lib/libcrypto/bio/bf_buff.c

   1 /* $OpenBSD: bf_buff.c,v 1.25 2018/05/01 13:29:09 tb Exp $ */
   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 #include <errno.h>
  60 #include <stdio.h>
  61 #include <string.h>
  62
  63 #include <openssl/bio.h>
  64 #include <openssl/err.h>
  65
  66 static int buffer_write(BIO *h, const char *buf, int num);
  67 static int buffer_read(BIO *h, char *buf, int size);
  68 static int buffer_puts(BIO *h, const char *str);
  69 static int buffer_gets(BIO *h, char *str, int size);
  70 static long buffer_ctrl(BIO *h, int cmd, long arg1, void *arg2);
  71 static int buffer_new(BIO *h);
  72 static int buffer_free(BIO *data);
  73 static long buffer_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp);
  74 #define DEFAULT_BUFFER_SIZE     4096
  75
  76 static const BIO_METHOD methods_buffer = {
  77         .type = BIO_TYPE_BUFFER,
  78         .name = "buffer",
  79         .bwrite = buffer_write,
  80         .bread = buffer_read,
  81         .bputs = buffer_puts,
  82         .bgets = buffer_gets,
  83         .ctrl = buffer_ctrl,
  84         .create = buffer_new,
  85         .destroy = buffer_free,
  86         .callback_ctrl = buffer_callback_ctrl
  87 };
  88
  89 const BIO_METHOD *
  90 BIO_f_buffer(void)
  91 {
  92         return (&methods_buffer);
  93 }
  94
  95 static int
  96 buffer_new(BIO *bi)
  97 {
  98         BIO_F_BUFFER_CTX *ctx;
  99
 100         ctx = malloc(sizeof(BIO_F_BUFFER_CTX));
 101         if (ctx == NULL)
 102                 return (0);
 103         ctx->ibuf = malloc(DEFAULT_BUFFER_SIZE);
 104         if (ctx->ibuf == NULL) {
 105                 free(ctx);
 106                 return (0);
 107         }
 108         ctx->obuf = malloc(DEFAULT_BUFFER_SIZE);
 109         if (ctx->obuf == NULL) {
 110                 free(ctx->ibuf);
 111                 free(ctx);
 112                 return (0);
 113         }
 114         ctx->ibuf_size = DEFAULT_BUFFER_SIZE;
 115         ctx->obuf_size = DEFAULT_BUFFER_SIZE;
 116         ctx->ibuf_len = 0;
 117         ctx->ibuf_off = 0;
 118         ctx->obuf_len = 0;
 119         ctx->obuf_off = 0;
 120
 121         bi->init = 1;
 122         bi->ptr = (char *)ctx;
 123         bi->flags = 0;
 124         return (1);
 125 }
 126
 127 static int
 128 buffer_free(BIO *a)
 129 {
 130         BIO_F_BUFFER_CTX *b;
 131
 132         if (a == NULL)
 133                 return (0);
 134         b = (BIO_F_BUFFER_CTX *)a->ptr;
 135         free(b->ibuf);
 136         free(b->obuf);
 137         free(a->ptr);
 138         a->ptr = NULL;
 139         a->init = 0;
 140         a->flags = 0;
 141         return (1);
 142 }
 143
 144 static int
 145 buffer_read(BIO *b, char *out, int outl)
 146 {
 147         int i, num = 0;
 148         BIO_F_BUFFER_CTX *ctx;
 149
 150         if (out == NULL)
 151                 return (0);
 152         ctx = (BIO_F_BUFFER_CTX *)b->ptr;
 153
 154         if ((ctx == NULL) || (b->next_bio == NULL))
 155                 return (0);
 156         num = 0;
 157         BIO_clear_retry_flags(b);
 158
 159 start:
 160         i = ctx->ibuf_len;
 161         /* If there is stuff left over, grab it */
 162         if (i != 0) {
 163                 if (i > outl)
 164                         i = outl;
 165                 memcpy(out, &(ctx->ibuf[ctx->ibuf_off]), i);
 166                 ctx->ibuf_off += i;
 167                 ctx->ibuf_len -= i;
 168                 num += i;
 169                 if (outl == i)
 170                         return (num);
 171                 outl -= i;
 172                 out += i;
 173         }
 174
 175         /* We may have done a partial read. try to do more.
 176          * We have nothing in the buffer.
 177          * If we get an error and have read some data, just return it
 178          * and let them retry to get the error again.
 179          * copy direct to parent address space */
 180         if (outl > ctx->ibuf_size) {
 181                 for (;;) {
 182                         i = BIO_read(b->next_bio, out, outl);
 183                         if (i <= 0) {
 184                                 BIO_copy_next_retry(b);
 185                                 if (i < 0)
 186                                         return ((num > 0) ? num : i);
 187                                 if (i == 0)
 188                                         return (num);
 189                         }
 190                         num += i;
 191                         if (outl == i)
 192                                 return (num);
 193                         out += i;
 194                         outl -= i;
 195                 }
 196         }
 197         /* else */
 198
 199         /* we are going to be doing some buffering */
 200         i = BIO_read(b->next_bio, ctx->ibuf, ctx->ibuf_size);
 201         if (i <= 0) {
 202                 BIO_copy_next_retry(b);
 203                 if (i < 0)
 204                         return ((num > 0) ? num : i);
 205                 if (i == 0)
 206                         return (num);
 207         }
 208         ctx->ibuf_off = 0;
 209         ctx->ibuf_len = i;
 210
 211         /* Lets re-read using ourselves :-) */
 212         goto start;
 213 }
 214
 215 static int
 216 buffer_write(BIO *b, const char *in, int inl)
 217 {
 218         int i, num = 0;
 219         BIO_F_BUFFER_CTX *ctx;
 220
 221         if ((in == NULL) || (inl <= 0))
 222                 return (0);
 223         ctx = (BIO_F_BUFFER_CTX *)b->ptr;
 224         if ((ctx == NULL) || (b->next_bio == NULL))
 225                 return (0);
 226
 227         BIO_clear_retry_flags(b);
 228 start:
 229         i = ctx->obuf_size - (ctx->obuf_len + ctx->obuf_off);
 230         /* add to buffer and return */
 231         if (i >= inl) {
 232                 memcpy(&(ctx->obuf[ctx->obuf_off + ctx->obuf_len]), in, inl);
 233                 ctx->obuf_len += inl;
 234                 return (num + inl);
 235         }
 236         /* else */
 237         /* stuff already in buffer, so add to it first, then flush */
 238         if (ctx->obuf_len != 0) {
 239                 if (i > 0) /* lets fill it up if we can */
 240                 {
 241                         memcpy(&(ctx->obuf[ctx->obuf_off + ctx->obuf_len]), in, i);
 242                         in += i;
 243                         inl -= i;
 244                         num += i;
 245                         ctx->obuf_len += i;
 246                 }
 247                 /* we now have a full buffer needing flushing */
 248                 for (;;) {
 249                         i = BIO_write(b->next_bio, &(ctx->obuf[ctx->obuf_off]),
 250                             ctx->obuf_len);
 251                         if (i <= 0) {
 252                                 BIO_copy_next_retry(b);
 253
 254                                 if (i < 0)
 255                                         return ((num > 0) ? num : i);
 256                                 if (i == 0)
 257                                         return (num);
 258                         }
 259                         ctx->obuf_off += i;
 260                         ctx->obuf_len -= i;
 261                         if (ctx->obuf_len == 0)
 262                                 break;
 263                 }
 264         }
 265         /* we only get here if the buffer has been flushed and we
 266          * still have stuff to write */
 267         ctx->obuf_off = 0;
 268
 269         /* we now have inl bytes to write */
 270         while (inl >= ctx->obuf_size) {
 271                 i = BIO_write(b->next_bio, in, inl);
 272                 if (i <= 0) {
 273                         BIO_copy_next_retry(b);
 274                         if (i < 0)
 275                                 return ((num > 0) ? num : i);
 276                         if (i == 0)
 277                                 return (num);
 278                 }
 279                 num += i;
 280                 in += i;
 281                 inl -= i;
 282                 if (inl == 0)
 283                         return (num);
 284         }
 285
 286         /* copy the rest into the buffer since we have only a small
 287          * amount left */
 288         goto start;
 289 }
 290
 291 static long
 292 buffer_ctrl(BIO *b, int cmd, long num, void *ptr)
 293 {
 294         BIO *dbio;
 295         BIO_F_BUFFER_CTX *ctx;
 296         long ret = 1;
 297         char *p1, *p2;
 298         int r, i, *ip;
 299         int ibs, obs;
 300
 301         ctx = (BIO_F_BUFFER_CTX *)b->ptr;
 302
 303         switch (cmd) {
 304         case BIO_CTRL_RESET:
 305                 ctx->ibuf_off = 0;
 306                 ctx->ibuf_len = 0;
 307                 ctx->obuf_off = 0;
 308                 ctx->obuf_len = 0;
 309                 if (b->next_bio == NULL)
 310                         return (0);
 311                 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 312                 break;
 313         case BIO_CTRL_INFO:
 314                 ret = (long)ctx->obuf_len;
 315                 break;
 316         case BIO_C_GET_BUFF_NUM_LINES:
 317                 ret = 0;
 318                 p1 = ctx->ibuf;
 319                 for (i = 0; i < ctx->ibuf_len; i++) {
 320                         if (p1[ctx->ibuf_off + i] == '\n')
 321                                 ret++;
 322                 }
 323                 break;
 324         case BIO_CTRL_WPENDING:
 325                 ret = (long)ctx->obuf_len;
 326                 if (ret == 0) {
 327                         if (b->next_bio == NULL)
 328                                 return (0);
 329                         ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 330                 }
 331                 break;
 332         case BIO_CTRL_PENDING:
 333                 ret = (long)ctx->ibuf_len;
 334                 if (ret == 0) {
 335                         if (b->next_bio == NULL)
 336                                 return (0);
 337                         ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 338                 }
 339                 break;
 340         case BIO_C_SET_BUFF_READ_DATA:
 341                 if (num > ctx->ibuf_size) {
 342                         p1 = malloc(num);
 343                         if (p1 == NULL)
 344                                 goto malloc_error;
 345                         free(ctx->ibuf);
 346                         ctx->ibuf = p1;
 347                 }
 348                 ctx->ibuf_off = 0;
 349                 ctx->ibuf_len = (int)num;
 350                 memcpy(ctx->ibuf, ptr, num);
 351                 ret = 1;
 352                 break;
 353         case BIO_C_SET_BUFF_SIZE:
 354                 if (ptr != NULL) {
 355                         ip = (int *)ptr;
 356                         if (*ip == 0) {
 357                                 ibs = (int)num;
 358                                 obs = ctx->obuf_size;
 359                         }
 360                         else /* if (*ip == 1) */
 361                         {
 362                                 ibs = ctx->ibuf_size;
 363                                 obs = (int)num;
 364                         }
 365                 } else {
 366                         ibs = (int)num;
 367                         obs = (int)num;
 368                 }
 369                 p1 = ctx->ibuf;
 370                 p2 = ctx->obuf;
 371                 if ((ibs > DEFAULT_BUFFER_SIZE) && (ibs != ctx->ibuf_size)) {
 372                         p1 = malloc(num);
 373                         if (p1 == NULL)
 374                                 goto malloc_error;
 375                 }
 376                 if ((obs > DEFAULT_BUFFER_SIZE) && (obs != ctx->obuf_size)) {
 377                         p2 = malloc(num);
 378                         if (p2 == NULL) {
 379                                 if (p1 != ctx->ibuf)
 380                                         free(p1);
 381                                 goto malloc_error;
 382                         }
 383                 }
 384                 if (ctx->ibuf != p1) {
 385                         free(ctx->ibuf);
 386                         ctx->ibuf = p1;
 387                         ctx->ibuf_off = 0;
 388                         ctx->ibuf_len = 0;
 389                         ctx->ibuf_size = ibs;
 390                 }
 391                 if (ctx->obuf != p2) {
 392                         free(ctx->obuf);
 393                         ctx->obuf = p2;
 394                         ctx->obuf_off = 0;
 395                         ctx->obuf_len = 0;
 396                         ctx->obuf_size = obs;
 397                 }
 398                 break;
 399         case BIO_C_DO_STATE_MACHINE:
 400                 if (b->next_bio == NULL)
 401                         return (0);
 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
 407         case BIO_CTRL_FLUSH:
 408                 if (b->next_bio == NULL)
 409                         return (0);
 410                 if (ctx->obuf_len <= 0) {
 411                         ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 412                         break;
 413                 }
 414
 415                 for (;;) {
 416                         BIO_clear_retry_flags(b);
 417                         if (ctx->obuf_len > 0) {
 418                                 r = BIO_write(b->next_bio,
 419                                     &(ctx->obuf[ctx->obuf_off]),
 420                                     ctx->obuf_len);
 421                                 BIO_copy_next_retry(b);
 422                                 if (r <= 0)
 423                                         return ((long)r);
 424                                 ctx->obuf_off += r;
 425                                 ctx->obuf_len -= r;
 426                         } else {
 427                                 ctx->obuf_len = 0;
 428                                 ctx->obuf_off = 0;
 429                                 break;
 430                         }
 431                 }
 432                 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 433                 break;
 434         case BIO_CTRL_DUP:
 435                 dbio = (BIO *)ptr;
 436                 if (!BIO_set_read_buffer_size(dbio, ctx->ibuf_size) ||
 437                     !BIO_set_write_buffer_size(dbio, ctx->obuf_size))
 438                         ret = 0;
 439                 break;
 440         default:
 441                 if (b->next_bio == NULL)
 442                         return (0);
 443                 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 444                 break;
 445         }
 446         return (ret);
 447 malloc_error:
 448         BIOerror(ERR_R_MALLOC_FAILURE);
 449         return (0);
 450 }
 451
 452 static long
 453 buffer_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
 454 {
 455         long ret = 1;
 456
 457         if (b->next_bio == NULL)
 458                 return (0);
 459         switch (cmd) {
 460         default:
 461                 ret = BIO_callback_ctrl(b->next_bio, cmd, fp);
 462                 break;
 463         }
 464         return (ret);
 465 }
 466
 467 static int
 468 buffer_gets(BIO *b, char *buf, int size)
 469 {
 470         BIO_F_BUFFER_CTX *ctx;
 471         int num = 0, i, flag;
 472         char *p;
 473
 474         ctx = (BIO_F_BUFFER_CTX *)b->ptr;
 475         size--; /* reserve space for a '\0' */
 476         BIO_clear_retry_flags(b);
 477
 478         for (;;) {
 479                 if (ctx->ibuf_len > 0) {
 480                         p = &(ctx->ibuf[ctx->ibuf_off]);
 481                         flag = 0;
 482                         for (i = 0; (i < ctx->ibuf_len) && (i < size); i++) {
 483                                 *(buf++) = p[i];
 484                                 if (p[i] == '\n') {
 485                                         flag = 1;
 486                                         i++;
 487                                         break;
 488                                 }
 489                         }
 490                         num += i;
 491                         size -= i;
 492                         ctx->ibuf_len -= i;
 493                         ctx->ibuf_off += i;
 494                         if (flag || size == 0) {
 495                                 *buf = '\0';
 496                                 return (num);
 497                         }
 498                 }
 499                 else    /* read another chunk */
 500                 {
 501                         i = BIO_read(b->next_bio, ctx->ibuf, ctx->ibuf_size);
 502                         if (i <= 0) {
 503                                 BIO_copy_next_retry(b);
 504                                 *buf = '\0';
 505                                 if (i < 0)
 506                                         return ((num > 0) ? num : i);
 507                                 if (i == 0)
 508                                         return (num);
 509                         }
 510                         ctx->ibuf_len = i;
 511                         ctx->ibuf_off = 0;
 512                 }
 513         }
 514 }
 515
 516 static int
 517 buffer_puts(BIO *b, const char *str)
 518 {
 519         return (buffer_write(b, str, strlen(str)));
 520 }