Annotation of src/usr.bin/ssh/bufaux.c, Revision 1.50
1.50 ! djm 1: /* $OpenBSD: bufaux.c,v 1.49 2010/03/26 03:13:17 djm Exp $ */
1.1 deraadt 2: /*
1.6 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
1.13 deraadt 6: * Auxiliary functions for storing and retrieving various data types to/from
7: * Buffers.
1.11 markus 8: *
1.13 deraadt 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".
1.11 markus 14: *
1.6 deraadt 15: *
1.9 markus 16: * SSH2 packet format added by Markus Friedl
1.13 deraadt 17: * Copyright (c) 2000 Markus Friedl. All rights reserved.
1.9 markus 18: *
1.13 deraadt 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.
1.6 deraadt 38: */
1.1 deraadt 39:
1.44 deraadt 40: #include <sys/types.h>
1.1 deraadt 41:
1.10 markus 42: #include <openssl/bn.h>
1.43 stevesk 43:
44: #include <string.h>
1.44 deraadt 45: #include <stdarg.h>
1.43 stevesk 46:
1.1 deraadt 47: #include "xmalloc.h"
1.44 deraadt 48: #include "buffer.h"
1.17 markus 49: #include "log.h"
1.41 djm 50: #include "misc.h"
1.32 markus 51:
1.9 markus 52: /*
1.25 markus 53: * Returns integers from the buffer (msb first).
1.6 deraadt 54: */
1.25 markus 55:
1.33 djm 56: int
57: buffer_get_short_ret(u_short *ret, Buffer *buffer)
58: {
59: u_char buf[2];
60:
61: if (buffer_get_ret(buffer, (char *) buf, 2) == -1)
62: return (-1);
1.41 djm 63: *ret = get_u16(buf);
1.33 djm 64: return (0);
65: }
66:
1.25 markus 67: u_short
68: buffer_get_short(Buffer *buffer)
69: {
1.33 djm 70: u_short ret;
71:
72: if (buffer_get_short_ret(&ret, buffer) == -1)
73: fatal("buffer_get_short: buffer error");
74:
75: return (ret);
76: }
77:
78: int
79: buffer_get_int_ret(u_int *ret, Buffer *buffer)
80: {
81: u_char buf[4];
1.26 deraadt 82:
1.33 djm 83: if (buffer_get_ret(buffer, (char *) buf, 4) == -1)
84: return (-1);
1.49 djm 85: if (ret != NULL)
86: *ret = get_u32(buf);
1.33 djm 87: return (0);
1.25 markus 88: }
89:
1.14 markus 90: u_int
1.5 markus 91: buffer_get_int(Buffer *buffer)
1.1 deraadt 92: {
1.33 djm 93: u_int ret;
94:
95: if (buffer_get_int_ret(&ret, buffer) == -1)
96: fatal("buffer_get_int: buffer error");
97:
98: return (ret);
99: }
100:
101: int
102: buffer_get_int64_ret(u_int64_t *ret, Buffer *buffer)
103: {
104: u_char buf[8];
1.26 deraadt 105:
1.33 djm 106: if (buffer_get_ret(buffer, (char *) buf, 8) == -1)
107: return (-1);
1.49 djm 108: if (ret != NULL)
109: *ret = get_u64(buf);
1.33 djm 110: return (0);
1.1 deraadt 111: }
112:
1.15 markus 113: u_int64_t
114: buffer_get_int64(Buffer *buffer)
115: {
1.33 djm 116: u_int64_t ret;
117:
118: if (buffer_get_int64_ret(&ret, buffer) == -1)
119: fatal("buffer_get_int: buffer error");
1.26 deraadt 120:
1.33 djm 121: return (ret);
1.15 markus 122: }
123:
1.6 deraadt 124: /*
1.25 markus 125: * Stores integers in the buffer, msb first.
1.6 deraadt 126: */
1.25 markus 127: void
128: buffer_put_short(Buffer *buffer, u_short value)
129: {
130: char buf[2];
1.26 deraadt 131:
1.41 djm 132: put_u16(buf, value);
1.25 markus 133: buffer_append(buffer, buf, 2);
134: }
135:
1.11 markus 136: void
1.14 markus 137: buffer_put_int(Buffer *buffer, u_int value)
1.1 deraadt 138: {
1.5 markus 139: char buf[4];
1.26 deraadt 140:
1.41 djm 141: put_u32(buf, value);
1.5 markus 142: buffer_append(buffer, buf, 4);
1.15 markus 143: }
144:
145: void
146: buffer_put_int64(Buffer *buffer, u_int64_t value)
147: {
148: char buf[8];
1.26 deraadt 149:
1.41 djm 150: put_u64(buf, value);
1.15 markus 151: buffer_append(buffer, buf, 8);
1.1 deraadt 152: }
153:
1.6 deraadt 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: */
1.20 stevesk 162: void *
1.33 djm 163: buffer_get_string_ret(Buffer *buffer, u_int *length_ptr)
1.1 deraadt 164: {
1.26 deraadt 165: u_char *value;
1.14 markus 166: u_int len;
1.26 deraadt 167:
1.5 markus 168: /* Get the length. */
1.48 djm 169: if (buffer_get_int_ret(&len, buffer) != 0) {
170: error("buffer_get_string_ret: cannot extract length");
171: return (NULL);
172: }
1.33 djm 173: if (len > 256 * 1024) {
174: error("buffer_get_string_ret: bad string length %u", len);
175: return (NULL);
176: }
1.5 markus 177: /* Allocate space for the string. Add one byte for a null character. */
178: value = xmalloc(len + 1);
179: /* Get the string. */
1.33 djm 180: if (buffer_get_ret(buffer, value, len) == -1) {
181: error("buffer_get_string_ret: buffer_get failed");
182: xfree(value);
183: return (NULL);
184: }
1.5 markus 185: /* Append a null character to make processing easier. */
1.46 dtucker 186: value[len] = '\0';
1.5 markus 187: /* Optionally return the length of the string. */
188: if (length_ptr)
189: *length_ptr = len;
1.33 djm 190: return (value);
191: }
192:
193: void *
194: buffer_get_string(Buffer *buffer, u_int *length_ptr)
195: {
196: void *ret;
197:
198: if ((ret = buffer_get_string_ret(buffer, length_ptr)) == NULL)
199: fatal("buffer_get_string: buffer error");
200: return (ret);
1.50 ! djm 201: }
! 202:
! 203: char *
! 204: buffer_get_cstring_ret(Buffer *buffer, u_int *length_ptr)
! 205: {
! 206: u_int length;
! 207: char *cp, *ret = buffer_get_string_ret(buffer, &length);
! 208:
! 209: if (ret == NULL)
! 210: return NULL;
! 211: if ((cp = memchr(ret, '\0', length)) != NULL) {
! 212: /* XXX allow \0 at end-of-string for a while, remove later */
! 213: if (cp == ret + length - 1)
! 214: error("buffer_get_cstring_ret: string contains \\0");
! 215: else {
! 216: bzero(ret, length);
! 217: xfree(ret);
! 218: return NULL;
! 219: }
! 220: }
! 221: if (length_ptr != NULL)
! 222: *length_ptr = length;
! 223: return ret;
! 224: }
! 225:
! 226: char *
! 227: buffer_get_cstring(Buffer *buffer, u_int *length_ptr)
! 228: {
! 229: char *ret;
! 230:
! 231: if ((ret = buffer_get_cstring_ret(buffer, length_ptr)) == NULL)
! 232: fatal("buffer_get_cstring: buffer error");
! 233: return ret;
1.45 markus 234: }
235:
236: void *
1.47 djm 237: buffer_get_string_ptr_ret(Buffer *buffer, u_int *length_ptr)
1.45 markus 238: {
239: void *ptr;
240: u_int len;
241:
1.47 djm 242: if (buffer_get_int_ret(&len, buffer) != 0)
243: return NULL;
244: if (len > 256 * 1024) {
245: error("buffer_get_string_ptr: bad string length %u", len);
246: return NULL;
247: }
1.45 markus 248: ptr = buffer_ptr(buffer);
249: buffer_consume(buffer, len);
250: if (length_ptr)
251: *length_ptr = len;
252: return (ptr);
1.47 djm 253: }
254:
255: void *
256: buffer_get_string_ptr(Buffer *buffer, u_int *length_ptr)
257: {
258: void *ret;
259:
260: if ((ret = buffer_get_string_ptr_ret(buffer, length_ptr)) == NULL)
261: fatal("buffer_get_string_ptr: buffer error");
262: return (ret);
1.1 deraadt 263: }
264:
1.6 deraadt 265: /*
266: * Stores and arbitrary binary string in the buffer.
267: */
1.11 markus 268: void
1.14 markus 269: buffer_put_string(Buffer *buffer, const void *buf, u_int len)
1.1 deraadt 270: {
1.5 markus 271: buffer_put_int(buffer, len);
272: buffer_append(buffer, buf, len);
1.9 markus 273: }
1.11 markus 274: void
1.9 markus 275: buffer_put_cstring(Buffer *buffer, const char *s)
276: {
1.23 provos 277: if (s == NULL)
278: fatal("buffer_put_cstring: s == NULL");
1.9 markus 279: buffer_put_string(buffer, s, strlen(s));
1.1 deraadt 280: }
281:
1.6 deraadt 282: /*
283: * Returns a character from the buffer (0 - 255).
284: */
1.11 markus 285: int
1.33 djm 286: buffer_get_char_ret(char *ret, Buffer *buffer)
287: {
288: if (buffer_get_ret(buffer, ret, 1) == -1) {
289: error("buffer_get_char_ret: buffer_get_ret failed");
290: return (-1);
291: }
292: return (0);
293: }
294:
295: int
1.5 markus 296: buffer_get_char(Buffer *buffer)
1.1 deraadt 297: {
1.5 markus 298: char ch;
1.26 deraadt 299:
1.33 djm 300: if (buffer_get_char_ret(&ch, buffer) == -1)
301: fatal("buffer_get_char: buffer error");
1.14 markus 302: return (u_char) ch;
1.1 deraadt 303: }
304:
1.6 deraadt 305: /*
306: * Stores a character in the buffer.
307: */
1.11 markus 308: void
1.5 markus 309: buffer_put_char(Buffer *buffer, int value)
1.1 deraadt 310: {
1.5 markus 311: char ch = value;
1.26 deraadt 312:
1.5 markus 313: buffer_append(buffer, &ch, 1);
1.1 deraadt 314: }