diff options
Diffstat (limited to 'openssl/ssl/d1_pkt.c')
| -rw-r--r-- | openssl/ssl/d1_pkt.c | 3537 |
1 files changed, 1769 insertions, 1768 deletions
diff --git a/openssl/ssl/d1_pkt.c b/openssl/ssl/d1_pkt.c index 1fd58bf59..79b723a5e 100644 --- a/openssl/ssl/d1_pkt.c +++ b/openssl/ssl/d1_pkt.c @@ -1,1768 +1,1769 @@ -/* ssl/d1_pkt.c */ -/* - * DTLS implementation written by Nagendra Modadugu - * (nagendra@cs.stanford.edu) for the OpenSSL project 2005. - */ -/* ==================================================================== - * Copyright (c) 1998-2005 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). - * - */ -/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) - * All rights reserved. - * - * This package is an SSL implementation written - * by Eric Young (eay@cryptsoft.com). - * The implementation was written so as to conform with Netscapes SSL. - * - * This library is free for commercial and non-commercial use as long as - * the following conditions are aheared to. The following conditions - * apply to all code found in this distribution, be it the RC4, RSA, - * lhash, DES, etc., code; not just the SSL code. The SSL documentation - * included with this distribution is covered by the same copyright terms - * except that the holder is Tim Hudson (tjh@cryptsoft.com). - * - * Copyright remains Eric Young's, and as such any Copyright notices in - * the code are not to be removed. - * If this package is used in a product, Eric Young should be given attribution - * as the author of the parts of the library used. - * This can be in the form of a textual message at program startup or - * in documentation (online or textual) provided with the package. - * - * 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 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 acknowledgement: - * "This product includes cryptographic software written by - * Eric Young (eay@cryptsoft.com)" - * The word 'cryptographic' can be left out if the rouines from the library - * being used are not cryptographic related :-). - * 4. If you include any Windows specific code (or a derivative thereof) from - * the apps directory (application code) you must include an acknowledgement: - * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" - * - * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND - * ANY EXPRESS 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 AUTHOR OR 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. - * - * The licence and distribution terms for any publically available version or - * derivative of this code cannot be changed. i.e. this code cannot simply be - * copied and put under another distribution licence - * [including the GNU Public Licence.] - */ - -#include <stdio.h> -#include <errno.h> -#define USE_SOCKETS -#include "ssl_locl.h" -#include <openssl/evp.h> -#include <openssl/buffer.h> -#include <openssl/pqueue.h> -#include <openssl/rand.h> - -/* mod 128 saturating subtract of two 64-bit values in big-endian order */ -static int satsub64be(const unsigned char *v1,const unsigned char *v2) -{ int ret,sat,brw,i; - - if (sizeof(long) == 8) do - { const union { long one; char little; } is_endian = {1}; - long l; - - if (is_endian.little) break; - /* not reached on little-endians */ - /* following test is redundant, because input is - * always aligned, but I take no chances... */ - if (((size_t)v1|(size_t)v2)&0x7) break; - - l = *((long *)v1); - l -= *((long *)v2); - if (l>128) return 128; - else if (l<-128) return -128; - else return (int)l; - } while (0); - - ret = (int)v1[7]-(int)v2[7]; - sat = 0; - brw = ret>>8; /* brw is either 0 or -1 */ - if (ret & 0x80) - { for (i=6;i>=0;i--) - { brw += (int)v1[i]-(int)v2[i]; - sat |= ~brw; - brw >>= 8; - } - } - else - { for (i=6;i>=0;i--) - { brw += (int)v1[i]-(int)v2[i]; - sat |= brw; - brw >>= 8; - } - } - brw <<= 8; /* brw is either 0 or -256 */ - - if (sat&0xff) return brw | 0x80; - else return brw + (ret&0xFF); -} - -static int have_handshake_fragment(SSL *s, int type, unsigned char *buf, - int len, int peek); -static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap); -static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap); -static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, - unsigned int *is_next_epoch); -#if 0 -static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, - unsigned short *priority, unsigned long *offset); -#endif -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 -dtls1_copy_record(SSL *s, pitem *item) - { - DTLS1_RECORD_DATA *rdata; - - rdata = (DTLS1_RECORD_DATA *)item->data; - - if (s->s3->rbuf.buf != NULL) - OPENSSL_free(s->s3->rbuf.buf); - - s->packet = rdata->packet; - 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); - } - - -static 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(DTLS1_RECORD_DATA)); - item = pitem_new(priority, rdata); - if (rdata == NULL || item == NULL) - { - if (rdata != NULL) OPENSSL_free(rdata); - if (item != NULL) pitem_free(item); - - SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR); - return(0); - } - - rdata->packet = s->packet; - rdata->packet_length = s->packet_length; - memcpy(&(rdata->rbuf), &(s->s3->rbuf), sizeof(SSL3_BUFFER)); - memcpy(&(rdata->rrec), &(s->s3->rrec), sizeof(SSL3_RECORD)); - - item->data = rdata; - - /* insert should not fail, since duplicates are dropped */ - if (pqueue_insert(queue->q, item) == NULL) - { - OPENSSL_free(rdata); - pitem_free(item); - return(0); - } - - s->packet = NULL; - s->packet_length = 0; - memset(&(s->s3->rbuf), 0, sizeof(SSL3_BUFFER)); - memset(&(s->s3->rrec), 0, sizeof(SSL3_RECORD)); - - if (!ssl3_setup_buffers(s)) - { - SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR); - OPENSSL_free(rdata); - pitem_free(item); - return(0); - } - - return(1); - } - - -static 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)->d1->unprocessed_rcds)) - -/* retrieve a buffered record that belongs to the current epoch, ie, processed */ -#define dtls1_get_processed_record(s) \ - dtls1_retrieve_buffered_record((s), \ - &((s)->d1->processed_rcds)) - -static int -dtls1_process_buffered_records(SSL *s) - { - pitem *item; - - item = pqueue_peek(s->d1->unprocessed_rcds.q); - if (item) - { - /* Check if epoch is current. */ - if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch) - return(1); /* Nothing to do. */ - - /* Process all the records. */ - while (pqueue_peek(s->d1->unprocessed_rcds.q)) - { - dtls1_get_unprocessed_record(s); - if ( ! dtls1_process_record(s)) - return(0); - dtls1_buffer_record(s, &(s->d1->processed_rcds), - s->s3->rrec.seq_num); - } - } - - /* sync epoch numbers once all the unprocessed records - * have been processed */ - s->d1->processed_rcds.epoch = s->d1->r_epoch; - s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1; - - return(1); - } - - -#if 0 - -static int -dtls1_get_buffered_record(SSL *s) - { - pitem *item; - PQ_64BIT priority = - (((PQ_64BIT)s->d1->handshake_read_seq) << 32) | - ((PQ_64BIT)s->d1->r_msg_hdr.frag_off); - - if ( ! SSL_in_init(s)) /* if we're not (re)negotiating, - nothing buffered */ - return 0; - - - item = pqueue_peek(s->d1->rcvd_records); - if (item && item->priority == priority) - { - /* Check if we've received the record of interest. It must be - * a handshake record, since data records as passed up without - * buffering */ - DTLS1_RECORD_DATA *rdata; - item = pqueue_pop(s->d1->rcvd_records); - rdata = (DTLS1_RECORD_DATA *)item->data; - - if (s->s3->rbuf.buf != NULL) - OPENSSL_free(s->s3->rbuf.buf); - - s->packet = rdata->packet; - s->packet_length = rdata->packet_length; - memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER)); - memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD)); - - OPENSSL_free(item->data); - pitem_free(item); - - /* s->d1->next_expected_seq_num++; */ - return(1); - } - - return 0; - } - -#endif - -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; - - /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, - * and we have that many bytes in s->packet - */ - rr->input= &(s->packet[DTLS1_RT_HEADER_LENGTH]); - - /* ok, we can now read from 's->packet' data into 'rr' - * rr->input points at rr->length bytes, which - * need to be copied into rr->data by either - * the decryption or by the decompression - * When the data is 'copied' into the rr->data buffer, - * rr->input will be pointed at the new buffer */ - - /* We now have - encrypted [ MAC [ compressed [ plain ] ] ] - * rr->length bytes of encrypted compressed stuff. */ - - /* check is not needed I believe */ - if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) - { - al=SSL_AD_RECORD_OVERFLOW; - SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG); - goto f_err; - } - - /* decrypt in place in 'rr->input' */ - rr->data=rr->input; - - enc_err = s->method->ssl3_enc->enc(s,0); - if (enc_err <= 0) - { - if (enc_err == 0) - /* SSLerr() and ssl3_send_alert() have been called */ - goto err; - - /* otherwise enc_err == -1 */ - goto err; - } - -#ifdef TLS_DEBUG -printf("dec %d\n",rr->length); -{ unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); } -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) - { - /* !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 err; -#endif - } - /* check the MAC for rr->input (it's in mac_size bytes at the tail) */ - if (rr->length < mac_size) - { -#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 err; -#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) - { - goto err; - } - } - - /* r->length is now just compressed */ - if (s->expand != NULL) - { - if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) - { - al=SSL_AD_RECORD_OVERFLOW; - SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG); - goto f_err; - } - if (!ssl3_do_uncompress(s)) - { - al=SSL_AD_DECOMPRESSION_FAILURE; - SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_BAD_DECOMPRESSION); - goto f_err; - } - } - - if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH) - { - al=SSL_AD_RECORD_OVERFLOW; - SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DATA_LENGTH_TOO_LONG); - goto f_err; - } - - rr->off=0; - /* So at this point the following is true - * ssl->s3->rrec.type is the type of record - * ssl->s3->rrec.length == number of bytes in record - * ssl->s3->rrec.off == offset to first valid byte - * ssl->s3->rrec.data == where to take bytes from, increment - * after use :-). - */ - - /* we have pulled in a full packet so zero things */ - s->packet_length=0; - dtls1_record_bitmap_update(s, &(s->d1->bitmap));/* Mark receipt of record. */ - return(1); - -f_err: - ssl3_send_alert(s,SSL3_AL_FATAL,al); -err: - return(0); -} - - -/* Call this to get a new input record. - * It will return <= 0 if more data is needed, normally due to an error - * or non-blocking IO. - * When it finishes, one packet has been decoded and can be found in - * ssl->s3->rrec.type - is the type of record - * ssl->s3->rrec.data, - data - * ssl->s3->rrec.length, - number of bytes - */ -/* used only by dtls1_read_bytes */ -int dtls1_get_record(SSL *s) - { - int ssl_major,ssl_minor; - int i,n; - SSL3_RECORD *rr; - unsigned char *p = NULL; - unsigned short version; - DTLS1_BITMAP *bitmap; - unsigned int is_next_epoch; - - rr= &(s->s3->rrec); - - /* The epoch may have changed. If so, process all the - * pending records. This is a non-blocking operation. */ - dtls1_process_buffered_records(s); - - /* if we're renegotiating, then there may be buffered records */ - if (dtls1_get_processed_record(s)) - return 1; - - /* get something from the wire */ -again: - /* check if we have the header */ - if ( (s->rstate != SSL_ST_READ_BODY) || - (s->packet_length < DTLS1_RT_HEADER_LENGTH)) - { - n=ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); - /* read timeout is handled by dtls1_read_bytes */ - if (n <= 0) return(n); /* error or non-blocking */ - - /* 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; - - /* Pull apart the header into the DTLS1_RECORD */ - rr->type= *(p++); - ssl_major= *(p++); - ssl_minor= *(p++); - version=(ssl_major<<8)|ssl_minor; - - /* sequence number is 64 bits, with top 2 bytes = epoch */ - n2s(p,rr->epoch); - - memcpy(&(s->s3->read_sequence[2]), p, 6); - p+=6; - - n2s(p,rr->length); - - /* Lets check version */ - if (!s->first_packet) - { - if (version != s->version) - { - /* unexpected version, silently discard */ - rr->length = 0; - s->packet_length = 0; - goto again; - } - } - - if ((version & 0xff00) != (s->version & 0xff00)) - { - /* wrong version, silently discard record */ - rr->length = 0; - s->packet_length = 0; - goto again; - } - - if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) - { - /* record too long, silently discard it */ - rr->length = 0; - s->packet_length = 0; - goto again; - } - - /* now s->rstate == SSL_ST_READ_BODY */ - } - - /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ - - if (rr->length > s->packet_length-DTLS1_RT_HEADER_LENGTH) - { - /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */ - i=rr->length; - n=ssl3_read_n(s,i,i,1); - if (n <= 0) return(n); /* error or non-blocking io */ - - /* this packet contained a partial record, dump it */ - if ( n != i) - { - rr->length = 0; - s->packet_length = 0; - goto again; - } - - /* now n == rr->length, - * and s->packet_length == DTLS1_RT_HEADER_LENGTH + rr->length */ - } - s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */ - - /* match epochs. NULL means the packet is dropped on the floor */ - 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. - * 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 */ - } - - /* just read a 0 length packet */ - if (rr->length == 0) goto again; - - /* If this record is from the next epoch (either HM or ALERT), - * and a handshake is currently in progress, buffer it since it - * cannot be processed at this time. */ - if (is_next_epoch) - { - if (SSL_in_init(s) || s->in_handshake) - { - 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)) - { - rr->length = 0; - s->packet_length = 0; /* dump this record */ - goto again; /* get another record */ - } - - dtls1_clear_timeouts(s); /* done waiting */ - 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), ChangeCipherSpec records (not really - * a surprise, but handled as if it were), or renegotiation requests. - * 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, 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 (s->s3->rbuf.buf == NULL) /* Not initialized yet */ - if (!ssl3_setup_buffers(s)) - return(-1); - - /* XXX: check what the second '&& type' is about */ - if ((type && (type != SSL3_RT_APPLICATION_DATA) && - (type != SSL3_RT_HANDSHAKE) && type) || - (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, peek))) - return ret; - - /* Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */ - - if (!s->in_handshake && 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->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) - { - 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)) - { - 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; - } - } - - /* 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)) - { - /* 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 - * (even in 'peek' mode) */ - if (s->shutdown & SSL_RECEIVED_SHUTDOWN) - { - rr->length=0; - s->rwstate=SSL_NOTHING; - return(0); - } - - - if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */ - { - /* 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 (len <= 0) return(len); - - if ((unsigned int)len > rr->length) - n = rr->length; - else - n = (unsigned int)len; - - memcpy(buf,&(rr->data[rr->off]),n); - if (!peek) - { - rr->length-=n; - rr->off+=n; - if (rr->length == 0) - { - s->rstate=SSL_ST_READ_HEADER; - rr->off=0; - } - } - 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 (rr->type == SSL3_RT_HANDSHAKE) - { - dest_maxlen = sizeof s->d1->handshake_fragment; - dest = s->d1->handshake_fragment; - dest_len = &s->d1->handshake_fragment_len; - } - else if (rr->type == SSL3_RT_ALERT) - { - dest_maxlen = sizeof(s->d1->alert_fragment); - dest = s->d1->alert_fragment; - dest_len = &s->d1->alert_fragment_len; - } - /* 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) - { - /* XDTLS: In a pathalogical case, the Client Hello - * may be fragmented--don't always expect dest_maxlen bytes */ - if ( rr->length < 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->rstate=SSL_ST_READ_HEADER; - rr->length = 0; - goto start; - } - - /* now move 'n' bytes: */ - for ( k = 0; k < dest_maxlen; k++) - { - dest[k] = rr->data[rr->off++]; - rr->length--; - } - *dest_len = dest_maxlen; - } - } - - /* s->d1->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE; - * s->d1->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->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) && - (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && - (s->session != NULL) && (s->session->cipher != NULL)) - { - s->d1->handshake_fragment_len = 0; - - if ((s->d1->handshake_fragment[1] != 0) || - (s->d1->handshake_fragment[2] != 0) || - (s->d1->handshake_fragment[3] != 0)) - { - al=SSL_AD_DECODE_ERROR; - SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_HELLO_REQUEST); - goto 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->d1->handshake_fragment, 4, s, s->msg_callback_arg); - - if (SSL_is_init_finished(s) && - !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && - !s->s3->renegotiate) - { - 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 (s->s3->rbuf.left == 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); - } - } - } - } - /* we either finished a handshake or ignored the request, - * now try again to obtain the (application) data we were asked for */ - goto start; - } - - if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) - { - int alert_level = s->d1->alert_fragment[0]; - int alert_descr = s->d1->alert_fragment[1]; - - s->d1->alert_fragment_len = 0; - - if (s->msg_callback) - s->msg_callback(0, s->version, SSL3_RT_ALERT, - s->d1->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 == 1) /* warning */ - { - s->s3->warn_alert = alert_descr; - if (alert_descr == SSL_AD_CLOSE_NOTIFY) - { - 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->d1->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 == 2) /* 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->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; - rr->length=0; - return(0); - } - - 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 != ccs_hdr_len) || - (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS)) - { - i=SSL_AD_ILLEGAL_PARAMETER; - SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC); - goto err; - } - - rr->length=0; - - if (s->msg_callback) - 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; - - /* 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++; - - goto start; - } - - /* Unexpected handshake message (Client Hello, or protocol violation) */ - if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) && - !s->in_handshake) - { - struct hm_header_st msg_hdr; - - /* this may just be a stale retransmit */ - dtls1_get_message_header(rr->data, &msg_hdr); - if( rr->epoch != s->d1->r_epoch) - { - rr->length = 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) - { - 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)) - { -#if 0 /* worked only because C operator preferences are not as expected (and - * because this is not really needed for clients except for detecting - * protocol violations): */ - s->state=SSL_ST_BEFORE|(s->server) - ?SSL_ST_ACCEPT - :SSL_ST_CONNECT; -#else - s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; -#endif - 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 (s->s3->rbuf.left == 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 (rr->type) - { - default: -#ifndef OPENSSL_NO_TLS - /* TLS just ignores unknown message types */ - if (s->version == TLS1_VERSION) - { - rr->length = 0; - goto start; - } -#endif - 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 s->in_handshake is set, 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) && - (( - (s->state & SSL_ST_CONNECT) && - (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && - (s->state <= SSL3_ST_CR_SRVR_HELLO_A) - ) || ( - (s->state & SSL_ST_ACCEPT) && - (s->state <= SSL3_ST_SW_HELLO_REQ_A) && - (s->state >= SSL3_ST_SR_CLNT_HELLO_A) - ) - )) - { - 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); -err: - return(-1); - } - -int -dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len) - { - int i; - - if (SSL_in_init(s) && !s->in_handshake) - { - i=s->handshake_func(s); - if (i < 0) return(i); - if (i == 0) - { - SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); - return -1; - } - } - - if (len > SSL3_RT_MAX_PLAIN_LENGTH) - { - SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_DTLS_MESSAGE_TOO_BIG); - return -1; - } - - i = dtls1_write_bytes(s, type, buf_, len); - return i; - } - - - /* 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, int peek) - { - - if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0)) - /* (partially) satisfy request from storage */ - { - unsigned char *src = s->d1->handshake_fragment; - unsigned char *dst = buf; - unsigned int k,n; - - /* peek == 0 */ - n = 0; - while ((len > 0) && (s->d1->handshake_fragment_len > 0)) - { - *dst++ = *src++; - len--; s->d1->handshake_fragment_len--; - n++; - } - /* move any remaining fragment bytes: */ - for (k = 0; k < s->d1->handshake_fragment_len; k++) - s->d1->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; - 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 */ - if (s->s3->wbuf.left != 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; - - wr= &(s->s3->wrec); - wb= &(s->s3->wbuf); - 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; - } - - /* DTLS implements explicit IV, so no need for empty fragments */ -#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_BAD_VER) - { - /* countermeasure against known-IV weakness in CBC ciphersuites - * (see http://www.openssl.org/~bodo/tls-cbc.txt) - */ - - if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) - { - /* recursive function call with 'create_empty_fragment' set; - * this prepares and buffers the data for an empty fragment - * (these 'prefix_len' bytes are sent out later - * together with the actual payload) */ - prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1); - if (prefix_len <= 0) - goto err; - - if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE) - { - /* insufficient space */ - SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR); - goto err; - } - } - - 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; - - /* 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; - - wr->data=p + bs; /* make room for IV in case of CBC */ - wr->length=(int)len; - wr->input=(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)) - { - SSLerr(SSL_F_DO_DTLS1_WRITE,SSL_R_COMPRESSION_FAILURE); - goto err; - } - } - else - { - memcpy(wr->data,wr->input,wr->length); - wr->input=wr->data; - } - - /* 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,&(p[wr->length + bs]),1) < 0) - goto err; - wr->length+=mac_size; - } - - /* this is true regardless of mac size */ - 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; - } - - s->method->ssl3_enc->enc(s,1); - - /* 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->d1->w_epoch, pseq); - - /* XDTLS: ?? */ -/* else - s2n(s->d1->handshake_epoch, pseq); */ - - memcpy(pseq, &(s->s3->write_sequence[2]), 6); - pseq+=6; - s2n(wr->length,pseq); - - /* we should now have - * wr->data pointing to the encrypted data, which is - * wr->length long */ - wr->type=type; /* not needed but helps for debugging */ - wr->length+=DTLS1_RT_HEADER_LENGTH; - -#if 0 /* this is now done at the message layer */ - /* buffer the record, making it easy to handle retransmits */ - if ( type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC) - dtls1_buffer_record(s, wr->data, wr->length, - *((PQ_64BIT *)&(s->s3->write_sequence[0]))); -#endif - - ssl3_record_sequence_update(&(s->s3->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 */ - wb->left = prefix_len + wr->length; - wb->offset = 0; - - /* memorize arguments so that ssl3_write_pending can detect bad write retries later */ - s->s3->wpend_tot=len; - s->s3->wpend_buf=buf; - s->s3->wpend_type=type; - s->s3->wpend_ret=len; - - /* we now just need to write the buffer */ - return ssl3_write_pending(s,type,buf,len); -err: - return -1; - } - - - -static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap) - { - int cmp; - unsigned int shift; - const unsigned char *seq = s->s3->read_sequence; - - cmp = satsub64be(seq,bitmap->max_seq_num); - if (cmp > 0) - { - memcpy (s->s3->rrec.seq_num,seq,8); - return 1; /* this record in new */ - } - shift = -cmp; - if (shift >= sizeof(bitmap->map)*8) - return 0; /* stale, outside the window */ - else if (bitmap->map & (1UL<<shift)) - return 0; /* record previously received */ - - memcpy (s->s3->rrec.seq_num,seq,8); - return 1; - } - - -static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap) - { - int cmp; - unsigned int shift; - const unsigned char *seq = s->s3->read_sequence; - - cmp = satsub64be(seq,bitmap->max_seq_num); - if (cmp > 0) - { - shift = cmp; - if (shift < sizeof(bitmap->map)*8) - bitmap->map <<= shift, bitmap->map |= 1UL; - else - bitmap->map = 1UL; - memcpy(bitmap->max_seq_num,seq,8); - } - else { - shift = -cmp; - if (shift < sizeof(bitmap->map)*8) - bitmap->map |= 1UL<<shift; - } - } - - -int dtls1_dispatch_alert(SSL *s) - { - int i,j; - void (*cb)(const SSL *ssl,int type,int val)=NULL; - unsigned char buf[DTLS1_AL_HEADER_LENGTH]; - unsigned char *ptr = &buf[0]; - - s->s3->alert_dispatch=0; - - memset(buf, 0x00, sizeof(buf)); - *ptr++ = s->s3->send_alert[0]; - *ptr++ = s->s3->send_alert[1]; - -#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE - if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) - { - s2n(s->d1->handshake_read_seq, ptr); -#if 0 - if ( s->d1->r_msg_hdr.frag_off == 0) /* waiting for a new msg */ - - else - s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */ -#endif - -#if 0 - fprintf(stderr, "s->d1->handshake_read_seq = %d, s->d1->r_msg_hdr.seq = %d\n",s->d1->handshake_read_seq,s->d1->r_msg_hdr.seq); -#endif - l2n3(s->d1->r_msg_hdr.frag_off, ptr); - } -#endif - - i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0); - if (i <= 0) - { - s->s3->alert_dispatch=1; - /* fprintf( stderr, "not done with alert\n" ); */ - } - else - { - if (s->s3->send_alert[0] == SSL3_AL_FATAL -#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE - || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE -#endif - ) - (void)BIO_flush(s->wbio); - - if (s->msg_callback) - s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, - 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=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1]; - cb(s,SSL_CB_WRITE_ALERT,j); - } - } - return(i); - } - - -static 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->d1->r_epoch) - return &s->d1->bitmap; - - /* Only HM and ALERT messages can be from the next epoch */ - else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) && - (rr->type == SSL3_RT_HANDSHAKE || - rr->type == SSL3_RT_ALERT)) - { - *is_next_epoch = 1; - return &s->d1->next_bitmap; - } - - return NULL; - } - -#if 0 -static int -dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, unsigned short *priority, - unsigned long *offset) - { - - /* alerts are passed up immediately */ - if ( rr->type == SSL3_RT_APPLICATION_DATA || - rr->type == SSL3_RT_ALERT) - return 0; - - /* Only need to buffer if a handshake is underway. - * (this implies that Hello Request and Client Hello are passed up - * immediately) */ - if ( SSL_in_init(s)) - { - unsigned char *data = rr->data; - /* need to extract the HM/CCS sequence number here */ - if ( rr->type == SSL3_RT_HANDSHAKE || - rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) - { - unsigned short seq_num; - struct hm_header_st msg_hdr; - struct ccs_header_st ccs_hdr; - - if ( rr->type == SSL3_RT_HANDSHAKE) - { - dtls1_get_message_header(data, &msg_hdr); - seq_num = msg_hdr.seq; - *offset = msg_hdr.frag_off; - } - else - { - dtls1_get_ccs_header(data, &ccs_hdr); - seq_num = ccs_hdr.seq; - *offset = 0; - } - - /* this is either a record we're waiting for, or a - * retransmit of something we happened to previously - * receive (higher layers will drop the repeat silently */ - if ( seq_num < s->d1->handshake_read_seq) - return 0; - if (rr->type == SSL3_RT_HANDSHAKE && - seq_num == s->d1->handshake_read_seq && - msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off) - return 0; - else if ( seq_num == s->d1->handshake_read_seq && - (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC || - msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off)) - return 0; - else - { - *priority = seq_num; - return 1; - } - } - else /* unknown record type */ - return 0; - } - - return 0; - } -#endif - -void -dtls1_reset_seq_numbers(SSL *s, int rw) - { - unsigned char *seq; - unsigned int seq_bytes = sizeof(s->s3->read_sequence); - - if ( rw & SSL3_CC_READ) - { - seq = s->s3->read_sequence; - s->d1->r_epoch++; - memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP)); - memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP)); - } - 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)); - } +/* ssl/d1_pkt.c */
+/*
+ * DTLS implementation written by Nagendra Modadugu
+ * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
+ */
+/* ====================================================================
+ * Copyright (c) 1998-2005 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).
+ *
+ */
+/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
+ * All rights reserved.
+ *
+ * This package is an SSL implementation written
+ * by Eric Young (eay@cryptsoft.com).
+ * The implementation was written so as to conform with Netscapes SSL.
+ *
+ * This library is free for commercial and non-commercial use as long as
+ * the following conditions are aheared to. The following conditions
+ * apply to all code found in this distribution, be it the RC4, RSA,
+ * lhash, DES, etc., code; not just the SSL code. The SSL documentation
+ * included with this distribution is covered by the same copyright terms
+ * except that the holder is Tim Hudson (tjh@cryptsoft.com).
+ *
+ * Copyright remains Eric Young's, and as such any Copyright notices in
+ * the code are not to be removed.
+ * If this package is used in a product, Eric Young should be given attribution
+ * as the author of the parts of the library used.
+ * This can be in the form of a textual message at program startup or
+ * in documentation (online or textual) provided with the package.
+ *
+ * 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 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 acknowledgement:
+ * "This product includes cryptographic software written by
+ * Eric Young (eay@cryptsoft.com)"
+ * The word 'cryptographic' can be left out if the rouines from the library
+ * being used are not cryptographic related :-).
+ * 4. If you include any Windows specific code (or a derivative thereof) from
+ * the apps directory (application code) you must include an acknowledgement:
+ * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
+ * ANY EXPRESS 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 AUTHOR OR 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.
+ *
+ * The licence and distribution terms for any publically available version or
+ * derivative of this code cannot be changed. i.e. this code cannot simply be
+ * copied and put under another distribution licence
+ * [including the GNU Public Licence.]
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#define USE_SOCKETS
+#include "ssl_locl.h"
+#include <openssl/evp.h>
+#include <openssl/buffer.h>
+#include <openssl/pqueue.h>
+#include <openssl/rand.h>
+
+/* mod 128 saturating subtract of two 64-bit values in big-endian order */
+static int satsub64be(const unsigned char *v1,const unsigned char *v2)
+{ int ret,sat,brw,i;
+
+ if (sizeof(long) == 8) do
+ { const union { long one; char little; } is_endian = {1};
+ long l;
+
+ if (is_endian.little) break;
+ /* not reached on little-endians */
+ /* following test is redundant, because input is
+ * always aligned, but I take no chances... */
+ if (((size_t)v1|(size_t)v2)&0x7) break;
+
+ l = *((long *)v1);
+ l -= *((long *)v2);
+ if (l>128) return 128;
+ else if (l<-128) return -128;
+ else return (int)l;
+ } while (0);
+
+ ret = (int)v1[7]-(int)v2[7];
+ sat = 0;
+ brw = ret>>8; /* brw is either 0 or -1 */
+ if (ret & 0x80)
+ { for (i=6;i>=0;i--)
+ { brw += (int)v1[i]-(int)v2[i];
+ sat |= ~brw;
+ brw >>= 8;
+ }
+ }
+ else
+ { for (i=6;i>=0;i--)
+ { brw += (int)v1[i]-(int)v2[i];
+ sat |= brw;
+ brw >>= 8;
+ }
+ }
+ brw <<= 8; /* brw is either 0 or -256 */
+
+ if (sat&0xff) return brw | 0x80;
+ else return brw + (ret&0xFF);
+}
+
+static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
+ int len, int peek);
+static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap);
+static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap);
+static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
+ unsigned int *is_next_epoch);
+#if 0
+static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr,
+ unsigned short *priority, unsigned long *offset);
+#endif
+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
+dtls1_copy_record(SSL *s, pitem *item)
+ {
+ DTLS1_RECORD_DATA *rdata;
+
+ rdata = (DTLS1_RECORD_DATA *)item->data;
+
+ if (s->s3->rbuf.buf != NULL)
+ OPENSSL_free(s->s3->rbuf.buf);
+
+ s->packet = rdata->packet;
+ 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);
+ }
+
+
+static 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(DTLS1_RECORD_DATA));
+ item = pitem_new(priority, rdata);
+ if (rdata == NULL || item == NULL)
+ {
+ if (rdata != NULL) OPENSSL_free(rdata);
+ if (item != NULL) pitem_free(item);
+
+ SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
+ return(0);
+ }
+
+ rdata->packet = s->packet;
+ rdata->packet_length = s->packet_length;
+ memcpy(&(rdata->rbuf), &(s->s3->rbuf), sizeof(SSL3_BUFFER));
+ memcpy(&(rdata->rrec), &(s->s3->rrec), sizeof(SSL3_RECORD));
+
+ item->data = rdata;
+
+ /* insert should not fail, since duplicates are dropped */
+ if (pqueue_insert(queue->q, item) == NULL)
+ {
+ OPENSSL_free(rdata);
+ pitem_free(item);
+ return(0);
+ }
+
+ s->packet = NULL;
+ s->packet_length = 0;
+ memset(&(s->s3->rbuf), 0, sizeof(SSL3_BUFFER));
+ memset(&(s->s3->rrec), 0, sizeof(SSL3_RECORD));
+
+ if (!ssl3_setup_buffers(s))
+ {
+ SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
+ OPENSSL_free(rdata);
+ pitem_free(item);
+ return(0);
+ }
+
+ return(1);
+ }
+
+
+static 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)->d1->unprocessed_rcds))
+
+/* retrieve a buffered record that belongs to the current epoch, ie, processed */
+#define dtls1_get_processed_record(s) \
+ dtls1_retrieve_buffered_record((s), \
+ &((s)->d1->processed_rcds))
+
+static int
+dtls1_process_buffered_records(SSL *s)
+ {
+ pitem *item;
+
+ item = pqueue_peek(s->d1->unprocessed_rcds.q);
+ if (item)
+ {
+ /* Check if epoch is current. */
+ if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch)
+ return(1); /* Nothing to do. */
+
+ /* Process all the records. */
+ while (pqueue_peek(s->d1->unprocessed_rcds.q))
+ {
+ dtls1_get_unprocessed_record(s);
+ if ( ! dtls1_process_record(s))
+ return(0);
+ dtls1_buffer_record(s, &(s->d1->processed_rcds),
+ s->s3->rrec.seq_num);
+ }
+ }
+
+ /* sync epoch numbers once all the unprocessed records
+ * have been processed */
+ s->d1->processed_rcds.epoch = s->d1->r_epoch;
+ s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1;
+
+ return(1);
+ }
+
+
+#if 0
+
+static int
+dtls1_get_buffered_record(SSL *s)
+ {
+ pitem *item;
+ PQ_64BIT priority =
+ (((PQ_64BIT)s->d1->handshake_read_seq) << 32) |
+ ((PQ_64BIT)s->d1->r_msg_hdr.frag_off);
+
+ if ( ! SSL_in_init(s)) /* if we're not (re)negotiating,
+ nothing buffered */
+ return 0;
+
+
+ item = pqueue_peek(s->d1->rcvd_records);
+ if (item && item->priority == priority)
+ {
+ /* Check if we've received the record of interest. It must be
+ * a handshake record, since data records as passed up without
+ * buffering */
+ DTLS1_RECORD_DATA *rdata;
+ item = pqueue_pop(s->d1->rcvd_records);
+ rdata = (DTLS1_RECORD_DATA *)item->data;
+
+ if (s->s3->rbuf.buf != NULL)
+ OPENSSL_free(s->s3->rbuf.buf);
+
+ s->packet = rdata->packet;
+ s->packet_length = rdata->packet_length;
+ memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
+ memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
+
+ OPENSSL_free(item->data);
+ pitem_free(item);
+
+ /* s->d1->next_expected_seq_num++; */
+ return(1);
+ }
+
+ return 0;
+ }
+
+#endif
+
+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;
+
+ /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
+ * and we have that many bytes in s->packet
+ */
+ rr->input= &(s->packet[DTLS1_RT_HEADER_LENGTH]);
+
+ /* ok, we can now read from 's->packet' data into 'rr'
+ * rr->input points at rr->length bytes, which
+ * need to be copied into rr->data by either
+ * the decryption or by the decompression
+ * When the data is 'copied' into the rr->data buffer,
+ * rr->input will be pointed at the new buffer */
+
+ /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
+ * rr->length bytes of encrypted compressed stuff. */
+
+ /* check is not needed I believe */
+ if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
+ {
+ al=SSL_AD_RECORD_OVERFLOW;
+ SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
+ goto f_err;
+ }
+
+ /* decrypt in place in 'rr->input' */
+ rr->data=rr->input;
+
+ enc_err = s->method->ssl3_enc->enc(s,0);
+ if (enc_err <= 0)
+ {
+ if (enc_err == 0)
+ /* SSLerr() and ssl3_send_alert() have been called */
+ goto err;
+
+ /* otherwise enc_err == -1 */
+ al=SSL_AD_BAD_RECORD_MAC;
+ goto f_err;
+ }
+
+#ifdef TLS_DEBUG
+printf("dec %d\n",rr->length);
+{ unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
+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)
+ {
+ /* !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 err;
+#endif
+ }
+ /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
+ if (rr->length < mac_size)
+ {
+#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 err;
+#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)
+ {
+ goto err;
+ }
+ }
+
+ /* r->length is now just compressed */
+ if (s->expand != NULL)
+ {
+ if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH)
+ {
+ al=SSL_AD_RECORD_OVERFLOW;
+ SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
+ goto f_err;
+ }
+ if (!ssl3_do_uncompress(s))
+ {
+ al=SSL_AD_DECOMPRESSION_FAILURE;
+ SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_BAD_DECOMPRESSION);
+ goto f_err;
+ }
+ }
+
+ if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH)
+ {
+ al=SSL_AD_RECORD_OVERFLOW;
+ SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
+ goto f_err;
+ }
+
+ rr->off=0;
+ /* So at this point the following is true
+ * ssl->s3->rrec.type is the type of record
+ * ssl->s3->rrec.length == number of bytes in record
+ * ssl->s3->rrec.off == offset to first valid byte
+ * ssl->s3->rrec.data == where to take bytes from, increment
+ * after use :-).
+ */
+
+ /* we have pulled in a full packet so zero things */
+ s->packet_length=0;
+ dtls1_record_bitmap_update(s, &(s->d1->bitmap));/* Mark receipt of record. */
+ return(1);
+
+f_err:
+ ssl3_send_alert(s,SSL3_AL_FATAL,al);
+err:
+ return(0);
+}
+
+
+/* Call this to get a new input record.
+ * It will return <= 0 if more data is needed, normally due to an error
+ * or non-blocking IO.
+ * When it finishes, one packet has been decoded and can be found in
+ * ssl->s3->rrec.type - is the type of record
+ * ssl->s3->rrec.data, - data
+ * ssl->s3->rrec.length, - number of bytes
+ */
+/* used only by dtls1_read_bytes */
+int dtls1_get_record(SSL *s)
+ {
+ int ssl_major,ssl_minor;
+ int i,n;
+ SSL3_RECORD *rr;
+ unsigned char *p = NULL;
+ unsigned short version;
+ DTLS1_BITMAP *bitmap;
+ unsigned int is_next_epoch;
+
+ rr= &(s->s3->rrec);
+
+ /* The epoch may have changed. If so, process all the
+ * pending records. This is a non-blocking operation. */
+ dtls1_process_buffered_records(s);
+
+ /* if we're renegotiating, then there may be buffered records */
+ if (dtls1_get_processed_record(s))
+ return 1;
+
+ /* get something from the wire */
+again:
+ /* check if we have the header */
+ if ( (s->rstate != SSL_ST_READ_BODY) ||
+ (s->packet_length < DTLS1_RT_HEADER_LENGTH))
+ {
+ n=ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
+ /* read timeout is handled by dtls1_read_bytes */
+ if (n <= 0) return(n); /* error or non-blocking */
+
+ /* 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;
+
+ /* Pull apart the header into the DTLS1_RECORD */
+ rr->type= *(p++);
+ ssl_major= *(p++);
+ ssl_minor= *(p++);
+ version=(ssl_major<<8)|ssl_minor;
+
+ /* sequence number is 64 bits, with top 2 bytes = epoch */
+ n2s(p,rr->epoch);
+
+ memcpy(&(s->s3->read_sequence[2]), p, 6);
+ p+=6;
+
+ n2s(p,rr->length);
+
+ /* Lets check version */
+ if (!s->first_packet)
+ {
+ if (version != s->version)
+ {
+ /* unexpected version, silently discard */
+ rr->length = 0;
+ s->packet_length = 0;
+ goto again;
+ }
+ }
+
+ if ((version & 0xff00) != (s->version & 0xff00))
+ {
+ /* wrong version, silently discard record */
+ rr->length = 0;
+ s->packet_length = 0;
+ goto again;
+ }
+
+ if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
+ {
+ /* record too long, silently discard it */
+ rr->length = 0;
+ s->packet_length = 0;
+ goto again;
+ }
+
+ /* now s->rstate == SSL_ST_READ_BODY */
+ }
+
+ /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
+
+ if (rr->length > s->packet_length-DTLS1_RT_HEADER_LENGTH)
+ {
+ /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
+ i=rr->length;
+ n=ssl3_read_n(s,i,i,1);
+ if (n <= 0) return(n); /* error or non-blocking io */
+
+ /* this packet contained a partial record, dump it */
+ if ( n != i)
+ {
+ rr->length = 0;
+ s->packet_length = 0;
+ goto again;
+ }
+
+ /* now n == rr->length,
+ * and s->packet_length == DTLS1_RT_HEADER_LENGTH + rr->length */
+ }
+ s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
+
+ /* match epochs. NULL means the packet is dropped on the floor */
+ 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.
+ * 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 */
+ }
+
+ /* just read a 0 length packet */
+ if (rr->length == 0) goto again;
+
+ /* If this record is from the next epoch (either HM or ALERT),
+ * and a handshake is currently in progress, buffer it since it
+ * cannot be processed at this time. */
+ if (is_next_epoch)
+ {
+ if (SSL_in_init(s) || s->in_handshake)
+ {
+ 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))
+ {
+ rr->length = 0;
+ s->packet_length = 0; /* dump this record */
+ goto again; /* get another record */
+ }
+
+ dtls1_clear_timeouts(s); /* done waiting */
+ 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), ChangeCipherSpec records (not really
+ * a surprise, but handled as if it were), or renegotiation requests.
+ * 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, 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 (s->s3->rbuf.buf == NULL) /* Not initialized yet */
+ if (!ssl3_setup_buffers(s))
+ return(-1);
+
+ /* XXX: check what the second '&& type' is about */
+ if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
+ (type != SSL3_RT_HANDSHAKE) && type) ||
+ (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, peek)))
+ return ret;
+
+ /* Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
+
+ if (!s->in_handshake && 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->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)
+ {
+ 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))
+ {
+ 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;
+ }
+ }
+
+ /* 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))
+ {
+ /* 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
+ * (even in 'peek' mode) */
+ if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
+ {
+ rr->length=0;
+ s->rwstate=SSL_NOTHING;
+ return(0);
+ }
+
+
+ if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
+ {
+ /* 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 (len <= 0) return(len);
+
+ if ((unsigned int)len > rr->length)
+ n = rr->length;
+ else
+ n = (unsigned int)len;
+
+ memcpy(buf,&(rr->data[rr->off]),n);
+ if (!peek)
+ {
+ rr->length-=n;
+ rr->off+=n;
+ if (rr->length == 0)
+ {
+ s->rstate=SSL_ST_READ_HEADER;
+ rr->off=0;
+ }
+ }
+ 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 (rr->type == SSL3_RT_HANDSHAKE)
+ {
+ dest_maxlen = sizeof s->d1->handshake_fragment;
+ dest = s->d1->handshake_fragment;
+ dest_len = &s->d1->handshake_fragment_len;
+ }
+ else if (rr->type == SSL3_RT_ALERT)
+ {
+ dest_maxlen = sizeof(s->d1->alert_fragment);
+ dest = s->d1->alert_fragment;
+ dest_len = &s->d1->alert_fragment_len;
+ }
+ /* 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)
+ {
+ /* XDTLS: In a pathalogical case, the Client Hello
+ * may be fragmented--don't always expect dest_maxlen bytes */
+ if ( rr->length < 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->rstate=SSL_ST_READ_HEADER;
+ rr->length = 0;
+ goto start;
+ }
+
+ /* now move 'n' bytes: */
+ for ( k = 0; k < dest_maxlen; k++)
+ {
+ dest[k] = rr->data[rr->off++];
+ rr->length--;
+ }
+ *dest_len = dest_maxlen;
+ }
+ }
+
+ /* s->d1->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE;
+ * s->d1->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->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
+ (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
+ (s->session != NULL) && (s->session->cipher != NULL))
+ {
+ s->d1->handshake_fragment_len = 0;
+
+ if ((s->d1->handshake_fragment[1] != 0) ||
+ (s->d1->handshake_fragment[2] != 0) ||
+ (s->d1->handshake_fragment[3] != 0))
+ {
+ al=SSL_AD_DECODE_ERROR;
+ SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
+ goto 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->d1->handshake_fragment, 4, s, s->msg_callback_arg);
+
+ if (SSL_is_init_finished(s) &&
+ !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
+ !s->s3->renegotiate)
+ {
+ 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 (s->s3->rbuf.left == 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);
+ }
+ }
+ }
+ }
+ /* we either finished a handshake or ignored the request,
+ * now try again to obtain the (application) data we were asked for */
+ goto start;
+ }
+
+ if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH)
+ {
+ int alert_level = s->d1->alert_fragment[0];
+ int alert_descr = s->d1->alert_fragment[1];
+
+ s->d1->alert_fragment_len = 0;
+
+ if (s->msg_callback)
+ s->msg_callback(0, s->version, SSL3_RT_ALERT,
+ s->d1->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 == 1) /* warning */
+ {
+ s->s3->warn_alert = alert_descr;
+ if (alert_descr == SSL_AD_CLOSE_NOTIFY)
+ {
+ 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->d1->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 == 2) /* 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->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;
+ rr->length=0;
+ return(0);
+ }
+
+ 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 != ccs_hdr_len) ||
+ (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS))
+ {
+ i=SSL_AD_ILLEGAL_PARAMETER;
+ SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
+ goto err;
+ }
+
+ rr->length=0;
+
+ if (s->msg_callback)
+ 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;
+
+ /* 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++;
+
+ goto start;
+ }
+
+ /* Unexpected handshake message (Client Hello, or protocol violation) */
+ if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
+ !s->in_handshake)
+ {
+ struct hm_header_st msg_hdr;
+
+ /* this may just be a stale retransmit */
+ dtls1_get_message_header(rr->data, &msg_hdr);
+ if( rr->epoch != s->d1->r_epoch)
+ {
+ rr->length = 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)
+ {
+ 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))
+ {
+#if 0 /* worked only because C operator preferences are not as expected (and
+ * because this is not really needed for clients except for detecting
+ * protocol violations): */
+ s->state=SSL_ST_BEFORE|(s->server)
+ ?SSL_ST_ACCEPT
+ :SSL_ST_CONNECT;
+#else
+ s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
+#endif
+ 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 (s->s3->rbuf.left == 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 (rr->type)
+ {
+ default:
+#ifndef OPENSSL_NO_TLS
+ /* TLS just ignores unknown message types */
+ if (s->version == TLS1_VERSION)
+ {
+ rr->length = 0;
+ goto start;
+ }
+#endif
+ 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 s->in_handshake is set, 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) &&
+ ((
+ (s->state & SSL_ST_CONNECT) &&
+ (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
+ (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
+ ) || (
+ (s->state & SSL_ST_ACCEPT) &&
+ (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
+ (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
+ )
+ ))
+ {
+ 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);
+err:
+ return(-1);
+ }
+
+int
+dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
+ {
+ int i;
+
+ if (SSL_in_init(s) && !s->in_handshake)
+ {
+ i=s->handshake_func(s);
+ if (i < 0) return(i);
+ if (i == 0)
+ {
+ SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
+ return -1;
+ }
+ }
+
+ if (len > SSL3_RT_MAX_PLAIN_LENGTH)
+ {
+ SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_DTLS_MESSAGE_TOO_BIG);
+ return -1;
+ }
+
+ i = dtls1_write_bytes(s, type, buf_, len);
+ return i;
+ }
+
+
+ /* 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, int peek)
+ {
+
+ if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
+ /* (partially) satisfy request from storage */
+ {
+ unsigned char *src = s->d1->handshake_fragment;
+ unsigned char *dst = buf;
+ unsigned int k,n;
+
+ /* peek == 0 */
+ n = 0;
+ while ((len > 0) && (s->d1->handshake_fragment_len > 0))
+ {
+ *dst++ = *src++;
+ len--; s->d1->handshake_fragment_len--;
+ n++;
+ }
+ /* move any remaining fragment bytes: */
+ for (k = 0; k < s->d1->handshake_fragment_len; k++)
+ s->d1->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;
+ 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 */
+ if (s->s3->wbuf.left != 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;
+
+ wr= &(s->s3->wrec);
+ wb= &(s->s3->wbuf);
+ 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;
+ }
+
+ /* DTLS implements explicit IV, so no need for empty fragments */
+#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_BAD_VER)
+ {
+ /* countermeasure against known-IV weakness in CBC ciphersuites
+ * (see http://www.openssl.org/~bodo/tls-cbc.txt)
+ */
+
+ if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
+ {
+ /* recursive function call with 'create_empty_fragment' set;
+ * this prepares and buffers the data for an empty fragment
+ * (these 'prefix_len' bytes are sent out later
+ * together with the actual payload) */
+ prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1);
+ if (prefix_len <= 0)
+ goto err;
+
+ if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
+ {
+ /* insufficient space */
+ SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+ }
+
+ 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;
+
+ /* 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;
+
+ wr->data=p + bs; /* make room for IV in case of CBC */
+ wr->length=(int)len;
+ wr->input=(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))
+ {
+ SSLerr(SSL_F_DO_DTLS1_WRITE,SSL_R_COMPRESSION_FAILURE);
+ goto err;
+ }
+ }
+ else
+ {
+ memcpy(wr->data,wr->input,wr->length);
+ wr->input=wr->data;
+ }
+
+ /* 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,&(p[wr->length + bs]),1) < 0)
+ goto err;
+ wr->length+=mac_size;
+ }
+
+ /* this is true regardless of mac size */
+ 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;
+ }
+
+ s->method->ssl3_enc->enc(s,1);
+
+ /* 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->d1->w_epoch, pseq);
+
+ /* XDTLS: ?? */
+/* else
+ s2n(s->d1->handshake_epoch, pseq); */
+
+ memcpy(pseq, &(s->s3->write_sequence[2]), 6);
+ pseq+=6;
+ s2n(wr->length,pseq);
+
+ /* we should now have
+ * wr->data pointing to the encrypted data, which is
+ * wr->length long */
+ wr->type=type; /* not needed but helps for debugging */
+ wr->length+=DTLS1_RT_HEADER_LENGTH;
+
+#if 0 /* this is now done at the message layer */
+ /* buffer the record, making it easy to handle retransmits */
+ if ( type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
+ dtls1_buffer_record(s, wr->data, wr->length,
+ *((PQ_64BIT *)&(s->s3->write_sequence[0])));
+#endif
+
+ ssl3_record_sequence_update(&(s->s3->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 */
+ wb->left = prefix_len + wr->length;
+ wb->offset = 0;
+
+ /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
+ s->s3->wpend_tot=len;
+ s->s3->wpend_buf=buf;
+ s->s3->wpend_type=type;
+ s->s3->wpend_ret=len;
+
+ /* we now just need to write the buffer */
+ return ssl3_write_pending(s,type,buf,len);
+err:
+ return -1;
+ }
+
+
+
+static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
+ {
+ int cmp;
+ unsigned int shift;
+ const unsigned char *seq = s->s3->read_sequence;
+
+ cmp = satsub64be(seq,bitmap->max_seq_num);
+ if (cmp > 0)
+ {
+ memcpy (s->s3->rrec.seq_num,seq,8);
+ return 1; /* this record in new */
+ }
+ shift = -cmp;
+ if (shift >= sizeof(bitmap->map)*8)
+ return 0; /* stale, outside the window */
+ else if (bitmap->map & (1UL<<shift))
+ return 0; /* record previously received */
+
+ memcpy (s->s3->rrec.seq_num,seq,8);
+ return 1;
+ }
+
+
+static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
+ {
+ int cmp;
+ unsigned int shift;
+ const unsigned char *seq = s->s3->read_sequence;
+
+ cmp = satsub64be(seq,bitmap->max_seq_num);
+ if (cmp > 0)
+ {
+ shift = cmp;
+ if (shift < sizeof(bitmap->map)*8)
+ bitmap->map <<= shift, bitmap->map |= 1UL;
+ else
+ bitmap->map = 1UL;
+ memcpy(bitmap->max_seq_num,seq,8);
+ }
+ else {
+ shift = -cmp;
+ if (shift < sizeof(bitmap->map)*8)
+ bitmap->map |= 1UL<<shift;
+ }
+ }
+
+
+int dtls1_dispatch_alert(SSL *s)
+ {
+ int i,j;
+ void (*cb)(const SSL *ssl,int type,int val)=NULL;
+ unsigned char buf[DTLS1_AL_HEADER_LENGTH];
+ unsigned char *ptr = &buf[0];
+
+ s->s3->alert_dispatch=0;
+
+ memset(buf, 0x00, sizeof(buf));
+ *ptr++ = s->s3->send_alert[0];
+ *ptr++ = s->s3->send_alert[1];
+
+#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
+ if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
+ {
+ s2n(s->d1->handshake_read_seq, ptr);
+#if 0
+ if ( s->d1->r_msg_hdr.frag_off == 0) /* waiting for a new msg */
+
+ else
+ s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */
+#endif
+
+#if 0
+ fprintf(stderr, "s->d1->handshake_read_seq = %d, s->d1->r_msg_hdr.seq = %d\n",s->d1->handshake_read_seq,s->d1->r_msg_hdr.seq);
+#endif
+ l2n3(s->d1->r_msg_hdr.frag_off, ptr);
+ }
+#endif
+
+ i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0);
+ if (i <= 0)
+ {
+ s->s3->alert_dispatch=1;
+ /* fprintf( stderr, "not done with alert\n" ); */
+ }
+ else
+ {
+ if (s->s3->send_alert[0] == SSL3_AL_FATAL
+#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
+ || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
+#endif
+ )
+ (void)BIO_flush(s->wbio);
+
+ if (s->msg_callback)
+ s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
+ 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=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
+ cb(s,SSL_CB_WRITE_ALERT,j);
+ }
+ }
+ return(i);
+ }
+
+
+static 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->d1->r_epoch)
+ return &s->d1->bitmap;
+
+ /* Only HM and ALERT messages can be from the next epoch */
+ else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
+ (rr->type == SSL3_RT_HANDSHAKE ||
+ rr->type == SSL3_RT_ALERT))
+ {
+ *is_next_epoch = 1;
+ return &s->d1->next_bitmap;
+ }
+
+ return NULL;
+ }
+
+#if 0
+static int
+dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, unsigned short *priority,
+ unsigned long *offset)
+ {
+
+ /* alerts are passed up immediately */
+ if ( rr->type == SSL3_RT_APPLICATION_DATA ||
+ rr->type == SSL3_RT_ALERT)
+ return 0;
+
+ /* Only need to buffer if a handshake is underway.
+ * (this implies that Hello Request and Client Hello are passed up
+ * immediately) */
+ if ( SSL_in_init(s))
+ {
+ unsigned char *data = rr->data;
+ /* need to extract the HM/CCS sequence number here */
+ if ( rr->type == SSL3_RT_HANDSHAKE ||
+ rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
+ {
+ unsigned short seq_num;
+ struct hm_header_st msg_hdr;
+ struct ccs_header_st ccs_hdr;
+
+ if ( rr->type == SSL3_RT_HANDSHAKE)
+ {
+ dtls1_get_message_header(data, &msg_hdr);
+ seq_num = msg_hdr.seq;
+ *offset = msg_hdr.frag_off;
+ }
+ else
+ {
+ dtls1_get_ccs_header(data, &ccs_hdr);
+ seq_num = ccs_hdr.seq;
+ *offset = 0;
+ }
+
+ /* this is either a record we're waiting for, or a
+ * retransmit of something we happened to previously
+ * receive (higher layers will drop the repeat silently */
+ if ( seq_num < s->d1->handshake_read_seq)
+ return 0;
+ if (rr->type == SSL3_RT_HANDSHAKE &&
+ seq_num == s->d1->handshake_read_seq &&
+ msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
+ return 0;
+ else if ( seq_num == s->d1->handshake_read_seq &&
+ (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
+ msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
+ return 0;
+ else
+ {
+ *priority = seq_num;
+ return 1;
+ }
+ }
+ else /* unknown record type */
+ return 0;
+ }
+
+ return 0;
+ }
+#endif
+
+void
+dtls1_reset_seq_numbers(SSL *s, int rw)
+ {
+ unsigned char *seq;
+ unsigned int seq_bytes = sizeof(s->s3->read_sequence);
+
+ if ( rw & SSL3_CC_READ)
+ {
+ seq = s->s3->read_sequence;
+ s->d1->r_epoch++;
+ memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP));
+ memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
+ }
+ 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));
+ }
|