Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 1 | /* ssl/d1_both.c */ |
| 2 | /* |
| 3 | * DTLS implementation written by Nagendra Modadugu |
| 4 | * (nagendra@cs.stanford.edu) for the OpenSSL project 2005. |
| 5 | */ |
| 6 | /* ==================================================================== |
| 7 | * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved. |
| 8 | * |
| 9 | * Redistribution and use in source and binary forms, with or without |
| 10 | * modification, are permitted provided that the following conditions |
| 11 | * are met: |
| 12 | * |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * |
| 16 | * 2. Redistributions in binary form must reproduce the above copyright |
| 17 | * notice, this list of conditions and the following disclaimer in |
| 18 | * the documentation and/or other materials provided with the |
| 19 | * distribution. |
| 20 | * |
| 21 | * 3. All advertising materials mentioning features or use of this |
| 22 | * software must display the following acknowledgment: |
| 23 | * "This product includes software developed by the OpenSSL Project |
| 24 | * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" |
| 25 | * |
| 26 | * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to |
| 27 | * endorse or promote products derived from this software without |
| 28 | * prior written permission. For written permission, please contact |
| 29 | * openssl-core@openssl.org. |
| 30 | * |
| 31 | * 5. Products derived from this software may not be called "OpenSSL" |
| 32 | * nor may "OpenSSL" appear in their names without prior written |
| 33 | * permission of the OpenSSL Project. |
| 34 | * |
| 35 | * 6. Redistributions of any form whatsoever must retain the following |
| 36 | * acknowledgment: |
| 37 | * "This product includes software developed by the OpenSSL Project |
| 38 | * for use in the OpenSSL Toolkit (http://www.openssl.org/)" |
| 39 | * |
| 40 | * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY |
| 41 | * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 42 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 43 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR |
| 44 | * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 45 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 46 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| 47 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 48 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| 49 | * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 50 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
| 51 | * OF THE POSSIBILITY OF SUCH DAMAGE. |
| 52 | * ==================================================================== |
| 53 | * |
| 54 | * This product includes cryptographic software written by Eric Young |
| 55 | * (eay@cryptsoft.com). This product includes software written by Tim |
| 56 | * Hudson (tjh@cryptsoft.com). |
| 57 | * |
| 58 | */ |
| 59 | /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) |
| 60 | * All rights reserved. |
| 61 | * |
| 62 | * This package is an SSL implementation written |
| 63 | * by Eric Young (eay@cryptsoft.com). |
| 64 | * The implementation was written so as to conform with Netscapes SSL. |
| 65 | * |
| 66 | * This library is free for commercial and non-commercial use as long as |
| 67 | * the following conditions are aheared to. The following conditions |
| 68 | * apply to all code found in this distribution, be it the RC4, RSA, |
| 69 | * lhash, DES, etc., code; not just the SSL code. The SSL documentation |
| 70 | * included with this distribution is covered by the same copyright terms |
| 71 | * except that the holder is Tim Hudson (tjh@cryptsoft.com). |
| 72 | * |
| 73 | * Copyright remains Eric Young's, and as such any Copyright notices in |
| 74 | * the code are not to be removed. |
| 75 | * If this package is used in a product, Eric Young should be given attribution |
| 76 | * as the author of the parts of the library used. |
| 77 | * This can be in the form of a textual message at program startup or |
| 78 | * in documentation (online or textual) provided with the package. |
| 79 | * |
| 80 | * Redistribution and use in source and binary forms, with or without |
| 81 | * modification, are permitted provided that the following conditions |
| 82 | * are met: |
| 83 | * 1. Redistributions of source code must retain the copyright |
| 84 | * notice, this list of conditions and the following disclaimer. |
| 85 | * 2. Redistributions in binary form must reproduce the above copyright |
| 86 | * notice, this list of conditions and the following disclaimer in the |
| 87 | * documentation and/or other materials provided with the distribution. |
| 88 | * 3. All advertising materials mentioning features or use of this software |
| 89 | * must display the following acknowledgement: |
| 90 | * "This product includes cryptographic software written by |
| 91 | * Eric Young (eay@cryptsoft.com)" |
| 92 | * The word 'cryptographic' can be left out if the rouines from the library |
| 93 | * being used are not cryptographic related :-). |
| 94 | * 4. If you include any Windows specific code (or a derivative thereof) from |
| 95 | * the apps directory (application code) you must include an acknowledgement: |
| 96 | * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" |
| 97 | * |
| 98 | * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND |
| 99 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 100 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 101 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| 102 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 103 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 104 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 105 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 106 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 107 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 108 | * SUCH DAMAGE. |
| 109 | * |
| 110 | * The licence and distribution terms for any publically available version or |
| 111 | * derivative of this code cannot be changed. i.e. this code cannot simply be |
| 112 | * copied and put under another distribution licence |
| 113 | * [including the GNU Public Licence.] |
| 114 | */ |
| 115 | |
| 116 | #include <limits.h> |
| 117 | #include <string.h> |
| 118 | #include <stdio.h> |
| 119 | #include "ssl_locl.h" |
| 120 | #include <openssl/buffer.h> |
| 121 | #include <openssl/rand.h> |
| 122 | #include <openssl/objects.h> |
| 123 | #include <openssl/evp.h> |
| 124 | #include <openssl/x509.h> |
| 125 | |
| 126 | #define RSMBLY_BITMASK_SIZE(msg_len) (((msg_len) + 7) / 8) |
| 127 | |
| 128 | #define RSMBLY_BITMASK_MARK(bitmask, start, end) { \ |
| 129 | if ((end) - (start) <= 8) { \ |
| 130 | long ii; \ |
| 131 | for (ii = (start); ii < (end); ii++) bitmask[((ii) >> 3)] |= (1 << ((ii) & 7)); \ |
| 132 | } else { \ |
| 133 | long ii; \ |
| 134 | bitmask[((start) >> 3)] |= bitmask_start_values[((start) & 7)]; \ |
| 135 | for (ii = (((start) >> 3) + 1); ii < ((((end) - 1)) >> 3); ii++) bitmask[ii] = 0xff; \ |
| 136 | bitmask[(((end) - 1) >> 3)] |= bitmask_end_values[((end) & 7)]; \ |
| 137 | } } |
| 138 | |
| 139 | #define RSMBLY_BITMASK_IS_COMPLETE(bitmask, msg_len, is_complete) { \ |
| 140 | long ii; \ |
| 141 | OPENSSL_assert((msg_len) > 0); \ |
| 142 | is_complete = 1; \ |
| 143 | if (bitmask[(((msg_len) - 1) >> 3)] != bitmask_end_values[((msg_len) & 7)]) is_complete = 0; \ |
| 144 | if (is_complete) for (ii = (((msg_len) - 1) >> 3) - 1; ii >= 0 ; ii--) \ |
| 145 | if (bitmask[ii] != 0xff) { is_complete = 0; break; } } |
| 146 | |
| 147 | #if 0 |
| 148 | #define RSMBLY_BITMASK_PRINT(bitmask, msg_len) { \ |
| 149 | long ii; \ |
| 150 | printf("bitmask: "); for (ii = 0; ii < (msg_len); ii++) \ |
| 151 | printf("%d ", (bitmask[ii >> 3] & (1 << (ii & 7))) >> (ii & 7)); \ |
| 152 | printf("\n"); } |
| 153 | #endif |
| 154 | |
| 155 | static unsigned char bitmask_start_values[] = {0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80}; |
| 156 | static unsigned char bitmask_end_values[] = {0xff, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f}; |
| 157 | |
| 158 | /* XDTLS: figure out the right values */ |
| 159 | static unsigned int g_probable_mtu[] = {1500 - 28, 512 - 28, 256 - 28}; |
| 160 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 161 | static unsigned int dtls1_min_mtu(void); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 162 | static unsigned int dtls1_guess_mtu(unsigned int curr_mtu); |
| 163 | static void dtls1_fix_message_header(SSL *s, unsigned long frag_off, |
| 164 | unsigned long frag_len); |
| 165 | static unsigned char *dtls1_write_message_header(SSL *s, |
| 166 | unsigned char *p); |
| 167 | static void dtls1_set_message_header_int(SSL *s, unsigned char mt, |
| 168 | unsigned long len, unsigned short seq_num, unsigned long frag_off, |
| 169 | unsigned long frag_len); |
| 170 | static long dtls1_get_message_fragment(SSL *s, int st1, int stn, |
| 171 | long max, int *ok); |
| 172 | |
| 173 | static hm_fragment * |
| 174 | dtls1_hm_fragment_new(unsigned long frag_len, int reassembly) |
| 175 | { |
| 176 | hm_fragment *frag = NULL; |
| 177 | unsigned char *buf = NULL; |
| 178 | unsigned char *bitmask = NULL; |
| 179 | |
| 180 | frag = (hm_fragment *)OPENSSL_malloc(sizeof(hm_fragment)); |
| 181 | if ( frag == NULL) |
| 182 | return NULL; |
| 183 | |
| 184 | if (frag_len) |
| 185 | { |
| 186 | buf = (unsigned char *)OPENSSL_malloc(frag_len); |
| 187 | if ( buf == NULL) |
| 188 | { |
| 189 | OPENSSL_free(frag); |
| 190 | return NULL; |
| 191 | } |
| 192 | } |
| 193 | |
| 194 | /* zero length fragment gets zero frag->fragment */ |
| 195 | frag->fragment = buf; |
| 196 | |
| 197 | /* Initialize reassembly bitmask if necessary */ |
| 198 | if (reassembly) |
| 199 | { |
| 200 | bitmask = (unsigned char *)OPENSSL_malloc(RSMBLY_BITMASK_SIZE(frag_len)); |
| 201 | if (bitmask == NULL) |
| 202 | { |
| 203 | if (buf != NULL) OPENSSL_free(buf); |
| 204 | OPENSSL_free(frag); |
| 205 | return NULL; |
| 206 | } |
| 207 | memset(bitmask, 0, RSMBLY_BITMASK_SIZE(frag_len)); |
| 208 | } |
| 209 | |
| 210 | frag->reassembly = bitmask; |
| 211 | |
| 212 | return frag; |
| 213 | } |
| 214 | |
| 215 | static void |
| 216 | dtls1_hm_fragment_free(hm_fragment *frag) |
| 217 | { |
| 218 | if (frag->fragment) OPENSSL_free(frag->fragment); |
| 219 | if (frag->reassembly) OPENSSL_free(frag->reassembly); |
| 220 | OPENSSL_free(frag); |
| 221 | } |
| 222 | |
| 223 | /* send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or SSL3_RT_CHANGE_CIPHER_SPEC) */ |
| 224 | int dtls1_do_write(SSL *s, int type) |
| 225 | { |
| 226 | int ret; |
| 227 | int curr_mtu; |
| 228 | unsigned int len, frag_off, mac_size, blocksize; |
| 229 | |
| 230 | /* AHA! Figure out the MTU, and stick to the right size */ |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 231 | if ( ! (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)) |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 232 | { |
| 233 | s->d1->mtu = |
| 234 | BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL); |
| 235 | |
| 236 | /* I've seen the kernel return bogus numbers when it doesn't know |
| 237 | * (initial write), so just make sure we have a reasonable number */ |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 238 | if ( s->d1->mtu < dtls1_min_mtu()) |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 239 | { |
| 240 | s->d1->mtu = 0; |
| 241 | s->d1->mtu = dtls1_guess_mtu(s->d1->mtu); |
| 242 | BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SET_MTU, |
| 243 | s->d1->mtu, NULL); |
| 244 | } |
| 245 | } |
| 246 | #if 0 |
| 247 | mtu = s->d1->mtu; |
| 248 | |
| 249 | fprintf(stderr, "using MTU = %d\n", mtu); |
| 250 | |
| 251 | mtu -= (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH); |
| 252 | |
| 253 | curr_mtu = mtu - BIO_wpending(SSL_get_wbio(s)); |
| 254 | |
| 255 | if ( curr_mtu > 0) |
| 256 | mtu = curr_mtu; |
| 257 | else if ( ( ret = BIO_flush(SSL_get_wbio(s))) <= 0) |
| 258 | return ret; |
| 259 | |
| 260 | if ( BIO_wpending(SSL_get_wbio(s)) + s->init_num >= mtu) |
| 261 | { |
| 262 | ret = BIO_flush(SSL_get_wbio(s)); |
| 263 | if ( ret <= 0) |
| 264 | return ret; |
| 265 | mtu = s->d1->mtu - (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH); |
| 266 | } |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 267 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 268 | OPENSSL_assert(mtu > 0); /* should have something reasonable now */ |
| 269 | |
| 270 | #endif |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 271 | |
| 272 | if ( s->init_off == 0 && type == SSL3_RT_HANDSHAKE) |
| 273 | OPENSSL_assert(s->init_num == |
| 274 | (int)s->d1->w_msg_hdr.msg_len + DTLS1_HM_HEADER_LENGTH); |
| 275 | |
| 276 | if (s->write_hash) |
| 277 | mac_size = EVP_MD_CTX_size(s->write_hash); |
| 278 | else |
| 279 | mac_size = 0; |
| 280 | |
| 281 | if (s->enc_write_ctx && |
| 282 | (EVP_CIPHER_mode( s->enc_write_ctx->cipher) & EVP_CIPH_CBC_MODE)) |
| 283 | blocksize = 2 * EVP_CIPHER_block_size(s->enc_write_ctx->cipher); |
| 284 | else |
| 285 | blocksize = 0; |
| 286 | |
| 287 | frag_off = 0; |
| 288 | while( s->init_num) |
| 289 | { |
| 290 | curr_mtu = s->d1->mtu - BIO_wpending(SSL_get_wbio(s)) - |
| 291 | DTLS1_RT_HEADER_LENGTH - mac_size - blocksize; |
| 292 | |
| 293 | if ( curr_mtu <= DTLS1_HM_HEADER_LENGTH) |
| 294 | { |
| 295 | /* grr.. we could get an error if MTU picked was wrong */ |
| 296 | ret = BIO_flush(SSL_get_wbio(s)); |
| 297 | if ( ret <= 0) |
| 298 | return ret; |
| 299 | curr_mtu = s->d1->mtu - DTLS1_RT_HEADER_LENGTH - |
| 300 | mac_size - blocksize; |
| 301 | } |
| 302 | |
| 303 | if ( s->init_num > curr_mtu) |
| 304 | len = curr_mtu; |
| 305 | else |
| 306 | len = s->init_num; |
| 307 | |
| 308 | |
| 309 | /* XDTLS: this function is too long. split out the CCS part */ |
| 310 | if ( type == SSL3_RT_HANDSHAKE) |
| 311 | { |
| 312 | if ( s->init_off != 0) |
| 313 | { |
| 314 | OPENSSL_assert(s->init_off > DTLS1_HM_HEADER_LENGTH); |
| 315 | s->init_off -= DTLS1_HM_HEADER_LENGTH; |
| 316 | s->init_num += DTLS1_HM_HEADER_LENGTH; |
| 317 | |
| 318 | /* write atleast DTLS1_HM_HEADER_LENGTH bytes */ |
| 319 | if ( len <= DTLS1_HM_HEADER_LENGTH) |
| 320 | len += DTLS1_HM_HEADER_LENGTH; |
| 321 | } |
| 322 | |
| 323 | dtls1_fix_message_header(s, frag_off, |
| 324 | len - DTLS1_HM_HEADER_LENGTH); |
| 325 | |
| 326 | dtls1_write_message_header(s, (unsigned char *)&s->init_buf->data[s->init_off]); |
| 327 | |
| 328 | OPENSSL_assert(len >= DTLS1_HM_HEADER_LENGTH); |
| 329 | } |
| 330 | |
| 331 | ret=dtls1_write_bytes(s,type,&s->init_buf->data[s->init_off], |
| 332 | len); |
| 333 | if (ret < 0) |
| 334 | { |
| 335 | /* might need to update MTU here, but we don't know |
| 336 | * which previous packet caused the failure -- so can't |
| 337 | * really retransmit anything. continue as if everything |
| 338 | * is fine and wait for an alert to handle the |
| 339 | * retransmit |
| 340 | */ |
| 341 | if ( BIO_ctrl(SSL_get_wbio(s), |
| 342 | BIO_CTRL_DGRAM_MTU_EXCEEDED, 0, NULL) > 0 ) |
| 343 | s->d1->mtu = BIO_ctrl(SSL_get_wbio(s), |
| 344 | BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL); |
| 345 | else |
| 346 | return(-1); |
| 347 | } |
| 348 | else |
| 349 | { |
| 350 | |
| 351 | /* bad if this assert fails, only part of the handshake |
| 352 | * message got sent. but why would this happen? */ |
| 353 | OPENSSL_assert(len == (unsigned int)ret); |
| 354 | |
| 355 | if (type == SSL3_RT_HANDSHAKE && ! s->d1->retransmitting) |
| 356 | { |
| 357 | /* should not be done for 'Hello Request's, but in that case |
| 358 | * we'll ignore the result anyway */ |
| 359 | unsigned char *p = (unsigned char *)&s->init_buf->data[s->init_off]; |
| 360 | const struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; |
| 361 | int xlen; |
| 362 | |
| 363 | if (frag_off == 0 && s->version != DTLS1_BAD_VER) |
| 364 | { |
| 365 | /* reconstruct message header is if it |
| 366 | * is being sent in single fragment */ |
| 367 | *p++ = msg_hdr->type; |
| 368 | l2n3(msg_hdr->msg_len,p); |
| 369 | s2n (msg_hdr->seq,p); |
| 370 | l2n3(0,p); |
| 371 | l2n3(msg_hdr->msg_len,p); |
| 372 | p -= DTLS1_HM_HEADER_LENGTH; |
| 373 | xlen = ret; |
| 374 | } |
| 375 | else |
| 376 | { |
| 377 | p += DTLS1_HM_HEADER_LENGTH; |
| 378 | xlen = ret - DTLS1_HM_HEADER_LENGTH; |
| 379 | } |
| 380 | |
| 381 | ssl3_finish_mac(s, p, xlen); |
| 382 | } |
| 383 | |
| 384 | if (ret == s->init_num) |
| 385 | { |
| 386 | if (s->msg_callback) |
| 387 | s->msg_callback(1, s->version, type, s->init_buf->data, |
| 388 | (size_t)(s->init_off + s->init_num), s, |
| 389 | s->msg_callback_arg); |
| 390 | |
| 391 | s->init_off = 0; /* done writing this message */ |
| 392 | s->init_num = 0; |
| 393 | |
| 394 | return(1); |
| 395 | } |
| 396 | s->init_off+=ret; |
| 397 | s->init_num-=ret; |
| 398 | frag_off += (ret -= DTLS1_HM_HEADER_LENGTH); |
| 399 | } |
| 400 | } |
| 401 | return(0); |
| 402 | } |
| 403 | |
| 404 | |
| 405 | /* Obtain handshake message of message type 'mt' (any if mt == -1), |
| 406 | * maximum acceptable body length 'max'. |
| 407 | * Read an entire handshake message. Handshake messages arrive in |
| 408 | * fragments. |
| 409 | */ |
| 410 | long dtls1_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok) |
| 411 | { |
| 412 | int i, al; |
| 413 | struct hm_header_st *msg_hdr; |
| 414 | unsigned char *p; |
| 415 | unsigned long msg_len; |
| 416 | |
| 417 | /* s3->tmp is used to store messages that are unexpected, caused |
| 418 | * by the absence of an optional handshake message */ |
| 419 | if (s->s3->tmp.reuse_message) |
| 420 | { |
| 421 | s->s3->tmp.reuse_message=0; |
| 422 | if ((mt >= 0) && (s->s3->tmp.message_type != mt)) |
| 423 | { |
| 424 | al=SSL_AD_UNEXPECTED_MESSAGE; |
| 425 | SSLerr(SSL_F_DTLS1_GET_MESSAGE,SSL_R_UNEXPECTED_MESSAGE); |
| 426 | goto f_err; |
| 427 | } |
| 428 | *ok=1; |
| 429 | s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH; |
| 430 | s->init_num = (int)s->s3->tmp.message_size; |
| 431 | return s->init_num; |
| 432 | } |
| 433 | |
| 434 | msg_hdr = &s->d1->r_msg_hdr; |
| 435 | memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); |
| 436 | |
| 437 | again: |
| 438 | i = dtls1_get_message_fragment(s, st1, stn, max, ok); |
| 439 | if ( i == DTLS1_HM_BAD_FRAGMENT || |
| 440 | i == DTLS1_HM_FRAGMENT_RETRY) /* bad fragment received */ |
| 441 | goto again; |
| 442 | else if ( i <= 0 && !*ok) |
| 443 | return i; |
| 444 | |
| 445 | p = (unsigned char *)s->init_buf->data; |
| 446 | msg_len = msg_hdr->msg_len; |
| 447 | |
| 448 | /* reconstruct message header */ |
| 449 | *(p++) = msg_hdr->type; |
| 450 | l2n3(msg_len,p); |
| 451 | s2n (msg_hdr->seq,p); |
| 452 | l2n3(0,p); |
| 453 | l2n3(msg_len,p); |
| 454 | if (s->version != DTLS1_BAD_VER) { |
| 455 | p -= DTLS1_HM_HEADER_LENGTH; |
| 456 | msg_len += DTLS1_HM_HEADER_LENGTH; |
| 457 | } |
| 458 | |
| 459 | ssl3_finish_mac(s, p, msg_len); |
| 460 | if (s->msg_callback) |
| 461 | s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, |
| 462 | p, msg_len, |
| 463 | s, s->msg_callback_arg); |
| 464 | |
| 465 | memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); |
| 466 | |
| 467 | /* Don't change sequence numbers while listening */ |
| 468 | if (!s->d1->listen) |
| 469 | s->d1->handshake_read_seq++; |
| 470 | |
| 471 | s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH; |
| 472 | return s->init_num; |
| 473 | |
| 474 | f_err: |
| 475 | ssl3_send_alert(s,SSL3_AL_FATAL,al); |
| 476 | *ok = 0; |
| 477 | return -1; |
| 478 | } |
| 479 | |
| 480 | |
| 481 | static int dtls1_preprocess_fragment(SSL *s,struct hm_header_st *msg_hdr,int max) |
| 482 | { |
| 483 | size_t frag_off,frag_len,msg_len; |
| 484 | |
| 485 | msg_len = msg_hdr->msg_len; |
| 486 | frag_off = msg_hdr->frag_off; |
| 487 | frag_len = msg_hdr->frag_len; |
| 488 | |
| 489 | /* sanity checking */ |
| 490 | if ( (frag_off+frag_len) > msg_len) |
| 491 | { |
| 492 | SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE); |
| 493 | return SSL_AD_ILLEGAL_PARAMETER; |
| 494 | } |
| 495 | |
| 496 | if ( (frag_off+frag_len) > (unsigned long)max) |
| 497 | { |
| 498 | SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE); |
| 499 | return SSL_AD_ILLEGAL_PARAMETER; |
| 500 | } |
| 501 | |
| 502 | if ( s->d1->r_msg_hdr.frag_off == 0) /* first fragment */ |
| 503 | { |
| 504 | /* msg_len is limited to 2^24, but is effectively checked |
| 505 | * against max above */ |
| 506 | if (!BUF_MEM_grow_clean(s->init_buf,msg_len+DTLS1_HM_HEADER_LENGTH)) |
| 507 | { |
| 508 | SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,ERR_R_BUF_LIB); |
| 509 | return SSL_AD_INTERNAL_ERROR; |
| 510 | } |
| 511 | |
| 512 | s->s3->tmp.message_size = msg_len; |
| 513 | s->d1->r_msg_hdr.msg_len = msg_len; |
| 514 | s->s3->tmp.message_type = msg_hdr->type; |
| 515 | s->d1->r_msg_hdr.type = msg_hdr->type; |
| 516 | s->d1->r_msg_hdr.seq = msg_hdr->seq; |
| 517 | } |
| 518 | else if (msg_len != s->d1->r_msg_hdr.msg_len) |
| 519 | { |
| 520 | /* They must be playing with us! BTW, failure to enforce |
| 521 | * upper limit would open possibility for buffer overrun. */ |
| 522 | SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE); |
| 523 | return SSL_AD_ILLEGAL_PARAMETER; |
| 524 | } |
| 525 | |
| 526 | return 0; /* no error */ |
| 527 | } |
| 528 | |
| 529 | |
| 530 | static int |
| 531 | dtls1_retrieve_buffered_fragment(SSL *s, long max, int *ok) |
| 532 | { |
| 533 | /* (0) check whether the desired fragment is available |
| 534 | * if so: |
| 535 | * (1) copy over the fragment to s->init_buf->data[] |
| 536 | * (2) update s->init_num |
| 537 | */ |
| 538 | pitem *item; |
| 539 | hm_fragment *frag; |
| 540 | int al; |
| 541 | |
| 542 | *ok = 0; |
| 543 | item = pqueue_peek(s->d1->buffered_messages); |
| 544 | if ( item == NULL) |
| 545 | return 0; |
| 546 | |
| 547 | frag = (hm_fragment *)item->data; |
| 548 | |
| 549 | /* Don't return if reassembly still in progress */ |
| 550 | if (frag->reassembly != NULL) |
| 551 | return 0; |
| 552 | |
| 553 | if ( s->d1->handshake_read_seq == frag->msg_header.seq) |
| 554 | { |
| 555 | unsigned long frag_len = frag->msg_header.frag_len; |
| 556 | pqueue_pop(s->d1->buffered_messages); |
| 557 | |
| 558 | al=dtls1_preprocess_fragment(s,&frag->msg_header,max); |
| 559 | |
| 560 | if (al==0) /* no alert */ |
| 561 | { |
| 562 | unsigned char *p = (unsigned char *)s->init_buf->data+DTLS1_HM_HEADER_LENGTH; |
| 563 | memcpy(&p[frag->msg_header.frag_off], |
| 564 | frag->fragment,frag->msg_header.frag_len); |
| 565 | } |
| 566 | |
| 567 | dtls1_hm_fragment_free(frag); |
| 568 | pitem_free(item); |
| 569 | |
| 570 | if (al==0) |
| 571 | { |
| 572 | *ok = 1; |
| 573 | return frag_len; |
| 574 | } |
| 575 | |
| 576 | ssl3_send_alert(s,SSL3_AL_FATAL,al); |
| 577 | s->init_num = 0; |
| 578 | *ok = 0; |
| 579 | return -1; |
| 580 | } |
| 581 | else |
| 582 | return 0; |
| 583 | } |
| 584 | |
| 585 | |
| 586 | static int |
| 587 | dtls1_reassemble_fragment(SSL *s, struct hm_header_st* msg_hdr, int *ok) |
| 588 | { |
| 589 | hm_fragment *frag = NULL; |
| 590 | pitem *item = NULL; |
| 591 | int i = -1, is_complete; |
| 592 | unsigned char seq64be[8]; |
| 593 | unsigned long frag_len = msg_hdr->frag_len, max_len; |
| 594 | |
| 595 | if ((msg_hdr->frag_off+frag_len) > msg_hdr->msg_len) |
| 596 | goto err; |
| 597 | |
| 598 | /* Determine maximum allowed message size. Depends on (user set) |
| 599 | * maximum certificate length, but 16k is minimum. |
| 600 | */ |
| 601 | if (DTLS1_HM_HEADER_LENGTH + SSL3_RT_MAX_ENCRYPTED_LENGTH < s->max_cert_list) |
| 602 | max_len = s->max_cert_list; |
| 603 | else |
| 604 | max_len = DTLS1_HM_HEADER_LENGTH + SSL3_RT_MAX_ENCRYPTED_LENGTH; |
| 605 | |
| 606 | if ((msg_hdr->frag_off+frag_len) > max_len) |
| 607 | goto err; |
| 608 | |
| 609 | /* Try to find item in queue */ |
| 610 | memset(seq64be,0,sizeof(seq64be)); |
| 611 | seq64be[6] = (unsigned char) (msg_hdr->seq>>8); |
| 612 | seq64be[7] = (unsigned char) msg_hdr->seq; |
| 613 | item = pqueue_find(s->d1->buffered_messages, seq64be); |
| 614 | |
| 615 | if (item == NULL) |
| 616 | { |
| 617 | frag = dtls1_hm_fragment_new(msg_hdr->msg_len, 1); |
| 618 | if ( frag == NULL) |
| 619 | goto err; |
| 620 | memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); |
| 621 | frag->msg_header.frag_len = frag->msg_header.msg_len; |
| 622 | frag->msg_header.frag_off = 0; |
| 623 | } |
| 624 | else |
| 625 | frag = (hm_fragment*) item->data; |
| 626 | |
| 627 | /* If message is already reassembled, this must be a |
| 628 | * retransmit and can be dropped. |
| 629 | */ |
| 630 | if (frag->reassembly == NULL) |
| 631 | { |
| 632 | unsigned char devnull [256]; |
| 633 | |
| 634 | while (frag_len) |
| 635 | { |
| 636 | i = s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE, |
| 637 | devnull, |
| 638 | frag_len>sizeof(devnull)?sizeof(devnull):frag_len,0); |
| 639 | if (i<=0) goto err; |
| 640 | frag_len -= i; |
| 641 | } |
| 642 | return DTLS1_HM_FRAGMENT_RETRY; |
| 643 | } |
| 644 | |
| 645 | /* read the body of the fragment (header has already been read */ |
| 646 | i = s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE, |
| 647 | frag->fragment + msg_hdr->frag_off,frag_len,0); |
| 648 | if (i<=0 || (unsigned long)i!=frag_len) |
| 649 | goto err; |
| 650 | |
| 651 | RSMBLY_BITMASK_MARK(frag->reassembly, (long)msg_hdr->frag_off, |
| 652 | (long)(msg_hdr->frag_off + frag_len)); |
| 653 | |
| 654 | RSMBLY_BITMASK_IS_COMPLETE(frag->reassembly, (long)msg_hdr->msg_len, |
| 655 | is_complete); |
| 656 | |
| 657 | if (is_complete) |
| 658 | { |
| 659 | OPENSSL_free(frag->reassembly); |
| 660 | frag->reassembly = NULL; |
| 661 | } |
| 662 | |
| 663 | if (item == NULL) |
| 664 | { |
| 665 | memset(seq64be,0,sizeof(seq64be)); |
| 666 | seq64be[6] = (unsigned char)(msg_hdr->seq>>8); |
| 667 | seq64be[7] = (unsigned char)(msg_hdr->seq); |
| 668 | |
| 669 | item = pitem_new(seq64be, frag); |
| 670 | if (item == NULL) |
| 671 | { |
| 672 | goto err; |
| 673 | i = -1; |
| 674 | } |
| 675 | |
| 676 | pqueue_insert(s->d1->buffered_messages, item); |
| 677 | } |
| 678 | |
| 679 | return DTLS1_HM_FRAGMENT_RETRY; |
| 680 | |
| 681 | err: |
| 682 | if (frag != NULL) dtls1_hm_fragment_free(frag); |
| 683 | if (item != NULL) OPENSSL_free(item); |
| 684 | *ok = 0; |
| 685 | return i; |
| 686 | } |
| 687 | |
| 688 | |
| 689 | static int |
| 690 | dtls1_process_out_of_seq_message(SSL *s, struct hm_header_st* msg_hdr, int *ok) |
| 691 | { |
| 692 | int i=-1; |
| 693 | hm_fragment *frag = NULL; |
| 694 | pitem *item = NULL; |
| 695 | unsigned char seq64be[8]; |
| 696 | unsigned long frag_len = msg_hdr->frag_len; |
| 697 | |
| 698 | if ((msg_hdr->frag_off+frag_len) > msg_hdr->msg_len) |
| 699 | goto err; |
| 700 | |
| 701 | /* Try to find item in queue, to prevent duplicate entries */ |
| 702 | memset(seq64be,0,sizeof(seq64be)); |
| 703 | seq64be[6] = (unsigned char) (msg_hdr->seq>>8); |
| 704 | seq64be[7] = (unsigned char) msg_hdr->seq; |
| 705 | item = pqueue_find(s->d1->buffered_messages, seq64be); |
| 706 | |
| 707 | /* If we already have an entry and this one is a fragment, |
| 708 | * don't discard it and rather try to reassemble it. |
| 709 | */ |
| 710 | if (item != NULL && frag_len < msg_hdr->msg_len) |
| 711 | item = NULL; |
| 712 | |
| 713 | /* Discard the message if sequence number was already there, is |
| 714 | * too far in the future, already in the queue or if we received |
| 715 | * a FINISHED before the SERVER_HELLO, which then must be a stale |
| 716 | * retransmit. |
| 717 | */ |
| 718 | if (msg_hdr->seq <= s->d1->handshake_read_seq || |
| 719 | msg_hdr->seq > s->d1->handshake_read_seq + 10 || item != NULL || |
| 720 | (s->d1->handshake_read_seq == 0 && msg_hdr->type == SSL3_MT_FINISHED)) |
| 721 | { |
| 722 | unsigned char devnull [256]; |
| 723 | |
| 724 | while (frag_len) |
| 725 | { |
| 726 | i = s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE, |
| 727 | devnull, |
| 728 | frag_len>sizeof(devnull)?sizeof(devnull):frag_len,0); |
| 729 | if (i<=0) goto err; |
| 730 | frag_len -= i; |
| 731 | } |
| 732 | } |
| 733 | else |
| 734 | { |
| 735 | if (frag_len && frag_len < msg_hdr->msg_len) |
| 736 | return dtls1_reassemble_fragment(s, msg_hdr, ok); |
| 737 | |
| 738 | frag = dtls1_hm_fragment_new(frag_len, 0); |
| 739 | if ( frag == NULL) |
| 740 | goto err; |
| 741 | |
| 742 | memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); |
| 743 | |
| 744 | if (frag_len) |
| 745 | { |
| 746 | /* read the body of the fragment (header has already been read */ |
| 747 | i = s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE, |
| 748 | frag->fragment,frag_len,0); |
| 749 | if (i<=0 || (unsigned long)i!=frag_len) |
| 750 | goto err; |
| 751 | } |
| 752 | |
| 753 | memset(seq64be,0,sizeof(seq64be)); |
| 754 | seq64be[6] = (unsigned char)(msg_hdr->seq>>8); |
| 755 | seq64be[7] = (unsigned char)(msg_hdr->seq); |
| 756 | |
| 757 | item = pitem_new(seq64be, frag); |
| 758 | if ( item == NULL) |
| 759 | goto err; |
| 760 | |
| 761 | pqueue_insert(s->d1->buffered_messages, item); |
| 762 | } |
| 763 | |
| 764 | return DTLS1_HM_FRAGMENT_RETRY; |
| 765 | |
| 766 | err: |
| 767 | if ( frag != NULL) dtls1_hm_fragment_free(frag); |
| 768 | if ( item != NULL) OPENSSL_free(item); |
| 769 | *ok = 0; |
| 770 | return i; |
| 771 | } |
| 772 | |
| 773 | |
| 774 | static long |
| 775 | dtls1_get_message_fragment(SSL *s, int st1, int stn, long max, int *ok) |
| 776 | { |
| 777 | unsigned char wire[DTLS1_HM_HEADER_LENGTH]; |
| 778 | unsigned long len, frag_off, frag_len; |
| 779 | int i,al; |
| 780 | struct hm_header_st msg_hdr; |
| 781 | |
| 782 | /* see if we have the required fragment already */ |
| 783 | if ((frag_len = dtls1_retrieve_buffered_fragment(s,max,ok)) || *ok) |
| 784 | { |
| 785 | if (*ok) s->init_num = frag_len; |
| 786 | return frag_len; |
| 787 | } |
| 788 | |
| 789 | /* read handshake message header */ |
| 790 | i=s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,wire, |
| 791 | DTLS1_HM_HEADER_LENGTH, 0); |
| 792 | if (i <= 0) /* nbio, or an error */ |
| 793 | { |
| 794 | s->rwstate=SSL_READING; |
| 795 | *ok = 0; |
| 796 | return i; |
| 797 | } |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 798 | OPENSSL_assert(i == DTLS1_HM_HEADER_LENGTH); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 799 | |
| 800 | /* parse the message fragment header */ |
| 801 | dtls1_get_message_header(wire, &msg_hdr); |
| 802 | |
| 803 | /* |
| 804 | * if this is a future (or stale) message it gets buffered |
| 805 | * (or dropped)--no further processing at this time |
| 806 | * While listening, we accept seq 1 (ClientHello with cookie) |
| 807 | * although we're still expecting seq 0 (ClientHello) |
| 808 | */ |
| 809 | if (msg_hdr.seq != s->d1->handshake_read_seq && !(s->d1->listen && msg_hdr.seq == 1)) |
| 810 | return dtls1_process_out_of_seq_message(s, &msg_hdr, ok); |
| 811 | |
| 812 | len = msg_hdr.msg_len; |
| 813 | frag_off = msg_hdr.frag_off; |
| 814 | frag_len = msg_hdr.frag_len; |
| 815 | |
| 816 | if (frag_len && frag_len < len) |
| 817 | return dtls1_reassemble_fragment(s, &msg_hdr, ok); |
| 818 | |
| 819 | if (!s->server && s->d1->r_msg_hdr.frag_off == 0 && |
| 820 | wire[0] == SSL3_MT_HELLO_REQUEST) |
| 821 | { |
| 822 | /* The server may always send 'Hello Request' messages -- |
| 823 | * we are doing a handshake anyway now, so ignore them |
| 824 | * if their format is correct. Does not count for |
| 825 | * 'Finished' MAC. */ |
| 826 | if (wire[1] == 0 && wire[2] == 0 && wire[3] == 0) |
| 827 | { |
| 828 | if (s->msg_callback) |
| 829 | s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, |
| 830 | wire, DTLS1_HM_HEADER_LENGTH, s, |
| 831 | s->msg_callback_arg); |
| 832 | |
| 833 | s->init_num = 0; |
| 834 | return dtls1_get_message_fragment(s, st1, stn, |
| 835 | max, ok); |
| 836 | } |
| 837 | else /* Incorrectly formated Hello request */ |
| 838 | { |
| 839 | al=SSL_AD_UNEXPECTED_MESSAGE; |
| 840 | SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,SSL_R_UNEXPECTED_MESSAGE); |
| 841 | goto f_err; |
| 842 | } |
| 843 | } |
| 844 | |
| 845 | if ((al=dtls1_preprocess_fragment(s,&msg_hdr,max))) |
| 846 | goto f_err; |
| 847 | |
| 848 | /* XDTLS: ressurect this when restart is in place */ |
| 849 | s->state=stn; |
| 850 | |
| 851 | if ( frag_len > 0) |
| 852 | { |
| 853 | unsigned char *p=(unsigned char *)s->init_buf->data+DTLS1_HM_HEADER_LENGTH; |
| 854 | |
| 855 | i=s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE, |
| 856 | &p[frag_off],frag_len,0); |
| 857 | /* XDTLS: fix this--message fragments cannot span multiple packets */ |
| 858 | if (i <= 0) |
| 859 | { |
| 860 | s->rwstate=SSL_READING; |
| 861 | *ok = 0; |
| 862 | return i; |
| 863 | } |
| 864 | } |
| 865 | else |
| 866 | i = 0; |
| 867 | |
| 868 | /* XDTLS: an incorrectly formatted fragment should cause the |
| 869 | * handshake to fail */ |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 870 | OPENSSL_assert(i == (int)frag_len); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 871 | |
| 872 | *ok = 1; |
| 873 | |
| 874 | /* Note that s->init_num is *not* used as current offset in |
| 875 | * s->init_buf->data, but as a counter summing up fragments' |
| 876 | * lengths: as soon as they sum up to handshake packet |
| 877 | * length, we assume we have got all the fragments. */ |
| 878 | s->init_num = frag_len; |
| 879 | return frag_len; |
| 880 | |
| 881 | f_err: |
| 882 | ssl3_send_alert(s,SSL3_AL_FATAL,al); |
| 883 | s->init_num = 0; |
| 884 | |
| 885 | *ok=0; |
| 886 | return(-1); |
| 887 | } |
| 888 | |
| 889 | int dtls1_send_finished(SSL *s, int a, int b, const char *sender, int slen) |
| 890 | { |
| 891 | unsigned char *p,*d; |
| 892 | int i; |
| 893 | unsigned long l; |
| 894 | |
| 895 | if (s->state == a) |
| 896 | { |
| 897 | d=(unsigned char *)s->init_buf->data; |
| 898 | p= &(d[DTLS1_HM_HEADER_LENGTH]); |
| 899 | |
| 900 | i=s->method->ssl3_enc->final_finish_mac(s, |
| 901 | sender,slen,s->s3->tmp.finish_md); |
| 902 | s->s3->tmp.finish_md_len = i; |
| 903 | memcpy(p, s->s3->tmp.finish_md, i); |
| 904 | p+=i; |
| 905 | l=i; |
| 906 | |
| 907 | /* Copy the finished so we can use it for |
| 908 | * renegotiation checks |
| 909 | */ |
| 910 | if(s->type == SSL_ST_CONNECT) |
| 911 | { |
| 912 | OPENSSL_assert(i <= EVP_MAX_MD_SIZE); |
| 913 | memcpy(s->s3->previous_client_finished, |
| 914 | s->s3->tmp.finish_md, i); |
| 915 | s->s3->previous_client_finished_len=i; |
| 916 | } |
| 917 | else |
| 918 | { |
| 919 | OPENSSL_assert(i <= EVP_MAX_MD_SIZE); |
| 920 | memcpy(s->s3->previous_server_finished, |
| 921 | s->s3->tmp.finish_md, i); |
| 922 | s->s3->previous_server_finished_len=i; |
| 923 | } |
| 924 | |
| 925 | #ifdef OPENSSL_SYS_WIN16 |
| 926 | /* MSVC 1.5 does not clear the top bytes of the word unless |
| 927 | * I do this. |
| 928 | */ |
| 929 | l&=0xffff; |
| 930 | #endif |
| 931 | |
| 932 | d = dtls1_set_message_header(s, d, SSL3_MT_FINISHED, l, 0, l); |
| 933 | s->init_num=(int)l+DTLS1_HM_HEADER_LENGTH; |
| 934 | s->init_off=0; |
| 935 | |
| 936 | /* buffer the message to handle re-xmits */ |
| 937 | dtls1_buffer_message(s, 0); |
| 938 | |
| 939 | s->state=b; |
| 940 | } |
| 941 | |
| 942 | /* SSL3_ST_SEND_xxxxxx_HELLO_B */ |
| 943 | return(dtls1_do_write(s,SSL3_RT_HANDSHAKE)); |
| 944 | } |
| 945 | |
| 946 | /* for these 2 messages, we need to |
| 947 | * ssl->enc_read_ctx re-init |
| 948 | * ssl->s3->read_sequence zero |
| 949 | * ssl->s3->read_mac_secret re-init |
| 950 | * ssl->session->read_sym_enc assign |
| 951 | * ssl->session->read_compression assign |
| 952 | * ssl->session->read_hash assign |
| 953 | */ |
| 954 | int dtls1_send_change_cipher_spec(SSL *s, int a, int b) |
| 955 | { |
| 956 | unsigned char *p; |
| 957 | |
| 958 | if (s->state == a) |
| 959 | { |
| 960 | p=(unsigned char *)s->init_buf->data; |
| 961 | *p++=SSL3_MT_CCS; |
| 962 | s->d1->handshake_write_seq = s->d1->next_handshake_write_seq; |
| 963 | s->init_num=DTLS1_CCS_HEADER_LENGTH; |
| 964 | |
| 965 | if (s->version == DTLS1_BAD_VER) { |
| 966 | s->d1->next_handshake_write_seq++; |
| 967 | s2n(s->d1->handshake_write_seq,p); |
| 968 | s->init_num+=2; |
| 969 | } |
| 970 | |
| 971 | s->init_off=0; |
| 972 | |
| 973 | dtls1_set_message_header_int(s, SSL3_MT_CCS, 0, |
| 974 | s->d1->handshake_write_seq, 0, 0); |
| 975 | |
| 976 | /* buffer the message to handle re-xmits */ |
| 977 | dtls1_buffer_message(s, 1); |
| 978 | |
| 979 | s->state=b; |
| 980 | } |
| 981 | |
| 982 | /* SSL3_ST_CW_CHANGE_B */ |
| 983 | return(dtls1_do_write(s,SSL3_RT_CHANGE_CIPHER_SPEC)); |
| 984 | } |
| 985 | |
| 986 | static int dtls1_add_cert_to_buf(BUF_MEM *buf, unsigned long *l, X509 *x) |
| 987 | { |
| 988 | int n; |
| 989 | unsigned char *p; |
| 990 | |
| 991 | n=i2d_X509(x,NULL); |
| 992 | if (!BUF_MEM_grow_clean(buf,(int)(n+(*l)+3))) |
| 993 | { |
| 994 | SSLerr(SSL_F_DTLS1_ADD_CERT_TO_BUF,ERR_R_BUF_LIB); |
| 995 | return 0; |
| 996 | } |
| 997 | p=(unsigned char *)&(buf->data[*l]); |
| 998 | l2n3(n,p); |
| 999 | i2d_X509(x,&p); |
| 1000 | *l+=n+3; |
| 1001 | |
| 1002 | return 1; |
| 1003 | } |
| 1004 | unsigned long dtls1_output_cert_chain(SSL *s, X509 *x) |
| 1005 | { |
| 1006 | unsigned char *p; |
| 1007 | int i; |
| 1008 | unsigned long l= 3 + DTLS1_HM_HEADER_LENGTH; |
| 1009 | BUF_MEM *buf; |
| 1010 | |
| 1011 | /* TLSv1 sends a chain with nothing in it, instead of an alert */ |
| 1012 | buf=s->init_buf; |
| 1013 | if (!BUF_MEM_grow_clean(buf,10)) |
| 1014 | { |
| 1015 | SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_BUF_LIB); |
| 1016 | return(0); |
| 1017 | } |
| 1018 | if (x != NULL) |
| 1019 | { |
| 1020 | X509_STORE_CTX xs_ctx; |
| 1021 | |
| 1022 | if (!X509_STORE_CTX_init(&xs_ctx,s->ctx->cert_store,x,NULL)) |
| 1023 | { |
| 1024 | SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_X509_LIB); |
| 1025 | return(0); |
| 1026 | } |
| 1027 | |
| 1028 | X509_verify_cert(&xs_ctx); |
| 1029 | /* Don't leave errors in the queue */ |
| 1030 | ERR_clear_error(); |
| 1031 | for (i=0; i < sk_X509_num(xs_ctx.chain); i++) |
| 1032 | { |
| 1033 | x = sk_X509_value(xs_ctx.chain, i); |
| 1034 | |
| 1035 | if (!dtls1_add_cert_to_buf(buf, &l, x)) |
| 1036 | { |
| 1037 | X509_STORE_CTX_cleanup(&xs_ctx); |
| 1038 | return 0; |
| 1039 | } |
| 1040 | } |
| 1041 | X509_STORE_CTX_cleanup(&xs_ctx); |
| 1042 | } |
| 1043 | /* Thawte special :-) */ |
| 1044 | for (i=0; i<sk_X509_num(s->ctx->extra_certs); i++) |
| 1045 | { |
| 1046 | x=sk_X509_value(s->ctx->extra_certs,i); |
| 1047 | if (!dtls1_add_cert_to_buf(buf, &l, x)) |
| 1048 | return 0; |
| 1049 | } |
| 1050 | |
| 1051 | l-= (3 + DTLS1_HM_HEADER_LENGTH); |
| 1052 | |
| 1053 | p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]); |
| 1054 | l2n3(l,p); |
| 1055 | l+=3; |
| 1056 | p=(unsigned char *)&(buf->data[0]); |
| 1057 | p = dtls1_set_message_header(s, p, SSL3_MT_CERTIFICATE, l, 0, l); |
| 1058 | |
| 1059 | l+=DTLS1_HM_HEADER_LENGTH; |
| 1060 | return(l); |
| 1061 | } |
| 1062 | |
| 1063 | int dtls1_read_failed(SSL *s, int code) |
| 1064 | { |
| 1065 | if ( code > 0) |
| 1066 | { |
| 1067 | fprintf( stderr, "invalid state reached %s:%d", __FILE__, __LINE__); |
| 1068 | return 1; |
| 1069 | } |
| 1070 | |
| 1071 | if (!dtls1_is_timer_expired(s)) |
| 1072 | { |
| 1073 | /* not a timeout, none of our business, |
| 1074 | let higher layers handle this. in fact it's probably an error */ |
| 1075 | return code; |
| 1076 | } |
| 1077 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 1078 | if ( ! SSL_in_init(s)) /* done, no need to send a retransmit */ |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 1079 | { |
| 1080 | BIO_set_flags(SSL_get_rbio(s), BIO_FLAGS_READ); |
| 1081 | return code; |
| 1082 | } |
| 1083 | |
| 1084 | #if 0 /* for now, each alert contains only one record number */ |
| 1085 | item = pqueue_peek(state->rcvd_records); |
| 1086 | if ( item ) |
| 1087 | { |
| 1088 | /* send an alert immediately for all the missing records */ |
| 1089 | } |
| 1090 | else |
| 1091 | #endif |
| 1092 | |
| 1093 | #if 0 /* no more alert sending, just retransmit the last set of messages */ |
| 1094 | if ( state->timeout.read_timeouts >= DTLS1_TMO_READ_COUNT) |
| 1095 | ssl3_send_alert(s,SSL3_AL_WARNING, |
| 1096 | DTLS1_AD_MISSING_HANDSHAKE_MESSAGE); |
| 1097 | #endif |
| 1098 | |
| 1099 | return dtls1_handle_timeout(s); |
| 1100 | } |
| 1101 | |
| 1102 | int |
| 1103 | dtls1_get_queue_priority(unsigned short seq, int is_ccs) |
| 1104 | { |
| 1105 | /* The index of the retransmission queue actually is the message sequence number, |
| 1106 | * since the queue only contains messages of a single handshake. However, the |
| 1107 | * ChangeCipherSpec has no message sequence number and so using only the sequence |
| 1108 | * will result in the CCS and Finished having the same index. To prevent this, |
| 1109 | * the sequence number is multiplied by 2. In case of a CCS 1 is subtracted. |
| 1110 | * This does not only differ CSS and Finished, it also maintains the order of the |
| 1111 | * index (important for priority queues) and fits in the unsigned short variable. |
| 1112 | */ |
| 1113 | return seq * 2 - is_ccs; |
| 1114 | } |
| 1115 | |
| 1116 | int |
| 1117 | dtls1_retransmit_buffered_messages(SSL *s) |
| 1118 | { |
| 1119 | pqueue sent = s->d1->sent_messages; |
| 1120 | piterator iter; |
| 1121 | pitem *item; |
| 1122 | hm_fragment *frag; |
| 1123 | int found = 0; |
| 1124 | |
| 1125 | iter = pqueue_iterator(sent); |
| 1126 | |
| 1127 | for ( item = pqueue_next(&iter); item != NULL; item = pqueue_next(&iter)) |
| 1128 | { |
| 1129 | frag = (hm_fragment *)item->data; |
| 1130 | if ( dtls1_retransmit_message(s, |
| 1131 | (unsigned short)dtls1_get_queue_priority(frag->msg_header.seq, frag->msg_header.is_ccs), |
| 1132 | 0, &found) <= 0 && found) |
| 1133 | { |
| 1134 | fprintf(stderr, "dtls1_retransmit_message() failed\n"); |
| 1135 | return -1; |
| 1136 | } |
| 1137 | } |
| 1138 | |
| 1139 | return 1; |
| 1140 | } |
| 1141 | |
| 1142 | int |
| 1143 | dtls1_buffer_message(SSL *s, int is_ccs) |
| 1144 | { |
| 1145 | pitem *item; |
| 1146 | hm_fragment *frag; |
| 1147 | unsigned char seq64be[8]; |
| 1148 | |
| 1149 | /* this function is called immediately after a message has |
| 1150 | * been serialized */ |
| 1151 | OPENSSL_assert(s->init_off == 0); |
| 1152 | |
| 1153 | frag = dtls1_hm_fragment_new(s->init_num, 0); |
| 1154 | |
| 1155 | memcpy(frag->fragment, s->init_buf->data, s->init_num); |
| 1156 | |
| 1157 | if ( is_ccs) |
| 1158 | { |
| 1159 | OPENSSL_assert(s->d1->w_msg_hdr.msg_len + |
| 1160 | ((s->version==DTLS1_VERSION)?DTLS1_CCS_HEADER_LENGTH:3) == (unsigned int)s->init_num); |
| 1161 | } |
| 1162 | else |
| 1163 | { |
| 1164 | OPENSSL_assert(s->d1->w_msg_hdr.msg_len + |
| 1165 | DTLS1_HM_HEADER_LENGTH == (unsigned int)s->init_num); |
| 1166 | } |
| 1167 | |
| 1168 | frag->msg_header.msg_len = s->d1->w_msg_hdr.msg_len; |
| 1169 | frag->msg_header.seq = s->d1->w_msg_hdr.seq; |
| 1170 | frag->msg_header.type = s->d1->w_msg_hdr.type; |
| 1171 | frag->msg_header.frag_off = 0; |
| 1172 | frag->msg_header.frag_len = s->d1->w_msg_hdr.msg_len; |
| 1173 | frag->msg_header.is_ccs = is_ccs; |
| 1174 | |
| 1175 | /* save current state*/ |
| 1176 | frag->msg_header.saved_retransmit_state.enc_write_ctx = s->enc_write_ctx; |
| 1177 | frag->msg_header.saved_retransmit_state.write_hash = s->write_hash; |
| 1178 | frag->msg_header.saved_retransmit_state.compress = s->compress; |
| 1179 | frag->msg_header.saved_retransmit_state.session = s->session; |
| 1180 | frag->msg_header.saved_retransmit_state.epoch = s->d1->w_epoch; |
| 1181 | |
| 1182 | memset(seq64be,0,sizeof(seq64be)); |
| 1183 | seq64be[6] = (unsigned char)(dtls1_get_queue_priority(frag->msg_header.seq, |
| 1184 | frag->msg_header.is_ccs)>>8); |
| 1185 | seq64be[7] = (unsigned char)(dtls1_get_queue_priority(frag->msg_header.seq, |
| 1186 | frag->msg_header.is_ccs)); |
| 1187 | |
| 1188 | item = pitem_new(seq64be, frag); |
| 1189 | if ( item == NULL) |
| 1190 | { |
| 1191 | dtls1_hm_fragment_free(frag); |
| 1192 | return 0; |
| 1193 | } |
| 1194 | |
| 1195 | #if 0 |
| 1196 | fprintf( stderr, "buffered messge: \ttype = %xx\n", msg_buf->type); |
| 1197 | fprintf( stderr, "\t\t\t\t\tlen = %d\n", msg_buf->len); |
| 1198 | fprintf( stderr, "\t\t\t\t\tseq_num = %d\n", msg_buf->seq_num); |
| 1199 | #endif |
| 1200 | |
| 1201 | pqueue_insert(s->d1->sent_messages, item); |
| 1202 | return 1; |
| 1203 | } |
| 1204 | |
| 1205 | int |
| 1206 | dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off, |
| 1207 | int *found) |
| 1208 | { |
| 1209 | int ret; |
| 1210 | /* XDTLS: for now assuming that read/writes are blocking */ |
| 1211 | pitem *item; |
| 1212 | hm_fragment *frag ; |
| 1213 | unsigned long header_length; |
| 1214 | unsigned char seq64be[8]; |
| 1215 | struct dtls1_retransmit_state saved_state; |
| 1216 | unsigned char save_write_sequence[8]; |
| 1217 | |
| 1218 | /* |
| 1219 | OPENSSL_assert(s->init_num == 0); |
| 1220 | OPENSSL_assert(s->init_off == 0); |
| 1221 | */ |
| 1222 | |
| 1223 | /* XDTLS: the requested message ought to be found, otherwise error */ |
| 1224 | memset(seq64be,0,sizeof(seq64be)); |
| 1225 | seq64be[6] = (unsigned char)(seq>>8); |
| 1226 | seq64be[7] = (unsigned char)seq; |
| 1227 | |
| 1228 | item = pqueue_find(s->d1->sent_messages, seq64be); |
| 1229 | if ( item == NULL) |
| 1230 | { |
| 1231 | fprintf(stderr, "retransmit: message %d non-existant\n", seq); |
| 1232 | *found = 0; |
| 1233 | return 0; |
| 1234 | } |
| 1235 | |
| 1236 | *found = 1; |
| 1237 | frag = (hm_fragment *)item->data; |
| 1238 | |
| 1239 | if ( frag->msg_header.is_ccs) |
| 1240 | header_length = DTLS1_CCS_HEADER_LENGTH; |
| 1241 | else |
| 1242 | header_length = DTLS1_HM_HEADER_LENGTH; |
| 1243 | |
| 1244 | memcpy(s->init_buf->data, frag->fragment, |
| 1245 | frag->msg_header.msg_len + header_length); |
| 1246 | s->init_num = frag->msg_header.msg_len + header_length; |
| 1247 | |
| 1248 | dtls1_set_message_header_int(s, frag->msg_header.type, |
| 1249 | frag->msg_header.msg_len, frag->msg_header.seq, 0, |
| 1250 | frag->msg_header.frag_len); |
| 1251 | |
| 1252 | /* save current state */ |
| 1253 | saved_state.enc_write_ctx = s->enc_write_ctx; |
| 1254 | saved_state.write_hash = s->write_hash; |
| 1255 | saved_state.compress = s->compress; |
| 1256 | saved_state.session = s->session; |
| 1257 | saved_state.epoch = s->d1->w_epoch; |
| 1258 | saved_state.epoch = s->d1->w_epoch; |
| 1259 | |
| 1260 | s->d1->retransmitting = 1; |
| 1261 | |
| 1262 | /* restore state in which the message was originally sent */ |
| 1263 | s->enc_write_ctx = frag->msg_header.saved_retransmit_state.enc_write_ctx; |
| 1264 | s->write_hash = frag->msg_header.saved_retransmit_state.write_hash; |
| 1265 | s->compress = frag->msg_header.saved_retransmit_state.compress; |
| 1266 | s->session = frag->msg_header.saved_retransmit_state.session; |
| 1267 | s->d1->w_epoch = frag->msg_header.saved_retransmit_state.epoch; |
| 1268 | |
| 1269 | if (frag->msg_header.saved_retransmit_state.epoch == saved_state.epoch - 1) |
| 1270 | { |
| 1271 | memcpy(save_write_sequence, s->s3->write_sequence, sizeof(s->s3->write_sequence)); |
| 1272 | memcpy(s->s3->write_sequence, s->d1->last_write_sequence, sizeof(s->s3->write_sequence)); |
| 1273 | } |
| 1274 | |
| 1275 | ret = dtls1_do_write(s, frag->msg_header.is_ccs ? |
| 1276 | SSL3_RT_CHANGE_CIPHER_SPEC : SSL3_RT_HANDSHAKE); |
| 1277 | |
| 1278 | /* restore current state */ |
| 1279 | s->enc_write_ctx = saved_state.enc_write_ctx; |
| 1280 | s->write_hash = saved_state.write_hash; |
| 1281 | s->compress = saved_state.compress; |
| 1282 | s->session = saved_state.session; |
| 1283 | s->d1->w_epoch = saved_state.epoch; |
| 1284 | |
| 1285 | if (frag->msg_header.saved_retransmit_state.epoch == saved_state.epoch - 1) |
| 1286 | { |
| 1287 | memcpy(s->d1->last_write_sequence, s->s3->write_sequence, sizeof(s->s3->write_sequence)); |
| 1288 | memcpy(s->s3->write_sequence, save_write_sequence, sizeof(s->s3->write_sequence)); |
| 1289 | } |
| 1290 | |
| 1291 | s->d1->retransmitting = 0; |
| 1292 | |
| 1293 | (void)BIO_flush(SSL_get_wbio(s)); |
| 1294 | return ret; |
| 1295 | } |
| 1296 | |
| 1297 | /* call this function when the buffered messages are no longer needed */ |
| 1298 | void |
| 1299 | dtls1_clear_record_buffer(SSL *s) |
| 1300 | { |
| 1301 | pitem *item; |
| 1302 | |
| 1303 | for(item = pqueue_pop(s->d1->sent_messages); |
| 1304 | item != NULL; item = pqueue_pop(s->d1->sent_messages)) |
| 1305 | { |
| 1306 | dtls1_hm_fragment_free((hm_fragment *)item->data); |
| 1307 | pitem_free(item); |
| 1308 | } |
| 1309 | } |
| 1310 | |
| 1311 | |
| 1312 | unsigned char * |
| 1313 | dtls1_set_message_header(SSL *s, unsigned char *p, unsigned char mt, |
| 1314 | unsigned long len, unsigned long frag_off, unsigned long frag_len) |
| 1315 | { |
| 1316 | /* Don't change sequence numbers while listening */ |
| 1317 | if (frag_off == 0 && !s->d1->listen) |
| 1318 | { |
| 1319 | s->d1->handshake_write_seq = s->d1->next_handshake_write_seq; |
| 1320 | s->d1->next_handshake_write_seq++; |
| 1321 | } |
| 1322 | |
| 1323 | dtls1_set_message_header_int(s, mt, len, s->d1->handshake_write_seq, |
| 1324 | frag_off, frag_len); |
| 1325 | |
| 1326 | return p += DTLS1_HM_HEADER_LENGTH; |
| 1327 | } |
| 1328 | |
| 1329 | |
| 1330 | /* don't actually do the writing, wait till the MTU has been retrieved */ |
| 1331 | static void |
| 1332 | dtls1_set_message_header_int(SSL *s, unsigned char mt, |
| 1333 | unsigned long len, unsigned short seq_num, unsigned long frag_off, |
| 1334 | unsigned long frag_len) |
| 1335 | { |
| 1336 | struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; |
| 1337 | |
| 1338 | msg_hdr->type = mt; |
| 1339 | msg_hdr->msg_len = len; |
| 1340 | msg_hdr->seq = seq_num; |
| 1341 | msg_hdr->frag_off = frag_off; |
| 1342 | msg_hdr->frag_len = frag_len; |
| 1343 | } |
| 1344 | |
| 1345 | static void |
| 1346 | dtls1_fix_message_header(SSL *s, unsigned long frag_off, |
| 1347 | unsigned long frag_len) |
| 1348 | { |
| 1349 | struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; |
| 1350 | |
| 1351 | msg_hdr->frag_off = frag_off; |
| 1352 | msg_hdr->frag_len = frag_len; |
| 1353 | } |
| 1354 | |
| 1355 | static unsigned char * |
| 1356 | dtls1_write_message_header(SSL *s, unsigned char *p) |
| 1357 | { |
| 1358 | struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; |
| 1359 | |
| 1360 | *p++ = msg_hdr->type; |
| 1361 | l2n3(msg_hdr->msg_len, p); |
| 1362 | |
| 1363 | s2n(msg_hdr->seq, p); |
| 1364 | l2n3(msg_hdr->frag_off, p); |
| 1365 | l2n3(msg_hdr->frag_len, p); |
| 1366 | |
| 1367 | return p; |
| 1368 | } |
| 1369 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 1370 | static unsigned int |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 1371 | dtls1_min_mtu(void) |
| 1372 | { |
| 1373 | return (g_probable_mtu[(sizeof(g_probable_mtu) / |
| 1374 | sizeof(g_probable_mtu[0])) - 1]); |
| 1375 | } |
| 1376 | |
| 1377 | static unsigned int |
| 1378 | dtls1_guess_mtu(unsigned int curr_mtu) |
| 1379 | { |
| 1380 | unsigned int i; |
| 1381 | |
| 1382 | if ( curr_mtu == 0 ) |
| 1383 | return g_probable_mtu[0] ; |
| 1384 | |
| 1385 | for ( i = 0; i < sizeof(g_probable_mtu)/sizeof(g_probable_mtu[0]); i++) |
| 1386 | if ( curr_mtu > g_probable_mtu[i]) |
| 1387 | return g_probable_mtu[i]; |
| 1388 | |
| 1389 | return curr_mtu; |
| 1390 | } |
| 1391 | |
| 1392 | void |
| 1393 | dtls1_get_message_header(unsigned char *data, struct hm_header_st *msg_hdr) |
| 1394 | { |
| 1395 | memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); |
| 1396 | msg_hdr->type = *(data++); |
| 1397 | n2l3(data, msg_hdr->msg_len); |
| 1398 | |
| 1399 | n2s(data, msg_hdr->seq); |
| 1400 | n2l3(data, msg_hdr->frag_off); |
| 1401 | n2l3(data, msg_hdr->frag_len); |
| 1402 | } |
| 1403 | |
| 1404 | void |
| 1405 | dtls1_get_ccs_header(unsigned char *data, struct ccs_header_st *ccs_hdr) |
| 1406 | { |
| 1407 | memset(ccs_hdr, 0x00, sizeof(struct ccs_header_st)); |
| 1408 | |
| 1409 | ccs_hdr->type = *(data++); |
| 1410 | } |