| // Copyright 2013 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. |
| |
| // ICU-based IDNA converter. |
| |
| #include <stdint.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "base/lazy_instance.h" |
| #include "base/logging.h" |
| #include "third_party/icu/source/common/unicode/uidna.h" |
| #include "third_party/icu/source/common/unicode/utypes.h" |
| #include "url/url_canon_icu.h" |
| #include "url/url_canon_internal.h" // for _itoa_s |
| |
| namespace url { |
| |
| namespace { |
| |
| // A wrapper to use LazyInstance<>::Leaky with ICU's UIDNA, a C pointer to |
| // a UTS46/IDNA 2008 handling object opened with uidna_openUTS46(). |
| // |
| // We use UTS46 with BiDiCheck to migrate from IDNA 2003 (with unassigned |
| // code points allowed) to IDNA 2008 with |
| // the backward compatibility in mind. What it does: |
| // |
| // 1. Use the up-to-date Unicode data. |
| // 2. Define a case folding/mapping with the up-to-date Unicode data as |
| // in IDNA 2003. |
| // 3. Use transitional mechanism for 4 deviation characters (sharp-s, |
| // final sigma, ZWJ and ZWNJ) for now. |
| // 4. Continue to allow symbols and punctuations. |
| // 5. Apply new BiDi check rules more permissive than the IDNA 2003 BiDI rules. |
| // 6. Do not apply STD3 rules |
| // 7. Do not allow unassigned code points. |
| // |
| // It also closely matches what IE 10 does except for the BiDi check ( |
| // http://goo.gl/3XBhqw ). |
| // See http://http://unicode.org/reports/tr46/ and references therein |
| // for more details. |
| struct UIDNAWrapper { |
| UIDNAWrapper() { |
| UErrorCode err = U_ZERO_ERROR; |
| // TODO(jungshik): Change options as different parties (browsers, |
| // registrars, search engines) converge toward a consensus. |
| value = uidna_openUTS46(UIDNA_CHECK_BIDI, &err); |
| if (U_FAILURE(err)) { |
| CHECK(false) << "failed to open UTS46 data with error: " |
| << u_errorName(err) |
| << ". If you see this error message in a test environment " |
| << "your test environment likely lacks the required data " |
| << "tables for libicu. See https://crbug.com/778929."; |
| value = NULL; |
| } |
| } |
| |
| UIDNA* value; |
| }; |
| |
| } // namespace |
| |
| static base::LazyInstance<UIDNAWrapper>::Leaky g_uidna = |
| LAZY_INSTANCE_INITIALIZER; |
| |
| // Converts the Unicode input representing a hostname to ASCII using IDN rules. |
| // The output must be ASCII, but is represented as wide characters. |
| // |
| // On success, the output will be filled with the ASCII host name and it will |
| // return true. Unlike most other canonicalization functions, this assumes that |
| // the output is empty. The beginning of the host will be at offset 0, and |
| // the length of the output will be set to the length of the new host name. |
| // |
| // On error, this will return false. The output in this case is undefined. |
| // TODO(jungshik): use UTF-8/ASCII version of nameToASCII. |
| // Change the function signature and callers accordingly to avoid unnecessary |
| // conversions in our code. In addition, consider using icu::IDNA's UTF-8/ASCII |
| // version with StringByteSink. That way, we can avoid C wrappers and additional |
| // string conversion. |
| bool IDNToASCII(const base::char16* src, int src_len, CanonOutputW* output) { |
| DCHECK(output->length() == 0); // Output buffer is assumed empty. |
| |
| UIDNA* uidna = g_uidna.Get().value; |
| DCHECK(uidna != NULL); |
| while (true) { |
| UErrorCode err = U_ZERO_ERROR; |
| UIDNAInfo info = UIDNA_INFO_INITIALIZER; |
| int output_length = uidna_nameToASCII(uidna, src, src_len, output->data(), |
| output->capacity(), &info, &err); |
| if (U_SUCCESS(err) && info.errors == 0) { |
| output->set_length(output_length); |
| return true; |
| } |
| |
| // TODO(jungshik): Look at info.errors to handle them case-by-case basis |
| // if necessary. |
| if (err != U_BUFFER_OVERFLOW_ERROR || info.errors != 0) |
| return false; // Unknown error, give up. |
| |
| // Not enough room in our buffer, expand. |
| output->Resize(output_length); |
| } |
| } |
| |
| } // namespace url |