version 1.30, 2003/09/18 13:02:21 |
version 1.60, 2014/04/30 05:29:56 |
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/* $OpenBSD$ */ |
/* |
/* |
* Author: Tatu Ylonen <ylo@cs.hut.fi> |
* Copyright (c) 2012 Damien Miller <djm@mindrot.org> |
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
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* All rights reserved |
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* Auxiliary functions for storing and retrieving various data types to/from |
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* Buffers. |
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* |
* |
* As far as I am concerned, the code I have written for this software |
* Permission to use, copy, modify, and distribute this software for any |
* can be used freely for any purpose. Any derived versions of this |
* purpose with or without fee is hereby granted, provided that the above |
* software must be clearly marked as such, and if the derived work is |
* copyright notice and this permission notice appear in all copies. |
* incompatible with the protocol description in the RFC file, it must be |
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* called by a name other than "ssh" or "Secure Shell". |
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* |
* |
* |
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
* SSH2 packet format added by Markus Friedl |
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
* Copyright (c) 2000 Markus Friedl. All rights reserved. |
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
* |
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
* Redistribution and use in source and binary forms, with or without |
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
* modification, are permitted provided that the following conditions |
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
* are met: |
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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*/ |
*/ |
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#include "includes.h" |
/* Emulation wrappers for legacy OpenSSH buffer API atop sshbuf */ |
RCSID("$OpenBSD$"); |
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#include <openssl/bn.h> |
#include <sys/types.h> |
#include "bufaux.h" |
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#include "xmalloc.h" |
#include "buffer.h" |
#include "getput.h" |
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#include "log.h" |
#include "log.h" |
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#include "ssherr.h" |
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/* |
int |
* Stores an BIGNUM in the buffer with a 2-byte msb first bit count, followed |
buffer_get_short_ret(u_short *v, Buffer *buffer) |
* by (bits+7)/8 bytes of binary data, msb first. |
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*/ |
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void |
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buffer_put_bignum(Buffer *buffer, BIGNUM *value) |
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{ |
{ |
int bits = BN_num_bits(value); |
int ret; |
int bin_size = (bits + 7) / 8; |
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u_char *buf = xmalloc(bin_size); |
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int oi; |
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char msg[2]; |
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/* Get the value of in binary */ |
if ((ret = sshbuf_get_u16(buffer, v)) != 0) { |
oi = BN_bn2bin(value, buf); |
error("%s: %s", __func__, ssh_err(ret)); |
if (oi != bin_size) |
return -1; |
fatal("buffer_put_bignum: BN_bn2bin() failed: oi %d != bin_size %d", |
} |
oi, bin_size); |
return 0; |
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/* Store the number of bits in the buffer in two bytes, msb first. */ |
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PUT_16BIT(msg, bits); |
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buffer_append(buffer, msg, 2); |
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/* Store the binary data. */ |
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buffer_append(buffer, (char *)buf, oi); |
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memset(buf, 0, bin_size); |
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xfree(buf); |
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} |
} |
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/* |
u_short |
* Retrieves an BIGNUM from the buffer. |
buffer_get_short(Buffer *buffer) |
*/ |
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void |
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buffer_get_bignum(Buffer *buffer, BIGNUM *value) |
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{ |
{ |
u_int bits, bytes; |
u_short ret; |
u_char buf[2], *bin; |
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/* Get the number for bits. */ |
if (buffer_get_short_ret(&ret, buffer) == -1) |
buffer_get(buffer, (char *) buf, 2); |
fatal("%s: buffer error", __func__); |
bits = GET_16BIT(buf); |
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/* Compute the number of binary bytes that follow. */ |
return (ret); |
bytes = (bits + 7) / 8; |
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if (bytes > 8 * 1024) |
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fatal("buffer_get_bignum: cannot handle BN of size %d", bytes); |
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if (buffer_len(buffer) < bytes) |
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fatal("buffer_get_bignum: input buffer too small"); |
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bin = buffer_ptr(buffer); |
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BN_bin2bn(bin, bytes, value); |
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buffer_consume(buffer, bytes); |
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} |
} |
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/* |
int |
* Stores an BIGNUM in the buffer in SSH2 format. |
buffer_get_int_ret(u_int *v, Buffer *buffer) |
*/ |
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void |
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buffer_put_bignum2(Buffer *buffer, BIGNUM *value) |
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{ |
{ |
u_int bytes = BN_num_bytes(value) + 1; |
int ret; |
u_char *buf = xmalloc(bytes); |
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int oi; |
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u_int hasnohigh = 0; |
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buf[0] = '\0'; |
if ((ret = sshbuf_get_u32(buffer, v)) != 0) { |
/* Get the value of in binary */ |
error("%s: %s", __func__, ssh_err(ret)); |
oi = BN_bn2bin(value, buf+1); |
return -1; |
if (oi != bytes-1) |
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fatal("buffer_put_bignum: BN_bn2bin() failed: oi %d != bin_size %d", |
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oi, bytes); |
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hasnohigh = (buf[1] & 0x80) ? 0 : 1; |
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if (value->neg) { |
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/**XXX should be two's-complement */ |
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int i, carry; |
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u_char *uc = buf; |
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logit("negativ!"); |
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for (i = bytes-1, carry = 1; i>=0; i--) { |
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uc[i] ^= 0xff; |
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if (carry) |
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carry = !++uc[i]; |
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} |
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} |
} |
buffer_put_string(buffer, buf+hasnohigh, bytes-hasnohigh); |
return 0; |
memset(buf, 0, bytes); |
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xfree(buf); |
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} |
} |
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/* XXX does not handle negative BNs */ |
u_int |
void |
buffer_get_int(Buffer *buffer) |
buffer_get_bignum2(Buffer *buffer, BIGNUM *value) |
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{ |
{ |
u_int len; |
u_int ret; |
u_char *bin = buffer_get_string(buffer, &len); |
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if (len > 8 * 1024) |
if (buffer_get_int_ret(&ret, buffer) == -1) |
fatal("buffer_get_bignum2: cannot handle BN of size %d", len); |
fatal("%s: buffer error", __func__); |
BN_bin2bn(bin, len, value); |
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xfree(bin); |
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} |
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/* |
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* Returns integers from the buffer (msb first). |
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*/ |
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u_short |
return (ret); |
buffer_get_short(Buffer *buffer) |
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{ |
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u_char buf[2]; |
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buffer_get(buffer, (char *) buf, 2); |
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return GET_16BIT(buf); |
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} |
} |
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u_int |
int |
buffer_get_int(Buffer *buffer) |
buffer_get_int64_ret(u_int64_t *v, Buffer *buffer) |
{ |
{ |
u_char buf[4]; |
int ret; |
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buffer_get(buffer, (char *) buf, 4); |
if ((ret = sshbuf_get_u64(buffer, v)) != 0) { |
return GET_32BIT(buf); |
error("%s: %s", __func__, ssh_err(ret)); |
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return -1; |
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} |
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return 0; |
} |
} |
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u_int64_t |
u_int64_t |
buffer_get_int64(Buffer *buffer) |
buffer_get_int64(Buffer *buffer) |
{ |
{ |
u_char buf[8]; |
u_int64_t ret; |
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buffer_get(buffer, (char *) buf, 8); |
if (buffer_get_int64_ret(&ret, buffer) == -1) |
return GET_64BIT(buf); |
fatal("%s: buffer error", __func__); |
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return (ret); |
} |
} |
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/* |
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* Stores integers in the buffer, msb first. |
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*/ |
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void |
void |
buffer_put_short(Buffer *buffer, u_short value) |
buffer_put_short(Buffer *buffer, u_short value) |
{ |
{ |
char buf[2]; |
int ret; |
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PUT_16BIT(buf, value); |
if ((ret = sshbuf_put_u16(buffer, value)) != 0) |
buffer_append(buffer, buf, 2); |
fatal("%s: %s", __func__, ssh_err(ret)); |
} |
} |
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void |
void |
buffer_put_int(Buffer *buffer, u_int value) |
buffer_put_int(Buffer *buffer, u_int value) |
{ |
{ |
char buf[4]; |
int ret; |
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PUT_32BIT(buf, value); |
if ((ret = sshbuf_put_u32(buffer, value)) != 0) |
buffer_append(buffer, buf, 4); |
fatal("%s: %s", __func__, ssh_err(ret)); |
} |
} |
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void |
void |
buffer_put_int64(Buffer *buffer, u_int64_t value) |
buffer_put_int64(Buffer *buffer, u_int64_t value) |
{ |
{ |
char buf[8]; |
int ret; |
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PUT_64BIT(buf, value); |
if ((ret = sshbuf_put_u64(buffer, value)) != 0) |
buffer_append(buffer, buf, 8); |
fatal("%s: %s", __func__, ssh_err(ret)); |
} |
} |
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/* |
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* Returns an arbitrary binary string from the buffer. The string cannot |
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* be longer than 256k. The returned value points to memory allocated |
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* with xmalloc; it is the responsibility of the calling function to free |
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* the data. If length_ptr is non-NULL, the length of the returned data |
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* will be stored there. A null character will be automatically appended |
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* to the returned string, and is not counted in length. |
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*/ |
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void * |
void * |
buffer_get_string(Buffer *buffer, u_int *length_ptr) |
buffer_get_string_ret(Buffer *buffer, u_int *length_ptr) |
{ |
{ |
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size_t len; |
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int ret; |
u_char *value; |
u_char *value; |
u_int len; |
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/* Get the length. */ |
if ((ret = sshbuf_get_string(buffer, &value, &len)) != 0) { |
len = buffer_get_int(buffer); |
error("%s: %s", __func__, ssh_err(ret)); |
if (len > 256 * 1024) |
return NULL; |
fatal("buffer_get_string: bad string length %u", len); |
} |
/* Allocate space for the string. Add one byte for a null character. */ |
if (length_ptr != NULL) |
value = xmalloc(len + 1); |
*length_ptr = len; /* Safe: sshbuf never stores len > 2^31 */ |
/* Get the string. */ |
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buffer_get(buffer, value, len); |
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/* Append a null character to make processing easier. */ |
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value[len] = 0; |
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/* Optionally return the length of the string. */ |
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if (length_ptr) |
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*length_ptr = len; |
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return value; |
return value; |
} |
} |
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/* |
void * |
* Stores and arbitrary binary string in the buffer. |
buffer_get_string(Buffer *buffer, u_int *length_ptr) |
*/ |
{ |
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void *ret; |
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if ((ret = buffer_get_string_ret(buffer, length_ptr)) == NULL) |
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fatal("%s: buffer error", __func__); |
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return (ret); |
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} |
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char * |
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buffer_get_cstring_ret(Buffer *buffer, u_int *length_ptr) |
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{ |
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size_t len; |
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int ret; |
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char *value; |
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if ((ret = sshbuf_get_cstring(buffer, &value, &len)) != 0) { |
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error("%s: %s", __func__, ssh_err(ret)); |
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return NULL; |
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} |
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if (length_ptr != NULL) |
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*length_ptr = len; /* Safe: sshbuf never stores len > 2^31 */ |
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return value; |
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} |
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char * |
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buffer_get_cstring(Buffer *buffer, u_int *length_ptr) |
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{ |
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char *ret; |
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if ((ret = buffer_get_cstring_ret(buffer, length_ptr)) == NULL) |
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fatal("%s: buffer error", __func__); |
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return ret; |
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} |
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const void * |
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buffer_get_string_ptr_ret(Buffer *buffer, u_int *length_ptr) |
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{ |
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size_t len; |
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int ret; |
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const u_char *value; |
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if ((ret = sshbuf_get_string_direct(buffer, &value, &len)) != 0) { |
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error("%s: %s", __func__, ssh_err(ret)); |
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return NULL; |
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} |
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if (length_ptr != NULL) |
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*length_ptr = len; /* Safe: sshbuf never stores len > 2^31 */ |
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return value; |
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} |
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const void * |
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buffer_get_string_ptr(Buffer *buffer, u_int *length_ptr) |
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{ |
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const void *ret; |
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if ((ret = buffer_get_string_ptr_ret(buffer, length_ptr)) == NULL) |
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fatal("%s: buffer error", __func__); |
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return (ret); |
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} |
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void |
void |
buffer_put_string(Buffer *buffer, const void *buf, u_int len) |
buffer_put_string(Buffer *buffer, const void *buf, u_int len) |
{ |
{ |
buffer_put_int(buffer, len); |
int ret; |
buffer_append(buffer, buf, len); |
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if ((ret = sshbuf_put_string(buffer, buf, len)) != 0) |
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fatal("%s: %s", __func__, ssh_err(ret)); |
} |
} |
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void |
void |
buffer_put_cstring(Buffer *buffer, const char *s) |
buffer_put_cstring(Buffer *buffer, const char *s) |
{ |
{ |
if (s == NULL) |
int ret; |
fatal("buffer_put_cstring: s == NULL"); |
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buffer_put_string(buffer, s, strlen(s)); |
if ((ret = sshbuf_put_cstring(buffer, s)) != 0) |
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fatal("%s: %s", __func__, ssh_err(ret)); |
} |
} |
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/* |
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* Returns a character from the buffer (0 - 255). |
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*/ |
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int |
int |
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buffer_get_char_ret(char *v, Buffer *buffer) |
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{ |
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int ret; |
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if ((ret = sshbuf_get_u8(buffer, (u_char *)v)) != 0) { |
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error("%s: %s", __func__, ssh_err(ret)); |
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return -1; |
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} |
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return 0; |
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} |
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int |
buffer_get_char(Buffer *buffer) |
buffer_get_char(Buffer *buffer) |
{ |
{ |
char ch; |
char ch; |
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buffer_get(buffer, &ch, 1); |
if (buffer_get_char_ret(&ch, buffer) == -1) |
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fatal("%s: buffer error", __func__); |
return (u_char) ch; |
return (u_char) ch; |
} |
} |
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/* |
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* Stores a character in the buffer. |
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*/ |
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void |
void |
buffer_put_char(Buffer *buffer, int value) |
buffer_put_char(Buffer *buffer, int value) |
{ |
{ |
char ch = value; |
int ret; |
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buffer_append(buffer, &ch, 1); |
if ((ret = sshbuf_put_u8(buffer, value)) != 0) |
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fatal("%s: %s", __func__, ssh_err(ret)); |
} |
} |
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void |
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buffer_put_bignum2_from_string(Buffer *buffer, const u_char *s, u_int l) |
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{ |
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int ret; |
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if ((ret = sshbuf_put_bignum2_bytes(buffer, s, l)) != 0) |
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fatal("%s: %s", __func__, ssh_err(ret)); |
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} |
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