RDKEMW-24199: Fixed GetKnownSSIDs for expected response - #348

This PR updates the NetworkManager plugin’s “known SSIDs” retrieval to return saved WiFi profile information even when the device is disconnected (notably on RDKV), by switching the RDK backend to query the paired/saved SSID rather than the currently connected SSID.

Changes:

• Add an IARM API identifier for retrieving the saved/paired SSID on RDK (getPairedSSID).
• Update the RDK implementation of GetKnownSSIDs to call getPairedSSID instead of getConnectedSSID.
• Adjust the GNOME implementation of GetKnownSSIDs to always build an iterator (even when no SSIDs are found).

• Files reviewed: 3/3 changed files
• Comments generated: 2
• Review effort level: Lite

Suppressed comments (2)

plugin/rdk/NetworkManagerRDKProxy.cpp:1051

• GetKnownSSIDs currently unconditionally pushes the returned pairedSsid.ssid into ssidList. If the IARM call succeeds but there is no paired SSID (empty string), this will serialize as [""] instead of an empty list, which is not a valid SSID value and can confuse clients.

                auto &pairedSsid = param.data.getPairedSSID;
                std::list<string> ssidList;
                ssidList.push_back(string(pairedSsid.ssid));

plugin/gnome/NetworkManagerGnomeProxy.cpp:773

• When ssidList is empty, this code inserts an empty string element. That will make the RPC/JSON response contain [""] instead of an empty array, which is semantically different and treats "no SSIDs" as a single SSID with an empty name.

                if (ssidList.empty())
                {
                    NMLOG_INFO("known ssids not found !");
                    ssidList.push_back(string());
                }

• Files reviewed: 4/4 changed files
• Comments generated: 0 new
• Review effort level: Lite

Suppressed comments (3)

plugin/NetworkManagerImplementation.cpp:559

• -i 0.002 requests a 2 ms interval. For counts greater than one this can burst up to 500 packets per second, and standard iputils rejects intervals below 200 ms for unprivileged callers, so Ping can either fail or create an avoidable CPU/network burst. Keep a supported interval or explicitly cap/validate the request and privilege requirements before using such a value.

                snprintf(cmd, sizeof(cmd), "ping6 -c %d -W %d -i 0.002 '%s' 2>&1", noOfRequest, timeOutInSeconds, endpoint.c_str());
            }
            else
            {
                snprintf(cmd, sizeof(cmd), "ping  -c %d -W %d -i 0.002 '%s' 2>&1", noOfRequest, timeOutInSeconds, endpoint.c_str());

plugin/NetworkManagerJsonRpc.cpp:585

• The title and description only cover the RDK GetKnownSSIDs fix, but this hunk changes Ping defaults; the same diff also changes the ping interval and wake-up scan behavior. These are independent runtime changes not represented in the stated test procedure or low-risk assessment. Please split them into scoped changes or update the description, risk, and tests to cover them.

                uint32_t noOfRequest = 1;
                uint16_t timeOutInSeconds = 1;

plugin/gnome/NetworkManagerGnomeProxy.cpp:773

• The newly added empty-list branch does not handle the no-profile case with the current backend: wifiManager::getKnownSSIDs returns false when ssids is empty (NetworkManagerGnomeWIFI.cpp:1850-1858), so execution never reaches this block and the API still returns success:false. Propagate an empty list as a successful result from the backend, and keep it empty rather than adding a non-existent SSID.

                if (ssidList.empty())
                {
                    NMLOG_INFO("known ssids not found !");
                    ssidList.push_back(string());
                }

• Files reviewed: 11/11 changed files
• Comments generated: 2
• Review effort level: Lite