diff options
Diffstat (limited to 'drivers/builtin_openssl/ssl/d1_both.c')
-rw-r--r-- | drivers/builtin_openssl/ssl/d1_both.c | 1608 |
1 files changed, 1608 insertions, 0 deletions
diff --git a/drivers/builtin_openssl/ssl/d1_both.c b/drivers/builtin_openssl/ssl/d1_both.c new file mode 100644 index 0000000000..2e8cf681ed --- /dev/null +++ b/drivers/builtin_openssl/ssl/d1_both.c @@ -0,0 +1,1608 @@ +/* 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> + +#define RSMBLY_BITMASK_SIZE(msg_len) (((msg_len) + 7) / 8) + +#define RSMBLY_BITMASK_MARK(bitmask, start, end) { \ + if ((end) - (start) <= 8) { \ + long ii; \ + for (ii = (start); ii < (end); ii++) bitmask[((ii) >> 3)] |= (1 << ((ii) & 7)); \ + } else { \ + long ii; \ + bitmask[((start) >> 3)] |= bitmask_start_values[((start) & 7)]; \ + for (ii = (((start) >> 3) + 1); ii < ((((end) - 1)) >> 3); ii++) bitmask[ii] = 0xff; \ + bitmask[(((end) - 1) >> 3)] |= bitmask_end_values[((end) & 7)]; \ + } } + +#define RSMBLY_BITMASK_IS_COMPLETE(bitmask, msg_len, is_complete) { \ + long ii; \ + OPENSSL_assert((msg_len) > 0); \ + is_complete = 1; \ + if (bitmask[(((msg_len) - 1) >> 3)] != bitmask_end_values[((msg_len) & 7)]) is_complete = 0; \ + if (is_complete) for (ii = (((msg_len) - 1) >> 3) - 1; ii >= 0 ; ii--) \ + if (bitmask[ii] != 0xff) { is_complete = 0; break; } } + +#if 0 +#define RSMBLY_BITMASK_PRINT(bitmask, msg_len) { \ + long ii; \ + printf("bitmask: "); for (ii = 0; ii < (msg_len); ii++) \ + printf("%d ", (bitmask[ii >> 3] & (1 << (ii & 7))) >> (ii & 7)); \ + printf("\n"); } +#endif + +static unsigned char bitmask_start_values[] = {0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80}; +static unsigned char bitmask_end_values[] = {0xff, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f}; + +/* XDTLS: figure out the right values */ +static unsigned int g_probable_mtu[] = {1500 - 28, 512 - 28, 256 - 28}; + +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 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, int reassembly) + { + hm_fragment *frag = NULL; + unsigned char *buf = NULL; + unsigned char *bitmask = 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; + + /* Initialize reassembly bitmask if necessary */ + if (reassembly) + { + bitmask = (unsigned char *)OPENSSL_malloc(RSMBLY_BITMASK_SIZE(frag_len)); + if (bitmask == NULL) + { + if (buf != NULL) OPENSSL_free(buf); + OPENSSL_free(frag); + return NULL; + } + memset(bitmask, 0, RSMBLY_BITMASK_SIZE(frag_len)); + } + + frag->reassembly = bitmask; + + return frag; + } + +static void +dtls1_hm_fragment_free(hm_fragment *frag) + { + + if (frag->msg_header.is_ccs) + { + EVP_CIPHER_CTX_free(frag->msg_header.saved_retransmit_state.enc_write_ctx); + EVP_MD_CTX_destroy(frag->msg_header.saved_retransmit_state.write_hash); + } + if (frag->fragment) OPENSSL_free(frag->fragment); + if (frag->reassembly) OPENSSL_free(frag->reassembly); + 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, mac_size, blocksize; + + /* AHA! Figure out the MTU, and stick to the right size */ + if (s->d1->mtu < dtls1_min_mtu() && !(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); + } +#endif + + OPENSSL_assert(s->d1->mtu >= dtls1_min_mtu()); /* should have something reasonable now */ + + 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); + + if (s->write_hash) + mac_size = EVP_MD_CTX_size(s->write_hash); + else + mac_size = 0; + + if (s->enc_write_ctx && + (EVP_CIPHER_mode( s->enc_write_ctx->cipher) & EVP_CIPH_CBC_MODE)) + blocksize = 2 * EVP_CIPHER_block_size(s->enc_write_ctx->cipher); + else + blocksize = 0; + + frag_off = 0; + while( s->init_num) + { + curr_mtu = s->d1->mtu - BIO_wpending(SSL_get_wbio(s)) - + DTLS1_RT_HEADER_LENGTH - mac_size - blocksize; + + 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 - + mac_size - blocksize; + } + + 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; + + if ( s->init_num > curr_mtu) + len = curr_mtu; + else + len = s->init_num; + } + + 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) > 0 ) + 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->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; + unsigned char *p; + unsigned long msg_len; + + /* 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; + memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); + +again: + i = dtls1_get_message_fragment(s, st1, stn, max, ok); + if ( i == DTLS1_HM_BAD_FRAGMENT || + i == DTLS1_HM_FRAGMENT_RETRY) /* bad fragment received */ + goto again; + else if ( i <= 0 && !*ok) + return i; + + p = (unsigned char *)s->init_buf->data; + msg_len = msg_hdr->msg_len; + + /* reconstruct message header */ + *(p++) = msg_hdr->type; + l2n3(msg_len,p); + s2n (msg_hdr->seq,p); + l2n3(0,p); + l2n3(msg_len,p); + if (s->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)); + + /* Don't change sequence numbers while listening */ + if (!s->d1->listen) + s->d1->handshake_read_seq++; + + s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH; + return s->init_num; + +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,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; + + /* Don't return if reassembly still in progress */ + if (frag->reassembly != NULL) + return 0; + + if ( s->d1->handshake_read_seq == frag->msg_header.seq) + { + unsigned long frag_len = frag->msg_header.frag_len; + 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_len; + } + + ssl3_send_alert(s,SSL3_AL_FATAL,al); + s->init_num = 0; + *ok = 0; + return -1; + } + else + return 0; + } + + +static int +dtls1_reassemble_fragment(SSL *s, struct hm_header_st* msg_hdr, int *ok) + { + hm_fragment *frag = NULL; + pitem *item = NULL; + int i = -1, is_complete; + unsigned char seq64be[8]; + unsigned long frag_len = msg_hdr->frag_len, max_len; + + if ((msg_hdr->frag_off+frag_len) > msg_hdr->msg_len) + goto err; + + /* Determine maximum allowed message size. Depends on (user set) + * maximum certificate length, but 16k is minimum. + */ + if (DTLS1_HM_HEADER_LENGTH + SSL3_RT_MAX_ENCRYPTED_LENGTH < s->max_cert_list) + max_len = s->max_cert_list; + else + max_len = DTLS1_HM_HEADER_LENGTH + SSL3_RT_MAX_ENCRYPTED_LENGTH; + + if ((msg_hdr->frag_off+frag_len) > max_len) + goto err; + + /* Try to find item in queue */ + memset(seq64be,0,sizeof(seq64be)); + seq64be[6] = (unsigned char) (msg_hdr->seq>>8); + seq64be[7] = (unsigned char) msg_hdr->seq; + item = pqueue_find(s->d1->buffered_messages, seq64be); + + if (item == NULL) + { + frag = dtls1_hm_fragment_new(msg_hdr->msg_len, 1); + if ( frag == NULL) + goto err; + memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); + frag->msg_header.frag_len = frag->msg_header.msg_len; + frag->msg_header.frag_off = 0; + } + else + frag = (hm_fragment*) item->data; + + /* If message is already reassembled, this must be a + * retransmit and can be dropped. + */ + if (frag->reassembly == NULL) + { + 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; + } + return DTLS1_HM_FRAGMENT_RETRY; + } + + /* read the body of the fragment (header has already been read */ + i = s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE, + frag->fragment + msg_hdr->frag_off,frag_len,0); + if (i<=0 || (unsigned long)i!=frag_len) + goto err; + + RSMBLY_BITMASK_MARK(frag->reassembly, (long)msg_hdr->frag_off, + (long)(msg_hdr->frag_off + frag_len)); + + RSMBLY_BITMASK_IS_COMPLETE(frag->reassembly, (long)msg_hdr->msg_len, + is_complete); + + if (is_complete) + { + OPENSSL_free(frag->reassembly); + frag->reassembly = NULL; + } + + if (item == NULL) + { + memset(seq64be,0,sizeof(seq64be)); + seq64be[6] = (unsigned char)(msg_hdr->seq>>8); + seq64be[7] = (unsigned char)(msg_hdr->seq); + + item = pitem_new(seq64be, frag); + if (item == NULL) + { + goto err; + i = -1; + } + + 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 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; + unsigned char seq64be[8]; + unsigned long frag_len = msg_hdr->frag_len; + + if ((msg_hdr->frag_off+frag_len) > msg_hdr->msg_len) + goto err; + + /* Try to find item in queue, to prevent duplicate entries */ + memset(seq64be,0,sizeof(seq64be)); + seq64be[6] = (unsigned char) (msg_hdr->seq>>8); + seq64be[7] = (unsigned char) msg_hdr->seq; + item = pqueue_find(s->d1->buffered_messages, seq64be); + + /* If we already have an entry and this one is a fragment, + * don't discard it and rather try to reassemble it. + */ + if (item != NULL && frag_len < msg_hdr->msg_len) + item = NULL; + + /* Discard the message if sequence number was already there, is + * too far in the future, already in the queue or if we received + * a FINISHED before the SERVER_HELLO, which then must be a stale + * retransmit. + */ + if (msg_hdr->seq <= s->d1->handshake_read_seq || + msg_hdr->seq > s->d1->handshake_read_seq + 10 || item != NULL || + (s->d1->handshake_read_seq == 0 && msg_hdr->type == SSL3_MT_FINISHED)) + { + 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; + } + } + else + { + if (frag_len && frag_len < msg_hdr->msg_len) + return dtls1_reassemble_fragment(s, msg_hdr, ok); + + frag = dtls1_hm_fragment_new(frag_len, 0); + 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; + } + + memset(seq64be,0,sizeof(seq64be)); + seq64be[6] = (unsigned char)(msg_hdr->seq>>8); + seq64be[7] = (unsigned char)(msg_hdr->seq); + + item = pitem_new(seq64be, frag); + 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 len, 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; + } + /* Handshake fails if message header is incomplete */ + if (i != DTLS1_HM_HEADER_LENGTH) + { + al=SSL_AD_UNEXPECTED_MESSAGE; + SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,SSL_R_UNEXPECTED_MESSAGE); + goto f_err; + } + + /* 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 + * While listening, we accept seq 1 (ClientHello with cookie) + * although we're still expecting seq 0 (ClientHello) + */ + if (msg_hdr.seq != s->d1->handshake_read_seq && !(s->d1->listen && msg_hdr.seq == 1)) + return dtls1_process_out_of_seq_message(s, &msg_hdr, ok); + + len = msg_hdr.msg_len; + frag_off = msg_hdr.frag_off; + frag_len = msg_hdr.frag_len; + + if (frag_len && frag_len < len) + return dtls1_reassemble_fragment(s, &msg_hdr, ok); + + 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 */ + if (i != (int)frag_len) + { + al=SSL3_AD_ILLEGAL_PARAMETER; + SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,SSL3_AD_ILLEGAL_PARAMETER); + goto f_err; + } + + *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, + 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; + + /* Copy the finished so we can use it for + * renegotiation checks + */ + if(s->type == SSL_ST_CONNECT) + { + OPENSSL_assert(i <= EVP_MAX_MD_SIZE); + memcpy(s->s3->previous_client_finished, + s->s3->tmp.finish_md, i); + s->s3->previous_client_finished_len=i; + } + else + { + OPENSSL_assert(i <= EVP_MAX_MD_SIZE); + memcpy(s->s3->previous_server_finished, + s->s3->tmp.finish_md, i); + s->s3->previous_server_finished_len=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->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)); + } + +static int dtls1_add_cert_to_buf(BUF_MEM *buf, unsigned long *l, X509 *x) + { + int n; + unsigned char *p; + + n=i2d_X509(x,NULL); + if (!BUF_MEM_grow_clean(buf,(int)(n+(*l)+3))) + { + SSLerr(SSL_F_DTLS1_ADD_CERT_TO_BUF,ERR_R_BUF_LIB); + return 0; + } + p=(unsigned char *)&(buf->data[*l]); + l2n3(n,p); + i2d_X509(x,&p); + *l+=n+3; + + return 1; + } +unsigned long dtls1_output_cert_chain(SSL *s, X509 *x) + { + unsigned char *p; + int i; + unsigned long l= 3 + DTLS1_HM_HEADER_LENGTH; + BUF_MEM *buf; + + /* 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) + { + X509_STORE_CTX xs_ctx; + + if (!X509_STORE_CTX_init(&xs_ctx,s->ctx->cert_store,x,NULL)) + { + SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_X509_LIB); + return(0); + } + + X509_verify_cert(&xs_ctx); + /* Don't leave errors in the queue */ + ERR_clear_error(); + for (i=0; i < sk_X509_num(xs_ctx.chain); i++) + { + x = sk_X509_value(xs_ctx.chain, i); + + if (!dtls1_add_cert_to_buf(buf, &l, x)) + { + X509_STORE_CTX_cleanup(&xs_ctx); + return 0; + } + } + X509_STORE_CTX_cleanup(&xs_ctx); + } + /* Thawte special :-) */ + for (i=0; i<sk_X509_num(s->ctx->extra_certs); i++) + { + x=sk_X509_value(s->ctx->extra_certs,i); + if (!dtls1_add_cert_to_buf(buf, &l, x)) + return 0; + } + + 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) + { + if ( code > 0) + { + fprintf( stderr, "invalid state reached %s:%d", __FILE__, __LINE__); + return 1; + } + + if (!dtls1_is_timer_expired(s)) + { + /* not a timeout, none of our business, + let higher layers handle this. in fact it's probably an error */ + return code; + } + +#ifndef OPENSSL_NO_HEARTBEATS + if (!SSL_in_init(s) && !s->tlsext_hb_pending) /* done, no need to send a retransmit */ +#else + if (!SSL_in_init(s)) /* done, no need to send a retransmit */ +#endif + { + BIO_set_flags(SSL_get_rbio(s), BIO_FLAGS_READ); + return code; + } + +#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 ( state->timeout.read_timeouts >= DTLS1_TMO_READ_COUNT) + ssl3_send_alert(s,SSL3_AL_WARNING, + DTLS1_AD_MISSING_HANDSHAKE_MESSAGE); +#endif + + return dtls1_handle_timeout(s); + } + +int +dtls1_get_queue_priority(unsigned short seq, int is_ccs) + { + /* The index of the retransmission queue actually is the message sequence number, + * since the queue only contains messages of a single handshake. However, the + * ChangeCipherSpec has no message sequence number and so using only the sequence + * will result in the CCS and Finished having the same index. To prevent this, + * the sequence number is multiplied by 2. In case of a CCS 1 is subtracted. + * This does not only differ CSS and Finished, it also maintains the order of the + * index (important for priority queues) and fits in the unsigned short variable. + */ + return seq * 2 - is_ccs; + } + +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, + (unsigned short)dtls1_get_queue_priority(frag->msg_header.seq, frag->msg_header.is_ccs), + 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; + unsigned char seq64be[8]; + + /* 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, 0); + + memcpy(frag->fragment, s->init_buf->data, s->init_num); + + if ( is_ccs) + { + OPENSSL_assert(s->d1->w_msg_hdr.msg_len + + ((s->version==DTLS1_VERSION)?DTLS1_CCS_HEADER_LENGTH:3) == (unsigned int)s->init_num); + } + 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; + + /* save current state*/ + frag->msg_header.saved_retransmit_state.enc_write_ctx = s->enc_write_ctx; + frag->msg_header.saved_retransmit_state.write_hash = s->write_hash; + frag->msg_header.saved_retransmit_state.compress = s->compress; + frag->msg_header.saved_retransmit_state.session = s->session; + frag->msg_header.saved_retransmit_state.epoch = s->d1->w_epoch; + + memset(seq64be,0,sizeof(seq64be)); + seq64be[6] = (unsigned char)(dtls1_get_queue_priority(frag->msg_header.seq, + frag->msg_header.is_ccs)>>8); + seq64be[7] = (unsigned char)(dtls1_get_queue_priority(frag->msg_header.seq, + frag->msg_header.is_ccs)); + + item = pitem_new(seq64be, frag); + 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; + unsigned char seq64be[8]; + struct dtls1_retransmit_state saved_state; + unsigned char save_write_sequence[8]; + + /* + OPENSSL_assert(s->init_num == 0); + OPENSSL_assert(s->init_off == 0); + */ + + /* XDTLS: the requested message ought to be found, otherwise error */ + memset(seq64be,0,sizeof(seq64be)); + seq64be[6] = (unsigned char)(seq>>8); + seq64be[7] = (unsigned char)seq; + + item = pqueue_find(s->d1->sent_messages, seq64be); + 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); + + /* save current state */ + saved_state.enc_write_ctx = s->enc_write_ctx; + saved_state.write_hash = s->write_hash; + saved_state.compress = s->compress; + saved_state.session = s->session; + saved_state.epoch = s->d1->w_epoch; + saved_state.epoch = s->d1->w_epoch; + + s->d1->retransmitting = 1; + + /* restore state in which the message was originally sent */ + s->enc_write_ctx = frag->msg_header.saved_retransmit_state.enc_write_ctx; + s->write_hash = frag->msg_header.saved_retransmit_state.write_hash; + s->compress = frag->msg_header.saved_retransmit_state.compress; + s->session = frag->msg_header.saved_retransmit_state.session; + s->d1->w_epoch = frag->msg_header.saved_retransmit_state.epoch; + + if (frag->msg_header.saved_retransmit_state.epoch == saved_state.epoch - 1) + { + memcpy(save_write_sequence, s->s3->write_sequence, sizeof(s->s3->write_sequence)); + memcpy(s->s3->write_sequence, s->d1->last_write_sequence, sizeof(s->s3->write_sequence)); + } + + ret = dtls1_do_write(s, frag->msg_header.is_ccs ? + SSL3_RT_CHANGE_CIPHER_SPEC : SSL3_RT_HANDSHAKE); + + /* restore current state */ + s->enc_write_ctx = saved_state.enc_write_ctx; + s->write_hash = saved_state.write_hash; + s->compress = saved_state.compress; + s->session = saved_state.session; + s->d1->w_epoch = saved_state.epoch; + + if (frag->msg_header.saved_retransmit_state.epoch == saved_state.epoch - 1) + { + memcpy(s->d1->last_write_sequence, s->s3->write_sequence, sizeof(s->s3->write_sequence)); + memcpy(s->s3->write_sequence, save_write_sequence, sizeof(s->s3->write_sequence)); + } + + 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) + { + /* Don't change sequence numbers while listening */ + if (frag_off == 0 && !s->d1->listen) + { + 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; + } + +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) + { + unsigned int 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++); + } + +int dtls1_shutdown(SSL *s) + { + int ret; +#ifndef OPENSSL_NO_SCTP + if (BIO_dgram_is_sctp(SSL_get_wbio(s)) && + !(s->shutdown & SSL_SENT_SHUTDOWN)) + { + ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s)); + if (ret < 0) return -1; + + if (ret == 0) + BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN, 1, NULL); + } +#endif + ret = ssl3_shutdown(s); +#ifndef OPENSSL_NO_SCTP + BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN, 0, NULL); +#endif + return ret; + } + +#ifndef OPENSSL_NO_HEARTBEATS +int +dtls1_process_heartbeat(SSL *s) + { + unsigned char *p = &s->s3->rrec.data[0], *pl; + unsigned short hbtype; + unsigned int payload; + unsigned int padding = 16; /* Use minimum padding */ + + if (s->msg_callback) + s->msg_callback(0, s->version, TLS1_RT_HEARTBEAT, + &s->s3->rrec.data[0], s->s3->rrec.length, + s, s->msg_callback_arg); + + /* Read type and payload length first */ + if (1 + 2 + 16 > s->s3->rrec.length) + return 0; /* silently discard */ + hbtype = *p++; + n2s(p, payload); + if (1 + 2 + payload + 16 > s->s3->rrec.length) + return 0; /* silently discard per RFC 6520 sec. 4 */ + pl = p; + + if (hbtype == TLS1_HB_REQUEST) + { + unsigned char *buffer, *bp; + unsigned int write_length = 1 /* heartbeat type */ + + 2 /* heartbeat length */ + + payload + padding; + int r; + + if (write_length > SSL3_RT_MAX_PLAIN_LENGTH) + return 0; + + /* Allocate memory for the response, size is 1 byte + * message type, plus 2 bytes payload length, plus + * payload, plus padding + */ + buffer = OPENSSL_malloc(write_length); + bp = buffer; + + /* Enter response type, length and copy payload */ + *bp++ = TLS1_HB_RESPONSE; + s2n(payload, bp); + memcpy(bp, pl, payload); + bp += payload; + /* Random padding */ + RAND_pseudo_bytes(bp, padding); + + r = dtls1_write_bytes(s, TLS1_RT_HEARTBEAT, buffer, write_length); + + if (r >= 0 && s->msg_callback) + s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT, + buffer, write_length, + s, s->msg_callback_arg); + + OPENSSL_free(buffer); + + if (r < 0) + return r; + } + else if (hbtype == TLS1_HB_RESPONSE) + { + unsigned int seq; + + /* We only send sequence numbers (2 bytes unsigned int), + * and 16 random bytes, so we just try to read the + * sequence number */ + n2s(pl, seq); + + if (payload == 18 && seq == s->tlsext_hb_seq) + { + dtls1_stop_timer(s); + s->tlsext_hb_seq++; + s->tlsext_hb_pending = 0; + } + } + + return 0; + } + +int +dtls1_heartbeat(SSL *s) + { + unsigned char *buf, *p; + int ret; + unsigned int payload = 18; /* Sequence number + random bytes */ + unsigned int padding = 16; /* Use minimum padding */ + + /* Only send if peer supports and accepts HB requests... */ + if (!(s->tlsext_heartbeat & SSL_TLSEXT_HB_ENABLED) || + s->tlsext_heartbeat & SSL_TLSEXT_HB_DONT_SEND_REQUESTS) + { + SSLerr(SSL_F_DTLS1_HEARTBEAT,SSL_R_TLS_HEARTBEAT_PEER_DOESNT_ACCEPT); + return -1; + } + + /* ...and there is none in flight yet... */ + if (s->tlsext_hb_pending) + { + SSLerr(SSL_F_DTLS1_HEARTBEAT,SSL_R_TLS_HEARTBEAT_PENDING); + return -1; + } + + /* ...and no handshake in progress. */ + if (SSL_in_init(s) || s->in_handshake) + { + SSLerr(SSL_F_DTLS1_HEARTBEAT,SSL_R_UNEXPECTED_MESSAGE); + return -1; + } + + /* Check if padding is too long, payload and padding + * must not exceed 2^14 - 3 = 16381 bytes in total. + */ + OPENSSL_assert(payload + padding <= 16381); + + /* Create HeartBeat message, we just use a sequence number + * as payload to distuingish different messages and add + * some random stuff. + * - Message Type, 1 byte + * - Payload Length, 2 bytes (unsigned int) + * - Payload, the sequence number (2 bytes uint) + * - Payload, random bytes (16 bytes uint) + * - Padding + */ + buf = OPENSSL_malloc(1 + 2 + payload + padding); + p = buf; + /* Message Type */ + *p++ = TLS1_HB_REQUEST; + /* Payload length (18 bytes here) */ + s2n(payload, p); + /* Sequence number */ + s2n(s->tlsext_hb_seq, p); + /* 16 random bytes */ + RAND_pseudo_bytes(p, 16); + p += 16; + /* Random padding */ + RAND_pseudo_bytes(p, padding); + + ret = dtls1_write_bytes(s, TLS1_RT_HEARTBEAT, buf, 3 + payload + padding); + if (ret >= 0) + { + if (s->msg_callback) + s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT, + buf, 3 + payload + padding, + s, s->msg_callback_arg); + + dtls1_start_timer(s); + s->tlsext_hb_pending = 1; + } + + OPENSSL_free(buf); + + return ret; + } +#endif |