Fixed calculation of brain-attack if a given wordlist has the size zero

Fixes https://github.com/hashcat/hashcat/issues/1756

docs/changes.txt

@@ -27,6 +27,7 @@
 ## Bugs
 ##
 
+- Fixed calculation of brain-attack if a given wordlist has the size zero
 - Fixed automated calculation of brain-session when not using all hashes in the hashlist
 - Fixed endianness and invalid separator character in outfile format for hash-mode 16801 (WPA-PMKID-PMK)
 - Fixed ignoring --brain-client-features configuration when brain-server has attack positions information from a previous run

src/brain.c

@@ -536,15 +536,11 @@ u64 brain_compute_attack_wordlist (const char *filename)
 
   FILE *fd = fopen (filename, "rb");
 
-  size_t nread = fread (buf, sizeof (u8), FBUFSZ, fd);
-
-  XXH64_update (state, buf, nread);
-
-  while (nread <= 0)
+  while (!feof (fd))
   {
-    XXH64_update (state, buf, nread);
+    const size_t nread = fread (buf, 1, FBUFSZ, fd);
 
-    nread = fread (buf, sizeof (u8), FBUFSZ, fd);
+    XXH64_update (state, buf, nread);
   }
 
   fclose (fd);

src/hashcat.c

@@ -164,7 +164,10 @@ static int inner2_loop (hashcat_ctx_t *hashcat_ctx)
   }
 
   #ifdef WITH_BRAIN
-  user_options->brain_attack = brain_compute_attack (hashcat_ctx);
+  if (user_options->brain_client == true)
+  {
+    user_options->brain_attack = brain_compute_attack (hashcat_ctx);
+  }
   #endif
 
   /**