Remove unnecessary casts in the DSA implementation

src/pk/dsa/dsa_set.c

@@ -30,9 +30,9 @@ int dsa_set_pqg(const unsigned char *p,  unsigned long plen,
    /* init key */
    if ((err = dsa_int_init(key)) != CRYPT_OK) return err;
 
-   if ((err = mp_read_unsigned_bin(key->p, (unsigned char *)p , plen)) != CRYPT_OK) { goto LBL_ERR; }
-   if ((err = mp_read_unsigned_bin(key->g, (unsigned char *)g , glen)) != 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->g, g , glen)) != CRYPT_OK)                  { goto LBL_ERR; }
+   if ((err = mp_read_unsigned_bin(key->q, q , qlen)) != CRYPT_OK)                  { goto LBL_ERR; }
 
    key->qord = mp_unsigned_bin_size(key->q);
 
@@ -75,12 +75,12 @@ int dsa_set_key(const unsigned char *in, unsigned long inlen, int type, dsa_key
 
    if (type == PK_PRIVATE) {
       key->type = PK_PRIVATE;
-      if ((err = mp_read_unsigned_bin(key->x, (unsigned char *)in, inlen)) != CRYPT_OK) { goto LBL_ERR; }
+      if ((err = mp_read_unsigned_bin(key->x, in, inlen)) != CRYPT_OK)                  { goto LBL_ERR; }
       if ((err = mp_exptmod(key->g, key->x, key->p, key->y)) != CRYPT_OK)               { goto LBL_ERR; }
    }
    else {
       key->type = PK_PUBLIC;
-      if ((err = mp_read_unsigned_bin(key->y, (unsigned char *)in, inlen)) != CRYPT_OK) { goto LBL_ERR; }
+      if ((err = mp_read_unsigned_bin(key->y, in, inlen)) != CRYPT_OK)                  { goto LBL_ERR; }
    }
 
    if ((err = dsa_int_validate_xy(key, &stat)) != CRYPT_OK)                             { goto LBL_ERR; }

src/pk/dsa/dsa_sign_hash.c

@@ -80,7 +80,7 @@ retry:
    inlen = MIN(inlen, (unsigned long)(key->qord));
 
    /* now find s = (in + xr)/k mod q */
-   if ((err = mp_read_unsigned_bin(tmp, (unsigned char *)in, inlen)) != CRYPT_OK)      { goto error; }
+   if ((err = mp_read_unsigned_bin(tmp, in, inlen)) != CRYPT_OK)                       { goto error; }
    if ((err = mp_mul(key->x, r, s)) != CRYPT_OK)                                       { goto error; }
    if ((err = mp_add(s, tmp, s)) != CRYPT_OK)                                          { goto error; }
    if ((err = mp_mulmod(s, kinv, key->q, s)) != CRYPT_OK)                              { goto error; }

src/pk/dsa/dsa_verify_hash.c

@@ -53,7 +53,7 @@ int dsa_verify_hash_raw(         void   *r,          void   *s,
    if ((err = mp_invmod(s, key->q, w)) != CRYPT_OK)                                       { goto error; }
 
    /* u1 = m * w mod q */
-   if ((err = mp_read_unsigned_bin(u1, (unsigned char *)hash, hashlen)) != CRYPT_OK)      { goto error; }
+   if ((err = mp_read_unsigned_bin(u1, hash, hashlen)) != CRYPT_OK)                       { goto error; }
    if ((err = mp_mulmod(u1, w, key->q, u1)) != CRYPT_OK)                                  { goto error; }
 
    /* u2 = r*w mod q */