diff options
Diffstat (limited to 'ssl/d1_pkt.c')
-rw-r--r-- | ssl/d1_pkt.c | 1707 |
1 files changed, 1707 insertions, 0 deletions
diff --git a/ssl/d1_pkt.c b/ssl/d1_pkt.c new file mode 100644 index 0000000000..4b3aabcfa7 --- /dev/null +++ b/ssl/d1_pkt.c @@ -0,0 +1,1707 @@ +/* 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> + +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, + unsigned long long *seq_num); +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 long long priority); +static int dtls1_process_record(SSL *s); +static unsigned long long bytes_to_long_long(unsigned char *bytes); +static void long_long_to_bytes(unsigned long long num, unsigned char *bytes); +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)); + + return(1); + } + + +static int +dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned long long priority) +{ + DTLS1_RECORD_DATA *rdata; + pitem *item; + + 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_SSL3_GET_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)); + + ssl3_setup_buffers(s); + + 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) + { + DTLS1_RECORD_DATA *rdata; + rdata = (DTLS1_RECORD_DATA *)item->data; + + /* Check if epoch is current. */ + if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch) + return(1); /* Nothing to do. */ + + /* 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; + unsigned long long priority = + (((unsigned long long)s->d1->handshake_read_seq) << 32) | + ((unsigned long long)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_SSL3_GET_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 decryption_failed_or_bad_record_mac; + } + +#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) + { + mac_size=EVP_MD_size(s->read_hash); + + 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_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG); + goto f_err; +#else + goto decryption_failed_or_bad_record_mac; +#endif + } + /* check the MAC for rr->input (it's in mac_size bytes at the tail) */ + if (rr->length < mac_size) + { +#if 0 /* OK only for stream ciphers */ + al=SSL_AD_DECODE_ERROR; + SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT); + goto f_err; +#else + goto decryption_failed_or_bad_record_mac; +#endif + } + rr->length-=mac_size; + i=s->method->ssl3_enc->mac(s,md,0); + if (memcmp(md,&(rr->data[rr->length]),mac_size) != 0) + { + goto decryption_failed_or_bad_record_mac; + } + } + + /* 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_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG); + goto f_err; + } + if (!ssl3_do_uncompress(s)) + { + al=SSL_AD_DECOMPRESSION_FAILURE; + SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION); + goto f_err; + } + } + + if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH) + { + al=SSL_AD_RECORD_OVERFLOW; + SSLerr(SSL_F_SSL3_GET_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); + +decryption_failed_or_bad_record_mac: + /* Separate 'decryption_failed' alert was introduced with TLS 1.0, + * SSL 3.0 only has 'bad_record_mac'. But unless a decryption + * failure is directly visible from the ciphertext anyway, + * we should not reveal which kind of error occured -- this + * might become visible to an attacker (e.g. via logfile) */ + al=SSL_AD_BAD_RECORD_MAC; + SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); +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,al; + int i,n; + SSL3_RECORD *rr; + SSL_SESSION *sess; + unsigned char *p; + short version; + DTLS1_BITMAP *bitmap; + unsigned long long read_sequence; + unsigned int is_next_epoch; + + rr= &(s->s3->rrec); + sess=s->session; + + /* The epoch may have changed. If so, process all the + * pending records. This is a non-blocking operation. */ + if ( ! dtls1_process_buffered_records(s)) + return 0; + + /* 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 */ + + OPENSSL_assert(s->packet_length == DTLS1_RT_HEADER_LENGTH); + + 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); + + read_sequence = 0; + n2l6(p, read_sequence); + long_long_to_bytes(read_sequence, s->s3->read_sequence); + n2s(p,rr->length); + + /* Lets check version */ + if (s->first_packet) + { + s->first_packet=0; + } + else + { + if (version != s->version) + { + SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); + /* Send back error using their + * version number :-) */ + s->version=version; + al=SSL_AD_PROTOCOL_VERSION; + goto f_err; + } + } + + if ((version & 0xff00) != (DTLS1_VERSION & 0xff00)) + { + SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); + goto err; + } + + if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) + { + al=SSL_AD_RECORD_OVERFLOW; + SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG); + goto f_err; + } + + /* 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) + { + 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) + { + s->packet_length = 0; /* dump this record */ + goto again; /* get another record */ + } + + /* check whether this is a repeat, or aged record */ + if ( ! dtls1_record_replay_check(s, bitmap, &(rr->seq_num))) + { + 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), buffer it + * since it cannot be processed at this time. + * Records from the next epoch are marked as received even though they are + * not processed, so as to prevent any potential resource DoS attack */ + if (is_next_epoch) + { + dtls1_record_bitmap_update(s, bitmap); + dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num); + s->packet_length = 0; + goto again; + } + + if ( ! dtls1_process_record(s)) + return(0); + + dtls1_clear_timeouts(s); /* done waiting */ + return(1); + +f_err: + ssl3_send_alert(s,SSL3_AL_FATAL,al); +err: + return(0); + } + +/* Return up to 'len' payload bytes received in 'type' records. + * '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_SSL3_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_SSL3_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); + + /* 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)) + { + al=SSL_AD_UNEXPECTED_MESSAGE; + SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); + goto err; + } + + /* 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_SSL3_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 i, 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 /* else it's a CCS message */ + OPENSSL_assert(rr->type == SSL3_RT_CHANGE_CIPHER_SPEC); + + + 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) + { + s->rstate=SSL_ST_READ_HEADER; + rr->length = 0; + goto start; + } + + /* now move 'n' bytes: */ + for ( i = 0; i < dest_maxlen; i++) + { + dest[i] = 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_SSL3_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_SSL3_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, seq, 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_SSL3_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_SSL3_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; + + dtls1_get_ccs_header(rr->data, &ccs_hdr); + + if ( ccs_hdr.seq == s->d1->handshake_read_seq) + { + /* 'Change Cipher Spec' is just a single byte, so we know + * exactly what the record payload has to look like */ + /* XDTLS: check that epoch is consistent */ + if ( (rr->length != DTLS1_CCS_HEADER_LENGTH) || + (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS)) + { + i=SSL_AD_ILLEGAL_PARAMETER; + SSLerr(SSL_F_SSL3_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); + + 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); + + /* handshake read seq is reset upon handshake completion */ + s->d1->handshake_read_seq++; + + goto start; + } + else + { + rr->length = 0; + 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 (((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_SSL3_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; |