Generate a new node identity on key generation (#7628)

* Generate a new node identity on key generation * Fixes * Fixes * Fixes * Messed up * Fixes * Update src/modules/AdminModule.cpp Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com> * Update src/mesh/NodeDB.cpp Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com> * Figured it out! * Cleanup * Update src/mesh/NodeDB.h Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com> * Update src/mesh/NodeDB.cpp Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com> * Update src/modules/AdminModule.cpp Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com> --------- Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
2025-12-24 03:31:14 +00:00 · 2025-08-14 21:06:55 -05:00
parent 359338db32
commit c5c634ee27
4 changed files with 115 additions and 77 deletions
--- a/src/graphics/draw/MenuHandler.cpp
+++ b/src/graphics/draw/MenuHandler.cpp
@@ -67,25 +67,8 @@ void menuHandler::LoraRegionPicker(uint32_t duration)
        if (selected != 0 && config.lora.region != _meshtastic_Config_LoRaConfig_RegionCode(selected)) {
            config.lora.region = _meshtastic_Config_LoRaConfig_RegionCode(selected);
            // This is needed as we wait til picking the LoRa region to generate keys for the first time.
-            if (!owner.is_licensed) {
-                bool keygenSuccess = false;
-                if (config.security.private_key.size == 32) {
-                    // public key is derived from private, so this will always have the same result.
-                    if (crypto->regeneratePublicKey(config.security.public_key.bytes, config.security.private_key.bytes)) {
-                        keygenSuccess = true;
-                    }
-                } else {
-                    LOG_INFO("Generate new PKI keys");
-                    crypto->generateKeyPair(config.security.public_key.bytes, config.security.private_key.bytes);
-                    keygenSuccess = true;
-                }
-                if (keygenSuccess) {
-                    config.security.public_key.size = 32;
-                    config.security.private_key.size = 32;
-                    owner.public_key.size = 32;
-                    memcpy(owner.public_key.bytes, config.security.public_key.bytes, 32);
-                }
-            }
+            // Use consolidated key generation function
+            nodeDB->generateCryptoKeyPair();
            config.lora.tx_enabled = true;
            initRegion();
            if (myRegion->dutyCycle < 100) {
--- a/src/mesh/NodeDB.cpp
+++ b/src/mesh/NodeDB.cpp
@@ -242,8 +242,6 @@ NodeDB::NodeDB()

    // likewise - we always want the app requirements to come from the running appload
    myNodeInfo.min_app_version = 30200; // format is Mmmss (where M is 1+the numeric major number. i.e. 30200 means 2.2.00
-    // Note! We do this after loading saved settings, so that if somehow an invalid nodenum was stored in preferences we won't
-    // keep using that nodenum forever. Crummy guess at our nodenum (but we will check against the nodedb to avoid conflicts)
    pickNewNodeNum();

    // Set our board type so we can share it with others
@@ -261,31 +259,18 @@ NodeDB::NodeDB()
    }

 #if !(MESHTASTIC_EXCLUDE_PKI_KEYGEN || MESHTASTIC_EXCLUDE_PKI)
-
-    if (!owner.is_licensed && config.lora.region != meshtastic_Config_LoRaConfig_RegionCode_UNSET) {
-        bool keygenSuccess = false;
-        keyIsLowEntropy = checkLowEntropyPublicKey(config.security.public_key);
-        if (config.security.private_key.size == 32 && !keyIsLowEntropy) {
-            if (crypto->regeneratePublicKey(config.security.public_key.bytes, config.security.private_key.bytes)) {
-                keygenSuccess = true;
-            }
-        } else {
-            crypto->generateKeyPair(config.security.public_key.bytes, config.security.private_key.bytes);
-            keygenSuccess = true;
-        }
-        if (keygenSuccess) {
-            config.security.public_key.size = 32;
-            config.security.private_key.size = 32;
-            owner.public_key.size = 32;
-            memcpy(owner.public_key.bytes, config.security.public_key.bytes, 32);
-        }
-    }
+    // Generate crypto keys if needed using consolidated function
+    // Set my node num uint32 value to bytes from the public key (if we have one)
+    // Generate identity and crypto keys if needed; this will create a new identity if one does not exist
+    generateCryptoKeyPair(nullptr);
 #elif !(MESHTASTIC_EXCLUDE_PKI)
    // Calculate Curve25519 public and private keys
    if (config.security.private_key.size == 32 && config.security.public_key.size == 32) {
        owner.public_key.size = config.security.public_key.size;
        memcpy(owner.public_key.bytes, config.security.public_key.bytes, config.security.public_key.size);
        crypto->setDHPrivateKey(config.security.private_key.bytes);
+        // Set my node num uint32 value to bytes from the new public key
+        myNodeInfo.my_node_num = crc32Buffer(config.security.public_key.bytes, config.security.public_key.size);
    }
 #endif
    // Include our owner in the node db under our nodenum
@@ -1876,6 +1861,94 @@ bool NodeDB::checkLowEntropyPublicKey(const meshtastic_Config_SecurityConfig_pub
    return false;
 }

+bool NodeDB::generateCryptoKeyPair(const uint8_t *privateKey)
+{
+#if !(MESHTASTIC_EXCLUDE_PKI_KEYGEN || MESHTASTIC_EXCLUDE_PKI)
+    // Only generate keys for non-licensed users and if LoRa region is set
+    if (owner.is_licensed || config.lora.region == meshtastic_Config_LoRaConfig_RegionCode_UNSET) {
+        return false;
+    }
+
+    bool keygenSuccess = false;
+    bool lowEntropy = checkLowEntropyPublicKey(config.security.public_key);
+
+    // If a specific private key was provided, use it
+    if (privateKey != nullptr) {
+        LOG_INFO("Using provided private key for PKI");
+        memcpy(config.security.private_key.bytes, privateKey, 32);
+        config.security.private_key.size = 32;
+        config.security.public_key.size = 32;
+
+        // Generate public key from the provided private key
+        if (crypto->regeneratePublicKey(config.security.public_key.bytes, config.security.private_key.bytes)) {
+            keygenSuccess = true;
+        } else {
+            LOG_ERROR("Failed to generate public key from provided private key");
+            return false;
+        }
+    }
+    // Try to regenerate public key from existing private key if it's valid and not low entropy
+    else if (config.security.private_key.size == 32 && !lowEntropy) {
+        config.security.public_key.size = 32;
+        LOG_DEBUG("Regenerate PKI public key from existing private key");
+        if (crypto->regeneratePublicKey(config.security.public_key.bytes, config.security.private_key.bytes)) {
+            keygenSuccess = true;
+        }
+    } else {
+        // Generate a new key pair
+        LOG_INFO("Generate new PKI keys");
+        config.security.public_key.size = 32;
+        config.security.private_key.size = 32;
+        crypto->generateKeyPair(config.security.public_key.bytes, config.security.private_key.bytes);
+        keygenSuccess = true;
+    }
+
+    // Update sizes and copy to owner if successful
+    if (keygenSuccess) {
+        owner.public_key.size = 32;
+        memcpy(owner.public_key.bytes, config.security.public_key.bytes, 32);
+
+        // Update global entropy flag for UI display
+        keyIsLowEntropy = false;
+
+        // Set the DH private key for crypto operations
+        LOG_DEBUG("Set DH private key for crypto operations");
+        crypto->setDHPrivateKey(config.security.private_key.bytes);
+
+        // Conditionally create new identity based on parameter
+        createNewIdentity();
+    }
+    return keygenSuccess;
+#else
+    return false;
+#endif
+}
+
+bool NodeDB::createNewIdentity()
+{
+    // Remove the old node from the NodeDB
+    uint32_t oldNodeNum = getNodeNum();
+    meshtastic_NodeInfoLite *node = getMeshNode(oldNodeNum);
+
+    // Set my node num uint32 value to bytes from the new public key
+    myNodeInfo.my_node_num = crc32Buffer(config.security.public_key.bytes, config.security.public_key.size);
+
+    if (node != NULL && myNodeInfo.my_node_num != oldNodeNum) {
+        LOG_DEBUG("Old node num %u is now %u", oldNodeNum, myNodeInfo.my_node_num);
+        node->is_ignored = true;
+        node->has_device_metrics = false;
+        node->has_position = false;
+        node->user.public_key.size = 0;
+        node->user.public_key.bytes[0] = 0;
+    }
+
+    meshtastic_NodeInfoLite *info = getOrCreateMeshNode(getNodeNum());
+    info->user = TypeConversions::ConvertToUserLite(owner);
+    info->has_user = true;
+
+    return true;
+}
+
 bool NodeDB::backupPreferences(meshtastic_AdminMessage_BackupLocation location)
 {
    bool success = false;
--- a/src/mesh/NodeDB.h
+++ b/src/mesh/NodeDB.h
@@ -270,6 +270,12 @@ class NodeDB

    bool checkLowEntropyPublicKey(const meshtastic_Config_SecurityConfig_public_key_t &keyToTest);

+    /// Consolidate crypto key generation logic used across multiple modules
+    /// @param privateKey Optional 32-byte private key to use. If nullptr, generates new random keys.
+    bool generateCryptoKeyPair(const uint8_t *privateKey = nullptr);
+
+    bool createNewIdentity();
+
    bool backupPreferences(meshtastic_AdminMessage_BackupLocation location);
    bool restorePreferences(meshtastic_AdminMessage_BackupLocation location,
                            int restoreWhat = SEGMENT_CONFIG | SEGMENT_MODULECONFIG | SEGMENT_DEVICESTATE | SEGMENT_CHANNELS);
--- a/src/modules/AdminModule.cpp
+++ b/src/modules/AdminModule.cpp
@@ -729,24 +729,8 @@ void AdminModule::handleSetConfig(const meshtastic_Config &c)
        config.lora = c.payload_variant.lora;
        // If we're setting region for the first time, init the region and regenerate the keys
        if (isRegionUnset && config.lora.region > meshtastic_Config_LoRaConfig_RegionCode_UNSET) {
-            if (!owner.is_licensed) {
-                bool keygenSuccess = false;
-                if (config.security.private_key.size == 32) {
-                    if (crypto->regeneratePublicKey(config.security.public_key.bytes, config.security.private_key.bytes)) {
-                        keygenSuccess = true;
-                    }
-                } else {
-                    LOG_INFO("Generate new PKI keys");
-                    crypto->generateKeyPair(config.security.public_key.bytes, config.security.private_key.bytes);
-                    keygenSuccess = true;
-                }
-                if (keygenSuccess) {
-                    config.security.public_key.size = 32;
-                    config.security.private_key.size = 32;
-                    owner.public_key.size = 32;
-                    memcpy(owner.public_key.bytes, config.security.public_key.bytes, 32);
-                }
-            }
+            // Use consolidated key generation function
+            nodeDB->generateCryptoKeyPair();
            config.lora.tx_enabled = true;
            initRegion();
            if (myRegion->dutyCycle < 100) {
@@ -754,7 +738,7 @@ void AdminModule::handleSetConfig(const meshtastic_Config &c)
            }
            if (strcmp(moduleConfig.mqtt.root, default_mqtt_root) == 0) {
                sprintf(moduleConfig.mqtt.root, "%s/%s", default_mqtt_root, myRegion->name);
-                changes = SEGMENT_CONFIG | SEGMENT_MODULECONFIG;
+                changes = SEGMENT_CONFIG | SEGMENT_MODULECONFIG | SEGMENT_NODEDATABASE | SEGMENT_DEVICESTATE;
            }
        }
        break;
@@ -767,22 +751,14 @@ void AdminModule::handleSetConfig(const meshtastic_Config &c)
        LOG_INFO("Set config: Security");
        config.security = c.payload_variant.security;
 #if !(MESHTASTIC_EXCLUDE_PKI_KEYGEN) && !(MESHTASTIC_EXCLUDE_PKI)
-        // If the client set the key to blank, go ahead and regenerate so long as we're not in ham mode
-        if (!owner.is_licensed && config.lora.region != meshtastic_Config_LoRaConfig_RegionCode_UNSET) {
-            if (config.security.private_key.size != 32) {
-                crypto->generateKeyPair(config.security.public_key.bytes, config.security.private_key.bytes);
-
-            } else {
-                if (crypto->regeneratePublicKey(config.security.public_key.bytes, config.security.private_key.bytes)) {
-                    config.security.public_key.size = 32;
-                }
-            }
+        // Only regenerate keys if the private key is not 32 bytes
+        if (config.security.private_key.size != 32) {
+            nodeDB->generateCryptoKeyPair();
+        }
+        // If user provided a private key of correct size but no public key, generate the public key from private key
+        else if (config.security.private_key.size == 32 && config.security.public_key.size == 0) {
+            nodeDB->generateCryptoKeyPair(config.security.private_key.bytes);
        }
-#endif
-        owner.public_key.size = config.security.public_key.size;
-        memcpy(owner.public_key.bytes, config.security.public_key.bytes, config.security.public_key.size);
-#if !MESHTASTIC_EXCLUDE_PKI
-        crypto->setDHPrivateKey(config.security.private_key.bytes);
 #endif
        if (config.security.is_managed && !(config.security.admin_key[0].size == 32 || config.security.admin_key[1].size == 32 ||
                                            config.security.admin_key[2].size == 32)) {
@@ -792,9 +768,9 @@ void AdminModule::handleSetConfig(const meshtastic_Config &c)
            sendWarning(warning);
        }

-        if (config.security.debug_log_api_enabled == c.payload_variant.security.debug_log_api_enabled &&
-            config.security.serial_enabled == c.payload_variant.security.serial_enabled)
-            requiresReboot = false;
+        changes = SEGMENT_CONFIG | SEGMENT_DEVICESTATE | SEGMENT_NODEDATABASE;
+
+        requiresReboot = true;

        break;
    case meshtastic_Config_device_ui_tag: