Remove unnecessary casts in the RSA implementation

src/pk/rsa/rsa_exptmod.c

@@ -53,7 +53,7 @@ int rsa_exptmod(const unsigned char *in,   unsigned long inlen,
 #endif /* LTC_RSA_BLINDING */
                                                            NULL)) != CRYPT_OK)
         { return err; }
-   if ((err = mp_read_unsigned_bin(tmp, (unsigned char *)in, (int)inlen)) != CRYPT_OK)
+   if ((err = mp_read_unsigned_bin(tmp, in, (int)inlen)) != CRYPT_OK)
         { goto error; }
 
 
@@ -130,7 +130,7 @@ int rsa_exptmod(const unsigned char *in,   unsigned long inlen,
       #ifdef LTC_RSA_CRT_HARDENING
       if (has_crt_parameters) {
          if ((err = mp_exptmod(tmp, key->e, key->N, tmpa)) != CRYPT_OK)                              { goto error; }
-         if ((err = mp_read_unsigned_bin(tmpb, (unsigned char *)in, (int)inlen)) != CRYPT_OK)        { goto error; }
+         if ((err = mp_read_unsigned_bin(tmpb, in, (int)inlen)) != CRYPT_OK)                         { goto error; }
          if (mp_cmp(tmpa, tmpb) != LTC_MP_EQ)                                     { err = CRYPT_ERROR; goto error; }
       }
       #endif

src/pk/rsa/rsa_make_key.c

@@ -130,7 +130,7 @@ int rsa_make_key_ubin_e(prng_state *prng, int wprng, int size,
       return err;
    }
 
-   if ((err = mp_read_unsigned_bin(tmp_e, (unsigned char *)e, elen)) == CRYPT_OK)
+   if ((err = mp_read_unsigned_bin(tmp_e, e, elen)) == CRYPT_OK)
      err = rsa_make_key_bn_e(prng, wprng, size, tmp_e, key);
 
    mp_clear(tmp_e);

src/pk/rsa/rsa_set.c

@@ -31,10 +31,10 @@ int rsa_set_key(const unsigned char *N,  unsigned long Nlen,
 
    if ((err = rsa_init(key)) != CRYPT_OK) return err;
 
-   if ((err = mp_read_unsigned_bin(key->N , (unsigned char *)N , Nlen)) != CRYPT_OK)    { goto LBL_ERR; }
-   if ((err = mp_read_unsigned_bin(key->e , (unsigned char *)e , elen)) != CRYPT_OK)    { goto LBL_ERR; }
+   if ((err = mp_read_unsigned_bin(key->N , N , Nlen)) != CRYPT_OK)                     { goto LBL_ERR; }
+   if ((err = mp_read_unsigned_bin(key->e , e , elen)) != CRYPT_OK)                     { goto LBL_ERR; }
    if (d && dlen) {
-      if ((err = mp_read_unsigned_bin(key->d , (unsigned char *)d , dlen)) != CRYPT_OK) { goto LBL_ERR; }
+      if ((err = mp_read_unsigned_bin(key->d , d , dlen)) != CRYPT_OK)                  { goto LBL_ERR; }
       key->type = PK_PRIVATE;
    }
    else {
@@ -72,8 +72,8 @@ int rsa_set_factors(const unsigned char *p,  unsigned long plen,
 
    if (key->type != PK_PRIVATE) return CRYPT_PK_TYPE_MISMATCH;
 
-   if ((err = mp_read_unsigned_bin(key->p , (unsigned char *)p , plen)) != CRYPT_OK) { goto LBL_ERR; }
-   if ((err = mp_read_unsigned_bin(key->q , (unsigned char *)q , qlen)) != CRYPT_OK) { goto LBL_ERR; }
+   if ((err = mp_read_unsigned_bin(key->p , p , plen)) != CRYPT_OK)                  { goto LBL_ERR; }
+   if ((err = mp_read_unsigned_bin(key->q , q , qlen)) != CRYPT_OK)                  { goto LBL_ERR; }
    return CRYPT_OK;
 
 LBL_ERR:
@@ -110,9 +110,9 @@ int rsa_set_crt_params(const unsigned char *dP, unsigned long dPlen,
 
    if (key->type != PK_PRIVATE) return CRYPT_PK_TYPE_MISMATCH;
 
-   if ((err = mp_read_unsigned_bin(key->dP, (unsigned char *)dP, dPlen)) != CRYPT_OK) { goto LBL_ERR; }
-   if ((err = mp_read_unsigned_bin(key->dQ, (unsigned char *)dQ, dQlen)) != CRYPT_OK) { goto LBL_ERR; }
-   if ((err = mp_read_unsigned_bin(key->qP, (unsigned char *)qP, qPlen)) != CRYPT_OK) { goto LBL_ERR; }
+   if ((err = mp_read_unsigned_bin(key->dP, dP, dPlen)) != CRYPT_OK)                  { goto LBL_ERR; }
+   if ((err = mp_read_unsigned_bin(key->dQ, dQ, dQlen)) != CRYPT_OK)                  { goto LBL_ERR; }
+   if ((err = mp_read_unsigned_bin(key->qP, qP, qPlen)) != CRYPT_OK)                  { goto LBL_ERR; }
    return CRYPT_OK;
 
 LBL_ERR:

src/pk/rsa/rsa_sign_hash.c

@@ -78,7 +78,8 @@ int rsa_sign_hash_ex(const unsigned char *in,       unsigned long  inlen,
     }
   } else {
     /* PKCS #1 v1.5 pad the hash */
-    unsigned char *tmpin;
+    unsigned char *tmpin = NULL;
+    const unsigned char *tmpin_ro;
 
     if (padding == LTC_PKCS_1_V1_5) {
       ltc_asn1_list digestinfo[2], siginfo[2];
@@ -111,14 +112,15 @@ int rsa_sign_hash_ex(const unsigned char *in,       unsigned long  inlen,
          XFREE(tmpin);
          return err;
       }
+      tmpin_ro = tmpin;
     } else {
       /* set the pointer and data-length to the input values */
-      tmpin = (unsigned char *)in;
+      tmpin_ro = in;
       y = inlen;
     }
 
     x = *outlen;
-    err = pkcs_1_v1_5_encode(tmpin, y, LTC_PKCS_1_EMSA, modulus_bitlen, NULL, 0, out, &x);
+    err = pkcs_1_v1_5_encode(tmpin_ro, y, LTC_PKCS_1_EMSA, modulus_bitlen, NULL, 0, out, &x);
 
     if (padding == LTC_PKCS_1_V1_5) {
       XFREE(tmpin);