view libtomcrypt/src/math/tfm_desc.c @ 1156:a8f4dade70e5

avoid getpass when not used some systems (like android's bionic) do not provide getpass. you can disable ENABLE_CLI_PASSWORD_AUTH & ENABLE_CLI_INTERACT_AUTH to avoid its use (and rely on pubkey auth), but the link still fails because the support file calls getpass. do not define this func if both of those auth methods are not used.
author Mike Frysinger <vapier@gentoo.org>
date Wed, 21 Oct 2015 22:39:55 +0800
parents 0cbe8f6dbf9e
children f849a5ca2efc
line wrap: on
line source

/* LibTomCrypt, modular cryptographic library -- Tom St Denis
 *
 * LibTomCrypt is a library that provides various cryptographic
 * algorithms in a highly modular and flexible manner.
 *
 * The library is free for all purposes without any express
 * guarantee it works.
 *
 * Tom St Denis, [email protected], http://libtomcrypt.com
 */

#define DESC_DEF_ONLY
#include "tomcrypt.h"

#ifdef TFM_DESC

#include <tfm.h>

static const struct {
    int tfm_code, ltc_code;
} tfm_to_ltc_codes[] = {
   { FP_OKAY ,  CRYPT_OK},
   { FP_MEM  ,  CRYPT_MEM},
   { FP_VAL  ,  CRYPT_INVALID_ARG},
};

/**
   Convert a tfm error to a LTC error (Possibly the most powerful function ever!  Oh wait... no) 
   @param err    The error to convert
   @return The equivalent LTC error code or CRYPT_ERROR if none found
*/
static int tfm_to_ltc_error(int err)
{
   int x;

   for (x = 0; x < (int)(sizeof(tfm_to_ltc_codes)/sizeof(tfm_to_ltc_codes[0])); x++) {
       if (err == tfm_to_ltc_codes[x].tfm_code) { 
          return tfm_to_ltc_codes[x].ltc_code;
       }
   }
   return CRYPT_ERROR;
}

static int init(void **a)
{
   LTC_ARGCHK(a != NULL);

   *a = XCALLOC(1, sizeof(fp_int));
   if (*a == NULL) {
      return CRYPT_MEM;
   }
   fp_init(*a);
   return CRYPT_OK;
}

static void deinit(void *a)
{
   LTC_ARGCHKVD(a != NULL);
   XFREE(a);
}

static int neg(void *a, void *b)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   fp_neg(((fp_int*)a), ((fp_int*)b));
   return CRYPT_OK;
}

static int copy(void *a, void *b)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   fp_copy(a, b);
   return CRYPT_OK;
}

static int init_copy(void **a, void *b)
{
   if (init(a) != CRYPT_OK) {
      return CRYPT_MEM;
   }
   return copy(b, *a);
}

/* ---- trivial ---- */
static int set_int(void *a, unsigned long b)
{
   LTC_ARGCHK(a != NULL);
   fp_set(a, b);
   return CRYPT_OK;
}

static unsigned long get_int(void *a)
{
   fp_int *A;
   LTC_ARGCHK(a != NULL);
   A = a;
   return A->used > 0 ? A->dp[0] : 0;
}

static unsigned long get_digit(void *a, int n)
{
   fp_int *A;
   LTC_ARGCHK(a != NULL);
   A = a;
   return (n >= A->used || n < 0) ? 0 : A->dp[n];
}

static int get_digit_count(void *a)
{
   fp_int *A;
   LTC_ARGCHK(a != NULL);
   A = a;
   return A->used;
}
   
static int compare(void *a, void *b)
{
   int ret;
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   ret = fp_cmp(a, b);
   switch (ret) {
      case FP_LT: return LTC_MP_LT;
      case FP_EQ: return LTC_MP_EQ;
      case FP_GT: return LTC_MP_GT;
   }
   return 0;
}

static int compare_d(void *a, unsigned long b)
{
   int ret;
   LTC_ARGCHK(a != NULL);
   ret = fp_cmp_d(a, b);
   switch (ret) {
      case FP_LT: return LTC_MP_LT;
      case FP_EQ: return LTC_MP_EQ;
      case FP_GT: return LTC_MP_GT;
   }
   return 0;
}

static int count_bits(void *a)
{
   LTC_ARGCHK(a != NULL);
   return fp_count_bits(a);
}

static int count_lsb_bits(void *a)
{
   LTC_ARGCHK(a != NULL);
   return fp_cnt_lsb(a);
}

static int twoexpt(void *a, int n)
{
   LTC_ARGCHK(a != NULL);
   fp_2expt(a, n);
   return CRYPT_OK;
}

/* ---- conversions ---- */

/* read ascii string */
static int read_radix(void *a, const char *b, int radix)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   return tfm_to_ltc_error(fp_read_radix(a, (char *)b, radix));
}

/* write one */
static int write_radix(void *a, char *b, int radix)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   return tfm_to_ltc_error(fp_toradix(a, b, radix));
}

/* get size as unsigned char string */
static unsigned long unsigned_size(void *a)
{
   LTC_ARGCHK(a != NULL);
   return fp_unsigned_bin_size(a);
}

/* store */
static int unsigned_write(void *a, unsigned char *b)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   fp_to_unsigned_bin(a, b);
   return CRYPT_OK;
}

/* read */
static int unsigned_read(void *a, unsigned char *b, unsigned long len)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   fp_read_unsigned_bin(a, b, len);
   return CRYPT_OK;
}

/* add */
static int add(void *a, void *b, void *c)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   LTC_ARGCHK(c != NULL);
   fp_add(a, b, c);
   return CRYPT_OK;
}
  
static int addi(void *a, unsigned long b, void *c)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(c != NULL);
   fp_add_d(a, b, c);
   return CRYPT_OK;
}

/* sub */
static int sub(void *a, void *b, void *c)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   LTC_ARGCHK(c != NULL);
   fp_sub(a, b, c);
   return CRYPT_OK;
}

static int subi(void *a, unsigned long b, void *c)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(c != NULL);
   fp_sub_d(a, b, c);
   return CRYPT_OK;
}

/* mul */
static int mul(void *a, void *b, void *c)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   LTC_ARGCHK(c != NULL);
   fp_mul(a, b, c); 
   return CRYPT_OK;
}

static int muli(void *a, unsigned long b, void *c)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(c != NULL);
   fp_mul_d(a, b, c);
   return CRYPT_OK;
}

/* sqr */
static int sqr(void *a, void *b)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   fp_sqr(a, b);
   return CRYPT_OK;
}

/* div */
static int divide(void *a, void *b, void *c, void *d)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   return tfm_to_ltc_error(fp_div(a, b, c, d));
}

static int div_2(void *a, void *b)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   fp_div_2(a, b);
   return CRYPT_OK;
}

/* modi */
static int modi(void *a, unsigned long b, unsigned long *c)
{
   fp_digit tmp;
   int      err;

   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(c != NULL);

   if ((err = tfm_to_ltc_error(fp_mod_d(a, b, &tmp))) != CRYPT_OK) {
      return err;
   }
   *c = tmp;
   return CRYPT_OK;
}  

/* gcd */
static int gcd(void *a, void *b, void *c)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   LTC_ARGCHK(c != NULL);
   fp_gcd(a, b, c);
   return CRYPT_OK;
}

/* lcm */
static int lcm(void *a, void *b, void *c)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   LTC_ARGCHK(c != NULL);
   fp_lcm(a, b, c);
   return CRYPT_OK;
}

static int mulmod(void *a, void *b, void *c, void *d)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   LTC_ARGCHK(c != NULL);
   LTC_ARGCHK(d != NULL);
   return tfm_to_ltc_error(fp_mulmod(a,b,c,d));
}

static int sqrmod(void *a, void *b, void *c)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   LTC_ARGCHK(c != NULL);
   return tfm_to_ltc_error(fp_sqrmod(a,b,c));
}

/* invmod */
static int invmod(void *a, void *b, void *c)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   LTC_ARGCHK(c != NULL);
   return tfm_to_ltc_error(fp_invmod(a, b, c));
}

/* setup */
static int montgomery_setup(void *a, void **b)
{
   int err;
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   *b = XCALLOC(1, sizeof(fp_digit));
   if (*b == NULL) {
      return CRYPT_MEM;
   }
   if ((err = tfm_to_ltc_error(fp_montgomery_setup(a, (fp_digit *)*b))) != CRYPT_OK) {
      XFREE(*b);
   }
   return err;
}

/* get normalization value */
static int montgomery_normalization(void *a, void *b)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   fp_montgomery_calc_normalization(a, b);
   return CRYPT_OK;
}

/* reduce */
static int montgomery_reduce(void *a, void *b, void *c)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   LTC_ARGCHK(c != NULL);
   fp_montgomery_reduce(a, b, *((fp_digit *)c));
   return CRYPT_OK;
}

/* clean up */
static void montgomery_deinit(void *a)
{
   XFREE(a);
}

static int exptmod(void *a, void *b, void *c, void *d)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   LTC_ARGCHK(c != NULL);
   LTC_ARGCHK(d != NULL);
   return tfm_to_ltc_error(fp_exptmod(a,b,c,d));
}   

static int isprime(void *a, int *b)
{
   LTC_ARGCHK(a != NULL);
   LTC_ARGCHK(b != NULL);
   *b = (fp_isprime(a) == FP_YES) ? LTC_MP_YES : LTC_MP_NO;
   return CRYPT_OK;
}

#if defined(MECC) && defined(MECC_ACCEL)

static int tfm_ecc_projective_dbl_point(ecc_point *P, ecc_point *R, void *modulus, void *Mp)
{
   fp_int t1, t2;
   fp_digit mp;

   LTC_ARGCHK(P       != NULL);
   LTC_ARGCHK(R       != NULL);
   LTC_ARGCHK(modulus != NULL);
   LTC_ARGCHK(Mp      != NULL);

   mp = *((fp_digit*)Mp);

   fp_init(&t1);
   fp_init(&t2);

   if (P != R) {
      fp_copy(P->x, R->x);
      fp_copy(P->y, R->y);
      fp_copy(P->z, R->z);
   }

   /* t1 = Z * Z */
   fp_sqr(R->z, &t1);
   fp_montgomery_reduce(&t1, modulus, mp);
   /* Z = Y * Z */
   fp_mul(R->z, R->y, R->z);
   fp_montgomery_reduce(R->z, modulus, mp);
   /* Z = 2Z */
   fp_add(R->z, R->z, R->z);
   if (fp_cmp(R->z, modulus) != FP_LT) {
      fp_sub(R->z, modulus, R->z);
   }
   
   /* &t2 = X - T1 */
   fp_sub(R->x, &t1, &t2);
   if (fp_cmp_d(&t2, 0) == FP_LT) {
      fp_add(&t2, modulus, &t2);
   }
   /* T1 = X + T1 */
   fp_add(&t1, R->x, &t1);
   if (fp_cmp(&t1, modulus) != FP_LT) {
      fp_sub(&t1, modulus, &t1);
   }
   /* T2 = T1 * T2 */
   fp_mul(&t1, &t2, &t2);
   fp_montgomery_reduce(&t2, modulus, mp);
   /* T1 = 2T2 */
   fp_add(&t2, &t2, &t1);
   if (fp_cmp(&t1, modulus) != FP_LT) {
      fp_sub(&t1, modulus, &t1);
   }
   /* T1 = T1 + T2 */
   fp_add(&t1, &t2, &t1);
   if (fp_cmp(&t1, modulus) != FP_LT) {
      fp_sub(&t1, modulus, &t1);
   }

   /* Y = 2Y */
   fp_add(R->y, R->y, R->y);
   if (fp_cmp(R->y, modulus) != FP_LT) {
      fp_sub(R->y, modulus, R->y);
   }
   /* Y = Y * Y */
   fp_sqr(R->y, R->y);
   fp_montgomery_reduce(R->y, modulus, mp);
   /* T2 = Y * Y */
   fp_sqr(R->y, &t2);
   fp_montgomery_reduce(&t2, modulus, mp);
   /* T2 = T2/2 */
   if (fp_isodd(&t2)) {
      fp_add(&t2, modulus, &t2);
   }
   fp_div_2(&t2, &t2);
   /* Y = Y * X */
   fp_mul(R->y, R->x, R->y);
   fp_montgomery_reduce(R->y, modulus, mp);

   /* X  = T1 * T1 */
   fp_sqr(&t1, R->x);
   fp_montgomery_reduce(R->x, modulus, mp);
   /* X = X - Y */
   fp_sub(R->x, R->y, R->x);
   if (fp_cmp_d(R->x, 0) == FP_LT) {
      fp_add(R->x, modulus, R->x);
   }
   /* X = X - Y */
   fp_sub(R->x, R->y, R->x);
   if (fp_cmp_d(R->x, 0) == FP_LT) {
      fp_add(R->x, modulus, R->x);
   }

   /* Y = Y - X */     
   fp_sub(R->y, R->x, R->y);
   if (fp_cmp_d(R->y, 0) == FP_LT) {
      fp_add(R->y, modulus, R->y);
   }
   /* Y = Y * T1 */
   fp_mul(R->y, &t1, R->y);
   fp_montgomery_reduce(R->y, modulus, mp);
   /* Y = Y - T2 */
   fp_sub(R->y, &t2, R->y);
   if (fp_cmp_d(R->y, 0) == FP_LT) {
      fp_add(R->y, modulus, R->y);
   }
 
   return CRYPT_OK;
}

/**
   Add two ECC points
   @param P        The point to add
   @param Q        The point to add
   @param R        [out] The destination of the double
   @param modulus  The modulus of the field the ECC curve is in
   @param mp       The "b" value from montgomery_setup()
   @return CRYPT_OK on success
*/
static int tfm_ecc_projective_add_point(ecc_point *P, ecc_point *Q, ecc_point *R, void *modulus, void *Mp)
{
   fp_int  t1, t2, x, y, z;
   fp_digit mp;  
   
   LTC_ARGCHK(P       != NULL);
   LTC_ARGCHK(Q       != NULL);
   LTC_ARGCHK(R       != NULL);
   LTC_ARGCHK(modulus != NULL);
   LTC_ARGCHK(Mp      != NULL);

   mp = *((fp_digit*)Mp);

   fp_init(&t1);
   fp_init(&t2);
   fp_init(&x);
   fp_init(&y);
   fp_init(&z);

   /* should we dbl instead? */
   fp_sub(modulus, Q->y, &t1);
   if ( (fp_cmp(P->x, Q->x) == FP_EQ) && 
        (Q->z != NULL && fp_cmp(P->z, Q->z) == FP_EQ) &&
        (fp_cmp(P->y, Q->y) == FP_EQ || fp_cmp(P->y, &t1) == FP_EQ)) {
        return tfm_ecc_projective_dbl_point(P, R, modulus, Mp);
   }

   fp_copy(P->x, &x);
   fp_copy(P->y, &y);
   fp_copy(P->z, &z);

   /* if Z is one then these are no-operations */
   if (Q->z != NULL) {
      /* T1 = Z' * Z' */
      fp_sqr(Q->z, &t1);
      fp_montgomery_reduce(&t1, modulus, mp);
      /* X = X * T1 */
      fp_mul(&t1, &x, &x);
      fp_montgomery_reduce(&x, modulus, mp);
      /* T1 = Z' * T1 */
      fp_mul(Q->z, &t1, &t1);
      fp_montgomery_reduce(&t1, modulus, mp);
      /* Y = Y * T1 */
      fp_mul(&t1, &y, &y);
      fp_montgomery_reduce(&y, modulus, mp);
   }

   /* T1 = Z*Z */
   fp_sqr(&z, &t1);
   fp_montgomery_reduce(&t1, modulus, mp);
   /* T2 = X' * T1 */
   fp_mul(Q->x, &t1, &t2);
   fp_montgomery_reduce(&t2, modulus, mp);
   /* T1 = Z * T1 */
   fp_mul(&z, &t1, &t1);
   fp_montgomery_reduce(&t1, modulus, mp);
   /* T1 = Y' * T1 */
   fp_mul(Q->y, &t1, &t1);
   fp_montgomery_reduce(&t1, modulus, mp);

   /* Y = Y - T1 */
   fp_sub(&y, &t1, &y);
   if (fp_cmp_d(&y, 0) == FP_LT) {
      fp_add(&y, modulus, &y);
   }
   /* T1 = 2T1 */
   fp_add(&t1, &t1, &t1);
   if (fp_cmp(&t1, modulus) != FP_LT) {
      fp_sub(&t1, modulus, &t1);
   }
   /* T1 = Y + T1 */
   fp_add(&t1, &y, &t1);
   if (fp_cmp(&t1, modulus) != FP_LT) {
      fp_sub(&t1, modulus, &t1);
   }
   /* X = X - T2 */
   fp_sub(&x, &t2, &x);
   if (fp_cmp_d(&x, 0) == FP_LT) {
      fp_add(&x, modulus, &x);
   }
   /* T2 = 2T2 */
   fp_add(&t2, &t2, &t2);
   if (fp_cmp(&t2, modulus) != FP_LT) {
      fp_sub(&t2, modulus, &t2);
   }
   /* T2 = X + T2 */
   fp_add(&t2, &x, &t2);
   if (fp_cmp(&t2, modulus) != FP_LT) {
      fp_sub(&t2, modulus, &t2);
   }

   /* if Z' != 1 */
   if (Q->z != NULL) {
      /* Z = Z * Z' */
      fp_mul(&z, Q->z, &z);
      fp_montgomery_reduce(&z, modulus, mp);
   }

   /* Z = Z * X */
   fp_mul(&z, &x, &z);
   fp_montgomery_reduce(&z, modulus, mp);

   /* T1 = T1 * X  */
   fp_mul(&t1, &x, &t1);
   fp_montgomery_reduce(&t1, modulus, mp);
   /* X = X * X */
   fp_sqr(&x, &x);
   fp_montgomery_reduce(&x, modulus, mp);
   /* T2 = T2 * x */
   fp_mul(&t2, &x, &t2);
   fp_montgomery_reduce(&t2, modulus, mp);
   /* T1 = T1 * X  */
   fp_mul(&t1, &x, &t1);
   fp_montgomery_reduce(&t1, modulus, mp);
 
   /* X = Y*Y */
   fp_sqr(&y, &x);
   fp_montgomery_reduce(&x, modulus, mp);
   /* X = X - T2 */
   fp_sub(&x, &t2, &x);
   if (fp_cmp_d(&x, 0) == FP_LT) {
      fp_add(&x, modulus, &x);
   }

   /* T2 = T2 - X */
   fp_sub(&t2, &x, &t2);
   if (fp_cmp_d(&t2, 0) == FP_LT) {
      fp_add(&t2, modulus, &t2);
   } 
   /* T2 = T2 - X */
   fp_sub(&t2, &x, &t2);
   if (fp_cmp_d(&t2, 0) == FP_LT) {
      fp_add(&t2, modulus, &t2);
   }
   /* T2 = T2 * Y */
   fp_mul(&t2, &y, &t2);
   fp_montgomery_reduce(&t2, modulus, mp);
   /* Y = T2 - T1 */
   fp_sub(&t2, &t1, &y);
   if (fp_cmp_d(&y, 0) == FP_LT) {
      fp_add(&y, modulus, &y);
   }
   /* Y = Y/2 */
   if (fp_isodd(&y)) {
      fp_add(&y, modulus, &y);
   }
   fp_div_2(&y, &y);

   fp_copy(&x, R->x);
   fp_copy(&y, R->y);
   fp_copy(&z, R->z);
   
   return CRYPT_OK;
}


#endif

const ltc_math_descriptor tfm_desc = {

   "TomsFastMath",
   (int)DIGIT_BIT,

   &init,
   &init_copy,
   &deinit,

   &neg,
   &copy,

   &set_int,
   &get_int,
   &get_digit,
   &get_digit_count,
   &compare,
   &compare_d,
   &count_bits,
   &count_lsb_bits,
   &twoexpt,

   &read_radix,
   &write_radix,
   &unsigned_size,
   &unsigned_write,
   &unsigned_read,

   &add,
   &addi,
   &sub,
   &subi,
   &mul,
   &muli,
   &sqr,
   &divide,
   &div_2,
   &modi,
   &gcd,
   &lcm,

   &mulmod,
   &sqrmod,
   &invmod,

   &montgomery_setup,
   &montgomery_normalization,
   &montgomery_reduce,
   &montgomery_deinit,

   &exptmod,
   &isprime,

#ifdef MECC
#ifdef MECC_FP
   &ltc_ecc_fp_mulmod,
#else
   &ltc_ecc_mulmod,
#endif /* MECC_FP */
#ifdef MECC_ACCEL
   &tfm_ecc_projective_add_point,
   &tfm_ecc_projective_dbl_point,
#else
   &ltc_ecc_projective_add_point,
   &ltc_ecc_projective_dbl_point,
#endif /* MECC_ACCEL */
   &ltc_ecc_map,
#ifdef LTC_ECC_SHAMIR
#ifdef MECC_FP
   &ltc_ecc_fp_mul2add,
#else
   &ltc_ecc_mul2add,
#endif /* MECC_FP */
#else
   NULL,
#endif /* LTC_ECC_SHAMIR */
#else
   NULL, NULL, NULL, NULL, NULL,
#endif /* MECC */

#ifdef MRSA
   &rsa_make_key,
   &rsa_exptmod,
#else
   NULL, NULL
#endif
   
};


#endif

/* $Source: /cvs/libtom/libtomcrypt/src/math/tfm_desc.c,v $ */
/* $Revision: 1.26 $ */
/* $Date: 2006/12/03 00:39:56 $ */