v0.3.4 - Implement secure relay private key storage

- Add relay_seckey table for secure private key storage
- Implement store_relay_private_key() and get_relay_private_key() functions
- Remove relay private key from public configuration events (kind 33334)
- Update first-time startup sequence to store keys securely after DB init
- Add proper validation and error handling for private key operations
- Fix timing issue where private key storage was attempted before DB initialization
- Security improvement: relay private keys no longer exposed in public events

CLI_PORT_OVERRIDE_IMPLEMENTATION.md

@@ -1,145 +0,0 @@
-# CLI Port Override Implementation
-
-## Overview
-
-This document describes the implementation of the `-p <port>` command line option for the C Nostr Relay, which allows overriding the default relay port during first-time startup only.
-
-## Design Principles
-
-1. **First-time startup only**: Command line options only affect the initial configuration event creation
-2. **Event-based persistence**: After first startup, all configuration is managed through database events
-3. **Proper encapsulation**: All configuration logic is contained within `config.c`
-4. **Extensible design**: The CLI options structure can easily accommodate future command line options
-
-## Implementation Details
-
-### Files Modified
-
-#### `src/config.h`
-- Added `cli_options_t` structure to encapsulate command line options
-- Updated `first_time_startup_sequence()` function signature
-
-#### `src/config.c`
-- Updated `first_time_startup_sequence()` to accept CLI options parameter
-- Updated `create_default_config_event()` to accept CLI options parameter
-- Implemented port override logic in DEFAULT_CONFIG_VALUES array processing
-
-#### `src/default_config_event.h`
-- Updated function signature for `create_default_config_event()`
-- Added proper header include for `cli_options_t` definition
-
-#### `src/main.c`
-- Added command line parsing for `-p <port>` and `--port <port>`
-- Updated help text to document the new option
-- Added proper error handling for invalid port values
-- Updated function call to pass CLI options to configuration system
-
-### CLI Options Structure
-
-```c
-typedef struct {
-    int port_override;  // -1 = not set, >0 = port value
-    // Future CLI options can be added here
-} cli_options_t;
-```
-
-### Command Line Usage
-
-```bash
-# First-time startup with port override
-./c_relay_x86 -p 9090
-./c_relay_x86 --port 9090
-
-# Show help (includes new option)
-./c_relay_x86 --help
-
-# Show version
-./c_relay_x86 --version
-```
-
-### Error Handling
-
-The implementation includes robust error handling for:
-- Missing port argument: `./c_relay_x86 -p`
-- Invalid port format: `./c_relay_x86 -p invalid_port`
-- Out-of-range ports: `./c_relay_x86 -p 0` or `./c_relay_x86 -p 99999`
-
-## Behavior Verification
-
-### First-Time Startup
-When no database exists:
-1. Command line is parsed and `-p <port>` is processed
-2. CLI options are passed to `first_time_startup_sequence()`
-3. Port override is applied in `create_default_config_event()`
-4. Configuration event is created with overridden port value
-5. Relay starts on the specified port
-6. Port setting is persisted in database for future startups
-
-### Subsequent Startups
-When database already exists:
-1. Command line is still parsed (for consistency)
-2. Existing relay path is taken
-3. Configuration is loaded from database events
-4. CLI options are ignored
-5. Relay starts on port from database configuration
-
-## Testing Results
-
-### Test 1: First-time startup with port override
-```bash
-./c_relay_x86 -p 9090
-```
-**Result**: ✅ Relay starts on port 9090, configuration stored in database
-
-### Test 2: Subsequent startup ignores CLI options
-```bash
-./c_relay_x86 -p 7777
-```
-**Result**: ✅ Relay starts on port 9090 (from database), ignores `-p 7777`
-
-### Test 3: Error handling
-```bash
-./c_relay_x86 -p invalid_port
-./c_relay_x86 -p
-```
-**Result**: ✅ Proper error messages and help text displayed
-
-### Test 4: Help text
-```bash
-./c_relay_x86 --help
-```
-**Result**: ✅ Displays updated help with `-p, --port PORT` option
-
-## Database Verification
-
-The port setting is correctly stored in the database:
-```sql
-SELECT json_extract(tags, '$') FROM events WHERE kind = 33334;
-```
-Shows the overridden port value in the configuration event tags.
-
-## Future Extensions
-
-The `cli_options_t` structure is designed to be easily extended:
-
-```c
-typedef struct {
-    int port_override;        // -1 = not set, >0 = port value
-    char* description_override; // Future: relay description override
-    int max_connections_override; // Future: connection limit override
-    // Add more options as needed
-} cli_options_t;
-```
-
-## Key Design Benefits
-
-1. **Separation of Concerns**: Main function handles CLI parsing, config system handles application
-2. **First-time Only**: Prevents confusion about configuration precedence
-3. **Event-based Architecture**: Maintains consistency with the relay's event-based configuration system
-4. **Extensible**: Easy to add new command line options in the future
-5. **Robust**: Comprehensive error handling and validation
-6. **Documented**: Clear help text explains behavior to users
-
-## Summary
-
-The `-p <port>` command line option implementation successfully provides a way to override the default relay port during first-time startup while maintaining the event-based configuration architecture for ongoing operation. The implementation is robust, well-tested, and ready for production use.

relay.pid

@@ -1 +1 @@
-1190476
+1198669

relay2.log

@@ -1,35 +0,0 @@
-=== C Nostr Relay Server ===
-Event-based configuration system
-
-[INFO] Existing relay detected
-[INFO] Initializing event-based configuration system...
-[SUCCESS] Event-based configuration system initialized
-[INFO] Starting existing relay...
-  Relay pubkey: 6df436471c7965d6473e89998162e6b87cc3547d71a2db12f559a39f4596059a
-[SUCCESS] Existing relay startup prepared
-[SUCCESS] Database connection established: 6df436471c7965d6473e89998162e6b87cc3547d71a2db12f559a39f4596059a.nrdb
-[INFO] Database schema already exists, skipping initialization
-[INFO] Existing database schema version: 4
-[WARNING] No configuration event found in existing database
-[SUCCESS] Relay information initialized with default values
-[INFO] Initializing NIP-13 Proof of Work configuration
-[INFO] PoW configured in basic validation mode (default)
-[INFO] PoW Configuration: enabled=true, min_difficulty=0, validation_flags=0x1, mode=full
-[INFO] Initializing NIP-40 Expiration Timestamp configuration
-[INFO] Expiration Configuration: enabled=true, strict_mode=true, filter_responses=true, grace_period=300 seconds
-[INFO] Subscription limits: max_per_client=25, max_total=5000
-[INFO] Starting relay server...
-[INFO] Starting libwebsockets-based Nostr relay server...
-[INFO] Checking port availability: 8888
-[WARNING] Port 8888 is in use, trying port 8889 (attempt 2/5)
-[INFO] Checking port availability: 8889
-[INFO] Attempting to bind libwebsockets to port 8889
-[WARNING] WebSocket relay started on ws://127.0.0.1:8889 (configured port 8888 was unavailable)
-[SUCCESS] WebSocket relay started on ws://127.0.0.1:8889 (configured port 8888 was unavailable)
-[INFO] Received shutdown signal
-[INFO] Shutting down WebSocket server...
-[SUCCESS] WebSocket relay shut down cleanly
-[INFO] Cleaning up configuration system...
-[SUCCESS] Configuration system cleaned up
-[INFO] Database connection closed
-[SUCCESS] Server shutdown complete

relay3.log

@@ -1,37 +0,0 @@
-=== C Nostr Relay Server ===
-Event-based configuration system
-
-[INFO] Existing relay detected
-[INFO] Initializing event-based configuration system...
-[SUCCESS] Event-based configuration system initialized
-[INFO] Starting existing relay...
-  Relay pubkey: 6df436471c7965d6473e89998162e6b87cc3547d71a2db12f559a39f4596059a
-[SUCCESS] Existing relay startup prepared
-[SUCCESS] Database connection established: 6df436471c7965d6473e89998162e6b87cc3547d71a2db12f559a39f4596059a.nrdb
-[INFO] Database schema already exists, skipping initialization
-[INFO] Existing database schema version: 4
-[WARNING] No configuration event found in existing database
-[SUCCESS] Relay information initialized with default values
-[INFO] Initializing NIP-13 Proof of Work configuration
-[INFO] PoW configured in basic validation mode (default)
-[INFO] PoW Configuration: enabled=true, min_difficulty=0, validation_flags=0x1, mode=full
-[INFO] Initializing NIP-40 Expiration Timestamp configuration
-[INFO] Expiration Configuration: enabled=true, strict_mode=true, filter_responses=true, grace_period=300 seconds
-[INFO] Subscription limits: max_per_client=25, max_total=5000
-[INFO] Starting relay server...
-[INFO] Starting libwebsockets-based Nostr relay server...
-[INFO] Checking port availability: 8888
-[WARNING] Port 8888 is in use, trying port 8889 (attempt 2/5)
-[INFO] Checking port availability: 8889
-[WARNING] Port 8889 is in use, trying port 8890 (attempt 3/5)
-[INFO] Checking port availability: 8890
-[INFO] Attempting to bind libwebsockets to port 8890
-[WARNING] WebSocket relay started on ws://127.0.0.1:8890 (configured port 8888 was unavailable)
-[SUCCESS] WebSocket relay started on ws://127.0.0.1:8890 (configured port 8888 was unavailable)
-[INFO] Received shutdown signal
-[INFO] Shutting down WebSocket server...
-[SUCCESS] WebSocket relay shut down cleanly
-[INFO] Cleaning up configuration system...
-[SUCCESS] Configuration system cleaned up
-[INFO] Database connection closed
-[SUCCESS] Server shutdown complete

src/config.c

@@ -29,6 +29,9 @@ static cJSON* g_current_config = NULL;
 // Cache for initial configuration event (before database is initialized)
 static cJSON* g_pending_config_event = NULL;
 
+// Temporary storage for relay private key during first-time setup
+static char g_temp_relay_privkey[65] = {0};
+
 // ================================
 // UTILITY FUNCTIONS
 // ================================
@@ -437,6 +440,103 @@ int generate_random_private_key_bytes(unsigned char* privkey_bytes) {
     return 0;
 }
 
+// ================================
+// SECURE RELAY PRIVATE KEY STORAGE
+// ================================
+
+int store_relay_private_key(const char* relay_privkey_hex) {
+    if (!relay_privkey_hex) {
+        log_error("Invalid relay private key for storage");
+        return -1;
+    }
+    
+    // Validate private key format (must be 64 hex characters)
+    if (strlen(relay_privkey_hex) != 64) {
+        log_error("Invalid relay private key length (must be 64 hex characters)");
+        return -1;
+    }
+    
+    // Validate hex format
+    for (int i = 0; i < 64; i++) {
+        char c = relay_privkey_hex[i];
+        if (!((c >= '0' && c <= '9') ||
+              (c >= 'a' && c <= 'f') ||
+              (c >= 'A' && c <= 'F'))) {
+            log_error("Invalid relay private key format (must be hex characters only)");
+            return -1;
+        }
+    }
+    
+    if (!g_db) {
+        log_error("Database not available for relay private key storage");
+        return -1;
+    }
+    
+    const char* sql = "INSERT OR REPLACE INTO relay_seckey (private_key_hex) VALUES (?)";
+    sqlite3_stmt* stmt;
+    
+    int rc = sqlite3_prepare_v2(g_db, sql, -1, &stmt, NULL);
+    if (rc != SQLITE_OK) {
+        log_error("Failed to prepare relay private key storage query");
+        return -1;
+    }
+    
+    sqlite3_bind_text(stmt, 1, relay_privkey_hex, -1, SQLITE_STATIC);
+    
+    rc = sqlite3_step(stmt);
+    sqlite3_finalize(stmt);
+    
+    if (rc == SQLITE_DONE) {
+        log_success("Relay private key stored securely in database");
+        return 0;
+    } else {
+        log_error("Failed to store relay private key in database");
+        return -1;
+    }
+}
+
+char* get_relay_private_key(void) {
+    if (!g_db) {
+        log_error("Database not available for relay private key retrieval");
+        return NULL;
+    }
+    
+    const char* sql = "SELECT private_key_hex FROM relay_seckey";
+    sqlite3_stmt* stmt;
+    
+    int rc = sqlite3_prepare_v2(g_db, sql, -1, &stmt, NULL);
+    if (rc != SQLITE_OK) {
+        log_error("Failed to prepare relay private key retrieval query");
+        return NULL;
+    }
+    
+    char* private_key = NULL;
+    if (sqlite3_step(stmt) == SQLITE_ROW) {
+        const char* key_from_db = (const char*)sqlite3_column_text(stmt, 0);
+        if (key_from_db && strlen(key_from_db) == 64) {
+            private_key = malloc(65);  // 64 chars + null terminator
+            if (private_key) {
+                strcpy(private_key, key_from_db);
+            }
+        }
+    }
+    
+    sqlite3_finalize(stmt);
+    
+    if (!private_key) {
+        log_error("Relay private key not found in secure storage");
+    }
+    
+    return private_key;
+}
+
+const char* get_temp_relay_private_key(void) {
+    if (strlen(g_temp_relay_privkey) == 64) {
+        return g_temp_relay_privkey;
+    }
+    return NULL;
+}
+
 // ================================
 // DEFAULT CONFIG EVENT CREATION
 // ================================
@@ -471,10 +571,8 @@ cJSON* create_default_config_event(const unsigned char* admin_privkey_bytes,
     cJSON_AddItemToArray(relay_pubkey_tag, cJSON_CreateString(relay_pubkey_hex));
     cJSON_AddItemToArray(tags, relay_pubkey_tag);
     
-    cJSON* relay_privkey_tag = cJSON_CreateArray();
-    cJSON_AddItemToArray(relay_privkey_tag, cJSON_CreateString("relay_privkey"));
-    cJSON_AddItemToArray(relay_privkey_tag, cJSON_CreateString(relay_privkey_hex));
-    cJSON_AddItemToArray(tags, relay_privkey_tag);
+    // Note: relay_privkey is now stored securely in relay_seckey table
+    // It is no longer included in the public configuration event
     
     // Add all default configuration values with command line overrides
     for (size_t i = 0; i < DEFAULT_CONFIG_COUNT; i++) {
@@ -583,14 +681,19 @@ int first_time_startup_sequence(const cli_options_t* cli_options) {
         return -1;
     }
     
-    // 5. Create initial configuration event using defaults
+    // 5. Store relay private key in temporary storage for later secure storage
+    strncpy(g_temp_relay_privkey, relay_privkey, sizeof(g_temp_relay_privkey) - 1);
+    g_temp_relay_privkey[sizeof(g_temp_relay_privkey) - 1] = '\0';
+    log_info("Relay private key cached for secure storage after database initialization");
+    
+    // 6. Create initial configuration event using defaults (without private key)
     cJSON* config_event = create_default_config_event(admin_privkey_bytes, relay_privkey, relay_pubkey, cli_options);
     if (!config_event) {
         log_error("Failed to create default configuration event");
         return -1;
     }
     
-    // 6. Try to store configuration event in database, but cache it if database isn't ready
+    // 7. Try to store configuration event in database, but cache it if database isn't ready
     if (store_config_event_in_database(config_event) == 0) {
         log_success("Initial configuration event stored successfully");
     } else {
@@ -602,16 +705,16 @@ int first_time_startup_sequence(const cli_options_t* cli_options) {
         g_pending_config_event = cJSON_Duplicate(config_event, 1);
     }
     
-    // 7. Cache the current config
+    // 8. Cache the current config
     if (g_current_config) {
         cJSON_Delete(g_current_config);
     }
     g_current_config = cJSON_Duplicate(config_event, 1);
     
-    // 8. Clean up
+    // 9. Clean up
     cJSON_Delete(config_event);
     
-    // 9. Print admin private key for user to save
+    // 10. Print admin private key for user to save
     printf("\n");
     printf("=================================================================\n");
     printf("IMPORTANT: SAVE THIS ADMIN PRIVATE KEY SECURELY!\n");

src/config.h

@@ -79,4 +79,9 @@ int apply_runtime_config_handlers(const cJSON* old_event, const cJSON* new_event
 char** find_existing_db_files(void);
 char* extract_pubkey_from_filename(const char* filename);
 
+// Secure relay private key storage functions
+int store_relay_private_key(const char* relay_privkey_hex);
+char* get_relay_private_key(void);
+const char* get_temp_relay_private_key(void);  // For first-time startup only
+
 #endif /* CONFIG_H */

src/main.c

@@ -3227,7 +3227,7 @@ int main(int argc, char* argv[]) {
             return 1;
         }
         
-        // Run first-time startup sequence (generates keys, creates database, etc.)
+        // Run first-time startup sequence (generates keys, sets up database path, but doesn't store private key yet)
         if (first_time_startup_sequence(&cli_options) != 0) {
             log_error("Failed to complete first-time startup sequence");
             cleanup_configuration_system();
@@ -3243,6 +3243,23 @@ int main(int argc, char* argv[]) {
             return 1;
         }
         
+        // Now that database is available, store the relay private key securely
+        const char* relay_privkey = get_temp_relay_private_key();
+        if (relay_privkey) {
+            if (store_relay_private_key(relay_privkey) != 0) {
+                log_error("Failed to store relay private key securely after database initialization");
+                cleanup_configuration_system();
+                nostr_cleanup();
+                return 1;
+            }
+            log_success("Relay private key stored securely in database");
+        } else {
+            log_error("Relay private key not available from first-time startup");
+            cleanup_configuration_system();
+            nostr_cleanup();
+            return 1;
+        }
+        
         // Retry storing the configuration event now that database is initialized
         if (retry_store_initial_config_event() != 0) {
             log_warning("Failed to store initial configuration event after database init");

src/sql_schema.h

@@ -1,12 +1,12 @@
 /* Embedded SQL Schema for C Nostr Relay
  * Generated from db/schema.sql - Do not edit manually
- * Schema Version: 4
+ * Schema Version: 5
  */
 #ifndef SQL_SCHEMA_H
 #define SQL_SCHEMA_H
 
 /* Schema version constant */
-#define EMBEDDED_SCHEMA_VERSION "4"
+#define EMBEDDED_SCHEMA_VERSION "5"
 
 /* Embedded SQL schema as C string literal */
 static const char* const EMBEDDED_SCHEMA_SQL = 
@@ -15,7 +15,7 @@ static const char* const EMBEDDED_SCHEMA_SQL =
 -- Event-based configuration system using kind 33334 Nostr events\n\
 \n\
 -- Schema version tracking\n\
-PRAGMA user_version = 4;\n\
+PRAGMA user_version = 5;\n\
 \n\
 -- Enable foreign key support\n\
 PRAGMA foreign_keys = ON;\n\
@@ -58,8 +58,8 @@ CREATE TABLE schema_info (\n\
 \n\
 -- Insert schema metadata\n\
 INSERT INTO schema_info (key, value) VALUES\n\
-    ('version', '4'),\n\
-    ('description', 'Event-based Nostr relay schema with kind 33334 configuration events'),\n\
+    ('version', '5'),\n\
+    ('description', 'Event-based Nostr relay schema with secure relay private key storage'),\n\
     ('created_at', strftime('%s', 'now'));\n\
 \n\
 -- Helper views for common queries\n\
@@ -128,6 +128,13 @@ BEGIN\n\
     AND id != NEW.id;\n\
 END;\n\
 \n\
+-- Relay Private Key Secure Storage\n\
+-- Stores the relay's private key separately from public configuration\n\
+CREATE TABLE relay_seckey (\n\
+    private_key_hex TEXT NOT NULL CHECK (length(private_key_hex) = 64),\n\
+    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))\n\
+);\n\
+\n\
 -- Persistent Subscriptions Logging Tables (Phase 2)\n\
 -- Optional database logging for subscription analytics and debugging\n\
 \n\

test_port_increment.log

@@ -1,47 +0,0 @@
-=== C Nostr Relay Server ===
-Event-based configuration system
-
-[INFO] Existing relay detected
-[INFO] Initializing event-based configuration system...
-[SUCCESS] Event-based configuration system initialized
-[INFO] Starting existing relay...
-  Relay pubkey: 6df436471c7965d6473e89998162e6b87cc3547d71a2db12f559a39f4596059a
-[SUCCESS] Existing relay startup prepared
-[SUCCESS] Database connection established: 6df436471c7965d6473e89998162e6b87cc3547d71a2db12f559a39f4596059a.nrdb
-[INFO] Database schema already exists, skipping initialization
-[INFO] Existing database schema version: 4
-[INFO] Applying configuration from event...
-[INFO] Checking for runtime configuration changes...
-[INFO] Subscription limits changed - updating subscription manager
-[INFO] Subscription limits: max_per_client=25, max_total=5000
-[INFO] PoW configuration changed - reinitializing PoW system
-[INFO] Initializing NIP-13 Proof of Work configuration
-[INFO] PoW configured in basic validation mode
-[INFO] PoW Configuration: enabled=true, min_difficulty=0, validation_flags=0x1, mode=full
-[INFO] Expiration configuration changed - reinitializing expiration system
-[INFO] Initializing NIP-40 Expiration Timestamp configuration
-[INFO] Expiration Configuration: enabled=true, strict_mode=true, filter_responses=true, grace_period=300 seconds
-[INFO] Relay information changed - reinitializing relay info
-[SUCCESS] Relay information initialized with default values
-[SUCCESS] Configuration updated via kind 33334 event - 4 system components reinitialized
-[SUCCESS] Configuration applied from event (4 handlers executed)
-[SUCCESS] Configuration loaded from database
-[SUCCESS] Relay information initialized with default values
-[INFO] Initializing NIP-13 Proof of Work configuration
-[INFO] PoW configured in basic validation mode
-[INFO] PoW Configuration: enabled=true, min_difficulty=0, validation_flags=0x1, mode=full
-[INFO] Initializing NIP-40 Expiration Timestamp configuration
-[INFO] Expiration Configuration: enabled=true, strict_mode=true, filter_responses=true, grace_period=300 seconds
-[INFO] Subscription limits: max_per_client=25, max_total=5000
-[INFO] Starting relay server...
-[INFO] Starting libwebsockets-based Nostr relay server...
-[INFO] Attempting to bind to port 8888
-[2025/09/06 20:34:16:8170] E: ERROR on binding fd 8 to port 8888 (-1 98)
-[2025/09/06 20:34:16:8172] E: init server failed
-[2025/09/06 20:34:16:8172] E: Failed to create default vhost
-[ERROR] Failed to create libwebsockets context after 1 attempts. Last attempted port: 8888
-libwebsockets creation error: Inappropriate ioctl for device
-[INFO] Cleaning up configuration system...
-[SUCCESS] Configuration system cleaned up
-[INFO] Database connection closed
-[ERROR] Server shutdown with errors