Merge branch '26-notification-hook-triggered-on-startup' into 'master'

Run notification hook on startup

Closes #26

See merge request !22

README.md

+# Usage
+
+`cryptops-api --root-device=DEV --crypt-name=LABEL [--notify-command=COMMAND]`
+
+*   The `--root-device=DEV` option is mandatory. `DEV` should be the root device
+    of the machine, like `/dev/sda` or `/dev/xvda`.
+    
+    When the root device is still unencrypted (for example when starting
+    cryptops-api for the first time), this should be an unpartitioned device,
+    with the file system spanning the whole device.
+    
+    As part of the encryption process, this device will be partitioned and the
+    encrypted contents will be stored on the second partition, but DEV should
+    still point to the whole device, as before.
+
+*   The `--crypt-name=LABEL` option is mandatory. `LABEL` will be used by
+    cryptsetup to name the encrypted volume. This will be visible to the operating
+    system, as the decrypted root disk is available at `/dev/mapper/LABEL`.
+
+*   The `--notify-command=COMMAND` option is optional. The given `COMMAND` will be
+    run whenever cryptops-api detects that the root device needs the user to enter
+    their password to continue the booting process. You can use this to notify the
+    user of this situation.

src/cryptops-api.c

@@ -28,11 +28,26 @@ int main(int argc, char ** argv)
     y_init_logs("cryptops-api", Y_LOG_MODE_CONSOLE, Y_LOG_LEVEL_DEBUG,
         NULL, "Starting cryptops-api");
 
-    y_log_message(Y_LOG_LEVEL_DEBUG, "root_device: %s", config.root_device);
-    y_log_message(Y_LOG_LEVEL_DEBUG, "info_partition_device: %s", config.info_partition_device);
-    y_log_message(Y_LOG_LEVEL_DEBUG, "data_partition_device: %s", config.data_partition_device);
-    y_log_message(Y_LOG_LEVEL_DEBUG, "mapped_device_name: %s", config.mapped_device_name);
-    y_log_message(Y_LOG_LEVEL_DEBUG, "mapped_device_path: %s", config.mapped_device_path);
+    y_log_message(Y_LOG_LEVEL_DEBUG, "root_device: %s",
+        config.root_device);
+    y_log_message(Y_LOG_LEVEL_DEBUG, "info_partition_device: %s",
+        config.info_partition_device);
+    y_log_message(Y_LOG_LEVEL_DEBUG, "data_partition_device: %s",
+        config.data_partition_device);
+    y_log_message(Y_LOG_LEVEL_DEBUG, "mapped_device_name: %s",
+        config.mapped_device_name);
+    y_log_message(Y_LOG_LEVEL_DEBUG, "mapped_device_path: %s",
+        config.mapped_device_path);
+    y_log_message(Y_LOG_LEVEL_DEBUG, "notify_command: %s",
+        config.notify_command);
+
+    // Check if the root device is encrypted, and if so, use the supplied
+    // command to notify the user.
+    if (path_exists(config.data_partition_device) &&
+        is_encrypted_device(config.data_partition_device))
+    {
+        system(config.notify_command);
+    }
 
     // Set address to bind to.
     struct sockaddr_in address;
@@ -150,6 +165,7 @@ int main(int argc, char ** argv)
     if (reboot)
     {
         y_log_message(Y_LOG_LEVEL_INFO, "rebooting...");
+        y_close_logs();
         reboot_initrd(true);
     }
 
@@ -157,6 +173,7 @@ int main(int argc, char ** argv)
     if (shutdown)
     {
         y_log_message(Y_LOG_LEVEL_INFO, "shutting down...");
+        y_close_logs();
         reboot_initrd(false);
     }
 

src/includes/common-includes.h

@@ -11,6 +11,7 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <unistd.h>
+#include <getopt.h>
 #include <sys/reboot.h>
 
 #define U_DISABLE_CURL

src/runtime-config.c

@@ -6,20 +6,91 @@ struct config
     char * mapped_device_name;
     char * mapped_device_path;
     char * tmp_data_location;
+    char * notify_command;
 };
 extern struct config config;
 struct config config;
 
+void print_usage()
+{
+    printf("Usage:\n");
+    printf("  cryptops-api --root-device=DEV --crypt-name=LABEL "
+        " [--notify-command=COMMAND]\n");
+}
+
 void set_config_from_arguments(int argc, char ** argv)
 {
-    if (argc < 3)
+    // Set defaults.
+    char * crypt_name = NULL;
+    char * notify_command = "";
+    char * root_device = NULL;
+
+    static struct option long_options[] =
+    {
+        {"crypt-name"    ,  required_argument, 0, 'c'},
+        {"notify-command",  required_argument, 0, 'n'},
+        {"root-device"   ,  required_argument, 0, 'r'},
+        {0, 0, 0, 0}
+    };
+    int option_index = 0;
+    int c;
+
+    while (true)
+    {
+        c = getopt_long(argc, argv, "c:n:r:", long_options, &option_index);
+
+        // Check if we have dealt with all options.
+        if (c == -1)
+        {
+            break;
+        }
+
+        switch (c)
+        {
+            case 'c':
+                crypt_name = optarg;
+                break;
+            case 'n':
+                notify_command = optarg;
+                break;
+            case 'r':
+                root_device = optarg;
+                break;
+            case '?':
+                // getopt_long already printed an error message.
+                break;
+            default:
+                abort();
+        }
+    }
+
+    // Print any remaining command line arguments (not options).
+    if (optind < argc)
+    {
+        printf("non-option ARGV-elements: ");
+        while (optind < argc)
+        {
+            printf("%s ", argv[optind++]);
+        }
+        putchar('\n');
+    }
+
+    if (root_device == NULL)
+    {
+        printf("Required option --root-device missing.\n");
+        print_usage();
+        exit(1);
+    }
+    if (crypt_name == NULL)
     {
-        printf("Not enough arguments. Usage:\n  cryptops-api ROOTDEV CRYPTNAME\n");
+        printf("Required option --crypt-name missing.\n");
+        print_usage();
         exit(1);
     }
 
-    config.root_device = argv[1];
-    config.mapped_device_name = argv[2];
+    config.root_device = root_device;
+    config.mapped_device_name = crypt_name;
+    config.notify_command = notify_command;
 
     asprintf(&config.info_partition_device, "%s1", config.root_device);
     asprintf(&config.data_partition_device, "%s2", config.root_device);