common/lib/libprop/prop_data.c

   1 /*      $NetBSD: prop_data.c,v 1.13 2008/08/03 04:00:12 thorpej Exp $   */
   2
   3 /*-
   4  * Copyright (c) 2006 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Jason R. Thorpe.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include <prop/prop_data.h>
  33 #include "prop_object_impl.h"
  34
  35 #if defined(_KERNEL)
  36 #include <sys/systm.h>
  37 #elif defined(_STANDALONE)
  38 #include <sys/param.h>
  39 #include <lib/libkern/libkern.h>
  40 #else
  41 #include <errno.h>
  42 #include <limits.h>
  43 #include <stdlib.h>
  44 #endif
  45
  46 struct _prop_data {
  47         struct _prop_object     pd_obj;
  48         union {
  49                 void *          pdu_mutable;
  50                 const void *    pdu_immutable;
  51         } pd_un;
  52 #define pd_mutable              pd_un.pdu_mutable
  53 #define pd_immutable            pd_un.pdu_immutable
  54         size_t                  pd_size;
  55         int                     pd_flags;
  56 };
  57
  58 #define PD_F_NOCOPY             0x01
  59
  60 _PROP_POOL_INIT(_prop_data_pool, sizeof(struct _prop_data), "propdata")
  61
  62 _PROP_MALLOC_DEFINE(M_PROP_DATA, "prop data",
  63                     "property data container object")
  64
  65 static _prop_object_free_rv_t
  66                 _prop_data_free(prop_stack_t, prop_object_t *);
  67 static bool     _prop_data_externalize(
  68                                 struct _prop_object_externalize_context *,
  69                                 void *);
  70 static _prop_object_equals_rv_t
  71                 _prop_data_equals(prop_object_t, prop_object_t,
  72                                   void **, void **,
  73                                   prop_object_t *, prop_object_t *);
  74
  75 static const struct _prop_object_type _prop_object_type_data = {
  76         .pot_type       =       PROP_TYPE_DATA,
  77         .pot_free       =       _prop_data_free,
  78         .pot_extern     =       _prop_data_externalize,
  79         .pot_equals     =       _prop_data_equals,
  80 };
  81
  82 #define prop_object_is_data(x)          \
  83         ((x) != NULL && (x)->pd_obj.po_type == &_prop_object_type_data)
  84
  85 /* ARGSUSED */
  86 static _prop_object_free_rv_t
  87 _prop_data_free(prop_stack_t stack, prop_object_t *obj)
  88 {
  89         prop_data_t pd = *obj;
  90
  91         if ((pd->pd_flags & PD_F_NOCOPY) == 0 && pd->pd_mutable != NULL)
  92                 _PROP_FREE(pd->pd_mutable, M_PROP_DATA);
  93         _PROP_POOL_PUT(_prop_data_pool, pd);
  94
  95         return (_PROP_OBJECT_FREE_DONE);
  96 }
  97
  98 static const char _prop_data_base64[] =
  99     "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 100 static const char _prop_data_pad64 = '=';
 101
 102 static bool
 103 _prop_data_externalize(struct _prop_object_externalize_context *ctx, void *v)
 104 {
 105         prop_data_t pd = v;
 106         size_t i, srclen;
 107         const uint8_t *src;
 108         uint8_t output[4];
 109         uint8_t input[3];
 110
 111         if (pd->pd_size == 0)
 112                 return (_prop_object_externalize_empty_tag(ctx, "data"));
 113
 114         if (_prop_object_externalize_start_tag(ctx, "data") == false)
 115                 return (false);
 116
 117         for (src = pd->pd_immutable, srclen = pd->pd_size;
 118              srclen > 2; srclen -= 3) {
 119                 input[0] = *src++;
 120                 input[1] = *src++;
 121                 input[2] = *src++;
 122
 123                 output[0] = (uint32_t)input[0] >> 2;
 124                 output[1] = ((uint32_t)(input[0] & 0x03) << 4) +
 125                     ((uint32_t)input[1] >> 4);
 126                 output[2] = ((uint32_t)(input[1] & 0x0f) << 2) +
 127                     ((uint32_t)input[2] >> 6);
 128                 output[3] = input[2] & 0x3f;
 129                 _PROP_ASSERT(output[0] < 64);
 130                 _PROP_ASSERT(output[1] < 64);
 131                 _PROP_ASSERT(output[2] < 64);
 132                 _PROP_ASSERT(output[3] < 64);
 133
 134                 if (_prop_object_externalize_append_char(ctx,
 135                                 _prop_data_base64[output[0]]) == false ||
 136                     _prop_object_externalize_append_char(ctx,
 137                                 _prop_data_base64[output[1]]) == false ||
 138                     _prop_object_externalize_append_char(ctx,
 139                                 _prop_data_base64[output[2]]) == false ||
 140                     _prop_object_externalize_append_char(ctx,
 141                                 _prop_data_base64[output[3]]) == false)
 142                         return (false);
 143         }
 144
 145         if (srclen != 0) {
 146                 input[0] = input[1] = input[2] = '\0';
 147                 for (i = 0; i < srclen; i++)
 148                         input[i] = *src++;
 149
 150                 output[0] = (uint32_t)input[0] >> 2;
 151                 output[1] = ((uint32_t)(input[0] & 0x03) << 4) +
 152                     ((uint32_t)input[1] >> 4);
 153                 output[2] = ((uint32_t)(input[1] & 0x0f) << 2) +
 154                     ((uint32_t)input[2] >> 6);
 155                 _PROP_ASSERT(output[0] < 64);
 156                 _PROP_ASSERT(output[1] < 64);
 157                 _PROP_ASSERT(output[2] < 64);
 158
 159                 if (_prop_object_externalize_append_char(ctx,
 160                                 _prop_data_base64[output[0]]) == false ||
 161                     _prop_object_externalize_append_char(ctx,
 162                                 _prop_data_base64[output[1]]) == false ||
 163                     _prop_object_externalize_append_char(ctx,
 164                                 srclen == 1 ? _prop_data_pad64
 165                                 : _prop_data_base64[output[2]]) == false ||
 166                     _prop_object_externalize_append_char(ctx,
 167                                 _prop_data_pad64) == false)
 168                         return (false);
 169         }
 170
 171         if (_prop_object_externalize_end_tag(ctx, "data") == false)
 172                 return (false);
 173
 174         return (true);
 175 }
 176
 177 /* ARGSUSED */
 178 static _prop_object_equals_rv_t
 179 _prop_data_equals(prop_object_t v1, prop_object_t v2,
 180     void **stored_pointer1, void **stored_pointer2,
 181     prop_object_t *next_obj1, prop_object_t *next_obj2)
 182 {
 183         prop_data_t pd1 = v1;
 184         prop_data_t pd2 = v2;
 185
 186         if (pd1 == pd2)
 187                 return (_PROP_OBJECT_EQUALS_TRUE);
 188         if (pd1->pd_size != pd2->pd_size)
 189                 return (_PROP_OBJECT_EQUALS_FALSE);
 190         if (pd1->pd_size == 0) {
 191                 _PROP_ASSERT(pd1->pd_immutable == NULL);
 192                 _PROP_ASSERT(pd2->pd_immutable == NULL);
 193                 return (_PROP_OBJECT_EQUALS_TRUE);
 194         }
 195         if (memcmp(pd1->pd_immutable, pd2->pd_immutable, pd1->pd_size) == 0)
 196                 return _PROP_OBJECT_EQUALS_TRUE;
 197         else
 198                 return _PROP_OBJECT_EQUALS_FALSE;
 199 }
 200
 201 static prop_data_t
 202 _prop_data_alloc(void)
 203 {
 204         prop_data_t pd;
 205
 206         pd = _PROP_POOL_GET(_prop_data_pool);
 207         if (pd != NULL) {
 208                 _prop_object_init(&pd->pd_obj, &_prop_object_type_data);
 209
 210                 pd->pd_mutable = NULL;
 211                 pd->pd_size = 0;
 212                 pd->pd_flags = 0;
 213         }
 214
 215         return (pd);
 216 }
 217
 218 /*
 219  * prop_data_create_data --
 220  *      Create a data container that contains a copy of the data.
 221  */
 222 prop_data_t
 223 prop_data_create_data(const void *v, size_t size)
 224 {
 225         prop_data_t pd;
 226         void *nv;
 227
 228         pd = _prop_data_alloc();
 229         if (pd != NULL && size != 0) {
 230                 nv = _PROP_MALLOC(size, M_PROP_DATA);
 231                 if (nv == NULL) {
 232                         prop_object_release(pd);
 233                         return (NULL);
 234                 }
 235                 memcpy(nv, v, size);
 236                 pd->pd_mutable = nv;
 237                 pd->pd_size = size;
 238         }
 239         return (pd);
 240 }
 241
 242 /*
 243  * prop_data_create_data_nocopy --
 244  *      Create an immutable data container that contains a refrence to the
 245  *      provided external data.
 246  */
 247 prop_data_t
 248 prop_data_create_data_nocopy(const void *v, size_t size)
 249 {
 250         prop_data_t pd;
 251
 252         pd = _prop_data_alloc();
 253         if (pd != NULL) {
 254                 pd->pd_immutable = v;
 255                 pd->pd_size = size;
 256                 pd->pd_flags |= PD_F_NOCOPY;
 257         }
 258         return (pd);
 259 }
 260
 261 /*
 262  * prop_data_copy --
 263  *      Copy a data container.  If the original data is external, then
 264  *      the copy is also references the same external data.
 265  */
 266 prop_data_t
 267 prop_data_copy(prop_data_t opd)
 268 {
 269         prop_data_t pd;
 270
 271         if (! prop_object_is_data(opd))
 272                 return (NULL);
 273
 274         pd = _prop_data_alloc();
 275         if (pd != NULL) {
 276                 pd->pd_size = opd->pd_size;
 277                 pd->pd_flags = opd->pd_flags;
 278                 if (opd->pd_flags & PD_F_NOCOPY)
 279                         pd->pd_immutable = opd->pd_immutable;
 280                 else if (opd->pd_size != 0) {
 281                         void *nv = _PROP_MALLOC(pd->pd_size, M_PROP_DATA);
 282                         if (nv == NULL) {
 283                                 prop_object_release(pd);
 284                                 return (NULL);
 285                         }
 286                         memcpy(nv, opd->pd_immutable, opd->pd_size);
 287                         pd->pd_mutable = nv;
 288                 }
 289         }
 290         return (pd);
 291 }
 292
 293 /*
 294  * prop_data_size --
 295  *      Return the size of the data.
 296  */
 297 size_t
 298 prop_data_size(prop_data_t pd)
 299 {
 300
 301         if (! prop_object_is_data(pd))
 302                 return (0);
 303
 304         return (pd->pd_size);
 305 }
 306
 307 /*
 308  * prop_data_data --
 309  *      Return a copy of the contents of the data container.
 310  *      The data is allocated with the M_TEMP malloc type.
 311  *      If the data container is empty, NULL is returned.
 312  */
 313 void *
 314 prop_data_data(prop_data_t pd)
 315 {
 316         void *v;
 317
 318         if (! prop_object_is_data(pd))
 319                 return (NULL);
 320
 321         if (pd->pd_size == 0) {
 322                 _PROP_ASSERT(pd->pd_immutable == NULL);
 323                 return (NULL);
 324         }
 325
 326         _PROP_ASSERT(pd->pd_immutable != NULL);
 327
 328         v = _PROP_MALLOC(pd->pd_size, M_TEMP);
 329         if (v != NULL)
 330                 memcpy(v, pd->pd_immutable, pd->pd_size);
 331
 332         return (v);
 333 }
 334
 335 /*
 336  * prop_data_data_nocopy --
 337  *      Return an immutable reference to the contents of the data
 338  *      container.
 339  */
 340 const void *
 341 prop_data_data_nocopy(prop_data_t pd)
 342 {
 343
 344         if (! prop_object_is_data(pd))
 345                 return (NULL);
 346
 347         _PROP_ASSERT((pd->pd_size == 0 && pd->pd_immutable == NULL) ||
 348                      (pd->pd_size != 0 && pd->pd_immutable != NULL));
 349
 350         return (pd->pd_immutable);
 351 }
 352
 353 /*
 354  * prop_data_equals --
 355  *      Return true if two strings are equivalent.
 356  */
 357 bool
 358 prop_data_equals(prop_data_t pd1, prop_data_t pd2)
 359 {
 360         if (!prop_object_is_data(pd1) || !prop_object_is_data(pd2))
 361                 return (false);
 362
 363         return (prop_object_equals(pd1, pd2));
 364 }
 365
 366 /*
 367  * prop_data_equals_data --
 368  *      Return true if the contained data is equivalent to the specified
 369  *      external data.
 370  */
 371 bool
 372 prop_data_equals_data(prop_data_t pd, const void *v, size_t size)
 373 {
 374
 375         if (! prop_object_is_data(pd))
 376                 return (false);
 377
 378         if (pd->pd_size != size)
 379                 return (false);
 380         return (memcmp(pd->pd_immutable, v, size) == 0);
 381 }
 382
 383 static bool
 384 _prop_data_internalize_decode(struct _prop_object_internalize_context *ctx,
 385                              uint8_t *target, size_t targsize, size_t *sizep,
 386                              const char **cpp)
 387 {
 388         const char *src;
 389         size_t tarindex;
 390         int state, ch;
 391         const char *pos;
 392
 393         state = 0;
 394         tarindex = 0;
 395         src = ctx->poic_cp;
 396
 397         for (;;) {
 398                 ch = (unsigned char) *src++;
 399                 if (_PROP_EOF(ch))
 400                         return (false);
 401                 if (_PROP_ISSPACE(ch))
 402                         continue;
 403                 if (ch == '<') {
 404                         src--;
 405                         break;
 406                 }
 407                 if (ch == _prop_data_pad64)
 408                         break;
 409
 410                 pos = strchr(_prop_data_base64, ch);
 411                 if (pos == NULL)
 412                         return (false);
 413
 414                 switch (state) {
 415                 case 0:
 416                         if (target) {
 417                                 if (tarindex >= targsize)
 418                                         return (false);
 419                                 target[tarindex] =
 420                                     (uint8_t)((pos - _prop_data_base64) << 2);
 421                         }
 422                         state = 1;
 423                         break;
 424
 425                 case 1:
 426                         if (target) {
 427                                 if (tarindex + 1 >= targsize)
 428                                         return (false);
 429                                 target[tarindex] |=
 430                                     (uint32_t)(pos - _prop_data_base64) >> 4;
 431                                 target[tarindex + 1] =
 432                                     (uint8_t)(((pos - _prop_data_base64) & 0xf)
 433                                         << 4);
 434                         }
 435                         tarindex++;
 436                         state = 2;
 437                         break;
 438
 439                 case 2:
 440                         if (target) {
 441                                 if (tarindex + 1 >= targsize)
 442                                         return (false);
 443                                 target[tarindex] |=
 444                                     (uint32_t)(pos - _prop_data_base64) >> 2;
 445                                 target[tarindex + 1] =
 446                                     (uint8_t)(((pos - _prop_data_base64)
 447                                         & 0x3) << 6);
 448                         }
 449                         tarindex++;
 450                         state = 3;
 451                         break;
 452
 453                 case 3:
 454                         if (target) {
 455                                 if (tarindex >= targsize)
 456                                         return (false);
 457                                 target[tarindex] |= (uint8_t)
 458                                     (pos - _prop_data_base64);
 459                         }
 460                         tarindex++;
 461                         state = 0;
 462                         break;
 463
 464                 default:
 465                         _PROP_ASSERT(/*CONSTCOND*/0);
 466                 }
 467         }
 468
 469         /*
 470          * We are done decoding the Base64 characters.  Let's see if we
 471          * ended up on a byte boundary and/or with unrecognized trailing
 472          * characters.
 473          */
 474         if (ch == _prop_data_pad64) {
 475                 ch = (unsigned char) *src;      /* src already advanced */
 476                 if (_PROP_EOF(ch))
 477                         return (false);
 478                 switch (state) {
 479                 case 0:         /* Invalid = in first position */
 480                 case 1:         /* Invalid = in second position */
 481                         return (false);
 482
 483                 case 2:         /* Valid, one byte of info */
 484                         /* Skip whitespace */
 485                         for (ch = (unsigned char) *src++;
 486                              ch != '<'; ch = (unsigned char) *src++) {
 487                                 if (_PROP_EOF(ch))
 488                                         return (false);
 489                                 if (!_PROP_ISSPACE(ch))
 490                                         break;
 491                         }
 492                         /* Make sure there is another trailing = */
 493                         if (ch != _prop_data_pad64)
 494                                 return (false);
 495                         ch = (unsigned char) *src;
 496                         /* FALLTHROUGH */
 497
 498                 case 3:         /* Valid, two bytes of info */
 499                         /*
 500                          * We know this char is a =.  Is there anything but
 501                          * whitespace after it?
 502                          */
 503                         for (ch = (unsigned char) *src++;
 504                              ch != '<'; ch = (unsigned char) *src++) {
 505                                 if (_PROP_EOF(ch))
 506                                         return (false);
 507                                 if (!_PROP_ISSPACE(ch))
 508                                         return (false);
 509                         }
 510                         /* back up to '<' */
 511                         src--;
 512                 }
 513         } else {
 514                 /*
 515                  * We ended by seeing the end of the Base64 string.  Make
 516                  * sure there are no partial bytes lying around.
 517                  */
 518                 if (state != 0)
 519                         return (false);
 520         }
 521
 522         _PROP_ASSERT(*src == '<');
 523         if (sizep != NULL)
 524                 *sizep = tarindex;
 525         if (cpp != NULL)
 526                 *cpp = src;
 527
 528         return (true);
 529 }
 530
 531 /*
 532  * _prop_data_internalize --
 533  *      Parse a <data>...</data> and return the object created from the
 534  *      external representation.
 535  */
 536
 537 /* strtoul is used for parsing, enforce. */
 538 typedef int PROP_DATA_ASSERT[/* CONSTCOND */sizeof(size_t) == sizeof(unsigned long) ? 1 : -1];
 539
 540 /* ARGSUSED */
 541 bool
 542 _prop_data_internalize(prop_stack_t stack, prop_object_t *obj,
 543     struct _prop_object_internalize_context *ctx)
 544 {
 545         prop_data_t data;
 546         uint8_t *buf;
 547         size_t len, alen;
 548
 549         /*
 550          * We don't accept empty elements.
 551          * This actually only checks for the node to be <data/>
 552          * (Which actually causes another error if found.)
 553          */
 554         if (ctx->poic_is_empty_element)
 555                 return (true);
 556
 557         /*
 558          * If we got a "size" attribute, get the size of the data blob
 559          * from that.  Otherwise, we have to figure it out from the base64.
 560          */
 561         if (ctx->poic_tagattr != NULL) {
 562                 char *cp;
 563
 564                 if (!_PROP_TAGATTR_MATCH(ctx, "size") ||
 565                     ctx->poic_tagattrval_len == 0)
 566                         return (true);
 567
 568 #ifndef _KERNEL
 569                 errno = 0;
 570 #endif
 571                 len = strtoul(ctx->poic_tagattrval, &cp, 0);
 572 #ifndef _KERNEL         /* XXX can't check for ERANGE in the kernel */
 573                 if (len == ULONG_MAX && errno == ERANGE)
 574                         return (true);
 575 #endif
 576                 if (cp != ctx->poic_tagattrval + ctx->poic_tagattrval_len)
 577                         return (true);
 578                 _PROP_ASSERT(*cp == '\"');
 579         } else if (_prop_data_internalize_decode(ctx, NULL, 0, &len,
 580                                                 NULL) == false)
 581                 return (true);
 582
 583         /*
 584          * Always allocate one extra in case we don't land on an even byte
 585          * boundary during the decode.
 586          */
 587         buf = _PROP_MALLOC(len + 1, M_PROP_DATA);
 588         if (buf == NULL)
 589                 return (true);
 590
 591         if (_prop_data_internalize_decode(ctx, buf, len + 1, &alen,
 592                                           &ctx->poic_cp) == false) {
 593                 _PROP_FREE(buf, M_PROP_DATA);
 594                 return (true);
 595         }
 596         if (alen != len) {
 597                 _PROP_FREE(buf, M_PROP_DATA);
 598                 return (true);
 599         }
 600
 601         if (_prop_object_internalize_find_tag(ctx, "data",
 602                                               _PROP_TAG_TYPE_END) == false) {
 603                 _PROP_FREE(buf, M_PROP_DATA);
 604                 return (true);
 605         }
 606
 607         data = _prop_data_alloc();
 608         if (data == NULL) {
 609                 _PROP_FREE(buf, M_PROP_DATA);
 610                 return (true);
 611         }
 612
 613         /*
 614          * Handle alternate type of empty node.
 615          * XML document could contain open/close tags, yet still be empty.
 616          */
 617         if (alen == 0) {
 618                 _PROP_FREE(buf, M_PROP_DATA);
 619                 data->pd_mutable = NULL;
 620         } else {
 621                 data->pd_mutable = buf;
 622         }
 623         data->pd_size = len;
 624
 625         *obj = data;
 626         return (true);
 627 }