fix: address critical/high audit findings across WASM sub-crates

- Telegram: remove .unwrap() panic on workspace_read (owner_id check)
- WhatsApp: use configured api_version instead of hardcoded v18.0
- WhatsApp: log config parse errors before falling back to defaults
- Slack: log serialization errors in emit_message and json_response
- Google Docs: safe array access for batch update replies
- Google Sheets: safe array access for add_sheet replies
- Google Calendar: fix doc comment secret name mismatch
- Gmail: avoid unnecessary String allocation in UNREAD check

Co-Authored-By: Claude Opus 4.6 <[email protected]>

channels-src/slack/src/lib.rs

@@ -338,7 +338,13 @@ fn emit_message(
         team_id,
     };
 
-    let metadata_json = serde_json::to_string(&metadata).unwrap_or_else(|_| "{}".to_string());
+    let metadata_json = serde_json::to_string(&metadata).unwrap_or_else(|e| {
+        channel_host::log(
+            channel_host::LogLevel::Error,
+            &format!("Failed to serialize Slack metadata: {}", e),
+        );
+        "{}".to_string()
+    });
 
     // Strip @ mentions of the bot from the text for cleaner messages
     let cleaned_text = strip_bot_mention(&text);
@@ -366,7 +372,13 @@ fn strip_bot_mention(text: &str) -> String {
 
 /// Create a JSON HTTP response.
 fn json_response(status: u16, value: serde_json::Value) -> OutgoingHttpResponse {
-    let body = serde_json::to_vec(&value).unwrap_or_default();
+    let body = serde_json::to_vec(&value).unwrap_or_else(|e| {
+        channel_host::log(
+            channel_host::LogLevel::Error,
+            &format!("Failed to serialize JSON response: {}", e),
+        );
+        Vec::new()
+    });
     let headers = serde_json::json!({"Content-Type": "application/json"});
 
     OutgoingHttpResponse {

channels-src/telegram/src/lib.rs

@@ -285,11 +285,7 @@ impl Guest for TelegramChannel {
         }
 
         // Persist dm_policy and allow_from for DM pairing in handle_message
-        let dm_policy = config
-            .dm_policy
-            .as_deref()
-            .unwrap_or("pairing")
-            .to_string();
+        let dm_policy = config.dm_policy.as_deref().unwrap_or("pairing").to_string();
         let _ = channel_host::workspace_write(DM_POLICY_PATH, &dm_policy);
 
         let allow_from_json = serde_json::to_string(&config.allow_from.unwrap_or_default())
@@ -844,8 +840,8 @@ fn send_pairing_reply(chat_id: i64, code: &str) -> Result<(), String> {
         "parse_mode": "Markdown",
     });
 
-    let payload_bytes = serde_json::to_vec(&payload)
-        .map_err(|e| format!("Failed to serialize payload: {}", e))?;
+    let payload_bytes =
+        serde_json::to_vec(&payload).map_err(|e| format!("Failed to serialize payload: {}", e))?;
 
     let headers = serde_json::json!({
         "Content-Type": "application/json"
@@ -915,15 +911,10 @@ fn handle_message(message: TelegramMessage) {
     let is_private = message.chat.chat_type == "private";
 
     // Owner validation: when owner_id is set, only that user can message
-    let owner_configured = channel_host::workspace_read(OWNER_ID_PATH)
-        .map(|s| !s.is_empty())
-        .unwrap_or(false);
+    let owner_id_str = channel_host::workspace_read(OWNER_ID_PATH).filter(|s| !s.is_empty());
 
-    if owner_configured {
-        if let Ok(owner_id) = channel_host::workspace_read(OWNER_ID_PATH)
-            .unwrap()
-            .parse::<i64>()
-        {
+    if let Some(ref id_str) = owner_id_str {
+        if let Ok(owner_id) = id_str.parse::<i64>() {
             if from.id != owner_id {
                 channel_host::log(
                     channel_host::LogLevel::Debug,
@@ -937,8 +928,8 @@ fn handle_message(message: TelegramMessage) {
         }
     } else if is_private {
         // No owner_id: apply dm_policy for private chats
-        let dm_policy = channel_host::workspace_read(DM_POLICY_PATH)
-            .unwrap_or_else(|| "pairing".to_string());
+        let dm_policy =
+            channel_host::workspace_read(DM_POLICY_PATH).unwrap_or_else(|| "pairing".to_string());
 
         if dm_policy != "open" {
             // Build effective allow list: config allow_from + pairing store
@@ -1001,8 +992,7 @@ fn handle_message(message: TelegramMessage) {
 
         if !respond_to_all {
             let has_command = content.starts_with('/');
-            let bot_username = channel_host::workspace_read(BOT_USERNAME_PATH)
-                .unwrap_or_default();
+            let bot_username = channel_host::workspace_read(BOT_USERNAME_PATH).unwrap_or_default();
             let has_bot_mention = if bot_username.is_empty() {
                 content.contains('@')
             } else {

channels-src/whatsapp/src/lib.rs

@@ -254,10 +254,19 @@ struct WhatsAppChannel;
 
 impl Guest for WhatsAppChannel {
     fn on_start(config_json: String) -> Result<ChannelConfig, String> {
-        let config: WhatsAppConfig = serde_json::from_str(&config_json).unwrap_or(WhatsAppConfig {
-            api_version: default_api_version(),
-            reply_to_message: default_reply_to_message(),
-        });
+        let config: WhatsAppConfig = match serde_json::from_str(&config_json) {
+            Ok(c) => c,
+            Err(e) => {
+                channel_host::log(
+                    channel_host::LogLevel::Warn,
+                    &format!("Failed to parse WhatsApp config, using defaults: {}", e),
+                );
+                WhatsAppConfig {
+                    api_version: default_api_version(),
+                    reply_to_message: default_reply_to_message(),
+                }
+            }
+        };
 
         channel_host::log(
             channel_host::LogLevel::Info,
@@ -267,6 +276,9 @@ impl Guest for WhatsAppChannel {
             ),
         );
 
+        // Persist api_version in workspace so on_respond() can read it
+        let _ = channel_host::workspace_write("channels/whatsapp/api_version", &config.api_version);
+
         // WhatsApp Cloud API is webhook-only, no polling available
         Ok(ChannelConfig {
             display_name: "WhatsApp".to_string(),
@@ -327,11 +339,16 @@ impl Guest for WhatsAppChannel {
         let metadata: WhatsAppMessageMetadata = serde_json::from_str(&response.metadata_json)
             .map_err(|e| format!("Failed to parse metadata: {}", e))?;
 
+        // Read api_version from workspace (set during on_start), fallback to default
+        let api_version = channel_host::workspace_read("channels/whatsapp/api_version")
+            .filter(|s| !s.is_empty())
+            .unwrap_or_else(|| "v18.0".to_string());
+
         // Build WhatsApp API URL with token placeholder
         // Host will replace {WHATSAPP_ACCESS_TOKEN} with actual token in Authorization header
         let api_url = format!(
-            "https://graph.facebook.com/v18.0/{}/messages",
-            metadata.phone_number_id
+            "https://graph.facebook.com/{}/{}/messages",
+            api_version, metadata.phone_number_id
         );
 
         // Build sendMessage payload

tools-src/gmail/src/api.rs

@@ -136,7 +136,7 @@ fn parse_message(v: &serde_json::Value) -> Message {
         date: get_header(payload, "Date"),
         body: extract_body(payload),
         snippet: v["snippet"].as_str().unwrap_or("").to_string(),
-        is_unread: label_ids.contains(&"UNREAD".to_string()),
+        is_unread: label_ids.iter().any(|l| l == "UNREAD"),
         label_ids,
     }
 }
@@ -198,7 +198,7 @@ pub fn list_messages(
                     to: get_header(payload, "To"),
                     date: get_header(payload, "Date"),
                     snippet: msg["snippet"].as_str().unwrap_or("").to_string(),
-                    is_unread: label_ids.contains(&"UNREAD".to_string()),
+                    is_unread: label_ids.iter().any(|l| l == "UNREAD"),
                     label_ids,
                 });
             }

tools-src/google-calendar/src/lib.rs

@@ -6,7 +6,7 @@
 //! # Capabilities Required
 //!
 //! - HTTP: `www.googleapis.com/calendar/v3/*` (GET, POST, PUT, PATCH, DELETE)
-//! - Secrets: `google_calendar_token` (OAuth 2.0 token, injected automatically)
+//! - Secrets: `google_oauth_token` (OAuth 2.0 token, injected automatically)
 //!
 //! # Supported Actions
 //!

tools-src/google-docs/src/api.rs

@@ -269,8 +269,13 @@ pub fn replace_text(
 
     let parsed = batch_update_raw(document_id, vec![request])?;
 
-    let occurrences = parsed["replies"][0]["replaceAllText"]["occurrencesChanged"]
-        .as_i64()
+    let first_reply = parsed["replies"].as_array().and_then(|arr| arr.first());
+    let occurrences = first_reply
+        .map(|r| {
+            r["replaceAllText"]["occurrencesChanged"]
+                .as_i64()
+                .unwrap_or(0)
+        })
         .unwrap_or(0);
 
     Ok(ReplaceResult {

tools-src/google-sheets/src/api.rs

@@ -330,7 +330,13 @@ pub fn add_sheet(spreadsheet_id: &str, title: &str) -> Result<AddSheetResult, St
 
     let parsed = batch_update(spreadsheet_id, requests)?;
 
-    let reply = &parsed["replies"][0]["addSheet"]["properties"];
+    let reply = parsed["replies"]
+        .as_array()
+        .and_then(|arr| arr.first())
+        .map(|r| &r["addSheet"]["properties"]);
+
+    let reply = reply.ok_or("No reply from batch update")?;
+
     Ok(AddSheetResult {
         sheet: SheetInfo {
             sheet_id: reply["sheetId"].as_i64().unwrap_or(0),