discover: extend URL in UI to support auto-discovery
[petitboot] / discover / device-handler.c
index a497147918d43232498d23eeb833b4101d1ec6c0..5df070073b4d298c8a49a5488010434b73ff4f32 100644 (file)
@@ -1,4 +1,3 @@
-
 #include <assert.h>
 #include <stdlib.h>
 #include <stdbool.h>
@@ -6,10 +5,11 @@
 #include <string.h>
 #include <errno.h>
 #include <mntent.h>
+#include <locale.h>
 #include <sys/stat.h>
 #include <sys/wait.h>
+#include <sys/mount.h>
 
-#include <pb-config/pb-config.h>
 #include <talloc/talloc.h>
 #include <list/list.h>
 #include <log/log.h>
 #include <system/system.h>
 #include <process/process.h>
 #include <url/url.h>
+#include <i18n/i18n.h>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netdb.h>
+#include <arpa/inet.h>
 
 #include "device-handler.h"
 #include "discover-server.h"
+#include "devmapper.h"
+#include "user-event.h"
+#include "platform.h"
 #include "event.h"
 #include "parser.h"
 #include "resource.h"
 #include "paths.h"
+#include "sysinfo.h"
 #include "boot.h"
+#include "udev.h"
+#include "network.h"
+#include "ipmi.h"
+
+enum default_priority {
+       DEFAULT_PRIORITY_REMOTE         = 1,
+       DEFAULT_PRIORITY_LOCAL_FIRST    = 2,
+       DEFAULT_PRIORITY_LOCAL_LAST     = 0xfe,
+       DEFAULT_PRIORITY_DISABLED       = 0xff,
+};
 
 struct device_handler {
        struct discover_server  *server;
        int                     dry_run;
 
+       struct pb_udev          *udev;
+       struct network          *network;
+       struct user_event       *user_event;
+
        struct discover_device  **devices;
        unsigned int            n_devices;
 
+       struct ramdisk_device   **ramdisks;
+       unsigned int            n_ramdisks;
+
        struct waitset          *waitset;
        struct waiter           *timeout_waiter;
        bool                    autoboot_enabled;
        unsigned int            sec_to_boot;
 
        struct discover_boot_option *default_boot_option;
+       int                     default_boot_option_priority;
+
        struct list             unresolved_boot_options;
 
        struct boot_task        *pending_boot;
@@ -48,6 +77,11 @@ struct device_handler {
 static int mount_device(struct discover_device *dev);
 static int umount_device(struct discover_device *dev);
 
+static int device_handler_init_sources(struct device_handler *handler);
+static void device_handler_reinit_sources(struct device_handler *handler);
+
+static void device_handler_update_lang(const char *lang);
+
 void discover_context_add_boot_option(struct discover_context *ctx,
                struct discover_boot_option *boot_option)
 {
@@ -250,7 +284,7 @@ const char *discover_device_get_param(struct discover_device *device,
 
        list_for_each_entry(&device->params, param, list) {
                if (!strcmp(param->name, name))
-                       return param->name;
+                       return param->value;
        }
        return NULL;
 }
@@ -259,6 +293,7 @@ struct device_handler *device_handler_init(struct discover_server *server,
                struct waitset *waitset, int dry_run)
 {
        struct device_handler *handler;
+       int rc;
 
        handler = talloc_zero(NULL, struct device_handler);
        handler->server = server;
@@ -273,12 +308,55 @@ struct device_handler *device_handler_init(struct discover_server *server,
 
        parser_init();
 
+       if (config_get()->safe_mode)
+               return handler;
+
+       rc = device_handler_init_sources(handler);
+       if (rc) {
+               talloc_free(handler);
+               return NULL;
+       }
+
        return handler;
 }
 
+void device_handler_reinit(struct device_handler *handler)
+{
+       struct discover_boot_option *opt, *tmp;
+       struct ramdisk_device *ramdisk;
+       unsigned int i;
+
+       device_handler_cancel_default(handler);
+
+       /* free unresolved boot options */
+       list_for_each_entry_safe(&handler->unresolved_boot_options,
+                       opt, tmp, list)
+               talloc_free(opt);
+       list_init(&handler->unresolved_boot_options);
+
+       /* drop all devices */
+       for (i = 0; i < handler->n_devices; i++) {
+               discover_server_notify_device_remove(handler->server,
+                               handler->devices[i]->device);
+               ramdisk = handler->devices[i]->ramdisk;
+               talloc_free(handler->devices[i]);
+               talloc_free(ramdisk);
+       }
+
+       talloc_free(handler->devices);
+       handler->devices = NULL;
+       handler->n_devices = 0;
+       talloc_free(handler->ramdisks);
+       handler->ramdisks = NULL;
+       handler->n_ramdisks = 0;
+
+       device_handler_reinit_sources(handler);
+}
+
 void device_handler_remove(struct device_handler *handler,
                struct discover_device *device)
 {
+       struct discover_boot_option *opt, *tmp;
        unsigned int i;
 
        for (i = 0; i < handler->n_devices; i++)
@@ -290,6 +368,21 @@ void device_handler_remove(struct device_handler *handler,
                return;
        }
 
+       /* Free any unresolved options, as they're currently allocated
+        * against the handler */
+       list_for_each_entry_safe(&handler->unresolved_boot_options,
+                       opt, tmp, list) {
+               if (opt->device != device)
+                       continue;
+               list_remove(&opt->list);
+               talloc_free(opt);
+       }
+
+       /* if this is a network device, we have to unregister it from the
+        * network code */
+       if (device->device->type == DEVICE_TYPE_NETWORK)
+               network_unregister_device(handler->network, device);
+
        handler->n_devices--;
        memmove(&handler->devices[i], &handler->devices[i + 1],
                (handler->n_devices - i) * sizeof(handler->devices[0]));
@@ -319,7 +412,7 @@ static void countdown_status(struct device_handler *handler,
        status.progress = -1;
        status.detail = NULL;
        status.message = talloc_asprintf(handler,
-                       "Booting %s in %u sec", opt->option->name, sec);
+                       _("Booting in %d sec: %s"), sec, opt->option->name);
 
        discover_server_notify_boot_status(handler->server, &status);
 
@@ -358,46 +451,125 @@ static int default_timeout(void *arg)
        return 0;
 }
 
-static bool priority_match(struct boot_priority *prio,
-               struct discover_boot_option *opt)
+struct {
+       enum ipmi_bootdev       ipmi_type;
+       enum device_type        device_type;
+} device_type_map[] = {
+       { IPMI_BOOTDEV_NETWORK, DEVICE_TYPE_NETWORK },
+       { IPMI_BOOTDEV_DISK, DEVICE_TYPE_DISK },
+       { IPMI_BOOTDEV_DISK, DEVICE_TYPE_USB },
+       { IPMI_BOOTDEV_CDROM, DEVICE_TYPE_OPTICAL },
+};
+
+static bool ipmi_device_type_matches(enum ipmi_bootdev ipmi_type,
+               enum device_type device_type)
 {
-       return prio->type == opt->device->device->type;
+       unsigned int i;
+
+       for (i = 0; i < ARRAY_SIZE(device_type_map); i++) {
+               if (device_type_map[i].device_type == device_type)
+                       return device_type_map[i].ipmi_type == ipmi_type;
+       }
+
+       return false;
+}
+
+static int autoboot_option_priority(const struct config *config,
+                               struct discover_boot_option *opt)
+{
+       enum device_type type = opt->device->device->type;
+       const char *uuid = opt->device->uuid;
+       struct autoboot_option *auto_opt;
+       unsigned int i;
+
+       for (i = 0; i < config->n_autoboot_opts; i++) {
+               auto_opt = &config->autoboot_opts[i];
+               if (auto_opt->boot_type == BOOT_DEVICE_UUID)
+                       if (!strcmp(auto_opt->uuid, uuid))
+                               return DEFAULT_PRIORITY_LOCAL_FIRST + i;
+
+               if (auto_opt->boot_type == BOOT_DEVICE_TYPE)
+                       if (auto_opt->type == type ||
+                           auto_opt->type == DEVICE_TYPE_ANY)
+                               return DEFAULT_PRIORITY_LOCAL_FIRST + i;
+       }
+
+       return -1;
 }
 
-static int default_option_priority(struct discover_boot_option *opt)
+/*
+ * We have different priorities to resolve conflicts between boot options that
+ * report to be the default for their device. This function assigns a priority
+ * for these options.
+ */
+static enum default_priority default_option_priority(
+               struct discover_boot_option *opt)
 {
        const struct config *config;
-       struct boot_priority *prio;
-       int i;
 
        config = config_get();
 
-       for (i = 0; i < config->n_boot_priorities; i++) {
-               prio = &config->boot_priorities[i];
-               if (priority_match(prio, opt))
-                       break;
+       /* We give highest priority to IPMI-configured boot options. If
+        * we have an IPMI bootdev configuration set, then we don't allow
+        * any other defaults */
+       if (config->ipmi_bootdev) {
+               bool ipmi_match = ipmi_device_type_matches(config->ipmi_bootdev,
+                               opt->device->device->type);
+               if (ipmi_match)
+                       return DEFAULT_PRIORITY_REMOTE;
+
+               pb_debug("handler: disabled default priority due to "
+                               "non-matching IPMI type %x\n",
+                               config->ipmi_bootdev);
+               return DEFAULT_PRIORITY_DISABLED;
        }
 
-       return i;
+       /* Next, try to match the option against the user-defined autoboot
+        * options, either by device UUID or type. */
+       if (config->n_autoboot_opts) {
+               int boot_match = autoboot_option_priority(config, opt);
+               if (boot_match > 0)
+                       return boot_match;
+       }
+
+       /* If the option didn't match any entry in the array, it is disabled */
+       pb_debug("handler: disabled default priority due to "
+                       "non-matching UUID or type\n");
+       return DEFAULT_PRIORITY_DISABLED;
 }
 
 static void set_default(struct device_handler *handler,
                struct discover_boot_option *opt)
 {
+       enum default_priority cur_prio, new_prio;
+
        if (!handler->autoboot_enabled)
                return;
 
+       pb_debug("handler: new default option: %s\n", opt->option->id);
+
+       new_prio = default_option_priority(opt);
+
+       /* Anything outside our range prevents a default boot */
+       if (new_prio >= DEFAULT_PRIORITY_DISABLED)
+               return;
+
+       pb_debug("handler: calculated priority %d\n", new_prio);
+
        /* Resolve any conflicts: if we have a new default option, it only
         * replaces the current if it has a higher priority. */
        if (handler->default_boot_option) {
-               int new_prio, cur_prio;
 
-               new_prio = default_option_priority(opt);
-               cur_prio = default_option_priority(
-                                       handler->default_boot_option);
+               cur_prio = handler->default_boot_option_priority;
 
                if (new_prio < cur_prio) {
+                       pb_log("handler: new prio %d beats "
+                                       "old prio %d for %s\n",
+                                       new_prio, cur_prio,
+                                       handler->default_boot_option
+                                               ->option->id);
                        handler->default_boot_option = opt;
+                       handler->default_boot_option_priority = new_prio;
                        /* extend the timeout a little, so the user sees some
                         * indication of the change */
                        handler->sec_to_boot += 2;
@@ -408,8 +580,9 @@ static void set_default(struct device_handler *handler,
 
        handler->sec_to_boot = config_get()->autoboot_timeout_sec;
        handler->default_boot_option = opt;
+       handler->default_boot_option_priority = new_prio;
 
-       pb_log("Boot option %s set as default, timeout %u sec.\n",
+       pb_log("handler: boot option %s set as default, timeout %u sec.\n",
               opt->option->id, handler->sec_to_boot);
 
        default_timeout(handler);
@@ -526,6 +699,7 @@ struct discover_context *device_handler_discover_context_create(
 
        ctx = talloc_zero(handler, struct discover_context);
        ctx->device = device;
+       ctx->network = handler->network;
        list_init(&ctx->boot_options);
 
        return ctx;
@@ -583,17 +757,122 @@ void device_handler_add_device(struct device_handler *handler,
                                struct discover_device *, handler->n_devices);
        handler->devices[handler->n_devices - 1] = device;
 
+       if (device->device->type == DEVICE_TYPE_NETWORK)
+               network_register_device(handler->network, device);
+}
+
+void device_handler_add_ramdisk(struct device_handler *handler,
+               const char *path)
+{
+       struct ramdisk_device *dev;
+       unsigned int i;
+
+       if (!path)
+               return;
+
+       for (i = 0; i < handler->n_ramdisks; i++)
+               if (!strcmp(handler->ramdisks[i]->path, path))
+                       return;
+
+       dev = talloc_zero(handler, struct ramdisk_device);
+       if (!dev) {
+               pb_log("Failed to allocate memory to track %s\n", path);
+               return;
+       }
+
+       dev->path = talloc_strdup(handler, path);
+
+       handler->ramdisks = talloc_realloc(handler, handler->ramdisks,
+                               struct ramdisk_device *,
+                               handler->n_ramdisks + 1);
+       if (!handler->ramdisks) {
+               pb_log("Failed to reallocate memory"
+                      "- ramdisk tracking inconsistent!\n");
+               return;
+       }
+
+       handler->ramdisks[i] = dev;
+       i = handler->n_ramdisks++;
+}
+
+struct ramdisk_device *device_handler_get_ramdisk(
+               struct device_handler *handler)
+{
+       unsigned int i;
+       char *name;
+       dev_t id;
+
+       /* Check if free ramdisk exists */
+       for (i = 0; i < handler->n_ramdisks; i++)
+               if (!handler->ramdisks[i]->snapshot &&
+                   !handler->ramdisks[i]->origin &&
+                   !handler->ramdisks[i]->base)
+                       return handler->ramdisks[i];
+
+       /* Otherwise create a new one */
+       name = talloc_asprintf(handler, "/dev/ram%d",
+                       handler->n_ramdisks);
+       if (!name) {
+               pb_debug("Failed to allocate memory to name /dev/ram%d",
+                       handler->n_ramdisks);
+               return NULL;
+       }
+
+       id = makedev(1, handler->n_ramdisks);
+       if (mknod(name, S_IFBLK, id)) {
+               if (errno == EEXIST) {
+                       /* We haven't yet received updates for existing
+                        * ramdisks - add and use this one */
+                       pb_debug("Using untracked ramdisk %s\n", name);
+               } else {
+                       pb_log("Failed to create new ramdisk %s: %s\n",
+                              name, strerror(errno));
+                       return NULL;
+               }
+       }
+       device_handler_add_ramdisk(handler, name);
+       talloc_free(name);
+
+       return handler->ramdisks[i];
+}
+
+void device_handler_release_ramdisk(struct discover_device *device)
+{
+       struct ramdisk_device *ramdisk = device->ramdisk;
+
+       talloc_free(ramdisk->snapshot);
+       talloc_free(ramdisk->origin);
+       talloc_free(ramdisk->base);
+
+       ramdisk->snapshot = ramdisk->origin = ramdisk->base = NULL;
+       ramdisk->sectors = 0;
+
+       device->ramdisk = NULL;
 }
 
 /* Start discovery on a hotplugged device. The device will be in our devices
  * array, but has only just been initialised by the hotplug source.
  */
 int device_handler_discover(struct device_handler *handler,
-               struct discover_device *dev, enum conf_method method)
+               struct discover_device *dev)
 {
        struct discover_context *ctx;
+       struct boot_status *status;
        int rc;
 
+       status = talloc_zero(handler, struct boot_status);
+       status->type = BOOT_STATUS_INFO;
+       /*
+        * TRANSLATORS: this string will be passed the type and identifier
+        * of the device. For example, the first parameter could be "Disk",
+        * (which will be translated accordingly) and the second a Linux device
+        * identifier like 'sda1' (which will not be translated)
+        */
+       status->message = talloc_asprintf(status, _("Processing %s device %s"),
+                               device_type_display_name(dev->device->type),
+                               dev->device->id);
+       boot_status(handler, status);
+
        process_boot_option_queue(handler);
 
        /* create our context */
@@ -603,13 +882,65 @@ int device_handler_discover(struct device_handler *handler,
        if (rc)
                goto out;
 
+       /* add this device to our system info */
+       system_info_register_blockdev(dev->device->id, dev->uuid,
+                       dev->mount_path);
+
        /* run the parsers. This will populate the ctx's boot_option list. */
-       iterate_parsers(ctx, method);
+       iterate_parsers(ctx);
 
        /* add discovered stuff to the handler */
        device_handler_discover_context_commit(handler, ctx);
 
 out:
+       /*
+        * TRANSLATORS: the format specifier in this string is a Linux
+        * device identifier, like 'sda1'
+        */
+       status->message = talloc_asprintf(status,_("Processing %s complete"),
+                               dev->device->id);
+       boot_status(handler, status);
+
+       talloc_free(status);
+       talloc_free(ctx);
+
+       return 0;
+}
+
+/* Incoming dhcp event */
+int device_handler_dhcp(struct device_handler *handler,
+               struct discover_device *dev, struct event *event)
+{
+       struct discover_context *ctx;
+       struct boot_status *status;
+
+       status = talloc_zero(handler, struct boot_status);
+       status->type = BOOT_STATUS_INFO;
+       /*
+        * TRANSLATORS: this format specifier will be the name of a network
+        * device, like 'eth0'.
+        */
+       status->message = talloc_asprintf(status, _("Processing dhcp event on %s"),
+                               dev->device->id);
+       boot_status(handler, status);
+
+       /* create our context */
+       ctx = device_handler_discover_context_create(handler, dev);
+       ctx->event = event;
+
+       iterate_parsers(ctx);
+
+       device_handler_discover_context_commit(handler, ctx);
+
+       /*
+        * TRANSLATORS: this format specifier will be the name of a network
+        * device, like 'eth0'.
+        */
+       status->message = talloc_asprintf(status,_("Processing %s complete"),
+                               dev->device->id);
+       boot_status(handler, status);
+
+       talloc_free(status);
        talloc_free(ctx);
 
        return 0;
@@ -617,19 +948,29 @@ out:
 
 /* incoming conf event */
 int device_handler_conf(struct device_handler *handler,
-               struct discover_device *dev, struct pb_url *url,
-               enum conf_method method)
+               struct discover_device *dev, struct pb_url *url)
 {
        struct discover_context *ctx;
+       struct boot_status *status;
+
+       status = talloc_zero(handler, struct boot_status);
+       status->type = BOOT_STATUS_INFO;
+       status->message = talloc_asprintf(status, _("Processing user config"));
+       boot_status(handler, status);
 
        /* create our context */
        ctx = device_handler_discover_context_create(handler, dev);
        ctx->conf_url = url;
 
-       iterate_parsers(ctx, method);
+       iterate_parsers(ctx);
 
        device_handler_discover_context_commit(handler, ctx);
 
+       status->message = talloc_asprintf(status,
+                               _("Processing user config complete"));
+       boot_status(handler, status);
+
+       talloc_free(status);
        talloc_free(ctx);
 
        return 0;
@@ -662,6 +1003,9 @@ void device_handler_boot(struct device_handler *handler,
 
        if (handler->pending_boot)
                boot_cancel(handler->pending_boot);
+
+       platform_pre_boot();
+
        handler->pending_boot = boot(handler, opt, cmd, handler->dry_run,
                        boot_status, handler);
        handler->pending_boot_is_default = false;
@@ -694,20 +1038,264 @@ void device_handler_cancel_default(struct device_handler *handler)
        status.type = BOOT_STATUS_INFO;
        status.progress = -1;
        status.detail = NULL;
-       status.message = "Default boot cancelled";
+       status.message = _("Default boot cancelled");
 
        discover_server_notify_boot_status(handler->server, &status);
 }
 
+void device_handler_update_config(struct device_handler *handler,
+               struct config *config)
+{
+       int rc;
+
+       rc = config_set(config);
+       if (rc)
+               return;
+
+       discover_server_notify_config(handler->server, config);
+       device_handler_update_lang(config->lang);
+       device_handler_reinit(handler);
+}
+
+static char *device_from_addr(void *ctx, struct pb_url *url)
+{
+       char *ipaddr, *buf, *tok, *dev = NULL;
+       const char *delim = " ";
+       struct sockaddr_in *ip;
+       struct sockaddr_in si;
+       struct addrinfo *res;
+       struct process *p;
+       int rc;
+
+       /* Note: IPv4 only */
+       rc = inet_pton(AF_INET, url->host, &(si.sin_addr));
+       if (rc > 0) {
+               ipaddr = url->host;
+       } else {
+               /* need to turn hostname into a valid IP */
+               rc = getaddrinfo(url->host, NULL, NULL, &res);
+               if (rc) {
+                       pb_debug("%s: Invalid URL\n",__func__);
+                       return NULL;
+               }
+               ipaddr = talloc_array(ctx,char,INET_ADDRSTRLEN);
+               ip = (struct sockaddr_in *) res->ai_addr;
+               inet_ntop(AF_INET, &(ip->sin_addr), ipaddr, INET_ADDRSTRLEN);
+               freeaddrinfo(res);
+       }
+
+       const char *argv[] = {
+               pb_system_apps.ip,
+               "route", "show", "to", "match",
+               ipaddr,
+               NULL
+       };
+
+       p = process_create(ctx);
+
+       p->path = pb_system_apps.ip;
+       p->argv = argv;
+       p->keep_stdout = true;
+
+       rc = process_run_sync(p);
+
+       if (rc) {
+               /* ip has complained for some reason; most likely
+                * there is no route to the host - bail out */
+               pb_debug("%s: No route to %s\n",__func__,url->host);
+               return NULL;
+       }
+
+       buf = p->stdout_buf;
+       /* If a route is found, ip-route output will be of the form
+        * "... dev DEVNAME ... " */
+       tok = strtok(buf, delim);
+       while (tok) {
+               if (!strcmp(tok, "dev")) {
+                       tok = strtok(NULL, delim);
+                       dev = talloc_strdup(ctx, tok);
+                       break;
+               }
+               tok = strtok(NULL, delim);
+       }
+
+       process_release(p);
+       if (dev)
+               pb_debug("%s: Found interface '%s'\n", __func__,dev);
+       return dev;
+}
+
+void device_handler_process_url(struct device_handler *handler,
+               const char *url, const char *mac, const char *ip)
+{
+       struct discover_context *ctx;
+       struct discover_device *dev;
+       struct boot_status *status;
+       struct pb_url *pb_url;
+       struct event *event;
+       struct param *param;
+
+       status = talloc(handler, struct boot_status);
+
+       status->type = BOOT_STATUS_ERROR;
+       status->progress = 0;
+       status->detail = talloc_asprintf(status,
+                       _("Received config URL %s"), url);
+
+       if (!handler->network) {
+               status->message = talloc_asprintf(handler,
+                                       _("No network configured"));
+               goto msg;
+       }
+
+       event = talloc(handler, struct event);
+       event->type = EVENT_TYPE_USER;
+       event->action = EVENT_ACTION_CONF;
+
+       if (url[strlen(url) - 1] == '/') {
+               event->params = talloc_array(event, struct param, 3);
+               param = &event->params[0];
+               param->name = talloc_strdup(event, "pxepathprefix");
+               param->value = talloc_strdup(event, url);
+               param = &event->params[1];
+               param->name = talloc_strdup(event, "mac");
+               param->value = talloc_strdup(event, mac);
+               param = &event->params[2];
+               param->name = talloc_strdup(event, "ip");
+               param->value = talloc_strdup(event, ip);
+               event->n_params = 3;
+       } else {
+               event->params = talloc_array(event, struct param, 1);
+               param = &event->params[0];
+               param->name = talloc_strdup(event, "pxeconffile");
+               param->value = talloc_strdup(event, url);
+               event->n_params = 1;
+       }
+
+       pb_url = pb_url_parse(event, event->params->value);
+       if (!pb_url || !pb_url->host) {
+               status->message = talloc_asprintf(handler,
+                                       _("Invalid config URL!"));
+               goto msg;
+       }
+
+       event->device = device_from_addr(event, pb_url);
+       if (!event->device) {
+               status->message = talloc_asprintf(status,
+                                       _("Unable to route to host %s"),
+                                       pb_url->host);
+               goto msg;
+       }
+
+       dev = discover_device_create(handler, event->device);
+       ctx = device_handler_discover_context_create(handler, dev);
+       ctx->event = event;
+
+       iterate_parsers(ctx);
+
+       device_handler_discover_context_commit(handler, ctx);
+
+       talloc_free(ctx);
+
+       status->type = BOOT_STATUS_INFO;
+       status->message = talloc_asprintf(status, _("Config file %s parsed"),
+                                       pb_url->file);
+msg:
+       boot_status(handler, status);
+       talloc_free(status);
+}
+
 #ifndef PETITBOOT_TEST
+
+static void device_handler_update_lang(const char *lang)
+{
+       const char *cur_lang;
+
+       if (!lang)
+               return;
+
+       cur_lang = setlocale(LC_ALL, NULL);
+       if (cur_lang && !strcmp(cur_lang, lang))
+               return;
+
+       setlocale(LC_ALL, lang);
+}
+
+static int device_handler_init_sources(struct device_handler *handler)
+{
+       /* init our device sources: udev, network and user events */
+       handler->udev = udev_init(handler, handler->waitset);
+       if (!handler->udev)
+               return -1;
+
+       handler->network = network_init(handler, handler->waitset,
+                       handler->dry_run);
+       if (!handler->network)
+               return -1;
+
+       handler->user_event = user_event_init(handler, handler->waitset);
+       if (!handler->user_event)
+               return -1;
+
+       return 0;
+}
+
+static void device_handler_reinit_sources(struct device_handler *handler)
+{
+       /* if we haven't initialised sources previously (becuase we started in
+        * safe mode), then init once here. */
+       if (!(handler->udev || handler->network || handler->user_event)) {
+               device_handler_init_sources(handler);
+               return;
+       }
+
+       udev_reinit(handler->udev);
+
+       network_shutdown(handler->network);
+       handler->network = network_init(handler, handler->waitset,
+                       handler->dry_run);
+}
+
+static const char *fs_parameters(struct discover_device *dev,
+                                unsigned int rw_flags)
+{
+       const char *fstype = discover_device_get_param(dev, "ID_FS_TYPE");
+
+       /* XFS journals are not cross-endian compatible; don't try recovery
+        * even if we have a snapshot */
+       if (!strncmp(fstype, "xfs", strlen("xfs")))
+               return "norecovery";
+
+       /* If we have a snapshot available allow touching the filesystem */
+       if (dev->ramdisk)
+               return "";
+
+       if ((rw_flags | MS_RDONLY) != MS_RDONLY)
+               return "";
+
+       /* Avoid writes due to journal replay if we don't have a snapshot */
+       if (!strncmp(fstype, "ext4", strlen("ext4")))
+               return "norecovery";
+
+       return "";
+}
+
+static inline const char *get_device_path(struct discover_device *dev)
+{
+       return dev->ramdisk ? dev->ramdisk->snapshot : dev->device_path;
+}
+
 static bool check_existing_mount(struct discover_device *dev)
 {
        struct stat devstat, mntstat;
+       const char *device_path;
        struct mntent *mnt;
        FILE *fp;
        int rc;
 
-       rc = stat(dev->device_path, &devstat);
+       device_path = get_device_path(dev);
+
+       rc = stat(device_path, &devstat);
        if (rc) {
                pb_debug("%s: stat failed: %s\n", __func__, strerror(errno));
                return false;
@@ -757,6 +1345,7 @@ static bool check_existing_mount(struct discover_device *dev)
 
 static int mount_device(struct discover_device *dev)
 {
+       const char *fstype, *device_path;
        int rc;
 
        if (!dev->device_path)
@@ -768,6 +1357,17 @@ static int mount_device(struct discover_device *dev)
        if (check_existing_mount(dev))
                return 0;
 
+       fstype = discover_device_get_param(dev, "ID_FS_TYPE");
+       if (!fstype)
+               return 0;
+
+       /* ext3 treats the norecovery option as an error, so mount the device
+        * as an ext4 filesystem instead */
+       if (!strncmp(fstype, "ext3", strlen("ext3"))) {
+               pb_debug("Mounting ext3 filesystem as ext4\n");
+               fstype = talloc_asprintf(dev, "ext4");
+       }
+
        dev->mount_path = join_paths(dev, mount_base(),
                                        dev->device_path);
 
@@ -777,9 +1377,13 @@ static int mount_device(struct discover_device *dev)
                goto err_free;
        }
 
-       rc = process_run_simple(dev, pb_system_apps.mount,
-                       dev->device_path, dev->mount_path,
-                       "-o", "ro", NULL);
+       device_path = get_device_path(dev);
+
+       pb_log("mounting device %s read-only\n", dev->device_path);
+       errno = 0;
+       rc = mount(device_path, dev->mount_path, fstype,
+                       MS_RDONLY | MS_SILENT,
+                       fs_parameters(dev, MS_RDONLY));
        if (!rc) {
                dev->mounted = true;
                dev->mounted_rw = false;
@@ -787,16 +1391,11 @@ static int mount_device(struct discover_device *dev)
                return 0;
        }
 
-       /* Retry mount without ro option. */
-       rc = process_run_simple(dev, pb_system_apps.mount,
-                       dev->device_path, dev->mount_path, NULL);
+       pb_log("couldn't mount device %s: mount failed: %s\n",
+                       device_path, strerror(errno));
 
-       if (!rc) {
-               dev->mounted = true;
-               dev->mounted_rw = true;
-               dev->unmount = true;
-               return 0;
-       }
+       /* If mount fails clean up any snapshot */
+       devmapper_destroy_snapshot(dev);
 
        pb_rmdir_recursive(mount_base(), dev->mount_path);
 err_free:
@@ -807,18 +1406,21 @@ err_free:
 
 static int umount_device(struct discover_device *dev)
 {
-       int status;
+       const char *device_path;
+       int rc;
 
        if (!dev->mounted || !dev->unmount)
                return 0;
 
-       status = process_run_simple(dev, pb_system_apps.umount,
-                       dev->mount_path, NULL);
+       device_path = get_device_path(dev);
 
-       if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
+       pb_log("unmounting device %s\n", device_path);
+       rc = umount(dev->mount_path);
+       if (rc)
                return -1;
 
        dev->mounted = false;
+       devmapper_destroy_snapshot(dev);
 
        pb_rmdir_recursive(mount_base(), dev->mount_path);
 
@@ -830,38 +1432,107 @@ static int umount_device(struct discover_device *dev)
 
 int device_request_write(struct discover_device *dev, bool *release)
 {
+       const char *fstype, *device_path;
+       const struct config *config;
        int rc;
 
        *release = false;
 
+       config = config_get();
+       if (!config->allow_writes)
+               return -1;
+
        if (!dev->mounted)
                return -1;
 
        if (dev->mounted_rw)
                return 0;
 
-       rc = process_run_simple(dev, pb_system_apps.mount, dev->mount_path,
-                       "-o", "remount,rw", NULL);
-       if (rc)
+       fstype = discover_device_get_param(dev, "ID_FS_TYPE");
+
+       device_path = get_device_path(dev);
+
+       pb_log("remounting device %s read-write\n", device_path);
+
+       rc = umount(dev->mount_path);
+       if (rc) {
+               pb_log("Failed to unmount %s: %s\n",
+                      dev->mount_path, strerror(errno));
                return -1;
+       }
+
+       rc = mount(device_path, dev->mount_path, fstype,
+                       MS_SILENT,
+                       fs_parameters(dev, MS_REMOUNT));
+       if (rc)
+               goto mount_ro;
 
        dev->mounted_rw = true;
        *release = true;
        return 0;
+
+mount_ro:
+       pb_log("Unable to remount device %s read-write: %s\n",
+              device_path, strerror(errno));
+       if (mount(device_path, dev->mount_path, fstype,
+                       MS_RDONLY | MS_SILENT,
+                       fs_parameters(dev, MS_RDONLY)))
+               pb_log("Unable to recover mount for %s: %s\n",
+                      device_path, strerror(errno));
+       return -1;
 }
 
 void device_release_write(struct discover_device *dev, bool release)
 {
+       const char *fstype, *device_path;
+
        if (!release)
                return;
 
-       process_run_simple(dev, pb_system_apps.mount, dev->mount_path,
-                       "-o", "remount,ro", NULL);
-       dev->mounted_rw = false;
+       device_path = get_device_path(dev);
+
+       fstype = discover_device_get_param(dev, "ID_FS_TYPE");
+
+       pb_log("remounting device %s read-only\n", device_path);
+
+       if (umount(dev->mount_path)) {
+               pb_log("Failed to unmount %s\n", dev->mount_path);
+               return;
+       }
+       dev->mounted_rw = dev->mounted = false;
+
+       if (dev->ramdisk) {
+               devmapper_merge_snapshot(dev);
+               /* device_path becomes stale after merge */
+               device_path = get_device_path(dev);
+       }
+
+       if (mount(device_path, dev->mount_path, fstype,
+                       MS_RDONLY | MS_SILENT,
+                       fs_parameters(dev, MS_RDONLY)))
+               pb_log("Failed to remount %s read-only: %s\n",
+                      device_path, strerror(errno));
+       else
+               dev->mounted = true;
 }
 
 #else
 
+static void device_handler_update_lang(const char *lang __attribute__((unused)))
+{
+}
+
+static int device_handler_init_sources(
+               struct device_handler *handler __attribute__((unused)))
+{
+       return 0;
+}
+
+static void device_handler_reinit_sources(
+               struct device_handler *handler __attribute__((unused)))
+{
+}
+
 static int umount_device(struct discover_device *dev __attribute__((unused)))
 {
        return 0;