Moving to 2021 edition with code optimizations

Author: Saluki

Cargo.toml

@@ -4,12 +4,13 @@ description = "A minimalistic ARP scan tool"
 license = "AGPL-3.0-or-later"
 version = "0.12.0"
 authors = ["Saluki"]
-edition = "2018"
+edition = "2021"
 readme = "README.md"
 homepage = "https://github.com/Saluki/arp-scan-rs"
 repository = "https://github.com/Saluki/arp-scan-rs"
 keywords = ["arp", "scan", "network", "security"]
 categories = ["command-line-utilities"]
+exclude = ["/.semaphore", "/data", "/release.sh", ".*"]
 
 [dependencies]
 

src/network.rs

@@ -74,7 +74,7 @@ pub fn compute_network_configuration<'a>(interfaces: &'a [NetworkInterface], sca
         Some(name) => String::from(name),
         None => {
 
-            let name = utils::select_default_interface(&interfaces).map(|interface| interface.name);
+            let name = utils::select_default_interface(interfaces).map(|interface| interface.name);
 
             match name {
                 Some(name) => name,
@@ -237,9 +237,14 @@ pub fn send_arp_request(tx: &mut Box<dyn DataLinkSender>, interface: &NetworkInt
         ethernet_packet.set_payload(arp_packet.packet_mut());
     }
 
-    tx.send_to(&ethernet_packet.to_immutable().packet(), Some(interface.clone()));
+    tx.send_to(ethernet_packet.to_immutable().packet(), Some(interface.clone()));
 }
 
+/**
+ * A network iterator for iterating over multiple network ranges in with a
+ * low-memory approach. This iterator was crafted to allow iteration over huge
+ * network ranges (192.168.0.0/16) without consuming excessive memory.
+ */
 pub struct NetworkIterator {
     current_iterator: Option<ipnetwork::IpNetworkIterator>,
     networks: Vec<IpNetwork>,
@@ -268,6 +273,11 @@ impl NetworkIterator {
         }
     }
 
+    /**
+     * The functions below are not public and only used by the Iterator trait
+     * to help keep the next() code clean.
+     */
+
     fn has_no_items_left(&self) -> bool {
         self.current_iterator.is_none() && self.networks.is_empty() && self.random_pool.is_empty()
     }
@@ -391,7 +401,7 @@ pub fn receive_arp_responses(rx: &mut Box<dyn DataLinkReceiver>, options: Arc<Sc
         };
         packet_count += 1;
 
-        let ethernet_packet = match EthernetPacket::new(&arp_buffer[..]) {
+        let ethernet_packet = match EthernetPacket::new(arp_buffer) {
             Some(packet) => packet,
             None => continue
         };

src/utils.rs

@@ -158,13 +158,13 @@ pub fn display_scan_results(response_summary: ResponseSummary, mut target_detail
     for detail in target_details.iter() {
 
         let hostname: &str = match &detail.hostname {
-            Some(hostname) => &hostname,
-            None if !options.resolve_hostname => &"(disabled)",
-            None => &""
+            Some(hostname) => hostname,
+            None if !options.resolve_hostname => "(disabled)",
+            None => ""
         };
         let vendor: &str = match &detail.vendor {
-            Some(vendor) => &vendor,
-            None => &""
+            Some(vendor) => vendor,
+            None => ""
         };
         println!("| {: <15} | {: <18} | {: <h_max$} | {: <v_max$} |", detail.ipv4, detail.mac, hostname, vendor, h_max=hostname_len, v_max=vendor_len);
     }

src/vendor.rs

@@ -61,10 +61,10 @@ impl Vendor {
                         eprintln!("Could not read CSV record ({})", err);
                         process::exit(1);
                     });
-                    let potential_oui = record.get(1).unwrap_or(&"");
+                    let potential_oui = record.get(1).unwrap_or("");
 
                     if vendor_oui.eq(potential_oui) {
-                        return Some(record.get(2).unwrap_or(&"(no vendor)").to_string())
+                        return Some(record.get(2).unwrap_or("(no vendor)").to_string())
                     }
                 }