src/crypto/axtls/bigint_impl.h

   1 /*
   2  *  Copyright(C) 2006 Cameron Rich
   3  *
   4  *  This library is free software; you can redistribute it and/or modify
   5  *  it under the terms of the GNU Lesser General Public License as published by
   6  *  the Free Software Foundation; either version 2.1 of the License, or
   7  *  (at your option) any later version.
   8  *
   9  *  This library is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *  GNU Lesser General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU Lesser General Public License
  15  *  along with this library; if not, write to the Free Software
  16  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  */
  18
  19 #ifndef BIGINT_IMPL_HEADER
  20 #define BIGINT_IMPL_HEADER
  21
  22 /* Maintain a number of precomputed variables when doing reduction */
  23 #define BIGINT_M_OFFSET     0    /**< Normal modulo offset. */
  24 #ifdef CONFIG_BIGINT_CRT
  25 #define BIGINT_P_OFFSET     1    /**< p modulo offset. */
  26 #define BIGINT_Q_OFFSET     2    /**< q module offset. */
  27 #define BIGINT_NUM_MODS     3    /**< The number of modulus constants used. */
  28 #else
  29 #define BIGINT_NUM_MODS     1
  30 #endif
  31
  32 /* Architecture specific functions for big ints */
  33 #ifdef WIN32
  34 #define COMP_RADIX          4294967296i64
  35 #define COMP_BIG_MSB        0x8000000000000000i64
  36 #else
  37 #define COMP_RADIX          4294967296ULL         /**< Max component + 1 */
  38 #define COMP_BIG_MSB        0x8000000000000000ULL /**< (Max dbl comp + 1)/ 2 */
  39 #endif
  40 #define COMP_BIT_SIZE       32  /**< Number of bits in a component. */
  41 #define COMP_BYTE_SIZE      4   /**< Number of bytes in a component. */
  42 #define COMP_NUM_NIBBLES    8   /**< Used For diagnostics only. */
  43
  44 typedef uint32_t comp;          /**< A single precision component. */
  45 typedef uint64_t long_comp;     /**< A double precision component. */
  46 typedef int64_t slong_comp;     /**< A signed double precision component. */
  47
  48 /**
  49  * @struct  _bigint
  50  * @brief A big integer basic object
  51  */
  52 struct _bigint
  53 {
  54     struct _bigint* next;       /**< The next bigint in the cache. */
  55     short size;                 /**< The number of components in this bigint. */
  56     short max_comps;            /**< The heapsize allocated for this bigint */
  57     int refs;                   /**< An internal reference count. */
  58     comp* comps;                /**< A ptr to the actual component data */
  59 };
  60
  61 typedef struct _bigint bigint;  /**< An alias for _bigint */
  62
  63 /**
  64  * Maintains the state of the cache, and a number of variables used in
  65  * reduction.
  66  */
  67 typedef struct /**< A big integer "session" context. */
  68 {
  69     bigint *active_list;                    /**< Bigints currently used. */
  70     bigint *free_list;                      /**< Bigints not used. */
  71     bigint *bi_radix;                       /**< The radix used. */
  72     bigint *bi_mod[BIGINT_NUM_MODS];        /**< modulus */
  73
  74 #if defined(CONFIG_BIGINT_MONTGOMERY)
  75     bigint *bi_RR_mod_m[BIGINT_NUM_MODS];   /**< R^2 mod m */
  76     bigint *bi_R_mod_m[BIGINT_NUM_MODS];    /**< R mod m */
  77     comp N0_dash[BIGINT_NUM_MODS];
  78 #elif defined(CONFIG_BIGINT_BARRETT)
  79     bigint *bi_mu[BIGINT_NUM_MODS];         /**< Storage for mu */
  80 #endif
  81     bigint *bi_normalised_mod[BIGINT_NUM_MODS]; /**< Normalised mod storage. */
  82     bigint **g;                 /**< Used by sliding-window. */
  83     int window;                 /**< The size of the sliding window */
  84     int active_count;           /**< Number of active bigints. */
  85     int free_count;             /**< Number of free bigints. */
  86
  87 #ifdef CONFIG_BIGINT_MONTGOMERY
  88     uint8_t use_classical;      /**< Use classical reduction. */
  89 #endif
  90     uint8_t mod_offset;         /**< The mod offset we are using */
  91 } BI_CTX;
  92
  93 #ifndef WIN32
  94 #define max(a,b) ((a)>(b)?(a):(b))  /**< Find the maximum of 2 numbers. */
  95 #define min(a,b) ((a)<(b)?(a):(b))  /**< Find the minimum of 2 numbers. */
  96 #endif
  97
  98 #define PERMANENT           0x7FFF55AA  /**< A magic number for permanents. */
  99
 100 #define V1      v->comps[v->size-1]                 /**< v1 for division */
 101 #define V2      v->comps[v->size-2]                 /**< v2 for division */
 102 #define U(j)    tmp_u->comps[tmp_u->size-j-1]       /**< uj for division */
 103 #define Q(j)    quotient->comps[quotient->size-j-1] /**< qj for division */
 104
 105 #endif