/*
* Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the Computer Systems
* Engineering Group at Lawrence Berkeley Laboratory.
* 4. Neither the name of the University nor of the Laboratory may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Utilities for message formatting used both by libpcap and rpcapd.
*/
#include <config.h>
#include "ftmacros.h"
#include <stddef.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include "pcap-int.h"
#include "portability.h"
#include "fmtutils.h"
#ifdef _WIN32
#include "charconv.h"
#endif
/*
* Set the encoding.
*/
#ifdef _WIN32
/*
* True if we should use UTF-8.
*/
static int use_utf_8;
void
pcapint_fmt_set_encoding(unsigned int opts)
{
if (opts == PCAP_CHAR_ENC_UTF_8)
use_utf_8 = 1;
}
#else
void
pcapint_fmt_set_encoding(unsigned int opts _U_)
{
/*
* Nothing to do here.
*/
}
#endif
#ifdef _WIN32
/*
* Convert a null-terminated UTF-16LE string to UTF-8, putting it into
* a buffer starting at the specified location and stopping if we go
* past the specified size. This will only put out complete UTF-8
* sequences.
*
* We do this ourselves because Microsoft doesn't offer a "convert and
* stop at a UTF-8 character boundary if we run out of space" routine.
*/
#define IS_LEADING_SURROGATE(c) \
((c) >= 0xd800 && (c) < 0xdc00)
#define IS_TRAILING_SURROGATE(c) \
((c) >= 0xdc00 && (c) < 0xe000)
#define SURROGATE_VALUE(leading, trailing) \
(((((leading) - 0xd800) << 10) | ((trailing) - 0xdc00)) + 0x10000)
#define REPLACEMENT_CHARACTER 0x0FFFD
static char *
utf_16le_to_utf_8_truncated(const wchar_t *utf_16, char *utf_8,
size_t utf_8_len)
{
wchar_t c, c2;
uint32_t uc;
if (utf_8_len == 0) {
/*
* Not even enough room for a trailing '\0'.
* Don't put anything into the buffer.
*/
return (utf_8);
}
while ((c = *utf_16++) != '\0') {
if (IS_LEADING_SURROGATE(c)) {
/*
* Leading surrogate. Must be followed by
* a trailing surrogate.
*/
c2 = *utf_16;
if (c2 == '\0') {
/*
* Oops, string ends with a lead
* surrogate. Try to drop in
* a REPLACEMENT CHARACTER, and
* don't move the string pointer,
* so on the next trip through
* the loop we grab the terminating
* '\0' and quit.
*/
uc = REPLACEMENT_CHARACTER;
} else {
/*
* OK, we can consume this 2-octet
* value.
*/
utf_16++;
if (IS_TRAILING_SURROGATE(c2)) {
/*
* Trailing surrogate.
* This calculation will,
* for c being a leading
* surrogate and c2 being
* a trailing surrogate,
* produce a value between
* 0x100000 and 0x10ffff,
* so it's always going to be
* a valid Unicode code point.
*/
uc = SURROGATE_VALUE(c, c2);
} else {
/*
* Not a trailing surrogate;
* try to drop in a
* REPLACEMENT CHARACTER.
*/
uc = REPLACEMENT_CHARACTER;
}
}
} else {
/*
* Not a leading surrogate.
*/
if (IS_TRAILING_SURROGATE(c)) {
/*
* Trailing surrogate without
* a preceding leading surrogate.
* Try to drop in a REPLACEMENT
* CHARACTER.
*/
uc = REPLACEMENT_CHARACTER;
} else {
/*
* This is a valid BMP character;
* drop it in.
*/
uc = c;
}
}
/*
* OK, uc is a valid Unicode character; how
* many bytes worth of UTF-8 does it require?
*/
if (uc < 0x0080) {
/* 1 byte. */
if (utf_8_len < 2) {
/*
* Not enough room for that byte
* plus a trailing '\0'.
*/
break;
}
*utf_8++ = (char)uc;
utf_8_len--;
} else if (uc < 0x0800) {
/* 2 bytes. */
if (utf_8_len < 3) {
/*
* Not enough room for those bytes
* plus a trailing '\0'.
*/
break;
}
*utf_8++ = ((uc >> 6) & 0x3F) | 0xC0;
*utf_8++ = ((uc >> 0) & 0x3F) | 0x80;
utf_8_len -= 2;
} else if (uc < 0x010000) {
/* 3 bytes. */
if (utf_8_len < 4) {
/*
* Not enough room for those bytes
* plus a trailing '\0'.
*/
break;
}
*utf_8++ = ((uc >> 12) & 0x0F) | 0xE0;
*utf_8++ = ((uc >> 6) & 0x3F) | 0x80;
*utf_8++ = ((uc >> 0) & 0x3F) | 0x80;
utf_8_len -= 3;
} else {
/* 4 bytes. */
if (utf_8_len < 5) {
/*
* Not enough room for those bytes
* plus a trailing '\0'.
*/
break;
}
*utf_8++ = ((uc >> 18) & 0x03) | 0xF0;
*utf_8++ = ((uc >> 12) & 0x3F) | 0x80;
*utf_8++ = ((uc >> 6) & 0x3F) | 0x80;
*utf_8++ = ((uc >> 0) & 0x3F) | 0x80;
utf_8_len -= 3;
}
}
/*
* OK, we have enough room for (at least) a trailing '\0'.
* (We started out with enough room, thanks to the test
* for a zero-length buffer at the beginning, and if
* there wasn't enough room for any character we wanted
* to put into the buffer *plus* a trailing '\0',
* we'd have quit before putting it into the buffer,
* and thus would have left enough room for the trailing
* '\0'.)
*
* Drop it in.
*/
*utf_8 = '\0';
/*
* Return a pointer to the terminating '\0', in case we
* want to drop something in after that.
*/
return (utf_8);
}
#endif /* _WIN32 */
/*
* Generate an error message based on a format, arguments, and an
* errno, with a message for the errno after the formatted output.
*/
void
pcapint_fmt_errmsg_for_errno(char *errbuf, size_t errbuflen, int errnum,
const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
pcapint_vfmt_errmsg_for_errno(errbuf, errbuflen, errnum, fmt, ap);
va_end(ap);
}
void
pcapint_vfmt_errmsg_for_errno(char *errbuf, size_t errbuflen, int errnum,
const char *fmt, va_list ap)
{
size_t msglen;
char *p;
size_t errbuflen_remaining;
(void)vsnprintf(errbuf, errbuflen, fmt, ap);
msglen = strlen(errbuf);
/*
* Do we have enough space to append ": "?
* Including the terminating '\0', that's 3 bytes.
*/
if (msglen + 3 > errbuflen) {
/* No - just give them what we've produced. */
return;
}
p = errbuf + msglen;
errbuflen_remaining = errbuflen - msglen;
*p++ = ':';
*p++ = ' ';
*p = '\0';
errbuflen_remaining -= 2;
/*
* Now append the string for the error code.
*/
#if defined(HAVE__WCSERROR_S)
/*
* We have a Windows-style _wcserror_s().
* Generate a UTF-16LE error message.
*/
wchar_t utf_16_errbuf[PCAP_ERRBUF_SIZE];
errno_t err = _wcserror_s(utf_16_errbuf, PCAP_ERRBUF_SIZE, errnum);
if (err != 0) {
/*
* It doesn't appear to be documented anywhere obvious
* what the error returns from _wcserror_s().
*/
snprintf(p, errbuflen_remaining, "Error %d", errnum);
return;
}
/*
* Now convert it from UTF-16LE to UTF-8, dropping it in the
* remaining space in the buffer, and truncating it - cleanly,
* on a UTF-8 character boundary - if it doesn't fit.
*/
utf_16le_to_utf_8_truncated(utf_16_errbuf, p, errbuflen_remaining);
/*
* Now, if we're not in UTF-8 mode, convert errbuf to the
* local code page.
*/
if (!use_utf_8)
utf_8_to_acp_truncated(errbuf);
#else
/*
* Either Windows without _wcserror_s() or not Windows. Let pcap_strerror()
* solve the non-UTF-16 part of this problem space.
*/
snprintf(p, errbuflen_remaining, "%s", pcap_strerror(errnum));
#endif
}
#ifdef _WIN32
/*
* Generate an error message based on a format, arguments, and a
* Win32 error, with a message for the Win32 error after the formatted output.
*/
void
pcapint_fmt_errmsg_for_win32_err(char *errbuf, size_t errbuflen, DWORD errnum,
const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
pcapint_vfmt_errmsg_for_win32_err(errbuf, errbuflen, errnum, fmt, ap);
va_end(ap);
}
void
pcapint_vfmt_errmsg_for_win32_err(char *errbuf, size_t errbuflen, DWORD errnum,
const char *fmt, va_list ap)
{
size_t msglen;
char *p;
size_t errbuflen_remaining;
DWORD retval;
wchar_t utf_16_errbuf[PCAP_ERRBUF_SIZE];
size_t utf_8_len;
vsnprintf(errbuf, errbuflen, fmt, ap);
msglen = strlen(errbuf);
/*
* Do we have enough space to append ": "?
* Including the terminating '\0', that's 3 bytes.
*/
if (msglen + 3 > errbuflen) {
/* No - just give them what we've produced. */
return;
}
p = errbuf + msglen;
errbuflen_remaining = errbuflen - msglen;
*p++ = ':';
*p++ = ' ';
*p = '\0';
msglen += 2;
errbuflen_remaining -= 2;
/*
* Now append the string for the error code.
*
* XXX - what language ID to use?
*
* For UN*Xes, pcap_strerror() may or may not return localized
* strings.
*
* We currently don't have localized messages for libpcap, but
* we might want to do so. On the other hand, if most of these
* messages are going to be read by libpcap developers and
* perhaps by developers of libpcap-based applications, English
* might be a better choice, so the developer doesn't have to
* get the message translated if it's in a language they don't
* happen to understand.
*/
retval = FormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS|FORMAT_MESSAGE_MAX_WIDTH_MASK,
NULL, errnum, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
utf_16_errbuf, PCAP_ERRBUF_SIZE, NULL);
if (retval == 0) {
/*
* Failed.
*/
snprintf(p, errbuflen_remaining,
"Couldn't get error message for error (%lu)", errnum);
return;
}
/*
* Now convert it from UTF-16LE to UTF-8.
*/
p = utf_16le_to_utf_8_truncated(utf_16_errbuf, p, errbuflen_remaining);
/*
* Now append the error number, if it fits.
*/
utf_8_len = p - errbuf;
errbuflen_remaining -= utf_8_len;
if (utf_8_len == 0) {
/* The message was empty. */
snprintf(p, errbuflen_remaining, "(%lu)", errnum);
} else
snprintf(p, errbuflen_remaining, " (%lu)", errnum);
/*
* Now, if we're not in UTF-8 mode, convert errbuf to the
* local code page.
*/
if (!use_utf_8)
utf_8_to_acp_truncated(errbuf);
}
#endif