Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 1 | /* crypto/evp/bio_ok.c */ |
| 2 | /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * This package is an SSL implementation written |
| 6 | * by Eric Young (eay@cryptsoft.com). |
| 7 | * The implementation was written so as to conform with Netscapes SSL. |
| 8 | * |
| 9 | * This library is free for commercial and non-commercial use as long as |
| 10 | * the following conditions are aheared to. The following conditions |
| 11 | * apply to all code found in this distribution, be it the RC4, RSA, |
| 12 | * lhash, DES, etc., code; not just the SSL code. The SSL documentation |
| 13 | * included with this distribution is covered by the same copyright terms |
| 14 | * except that the holder is Tim Hudson (tjh@cryptsoft.com). |
| 15 | * |
| 16 | * Copyright remains Eric Young's, and as such any Copyright notices in |
| 17 | * the code are not to be removed. |
| 18 | * If this package is used in a product, Eric Young should be given attribution |
| 19 | * as the author of the parts of the library used. |
| 20 | * This can be in the form of a textual message at program startup or |
| 21 | * in documentation (online or textual) provided with the package. |
| 22 | * |
| 23 | * Redistribution and use in source and binary forms, with or without |
| 24 | * modification, are permitted provided that the following conditions |
| 25 | * are met: |
| 26 | * 1. Redistributions of source code must retain the copyright |
| 27 | * notice, this list of conditions and the following disclaimer. |
| 28 | * 2. Redistributions in binary form must reproduce the above copyright |
| 29 | * notice, this list of conditions and the following disclaimer in the |
| 30 | * documentation and/or other materials provided with the distribution. |
| 31 | * 3. All advertising materials mentioning features or use of this software |
| 32 | * must display the following acknowledgement: |
| 33 | * "This product includes cryptographic software written by |
| 34 | * Eric Young (eay@cryptsoft.com)" |
| 35 | * The word 'cryptographic' can be left out if the rouines from the library |
| 36 | * being used are not cryptographic related :-). |
| 37 | * 4. If you include any Windows specific code (or a derivative thereof) from |
| 38 | * the apps directory (application code) you must include an acknowledgement: |
| 39 | * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" |
| 40 | * |
| 41 | * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND |
| 42 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 43 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 44 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| 45 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 46 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 47 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 48 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 49 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 50 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 51 | * SUCH DAMAGE. |
| 52 | * |
| 53 | * The licence and distribution terms for any publically available version or |
| 54 | * derivative of this code cannot be changed. i.e. this code cannot simply be |
| 55 | * copied and put under another distribution licence |
| 56 | * [including the GNU Public Licence.] |
| 57 | */ |
| 58 | |
| 59 | /* |
| 60 | From: Arne Ansper <arne@cyber.ee> |
| 61 | |
| 62 | Why BIO_f_reliable? |
| 63 | |
| 64 | I wrote function which took BIO* as argument, read data from it |
| 65 | and processed it. Then I wanted to store the input file in |
| 66 | encrypted form. OK I pushed BIO_f_cipher to the BIO stack |
| 67 | and everything was OK. BUT if user types wrong password |
| 68 | BIO_f_cipher outputs only garbage and my function crashes. Yes |
| 69 | I can and I should fix my function, but BIO_f_cipher is |
| 70 | easy way to add encryption support to many existing applications |
| 71 | and it's hard to debug and fix them all. |
| 72 | |
| 73 | So I wanted another BIO which would catch the incorrect passwords and |
| 74 | file damages which cause garbage on BIO_f_cipher's output. |
| 75 | |
| 76 | The easy way is to push the BIO_f_md and save the checksum at |
| 77 | the end of the file. However there are several problems with this |
| 78 | approach: |
| 79 | |
| 80 | 1) you must somehow separate checksum from actual data. |
| 81 | 2) you need lot's of memory when reading the file, because you |
| 82 | must read to the end of the file and verify the checksum before |
| 83 | letting the application to read the data. |
| 84 | |
| 85 | BIO_f_reliable tries to solve both problems, so that you can |
| 86 | read and write arbitrary long streams using only fixed amount |
| 87 | of memory. |
| 88 | |
| 89 | BIO_f_reliable splits data stream into blocks. Each block is prefixed |
| 90 | with it's length and suffixed with it's digest. So you need only |
| 91 | several Kbytes of memory to buffer single block before verifying |
| 92 | it's digest. |
| 93 | |
| 94 | BIO_f_reliable goes further and adds several important capabilities: |
| 95 | |
| 96 | 1) the digest of the block is computed over the whole stream |
| 97 | -- so nobody can rearrange the blocks or remove or replace them. |
| 98 | |
| 99 | 2) to detect invalid passwords right at the start BIO_f_reliable |
| 100 | adds special prefix to the stream. In order to avoid known plain-text |
| 101 | attacks this prefix is generated as follows: |
| 102 | |
| 103 | *) digest is initialized with random seed instead of |
| 104 | standardized one. |
| 105 | *) same seed is written to output |
| 106 | *) well-known text is then hashed and the output |
| 107 | of the digest is also written to output. |
| 108 | |
| 109 | reader can now read the seed from stream, hash the same string |
| 110 | and then compare the digest output. |
| 111 | |
| 112 | Bad things: BIO_f_reliable knows what's going on in EVP_Digest. I |
| 113 | initially wrote and tested this code on x86 machine and wrote the |
| 114 | digests out in machine-dependent order :( There are people using |
| 115 | this code and I cannot change this easily without making existing |
| 116 | data files unreadable. |
| 117 | |
| 118 | */ |
| 119 | |
| 120 | #include <stdio.h> |
| 121 | #include <errno.h> |
| 122 | #include <assert.h> |
| 123 | #include "cryptlib.h" |
| 124 | #include <openssl/buffer.h> |
| 125 | #include <openssl/bio.h> |
| 126 | #include <openssl/evp.h> |
| 127 | #include <openssl/rand.h> |
| 128 | |
| 129 | static int ok_write(BIO *h, const char *buf, int num); |
| 130 | static int ok_read(BIO *h, char *buf, int size); |
| 131 | static long ok_ctrl(BIO *h, int cmd, long arg1, void *arg2); |
| 132 | static int ok_new(BIO *h); |
| 133 | static int ok_free(BIO *data); |
| 134 | static long ok_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp); |
| 135 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 136 | static void sig_out(BIO* b); |
| 137 | static void sig_in(BIO* b); |
| 138 | static void block_out(BIO* b); |
| 139 | static void block_in(BIO* b); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 140 | #define OK_BLOCK_SIZE (1024*4) |
| 141 | #define OK_BLOCK_BLOCK 4 |
| 142 | #define IOBS (OK_BLOCK_SIZE+ OK_BLOCK_BLOCK+ 3*EVP_MAX_MD_SIZE) |
| 143 | #define WELLKNOWN "The quick brown fox jumped over the lazy dog's back." |
| 144 | |
| 145 | typedef struct ok_struct |
| 146 | { |
| 147 | size_t buf_len; |
| 148 | size_t buf_off; |
| 149 | size_t buf_len_save; |
| 150 | size_t buf_off_save; |
| 151 | int cont; /* <= 0 when finished */ |
| 152 | int finished; |
| 153 | EVP_MD_CTX md; |
| 154 | int blockout; /* output block is ready */ |
| 155 | int sigio; /* must process signature */ |
| 156 | unsigned char buf[IOBS]; |
| 157 | } BIO_OK_CTX; |
| 158 | |
| 159 | static BIO_METHOD methods_ok= |
| 160 | { |
| 161 | BIO_TYPE_CIPHER,"reliable", |
| 162 | ok_write, |
| 163 | ok_read, |
| 164 | NULL, /* ok_puts, */ |
| 165 | NULL, /* ok_gets, */ |
| 166 | ok_ctrl, |
| 167 | ok_new, |
| 168 | ok_free, |
| 169 | ok_callback_ctrl, |
| 170 | }; |
| 171 | |
| 172 | BIO_METHOD *BIO_f_reliable(void) |
| 173 | { |
| 174 | return(&methods_ok); |
| 175 | } |
| 176 | |
| 177 | static int ok_new(BIO *bi) |
| 178 | { |
| 179 | BIO_OK_CTX *ctx; |
| 180 | |
| 181 | ctx=(BIO_OK_CTX *)OPENSSL_malloc(sizeof(BIO_OK_CTX)); |
| 182 | if (ctx == NULL) return(0); |
| 183 | |
| 184 | ctx->buf_len=0; |
| 185 | ctx->buf_off=0; |
| 186 | ctx->buf_len_save=0; |
| 187 | ctx->buf_off_save=0; |
| 188 | ctx->cont=1; |
| 189 | ctx->finished=0; |
| 190 | ctx->blockout= 0; |
| 191 | ctx->sigio=1; |
| 192 | |
| 193 | EVP_MD_CTX_init(&ctx->md); |
| 194 | |
| 195 | bi->init=0; |
| 196 | bi->ptr=(char *)ctx; |
| 197 | bi->flags=0; |
| 198 | return(1); |
| 199 | } |
| 200 | |
| 201 | static int ok_free(BIO *a) |
| 202 | { |
| 203 | if (a == NULL) return(0); |
| 204 | EVP_MD_CTX_cleanup(&((BIO_OK_CTX *)a->ptr)->md); |
| 205 | OPENSSL_cleanse(a->ptr,sizeof(BIO_OK_CTX)); |
| 206 | OPENSSL_free(a->ptr); |
| 207 | a->ptr=NULL; |
| 208 | a->init=0; |
| 209 | a->flags=0; |
| 210 | return(1); |
| 211 | } |
| 212 | |
| 213 | static int ok_read(BIO *b, char *out, int outl) |
| 214 | { |
| 215 | int ret=0,i,n; |
| 216 | BIO_OK_CTX *ctx; |
| 217 | |
| 218 | if (out == NULL) return(0); |
| 219 | ctx=(BIO_OK_CTX *)b->ptr; |
| 220 | |
| 221 | if ((ctx == NULL) || (b->next_bio == NULL) || (b->init == 0)) return(0); |
| 222 | |
| 223 | while(outl > 0) |
| 224 | { |
| 225 | |
| 226 | /* copy clean bytes to output buffer */ |
| 227 | if (ctx->blockout) |
| 228 | { |
| 229 | i=ctx->buf_len-ctx->buf_off; |
| 230 | if (i > outl) i=outl; |
| 231 | memcpy(out,&(ctx->buf[ctx->buf_off]),i); |
| 232 | ret+=i; |
| 233 | out+=i; |
| 234 | outl-=i; |
| 235 | ctx->buf_off+=i; |
| 236 | |
| 237 | /* all clean bytes are out */ |
| 238 | if (ctx->buf_len == ctx->buf_off) |
| 239 | { |
| 240 | ctx->buf_off=0; |
| 241 | |
| 242 | /* copy start of the next block into proper place */ |
| 243 | if(ctx->buf_len_save- ctx->buf_off_save > 0) |
| 244 | { |
| 245 | ctx->buf_len= ctx->buf_len_save- ctx->buf_off_save; |
| 246 | memmove(ctx->buf, &(ctx->buf[ctx->buf_off_save]), |
| 247 | ctx->buf_len); |
| 248 | } |
| 249 | else |
| 250 | { |
| 251 | ctx->buf_len=0; |
| 252 | } |
| 253 | ctx->blockout= 0; |
| 254 | } |
| 255 | } |
| 256 | |
| 257 | /* output buffer full -- cancel */ |
| 258 | if (outl == 0) break; |
| 259 | |
| 260 | /* no clean bytes in buffer -- fill it */ |
| 261 | n=IOBS- ctx->buf_len; |
| 262 | i=BIO_read(b->next_bio,&(ctx->buf[ctx->buf_len]),n); |
| 263 | |
| 264 | if (i <= 0) break; /* nothing new */ |
| 265 | |
| 266 | ctx->buf_len+= i; |
| 267 | |
| 268 | /* no signature yet -- check if we got one */ |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 269 | if (ctx->sigio == 1) sig_in(b); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 270 | |
| 271 | /* signature ok -- check if we got block */ |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 272 | if (ctx->sigio == 0) block_in(b); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 273 | |
| 274 | /* invalid block -- cancel */ |
| 275 | if (ctx->cont <= 0) break; |
| 276 | |
| 277 | } |
| 278 | |
| 279 | BIO_clear_retry_flags(b); |
| 280 | BIO_copy_next_retry(b); |
| 281 | return(ret); |
| 282 | } |
| 283 | |
| 284 | static int ok_write(BIO *b, const char *in, int inl) |
| 285 | { |
| 286 | int ret=0,n,i; |
| 287 | BIO_OK_CTX *ctx; |
| 288 | |
| 289 | if (inl <= 0) return inl; |
| 290 | |
| 291 | ctx=(BIO_OK_CTX *)b->ptr; |
| 292 | ret=inl; |
| 293 | |
| 294 | if ((ctx == NULL) || (b->next_bio == NULL) || (b->init == 0)) return(0); |
| 295 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 296 | if(ctx->sigio) sig_out(b); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 297 | |
| 298 | do{ |
| 299 | BIO_clear_retry_flags(b); |
| 300 | n=ctx->buf_len-ctx->buf_off; |
| 301 | while (ctx->blockout && n > 0) |
| 302 | { |
| 303 | i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n); |
| 304 | if (i <= 0) |
| 305 | { |
| 306 | BIO_copy_next_retry(b); |
| 307 | if(!BIO_should_retry(b)) |
| 308 | ctx->cont= 0; |
| 309 | return(i); |
| 310 | } |
| 311 | ctx->buf_off+=i; |
| 312 | n-=i; |
| 313 | } |
| 314 | |
| 315 | /* at this point all pending data has been written */ |
| 316 | ctx->blockout= 0; |
| 317 | if (ctx->buf_len == ctx->buf_off) |
| 318 | { |
| 319 | ctx->buf_len=OK_BLOCK_BLOCK; |
| 320 | ctx->buf_off=0; |
| 321 | } |
| 322 | |
| 323 | if ((in == NULL) || (inl <= 0)) return(0); |
| 324 | |
| 325 | n= (inl+ ctx->buf_len > OK_BLOCK_SIZE+ OK_BLOCK_BLOCK) ? |
| 326 | (int)(OK_BLOCK_SIZE+OK_BLOCK_BLOCK-ctx->buf_len) : inl; |
| 327 | |
| 328 | memcpy((unsigned char *)(&(ctx->buf[ctx->buf_len])),(unsigned char *)in,n); |
| 329 | ctx->buf_len+= n; |
| 330 | inl-=n; |
| 331 | in+=n; |
| 332 | |
| 333 | if(ctx->buf_len >= OK_BLOCK_SIZE+ OK_BLOCK_BLOCK) |
| 334 | { |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 335 | block_out(b); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 336 | } |
| 337 | }while(inl > 0); |
| 338 | |
| 339 | BIO_clear_retry_flags(b); |
| 340 | BIO_copy_next_retry(b); |
| 341 | return(ret); |
| 342 | } |
| 343 | |
| 344 | static long ok_ctrl(BIO *b, int cmd, long num, void *ptr) |
| 345 | { |
| 346 | BIO_OK_CTX *ctx; |
| 347 | EVP_MD *md; |
| 348 | const EVP_MD **ppmd; |
| 349 | long ret=1; |
| 350 | int i; |
| 351 | |
| 352 | ctx=b->ptr; |
| 353 | |
| 354 | switch (cmd) |
| 355 | { |
| 356 | case BIO_CTRL_RESET: |
| 357 | ctx->buf_len=0; |
| 358 | ctx->buf_off=0; |
| 359 | ctx->buf_len_save=0; |
| 360 | ctx->buf_off_save=0; |
| 361 | ctx->cont=1; |
| 362 | ctx->finished=0; |
| 363 | ctx->blockout= 0; |
| 364 | ctx->sigio=1; |
| 365 | ret=BIO_ctrl(b->next_bio,cmd,num,ptr); |
| 366 | break; |
| 367 | case BIO_CTRL_EOF: /* More to read */ |
| 368 | if (ctx->cont <= 0) |
| 369 | ret=1; |
| 370 | else |
| 371 | ret=BIO_ctrl(b->next_bio,cmd,num,ptr); |
| 372 | break; |
| 373 | case BIO_CTRL_PENDING: /* More to read in buffer */ |
| 374 | case BIO_CTRL_WPENDING: /* More to read in buffer */ |
| 375 | ret=ctx->blockout ? ctx->buf_len-ctx->buf_off : 0; |
| 376 | if (ret <= 0) |
| 377 | ret=BIO_ctrl(b->next_bio,cmd,num,ptr); |
| 378 | break; |
| 379 | case BIO_CTRL_FLUSH: |
| 380 | /* do a final write */ |
| 381 | if(ctx->blockout == 0) |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 382 | block_out(b); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 383 | |
| 384 | while (ctx->blockout) |
| 385 | { |
| 386 | i=ok_write(b,NULL,0); |
| 387 | if (i < 0) |
| 388 | { |
| 389 | ret=i; |
| 390 | break; |
| 391 | } |
| 392 | } |
| 393 | |
| 394 | ctx->finished=1; |
| 395 | ctx->buf_off=ctx->buf_len=0; |
| 396 | ctx->cont=(int)ret; |
| 397 | |
| 398 | /* Finally flush the underlying BIO */ |
| 399 | ret=BIO_ctrl(b->next_bio,cmd,num,ptr); |
| 400 | break; |
| 401 | case BIO_C_DO_STATE_MACHINE: |
| 402 | BIO_clear_retry_flags(b); |
| 403 | ret=BIO_ctrl(b->next_bio,cmd,num,ptr); |
| 404 | BIO_copy_next_retry(b); |
| 405 | break; |
| 406 | case BIO_CTRL_INFO: |
| 407 | ret=(long)ctx->cont; |
| 408 | break; |
| 409 | case BIO_C_SET_MD: |
| 410 | md=ptr; |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 411 | EVP_DigestInit_ex(&ctx->md, md, NULL); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 412 | b->init=1; |
| 413 | break; |
| 414 | case BIO_C_GET_MD: |
| 415 | if (b->init) |
| 416 | { |
| 417 | ppmd=ptr; |
| 418 | *ppmd=ctx->md.digest; |
| 419 | } |
| 420 | else |
| 421 | ret=0; |
| 422 | break; |
| 423 | default: |
| 424 | ret=BIO_ctrl(b->next_bio,cmd,num,ptr); |
| 425 | break; |
| 426 | } |
| 427 | return(ret); |
| 428 | } |
| 429 | |
| 430 | static long ok_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp) |
| 431 | { |
| 432 | long ret=1; |
| 433 | |
| 434 | if (b->next_bio == NULL) return(0); |
| 435 | switch (cmd) |
| 436 | { |
| 437 | default: |
| 438 | ret=BIO_callback_ctrl(b->next_bio,cmd,fp); |
| 439 | break; |
| 440 | } |
| 441 | return(ret); |
| 442 | } |
| 443 | |
| 444 | static void longswap(void *_ptr, size_t len) |
| 445 | { const union { long one; char little; } is_endian = {1}; |
| 446 | |
| 447 | if (is_endian.little) { |
| 448 | size_t i; |
| 449 | unsigned char *p=_ptr,c; |
| 450 | |
| 451 | for(i= 0;i < len;i+= 4) { |
| 452 | c=p[0],p[0]=p[3],p[3]=c; |
| 453 | c=p[1],p[1]=p[2],p[2]=c; |
| 454 | } |
| 455 | } |
| 456 | } |
| 457 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 458 | static void sig_out(BIO* b) |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 459 | { |
| 460 | BIO_OK_CTX *ctx; |
| 461 | EVP_MD_CTX *md; |
| 462 | |
| 463 | ctx=b->ptr; |
| 464 | md=&ctx->md; |
| 465 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 466 | if(ctx->buf_len+ 2* md->digest->md_size > OK_BLOCK_SIZE) return; |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 467 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 468 | EVP_DigestInit_ex(md, md->digest, NULL); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 469 | /* FIXME: there's absolutely no guarantee this makes any sense at all, |
| 470 | * particularly now EVP_MD_CTX has been restructured. |
| 471 | */ |
| 472 | RAND_pseudo_bytes(md->md_data, md->digest->md_size); |
| 473 | memcpy(&(ctx->buf[ctx->buf_len]), md->md_data, md->digest->md_size); |
| 474 | longswap(&(ctx->buf[ctx->buf_len]), md->digest->md_size); |
| 475 | ctx->buf_len+= md->digest->md_size; |
| 476 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 477 | EVP_DigestUpdate(md, WELLKNOWN, strlen(WELLKNOWN)); |
| 478 | EVP_DigestFinal_ex(md, &(ctx->buf[ctx->buf_len]), NULL); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 479 | ctx->buf_len+= md->digest->md_size; |
| 480 | ctx->blockout= 1; |
| 481 | ctx->sigio= 0; |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 482 | } |
| 483 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 484 | static void sig_in(BIO* b) |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 485 | { |
| 486 | BIO_OK_CTX *ctx; |
| 487 | EVP_MD_CTX *md; |
| 488 | unsigned char tmp[EVP_MAX_MD_SIZE]; |
| 489 | int ret= 0; |
| 490 | |
| 491 | ctx=b->ptr; |
| 492 | md=&ctx->md; |
| 493 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 494 | if((int)(ctx->buf_len-ctx->buf_off) < 2*md->digest->md_size) return; |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 495 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 496 | EVP_DigestInit_ex(md, md->digest, NULL); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 497 | memcpy(md->md_data, &(ctx->buf[ctx->buf_off]), md->digest->md_size); |
| 498 | longswap(md->md_data, md->digest->md_size); |
| 499 | ctx->buf_off+= md->digest->md_size; |
| 500 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 501 | EVP_DigestUpdate(md, WELLKNOWN, strlen(WELLKNOWN)); |
| 502 | EVP_DigestFinal_ex(md, tmp, NULL); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 503 | ret= memcmp(&(ctx->buf[ctx->buf_off]), tmp, md->digest->md_size) == 0; |
| 504 | ctx->buf_off+= md->digest->md_size; |
| 505 | if(ret == 1) |
| 506 | { |
| 507 | ctx->sigio= 0; |
| 508 | if(ctx->buf_len != ctx->buf_off) |
| 509 | { |
| 510 | memmove(ctx->buf, &(ctx->buf[ctx->buf_off]), ctx->buf_len- ctx->buf_off); |
| 511 | } |
| 512 | ctx->buf_len-= ctx->buf_off; |
| 513 | ctx->buf_off= 0; |
| 514 | } |
| 515 | else |
| 516 | { |
| 517 | ctx->cont= 0; |
| 518 | } |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 519 | } |
| 520 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 521 | static void block_out(BIO* b) |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 522 | { |
| 523 | BIO_OK_CTX *ctx; |
| 524 | EVP_MD_CTX *md; |
| 525 | unsigned long tl; |
| 526 | |
| 527 | ctx=b->ptr; |
| 528 | md=&ctx->md; |
| 529 | |
| 530 | tl= ctx->buf_len- OK_BLOCK_BLOCK; |
| 531 | ctx->buf[0]=(unsigned char)(tl>>24); |
| 532 | ctx->buf[1]=(unsigned char)(tl>>16); |
| 533 | ctx->buf[2]=(unsigned char)(tl>>8); |
| 534 | ctx->buf[3]=(unsigned char)(tl); |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 535 | EVP_DigestUpdate(md, (unsigned char*) &(ctx->buf[OK_BLOCK_BLOCK]), tl); |
| 536 | EVP_DigestFinal_ex(md, &(ctx->buf[ctx->buf_len]), NULL); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 537 | ctx->buf_len+= md->digest->md_size; |
| 538 | ctx->blockout= 1; |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 539 | } |
| 540 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 541 | static void block_in(BIO* b) |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 542 | { |
| 543 | BIO_OK_CTX *ctx; |
| 544 | EVP_MD_CTX *md; |
| 545 | unsigned long tl= 0; |
| 546 | unsigned char tmp[EVP_MAX_MD_SIZE]; |
| 547 | |
| 548 | ctx=b->ptr; |
| 549 | md=&ctx->md; |
| 550 | |
| 551 | assert(sizeof(tl)>=OK_BLOCK_BLOCK); /* always true */ |
| 552 | tl =ctx->buf[0]; tl<<=8; |
| 553 | tl|=ctx->buf[1]; tl<<=8; |
| 554 | tl|=ctx->buf[2]; tl<<=8; |
| 555 | tl|=ctx->buf[3]; |
| 556 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 557 | if (ctx->buf_len < tl+ OK_BLOCK_BLOCK+ md->digest->md_size) return; |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 558 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 559 | EVP_DigestUpdate(md, (unsigned char*) &(ctx->buf[OK_BLOCK_BLOCK]), tl); |
| 560 | EVP_DigestFinal_ex(md, tmp, NULL); |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 561 | if(memcmp(&(ctx->buf[tl+ OK_BLOCK_BLOCK]), tmp, md->digest->md_size) == 0) |
| 562 | { |
| 563 | /* there might be parts from next block lurking around ! */ |
| 564 | ctx->buf_off_save= tl+ OK_BLOCK_BLOCK+ md->digest->md_size; |
| 565 | ctx->buf_len_save= ctx->buf_len; |
| 566 | ctx->buf_off= OK_BLOCK_BLOCK; |
| 567 | ctx->buf_len= tl+ OK_BLOCK_BLOCK; |
| 568 | ctx->blockout= 1; |
| 569 | } |
| 570 | else |
| 571 | { |
| 572 | ctx->cont= 0; |
| 573 | } |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 574 | } |
| 575 | |