Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 1 | /* $OpenBSD: bufaux.c,v 1.44 2006/08/03 03:34:41 deraadt Exp $ */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 2 | /* |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 3 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 4 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
| 5 | * All rights reserved |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 6 | * Auxiliary functions for storing and retrieving various data types to/from |
| 7 | * Buffers. |
| 8 | * |
Damien Miller | e4340be | 2000-09-16 13:29:08 +1100 | [diff] [blame] | 9 | * As far as I am concerned, the code I have written for this software |
| 10 | * can be used freely for any purpose. Any derived versions of this |
| 11 | * software must be clearly marked as such, and if the derived work is |
| 12 | * incompatible with the protocol description in the RFC file, it must be |
| 13 | * called by a name other than "ssh" or "Secure Shell". |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 14 | * |
Damien Miller | e4340be | 2000-09-16 13:29:08 +1100 | [diff] [blame] | 15 | * |
| 16 | * SSH2 packet format added by Markus Friedl |
| 17 | * Copyright (c) 2000 Markus Friedl. All rights reserved. |
| 18 | * |
| 19 | * Redistribution and use in source and binary forms, with or without |
| 20 | * modification, are permitted provided that the following conditions |
| 21 | * are met: |
| 22 | * 1. Redistributions of source code must retain the above copyright |
| 23 | * notice, this list of conditions and the following disclaimer. |
| 24 | * 2. Redistributions in binary form must reproduce the above copyright |
| 25 | * notice, this list of conditions and the following disclaimer in the |
| 26 | * documentation and/or other materials provided with the distribution. |
| 27 | * |
| 28 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 29 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 30 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 31 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 32 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 33 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 34 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 35 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 36 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 37 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 38 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 39 | |
| 40 | #include "includes.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 41 | |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 42 | #include <sys/types.h> |
| 43 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 44 | #include <openssl/bn.h> |
Damien Miller | e3476ed | 2006-07-24 14:13:33 +1000 | [diff] [blame] | 45 | |
| 46 | #include <string.h> |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 47 | #include <stdarg.h> |
Damien Miller | e3476ed | 2006-07-24 14:13:33 +1000 | [diff] [blame] | 48 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 49 | #include "xmalloc.h" |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 50 | #include "buffer.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 51 | #include "log.h" |
Damien Miller | 3f94188 | 2006-03-31 23:13:02 +1100 | [diff] [blame] | 52 | #include "misc.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 53 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 54 | /* |
Damien Miller | 3b23566 | 2002-04-23 20:42:36 +1000 | [diff] [blame] | 55 | * Returns integers from the buffer (msb first). |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 56 | */ |
Damien Miller | 3b23566 | 2002-04-23 20:42:36 +1000 | [diff] [blame] | 57 | |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 58 | int |
| 59 | buffer_get_short_ret(u_short *ret, Buffer *buffer) |
Damien Miller | 3b23566 | 2002-04-23 20:42:36 +1000 | [diff] [blame] | 60 | { |
| 61 | u_char buf[2]; |
Ben Lindstrom | e135363 | 2002-06-23 21:29:23 +0000 | [diff] [blame] | 62 | |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 63 | if (buffer_get_ret(buffer, (char *) buf, 2) == -1) |
| 64 | return (-1); |
Damien Miller | 3f94188 | 2006-03-31 23:13:02 +1100 | [diff] [blame] | 65 | *ret = get_u16(buf); |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 66 | return (0); |
| 67 | } |
| 68 | |
| 69 | u_short |
| 70 | buffer_get_short(Buffer *buffer) |
| 71 | { |
| 72 | u_short ret; |
| 73 | |
| 74 | if (buffer_get_short_ret(&ret, buffer) == -1) |
| 75 | fatal("buffer_get_short: buffer error"); |
| 76 | |
| 77 | return (ret); |
| 78 | } |
| 79 | |
| 80 | int |
| 81 | buffer_get_int_ret(u_int *ret, Buffer *buffer) |
| 82 | { |
| 83 | u_char buf[4]; |
| 84 | |
| 85 | if (buffer_get_ret(buffer, (char *) buf, 4) == -1) |
| 86 | return (-1); |
Damien Miller | 3f94188 | 2006-03-31 23:13:02 +1100 | [diff] [blame] | 87 | *ret = get_u32(buf); |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 88 | return (0); |
Damien Miller | 3b23566 | 2002-04-23 20:42:36 +1000 | [diff] [blame] | 89 | } |
| 90 | |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 91 | u_int |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 92 | buffer_get_int(Buffer *buffer) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 93 | { |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 94 | u_int ret; |
Ben Lindstrom | e135363 | 2002-06-23 21:29:23 +0000 | [diff] [blame] | 95 | |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 96 | if (buffer_get_int_ret(&ret, buffer) == -1) |
| 97 | fatal("buffer_get_int: buffer error"); |
| 98 | |
| 99 | return (ret); |
| 100 | } |
| 101 | |
| 102 | int |
| 103 | buffer_get_int64_ret(u_int64_t *ret, Buffer *buffer) |
| 104 | { |
| 105 | u_char buf[8]; |
| 106 | |
| 107 | if (buffer_get_ret(buffer, (char *) buf, 8) == -1) |
| 108 | return (-1); |
Damien Miller | 3f94188 | 2006-03-31 23:13:02 +1100 | [diff] [blame] | 109 | *ret = get_u64(buf); |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 110 | return (0); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 111 | } |
| 112 | |
Ben Lindstrom | 2f959b4 | 2001-01-11 06:20:23 +0000 | [diff] [blame] | 113 | u_int64_t |
| 114 | buffer_get_int64(Buffer *buffer) |
| 115 | { |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 116 | u_int64_t ret; |
Ben Lindstrom | e135363 | 2002-06-23 21:29:23 +0000 | [diff] [blame] | 117 | |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 118 | if (buffer_get_int64_ret(&ret, buffer) == -1) |
| 119 | fatal("buffer_get_int: buffer error"); |
| 120 | |
| 121 | return (ret); |
Ben Lindstrom | 2f959b4 | 2001-01-11 06:20:23 +0000 | [diff] [blame] | 122 | } |
| 123 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 124 | /* |
Damien Miller | 3b23566 | 2002-04-23 20:42:36 +1000 | [diff] [blame] | 125 | * Stores integers in the buffer, msb first. |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 126 | */ |
Damien Miller | 5f05637 | 2000-04-16 12:31:48 +1000 | [diff] [blame] | 127 | void |
Damien Miller | 3b23566 | 2002-04-23 20:42:36 +1000 | [diff] [blame] | 128 | buffer_put_short(Buffer *buffer, u_short value) |
| 129 | { |
| 130 | char buf[2]; |
Ben Lindstrom | e135363 | 2002-06-23 21:29:23 +0000 | [diff] [blame] | 131 | |
Damien Miller | 3f94188 | 2006-03-31 23:13:02 +1100 | [diff] [blame] | 132 | put_u16(buf, value); |
Damien Miller | 3b23566 | 2002-04-23 20:42:36 +1000 | [diff] [blame] | 133 | buffer_append(buffer, buf, 2); |
| 134 | } |
| 135 | |
| 136 | void |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 137 | buffer_put_int(Buffer *buffer, u_int value) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 138 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 139 | char buf[4]; |
Ben Lindstrom | e135363 | 2002-06-23 21:29:23 +0000 | [diff] [blame] | 140 | |
Damien Miller | 3f94188 | 2006-03-31 23:13:02 +1100 | [diff] [blame] | 141 | put_u32(buf, value); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 142 | buffer_append(buffer, buf, 4); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 143 | } |
| 144 | |
Ben Lindstrom | 2f959b4 | 2001-01-11 06:20:23 +0000 | [diff] [blame] | 145 | void |
| 146 | buffer_put_int64(Buffer *buffer, u_int64_t value) |
| 147 | { |
| 148 | char buf[8]; |
Ben Lindstrom | e135363 | 2002-06-23 21:29:23 +0000 | [diff] [blame] | 149 | |
Damien Miller | 3f94188 | 2006-03-31 23:13:02 +1100 | [diff] [blame] | 150 | put_u64(buf, value); |
Ben Lindstrom | 2f959b4 | 2001-01-11 06:20:23 +0000 | [diff] [blame] | 151 | buffer_append(buffer, buf, 8); |
| 152 | } |
| 153 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 154 | /* |
| 155 | * Returns an arbitrary binary string from the buffer. The string cannot |
| 156 | * be longer than 256k. The returned value points to memory allocated |
| 157 | * with xmalloc; it is the responsibility of the calling function to free |
| 158 | * the data. If length_ptr is non-NULL, the length of the returned data |
| 159 | * will be stored there. A null character will be automatically appended |
| 160 | * to the returned string, and is not counted in length. |
| 161 | */ |
Damien Miller | 5a6b4fe | 2001-12-21 14:56:54 +1100 | [diff] [blame] | 162 | void * |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 163 | buffer_get_string_ret(Buffer *buffer, u_int *length_ptr) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 164 | { |
Damien Miller | 5a6b4fe | 2001-12-21 14:56:54 +1100 | [diff] [blame] | 165 | u_char *value; |
Ben Lindstrom | e135363 | 2002-06-23 21:29:23 +0000 | [diff] [blame] | 166 | u_int len; |
| 167 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 168 | /* Get the length. */ |
| 169 | len = buffer_get_int(buffer); |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 170 | if (len > 256 * 1024) { |
| 171 | error("buffer_get_string_ret: bad string length %u", len); |
| 172 | return (NULL); |
| 173 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 174 | /* Allocate space for the string. Add one byte for a null character. */ |
| 175 | value = xmalloc(len + 1); |
| 176 | /* Get the string. */ |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 177 | if (buffer_get_ret(buffer, value, len) == -1) { |
| 178 | error("buffer_get_string_ret: buffer_get failed"); |
| 179 | xfree(value); |
| 180 | return (NULL); |
| 181 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 182 | /* Append a null character to make processing easier. */ |
| 183 | value[len] = 0; |
| 184 | /* Optionally return the length of the string. */ |
| 185 | if (length_ptr) |
| 186 | *length_ptr = len; |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 187 | return (value); |
| 188 | } |
| 189 | |
| 190 | void * |
| 191 | buffer_get_string(Buffer *buffer, u_int *length_ptr) |
| 192 | { |
| 193 | void *ret; |
| 194 | |
| 195 | if ((ret = buffer_get_string_ret(buffer, length_ptr)) == NULL) |
| 196 | fatal("buffer_get_string: buffer error"); |
| 197 | return (ret); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 198 | } |
| 199 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 200 | /* |
| 201 | * Stores and arbitrary binary string in the buffer. |
| 202 | */ |
Damien Miller | 5f05637 | 2000-04-16 12:31:48 +1000 | [diff] [blame] | 203 | void |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 204 | buffer_put_string(Buffer *buffer, const void *buf, u_int len) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 205 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 206 | buffer_put_int(buffer, len); |
| 207 | buffer_append(buffer, buf, len); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 208 | } |
Damien Miller | 5f05637 | 2000-04-16 12:31:48 +1000 | [diff] [blame] | 209 | void |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 210 | buffer_put_cstring(Buffer *buffer, const char *s) |
| 211 | { |
Ben Lindstrom | 88aa1b4 | 2002-03-22 01:47:52 +0000 | [diff] [blame] | 212 | if (s == NULL) |
| 213 | fatal("buffer_put_cstring: s == NULL"); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 214 | buffer_put_string(buffer, s, strlen(s)); |
| 215 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 216 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 217 | /* |
| 218 | * Returns a character from the buffer (0 - 255). |
| 219 | */ |
Damien Miller | 5f05637 | 2000-04-16 12:31:48 +1000 | [diff] [blame] | 220 | int |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 221 | buffer_get_char_ret(char *ret, Buffer *buffer) |
| 222 | { |
| 223 | if (buffer_get_ret(buffer, ret, 1) == -1) { |
| 224 | error("buffer_get_char_ret: buffer_get_ret failed"); |
| 225 | return (-1); |
| 226 | } |
| 227 | return (0); |
| 228 | } |
| 229 | |
| 230 | int |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 231 | buffer_get_char(Buffer *buffer) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 232 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 233 | char ch; |
Ben Lindstrom | e135363 | 2002-06-23 21:29:23 +0000 | [diff] [blame] | 234 | |
Darren Tucker | 50dbe83 | 2004-11-05 20:41:24 +1100 | [diff] [blame] | 235 | if (buffer_get_char_ret(&ch, buffer) == -1) |
| 236 | fatal("buffer_get_char: buffer error"); |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 237 | return (u_char) ch; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 238 | } |
| 239 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 240 | /* |
| 241 | * Stores a character in the buffer. |
| 242 | */ |
Damien Miller | 5f05637 | 2000-04-16 12:31:48 +1000 | [diff] [blame] | 243 | void |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 244 | buffer_put_char(Buffer *buffer, int value) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 245 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 246 | char ch = value; |
Ben Lindstrom | e135363 | 2002-06-23 21:29:23 +0000 | [diff] [blame] | 247 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 248 | buffer_append(buffer, &ch, 1); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 249 | } |