fix: use closures in consume

config.json

@@ -3,7 +3,7 @@
     "maxmind_key": "",
     "//": "refresh every 24h",
     "refresh_interval": 86400,
-    "path": "/tmp/geofw"
+    "path": "/home/ishan/geofw/geofw"
   },
   "interface": "enp6s18",
   "source_countries": [

geofw/src/main.rs

@@ -9,18 +9,18 @@ use aya::{
 use flate2::bufread::GzDecoder;
 use fxhash::FxHashSet;
 use geofw_common::ProgramParameters;
-use log::{debug, info, warn};
+use log::{debug, error, info, warn};
-use maxmind::ProcessedDb;
+use maxmind::{Data, ProcessedDb};
 use serde_derive::{Deserialize, Serialize};
 use std::{
     fs::File,
-    io::{BufReader, Read},
+    io::{BufReader, ErrorKind, Read},
     path::PathBuf,
 };
 use tar::Archive;
 use tokio::{signal, time};
 
-#[derive(Default, Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 pub struct Config {
     pub db: Db,
     pub interface: String,
@@ -28,42 +28,68 @@ pub struct Config {
     pub source_asn: FxHashSet<u32>,
 }
 
-#[derive(Default, Debug, Clone, PartialEq, Serialize, Deserialize)]
+impl Default for Config {
+    fn default() -> Self {
+        Self {
+            db: Default::default(),
+            interface: "enp1s0".to_string(),
+            source_countries: Default::default(),
+            source_asn: Default::default(),
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 pub struct Db {
     pub maxmind_key: String,
     pub refresh_interval: i64,
     pub path: String,
 }
 
+impl Default for Db {
+    fn default() -> Self {
+        Self {
+            maxmind_key: "".to_string(),
+            refresh_interval: 86400,
+            path: "/tmp/geofw".to_string(),
+        }
+    }
+}
+
 const COUNTRY_DB: &str = "GeoLite2-Country";
 const ASN_DB: &str = "GeoLite2-ASN";
 
 fn read_config(path: &str) -> Result<Config, String> {
-    let mut f = File::open(path).map_err(|e| e.to_string())?;
+    match File::open(path) {
+        Ok(mut f) => {
             let mut contents = vec![];
             f.read_to_end(&mut contents).map_err(|e| e.to_string())?;
-
             serde_json::from_slice(&contents).map_err(|e| e.to_string())
         }
+        Err(e) if e.kind() == ErrorKind::NotFound => {
+            if let Err(e) = File::create(path) {
+                warn!("error in writing config to {}: {}", path, e);
+            }
+            Ok(Default::default())
+        }
+        Err(e) => Err(format!("permission denied reading {}: {}", path, e)),
+    }
+}
 
 fn fetch_geoip_db(config: &Config, db_name: &str) -> Result<ProcessedDb, String> {
     let mut unpack_path = PathBuf::new();
     unpack_path.push(&config.db.path);
     unpack_path.push(format!("{}.mmdb", db_name));
 
-    info!("unpack path = {:?}", unpack_path);
-
     let url = format!("https://download.maxmind.com/app/geoip_download?edition_id={}&license_key={}&suffix=tar.gz", db_name, config.db.maxmind_key);
 
-    info!("fetching db from = {}", url);
+    info!("path = {:?} fetching db from = {}", unpack_path, url);
 
     let response = ureq::get(&url).call();
 
-    let db = match response {
+    match response {
         Ok(v) if v.status() != 200 => {
             warn!("response from maxmind is not 200 = {}", v.status());
-
-            maxmind::MaxmindDB::from_file(&unpack_path.to_string_lossy())?
         }
         Ok(resp) => {
             let reader = resp.into_reader();
@@ -74,40 +100,53 @@ fn fetch_geoip_db(config: &Config, db_name: &str) -> Result<ProcessedDb, String>
                 .entries()
                 .map_err(|e| format!("error in listing files in the archive: {}", e))?;
 
-            let mut db_entry = entries
+            let db_entry = entries
                 .into_iter()
                 .filter_map(|e| e.ok())
                 .filter_map(|entry| {
-                    let path = match entry.path() {
+                    let Ok(path) = entry.path() else {
-                        Ok(v) => v,
+                        return None;
-                        Err(_) => return None,
                     };
-
                     if path.extension().is_none_or(|x| x != "mmdb") {
                         return None;
                     }
                     Some(entry)
                 })
-                .next()
+                .next();
-                .unwrap();
+
+            let Some(mut db_entry) = db_entry else {
+                return Err("error in finding mmdb file in the tarball".to_string());
+            };
 
             db_entry.unpack(&unpack_path).map_err(|e| e.to_string())?;
-
-            maxmind::MaxmindDB::from_file(&unpack_path.to_string_lossy())?
         }
-
         Err(e) => {
             warn!("error in fetching db from maxmind: {}", e);
-
-            maxmind::MaxmindDB::from_file(&unpack_path.to_string_lossy())?
         }
     };
 
+    let db = maxmind::MaxmindDB::from_file(&unpack_path.to_string_lossy())?;
+
     info!("downloaded {}", db_name);
 
     match db_name {
-        COUNTRY_DB => Ok(db.consume_country_database(&config.source_countries)),
+        COUNTRY_DB => Ok(db.consume(|data| -> bool {
-        ASN_DB => Ok(db.consume_asn_database(&config.source_asn)),
+            let Some(Data::Map(country)) = data.get("country".as_bytes()) else {
+                return false;
+            };
+            let Some(iso_code) = country.get("iso_code".as_bytes()) else {
+                return false;
+            };
+
+            config.source_countries.contains(&iso_code.to_string())
+        })),
+        ASN_DB => Ok(db.consume(|data| -> bool {
+            let Some(Data::U32(asn)) = data.get("autonomous_system_number".as_bytes()) else {
+                return false;
+            };
+
+            config.source_asn.contains(asn)
+        })),
 
         _ => Err("unknown db".to_string()),
     }

geofw/src/maxmind.rs

@@ -51,7 +51,7 @@ impl Display for Data<'_> {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
         match self {
             Data::String(s) => f.write_str(&String::from_utf8_lossy(s)),
-            Data::Double(s) => f.write_str(&s.to_string()),
+            Data::Double(s) => write!(f, "{s}"),
             Data::Bytes(s) => f.write_fmt(format_args!("{:?}", s)),
             Data::U16(s) => f.write_str(&s.to_string()),
             Data::U32(s) => f.write_str(&s.to_string()),
@@ -168,6 +168,7 @@ impl MaxmindDB {
         }
     }
 
+    #[allow(unused)]
     pub fn lookup(&self, addr: IpAddr) -> Option<Data> {
         let node_size = self.metadata.record_size as usize * 2 / 8;
         let mut node = 0;
@@ -197,7 +198,7 @@ impl MaxmindDB {
         }
     }
 
-    pub fn consume_country_database(mut self, countries: &FxHashSet<String>) -> ProcessedDb {
+    pub fn consume(mut self, should_block: impl Fn(FxHashMap<&[u8], Data>) -> bool) -> ProcessedDb {
         let mut stack = vec![];
         let node_size = self.metadata.record_size as usize * 2 / 8;
         stack.push((0, 0));
@@ -230,71 +231,8 @@ impl MaxmindDB {
             let Data::Map(data) = data else {
                 unreachable!()
             };
-            let Some(Data::Map(country)) = data.get("country".as_bytes()) else {
-                continue;
-            };
-            let Some(iso_code) = country.get("iso_code".as_bytes()) else {
-                unreachable!()
-            };
 
-            if countries.contains(&iso_code.to_string()) {
+            if should_block(data) {
-                // Mark this node as non existent
-                Self::write_over_node_bytes(
-                    &mut self.data
-                        [node as usize * node_size..(node as usize * node_size) + node_size],
-                    0,
-                    self.metadata.record_size,
-                    BLOCK_MARKER,
-                );
-            }
-        }
-
-        // Trim database to only contain the binary tree
-        ProcessedDb {
-            node_count: self.metadata.node_count,
-            record_size: self.metadata.record_size,
-            db: self.data[..self.metadata.data_section_start].to_vec(),
-        }
-    }
-
-    pub fn consume_asn_database(mut self, asns: &FxHashSet<u32>) -> ProcessedDb {
-        let mut stack = vec![];
-        let node_size = self.metadata.record_size as usize * 2 / 8;
-        stack.push((0, 0));
-
-        while let Some((node, position)) = stack.pop() {
-            let n =
-                &mut self.data[node as usize * node_size..(node as usize * node_size) + node_size];
-            let node_1 = Self::node_from_bytes(n, 0, self.metadata.record_size);
-            let node_2 = Self::node_from_bytes(n, 1, self.metadata.record_size);
-
-            if position < 128 && node_1 < self.metadata.node_count {
-                stack.push((node_1, position + 1));
-            }
-            if position < 128 && node_2 < self.metadata.node_count {
-                stack.push((node_2, position + 1));
-            }
-
-            let data_section_offset = if node_1 != BLOCK_MARKER && node_1 > self.metadata.node_count
-            {
-                node_1 - self.metadata.node_count
-            } else if node_2 != BLOCK_MARKER && node_2 > self.metadata.node_count {
-                node_2 - self.metadata.node_count
-            } else {
-                continue;
-            };
-
-            let (data, _) = self
-                .read_data(self.metadata.data_section_start + data_section_offset as usize - 16);
-
-            let Data::Map(data) = data else {
-                unreachable!()
-            };
-            let Some(Data::U32(asn)) = data.get("autonomous_system_number".as_bytes()) else {
-                continue;
-            };
-
-            if asns.contains(asn) {
                 // Mark this node as non existent
                 Self::write_over_node_bytes(
                     &mut self.data