diff options
Diffstat (limited to 'openssl/ssl/d1_both.c')
| -rw-r--r-- | openssl/ssl/d1_both.c | 1193 |
1 files changed, 1193 insertions, 0 deletions
diff --git a/openssl/ssl/d1_both.c b/openssl/ssl/d1_both.c new file mode 100644 index 000000000..15a201a25 --- /dev/null +++ b/openssl/ssl/d1_both.c @@ -0,0 +1,1193 @@ +/* ssl/d1_both.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 <limits.h> +#include <string.h> +#include <stdio.h> +#include "ssl_locl.h" +#include <openssl/buffer.h> +#include <openssl/rand.h> +#include <openssl/objects.h> +#include <openssl/evp.h> +#include <openssl/x509.h> + + +/* XDTLS: figure out the right values */ +static unsigned int g_probable_mtu[] = {1500 - 28, 512 - 28, 256 - 28}; + +static unsigned int dtls1_min_mtu(void); +static unsigned int dtls1_guess_mtu(unsigned int curr_mtu); +static void dtls1_fix_message_header(SSL *s, unsigned long frag_off, + unsigned long frag_len); +static unsigned char *dtls1_write_message_header(SSL *s, + unsigned char *p); +static void dtls1_set_message_header_int(SSL *s, unsigned char mt, + unsigned long len, unsigned short seq_num, unsigned long frag_off, + unsigned long frag_len); +static int dtls1_retransmit_buffered_messages(SSL *s); +static long dtls1_get_message_fragment(SSL *s, int st1, int stn, + long max, int *ok); + +static hm_fragment * +dtls1_hm_fragment_new(unsigned long frag_len) + { + hm_fragment *frag = NULL; + unsigned char *buf = NULL; + + frag = (hm_fragment *)OPENSSL_malloc(sizeof(hm_fragment)); + if ( frag == NULL) + return NULL; + + if (frag_len) + { + buf = (unsigned char *)OPENSSL_malloc(frag_len); + if ( buf == NULL) + { + OPENSSL_free(frag); + return NULL; + } + } + + /* zero length fragment gets zero frag->fragment */ + frag->fragment = buf; + + return frag; + } + +static void +dtls1_hm_fragment_free(hm_fragment *frag) + { + if (frag->fragment) OPENSSL_free(frag->fragment); + OPENSSL_free(frag); + } + +/* send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or SSL3_RT_CHANGE_CIPHER_SPEC) */ +int dtls1_do_write(SSL *s, int type) + { + int ret; + int curr_mtu; + unsigned int len, frag_off; + + /* AHA! Figure out the MTU, and stick to the right size */ + if ( ! (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)) + { + s->d1->mtu = + BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL); + + /* I've seen the kernel return bogus numbers when it doesn't know + * (initial write), so just make sure we have a reasonable number */ + if ( s->d1->mtu < dtls1_min_mtu()) + { + s->d1->mtu = 0; + s->d1->mtu = dtls1_guess_mtu(s->d1->mtu); + BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SET_MTU, + s->d1->mtu, NULL); + } + } +#if 0 + mtu = s->d1->mtu; + + fprintf(stderr, "using MTU = %d\n", mtu); + + mtu -= (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH); + + curr_mtu = mtu - BIO_wpending(SSL_get_wbio(s)); + + if ( curr_mtu > 0) + mtu = curr_mtu; + else if ( ( ret = BIO_flush(SSL_get_wbio(s))) <= 0) + return ret; + + if ( BIO_wpending(SSL_get_wbio(s)) + s->init_num >= mtu) + { + ret = BIO_flush(SSL_get_wbio(s)); + if ( ret <= 0) + return ret; + mtu = s->d1->mtu - (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH); + } + + OPENSSL_assert(mtu > 0); /* should have something reasonable now */ + +#endif + + if ( s->init_off == 0 && type == SSL3_RT_HANDSHAKE) + OPENSSL_assert(s->init_num == + (int)s->d1->w_msg_hdr.msg_len + DTLS1_HM_HEADER_LENGTH); + + frag_off = 0; + while( s->init_num) + { + curr_mtu = s->d1->mtu - BIO_wpending(SSL_get_wbio(s)) - + DTLS1_RT_HEADER_LENGTH; + + if ( curr_mtu <= DTLS1_HM_HEADER_LENGTH) + { + /* grr.. we could get an error if MTU picked was wrong */ + ret = BIO_flush(SSL_get_wbio(s)); + if ( ret <= 0) + return ret; + curr_mtu = s->d1->mtu - DTLS1_RT_HEADER_LENGTH; + } + + if ( s->init_num > curr_mtu) + len = curr_mtu; + else + len = s->init_num; + + + /* XDTLS: this function is too long. split out the CCS part */ + if ( type == SSL3_RT_HANDSHAKE) + { + if ( s->init_off != 0) + { + OPENSSL_assert(s->init_off > DTLS1_HM_HEADER_LENGTH); + s->init_off -= DTLS1_HM_HEADER_LENGTH; + s->init_num += DTLS1_HM_HEADER_LENGTH; + + /* write atleast DTLS1_HM_HEADER_LENGTH bytes */ + if ( len <= DTLS1_HM_HEADER_LENGTH) + len += DTLS1_HM_HEADER_LENGTH; + } + + dtls1_fix_message_header(s, frag_off, + len - DTLS1_HM_HEADER_LENGTH); + + dtls1_write_message_header(s, (unsigned char *)&s->init_buf->data[s->init_off]); + + OPENSSL_assert(len >= DTLS1_HM_HEADER_LENGTH); + } + + ret=dtls1_write_bytes(s,type,&s->init_buf->data[s->init_off], + len); + if (ret < 0) + { + /* might need to update MTU here, but we don't know + * which previous packet caused the failure -- so can't + * really retransmit anything. continue as if everything + * is fine and wait for an alert to handle the + * retransmit + */ + if ( BIO_ctrl(SSL_get_wbio(s), + BIO_CTRL_DGRAM_MTU_EXCEEDED, 0, NULL)) + s->d1->mtu = BIO_ctrl(SSL_get_wbio(s), + BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL); + else + return(-1); + } + else + { + + /* bad if this assert fails, only part of the handshake + * message got sent. but why would this happen? */ + OPENSSL_assert(len == (unsigned int)ret); + + if (type == SSL3_RT_HANDSHAKE && ! s->d1->retransmitting) + { + /* should not be done for 'Hello Request's, but in that case + * we'll ignore the result anyway */ + unsigned char *p = (unsigned char *)&s->init_buf->data[s->init_off]; + const struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; + int xlen; + + if (frag_off == 0 && s->client_version != DTLS1_BAD_VER) + { + /* reconstruct message header is if it + * is being sent in single fragment */ + *p++ = msg_hdr->type; + l2n3(msg_hdr->msg_len,p); + s2n (msg_hdr->seq,p); + l2n3(0,p); + l2n3(msg_hdr->msg_len,p); + p -= DTLS1_HM_HEADER_LENGTH; + xlen = ret; + } + else + { + p += DTLS1_HM_HEADER_LENGTH; + xlen = ret - DTLS1_HM_HEADER_LENGTH; + } + + ssl3_finish_mac(s, p, xlen); + } + + if (ret == s->init_num) + { + if (s->msg_callback) + s->msg_callback(1, s->version, type, s->init_buf->data, + (size_t)(s->init_off + s->init_num), s, + s->msg_callback_arg); + + s->init_off = 0; /* done writing this message */ + s->init_num = 0; + + return(1); + } + s->init_off+=ret; + s->init_num-=ret; + frag_off += (ret -= DTLS1_HM_HEADER_LENGTH); + } + } + return(0); + } + + +/* Obtain handshake message of message type 'mt' (any if mt == -1), + * maximum acceptable body length 'max'. + * Read an entire handshake message. Handshake messages arrive in + * fragments. + */ +long dtls1_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok) + { + int i, al; + struct hm_header_st *msg_hdr; + + /* s3->tmp is used to store messages that are unexpected, caused + * by the absence of an optional handshake message */ + if (s->s3->tmp.reuse_message) + { + s->s3->tmp.reuse_message=0; + if ((mt >= 0) && (s->s3->tmp.message_type != mt)) + { + al=SSL_AD_UNEXPECTED_MESSAGE; + SSLerr(SSL_F_DTLS1_GET_MESSAGE,SSL_R_UNEXPECTED_MESSAGE); + goto f_err; + } + *ok=1; + s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH; + s->init_num = (int)s->s3->tmp.message_size; + return s->init_num; + } + + msg_hdr = &s->d1->r_msg_hdr; + do + { + if ( msg_hdr->frag_off == 0) + { + /* s->d1->r_message_header.msg_len = 0; */ + memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); + } + + i = dtls1_get_message_fragment(s, st1, stn, max, ok); + if ( i == DTLS1_HM_BAD_FRAGMENT || + i == DTLS1_HM_FRAGMENT_RETRY) /* bad fragment received */ + continue; + else if ( i <= 0 && !*ok) + return i; + + /* Note that s->init_sum is used as a counter summing + * up fragments' lengths: as soon as they sum up to + * handshake packet length, we assume we have got all + * the fragments. Overlapping fragments would cause + * premature termination, so we don't expect overlaps. + * Well, handling overlaps would require something more + * drastic. Indeed, as it is now there is no way to + * tell if out-of-order fragment from the middle was + * the last. '>=' is the best/least we can do to control + * the potential damage caused by malformed overlaps. */ + if ((unsigned int)s->init_num >= msg_hdr->msg_len) + { + unsigned char *p = (unsigned char *)s->init_buf->data; + unsigned long msg_len = msg_hdr->msg_len; + + /* reconstruct message header as if it was + * sent in single fragment */ + *(p++) = msg_hdr->type; + l2n3(msg_len,p); + s2n (msg_hdr->seq,p); + l2n3(0,p); + l2n3(msg_len,p); + if (s->client_version != DTLS1_BAD_VER) + p -= DTLS1_HM_HEADER_LENGTH, + msg_len += DTLS1_HM_HEADER_LENGTH; + + ssl3_finish_mac(s, p, msg_len); + if (s->msg_callback) + s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, + p, msg_len, + s, s->msg_callback_arg); + + memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); + + s->d1->handshake_read_seq++; + /* we just read a handshake message from the other side: + * this means that we don't need to retransmit of the + * buffered messages. + * XDTLS: may be able clear out this + * buffer a little sooner (i.e if an out-of-order + * handshake message/record is received at the record + * layer. + * XDTLS: exception is that the server needs to + * know that change cipher spec and finished messages + * have been received by the client before clearing this + * buffer. this can simply be done by waiting for the + * first data segment, but is there a better way? */ + dtls1_clear_record_buffer(s); + + s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH; + return s->init_num; + } + else + msg_hdr->frag_off = i; + } while(1) ; + +f_err: + ssl3_send_alert(s,SSL3_AL_FATAL,al); + *ok = 0; + return -1; + } + + +static int dtls1_preprocess_fragment(SSL *s,struct hm_header_st *msg_hdr,int max) + { + size_t frag_off,frag_len,msg_len; + + msg_len = msg_hdr->msg_len; + frag_off = msg_hdr->frag_off; + frag_len = msg_hdr->frag_len; + + /* sanity checking */ + if ( (frag_off+frag_len) > msg_len) + { + SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE); + return SSL_AD_ILLEGAL_PARAMETER; + } + + if ( (frag_off+frag_len) > (unsigned long)max) + { + SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE); + return SSL_AD_ILLEGAL_PARAMETER; + } + + if ( s->d1->r_msg_hdr.frag_off == 0) /* first fragment */ + { + /* msg_len is limited to 2^24, but is effectively checked + * against max above */ + if (!BUF_MEM_grow_clean(s->init_buf,(int)msg_len+DTLS1_HM_HEADER_LENGTH)) + { + SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,ERR_R_BUF_LIB); + return SSL_AD_INTERNAL_ERROR; + } + + s->s3->tmp.message_size = msg_len; + s->d1->r_msg_hdr.msg_len = msg_len; + s->s3->tmp.message_type = msg_hdr->type; + s->d1->r_msg_hdr.type = msg_hdr->type; + s->d1->r_msg_hdr.seq = msg_hdr->seq; + } + else if (msg_len != s->d1->r_msg_hdr.msg_len) + { + /* They must be playing with us! BTW, failure to enforce + * upper limit would open possibility for buffer overrun. */ + SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE); + return SSL_AD_ILLEGAL_PARAMETER; + } + + return 0; /* no error */ + } + + +static int +dtls1_retrieve_buffered_fragment(SSL *s, long max, int *ok) + { + /* (0) check whether the desired fragment is available + * if so: + * (1) copy over the fragment to s->init_buf->data[] + * (2) update s->init_num + */ + pitem *item; + hm_fragment *frag; + int al; + + *ok = 0; + item = pqueue_peek(s->d1->buffered_messages); + if ( item == NULL) + return 0; + + frag = (hm_fragment *)item->data; + + if ( s->d1->handshake_read_seq == frag->msg_header.seq) + { + pqueue_pop(s->d1->buffered_messages); + + al=dtls1_preprocess_fragment(s,&frag->msg_header,max); + + if (al==0) /* no alert */ + { + unsigned char *p = (unsigned char *)s->init_buf->data+DTLS1_HM_HEADER_LENGTH; + memcpy(&p[frag->msg_header.frag_off], + frag->fragment,frag->msg_header.frag_len); + } + + dtls1_hm_fragment_free(frag); + pitem_free(item); + + if (al==0) + { + *ok = 1; + return frag->msg_header.frag_len; + } + + ssl3_send_alert(s,SSL3_AL_FATAL,al); + s->init_num = 0; + *ok = 0; + return -1; + } + else + return 0; + } + + +static int +dtls1_process_out_of_seq_message(SSL *s, struct hm_header_st* msg_hdr, int *ok) +{ + int i=-1; + hm_fragment *frag = NULL; + pitem *item = NULL; + PQ_64BIT seq64; + unsigned long frag_len = msg_hdr->frag_len; + + if ((msg_hdr->frag_off+frag_len) > msg_hdr->msg_len) + goto err; + + if (msg_hdr->seq <= s->d1->handshake_read_seq) + { + unsigned char devnull [256]; + + while (frag_len) + { + i = s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE, + devnull, + frag_len>sizeof(devnull)?sizeof(devnull):frag_len,0); + if (i<=0) goto err; + frag_len -= i; + } + } + + frag = dtls1_hm_fragment_new(frag_len); + if ( frag == NULL) + goto err; + + memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); + + if (frag_len) + { + /* read the body of the fragment (header has already been read */ + i = s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE, + frag->fragment,frag_len,0); + if (i<=0 || (unsigned long)i!=frag_len) + goto err; + } + + pq_64bit_init(&seq64); + pq_64bit_assign_word(&seq64, msg_hdr->seq); + + item = pitem_new(seq64, frag); + pq_64bit_free(&seq64); + if ( item == NULL) + goto err; + + pqueue_insert(s->d1->buffered_messages, item); + return DTLS1_HM_FRAGMENT_RETRY; + +err: + if ( frag != NULL) dtls1_hm_fragment_free(frag); + if ( item != NULL) OPENSSL_free(item); + *ok = 0; + return i; + } + + +static long +dtls1_get_message_fragment(SSL *s, int st1, int stn, long max, int *ok) + { + unsigned char wire[DTLS1_HM_HEADER_LENGTH]; + unsigned long l, frag_off, frag_len; + int i,al; + struct hm_header_st msg_hdr; + + /* see if we have the required fragment already */ + if ((frag_len = dtls1_retrieve_buffered_fragment(s,max,ok)) || *ok) + { + if (*ok) s->init_num += frag_len; + return frag_len; + } + + /* read handshake message header */ + i=s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,wire, + DTLS1_HM_HEADER_LENGTH, 0); + if (i <= 0) /* nbio, or an error */ + { + s->rwstate=SSL_READING; + *ok = 0; + return i; + } + OPENSSL_assert(i == DTLS1_HM_HEADER_LENGTH); + + /* parse the message fragment header */ + dtls1_get_message_header(wire, &msg_hdr); + + /* + * if this is a future (or stale) message it gets buffered + * (or dropped)--no further processing at this time + */ + if ( msg_hdr.seq != s->d1->handshake_read_seq) + return dtls1_process_out_of_seq_message(s, &msg_hdr, ok); + + l = msg_hdr.msg_len; + frag_off = msg_hdr.frag_off; + frag_len = msg_hdr.frag_len; + + if (!s->server && s->d1->r_msg_hdr.frag_off == 0 && + wire[0] == SSL3_MT_HELLO_REQUEST) + { + /* The server may always send 'Hello Request' messages -- + * we are doing a handshake anyway now, so ignore them + * if their format is correct. Does not count for + * 'Finished' MAC. */ + if (wire[1] == 0 && wire[2] == 0 && wire[3] == 0) + { + if (s->msg_callback) + s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, + wire, DTLS1_HM_HEADER_LENGTH, s, + s->msg_callback_arg); + + s->init_num = 0; + return dtls1_get_message_fragment(s, st1, stn, + max, ok); + } + else /* Incorrectly formated Hello request */ + { + al=SSL_AD_UNEXPECTED_MESSAGE; + SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,SSL_R_UNEXPECTED_MESSAGE); + goto f_err; + } + } + + if ((al=dtls1_preprocess_fragment(s,&msg_hdr,max))) + goto f_err; + + /* XDTLS: ressurect this when restart is in place */ + s->state=stn; + + if ( frag_len > 0) + { + unsigned char *p=(unsigned char *)s->init_buf->data+DTLS1_HM_HEADER_LENGTH; + + i=s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE, + &p[frag_off],frag_len,0); + /* XDTLS: fix this--message fragments cannot span multiple packets */ + if (i <= 0) + { + s->rwstate=SSL_READING; + *ok = 0; + return i; + } + } + else + i = 0; + + /* XDTLS: an incorrectly formatted fragment should cause the + * handshake to fail */ + OPENSSL_assert(i == (int)frag_len); + + *ok = 1; + + /* Note that s->init_num is *not* used as current offset in + * s->init_buf->data, but as a counter summing up fragments' + * lengths: as soon as they sum up to handshake packet + * length, we assume we have got all the fragments. */ + s->init_num += frag_len; + return frag_len; + +f_err: + ssl3_send_alert(s,SSL3_AL_FATAL,al); + s->init_num = 0; + + *ok=0; + return(-1); + } + +int dtls1_send_finished(SSL *s, int a, int b, const char *sender, int slen) + { + unsigned char *p,*d; + int i; + unsigned long l; + + if (s->state == a) + { + d=(unsigned char *)s->init_buf->data; + p= &(d[DTLS1_HM_HEADER_LENGTH]); + + i=s->method->ssl3_enc->final_finish_mac(s, + &(s->s3->finish_dgst1), + &(s->s3->finish_dgst2), + sender,slen,s->s3->tmp.finish_md); + s->s3->tmp.finish_md_len = i; + memcpy(p, s->s3->tmp.finish_md, i); + p+=i; + l=i; + +#ifdef OPENSSL_SYS_WIN16 + /* MSVC 1.5 does not clear the top bytes of the word unless + * I do this. + */ + l&=0xffff; +#endif + + d = dtls1_set_message_header(s, d, SSL3_MT_FINISHED, l, 0, l); + s->init_num=(int)l+DTLS1_HM_HEADER_LENGTH; + s->init_off=0; + + /* buffer the message to handle re-xmits */ + dtls1_buffer_message(s, 0); + + s->state=b; + } + + /* SSL3_ST_SEND_xxxxxx_HELLO_B */ + return(dtls1_do_write(s,SSL3_RT_HANDSHAKE)); + } + +/* for these 2 messages, we need to + * ssl->enc_read_ctx re-init + * ssl->s3->read_sequence zero + * ssl->s3->read_mac_secret re-init + * ssl->session->read_sym_enc assign + * ssl->session->read_compression assign + * ssl->session->read_hash assign + */ +int dtls1_send_change_cipher_spec(SSL *s, int a, int b) + { + unsigned char *p; + + if (s->state == a) + { + p=(unsigned char *)s->init_buf->data; + *p++=SSL3_MT_CCS; + s->d1->handshake_write_seq = s->d1->next_handshake_write_seq; + s->init_num=DTLS1_CCS_HEADER_LENGTH; + + if (s->client_version == DTLS1_BAD_VER) + { + s->d1->next_handshake_write_seq++; + s2n(s->d1->handshake_write_seq,p); + s->init_num+=2; + } + + s->init_off=0; + + dtls1_set_message_header_int(s, SSL3_MT_CCS, 0, + s->d1->handshake_write_seq, 0, 0); + + /* buffer the message to handle re-xmits */ + dtls1_buffer_message(s, 1); + + s->state=b; + } + + /* SSL3_ST_CW_CHANGE_B */ + return(dtls1_do_write(s,SSL3_RT_CHANGE_CIPHER_SPEC)); + } + +unsigned long dtls1_output_cert_chain(SSL *s, X509 *x) + { + unsigned char *p; + int n,i; + unsigned long l= 3 + DTLS1_HM_HEADER_LENGTH; + BUF_MEM *buf; + X509_STORE_CTX xs_ctx; + X509_OBJECT obj; + + /* TLSv1 sends a chain with nothing in it, instead of an alert */ + buf=s->init_buf; + if (!BUF_MEM_grow_clean(buf,10)) + { + SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_BUF_LIB); + return(0); + } + if (x != NULL) + { + if(!X509_STORE_CTX_init(&xs_ctx,s->ctx->cert_store,NULL,NULL)) + { + SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_X509_LIB); + return(0); + } + + for (;;) + { + n=i2d_X509(x,NULL); + if (!BUF_MEM_grow_clean(buf,(int)(n+l+3))) + { + SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_BUF_LIB); + return(0); + } + p=(unsigned char *)&(buf->data[l]); + l2n3(n,p); + i2d_X509(x,&p); + l+=n+3; + if (X509_NAME_cmp(X509_get_subject_name(x), + X509_get_issuer_name(x)) == 0) break; + + i=X509_STORE_get_by_subject(&xs_ctx,X509_LU_X509, + X509_get_issuer_name(x),&obj); + if (i <= 0) break; + x=obj.data.x509; + /* Count is one too high since the X509_STORE_get uped the + * ref count */ + X509_free(x); + } + + X509_STORE_CTX_cleanup(&xs_ctx); + } + + /* Thawte special :-) */ + if (s->ctx->extra_certs != NULL) + for (i=0; i<sk_X509_num(s->ctx->extra_certs); i++) + { + x=sk_X509_value(s->ctx->extra_certs,i); + n=i2d_X509(x,NULL); + if (!BUF_MEM_grow_clean(buf,(int)(n+l+3))) + { + SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_BUF_LIB); + return(0); + } + p=(unsigned char *)&(buf->data[l]); + l2n3(n,p); + i2d_X509(x,&p); + l+=n+3; + } + + l-= (3 + DTLS1_HM_HEADER_LENGTH); + + p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]); + l2n3(l,p); + l+=3; + p=(unsigned char *)&(buf->data[0]); + p = dtls1_set_message_header(s, p, SSL3_MT_CERTIFICATE, l, 0, l); + + l+=DTLS1_HM_HEADER_LENGTH; + return(l); + } + +int dtls1_read_failed(SSL *s, int code) + { + DTLS1_STATE *state; + BIO *bio; + int send_alert = 0; + + if ( code > 0) + { + fprintf( stderr, "invalid state reached %s:%d", __FILE__, __LINE__); + return 1; + } + + bio = SSL_get_rbio(s); + if ( ! BIO_dgram_recv_timedout(bio)) + { + /* not a timeout, none of our business, + let higher layers handle this. in fact it's probably an error */ + return code; + } + + if ( ! SSL_in_init(s)) /* done, no need to send a retransmit */ + { + BIO_set_flags(SSL_get_rbio(s), BIO_FLAGS_READ); + return code; + } + + state = s->d1; + state->timeout.num_alerts++; + if ( state->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT) + { + /* fail the connection, enough alerts have been sent */ + SSLerr(SSL_F_DTLS1_READ_FAILED,SSL_R_READ_TIMEOUT_EXPIRED); + return 0; + } + + state->timeout.read_timeouts++; + if ( state->timeout.read_timeouts > DTLS1_TMO_READ_COUNT) + { + send_alert = 1; + state->timeout.read_timeouts = 1; + } + + +#if 0 /* for now, each alert contains only one record number */ + item = pqueue_peek(state->rcvd_records); + if ( item ) + { + /* send an alert immediately for all the missing records */ + } + else +#endif + +#if 0 /* no more alert sending, just retransmit the last set of messages */ + if ( send_alert) + ssl3_send_alert(s,SSL3_AL_WARNING, + DTLS1_AD_MISSING_HANDSHAKE_MESSAGE); +#endif + + return dtls1_retransmit_buffered_messages(s) ; + } + + +static int +dtls1_retransmit_buffered_messages(SSL *s) + { + pqueue sent = s->d1->sent_messages; + piterator iter; + pitem *item; + hm_fragment *frag; + int found = 0; + + iter = pqueue_iterator(sent); + + for ( item = pqueue_next(&iter); item != NULL; item = pqueue_next(&iter)) + { + frag = (hm_fragment *)item->data; + if ( dtls1_retransmit_message(s, frag->msg_header.seq, 0, &found) <= 0 && + found) + { + fprintf(stderr, "dtls1_retransmit_message() failed\n"); + return -1; + } + } + + return 1; + } + +int +dtls1_buffer_message(SSL *s, int is_ccs) + { + pitem *item; + hm_fragment *frag; + PQ_64BIT seq64; + unsigned int epoch = s->d1->w_epoch; + + /* this function is called immediately after a message has + * been serialized */ + OPENSSL_assert(s->init_off == 0); + + frag = dtls1_hm_fragment_new(s->init_num); + + memcpy(frag->fragment, s->init_buf->data, s->init_num); + + if ( is_ccs) + { + OPENSSL_assert(s->d1->w_msg_hdr.msg_len + + DTLS1_CCS_HEADER_LENGTH <= (unsigned int)s->init_num); + epoch++; + } + else + { + OPENSSL_assert(s->d1->w_msg_hdr.msg_len + + DTLS1_HM_HEADER_LENGTH == (unsigned int)s->init_num); + } + + frag->msg_header.msg_len = s->d1->w_msg_hdr.msg_len; + frag->msg_header.seq = s->d1->w_msg_hdr.seq; + frag->msg_header.type = s->d1->w_msg_hdr.type; + frag->msg_header.frag_off = 0; + frag->msg_header.frag_len = s->d1->w_msg_hdr.msg_len; + frag->msg_header.is_ccs = is_ccs; + + pq_64bit_init(&seq64); + pq_64bit_assign_word(&seq64, epoch<<16 | frag->msg_header.seq); + + item = pitem_new(seq64, frag); + pq_64bit_free(&seq64); + if ( item == NULL) + { + dtls1_hm_fragment_free(frag); + return 0; + } + +#if 0 + fprintf( stderr, "buffered messge: \ttype = %xx\n", msg_buf->type); + fprintf( stderr, "\t\t\t\t\tlen = %d\n", msg_buf->len); + fprintf( stderr, "\t\t\t\t\tseq_num = %d\n", msg_buf->seq_num); +#endif + + pqueue_insert(s->d1->sent_messages, item); + return 1; + } + +int +dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off, + int *found) + { + int ret; + /* XDTLS: for now assuming that read/writes are blocking */ + pitem *item; + hm_fragment *frag ; + unsigned long header_length; + PQ_64BIT seq64; + + /* + OPENSSL_assert(s->init_num == 0); + OPENSSL_assert(s->init_off == 0); + */ + + /* XDTLS: the requested message ought to be found, otherwise error */ + pq_64bit_init(&seq64); + pq_64bit_assign_word(&seq64, seq); + + item = pqueue_find(s->d1->sent_messages, seq64); + pq_64bit_free(&seq64); + if ( item == NULL) + { + fprintf(stderr, "retransmit: message %d non-existant\n", seq); + *found = 0; + return 0; + } + + *found = 1; + frag = (hm_fragment *)item->data; + + if ( frag->msg_header.is_ccs) + header_length = DTLS1_CCS_HEADER_LENGTH; + else + header_length = DTLS1_HM_HEADER_LENGTH; + + memcpy(s->init_buf->data, frag->fragment, + frag->msg_header.msg_len + header_length); + s->init_num = frag->msg_header.msg_len + header_length; + + dtls1_set_message_header_int(s, frag->msg_header.type, + frag->msg_header.msg_len, frag->msg_header.seq, 0, + frag->msg_header.frag_len); + + s->d1->retransmitting = 1; + ret = dtls1_do_write(s, frag->msg_header.is_ccs ? + SSL3_RT_CHANGE_CIPHER_SPEC : SSL3_RT_HANDSHAKE); + s->d1->retransmitting = 0; + + (void)BIO_flush(SSL_get_wbio(s)); + return ret; + } + +/* call this function when the buffered messages are no longer needed */ +void +dtls1_clear_record_buffer(SSL *s) + { + pitem *item; + + for(item = pqueue_pop(s->d1->sent_messages); + item != NULL; item = pqueue_pop(s->d1->sent_messages)) + { + dtls1_hm_fragment_free((hm_fragment *)item->data); + pitem_free(item); + } + } + + +unsigned char * +dtls1_set_message_header(SSL *s, unsigned char *p, unsigned char mt, + unsigned long len, unsigned long frag_off, unsigned long frag_len) + { + if ( frag_off == 0) + { + s->d1->handshake_write_seq = s->d1->next_handshake_write_seq; + s->d1->next_handshake_write_seq++; + } + + dtls1_set_message_header_int(s, mt, len, s->d1->handshake_write_seq, + frag_off, frag_len); + + return p += DTLS1_HM_HEADER_LENGTH; + } + + +/* don't actually do the writing, wait till the MTU has been retrieved */ +static void +dtls1_set_message_header_int(SSL *s, unsigned char mt, + unsigned long len, unsigned short seq_num, unsigned long frag_off, + unsigned long frag_len) + { + struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; + + msg_hdr->type = mt; + msg_hdr->msg_len = len; + msg_hdr->seq = seq_num; + msg_hdr->frag_off = frag_off; + msg_hdr->frag_len = frag_len; + } + +static void +dtls1_fix_message_header(SSL *s, unsigned long frag_off, + unsigned long frag_len) + { + struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; + + msg_hdr->frag_off = frag_off; + msg_hdr->frag_len = frag_len; + } + +static unsigned char * +dtls1_write_message_header(SSL *s, unsigned char *p) + { + struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; + + *p++ = msg_hdr->type; + l2n3(msg_hdr->msg_len, p); + + s2n(msg_hdr->seq, p); + l2n3(msg_hdr->frag_off, p); + l2n3(msg_hdr->frag_len, p); + + return p; + } + +static unsigned int +dtls1_min_mtu(void) + { + return (g_probable_mtu[(sizeof(g_probable_mtu) / + sizeof(g_probable_mtu[0])) - 1]); + } + +static unsigned int +dtls1_guess_mtu(unsigned int curr_mtu) + { + size_t i; + + if ( curr_mtu == 0 ) + return g_probable_mtu[0] ; + + for ( i = 0; i < sizeof(g_probable_mtu)/sizeof(g_probable_mtu[0]); i++) + if ( curr_mtu > g_probable_mtu[i]) + return g_probable_mtu[i]; + + return curr_mtu; + } + +void +dtls1_get_message_header(unsigned char *data, struct hm_header_st *msg_hdr) + { + memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); + msg_hdr->type = *(data++); + n2l3(data, msg_hdr->msg_len); + + n2s(data, msg_hdr->seq); + n2l3(data, msg_hdr->frag_off); + n2l3(data, msg_hdr->frag_len); + } + +void +dtls1_get_ccs_header(unsigned char *data, struct ccs_header_st *ccs_hdr) + { + memset(ccs_hdr, 0x00, sizeof(struct ccs_header_st)); + + ccs_hdr->type = *(data++); + } |