url_canon_query.cc | Explore in Territory

// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/350788890): Remove this and spanify to fix the errors.
#pragma allow_unsafe_buffers
#endif

#include "url/url_canon.h"
#include "url/url_canon_internal.h"

// Query canonicalization in IE
// ----------------------------
// IE is very permissive for query parameters specified in links on the page
// (in contrast to links that it constructs itself based on form data). It does
// not unescape any character. It does not reject any escape sequence (be they
// invalid like "%2y" or freaky like %00).
//
// IE only escapes spaces and nothing else. Embedded NULLs, tabs (0x09),
// LF (0x0a), and CR (0x0d) are removed (this probably happens at an earlier
// layer since they are removed from all portions of the URL). All other
// characters are passed unmodified. Invalid UTF-16 sequences are preserved as
// well, with each character in the input being converted to UTF-8. It is the
// server's job to make sense of this invalid query.
//
// Invalid multibyte sequences (for example, invalid UTF-8 on a UTF-8 page)
// are converted to the invalid character and sent as unescaped UTF-8 (0xef,
// 0xbf, 0xbd). This may not be canonicalization, the parser may generate these
// strings before the URL handler ever sees them.
//
// Our query canonicalization
// --------------------------
// We escape all non-ASCII characters and control characters, like Firefox.
// This is more conformant to the URL spec, and there do not seem to be many
// problems relating to Firefox's behavior.
//
// Like IE, we will never unescape (although the application may want to try
// unescaping to present the user with a more understandable URL). We will
// replace all invalid sequences (including invalid UTF-16 sequences, which IE
// doesn't) with the "invalid character," and we will escape it.

namespace url {

namespace {

// Appends the given string to the output, escaping characters that do not
// match the given |type| in SharedCharTypes. This version will accept 8 or 16
// bit characters, but assumes that they have only 7-bit values. It also assumes
// that all UTF-8 values are correct, so doesn't bother checking
template<typename CHAR>
void AppendRaw8BitQueryString(const CHAR* source, int length,
                              CanonOutput* output) { … }

// Runs the converter on the given UTF-8 input. Since the converter expects
// UTF-16, we have to convert first. The converter must be non-NULL.
void RunConverter(const char* spec,
                  const Component& query,
                  CharsetConverter* converter,
                  CanonOutput* output) { … }

// Runs the converter with the given UTF-16 input. We don't have to do
// anything, but this overridden function allows us to use the same code
// for both UTF-8 and UTF-16 input.
void RunConverter(const char16_t* spec,
                  const Component& query,
                  CharsetConverter* converter,
                  CanonOutput* output) { … }

template <typename CHAR, typename UCHAR>
void DoConvertToQueryEncoding(const CHAR* spec,
                              const Component& query,
                              CharsetConverter* converter,
                              CanonOutput* output) { … }

template<typename CHAR, typename UCHAR>
void DoCanonicalizeQuery(const CHAR* spec,
                         const Component& query,
                         CharsetConverter* converter,
                         CanonOutput* output,
                         Component* out_query) { … }

}  // namespace

void CanonicalizeQuery(const char* spec,
                       const Component& query,
                       CharsetConverter* converter,
                       CanonOutput* output,
                       Component* out_query) { … }

void CanonicalizeQuery(const char16_t* spec,
                       const Component& query,
                       CharsetConverter* converter,
                       CanonOutput* output,
                       Component* out_query) { … }

void ConvertUTF16ToQueryEncoding(const char16_t* input,
                                 const Component& query,
                                 CharsetConverter* converter,
                                 CanonOutput* output) { … }

}  // namespace url
chromium/url/url_canon_query.cc
