read DNS ip address from openvpn output ( fix #3 )

Cargo.toml

@@ -21,6 +21,7 @@ documentation = "https://docs.rs/openaws-vpn-client/"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+regex= "1"
 gtk = "=0.14.3"
 lazy_static = "=1.4.0"
 tokio = { version = "=1.14.0", features = ["full"] }

src/cmd.rs

@@ -165,6 +165,11 @@ pub async fn connect_ovpn(
         if let Ok(ref line) = next {
             if let Some(line) = line {
                 log.append_process(pid, line.as_str());
+                tokio::spawn(async move {
+                    // Process each socket concurrently.
+                    parse_dns(line.to_string())
+                        .and_then(|dns_address| _WIP_("Do something with this IP address"))
+                });
             } else {
                 break;
             }

src/dns.rs

@@ -4,6 +4,7 @@ use domain::base::iana::Class;
 use domain::base::{Dname, Rtype};
 use domain::rdata::A;
 use rand::prelude::*;
+use regex::Regex;
 use std::net::IpAddr;
 use std::ops::Deref;
 use std::rc::Rc;
@@ -78,3 +79,23 @@ fn rng_domain() -> String {
     rng.fill_bytes(&mut bts);
     hex::encode(bts)
 }
+
+/// parse DNS from openvpn log written to stdout
+pub fn parse_dns(line: String) -> Option<String> {
+    let header = &line.as_bytes()[..32];
+    // expect a header for this line
+    if std::str::from_utf8(header).unwrap() != "PUSH: Received control message: ".to_string() {
+        println!(
+            "no son iguales «{}» & »{}«",
+            std::str::from_utf8(header).unwrap(),
+            "PUSH: Received control message:"
+        );
+        return None;
+    }
+    let dhcp_option_dns_re = Regex::new(r"dhcp-option DNS ([^,]+),").unwrap();
+    for ip in dhcp_option_dns_re.captures_iter(&line) {
+        return Some((&ip[1]).to_string());
+    }
+    None
+}
+