Merge PR #9: dynamic Google IP discovery + frontend validation

Thanks @v4g4b0nd-0x76 for the feature. Two small fixes folded in on
the merge so master still builds + doesn't hit sharp edges:

- src/scan_ips.rs: rand::thread_rng() held across an .await tripped
  the Send bound on the async fn (ThreadRng isn't Send). Scoped the
  rng in a block so it drops before subsequent awaits.
- src/scan_ips.rs: guard /0 and /32 CIDRs in cidr_to_ips and
  ip_in_cidr against the 1u32 << 32 shift panic (debug mode). goog.json
  is unlikely to contain either but defensive.

Behavior unchanged otherwise:
- fetch_ips_from_api=false (default): identical to previous static
  scan-ips behavior.
- fetch_ips_from_api=true: fetches goog.json from www.gstatic.com,
  resolves famous Google domain IPs, prioritises matching CIDRs,
  samples up to max_ips_to_scan candidates, validates with gws/
  x-google-/alt-svc headers. If the fetch fails, falls back to the
  static list cleanly — verified locally.

Closes #10.

README.md

@@ -174,6 +174,32 @@ Then:
 
 `script_id` can also be a JSON array: `["id1", "id2", "id3"]`.
 
+#### scan-ips configuration (optional)
+
+By default, the scan-ips subcommand uses a static array of IPs.
+
+You can enable dynamic IP discovery by setting fetch_ips_from_api to true in config.json:
+
+```json
+{
+  "fetch_ips_from_api": true,
+  "max_ips_to_scan": 100,
+  "scan_batch_size":100,
+  "google_ip_validation": true // check whether ips belongs to frontend sites of google or not
+}
+```
+
+When enabled:
+
+- Fetches goog.json from Google’s public IP ranges API
+- Extracts all CIDRs and expands them to individual IPs
+- Prioritizes IPs from famous Google domains (google.com, youtube.com, etc.)
+- Randomly selects up to max_ips_to_scan candidates (prioritized IPs first)
+- Tests only the selected candidates for connectivity and frontend validation.
+
+By using this options you may find ips witch are faster than static array that is provided as default but there is no guarantee that this ips would work.
+
+
 ### Step 5 — Point your client at the proxy
 
 The tool listens on **two** ports. Use whichever your client supports:
@@ -423,6 +449,32 @@ Original project: <https://github.com/masterking32/MasterHttpRelayVPN> by [@mast
 
 **فایرفاکس (ساده‌ترین):**
 
+
+#### پیکربندی scan-ips (اختیاری)
+به‌طور پیش‌فرض، دستور scan-ips از آرایه‌ای ثابت از IPها استفاده می‌کند.
+
+می‌توانید کشف پویای IP را با تنظیم fetch_ips_from_api روی true در config.json فعال کنید:
+
+```json
+{
+  "fetch_ips_from_api": true,
+  "max_ips_to_scan": 100,
+  "scan_batch_size":100,
+  "google_ip_validation": true // برسی هدر های بازگشته از ایپی برای برسی هدر ها و تشخیص کاربردی بودن ایپی
+}
+```
+
+زمانی که فعال باشد:
+
+- فایل goog.json را از API محدوده‌های عمومی IP گوگل دریافت می‌کند
+تمام CIDRها را استخراج کرده و به IPهای جداگانه تبدیل می‌کند
+- به IPهای دامنه‌های معروف گوگل (google.com، youtube.com و غیره) اولویت می‌دهد
+به‌صورت تصادفی تا max_ips_to_scan کاندید انتخاب می‌کند (ابتدا IPهای اولویت‌دار)
+فقط کاندیدهای انتخاب‌شده را برای اتصال و اعتبارسنجی frontend تست می‌کند.
+
+با استفاده از این گزینه‌ها ممکن است IPهایی پیدا کنید که سریع‌تر از آرایه ثابت پیش‌فرض هستند اما تضمینی وجود ندارد که این IPها کار کنند.
+
+#### ۵. تنظیم proxy در کلاینت
 ۱. منوی `Settings` را باز کنید، در خانهٔ جست‌وجو عبارت `proxy` را تایپ کنید
 ۲. روی **`Network Settings`** کلیک کنید
 ۳. گزینهٔ **`Manual proxy configuration`** را انتخاب کنید

src/bin/ui.rs

@@ -137,6 +137,10 @@ struct FormState {
     sni_custom_input: String,
     /// Whether the floating SNI editor window is open.
     sni_editor_open: bool,
+    fetch_ips_from_api: bool,
+    max_ips_to_scan: usize,
+    scan_batch_size:usize,
+    google_ip_validation: bool
 }
 
 #[derive(Clone, Debug)]
@@ -182,6 +186,10 @@ fn load_form() -> FormState {
             sni_pool,
             sni_custom_input: String::new(),
             sni_editor_open: false,
+            fetch_ips_from_api:c.fetch_ips_from_api,
+            max_ips_to_scan:c.max_ips_to_scan,
+            google_ip_validation: c.google_ip_validation,
+            scan_batch_size:c.scan_batch_size
         }
     } else {
         FormState {
@@ -200,6 +208,10 @@ fn load_form() -> FormState {
             sni_pool: sni_pool_for_form(None, "www.google.com"),
             sni_custom_input: String::new(),
             sni_editor_open: false,
+            fetch_ips_from_api:false,
+            max_ips_to_scan:100,
+            google_ip_validation:true,
+            scan_batch_size:500
         }
     }
 }
@@ -321,6 +333,10 @@ impl FormState {
                     Some(active)
                 }
             },
+            fetch_ips_from_api:self.fetch_ips_from_api,
+            max_ips_to_scan: self.max_ips_to_scan,
+            google_ip_validation:self.google_ip_validation,
+            scan_batch_size:self.scan_batch_size
         })
     }
 }

src/config.rs

@@ -80,8 +80,24 @@ pub struct Config {
     /// various times). Can be tested per-name via the UI or `mhrv-rs test-sni`.
     #[serde(default)]
     pub sni_hosts: Option<Vec<String>>,
+    #[serde(default = "default_fetch_ips_from_api")]
+    pub fetch_ips_from_api: bool,
+
+    #[serde(default = "default_max_ips_to_scan")]
+    pub max_ips_to_scan: usize,
+
+    #[serde(default = "default_scan_batch_size")]
+    pub scan_batch_size:usize,
+
+    #[serde(default = "default_google_ip_validation")]
+    pub google_ip_validation: bool
 }
 
+fn default_fetch_ips_from_api() -> bool { false }
+fn default_max_ips_to_scan() -> usize { 100 }
+fn default_scan_batch_size() -> usize {500}
+fn default_google_ip_validation() -> bool {true}
+
 fn default_google_ip() -> String {
     "216.239.38.120".into()
 }

src/scan_ips.rs

@@ -2,6 +2,7 @@ use std::net::SocketAddr;
 use std::sync::Arc;
 use std::time::{Duration, Instant};
 
+use rand::seq::SliceRandom;
 use tokio::io::{AsyncReadExt, AsyncWriteExt};
 use tokio::net::TcpStream;
 use tokio_rustls::rustls::client::danger::{
@@ -44,6 +45,17 @@ const CANDIDATE_IPS: &[&str] = &[
     "142.250.72.110",
 ];
 
+const FAMOUS_GOOGLE_DOMAINS: &[&str] = &[
+    "google.com",
+    "www.google.com",
+    "youtube.com",
+    "www.youtube.com",
+    "gmail.com",
+    "drive.google.com",
+    "docs.google.com",
+    "maps.google.com",
+];
+
 const PROBE_TIMEOUT: Duration = Duration::from_secs(4);
 const CONCURRENCY: usize = 8;
 
@@ -54,8 +66,15 @@ struct Result_ {
 }
 
 pub async fn run(config: &Config) -> bool {
+    let ips = fetch_google_ips(config).await;
+    let google_ip_validation = config.google_ip_validation;
     let sni = config.front_domain.clone();
-    println!("Scanning {} Google frontend IPs (SNI={}, timeout={}s)...", CANDIDATE_IPS.len(), sni, PROBE_TIMEOUT.as_secs());
+    println!(
+        "Scanning {} Google frontend IPs (SNI={}, timeout={}s)...",
+        ips.len(),
+        sni,
+        PROBE_TIMEOUT.as_secs()
+    );
     println!();
 
     let tls_cfg = ClientConfig::builder()
@@ -65,15 +84,15 @@ pub async fn run(config: &Config) -> bool {
     let connector = TlsConnector::from(Arc::new(tls_cfg));
 
     let sem = Arc::new(tokio::sync::Semaphore::new(CONCURRENCY));
-    let mut tasks = Vec::with_capacity(CANDIDATE_IPS.len());
-    for ip in CANDIDATE_IPS {
+    let mut tasks = Vec::with_capacity(ips.len());
+    for ip in &ips {
         let sni = sni.clone();
         let connector = connector.clone();
         let sem = sem.clone();
         let ip = ip.to_string();
         tasks.push(tokio::spawn(async move {
-            let _permit = sem.acquire().await.ok();
-            probe(&ip, &sni, connector).await
+            let _permit: Option<tokio::sync::SemaphorePermit<'_>> = sem.acquire().await.ok();
+            probe(&ip, &sni, connector,google_ip_validation).await
         }));
     }
 
@@ -115,7 +134,405 @@ pub async fn run(config: &Config) -> bool {
     }
 }
 
-async fn probe(ip: &str, sni: &str, connector: TlsConnector) -> Result_ {
+async fn fetch_google_ips(config: &Config) -> Vec<String> {
+    if !config.fetch_ips_from_api {
+        tracing::info!("fetch_ips_from_api disabled, using static fallback");
+        return CANDIDATE_IPS.iter().map(|s| s.to_string()).collect();
+    }
+
+    match fetch_and_validate_google_ips(
+        &config.front_domain,
+        config.max_ips_to_scan,
+        config.scan_batch_size,
+        config.google_ip_validation
+    )
+    .await
+    {
+        Ok(ips) if !ips.is_empty() => {
+            tracing::info!("✓ Validated {} working IPs from goog.json", ips.len());
+            ips
+        }
+        Ok(_) => {
+            tracing::warn!("No working IPs found in goog.json, using static fallback");
+            CANDIDATE_IPS.iter().map(|s| s.to_string()).collect()
+        }
+        Err(e) => {
+            tracing::warn!(
+                "Failed to fetch/validate Google IPs: {}, using static fallback",
+                e
+            );
+            CANDIDATE_IPS.iter().map(|s| s.to_string()).collect()
+        }
+    }
+}
+
+async fn fetch_and_validate_google_ips(
+    sni: &str,
+    max_ips: usize,
+    batch_size: usize,
+     google_ip_validation: bool
+) -> Result<Vec<String>, Box<dyn std::error::Error>> {
+    let famous_ips = resolve_famous_domains().await;
+    tracing::info!(
+        "Resolved {} IPs from famous Google domains",
+        famous_ips.len()
+    );
+
+    let cidrs = fetch_google_cidrs().await?;
+    tracing::info!("Fetched {} CIDR blocks from goog.json", cidrs.len());
+
+    let priority_cidrs = find_matching_cidrs(&famous_ips, &cidrs);
+    tracing::info!("Found {} CIDRs containing famous IPs", priority_cidrs.len());
+
+    let mut priority_ips = Vec::new();
+    for cidr in &priority_cidrs {
+        priority_ips.extend(cidr_to_ips(cidr));
+    }
+
+    let mut other_ips = Vec::new();
+    for cidr in &cidrs {
+        if !priority_cidrs.contains(cidr) {
+            other_ips.extend(cidr_to_ips(cidr));
+        }
+    }
+
+    tracing::info!(
+        "Extracted {} priority IPs and {} other IPs",
+        priority_ips.len(),
+        other_ips.len()
+    );
+
+    let priority_ips_len = priority_ips.len();
+    let other_ips_len = other_ips.len();
+
+    // Scope the rng so it's dropped before any subsequent `.await` — rand's
+    // ThreadRng isn't Send, so holding it across an await would error out
+    // the whole async fn's Send bound.
+    {
+        let mut rng = rand::thread_rng();
+        priority_ips.shuffle(&mut rng);
+        other_ips.shuffle(&mut rng);
+    }
+
+    let mut candidate_ips = Vec::new();
+    candidate_ips.extend(priority_ips.into_iter().take(max_ips));
+    if candidate_ips.len() < max_ips {
+        let remaining = max_ips - candidate_ips.len();
+        candidate_ips.extend(other_ips.into_iter().take(remaining));
+    }
+
+    if candidate_ips.is_empty() {
+        return Err("No valid IPs extracted from CIDRs".into());
+    }
+
+    tracing::info!(
+        "Selected {} IPs to test (from {} total), testing in batches...",
+        candidate_ips.len(),
+        priority_ips_len + other_ips_len
+    );
+
+    let mut working_ips = Vec::new();
+
+    for (i, chunk) in candidate_ips.chunks(batch_size).enumerate() {
+        tracing::debug!("Testing batch {} ({} IPs)...", i + 1, chunk.len());
+        let batch_working = validate_ips(chunk, sni,google_ip_validation).await;
+        working_ips.extend(batch_working);
+    }
+
+    tracing::info!(
+        "Found {} working IPs from {} tested",
+        working_ips.len(),
+        candidate_ips.len()
+    );
+
+    Ok(working_ips)
+}
+
+async fn resolve_famous_domains() -> Vec<String> {
+    let mut ips = Vec::new();
+    for domain in FAMOUS_GOOGLE_DOMAINS {
+        match tokio::net::lookup_host(format!("{}:443", domain)).await {
+            Ok(addrs) => {
+                for addr in addrs {
+                    if let SocketAddr::V4(v4) = addr {
+                        ips.push(v4.ip().to_string());
+                    }
+                }
+            }
+            Err(e) => {
+                tracing::debug!("Failed to resolve {}: {}", domain, e);
+            }
+        }
+    }
+    ips.sort();
+    ips.dedup();
+    ips
+}
+
+fn find_matching_cidrs(ips: &[String], cidrs: &[String]) -> Vec<String> {
+    let mut matches = Vec::new();
+    for cidr in cidrs {
+        for ip in ips {
+            if ip_in_cidr(ip, cidr) {
+                matches.push(cidr.clone());
+                break;
+            }
+        }
+    }
+    matches
+}
+
+fn ip_in_cidr(ip: &str, cidr: &str) -> bool {
+    let parts: Vec<&str> = cidr.split('/').collect();
+    if parts.len() != 2 {
+        return false;
+    }
+
+    let base_ip = parts[0];
+    let prefix_len: u8 = match parts[1].parse() {
+        Ok(p) => p,
+        Err(_) => return false,
+    };
+
+    let ip_num = match ip_to_u32(ip) {
+        Some(n) => n,
+        None => return false,
+    };
+
+    let base_num = match ip_to_u32(base_ip) {
+        Some(n) => n,
+        None => return false,
+    };
+
+    // Mask defends against /0 (shift-32 of u32 would panic in debug).
+    let mask: u32 = if prefix_len == 0 {
+        0
+    } else if prefix_len >= 32 {
+        u32::MAX
+    } else {
+        !((1u32 << (32 - prefix_len)) - 1)
+    };
+    (ip_num & mask) == (base_num & mask)
+}
+
+fn ip_to_u32(ip: &str) -> Option<u32> {
+    let octets: Vec<&str> = ip.split('.').collect();
+    if octets.len() != 4 {
+        return None;
+    }
+
+    let o: Vec<u8> = octets.iter().filter_map(|s| s.parse().ok()).collect();
+    if o.len() != 4 {
+        return None;
+    }
+
+    Some(((o[0] as u32) << 24) | ((o[1] as u32) << 16) | ((o[2] as u32) << 8) | (o[3] as u32))
+}
+
+async fn fetch_google_cidrs() -> Result<Vec<String>, Box<dyn std::error::Error>> {
+    let stream = tokio::time::timeout(
+        Duration::from_secs(10),
+        TcpStream::connect("www.gstatic.com:443"),
+    )
+    .await??;
+
+    let tls_cfg = ClientConfig::builder()
+        .dangerous()
+        .with_custom_certificate_verifier(Arc::new(NoVerify))
+        .with_no_client_auth();
+    let connector = TlsConnector::from(Arc::new(tls_cfg));
+    let server_name = ServerName::try_from("www.gstatic.com".to_string())?;
+
+    let mut tls_stream = tokio::time::timeout(
+        Duration::from_secs(10),
+        connector.connect(server_name, stream),
+    )
+    .await??;
+
+    let request = "GET /ipranges/goog.json HTTP/1.1\r\n\
+                   Host: www.gstatic.com\r\n\
+                   Connection: close\r\n\
+                   \r\n";
+    tls_stream.write_all(request.as_bytes()).await?;
+    tls_stream.flush().await?;
+
+    let mut response = Vec::new();
+    tokio::time::timeout(Duration::from_secs(15), async {
+        let mut buf = [0u8; 4096];
+        loop {
+            match tls_stream.read(&mut buf).await {
+                Ok(0) => break,
+                Ok(n) => response.extend_from_slice(&buf[..n]),
+                Err(_) => break,
+            }
+        }
+    })
+    .await?;
+
+    let response_str = String::from_utf8_lossy(&response);
+    let body = response_str
+        .split("\r\n\r\n")
+        .nth(1)
+        .ok_or("No HTTP body found")?;
+
+    let json: serde_json::Value = serde_json::from_str(body)?;
+    let prefixes = json["prefixes"].as_array().ok_or("No prefixes array")?;
+
+    let mut cidrs = Vec::new();
+    for prefix in prefixes {
+        if let Some(ipv4) = prefix["ipv4Prefix"].as_str() {
+            cidrs.push(ipv4.to_string());
+        }
+    }
+
+    Ok(cidrs)
+}
+
+fn cidr_to_ips(cidr: &str) -> Vec<String> {
+    let parts: Vec<&str> = cidr.split('/').collect();
+    if parts.len() != 2 {
+        return Vec::new();
+    }
+
+    let base_ip = parts[0];
+    let prefix_len: u8 = match parts[1].parse() {
+        Ok(p) => p,
+        Err(_) => return Vec::new(),
+    };
+
+    let octets: Vec<&str> = base_ip.split('.').collect();
+    if octets.len() != 4 {
+        return Vec::new();
+    }
+
+    let o: Vec<u8> = match octets.iter().map(|s| s.parse()).collect() {
+        Ok(v) => v,
+        Err(_) => return Vec::new(),
+    };
+
+    let base = ((o[0] as u32) << 24) | ((o[1] as u32) << 16) | ((o[2] as u32) << 8) | (o[3] as u32);
+    if prefix_len > 32 {
+        return Vec::new();
+    }
+    let host_bits = 32 - prefix_len;
+    let num_hosts: u32 = if host_bits >= 32 { u32::MAX } else { 1u32 << host_bits };
+
+    let limit = num_hosts.min(256);
+    if limit < 2 {
+        return Vec::new();
+    }
+
+    (1..limit - 1)
+        .map(|i| {
+            let ip = base + i;
+            format!(
+                "{}.{}.{}.{}",
+                (ip >> 24) & 0xFF,
+                (ip >> 16) & 0xFF,
+                (ip >> 8) & 0xFF,
+                ip & 0xFF
+            )
+        })
+        .collect()
+}
+
+async fn validate_ips(ips: &[String], sni: &str, google_ip_validation: bool) -> Vec<String> {
+    let tls_cfg = ClientConfig::builder()
+        .dangerous()
+        .with_custom_certificate_verifier(Arc::new(NoVerify))
+        .with_no_client_auth();
+    let connector = TlsConnector::from(Arc::new(tls_cfg));
+
+    let sem = Arc::new(tokio::sync::Semaphore::new(CONCURRENCY));
+    let mut tasks = Vec::new();
+
+    for ip in ips {
+        let ip = ip.clone();
+        let sni = sni.to_string();
+        let connector = connector.clone();
+        let sem = sem.clone();
+
+        tasks.push(tokio::spawn(async move {
+            let _permit = sem.acquire().await.ok();
+            let result = quick_probe(&ip, &sni, connector, google_ip_validation).await;
+            (ip, result)
+        }));
+    }
+
+    let mut working = Vec::new();
+    for task in tasks {
+        if let Ok((ip, true)) = task.await {
+            working.push(ip);
+        }
+    }
+
+    working
+}
+async fn quick_probe(
+    ip: &str,
+    sni: &str,
+    connector: TlsConnector,
+    google_ip_validation: bool,
+) -> bool {
+    let addr: SocketAddr = match format!("{}:443", ip).parse() {
+        Ok(a) => a,
+        Err(_) => return false,
+    };
+
+    let tcp = match tokio::time::timeout(Duration::from_secs(2), TcpStream::connect(addr)).await {
+        Ok(Ok(t)) => t,
+        _ => return false,
+    };
+
+    let server_name = match ServerName::try_from(sni.to_string()) {
+        Ok(n) => n,
+        Err(_) => return false,
+    };
+
+    let mut tls =
+        match tokio::time::timeout(Duration::from_secs(2), connector.connect(server_name, tcp))
+            .await
+        {
+            Ok(Ok(t)) => t,
+            _ => return false,
+        };
+
+    let req = format!(
+        "HEAD / HTTP/1.1\r\nHost: {}\r\nConnection: close\r\n\r\n",
+        sni
+    );
+    if tls.write_all(req.as_bytes()).await.is_err() {
+        return false;
+    }
+    let _ = tls.flush().await;
+
+    let mut buf = [0u8; 1024];
+    match tokio::time::timeout(Duration::from_secs(2), tls.read(&mut buf)).await {
+        Ok(Ok(n)) if n > 0 => {
+            let response = String::from_utf8_lossy(&buf[..n]);
+
+            if !response.starts_with("HTTP/") {
+                return false;
+            }
+
+            if google_ip_validation {
+                let lower = response.to_lowercase();
+                return lower.contains("server: gws")
+                    || lower.contains("x-google-")
+                    || lower.contains("alt-svc: h3=");
+            }
+            true
+        }
+        _ => false,
+    }
+}
+
+async fn probe(
+    ip: &str,
+    sni: &str,
+    connector: TlsConnector,
+    google_ip_validation: bool,
+) -> Result_ {
     let start = Instant::now();
     let addr: SocketAddr = match format!("{}:443", ip).parse() {
         Ok(a) => a,
@@ -158,23 +575,24 @@ async fn probe(ip: &str, sni: &str, connector: TlsConnector) -> Result_ {
         }
     };
 
-    let mut tls = match tokio::time::timeout(PROBE_TIMEOUT, connector.connect(server_name, tcp)).await {
-        Ok(Ok(t)) => t,
-        Ok(Err(e)) => {
-            return Result_ {
-                ip: ip.into(),
-                latency_ms: None,
-                error: Some(format!("tls: {}", e)),
+    let mut tls =
+        match tokio::time::timeout(PROBE_TIMEOUT, connector.connect(server_name, tcp)).await {
+            Ok(Ok(t)) => t,
+            Ok(Err(e)) => {
+                return Result_ {
+                    ip: ip.into(),
+                    latency_ms: None,
+                    error: Some(format!("tls: {}", e)),
+                }
             }
-        }
-        Err(_) => {
-            return Result_ {
-                ip: ip.into(),
-                latency_ms: None,
-                error: Some("tls timeout".into()),
+            Err(_) => {
+                return Result_ {
+                    ip: ip.into(),
+                    latency_ms: None,
+                    error: Some("tls timeout".into()),
+                }
             }
-        }
-    };
+        };
 
     let req = format!(
         "HEAD / HTTP/1.1\r\nHost: {}\r\nConnection: close\r\n\r\n",
@@ -189,12 +607,29 @@ async fn probe(ip: &str, sni: &str, connector: TlsConnector) -> Result_ {
     }
     let _ = tls.flush().await;
 
-    let mut buf = [0u8; 256];
+    let mut buf = [0u8; 1024];
     match tokio::time::timeout(PROBE_TIMEOUT, tls.read(&mut buf)).await {
         Ok(Ok(n)) if n > 0 => {
-            let elapsed = start.elapsed().as_millis();
-            let head = String::from_utf8_lossy(&buf[..n.min(32)]);
-            if head.starts_with("HTTP/") {
+            let response = String::from_utf8_lossy(&buf[..n]);
+
+            if !response.starts_with("HTTP/") {
+                return Result_ {
+                    ip: ip.into(),
+                    latency_ms: None,
+                    error: Some("bad reply".into()),
+                };
+            }
+
+            let lower = response.to_lowercase();
+            let mut  is_google = true;
+            if google_ip_validation {
+                is_google = lower.contains("server: gws")
+                    || lower.contains("x-google-")
+                    || lower.contains("alt-svc: h3=");
+            }
+
+            if is_google {
+                let elapsed = start.elapsed().as_millis();
                 Result_ {
                     ip: ip.into(),
                     latency_ms: Some(elapsed),
@@ -204,7 +639,7 @@ async fn probe(ip: &str, sni: &str, connector: TlsConnector) -> Result_ {
                 Result_ {
                     ip: ip.into(),
                     latency_ms: None,
-                    error: Some(format!("bad reply: {:?}", head)),
+                    error: Some("not google frontend".into()),
                 }
             }
         }