release/src/router/dropbear/bignum.c

   1 /*
   2  * Dropbear - a SSH2 server
   3  *
   4  * Copyright (c) 2002,2003 Matt Johnston
   5  * All rights reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23  * SOFTWARE. */
  24
  25 /* Contains helper functions for mp_int handling */
  26
  27 #include "includes.h"
  28 #include "dbutil.h"
  29
  30 /* wrapper for mp_init, failing fatally on errors (memory allocation) */
  31 void m_mp_init(mp_int *mp) {
  32
  33         if (mp_init(mp) != MP_OKAY) {
  34                 dropbear_exit("Mem alloc error");
  35         }
  36 }
  37
  38 /* simplified duplication of bn_mp_multi's mp_init_multi, but die fatally
  39  * on error */
  40 void m_mp_init_multi(mp_int *mp, ...)
  41 {
  42     mp_int* cur_arg = mp;
  43     va_list args;
  44
  45     va_start(args, mp);        /* init args to next argument from caller */
  46     while (cur_arg != NULL) {
  47         if (mp_init(cur_arg) != MP_OKAY) {
  48                         dropbear_exit("Mem alloc error");
  49         }
  50         cur_arg = va_arg(args, mp_int*);
  51     }
  52     va_end(args);
  53 }
  54
  55 void bytes_to_mp(mp_int *mp, const unsigned char* bytes, unsigned int len) {
  56
  57         if (mp_read_unsigned_bin(mp, (unsigned char*)bytes, len) != MP_OKAY) {
  58                 dropbear_exit("Mem alloc error");
  59         }
  60 }
  61
  62 /* hash the ssh representation of the mp_int mp */
  63 void sha1_process_mp(hash_state *hs, mp_int *mp) {
  64
  65         int i;
  66         buffer * buf;
  67
  68         buf = buf_new(512 + 20); /* max buffer is a 4096 bit key,
  69                                                                 plus header + some leeway*/
  70         buf_putmpint(buf, mp);
  71         i = buf->pos;
  72         buf_setpos(buf, 0);
  73         sha1_process(hs, buf_getptr(buf, i), i);
  74         buf_free(buf);
  75 }