blob: 06fc15edd3668e367d0551cf4314de04beb73c65 [file] [log] [blame]
// Copyright (c) 2012 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.
// The rules for parsing content-types were borrowed from Firefox:
// http://lxr.mozilla.org/mozilla/source/netwerk/base/src/nsURLHelper.cpp#834
#include "net/http/http_util.h"
#include <algorithm>
#include "base/logging.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_piece.h"
#include "base/strings/string_tokenizer.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/time/time.h"
#include "net/base/url_util.h"
namespace net {
// Helpers --------------------------------------------------------------------
// Returns the index of the closing quote of the string, if any. |start| points
// at the opening quote.
static size_t FindStringEnd(const std::string& line, size_t start, char delim) {
DCHECK_LT(start, line.length());
DCHECK_EQ(line[start], delim);
DCHECK((delim == '"') || (delim == '\''));
const char set[] = { delim, '\\', '\0' };
for (size_t end = line.find_first_of(set, start + 1);
end != std::string::npos; end = line.find_first_of(set, end + 2)) {
if (line[end] != '\\')
return end;
}
return line.length();
}
// HttpUtil -------------------------------------------------------------------
// static
std::string HttpUtil::SpecForRequest(const GURL& url) {
// We may get ftp scheme when fetching ftp resources through proxy.
DCHECK(url.is_valid() && (url.SchemeIsHTTPOrHTTPS() || url.SchemeIs("ftp") ||
url.SchemeIsWSOrWSS()));
return SimplifyUrlForRequest(url).spec();
}
// static
void HttpUtil::ParseContentType(const std::string& content_type_str,
std::string* mime_type,
std::string* charset,
bool* had_charset,
std::string* boundary) {
const std::string::const_iterator begin = content_type_str.begin();
// Trim leading and trailing whitespace from type. We include '(' in
// the trailing trim set to catch media-type comments, which are not at all
// standard, but may occur in rare cases.
size_t type_val = content_type_str.find_first_not_of(HTTP_LWS);
type_val = std::min(type_val, content_type_str.length());
size_t type_end = content_type_str.find_first_of(HTTP_LWS ";(", type_val);
if (type_end == std::string::npos)
type_end = content_type_str.length();
size_t charset_val = 0;
size_t charset_end = 0;
bool type_has_charset = false;
// Iterate over parameters
size_t param_start = content_type_str.find_first_of(';', type_end);
if (param_start != std::string::npos) {
base::StringTokenizer tokenizer(begin + param_start, content_type_str.end(),
";");
tokenizer.set_quote_chars("\"");
while (tokenizer.GetNext()) {
std::string::const_iterator equals_sign =
std::find(tokenizer.token_begin(), tokenizer.token_end(), '=');
if (equals_sign == tokenizer.token_end())
continue;
std::string::const_iterator param_name_begin = tokenizer.token_begin();
std::string::const_iterator param_name_end = equals_sign;
TrimLWS(&param_name_begin, &param_name_end);
std::string::const_iterator param_value_begin = equals_sign + 1;
std::string::const_iterator param_value_end = tokenizer.token_end();
DCHECK(param_value_begin <= tokenizer.token_end());
TrimLWS(&param_value_begin, &param_value_end);
if (base::LowerCaseEqualsASCII(
base::StringPiece(param_name_begin, param_name_end), "charset")) {
// TODO(abarth): Refactor this function to consistently use iterators.
charset_val = param_value_begin - begin;
charset_end = param_value_end - begin;
type_has_charset = true;
} else if (base::LowerCaseEqualsASCII(
base::StringPiece(param_name_begin, param_name_end),
"boundary")) {
if (boundary)
boundary->assign(param_value_begin, param_value_end);
}
}
}
if (type_has_charset) {
// Trim leading and trailing whitespace from charset_val. We include
// '(' in the trailing trim set to catch media-type comments, which are
// not at all standard, but may occur in rare cases.
charset_val = content_type_str.find_first_not_of(HTTP_LWS, charset_val);
charset_val = std::min(charset_val, charset_end);
char first_char = content_type_str[charset_val];
if (first_char == '"' || first_char == '\'') {
charset_end = FindStringEnd(content_type_str, charset_val, first_char);
++charset_val;
DCHECK(charset_end >= charset_val);
} else {
charset_end = std::min(content_type_str.find_first_of(HTTP_LWS ";(",
charset_val),
charset_end);
}
}
// if the server sent "*/*", it is meaningless, so do not store it.
// also, if type_val is the same as mime_type, then just update the
// charset. however, if charset is empty and mime_type hasn't
// changed, then don't wipe-out an existing charset. We
// also want to reject a mime-type if it does not include a slash.
// some servers give junk after the charset parameter, which may
// include a comma, so this check makes us a bit more tolerant.
if (content_type_str.length() != 0 &&
content_type_str != "*/*" &&
content_type_str.find_first_of('/') != std::string::npos) {
// Common case here is that mime_type is empty
bool eq = !mime_type->empty() &&
base::LowerCaseEqualsASCII(
base::StringPiece(begin + type_val, begin + type_end),
mime_type->data());
if (!eq) {
*mime_type = base::ToLowerASCII(
base::StringPiece(begin + type_val, begin + type_end));
}
if ((!eq && *had_charset) || type_has_charset) {
*had_charset = true;
*charset = base::ToLowerASCII(
base::StringPiece(begin + charset_val, begin + charset_end));
}
}
}
// static
// Parse the Range header according to RFC 2616 14.35.1
// ranges-specifier = byte-ranges-specifier
// byte-ranges-specifier = bytes-unit "=" byte-range-set
// byte-range-set = 1#( byte-range-spec | suffix-byte-range-spec )
// byte-range-spec = first-byte-pos "-" [last-byte-pos]
// first-byte-pos = 1*DIGIT
// last-byte-pos = 1*DIGIT
bool HttpUtil::ParseRanges(const std::string& headers,
std::vector<HttpByteRange>* ranges) {
std::string ranges_specifier;
HttpUtil::HeadersIterator it(headers.begin(), headers.end(), "\r\n");
while (it.GetNext()) {
// Look for "Range" header.
if (!base::LowerCaseEqualsASCII(it.name(), "range"))
continue;
ranges_specifier = it.values();
// We just care about the first "Range" header, so break here.
break;
}
if (ranges_specifier.empty())
return false;
return ParseRangeHeader(ranges_specifier, ranges);
}
// static
bool HttpUtil::ParseRangeHeader(const std::string& ranges_specifier,
std::vector<HttpByteRange>* ranges) {
size_t equal_char_offset = ranges_specifier.find('=');
if (equal_char_offset == std::string::npos)
return false;
// Try to extract bytes-unit part.
std::string::const_iterator bytes_unit_begin = ranges_specifier.begin();
std::string::const_iterator bytes_unit_end = bytes_unit_begin +
equal_char_offset;
std::string::const_iterator byte_range_set_begin = bytes_unit_end + 1;
std::string::const_iterator byte_range_set_end = ranges_specifier.end();
TrimLWS(&bytes_unit_begin, &bytes_unit_end);
// "bytes" unit identifier is not found.
if (!base::LowerCaseEqualsASCII(
base::StringPiece(bytes_unit_begin, bytes_unit_end), "bytes"))
return false;
ValuesIterator byte_range_set_iterator(byte_range_set_begin,
byte_range_set_end, ',');
while (byte_range_set_iterator.GetNext()) {
size_t minus_char_offset = byte_range_set_iterator.value().find('-');
// If '-' character is not found, reports failure.
if (minus_char_offset == std::string::npos)
return false;
std::string::const_iterator first_byte_pos_begin =
byte_range_set_iterator.value_begin();
std::string::const_iterator first_byte_pos_end =
first_byte_pos_begin + minus_char_offset;
TrimLWS(&first_byte_pos_begin, &first_byte_pos_end);
std::string first_byte_pos(first_byte_pos_begin, first_byte_pos_end);
HttpByteRange range;
// Try to obtain first-byte-pos.
if (!first_byte_pos.empty()) {
int64_t first_byte_position = -1;
if (!base::StringToInt64(first_byte_pos, &first_byte_position))
return false;
range.set_first_byte_position(first_byte_position);
}
std::string::const_iterator last_byte_pos_begin =
byte_range_set_iterator.value_begin() + minus_char_offset + 1;
std::string::const_iterator last_byte_pos_end =
byte_range_set_iterator.value_end();
TrimLWS(&last_byte_pos_begin, &last_byte_pos_end);
std::string last_byte_pos(last_byte_pos_begin, last_byte_pos_end);
// We have last-byte-pos or suffix-byte-range-spec in this case.
if (!last_byte_pos.empty()) {
int64_t last_byte_position;
if (!base::StringToInt64(last_byte_pos, &last_byte_position))
return false;
if (range.HasFirstBytePosition())
range.set_last_byte_position(last_byte_position);
else
range.set_suffix_length(last_byte_position);
} else if (!range.HasFirstBytePosition()) {
return false;
}
// Do a final check on the HttpByteRange object.
if (!range.IsValid())
return false;
ranges->push_back(range);
}
return !ranges->empty();
}
// static
bool HttpUtil::ParseRetryAfterHeader(const std::string& retry_after_string,
base::Time now,
base::TimeDelta* retry_after) {
int seconds;
base::Time time;
base::TimeDelta interval;
if (base::StringToInt(retry_after_string, &seconds)) {
interval = base::TimeDelta::FromSeconds(seconds);
} else if (base::Time::FromUTCString(retry_after_string.c_str(), &time)) {
interval = time - now;
} else {
return false;
}
if (interval < base::TimeDelta::FromSeconds(0))
return false;
*retry_after = interval;
return true;
}
// static
bool HttpUtil::HasHeader(const std::string& headers, const char* name) {
size_t name_len = strlen(name);
std::string::const_iterator it =
std::search(headers.begin(),
headers.end(),
name,
name + name_len,
base::CaseInsensitiveCompareASCII<char>());
if (it == headers.end())
return false;
// ensure match is prefixed by newline
if (it != headers.begin() && it[-1] != '\n')
return false;
// ensure match is suffixed by colon
if (it + name_len >= headers.end() || it[name_len] != ':')
return false;
return true;
}
namespace {
// A header string containing any of the following fields will cause
// an error. The list comes from the XMLHttpRequest standard.
// http://www.w3.org/TR/XMLHttpRequest/#the-setrequestheader-method
const char* const kForbiddenHeaderFields[] = {
"accept-charset",
"accept-encoding",
"access-control-request-headers",
"access-control-request-method",
"connection",
"content-length",
"cookie",
"cookie2",
"content-transfer-encoding",
"date",
"expect",
"host",
"keep-alive",
"origin",
"referer",
"te",
"trailer",
"transfer-encoding",
"upgrade",
"user-agent",
"via",
};
} // anonymous namespace
// static
bool HttpUtil::IsSafeHeader(const std::string& name) {
std::string lower_name(base::ToLowerASCII(name));
if (base::StartsWith(lower_name, "proxy-", base::CompareCase::SENSITIVE) ||
base::StartsWith(lower_name, "sec-", base::CompareCase::SENSITIVE))
return false;
for (size_t i = 0; i < arraysize(kForbiddenHeaderFields); ++i) {
if (lower_name == kForbiddenHeaderFields[i])
return false;
}
return true;
}
// static
bool HttpUtil::IsValidHeaderName(const std::string& name) {
// Check whether the header name is RFC 2616-compliant.
return HttpUtil::IsToken(name);
}
// static
bool HttpUtil::IsValidHeaderValue(const std::string& value) {
// Just a sanity check: disallow NUL and CRLF.
return value.find('\0') == std::string::npos &&
value.find("\r\n") == std::string::npos;
}
// static
bool HttpUtil::IsValidHeaderValueRFC7230(const base::StringPiece& value) {
// This empty string is a valid header-value.
if (value.empty())
return true;
// Check leading/trailing whitespaces.
if (IsLWS(value[0]) || IsLWS(value[value.size() - 1]))
return false;
// Check each octet is |field-vchar|, |SP| or |HTAB|.
for (unsigned char c : value) {
if (c == 0x7F || (c < 0x20 && c != '\t'))
return false;
}
return true;
}
// static
std::string HttpUtil::StripHeaders(const std::string& headers,
const char* const headers_to_remove[],
size_t headers_to_remove_len) {
std::string stripped_headers;
HttpUtil::HeadersIterator it(headers.begin(), headers.end(), "\r\n");
while (it.GetNext()) {
bool should_remove = false;
for (size_t i = 0; i < headers_to_remove_len; ++i) {
if (base::LowerCaseEqualsASCII(
base::StringPiece(it.name_begin(), it.name_end()),
headers_to_remove[i])) {
should_remove = true;
break;
}
}
if (!should_remove) {
// Assume that name and values are on the same line.
stripped_headers.append(it.name_begin(), it.values_end());
stripped_headers.append("\r\n");
}
}
return stripped_headers;
}
// static
bool HttpUtil::IsNonCoalescingHeader(std::string::const_iterator name_begin,
std::string::const_iterator name_end) {
// NOTE: "set-cookie2" headers do not support expires attributes, so we don't
// have to list them here.
const char* const kNonCoalescingHeaders[] = {
"date",
"expires",
"last-modified",
"location", // See bug 1050541 for details
"retry-after",
"set-cookie",
// The format of auth-challenges mixes both space separated tokens and
// comma separated properties, so coalescing on comma won't work.
"www-authenticate",
"proxy-authenticate",
// STS specifies that UAs must not process any STS headers after the first
// one.
"strict-transport-security"
};
for (size_t i = 0; i < arraysize(kNonCoalescingHeaders); ++i) {
if (base::LowerCaseEqualsASCII(base::StringPiece(name_begin, name_end),
kNonCoalescingHeaders[i]))
return true;
}
return false;
}
bool HttpUtil::IsLWS(char c) {
return strchr(HTTP_LWS, c) != NULL;
}
void HttpUtil::TrimLWS(std::string::const_iterator* begin,
std::string::const_iterator* end) {
// leading whitespace
while (*begin < *end && IsLWS((*begin)[0]))
++(*begin);
// trailing whitespace
while (*begin < *end && IsLWS((*end)[-1]))
--(*end);
}
bool HttpUtil::IsQuote(char c) {
// Single quote mark isn't actually part of quoted-text production,
// but apparently some servers rely on this.
return c == '"' || c == '\'';
}
namespace {
bool IsTokenChar(unsigned char c) {
return !(c >= 0x80 || c <= 0x1F || c == 0x7F || c == '(' || c == ')' ||
c == '<' || c == '>' || c == '@' || c == ',' || c == ';' ||
c == ':' || c == '\\' || c == '"' || c == '/' || c == '[' ||
c == ']' || c == '?' || c == '=' || c == '{' || c == '}' ||
c == ' ' || c == '\t');
}
} // anonymous namespace
// See RFC 2616 Sec 2.2 for the definition of |token|.
bool HttpUtil::IsToken(std::string::const_iterator begin,
std::string::const_iterator end) {
if (begin == end)
return false;
for (std::string::const_iterator iter = begin; iter != end; ++iter) {
if (!IsTokenChar(*iter))
return false;
}
return true;
}
// See RFC 5987 Sec 3.2.1 for the definition of |parmname|.
bool HttpUtil::IsParmName(std::string::const_iterator begin,
std::string::const_iterator end) {
if (begin == end)
return false;
for (std::string::const_iterator iter = begin; iter != end; ++iter) {
unsigned char c = *iter;
if (!IsTokenChar(c) || c == '*' || c == '\'' || c == '%')
return false;
}
return true;
}
namespace {
bool UnquoteImpl(std::string::const_iterator begin,
std::string::const_iterator end,
bool strict_quotes,
std::string* out) {
// Empty string
if (begin == end)
return false;
// Nothing to unquote.
if (!HttpUtil::IsQuote(*begin))
return false;
// Anything other than double quotes in strict mode.
if (strict_quotes && *begin != '"')
return false;
// No terminal quote mark.
if (end - begin < 2 || *begin != *(end - 1))
return false;
char quote = *begin;
// Strip quotemarks
++begin;
--end;
// Unescape quoted-pair (defined in RFC 2616 section 2.2)
bool prev_escape = false;
std::string unescaped;
for (; begin != end; ++begin) {
char c = *begin;
if (c == '\\' && !prev_escape) {
prev_escape = true;
continue;
}
if (strict_quotes && !prev_escape && c == quote)
return false;
prev_escape = false;
unescaped.push_back(c);
}
// Terminal quote is escaped.
if (strict_quotes && prev_escape)
return false;
*out = std::move(unescaped);
return true;
}
} // anonymous namespace
std::string HttpUtil::Unquote(std::string::const_iterator begin,
std::string::const_iterator end) {
std::string result;
if (!UnquoteImpl(begin, end, false, &result))
return std::string(begin, end);
return result;
}
// static
std::string HttpUtil::Unquote(const std::string& str) {
return Unquote(str.begin(), str.end());
}
// static
bool HttpUtil::StrictUnquote(std::string::const_iterator begin,
std::string::const_iterator end,
std::string* out) {
return UnquoteImpl(begin, end, true, out);
}
// static
bool HttpUtil::StrictUnquote(const std::string& str, std::string* out) {
return StrictUnquote(str.begin(), str.end(), out);
}
// static
std::string HttpUtil::Quote(const std::string& str) {
std::string escaped;
escaped.reserve(2 + str.size());
std::string::const_iterator begin = str.begin();
std::string::const_iterator end = str.end();
// Esape any backslashes or quotemarks within the string, and
// then surround with quotes.
escaped.push_back('"');
for (; begin != end; ++begin) {
char c = *begin;
if (c == '"' || c == '\\')
escaped.push_back('\\');
escaped.push_back(c);
}
escaped.push_back('"');
return escaped;
}
// Find the "http" substring in a status line. This allows for
// some slop at the start. If the "http" string could not be found
// then returns -1.
// static
int HttpUtil::LocateStartOfStatusLine(const char* buf, int buf_len) {
const int slop = 4;
const int http_len = 4;
if (buf_len >= http_len) {
int i_max = std::min(buf_len - http_len, slop);
for (int i = 0; i <= i_max; ++i) {
if (base::LowerCaseEqualsASCII(base::StringPiece(buf + i, http_len),
"http"))
return i;
}
}
return -1; // Not found
}
static int LocateEndOfHeadersHelper(const char* buf,
int buf_len,
int i,
bool accept_empty_header_list) {
char last_c = '\0';
bool was_lf = false;
if (accept_empty_header_list) {
// Normally two line breaks signal the end of a header list. An empty header
// list ends with a single line break at the start of the buffer.
last_c = '\n';
was_lf = true;
}
for (; i < buf_len; ++i) {
char c = buf[i];
if (c == '\n') {
if (was_lf)
return i + 1;
was_lf = true;
} else if (c != '\r' || last_c != '\n') {
was_lf = false;
}
last_c = c;
}
return -1;
}
int HttpUtil::LocateEndOfAdditionalHeaders(const char* buf,
int buf_len,
int i) {
return LocateEndOfHeadersHelper(buf, buf_len, i, true);
}
int HttpUtil::LocateEndOfHeaders(const char* buf, int buf_len, int i) {
return LocateEndOfHeadersHelper(buf, buf_len, i, false);
}
// In order for a line to be continuable, it must specify a
// non-blank header-name. Line continuations are specifically for
// header values -- do not allow headers names to span lines.
static bool IsLineSegmentContinuable(const char* begin, const char* end) {
if (begin == end)
return false;
const char* colon = std::find(begin, end, ':');
if (colon == end)
return false;
const char* name_begin = begin;
const char* name_end = colon;
// Name can't be empty.
if (name_begin == name_end)
return false;
// Can't start with LWS (this would imply the segment is a continuation)
if (HttpUtil::IsLWS(*name_begin))
return false;
return true;
}
// Helper used by AssembleRawHeaders, to find the end of the status line.
static const char* FindStatusLineEnd(const char* begin, const char* end) {
size_t i = base::StringPiece(begin, end - begin).find_first_of("\r\n");
if (i == base::StringPiece::npos)
return end;
return begin + i;
}
// Helper used by AssembleRawHeaders, to skip past leading LWS.
static const char* FindFirstNonLWS(const char* begin, const char* end) {
for (const char* cur = begin; cur != end; ++cur) {
if (!HttpUtil::IsLWS(*cur))
return cur;
}
return end; // Not found.
}
std::string HttpUtil::AssembleRawHeaders(const char* input_begin,
int input_len) {
std::string raw_headers;
raw_headers.reserve(input_len);
const char* input_end = input_begin + input_len;
// Skip any leading slop, since the consumers of this output
// (HttpResponseHeaders) don't deal with it.
int status_begin_offset = LocateStartOfStatusLine(input_begin, input_len);
if (status_begin_offset != -1)
input_begin += status_begin_offset;
// Copy the status line.
const char* status_line_end = FindStatusLineEnd(input_begin, input_end);
raw_headers.append(input_begin, status_line_end);
// After the status line, every subsequent line is a header line segment.
// Should a segment start with LWS, it is a continuation of the previous
// line's field-value.
// TODO(ericroman): is this too permissive? (delimits on [\r\n]+)
base::CStringTokenizer lines(status_line_end, input_end, "\r\n");
// This variable is true when the previous line was continuable.
bool prev_line_continuable = false;
while (lines.GetNext()) {
const char* line_begin = lines.token_begin();
const char* line_end = lines.token_end();
if (prev_line_continuable && IsLWS(*line_begin)) {
// Join continuation; reduce the leading LWS to a single SP.
raw_headers.push_back(' ');
raw_headers.append(FindFirstNonLWS(line_begin, line_end), line_end);
} else {
// Terminate the previous line.
raw_headers.push_back('\n');
// Copy the raw data to output.
raw_headers.append(line_begin, line_end);
// Check if the current line can be continued.
prev_line_continuable = IsLineSegmentContinuable(line_begin, line_end);
}
}
raw_headers.append("\n\n", 2);
// Use '\0' as the canonical line terminator. If the input already contained
// any embeded '\0' characters we will strip them first to avoid interpreting
// them as line breaks.
raw_headers.erase(std::remove(raw_headers.begin(), raw_headers.end(), '\0'),
raw_headers.end());
std::replace(raw_headers.begin(), raw_headers.end(), '\n', '\0');
return raw_headers;
}
std::string HttpUtil::ConvertHeadersBackToHTTPResponse(const std::string& str) {
std::string disassembled_headers;
base::StringTokenizer tokenizer(str, std::string(1, '\0'));
while (tokenizer.GetNext()) {
disassembled_headers.append(tokenizer.token_begin(), tokenizer.token_end());
disassembled_headers.append("\r\n");
}
disassembled_headers.append("\r\n");
return disassembled_headers;
}
// TODO(jungshik): 1. If the list is 'fr-CA,fr-FR,en,de', we have to add
// 'fr' after 'fr-CA' with the same q-value as 'fr-CA' because
// web servers, in general, do not fall back to 'fr' and may end up picking
// 'en' which has a lower preference than 'fr-CA' and 'fr-FR'.
// 2. This function assumes that the input is a comma separated list
// without any whitespace. As long as it comes from the preference and
// a user does not manually edit the preference file, it's the case. Still,
// we may have to make it more robust.
std::string HttpUtil::GenerateAcceptLanguageHeader(
const std::string& raw_language_list) {
// We use integers for qvalue and qvalue decrement that are 10 times
// larger than actual values to avoid a problem with comparing
// two floating point numbers.
const unsigned int kQvalueDecrement10 = 2;
unsigned int qvalue10 = 10;
base::StringTokenizer t(raw_language_list, ",");
std::string lang_list_with_q;
while (t.GetNext()) {
std::string language = t.token();
if (qvalue10 == 10) {
// q=1.0 is implicit.
lang_list_with_q = language;
} else {
DCHECK_LT(qvalue10, 10U);
base::StringAppendF(&lang_list_with_q, ",%s;q=0.%d", language.c_str(),
qvalue10);
}
// It does not make sense to have 'q=0'.
if (qvalue10 > kQvalueDecrement10)
qvalue10 -= kQvalueDecrement10;
}
return lang_list_with_q;
}
void HttpUtil::AppendHeaderIfMissing(const char* header_name,
const std::string& header_value,
std::string* headers) {
if (header_value.empty())
return;
if (HttpUtil::HasHeader(*headers, header_name))
return;
*headers += std::string(header_name) + ": " + header_value + "\r\n";
}
bool HttpUtil::HasStrongValidators(HttpVersion version,
const std::string& etag_header,
const std::string& last_modified_header,
const std::string& date_header) {
if (!HasValidators(version, etag_header, last_modified_header))
return false;
if (version < HttpVersion(1, 1))
return false;
if (!etag_header.empty()) {
size_t slash = etag_header.find('/');
if (slash == std::string::npos || slash == 0)
return true;
std::string::const_iterator i = etag_header.begin();
std::string::const_iterator j = etag_header.begin() + slash;
TrimLWS(&i, &j);
if (!base::LowerCaseEqualsASCII(base::StringPiece(i, j), "w"))
return true;
}
base::Time last_modified;
if (!base::Time::FromString(last_modified_header.c_str(), &last_modified))
return false;
base::Time date;
if (!base::Time::FromString(date_header.c_str(), &date))
return false;
// Last-Modified is implicitly weak unless it is at least 60 seconds before
// the Date value.
return ((date - last_modified).InSeconds() >= 60);
}
bool HttpUtil::HasValidators(HttpVersion version,
const std::string& etag_header,
const std::string& last_modified_header) {
if (version < HttpVersion(1, 0))
return false;
base::Time last_modified;
if (base::Time::FromString(last_modified_header.c_str(), &last_modified))
return true;
// It is OK to consider an empty string in etag_header to be a missing header
// since valid ETags are always quoted-strings (see RFC 2616 3.11) and thus
// empty ETags aren't empty strings (i.e., an empty ETag might be "\"\"").
return version >= HttpVersion(1, 1) && !etag_header.empty();
}
// Functions for histogram initialization. The code 0 is put in the map to
// track status codes that are invalid.
// TODO(gavinp): Greatly prune the collected codes once we learn which
// ones are not sent in practice, to reduce upload size & memory use.
enum {
HISTOGRAM_MIN_HTTP_STATUS_CODE = 100,
HISTOGRAM_MAX_HTTP_STATUS_CODE = 599,
};
// static
std::vector<int> HttpUtil::GetStatusCodesForHistogram() {
std::vector<int> codes;
codes.reserve(
HISTOGRAM_MAX_HTTP_STATUS_CODE - HISTOGRAM_MIN_HTTP_STATUS_CODE + 2);
codes.push_back(0);
for (int i = HISTOGRAM_MIN_HTTP_STATUS_CODE;
i <= HISTOGRAM_MAX_HTTP_STATUS_CODE; ++i)
codes.push_back(i);
return codes;
}
// static
int HttpUtil::MapStatusCodeForHistogram(int code) {
if (HISTOGRAM_MIN_HTTP_STATUS_CODE <= code &&
code <= HISTOGRAM_MAX_HTTP_STATUS_CODE)
return code;
return 0;
}
// BNF from section 4.2 of RFC 2616:
//
// message-header = field-name ":" [ field-value ]
// field-name = token
// field-value = *( field-content | LWS )
// field-content = <the OCTETs making up the field-value
// and consisting of either *TEXT or combinations
// of token, separators, and quoted-string>
//
HttpUtil::HeadersIterator::HeadersIterator(
std::string::const_iterator headers_begin,
std::string::const_iterator headers_end,
const std::string& line_delimiter)
: lines_(headers_begin, headers_end, line_delimiter) {
}
HttpUtil::HeadersIterator::~HeadersIterator() {
}
bool HttpUtil::HeadersIterator::GetNext() {
while (lines_.GetNext()) {
name_begin_ = lines_.token_begin();
values_end_ = lines_.token_end();
std::string::const_iterator colon(std::find(name_begin_, values_end_, ':'));
if (colon == values_end_)
continue; // skip malformed header
name_end_ = colon;
// If the name starts with LWS, it is an invalid line.
// Leading LWS implies a line continuation, and these should have
// already been joined by AssembleRawHeaders().
if (name_begin_ == name_end_ || IsLWS(*name_begin_))
continue;
TrimLWS(&name_begin_, &name_end_);
if (name_begin_ == name_end_)
continue; // skip malformed header
values_begin_ = colon + 1;
TrimLWS(&values_begin_, &values_end_);
// if we got a header name, then we are done.
return true;
}
return false;
}
bool HttpUtil::HeadersIterator::AdvanceTo(const char* name) {
DCHECK(name != NULL);
DCHECK_EQ(0, base::ToLowerASCII(name).compare(name))
<< "the header name must be in all lower case";
while (GetNext()) {
if (base::LowerCaseEqualsASCII(base::StringPiece(name_begin_, name_end_),
name)) {
return true;
}
}
return false;
}
HttpUtil::ValuesIterator::ValuesIterator(
std::string::const_iterator values_begin,
std::string::const_iterator values_end,
char delimiter)
: values_(values_begin, values_end, std::string(1, delimiter)) {
values_.set_quote_chars("\'\"");
}
HttpUtil::ValuesIterator::ValuesIterator(const ValuesIterator& other) = default;
HttpUtil::ValuesIterator::~ValuesIterator() {
}
bool HttpUtil::ValuesIterator::GetNext() {
while (values_.GetNext()) {
value_begin_ = values_.token_begin();
value_end_ = values_.token_end();
TrimLWS(&value_begin_, &value_end_);
// bypass empty values.
if (value_begin_ != value_end_)
return true;
}
return false;
}
HttpUtil::NameValuePairsIterator::NameValuePairsIterator(
std::string::const_iterator begin,
std::string::const_iterator end,
char delimiter,
Values optional_values,
Quotes strict_quotes)
: props_(begin, end, delimiter),
valid_(true),
name_begin_(end),
name_end_(end),
value_begin_(end),
value_end_(end),
value_is_quoted_(false),
values_optional_(optional_values == Values::NOT_REQUIRED),
strict_quotes_(strict_quotes == Quotes::STRICT_QUOTES) {
if (strict_quotes_)
props_.set_quote_chars("\"");
}
HttpUtil::NameValuePairsIterator::NameValuePairsIterator(
std::string::const_iterator begin,
std::string::const_iterator end,
char delimiter)
: NameValuePairsIterator(begin,
end,
delimiter,
Values::REQUIRED,
Quotes::NOT_STRICT) {}
HttpUtil::NameValuePairsIterator::NameValuePairsIterator(
const NameValuePairsIterator& other) = default;
HttpUtil::NameValuePairsIterator::~NameValuePairsIterator() {}
// We expect properties to be formatted as one of:
// name="value"
// name='value'
// name='\'value\''
// name=value
// name = value
// name (if values_optional_ is true)
// Due to buggy implementations found in some embedded devices, we also
// accept values with missing close quotemark (http://crbug.com/39836):
// name="value
bool HttpUtil::NameValuePairsIterator::GetNext() {
if (!props_.GetNext())
return false;
// Set the value as everything. Next we will split out the name.
value_begin_ = props_.value_begin();
value_end_ = props_.value_end();
name_begin_ = name_end_ = value_end_;
// Scan for the equals sign.
std::string::const_iterator equals = std::find(value_begin_, value_end_, '=');
if (equals == value_begin_)
return valid_ = false; // Malformed, no name
if (equals == value_end_ && !values_optional_)
return valid_ = false; // Malformed, no equals sign and values are required
// If an equals sign was found, verify that it wasn't inside of quote marks.
if (equals != value_end_) {
for (std::string::const_iterator it = value_begin_; it != equals; ++it) {
if (IsQuote(*it))
return valid_ = false; // Malformed, quote appears before equals sign
}
}
name_begin_ = value_begin_;
name_end_ = equals;
value_begin_ = (equals == value_end_) ? value_end_ : equals + 1;
TrimLWS(&name_begin_, &name_end_);
TrimLWS(&value_begin_, &value_end_);
value_is_quoted_ = false;
unquoted_value_.clear();
if (equals != value_end_ && value_begin_ == value_end_) {
// Malformed; value is empty
return valid_ = false;
}
if (value_begin_ != value_end_ && IsQuote(*value_begin_)) {
value_is_quoted_ = true;
if (strict_quotes_) {
if (!HttpUtil::StrictUnquote(value_begin_, value_end_, &unquoted_value_))
return valid_ = false;
return true;
}
// Trim surrounding quotemarks off the value
if (*value_begin_ != *(value_end_ - 1) || value_begin_ + 1 == value_end_) {
// NOTE: This is not as graceful as it sounds:
// * quoted-pairs will no longer be unquoted
// (["\"hello] should give ["hello]).
// * Does not detect when the final quote is escaped
// (["value\"] should give [value"])
value_is_quoted_ = false;
++value_begin_; // Gracefully recover from mismatching quotes.
} else {
// Do not store iterators into this. See declaration of unquoted_value_.
unquoted_value_ = HttpUtil::Unquote(value_begin_, value_end_);
}
}
return true;
}
bool HttpUtil::NameValuePairsIterator::IsQuote(char c) const {
if (strict_quotes_)
return c == '"';
return HttpUtil::IsQuote(c);
}
} // namespace net