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openssl/crypto/bio/b_print.c
Matt Caswell 9cb177301f Fix memory issues in BIO_*printf functions 
The internal |fmtstr| function used in processing a "%s" format string
in the BIO_*printf functions could overflow while calculating the length
of a string and cause an OOB read when printing very long strings.

Additionally the internal |doapr_outch| function can attempt to write to
an OOB memory location (at an offset from the NULL pointer) in the event of
a memory allocation failure. In 1.0.2 and below this could be caused where
the size of a buffer to be allocated is greater than INT_MAX. E.g. this
could be in processing a very long "%s" format string. Memory leaks can also
occur.

These issues will only occur on certain platforms where sizeof(size_t) >
sizeof(int). E.g. many 64 bit systems. The first issue may mask the second
issue dependent on compiler behaviour.

These problems could enable attacks where large amounts of untrusted data
is passed to the BIO_*printf functions. If applications use these functions
in this way then they could be vulnerable. OpenSSL itself uses these
functions when printing out human-readable dumps of ASN.1 data. Therefore
applications that print this data could be vulnerable if the data is from
untrusted sources. OpenSSL command line applications could also be
vulnerable where they print out ASN.1 data, or if untrusted data is passed
as command line arguments.

Libssl is not considered directly vulnerable. Additionally certificates etc
received via remote connections via libssl are also unlikely to be able to
trigger these issues because of message size limits enforced within libssl.

CVE-2016-0799

Issue reported by Guido Vranken.

Reviewed-by: Andy Polyakov <appro@openssl.org>
2016-02-25 22:45:58 +00:00

860 lines
25 KiB
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/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* 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 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 cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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 AUTHOR 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.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
/* disable assert() unless BIO_DEBUG has been defined */
#ifndef BIO_DEBUG
# ifndef NDEBUG
# define NDEBUG
# endif
#endif
/*
* Stolen from tjh's ssl/ssl_trc.c stuff.
*/
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <assert.h>
#include <limits.h>
#include "internal/cryptlib.h"
#ifndef NO_SYS_TYPES_H
# include <sys/types.h>
#endif
#include <openssl/bn.h> /* To get BN_LLONG properly defined */
#include <openssl/bio.h>
#if defined(BN_LLONG) || defined(SIXTY_FOUR_BIT)
# ifndef HAVE_LONG_LONG
# define HAVE_LONG_LONG 1
# endif
#endif
/***************************************************************************/
/*
* Copyright Patrick Powell 1995
* This code is based on code written by Patrick Powell <papowell@astart.com>
* It may be used for any purpose as long as this notice remains intact
* on all source code distributions.
*/
/*-
* This code contains numerious changes and enhancements which were
* made by lots of contributors over the last years to Patrick Powell's
* original code:
*
* o Patrick Powell <papowell@astart.com> (1995)
* o Brandon Long <blong@fiction.net> (1996, for Mutt)
* o Thomas Roessler <roessler@guug.de> (1998, for Mutt)
* o Michael Elkins <me@cs.hmc.edu> (1998, for Mutt)
* o Andrew Tridgell <tridge@samba.org> (1998, for Samba)
* o Luke Mewburn <lukem@netbsd.org> (1999, for LukemFTP)
* o Ralf S. Engelschall <rse@engelschall.com> (1999, for Pth)
* o ... (for OpenSSL)
*/
#ifdef HAVE_LONG_DOUBLE
# define LDOUBLE long double
#else
# define LDOUBLE double
#endif
#ifdef HAVE_LONG_LONG
# if defined(_WIN32) && !defined(__GNUC__)
# define LLONG __int64
# else
# define LLONG long long
# endif
#else
# define LLONG long
#endif
static int fmtstr(char **, char **, size_t *, size_t *,
const char *, int, int, int);
static int fmtint(char **, char **, size_t *, size_t *,
LLONG, int, int, int, int);
static int fmtfp(char **, char **, size_t *, size_t *,
LDOUBLE, int, int, int);
static int doapr_outch(char **, char **, size_t *, size_t *, int);
static int _dopr(char **sbuffer, char **buffer,
size_t *maxlen, size_t *retlen, int *truncated,
const char *format, va_list args);
/* format read states */
#define DP_S_DEFAULT 0
#define DP_S_FLAGS 1
#define DP_S_MIN 2
#define DP_S_DOT 3
#define DP_S_MAX 4
#define DP_S_MOD 5
#define DP_S_CONV 6
#define DP_S_DONE 7
/* format flags - Bits */
#define DP_F_MINUS (1 << 0)
#define DP_F_PLUS (1 << 1)
#define DP_F_SPACE (1 << 2)
#define DP_F_NUM (1 << 3)
#define DP_F_ZERO (1 << 4)
#define DP_F_UP (1 << 5)
#define DP_F_UNSIGNED (1 << 6)
/* conversion flags */
#define DP_C_SHORT 1
#define DP_C_LONG 2
#define DP_C_LDOUBLE 3
#define DP_C_LLONG 4
/* some handy macros */
#define char_to_int(p) (p - '0')
#define OSSL_MAX(p,q) ((p >= q) ? p : q)
static int
_dopr(char **sbuffer,
char **buffer,
size_t *maxlen,
size_t *retlen, int *truncated, const char *format, va_list args)
{
char ch;
LLONG value;
LDOUBLE fvalue;
char *strvalue;
int min;
int max;
int state;
int flags;
int cflags;
size_t currlen;
state = DP_S_DEFAULT;
flags = currlen = cflags = min = 0;
max = -1;
ch = *format++;
while (state != DP_S_DONE) {
if (ch == '\0' || (buffer == NULL && currlen >= *maxlen))
state = DP_S_DONE;
switch (state) {
case DP_S_DEFAULT:
if (ch == '%')
state = DP_S_FLAGS;
else
if(!doapr_outch(sbuffer, buffer, &currlen, maxlen, ch))
return 0;
ch = *format++;
break;
case DP_S_FLAGS:
switch (ch) {
case '-':
flags |= DP_F_MINUS;
ch = *format++;
break;
case '+':
flags |= DP_F_PLUS;
ch = *format++;
break;
case ' ':
flags |= DP_F_SPACE;
ch = *format++;
break;
case '#':
flags |= DP_F_NUM;
ch = *format++;
break;
case '0':
flags |= DP_F_ZERO;
ch = *format++;
break;
default:
state = DP_S_MIN;
break;
}
break;
case DP_S_MIN:
if (isdigit((unsigned char)ch)) {
min = 10 * min + char_to_int(ch);
ch = *format++;
} else if (ch == '*') {
min = va_arg(args, int);
ch = *format++;
state = DP_S_DOT;
} else
state = DP_S_DOT;
break;
case DP_S_DOT:
if (ch == '.') {
state = DP_S_MAX;
ch = *format++;
} else
state = DP_S_MOD;
break;
case DP_S_MAX:
if (isdigit((unsigned char)ch)) {
if (max < 0)
max = 0;
max = 10 * max + char_to_int(ch);
ch = *format++;
} else if (ch == '*') {
max = va_arg(args, int);
ch = *format++;
state = DP_S_MOD;
} else
state = DP_S_MOD;
break;
case DP_S_MOD:
switch (ch) {
case 'h':
cflags = DP_C_SHORT;
ch = *format++;
break;
case 'l':
if (*format == 'l') {
cflags = DP_C_LLONG;
format++;
} else
cflags = DP_C_LONG;
ch = *format++;
break;
case 'q':
cflags = DP_C_LLONG;
ch = *format++;
break;
case 'L':
cflags = DP_C_LDOUBLE;
ch = *format++;
break;
default:
break;
}
state = DP_S_CONV;
break;
case DP_S_CONV:
switch (ch) {
case 'd':
case 'i':
switch (cflags) {
case DP_C_SHORT:
value = (short int)va_arg(args, int);
break;
case DP_C_LONG:
value = va_arg(args, long int);
break;
case DP_C_LLONG:
value = va_arg(args, LLONG);
break;
default:
value = va_arg(args, int);
break;
}
if (!fmtint(sbuffer, buffer, &currlen, maxlen, value, 10, min,
max, flags))
return 0;
break;
case 'X':
flags |= DP_F_UP;
/* FALLTHROUGH */
case 'x':
case 'o':
case 'u':
flags |= DP_F_UNSIGNED;
switch (cflags) {
case DP_C_SHORT:
value = (unsigned short int)va_arg(args, unsigned int);
break;
case DP_C_LONG:
value = (LLONG) va_arg(args, unsigned long int);
break;
case DP_C_LLONG:
value = va_arg(args, unsigned LLONG);
break;
default:
value = (LLONG) va_arg(args, unsigned int);
break;
}
if (!fmtint(sbuffer, buffer, &currlen, maxlen, value,
ch == 'o' ? 8 : (ch == 'u' ? 10 : 16),
min, max, flags))
return 0;
break;
case 'f':
if (cflags == DP_C_LDOUBLE)
fvalue = va_arg(args, LDOUBLE);
else
fvalue = va_arg(args, double);
if (!fmtfp(sbuffer, buffer, &currlen, maxlen, fvalue, min, max,
flags))
return 0;
break;
case 'E':
flags |= DP_F_UP;
case 'e':
if (cflags == DP_C_LDOUBLE)
fvalue = va_arg(args, LDOUBLE);
else
fvalue = va_arg(args, double);
break;
case 'G':
flags |= DP_F_UP;
case 'g':
if (cflags == DP_C_LDOUBLE)
fvalue = va_arg(args, LDOUBLE);
else
fvalue = va_arg(args, double);
break;
case 'c':
if(!doapr_outch(sbuffer, buffer, &currlen, maxlen,
va_arg(args, int)))
return 0;
break;
case 's':
strvalue = va_arg(args, char *);
if (max < 0) {
if (buffer)
max = INT_MAX;
else
max = *maxlen;
}
if (!fmtstr(sbuffer, buffer, &currlen, maxlen, strvalue,
flags, min, max))
return 0;
break;
case 'p':
value = (size_t)va_arg(args, void *);
if (!fmtint(sbuffer, buffer, &currlen, maxlen,
value, 16, min, max, flags | DP_F_NUM))
return 0;
break;
case 'n': /* XXX */
if (cflags == DP_C_SHORT) {
short int *num;
num = va_arg(args, short int *);
*num = currlen;
} else if (cflags == DP_C_LONG) { /* XXX */
long int *num;
num = va_arg(args, long int *);
*num = (long int)currlen;
} else if (cflags == DP_C_LLONG) { /* XXX */
LLONG *num;
num = va_arg(args, LLONG *);
*num = (LLONG) currlen;
} else {
int *num;
num = va_arg(args, int *);
*num = currlen;
}
break;
case '%':
if(!doapr_outch(sbuffer, buffer, &currlen, maxlen, ch))
return 0;
break;
case 'w':
/* not supported yet, treat as next char */
ch = *format++;
break;
default:
/* unknown, skip */
break;
}
ch = *format++;
state = DP_S_DEFAULT;
flags = cflags = min = 0;
max = -1;
break;
case DP_S_DONE:
break;
default:
break;
}
}
*truncated = (currlen > *maxlen - 1);
if (*truncated)
currlen = *maxlen - 1;
if(!doapr_outch(sbuffer, buffer, &currlen, maxlen, '\0'))
return 0;
*retlen = currlen - 1;
return 1;
}
static int
fmtstr(char **sbuffer,
char **buffer,
size_t *currlen,
size_t *maxlen, const char *value, int flags, int min, int max)
{
int padlen;
size_t strln;
int cnt = 0;
if (value == 0)
value = "<NULL>";
strln = strlen(value);
if (strln > INT_MAX)
strln = INT_MAX;
padlen = min - strln;
if (min < 0 || padlen < 0)
padlen = 0;
if (flags & DP_F_MINUS)
padlen = -padlen;
while ((padlen > 0) && (cnt < max)) {
if(!doapr_outch(sbuffer, buffer, currlen, maxlen, ' '))
return 0;
--padlen;
++cnt;
}
while (*value && (cnt < max)) {
if(!doapr_outch(sbuffer, buffer, currlen, maxlen, *value++))
return 0;
++cnt;
}
while ((padlen < 0) && (cnt < max)) {
if(!doapr_outch(sbuffer, buffer, currlen, maxlen, ' '))
return 0;
++padlen;
++cnt;
}
return 1;
}
static int
fmtint(char **sbuffer,
char **buffer,
size_t *currlen,
size_t *maxlen, LLONG value, int base, int min, int max, int flags)
{
int signvalue = 0;
const char *prefix = "";
unsigned LLONG uvalue;
char convert[DECIMAL_SIZE(value) + 3];
int place = 0;
int spadlen = 0;
int zpadlen = 0;
int caps = 0;
if (max < 0)
max = 0;
uvalue = value;
if (!(flags & DP_F_UNSIGNED)) {
if (value < 0) {
signvalue = '-';
uvalue = -value;
} else if (flags & DP_F_PLUS)
signvalue = '+';
else if (flags & DP_F_SPACE)
signvalue = ' ';
}
if (flags & DP_F_NUM) {
if (base == 8)
prefix = "0";
if (base == 16)
prefix = "0x";
}
if (flags & DP_F_UP)
caps = 1;
do {
convert[place++] = (caps ? "0123456789ABCDEF" : "0123456789abcdef")
[uvalue % (unsigned)base];
uvalue = (uvalue / (unsigned)base);
} while (uvalue && (place < (int)sizeof(convert)));
if (place == sizeof(convert))
place--;
convert[place] = 0;
zpadlen = max - place;
spadlen =
min - OSSL_MAX(max, place) - (signvalue ? 1 : 0) - strlen(prefix);
if (zpadlen < 0)
zpadlen = 0;
if (spadlen < 0)
spadlen = 0;
if (flags & DP_F_ZERO) {
zpadlen = OSSL_MAX(zpadlen, spadlen);
spadlen = 0;
}
if (flags & DP_F_MINUS)
spadlen = -spadlen;
/* spaces */
while (spadlen > 0) {
if(!doapr_outch(sbuffer, buffer, currlen, maxlen, ' '))
return 0;
--spadlen;
}
/* sign */
if (signvalue)
if(!doapr_outch(sbuffer, buffer, currlen, maxlen, signvalue))
return 0;
/* prefix */
while (*prefix) {
if(!doapr_outch(sbuffer, buffer, currlen, maxlen, *prefix))
return 0;
prefix++;
}
/* zeros */
if (zpadlen > 0) {
while (zpadlen > 0) {
if(!doapr_outch(sbuffer, buffer, currlen, maxlen, '0'))
return 0;
--zpadlen;
}
}
/* digits */
while (place > 0) {
if (!doapr_outch(sbuffer, buffer, currlen, maxlen, convert[--place]))
return 0;
}
/* left justified spaces */
while (spadlen < 0) {
if (!doapr_outch(sbuffer, buffer, currlen, maxlen, ' '))
return 0;
++spadlen;
}
return 1;
}
static LDOUBLE abs_val(LDOUBLE value)
{
LDOUBLE result = value;
if (value < 0)
result = -value;
return result;
}
static LDOUBLE pow_10(int in_exp)
{
LDOUBLE result = 1;
while (in_exp) {
result *= 10;
in_exp--;
}
return result;
}
static long roundv(LDOUBLE value)
{
long intpart;
intpart = (long)value;
value = value - intpart;
if (value >= 0.5)
intpart++;
return intpart;
}
static int
fmtfp(char **sbuffer,
char **buffer,
size_t *currlen,
size_t *maxlen, LDOUBLE fvalue, int min, int max, int flags)
{
int signvalue = 0;
LDOUBLE ufvalue;
char iconvert[20];
char fconvert[20];
int iplace = 0;
int fplace = 0;
int padlen = 0;
int zpadlen = 0;
long intpart;
long fracpart;
long max10;
if (max < 0)
max = 6;
ufvalue = abs_val(fvalue);
if (fvalue < 0)
signvalue = '-';
else if (flags & DP_F_PLUS)
signvalue = '+';
else if (flags & DP_F_SPACE)
signvalue = ' ';
intpart = (long)ufvalue;
/*
* sorry, we only support 9 digits past the decimal because of our
* conversion method
*/
if (max > 9)
max = 9;
/*
* we "cheat" by converting the fractional part to integer by multiplying
* by a factor of 10
*/
max10 = roundv(pow_10(max));
fracpart = roundv(pow_10(max) * (ufvalue - intpart));
if (fracpart >= max10) {
intpart++;
fracpart -= max10;
}
/* convert integer part */
do {
iconvert[iplace++] = "0123456789"[intpart % 10];
intpart = (intpart / 10);
} while (intpart && (iplace < (int)sizeof(iconvert)));
if (iplace == sizeof iconvert)
iplace--;
iconvert[iplace] = 0;
/* convert fractional part */
do {
fconvert[fplace++] = "0123456789"[fracpart % 10];
fracpart = (fracpart / 10);
} while (fplace < max);
if (fplace == sizeof fconvert)
fplace--;
fconvert[fplace] = 0;
/* -1 for decimal point, another -1 if we are printing a sign */
padlen = min - iplace - max - 1 - ((signvalue) ? 1 : 0);
zpadlen = max - fplace;
if (zpadlen < 0)
zpadlen = 0;
if (padlen < 0)
padlen = 0;
if (flags & DP_F_MINUS)
padlen = -padlen;
if ((flags & DP_F_ZERO) && (padlen > 0)) {
if (signvalue) {
if (!doapr_outch(sbuffer, buffer, currlen, maxlen, signvalue))
return 0;
--padlen;
signvalue = 0;
}
while (padlen > 0) {
if (!doapr_outch(sbuffer, buffer, currlen, maxlen, '0'))
return 0;
--padlen;
}
}
while (padlen > 0) {
if (!doapr_outch(sbuffer, buffer, currlen, maxlen, ' '))
return 0;
--padlen;
}
if (signvalue && !doapr_outch(sbuffer, buffer, currlen, maxlen, signvalue))
return 0;
while (iplace > 0) {
if (!doapr_outch(sbuffer, buffer, currlen, maxlen, iconvert[--iplace]))
return 0;
}
/*
* Decimal point. This should probably use locale to find the correct
* char to print out.
*/
if (max > 0 || (flags & DP_F_NUM)) {
if (!doapr_outch(sbuffer, buffer, currlen, maxlen, '.'))
return 0;
while (fplace > 0) {
if(!doapr_outch(sbuffer, buffer, currlen, maxlen,
fconvert[--fplace]))
return 0;
}
}
while (zpadlen > 0) {
if (!doapr_outch(sbuffer, buffer, currlen, maxlen, '0'))
return 0;
--zpadlen;
}
while (padlen < 0) {
if (!doapr_outch(sbuffer, buffer, currlen, maxlen, ' '))
return 0;
++padlen;
}
return 1;
}
#define BUFFER_INC 1024
static int
doapr_outch(char **sbuffer,
char **buffer, size_t *currlen, size_t *maxlen, int c)
{
/* If we haven't at least one buffer, someone has doe a big booboo */
assert(*sbuffer != NULL || buffer != NULL);
/* |currlen| must always be <= |*maxlen| */
assert(*currlen <= *maxlen);
if (buffer && *currlen == *maxlen) {
if (*maxlen > INT_MAX - BUFFER_INC)
return 0;
*maxlen += BUFFER_INC;
if (*buffer == NULL) {
*buffer = OPENSSL_malloc(*maxlen);
if (*buffer == NULL)
return 0;
if (*currlen > 0) {
assert(*sbuffer != NULL);
memcpy(*buffer, *sbuffer, *currlen);
}
*sbuffer = NULL;
} else {
char *tmpbuf;
tmpbuf = OPENSSL_realloc(*buffer, *maxlen);
if (tmpbuf == NULL)
return 0;
*buffer = tmpbuf;
}
}
if (*currlen < *maxlen) {
if (*sbuffer)
(*sbuffer)[(*currlen)++] = (char)c;
else
(*buffer)[(*currlen)++] = (char)c;
}
return 1;
}
/***************************************************************************/
int BIO_printf(BIO *bio, const char *format, ...)
{
va_list args;
int ret;
va_start(args, format);
ret = BIO_vprintf(bio, format, args);
va_end(args);
return (ret);
}
int BIO_vprintf(BIO *bio, const char *format, va_list args)
{
int ret;
size_t retlen;
char hugebuf[1024 * 2]; /* Was previously 10k, which is unreasonable
* in small-stack environments, like threads
* or DOS programs. */
char *hugebufp = hugebuf;
size_t hugebufsize = sizeof(hugebuf);
char *dynbuf = NULL;
int ignored;
dynbuf = NULL;
if (!_dopr(&hugebufp, &dynbuf, &hugebufsize, &retlen, &ignored, format,
args)) {
OPENSSL_free(dynbuf);
return -1;
}
if (dynbuf) {
ret = BIO_write(bio, dynbuf, (int)retlen);
OPENSSL_free(dynbuf);
} else {
ret = BIO_write(bio, hugebuf, (int)retlen);
}
return (ret);
}
/*
* As snprintf is not available everywhere, we provide our own
* implementation. This function has nothing to do with BIOs, but it's
* closely related to BIO_printf, and we need *some* name prefix ... (XXX the
* function should be renamed, but to what?)
*/
int BIO_snprintf(char *buf, size_t n, const char *format, ...)
{
va_list args;
int ret;
va_start(args, format);
ret = BIO_vsnprintf(buf, n, format, args);
va_end(args);
return (ret);
}
int BIO_vsnprintf(char *buf, size_t n, const char *format, va_list args)
{
size_t retlen;
int truncated;
if(!_dopr(&buf, NULL, &n, &retlen, &truncated, format, args))
return -1;
if (truncated)
/*
* In case of truncation, return -1 like traditional snprintf.
* (Current drafts for ISO/IEC 9899 say snprintf should return the
* number of characters that would have been written, had the buffer
* been large enough.)
*/
return -1;
else
return (retlen <= INT_MAX) ? (int)retlen : -1;
}
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