1 files changed, 342 insertions, 0 deletions
diff --git a/security/sandbox/chromium/base/strings/utf_string_conversions.cc b/security/sandbox/chromium/base/strings/utf_string_conversions.cc
new file mode 100644
index 0000000000..9a79889159
--- /dev/null
+++ b/security/sandbox/chromium/base/strings/utf_string_conversions.cc
@@ -0,0 +1,342 @@
+// Copyright (c) 2018 The Chromium 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 "base/strings/utf_string_conversions.h"
+
+#include <limits.h>
+#include <stdint.h>
+
+#include <type_traits>
+
+#include "base/strings/string_piece.h"
+#include "base/strings/string_util.h"
+#include "base/strings/utf_string_conversion_utils.h"
+#include "base/third_party/icu/icu_utf.h"
+#include "build/build_config.h"
+
+namespace base {
+
+namespace {
+
+constexpr int32_t kErrorCodePoint = 0xFFFD;
+
+// Size coefficient ----------------------------------------------------------
+// The maximum number of codeunits in the destination encoding corresponding to
+// one codeunit in the source encoding.
+
+template <typename SrcChar, typename DestChar>
+struct SizeCoefficient {
+  static_assert(sizeof(SrcChar) < sizeof(DestChar),
+                "Default case: from a smaller encoding to the bigger one");
+
+  // ASCII symbols are encoded by one codeunit in all encodings.
+  static constexpr int value = 1;
+};
+
+template <>
+struct SizeCoefficient<char16, char> {
+  // One UTF-16 codeunit corresponds to at most 3 codeunits in UTF-8.
+  static constexpr int value = 3;
+};
+
+#if defined(WCHAR_T_IS_UTF32)
+template <>
+struct SizeCoefficient<wchar_t, char> {
+  // UTF-8 uses at most 4 codeunits per character.
+  static constexpr int value = 4;
+};
+
+template <>
+struct SizeCoefficient<wchar_t, char16> {
+  // UTF-16 uses at most 2 codeunits per character.
+  static constexpr int value = 2;
+};
+#endif  // defined(WCHAR_T_IS_UTF32)
+
+template <typename SrcChar, typename DestChar>
+constexpr int size_coefficient_v =
+    SizeCoefficient<std::decay_t<SrcChar>, std::decay_t<DestChar>>::value;
+
+// UnicodeAppendUnsafe --------------------------------------------------------
+// Function overloads that write code_point to the output string. Output string
+// has to have enough space for the codepoint.
+
+// Convenience typedef that checks whether the passed in type is integral (i.e.
+// bool, char, int or their extended versions) and is of the correct size.
+template <typename Char, size_t N>
+using EnableIfBitsAre = std::enable_if_t<std::is_integral<Char>::value &&
+                                             CHAR_BIT * sizeof(Char) == N,
+                                         bool>;
+
+template <typename Char, EnableIfBitsAre<Char, 8> = true>
+void UnicodeAppendUnsafe(Char* out, int32_t* size, uint32_t code_point) {
+  CBU8_APPEND_UNSAFE(out, *size, code_point);
+}
+
+template <typename Char, EnableIfBitsAre<Char, 16> = true>
+void UnicodeAppendUnsafe(Char* out, int32_t* size, uint32_t code_point) {
+  CBU16_APPEND_UNSAFE(out, *size, code_point);
+}
+
+template <typename Char, EnableIfBitsAre<Char, 32> = true>
+void UnicodeAppendUnsafe(Char* out, int32_t* size, uint32_t code_point) {
+  out[(*size)++] = code_point;
+}
+
+// DoUTFConversion ------------------------------------------------------------
+// Main driver of UTFConversion specialized for different Src encodings.
+// dest has to have enough room for the converted text.
+
+template <typename DestChar>
+bool DoUTFConversion(const char* src,
+                     int32_t src_len,
+                     DestChar* dest,
+                     int32_t* dest_len) {
+  bool success = true;
+
+  for (int32_t i = 0; i < src_len;) {
+    int32_t code_point;
+    CBU8_NEXT(src, i, src_len, code_point);
+
+    if (!IsValidCodepoint(code_point)) {
+      success = false;
+      code_point = kErrorCodePoint;
+    }
+
+    UnicodeAppendUnsafe(dest, dest_len, code_point);
+  }
+
+  return success;
+}
+
+template <typename DestChar>
+bool DoUTFConversion(const char16* src,
+                     int32_t src_len,
+                     DestChar* dest,
+                     int32_t* dest_len) {
+  bool success = true;
+
+  auto ConvertSingleChar = [&success](char16 in) -> int32_t {
+    if (!CBU16_IS_SINGLE(in) || !IsValidCodepoint(in)) {
+      success = false;
+      return kErrorCodePoint;
+    }
+    return in;
+  };
+
+  int32_t i = 0;
+
+  // Always have another symbol in order to avoid checking boundaries in the
+  // middle of the surrogate pair.
+  while (i < src_len - 1) {
+    int32_t code_point;
+
+    if (CBU16_IS_LEAD(src[i]) && CBU16_IS_TRAIL(src[i + 1])) {
+      code_point = CBU16_GET_SUPPLEMENTARY(src[i], src[i + 1]);
+      if (!IsValidCodepoint(code_point)) {
+        code_point = kErrorCodePoint;
+        success = false;
+      }
+      i += 2;
+    } else {
+      code_point = ConvertSingleChar(src[i]);
+      ++i;
+    }
+
+    UnicodeAppendUnsafe(dest, dest_len, code_point);
+  }
+
+  if (i < src_len)
+    UnicodeAppendUnsafe(dest, dest_len, ConvertSingleChar(src[i]));
+
+  return success;
+}
+
+#if defined(WCHAR_T_IS_UTF32)
+
+template <typename DestChar>
+bool DoUTFConversion(const wchar_t* src,
+                     int32_t src_len,
+                     DestChar* dest,
+                     int32_t* dest_len) {
+  bool success = true;
+
+  for (int32_t i = 0; i < src_len; ++i) {
+    int32_t code_point = src[i];
+
+    if (!IsValidCodepoint(code_point)) {
+      success = false;
+      code_point = kErrorCodePoint;
+    }
+
+    UnicodeAppendUnsafe(dest, dest_len, code_point);
+  }
+
+  return success;
+}
+
+#endif  // defined(WCHAR_T_IS_UTF32)
+
+// UTFConversion --------------------------------------------------------------
+// Function template for generating all UTF conversions.
+
+template <typename InputString, typename DestString>
+bool UTFConversion(const InputString& src_str, DestString* dest_str) {
+  if (IsStringASCII(src_str)) {
+    dest_str->assign(src_str.begin(), src_str.end());
+    return true;
+  }
+
+  dest_str->resize(src_str.length() *
+                   size_coefficient_v<typename InputString::value_type,
+                                      typename DestString::value_type>);
+
+  // Empty string is ASCII => it OK to call operator[].
+  auto* dest = &(*dest_str)[0];
+
+  // ICU requires 32 bit numbers.
+  int32_t src_len32 = static_cast<int32_t>(src_str.length());
+  int32_t dest_len32 = 0;
+
+  bool res = DoUTFConversion(src_str.data(), src_len32, dest, &dest_len32);
+
+  dest_str->resize(dest_len32);
+  dest_str->shrink_to_fit();
+
+  return res;
+}
+
+}  // namespace
+
+// UTF16 <-> UTF8 --------------------------------------------------------------
+
+bool UTF8ToUTF16(const char* src, size_t src_len, string16* output) {
+  return UTFConversion(StringPiece(src, src_len), output);
+}
+
+string16 UTF8ToUTF16(StringPiece utf8) {
+  string16 ret;
+  // Ignore the success flag of this call, it will do the best it can for
+  // invalid input, which is what we want here.
+  UTF8ToUTF16(utf8.data(), utf8.size(), &ret);
+  return ret;
+}
+
+bool UTF16ToUTF8(const char16* src, size_t src_len, std::string* output) {
+  return UTFConversion(StringPiece16(src, src_len), output);
+}
+
+std::string UTF16ToUTF8(StringPiece16 utf16) {
+  std::string ret;
+  // Ignore the success flag of this call, it will do the best it can for
+  // invalid input, which is what we want here.
+  UTF16ToUTF8(utf16.data(), utf16.length(), &ret);
+  return ret;
+}
+
+// UTF-16 <-> Wide -------------------------------------------------------------
+
+#if defined(WCHAR_T_IS_UTF16)
+// When wide == UTF-16 the conversions are a NOP.
+
+bool WideToUTF16(const wchar_t* src, size_t src_len, string16* output) {
+  output->assign(src, src + src_len);
+  return true;
+}
+
+string16 WideToUTF16(WStringPiece wide) {
+  return string16(wide.begin(), wide.end());
+}
+
+bool UTF16ToWide(const char16* src, size_t src_len, std::wstring* output) {
+  output->assign(src, src + src_len);
+  return true;
+}
+
+std::wstring UTF16ToWide(StringPiece16 utf16) {
+  return std::wstring(utf16.begin(), utf16.end());
+}
+
+#elif defined(WCHAR_T_IS_UTF32)
+
+bool WideToUTF16(const wchar_t* src, size_t src_len, string16* output) {
+  return UTFConversion(base::WStringPiece(src, src_len), output);
+}
+
+string16 WideToUTF16(WStringPiece wide) {
+  string16 ret;
+  // Ignore the success flag of this call, it will do the best it can for
+  // invalid input, which is what we want here.
+  WideToUTF16(wide.data(), wide.length(), &ret);
+  return ret;
+}
+
+bool UTF16ToWide(const char16* src, size_t src_len, std::wstring* output) {
+  return UTFConversion(StringPiece16(src, src_len), output);
+}
+
+std::wstring UTF16ToWide(StringPiece16 utf16) {
+  std::wstring ret;
+  // Ignore the success flag of this call, it will do the best it can for
+  // invalid input, which is what we want here.
+  UTF16ToWide(utf16.data(), utf16.length(), &ret);
+  return ret;
+}
+
+#endif  // defined(WCHAR_T_IS_UTF32)
+
+// UTF-8 <-> Wide --------------------------------------------------------------
+
+// UTF8ToWide is the same code, regardless of whether wide is 16 or 32 bits
+
+bool UTF8ToWide(const char* src, size_t src_len, std::wstring* output) {
+  return UTFConversion(StringPiece(src, src_len), output);
+}
+
+std::wstring UTF8ToWide(StringPiece utf8) {
+  std::wstring ret;
+  // Ignore the success flag of this call, it will do the best it can for
+  // invalid input, which is what we want here.
+  UTF8ToWide(utf8.data(), utf8.length(), &ret);
+  return ret;
+}
+
+#if defined(WCHAR_T_IS_UTF16)
+// Easy case since we can use the "utf" versions we already wrote above.
+
+bool WideToUTF8(const wchar_t* src, size_t src_len, std::string* output) {
+  return UTF16ToUTF8(as_u16cstr(src), src_len, output);
+}
+
+std::string WideToUTF8(WStringPiece wide) {
+  return UTF16ToUTF8(StringPiece16(as_u16cstr(wide), wide.size()));
+}
+
+#elif defined(WCHAR_T_IS_UTF32)
+
+bool WideToUTF8(const wchar_t* src, size_t src_len, std::string* output) {
+  return UTFConversion(WStringPiece(src, src_len), output);
+}
+
+std::string WideToUTF8(WStringPiece wide) {
+  std::string ret;
+  // Ignore the success flag of this call, it will do the best it can for
+  // invalid input, which is what we want here.
+  WideToUTF8(wide.data(), wide.length(), &ret);
+  return ret;
+}
+
+#endif  // defined(WCHAR_T_IS_UTF32)
+
+string16 ASCIIToUTF16(StringPiece ascii) {
+  DCHECK(IsStringASCII(ascii)) << ascii;
+  return string16(ascii.begin(), ascii.end());
+}
+
+std::string UTF16ToASCII(StringPiece16 utf16) {
+  DCHECK(IsStringASCII(utf16)) << UTF16ToUTF8(utf16);
+  return std::string(utf16.begin(), utf16.end());
+}
+
+}  // namespace base