Revision ce052c8437fb97cbc57f034fa94b5bcd749dbf52 authored by Matt Caswell on 03 December 2015, 14:56:22 UTC, committed by Matt Caswell on 03 December 2015, 14:56:22 UTC
Reviewed-by: Richard Levitte <levitte@openssl.org>
1 parent a402b2b
s2_pkt.c
/* ssl/s2_pkt.c */
/* 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.]
*/
/* ====================================================================
* Copyright (c) 1998-2001 The OpenSSL Project. 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 acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@openssl.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED 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 OpenSSL PROJECT OR
* ITS 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.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
#include "ssl_locl.h"
#ifndef OPENSSL_NO_SSL2
# include <stdio.h>
# include <errno.h>
# define USE_SOCKETS
static int read_n(SSL *s, unsigned int n, unsigned int max,
unsigned int extend);
static int n_do_ssl_write(SSL *s, const unsigned char *buf, unsigned int len);
static int write_pending(SSL *s, const unsigned char *buf, unsigned int len);
static int ssl_mt_error(int n);
/*
* SSL 2.0 imlementation for SSL_read/SSL_peek - This routine will return 0
* to len bytes, decrypted etc if required.
*/
static int ssl2_read_internal(SSL *s, void *buf, int len, int peek)
{
int n;
unsigned char mac[MAX_MAC_SIZE];
unsigned char *p;
int i;
int mac_size;
ssl2_read_again:
if (SSL_in_init(s) && !s->in_handshake) {
n = s->handshake_func(s);
if (n < 0)
return (n);
if (n == 0) {
SSLerr(SSL_F_SSL2_READ_INTERNAL, SSL_R_SSL_HANDSHAKE_FAILURE);
return (-1);
}
}
clear_sys_error();
s->rwstate = SSL_NOTHING;
if (len <= 0)
return (len);
if (s->s2->ract_data_length != 0) { /* read from buffer */
if (len > s->s2->ract_data_length)
n = s->s2->ract_data_length;
else
n = len;
memcpy(buf, s->s2->ract_data, (unsigned int)n);
if (!peek) {
s->s2->ract_data_length -= n;
s->s2->ract_data += n;
if (s->s2->ract_data_length == 0)
s->rstate = SSL_ST_READ_HEADER;
}
return (n);
}
/*
* s->s2->ract_data_length == 0 Fill the buffer, then goto
* ssl2_read_again.
*/
if (s->rstate == SSL_ST_READ_HEADER) {
if (s->first_packet) {
n = read_n(s, 5, SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER + 2, 0);
if (n <= 0)
return (n); /* error or non-blocking */
s->first_packet = 0;
p = s->packet;
if (!((p[0] & 0x80) && ((p[2] == SSL2_MT_CLIENT_HELLO) ||
(p[2] == SSL2_MT_SERVER_HELLO)))) {
SSLerr(SSL_F_SSL2_READ_INTERNAL,
SSL_R_NON_SSLV2_INITIAL_PACKET);
return (-1);
}
} else {
n = read_n(s, 2, SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER + 2, 0);
if (n <= 0)
return (n); /* error or non-blocking */
}
/* part read stuff */
s->rstate = SSL_ST_READ_BODY;
p = s->packet;
/* Do header */
/*
* s->s2->padding=0;
*/
s->s2->escape = 0;
s->s2->rlength = (((unsigned int)p[0]) << 8) | ((unsigned int)p[1]);
if ((p[0] & TWO_BYTE_BIT)) { /* Two byte header? */
s->s2->three_byte_header = 0;
s->s2->rlength &= TWO_BYTE_MASK;
} else {
s->s2->three_byte_header = 1;
s->s2->rlength &= THREE_BYTE_MASK;
/* security >s2->escape */
s->s2->escape = ((p[0] & SEC_ESC_BIT)) ? 1 : 0;
}
}
if (s->rstate == SSL_ST_READ_BODY) {
n = s->s2->rlength + 2 + s->s2->three_byte_header;
if (n > (int)s->packet_length) {
n -= s->packet_length;
i = read_n(s, (unsigned int)n, (unsigned int)n, 1);
if (i <= 0)
return (i); /* ERROR */
}
p = &(s->packet[2]);
s->rstate = SSL_ST_READ_HEADER;
if (s->s2->three_byte_header)
s->s2->padding = *(p++);
else
s->s2->padding = 0;
/* Data portion */
if (s->s2->clear_text) {
mac_size = 0;
s->s2->mac_data = p;
s->s2->ract_data = p;
if (s->s2->padding) {
SSLerr(SSL_F_SSL2_READ_INTERNAL, SSL_R_ILLEGAL_PADDING);
return (-1);
}
} else {
mac_size = EVP_MD_CTX_size(s->read_hash);
if (mac_size < 0)
return -1;
OPENSSL_assert(mac_size <= MAX_MAC_SIZE);
s->s2->mac_data = p;
s->s2->ract_data = &p[mac_size];
if (s->s2->padding + mac_size > s->s2->rlength) {
SSLerr(SSL_F_SSL2_READ_INTERNAL, SSL_R_ILLEGAL_PADDING);
return (-1);
}
}
s->s2->ract_data_length = s->s2->rlength;
/*
* added a check for length > max_size in case encryption was not
* turned on yet due to an error
*/
if ((!s->s2->clear_text) &&
(s->s2->rlength >= (unsigned int)mac_size)) {
if (!ssl2_enc(s, 0)) {
SSLerr(SSL_F_SSL2_READ_INTERNAL, SSL_R_DECRYPTION_FAILED);
return (-1);
}
s->s2->ract_data_length -= mac_size;
ssl2_mac(s, mac, 0);
s->s2->ract_data_length -= s->s2->padding;
if ((CRYPTO_memcmp(mac, s->s2->mac_data, mac_size) != 0) ||
(s->s2->rlength %
EVP_CIPHER_CTX_block_size(s->enc_read_ctx) != 0)) {
SSLerr(SSL_F_SSL2_READ_INTERNAL, SSL_R_BAD_MAC_DECODE);
return (-1);
}
}
INC32(s->s2->read_sequence); /* expect next number */
/* s->s2->ract_data is now available for processing */
/*
* Possibly the packet that we just read had 0 actual data bytes.
* (SSLeay/OpenSSL itself never sends such packets; see ssl2_write.)
* In this case, returning 0 would be interpreted by the caller as
* indicating EOF, so it's not a good idea. Instead, we just
* continue reading; thus ssl2_read_internal may have to process
* multiple packets before it can return. [Note that using select()
* for blocking sockets *never* guarantees that the next SSL_read
* will not block -- the available data may contain incomplete
* packets, and except for SSL 2, renegotiation can confuse things
* even more.]
*/
goto ssl2_read_again; /* This should really be "return
* ssl2_read(s,buf,len)", but that would
* allow for denial-of-service attacks if a C
* compiler is used that does not recognize
* end-recursion. */
} else {
SSLerr(SSL_F_SSL2_READ_INTERNAL, SSL_R_BAD_STATE);
return (-1);
}
}
int ssl2_read(SSL *s, void *buf, int len)
{
return ssl2_read_internal(s, buf, len, 0);
}
int ssl2_peek(SSL *s, void *buf, int len)
{
return ssl2_read_internal(s, buf, len, 1);
}
static int read_n(SSL *s, unsigned int n, unsigned int max,
unsigned int extend)
{
int i, off, newb;
/*
* if there is stuff still in the buffer from a previous read, and there
* is more than we want, take some.
*/
if (s->s2->rbuf_left >= (int)n) {
if (extend)
s->packet_length += n;
else {
s->packet = &(s->s2->rbuf[s->s2->rbuf_offs]);
s->packet_length = n;
}
s->s2->rbuf_left -= n;
s->s2->rbuf_offs += n;
return (n);
}
if (!s->read_ahead)
max = n;
if (max > (unsigned int)(SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER + 2))
max = SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER + 2;
/*
* Else we want more than we have. First, if there is some left or we
* want to extend
*/
off = 0;
if ((s->s2->rbuf_left != 0) || ((s->packet_length != 0) && extend)) {
newb = s->s2->rbuf_left;
if (extend) {
off = s->packet_length;
if (s->packet != s->s2->rbuf)
memcpy(s->s2->rbuf, s->packet, (unsigned int)newb + off);
} else if (s->s2->rbuf_offs != 0) {
memcpy(s->s2->rbuf, &(s->s2->rbuf[s->s2->rbuf_offs]),
(unsigned int)newb);
s->s2->rbuf_offs = 0;
}
s->s2->rbuf_left = 0;
} else
newb = 0;
/*
* off is the offset to start writing too. r->s2->rbuf_offs is the
* 'unread data', now 0. newb is the number of new bytes so far
*/
s->packet = s->s2->rbuf;
while (newb < (int)n) {
clear_sys_error();
if (s->rbio != NULL) {
s->rwstate = SSL_READING;
i = BIO_read(s->rbio, (char *)&(s->s2->rbuf[off + newb]),
max - newb);
} else {
SSLerr(SSL_F_READ_N, SSL_R_READ_BIO_NOT_SET);
i = -1;
}
# ifdef PKT_DEBUG
if (s->debug & 0x01)
sleep(1);
# endif
if (i <= 0) {
s->s2->rbuf_left += newb;
return (i);
}
newb += i;
}
/* record unread data */
if (newb > (int)n) {
s->s2->rbuf_offs = n + off;
s->s2->rbuf_left = newb - n;
} else {
s->s2->rbuf_offs = 0;
s->s2->rbuf_left = 0;
}
if (extend)
s->packet_length += n;
else
s->packet_length = n;
s->rwstate = SSL_NOTHING;
return (n);
}
int ssl2_write(SSL *s, const void *_buf, int len)
{
const unsigned char *buf = _buf;
unsigned int n, tot;
int i;
if (SSL_in_init(s) && !s->in_handshake) {
i = s->handshake_func(s);
if (i < 0)
return (i);
if (i == 0) {
SSLerr(SSL_F_SSL2_WRITE, SSL_R_SSL_HANDSHAKE_FAILURE);
return (-1);
}
}
if (s->error) {
ssl2_write_error(s);
if (s->error)
return (-1);
}
clear_sys_error();
s->rwstate = SSL_NOTHING;
if (len <= 0)
return (len);
tot = s->s2->wnum;
s->s2->wnum = 0;
n = (len - tot);
for (;;) {
i = n_do_ssl_write(s, &(buf[tot]), n);
if (i <= 0) {
s->s2->wnum = tot;
return (i);
}
if ((i == (int)n) || (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)) {
return (tot + i);
}
n -= i;
tot += i;
}
}
static int write_pending(SSL *s, const unsigned char *buf, unsigned int len)
{
int i;
/* s->s2->wpend_len != 0 MUST be true. */
/*
* check that they have given us the same buffer to write
*/
if ((s->s2->wpend_tot > (int)len) ||
((s->s2->wpend_buf != buf) &&
!(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))) {
SSLerr(SSL_F_WRITE_PENDING, SSL_R_BAD_WRITE_RETRY);
return (-1);
}
for (;;) {
clear_sys_error();
if (s->wbio != NULL) {
s->rwstate = SSL_WRITING;
i = BIO_write(s->wbio,
(char *)&(s->s2->write_ptr[s->s2->wpend_off]),
(unsigned int)s->s2->wpend_len);
} else {
SSLerr(SSL_F_WRITE_PENDING, SSL_R_WRITE_BIO_NOT_SET);
i = -1;
}
# ifdef PKT_DEBUG
if (s->debug & 0x01)
sleep(1);
# endif
if (i == s->s2->wpend_len) {
s->s2->wpend_len = 0;
s->rwstate = SSL_NOTHING;
return (s->s2->wpend_ret);
} else if (i <= 0)
return (i);
s->s2->wpend_off += i;
s->s2->wpend_len -= i;
}
}
static int n_do_ssl_write(SSL *s, const unsigned char *buf, unsigned int len)
{
unsigned int j, k, olen, p, bs;
int mac_size;
register unsigned char *pp;
olen = len;
/*
* first check if there is data from an encryption waiting to be sent -
* it must be sent because the other end is waiting. This will happen
* with non-blocking IO. We print it and then return.
*/
if (s->s2->wpend_len != 0)
return (write_pending(s, buf, len));
/* set mac_size to mac size */
if (s->s2->clear_text)
mac_size = 0;
else {
mac_size = EVP_MD_CTX_size(s->write_hash);
if (mac_size < 0)
return -1;
}
/* lets set the pad p */
if (s->s2->clear_text) {
if (len > SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER)
len = SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER;
p = 0;
s->s2->three_byte_header = 0;
/* len=len; */
} else {
bs = EVP_CIPHER_CTX_block_size(s->enc_read_ctx);
j = len + mac_size;
/*
* Two-byte headers allow for a larger record length than three-byte
* headers, but we can't use them if we need padding or if we have to
* set the escape bit.
*/
if ((j > SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER) && (!s->s2->escape)) {
if (j > SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER)
j = SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER;
/*
* set k to the max number of bytes with 2 byte header
*/
k = j - (j % bs);
/* how many data bytes? */
len = k - mac_size;
s->s2->three_byte_header = 0;
p = 0;
} else if ((bs <= 1) && (!s->s2->escape)) {
/*-
* j <= SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER, thus
* j < SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER
*/
s->s2->three_byte_header = 0;
p = 0;
} else { /* we may have to use a 3 byte header */
/*-
* If s->s2->escape is not set, then
* j <= SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER, and thus
* j < SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER.
*/
p = (j % bs);
p = (p == 0) ? 0 : (bs - p);
if (s->s2->escape) {
s->s2->three_byte_header = 1;
if (j > SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER)
j = SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER;
} else
s->s2->three_byte_header = (p == 0) ? 0 : 1;
}
}
/*-
* Now
* j <= SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER
* holds, and if s->s2->three_byte_header is set, then even
* j <= SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER.
*/
/*
* mac_size is the number of MAC bytes len is the number of data bytes we
* are going to send p is the number of padding bytes (if it is a
* two-byte header, then p == 0)
*/
s->s2->wlength = len;
s->s2->padding = p;
s->s2->mac_data = &(s->s2->wbuf[3]);
s->s2->wact_data = &(s->s2->wbuf[3 + mac_size]);
/* we copy the data into s->s2->wbuf */
memcpy(s->s2->wact_data, buf, len);
if (p)
memset(&(s->s2->wact_data[len]), 0, p); /* arbitrary padding */
if (!s->s2->clear_text) {
s->s2->wact_data_length = len + p;
ssl2_mac(s, s->s2->mac_data, 1);
s->s2->wlength += p + mac_size;
if (ssl2_enc(s, 1) < 1)
return -1;
}
/* package up the header */
s->s2->wpend_len = s->s2->wlength;
if (s->s2->three_byte_header) { /* 3 byte header */
pp = s->s2->mac_data;
pp -= 3;
pp[0] = (s->s2->wlength >> 8) & (THREE_BYTE_MASK >> 8);
if (s->s2->escape)
pp[0] |= SEC_ESC_BIT;
pp[1] = s->s2->wlength & 0xff;
pp[2] = s->s2->padding;
s->s2->wpend_len += 3;
} else {
pp = s->s2->mac_data;
pp -= 2;
pp[0] = ((s->s2->wlength >> 8) & (TWO_BYTE_MASK >> 8)) | TWO_BYTE_BIT;
pp[1] = s->s2->wlength & 0xff;
s->s2->wpend_len += 2;
}
s->s2->write_ptr = pp;
INC32(s->s2->write_sequence); /* expect next number */
/* lets try to actually write the data */
s->s2->wpend_tot = olen;
s->s2->wpend_buf = buf;
s->s2->wpend_ret = len;
s->s2->wpend_off = 0;
return (write_pending(s, buf, olen));
}
int ssl2_part_read(SSL *s, unsigned long f, int i)
{
unsigned char *p;
int j;
if (i < 0) {
/* ssl2_return_error(s); */
/*
* for non-blocking io, this is not necessarily fatal
*/
return (i);
} else {
s->init_num += i;
/*
* Check for error. While there are recoverable errors, this
* function is not called when those must be expected; any error
* detected here is fatal.
*/
if (s->init_num >= 3) {
p = (unsigned char *)s->init_buf->data;
if (p[0] == SSL2_MT_ERROR) {
j = (p[1] << 8) | p[2];
SSLerr((int)f, ssl_mt_error(j));
s->init_num -= 3;
if (s->init_num > 0)
memmove(p, p + 3, s->init_num);
}
}
/*
* If it's not an error message, we have some error anyway -- the
* message was shorter than expected. This too is treated as fatal
* (at least if SSL_get_error is asked for its opinion).
*/
return (0);
}
}
int ssl2_do_write(SSL *s)
{
int ret;
ret = ssl2_write(s, &s->init_buf->data[s->init_off], s->init_num);
if (ret == s->init_num) {
if (s->msg_callback)
s->msg_callback(1, s->version, 0, s->init_buf->data,
(size_t)(s->init_off + s->init_num), s,
s->msg_callback_arg);
return (1);
}
if (ret < 0)
return (-1);
s->init_off += ret;
s->init_num -= ret;
return (0);
}
static int ssl_mt_error(int n)
{
int ret;
switch (n) {
case SSL2_PE_NO_CIPHER:
ret = SSL_R_PEER_ERROR_NO_CIPHER;
break;
case SSL2_PE_NO_CERTIFICATE:
ret = SSL_R_PEER_ERROR_NO_CERTIFICATE;
break;
case SSL2_PE_BAD_CERTIFICATE:
ret = SSL_R_PEER_ERROR_CERTIFICATE;
break;
case SSL2_PE_UNSUPPORTED_CERTIFICATE_TYPE:
ret = SSL_R_PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE;
break;
default:
ret = SSL_R_UNKNOWN_REMOTE_ERROR_TYPE;
break;
}
return (ret);
}
#else /* !OPENSSL_NO_SSL2 */
# if PEDANTIC
static void *dummy = &dummy;
# endif
#endif
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