1 /* LibTomMath, multiple-precision integer library -- Tom St Denis
3 * LibTomMath is a library that provides multiple-precision
4 * integer arithmetic as well as number theoretic functionality.
6 * The library was designed directly after the MPI library by
7 * Michael Fromberger but has been written from scratch with
8 * additional optimizations in place.
10 * The library is free for all purposes without any express
13 * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com
24 #include "tommath_class.h"
27 #define MIN(x,y) ((x)<(y)?(x):(y))
31 #define MAX(x,y) ((x)>(y)?(x):(y))
37 /* C++ compilers don't like assigning void * to mp_digit * */
38 #define OPT_CAST(x) (x *)
42 /* C on the other hand doesn't care */
48 /* detect 64-bit mode if possible */
49 #if defined(__x86_64__)
50 #if !(defined(MP_64BIT) && defined(MP_16BIT) && defined(MP_8BIT))
55 /* some default configurations.
57 * A "mp_digit" must be able to hold DIGIT_BIT + 1 bits
58 * A "mp_word" must be able to hold 2*DIGIT_BIT + 1 bits
60 * At the very least a mp_digit must be able to hold 7 bits
61 * [any size beyond that is ok provided it doesn't overflow the data type]
64 typedef unsigned char mp_digit
;
65 typedef unsigned short mp_word
;
66 #elif defined(MP_16BIT)
67 typedef unsigned short mp_digit
;
68 typedef unsigned long mp_word
;
69 #elif defined(MP_64BIT)
70 /* for GCC only on supported platforms */
72 typedef unsigned long long ulong64
;
73 typedef signed long long long64
;
76 typedef unsigned long mp_digit
;
77 typedef unsigned long mp_word
__attribute__ ((mode(TI
)));
81 /* this is the default case, 28-bit digits */
83 /* this is to make porting into LibTomCrypt easier :-) */
85 #if defined(_MSC_VER) || defined(__BORLANDC__)
86 typedef unsigned __int64 ulong64
;
87 typedef signed __int64 long64
;
89 typedef unsigned long long ulong64
;
90 typedef signed long long long64
;
94 typedef unsigned long mp_digit
;
95 typedef ulong64 mp_word
;
98 /* this is an extension that uses 31-bit digits */
101 /* default case is 28-bit digits, defines MP_28BIT as a handy macro to test */
107 /* define heap macros */
109 /* default to libc stuff */
111 #define XMALLOC malloc
113 #define XREALLOC realloc
114 #define XCALLOC calloc
116 /* prototypes for our heap functions */
117 extern void *XMALLOC(size_t n
);
118 extern void *XREALLOC(void *p
, size_t n
);
119 extern void *XCALLOC(size_t n
, size_t s
);
120 extern void XFREE(void *p
);
125 /* otherwise the bits per digit is calculated automatically from the size of a mp_digit */
127 #define DIGIT_BIT ((int)((CHAR_BIT * sizeof(mp_digit) - 1))) /* bits per digit */
130 #define MP_DIGIT_BIT DIGIT_BIT
131 #define MP_MASK ((((mp_digit)1)<<((mp_digit)DIGIT_BIT))-((mp_digit)1))
132 #define MP_DIGIT_MAX MP_MASK
135 #define MP_LT -1 /* less than */
136 #define MP_EQ 0 /* equal to */
137 #define MP_GT 1 /* greater than */
139 #define MP_ZPOS 0 /* positive integer */
140 #define MP_NEG 1 /* negative */
142 #define MP_OKAY 0 /* ok result */
143 #define MP_MEM -2 /* out of mem */
144 #define MP_VAL -3 /* invalid input */
145 #define MP_RANGE MP_VAL
147 #define MP_YES 1 /* yes response */
148 #define MP_NO 0 /* no response */
150 /* Primality generation flags */
151 #define LTM_PRIME_BBS 0x0001 /* BBS style prime */
152 #define LTM_PRIME_SAFE 0x0002 /* Safe prime (p-1)/2 == prime */
153 #define LTM_PRIME_2MSB_ON 0x0008 /* force 2nd MSB to 1 */
157 /* you'll have to tune these... */
158 extern int KARATSUBA_MUL_CUTOFF
,
159 KARATSUBA_SQR_CUTOFF
,
163 /* define this to use lower memory usage routines (exptmods mostly) */
164 /* #define MP_LOW_MEM */
166 /* default precision */
169 #define MP_PREC 32 /* default digits of precision */
171 #define MP_PREC 8 /* default digits of precision */
175 /* size of comba arrays, should be at least 2 * 2**(BITS_PER_WORD - BITS_PER_DIGIT*2) */
176 #define MP_WARRAY (1 << (sizeof(mp_word) * CHAR_BIT - 2 * DIGIT_BIT + 1))
178 /* the infamous mp_int structure */
180 int used
, alloc
, sign
;
184 /* callback for mp_prime_random, should fill dst with random bytes and return how many read [upto len] */
185 typedef int ltm_prime_callback(unsigned char *dst
, int len
, void *dat
);
188 #define USED(m) ((m)->used)
189 #define DIGIT(m,k) ((m)->dp[(k)])
190 #define SIGN(m) ((m)->sign)
192 /* error code to char* string */
193 char *mp_error_to_string(int code
);
195 /* ---> init and deinit bignum functions <--- */
197 int mp_init(mp_int
*a
);
200 void mp_clear(mp_int
*a
);
202 /* init a null terminated series of arguments */
203 int mp_init_multi(mp_int
*mp
, ...);
205 /* clear a null terminated series of arguments */
206 void mp_clear_multi(mp_int
*mp
, ...);
208 /* exchange two ints */
209 void mp_exch(mp_int
*a
, mp_int
*b
);
211 /* shrink ram required for a bignum */
212 int mp_shrink(mp_int
*a
);
214 /* grow an int to a given size */
215 int mp_grow(mp_int
*a
, int size
);
217 /* init to a given number of digits */
218 int mp_init_size(mp_int
*a
, int size
);
220 /* ---> Basic Manipulations <--- */
221 #define mp_iszero(a) (((a)->used == 0) ? MP_YES : MP_NO)
222 #define mp_iseven(a) (((a)->used > 0 && (((a)->dp[0] & 1) == 0)) ? MP_YES : MP_NO)
223 #define mp_isodd(a) (((a)->used > 0 && (((a)->dp[0] & 1) == 1)) ? MP_YES : MP_NO)
226 void mp_zero(mp_int
*a
);
229 void mp_set(mp_int
*a
, mp_digit b
);
231 /* set a 32-bit const */
232 int mp_set_int(mp_int
*a
, unsigned long b
);
234 /* get a 32-bit value */
235 unsigned long mp_get_int(mp_int
* a
);
237 /* initialize and set a digit */
238 int mp_init_set (mp_int
* a
, mp_digit b
);
240 /* initialize and set 32-bit value */
241 int mp_init_set_int (mp_int
* a
, unsigned long b
);
244 int mp_copy(mp_int
*a
, mp_int
*b
);
246 /* inits and copies, a = b */
247 int mp_init_copy(mp_int
*a
, mp_int
*b
);
249 /* trim unused digits */
250 void mp_clamp(mp_int
*a
);
252 /* ---> digit manipulation <--- */
254 /* right shift by "b" digits */
255 void mp_rshd(mp_int
*a
, int b
);
257 /* left shift by "b" digits */
258 int mp_lshd(mp_int
*a
, int b
);
261 int mp_div_2d(mp_int
*a
, int b
, mp_int
*c
, mp_int
*d
);
264 int mp_div_2(mp_int
*a
, mp_int
*b
);
267 int mp_mul_2d(mp_int
*a
, int b
, mp_int
*c
);
270 int mp_mul_2(mp_int
*a
, mp_int
*b
);
273 int mp_mod_2d(mp_int
*a
, int b
, mp_int
*c
);
275 /* computes a = 2**b */
276 int mp_2expt(mp_int
*a
, int b
);
278 /* Counts the number of lsbs which are zero before the first zero bit */
279 int mp_cnt_lsb(mp_int
*a
);
283 /* makes a pseudo-random int of a given size */
284 int mp_rand(mp_int
*a
, int digits
);
286 /* ---> binary operations <--- */
288 int mp_xor(mp_int
*a
, mp_int
*b
, mp_int
*c
);
291 int mp_or(mp_int
*a
, mp_int
*b
, mp_int
*c
);
294 int mp_and(mp_int
*a
, mp_int
*b
, mp_int
*c
);
296 /* ---> Basic arithmetic <--- */
299 int mp_neg(mp_int
*a
, mp_int
*b
);
302 int mp_abs(mp_int
*a
, mp_int
*b
);
305 int mp_cmp(mp_int
*a
, mp_int
*b
);
307 /* compare |a| to |b| */
308 int mp_cmp_mag(mp_int
*a
, mp_int
*b
);
311 int mp_add(mp_int
*a
, mp_int
*b
, mp_int
*c
);
314 int mp_sub(mp_int
*a
, mp_int
*b
, mp_int
*c
);
317 int mp_mul(mp_int
*a
, mp_int
*b
, mp_int
*c
);
320 int mp_sqr(mp_int
*a
, mp_int
*b
);
322 /* a/b => cb + d == a */
323 int mp_div(mp_int
*a
, mp_int
*b
, mp_int
*c
, mp_int
*d
);
325 /* c = a mod b, 0 <= c < b */
326 int mp_mod(mp_int
*a
, mp_int
*b
, mp_int
*c
);
328 /* ---> single digit functions <--- */
330 /* compare against a single digit */
331 int mp_cmp_d(mp_int
*a
, mp_digit b
);
334 int mp_add_d(mp_int
*a
, mp_digit b
, mp_int
*c
);
337 int mp_sub_d(mp_int
*a
, mp_digit b
, mp_int
*c
);
340 int mp_mul_d(mp_int
*a
, mp_digit b
, mp_int
*c
);
342 /* a/b => cb + d == a */
343 int mp_div_d(mp_int
*a
, mp_digit b
, mp_int
*c
, mp_digit
*d
);
345 /* a/3 => 3c + d == a */
346 int mp_div_3(mp_int
*a
, mp_int
*c
, mp_digit
*d
);
349 int mp_expt_d(mp_int
*a
, mp_digit b
, mp_int
*c
);
351 /* c = a mod b, 0 <= c < b */
352 int mp_mod_d(mp_int
*a
, mp_digit b
, mp_digit
*c
);
354 /* ---> number theory <--- */
356 /* d = a + b (mod c) */
357 int mp_addmod(mp_int
*a
, mp_int
*b
, mp_int
*c
, mp_int
*d
);
359 /* d = a - b (mod c) */
360 int mp_submod(mp_int
*a
, mp_int
*b
, mp_int
*c
, mp_int
*d
);
362 /* d = a * b (mod c) */
363 int mp_mulmod(mp_int
*a
, mp_int
*b
, mp_int
*c
, mp_int
*d
);
365 /* c = a * a (mod b) */
366 int mp_sqrmod(mp_int
*a
, mp_int
*b
, mp_int
*c
);
368 /* c = 1/a (mod b) */
369 int mp_invmod(mp_int
*a
, mp_int
*b
, mp_int
*c
);
372 int mp_gcd(mp_int
*a
, mp_int
*b
, mp_int
*c
);
374 /* produces value such that U1*a + U2*b = U3 */
375 int mp_exteuclid(mp_int
*a
, mp_int
*b
, mp_int
*U1
, mp_int
*U2
, mp_int
*U3
);
377 /* c = [a, b] or (a*b)/(a, b) */
378 int mp_lcm(mp_int
*a
, mp_int
*b
, mp_int
*c
);
380 /* finds one of the b'th root of a, such that |c|**b <= |a|
382 * returns error if a < 0 and b is even
384 int mp_n_root(mp_int
*a
, mp_digit b
, mp_int
*c
);
386 /* special sqrt algo */
387 int mp_sqrt(mp_int
*arg
, mp_int
*ret
);
389 /* is number a square? */
390 int mp_is_square(mp_int
*arg
, int *ret
);
392 /* computes the jacobi c = (a | n) (or Legendre if b is prime) */
393 int mp_jacobi(mp_int
*a
, mp_int
*n
, int *c
);
395 /* used to setup the Barrett reduction for a given modulus b */
396 int mp_reduce_setup(mp_int
*a
, mp_int
*b
);
398 /* Barrett Reduction, computes a (mod b) with a precomputed value c
400 * Assumes that 0 < a <= b*b, note if 0 > a > -(b*b) then you can merely
401 * compute the reduction as -1 * mp_reduce(mp_abs(a)) [pseudo code].
403 int mp_reduce(mp_int
*a
, mp_int
*b
, mp_int
*c
);
405 /* setups the montgomery reduction */
406 int mp_montgomery_setup(mp_int
*a
, mp_digit
*mp
);
408 /* computes a = B**n mod b without division or multiplication useful for
409 * normalizing numbers in a Montgomery system.
411 int mp_montgomery_calc_normalization(mp_int
*a
, mp_int
*b
);
413 /* computes x/R == x (mod N) via Montgomery Reduction */
414 int mp_montgomery_reduce(mp_int
*a
, mp_int
*m
, mp_digit mp
);
416 /* returns 1 if a is a valid DR modulus */
417 int mp_dr_is_modulus(mp_int
*a
);
419 /* sets the value of "d" required for mp_dr_reduce */
420 void mp_dr_setup(mp_int
*a
, mp_digit
*d
);
422 /* reduces a modulo b using the Diminished Radix method */
423 int mp_dr_reduce(mp_int
*a
, mp_int
*b
, mp_digit mp
);
425 /* returns true if a can be reduced with mp_reduce_2k */
426 int mp_reduce_is_2k(mp_int
*a
);
428 /* determines k value for 2k reduction */
429 int mp_reduce_2k_setup(mp_int
*a
, mp_digit
*d
);
431 /* reduces a modulo b where b is of the form 2**p - k [0 <= a] */
432 int mp_reduce_2k(mp_int
*a
, mp_int
*n
, mp_digit d
);
434 /* returns true if a can be reduced with mp_reduce_2k_l */
435 int mp_reduce_is_2k_l(mp_int
*a
);
437 /* determines k value for 2k reduction */
438 int mp_reduce_2k_setup_l(mp_int
*a
, mp_int
*d
);
440 /* reduces a modulo b where b is of the form 2**p - k [0 <= a] */
441 int mp_reduce_2k_l(mp_int
*a
, mp_int
*n
, mp_int
*d
);
443 /* d = a**b (mod c) */
444 int mp_exptmod(mp_int
*a
, mp_int
*b
, mp_int
*c
, mp_int
*d
);
446 /* ---> Primes <--- */
448 /* number of primes */
450 #define PRIME_SIZE 31
452 #define PRIME_SIZE 256
455 /* table of first PRIME_SIZE primes */
456 extern const mp_digit ltm_prime_tab
[];
458 /* result=1 if a is divisible by one of the first PRIME_SIZE primes */
459 int mp_prime_is_divisible(mp_int
*a
, int *result
);
461 /* performs one Fermat test of "a" using base "b".
462 * Sets result to 0 if composite or 1 if probable prime
464 int mp_prime_fermat(mp_int
*a
, mp_int
*b
, int *result
);
466 /* performs one Miller-Rabin test of "a" using base "b".
467 * Sets result to 0 if composite or 1 if probable prime
469 int mp_prime_miller_rabin(mp_int
*a
, mp_int
*b
, int *result
);
471 /* This gives [for a given bit size] the number of trials required
472 * such that Miller-Rabin gives a prob of failure lower than 2^-96
474 int mp_prime_rabin_miller_trials(int size
);
476 /* performs t rounds of Miller-Rabin on "a" using the first
477 * t prime bases. Also performs an initial sieve of trial
478 * division. Determines if "a" is prime with probability
479 * of error no more than (1/4)**t.
481 * Sets result to 1 if probably prime, 0 otherwise
483 int mp_prime_is_prime(mp_int
*a
, int t
, int *result
);
485 /* finds the next prime after the number "a" using "t" trials
488 * bbs_style = 1 means the prime must be congruent to 3 mod 4
490 int mp_prime_next_prime(mp_int
*a
, int t
, int bbs_style
);
492 /* makes a truly random prime of a given size (bytes),
493 * call with bbs = 1 if you want it to be congruent to 3 mod 4
495 * You have to supply a callback which fills in a buffer with random bytes. "dat" is a parameter you can
496 * have passed to the callback (e.g. a state or something). This function doesn't use "dat" itself
499 * The prime generated will be larger than 2^(8*size).
501 #define mp_prime_random(a, t, size, bbs, cb, dat) mp_prime_random_ex(a, t, ((size) * 8) + 1, (bbs==1)?LTM_PRIME_BBS:0, cb, dat)
503 /* makes a truly random prime of a given size (bits),
505 * Flags are as follows:
507 * LTM_PRIME_BBS - make prime congruent to 3 mod 4
508 * LTM_PRIME_SAFE - make sure (p-1)/2 is prime as well (implies LTM_PRIME_BBS)
509 * LTM_PRIME_2MSB_OFF - make the 2nd highest bit zero
510 * LTM_PRIME_2MSB_ON - make the 2nd highest bit one
512 * You have to supply a callback which fills in a buffer with random bytes. "dat" is a parameter you can
513 * have passed to the callback (e.g. a state or something). This function doesn't use "dat" itself
517 int mp_prime_random_ex(mp_int
*a
, int t
, int size
, int flags
, ltm_prime_callback cb
, void *dat
);
519 /* ---> radix conversion <--- */
520 int mp_count_bits(mp_int
*a
);
522 int mp_unsigned_bin_size(mp_int
*a
);
523 int mp_read_unsigned_bin(mp_int
*a
, const unsigned char *b
, int c
);
524 int mp_to_unsigned_bin(mp_int
*a
, unsigned char *b
);
525 int mp_to_unsigned_bin_n (mp_int
* a
, unsigned char *b
, unsigned long *outlen
);
527 int mp_signed_bin_size(mp_int
*a
);
528 int mp_read_signed_bin(mp_int
*a
, const unsigned char *b
, int c
);
529 int mp_to_signed_bin(mp_int
*a
, unsigned char *b
);
530 int mp_to_signed_bin_n (mp_int
* a
, unsigned char *b
, unsigned long *outlen
);
532 int mp_read_radix(mp_int
*a
, const char *str
, int radix
);
533 int mp_toradix(mp_int
*a
, char *str
, int radix
);
534 int mp_toradix_n(mp_int
* a
, char *str
, int radix
, int maxlen
);
535 int mp_radix_size(mp_int
*a
, int radix
, int *size
);
537 int mp_fread(mp_int
*a
, int radix
, FILE *stream
);
538 int mp_fwrite(mp_int
*a
, int radix
, FILE *stream
);
540 #define mp_read_raw(mp, str, len) mp_read_signed_bin((mp), (str), (len))
541 #define mp_raw_size(mp) mp_signed_bin_size(mp)
542 #define mp_toraw(mp, str) mp_to_signed_bin((mp), (str))
543 #define mp_read_mag(mp, str, len) mp_read_unsigned_bin((mp), (str), (len))
544 #define mp_mag_size(mp) mp_unsigned_bin_size(mp)
545 #define mp_tomag(mp, str) mp_to_unsigned_bin((mp), (str))
547 #define mp_tobinary(M, S) mp_toradix((M), (S), 2)
548 #define mp_tooctal(M, S) mp_toradix((M), (S), 8)
549 #define mp_todecimal(M, S) mp_toradix((M), (S), 10)
550 #define mp_tohex(M, S) mp_toradix((M), (S), 16)
552 /* lowlevel functions, do not call! */
553 int s_mp_add(mp_int
*a
, mp_int
*b
, mp_int
*c
);
554 int s_mp_sub(mp_int
*a
, mp_int
*b
, mp_int
*c
);
555 #define s_mp_mul(a, b, c) s_mp_mul_digs(a, b, c, (a)->used + (b)->used + 1)
556 int fast_s_mp_mul_digs(mp_int
*a
, mp_int
*b
, mp_int
*c
, int digs
);
557 int s_mp_mul_digs(mp_int
*a
, mp_int
*b
, mp_int
*c
, int digs
);
558 int fast_s_mp_mul_high_digs(mp_int
*a
, mp_int
*b
, mp_int
*c
, int digs
);
559 int s_mp_mul_high_digs(mp_int
*a
, mp_int
*b
, mp_int
*c
, int digs
);
560 int fast_s_mp_sqr(mp_int
*a
, mp_int
*b
);
561 int s_mp_sqr(mp_int
*a
, mp_int
*b
);
562 int mp_karatsuba_mul(mp_int
*a
, mp_int
*b
, mp_int
*c
);
563 int mp_toom_mul(mp_int
*a
, mp_int
*b
, mp_int
*c
);
564 int mp_karatsuba_sqr(mp_int
*a
, mp_int
*b
);
565 int mp_toom_sqr(mp_int
*a
, mp_int
*b
);
566 int fast_mp_invmod(mp_int
*a
, mp_int
*b
, mp_int
*c
);
567 int mp_invmod_slow (mp_int
* a
, mp_int
* b
, mp_int
* c
);
568 int fast_mp_montgomery_reduce(mp_int
*a
, mp_int
*m
, mp_digit mp
);
569 int mp_exptmod_fast(mp_int
*G
, mp_int
*X
, mp_int
*P
, mp_int
*Y
, int mode
);
570 int s_mp_exptmod (mp_int
* G
, mp_int
* X
, mp_int
* P
, mp_int
* Y
, int mode
);
571 void bn_reverse(unsigned char *s
, int len
);
573 extern const char *mp_s_rmap
;
582 /* $Source: /cvs/libtom/libtommath/tommath.h,v $ */
583 /* $Revision: 1.8 $ */
584 /* $Date: 2006/03/31 14:18:44 $ */