uri.cc 15 KB
Newer Older
1 2 3 4 5 6
// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "src/uri.h"

7 8
#include <vector>

9 10
#include "src/char-predicates-inl.h"
#include "src/isolate-inl.h"
11
#include "src/string-search.h"
12
#include "src/unicode-inl.h"
13 14 15 16

namespace v8 {
namespace internal {

17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39
namespace {  // anonymous namespace for DecodeURI helper functions
bool IsReservedPredicate(uc16 c) {
  switch (c) {
    case '#':
    case '$':
    case '&':
    case '+':
    case ',':
    case '/':
    case ':':
    case ';':
    case '=':
    case '?':
    case '@':
      return true;
    default:
      return false;
  }
}

bool IsReplacementCharacter(const uint8_t* octets, int length) {
  // The replacement character is at codepoint U+FFFD in the Unicode Specials
  // table. Its UTF-8 encoding is 0xEF 0xBF 0xBD.
40 41
  if (length != 3 || octets[0] != 0xEF || octets[1] != 0xBF ||
      octets[2] != 0xBD) {
42 43 44 45 46
    return false;
  }
  return true;
}

47 48
bool DecodeOctets(const uint8_t* octets, int length,
                  std::vector<uc16>* buffer) {
49 50 51 52 53 54 55
  size_t cursor = 0;
  uc32 value = unibrow::Utf8::ValueOf(octets, length, &cursor);
  if (value == unibrow::Utf8::kBadChar &&
      !IsReplacementCharacter(octets, length)) {
    return false;
  }

56
  if (value <= static_cast<uc32>(unibrow::Utf16::kMaxNonSurrogateCharCode)) {
57
    buffer->push_back(value);
58
  } else {
59 60
    buffer->push_back(unibrow::Utf16::LeadSurrogate(value));
    buffer->push_back(unibrow::Utf16::TrailSurrogate(value));
61 62 63 64
  }
  return true;
}

65 66 67 68 69 70 71 72
int TwoDigitHex(uc16 character1, uc16 character2) {
  if (character1 > 'f') return -1;
  int high = HexValue(character1);
  if (high == -1) return -1;
  if (character2 > 'f') return -1;
  int low = HexValue(character2);
  if (low == -1) return -1;
  return (high << 4) + low;
73 74 75 76
}

template <typename T>
void AddToBuffer(uc16 decoded, String::FlatContent* uri_content, int index,
77
                 bool is_uri, std::vector<T>* buffer) {
78
  if (is_uri && IsReservedPredicate(decoded)) {
79
    buffer->push_back('%');
80 81 82 83 84
    uc16 first = uri_content->Get(index + 1);
    uc16 second = uri_content->Get(index + 2);
    DCHECK_GT(std::numeric_limits<T>::max(), first);
    DCHECK_GT(std::numeric_limits<T>::max(), second);

85 86
    buffer->push_back(first);
    buffer->push_back(second);
87
  } else {
88
    buffer->push_back(decoded);
89 90 91 92
  }
}

bool IntoTwoByte(int index, bool is_uri, int uri_length,
93
                 String::FlatContent* uri_content, std::vector<uc16>* buffer) {
94 95 96
  for (int k = index; k < uri_length; k++) {
    uc16 code = uri_content->Get(k);
    if (code == '%') {
97
      int two_digits;
98
      if (k + 2 >= uri_length ||
99 100
          (two_digits = TwoDigitHex(uri_content->Get(k + 1),
                                    uri_content->Get(k + 2))) < 0) {
101 102 103
        return false;
      }
      k += 2;
104
      uc16 decoded = static_cast<uc16>(two_digits);
105 106 107 108 109 110 111 112 113 114
      if (decoded > unibrow::Utf8::kMaxOneByteChar) {
        uint8_t octets[unibrow::Utf8::kMaxEncodedSize];
        octets[0] = decoded;

        int number_of_continuation_bytes = 0;
        while ((decoded << ++number_of_continuation_bytes) & 0x80) {
          if (number_of_continuation_bytes > 3 || k + 3 >= uri_length) {
            return false;
          }
          if (uri_content->Get(++k) != '%' ||
115 116
              (two_digits = TwoDigitHex(uri_content->Get(k + 1),
                                        uri_content->Get(k + 2))) < 0) {
117 118 119
            return false;
          }
          k += 2;
120
          uc16 continuation_byte = static_cast<uc16>(two_digits);
121 122 123 124 125 126 127 128 129 130
          octets[number_of_continuation_bytes] = continuation_byte;
        }

        if (!DecodeOctets(octets, number_of_continuation_bytes, buffer)) {
          return false;
        }
      } else {
        AddToBuffer(decoded, uri_content, k - 2, is_uri, buffer);
      }
    } else {
131
      buffer->push_back(code);
132 133 134 135 136 137
    }
  }
  return true;
}

bool IntoOneAndTwoByte(Handle<String> uri, bool is_uri,
138 139
                       std::vector<uint8_t>* one_byte_buffer,
                       std::vector<uc16>* two_byte_buffer) {
140
  DisallowHeapAllocation no_gc;
141
  String::FlatContent uri_content = uri->GetFlatContent(no_gc);
142 143 144 145 146

  int uri_length = uri->length();
  for (int k = 0; k < uri_length; k++) {
    uc16 code = uri_content.Get(k);
    if (code == '%') {
147
      int two_digits;
148
      if (k + 2 >= uri_length ||
149 150
          (two_digits = TwoDigitHex(uri_content.Get(k + 1),
                                    uri_content.Get(k + 2))) < 0) {
151 152 153
        return false;
      }

154
      uc16 decoded = static_cast<uc16>(two_digits);
155 156 157 158 159 160 161 162 163 164 165 166
      if (decoded > unibrow::Utf8::kMaxOneByteChar) {
        return IntoTwoByte(k, is_uri, uri_length, &uri_content,
                           two_byte_buffer);
      }

      AddToBuffer(decoded, &uri_content, k, is_uri, one_byte_buffer);
      k += 2;
    } else {
      if (code > unibrow::Utf8::kMaxOneByteChar) {
        return IntoTwoByte(k, is_uri, uri_length, &uri_content,
                           two_byte_buffer);
      }
167
      one_byte_buffer->push_back(code);
168 169 170 171 172 173 174 175 176
    }
  }
  return true;
}

}  // anonymous namespace

MaybeHandle<String> Uri::Decode(Isolate* isolate, Handle<String> uri,
                                bool is_uri) {
177
  uri = String::Flatten(isolate, uri);
178 179
  std::vector<uint8_t> one_byte_buffer;
  std::vector<uc16> two_byte_buffer;
180 181 182 183 184

  if (!IntoOneAndTwoByte(uri, is_uri, &one_byte_buffer, &two_byte_buffer)) {
    THROW_NEW_ERROR(isolate, NewURIError(), String);
  }

185 186 187
  if (two_byte_buffer.empty()) {
    return isolate->factory()->NewStringFromOneByte(Vector<const uint8_t>(
        one_byte_buffer.data(), static_cast<int>(one_byte_buffer.size())));
188 189 190
  }

  Handle<SeqTwoByteString> result;
191 192
  int result_length =
      static_cast<int>(one_byte_buffer.size() + two_byte_buffer.size());
193
  ASSIGN_RETURN_ON_EXCEPTION(
194
      isolate, result, isolate->factory()->NewRawTwoByteString(result_length),
195 196
      String);

197
  DisallowHeapAllocation no_gc;
198 199 200 201
  CopyChars(result->GetChars(no_gc), one_byte_buffer.data(),
            one_byte_buffer.size());
  CopyChars(result->GetChars(no_gc) + one_byte_buffer.size(),
            two_byte_buffer.data(), two_byte_buffer.size());
202 203 204 205

  return result;
}

206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246
namespace {  // anonymous namespace for EncodeURI helper functions
bool IsUnescapePredicateInUriComponent(uc16 c) {
  if (IsAlphaNumeric(c)) {
    return true;
  }

  switch (c) {
    case '!':
    case '\'':
    case '(':
    case ')':
    case '*':
    case '-':
    case '.':
    case '_':
    case '~':
      return true;
    default:
      return false;
  }
}

bool IsUriSeparator(uc16 c) {
  switch (c) {
    case '#':
    case ':':
    case ';':
    case '/':
    case '?':
    case '$':
    case '&':
    case '+':
    case ',':
    case '@':
    case '=':
      return true;
    default:
      return false;
  }
}

247 248 249 250
void AddEncodedOctetToBuffer(uint8_t octet, std::vector<uint8_t>* buffer) {
  buffer->push_back('%');
  buffer->push_back(HexCharOfValue(octet >> 4));
  buffer->push_back(HexCharOfValue(octet & 0x0F));
251 252
}

253
void EncodeSingle(uc16 c, std::vector<uint8_t>* buffer) {
254
  char s[4] = {};
255 256 257 258
  int number_of_bytes;
  number_of_bytes =
      unibrow::Utf8::Encode(s, c, unibrow::Utf16::kNoPreviousCharacter, false);
  for (int k = 0; k < number_of_bytes; k++) {
259
    AddEncodedOctetToBuffer(s[k], buffer);
260 261 262
  }
}

263
void EncodePair(uc16 cc1, uc16 cc2, std::vector<uint8_t>* buffer) {
264
  char s[4] = {};
265 266 267 268
  int number_of_bytes =
      unibrow::Utf8::Encode(s, unibrow::Utf16::CombineSurrogatePair(cc1, cc2),
                            unibrow::Utf16::kNoPreviousCharacter, false);
  for (int k = 0; k < number_of_bytes; k++) {
269
    AddEncodedOctetToBuffer(s[k], buffer);
270
  }
271 272 273 274
}

}  // anonymous namespace

275 276
MaybeHandle<String> Uri::Encode(Isolate* isolate, Handle<String> uri,
                                bool is_uri) {
277
  uri = String::Flatten(isolate, uri);
278
  int uri_length = uri->length();
279 280
  std::vector<uint8_t> buffer;
  buffer.reserve(uri_length);
281 282 283

  {
    DisallowHeapAllocation no_gc;
284
    String::FlatContent uri_content = uri->GetFlatContent(no_gc);
285 286 287 288 289 290 291 292 293 294 295 296 297 298 299

    for (int k = 0; k < uri_length; k++) {
      uc16 cc1 = uri_content.Get(k);
      if (unibrow::Utf16::IsLeadSurrogate(cc1)) {
        k++;
        if (k < uri_length) {
          uc16 cc2 = uri->Get(k);
          if (unibrow::Utf16::IsTrailSurrogate(cc2)) {
            EncodePair(cc1, cc2, &buffer);
            continue;
          }
        }
      } else if (!unibrow::Utf16::IsTrailSurrogate(cc1)) {
        if (IsUnescapePredicateInUriComponent(cc1) ||
            (is_uri && IsUriSeparator(cc1))) {
300
          buffer.push_back(cc1);
301 302 303 304 305 306 307
        } else {
          EncodeSingle(cc1, &buffer);
        }
        continue;
      }

      AllowHeapAllocation allocate_error_and_return;
308
      THROW_NEW_ERROR(isolate, NewURIError(), String);
309 310 311
    }
  }

312
  return isolate->factory()->NewStringFromOneByte(VectorOf(buffer));
313 314
}

315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345
namespace {  // Anonymous namespace for Escape and Unescape

template <typename Char>
int UnescapeChar(Vector<const Char> vector, int i, int length, int* step) {
  uint16_t character = vector[i];
  int32_t hi = 0;
  int32_t lo = 0;
  if (character == '%' && i <= length - 6 && vector[i + 1] == 'u' &&
      (hi = TwoDigitHex(vector[i + 2], vector[i + 3])) > -1 &&
      (lo = TwoDigitHex(vector[i + 4], vector[i + 5])) > -1) {
    *step = 6;
    return (hi << 8) + lo;
  } else if (character == '%' && i <= length - 3 &&
             (lo = TwoDigitHex(vector[i + 1], vector[i + 2])) > -1) {
    *step = 3;
    return lo;
  } else {
    *step = 1;
    return character;
  }
}

template <typename Char>
MaybeHandle<String> UnescapeSlow(Isolate* isolate, Handle<String> string,
                                 int start_index) {
  bool one_byte = true;
  int length = string->length();

  int unescaped_length = 0;
  {
    DisallowHeapAllocation no_allocation;
346
    Vector<const Char> vector = string->GetCharVector<Char>(no_allocation);
347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362
    for (int i = start_index; i < length; unescaped_length++) {
      int step;
      if (UnescapeChar(vector, i, length, &step) >
          String::kMaxOneByteCharCode) {
        one_byte = false;
      }
      i += step;
    }
  }

  DCHECK(start_index < length);
  Handle<String> first_part =
      isolate->factory()->NewProperSubString(string, 0, start_index);

  int dest_position = 0;
  Handle<String> second_part;
363
  DCHECK_LE(unescaped_length, String::kMaxLength);
364 365 366 367 368
  if (one_byte) {
    Handle<SeqOneByteString> dest = isolate->factory()
                                        ->NewRawOneByteString(unescaped_length)
                                        .ToHandleChecked();
    DisallowHeapAllocation no_allocation;
369
    Vector<const Char> vector = string->GetCharVector<Char>(no_allocation);
370 371 372 373 374 375 376 377 378 379 380 381
    for (int i = start_index; i < length; dest_position++) {
      int step;
      dest->SeqOneByteStringSet(dest_position,
                                UnescapeChar(vector, i, length, &step));
      i += step;
    }
    second_part = dest;
  } else {
    Handle<SeqTwoByteString> dest = isolate->factory()
                                        ->NewRawTwoByteString(unescaped_length)
                                        .ToHandleChecked();
    DisallowHeapAllocation no_allocation;
382
    Vector<const Char> vector = string->GetCharVector<Char>(no_allocation);
383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418
    for (int i = start_index; i < length; dest_position++) {
      int step;
      dest->SeqTwoByteStringSet(dest_position,
                                UnescapeChar(vector, i, length, &step));
      i += step;
    }
    second_part = dest;
  }
  return isolate->factory()->NewConsString(first_part, second_part);
}

bool IsNotEscaped(uint16_t c) {
  if (IsAlphaNumeric(c)) {
    return true;
  }
  //  @*_+-./
  switch (c) {
    case '@':
    case '*':
    case '_':
    case '+':
    case '-':
    case '.':
    case '/':
      return true;
    default:
      return false;
  }
}

template <typename Char>
static MaybeHandle<String> UnescapePrivate(Isolate* isolate,
                                           Handle<String> source) {
  int index;
  {
    DisallowHeapAllocation no_allocation;
419
    StringSearch<uint8_t, Char> search(isolate, StaticCharVector("%"));
420
    index = search.Search(source->GetCharVector<Char>(no_allocation), 0);
421 422 423 424 425 426 427 428 429 430 431 432 433 434
    if (index < 0) return source;
  }
  return UnescapeSlow<Char>(isolate, source, index);
}

template <typename Char>
static MaybeHandle<String> EscapePrivate(Isolate* isolate,
                                         Handle<String> string) {
  DCHECK(string->IsFlat());
  int escaped_length = 0;
  int length = string->length();

  {
    DisallowHeapAllocation no_allocation;
435
    Vector<const Char> vector = string->GetCharVector<Char>(no_allocation);
436 437 438 439 440 441 442 443 444 445 446
    for (int i = 0; i < length; i++) {
      uint16_t c = vector[i];
      if (c >= 256) {
        escaped_length += 6;
      } else if (IsNotEscaped(c)) {
        escaped_length++;
      } else {
        escaped_length += 3;
      }

      // We don't allow strings that are longer than a maximal length.
447
      DCHECK_LT(String::kMaxLength, 0x7FFFFFFF - 6);   // Cannot overflow.
448 449 450 451 452 453 454 455 456 457 458 459 460 461 462
      if (escaped_length > String::kMaxLength) break;  // Provoke exception.
    }
  }

  // No length change implies no change.  Return original string if no change.
  if (escaped_length == length) return string;

  Handle<SeqOneByteString> dest;
  ASSIGN_RETURN_ON_EXCEPTION(
      isolate, dest, isolate->factory()->NewRawOneByteString(escaped_length),
      String);
  int dest_position = 0;

  {
    DisallowHeapAllocation no_allocation;
463
    Vector<const Char> vector = string->GetCharVector<Char>(no_allocation);
464 465 466 467 468 469 470
    for (int i = 0; i < length; i++) {
      uint16_t c = vector[i];
      if (c >= 256) {
        dest->SeqOneByteStringSet(dest_position, '%');
        dest->SeqOneByteStringSet(dest_position + 1, 'u');
        dest->SeqOneByteStringSet(dest_position + 2, HexCharOfValue(c >> 12));
        dest->SeqOneByteStringSet(dest_position + 3,
471
                                  HexCharOfValue((c >> 8) & 0xF));
472
        dest->SeqOneByteStringSet(dest_position + 4,
473 474
                                  HexCharOfValue((c >> 4) & 0xF));
        dest->SeqOneByteStringSet(dest_position + 5, HexCharOfValue(c & 0xF));
475 476 477 478 479 480 481
        dest_position += 6;
      } else if (IsNotEscaped(c)) {
        dest->SeqOneByteStringSet(dest_position, c);
        dest_position++;
      } else {
        dest->SeqOneByteStringSet(dest_position, '%');
        dest->SeqOneByteStringSet(dest_position + 1, HexCharOfValue(c >> 4));
482
        dest->SeqOneByteStringSet(dest_position + 2, HexCharOfValue(c & 0xF));
483 484 485 486 487 488 489 490 491 492 493 494
        dest_position += 3;
      }
    }
  }

  return dest;
}

}  // Anonymous namespace

MaybeHandle<String> Uri::Escape(Isolate* isolate, Handle<String> string) {
  Handle<String> result;
495
  string = String::Flatten(isolate, string);
496
  return String::IsOneByteRepresentationUnderneath(*string)
497 498 499 500 501 502
             ? EscapePrivate<uint8_t>(isolate, string)
             : EscapePrivate<uc16>(isolate, string);
}

MaybeHandle<String> Uri::Unescape(Isolate* isolate, Handle<String> string) {
  Handle<String> result;
503
  string = String::Flatten(isolate, string);
504
  return String::IsOneByteRepresentationUnderneath(*string)
505 506 507 508
             ? UnescapePrivate<uint8_t>(isolate, string)
             : UnescapePrivate<uc16>(isolate, string);
}

509 510
}  // namespace internal
}  // namespace v8