=================================================================== RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/Attic/bufaux.c,v retrieving revision 1.1 retrieving revision 1.56.4.1 diff -u -r1.1 -r1.56.4.1 --- src/usr.bin/ssh/Attic/bufaux.c 1999/09/26 20:53:33 1.1 +++ src/usr.bin/ssh/Attic/bufaux.c 2014/04/21 00:30:48 1.56.4.1 @@ -1,170 +1,391 @@ +/* $OpenBSD: bufaux.c,v 1.56.4.1 2014/04/21 00:30:48 djm Exp $ */ /* + * Author: Tatu Ylonen + * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland + * All rights reserved + * Auxiliary functions for storing and retrieving various data types to/from + * Buffers. + * + * As far as I am concerned, the code I have written for this software + * can be used freely for any purpose. Any derived versions of this + * software must be clearly marked as such, and if the derived work is + * incompatible with the protocol description in the RFC file, it must be + * called by a name other than "ssh" or "Secure Shell". + * + * + * SSH2 packet format added by Markus Friedl + * Copyright (c) 2000 Markus Friedl. 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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. + */ -bufaux.c +#include -Author: Tatu Ylonen +#include -Copyright (c) 1995 Tatu Ylonen , Espoo, Finland - All rights reserved +#include +#include +#include -Created: Wed Mar 29 02:24:47 1995 ylo +#include "xmalloc.h" +#include "buffer.h" +#include "log.h" +#include "misc.h" -Auxiliary functions for storing and retrieving various data types to/from -Buffers. +/* + * Returns integers from the buffer (msb first). + */ -*/ +int +buffer_get_short_ret(u_short *ret, Buffer *buffer) +{ + u_char buf[2]; -#include "includes.h" -RCSID("$Id: bufaux.c,v 1.1 1999/09/26 20:53:33 deraadt Exp $"); + if (buffer_get_ret(buffer, (char *) buf, 2) == -1) + return (-1); + *ret = get_u16(buf); + return (0); +} -#include "ssh.h" -#include "gmp.h" -#include "bufaux.h" -#include "xmalloc.h" -#include "getput.h" +u_short +buffer_get_short(Buffer *buffer) +{ + u_short ret; -/* Stores an MP_INT in the buffer with a 2-byte msb first bit count, followed - by (bits+7)/8 bytes of binary data, msb first. */ + if (buffer_get_short_ret(&ret, buffer) == -1) + fatal("buffer_get_short: buffer error"); -void buffer_put_mp_int(Buffer *buffer, MP_INT *value) + return (ret); +} + +int +buffer_get_int_ret(u_int *ret, Buffer *buffer) { - int bits = mpz_sizeinbase(value, 2); - int hex_size = mpz_sizeinbase(value, 16); - char *buf = xmalloc(hex_size + 2); - int i, oi, byte; - char msg[2]; - - /* Get the value of the number in hex. Too bad that gmp does not allow - us to get it in binary. */ - mpz_get_str(buf, 16, value); + u_char buf[4]; - /* i is "input index", oi is "output index". Both point to the same array, - and start from the beginning. "input index" moves twice as fast. */ - i = 0; - oi = 0; - /* Check for an odd number of hex digits. Process the odd digit - separately. */ - if (hex_size & 1) - { - sscanf(buf, "%1x", &byte); - buf[oi++] = byte; - i = 1; - } + if (buffer_get_ret(buffer, (char *) buf, 4) == -1) + return (-1); + if (ret != NULL) + *ret = get_u32(buf); + return (0); +} - /* Convert the hex number into binary representation. */ - for (; i < hex_size; i += 2) - { - sscanf(buf + i, "%2x", &byte); - buf[oi++] = byte; - } - - assert(oi == ((bits + 7) / 8)); - /* Store the number of bits in the buffer in two bytes, msb first. */ - PUT_16BIT(msg, bits); - buffer_append(buffer, msg, 2); - /* Store the binary data. */ - buffer_append(buffer, buf, oi); - /* Clear the temporary data. */ - memset(buf, 0, hex_size); - xfree(buf); +u_int +buffer_get_int(Buffer *buffer) +{ + u_int ret; + + if (buffer_get_int_ret(&ret, buffer) == -1) + fatal("buffer_get_int: buffer error"); + + return (ret); } -/* Retrieves an MP_INT from the buffer. */ +int +buffer_get_int64_ret(u_int64_t *ret, Buffer *buffer) +{ + u_char buf[8]; -int buffer_get_mp_int(Buffer *buffer, MP_INT *value) + if (buffer_get_ret(buffer, (char *) buf, 8) == -1) + return (-1); + if (ret != NULL) + *ret = get_u64(buf); + return (0); +} + +u_int64_t +buffer_get_int64(Buffer *buffer) { - int i, bits, bytes; - char *hex; - unsigned char buf[2]; + u_int64_t ret; - /* Get the number for bits. */ - buffer_get(buffer, (char *)buf, 2); - bits = GET_16BIT(buf); - /* Compute the number of binary bytes that follow. */ - bytes = (bits + 7) / 8; - /* Allocate space for a corresponding hex string. */ - hex = xmalloc(2 * bytes + 1); - - /* Read and convert the binary bytes into a hex string. */ - for (i = 0; i < bytes; i++) - { - unsigned char byte; - buffer_get(buffer, (char *)&byte, 1); - sprintf(hex + 2 * i, "%02x", byte); - } - /* Read the hex string into a mp-int. */ - mpz_set_str(value, hex, 16); - /* Free the string. */ - xfree(hex); - return 2 + bytes; + if (buffer_get_int64_ret(&ret, buffer) == -1) + fatal("buffer_get_int: buffer error"); + + return (ret); } -/* Returns an integer from the buffer (4 bytes, msb first). */ +/* + * Stores integers in the buffer, msb first. + */ +void +buffer_put_short(Buffer *buffer, u_short value) +{ + char buf[2]; -unsigned int buffer_get_int(Buffer *buffer) + put_u16(buf, value); + buffer_append(buffer, buf, 2); +} + +void +buffer_put_int(Buffer *buffer, u_int value) { - unsigned char buf[4]; - buffer_get(buffer, (char *)buf, 4); - return GET_32BIT(buf); + char buf[4]; + + put_u32(buf, value); + buffer_append(buffer, buf, 4); } -/* Stores an integer in the buffer in 4 bytes, msb first. */ +void +buffer_put_int64(Buffer *buffer, u_int64_t value) +{ + char buf[8]; -void buffer_put_int(Buffer *buffer, unsigned int value) + put_u64(buf, value); + buffer_append(buffer, buf, 8); +} + +/* + * Returns an arbitrary binary string from the buffer. The string cannot + * be longer than 256k. The returned value points to memory allocated + * with xmalloc; it is the responsibility of the calling function to free + * the data. If length_ptr is non-NULL, the length of the returned data + * will be stored there. A null character will be automatically appended + * to the returned string, and is not counted in length. + */ +void * +buffer_get_string_ret(Buffer *buffer, u_int *length_ptr) { - char buf[4]; - PUT_32BIT(buf, value); - buffer_append(buffer, buf, 4); + u_char *value; + u_int len; + + /* Get the length. */ + if (buffer_get_int_ret(&len, buffer) != 0) { + error("buffer_get_string_ret: cannot extract length"); + return (NULL); + } + if (len > 256 * 1024) { + error("buffer_get_string_ret: bad string length %u", len); + return (NULL); + } + /* Allocate space for the string. Add one byte for a null character. */ + value = xmalloc(len + 1); + /* Get the string. */ + if (buffer_get_ret(buffer, value, len) == -1) { + error("buffer_get_string_ret: buffer_get failed"); + free(value); + return (NULL); + } + /* Append a null character to make processing easier. */ + value[len] = '\0'; + /* Optionally return the length of the string. */ + if (length_ptr) + *length_ptr = len; + return (value); } -/* Returns an arbitrary binary string from the buffer. The string cannot - be longer than 256k. The returned value points to memory allocated - with xmalloc; it is the responsibility of the calling function to free - the data. If length_ptr is non-NULL, the length of the returned data - will be stored there. A null character will be automatically appended - to the returned string, and is not counted in length. */ +void * +buffer_get_string(Buffer *buffer, u_int *length_ptr) +{ + void *ret; -char *buffer_get_string(Buffer *buffer, unsigned int *length_ptr) + if ((ret = buffer_get_string_ret(buffer, length_ptr)) == NULL) + fatal("buffer_get_string: buffer error"); + return (ret); +} + +char * +buffer_get_cstring_ret(Buffer *buffer, u_int *length_ptr) { - unsigned int len; - char *value; - /* Get the length. */ - len = buffer_get_int(buffer); - if (len > 256*1024) - fatal("Received packet with bad string length %d", len); - /* Allocate space for the string. Add one byte for a null character. */ - value = xmalloc(len + 1); - /* Get the string. */ - buffer_get(buffer, value, len); - /* Append a null character to make processing easier. */ - value[len] = 0; - /* Optionally return the length of the string. */ - if (length_ptr) - *length_ptr = len; - return value; + u_int length; + char *cp, *ret = buffer_get_string_ret(buffer, &length); + + if (ret == NULL) + return NULL; + if ((cp = memchr(ret, '\0', length)) != NULL) { + /* XXX allow \0 at end-of-string for a while, remove later */ + if (cp == ret + length - 1) + error("buffer_get_cstring_ret: string contains \\0"); + else { + explicit_bzero(ret, length); + free(ret); + return NULL; + } + } + if (length_ptr != NULL) + *length_ptr = length; + return ret; } -/* Stores and arbitrary binary string in the buffer. */ +char * +buffer_get_cstring(Buffer *buffer, u_int *length_ptr) +{ + char *ret; -void buffer_put_string(Buffer *buffer, const void *buf, unsigned int len) + if ((ret = buffer_get_cstring_ret(buffer, length_ptr)) == NULL) + fatal("buffer_get_cstring: buffer error"); + return ret; +} + +void * +buffer_get_string_ptr_ret(Buffer *buffer, u_int *length_ptr) { - buffer_put_int(buffer, len); - buffer_append(buffer, buf, len); + void *ptr; + u_int len; + + if (buffer_get_int_ret(&len, buffer) != 0) + return NULL; + if (len > 256 * 1024) { + error("buffer_get_string_ptr: bad string length %u", len); + return NULL; + } + ptr = buffer_ptr(buffer); + buffer_consume(buffer, len); + if (length_ptr) + *length_ptr = len; + return (ptr); } -/* Returns a character from the buffer (0 - 255). */ +void * +buffer_get_string_ptr(Buffer *buffer, u_int *length_ptr) +{ + void *ret; -int buffer_get_char(Buffer *buffer) + if ((ret = buffer_get_string_ptr_ret(buffer, length_ptr)) == NULL) + fatal("buffer_get_string_ptr: buffer error"); + return (ret); +} + +/* + * Stores and arbitrary binary string in the buffer. + */ +void +buffer_put_string(Buffer *buffer, const void *buf, u_int len) { - char ch; - buffer_get(buffer, &ch, 1); - return (unsigned char)ch; + buffer_put_int(buffer, len); + buffer_append(buffer, buf, len); } +void +buffer_put_cstring(Buffer *buffer, const char *s) +{ + if (s == NULL) + fatal("buffer_put_cstring: s == NULL"); + buffer_put_string(buffer, s, strlen(s)); +} -/* Stores a character in the buffer. */ +/* + * Returns a character from the buffer (0 - 255). + */ +int +buffer_get_char_ret(u_char *ret, Buffer *buffer) +{ + if (buffer_get_ret(buffer, ret, 1) == -1) { + error("buffer_get_char_ret: buffer_get_ret failed"); + return (-1); + } + return (0); +} -void buffer_put_char(Buffer *buffer, int value) +int +buffer_get_char(Buffer *buffer) { - char ch = value; - buffer_append(buffer, &ch, 1); + u_char ch; + + if (buffer_get_char_ret(&ch, buffer) == -1) + fatal("buffer_get_char: buffer error"); + return ch; } + +/* + * Stores a character in the buffer. + */ +void +buffer_put_char(Buffer *buffer, int value) +{ + char ch = value; + + buffer_append(buffer, &ch, 1); +} + +/* Pseudo bignum functions */ + +void * +buffer_get_bignum2_as_string_ret(Buffer *buffer, u_int *length_ptr) +{ + u_int len; + u_char *bin, *p, *ret; + + if ((p = bin = buffer_get_string_ret(buffer, &len)) == NULL) { + error("%s: invalid bignum", __func__); + return NULL; + } + + if (len > 0 && (bin[0] & 0x80)) { + error("%s: negative numbers not supported", __func__); + free(bin); + return NULL; + } + if (len > 8 * 1024) { + error("%s: cannot handle BN of size %d", __func__, len); + free(bin); + return NULL; + } + /* Skip zero prefix on numbers with the MSB set */ + if (len > 1 && bin[0] == 0x00 && (bin[1] & 0x80) != 0) { + p++; + len--; + } + ret = xmalloc(len); + memcpy(ret, p, len); + explicit_bzero(p, len); + free(bin); + return ret; +} + +void * +buffer_get_bignum2_as_string(Buffer *buffer, u_int *l) +{ + void *ret = buffer_get_bignum2_as_string_ret(buffer, l); + + if (ret == NULL) + fatal("%s: buffer error", __func__); + return ret; +} + +/* + * Stores a string using the bignum encoding rules (\0 pad if MSB set). + */ +void +buffer_put_bignum2_from_string(Buffer *buffer, const u_char *s, u_int l) +{ + u_char *buf, *p; + int pad = 0; + + if (l > 8 * 1024) + fatal("%s: length %u too long", __func__, l); + /* Skip leading zero bytes */ + for (; l > 0 && *s == 0; l--, s++) + ; + p = buf = xmalloc(l + 1); + /* + * If most significant bit is set then prepend a zero byte to + * avoid interpretation as a negative number. + */ + if (l > 0 && (s[0] & 0x80) != 0) { + *p++ = '\0'; + pad = 1; + } + memcpy(p, s, l); + buffer_put_string(buffer, buf, l + pad); + explicit_bzero(buf, l + pad); + free(buf); +} + +