diff --git a/src/headers/tomcrypt_math.h b/src/headers/tomcrypt_math.h
index 833deac..6c1ceda 100644
--- a/src/headers/tomcrypt_math.h
+++ b/src/headers/tomcrypt_math.h
@@ -67,7 +67,7 @@ typedef struct {
       @param n    Source upto bits_per_digit (actually meant for very small constants)
       @return CRYPT_OK on success
    */
-   int (*set_int)(void *a, unsigned long n);
+   int (*set_int)(void *a, ltc_mp_digit n);
 
    /** get small constant
       @param a  Small number to read,
@@ -105,7 +105,7 @@ typedef struct {
              LTC_MP_GT if a > b and
              LTC_MP_EQ otherwise.  (signed comparison)
    */
-   int (*compare_d)(void *a, unsigned long n);
+   int (*compare_d)(void *a, ltc_mp_digit n);
 
    /** Count the number of bits used to represent the integer
      @param a   The integer to count
@@ -184,7 +184,7 @@ typedef struct {
      @param c   The destination of "a + b"
      @return CRYPT_OK on success
    */
-   int (*addi)(void *a, unsigned long b, void *c);
+   int (*addi)(void *a, ltc_mp_digit b, void *c);
 
    /** subtract two integers
      @param a   The first source integer
@@ -201,7 +201,7 @@ typedef struct {
      @param c   The destination of "a - b"
      @return CRYPT_OK on success
    */
-   int (*subi)(void *a, unsigned long b, void *c);
+   int (*subi)(void *a, ltc_mp_digit b, void *c);
 
    /** multiply two integers
      @param a   The first source integer
@@ -219,7 +219,7 @@ typedef struct {
      @param c   The destination of "a * b"
      @return CRYPT_OK on success
    */
-   int (*muli)(void *a, unsigned long b, void *c);
+   int (*muli)(void *a, ltc_mp_digit b, void *c);
 
    /** Square an integer
      @param a    The integer to square
@@ -250,7 +250,7 @@ typedef struct {
       @param  c    The destination for the residue
       @return CRYPT_OK on success
    */
-   int (*modi)(void *a, unsigned long b, unsigned long *c);
+   int (*modi)(void *a, ltc_mp_digit b, ltc_mp_digit *c);
 
    /** gcd
       @param  a     The first integer
diff --git a/src/math/gmp_desc.c b/src/math/gmp_desc.c
index 0a23e99..817f08c 100644
--- a/src/math/gmp_desc.c
+++ b/src/math/gmp_desc.c
@@ -61,7 +61,7 @@ static int init_copy(void **a, void *b)
 }
 
 /* ---- trivial ---- */
-static int set_int(void *a, unsigned long b)
+static int set_int(void *a, ltc_mp_digit b)
 {
    LTC_ARGCHK(a != NULL);
    mpz_set_ui(((__mpz_struct *)a), b);
@@ -101,7 +101,7 @@ static int compare(void *a, void *b)
    }
 }
 
-static int compare_d(void *a, unsigned long b)
+static int compare_d(void *a, ltc_mp_digit b)
 {
    int ret;
    LTC_ARGCHK(a != NULL);
@@ -235,7 +235,7 @@ static int add(void *a, void *b, void *c)
    return CRYPT_OK;
 }
 
-static int addi(void *a, unsigned long b, void *c)
+static int addi(void *a, ltc_mp_digit b, void *c)
 {
    LTC_ARGCHK(a != NULL);
    LTC_ARGCHK(c != NULL);
@@ -253,7 +253,7 @@ static int sub(void *a, void *b, void *c)
    return CRYPT_OK;
 }
 
-static int subi(void *a, unsigned long b, void *c)
+static int subi(void *a, ltc_mp_digit b, void *c)
 {
    LTC_ARGCHK(a != NULL);
    LTC_ARGCHK(c != NULL);
@@ -271,7 +271,7 @@ static int mul(void *a, void *b, void *c)
    return CRYPT_OK;
 }
 
-static int muli(void *a, unsigned long b, void *c)
+static int muli(void *a, ltc_mp_digit b, void *c)
 {
    LTC_ARGCHK(a != NULL);
    LTC_ARGCHK(c != NULL);
@@ -317,7 +317,7 @@ static int div_2(void *a, void *b)
 }
 
 /* modi */
-static int modi(void *a, unsigned long b, unsigned long *c)
+static int modi(void *a, ltc_mp_digit b, ltc_mp_digit *c)
 {
    LTC_ARGCHK(a != NULL);
    LTC_ARGCHK(c != NULL);
diff --git a/src/math/ltm_desc.c b/src/math/ltm_desc.c
index 22937e8..ca87d6d 100644
--- a/src/math/ltm_desc.c
+++ b/src/math/ltm_desc.c
@@ -88,7 +88,7 @@ static int init_copy(void **a, void *b)
 }
 
 /* ---- trivial ---- */
-static int set_int(void *a, unsigned long b)
+static int set_int(void *a, ltc_mp_digit b)
 {
    LTC_ARGCHK(a != NULL);
    return mpi_to_ltc_error(mp_set_int(a, b));
@@ -130,7 +130,7 @@ static int compare(void *a, void *b)
    }
 }
 
-static int compare_d(void *a, unsigned long b)
+static int compare_d(void *a, ltc_mp_digit b)
 {
    int ret;
    LTC_ARGCHK(a != NULL);
@@ -212,7 +212,7 @@ static int add(void *a, void *b, void *c)
    return mpi_to_ltc_error(mp_add(a, b, c));
 }
 
-static int addi(void *a, unsigned long b, void *c)
+static int addi(void *a, ltc_mp_digit b, void *c)
 {
    LTC_ARGCHK(a != NULL);
    LTC_ARGCHK(c != NULL);
@@ -228,7 +228,7 @@ static int sub(void *a, void *b, void *c)
    return mpi_to_ltc_error(mp_sub(a, b, c));
 }
 
-static int subi(void *a, unsigned long b, void *c)
+static int subi(void *a, ltc_mp_digit b, void *c)
 {
    LTC_ARGCHK(a != NULL);
    LTC_ARGCHK(c != NULL);
@@ -244,7 +244,7 @@ static int mul(void *a, void *b, void *c)
    return mpi_to_ltc_error(mp_mul(a, b, c));
 }
 
-static int muli(void *a, unsigned long b, void *c)
+static int muli(void *a, ltc_mp_digit b, void *c)
 {
    LTC_ARGCHK(a != NULL);
    LTC_ARGCHK(c != NULL);
@@ -275,7 +275,7 @@ static int div_2(void *a, void *b)
 }
 
 /* modi */
-static int modi(void *a, unsigned long b, unsigned long *c)
+static int modi(void *a, ltc_mp_digit b, ltc_mp_digit *c)
 {
    mp_digit tmp;
    int      err;
diff --git a/src/math/tfm_desc.c b/src/math/tfm_desc.c
index d8e09af..66b4f3e 100644
--- a/src/math/tfm_desc.c
+++ b/src/math/tfm_desc.c
@@ -84,7 +84,7 @@ static int init_copy(void **a, void *b)
 }
 
 /* ---- trivial ---- */
-static int set_int(void *a, unsigned long b)
+static int set_int(void *a, ltc_mp_digit b)
 {
    LTC_ARGCHK(a != NULL);
    fp_set(a, b);
@@ -129,7 +129,7 @@ static int compare(void *a, void *b)
    return 0;
 }
 
-static int compare_d(void *a, unsigned long b)
+static int compare_d(void *a, ltc_mp_digit b)
 {
    int ret;
    LTC_ARGCHK(a != NULL);
@@ -214,7 +214,7 @@ static int add(void *a, void *b, void *c)
    return CRYPT_OK;
 }
 
-static int addi(void *a, unsigned long b, void *c)
+static int addi(void *a, ltc_mp_digit b, void *c)
 {
    LTC_ARGCHK(a != NULL);
    LTC_ARGCHK(c != NULL);
@@ -232,7 +232,7 @@ static int sub(void *a, void *b, void *c)
    return CRYPT_OK;
 }
 
-static int subi(void *a, unsigned long b, void *c)
+static int subi(void *a, ltc_mp_digit b, void *c)
 {
    LTC_ARGCHK(a != NULL);
    LTC_ARGCHK(c != NULL);
@@ -250,7 +250,7 @@ static int mul(void *a, void *b, void *c)
    return CRYPT_OK;
 }
 
-static int muli(void *a, unsigned long b, void *c)
+static int muli(void *a, ltc_mp_digit b, void *c)
 {
    LTC_ARGCHK(a != NULL);
    LTC_ARGCHK(c != NULL);
@@ -284,7 +284,7 @@ static int div_2(void *a, void *b)
 }
 
 /* modi */
-static int modi(void *a, unsigned long b, unsigned long *c)
+static int modi(void *a, ltc_mp_digit b, ltc_mp_digit *c)
 {
    fp_digit tmp;
    int      err;