Fixed bug #1096610: non-integral number of chars in RFC-2047 encoded words.

This commit is contained in:
Vincent Richard 2006-10-02 13:44:00 +00:00
parent 4927c22948
commit b79a6ad890
6 changed files with 450 additions and 118 deletions

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@ -2,6 +2,12 @@
VERSION 0.8.1cvs
================
2006-10-02 Vincent Richard <vincent@vincent-richard.net>
* word, wordEncoder: fixed bug #1096610 which caused encoding of a
non-integral number of characters (and then, generation of
incorrectly-formed words) with multi-bytes charsets.
2006-07-13 Vincent Richard <vincent@vincent-richard.net>
* Fixed bugs in MHTML code: 'CID' prefix should not be case-sensitive;

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@ -140,6 +140,7 @@ libvmime_sources = [
'textPart.hpp',
'types.hpp',
'word.cpp', 'word.hpp',
'wordEncoder.cpp', 'wordEncoder.hpp',
'vmime.hpp',
# ============================== Utility =============================
'utility/childProcess.hpp',

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@ -32,6 +32,8 @@
#include "vmime/encoderB64.hpp"
#include "vmime/encoderQP.hpp"
#include "vmime/wordEncoder.hpp"
namespace vmime
{
@ -481,12 +483,11 @@ void word::generate(utility::outputStream& os, const string::size_type maxLineLe
? maxLineLength
: std::min(maxLineLength, static_cast <string::size_type>(76));
// Base64 if more than 60% non-ascii, quoted-printable else (default)
const string::size_type asciiPercent = (m_buffer.length() == 0 ? 100 : (100 * asciiCount) / m_buffer.length());
const string::value_type encoding = (asciiPercent <= 40) ? 'B' : 'Q';
wordEncoder wordEnc(m_buffer, m_charset);
string wordStart("=?" + m_charset.getName() + "?" + encoding + "?");
string wordEnd("?=");
const string wordStart("=?" + m_charset.getName() + "?" +
(wordEnc.getEncoding() == wordEncoder::ENCODING_B64 ? 'B' : 'Q') + "?");
const string wordEnd("?=");
const string::size_type minWordLength = wordStart.length() + wordEnd.length();
const string::size_type maxLineLength2 = (maxLineLength3 < minWordLength + 1)
@ -520,125 +521,40 @@ void word::generate(utility::outputStream& os, const string::size_type maxLineLe
}
// Encode and fold input buffer
string::const_iterator pos = m_buffer.begin();
string::size_type remaining = m_buffer.length();
encoder* theEncoder = NULL;
if (encoding == 'B') theEncoder = new encoderB64;
else theEncoder = new encoderQP;
string qpEncodedBuffer;
if (encoding == 'Q')
{
theEncoder->getProperties()["rfc2047"] = true;
// In the case of Quoted-Printable encoding, we cannot simply encode input
// buffer line by line. So, we encode the whole buffer and we will fold it
// in the next loop...
utility::inputStreamStringAdapter in(m_buffer);
utility::outputStreamStringAdapter out(qpEncodedBuffer);
theEncoder->encode(in, out);
pos = qpEncodedBuffer.begin();
remaining = qpEncodedBuffer.length();
}
#if 1
if (curLineLength != 1 && !isFirstWord)
{
os << " "; // Separate from previous word
++curLineLength;
}
#endif
for ( ; remaining ; )
for (unsigned int i = 0 ; ; ++i)
{
// Start a new encoded word
os << wordStart;
curLineLength += minWordLength;
// Compute the number of encoded chars that will fit on this line
const string::size_type fit = maxLineLength2 - curLineLength;
const string::size_type fit = maxLineLength2 - minWordLength
- (i == 0 ? curLineLength : NEW_LINE_SEQUENCE_LENGTH);
// Base-64 encoding
if (encoding == 'B')
{
// TODO: WARNING! "Any encoded word which encodes a non-integral
// number of characters or octets is incorrectly formed."
// Get the next encoded chunk
const string chunk = wordEnc.getNextChunk(fit);
// Here, we have a formula to compute the maximum number of source
// characters to encode knowing the maximum number of encoded chars
// (with Base64, 3 bytes of input provide 4 bytes of output).
string::size_type count = (fit > 1) ? ((fit - 1) * 3) / 4 : 1;
if (count > remaining) count = remaining;
if (chunk.empty())
break;
utility::inputStreamStringAdapter in
(m_buffer, pos - m_buffer.begin(), pos - m_buffer.begin() + count);
curLineLength += theEncoder->encode(in, os);
pos += count;
remaining -= count;
}
// Quoted-Printable encoding
else
{
// TODO: WARNING! "Any encoded word which encodes a non-integral
// number of characters or octets is incorrectly formed."
// All we have to do here is to take a certain number of character
// (that is less than or equal to "fit") from the QP encoded buffer,
// but we also make sure not to fold a "=XY" encoded char.
const string::const_iterator qpEnd = qpEncodedBuffer.end();
string::const_iterator lastFoldPos = pos;
string::const_iterator p = pos;
string::size_type n = 0;
while (n < fit && p != qpEnd)
{
if (*p == '=')
{
if (n + 3 >= fit)
{
lastFoldPos = p;
break;
}
p += 3;
n += 3;
}
else
{
++p;
++n;
}
}
if (lastFoldPos == pos)
lastFoldPos = p;
os << string(pos, lastFoldPos);
curLineLength += (lastFoldPos - pos) + 1;
pos += n;
remaining -= n;
}
// End of the encoded word
os << wordEnd;
if (remaining)
// Start a new encoded word
if (i != 0)
{
os << NEW_LINE_SEQUENCE;
curLineLength = NEW_LINE_SEQUENCE_LENGTH;
}
}
delete (theEncoder);
os << wordStart;
curLineLength += minWordLength;
os << chunk;
curLineLength += chunk.length();
// End of the encoded word
os << wordEnd;
}
}
if (newLinePos)

290
src/wordEncoder.cpp Normal file
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@ -0,0 +1,290 @@
//
// VMime library (http://www.vmime.org)
// Copyright (C) 2002-2006 Vincent Richard <vincent@vincent-richard.net>
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of
// the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
//
// Linking this library statically or dynamically with other modules is making
// a combined work based on this library. Thus, the terms and conditions of
// the GNU General Public License cover the whole combination.
//
#include "vmime/wordEncoder.hpp"
#include "vmime/exception.hpp"
#include "vmime/charsetConverter.hpp"
#include "vmime/encoderB64.hpp"
#include "vmime/encoderQP.hpp"
#include "vmime/utility/stringUtils.hpp"
namespace vmime
{
wordEncoder::wordEncoder(const string& buffer, const charset& charset, const Encoding encoding)
: m_buffer(buffer), m_pos(0), m_length(buffer.length()), m_charset(charset), m_encoding(encoding)
{
try
{
string utf8Buffer;
vmime::charset::convert
(buffer, utf8Buffer, charset, vmime::charset(charsets::UTF_8));
m_buffer = utf8Buffer;
m_length = utf8Buffer.length();
m_simple = false;
}
catch (exceptions::charset_conv_error&)
{
// Ignore exception.
// We will fall back on simple encoding.
m_simple = true;
}
if (m_encoding == ENCODING_AUTO)
m_encoding = guessBestEncoding(buffer, charset);
if (m_encoding == ENCODING_B64)
{
m_encoder = vmime::create <encoderB64>();
}
else // ENCODING_QP
{
m_encoder = vmime::create <encoderQP>();
m_encoder->getProperties()["rfc2047"] = true;
}
}
static const string::size_type getUTF8CharLength
(const string& buffer, const string::size_type pos, const string::size_type length)
{
// Gives the number of extra bytes in a UTF8 char, given the leading char
static const unsigned char UTF8_EXTRA_BYTES[256] =
{
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5
};
const unsigned char c = buffer[pos];
const unsigned char n = UTF8_EXTRA_BYTES[c];
if (n < length - pos)
return n + 1;
else
return 1;
}
const string wordEncoder::getNextChunk(const string::size_type maxLength)
{
const string::size_type remaining = m_length - m_pos;
if (remaining == 0)
return string();
vmime::string chunk;
vmime::utility::outputStreamStringAdapter chunkStream(chunk);
// Simple encoding
if (m_simple)
{
// WARNING! Simple encoding can encode a non-integral number of
// characters and then may generate incorrectly-formed words!
if (m_encoding == ENCODING_B64)
{
// Here, we have a formula to compute the maximum number of source
// bytes to encode knowing the maximum number of encoded chars. In
// Base64 encoding, 3 bytes of input provide 4 bytes of output.
const string::size_type inputCount =
std::min(remaining, (maxLength > 1) ? ((maxLength - 1) * 3) / 4 : 1);
// Encode chunk
utility::inputStreamStringAdapter in(m_buffer, m_pos, m_pos + inputCount);
m_encoder->encode(in, chunkStream);
m_pos += inputCount;
}
else // ENCODING_QP
{
// Compute exactly how much input bytes are needed to have an output
// string length of less than 'maxLength' bytes. In Quoted-Printable
// encoding, encoded bytes take 3 bytes.
string::size_type inputCount = 0;
string::size_type outputCount = 0;
while ((inputCount == 0 || outputCount < maxLength) && (inputCount < remaining))
{
const unsigned char c = m_buffer[m_pos + inputCount];
bool encoded = true;
switch (c)
{
case ',':
case ';':
case ':':
case '_':
case '=':
encoded = true;
break;
default:
if (c >= 33 && c <= 126 && c != 61)
encoded = false;
break;
}
inputCount++;
outputCount += (encoded ? 3 : 1);
}
// Encode chunk
utility::inputStreamStringAdapter in(m_buffer, m_pos, m_pos + inputCount);
m_encoder->encode(in, chunkStream);
m_pos += inputCount;
}
}
// Fully RFC-compliant encoding
else
{
charsetConverter conv(vmime::charset(charsets::UTF_8), m_charset);
string::size_type inputCount = 0;
string::size_type outputCount = 0;
string encodeBuffer;
while ((inputCount == 0 || outputCount < maxLength) && (inputCount < remaining))
{
// Get the next UTF8 character
const string::size_type inputCharLength =
getUTF8CharLength(m_buffer, m_pos + inputCount, m_length);
const string inputChar(m_buffer.begin() + m_pos + inputCount,
m_buffer.begin() + m_pos + inputCount + inputCharLength);
// Convert back to original encoding
string encodeBytes;
conv.convert(inputChar, encodeBytes);
encodeBuffer += encodeBytes;
// Compute number of output bytes
if (m_encoding == ENCODING_B64)
{
outputCount = std::max(static_cast <string::size_type>(4),
(encodeBytes.length() * 4) / 3);
}
else // ENCODING_QP
{
for (string::size_type i = 0, n = encodeBytes.length() ; i < n ; ++i)
{
const unsigned char c = encodeBytes[i];
bool encoded = true;
switch (c)
{
case ',':
case ';':
case ':':
case '_':
case '=':
encoded = true;
break;
default:
if (c >= 33 && c <= 126 && c != 61)
encoded = false;
break;
}
outputCount += (encoded ? 3 : 1);
}
}
inputCount += inputCharLength;
}
// Encode chunk
utility::inputStreamStringAdapter in(encodeBuffer);
m_encoder->encode(in, chunkStream);
m_pos += inputCount;
}
return chunk;
}
const wordEncoder::Encoding wordEncoder::getEncoding() const
{
return m_encoding;
}
// static
const wordEncoder::Encoding wordEncoder::guessBestEncoding
(const string& buffer, const charset& charset)
{
// If the charset is ISO-8859-x, set to QP encoding
const string cset = utility::stringUtils::toLower(charset.getName());
if (cset.find("iso-8859") != string::npos ||
cset.find("iso8859") != string::npos)
{
return ENCODING_QP;
}
// Use Base64 if more than 40% non-ASCII, or Quoted-Printable else (default)
const string::size_type asciiCount =
utility::stringUtils::countASCIIchars(buffer.begin(), buffer.end());
const string::size_type asciiPercent =
(buffer.length() == 0 ? 100 : (100 * asciiCount) / buffer.length());
if (asciiPercent < 60)
return ENCODING_B64;
else
return ENCODING_QP;
}
} // vmime

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@ -41,9 +41,34 @@ VMIME_TEST_SUITE_BEGIN
VMIME_TEST(testWordConstructors)
VMIME_TEST(testWordParse)
VMIME_TEST(testWordGenerate)
VMIME_TEST(testWordGenerateMultiBytes)
VMIME_TEST_LIST_END
static const vmime::string getDisplayText(const vmime::text& t)
{
vmime::string res;
for (int i = 0 ; i < t.getWordCount() ; ++i)
res += t.getWordAt(i)->getBuffer();
return res;
}
static const vmime::string cleanGeneratedWords(const std::string& str)
{
std::istringstream iss(str);
std::string res;
std::string x;
while (std::getline(iss, x))
res += vmime::utility::stringUtils::trim(x);
return res;
}
void testConstructors()
{
vmime::text t1;
@ -171,16 +196,6 @@ VMIME_TEST_SUITE_BEGIN
// TODO
}
static const vmime::string getDisplayText(const vmime::text& t)
{
vmime::string res;
for (int i = 0 ; i < t.getWordCount() ; ++i)
res += t.getWordAt(i)->getBuffer();
return res;
}
void testDisplayForm()
{
#define DISPLAY_FORM(x) getDisplayText(*vmime::text::decodeAndUnfold(x))
@ -254,5 +269,15 @@ VMIME_TEST_SUITE_BEGIN
vmime::word("\xf1\xf2\xf3\xf4\xf5", vmime::charset("foo")).generate());
}
void testWordGenerateMultiBytes()
{
// Ensure we don't encode a non-integral number of characters
VASSERT_EQ("1", "=?utf-8?Q?aaa?==?utf-8?Q?=C3=A9?==?utf-8?Q?zzz?=",
cleanGeneratedWords(vmime::word("aaa\xc3\xa9zzz", vmime::charset("utf-8")).generate(16)));
VASSERT_EQ("1", "=?utf-8?Q?aaa=C3=A9?==?utf-8?Q?zzz?=",
cleanGeneratedWords(vmime::word("aaa\xc3\xa9zzz", vmime::charset("utf-8")).generate(17)));
}
VMIME_TEST_SUITE_END

94
vmime/wordEncoder.hpp Normal file
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@ -0,0 +1,94 @@
//
// VMime library (http://www.vmime.org)
// Copyright (C) 2002-2006 Vincent Richard <vincent@vincent-richard.net>
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of
// the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
//
// Linking this library statically or dynamically with other modules is making
// a combined work based on this library. Thus, the terms and conditions of
// the GNU General Public License cover the whole combination.
//
#ifndef VMIME_WORDENCODER_HPP_INCLUDED
#define VMIME_WORDENCODER_HPP_INCLUDED
#include "vmime/charset.hpp"
namespace vmime
{
class encoder;
/** Encodes words following RFC-2047.
*/
class wordEncoder
{
public:
/** Available encodings for RFC-2047. */
enum Encoding
{
ENCODING_AUTO,
ENCODING_QP,
ENCODING_B64
};
wordEncoder(const string& buffer, const charset& charset, const Encoding encoding = ENCODING_AUTO);
/** Return the next chunk in the word.
*
* @param maxLength maximal length of the chunk
* @return next chunk, of maximal length 'maxLength' if possible
*/
const string getNextChunk(const string::size_type maxLength);
/** Return the encoding used.
*
* @return encoding
*/
const Encoding getEncoding() const;
private:
static const Encoding guessBestEncoding(const string& buffer, const charset& charset);
void guessBestEncoding();
string m_buffer;
string::size_type m_pos;
string::size_type m_length;
bool m_simple;
charset m_charset;
Encoding m_encoding;
ref <encoder> m_encoder;
};
} // vmime
#endif // VMIME_WORDENCODER_HPP_INCLUDED