/* * Copyright 2005-2021 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the Apache License 2.0 (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 #include "../ssl_local.h" #include #include #include "record_local.h" #include "internal/packet.h" #include "internal/cryptlib.h" int DTLS_RECORD_LAYER_new(RECORD_LAYER *rl) { DTLS_RECORD_LAYER *d; if ((d = OPENSSL_malloc(sizeof(*d))) == NULL) { ERR_raise(ERR_LIB_SSL, ERR_R_MALLOC_FAILURE); 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) { if (rl->d == NULL) return; 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; if (rl->s->options & SSL_OP_CLEANSE_PLAINTEXT) OPENSSL_cleanse(rdata->rbuf.buf, rdata->rbuf.len); 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; if (rl->s->options & SSL_OP_CLEANSE_PLAINTEXT) OPENSSL_cleanse(rdata->rbuf.buf, rdata->rbuf.len); 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_set_write_sequence(RECORD_LAYER *rl, unsigned char *seq) { memcpy(rl->write_sequence, seq, SEQ_NUM_SIZE); } /* 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); SSLfatal(s, SSL_AD_INTERNAL_ERROR, 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)) { /* SSLfatal() already called */ OPENSSL_free(rdata->rbuf.buf); OPENSSL_free(rdata); pitem_free(item); return -1; } if (pqueue_insert(queue->q, item) == NULL) { /* Must be a duplicate so ignore it */ OPENSSL_free(rdata->rbuf.buf); OPENSSL_free(rdata); pitem_free(item); } 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 */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, 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)) { if (ossl_statem_in_error(s)) { /* dtls1_process_record called SSLfatal() */ return -1; } /* 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) { /* SSLfatal() already called */ 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, size_t len, int peek, size_t *readbytes) { int i, j, iret; size_t 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)) { /* SSLfatal() already called */ return -1; } } if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) || (peek && (type != SSL3_RT_APPLICATION_DATA))) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); return -1; } if (!ossl_statem_get_in_handshake(s) && SSL_in_init(s)) { /* type == SSL3_RT_APPLICATION_DATA */ i = s->handshake_func(s); /* SSLfatal() already called if appropriate */ if (i < 0) return i; if (i == 0) 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; } else if (ossl_statem_in_error(s)) { /* dtls1_handle_timeout() has failed with a fatal error */ return -1; } /* get new packet if necessary */ if ((SSL3_RECORD_get_length(rr) == 0) || (s->rlayer.rstate == SSL_ST_READ_BODY)) { RECORD_LAYER_set_numrpipes(&s->rlayer, 0); iret = dtls1_get_record(s); if (iret <= 0) { iret = dtls1_read_failed(s, iret); /* * Anything other than a timeout is an error. SSLfatal() already * called if appropriate. */ if (iret <= 0) return iret; else goto start; } RECORD_LAYER_set_numrpipes(&s->rlayer, 1); } /* * 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) { /* SSLfatal() already called */ return -1; } SSL3_RECORD_set_length(rr, 0); SSL3_RECORD_set_read(rr); 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); SSL3_RECORD_set_read(rr); 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)) { SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_APP_DATA_IN_HANDSHAKE); return -1; } if (recvd_type != NULL) *recvd_type = SSL3_RECORD_get_type(rr); if (len == 0) { /* * Mark a zero length record as read. This ensures multiple calls to * SSL_read() with a zero length buffer will eventually cause * SSL_pending() to report data as being available. */ if (SSL3_RECORD_get_length(rr) == 0) SSL3_RECORD_set_read(rr); return 0; } if (len > SSL3_RECORD_get_length(rr)) n = SSL3_RECORD_get_length(rr); else n = len; memcpy(buf, &(SSL3_RECORD_get_data(rr)[SSL3_RECORD_get_off(rr)]), n); if (peek) { if (SSL3_RECORD_get_length(rr) == 0) SSL3_RECORD_set_read(rr); } else { if (s->options & SSL_OP_CLEANSE_PLAINTEXT) OPENSSL_cleanse(&(SSL3_RECORD_get_data(rr)[SSL3_RECORD_get_off(rr)]), n); 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); SSL3_RECORD_set_read(rr); } } #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 *readbytes = n; return 1; } /* * If we get here, then type != rr->type; if we have a handshake message, * then it was unexpected (Hello Request or Client Hello). */ if (SSL3_RECORD_get_type(rr) == SSL3_RT_ALERT) { unsigned int alert_level, alert_descr; unsigned char *alert_bytes = SSL3_RECORD_get_data(rr) + SSL3_RECORD_get_off(rr); PACKET alert; if (!PACKET_buf_init(&alert, alert_bytes, SSL3_RECORD_get_length(rr)) || !PACKET_get_1(&alert, &alert_level) || !PACKET_get_1(&alert, &alert_descr) || PACKET_remaining(&alert) != 0) { SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_INVALID_ALERT); return -1; } if (s->msg_callback) s->msg_callback(0, s->version, SSL3_RT_ALERT, alert_bytes, 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; SSL3_RECORD_set_read(rr); s->rlayer.alert_count++; if (s->rlayer.alert_count == MAX_WARN_ALERT_COUNT) { SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_TOO_MANY_WARN_ALERTS); return -1; } 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; } } else if (alert_level == SSL3_AL_FATAL) { s->rwstate = SSL_NOTHING; s->s3.fatal_alert = alert_descr; SSLfatal_data(s, SSL_AD_NO_ALERT, SSL_AD_REASON_OFFSET + alert_descr, "SSL alert number %d", alert_descr); s->shutdown |= SSL_RECEIVED_SHUTDOWN; SSL3_RECORD_set_read(rr); SSL_CTX_remove_session(s->session_ctx, s->session); return 0; } else { SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_UNKNOWN_ALERT_TYPE); return -1; } 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); SSL3_RECORD_set_read(rr); 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); SSL3_RECORD_set_read(rr); goto start; } /* * Unexpected handshake message (Client Hello, or protocol violation) */ if ((SSL3_RECORD_get_type(rr) == SSL3_RT_HANDSHAKE) && !ossl_statem_get_in_handshake(s)) { struct hm_header_st msg_hdr; /* * This may just be a stale retransmit. Also sanity check that we have * at least enough record bytes for a message header */ if (SSL3_RECORD_get_epoch(rr) != s->rlayer.d->r_epoch || SSL3_RECORD_get_length(rr) < DTLS1_HM_HEADER_LENGTH) { SSL3_RECORD_set_length(rr, 0); SSL3_RECORD_set_read(rr); goto start; } dtls1_get_message_header(rr->data, &msg_hdr); /* * 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) { /* SSLfatal) already called */ return -1; } if (dtls1_retransmit_buffered_messages(s) <= 0) { /* Fail if we encountered a fatal error */ if (ossl_statem_in_error(s)) return -1; } SSL3_RECORD_set_length(rr, 0); SSL3_RECORD_set_read(rr); if (!(s->mode & SSL_MODE_AUTO_RETRY)) { if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) { /* no read-ahead left? */ BIO *bio; s->rwstate = SSL_READING; bio = SSL_get_rbio(s); BIO_clear_retry_flags(bio); BIO_set_retry_read(bio); return -1; } } goto start; } /* * To get here we must be trying to read app data but found handshake * data. But if we're trying to read app data, and we're not in init * (which is tested for at the top of this function) then init must be * finished */ if (!ossl_assert(SSL_is_init_finished(s))) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); return -1; } /* We found handshake data, so we're going back into init */ ossl_statem_set_in_init(s, 1); i = s->handshake_func(s); /* SSLfatal() called if appropriate */ if (i < 0) return i; if (i == 0) 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: SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_RECORD); return -1; 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 */ SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, ERR_R_INTERNAL_ERROR); return -1; 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 { SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_RECORD); return -1; } } /* not reached */ } /* * 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, size_t len, size_t *written) { int i; if (!ossl_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); return -1; } s->rwstate = SSL_NOTHING; i = do_dtls1_write(s, type, buf, len, 0, written); return i; } int do_dtls1_write(SSL *s, int type, const unsigned char *buf, size_t len, int create_empty_fragment, size_t *written) { unsigned char *p, *pseq; int i, mac_size, clear = 0; size_t prefix_len = 0; int eivlen; SSL3_RECORD wr; SSL3_BUFFER *wb; SSL_SESSION *sess; wb = &s->rlayer.wbuf[0]; /* * DTLS writes whole datagrams, so there can't be anything left in * the buffer. */ if (!ossl_assert(SSL3_BUFFER_get_left(wb) == 0)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); return 0; } /* 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 > ssl_get_max_send_fragment(s)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, 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) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_EXCEEDS_MAX_FRAGMENT_SIZE); return -1; } } 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, 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)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_COMPRESSION_FAILURE); return -1; } } 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 (!SSL_WRITE_ETM(s) && mac_size != 0) { if (!s->method->ssl3_enc->mac(s, &wr, &(p[SSL3_RECORD_get_length(&wr) + eivlen]), 1)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); return -1; } 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, NULL, mac_size) < 1) { if (!ossl_statem_in_error(s)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); } return -1; } if (SSL_WRITE_ETM(s) && mac_size != 0) { if (!s->method->ssl3_enc->mac(s, &wr, &(p[SSL3_RECORD_get_length(&wr)]), 1)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); return -1; } SSL3_RECORD_add_length(&wr, mac_size); } /* record length after mac and block padding */ /* there's only one epoch between handshake and app data */ s2n(s->rlayer.d->w_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 */ *written = wr.length; return 1; } /* 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. Calls SSLfatal() as required. */ return ssl3_write_pending(s, type, buf, len, written); } 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); }