X-Git-Url: https://git.openssl.org/?p=openssl.git;a=blobdiff_plain;f=ssl%2Fd1_pkt.c;h=4464a305d239857889978d68825f289879667796;hp=dea63d694a548ff0ad9f895afa3e3c0de223cc4a;hb=0c75eeacd3285b395dc75b65c3e6fe6ffbef59f0;hpb=0eab41fb78cf4d7c76e563fd677ab6c32fc28bb0 diff --git a/ssl/d1_pkt.c b/ssl/d1_pkt.c index dea63d694a..4464a305d2 100644 --- a/ssl/d1_pkt.c +++ b/ssl/d1_pkt.c @@ -179,7 +179,6 @@ static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, static int dtls1_buffer_record(SSL *s, record_pqueue *q, unsigned char *priority); static int dtls1_process_record(SSL *s); -static void dtls1_clear_timeouts(SSL *s); /* copy buffered record into SSL structure */ static int @@ -196,6 +195,9 @@ dtls1_copy_record(SSL *s, pitem *item) s->packet_length = rdata->packet_length; memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER)); memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD)); + + /* Set proper sequence number for mac calculation */ + memcpy(&(s->s3->read_sequence[2]), &(rdata->packet[5]), 6); return(1); } @@ -207,6 +209,10 @@ 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(DTLS1_RECORD_DATA)); item = pitem_new(priority, rdata); if (rdata == NULL || item == NULL) @@ -225,6 +231,14 @@ dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority) item->data = rdata; +#ifndef OPENSSL_NO_SCTP + /* Store bio_dgram_sctp_rcvinfo struct */ + if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && + (s->state == SSL3_ST_SR_FINISHED_A || s->state == SSL3_ST_CR_FINISHED_A)) { + BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO, sizeof(rdata->recordinfo), &rdata->recordinfo); + } +#endif + /* insert should not fail, since duplicates are dropped */ if (pqueue_insert(queue->q, item) == NULL) { @@ -289,9 +303,6 @@ dtls1_process_buffered_records(SSL *s) item = pqueue_peek(s->d1->unprocessed_rcds.q); if (item) { - DTLS1_RECORD_DATA *rdata; - rdata = (DTLS1_RECORD_DATA *)item->data; - /* Check if epoch is current. */ if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch) return(1); /* Nothing to do. */ @@ -365,14 +376,12 @@ static int dtls1_process_record(SSL *s) { int i,al; - int clear=0; int enc_err; SSL_SESSION *sess; SSL3_RECORD *rr; unsigned int mac_size; unsigned char md[EVP_MAX_MD_SIZE]; - rr= &(s->s3->rrec); sess = s->session; @@ -401,16 +410,19 @@ dtls1_process_record(SSL *s) /* decrypt in place in 'rr->input' */ rr->data=rr->input; + rr->orig_len=rr->length; enc_err = s->method->ssl3_enc->enc(s,0); - if (enc_err <= 0) + /* enc_err is: + * 0: (in non-constant time) if the record is publically invalid. + * 1: if the padding is valid + * -1: if the padding is invalid */ + if (enc_err == 0) { - if (enc_err == 0) - /* SSLerr() and ssl3_send_alert() have been called */ - goto err; - - /* otherwise enc_err == -1 */ - goto decryption_failed_or_bad_record_mac; + /* For DTLS we simply ignore bad packets. */ + rr->length = 0; + s->packet_length = 0; + goto err; } #ifdef TLS_DEBUG @@ -420,46 +432,64 @@ printf("\n"); #endif /* r->length is now the compressed data plus mac */ - if ( (sess == NULL) || - (s->enc_read_ctx == NULL) || - (s->read_hash == NULL)) - clear=1; - - if (!clear) + if ((sess != NULL) && + (s->enc_read_ctx != NULL) && + (EVP_MD_CTX_md(s->read_hash) != NULL)) { - /* !clear => s->read_hash != NULL => mac_size != -1 */ - int t; - t=EVP_MD_CTX_size(s->read_hash); - OPENSSL_assert(t >= 0); - mac_size=t; - - if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+mac_size) - { -#if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */ - al=SSL_AD_RECORD_OVERFLOW; - SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG); - goto f_err; -#else - goto decryption_failed_or_bad_record_mac; -#endif - } - /* check the MAC for rr->input (it's in mac_size bytes at the tail) */ - if (rr->length < mac_size) + /* s->read_hash != NULL => mac_size != -1 */ + unsigned char *mac = NULL; + unsigned char mac_tmp[EVP_MAX_MD_SIZE]; + mac_size=EVP_MD_CTX_size(s->read_hash); + OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); + + /* orig_len is the length of the record before any padding was + * removed. This is public information, as is the MAC in use, + * therefore we can safely process the record in a different + * amount of time if it's too short to possibly contain a MAC. + */ + if (rr->orig_len < mac_size || + /* CBC records must have a padding length byte too. */ + (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && + rr->orig_len < mac_size+1)) { -#if 0 /* OK only for stream ciphers */ al=SSL_AD_DECODE_ERROR; SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_LENGTH_TOO_SHORT); goto f_err; -#else - goto decryption_failed_or_bad_record_mac; -#endif } - rr->length-=mac_size; - i=s->method->ssl3_enc->mac(s,md,0); - if (i < 0 || memcmp(md,&(rr->data[rr->length]),mac_size) != 0) + + if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) + { + /* We update the length so that the TLS header bytes + * can be constructed correctly but we need to extract + * the MAC in constant time from within the record, + * without leaking the contents of the padding bytes. + * */ + mac = mac_tmp; + ssl3_cbc_copy_mac(mac_tmp, rr, mac_size); + rr->length -= mac_size; + } + else { - goto decryption_failed_or_bad_record_mac; + /* In this case there's no padding, so |rec->orig_len| + * equals |rec->length| and we checked that there's + * enough bytes for |mac_size| above. */ + rr->length -= mac_size; + mac = &rr->data[rr->length]; } + + i=s->method->ssl3_enc->mac(s,md,0 /* not send */); + if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) + enc_err = -1; + if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+mac_size) + enc_err = -1; + } + + if (enc_err < 0) + { + /* decryption failed, silently discard message */ + rr->length = 0; + s->packet_length = 0; + goto err; } /* r->length is now just compressed */ @@ -500,14 +530,6 @@ printf("\n"); dtls1_record_bitmap_update(s, &(s->d1->bitmap));/* Mark receipt of record. */ return(1); -decryption_failed_or_bad_record_mac: - /* Separate 'decryption_failed' alert was introduced with TLS 1.0, - * SSL 3.0 only has 'bad_record_mac'. But unless a decryption - * failure is directly visible from the ciphertext anyway, - * we should not reveal which kind of error occured -- this - * might become visible to an attacker (e.g. via logfile) */ - al=SSL_AD_BAD_RECORD_MAC; - SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); f_err: ssl3_send_alert(s,SSL3_AL_FATAL,al); err: @@ -526,22 +548,19 @@ err: /* used only by dtls1_read_bytes */ int dtls1_get_record(SSL *s) { - int ssl_major,ssl_minor,al; + int ssl_major,ssl_minor; int i,n; SSL3_RECORD *rr; - SSL_SESSION *sess; - unsigned char *p; + unsigned char *p = NULL; unsigned short version; DTLS1_BITMAP *bitmap; unsigned int is_next_epoch; rr= &(s->s3->rrec); - sess=s->session; /* The epoch may have changed. If so, process all the * pending records. This is a non-blocking operation. */ - if ( ! dtls1_process_buffered_records(s)) - return 0; + dtls1_process_buffered_records(s); /* if we're renegotiating, then there may be buffered records */ if (dtls1_get_processed_record(s)) @@ -557,12 +576,20 @@ again: /* read timeout is handled by dtls1_read_bytes */ if (n <= 0) return(n); /* error or non-blocking */ - OPENSSL_assert(s->packet_length == DTLS1_RT_HEADER_LENGTH); + /* this packet contained a partial record, dump it */ + if (s->packet_length != DTLS1_RT_HEADER_LENGTH) + { + s->packet_length = 0; + goto again; + } s->rstate=SSL_ST_READ_BODY; p=s->packet; + if (s->msg_callback) + s->msg_callback(0, 0, SSL3_RT_HEADER, p, DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg); + /* Pull apart the header into the DTLS1_RECORD */ rr->type= *(p++); ssl_major= *(p++); @@ -582,26 +609,27 @@ again: { if (version != s->version) { - SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); - /* Send back error using their - * version number :-) */ - s->version=version; - al=SSL_AD_PROTOCOL_VERSION; - goto f_err; + /* unexpected version, silently discard */ + rr->length = 0; + s->packet_length = 0; + goto again; } } - if ((version & 0xff00) != (DTLS1_VERSION & 0xff00)) + if ((version & 0xff00) != (s->version & 0xff00)) { - SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); - goto err; + /* wrong version, silently discard record */ + rr->length = 0; + s->packet_length = 0; + goto again; } if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) { - al=SSL_AD_RECORD_OVERFLOW; - SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG); - goto f_err; + /* record too long, silently discard it */ + rr->length = 0; + s->packet_length = 0; + goto again; } /* now s->rstate == SSL_ST_READ_BODY */ @@ -619,6 +647,7 @@ again: /* this packet contained a partial record, dump it */ if ( n != i) { + rr->length = 0; s->packet_length = 0; goto again; } @@ -632,44 +661,62 @@ again: bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch); if ( bitmap == NULL) { + rr->length = 0; s->packet_length = 0; /* dump this record */ goto again; /* get another record */ } - /* check whether this is a repeat, or aged record */ - if ( ! dtls1_record_replay_check(s, bitmap)) - { - rr->length = 0; - s->packet_length=0; /* dump this record */ - goto again; /* get another record */ - } +#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. + * Don't check if we're listening and this message is + * a ClientHello. They can look as if they're replayed, + * since they arrive from different connections and + * would be dropped unnecessarily. + */ + if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE && + *p == SSL3_MT_CLIENT_HELLO) && + !dtls1_record_replay_check(s, bitmap)) + { + rr->length = 0; + s->packet_length=0; /* dump this record */ + goto again; /* get another record */ + } +#ifndef OPENSSL_NO_SCTP + } +#endif /* just read a 0 length packet */ if (rr->length == 0) goto again; /* If this record is from the next epoch (either HM or ALERT), - * buffer it since it cannot be processed at this time. Records - * from the next epoch are marked as received even though they - * are not processed, so as to prevent any potential resource - * DoS attack */ + * and a handshake is currently in progress, buffer it since it + * cannot be processed at this time. However, do not buffer + * anything while listening. + */ if (is_next_epoch) { - dtls1_record_bitmap_update(s, bitmap); - dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num); + if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen) + { + dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num); + } + rr->length = 0; s->packet_length = 0; goto again; } - if ( ! dtls1_process_record(s)) - return(0); + if (!dtls1_process_record(s)) + { + rr->length = 0; + s->packet_length = 0; /* dump this record */ + goto again; /* get another record */ + } - dtls1_clear_timeouts(s); /* done waiting */ return(1); -f_err: - ssl3_send_alert(s,SSL3_AL_FATAL,al); -err: - return(0); } /* Return up to 'len' payload bytes received in 'type' records. @@ -725,7 +772,17 @@ int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) /* Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */ +#ifndef OPENSSL_NO_SCTP + /* Continue handshake if it had to be interrupted to read + * app data with SCTP. + */ + if ((!s->in_handshake && SSL_in_init(s)) || + (BIO_dgram_is_sctp(SSL_get_rbio(s)) && + (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK) && + s->s3->in_read_app_data != 2)) +#else if (!s->in_handshake && SSL_in_init(s)) +#endif { /* type == SSL3_RT_APPLICATION_DATA */ i=s->handshake_func(s); @@ -746,6 +803,36 @@ start: * s->s3->rrec.length, - number of bytes. */ rr = &(s->s3->rrec); + /* We are not handshaking and have no data yet, + * so process data buffered during the last handshake + * in advance, if any. + */ + if (s->state == SSL_ST_OK && rr->length == 0) + { + pitem *item; + item = pqueue_pop(s->d1->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 ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) { @@ -761,15 +848,26 @@ start: } } + if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE) + { + rr->length = 0; + goto start; + } + /* 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 */ && (rr->type != SSL3_RT_HANDSHAKE)) { - al=SSL_AD_UNEXPECTED_MESSAGE; - SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); - goto err; + /* 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. + */ + dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num); + rr->length = 0; + goto start; } /* If the other end has shut down, throw anything we read away @@ -812,6 +910,31 @@ start: rr->off=0; } } + +#ifndef OPENSSL_NO_SCTP + /* We were about to renegotiate but had to read + * belated application data first, so retry. + */ + if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && + rr->type == SSL3_RT_APPLICATION_DATA && + (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)) + { + s->rwstate=SSL_READING; + BIO_clear_retry_flags(SSL_get_rbio(s)); + BIO_set_retry_read(SSL_get_rbio(s)); + } + + /* 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); } @@ -839,15 +962,41 @@ start: dest = s->d1->alert_fragment; dest_len = &s->d1->alert_fragment_len; } - /* else it's a CCS message, or it's wrong */ - else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC) - { - /* 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; - } +#ifndef OPENSSL_NO_HEARTBEATS + else if (rr->type == TLS1_RT_HEARTBEAT) + { + dtls1_process_heartbeat(s); + /* Exit and notify application to read again */ + rr->length = 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 (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC) + { + /* Application data while renegotiating + * is allowed. Try again reading. + */ + if (rr->type == 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) { @@ -909,6 +1058,7 @@ start: !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && !s->s3->renegotiate) { + s->new_session = 1; ssl3_renegotiate(s); if (ssl3_renegotiate_check(s)) { @@ -970,6 +1120,21 @@ start: s->s3->warn_alert = alert_descr; 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); } @@ -985,7 +1150,9 @@ start: n2s(p, seq); n2l3(p, frag_off); - dtls1_retransmit_message(s, seq, frag_off, &found); + 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)); */ @@ -1030,13 +1197,17 @@ start: if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) { struct ccs_header_st ccs_hdr; + unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH; dtls1_get_ccs_header(rr->data, &ccs_hdr); + if (s->version == DTLS1_BAD_VER) + ccs_hdr_len = 3; + /* 'Change Cipher Spec' is just a single byte, so we know * exactly what the record payload has to look like */ /* XDTLS: check that epoch is consistent */ - if ( (rr->length != DTLS1_CCS_HEADER_LENGTH) || + if ( (rr->length != ccs_hdr_len) || (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS)) { i=SSL_AD_ILLEGAL_PARAMETER; @@ -1050,6 +1221,16 @@ start: s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg); + /* We can't process a CCS now, because previous handshake + * messages are still missing, so just drop it. + */ + if (!s->d1->change_cipher_spec_ok) + { + goto start; + } + + s->d1->change_cipher_spec_ok = 0; + s->s3->change_cipher_spec=1; if (!ssl3_do_change_cipher_spec(s)) goto err; @@ -1057,6 +1238,18 @@ start: /* do this whenever CCS is processed */ dtls1_reset_seq_numbers(s, SSL3_CC_READ); + if (s->version == DTLS1_BAD_VER) + s->d1->handshake_read_seq++; + +#ifndef OPENSSL_NO_SCTP + /* Remember that a CCS has been received, + * so that an old key of SCTP-Auth can be + * deleted when a CCS is sent. Will be ignored + * if no SCTP is used + */ + BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL); +#endif + goto start; } @@ -1074,6 +1267,19 @@ start: 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); + rr->length = 0; + goto start; + } + if (((s->state&SSL_ST_MASK) == SSL_ST_OK) && !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) { @@ -1086,6 +1292,7 @@ start: #else s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; #endif + s->renegotiate=1; s->new_session=1; } i=s->handshake_func(s); @@ -1180,10 +1387,18 @@ err: int dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len) { - unsigned int n,tot; int i; - if (SSL_in_init(s) && !s->in_handshake) +#ifndef OPENSSL_NO_SCTP + /* Check if we have to continue an interrupted handshake + * for reading belated app data with SCTP. + */ + if ((SSL_in_init(s) && !s->in_handshake) || + (BIO_dgram_is_sctp(SSL_get_wbio(s)) && + (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK))) +#else + if (SSL_in_init(s) && !s->in_handshake) +#endif { i=s->handshake_func(s); if (i < 0) return(i); @@ -1194,31 +1409,14 @@ dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len) } } - tot = s->s3->wnum; - n = len - tot; - - while( n) + if (len > SSL3_RT_MAX_PLAIN_LENGTH) { - /* dtls1_write_bytes sends one record at a time, sized according to - * the currently known MTU */ - i = dtls1_write_bytes(s, type, buf_, len); - if (i <= 0) return i; - - if ((i == (int)n) || - (type == SSL3_RT_APPLICATION_DATA && - (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) - { - /* next chunk of data should get another prepended empty fragment - * in ciphersuites with known-IV weakness: */ - s->s3->empty_fragment_done = 0; - return tot+i; - } - - tot += i; - n-=i; + SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_DTLS_MESSAGE_TOO_BIG); + return -1; } - return tot; + i = dtls1_write_bytes(s, type, buf_, len); + return i; } @@ -1259,46 +1457,13 @@ have_handshake_fragment(SSL *s, int type, unsigned char *buf, /* 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 dtls1_write_bytes(SSL *s, int type, const void *buf, int len) { - const unsigned char *buf=buf_; - unsigned int tot,n,nw; int i; - unsigned int mtu; + OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH); s->rwstate=SSL_NOTHING; - tot=s->s3->wnum; - - n=(len-tot); - - /* handshake layer figures out MTU for itself, but data records - * are also sent through this interface, so need to figure out MTU */ -#if 0 - mtu = BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_GET_MTU, 0, NULL); - mtu += DTLS1_HM_HEADER_LENGTH; /* HM already inserted */ -#endif - mtu = s->d1->mtu; - - if (mtu > SSL3_RT_MAX_PLAIN_LENGTH) - mtu = SSL3_RT_MAX_PLAIN_LENGTH; - - if (n > mtu) - nw=mtu; - else - nw=n; - - i=do_dtls1_write(s, type, &(buf[tot]), nw, 0); - if (i <= 0) - { - s->s3->wnum=tot; - return i; - } - - if ( (int)s->s3->wnum + i == len) - s->s3->wnum = 0; - else - s->s3->wnum += i; - + i=do_dtls1_write(s, type, buf, len, 0); return i; } @@ -1307,10 +1472,10 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, 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; - int bs; /* first check if there is a SSL3_BUFFER still being written * out. This will happen with non blocking IO */ @@ -1354,7 +1519,7 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, #if 0 /* 'create_empty_fragment' is true only when this function calls itself */ if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done - && SSL_version(s) != DTLS1_VERSION) + && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) { /* countermeasure against known-IV weakness in CBC ciphersuites * (see http://www.openssl.org/~bodo/tls-cbc.txt) @@ -1381,33 +1546,54 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, s->s3->empty_fragment_done = 1; } #endif - p = wb->buf + prefix_len; /* write the header */ *(p++)=type&0xff; wr->type=type; - - *(p++)=(s->version>>8); - *(p++)=s->version&0xff; + /* 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->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B + && s->method->version == DTLS_ANY_VERSION + && s->client_version == DTLS1_VERSION) + { + *(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; - /* lets setup the record stuff. */ - - /* Make space for the explicit IV in case of CBC. - * (this is a bit of a boundary violation, but what the heck). - */ - if ( s->enc_write_ctx && - (EVP_CIPHER_mode( s->enc_write_ctx->cipher ) & EVP_CIPH_CBC_MODE)) - bs = EVP_CIPHER_block_size(s->enc_write_ctx->cipher); - else - bs = 0; + /* 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 + eivlen = 0; + } + else + eivlen = 0; - wr->data=p + bs; /* make room for IV in case of CBC */ + /* lets setup the record stuff. */ + wr->data=p + eivlen; /* make room for IV in case of CBC */ wr->length=(int)len; wr->input=(unsigned char *)buf; @@ -1435,7 +1621,7 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, if (mac_size != 0) { - if(s->method->ssl3_enc->mac(s,&(p[wr->length + bs]),1) < 0) + if(s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0) goto err; wr->length+=mac_size; } @@ -1444,15 +1630,8 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, wr->input=p; wr->data=p; - - /* ssl3_enc can only have an error on read */ - if (bs) /* bs != 0 in case of CBC */ - { - RAND_pseudo_bytes(p,bs); - /* master IV and last CBC residue stand for - * the rest of randomness */ - wr->length += bs; - } + if (eivlen) + wr->length += eivlen; s->method->ssl3_enc->enc(s,1); @@ -1472,6 +1651,9 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, pseq+=6; s2n(wr->length,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 */ @@ -1728,15 +1910,9 @@ dtls1_reset_seq_numbers(SSL *s, int rw) else { seq = s->s3->write_sequence; + memcpy(s->d1->last_write_sequence, seq, sizeof(s->s3->write_sequence)); s->d1->w_epoch++; } memset(seq, 0x00, seq_bytes); } - - -static void -dtls1_clear_timeouts(SSL *s) - { - memset(&(s->d1->timeout), 0x00, sizeof(struct dtls1_timeout_st)); - }