rl) { DTLS_RECORD_LAYER *d; if ((d = OPENSSL_malloc(sizeof(*d))) == NULL) return (0); rl->d = d; d->unprocessed_rcds.q = pqueue_new(); d->processed_rcds.q = pqueue_new(); d->buffered_app_data.q = pqueue_new(); if (d->unprocessed_rcds.q == NULL || d->processed_rcds.q == NULL || d->buffered_app_data.q == NULL) { pqueue_free(d->unprocessed_rcds.q); pqueue_free(d->processed_rcds.q); pqueue_free(d->buffered_app_data.q); OPENSSL_free(d); rl->d = NULL; return (0); } return 1; } void DTLS_RECORD_LAYER_free(RECORD_LAYER *rl) { DTLS_RECORD_LAYER_clear(rl); pqueue_free(rl->d->unprocessed_rcds.q); pqueue_free(rl->d->processed_rcds.q); pqueue_free(rl->d->buffered_app_data.q); OPENSSL_free(rl->d); rl->d = NULL; } void DTLS_RECORD_LAYER_clear(RECORD_LAYER *rl) { DTLS_RECORD_LAYER *d; pitem *item = NULL; DTLS1_RECORD_DATA *rdata; pqueue *unprocessed_rcds; pqueue *processed_rcds; pqueue *buffered_app_data; d = rl->d; while ((item = pqueue_pop(d->unprocessed_rcds.q)) != NULL) { rdata = (DTLS1_RECORD_DATA *)item->data; OPENSSL_free(rdata->rbuf.buf); OPENSSL_free(item->data); pitem_free(item); } while ((item = pqueue_pop(d->processed_rcds.q)) != NULL) { rdata = (DTLS1_RECORD_DATA *)item->data; OPENSSL_free(rdata->rbuf.buf); OPENSSL_free(item->data); pitem_free(item); } while ((item = pqueue_pop(d->buffered_app_data.q)) != NULL) { rdata = (DTLS1_RECORD_DATA *)item->data; OPENSSL_free(rdata->rbuf.buf); OPENSSL_free(item->data); pitem_free(item); } unprocessed_rcds = d->unprocessed_rcds.q; processed_rcds = d->processed_rcds.q; buffered_app_data = d->buffered_app_data.q; memset(d, 0, sizeof(*d)); d->unprocessed_rcds.q = unprocessed_rcds; d->processed_rcds.q = processed_rcds; d->buffered_app_data.q = buffered_app_data; } void DTLS_RECORD_LAYER_set_saved_w_epoch(RECORD_LAYER *rl, unsigned short e) { if (e == rl->d->w_epoch - 1) { memcpy(rl->d->curr_write_sequence, rl->write_sequence, sizeof(rl->write_sequence)); memcpy(rl->write_sequence, rl->d->last_write_sequence, sizeof(rl->write_sequence)); } else if (e == rl->d->w_epoch + 1) { memcpy(rl->d->last_write_sequence, rl->write_sequence, sizeof(unsigned char[8])); memcpy(rl->write_sequence, rl->d->curr_write_sequence, sizeof(rl->write_sequence)); } rl->d->w_epoch = e; } void DTLS_RECORD_LAYER_resync_write(RECORD_LAYER *rl) { memcpy(rl->write_sequence, rl->read_sequence, sizeof(rl->write_sequence)); } void DTLS_RECORD_LAYER_set_write_sequence(RECORD_LAYER *rl, unsigned char *seq) { memcpy(rl->write_sequence, seq, SEQ_NUM_SIZE); } static int have_handshake_fragment(SSL *s, int type, unsigned char *buf, int len); /* copy buffered record into SSL structure */ static int dtls1_copy_record(SSL *s, pitem *item) { DTLS1_RECORD_DATA *rdata; rdata = (DTLS1_RECORD_DATA *)item->data; SSL3_BUFFER_release(&s->rlayer.rbuf); s->rlayer.packet = rdata->packet; s->rlayer.packet_length = rdata->packet_length; memcpy(&s->rlayer.rbuf, &(rdata->rbuf), sizeof(SSL3_BUFFER)); memcpy(&s->rlayer.rrec, &(rdata->rrec), sizeof(SSL3_RECORD)); /* Set proper sequence number for mac calculation */ memcpy(&(s->rlayer.read_sequence[2]), &(rdata->packet[5]), 6); return (1); } int dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority) { DTLS1_RECORD_DATA *rdata; pitem *item; /* Limit the size of the queue to prevent DOS attacks */ if (pqueue_size(queue->q) >= 100) return 0; rdata = OPENSSL_malloc(sizeof(*rdata)); item = pitem_new(priority, rdata); if (rdata == NULL || item == NULL) { OPENSSL_free(rdata); pitem_free(item); SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR); return -1; } rdata->packet = s->rlayer.packet; rdata->packet_length = s->rlayer.packet_length; memcpy(&(rdata->rbuf), &s->rlayer.rbuf, sizeof(SSL3_BUFFER)); memcpy(&(rdata->rrec), &s->rlayer.rrec, sizeof(SSL3_RECORD)); item->data = rdata; #ifndef OPENSSL_NO_SCTP /* Store bio_dgram_sctp_rcvinfo struct */ if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && (SSL_get_state(s) == TLS_ST_SR_FINISHED || SSL_get_state(s) == TLS_ST_CR_FINISHED)) { BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO, sizeof(rdata->recordinfo), &rdata->recordinfo); } #endif s->rlayer.packet = NULL; s->rlayer.packet_length = 0; memset(&s->rlayer.rbuf, 0, sizeof(s->rlayer.rbuf)); memset(&s->rlayer.rrec, 0, sizeof(s->rlayer.rrec)); if (!ssl3_setup_buffers(s)) { SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR); OPENSSL_free(rdata->rbuf.buf); OPENSSL_free(rdata); pitem_free(item); return (-1); } /* insert should not fail, since duplicates are dropped */ if (pqueue_insert(queue->q, item) == NULL) { SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR); OPENSSL_free(rdata->rbuf.buf); OPENSSL_free(rdata); pitem_free(item); return (-1); } return (1); } int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue) { pitem *item; item = pqueue_pop(queue->q); if (item) { dtls1_copy_record(s, item); OPENSSL_free(item->data); pitem_free(item); return (1); } return (0); } /* * retrieve a buffered record that belongs to the new epoch, i.e., not * processed yet */ #define dtls1_get_unprocessed_record(s) \ dtls1_retrieve_buffered_record((s), \ &((s)->rlayer.d->unprocessed_rcds)) int dtls1_process_buffered_records(SSL *s) { pitem *item; SSL3_BUFFER *rb; SSL3_RECORD *rr; DTLS1_BITMAP *bitmap; unsigned int is_next_epoch; int replayok = 1; item = pqueue_peek(s->rlayer.d->unprocessed_rcds.q); if (item) { /* Check if epoch is current. */ if (s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch) return 1; /* Nothing to do. */ rr = RECORD_LAYER_get_rrec(&s->rlayer); rb = RECORD_LAYER_get_rbuf(&s->rlayer); if (SSL3_BUFFER_get_left(rb) > 0) { /* * We've still got data from the current packet to read. There could * be a record from the new epoch in it - so don't overwrite it * with the unprocessed records yet (we'll do it when we've * finished reading the current packet). */ return 1; } /* Process all the records. */ while (pqueue_peek(s->rlayer.d->unprocessed_rcds.q)) { dtls1_get_unprocessed_record(s); bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch); if (bitmap == NULL) { /* * Should not happen. This will only ever be NULL when the * current record is from a different epoch. But that cannot * be the case because we already checked the epoch above */ SSLerr(SSL_F_DTLS1_PROCESS_BUFFERED_RECORDS, ERR_R_INTERNAL_ERROR); return 0; } #ifndef OPENSSL_NO_SCTP /* Only do replay check if no SCTP bio */ if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) #endif { /* * Check whether this is a repeat, or aged record. We did this * check once already when we first received the record - but * we might have updated the window since then due to * records we subsequently processed. */ replayok = dtls1_record_replay_check(s, bitmap); } if (!replayok || !dtls1_process_record(s, bitmap)) { /* dump this record */ rr->length = 0; RECORD_LAYER_reset_packet_length(&s->rlayer); continue; } if (dtls1_buffer_record(s, &(s->rlayer.d->processed_rcds), SSL3_RECORD_get_seq_num(s->rlayer.rrec)) < 0) return 0; } } /* * sync epoch numbers once all the unprocessed records have been * processed */ s->rlayer.d->processed_rcds.epoch = s->rlayer.d->r_epoch; s->rlayer.d->unprocessed_rcds.epoch = s->rlayer.d->r_epoch + 1; return 1; } /*- * Return up to 'len' payload bytes received in 'type' records. * 'type' is one of the following: * * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) * - 0 (during a shutdown, no data has to be returned) * * If we don't have stored data to work from, read a SSL/TLS record first * (possibly multiple records if we still don't have anything to return). * * This function must handle any surprises the peer may have for us, such as * Alert records (e.g. close_notify) or renegotiation requests. ChangeCipherSpec * messages are treated as if they were handshake messages *if* the |recd_type| * argument is non NULL. * Also if record payloads contain fragments too small to process, we store * them until there is enough for the respective protocol (the record protocol * may use arbitrary fragmentation and even interleaving): * Change cipher spec protocol * just 1 byte needed, no need for keeping anything stored * Alert protocol * 2 bytes needed (AlertLevel, AlertDescription) * Handshake protocol * 4 bytes needed (HandshakeType, uint24 length) -- we just have * to detect unexpected Client Hello and Hello Request messages * here, anything else is handled by higher layers * Application data protocol * none of our business */ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf, int len, int peek) { int al, i, j, ret; unsigned int n; SSL3_RECORD *rr; void (*cb) (const SSL *ssl, int type2, int val) = NULL; if (!SSL3_BUFFER_is_initialised(&s->rlayer.rbuf)) { /* Not initialized yet */ if (!ssl3_setup_buffers(s)) return (-1); } if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) || (peek && (type != SSL3_RT_APPLICATION_DATA))) { SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); return -1; } /* * check whether there's a handshake message (client hello?) waiting */ if ((ret = have_handshake_fragment(s, type, buf, len))) { *recvd_type = SSL3_RT_HANDSHAKE; return ret; } /* * Now s->rlayer.d->handshake_fragment_len == 0 if * type == SSL3_RT_HANDSHAKE. */ if (!ossl_statem_get_in_handshake(s) && SSL_in_init(s)) { /* type == SSL3_RT_APPLICATION_DATA */ i = s->handshake_func(s); if (i < 0) return (i); if (i == 0) { SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); return (-1); } } start: s->rwstate = SSL_NOTHING; /*- * s->s3->rrec.type - is the type of record * s->s3->rrec.data, - data * s->s3->rrec.off, - offset into 'data' for next read * s->s3->rrec.length, - number of bytes. */ rr = s->rlayer.rrec; /* * We are not handshaking and have no data yet, so process data buffered * during the last handshake in advance, if any. */ if (SSL_is_init_finished(s) && SSL3_RECORD_get_length(rr) == 0) { pitem *item; item = pqueue_pop(s->rlayer.d->buffered_app_data.q); if (item) { #ifndef OPENSSL_NO_SCTP /* Restore bio_dgram_sctp_rcvinfo struct */ if (BIO_dgram_is_sctp(SSL_get_rbio(s))) { DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data; BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO, sizeof(rdata->recordinfo), &rdata->recordinfo); } #endif dtls1_copy_record(s, item); OPENSSL_free(item->data); pitem_free(item); } } /* Check for timeout */ if (dtls1_handle_timeout(s) > 0) goto start; /* get new packet if necessary */ if ((SSL3_RECORD_get_length(rr) == 0) || (s->rlayer.rstate == SSL_ST_READ_BODY)) { ret = dtls1_get_record(s); if (ret <= 0) { ret = dtls1_read_failed(s, ret); /* anything other than a timeout is an error */ if (ret <= 0) return (ret); else goto start; } } /* * Reset the count of consecutive warning alerts if we've got a non-empty * record that isn't an alert. */ if (SSL3_RECORD_get_type(rr) != SSL3_RT_ALERT && SSL3_RECORD_get_length(rr) != 0) s->rlayer.alert_count = 0; /* we now have a packet which can be read and processed */ if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, * reset by ssl3_get_finished */ && (SSL3_RECORD_get_type(rr) != SSL3_RT_HANDSHAKE)) { /* * We now have application data between CCS and Finished. Most likely * the packets were reordered on their way, so buffer the application * data for later processing rather than dropping the connection. */ if (dtls1_buffer_record(s, &(s->rlayer.d->buffered_app_data), SSL3_RECORD_get_seq_num(rr)) < 0) { SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); return -1; } SSL3_RECORD_set_length(rr, 0); goto start; } /* * If the other end has shut down, throw anything we read away (even in * 'peek' mode) */ if (s->shutdown & SSL_RECEIVED_SHUTDOWN) { SSL3_RECORD_set_length(rr, 0); s->rwstate = SSL_NOTHING; return (0); } if (type == SSL3_RECORD_get_type(rr) || (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC && type == SSL3_RT_HANDSHAKE && recvd_type != NULL)) { /* * SSL3_RT_APPLICATION_DATA or * SSL3_RT_HANDSHAKE or * SSL3_RT_CHANGE_CIPHER_SPEC */ /* * make sure that we are not getting application data when we are * doing a handshake for the first time */ if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && (s->enc_read_ctx == NULL)) { al = SSL_AD_UNEXPECTED_MESSAGE; SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE); goto f_err; } if (recvd_type != NULL) *recvd_type = SSL3_RECORD_get_type(rr); if (len <= 0) return (len); if ((unsigned int)len > SSL3_RECORD_get_length(rr)) n = SSL3_RECORD_get_length(rr); else n = (unsigned int)len; memcpy(buf, &(SSL3_RECORD_get_data(rr)[SSL3_RECORD_get_off(rr)]), n); if (!peek) { SSL3_RECORD_sub_length(rr, n); SSL3_RECORD_add_off(rr, n); if (SSL3_RECORD_get_length(rr) == 0) { s->rlayer.rstate = SSL_ST_READ_HEADER; SSL3_RECORD_set_off(rr, 0); } } #ifndef OPENSSL_NO_SCTP /* * We might had to delay a close_notify alert because of reordered * app data. If there was an alert and there is no message to read * anymore, finally set shutdown. */ if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && s->d1->shutdown_received && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) { s->shutdown |= SSL_RECEIVED_SHUTDOWN; return (0); } #endif return (n); } /* * If we get here, then type != rr->type; if we have a handshake message, * then it was unexpected (Hello Request or Client Hello). */ /* * In case of record types for which we have 'fragment' storage, fill * that so that we can process the data at a fixed place. */ { unsigned int k, dest_maxlen = 0; unsigned char *dest = NULL; unsigned int *dest_len = NULL; if (SSL3_RECORD_get_type(rr) == SSL3_RT_HANDSHAKE) { dest_maxlen = sizeof(s->rlayer.d->handshake_fragment); dest = s->rlayer.d->handshake_fragment; dest_len = &s->rlayer.d->handshake_fragment_len; } else if (SSL3_RECORD_get_type(rr) == SSL3_RT_ALERT) { dest_maxlen = sizeof(s->rlayer.d->alert_fragment); dest = s->rlayer.d->alert_fragment; dest_len = &s->rlayer.d->alert_fragment_len; } #ifndef OPENSSL_NO_HEARTBEATS else if (SSL3_RECORD_get_type(rr) == DTLS1_RT_HEARTBEAT) { /* We allow a 0 return */ if (dtls1_process_heartbeat(s, SSL3_RECORD_get_data(rr), SSL3_RECORD_get_length(rr)) < 0) { return -1; } /* Exit and notify application to read again */ SSL3_RECORD_set_length(rr, 0); s->rwstate = SSL_READING; BIO_clear_retry_flags(SSL_get_rbio(s)); BIO_set_retry_read(SSL_get_rbio(s)); return (-1); } #endif /* else it's a CCS message, or application data or wrong */ else if (SSL3_RECORD_get_type(rr) != SSL3_RT_CHANGE_CIPHER_SPEC) { /* * Application data while renegotiating is allowed. Try again * reading. */ if (SSL3_RECORD_get_type(rr) == SSL3_RT_APPLICATION_DATA) { BIO *bio; s->s3->in_read_app_data = 2; bio = SSL_get_rbio(s); s->rwstate = SSL_READING; BIO_clear_retry_flags(bio); BIO_set_retry_read(bio); return (-1); } /* Not certain if this is the right error handling */ al = SSL_AD_UNEXPECTED_MESSAGE; SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); goto f_err; } if (dest_maxlen > 0) { /* * XDTLS: In a pathological case, the Client Hello may be * fragmented--don't always expect dest_maxlen bytes */ if (SSL3_RECORD_get_length(rr) < dest_maxlen) { #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE /* * for normal alerts rr->length is 2, while * dest_maxlen is 7 if we were to handle this * non-existing alert... */ FIX ME; #endif s->rlayer.rstate = SSL_ST_READ_HEADER; SSL3_RECORD_set_length(rr, 0); goto start; } /* now move 'n' bytes: */ for (k = 0; k < dest_maxlen; k++) { dest[k] = SSL3_RECORD_get_data(rr)[SSL3_RECORD_get_off(rr)]; SSL3_RECORD_add_off(rr, 1); SSL3_RECORD_add_length(rr, -1); } *dest_len = dest_maxlen; } } /*- * s->rlayer.d->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE; * s->rlayer.d->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT. * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */ /* If we are a client, check for an incoming 'Hello Request': */ if ((!s->server) && (s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) && (s->rlayer.d->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && (s->session != NULL) && (s->session->cipher != NULL)) { s->rlayer.d->handshake_fragment_len = 0; if ((s->rlayer.d->handshake_fragment[1] != 0) || (s->rlayer.d->handshake_fragment[2] != 0) || (s->rlayer.d->handshake_fragment[3] != 0)) { al = SSL_AD_DECODE_ERROR; SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_HELLO_REQUEST); goto f_err; } /* * no need to check sequence number on HELLO REQUEST messages */ if (s->msg_callback) s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->rlayer.d->handshake_fragment, 4, s, s->msg_callback_arg); if (SSL_is_init_finished(s) && (s->options & SSL_OP_NO_RENEGOTIATION) == 0 && !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && !s->s3->renegotiate) { s->d1->handshake_read_seq++; s->new_session = 1; ssl3_renegotiate(s); if (ssl3_renegotiate_check(s)) { i = s->handshake_func(s); if (i < 0) return (i); if (i == 0) { SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); return (-1); } if (!(s->mode & SSL_MODE_AUTO_RETRY)) { if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) { /* no read-ahead left? */ BIO *bio; /* * In the case where we try to read application data, * but we trigger an SSL handshake, we return -1 with * the retry option set. Otherwise renegotiation may * cause nasty problems in the blocking world */ s->rwstate = SSL_READING; bio = SSL_get_rbio(s); BIO_clear_retry_flags(bio); BIO_set_retry_read(bio); return (-1); } } } } else { SSL3_RECORD_set_length(rr, 0); ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); } /* * we either finished a handshake or ignored the request, now try * again to obtain the (application) data we were asked for */ goto start; } /* * If we are a server and get a client hello when renegotiation isn't * allowed send back a no renegotiation alert and carry on. */ if (s->server && SSL_is_init_finished(s) && s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH && s->rlayer.d->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO && s->s3->previous_client_finished_len != 0 && ((!s->s3->send_connection_binding && (s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION) == 0) || (s->options & SSL_OP_NO_RENEGOTIATION) != 0)) { s->rlayer.d->handshake_fragment_len = 0; SSL3_RECORD_set_length(rr, 0); ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); goto start; } if (s->rlayer.d->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) { int alert_level = s->rlayer.d->alert_fragment[0]; int alert_descr = s->rlayer.d->alert_fragment[1]; s->rlayer.d->alert_fragment_len = 0; if (s->msg_callback) s->msg_callback(0, s->version, SSL3_RT_ALERT, s->rlayer.d->alert_fragment, 2, s, s->msg_callback_arg); if (s->info_callback != NULL) cb = s->info_callback; else if (s->ctx->info_callback != NULL) cb = s->ctx->info_callback; if (cb != NULL) { j = (alert_level << 8) | alert_descr; cb(s, SSL_CB_READ_ALERT, j); } if (alert_level == SSL3_AL_WARNING) { s->s3->warn_alert = alert_descr; s->rlayer.alert_count++; if (s->rlayer.alert_count == MAX_WARN_ALERT_COUNT) { al = SSL_AD_UNEXPECTED_MESSAGE; SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_TOO_MANY_WARN_ALERTS); goto f_err; } if (alert_descr == SSL_AD_CLOSE_NOTIFY) { #ifndef OPENSSL_NO_SCTP /* * With SCTP and streams the socket may deliver app data * after a close_notify alert. We have to check this first so * that nothing gets discarded. */ if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) { s->d1->shutdown_received = 1; s->rwstate = SSL_READING; BIO_clear_retry_flags(SSL_get_rbio(s)); BIO_set_retry_read(SSL_get_rbio(s)); return -1; } #endif s->shutdown |= SSL_RECEIVED_SHUTDOWN; return (0); } #if 0 /* XXX: this is a possible improvement in the future */ /* now check if it's a missing record */ if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) { unsigned short seq; unsigned int frag_off; unsigned char *p = &(s->rlayer.d->alert_fragment[2]); n2s(p, seq); n2l3(p, frag_off); dtls1_retransmit_message(s, dtls1_get_queue_priority (frag->msg_header.seq, 0), frag_off, &found); if (!found && SSL_in_init(s)) { /* * fprintf( stderr,"in init = %d\n", SSL_in_init(s)); */ /* * requested a message not yet sent, send an alert * ourselves */ ssl3_send_alert(s, SSL3_AL_WARNING, DTLS1_AD_MISSING_HANDSHAKE_MESSAGE); } } #endif } else if (alert_level == SSL3_AL_FATAL) { char tmp[16]; s->rwstate = SSL_NOTHING; s->s3->fatal_alert = alert_descr; SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr); BIO_snprintf(tmp, sizeof(tmp), "%d", alert_descr); ERR_add_error_data(2, "SSL alert number ", tmp); s->shutdown |= SSL_RECEIVED_SHUTDOWN; SSL_CTX_remove_session(s->session_ctx, s->session); return (0); } else { al = SSL_AD_ILLEGAL_PARAMETER; SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE); goto f_err; } goto start; } if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a * shutdown */ s->rwstate = SSL_NOTHING; SSL3_RECORD_set_length(rr, 0); return (0); } if (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC) { /* * We can't process a CCS now, because previous handshake messages * are still missing, so just drop it. */ SSL3_RECORD_set_length(rr, 0); goto start; } /* * Unexpected handshake message (Client Hello, or protocol violation) */ if ((s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) && !ossl_statem_get_in_handshake(s)) { struct hm_header_st msg_hdr; /* this may just be a stale retransmit */ dtls1_get_message_header(rr->data, &msg_hdr); if (SSL3_RECORD_get_epoch(rr) != s->rlayer.d->r_epoch) { SSL3_RECORD_set_length(rr, 0); goto start; } /* * If we are server, we may have a repeated FINISHED of the client * here, then retransmit our CCS and FINISHED. */ if (msg_hdr.type == SSL3_MT_FINISHED) { if (dtls1_check_timeout_num(s) < 0) return -1; dtls1_retransmit_buffered_messages(s); SSL3_RECORD_set_length(rr, 0); goto start; } if (SSL_is_init_finished(s) && !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) { ossl_statem_set_in_init(s, 1); s->renegotiate = 1; s->new_session = 1; } i = s->handshake_func(s); if (i < 0) return (i); if (i == 0) { SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); return (-1); } if (!(s->mode & SSL_MODE_AUTO_RETRY)) { if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) { /* no read-ahead left? */ BIO *bio; /* * In the case where we try to read application data, but we * trigger an SSL handshake, we return -1 with the retry * option set. Otherwise renegotiation may cause nasty * problems in the blocking world */ s->rwstate = SSL_READING; bio = SSL_get_rbio(s); BIO_clear_retry_flags(bio); BIO_set_retry_read(bio); return (-1); } } goto start; } switch (SSL3_RECORD_get_type(rr)) { default: /* TLS just ignores unknown message types */ if (s->version == TLS1_VERSION) { SSL3_RECORD_set_length(rr, 0); goto start; } al = SSL_AD_UNEXPECTED_MESSAGE; SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); goto f_err; case SSL3_RT_CHANGE_CIPHER_SPEC: case SSL3_RT_ALERT: case SSL3_RT_HANDSHAKE: /* * we already handled all of these, with the possible exception of * SSL3_RT_HANDSHAKE when ossl_statem_get_in_handshake(s) is true, but * that should not happen when type != rr->type */ al = SSL_AD_UNEXPECTED_MESSAGE; SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); goto f_err; case SSL3_RT_APPLICATION_DATA: /* * At this point, we were expecting handshake data, but have * application data. If the library was running inside ssl3_read() * (i.e. in_read_app_data is set) and it makes sense to read * application data at this point (session renegotiation not yet * started), we will indulge it. */ if (s->s3->in_read_app_data && (s->s3->total_renegotiations != 0) && ossl_statem_app_data_allowed(s)) { s->s3->in_read_app_data = 2; return (-1); } else { al = SSL_AD_UNEXPECTED_MESSAGE; SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); goto f_err; } } /* not reached */ f_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); return (-1); } /* * this only happens when a client hello is received and a handshake * is started. */ static int have_handshake_fragment(SSL *s, int type, unsigned char *buf, int len) { if ((type == SSL3_RT_HANDSHAKE) && (s->rlayer.d->handshake_fragment_len > 0)) /* (partially) satisfy request from storage */ { unsigned char *src = s->rlayer.d->handshake_fragment; unsigned char *dst = buf; unsigned int k, n; /* peek == 0 */ n = 0; while ((len > 0) && (s->rlayer.d->handshake_fragment_len > 0)) { *dst++ = *src++; len--; s->rlayer.d->handshake_fragment_len--; n++; } /* move any remaining fragment bytes: */ for (k = 0; k < s->rlayer.d->handshake_fragment_len; k++) s->rlayer.d->handshake_fragment[k] = *src++; return n; } return 0; } /* * Call this to write data in records of type 'type' It will return <= 0 if * not all data has been sent or non-blocking IO. */ int dtls1_write_bytes(SSL *s, int type, const void *buf, int len) { int i; OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH); s->rwstate = SSL_NOTHING; i = do_dtls1_write(s, type, buf, len, 0); return i; } int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, int create_empty_fragment) { unsigned char *p, *pseq; int i, mac_size, clear = 0; int prefix_len = 0; int eivlen; SSL3_RECORD wr; SSL3_BUFFER *wb; SSL_SESSION *sess; wb = &s->rlayer.wbuf[0]; /* * first check if there is a SSL3_BUFFER still being written out. This * will happen with non blocking IO */ if (SSL3_BUFFER_get_left(wb) != 0) { OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */ return (ssl3_write_pending(s, type, buf, len)); } /* If we have an alert to send, lets send it */ if (s->s3->alert_dispatch) { i = s->method->ssl_dispatch_alert(s); if (i <= 0) return (i); /* if it went, fall through and send more stuff */ } if (len == 0 && !create_empty_fragment) return 0; if (len > s->max_send_fragment) { SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_EXCEEDS_MAX_FRAGMENT_SIZE); return 0; } sess = s->session; if ((sess == NULL) || (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL)) clear = 1; if (clear) mac_size = 0; else { mac_size = EVP_MD_CTX_size(s->write_hash); if (mac_size < 0) goto err; } p = SSL3_BUFFER_get_buf(wb) + prefix_len; /* write the header */ *(p++) = type & 0xff; SSL3_RECORD_set_type(&wr, type); /* * Special case: for hello verify request, client version 1.0 and we * haven't decided which version to use yet send back using version 1.0 * header: otherwise some clients will ignore it. */ if (s->method->version == DTLS_ANY_VERSION && s->max_proto_version != DTLS1_BAD_VER) { *(p++) = DTLS1_VERSION >> 8; *(p++) = DTLS1_VERSION & 0xff; } else { *(p++) = s->version >> 8; *(p++) = s->version & 0xff; } /* field where we are to write out packet epoch, seq num and len */ pseq = p; p += 10; /* Explicit IV length, block ciphers appropriate version flag */ if (s->enc_write_ctx) { int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); if (mode == EVP_CIPH_CBC_MODE) { eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); if (eivlen <= 1) eivlen = 0; } /* Need explicit part of IV for GCM mode */ else if (mode == EVP_CIPH_GCM_MODE) eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; else if (mode == EVP_CIPH_CCM_MODE) eivlen = EVP_CCM_TLS_EXPLICIT_IV_LEN; else eivlen = 0; } else eivlen = 0; /* lets setup the record stuff. */ SSL3_RECORD_set_data(&wr, p + eivlen); /* make room for IV in case of CBC */ SSL3_RECORD_set_length(&wr, (int)len); SSL3_RECORD_set_input(&wr, (unsigned char *)buf); /* * we now 'read' from wr.input, wr.length bytes into wr.data */ /* first we compress */ if (s->compress != NULL) { if (!ssl3_do_compress(s, &wr)) { SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_COMPRESSION_FAILURE); goto err; } } else { memcpy(SSL3_RECORD_get_data(&wr), SSL3_RECORD_get_input(&wr), SSL3_RECORD_get_length(&wr)); SSL3_RECORD_reset_input(&wr); } /* * we should still have the output to wr.data and the input from * wr.input. Length should be wr.length. wr.data still points in the * wb->buf */ if (mac_size != 0) { if (s->method->ssl3_enc->mac(s, &wr, &(p[SSL3_RECORD_get_length(&wr) + eivlen]), 1) < 0) goto err; SSL3_RECORD_add_length(&wr, mac_size); } /* this is true regardless of mac size */ SSL3_RECORD_set_data(&wr, p); SSL3_RECORD_reset_input(&wr); if (eivlen) SSL3_RECORD_add_length(&wr, eivlen); if (s->method->ssl3_enc->enc(s, &wr, 1, 1) < 1) goto err; /* record length after mac and block padding */ /* * if (type == SSL3_RT_APPLICATION_DATA || (type == SSL3_RT_ALERT && ! * SSL_in_init(s))) */ /* there's only one epoch between handshake and app data */ s2n(s->rlayer.d->w_epoch, pseq); /* XDTLS: ?? */ /* * else s2n(s->d1->handshake_epoch, pseq); */ memcpy(pseq, &(s->rlayer.write_sequence[2]), 6); pseq += 6; s2n(SSL3_RECORD_get_length(&wr), pseq); if (s->msg_callback) s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH, DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg); /* * we should now have wr.data pointing to the encrypted data, which is * wr->length long */ SSL3_RECORD_set_type(&wr, type); /* not needed but helps for debugging */ SSL3_RECORD_add_length(&wr, DTLS1_RT_HEADER_LENGTH); ssl3_record_sequence_update(&(s->rlayer.write_sequence[0])); if (create_empty_fragment) { /* * we are in a recursive call; just return the length, don't write * out anything here */ return wr.length; } /* now let's set up wb */ SSL3_BUFFER_set_left(wb, prefix_len + SSL3_RECORD_get_length(&wr)); SSL3_BUFFER_set_offset(wb, 0); /* * memorize arguments so that ssl3_write_pending can detect bad write * retries later */ s->rlayer.wpend_tot = len; s->rlayer.wpend_buf = buf; s->rlayer.wpend_type = type; s->rlayer.wpend_ret = len; /* we now just need to write the buffer */ return ssl3_write_pending(s, type, buf, len); err: return -1; } DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, unsigned int *is_next_epoch) { *is_next_epoch = 0; /* In current epoch, accept HM, CCS, DATA, & ALERT */ if (rr->epoch == s->rlayer.d->r_epoch) return &s->rlayer.d->bitmap; /* * Only HM and ALERT messages can be from the next epoch and only if we * have already processed all of the unprocessed records from the last * epoch */ else if (rr->epoch == (unsigned long)(s->rlayer.d->r_epoch + 1) && s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch && (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) { *is_next_epoch = 1; return &s->rlayer.d->next_bitmap; } return NULL; } void dtls1_reset_seq_numbers(SSL *s, int rw) { unsigned char *seq; unsigned int seq_bytes = sizeof(s->rlayer.read_sequence); if (rw & SSL3_CC_READ) { seq = s->rlayer.read_sequence; s->rlayer.d->r_epoch++; memcpy(&s->rlayer.d->bitmap, &s->rlayer.d->next_bitmap, sizeof(s->rlayer.d->bitmap)); memset(&s->rlayer.d->next_bitmap, 0, sizeof(s->rlayer.d->next_bitmap)); /* * We must not use any buffered messages received from the previous * epoch */ dtls1_clear_received_buffer(s); } else { seq = s->rlayer.write_sequence; memcpy(s->rlayer.d->last_write_sequence, seq, sizeof(s->rlayer.write_sequence)); s->rlayer.d->w_epoch++; } memset(seq, 0, seq_bytes); }