Commit 3cdcec43e64a0b1e9438805551d1823a968981d2
2019-10-29T18:41:25
first batch of simplifications
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diff --git a/mp_abs.c b/mp_abs.c
index 4ad1a4a..902279e 100644
--- a/mp_abs.c
+++ b/mp_abs.c
@@ -9,10 +9,9 @@
*/
mp_err mp_abs(const mp_int *a, mp_int *b)
{
- mp_err err;
-
/* copy a to b */
if (a != b) {
+ mp_err err;
if ((err = mp_copy(a, b)) != MP_OKAY) {
return err;
}
diff --git a/mp_add.c b/mp_add.c
index c78614b..bf7a61e 100644
--- a/mp_add.c
+++ b/mp_add.c
@@ -6,33 +6,24 @@
/* high level addition (handles signs) */
mp_err mp_add(const mp_int *a, const mp_int *b, mp_int *c)
{
- mp_sign sa, sb;
- mp_err err;
-
- /* get sign of both inputs */
- sa = a->sign;
- sb = b->sign;
-
/* handle two cases, not four */
- if (sa == sb) {
+ if (a->sign == b->sign) {
/* both positive or both negative */
/* add their magnitudes, copy the sign */
- c->sign = sa;
- err = s_mp_add(a, b, c);
- } else {
- /* one positive, the other negative */
- /* subtract the one with the greater magnitude from */
- /* the one of the lesser magnitude. The result gets */
- /* the sign of the one with the greater magnitude. */
- if (mp_cmp_mag(a, b) == MP_LT) {
- c->sign = sb;
- err = s_mp_sub(b, a, c);
- } else {
- c->sign = sa;
- err = s_mp_sub(a, b, c);
- }
+ c->sign = a->sign;
+ return s_mp_add(a, b, c);
}
- return err;
+
+ /* one positive, the other negative */
+ /* subtract the one with the greater magnitude from */
+ /* the one of the lesser magnitude. The result gets */
+ /* the sign of the one with the greater magnitude. */
+ if (mp_cmp_mag(a, b) == MP_LT) {
+ MP_EXCH(const mp_int *, a, b);
+ }
+
+ c->sign = a->sign;
+ return s_mp_sub(a, b, c);
}
#endif
diff --git a/mp_clear_multi.c b/mp_clear_multi.c
index 74406c7..9c7aed8 100644
--- a/mp_clear_multi.c
+++ b/mp_clear_multi.c
@@ -7,12 +7,11 @@
void mp_clear_multi(mp_int *mp, ...)
{
- mp_int *next_mp = mp;
va_list args;
va_start(args, mp);
- while (next_mp != NULL) {
- mp_clear(next_mp);
- next_mp = va_arg(args, mp_int *);
+ while (mp != NULL) {
+ mp_clear(mp);
+ mp = va_arg(args, mp_int *);
}
va_end(args);
}
diff --git a/mp_cmp.c b/mp_cmp.c
index a9bd910..b9c4592 100644
--- a/mp_cmp.c
+++ b/mp_cmp.c
@@ -8,19 +8,14 @@ mp_ord mp_cmp(const mp_int *a, const mp_int *b)
{
/* compare based on sign */
if (a->sign != b->sign) {
- if (a->sign == MP_NEG) {
- return MP_LT;
- } else {
- return MP_GT;
- }
+ return a->sign == MP_NEG ? MP_LT : MP_GT;
}
- /* compare digits */
+ /* if negative compare opposite direction */
if (a->sign == MP_NEG) {
- /* if negative compare opposite direction */
- return mp_cmp_mag(b, a);
- } else {
- return mp_cmp_mag(a, b);
+ MP_EXCH(const mp_int *, a, b);
}
+
+ return mp_cmp_mag(a, b);
}
#endif
diff --git a/mp_cmp_d.c b/mp_cmp_d.c
index 03d8e2c..0d98e05 100644
--- a/mp_cmp_d.c
+++ b/mp_cmp_d.c
@@ -17,12 +17,10 @@ mp_ord mp_cmp_d(const mp_int *a, mp_digit b)
}
/* compare the only digit of a to b */
- if (a->dp[0] > b) {
- return MP_GT;
- } else if (a->dp[0] < b) {
- return MP_LT;
- } else {
- return MP_EQ;
+ if (a->dp[0] != b) {
+ return a->dp[0] > b ? MP_GT : MP_LT;
}
+
+ return MP_EQ;
}
#endif
diff --git a/mp_cmp_mag.c b/mp_cmp_mag.c
index b3a7b04..e5e502b 100644
--- a/mp_cmp_mag.c
+++ b/mp_cmp_mag.c
@@ -6,34 +6,20 @@
/* compare maginitude of two ints (unsigned) */
mp_ord mp_cmp_mag(const mp_int *a, const mp_int *b)
{
- int n;
- const mp_digit *tmpa, *tmpb;
+ int n;
/* compare based on # of non-zero digits */
- if (a->used > b->used) {
- return MP_GT;
+ if (a->used != b->used) {
+ return a->used > b->used ? MP_GT : MP_LT;
}
- if (a->used < b->used) {
- return MP_LT;
- }
-
- /* alias for a */
- tmpa = a->dp + (a->used - 1);
-
- /* alias for b */
- tmpb = b->dp + (a->used - 1);
-
/* compare based on digits */
- for (n = 0; n < a->used; ++n, --tmpa, --tmpb) {
- if (*tmpa > *tmpb) {
- return MP_GT;
- }
-
- if (*tmpa < *tmpb) {
- return MP_LT;
+ for (n = a->used; n --> 0;) {
+ if (a->dp[n] != b->dp[n]) {
+ return a->dp[n] > b->dp[n] ? MP_GT : MP_LT;
}
}
+
return MP_EQ;
}
#endif
diff --git a/mp_cnt_lsb.c b/mp_cnt_lsb.c
index 7ae8bc1..8519ad1 100644
--- a/mp_cnt_lsb.c
+++ b/mp_cnt_lsb.c
@@ -3,7 +3,7 @@
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
-static const int lnz[16] = {
+static const char lnz[16] = {
4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0
};
@@ -11,7 +11,7 @@ static const int lnz[16] = {
int mp_cnt_lsb(const mp_int *a)
{
int x;
- mp_digit q, qq;
+ mp_digit q;
/* easy out */
if (mp_iszero(a)) {
@@ -25,11 +25,12 @@ int mp_cnt_lsb(const mp_int *a)
/* now scan this digit until a 1 is found */
if ((q & 1u) == 0u) {
+ mp_digit p;
do {
- qq = q & 15u;
- x += lnz[qq];
+ p = q & 15u;
+ x += lnz[p];
q >>= 4;
- } while (qq == 0u);
+ } while (p == 0u);
}
return x;
}
diff --git a/mp_copy.c b/mp_copy.c
index a7ac34a..cf4d5e0 100644
--- a/mp_copy.c
+++ b/mp_copy.c
@@ -7,8 +7,6 @@
mp_err mp_copy(const mp_int *a, mp_int *b)
{
int n;
- mp_digit *tmpa, *tmpb;
- mp_err err;
/* if dst == src do nothing */
if (a == b) {
@@ -17,27 +15,21 @@ mp_err mp_copy(const mp_int *a, mp_int *b)
/* grow dest */
if (b->alloc < a->used) {
+ mp_err err;
if ((err = mp_grow(b, a->used)) != MP_OKAY) {
return err;
}
}
/* zero b and copy the parameters over */
- /* pointer aliases */
-
- /* source */
- tmpa = a->dp;
-
- /* destination */
- tmpb = b->dp;
/* copy all the digits */
for (n = 0; n < a->used; n++) {
- *tmpb++ = *tmpa++;
+ b->dp[n] = a->dp[n];
}
/* clear high digits */
- MP_ZERO_DIGITS(tmpb, b->used - n);
+ MP_ZERO_DIGITS(b->dp + a->used, b->used - a->used);
/* copy used count and sign */
b->used = a->used;
diff --git a/mp_div.c b/mp_div.c
index 23a2acf..05b96dd 100644
--- a/mp_div.c
+++ b/mp_div.c
@@ -15,14 +15,14 @@ mp_err mp_div(const mp_int *a, const mp_int *b, mp_int *c, mp_int *d)
/* if a < b then q = 0, r = a */
if (mp_cmp_mag(a, b) == MP_LT) {
if (d != NULL) {
- err = mp_copy(a, d);
- } else {
- err = MP_OKAY;
+ if ((err = mp_copy(a, d)) != MP_OKAY) {
+ return err;
+ }
}
if (c != NULL) {
mp_zero(c);
}
- return err;
+ return MP_OKAY;
}
if (MP_HAS(S_MP_DIV_RECURSIVE)
@@ -31,11 +31,12 @@ mp_err mp_div(const mp_int *a, const mp_int *b, mp_int *c, mp_int *d)
err = s_mp_div_recursive(a, b, c, d);
} else if (MP_HAS(S_MP_DIV_SCHOOL)) {
err = s_mp_div_school(a, b, c, d);
- } else {
+ } else if (MP_HAS(S_MP_DIV_SMALL)) {
err = s_mp_div_small(a, b, c, d);
+ } else {
+ err = MP_VAL;
}
return err;
}
#endif
-
diff --git a/mp_div_3.c b/mp_div_3.c
index 5789b2d..c26692c 100644
--- a/mp_div_3.c
+++ b/mp_div_3.c
@@ -7,7 +7,7 @@
mp_err mp_div_3(const mp_int *a, mp_int *c, mp_digit *d)
{
mp_int q;
- mp_word w, t;
+ mp_word w;
mp_digit b;
mp_err err;
int ix;
@@ -22,7 +22,8 @@ mp_err mp_div_3(const mp_int *a, mp_int *c, mp_digit *d)
q.used = a->used;
q.sign = a->sign;
w = 0;
- for (ix = a->used - 1; ix >= 0; ix--) {
+ for (ix = a->used; ix --> 0;) {
+ mp_word t;
w = (w << (mp_word)MP_DIGIT_BIT) | (mp_word)a->dp[ix];
if (w >= 3u) {
@@ -57,7 +58,7 @@ mp_err mp_div_3(const mp_int *a, mp_int *c, mp_digit *d)
}
mp_clear(&q);
- return err;
+ return MP_OKAY;
}
#endif
diff --git a/mp_exch.c b/mp_exch.c
index 7bc4ee7..50b97d9 100644
--- a/mp_exch.c
+++ b/mp_exch.c
@@ -8,10 +8,6 @@
*/
void mp_exch(mp_int *a, mp_int *b)
{
- mp_int t;
-
- t = *a;
- *a = *b;
- *b = t;
+ MP_EXCH(mp_int, *a, *b);
}
#endif
diff --git a/mp_exptmod.c b/mp_exptmod.c
index e643ded..b917c0b 100644
--- a/mp_exptmod.c
+++ b/mp_exptmod.c
@@ -64,13 +64,15 @@ LBL_ERR:
/* if the modulus is odd or dr != 0 use the montgomery method */
if (MP_HAS(S_MP_EXPTMOD_FAST) && (mp_isodd(P) || (dr != 0))) {
return s_mp_exptmod_fast(G, X, P, Y, dr);
- } else if (MP_HAS(S_MP_EXPTMOD)) {
- /* otherwise use the generic Barrett reduction technique */
+ }
+
+ /* otherwise use the generic Barrett reduction technique */
+ if (MP_HAS(S_MP_EXPTMOD)) {
return s_mp_exptmod(G, X, P, Y, 0);
- } else {
- /* no exptmod for evens */
- return MP_VAL;
}
+
+ /* no exptmod for evens */
+ return MP_VAL;
}
#endif
diff --git a/mp_exteuclid.c b/mp_exteuclid.c
index eb8ad37..0d0bfd3 100644
--- a/mp_exteuclid.c
+++ b/mp_exteuclid.c
@@ -65,7 +65,6 @@ mp_err mp_exteuclid(const mp_int *a, const mp_int *b, mp_int *U1, mp_int *U2, mp
mp_exch(U3, &u3);
}
- err = MP_OKAY;
LBL_ERR:
mp_clear_multi(&u1, &u2, &u3, &v1, &v2, &v3, &t1, &t2, &t3, &q, &tmp, NULL);
return err;
diff --git a/mp_fread.c b/mp_fread.c
index 767e5a3..005c62a 100644
--- a/mp_fread.c
+++ b/mp_fread.c
@@ -32,7 +32,7 @@ mp_err mp_fread(mp_int *a, int radix, FILE *stream)
mp_zero(a);
do {
- int y;
+ uint8_t y;
unsigned pos;
ch = (radix <= 36) ? MP_TOUPPER(ch) : ch;
pos = (unsigned)(ch - (int)'(');
@@ -40,7 +40,7 @@ mp_err mp_fread(mp_int *a, int radix, FILE *stream)
break;
}
- y = (int)s_mp_rmap_reverse[pos];
+ y = s_mp_rmap_reverse[pos];
if ((y == 0xff) || (y >= radix)) {
break;
@@ -50,7 +50,7 @@ mp_err mp_fread(mp_int *a, int radix, FILE *stream)
if ((err = mp_mul_d(a, (mp_digit)radix, a)) != MP_OKAY) {
return err;
}
- if ((err = mp_add_d(a, (mp_digit)y, a)) != MP_OKAY) {
+ if ((err = mp_add_d(a, y, a)) != MP_OKAY) {
return err;
}
} while ((ch = fgetc(stream)) != EOF);
diff --git a/mp_from_sbin.c b/mp_from_sbin.c
index c6e87d7..3ff7d5d 100644
--- a/mp_from_sbin.c
+++ b/mp_from_sbin.c
@@ -14,11 +14,7 @@ mp_err mp_from_sbin(mp_int *a, const uint8_t *buf, size_t size)
}
/* first byte is 0 for positive, non-zero for negative */
- if (buf[0] == (uint8_t)0) {
- a->sign = MP_ZPOS;
- } else {
- a->sign = MP_NEG;
- }
+ a->sign = (buf[0] == (uint8_t)0) ? MP_ZPOS : MP_NEG;
return MP_OKAY;
}
diff --git a/mp_fwrite.c b/mp_fwrite.c
index be78f7f..42d7287 100644
--- a/mp_fwrite.c
+++ b/mp_fwrite.c
@@ -8,31 +8,24 @@ mp_err mp_fwrite(const mp_int *a, int radix, FILE *stream)
{
char *buf;
mp_err err;
- size_t len, written;
+ size_t size, written;
- /* TODO: this function is not in this PR */
- if ((err = mp_radix_size(a, radix, &len)) != MP_OKAY) {
+ if ((err = mp_radix_size(a, radix, &size)) != MP_OKAY) {
return err;
}
- buf = (char *) MP_MALLOC(len);
+ buf = (char *) MP_MALLOC(size);
if (buf == NULL) {
return MP_MEM;
}
- if ((err = mp_to_radix(a, buf, len, &written, radix)) != MP_OKAY) {
- goto LBL_ERR;
+ if ((err = mp_to_radix(a, buf, size, &written, radix)) == MP_OKAY) {
+ if (fwrite(buf, written, 1uL, stream) != 1uL) {
+ err = MP_ERR;
+ }
}
- if (fwrite(buf, written, 1uL, stream) != 1uL) {
- err = MP_ERR;
- goto LBL_ERR;
- }
- err = MP_OKAY;
-
-
-LBL_ERR:
- MP_FREE_BUFFER(buf, len);
+ MP_FREE_BUFFER(buf, size);
return err;
}
#endif
diff --git a/mp_grow.c b/mp_grow.c
index 3354e59..25be5ed 100644
--- a/mp_grow.c
+++ b/mp_grow.c
@@ -6,9 +6,6 @@
/* grow as required */
mp_err mp_grow(mp_int *a, int size)
{
- int i;
- mp_digit *tmp;
-
/* if the alloc size is smaller alloc more ram */
if (a->alloc < size) {
/* reallocate the array a->dp
@@ -17,21 +14,20 @@ mp_err mp_grow(mp_int *a, int size)
* in case the operation failed we don't want
* to overwrite the dp member of a.
*/
- tmp = (mp_digit *) MP_REALLOC(a->dp,
- (size_t)a->alloc * sizeof(mp_digit),
- (size_t)size * sizeof(mp_digit));
- if (tmp == NULL) {
+ mp_digit *dp = (mp_digit *) MP_REALLOC(a->dp,
+ (size_t)a->alloc * sizeof(mp_digit),
+ (size_t)size * sizeof(mp_digit));
+ if (dp == NULL) {
/* reallocation failed but "a" is still valid [can be freed] */
return MP_MEM;
}
/* reallocation succeeded so set a->dp */
- a->dp = tmp;
+ a->dp = dp;
/* zero excess digits */
- i = a->alloc;
+ MP_ZERO_DIGITS(a->dp + a->alloc, size - a->alloc);
a->alloc = size;
- MP_ZERO_DIGITS(a->dp + i, a->alloc - i);
}
return MP_OKAY;
}
diff --git a/mp_is_square.c b/mp_is_square.c
index f92ecbf..47f8300 100644
--- a/mp_is_square.c
+++ b/mp_is_square.c
@@ -28,10 +28,10 @@ static const char rem_105[105] = {
/* Store non-zero to ret if arg is square, and zero if not */
mp_err mp_is_square(const mp_int *arg, bool *ret)
{
- mp_err err;
- mp_digit c;
- mp_int t;
- unsigned long r;
+ mp_err err;
+ mp_digit c;
+ mp_int t;
+ uint32_t r;
/* Default to Non-square :) */
*ret = false;
diff --git a/mp_kronecker.c b/mp_kronecker.c
index 0ac6338..b106f77 100644
--- a/mp_kronecker.c
+++ b/mp_kronecker.c
@@ -23,7 +23,7 @@ mp_err mp_kronecker(const mp_int *a, const mp_int *p, int *c)
mp_err err;
int v, k;
- static const int table[8] = {0, 1, 0, -1, 0, -1, 0, 1};
+ static const char table[] = {0, 1, 0, -1, 0, -1, 0, 1};
if (mp_iszero(p)) {
if ((a->used == 1) && (a->dp[0] == 1u)) {
diff --git a/mp_lshd.c b/mp_lshd.c
index b0a8454..6c14402 100644
--- a/mp_lshd.c
+++ b/mp_lshd.c
@@ -7,8 +7,6 @@
mp_err mp_lshd(mp_int *a, int b)
{
int x;
- mp_err err;
- mp_digit *top, *bottom;
/* if its less than zero return */
if (b <= 0) {
@@ -21,6 +19,7 @@ mp_err mp_lshd(mp_int *a, int b)
/* grow to fit the new digits */
if (a->alloc < (a->used + b)) {
+ mp_err err;
if ((err = mp_grow(a, a->used + b)) != MP_OKAY) {
return err;
}
@@ -29,18 +28,12 @@ mp_err mp_lshd(mp_int *a, int b)
/* increment the used by the shift amount then copy upwards */
a->used += b;
- /* top */
- top = a->dp + a->used - 1;
-
- /* base */
- bottom = (a->dp + a->used - 1) - b;
-
/* much like mp_rshd this is implemented using a sliding window
* except the window goes the otherway around. Copying from
* the bottom to the top. see mp_rshd.c for more info.
*/
- for (x = a->used - 1; x >= b; x--) {
- *top-- = *bottom--;
+ for (x = a->used; x --> b;) {
+ a->dp[x] = a->dp[x - b];
}
/* zero the lower digits */
diff --git a/mp_mod_2d.c b/mp_mod_2d.c
index 651c79a..a94a314 100644
--- a/mp_mod_2d.c
+++ b/mp_mod_2d.c
@@ -9,8 +9,11 @@ mp_err mp_mod_2d(const mp_int *a, int b, mp_int *c)
int x;
mp_err err;
- /* if b is <= 0 then zero the int */
- if (b <= 0) {
+ if (b < 0) {
+ return MP_VAL;
+ }
+
+ if (b == 0) {
mp_zero(c);
return MP_OKAY;
}
@@ -20,7 +23,6 @@ mp_err mp_mod_2d(const mp_int *a, int b, mp_int *c)
return mp_copy(a, c);
}
- /* copy */
if ((err = mp_copy(a, c)) != MP_OKAY) {
return err;
}
diff --git a/mp_montgomery_calc_normalization.c b/mp_montgomery_calc_normalization.c
index 0d0d5c4..cc07799 100644
--- a/mp_montgomery_calc_normalization.c
+++ b/mp_montgomery_calc_normalization.c
@@ -26,7 +26,6 @@ mp_err mp_montgomery_calc_normalization(mp_int *a, const mp_int *b)
bits = 1;
}
-
/* now compute C = A * B mod b */
for (x = bits - 1; x < (int)MP_DIGIT_BIT; x++) {
if ((err = mp_mul_2(a, a)) != MP_OKAY) {
diff --git a/mp_neg.c b/mp_neg.c
index 2fc1854..f54ef3e 100644
--- a/mp_neg.c
+++ b/mp_neg.c
@@ -6,18 +6,14 @@
/* b = -a */
mp_err mp_neg(const mp_int *a, mp_int *b)
{
- mp_err err;
if (a != b) {
+ mp_err err;
if ((err = mp_copy(a, b)) != MP_OKAY) {
return err;
}
}
- if (!mp_iszero(b)) {
- b->sign = (a->sign == MP_ZPOS) ? MP_NEG : MP_ZPOS;
- } else {
- b->sign = MP_ZPOS;
- }
+ b->sign = mp_iszero(b) || b->sign == MP_NEG ? MP_ZPOS : MP_NEG;
return MP_OKAY;
}
diff --git a/mp_prime_rabin_miller_trials.c b/mp_prime_rabin_miller_trials.c
index 1728142..9f66f8d 100644
--- a/mp_prime_rabin_miller_trials.c
+++ b/mp_prime_rabin_miller_trials.c
@@ -36,7 +36,8 @@ int mp_prime_rabin_miller_trials(int size)
for (x = 0; x < (int)(sizeof(sizes)/(sizeof(sizes[0]))); x++) {
if (sizes[x].k == size) {
return sizes[x].t;
- } else if (sizes[x].k > size) {
+ }
+ if (sizes[x].k > size) {
return (x == 0) ? sizes[0].t : sizes[x - 1].t;
}
}
diff --git a/mp_read_radix.c b/mp_read_radix.c
index d4a3d1e..df8059a 100644
--- a/mp_read_radix.c
+++ b/mp_read_radix.c
@@ -31,13 +31,13 @@ mp_err mp_read_radix(mp_int *a, const char *str, int radix)
* this allows numbers like 1AB and 1ab to represent the same value
* [e.g. in hex]
*/
- int y;
+ uint8_t y;
char ch = (radix <= 36) ? (char)MP_TOUPPER((int)*str) : *str;
unsigned pos = (unsigned)(ch - '(');
if (MP_RMAP_REVERSE_SIZE < pos) {
break;
}
- y = (int)s_mp_rmap_reverse[pos];
+ y = s_mp_rmap_reverse[pos];
/* if the char was found in the map
* and is less than the given radix add it
@@ -49,14 +49,14 @@ mp_err mp_read_radix(mp_int *a, const char *str, int radix)
if ((err = mp_mul_d(a, (mp_digit)radix, a)) != MP_OKAY) {
return err;
}
- if ((err = mp_add_d(a, (mp_digit)y, a)) != MP_OKAY) {
+ if ((err = mp_add_d(a, y, a)) != MP_OKAY) {
return err;
}
++str;
}
/* if an illegal character was found, fail. */
- if (!((*str == '\0') || (*str == '\r') || (*str == '\n'))) {
+ if ((*str != '\0') && (*str != '\r') && (*str != '\n')) {
return MP_VAL;
}
diff --git a/mp_reduce.c b/mp_reduce.c
index 1b4435c..5226fe7 100644
--- a/mp_reduce.c
+++ b/mp_reduce.c
@@ -24,19 +24,19 @@ mp_err mp_reduce(mp_int *x, const mp_int *m, const mp_int *mu)
/* according to HAC this optimization is ok */
if ((mp_digit)um > ((mp_digit)1 << (MP_DIGIT_BIT - 1))) {
if ((err = mp_mul(&q, mu, &q)) != MP_OKAY) {
- goto CLEANUP;
+ goto LBL_ERR;
}
} else if (MP_HAS(S_MP_MUL_HIGH_DIGS)) {
if ((err = s_mp_mul_high_digs(&q, mu, &q, um)) != MP_OKAY) {
- goto CLEANUP;
+ goto LBL_ERR;
}
} else if (MP_HAS(S_MP_MUL_HIGH_DIGS_FAST)) {
if ((err = s_mp_mul_high_digs_fast(&q, mu, &q, um)) != MP_OKAY) {
- goto CLEANUP;
+ goto LBL_ERR;
}
} else {
err = MP_VAL;
- goto CLEANUP;
+ goto LBL_ERR;
}
/* q3 = q2 / b**(k+1) */
@@ -44,38 +44,38 @@ mp_err mp_reduce(mp_int *x, const mp_int *m, const mp_int *mu)
/* x = x mod b**(k+1), quick (no division) */
if ((err = mp_mod_2d(x, MP_DIGIT_BIT * (um + 1), x)) != MP_OKAY) {
- goto CLEANUP;
+ goto LBL_ERR;
}
/* q = q * m mod b**(k+1), quick (no division) */
if ((err = s_mp_mul_digs(&q, m, &q, um + 1)) != MP_OKAY) {
- goto CLEANUP;
+ goto LBL_ERR;
}
/* x = x - q */
if ((err = mp_sub(x, &q, x)) != MP_OKAY) {
- goto CLEANUP;
+ goto LBL_ERR;
}
/* If x < 0, add b**(k+1) to it */
if (mp_cmp_d(x, 0uL) == MP_LT) {
mp_set(&q, 1uL);
if ((err = mp_lshd(&q, um + 1)) != MP_OKAY) {
- goto CLEANUP;
+ goto LBL_ERR;
}
if ((err = mp_add(x, &q, x)) != MP_OKAY) {
- goto CLEANUP;
+ goto LBL_ERR;
}
}
/* Back off if it's too big */
while (mp_cmp(x, m) != MP_LT) {
if ((err = s_mp_sub(x, m, x)) != MP_OKAY) {
- goto CLEANUP;
+ goto LBL_ERR;
}
}
-CLEANUP:
+LBL_ERR:
mp_clear(&q);
return err;
diff --git a/mp_reduce_is_2k.c b/mp_reduce_is_2k.c
index 618ab54..a5798e6 100644
--- a/mp_reduce_is_2k.c
+++ b/mp_reduce_is_2k.c
@@ -6,17 +6,13 @@
/* determines if mp_reduce_2k can be used */
bool mp_reduce_is_2k(const mp_int *a)
{
- int ix, iy, iw;
- mp_digit iz;
-
if (a->used == 0) {
return false;
} else if (a->used == 1) {
return true;
} else if (a->used > 1) {
- iy = mp_count_bits(a);
- iz = 1;
- iw = 1;
+ int ix, iy = mp_count_bits(a), iw = 1;
+ mp_digit iz = 1;
/* Test every bit from the second digit up, must be 1 */
for (ix = MP_DIGIT_BIT; ix < iy; ix++) {
diff --git a/mp_reduce_is_2k_l.c b/mp_reduce_is_2k_l.c
index 30fc10d..dca2d7e 100644
--- a/mp_reduce_is_2k_l.c
+++ b/mp_reduce_is_2k_l.c
@@ -6,14 +6,13 @@
/* determines if reduce_2k_l can be used */
bool mp_reduce_is_2k_l(const mp_int *a)
{
- int ix, iy;
-
if (a->used == 0) {
return false;
} else if (a->used == 1) {
return true;
} else if (a->used > 1) {
/* if more than half of the digits are -1 we're sold */
+ int ix, iy;
for (iy = ix = 0; ix < a->used; ix++) {
if (a->dp[ix] == MP_DIGIT_MAX) {
++iy;
diff --git a/mp_rshd.c b/mp_rshd.c
index 2eabb12..d798907 100644
--- a/mp_rshd.c
+++ b/mp_rshd.c
@@ -6,8 +6,7 @@
/* shift right a certain amount of digits */
void mp_rshd(mp_int *a, int b)
{
- int x;
- mp_digit *bottom, *top;
+ int x;
/* if b <= 0 then ignore it */
if (b <= 0) {
@@ -20,15 +19,8 @@ void mp_rshd(mp_int *a, int b)
return;
}
- /* shift the digits down */
-
- /* bottom */
- bottom = a->dp;
-
- /* top [offset into digits] */
- top = a->dp + b;
-
- /* this is implemented as a sliding window where
+ /* shift the digits down.
+ * this is implemented as a sliding window where
* the window is b-digits long and digits from
* the top of the window are copied to the bottom
*
@@ -39,11 +31,11 @@ void mp_rshd(mp_int *a, int b)
\-------------------/ ---->
*/
for (x = 0; x < (a->used - b); x++) {
- *bottom++ = *top++;
+ a->dp[x] = a->dp[x + b];
}
/* zero the top digits */
- MP_ZERO_DIGITS(bottom, a->used - x);
+ MP_ZERO_DIGITS(a->dp + a->used - b, b);
/* remove excess digits */
a->used -= b;
diff --git a/mp_set.c b/mp_set.c
index 0777f09..3ee5f81 100644
--- a/mp_set.c
+++ b/mp_set.c
@@ -6,9 +6,10 @@
/* set to a digit */
void mp_set(mp_int *a, mp_digit b)
{
+ int oldused = a->used;
a->dp[0] = b & MP_MASK;
a->sign = MP_ZPOS;
a->used = (a->dp[0] != 0u) ? 1 : 0;
- MP_ZERO_DIGITS(a->dp + a->used, a->alloc - a->used);
+ MP_ZERO_DIGITS(a->dp + a->used, oldused - a->used);
}
#endif
diff --git a/mp_shrink.c b/mp_shrink.c
index 6c3c95b..e5814cb 100644
--- a/mp_shrink.c
+++ b/mp_shrink.c
@@ -6,15 +6,15 @@
/* shrink a bignum */
mp_err mp_shrink(mp_int *a)
{
- mp_digit *tmp;
int alloc = MP_MAX(MP_MIN_PREC, a->used);
if (a->alloc != alloc) {
- if ((tmp = (mp_digit *) MP_REALLOC(a->dp,
- (size_t)a->alloc * sizeof(mp_digit),
- (size_t)alloc * sizeof(mp_digit))) == NULL) {
+ mp_digit *dp = (mp_digit *) MP_REALLOC(a->dp,
+ (size_t)a->alloc * sizeof(mp_digit),
+ (size_t)alloc * sizeof(mp_digit));
+ if (dp == NULL) {
return MP_MEM;
}
- a->dp = tmp;
+ a->dp = dp;
a->alloc = alloc;
}
return MP_OKAY;
diff --git a/mp_signed_rsh.c b/mp_signed_rsh.c
index c56dfba..ecaaa21 100644
--- a/mp_signed_rsh.c
+++ b/mp_signed_rsh.c
@@ -6,17 +6,16 @@
/* shift right by a certain bit count with sign extension */
mp_err mp_signed_rsh(const mp_int *a, int b, mp_int *c)
{
- mp_err res;
+ mp_err err;
if (a->sign == MP_ZPOS) {
return mp_div_2d(a, b, c, NULL);
}
- res = mp_add_d(a, 1uL, c);
- if (res != MP_OKAY) {
- return res;
+ if ((err = mp_add_d(a, 1uL, c)) != MP_OKAY) {
+ return err;
}
- res = mp_div_2d(c, b, c, NULL);
- return (res == MP_OKAY) ? mp_sub_d(c, 1uL, c) : res;
+ err = mp_div_2d(c, b, c, NULL);
+ return (err == MP_OKAY) ? mp_sub_d(c, 1uL, c) : err;
}
#endif
diff --git a/mp_sqrt.c b/mp_sqrt.c
index b51f615..e36a81a 100644
--- a/mp_sqrt.c
+++ b/mp_sqrt.c
@@ -25,7 +25,7 @@ mp_err mp_sqrt(const mp_int *arg, mp_int *ret)
}
if ((err = mp_init(&t2)) != MP_OKAY) {
- goto E2;
+ goto LBL_ERR2;
}
/* First approx. (not very bad for large arg) */
@@ -33,33 +33,33 @@ mp_err mp_sqrt(const mp_int *arg, mp_int *ret)
/* t1 > 0 */
if ((err = mp_div(arg, &t1, &t2, NULL)) != MP_OKAY) {
- goto E1;
+ goto LBL_ERR1;
}
if ((err = mp_add(&t1, &t2, &t1)) != MP_OKAY) {
- goto E1;
+ goto LBL_ERR1;
}
if ((err = mp_div_2(&t1, &t1)) != MP_OKAY) {
- goto E1;
+ goto LBL_ERR1;
}
/* And now t1 > sqrt(arg) */
do {
if ((err = mp_div(arg, &t1, &t2, NULL)) != MP_OKAY) {
- goto E1;
+ goto LBL_ERR1;
}
if ((err = mp_add(&t1, &t2, &t1)) != MP_OKAY) {
- goto E1;
+ goto LBL_ERR1;
}
if ((err = mp_div_2(&t1, &t1)) != MP_OKAY) {
- goto E1;
+ goto LBL_ERR1;
}
/* t1 >= sqrt(arg) >= t2 at this point */
} while (mp_cmp_mag(&t1, &t2) == MP_GT);
mp_exch(&t1, ret);
-E1:
+LBL_ERR1:
mp_clear(&t2);
-E2:
+LBL_ERR2:
mp_clear(&t1);
return err;
}
diff --git a/mp_sqrtmod_prime.c b/mp_sqrtmod_prime.c
index 96b2836..8930184 100644
--- a/mp_sqrtmod_prime.c
+++ b/mp_sqrtmod_prime.c
@@ -33,28 +33,28 @@ mp_err mp_sqrtmod_prime(const mp_int *n, const mp_int *prime, mp_int *ret)
* compute directly: err = n^(prime+1)/4 mod prime
* Handbook of Applied Cryptography algorithm 3.36
*/
- if ((err = mp_mod_d(prime, 4uL, &i)) != MP_OKAY) goto cleanup;
+ if ((err = mp_mod_d(prime, 4uL, &i)) != MP_OKAY) goto LBL_END;
if (i == 3u) {
- if ((err = mp_add_d(prime, 1uL, &t1)) != MP_OKAY) goto cleanup;
- if ((err = mp_div_2(&t1, &t1)) != MP_OKAY) goto cleanup;
- if ((err = mp_div_2(&t1, &t1)) != MP_OKAY) goto cleanup;
- if ((err = mp_exptmod(n, &t1, prime, ret)) != MP_OKAY) goto cleanup;
+ if ((err = mp_add_d(prime, 1uL, &t1)) != MP_OKAY) goto LBL_END;
+ if ((err = mp_div_2(&t1, &t1)) != MP_OKAY) goto LBL_END;
+ if ((err = mp_div_2(&t1, &t1)) != MP_OKAY) goto LBL_END;
+ if ((err = mp_exptmod(n, &t1, prime, ret)) != MP_OKAY) goto LBL_END;
err = MP_OKAY;
- goto cleanup;
+ goto LBL_END;
}
/* NOW: Tonelli-Shanks algorithm */
/* factor out powers of 2 from prime-1, defining Q and S as: prime-1 = Q*2^S */
- if ((err = mp_copy(prime, &Q)) != MP_OKAY) goto cleanup;
- if ((err = mp_sub_d(&Q, 1uL, &Q)) != MP_OKAY) goto cleanup;
+ if ((err = mp_copy(prime, &Q)) != MP_OKAY) goto LBL_END;
+ if ((err = mp_sub_d(&Q, 1uL, &Q)) != MP_OKAY) goto LBL_END;
/* Q = prime - 1 */
mp_zero(&S);
/* S = 0 */
while (mp_iseven(&Q)) {
- if ((err = mp_div_2(&Q, &Q)) != MP_OKAY) goto cleanup;
+ if ((err = mp_div_2(&Q, &Q)) != MP_OKAY) goto LBL_END;
/* Q = Q / 2 */
- if ((err = mp_add_d(&S, 1uL, &S)) != MP_OKAY) goto cleanup;
+ if ((err = mp_add_d(&S, 1uL, &S)) != MP_OKAY) goto LBL_END;
/* S = S + 1 */
}
@@ -62,55 +62,55 @@ mp_err mp_sqrtmod_prime(const mp_int *n, const mp_int *prime, mp_int *ret)
mp_set(&Z, 2uL);
/* Z = 2 */
for (;;) {
- if ((err = mp_kronecker(&Z, prime, &legendre)) != MP_OKAY) goto cleanup;
+ if ((err = mp_kronecker(&Z, prime, &legendre)) != MP_OKAY) goto LBL_END;
if (legendre == -1) break;
- if ((err = mp_add_d(&Z, 1uL, &Z)) != MP_OKAY) goto cleanup;
+ if ((err = mp_add_d(&Z, 1uL, &Z)) != MP_OKAY) goto LBL_END;
/* Z = Z + 1 */
}
- if ((err = mp_exptmod(&Z, &Q, prime, &C)) != MP_OKAY) goto cleanup;
+ if ((err = mp_exptmod(&Z, &Q, prime, &C)) != MP_OKAY) goto LBL_END;
/* C = Z ^ Q mod prime */
- if ((err = mp_add_d(&Q, 1uL, &t1)) != MP_OKAY) goto cleanup;
- if ((err = mp_div_2(&t1, &t1)) != MP_OKAY) goto cleanup;
+ if ((err = mp_add_d(&Q, 1uL, &t1)) != MP_OKAY) goto LBL_END;
+ if ((err = mp_div_2(&t1, &t1)) != MP_OKAY) goto LBL_END;
/* t1 = (Q + 1) / 2 */
- if ((err = mp_exptmod(n, &t1, prime, &R)) != MP_OKAY) goto cleanup;
+ if ((err = mp_exptmod(n, &t1, prime, &R)) != MP_OKAY) goto LBL_END;
/* R = n ^ ((Q + 1) / 2) mod prime */
- if ((err = mp_exptmod(n, &Q, prime, &T)) != MP_OKAY) goto cleanup;
+ if ((err = mp_exptmod(n, &Q, prime, &T)) != MP_OKAY) goto LBL_END;
/* T = n ^ Q mod prime */
- if ((err = mp_copy(&S, &M)) != MP_OKAY) goto cleanup;
+ if ((err = mp_copy(&S, &M)) != MP_OKAY) goto LBL_END;
/* M = S */
mp_set(&two, 2uL);
for (;;) {
- if ((err = mp_copy(&T, &t1)) != MP_OKAY) goto cleanup;
+ if ((err = mp_copy(&T, &t1)) != MP_OKAY) goto LBL_END;
i = 0;
for (;;) {
if (mp_cmp_d(&t1, 1uL) == MP_EQ) break;
- if ((err = mp_exptmod(&t1, &two, prime, &t1)) != MP_OKAY) goto cleanup;
+ if ((err = mp_exptmod(&t1, &two, prime, &t1)) != MP_OKAY) goto LBL_END;
i++;
}
if (i == 0u) {
- if ((err = mp_copy(&R, ret)) != MP_OKAY) goto cleanup;
+ if ((err = mp_copy(&R, ret)) != MP_OKAY) goto LBL_END;
err = MP_OKAY;
- goto cleanup;
+ goto LBL_END;
}
- if ((err = mp_sub_d(&M, i, &t1)) != MP_OKAY) goto cleanup;
- if ((err = mp_sub_d(&t1, 1uL, &t1)) != MP_OKAY) goto cleanup;
- if ((err = mp_exptmod(&two, &t1, prime, &t1)) != MP_OKAY) goto cleanup;
+ if ((err = mp_sub_d(&M, i, &t1)) != MP_OKAY) goto LBL_END;
+ if ((err = mp_sub_d(&t1, 1uL, &t1)) != MP_OKAY) goto LBL_END;
+ if ((err = mp_exptmod(&two, &t1, prime, &t1)) != MP_OKAY) goto LBL_END;
/* t1 = 2 ^ (M - i - 1) */
- if ((err = mp_exptmod(&C, &t1, prime, &t1)) != MP_OKAY) goto cleanup;
+ if ((err = mp_exptmod(&C, &t1, prime, &t1)) != MP_OKAY) goto LBL_END;
/* t1 = C ^ (2 ^ (M - i - 1)) mod prime */
- if ((err = mp_sqrmod(&t1, prime, &C)) != MP_OKAY) goto cleanup;
+ if ((err = mp_sqrmod(&t1, prime, &C)) != MP_OKAY) goto LBL_END;
/* C = (t1 * t1) mod prime */
- if ((err = mp_mulmod(&R, &t1, prime, &R)) != MP_OKAY) goto cleanup;
+ if ((err = mp_mulmod(&R, &t1, prime, &R)) != MP_OKAY) goto LBL_END;
/* R = (R * t1) mod prime */
- if ((err = mp_mulmod(&T, &C, prime, &T)) != MP_OKAY) goto cleanup;
+ if ((err = mp_mulmod(&T, &C, prime, &T)) != MP_OKAY) goto LBL_END;
/* T = (T * C) mod prime */
mp_set(&M, i);
/* M = i */
}
-cleanup:
+LBL_END:
mp_clear_multi(&t1, &C, &Q, &S, &Z, &M, &T, &R, &two, NULL);
return err;
}
diff --git a/mp_sub.c b/mp_sub.c
index c859026..8104740 100644
--- a/mp_sub.c
+++ b/mp_sub.c
@@ -6,35 +6,31 @@
/* high level subtraction (handles signs) */
mp_err mp_sub(const mp_int *a, const mp_int *b, mp_int *c)
{
- mp_sign sa = a->sign, sb = b->sign;
- mp_err err;
-
- if (sa != sb) {
+ if (a->sign != b->sign) {
/* subtract a negative from a positive, OR */
/* subtract a positive from a negative. */
/* In either case, ADD their magnitudes, */
/* and use the sign of the first number. */
- c->sign = sa;
- err = s_mp_add(a, b, c);
+ c->sign = a->sign;
+ return s_mp_add(a, b, c);
+ }
+
+ /* subtract a positive from a positive, OR */
+ /* subtract a negative from a negative. */
+ /* First, take the difference between their */
+ /* magnitudes, then... */
+ if (mp_cmp_mag(a, b) == MP_LT) {
+ /* The second has a larger magnitude */
+ /* The result has the *opposite* sign from */
+ /* the first number. */
+ c->sign = (a->sign == MP_ZPOS) ? MP_NEG : MP_ZPOS;
+ MP_EXCH(const mp_int *, a, b);
} else {
- /* subtract a positive from a positive, OR */
- /* subtract a negative from a negative. */
- /* First, take the difference between their */
- /* magnitudes, then... */
- if (mp_cmp_mag(a, b) != MP_LT) {
- /* Copy the sign from the first */
- c->sign = sa;
- /* The first has a larger or equal magnitude */
- err = s_mp_sub(a, b, c);
- } else {
- /* The result has the *opposite* sign from */
- /* the first number. */
- c->sign = (sa == MP_ZPOS) ? MP_NEG : MP_ZPOS;
- /* The second has a larger magnitude */
- err = s_mp_sub(b, a, c);
- }
+ /* The first has a larger or equal magnitude */
+ /* Copy the sign from the first */
+ c->sign = a->sign;
}
- return err;
+ return s_mp_sub(a, b, c);
}
#endif
diff --git a/mp_to_radix.c b/mp_to_radix.c
index c1ea233..8b7728d 100644
--- a/mp_to_radix.c
+++ b/mp_to_radix.c
@@ -4,17 +4,11 @@
/* SPDX-License-Identifier: Unlicense */
/* reverse an array, used for radix code */
-static void s_mp_reverse(uint8_t *s, size_t len)
+static void s_mp_reverse(char *s, size_t len)
{
- size_t ix, iy;
- uint8_t t;
-
- ix = 0u;
- iy = len - 1u;
+ size_t ix = 0, iy = len - 1u;
while (ix < iy) {
- t = s[ix];
- s[ix] = s[iy];
- s[iy] = t;
+ MP_EXCH(char, s[ix], s[iy]);
++ix;
--iy;
}
@@ -83,7 +77,7 @@ mp_err mp_to_radix(const mp_int *a, char *str, size_t maxlen, size_t *written, i
/* reverse the digits of the string. In this case _s points
* to the first digit [exluding the sign] of the number
*/
- s_mp_reverse((uint8_t *)_s, digs);
+ s_mp_reverse(_s, digs);
/* append a NULL so the string is properly terminated */
*str = '\0';
diff --git a/mp_zero.c b/mp_zero.c
index 0b79f50..b7dddd2 100644
--- a/mp_zero.c
+++ b/mp_zero.c
@@ -7,7 +7,7 @@
void mp_zero(mp_int *a)
{
a->sign = MP_ZPOS;
+ MP_ZERO_DIGITS(a->dp, a->used);
a->used = 0;
- MP_ZERO_DIGITS(a->dp, a->alloc);
}
#endif
diff --git a/s_mp_div_recursive.c b/s_mp_div_recursive.c
index d641123..7007aef 100644
--- a/s_mp_div_recursive.c
+++ b/s_mp_div_recursive.c
@@ -17,10 +17,9 @@
static mp_err s_mp_recursion(const mp_int *a, const mp_int *b, mp_int *q, mp_int *r)
{
mp_err err;
- int m, k;
mp_int A1, A2, B1, B0, Q1, Q0, R1, R0, t;
+ int m = a->used - b->used, k = m/2;
- m = a->used - b->used;
if (m < MP_KARATSUBA_MUL_CUTOFF) {
return s_mp_div_school(a, b, q, r);
}
@@ -29,9 +28,6 @@ static mp_err s_mp_recursion(const mp_int *a, const mp_int *b, mp_int *q, mp_int
goto LBL_ERR;
}
- /* k = floor(m/2) */
- k = m/2;
-
/* B1 = b / beta^k, B0 = b % beta^k*/
if ((err = mp_div_2d(b, k * MP_DIGIT_BIT, &B1, &B0)) != MP_OKAY) goto LBL_ERR;
diff --git a/s_mp_div_school.c b/s_mp_div_school.c
index 6ff427a..cf34cc9 100644
--- a/s_mp_div_school.c
+++ b/s_mp_div_school.c
@@ -140,8 +140,6 @@ mp_err s_mp_div_school(const mp_int *a, const mp_int *b, mp_int *c, mp_int *d)
mp_exch(&x, d);
}
- err = MP_OKAY;
-
LBL_Y:
mp_clear(&y);
LBL_X:
diff --git a/tommath_private.h b/tommath_private.h
index 0f5ac93..31f1ea5 100644
--- a/tommath_private.h
+++ b/tommath_private.h
@@ -148,6 +148,8 @@ extern void MP_FREE(void *mem, size_t size);
#define MP_TOUPPER(c) ((((c) >= 'a') && ((c) <= 'z')) ? (((c) + 'A') - 'a') : (c))
+#define MP_EXCH(t, a, b) do { t _c = a; a = b; b = _c; } while (0)
+
/* Static assertion */
#define MP_STATIC_ASSERT(msg, cond) typedef char mp_static_assert_##msg[(cond) ? 1 : -1];
@@ -267,9 +269,9 @@ extern MP_PRIVATE const mp_digit s_mp_prime_tab[];
#define MP_GET_MAG(name, type) \
type name(const mp_int* a) \
{ \
- unsigned i = MP_MIN((unsigned)a->used, (unsigned)((MP_SIZEOF_BITS(type) + MP_DIGIT_BIT - 1) / MP_DIGIT_BIT)); \
+ int i = MP_MIN(a->used, (int)((MP_SIZEOF_BITS(type) + MP_DIGIT_BIT - 1) / MP_DIGIT_BIT)); \
type res = 0u; \
- while (i --> 0u) { \
+ while (i --> 0) { \
res <<= ((MP_SIZEOF_BITS(type) <= MP_DIGIT_BIT) ? 0 : MP_DIGIT_BIT); \
res |= (type)a->dp[i]; \
if (MP_SIZEOF_BITS(type) <= MP_DIGIT_BIT) { break; } \