path: root/e-util/e-passwords.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */

/*
 * e-passwords.c
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 */

/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU Lesser General Public
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
 * USA.
 */

/*
 * This looks a lot more complicated than it is, and than you'd think
 * it would need to be.  There is however, method to the madness.
 *
 * The code must cope with being called from any thread at any time,
 * recursively from the main thread, and then serialising every
 * request so that sane and correct values are always returned, and
 * duplicate requests are never made.
 *
 * To this end, every call is marshalled and queued and a dispatch
 * method invoked until that request is satisfied.  If mainloop
 * recursion occurs, then the sub-call will necessarily return out of
 * order, but will not be processed out of order.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <gtk/gtk.h>
#include <glib/gi18n-lib.h>

/* XXX Yeah, yeah... */
#define SECRET_API_SUBJECT_TO_CHANGE

#include <libsecret/secret.h>

#include <libedataserver/libedataserver.h>

#include "e-passwords.h"

#define d(x)

typedef struct _EPassMsg EPassMsg;

struct _EPassMsg {
    void (*dispatch) (EPassMsg *);
    EFlag *done;

    /* input */
    GtkWindow *parent;
    const gchar *key;
    const gchar *title;
    const gchar *prompt;
    const gchar *oldpass;
    guint32 flags;

    /* output */
    gboolean *remember;
    gchar *password;
    GError *error;

    /* work variables */
    GtkWidget *entry;
    GtkWidget *check;
    guint ismain : 1;
    guint noreply:1;    /* supress replies; when calling
                 * dispatch functions from others */
};

/* XXX probably want to share this with evalution-source-registry-migrate-sources.c */
static const SecretSchema e_passwords_schema = {
    "org.gnome.Evolution.Password",
    SECRET_SCHEMA_DONT_MATCH_NAME,
    {
        { "application", SECRET_SCHEMA_ATTRIBUTE_STRING, },
        { "user", SECRET_SCHEMA_ATTRIBUTE_STRING, },
        { "server", SECRET_SCHEMA_ATTRIBUTE_STRING, },
        { "protocol", SECRET_SCHEMA_ATTRIBUTE_STRING, },
    }
};

G_LOCK_DEFINE_STATIC (passwords);
static GThread *main_thread = NULL;
static GHashTable *password_cache = NULL;
static GtkDialog *password_dialog = NULL;
static GQueue message_queue = G_QUEUE_INIT;
static gint idle_id;
static gint ep_online_state = TRUE;

static EUri *
ep_keyring_uri_new (const gchar *string,
                    GError **error)
{
    EUri *uri;

    uri = e_uri_new (string);
    g_return_val_if_fail (uri != NULL, NULL);

    /* LDAP URIs do not have usernames, so use the URI as the username. */
    if (uri->user == NULL && uri->protocol != NULL &&
            (strcmp (uri->protocol, "ldap") == 0|| strcmp (uri->protocol, "google") == 0))
        uri->user = g_strdelimit (g_strdup (string), "/=", '_');

    /* Make sure the URI has the required components. */
    if (uri->user == NULL && uri->host == NULL) {
        g_set_error_literal (
            error, G_IO_ERROR,
            G_IO_ERROR_INVALID_ARGUMENT,
            _("Keyring key is unusable: no user or host name"));
        e_uri_free (uri);
        uri = NULL;
    }

    return uri;
}

static gboolean
ep_idle_dispatch (gpointer data)
{
    EPassMsg *msg;

    /* As soon as a password window is up we stop; it will
     * re - invoke us when it has been closed down */
    G_LOCK (passwords);
    while (password_dialog == NULL && (msg = g_queue_pop_head (&message_queue)) != NULL) {
        G_UNLOCK (passwords);

        msg->dispatch (msg);

        G_LOCK (passwords);
    }

    idle_id = 0;
    G_UNLOCK (passwords);

    return FALSE;
}

static EPassMsg *
ep_msg_new (void (*dispatch) (EPassMsg *))
{
    EPassMsg *msg;

    e_passwords_init ();

    msg = g_malloc0 (sizeof (*msg));
    msg->dispatch = dispatch;
    msg->done = e_flag_new ();
    msg->ismain = (g_thread_self () == main_thread);

    return msg;
}

static void
ep_msg_free (EPassMsg *msg)
{
    /* XXX We really should be passing this back to the caller, but
     *     doing so will require breaking the password API. */
    if (msg->error != NULL) {
        g_warning ("%s", msg->error->message);
        g_error_free (msg->error);
    }

    e_flag_free (msg->done);
    g_free (msg->password);
    g_free (msg);
}

static void
ep_msg_send (EPassMsg *msg)
{
    gint needidle = 0;

    G_LOCK (passwords);
    g_queue_push_tail (&message_queue, msg);
    if (!idle_id) {
        if (!msg->ismain)
            idle_id = g_idle_add (ep_idle_dispatch, NULL);
        else
            needidle = 1;
    }
    G_UNLOCK (passwords);

    if (msg->ismain) {
        if (needidle)
            ep_idle_dispatch (NULL);
        while (!e_flag_is_set (msg->done))
            g_main_context_iteration (NULL, TRUE);
    } else
        e_flag_wait (msg->done);
}

/* the functions that actually do the work */

static void
ep_remember_password (EPassMsg *msg)
{
    gchar *password;
    EUri *uri;
    GError *error = NULL;

    password = g_hash_table_lookup (password_cache, msg->key);
    if (password == NULL) {
        g_warning ("Password for key \"%s\" not found", msg->key);
        goto exit;
    }

    uri = ep_keyring_uri_new (msg->key, &msg->error);
    if (uri == NULL)
        goto exit;

    secret_password_store_sync (
        &e_passwords_schema,
        SECRET_COLLECTION_DEFAULT,
        msg->key, password,
        NULL, &error,
        "application", "Evolution",
        "user", uri->user,
        "server", uri->host,
        "protocol", uri->protocol,
        NULL);

    /* Only remove the password from the session hash
     * if the keyring insertion was successful. */
    if (error == NULL)
        g_hash_table_remove (password_cache, msg->key);
    else
        g_propagate_error (&msg->error, error);

    e_uri_free (uri);

exit:
    if (!msg->noreply)
        e_flag_set (msg->done);
}

static void
ep_forget_password (EPassMsg *msg)
{
    EUri *uri;
    GError *error = NULL;

    g_hash_table_remove (password_cache, msg->key);

    uri = ep_keyring_uri_new (msg->key, &msg->error);
    if (uri == NULL)
        goto exit;

    /* Find all Evolution passwords matching the URI and delete them.
     *
     * XXX We didn't always store protocols in the keyring, so for
     *     backward-compatibility we need to lookup passwords by user
     *     and host only (no protocol).  But we do send the protocol
     *     to ep_keyring_delete_passwords(), which also knows about
     *     the backward-compatibility issue and will filter the list
     *     appropriately. */
    secret_password_clear_sync (
        &e_passwords_schema, NULL, &error,
        "application", "Evolution",
        "user", uri->user,
        "server", uri->host,
        NULL);

    if (error != NULL)
        g_propagate_error (&msg->error, error);

    e_uri_free (uri);

exit:
    if (!msg->noreply)
        e_flag_set (msg->done);
}

static void
ep_get_password (EPassMsg *msg)
{
    EUri *uri;
    gchar *password;
    GError *error = NULL;

    /* Check the in-memory cache first. */
    password = g_hash_table_lookup (password_cache, msg->key);
    if (password != NULL) {
        msg->password = g_strdup (password);
        goto exit;
    }

    uri = ep_keyring_uri_new (msg->key, &msg->error);
    if (uri == NULL)
        goto exit;

    msg->password = secret_password_lookup_sync (
        &e_passwords_schema, NULL, &error,
        "application", "Evolution",
        "user", uri->user,
        "server", uri->host,
        "protocol", uri->protocol,
        NULL);

    if (msg->password != NULL)
        goto done;

    /* Clear the previous error, if there was one.
     * It's likely to occur again. */
    if (error != NULL)
        g_clear_error (&error);

    /* XXX We didn't always store protocols in the keyring, so for
     *     backward-compatibility we also need to lookup passwords
     *     by user and host only (no protocol). */
    msg->password = secret_password_lookup_sync (
        &e_passwords_schema, NULL, &error,
        "application", "Evolution",
        "user", uri->user,
        "server", uri->host,
        NULL);

done:
    if (error != NULL)
        g_propagate_error (&msg->error, error);

    e_uri_free (uri);

exit:
    if (!msg->noreply)
        e_flag_set (msg->done);
}

static void
ep_add_password (EPassMsg *msg)
{
    g_hash_table_insert (
        password_cache, g_strdup (msg->key),
        g_strdup (msg->oldpass));

    if (!msg->noreply)
        e_flag_set (msg->done);
}

static void ep_ask_password (EPassMsg *msg);

static void
pass_response (GtkDialog *dialog,
               gint response,
               gpointer data)
{
    EPassMsg *msg = data;
    gint type = msg->flags & E_PASSWORDS_REMEMBER_MASK;
    GList *iter, *trash = NULL;

    if (response == GTK_RESPONSE_OK) {
        msg->password = g_strdup (gtk_entry_get_text ((GtkEntry *) msg->entry));

        if (type != E_PASSWORDS_REMEMBER_NEVER) {
            gint noreply = msg->noreply;

            *msg->remember = gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (msg->check));

            msg->noreply = 1;

            if (*msg->remember || type == E_PASSWORDS_REMEMBER_FOREVER) {
                msg->oldpass = msg->password;
                ep_add_password (msg);
            }
            if (*msg->remember && type == E_PASSWORDS_REMEMBER_FOREVER)
                ep_remember_password (msg);

            msg->noreply = noreply;
        }
    }

    gtk_widget_destroy ((GtkWidget *) dialog);
    password_dialog = NULL;

    /* ok, here things get interesting, we suck up any pending
     * operations on this specific password, and return the same
     * result or ignore other operations */

    G_LOCK (passwords);
    for (iter = g_queue_peek_head_link (&message_queue); iter != NULL; iter = iter->next) {
        EPassMsg *pending = iter->data;

        if ((pending->dispatch == ep_forget_password
             || pending->dispatch == ep_get_password
             || pending->dispatch == ep_ask_password)
            && strcmp (pending->key, msg->key) == 0) {

            /* Satisfy the pending operation. */
            pending->password = g_strdup (msg->password);
            e_flag_set (pending->done);

            /* Mark the queue node for deletion. */
            trash = g_list_prepend (trash, iter);
        }
    }

    /* Expunge the message queue. */
    for (iter = trash; iter != NULL; iter = iter->next)
        g_queue_delete_link (&message_queue, iter->data);
    g_list_free (trash);

    G_UNLOCK (passwords);

    if (!msg->noreply)
        e_flag_set (msg->done);

    ep_idle_dispatch (NULL);
}

static gboolean
update_capslock_state (GtkDialog *dialog,
                       GdkEvent *event,
                       GtkWidget *label)
{
    GdkModifierType mask = 0;
    GdkWindow *window;
    gchar *markup = NULL;
    GdkDeviceManager *device_manager;
    GdkDevice *device;

    device_manager = gdk_display_get_device_manager (gtk_widget_get_display (label));
    device = gdk_device_manager_get_client_pointer (device_manager);
    window = gtk_widget_get_window (GTK_WIDGET (dialog));
    gdk_window_get_device_position (window, device, NULL, NULL, &mask);

    /* The space acts as a vertical placeholder. */
    markup = g_markup_printf_escaped (
        "<small>%s</small>", (mask & GDK_LOCK_MASK) ?
        _("You have the Caps Lock key on.") : " ");
    gtk_label_set_markup (GTK_LABEL (label), markup);
    g_free (markup);

    return FALSE;
}

static void
ep_ask_password (EPassMsg *msg)
{
    GtkWidget *widget;
    GtkWidget *container;
    GtkWidget *action_area;
    GtkWidget *content_area;
    gint type = msg->flags & E_PASSWORDS_REMEMBER_MASK;
    guint noreply = msg->noreply;
    gboolean visible;
    AtkObject *a11y;

    msg->noreply = 1;

    widget = gtk_dialog_new_with_buttons (
        msg->title, msg->parent, 0,
        GTK_STOCK_CANCEL, GTK_RESPONSE_CANCEL,
        GTK_STOCK_OK, GTK_RESPONSE_OK,
        NULL);
    gtk_dialog_set_default_response (
        GTK_DIALOG (widget), GTK_RESPONSE_OK);
    gtk_window_set_resizable (GTK_WINDOW (widget), FALSE);
    gtk_window_set_transient_for (GTK_WINDOW (widget), msg->parent);
    gtk_window_set_position (GTK_WINDOW (widget), GTK_WIN_POS_CENTER_ON_PARENT);
    gtk_container_set_border_width (GTK_CONTAINER (widget), 12);
    password_dialog = GTK_DIALOG (widget);

    action_area = gtk_dialog_get_action_area (password_dialog);
    content_area = gtk_dialog_get_content_area (password_dialog);

    /* Override GtkDialog defaults */
    gtk_box_set_spacing (GTK_BOX (action_area), 12);
    gtk_container_set_border_width (GTK_CONTAINER (action_area), 0);
    gtk_box_set_spacing (GTK_BOX (content_area), 12);
    gtk_container_set_border_width (GTK_CONTAINER (content_area), 0);

    /* Grid */
    container = gtk_grid_new ();
    gtk_grid_set_column_spacing (GTK_GRID (container), 12);
    gtk_grid_set_row_spacing (GTK_GRID (container), 6);
    gtk_widget_show (container);

    gtk_box_pack_start (
        GTK_BOX (content_area), container, FALSE, TRUE, 0);

    /* Password Image */
    widget = gtk_image_new_from_icon_name (
        "dialog-password", GTK_ICON_SIZE_DIALOG);
    gtk_misc_set_alignment (GTK_MISC (widget), 0.0, 0.0);
    g_object_set (
        G_OBJECT (widget),
        "halign", GTK_ALIGN_FILL,
        "vexpand", TRUE,
        "valign", GTK_ALIGN_FILL,
        NULL);
    gtk_widget_show (widget);

    gtk_grid_attach (GTK_GRID (container), widget, 0, 0, 1, 3);

    /* Password Label */
    widget = gtk_label_new (NULL);
    gtk_label_set_line_wrap (GTK_LABEL (widget), TRUE);
    gtk_label_set_markup (GTK_LABEL (widget), msg->prompt);
    gtk_misc_set_alignment (GTK_MISC (widget), 0.0, 0.5);
    g_object_set (
        G_OBJECT (widget),
        "hexpand", TRUE,
        "halign", GTK_ALIGN_FILL,
        NULL);
    gtk_widget_show (widget);

    gtk_grid_attach (GTK_GRID (container), widget, 1, 0, 1, 1);

    /* Password Entry */
    widget = gtk_entry_new ();
    a11y = gtk_widget_get_accessible (widget);
    visible = !(msg->flags & E_PASSWORDS_SECRET);
    atk_object_set_description (a11y, msg->prompt);
    gtk_entry_set_visibility (GTK_ENTRY (widget), visible);
    gtk_entry_set_activates_default (GTK_ENTRY (widget), TRUE);
    gtk_widget_grab_focus (widget);
    g_object_set (
        G_OBJECT (widget),
        "hexpand", TRUE,
        "halign", GTK_ALIGN_FILL,
        NULL);
    gtk_widget_show (widget);
    msg->entry = widget;

    if ((msg->flags & E_PASSWORDS_REPROMPT)) {
        ep_get_password (msg);
        if (msg->password != NULL) {
            gtk_entry_set_text (GTK_ENTRY (widget), msg->password);
            g_free (msg->password);
            msg->password = NULL;
        }
    }

    gtk_grid_attach (GTK_GRID (container), widget, 1, 1, 1, 1);

    /* Caps Lock Label */
    widget = gtk_label_new (NULL);
    g_object_set (
        G_OBJECT (widget),
        "hexpand", TRUE,
        "halign", GTK_ALIGN_FILL,
        NULL);
    gtk_widget_show (widget);

    gtk_grid_attach (GTK_GRID (container), widget, 1, 2, 1, 1);

    g_signal_connect (
        password_dialog, "key-release-event",
        G_CALLBACK (update_capslock_state), widget);
    g_signal_connect (
        password_dialog, "focus-in-event",
        G_CALLBACK (update_capslock_state), widget);

    /* static password, shouldn't be remembered between sessions,
     * but will be remembered within the session beyond our control */
    if (type != E_PASSWORDS_REMEMBER_NEVER) {
        if (msg->flags & E_PASSWORDS_PASSPHRASE) {
            widget = gtk_check_button_new_with_mnemonic (
                (type == E_PASSWORDS_REMEMBER_FOREVER)
                ? _("_Remember this passphrase")
                : _("_Remember this passphrase for"
                " the remainder of this session"));
        } else {
            widget = gtk_check_button_new_with_mnemonic (
                (type == E_PASSWORDS_REMEMBER_FOREVER)
                ? _("_Remember this password")
                : _("_Remember this password for"
                " the remainder of this session"));
        }

        gtk_toggle_button_set_active (
            GTK_TOGGLE_BUTTON (widget), *msg->remember);
        if (msg->flags & E_PASSWORDS_DISABLE_REMEMBER)
            gtk_widget_set_sensitive (widget, FALSE);
        g_object_set (
            G_OBJECT (widget),
            "hexpand", TRUE,
            "halign", GTK_ALIGN_FILL,
            "valign", GTK_ALIGN_FILL,
            NULL);
        gtk_widget_show (widget);
        msg->check = widget;

        gtk_grid_attach (GTK_GRID (container), widget, 1, 3, 1, 1);
    }

    msg->noreply = noreply;

    g_signal_connect (
        password_dialog, "response",
        G_CALLBACK (pass_response), msg);

    if (msg->parent) {
        gtk_dialog_run (GTK_DIALOG (password_dialog));
    } else {
        gtk_window_present (GTK_WINDOW (password_dialog));
        /* workaround GTK+ bug (see Gnome's bugzilla bug #624229) */
        gtk_grab_add (GTK_WIDGET (password_dialog));
    }
}

/**
 * e_passwords_init:
 *
 * Initializes the e_passwords routines. Must be called before any other
 * e_passwords_* function.
 **/
void
e_passwords_init (void)
{
    G_LOCK (passwords);

    if (password_cache == NULL) {
        password_cache = g_hash_table_new_full (
            g_str_hash, g_str_equal,
            (GDestroyNotify) g_free,
            (GDestroyNotify) g_free);
        main_thread = g_thread_self ();
    }

    G_UNLOCK (passwords);
}

/**
 * e_passwords_set_online:
 * @state:
 *
 * Set the offline-state of the application.  This is a work-around
 * for having the backends fully offline aware, and returns a
 * cancellation response instead of prompting for passwords.
 *
 * FIXME: This is not a permanent api, review post 2.0.
 **/
void
e_passwords_set_online (gint state)
{
    ep_online_state = state;
    /* TODO: we could check that a request is open and close it, or maybe who cares */
}

/**
 * e_passwords_remember_password:
 * @key: the key
 *
 * Saves the password associated with @key to disk.
 **/
void
e_passwords_remember_password (const gchar *key)
{
    EPassMsg *msg;

    g_return_if_fail (key != NULL);

    msg = ep_msg_new (ep_remember_password);
    msg->key = key;

    ep_msg_send (msg);
    ep_msg_free (msg);
}

/**
 * e_passwords_forget_password:
 * @key: the key
 *
 * Forgets the password associated with @key, in memory and on disk.
 **/
void
e_passwords_forget_password (const gchar *key)
{
    EPassMsg *msg;

    g_return_if_fail (key != NULL);

    msg = ep_msg_new (ep_forget_password);
    msg->key = key;

    ep_msg_send (msg);
    ep_msg_free (msg);
}

/**
 * e_passwords_get_password:
 * @key: the key
 *
 * Returns: the password associated with @key, or %NULL.  Caller
 * must free the returned password.
 **/
gchar *
e_passwords_get_password (const gchar *key)
{
    EPassMsg *msg;
    gchar *passwd;

    g_return_val_if_fail (key != NULL, NULL);

    msg = ep_msg_new (ep_get_password);
    msg->key = key;

    ep_msg_send (msg);

    passwd = msg->password;
    msg->password = NULL;
    ep_msg_free (msg);

    return passwd;
}

/**
 * e_passwords_add_password:
 * @key: a key
 * @passwd: the password for @key
 *
 * This stores the @key/@passwd pair in the current session's password
 * hash.
 **/
void
e_passwords_add_password (const gchar *key,
                          const gchar *passwd)
{
    EPassMsg *msg;

    g_return_if_fail (key != NULL);
    g_return_if_fail (passwd != NULL);

    msg = ep_msg_new (ep_add_password);
    msg->key = key;
    msg->oldpass = passwd;

    ep_msg_send (msg);
    ep_msg_free (msg);
}

/**
 * e_passwords_ask_password:
 * @title: title for the password dialog
 * @key: key to store the password under
 * @prompt: prompt string
 * @remember_type: whether or not to offer to remember the password,
 * and for how long.
 * @remember: on input, the default state of the remember checkbox.
 * on output, the state of the checkbox when the dialog was closed.
 * @parent: parent window of the dialog, or %NULL
 *
 * Asks the user for a password.
 *
 * Returns: the password, which the caller must free, or %NULL if
 * the user cancelled the operation. *@remember will be set if the
 * return value is non-%NULL and @remember_type is not
 * E_PASSWORDS_DO_NOT_REMEMBER.
 **/
gchar *
e_passwords_ask_password (const gchar *title,
                          const gchar *key,
                          const gchar *prompt,
                          EPasswordsRememberType remember_type,
                          gboolean *remember,
                          GtkWindow *parent)
{
    gchar *passwd;
    EPassMsg *msg;

    g_return_val_if_fail (key != NULL, NULL);

    if ((remember_type & E_PASSWORDS_ONLINE) && !ep_online_state)
        return NULL;

    msg = ep_msg_new (ep_ask_password);
    msg->title = title;
    msg->key = key;
    msg->prompt = prompt;
    msg->flags = remember_type;
    msg->remember = remember;
    msg->parent = parent;

    ep_msg_send (msg);
    passwd = msg->password;
    msg->password = NULL;
    ep_msg_free (msg);

    return passwd;
}