config: Enable passing a hostname instead of IP

For the options 'ip', 'contact_ip', and 'registrar_ip', allow a hostname
to be used instead of an IP address.

Fixes #848

Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>

keylime-agent/src/config.rs

@@ -565,8 +565,24 @@ fn config_translate_keywords(
         s => s.to_string(),
     };
 
-    let ip = parse_ip(config.agent.ip.as_ref())?.to_string();
-    let contact_ip = parse_ip(config.agent.contact_ip.as_ref())?.to_string();
+    debug!("Will parse IP");
+
+    let ip = match parse_ip(config.agent.ip.as_ref()) {
+        Ok(ip) => ip.to_string(),
+        Err(_) => {
+            debug!("Will parse hostname");
+
+            parse_hostname(config.agent.ip.as_ref())?.to_string()
+        }
+    };
+
+    let contact_ip = match parse_ip(config.agent.contact_ip.as_ref()) {
+        Ok(ip) => ip.to_string(),
+        Err(_) => {
+            parse_hostname(config.agent.contact_ip.as_ref())?.to_string()
+        }
+    };
+
     let registrar_ip = match parse_ip(config.agent.registrar_ip.as_ref()) {
         Ok(ip) => ip.to_string(),
         Err(_) => {
@@ -711,6 +727,30 @@ mod tests {
         assert_eq!(expected, default);
     }
 
+    #[test]
+    fn test_hostname_support() {
+        let default = AgentConfig::default();
+
+        let modified = AgentConfig {
+            ip: "localhost".to_string(),
+            contact_ip: "contact.ip".to_string(),
+            registrar_ip: "registrar.ip".to_string(),
+            ..default
+        };
+
+        let c = KeylimeConfig { agent: modified };
+
+        let result = config_translate_keywords(&c);
+        assert!(result.is_ok());
+        let result = result.unwrap(); //#[allow_ci]
+        let resulting_ip = result.agent.ip;
+        let resulting_contact_ip = result.agent.contact_ip;
+        let resulting_registrar_ip = result.agent.registrar_ip;
+        assert_eq!(resulting_ip, "localhost");
+        assert_eq!(resulting_contact_ip, "contact.ip");
+        assert_eq!(resulting_registrar_ip, "registrar.ip");
+    }
+
     #[test]
     fn get_revocation_cert_path_default() {
         let test_config = KeylimeConfig::default();

keylime-agent/src/main.rs

@@ -968,12 +968,22 @@ async fn main() -> Result<()> {
 
     let server;
 
-    // Add bracket if IPv6
-    let ip = if config.agent.ip.parse::<IpAddr>()?.is_ipv6() {
-        format!("[{}]", config.agent.ip)
-    } else {
-        config.agent.ip.to_string()
+    // Try to parse as an IP address
+    let ip = match config.agent.ip.parse::<IpAddr>() {
+        Ok(ip_addr) => {
+            // Add bracket if IPv6, otherwise use as it is
+            if ip_addr.is_ipv6() {
+                format!("[{}]", ip_addr)
+            } else {
+                ip_addr.to_string()
+            }
+        }
+        Err(_) => {
+            // If the address was not an IP address, treat as a hostname
+            config.agent.ip.to_string()
+        }
     };
+
     let port = config.agent.port;
     if config.agent.enable_agent_mtls && ssl_context.is_some() {
         server = actix_server