Merge remote-tracking branch 'remotes/original/master' into develop

.gitattributes

@@ -1,4 +1,5 @@
 /.gitattributes export-ignore
 /.gitignore     export-ignore
+/.travis.yml    export-ignore
 
 /**             export-subst

.gitignore

@@ -6,16 +6,18 @@
 *.gcno
 *.gcov
 *.lib
-Debug/
+[Dd]ebug/
-Release/
+[Rr]elease/
+/MSVC_*
 .libs/
 .coveralls.yml
 coverage*/
 coverage.info
+pre_gen/*
 
 # suppress output of build process and *nix/windows test executables
-ltmtest
+timing
-ltmtest.exe
+timing.exe
 test
 test.exe
 mtest
@@ -31,6 +33,25 @@ mtest.exe
 # ignore user specific settings
 *.user
 *.suo
+*.userosscache
+*.sln.docstates
+*.userprefs
+# cache/options directory
+.vs/
+# Backup & report files from converting an old project file to a newer Visual Studio version
+_UpgradeReport_Files/
+Backup*/
+UpgradeLog*.XML
+UpgradeLog*.htm
+# Visual Studio 6 build log + workspace options file
+*.plg
+*.opt
+# visual studio profiler
+*.psess
+*.vsp
+*.vspx
+*.sap
+
 
 # ignore stuff generated by "make manual" and "make poster"
 *.aux
@@ -56,7 +77,3 @@ test_*.txt
 *.asc
 *.tar.xz
 *.zip
-
-.idea/
-cmake-build-*/
-out/

.travis.yml

@@ -1,18 +1,35 @@
 language: c
-compiler:
-  - gcc
 
-script:
+install:
-  - make travis_mtest
+    - sudo apt-get update -qq
-  - head -n 5 test.log
+    - sudo apt-get install gcc-multilib
-  - tail -n 2 test.log
-  - ./testme.sh --with-cc=gcc --with-low-mp
 
+matrix:
+  fast_finish: true
 branches:
   only:
     - master
     - develop
     - /^release\/.*$/
 
+compiler:
+  - gcc
+  - clang
+script:
+  - ./testme.sh --with-cc=$CC ${BUILDOPTIONS}
+env:
+  - |
+    BUILDOPTIONS="--test-vs-mtest=333333"
+  - |
+    BUILDOPTIONS="--test-vs-mtest=333333 --mtest-real-rand"
+  - |
+    BUILDOPTIONS="--with-low-mp"
+  - |
+    BUILDOPTIONS="--with-m64 --with-m32 --with-mx32"
+
+after_failure:
+  - cat test_*.log
+  - cat gcc_errors_*.log
+
 notifications:
   irc: "chat.freenode.net#libtom-notifications"

CMakeLists.txt

@@ -1,166 +1,21 @@
 cmake_minimum_required(VERSION 3.6)
-project(libtommath)
+project(libtommath C)
 
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 
-set(SOURCE_FILES
+file(GLOB SOURCE_FILES ./bn*.c)
-#    demo/demo.c
+list(APPEND SOURCE_FILES
-#    demo/timing.c
-#    etc/2kprime.c
-#    etc/drprime.c
-#    etc/makefile.icc
-#    etc/mersenne.c
-#    etc/mont.c
-#    etc/pprime.c
-#    etc/tune.c
-#    mtest/logtab.h
-#    mtest/mpi-config.h
-#    mtest/mpi-types.h
-#    mtest/mpi.c
-#    mtest/mpi.h
-#    mtest/mtest.c
-#    pre_gen/mpi.c
-    bn_error.c
-    bn_fast_mp_invmod.c
-    bn_fast_mp_montgomery_reduce.c
-    bn_fast_s_mp_mul_digs.c
-    bn_fast_s_mp_mul_high_digs.c
-    bn_fast_s_mp_sqr.c
-    bn_mp_2expt.c
-    bn_mp_abs.c
-    bn_mp_add.c
-    bn_mp_add_d.c
-    bn_mp_addmod.c
-    bn_mp_and.c
-    bn_mp_clamp.c
-    bn_mp_clear.c
-    bn_mp_clear_multi.c
-    bn_mp_cmp.c
-    bn_mp_cmp_d.c
-    bn_mp_cmp_mag.c
-    bn_mp_cnt_lsb.c
-    bn_mp_copy.c
-    bn_mp_count_bits.c
-    bn_mp_div.c
-    bn_mp_div_2.c
-    bn_mp_div_2d.c
-    bn_mp_div_3.c
-    bn_mp_div_d.c
-    bn_mp_dr_is_modulus.c
-    bn_mp_dr_reduce.c
-    bn_mp_dr_setup.c
-    bn_mp_exch.c
-    bn_mp_export.c
-    bn_mp_expt_d.c
-    bn_mp_expt_d_ex.c
-    bn_mp_exptmod.c
-    bn_mp_exptmod_fast.c
-    bn_mp_exteuclid.c
-    bn_mp_fread.c
-    bn_mp_fwrite.c
-    bn_mp_gcd.c
-    bn_mp_get_int.c
-    bn_mp_get_long.c
-    bn_mp_get_long_long.c
-    bn_mp_grow.c
-    bn_mp_import.c
-    bn_mp_init.c
-    bn_mp_init_copy.c
-    bn_mp_init_multi.c
-    bn_mp_init_set.c
-    bn_mp_init_set_int.c
-    bn_mp_init_size.c
-    bn_mp_invmod.c
-    bn_mp_invmod_slow.c
-    bn_mp_is_square.c
-    bn_mp_jacobi.c
-    bn_mp_karatsuba_mul.c
-    bn_mp_karatsuba_sqr.c
-    bn_mp_lcm.c
-    bn_mp_lshd.c
-    bn_mp_mod.c
-    bn_mp_mod_2d.c
-    bn_mp_mod_d.c
-    bn_mp_montgomery_calc_normalization.c
-    bn_mp_montgomery_reduce.c
-    bn_mp_montgomery_setup.c
-    bn_mp_mul.c
-    bn_mp_mul_2.c
-    bn_mp_mul_2d.c
-    bn_mp_mul_d.c
-    bn_mp_mulmod.c
-    bn_mp_n_root.c
-    bn_mp_n_root_ex.c
-    bn_mp_neg.c
-    bn_mp_or.c
-    bn_mp_prime_fermat.c
-    bn_mp_prime_is_divisible.c
-    bn_mp_prime_is_prime.c
-    bn_mp_prime_miller_rabin.c
-    bn_mp_prime_next_prime.c
-    bn_mp_prime_rabin_miller_trials.c
-    bn_mp_prime_random_ex.c
-    bn_mp_radix_size.c
-    bn_mp_radix_smap.c
-    bn_mp_rand.c
-    bn_mp_read_radix.c
-    bn_mp_read_signed_bin.c
-    bn_mp_read_unsigned_bin.c
-    bn_mp_reduce.c
-    bn_mp_reduce_2k.c
-    bn_mp_reduce_2k_l.c
-    bn_mp_reduce_2k_setup.c
-    bn_mp_reduce_2k_setup_l.c
-    bn_mp_reduce_is_2k.c
-    bn_mp_reduce_is_2k_l.c
-    bn_mp_reduce_setup.c
-    bn_mp_rshd.c
-    bn_mp_set.c
-    bn_mp_set_int.c
-    bn_mp_set_long.c
-    bn_mp_set_long_long.c
-    bn_mp_shrink.c
-    bn_mp_signed_bin_size.c
-    bn_mp_sqr.c
-    bn_mp_sqrmod.c
-    bn_mp_sqrt.c
-    bn_mp_sqrtmod_prime.c
-    bn_mp_sub.c
-    bn_mp_sub_d.c
-    bn_mp_submod.c
-    bn_mp_to_signed_bin.c
-    bn_mp_to_signed_bin_n.c
-    bn_mp_to_unsigned_bin.c
-    bn_mp_to_unsigned_bin_n.c
-    bn_mp_toom_mul.c
-    bn_mp_toom_sqr.c
-    bn_mp_toradix.c
-    bn_mp_toradix_n.c
-    bn_mp_unsigned_bin_size.c
-    bn_mp_xor.c
-    bn_mp_zero.c
-    bn_prime_tab.c
-    bn_reverse.c
-    bn_s_mp_add.c
-    bn_s_mp_exptmod.c
-    bn_s_mp_mul_digs.c
-    bn_s_mp_mul_high_digs.c
-    bn_s_mp_sqr.c
-    bn_s_mp_sub.c
-    bncore.c
-    makefile.icc
     tommath.h
     tommath_class.h
     tommath_private.h
-    tommath_superclass.h)
+    tommath_superclass.h
-
+)
-add_definitions(-DALL_FUNCTIONS)
 
 add_library(tommathShared SHARED ${SOURCE_FILES})
 add_library(tommathStatic STATIC ${SOURCE_FILES})
 
 # Install library
-install(TARGETS tommathShared DESTINATION lib/)
+install(TARGETS tommathStatic tommathShared DESTINATION lib/)
 # Install library headers
 file(GLOB HEADERS *.h)
 install(FILES ${HEADERS} DESTINATION include/)

LICENSE

@@ -1,29 +1,26 @@
-LibTomMath is licensed under DUAL licensing terms.
+                          The LibTom license
 
-Choose and use the license of your needs.
+This is free and unencumbered software released into the public domain.
 
-[LICENSE #1]
+Anyone is free to copy, modify, publish, use, compile, sell, or
+distribute this software, either in source code form or as a compiled
+binary, for any purpose, commercial or non-commercial, and by any
+means.
 
-LibTomMath is public domain.  As should all quality software be.
+In jurisdictions that recognize copyright laws, the author or authors
+of this software dedicate any and all copyright interest in the
+software to the public domain. We make this dedication for the benefit
+of the public at large and to the detriment of our heirs and
+successors. We intend this dedication to be an overt act of
+relinquishment in perpetuity of all present and future rights to this
+software under copyright law.
 
-Tom St Denis
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
 
-[/LICENSE #1]
+For more information, please refer to <http://unlicense.org/>
-
-[LICENSE #2]
-
-            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
-                    Version 2, December 2004
-
- Copyright (C) 2004 Sam Hocevar <sam@hocevar.net>
-
- Everyone is permitted to copy and distribute verbatim or modified
- copies of this license document, and changing it is allowed as long
- as the name is changed.
-
-            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
-   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
-
-  0. You just DO WHAT THE FUCK YOU WANT TO. 
-
-[/LICENSE #2]

README.md

@@ -1,8 +1,16 @@
-[![Build Status - master](https://travis-ci.org/libtom/libtommath.png?branch=master)](https://travis-ci.org/libtom/libtommath)
+# libtommath
 
-[![Build Status - develop](https://travis-ci.org/libtom/libtommath.png?branch=develop)](https://travis-ci.org/libtom/libtommath)
+This is the git repository for [LibTomMath](http://www.libtom.net/LibTomMath/), a free open source portable number theoretic multiple-precision integer (MPI) library written entirely in C.
 
-This is the git repository for [LibTomMath](http://www.libtom.org/), a free open source portable number theoretic multiple-precision integer (MPI) library written entirely in C.
+## Build Status
+
+master: [![Build Status](https://api.travis-ci.org/libtom/libtommath.png?branch=master)](https://travis-ci.org/libtom/libtommath)
+
+develop: [![Build Status](https://api.travis-ci.org/libtom/libtommath.png?branch=develop)](https://travis-ci.org/libtom/libtommath)
+
+API/ABI changes: [check here](https://abi-laboratory.pro/tracker/timeline/libtommath/)
+
+## Summary
 
 The `develop` branch contains the in-development version. Stable releases are tagged.
 
@@ -10,6 +18,8 @@ Documentation is built from the LaTeX file `bn.tex`. There is also limited docum
 
 The project can be build by using `make`. Along with the usual `make`, `make clean` and `make install`, there are several other build targets, see the makefile for details. There are also makefiles for certain specific platforms.
 
+## Testing
+
 Tests are located in `demo/` and can be built in two flavors.
 * `make test` creates a test binary that is intended to be run against `mtest`. `mtest` can be built with `make mtest` and test execution is done like `./mtest/mtest | ./test`. `mtest` is creating test vectors using an alternative MPI library and `test` is consuming these vectors to verify correct behavior of ltm
 * `make test_standalone` creates a stand-alone test binary that executes several test routines.

bn_error.c

@@ -1,6 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-
+#ifdef BN_ERROR_C
-#if defined(ALL_FUNCTIONS) || defined(BN_ERROR_C)
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -10,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 static const struct {
@@ -28,10 +24,10 @@ static const struct {
 /* return a char * string for a given code */
 const char *mp_error_to_string(int code)
 {
-   int x;
+   size_t x;
 
    /* scan the lookup table for the given message */
-   for (x = 0; x < (int)(sizeof(msgs) / sizeof(msgs[0])); x++) {
+   for (x = 0; x < (sizeof(msgs) / sizeof(msgs[0])); x++) {
       if (msgs[x].code == code) {
          return msgs[x].msg;
       }

bn_fast_mp_invmod.c

@@ -1,6 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-
+#ifdef BN_FAST_MP_INVMOD_C
-#if defined(ALL_FUNCTIONS) || defined(BN_FAST_MP_INVMOD_C)
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -10,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* computes the modular inverse via binary extended euclidean algorithm,
@@ -47,6 +43,12 @@ int fast_mp_invmod(const mp_int *a, const mp_int *b, mp_int *c)
       goto LBL_ERR;
    }
 
+   /* if one of x,y is zero return an error! */
+   if ((mp_iszero(&x) == MP_YES) || (mp_iszero(&y) == MP_YES)) {
+      res = MP_VAL;
+      goto LBL_ERR;
+   }
+
    /* 3. u=x, v=y, A=1, B=0, C=0,D=1 */
    if ((res = mp_copy(&x, &u)) != MP_OKAY) {
       goto LBL_ERR;
@@ -54,7 +56,7 @@ int fast_mp_invmod(const mp_int *a, const mp_int *b, mp_int *c)
    if ((res = mp_copy(&y, &v)) != MP_OKAY) {
       goto LBL_ERR;
    }
-   mp_set(&D, 1);
+   mp_set(&D, 1uL);
 
 top:
    /* 4.  while u is even do */
@@ -123,7 +125,7 @@ top:
    /* now a = C, b = D, gcd == g*v */
 
    /* if v != 1 then there is no inverse */
-   if (mp_cmp_d(&v, 1) != MP_EQ) {
+   if (mp_cmp_d(&v, 1uL) != MP_EQ) {
       res = MP_VAL;
       goto LBL_ERR;
    }
@@ -135,6 +137,14 @@ top:
          goto LBL_ERR;
       }
    }
+
+   /* too big */
+   while (mp_cmp_mag(&D, b) != MP_LT) {
+      if ((res = mp_sub(&D, b, &D)) != MP_OKAY) {
+         goto LBL_ERR;
+      }
+   }
+
    mp_exch(&D, c);
    c->sign = neg;
    res = MP_OKAY;

bn_fast_mp_montgomery_reduce.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_FAST_MP_MONTGOMERY_REDUCE_C)
+#ifdef BN_FAST_MP_MONTGOMERY_REDUCE_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* computes xR**-1 == x (mod N) via Montgomery Reduction
@@ -28,6 +25,10 @@ int fast_mp_montgomery_reduce(mp_int *x, const mp_int *n, mp_digit rho)
    int     ix, res, olduse;
    mp_word W[MP_WARRAY];
 
+   if (x->used > (int)MP_WARRAY) {
+      return MP_VAL;
+   }
+
    /* get old used count */
    olduse = x->used;
 
@@ -73,7 +74,7 @@ int fast_mp_montgomery_reduce(mp_int *x, const mp_int *n, mp_digit rho)
        * that W[ix-1] have  the carry cleared (see after the inner loop)
        */
       mp_digit mu;
-      mu = (mp_digit)(((W[ix] & MP_MASK) * rho) & MP_MASK);
+      mu = ((W[ix] & MP_MASK) * rho) & MP_MASK;
 
       /* a = a + mu * m * b**i
        *
@@ -102,12 +103,12 @@ int fast_mp_montgomery_reduce(mp_int *x, const mp_int *n, mp_digit rho)
 
          /* inner loop */
          for (iy = 0; iy < n->used; iy++) {
-            *_W++ += ((mp_word)mu) * ((mp_word)*tmpn++);
+            *_W++ += (mp_word)mu * (mp_word)*tmpn++;
          }
       }
 
       /* now fix carry for next digit, W[ix+1] */
-      W[ix + 1] += W[ix] >> ((mp_word) DIGIT_BIT);
+      W[ix + 1] += W[ix] >> (mp_word)DIGIT_BIT;
    }
 
    /* now we have to propagate the carries and
@@ -127,7 +128,7 @@ int fast_mp_montgomery_reduce(mp_int *x, const mp_int *n, mp_digit rho)
       _W = W + ++ix;
 
       for (; ix <= ((n->used * 2) + 1); ix++) {
-         *_W++ += *_W1++ >> ((mp_word) DIGIT_BIT);
+         *_W++ += *_W1++ >> (mp_word)DIGIT_BIT;
       }
 
       /* copy out, A = A/b**n
@@ -144,7 +145,7 @@ int fast_mp_montgomery_reduce(mp_int *x, const mp_int *n, mp_digit rho)
       _W = W + n->used;
 
       for (ix = 0; ix < (n->used + 1); ix++) {
-         *tmpx++ = (mp_digit)(*_W++ & ((mp_word) MP_MASK));
+         *tmpx++ = *_W++ & (mp_word)MP_MASK;
       }
 
       /* zero oldused digits, if the input a was larger than

bn_fast_s_mp_mul_digs.c

@@ -1,6 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-
+#ifdef BN_FAST_S_MP_MUL_DIGS_C
-#if defined(ALL_FUNCTIONS) || defined(BN_FAST_S_MP_MUL_DIGS_C)
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -10,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* Fast (comba) multiplier
@@ -70,15 +66,15 @@ int fast_s_mp_mul_digs(const mp_int *a, const mp_int *b, mp_int *c, int digs)
 
       /* execute loop */
       for (iz = 0; iz < iy; ++iz) {
-         _W += ((mp_word)*tmpx++)*((mp_word)*tmpy--);
+         _W += (mp_word)*tmpx++ * (mp_word)*tmpy--;
 
       }
 
       /* store term */
-      W[ix] = ((mp_digit)_W) & MP_MASK;
+      W[ix] = (mp_digit)_W & MP_MASK;
 
       /* make next carry */
-      _W = _W >> ((mp_word)DIGIT_BIT);
+      _W = _W >> (mp_word)DIGIT_BIT;
    }
 
    /* setup dest */
@@ -88,7 +84,7 @@ int fast_s_mp_mul_digs(const mp_int *a, const mp_int *b, mp_int *c, int digs)
    {
       mp_digit *tmpc;
       tmpc = c->dp;
-      for (ix = 0; ix < (pa + 1); ix++) {
+      for (ix = 0; ix < pa; ix++) {
          /* now extract the previous digit [below the carry] */
          *tmpc++ = W[ix];
       }

bn_fast_s_mp_mul_high_digs.c

@@ -1,6 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-
+#ifdef BN_FAST_S_MP_MUL_HIGH_DIGS_C
-#if defined(ALL_FUNCTIONS) || defined(BN_FAST_S_MP_MUL_HIGH_DIGS_C)
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -10,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* this is a modified version of fast_s_mul_digs that only produces
@@ -61,14 +57,14 @@ int fast_s_mp_mul_high_digs(const mp_int *a, const mp_int *b, mp_int *c, int dig
 
       /* execute loop */
       for (iz = 0; iz < iy; iz++) {
-         _W += ((mp_word)*tmpx++)*((mp_word)*tmpy--);
+         _W += (mp_word)*tmpx++ * (mp_word)*tmpy--;
       }
 
       /* store term */
-      W[ix] = ((mp_digit)_W) & MP_MASK;
+      W[ix] = (mp_digit)_W & MP_MASK;
 
       /* make next carry */
-      _W = _W >> ((mp_word)DIGIT_BIT);
+      _W = _W >> (mp_word)DIGIT_BIT;
    }
 
    /* setup dest */

bn_fast_s_mp_sqr.c

@@ -1,6 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-
+#ifdef BN_FAST_S_MP_SQR_C
-#if defined(ALL_FUNCTIONS) || defined(BN_FAST_S_MP_SQR_C)
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -10,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* the jist of squaring...
@@ -71,22 +67,22 @@ int fast_s_mp_sqr(const mp_int *a, mp_int *b)
 
       /* execute loop */
       for (iz = 0; iz < iy; iz++) {
-         _W += ((mp_word)*tmpx++)*((mp_word)*tmpy--);
+         _W += (mp_word)*tmpx++ * (mp_word)*tmpy--;
       }
 
       /* double the inner product and add carry */
       _W = _W + _W + W1;
 
       /* even columns have the square term in them */
-      if ((ix&1) == 0) {
+      if (((unsigned)ix & 1u) == 0u) {
-         _W += ((mp_word)a->dp[ix>>1])*((mp_word)a->dp[ix>>1]);
+         _W += (mp_word)a->dp[ix>>1] * (mp_word)a->dp[ix>>1];
       }
 
       /* store it */
-      W[ix] = (mp_digit)(_W & MP_MASK);
+      W[ix] = _W & MP_MASK;
 
       /* make next carry */
-      W1 = _W >> ((mp_word)DIGIT_BIT);
+      W1 = _W >> (mp_word)DIGIT_BIT;
    }
 
    /* setup dest */

bn_mp_2expt.c

@@ -1,6 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-
+#ifdef BN_MP_2EXPT_C
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_2EXPT_C)
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -10,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* computes a = 2**b
@@ -37,7 +33,7 @@ int mp_2expt(mp_int *a, int b)
    a->used = (b / DIGIT_BIT) + 1;
 
    /* put the single bit in its place */
-   a->dp[b / DIGIT_BIT] = ((mp_digit)1) << (b % DIGIT_BIT);
+   a->dp[b / DIGIT_BIT] = (mp_digit)1 << (mp_digit)(b % DIGIT_BIT);
 
    return MP_OKAY;
 }

bn_mp_abs.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_ABS_C)
+#ifdef BN_MP_ABS_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* b = |a|

bn_mp_add.c

@@ -1,6 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-
+#ifdef BN_MP_ADD_C
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_ADD_C)
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -10,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* high level addition (handles signs) */

bn_mp_add_d.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_ADD_D_C)
+#ifdef BN_MP_ADD_D_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* single digit addition */

bn_mp_addmod.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_ADDMOD_C)
+#ifdef BN_MP_ADDMOD_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* d = a + b (mod c) */

bn_mp_and.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_AND_C)
+#ifdef BN_MP_AND_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* AND two ints together */

bn_mp_clamp.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_CLAMP_C)
+#ifdef BN_MP_CLAMP_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* trim unused digits
@@ -27,7 +24,7 @@ void mp_clamp(mp_int *a)
    /* decrease used while the most significant digit is
     * zero.
     */
-   while ((a->used > 0) && (a->dp[a->used - 1] == 0)) {
+   while ((a->used > 0) && (a->dp[a->used - 1] == 0u)) {
       --(a->used);
    }
 

bn_mp_clear.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_CLEAR_C)
+#ifdef BN_MP_CLEAR_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* clear one (frees)  */

bn_mp_clear_multi.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_CLEAR_MULTI_C)
+#ifdef BN_MP_CLEAR_MULTI_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,11 +9,9 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
+
 #include <stdarg.h>
 
 void mp_clear_multi(mp_int *mp, ...)

bn_mp_cmp.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_CMP_C)
+#ifdef BN_MP_CMP_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* compare two ints (signed)*/

bn_mp_cmp_d.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_CMP_D_C)
+#ifdef BN_MP_CMP_D_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* compare a digit */

bn_mp_cmp_mag.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_CMP_MAG_C)
+#ifdef BN_MP_CMP_MAG_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* compare maginitude of two ints (unsigned) */

bn_mp_cnt_lsb.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_CNT_LSB_C)
+#ifdef BN_MP_CNT_LSB_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 static const int lnz[16] = {
@@ -31,17 +28,17 @@ int mp_cnt_lsb(const mp_int *a)
    }
 
    /* scan lower digits until non-zero */
-   for (x = 0; (x < a->used) && (a->dp[x] == 0); x++) {}
+   for (x = 0; (x < a->used) && (a->dp[x] == 0u); x++) {}
    q = a->dp[x];
    x *= DIGIT_BIT;
 
    /* now scan this digit until a 1 is found */
-   if ((q & 1) == 0) {
+   if ((q & 1u) == 0u) {
       do {
-         qq  = q & 15;
+         qq  = q & 15u;
          x  += lnz[qq];
          q >>= 4;
-      } while (qq == 0);
+      } while (qq == 0u);
    }
    return x;
 }

bn_mp_copy.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_COPY_C)
+#ifdef BN_MP_COPY_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* copy, b = a */

bn_mp_count_bits.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_COUNT_BITS_C)
+#ifdef BN_MP_COUNT_BITS_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* returns the number of bits in an int */
@@ -31,9 +28,9 @@ int mp_count_bits(const mp_int *a)
 
    /* take the last digit and count the bits in it */
    q = a->dp[a->used - 1];
-   while (q > ((mp_digit) 0)) {
+   while (q > (mp_digit)0) {
       ++r;
-      q >>= ((mp_digit) 1);
+      q >>= (mp_digit)1;
    }
    return r;
 }

bn_mp_div.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_DIV_C)
+#ifdef BN_MP_DIV_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 #ifdef BN_MP_DIV_SMALL
@@ -47,7 +44,7 @@ int mp_div(const mp_int *a, const mp_int *b, mp_int *c, mp_int *d)
    }
 
 
-   mp_set(&tq, 1);
+   mp_set(&tq, 1uL);
    n = mp_count_bits(a) - mp_count_bits(b);
    if (((res = mp_abs(a, &ta)) != MP_OKAY) ||
        ((res = mp_abs(b, &tb)) != MP_OKAY) ||
@@ -150,8 +147,8 @@ int mp_div(const mp_int *a, const mp_int *b, mp_int *c, mp_int *d)
 
    /* normalize both x and y, ensure that y >= b/2, [b == 2**DIGIT_BIT] */
    norm = mp_count_bits(&y) % DIGIT_BIT;
-   if (norm < (int)(DIGIT_BIT-1)) {
+   if (norm < (DIGIT_BIT - 1)) {
-      norm = (DIGIT_BIT-1) - norm;
+      norm = (DIGIT_BIT - 1) - norm;
       if ((res = mp_mul_2d(&x, norm, &x)) != MP_OKAY) {
          goto LBL_Y;
       }
@@ -190,16 +187,16 @@ int mp_div(const mp_int *a, const mp_int *b, mp_int *c, mp_int *d)
       /* step 3.1 if xi == yt then set q{i-t-1} to b-1,
        * otherwise set q{i-t-1} to (xi*b + x{i-1})/yt */
       if (x.dp[i] == y.dp[t]) {
-         q.dp[(i - t) - 1] = ((((mp_digit)1) << DIGIT_BIT) - 1);
+         q.dp[(i - t) - 1] = ((mp_digit)1 << (mp_digit)DIGIT_BIT) - (mp_digit)1;
       } else {
          mp_word tmp;
-         tmp = ((mp_word) x.dp[i]) << ((mp_word) DIGIT_BIT);
+         tmp = (mp_word)x.dp[i] << (mp_word)DIGIT_BIT;
-         tmp |= ((mp_word) x.dp[i - 1]);
+         tmp |= (mp_word)x.dp[i - 1];
-         tmp /= ((mp_word) y.dp[t]);
+         tmp /= (mp_word)y.dp[t];
-         if (tmp > (mp_word) MP_MASK) {
+         if (tmp > (mp_word)MP_MASK) {
             tmp = MP_MASK;
          }
-         q.dp[(i - t) - 1] = (mp_digit)(tmp & (mp_word)(MP_MASK));
+         q.dp[(i - t) - 1] = (mp_digit)(tmp & (mp_word)MP_MASK);
       }
 
       /* while (q{i-t-1} * (yt * b + y{t-1})) >
@@ -207,13 +204,13 @@ int mp_div(const mp_int *a, const mp_int *b, mp_int *c, mp_int *d)
 
          do q{i-t-1} -= 1;
       */
-      q.dp[(i - t) - 1] = (q.dp[(i - t) - 1] + 1) & MP_MASK;
+      q.dp[(i - t) - 1] = (q.dp[(i - t) - 1] + 1uL) & (mp_digit)MP_MASK;
       do {
-         q.dp[(i - t) - 1] = (q.dp[(i - t) - 1] - 1) & MP_MASK;
+         q.dp[(i - t) - 1] = (q.dp[(i - t) - 1] - 1uL) & (mp_digit)MP_MASK;
 
          /* find left hand */
          mp_zero(&t1);
-         t1.dp[0] = ((t - 1) < 0) ? 0 : y.dp[t - 1];
+         t1.dp[0] = ((t - 1) < 0) ? 0u : y.dp[t - 1];
          t1.dp[1] = y.dp[t];
          t1.used = 2;
          if ((res = mp_mul_d(&t1, q.dp[(i - t) - 1], &t1)) != MP_OKAY) {
@@ -221,8 +218,8 @@ int mp_div(const mp_int *a, const mp_int *b, mp_int *c, mp_int *d)
          }
 
          /* find right hand */
-         t2.dp[0] = ((i - 2) < 0) ? 0 : x.dp[i - 2];
+         t2.dp[0] = ((i - 2) < 0) ? 0u : x.dp[i - 2];
-         t2.dp[1] = ((i - 1) < 0) ? 0 : x.dp[i - 1];
+         t2.dp[1] = ((i - 1) < 0) ? 0u : x.dp[i - 1];
          t2.dp[2] = x.dp[i];
          t2.used = 3;
       } while (mp_cmp_mag(&t1, &t2) == MP_GT);
@@ -252,7 +249,7 @@ int mp_div(const mp_int *a, const mp_int *b, mp_int *c, mp_int *d)
             goto LBL_Y;
          }
 
-         q.dp[(i - t) - 1] = (q.dp[(i - t) - 1] - 1UL) & MP_MASK;
+         q.dp[(i - t) - 1] = (q.dp[(i - t) - 1] - 1uL) & MP_MASK;
       }
    }
 

bn_mp_div_2.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_DIV_2_C)
+#ifdef BN_MP_DIV_2_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* b = a/2 */
@@ -42,7 +39,7 @@ int mp_div_2(const mp_int *a, mp_int *b)
       r = 0;
       for (x = b->used - 1; x >= 0; x--) {
          /* get the carry for the next iteration */
-         rr = *tmpa & 1;
+         rr = *tmpa & 1u;
 
          /* shift the current digit, add in carry and store */
          *tmpb-- = (*tmpa-- >> 1) | (r << (DIGIT_BIT - 1));

bn_mp_div_2d.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_DIV_2D_C)
+#ifdef BN_MP_DIV_2D_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* shift right by a certain bit count (store quotient in c, optional remainder in d) */
@@ -44,20 +41,20 @@ int mp_div_2d(const mp_int *a, int b, mp_int *c, mp_int *d)
    }
 
    /* shift by as many digits in the bit count */
-   if (b >= (int)DIGIT_BIT) {
+   if (b >= DIGIT_BIT) {
       mp_rshd(c, b / DIGIT_BIT);
    }
 
    /* shift any bit count < DIGIT_BIT */
    D = (mp_digit)(b % DIGIT_BIT);
-   if (D != 0) {
+   if (D != 0u) {
       mp_digit *tmpc, mask, shift;
 
       /* mask */
-      mask = (((mp_digit)1) << D) - 1;
+      mask = ((mp_digit)1 << D) - 1uL;
 
       /* shift for lsb */
-      shift = DIGIT_BIT - D;
+      shift = (mp_digit)DIGIT_BIT - D;
 
       /* alias */
       tmpc = c->dp + (c->used - 1);

bn_mp_div_3.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_DIV_3_C)
+#ifdef BN_MP_DIV_3_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* divide by three (based on routine from MPI and the GMP manual) */
@@ -24,7 +21,7 @@ int mp_div_3(const mp_int *a, mp_int *c, mp_digit *d)
    int      res, ix;
 
    /* b = 2**DIGIT_BIT / 3 */
-   b = (((mp_word)1) << ((mp_word)DIGIT_BIT)) / ((mp_word)3);
+   b = ((mp_word)1 << (mp_word)DIGIT_BIT) / (mp_word)3;
 
    if ((res = mp_init_size(&q, a->used)) != MP_OKAY) {
       return res;
@@ -34,11 +31,11 @@ int mp_div_3(const mp_int *a, mp_int *c, mp_digit *d)
    q.sign = a->sign;
    w = 0;
    for (ix = a->used - 1; ix >= 0; ix--) {
-      w = (w << ((mp_word)DIGIT_BIT)) | ((mp_word)a->dp[ix]);
+      w = (w << (mp_word)DIGIT_BIT) | (mp_word)a->dp[ix];
 
-      if (w >= 3) {
+      if (w >= 3u) {
          /* multiply w by [1/3] */
-         t = (w * ((mp_word)b)) >> ((mp_word)DIGIT_BIT);
+         t = (w * (mp_word)b) >> (mp_word)DIGIT_BIT;
 
          /* now subtract 3 * [w/3] from w, to get the remainder */
          w -= t+t+t;
@@ -46,9 +43,9 @@ int mp_div_3(const mp_int *a, mp_int *c, mp_digit *d)
          /* fixup the remainder as required since
           * the optimization is not exact.
           */
-         while (w >= 3) {
+         while (w >= 3u) {
-            t += 1;
+            t += 1u;
-            w -= 3;
+            w -= 3u;
          }
       } else {
          t = 0;

bn_mp_div_d.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_DIV_D_C)
+#ifdef BN_MP_DIV_D_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 static int s_is_power_of_two(mp_digit b, int *p)
@@ -20,12 +17,12 @@ static int s_is_power_of_two(mp_digit b, int *p)
    int x;
 
    /* fast return if no power of two */
-   if ((b == 0) || ((b & (b-1)) != 0)) {
+   if ((b == 0u) || ((b & (b-1u)) != 0u)) {
       return 0;
    }
 
    for (x = 0; x < DIGIT_BIT; x++) {
-      if (b == (((mp_digit)1)<<x)) {
+      if (b == ((mp_digit)1<<(mp_digit)x)) {
          *p = x;
          return 1;
       }
@@ -42,12 +39,12 @@ int mp_div_d(const mp_int *a, mp_digit b, mp_int *c, mp_digit *d)
    int     res, ix;
 
    /* cannot divide by zero */
-   if (b == 0) {
+   if (b == 0u) {
       return MP_VAL;
    }
 
    /* quick outs */
-   if ((b == 1) || (mp_iszero(a) == MP_YES)) {
+   if ((b == 1u) || (mp_iszero(a) == MP_YES)) {
       if (d != NULL) {
          *d = 0;
       }
@@ -60,7 +57,7 @@ int mp_div_d(const mp_int *a, mp_digit b, mp_int *c, mp_digit *d)
    /* power of two ? */
    if (s_is_power_of_two(b, &ix) == 1) {
       if (d != NULL) {
-         *d = a->dp[0] & ((((mp_digit)1)<<ix) - 1);
+         *d = a->dp[0] & (((mp_digit)1<<(mp_digit)ix) - 1uL);
       }
       if (c != NULL) {
          return mp_div_2d(a, ix, c, NULL);
@@ -70,7 +67,7 @@ int mp_div_d(const mp_int *a, mp_digit b, mp_int *c, mp_digit *d)
 
 #ifdef BN_MP_DIV_3_C
    /* three? */
-   if (b == 3) {
+   if (b == 3u) {
       return mp_div_3(a, c, d);
    }
 #endif
@@ -84,15 +81,15 @@ int mp_div_d(const mp_int *a, mp_digit b, mp_int *c, mp_digit *d)
    q.sign = a->sign;
    w = 0;
    for (ix = a->used - 1; ix >= 0; ix--) {
-      w = (w << ((mp_word)DIGIT_BIT)) | ((mp_word)a->dp[ix]);
+      w = (w << (mp_word)DIGIT_BIT) | (mp_word)a->dp[ix];
 
       if (w >= b) {
          t = (mp_digit)(w / b);
-         w -= ((mp_word)t) * ((mp_word)b);
+         w -= (mp_word)t * (mp_word)b;
       } else {
          t = 0;
       }
-      q.dp[ix] = (mp_digit)t;
+      q.dp[ix] = t;
    }
 
    if (d != NULL) {

bn_mp_dr_is_modulus.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_DR_IS_MODULUS_C)
+#ifdef BN_MP_DR_IS_MODULUS_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* determines if a number is a valid DR modulus */

bn_mp_dr_reduce.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_DR_REDUCE_C)
+#ifdef BN_MP_DR_REDUCE_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* reduce "x" in place modulo "n" using the Diminished Radix algorithm.
@@ -61,7 +58,7 @@ top:
 
    /* compute (x mod B**m) + k * [x/B**m] inline and inplace */
    for (i = 0; i < m; i++) {
-      r         = (((mp_word)*tmpx2++) * (mp_word)k) + *tmpx1 + mu;
+      r         = ((mp_word)*tmpx2++ * (mp_word)k) + *tmpx1 + mu;
       *tmpx1++  = (mp_digit)(r & MP_MASK);
       mu        = (mp_digit)(r >> ((mp_word)DIGIT_BIT));
    }

bn_mp_dr_setup.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_DR_SETUP_C)
+#ifdef BN_MP_DR_SETUP_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* determines the setup value */
@@ -21,7 +18,7 @@ void mp_dr_setup(const mp_int *a, mp_digit *d)
    /* the casts are required if DIGIT_BIT is one less than
     * the number of bits in a mp_digit [e.g. DIGIT_BIT==31]
     */
-   *d = (mp_digit)((((mp_word)1) << ((mp_word)DIGIT_BIT)) - ((mp_word)a->dp[0]));
+   *d = (mp_digit)(((mp_word)1 << (mp_word)DIGIT_BIT) - (mp_word)a->dp[0]);
 }
 
 #endif

bn_mp_exch.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_EXCH_C)
+#ifdef BN_MP_EXCH_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* swap the elements of two integers, for cases where you can't simply swap the

bn_mp_export.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_EXPORT_C)
+#ifdef BN_MP_EXPORT_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* based on gmp's mpz_export.
@@ -38,33 +35,33 @@ int mp_export(void *rop, size_t *countp, int order, size_t size,
       } lint;
       lint.i = 0x01020304;
 
-      endian = (lint.c[0] == 4) ? -1 : 1;
+      endian = (lint.c[0] == '\x04') ? -1 : 1;
    }
 
-   odd_nails = (nails % 8);
+   odd_nails = (nails % 8u);
    odd_nail_mask = 0xff;
    for (i = 0; i < odd_nails; ++i) {
-      odd_nail_mask ^= (1 << (7 - i));
+      odd_nail_mask ^= (unsigned char)(1u << (7u - i));
    }
-   nail_bytes = nails / 8;
+   nail_bytes = nails / 8u;
 
-   bits = mp_count_bits(&t);
+   bits = (size_t)mp_count_bits(&t);
-   count = (bits / ((size * 8) - nails)) + (((bits % ((size * 8) - nails)) != 0) ? 1 : 0);
+   count = (bits / ((size * 8u) - nails)) + (((bits % ((size * 8u) - nails)) != 0u) ? 1u : 0u);
 
    for (i = 0; i < count; ++i) {
       for (j = 0; j < size; ++j) {
          unsigned char *byte = (unsigned char *)rop +
-                               (((order == -1) ? i : ((count - 1) - i)) * size) +
+                               (((order == -1) ? i : ((count - 1u) - i)) * size) +
-                               ((endian == -1) ? j : ((size - 1) - j));
+                               ((endian == -1) ? j : ((size - 1u) - j));
 
          if (j >= (size - nail_bytes)) {
             *byte = 0;
             continue;
          }
 
-         *byte = (unsigned char)((j == ((size - nail_bytes) - 1)) ? (t.dp[0] & odd_nail_mask) : (t.dp[0] & 0xFF));
+         *byte = (unsigned char)((j == ((size - nail_bytes) - 1u)) ? (t.dp[0] & odd_nail_mask) : (t.dp[0] & 0xFFuL));
 
-         if ((result = mp_div_2d(&t, ((j == ((size - nail_bytes) - 1)) ? (8 - odd_nails) : 8), &t, NULL)) != MP_OKAY) {
+         if ((result = mp_div_2d(&t, (j == ((size - nail_bytes) - 1u)) ? (int)(8u - odd_nails) : 8, &t, NULL)) != MP_OKAY) {
             mp_clear(&t);
             return result;
          }

bn_mp_expt_d.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_EXPT_D_C)
+#ifdef BN_MP_EXPT_D_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* wrapper function for mp_expt_d_ex() */

bn_mp_expt_d_ex.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_EXPT_D_EX_C)
+#ifdef BN_MP_EXPT_D_EX_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* calculate c = a**b  using a square-multiply algorithm */
@@ -28,12 +25,12 @@ int mp_expt_d_ex(const mp_int *a, mp_digit b, mp_int *c, int fast)
    }
 
    /* set initial result */
-   mp_set(c, 1);
+   mp_set(c, 1uL);
 
    if (fast != 0) {
-      while (b > 0) {
+      while (b > 0u) {
          /* if the bit is set multiply */
-         if ((b & 1) != 0) {
+         if ((b & 1u) != 0u) {
             if ((res = mp_mul(c, &g, c)) != MP_OKAY) {
                mp_clear(&g);
                return res;
@@ -41,7 +38,7 @@ int mp_expt_d_ex(const mp_int *a, mp_digit b, mp_int *c, int fast)
          }
 
          /* square */
-         if (b > 1) {
+         if (b > 1u) {
             if ((res = mp_sqr(&g, &g)) != MP_OKAY) {
                mp_clear(&g);
                return res;
@@ -52,7 +49,7 @@ int mp_expt_d_ex(const mp_int *a, mp_digit b, mp_int *c, int fast)
          b >>= 1;
       }
    } else {
-      for (x = 0; x < DIGIT_BIT; x++) {
+      for (x = 0; x < (unsigned)DIGIT_BIT; x++) {
          /* square */
          if ((res = mp_sqr(c, c)) != MP_OKAY) {
             mp_clear(&g);
@@ -60,7 +57,7 @@ int mp_expt_d_ex(const mp_int *a, mp_digit b, mp_int *c, int fast)
          }
 
          /* if the bit is set multiply */
-         if ((b & (mp_digit)(((mp_digit)1) << (DIGIT_BIT - 1))) != 0) {
+         if ((b & ((mp_digit)1 << (DIGIT_BIT - 1))) != 0u) {
             if ((res = mp_mul(c, &g, c)) != MP_OKAY) {
                mp_clear(&g);
                return res;

bn_mp_exptmod.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_EXPTMOD_C)
+#ifdef BN_MP_EXPTMOD_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 
@@ -21,15 +18,6 @@
  * embedded in the normal function but that wasted alot of stack space
  * for nothing (since 99% of the time the Montgomery code would be called)
  */
-
-#define BN_MP_REDUCE_IS_2K_L_C
-#define BN_MP_REDUCE_2K_L_C
-#define BN_S_MP_EXPTMOD_C
-#define BN_MP_DR_IS_MODULUS_C
-#define BN_MP_REDUCE_IS_2K_C
-#define BN_MP_EXPTMOD_FAST_C
-#define BN_MP_INVMOD_C
-
 int mp_exptmod(const mp_int *G, const mp_int *X, const mp_int *P, mp_int *Y)
 {
    int dr;

bn_mp_exptmod_fast.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_EXPTMOD_FAST_C)
+#ifdef BN_MP_EXPTMOD_FAST_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* computes Y == G**X mod P, HAC pp.616, Algorithm 14.85
@@ -29,14 +26,6 @@
 #   define TAB_SIZE 256
 #endif
 
-#define BN_MP_MONTGOMERY_SETUP_C
-#define BN_FAST_MP_MONTGOMERY_REDUCE_C
-#define BN_MP_MONTGOMERY_REDUCE_C
-#define BN_MP_DR_SETUP_C
-#define BN_MP_DR_REDUCE_C
-#define BN_MP_REDUCE_2K_SETUP_C
-#define BN_MP_REDUCE_2K_C
-#define BN_MP_MONTGOMERY_CALC_NORMALIZATION_C
 int mp_exptmod_fast(const mp_int *G, const mp_int *X, const mp_int *P, mp_int *Y, int redmode)
 {
    mp_int  M[TAB_SIZE], res;
@@ -47,7 +36,7 @@ int mp_exptmod_fast(const mp_int *G, const mp_int *X, const mp_int *P, mp_int *Y
     * one of many reduction algorithms without modding the guts of
     * the code with if statements everywhere.
     */
-   int (*redux)(mp_int *,const mp_int *,mp_digit);
+   int (*redux)(mp_int *x, const mp_int *n, mp_digit rho);
 
    /* find window size */
    x = mp_count_bits(X);
@@ -104,7 +93,7 @@ int mp_exptmod_fast(const mp_int *G, const mp_int *X, const mp_int *P, mp_int *Y
 
       /* automatically pick the comba one if available (saves quite a few calls/ifs) */
 #ifdef BN_FAST_MP_MONTGOMERY_REDUCE_C
-      if ((((P->used * 2) + 1) < MP_WARRAY) &&
+      if ((((P->used * 2) + 1) < (int)MP_WARRAY) &&
           (P->used < (1 << ((CHAR_BIT * sizeof(mp_word)) - (2 * DIGIT_BIT))))) {
          redux = fast_mp_montgomery_reduce;
       } else
@@ -168,22 +157,22 @@ int mp_exptmod_fast(const mp_int *G, const mp_int *X, const mp_int *P, mp_int *Y
       goto LBL_RES;
 #endif
    } else {
-      mp_set(&res, 1);
+      mp_set(&res, 1uL);
       if ((err = mp_mod(G, P, &M[1])) != MP_OKAY) {
          goto LBL_RES;
       }
    }
 
    /* compute the value at M[1<<(winsize-1)] by squaring M[1] (winsize-1) times */
-   if ((err = mp_copy(&M[1], &M[1 << (winsize - 1)])) != MP_OKAY) {
+   if ((err = mp_copy(&M[1], &M[(size_t)1 << (winsize - 1)])) != MP_OKAY) {
       goto LBL_RES;
    }
 
    for (x = 0; x < (winsize - 1); x++) {
-      if ((err = mp_sqr(&M[1 << (winsize - 1)], &M[1 << (winsize - 1)])) != MP_OKAY) {
+      if ((err = mp_sqr(&M[(size_t)1 << (winsize - 1)], &M[(size_t)1 << (winsize - 1)])) != MP_OKAY) {
          goto LBL_RES;
       }
-      if ((err = redux(&M[1 << (winsize - 1)], P, mp)) != MP_OKAY) {
+      if ((err = redux(&M[(size_t)1 << (winsize - 1)], P, mp)) != MP_OKAY) {
          goto LBL_RES;
       }
    }

bn_mp_exteuclid.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_EXTEUCLID_C)
+#ifdef BN_MP_EXTEUCLID_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* Extended euclidean algorithm of (a, b) produces
@@ -28,76 +25,76 @@ int mp_exteuclid(const mp_int *a, const mp_int *b, mp_int *U1, mp_int *U2, mp_in
    }
 
    /* initialize, (u1,u2,u3) = (1,0,a) */
-   mp_set(&u1, 1);
+   mp_set(&u1, 1uL);
-   if ((err = mp_copy(a, &u3)) != MP_OKAY)                                        {
+   if ((err = mp_copy(a, &u3)) != MP_OKAY) {
       goto LBL_ERR;
    }
 
    /* initialize, (v1,v2,v3) = (0,1,b) */
-   mp_set(&v2, 1);
+   mp_set(&v2, 1uL);
-   if ((err = mp_copy(b, &v3)) != MP_OKAY)                                        {
+   if ((err = mp_copy(b, &v3)) != MP_OKAY) {
       goto LBL_ERR;
    }
 
    /* loop while v3 != 0 */
    while (mp_iszero(&v3) == MP_NO) {
       /* q = u3/v3 */
-      if ((err = mp_div(&u3, &v3, &q, NULL)) != MP_OKAY)                         {
+      if ((err = mp_div(&u3, &v3, &q, NULL)) != MP_OKAY) {
          goto LBL_ERR;
       }
 
       /* (t1,t2,t3) = (u1,u2,u3) - (v1,v2,v3)q */
-      if ((err = mp_mul(&v1, &q, &tmp)) != MP_OKAY)                              {
+      if ((err = mp_mul(&v1, &q, &tmp)) != MP_OKAY) {
          goto LBL_ERR;
       }
-      if ((err = mp_sub(&u1, &tmp, &t1)) != MP_OKAY)                             {
+      if ((err = mp_sub(&u1, &tmp, &t1)) != MP_OKAY) {
          goto LBL_ERR;
       }
-      if ((err = mp_mul(&v2, &q, &tmp)) != MP_OKAY)                              {
+      if ((err = mp_mul(&v2, &q, &tmp)) != MP_OKAY) {
          goto LBL_ERR;
       }
-      if ((err = mp_sub(&u2, &tmp, &t2)) != MP_OKAY)                             {
+      if ((err = mp_sub(&u2, &tmp, &t2)) != MP_OKAY) {
          goto LBL_ERR;
       }
-      if ((err = mp_mul(&v3, &q, &tmp)) != MP_OKAY)                              {
+      if ((err = mp_mul(&v3, &q, &tmp)) != MP_OKAY) {
          goto LBL_ERR;
       }
-      if ((err = mp_sub(&u3, &tmp, &t3)) != MP_OKAY)                             {
+      if ((err = mp_sub(&u3, &tmp, &t3)) != MP_OKAY) {
          goto LBL_ERR;
       }
 
       /* (u1,u2,u3) = (v1,v2,v3) */
-      if ((err = mp_copy(&v1, &u1)) != MP_OKAY)                                  {
+      if ((err = mp_copy(&v1, &u1)) != MP_OKAY) {
          goto LBL_ERR;
       }
-      if ((err = mp_copy(&v2, &u2)) != MP_OKAY)                                  {
+      if ((err = mp_copy(&v2, &u2)) != MP_OKAY) {
          goto LBL_ERR;
       }
-      if ((err = mp_copy(&v3, &u3)) != MP_OKAY)                                  {
+      if ((err = mp_copy(&v3, &u3)) != MP_OKAY) {
          goto LBL_ERR;
       }
 
       /* (v1,v2,v3) = (t1,t2,t3) */
-      if ((err = mp_copy(&t1, &v1)) != MP_OKAY)                                  {
+      if ((err = mp_copy(&t1, &v1)) != MP_OKAY) {
          goto LBL_ERR;
       }
-      if ((err = mp_copy(&t2, &v2)) != MP_OKAY)                                  {
+      if ((err = mp_copy(&t2, &v2)) != MP_OKAY) {
          goto LBL_ERR;
       }
-      if ((err = mp_copy(&t3, &v3)) != MP_OKAY)                                  {
+      if ((err = mp_copy(&t3, &v3)) != MP_OKAY) {
          goto LBL_ERR;
       }
    }
 
    /* make sure U3 >= 0 */
    if (u3.sign == MP_NEG) {
-      if ((err = mp_neg(&u1, &u1)) != MP_OKAY)                                   {
+      if ((err = mp_neg(&u1, &u1)) != MP_OKAY) {
          goto LBL_ERR;
       }
-      if ((err = mp_neg(&u2, &u2)) != MP_OKAY)                                   {
+      if ((err = mp_neg(&u2, &u2)) != MP_OKAY) {
          goto LBL_ERR;
       }
-      if ((err = mp_neg(&u3, &u3)) != MP_OKAY)                                   {
+      if ((err = mp_neg(&u3, &u3)) != MP_OKAY) {
          goto LBL_ERR;
       }
    }

bn_mp_fread.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_FREAD_C)
+#ifdef BN_MP_FREAD_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 #ifndef LTM_NO_FILE
@@ -20,13 +17,14 @@
 int mp_fread(mp_int *a, int radix, FILE *stream)
 {
    int err, ch, neg, y;
+   unsigned pos;
 
    /* clear a */
    mp_zero(a);
 
    /* if first digit is - then set negative */
    ch = fgetc(stream);
-   if (ch == '-') {
+   if (ch == (int)'-') {
       neg = MP_NEG;
       ch = fgetc(stream);
    } else {
@@ -34,27 +32,28 @@ int mp_fread(mp_int *a, int radix, FILE *stream)
    }
 
    for (;;) {
-      /* find y in the radix map */
+      pos = (unsigned)(ch - (int)'(');
-      for (y = 0; y < radix; y++) {
+      if (mp_s_rmap_reverse_sz < pos) {
-         if (mp_s_rmap[y] == ch) {
+         break;
-            break;
-         }
       }
-      if (y == radix) {
+
+      y = (int)mp_s_rmap_reverse[pos];
+
+      if ((y == 0xff) || (y >= radix)) {
          break;
       }
 
       /* shift up and add */
-      if ((err = mp_mul_d(a, radix, a)) != MP_OKAY) {
+      if ((err = mp_mul_d(a, (mp_digit)radix, a)) != MP_OKAY) {
          return err;
       }
-      if ((err = mp_add_d(a, y, a)) != MP_OKAY) {
+      if ((err = mp_add_d(a, (mp_digit)y, a)) != MP_OKAY) {
          return err;
       }
 
       ch = fgetc(stream);
    }
-   if (mp_cmp_d(a, 0) != MP_EQ) {
+   if (mp_cmp_d(a, 0uL) != MP_EQ) {
       a->sign = neg;
    }
 

bn_mp_fwrite.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_FWRITE_C)
+#ifdef BN_MP_FWRITE_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 #ifndef LTM_NO_FILE
@@ -25,7 +22,7 @@ int mp_fwrite(const mp_int *a, int radix, FILE *stream)
       return err;
    }
 
-   buf = OPT_CAST(char) XMALLOC(len);
+   buf = OPT_CAST(char) XMALLOC((size_t)len);
    if (buf == NULL) {
       return MP_MEM;
    }
@@ -36,7 +33,7 @@ int mp_fwrite(const mp_int *a, int radix, FILE *stream)
    }
 
    for (x = 0; x < len; x++) {
-      if (fputc(buf[x], stream) == EOF) {
+      if (fputc((int)buf[x], stream) == EOF) {
          XFREE(buf);
          return MP_VAL;
       }

bn_mp_gcd.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_GCD_C)
+#ifdef BN_MP_GCD_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* Greatest Common Divisor using the binary method */

bn_mp_get_int.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_GET_INT_C)
+#ifdef BN_MP_GET_INT_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* get the lower 32-bits of an mp_int */
@@ -26,7 +23,7 @@ unsigned long mp_get_int(const mp_int *a)
    }
 
    /* get number of digits of the lsb we have to read */
-   i = MIN(a->used, (int)(((sizeof(unsigned long) * CHAR_BIT) + DIGIT_BIT - 1) / DIGIT_BIT)) - 1;
+   i = MIN(a->used, ((((int)sizeof(unsigned long) * CHAR_BIT) + DIGIT_BIT - 1) / DIGIT_BIT)) - 1;
 
    /* get most significant digit of result */
    res = DIGIT(a, i);

bn_mp_get_long.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_GET_LONG_C)
+#ifdef BN_MP_GET_LONG_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* get the lower unsigned long of an mp_int, platform dependent */
@@ -26,7 +23,7 @@ unsigned long mp_get_long(const mp_int *a)
    }
 
    /* get number of digits of the lsb we have to read */
-   i = MIN(a->used, (int)(((sizeof(unsigned long) * CHAR_BIT) + DIGIT_BIT - 1) / DIGIT_BIT)) - 1;
+   i = MIN(a->used, ((((int)sizeof(unsigned long) * CHAR_BIT) + DIGIT_BIT - 1) / DIGIT_BIT)) - 1;
 
    /* get most significant digit of result */
    res = DIGIT(a, i);
@@ -39,3 +36,7 @@ unsigned long mp_get_long(const mp_int *a)
    return res;
 }
 #endif
+
+/* ref:         $Format:%D$ */
+/* git commit:  $Format:%H$ */
+/* commit time: $Format:%ai$ */

bn_mp_get_long_long.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_GET_LONG_LONG_C)
+#ifdef BN_MP_GET_LONG_LONG_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* get the lower unsigned long long of an mp_int, platform dependent */
@@ -26,7 +23,7 @@ unsigned long long mp_get_long_long(const mp_int *a)
    }
 
    /* get number of digits of the lsb we have to read */
-   i = MIN(a->used, (int)(((sizeof(unsigned long long) * CHAR_BIT) + DIGIT_BIT - 1) / DIGIT_BIT)) - 1;
+   i = MIN(a->used, ((((int)sizeof(unsigned long long) * CHAR_BIT) + DIGIT_BIT - 1) / DIGIT_BIT)) - 1;
 
    /* get most significant digit of result */
    res = DIGIT(a, i);
@@ -39,3 +36,7 @@ unsigned long long mp_get_long_long(const mp_int *a)
    return res;
 }
 #endif
+
+/* ref:         $Format:%D$ */
+/* git commit:  $Format:%H$ */
+/* commit time: $Format:%ai$ */

bn_mp_grow.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_GROW_C)
+#ifdef BN_MP_GROW_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* grow as required */
@@ -32,7 +29,7 @@ int mp_grow(mp_int *a, int size)
        * in case the operation failed we don't want
        * to overwrite the dp member of a.
        */
-      tmp = OPT_CAST(mp_digit) XREALLOC(a->dp, sizeof(mp_digit) * size);
+      tmp = OPT_CAST(mp_digit) XREALLOC(a->dp, sizeof(mp_digit) * (size_t)size);
       if (tmp == NULL) {
          /* reallocation failed but "a" is still valid [can be freed] */
          return MP_MEM;

bn_mp_import.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_IMPORT_C)
+#ifdef BN_MP_IMPORT_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* based on gmp's mpz_import.
@@ -34,27 +31,27 @@ int mp_import(mp_int *rop, size_t count, int order, size_t size,
       } lint;
       lint.i = 0x01020304;
 
-      endian = (lint.c[0] == 4) ? -1 : 1;
+      endian = (lint.c[0] == '\x04') ? -1 : 1;
    }
 
-   odd_nails = (nails % 8);
+   odd_nails = (nails % 8u);
    odd_nail_mask = 0xff;
    for (i = 0; i < odd_nails; ++i) {
-      odd_nail_mask ^= (1 << (7 - i));
+      odd_nail_mask ^= (unsigned char)(1u << (7u - i));
    }
-   nail_bytes = nails / 8;
+   nail_bytes = nails / 8u;
 
    for (i = 0; i < count; ++i) {
       for (j = 0; j < (size - nail_bytes); ++j) {
          unsigned char byte = *((unsigned char *)op +
-                                (((order == 1) ? i : ((count - 1) - i)) * size) +
+                                (((order == 1) ? i : ((count - 1u) - i)) * size) +
-                                ((endian == 1) ? (j + nail_bytes) : (((size - 1) - j) - nail_bytes)));
+                                ((endian == 1) ? (j + nail_bytes) : (((size - 1u) - j) - nail_bytes)));
 
-         if ((result = mp_mul_2d(rop, ((j == 0) ? (8 - odd_nails) : 8), rop)) != MP_OKAY) {
+         if ((result = mp_mul_2d(rop, (j == 0u) ? (int)(8u - odd_nails) : 8, rop)) != MP_OKAY) {
             return result;
          }
 
-         rop->dp[0] |= (j == 0) ? (byte & odd_nail_mask) : byte;
+         rop->dp[0] |= (j == 0u) ? (mp_digit)(byte & odd_nail_mask) : (mp_digit)byte;
          rop->used  += 1;
       }
    }

bn_mp_init.c

@@ -1,6 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-
+#ifdef BN_MP_INIT_C
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_INIT_C)
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -10,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* init a new mp_int */
@@ -22,7 +18,7 @@ int mp_init(mp_int *a)
    int i;
 
    /* allocate memory required and clear it */
-   a->dp = OPT_CAST(mp_digit) XMALLOC(sizeof(mp_digit) * MP_PREC);
+   a->dp = OPT_CAST(mp_digit) XMALLOC(sizeof(mp_digit) * (size_t)MP_PREC);
    if (a->dp == NULL) {
       return MP_MEM;
    }

bn_mp_init_copy.c

@@ -1,6 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-
+#ifdef BN_MP_INIT_COPY_C
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_INIT_COPY_C)
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -10,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* creates "a" then copies b into it */

bn_mp_init_multi.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_INIT_MULTI_C)
+#ifdef BN_MP_INIT_MULTI_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,11 +9,9 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
+
 #include <stdarg.h>
 
 int mp_init_multi(mp_int *mp, ...)

bn_mp_init_set.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_INIT_SET_C)
+#ifdef BN_MP_INIT_SET_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* initialize and set a digit */

bn_mp_init_set_int.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_INIT_SET_INT_C)
+#ifdef BN_MP_INIT_SET_INT_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* initialize and set a digit */

bn_mp_init_size.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_INIT_SIZE_C)
+#ifdef BN_MP_INIT_SIZE_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* init an mp_init for a given size */
@@ -24,7 +21,7 @@ int mp_init_size(mp_int *a, int size)
    size += (MP_PREC * 2) - (size % MP_PREC);
 
    /* alloc mem */
-   a->dp = OPT_CAST(mp_digit) XMALLOC(sizeof(mp_digit) * size);
+   a->dp = OPT_CAST(mp_digit) XMALLOC(sizeof(mp_digit) * (size_t)size);
    if (a->dp == NULL) {
       return MP_MEM;
    }

bn_mp_invmod.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_INVMOD_C)
+#ifdef BN_MP_INVMOD_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,26 +9,20 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* hac 14.61, pp608 */
-
-#define BN_FAST_MP_INVMOD_C
-#define BN_MP_INVMOD_SLOW_C
 int mp_invmod(const mp_int *a, const mp_int *b, mp_int *c)
 {
-   /* b cannot be negative */
+   /* b cannot be negative and has to be >1 */
-   if ((b->sign == MP_NEG) || (mp_iszero(b) == MP_YES)) {
+   if ((b->sign == MP_NEG) || (mp_cmp_d(b, 1uL) != MP_GT)) {
       return MP_VAL;
    }
 
 #ifdef BN_FAST_MP_INVMOD_C
    /* if the modulus is odd we can use a faster routine instead */
-   if ((mp_isodd(b) == MP_YES) && (mp_cmp_d(b, 1) != MP_EQ)) {
+   if ((mp_isodd(b) == MP_YES)) {
       return fast_mp_invmod(a, b, c);
    }
 #endif

bn_mp_invmod_slow.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_INVMOD_SLOW_C)
+#ifdef BN_MP_INVMOD_SLOW_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* hac 14.61, pp608 */
@@ -53,8 +50,8 @@ int mp_invmod_slow(const mp_int *a, const mp_int *b, mp_int *c)
    if ((res = mp_copy(&y, &v)) != MP_OKAY) {
       goto LBL_ERR;
    }
-   mp_set(&A, 1);
+   mp_set(&A, 1uL);
-   mp_set(&D, 1);
+   mp_set(&D, 1uL);
 
 top:
    /* 4.  while u is even do */
@@ -143,13 +140,13 @@ top:
    /* now a = C, b = D, gcd == g*v */
 
    /* if v != 1 then there is no inverse */
-   if (mp_cmp_d(&v, 1) != MP_EQ) {
+   if (mp_cmp_d(&v, 1uL) != MP_EQ) {
       res = MP_VAL;
       goto LBL_ERR;
    }
 
    /* if its too low */
-   while (mp_cmp_d(&C, 0) == MP_LT) {
+   while (mp_cmp_d(&C, 0uL) == MP_LT) {
       if ((res = mp_add(&C, b, &C)) != MP_OKAY) {
          goto LBL_ERR;
       }

bn_mp_is_square.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_IS_SQUARE_C)
+#ifdef BN_MP_IS_SQUARE_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* Check if remainders are possible squares - fast exclude non-squares */
@@ -58,15 +55,15 @@ int mp_is_square(const mp_int *arg, int *ret)
    }
 
    /* First check mod 128 (suppose that DIGIT_BIT is at least 7) */
-   if (rem_128[127 & DIGIT(arg, 0)] == 1) {
+   if (rem_128[127u & DIGIT(arg, 0)] == (char)1) {
       return MP_OKAY;
    }
 
    /* Next check mod 105 (3*5*7) */
-   if ((res = mp_mod_d(arg, 105, &c)) != MP_OKAY) {
+   if ((res = mp_mod_d(arg, 105uL, &c)) != MP_OKAY) {
       return res;
    }
-   if (rem_105[c] == 1) {
+   if (rem_105[c] == (char)1) {
       return MP_OKAY;
    }
 
@@ -75,31 +72,31 @@ int mp_is_square(const mp_int *arg, int *ret)
       return res;
    }
    if ((res = mp_mod(arg, &t, &t)) != MP_OKAY) {
-      goto ERR;
+      goto LBL_ERR;
    }
    r = mp_get_int(&t);
    /* Check for other prime modules, note it's not an ERROR but we must
-    * free "t" so the easiest way is to goto ERR.  We know that res
+    * free "t" so the easiest way is to goto LBL_ERR.  We know that res
     * is already equal to MP_OKAY from the mp_mod call
     */
-   if (((1L<<(r%11)) & 0x5C4L) != 0L)       goto ERR;
+   if (((1uL<<(r%11uL)) & 0x5C4uL) != 0uL)         goto LBL_ERR;
-   if (((1L<<(r%13)) & 0x9E4L) != 0L)       goto ERR;
+   if (((1uL<<(r%13uL)) & 0x9E4uL) != 0uL)         goto LBL_ERR;
-   if (((1L<<(r%17)) & 0x5CE8L) != 0L)      goto ERR;
+   if (((1uL<<(r%17uL)) & 0x5CE8uL) != 0uL)        goto LBL_ERR;
-   if (((1L<<(r%19)) & 0x4F50CL) != 0L)     goto ERR;
+   if (((1uL<<(r%19uL)) & 0x4F50CuL) != 0uL)       goto LBL_ERR;
-   if (((1L<<(r%23)) & 0x7ACCA0L) != 0L)    goto ERR;
+   if (((1uL<<(r%23uL)) & 0x7ACCA0uL) != 0uL)      goto LBL_ERR;
-   if (((1L<<(r%29)) & 0xC2EDD0CL) != 0L)   goto ERR;
+   if (((1uL<<(r%29uL)) & 0xC2EDD0CuL) != 0uL)     goto LBL_ERR;
-   if (((1L<<(r%31)) & 0x6DE2B848L) != 0L)  goto ERR;
+   if (((1uL<<(r%31uL)) & 0x6DE2B848uL) != 0uL)    goto LBL_ERR;
 
    /* Final check - is sqr(sqrt(arg)) == arg ? */
    if ((res = mp_sqrt(arg, &t)) != MP_OKAY) {
-      goto ERR;
+      goto LBL_ERR;
    }
    if ((res = mp_sqr(&t, &t)) != MP_OKAY) {
-      goto ERR;
+      goto LBL_ERR;
    }
 
    *ret = (mp_cmp_mag(&t, arg) == MP_EQ) ? MP_YES : MP_NO;
-ERR:
+LBL_ERR:
    mp_clear(&t);
    return res;
 }

bn_mp_jacobi.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_JACOBI_C)
+#ifdef BN_MP_JACOBI_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,108 +9,25 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* computes the jacobi c = (a | n) (or Legendre if n is prime)
- * HAC pp. 73 Algorithm 2.149
+ * Kept for legacy reasons, please use mp_kronecker() instead
- * HAC is wrong here, as the special case of (0 | 1) is not
- * handled correctly.
  */
 int mp_jacobi(const mp_int *a, const mp_int *n, int *c)
 {
-   mp_int  a1, p1;
-   int     k, s, r, res;
-   mp_digit residue;
-
    /* if a < 0 return MP_VAL */
    if (mp_isneg(a) == MP_YES) {
       return MP_VAL;
    }
 
    /* if n <= 0 return MP_VAL */
-   if (mp_cmp_d(n, 0) != MP_GT) {
+   if (mp_cmp_d(n, 0uL) != MP_GT) {
       return MP_VAL;
    }
 
-   /* step 1. handle case of a == 0 */
+   return mp_kronecker(a, n, c);
-   if (mp_iszero(a) == MP_YES) {
-      /* special case of a == 0 and n == 1 */
-      if (mp_cmp_d(n, 1) == MP_EQ) {
-         *c = 1;
-      } else {
-         *c = 0;
-      }
-      return MP_OKAY;
-   }
-
-   /* step 2.  if a == 1, return 1 */
-   if (mp_cmp_d(a, 1) == MP_EQ) {
-      *c = 1;
-      return MP_OKAY;
-   }
-
-   /* default */
-   s = 0;
-
-   /* step 3.  write a = a1 * 2**k  */
-   if ((res = mp_init_copy(&a1, a)) != MP_OKAY) {
-      return res;
-   }
-
-   if ((res = mp_init(&p1)) != MP_OKAY) {
-      goto LBL_A1;
-   }
-
-   /* divide out larger power of two */
-   k = mp_cnt_lsb(&a1);
-   if ((res = mp_div_2d(&a1, k, &a1, NULL)) != MP_OKAY) {
-      goto LBL_P1;
-   }
-
-   /* step 4.  if e is even set s=1 */
-   if ((k & 1) == 0) {
-      s = 1;
-   } else {
-      /* else set s=1 if p = 1/7 (mod 8) or s=-1 if p = 3/5 (mod 8) */
-      residue = n->dp[0] & 7;
-
-      if ((residue == 1) || (residue == 7)) {
-         s = 1;
-      } else if ((residue == 3) || (residue == 5)) {
-         s = -1;
-      }
-   }
-
-   /* step 5.  if p == 3 (mod 4) *and* a1 == 3 (mod 4) then s = -s */
-   if (((n->dp[0] & 3) == 3) && ((a1.dp[0] & 3) == 3)) {
-      s = -s;
-   }
-
-   /* if a1 == 1 we're done */
-   if (mp_cmp_d(&a1, 1) == MP_EQ) {
-      *c = s;
-   } else {
-      /* n1 = n mod a1 */
-      if ((res = mp_mod(n, &a1, &p1)) != MP_OKAY) {
-         goto LBL_P1;
-      }
-      if ((res = mp_jacobi(&p1, &a1, &r)) != MP_OKAY) {
-         goto LBL_P1;
-      }
-      *c = s * r;
-   }
-
-   /* done */
-   res = MP_OKAY;
-LBL_P1:
-   mp_clear(&p1);
-LBL_A1:
-   mp_clear(&a1);
-   return res;
 }
 #endif
 

bn_mp_karatsuba_mul.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_KARATSUBA_MUL_C)
+#ifdef BN_MP_KARATSUBA_MUL_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* c = |a| * |b| using Karatsuba Multiplication using
@@ -60,7 +57,7 @@ int mp_karatsuba_mul(const mp_int *a, const mp_int *b, mp_int *c)
 
    /* init copy all the temps */
    if (mp_init_size(&x0, B) != MP_OKAY)
-      goto ERR;
+      goto LBL_ERR;
    if (mp_init_size(&x1, a->used - B) != MP_OKAY)
       goto X0;
    if (mp_init_size(&y0, B) != MP_OKAY)
@@ -164,7 +161,7 @@ X1:
    mp_clear(&x1);
 X0:
    mp_clear(&x0);
-ERR:
+LBL_ERR:
    return err;
 }
 #endif

bn_mp_karatsuba_sqr.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_KARATSUBA_SQR_C)
+#ifdef BN_MP_KARATSUBA_SQR_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* Karatsuba squaring, computes b = a*a using three
@@ -37,7 +34,7 @@ int mp_karatsuba_sqr(const mp_int *a, mp_int *b)
 
    /* init copy all the temps */
    if (mp_init_size(&x0, B) != MP_OKAY)
-      goto ERR;
+      goto LBL_ERR;
    if (mp_init_size(&x1, a->used - B) != MP_OKAY)
       goto X0;
 
@@ -117,7 +114,7 @@ X1:
    mp_clear(&x1);
 X0:
    mp_clear(&x0);
-ERR:
+LBL_ERR:
    return err;
 }
 #endif

bn_mp_lcm.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_LCM_C)
+#ifdef BN_MP_LCM_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* computes least common multiple as |a*b|/(a, b) */

bn_mp_lshd.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_LSHD_C)
+#ifdef BN_MP_LSHD_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* shift left a certain amount of digits */
@@ -24,6 +21,10 @@ int mp_lshd(mp_int *a, int b)
    if (b <= 0) {
       return MP_OKAY;
    }
+   /* no need to shift 0 around */
+   if (mp_iszero(a) == MP_YES) {
+      return MP_OKAY;
+   }
 
    /* grow to fit the new digits */
    if (a->alloc < (a->used + b)) {

bn_mp_mod.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_MOD_C)
+#ifdef BN_MP_MOD_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* c = a mod b, 0 <= c < b if b > 0, b < c <= 0 if b < 0 */

bn_mp_mod_2d.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_MOD_2D_C)
+#ifdef BN_MP_MOD_2D_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* calc a value mod 2**b */
@@ -27,7 +24,7 @@ int mp_mod_2d(const mp_int *a, int b, mp_int *c)
    }
 
    /* if the modulus is larger than the value than return */
-   if (b >= (int)(a->used * DIGIT_BIT)) {
+   if (b >= (a->used * DIGIT_BIT)) {
       res = mp_copy(a, c);
       return res;
    }
@@ -43,7 +40,7 @@ int mp_mod_2d(const mp_int *a, int b, mp_int *c)
    }
    /* clear the digit that is not completely outside/inside the modulus */
    c->dp[b / DIGIT_BIT] &=
-      (mp_digit)((((mp_digit) 1) << (((mp_digit) b) % DIGIT_BIT)) - ((mp_digit) 1));
+      ((mp_digit)1 << (mp_digit)(b % DIGIT_BIT)) - (mp_digit)1;
    mp_clamp(c);
    return MP_OKAY;
 }

bn_mp_mod_d.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_MOD_D_C)
+#ifdef BN_MP_MOD_D_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 int mp_mod_d(const mp_int *a, mp_digit b, mp_digit *c)

bn_mp_montgomery_calc_normalization.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_MONTGOMERY_CALC_NORMALIZATION_C)
+#ifdef BN_MP_MONTGOMERY_CALC_NORMALIZATION_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /*
@@ -33,7 +30,7 @@ int mp_montgomery_calc_normalization(mp_int *a, const mp_int *b)
          return res;
       }
    } else {
-      mp_set(a, 1);
+      mp_set(a, 1uL);
       bits = 1;
    }
 

bn_mp_montgomery_reduce.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_MONTGOMERY_REDUCE_C)
+#ifdef BN_MP_MONTGOMERY_REDUCE_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* computes xR**-1 == x (mod N) via Montgomery Reduction */
@@ -28,9 +25,10 @@ int mp_montgomery_reduce(mp_int *x, const mp_int *n, mp_digit rho)
     * are fixed up in the inner loop.
     */
    digs = (n->used * 2) + 1;
-   if ((digs < MP_WARRAY) &&
+   if ((digs < (int)MP_WARRAY) &&
+       (x->used <= (int)MP_WARRAY) &&
        (n->used <
-        (1 << ((CHAR_BIT * sizeof(mp_word)) - (2 * DIGIT_BIT))))) {
+        (int)(1u << (((size_t)CHAR_BIT * sizeof(mp_word)) - (2u * (size_t)DIGIT_BIT))))) {
       return fast_mp_montgomery_reduce(x, n, rho);
    }
 
@@ -72,19 +70,19 @@ int mp_montgomery_reduce(mp_int *x, const mp_int *n, mp_digit rho)
          for (iy = 0; iy < n->used; iy++) {
             /* compute product and sum */
             r       = ((mp_word)mu * (mp_word)*tmpn++) +
-                      (mp_word) u + (mp_word) *tmpx;
+                      (mp_word)u + (mp_word)*tmpx;
 
             /* get carry */
-            u       = (mp_digit)(r >> ((mp_word) DIGIT_BIT));
+            u       = (mp_digit)(r >> (mp_word)DIGIT_BIT);
 
             /* fix digit */
-            *tmpx++ = (mp_digit)(r & ((mp_word) MP_MASK));
+            *tmpx++ = (mp_digit)(r & (mp_word)MP_MASK);
          }
          /* At this point the ix'th digit of x should be zero */
 
 
          /* propagate carries upwards as required*/
-         while (u != 0) {
+         while (u != 0u) {
             *tmpx   += u;
             u        = *tmpx >> DIGIT_BIT;
             *tmpx++ &= MP_MASK;

bn_mp_montgomery_setup.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_MONTGOMERY_SETUP_C)
+#ifdef BN_MP_MONTGOMERY_SETUP_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* setups the montgomery reduction stuff */
@@ -30,24 +27,24 @@ int mp_montgomery_setup(const mp_int *n, mp_digit *rho)
     */
    b = n->dp[0];
 
-   if ((b & 1) == 0) {
+   if ((b & 1u) == 0u) {
       return MP_VAL;
    }
 
-   x = (((b + 2) & 4) << 1) + b; /* here x*a==1 mod 2**4 */
+   x = (((b + 2u) & 4u) << 1) + b; /* here x*a==1 mod 2**4 */
-   x *= 2 - (b * x);             /* here x*a==1 mod 2**8 */
+   x *= 2u - (b * x);              /* here x*a==1 mod 2**8 */
 #if !defined(MP_8BIT)
-   x *= 2 - (b * x);             /* here x*a==1 mod 2**16 */
+   x *= 2u - (b * x);              /* here x*a==1 mod 2**16 */
 #endif
 #if defined(MP_64BIT) || !(defined(MP_8BIT) || defined(MP_16BIT))
-   x *= 2 - (b * x);             /* here x*a==1 mod 2**32 */
+   x *= 2u - (b * x);              /* here x*a==1 mod 2**32 */
 #endif
 #ifdef MP_64BIT
-   x *= 2 - (b * x);             /* here x*a==1 mod 2**64 */
+   x *= 2u - (b * x);              /* here x*a==1 mod 2**64 */
 #endif
 
    /* rho = -1/m mod b */
-   *rho = (mp_digit)(((mp_word)1 << ((mp_word) DIGIT_BIT)) - x) & MP_MASK;
+   *rho = (mp_digit)(((mp_word)1 << (mp_word)DIGIT_BIT) - x) & MP_MASK;
 
    return MP_OKAY;
 }

bn_mp_mul.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_MUL_C)
+#ifdef BN_MP_MUL_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,18 +9,10 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* high level multiplication (handles sign) */
-
-#define BN_MP_TOOM_MUL_C
-#define BN_MP_KARATSUBA_MUL_C
-#define BN_FAST_S_MP_MUL_DIGS_C
-#define BN_S_MP_MUL_DIGS_C
 int mp_mul(const mp_int *a, const mp_int *b, mp_int *c)
 {
    int     res, neg;
@@ -48,9 +40,9 @@ int mp_mul(const mp_int *a, const mp_int *b, mp_int *c)
          int     digs = a->used + b->used + 1;
 
 #ifdef BN_FAST_S_MP_MUL_DIGS_C
-         if ((digs < MP_WARRAY) &&
+         if ((digs < (int)MP_WARRAY) &&
              (MIN(a->used, b->used) <=
-              (1 << ((CHAR_BIT * sizeof(mp_word)) - (2 * DIGIT_BIT))))) {
+              (int)(1u << (((size_t)CHAR_BIT * sizeof(mp_word)) - (2u * (size_t)DIGIT_BIT))))) {
             res = fast_s_mp_mul_digs(a, b, c, digs);
          } else
 #endif

bn_mp_mul_2.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_MUL_2_C)
+#ifdef BN_MP_MUL_2_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* b = a*2 */
@@ -46,10 +43,10 @@ int mp_mul_2(const mp_int *a, mp_int *b)
          /* get what will be the *next* carry bit from the
           * MSB of the current digit
           */
-         rr = *tmpa >> ((mp_digit)(DIGIT_BIT - 1));
+         rr = *tmpa >> (mp_digit)(DIGIT_BIT - 1);
 
          /* now shift up this digit, add in the carry [from the previous] */
-         *tmpb++ = ((*tmpa++ << ((mp_digit)1)) | r) & MP_MASK;
+         *tmpb++ = ((*tmpa++ << 1uL) | r) & MP_MASK;
 
          /* copy the carry that would be from the source
           * digit into the next iteration
@@ -58,7 +55,7 @@ int mp_mul_2(const mp_int *a, mp_int *b)
       }
 
       /* new leading digit? */
-      if (r != 0) {
+      if (r != 0u) {
          /* add a MSB which is always 1 at this point */
          *tmpb = 1;
          ++(b->used);

bn_mp_mul_2d.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_MUL_2D_C)
+#ifdef BN_MP_MUL_2D_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* shift left by a certain bit count */
@@ -28,14 +25,14 @@ int mp_mul_2d(const mp_int *a, int b, mp_int *c)
       }
    }
 
-   if (c->alloc < (int)(c->used + (b / DIGIT_BIT) + 1)) {
+   if (c->alloc < (c->used + (b / DIGIT_BIT) + 1)) {
       if ((res = mp_grow(c, c->used + (b / DIGIT_BIT) + 1)) != MP_OKAY) {
          return res;
       }
    }
 
    /* shift by as many digits in the bit count */
-   if (b >= (int)DIGIT_BIT) {
+   if (b >= DIGIT_BIT) {
       if ((res = mp_lshd(c, b / DIGIT_BIT)) != MP_OKAY) {
          return res;
       }
@@ -43,15 +40,15 @@ int mp_mul_2d(const mp_int *a, int b, mp_int *c)
 
    /* shift any bit count < DIGIT_BIT */
    d = (mp_digit)(b % DIGIT_BIT);
-   if (d != 0) {
+   if (d != 0u) {
       mp_digit *tmpc, shift, mask, r, rr;
       int x;
 
       /* bitmask for carries */
-      mask = (((mp_digit)1) << d) - 1;
+      mask = ((mp_digit)1 << d) - (mp_digit)1;
 
       /* shift for msbs */
-      shift = DIGIT_BIT - d;
+      shift = (mp_digit)DIGIT_BIT - d;
 
       /* alias */
       tmpc = c->dp;
@@ -71,7 +68,7 @@ int mp_mul_2d(const mp_int *a, int b, mp_int *c)
       }
 
       /* set final carry */
-      if (r != 0) {
+      if (r != 0u) {
          c->dp[(c->used)++] = r;
       }
    }

bn_mp_mul_d.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_MUL_D_C)
+#ifdef BN_MP_MUL_D_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* multiply by a digit */
@@ -50,10 +47,10 @@ int mp_mul_d(const mp_int *a, mp_digit b, mp_int *c)
       r       = (mp_word)u + ((mp_word)*tmpa++ * (mp_word)b);
 
       /* mask off higher bits to get a single digit */
-      *tmpc++ = (mp_digit)(r & ((mp_word)MP_MASK));
+      *tmpc++ = (mp_digit)(r & (mp_word)MP_MASK);
 
       /* send carry into next iteration */
-      u       = (mp_digit)(r >> ((mp_word)DIGIT_BIT));
+      u       = (mp_digit)(r >> (mp_word)DIGIT_BIT);
    }
 
    /* store final carry [if any] and increment ix offset  */

bn_mp_mulmod.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_MULMOD_C)
+#ifdef BN_MP_MULMOD_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* d = a * b (mod c) */

bn_mp_n_root.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_N_ROOT_C)
+#ifdef BN_MP_N_ROOT_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* wrapper function for mp_n_root_ex()

bn_mp_n_root_ex.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_N_ROOT_EX_C)
+#ifdef BN_MP_N_ROOT_EX_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* find the n'th root of an integer
@@ -31,7 +28,7 @@ int mp_n_root_ex(const mp_int *a, mp_digit b, mp_int *c, int fast)
    int     res;
 
    /* input must be positive if b is even */
-   if (((b & 1) == 0) && (a->sign == MP_NEG)) {
+   if (((b & 1u) == 0u) && (a->sign == MP_NEG)) {
       return MP_VAL;
    }
 
@@ -52,7 +49,7 @@ int mp_n_root_ex(const mp_int *a, mp_digit b, mp_int *c, int fast)
    a_.sign = MP_ZPOS;
 
    /* t2 = 2 */
-   mp_set(&t2, 2);
+   mp_set(&t2, 2uL);
 
    do {
       /* t1 = t2 */
@@ -63,7 +60,7 @@ int mp_n_root_ex(const mp_int *a, mp_digit b, mp_int *c, int fast)
       /* t2 = t1 - ((t1**b - a) / (b * t1**(b-1))) */
 
       /* t3 = t1**(b-1) */
-      if ((res = mp_expt_d_ex(&t1, b - 1, &t3, fast)) != MP_OKAY) {
+      if ((res = mp_expt_d_ex(&t1, b - 1u, &t3, fast)) != MP_OKAY) {
          goto LBL_T3;
       }
 
@@ -101,7 +98,7 @@ int mp_n_root_ex(const mp_int *a, mp_digit b, mp_int *c, int fast)
       }
 
       if (mp_cmp(&t2, &a_) == MP_GT) {
-         if ((res = mp_sub_d(&t1, 1, &t1)) != MP_OKAY) {
+         if ((res = mp_sub_d(&t1, 1uL, &t1)) != MP_OKAY) {
             goto LBL_T3;
          }
       } else {

bn_mp_neg.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_NEG_C)
+#ifdef BN_MP_NEG_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* b = -a */

bn_mp_or.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_OR_C)
+#ifdef BN_MP_OR_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* OR two ints together */

bn_mp_prime_fermat.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_PRIME_FERMAT_C)
+#ifdef BN_MP_PRIME_FERMAT_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* performs one Fermat test.
@@ -32,7 +29,7 @@ int mp_prime_fermat(const mp_int *a, const mp_int *b, int *result)
    *result = MP_NO;
 
    /* ensure b > 1 */
-   if (mp_cmp_d(b, 1) != MP_GT) {
+   if (mp_cmp_d(b, 1uL) != MP_GT) {
       return MP_VAL;
    }
 

bn_mp_prime_is_divisible.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_PRIME_IS_DIVISIBLE_C)
+#ifdef BN_MP_PRIME_IS_DIVISIBLE_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* determines if an integers is divisible by one
@@ -35,7 +32,7 @@ int mp_prime_is_divisible(const mp_int *a, int *result)
       }
 
       /* is the residue zero? */
-      if (res == 0) {
+      if (res == 0u) {
          *result = MP_YES;
          return MP_OKAY;
       }

bn_mp_prime_is_prime.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_PRIME_IS_PRIME_C)
+#ifdef BN_MP_PRIME_IS_PRIME_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,39 +9,72 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
-/* performs a variable number of rounds of Miller-Rabin
+/* portable integer log of two with small footprint */
- *
+static unsigned int s_floor_ilog2(int value)
- * Probability of error after t rounds is no more than
+{
+   unsigned int r = 0;
+   while ((value >>= 1) != 0) {
+      r++;
+   }
+   return r;
+}
+
 
- *
- * Sets result to 1 if probably prime, 0 otherwise
- */
 int mp_prime_is_prime(const mp_int *a, int t, int *result)
 {
    mp_int  b;
-   int     ix, err, res;
+   int     ix, err, res, p_max = 0, size_a, len;
+   unsigned int fips_rand, mask;
 
    /* default to no */
    *result = MP_NO;
 
    /* valid value of t? */
-   if ((t <= 0) || (t > PRIME_SIZE)) {
+   if (t > PRIME_SIZE) {
       return MP_VAL;
    }
 
+   /* Some shortcuts */
+   /* N > 3 */
+   if (a->used == 1) {
+      if ((a->dp[0] == 0u) || (a->dp[0] == 1u)) {
+         *result = 0;
+         return MP_OKAY;
+      }
+      if (a->dp[0] == 2u) {
+         *result = 1;
+         return MP_OKAY;
+      }
+   }
+
+   /* N must be odd */
+   if (mp_iseven(a) == MP_YES) {
+      return MP_OKAY;
+   }
+   /* N is not a perfect square: floor(sqrt(N))^2 != N */
+   if ((err = mp_is_square(a, &res)) != MP_OKAY) {
+      return err;
+   }
+   if (res != 0) {
+      return MP_OKAY;
+   }
+
    /* is the input equal to one of the primes in the table? */
    for (ix = 0; ix < PRIME_SIZE; ix++) {
       if (mp_cmp_d(a, ltm_prime_tab[ix]) == MP_EQ) {
-         *result = 1;
+         *result = MP_YES;
          return MP_OKAY;
       }
    }
+#ifdef MP_8BIT
+   /* The search in the loop above was exhaustive in this case */
+   if ((a->used == 1) && (PRIME_SIZE >= 31)) {
+      return MP_OKAY;
+   }
+#endif
 
    /* first perform trial division */
    if ((err = mp_prime_is_divisible(a, &res)) != MP_OKAY) {
@@ -53,22 +86,274 @@ int mp_prime_is_prime(const mp_int *a, int t, int *result)
       return MP_OKAY;
    }
 
-   /* now perform the miller-rabin rounds */
+   /*
-   if ((err = mp_init(&b)) != MP_OKAY) {
+       Run the Miller-Rabin test with base 2 for the BPSW test.
+    */
+   if ((err = mp_init_set(&b, 2uL)) != MP_OKAY) {
       return err;
    }
 
-   for (ix = 0; ix < t; ix++) {
+   if ((err = mp_prime_miller_rabin(a, &b, &res)) != MP_OKAY) {
-      /* set the prime */
+      goto LBL_B;
-      mp_set(&b, ltm_prime_tab[ix]);
+   }
+   if (res == MP_NO) {
+      goto LBL_B;
+   }
+   /*
+      Rumours have it that Mathematica does a second M-R test with base 3.
+      Other rumours have it that their strong L-S test is slightly different.
+      It does not hurt, though, beside a bit of extra runtime.
+   */
+   b.dp[0]++;
+   if ((err = mp_prime_miller_rabin(a, &b, &res)) != MP_OKAY) {
+      goto LBL_B;
+   }
+   if (res == MP_NO) {
+      goto LBL_B;
+   }
 
-      if ((err = mp_prime_miller_rabin(a, &b, &res)) != MP_OKAY) {
+   /*
+    * Both, the Frobenius-Underwood test and the the Lucas-Selfridge test are quite
+    * slow so if speed is an issue, define LTM_USE_FIPS_ONLY to use M-R tests with
+    * bases 2, 3 and t random bases.
+    */
+#ifndef LTM_USE_FIPS_ONLY
+   if (t >= 0) {
+      /*
+       * Use a Frobenius-Underwood test instead of the Lucas-Selfridge test for
+       * MP_8BIT (It is unknown if the Lucas-Selfridge test works with 16-bit
+       * integers but the necesssary analysis is on the todo-list).
+       */
+#if defined (MP_8BIT) || defined (LTM_USE_FROBENIUS_TEST)
+      err = mp_prime_frobenius_underwood(a, &res);
+      if ((err != MP_OKAY) && (err != MP_ITER)) {
+         goto LBL_B;
+      }
+      if (res == MP_NO) {
+         goto LBL_B;
+      }
+#else
+      if ((err = mp_prime_strong_lucas_selfridge(a, &res)) != MP_OKAY) {
+         goto LBL_B;
+      }
+      if (res == MP_NO) {
+         goto LBL_B;
+      }
+#endif
+   }
+#endif
+
+   /* run at least one Miller-Rabin test with a random base */
+   if (t == 0) {
+      t = 1;
+   }
+
+   /*
+      abs(t) extra rounds of M-R to extend the range of primes it can find if t < 0.
+      Only recommended if the input range is known to be < 3317044064679887385961981
+
+      It uses the bases for a deterministic M-R test if input < 3317044064679887385961981
+      The caller has to check the size.
+
+      Not for cryptographic use because with known bases strong M-R pseudoprimes can
+      be constructed. Use at least one M-R test with a random base (t >= 1).
+
+      The 1119 bit large number
+
+      80383745745363949125707961434194210813883768828755814583748891752229742737653\
+      33652186502336163960045457915042023603208766569966760987284043965408232928738\
+      79185086916685732826776177102938969773947016708230428687109997439976544144845\
+      34115587245063340927902227529622941498423068816854043264575340183297861112989\
+      60644845216191652872597534901
+
+      has been constructed by F. Arnault (F. Arnault, "Rabin-Miller primality test:
+      composite numbers which pass it.",  Mathematics of Computation, 1995, 64. Jg.,
+      Nr. 209, S. 355-361), is a semiprime with the two factors
+
+      40095821663949960541830645208454685300518816604113250877450620473800321707011\
+      96242716223191597219733582163165085358166969145233813917169287527980445796800\
+      452592031836601
+
+      20047910831974980270915322604227342650259408302056625438725310236900160853505\
+      98121358111595798609866791081582542679083484572616906958584643763990222898400\
+      226296015918301
+
+      and it is a strong pseudoprime to all forty-six prime M-R bases up to 200
+
+      It does not fail the strong Bailley-PSP test as implemented here, it is just
+      given as an example, if not the reason to use the BPSW-test instead of M-R-tests
+      with a sequence of primes 2...n.
+
+   */
+   if (t < 0) {
+      t = -t;
+      /*
+          Sorenson, Jonathan; Webster, Jonathan (2015).
+           "Strong Pseudoprimes to Twelve Prime Bases".
+       */
+      /* 0x437ae92817f9fc85b7e5 = 318665857834031151167461 */
+      if ((err =   mp_read_radix(&b, "437ae92817f9fc85b7e5", 16)) != MP_OKAY) {
          goto LBL_B;
       }
 
-      if (res == MP_NO) {
+      if (mp_cmp(a, &b) == MP_LT) {
+         p_max = 12;
+      } else {
+         /* 0x2be6951adc5b22410a5fd = 3317044064679887385961981 */
+         if ((err = mp_read_radix(&b, "2be6951adc5b22410a5fd", 16)) != MP_OKAY) {
+            goto LBL_B;
+         }
+
+         if (mp_cmp(a, &b) == MP_LT) {
+            p_max = 13;
+         } else {
+            err = MP_VAL;
+            goto LBL_B;
+         }
+      }
+
+      /* for compatibility with the current API (well, compatible within a sign's width) */
+      if (p_max < t) {
+         p_max = t;
+      }
+
+      if (p_max > PRIME_SIZE) {
+         err = MP_VAL;
          goto LBL_B;
       }
+      /* we did bases 2 and 3  already, skip them */
+      for (ix = 2; ix < p_max; ix++) {
+         mp_set(&b, ltm_prime_tab[ix]);
+         if ((err = mp_prime_miller_rabin(a, &b, &res)) != MP_OKAY) {
+            goto LBL_B;
+         }
+         if (res == MP_NO) {
+            goto LBL_B;
+         }
+      }
+   }
+   /*
+       Do "t" M-R tests with random bases between 3 and "a".
+       See Fips 186.4 p. 126ff
+   */
+   else if (t > 0) {
+      /*
+       * The mp_digit's have a defined bit-size but the size of the
+       * array a.dp is a simple 'int' and this library can not assume full
+       * compliance to the current C-standard (ISO/IEC 9899:2011) because
+       * it gets used for small embeded processors, too. Some of those MCUs
+       * have compilers that one cannot call standard compliant by any means.
+       * Hence the ugly type-fiddling in the following code.
+       */
+      size_a = mp_count_bits(a);
+      mask = (1u << s_floor_ilog2(size_a)) - 1u;
+      /*
+         Assuming the General Rieman hypothesis (never thought to write that in a
+         comment) the upper bound can be lowered to  2*(log a)^2.
+         E. Bach, "Explicit bounds for primality testing and related problems,"
+         Math. Comp. 55 (1990), 355-380.
+
+            size_a = (size_a/10) * 7;
+            len = 2 * (size_a * size_a);
+
+         E.g.: a number of size 2^2048 would be reduced to the upper limit
+
+            floor(2048/10)*7 = 1428
+            2 * 1428^2       = 4078368
+
+         (would have been ~4030331.9962 with floats and natural log instead)
+         That number is smaller than 2^28, the default bit-size of mp_digit.
+      */
+
+      /*
+        How many tests, you might ask? Dana Jacobsen of Math::Prime::Util fame
+        does exactly 1. In words: one. Look at the end of _GMP_is_prime() in
+        Math-Prime-Util-GMP-0.50/primality.c if you do not believe it.
+
+        The function mp_rand() goes to some length to use a cryptographically
+        good PRNG. That also means that the chance to always get the same base
+        in the loop is non-zero, although very low.
+        If the BPSW test and/or the addtional Frobenious test have been
+        performed instead of just the Miller-Rabin test with the bases 2 and 3,
+        a single extra test should suffice, so such a very unlikely event
+        will not do much harm.
+
+        To preemptivly answer the dangling question: no, a witness does not
+        need to be prime.
+      */
+      for (ix = 0; ix < t; ix++) {
+         /* mp_rand() guarantees the first digit to be non-zero */
+         if ((err = mp_rand(&b, 1)) != MP_OKAY) {
+            goto LBL_B;
+         }
+         /*
+          * Reduce digit before casting because mp_digit might be bigger than
+          * an unsigned int and "mask" on the other side is most probably not.
+          */
+         fips_rand = (unsigned int)(b.dp[0] & (mp_digit) mask);
+#ifdef MP_8BIT
+         /*
+          * One 8-bit digit is too small, so concatenate two if the size of
+          * unsigned int allows for it.
+          */
+         if (((sizeof(unsigned int) * CHAR_BIT)/2) >= (sizeof(mp_digit) * CHAR_BIT)) {
+            if ((err = mp_rand(&b, 1)) != MP_OKAY) {
+               goto LBL_B;
+            }
+            fips_rand <<= sizeof(mp_digit) * CHAR_BIT;
+            fips_rand |= (unsigned int) b.dp[0];
+            fips_rand &= mask;
+         }
+#endif
+         if (fips_rand > (unsigned int)(INT_MAX - DIGIT_BIT)) {
+            len = INT_MAX / DIGIT_BIT;
+         } else {
+            len = (((int)fips_rand + DIGIT_BIT) / DIGIT_BIT);
+         }
+         /*  Unlikely. */
+         if (len < 0) {
+            ix--;
+            continue;
+         }
+         /*
+          * As mentioned above, one 8-bit digit is too small and
+          * although it can only happen in the unlikely case that
+          * an "unsigned int" is smaller than 16 bit a simple test
+          * is cheap and the correction even cheaper.
+          */
+#ifdef MP_8BIT
+         /* All "a" < 2^8 have been caught before */
+         if (len == 1) {
+            len++;
+         }
+#endif
+         if ((err = mp_rand(&b, len)) != MP_OKAY) {
+            goto LBL_B;
+         }
+         /*
+          * That number might got too big and the witness has to be
+          * smaller than or equal to "a"
+          */
+         len = mp_count_bits(&b);
+         if (len > size_a) {
+            len = len - size_a;
+            if ((err = mp_div_2d(&b, len, &b, NULL)) != MP_OKAY) {
+               goto LBL_B;
+            }
+         }
+
+         /* Although the chance for b <= 3 is miniscule, try again. */
+         if (mp_cmp_d(&b, 3uL) != MP_GT) {
+            ix--;
+            continue;
+         }
+         if ((err = mp_prime_miller_rabin(a, &b, &res)) != MP_OKAY) {
+            goto LBL_B;
+         }
+         if (res == MP_NO) {
+            goto LBL_B;
+         }
+      }
    }
 
    /* passed the test */
@@ -77,6 +362,7 @@ LBL_B:
    mp_clear(&b);
    return err;
 }
+
 #endif
 
 /* ref:         $Format:%D$ */

bn_mp_prime_miller_rabin.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_PRIME_MILLER_RABIN_C)
+#ifdef BN_MP_PRIME_MILLER_RABIN_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* Miller-Rabin test of "a" to the base of "b" as described in
@@ -31,7 +28,7 @@ int mp_prime_miller_rabin(const mp_int *a, const mp_int *b, int *result)
    *result = MP_NO;
 
    /* ensure b > 1 */
-   if (mp_cmp_d(b, 1) != MP_GT) {
+   if (mp_cmp_d(b, 1uL) != MP_GT) {
       return MP_VAL;
    }
 
@@ -39,7 +36,7 @@ int mp_prime_miller_rabin(const mp_int *a, const mp_int *b, int *result)
    if ((err = mp_init_copy(&n1, a)) != MP_OKAY) {
       return err;
    }
-   if ((err = mp_sub_d(&n1, 1, &n1)) != MP_OKAY) {
+   if ((err = mp_sub_d(&n1, 1uL, &n1)) != MP_OKAY) {
       goto LBL_N1;
    }
 
@@ -67,7 +64,7 @@ int mp_prime_miller_rabin(const mp_int *a, const mp_int *b, int *result)
    }
 
    /* if y != 1 and y != n1 do */
-   if ((mp_cmp_d(&y, 1) != MP_EQ) && (mp_cmp(&y, &n1) != MP_EQ)) {
+   if ((mp_cmp_d(&y, 1uL) != MP_EQ) && (mp_cmp(&y, &n1) != MP_EQ)) {
       j = 1;
       /* while j <= s-1 and y != n1 */
       while ((j <= (s - 1)) && (mp_cmp(&y, &n1) != MP_EQ)) {
@@ -76,7 +73,7 @@ int mp_prime_miller_rabin(const mp_int *a, const mp_int *b, int *result)
          }
 
          /* if y == 1 then composite */
-         if (mp_cmp_d(&y, 1) == MP_EQ) {
+         if (mp_cmp_d(&y, 1uL) == MP_EQ) {
             goto LBL_Y;
          }
 

bn_mp_prime_next_prime.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_PRIME_NEXT_PRIME_C)
+#ifdef BN_MP_PRIME_NEXT_PRIME_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* finds the next prime after the number "a" using "t" trials
@@ -26,11 +23,6 @@ int mp_prime_next_prime(mp_int *a, int t, int bbs_style)
    mp_digit res_tab[PRIME_SIZE], step, kstep;
    mp_int   b;
 
-   /* ensure t is valid */
-   if ((t <= 0) || (t > PRIME_SIZE)) {
-      return MP_VAL;
-   }
-
    /* force positive */
    a->sign = MP_ZPOS;
 
@@ -46,10 +38,10 @@ int mp_prime_next_prime(mp_int *a, int t, int bbs_style)
                 * however, the prime must be
                 * congruent to 3 mod 4
                 */
-               if ((ltm_prime_tab[x + 1] & 3) != 3) {
+               if ((ltm_prime_tab[x + 1] & 3u) != 3u) {
                   /* scan upwards for a prime congruent to 3 mod 4 */
                   for (y = x + 1; y < PRIME_SIZE; y++) {
-                     if ((ltm_prime_tab[y] & 3) == 3) {
+                     if ((ltm_prime_tab[y] & 3u) == 3u) {
                         mp_set(a, ltm_prime_tab[y]);
                         return MP_OKAY;
                      }
@@ -62,8 +54,8 @@ int mp_prime_next_prime(mp_int *a, int t, int bbs_style)
          }
       }
       /* at this point a maybe 1 */
-      if (mp_cmp_d(a, 1) == MP_EQ) {
+      if (mp_cmp_d(a, 1uL) == MP_EQ) {
-         mp_set(a, 2);
+         mp_set(a, 2uL);
          return MP_OKAY;
       }
       /* fall through to the sieve */
@@ -80,15 +72,15 @@ int mp_prime_next_prime(mp_int *a, int t, int bbs_style)
 
    if (bbs_style == 1) {
       /* if a mod 4 != 3 subtract the correct value to make it so */
-      if ((a->dp[0] & 3) != 3) {
+      if ((a->dp[0] & 3u) != 3u) {
-         if ((err = mp_sub_d(a, (a->dp[0] & 3) + 1, a)) != MP_OKAY) {
+         if ((err = mp_sub_d(a, (a->dp[0] & 3u) + 1u, a)) != MP_OKAY) {
             return err;
          };
       }
    } else {
       if (mp_iseven(a) == MP_YES) {
          /* force odd */
-         if ((err = mp_sub_d(a, 1, a)) != MP_OKAY) {
+         if ((err = mp_sub_d(a, 1uL, a)) != MP_OKAY) {
             return err;
          }
       }
@@ -127,11 +119,11 @@ int mp_prime_next_prime(mp_int *a, int t, int bbs_style)
             }
 
             /* set flag if zero */
-            if (res_tab[x] == 0) {
+            if (res_tab[x] == 0u) {
                y = 1;
             }
          }
-      } while ((y == 1) && (step < ((((mp_digit)1) << DIGIT_BIT) - kstep)));
+      } while ((y == 1) && (step < (((mp_digit)1 << DIGIT_BIT) - kstep)));
 
       /* add the step */
       if ((err = mp_add_d(a, step, a)) != MP_OKAY) {
@@ -139,21 +131,13 @@ int mp_prime_next_prime(mp_int *a, int t, int bbs_style)
       }
 
       /* if didn't pass sieve and step == MAX then skip test */
-      if ((y == 1) && (step >= ((((mp_digit)1) << DIGIT_BIT) - kstep))) {
+      if ((y == 1) && (step >= (((mp_digit)1 << DIGIT_BIT) - kstep))) {
          continue;
       }
 
-      /* is this prime? */
+      if ((err = mp_prime_is_prime(a, t, &res)) != MP_OKAY) {
-      for (x = 0; x < t; x++) {
+         goto LBL_ERR;
-         mp_set(&b, ltm_prime_tab[x]);
-         if ((err = mp_prime_miller_rabin(a, &b, &res)) != MP_OKAY) {
-            goto LBL_ERR;
-         }
-         if (res == MP_NO) {
-            break;
-         }
       }
-
       if (res == MP_YES) {
          break;
       }

bn_mp_prime_rabin_miller_trials.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_PRIME_RABIN_MILLER_TRIALS_C)
+#ifdef BN_MP_PRIME_RABIN_MILLER_TRIALS_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,27 +9,31 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 
 static const struct {
    int k, t;
 } sizes[] = {
-   {   128,    28 },
+   {    80,    -1 }, /* Use deterministic algorithm for size <= 80 bits */
+   {    81,    39 },
+   {    96,    37 },
+   {   128,    32 },
+   {   160,    27 },
+   {   192,    21 },
    {   256,    16 },
    {   384,    10 },
    {   512,     7 },
    {   640,     6 },
    {   768,     5 },
    {   896,     4 },
-   {  1024,     4 }
+   {  1024,     4 },
+   {  2048,     2 },
+   {  4096,     1 },
 };
 
-/* returns # of RM trials required for a given bit size */
+/* returns # of RM trials required for a given bit size and max. error of 2^(-96)*/
 int mp_prime_rabin_miller_trials(int size)
 {
    int x;

bn_mp_prime_random_ex.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_PRIME_RANDOM_EX_C)
+#ifdef BN_MP_PRIME_RANDOM_EX_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* makes a truly random prime of a given size (bits),
@@ -49,7 +46,7 @@ int mp_prime_random_ex(mp_int *a, int t, int size, int flags, ltm_prime_callback
    bsize = (size>>3) + ((size&7)?1:0);
 
    /* we need a buffer of bsize bytes */
-   tmp = OPT_CAST(unsigned char) XMALLOC(bsize);
+   tmp = OPT_CAST(unsigned char) XMALLOC((size_t)bsize);
    if (tmp == NULL) {
       return MP_MEM;
    }
@@ -86,12 +83,12 @@ int mp_prime_random_ex(mp_int *a, int t, int size, int flags, ltm_prime_callback
       tmp[bsize-1]             |= maskOR_lsb;
 
       /* read it in */
-      if ((err = mp_read_unsigned_bin(a, tmp, bsize)) != MP_OKAY)     {
+      if ((err = mp_read_unsigned_bin(a, tmp, bsize)) != MP_OKAY) {
          goto error;
       }
 
       /* is it prime? */
-      if ((err = mp_prime_is_prime(a, t, &res)) != MP_OKAY)           {
+      if ((err = mp_prime_is_prime(a, t, &res)) != MP_OKAY) {
          goto error;
       }
       if (res == MP_NO) {
@@ -100,15 +97,15 @@ int mp_prime_random_ex(mp_int *a, int t, int size, int flags, ltm_prime_callback
 
       if ((flags & LTM_PRIME_SAFE) != 0) {
          /* see if (a-1)/2 is prime */
-         if ((err = mp_sub_d(a, 1, a)) != MP_OKAY)                    {
+         if ((err = mp_sub_d(a, 1uL, a)) != MP_OKAY) {
             goto error;
          }
-         if ((err = mp_div_2(a, a)) != MP_OKAY)                       {
+         if ((err = mp_div_2(a, a)) != MP_OKAY) {
             goto error;
          }
 
          /* is it prime? */
-         if ((err = mp_prime_is_prime(a, t, &res)) != MP_OKAY)        {
+         if ((err = mp_prime_is_prime(a, t, &res)) != MP_OKAY) {
             goto error;
          }
       }
@@ -116,10 +113,10 @@ int mp_prime_random_ex(mp_int *a, int t, int size, int flags, ltm_prime_callback
 
    if ((flags & LTM_PRIME_SAFE) != 0) {
       /* restore a to the original value */
-      if ((err = mp_mul_2(a, a)) != MP_OKAY)                          {
+      if ((err = mp_mul_2(a, a)) != MP_OKAY) {
          goto error;
       }
-      if ((err = mp_add_d(a, 1, a)) != MP_OKAY)                       {
+      if ((err = mp_add_d(a, 1uL, a)) != MP_OKAY) {
          goto error;
       }
    }

bn_mp_radix_size.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined( BN_MP_RADIX_SIZE_C)
+#ifdef BN_MP_RADIX_SIZE_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* returns size of ASCII reprensentation */

bn_mp_radix_smap.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_RADIX_SMAP_C)
+#ifdef BN_MP_RADIX_SMAP_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,14 +9,25 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* chars used in radix conversions */
-const char *mp_s_rmap = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz+/";
+const char *const mp_s_rmap = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz+/";
+const uint8_t mp_s_rmap_reverse[] = {
+   0xff, 0xff, 0xff, 0x3e, 0xff, 0xff, 0xff, 0x3f, /* ()*+,-./ */
+   0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 01234567 */
+   0x08, 0x09, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 89:;<=>? */
+   0xff, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, /* @ABCDEFG */
+   0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, /* HIJKLMNO */
+   0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, /* PQRSTUVW */
+   0x21, 0x22, 0x23, 0xff, 0xff, 0xff, 0xff, 0xff, /* XYZ[\]^_ */
+   0xff, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, /* `abcdefg */
+   0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, /* hijklmno */
+   0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, /* pqrstuvw */
+   0x3b, 0x3c, 0x3d, 0xff, 0xff, 0xff, 0xff, 0xff, /* xyz{|}~. */
+};
+const size_t mp_s_rmap_reverse_sz = sizeof(mp_s_rmap_reverse);
 #endif
 
 /* ref:         $Format:%D$ */

bn_mp_rand.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_RAND_C)
+#ifdef BN_MP_RAND_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,36 +9,174 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
-#if MP_GEN_RANDOM_MAX == 0xffffffff
+/* First the OS-specific special cases
-#define MP_GEN_RANDOM_SHIFT  32
+ * - *BSD
-#elif MP_GEN_RANDOM_MAX == 32767
+ * - Windows
-/* SHRT_MAX */
+ */
-#define MP_GEN_RANDOM_SHIFT  15
+#if defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) || defined(__DragonFly__)
-#elif MP_GEN_RANDOM_MAX == 2147483647
+#define MP_ARC4RANDOM
-/* INT_MAX */
+#define MP_GEN_RANDOM_MAX     0xffffffffu
-#define MP_GEN_RANDOM_SHIFT  31
+#define MP_GEN_RANDOM_SHIFT   32
-#elif !defined(MP_GEN_RANDOM_SHIFT)
-#error Thou shalt define their own valid MP_GEN_RANDOM_SHIFT
-#endif
 
-/* makes a pseudo-random int of a given size */
+static int s_read_arc4random(mp_digit *p)
-static mp_digit s_gen_random(void)
 {
    mp_digit d = 0, msk = 0;
    do {
       d <<= MP_GEN_RANDOM_SHIFT;
-      d |= ((mp_digit) MP_GEN_RANDOM());
+      d |= ((mp_digit) arc4random());
       msk <<= MP_GEN_RANDOM_SHIFT;
       msk |= (MP_MASK & MP_GEN_RANDOM_MAX);
    } while ((MP_MASK & msk) != MP_MASK);
-   d &= MP_MASK;
+   *p = d;
-   return d;
+   return MP_OKAY;
+}
+#endif
+
+#if defined(_WIN32) || defined(_WIN32_WCE)
+#define MP_WIN_CSP
+
+#ifndef _WIN32_WINNT
+#define _WIN32_WINNT 0x0400
+#endif
+#ifdef _WIN32_WCE
+#define UNDER_CE
+#define ARM
+#endif
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <wincrypt.h>
+
+static HCRYPTPROV hProv = 0;
+
+static void s_cleanup_win_csp(void)
+{
+   CryptReleaseContext(hProv, 0);
+   hProv = 0;
+}
+
+static int s_read_win_csp(mp_digit *p)
+{
+   int ret = -1;
+   if (hProv == 0) {
+      if (!CryptAcquireContext(&hProv, NULL, MS_DEF_PROV, PROV_RSA_FULL,
+                               (CRYPT_VERIFYCONTEXT | CRYPT_MACHINE_KEYSET)) &&
+          !CryptAcquireContext(&hProv, NULL, MS_DEF_PROV, PROV_RSA_FULL,
+                               CRYPT_VERIFYCONTEXT | CRYPT_MACHINE_KEYSET | CRYPT_NEWKEYSET)) {
+         hProv = 0;
+         return ret;
+      }
+      atexit(s_cleanup_win_csp);
+   }
+   if (CryptGenRandom(hProv, sizeof(*p), (void *)p) == TRUE) {
+      ret = MP_OKAY;
+   }
+   return ret;
+}
+#endif /* WIN32 */
+
+#if !defined(MP_WIN_CSP) && defined(__linux__) && defined(__GLIBC_PREREQ)
+#if __GLIBC_PREREQ(2, 25)
+#define MP_GETRANDOM
+#include <sys/random.h>
+#include <errno.h>
+
+static int s_read_getrandom(mp_digit *p)
+{
+   int ret;
+   do {
+      ret = getrandom(p, sizeof(*p), 0);
+   } while ((ret == -1) && (errno == EINTR));
+   if (ret == sizeof(*p)) return MP_OKAY;
+   return -1;
+}
+#endif
+#endif
+
+/* We assume all platforms besides windows provide "/dev/urandom".
+ * In case yours doesn't, define MP_NO_DEV_URANDOM at compile-time.
+ */
+#if !defined(MP_WIN_CSP) && !defined(MP_NO_DEV_URANDOM)
+#ifndef MP_DEV_URANDOM
+#define MP_DEV_URANDOM "/dev/urandom"
+#endif
+#include <fcntl.h>
+#include <errno.h>
+#include <unistd.h>
+
+static int s_read_dev_urandom(mp_digit *p)
+{
+   ssize_t r;
+   int fd;
+   do {
+      fd = open(MP_DEV_URANDOM, O_RDONLY);
+   } while ((fd == -1) && (errno == EINTR));
+   if (fd == -1) return -1;
+   do {
+      r = read(fd, p, sizeof(*p));
+   } while ((r == -1) && (errno == EINTR));
+   close(fd);
+   if (r != sizeof(*p)) return -1;
+   return MP_OKAY;
+}
+#endif
+
+#if defined(MP_PRNG_ENABLE_LTM_RNG)
+unsigned long (*ltm_rng)(unsigned char *out, unsigned long outlen, void (*callback)(void));
+void (*ltm_rng_callback)(void);
+
+static int s_read_ltm_rng(mp_digit *p)
+{
+   unsigned long ret;
+   if (ltm_rng == NULL) return -1;
+   ret = ltm_rng((void *)p, sizeof(*p), ltm_rng_callback);
+   if (ret != sizeof(*p)) return -1;
+   return MP_OKAY;
+}
+#endif
+
+static int s_rand_digit(mp_digit *p)
+{
+   int ret = -1;
+
+#if defined(MP_ARC4RANDOM)
+   ret = s_read_arc4random(p);
+   if (ret == MP_OKAY) return ret;
+#endif
+
+#if defined(MP_WIN_CSP)
+   ret = s_read_win_csp(p);
+   if (ret == MP_OKAY) return ret;
+#else
+
+#if defined(MP_GETRANDOM)
+   ret = s_read_getrandom(p);
+   if (ret == MP_OKAY) return ret;
+#endif
+#if defined(MP_DEV_URANDOM)
+   ret = s_read_dev_urandom(p);
+   if (ret == MP_OKAY) return ret;
+#endif
+
+#endif /* MP_WIN_CSP */
+
+#if defined(MP_PRNG_ENABLE_LTM_RNG)
+   ret = s_read_ltm_rng(p);
+   if (ret == MP_OKAY) return ret;
+#endif
+
+   return ret;
+}
+
+/* makes a pseudo-random int of a given size */
+int mp_rand_digit(mp_digit *r)
+{
+   int ret = s_rand_digit(r);
+   *r &= MP_MASK;
+   return ret;
 }
 
 int mp_rand(mp_int *a, int digits)
@@ -53,8 +191,10 @@ int mp_rand(mp_int *a, int digits)
 
    /* first place a random non-zero digit */
    do {
-      d = s_gen_random();
+      if (mp_rand_digit(&d) != MP_OKAY) {
-   } while (d == 0);
+         return MP_VAL;
+      }
+   } while (d == 0u);
 
    if ((res = mp_add_d(a, d, a)) != MP_OKAY) {
       return res;
@@ -65,7 +205,10 @@ int mp_rand(mp_int *a, int digits)
          return res;
       }
 
-      if ((res = mp_add_d(a, s_gen_random(), a)) != MP_OKAY) {
+      if (mp_rand_digit(&d) != MP_OKAY) {
+         return MP_VAL;
+      }
+      if ((res = mp_add_d(a, d, a)) != MP_OKAY) {
          return res;
       }
    }

bn_mp_read_radix.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_READ_RADIX_C)
+#ifdef BN_MP_READ_RADIX_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,16 +9,14 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* read a string [ASCII] in a given radix */
 int mp_read_radix(mp_int *a, const char *str, int radix)
 {
    int     y, res, neg;
+   unsigned pos;
    char    ch;
 
    /* zero the digit bignum */
@@ -49,31 +47,30 @@ int mp_read_radix(mp_int *a, const char *str, int radix)
        * [e.g. in hex]
        */
       ch = (radix <= 36) ? (char)toupper((int)*str) : *str;
-      for (y = 0; y < 64; y++) {
+      pos = (unsigned)(ch - '(');
-         if (ch == mp_s_rmap[y]) {
+      if (mp_s_rmap_reverse_sz < pos) {
-            break;
+         break;
-         }
       }
+      y = (int)mp_s_rmap_reverse[pos];
 
       /* if the char was found in the map
        * and is less than the given radix add it
        * to the number, otherwise exit the loop.
        */
-      if (y < radix) {
+      if ((y == 0xff) || (y >= radix)) {
-         if ((res = mp_mul_d(a, (mp_digit)radix, a)) != MP_OKAY) {
-            return res;
-         }
-         if ((res = mp_add_d(a, (mp_digit)y, a)) != MP_OKAY) {
-            return res;
-         }
-      } else {
          break;
       }
+      if ((res = mp_mul_d(a, (mp_digit)radix, a)) != MP_OKAY) {
+         return res;
+      }
+      if ((res = mp_add_d(a, (mp_digit)y, a)) != MP_OKAY) {
+         return res;
+      }
       ++str;
    }
 
    /* if an illegal character was found, fail. */
-   if (!(*str == '\0' || *str == '\r' || *str == '\n')) {
+   if (!((*str == '\0') || (*str == '\r') || (*str == '\n'))) {
       mp_zero(a);
       return MP_VAL;
    }

bn_mp_read_signed_bin.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_READ_SIGNED_BIN_C)
+#ifdef BN_MP_READ_SIGNED_BIN_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* read signed bin, big endian, first byte is 0==positive or 1==negative */
@@ -26,7 +23,7 @@ int mp_read_signed_bin(mp_int *a, const unsigned char *b, int c)
    }
 
    /* first byte is 0 for positive, non-zero for negative */
-   if (b[0] == 0) {
+   if (b[0] == (unsigned char)0) {
       a->sign = MP_ZPOS;
    } else {
       a->sign = MP_NEG;

bn_mp_read_unsigned_bin.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_READ_UNSIGNED_BIN_C)
+#ifdef BN_MP_READ_UNSIGNED_BIN_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* reads a unsigned char array, assumes the msb is stored first [big endian] */
@@ -41,7 +38,7 @@ int mp_read_unsigned_bin(mp_int *a, const unsigned char *b, int c)
       a->used += 1;
 #else
       a->dp[0] = (*b & MP_MASK);
-      a->dp[1] |= ((*b++ >> 7U) & 1);
+      a->dp[1] |= ((*b++ >> 7) & 1u);
       a->used += 2;
 #endif
    }

bn_mp_reduce.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_REDUCE_C)
+#ifdef BN_MP_REDUCE_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* reduces x mod m, assumes 0 < x < m**2, mu is
@@ -33,7 +30,7 @@ int mp_reduce(mp_int *x, const mp_int *m, const mp_int *mu)
    mp_rshd(&q, um - 1);
 
    /* according to HAC this optimization is ok */
-   if (((mp_digit) um) > (((mp_digit)1) << (DIGIT_BIT - 1))) {
+   if ((mp_digit)um > ((mp_digit)1 << (DIGIT_BIT - 1))) {
       if ((res = mp_mul(&q, mu, &q)) != MP_OKAY) {
          goto CLEANUP;
       }
@@ -73,8 +70,8 @@ int mp_reduce(mp_int *x, const mp_int *m, const mp_int *mu)
    }
 
    /* If x < 0, add b**(k+1) to it */
-   if (mp_cmp_d(x, 0) == MP_LT) {
+   if (mp_cmp_d(x, 0uL) == MP_LT) {
-      mp_set(&q, 1);
+      mp_set(&q, 1uL);
       if ((res = mp_lshd(&q, um + 1)) != MP_OKAY)
          goto CLEANUP;
       if ((res = mp_add(x, &q, x)) != MP_OKAY)

bn_mp_reduce_2k.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_REDUCE_2K_C)
+#ifdef BN_MP_REDUCE_2K_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* reduces a modulo n where n is of the form 2**p - d */
@@ -29,29 +26,29 @@ int mp_reduce_2k(mp_int *a, const mp_int *n, mp_digit d)
 top:
    /* q = a/2**p, a = a mod 2**p */
    if ((res = mp_div_2d(a, p, &q, a)) != MP_OKAY) {
-      goto ERR;
+      goto LBL_ERR;
    }
 
-   if (d != 1) {
+   if (d != 1u) {
       /* q = q * d */
       if ((res = mp_mul_d(&q, d, &q)) != MP_OKAY) {
-         goto ERR;
+         goto LBL_ERR;
       }
    }
 
    /* a = a + q */
    if ((res = s_mp_add(a, &q, a)) != MP_OKAY) {
-      goto ERR;
+      goto LBL_ERR;
    }
 
    if (mp_cmp_mag(a, n) != MP_LT) {
       if ((res = s_mp_sub(a, n, a)) != MP_OKAY) {
-         goto ERR;
+         goto LBL_ERR;
       }
       goto top;
    }
 
-ERR:
+LBL_ERR:
    mp_clear(&q);
    return res;
 }

bn_mp_reduce_2k_l.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_REDUCE_2K_L_C)
+#ifdef BN_MP_REDUCE_2K_L_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* reduces a modulo n where n is of the form 2**p - d
@@ -32,27 +29,27 @@ int mp_reduce_2k_l(mp_int *a, const mp_int *n, const mp_int *d)
 top:
    /* q = a/2**p, a = a mod 2**p */
    if ((res = mp_div_2d(a, p, &q, a)) != MP_OKAY) {
-      goto ERR;
+      goto LBL_ERR;
    }
 
    /* q = q * d */
    if ((res = mp_mul(&q, d, &q)) != MP_OKAY) {
-      goto ERR;
+      goto LBL_ERR;
    }
 
    /* a = a + q */
    if ((res = s_mp_add(a, &q, a)) != MP_OKAY) {
-      goto ERR;
+      goto LBL_ERR;
    }
 
    if (mp_cmp_mag(a, n) != MP_LT) {
       if ((res = s_mp_sub(a, n, a)) != MP_OKAY) {
-         goto ERR;
+         goto LBL_ERR;
       }
       goto top;
    }
 
-ERR:
+LBL_ERR:
    mp_clear(&q);
    return res;
 }

bn_mp_reduce_2k_setup.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_REDUCE_2K_SETUP_C)
+#ifdef BN_MP_REDUCE_2K_SETUP_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* determines the setup value */

bn_mp_reduce_2k_setup_l.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_REDUCE_2K_SETUP_L_C)
+#ifdef BN_MP_REDUCE_2K_SETUP_L_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* determines the setup value */
@@ -26,14 +23,14 @@ int mp_reduce_2k_setup_l(const mp_int *a, mp_int *d)
    }
 
    if ((res = mp_2expt(&tmp, mp_count_bits(a))) != MP_OKAY) {
-      goto ERR;
+      goto LBL_ERR;
    }
 
    if ((res = s_mp_sub(&tmp, a, d)) != MP_OKAY) {
-      goto ERR;
+      goto LBL_ERR;
    }
 
-ERR:
+LBL_ERR:
    mp_clear(&tmp);
    return res;
 }

bn_mp_reduce_is_2k.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_REDUCE_IS_2K_C)
+#ifdef BN_MP_REDUCE_IS_2K_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* determines if mp_reduce_2k can be used */
@@ -32,7 +29,7 @@ int mp_reduce_is_2k(const mp_int *a)
 
       /* Test every bit from the second digit up, must be 1 */
       for (ix = DIGIT_BIT; ix < iy; ix++) {
-         if ((a->dp[iw] & iz) == 0) {
+         if ((a->dp[iw] & iz) == 0u) {
             return MP_NO;
          }
          iz <<= 1;

bn_mp_reduce_is_2k_l.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_REDUCE_IS_2K_L_C)
+#ifdef BN_MP_REDUCE_IS_2K_L_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* determines if reduce_2k_l can be used */

bn_mp_reduce_setup.c

@@ -1,5 +1,5 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
-#if defined(ALL_FUNCTIONS) || defined(BN_MP_REDUCE_SETUP_C)
+#ifdef BN_MP_REDUCE_SETUP_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
  * LibTomMath is a library that provides multiple-precision
@@ -9,10 +9,7 @@
  * Michael Fromberger but has been written from scratch with
  * additional optimizations in place.
  *
- * The library is free for all purposes without any express
+ * SPDX-License-Identifier: Unlicense
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
  */
 
 /* pre-calculate the value required for Barrett reduction