Add support for auto-unloading av the master password

7 files changed, 67 insertions, 5 deletions

diff --git a/libsylph/masterpassword.c b/libsylph/masterpassword.c
index 950b79a..8174def 100644
--- a/libsylph/masterpassword.c
+++ b/libsylph/masterpassword.c
@@ -26,6 +26,7 @@
 #include "prefs_common.h"
 #include "ssl.h"
 #include "utils.h"
+#include "masterpassword.h"
 
 
 gchar *master_password;
@@ -84,9 +85,18 @@ gchar *decrypt_with_master_password(const gchar *str) {
         gchar *new_str;
         gint str_prefix;
 
-        if ((!str) || (!master_password_active()))
+        if ((!str) || (!prefs_common.use_master_password))
                 return g_strdup(str);
 
+        if (master_password == NULL) {
+                /* we have empty or auto unloaded master password */
+                if ((!prefs_common.auto_unload_master_password) ||
+                        (check_master_password_interactively(3) != RC_OK)) {
+                        return g_strdup(str);
+                }
+                debug_print("Reloaded master password\n");
+        }
+
         str_prefix = mpes_string_prefix(str);
         if (!str_prefix)
                 return g_strdup(str);
@@ -113,9 +123,18 @@ gchar *encrypt_with_master_password(const gchar *str) {
         gchar *new_str, *mpes1_str;
         gint length_encrypted;
 
-        if ((!str) || (!master_password_active()))
+        if ((!str) || (!prefs_common.use_master_password))
                 return g_strdup(str);
 
+        if (master_password == NULL) {
+                /* we have empty or auto unloaded master password */
+                if ((!prefs_common.auto_unload_master_password) ||
+                        (check_master_password_interactively(3) != RC_OK)) {
+                        return g_strdup(str);
+                }
+                debug_print("Reloaded master password\n");
+        }
+
         if (encrypt_data(&new_str,
                                          &length_encrypted,
                                          str,
diff --git a/libsylph/prefs_account.c b/libsylph/prefs_account.c
index fc4d8f1..54cbc89 100644
--- a/libsylph/prefs_account.c
+++ b/libsylph/prefs_account.c
@@ -239,6 +239,7 @@ void prefs_account_read_config(PrefsAccount *ac_prefs, const gchar *label)
                                 label);
                         tmp_str = ac_prefs->passwd;
                         ac_prefs->passwd = encrypt_with_master_password(ac_prefs->passwd);
+                        cleanse_buffer(tmp_str, strlen(tmp_str));
                         g_free(tmp_str);
                 }
 
@@ -251,6 +252,7 @@ void prefs_account_read_config(PrefsAccount *ac_prefs, const gchar *label)
                         tmp_str = ac_prefs->smtp_passwd;
                         ac_prefs->smtp_passwd = encrypt_with_master_password(
                                 ac_prefs->smtp_passwd);
+                        cleanse_buffer(tmp_str, strlen(tmp_str));
                         g_free(tmp_str);
                 }
 
diff --git a/libsylph/prefs_common.c b/libsylph/prefs_common.c
index dda4a0f..192964e 100644
--- a/libsylph/prefs_common.c
+++ b/libsylph/prefs_common.c
@@ -425,6 +425,9 @@ static PrefParam param[] = {
          P_STRING},
         {"encrypted_password_min_length", "32",
          &prefs_common.encrypted_password_min_length, P_INT},
+        {"auto_unload_master_password", "FALSE",
+         &prefs_common.auto_unload_master_password,
+         P_BOOL},
 
         /* Interface */
         {"separate_folder", "FALSE", &prefs_common.sep_folder, P_BOOL},
diff --git a/libsylph/prefs_common.h b/libsylph/prefs_common.h
index 92333aa..6f9c364 100644
--- a/libsylph/prefs_common.h
+++ b/libsylph/prefs_common.h
@@ -252,7 +252,8 @@ struct _PrefsCommon
         /* Master password */
         gboolean use_master_password;
         gchar *master_password_hash;
-    guint encrypted_password_min_length;
+        guint encrypted_password_min_length;
+        gboolean auto_unload_master_password;
 
         /* Interface */
         gboolean sep_folder;
diff --git a/src/main.c b/src/main.c
index c6bd812..3c87c70 100644
--- a/src/main.c
+++ b/src/main.c
@@ -412,6 +412,13 @@ int main(int argc, char *argv[])
 
         remote_command_exec();
 
+#if USE_SSL
+        if (prefs_common.auto_unload_master_password && master_password_active()) {
+                debug_print("Auto unloading master password\n");
+                unload_master_password();
+        }
+#endif
+
 #if USE_UPDATE_CHECK
         if (prefs_common.auto_update_check)
                 update_check(FALSE);
diff --git a/src/prefs_common_dialog.c b/src/prefs_common_dialog.c
index 41fdb24..119a056 100644
--- a/src/prefs_common_dialog.c
+++ b/src/prefs_common_dialog.c
@@ -219,6 +219,7 @@ static struct Privacy {
 #if USE_SSL
 static struct MasterPassword {
         GtkWidget *checkbtn_use_master_password;
+        GtkWidget *checkbtn_auto_unload_master_password;
         GtkWidget *spinbtn_encrypted_password_min_length;
 } master_password;
 #endif
@@ -573,6 +574,9 @@ static PrefsUIData ui_data[] = {
 #if USE_SSL
         {"use_master_password", &master_password.checkbtn_use_master_password,
          prefs_set_data_from_toggle, prefs_set_toggle},
+        {"auto_unload_master_password",
+         &master_password.checkbtn_auto_unload_master_password,
+         prefs_set_data_from_toggle, prefs_set_toggle},
         {"encrypted_password_min_length",
          &master_password.spinbtn_encrypted_password_min_length,
          prefs_set_data_from_spinbtn,
@@ -2681,6 +2685,7 @@ static void prefs_master_password_create(void)
         GtkWidget *hbox_spc;
         GtkWidget *label;
         GtkWidget *checkbtn_use_master_password;
+        GtkWidget *checkbtn_auto_unload_master_password;
         GtkWidget *spinbtn_encrypted_password_min_length;
         GtkObject *spinbtn_encrypted_password_min_length_adj;
 
@@ -2706,6 +2711,11 @@ static void prefs_master_password_create(void)
                                                 FALSE,
                                                 0);
 
+        PACK_CHECK_BUTTON (vbox_master_password_suboptions,
+                                           checkbtn_auto_unload_master_password,
+                                           _("Automatically unload master password "
+                                                 "after session initialization"));
+
         hbox1 = gtk_hbox_new (FALSE, 8);
         gtk_widget_show (hbox1);
         gtk_box_pack_start (GTK_BOX (vbox_master_password_suboptions),
@@ -2740,10 +2750,13 @@ static void prefs_master_password_create(void)
                                                                  64,
                                                                  -1);
 
-        SET_TOGGLE_SENSITIVITY (checkbtn_use_master_password, hbox1);
+        SET_TOGGLE_SENSITIVITY (checkbtn_use_master_password,
+                                                        vbox_master_password_suboptions);
 
         master_password.checkbtn_use_master_password
                 = checkbtn_use_master_password;
+        master_password.checkbtn_auto_unload_master_password
+                = checkbtn_auto_unload_master_password;
         master_password.spinbtn_encrypted_password_min_length
                 = spinbtn_encrypted_password_min_length;
 }
diff --git a/src/prefs_ui.c b/src/prefs_ui.c
index 5539f4a..051a058 100644
--- a/src/prefs_ui.c
+++ b/src/prefs_ui.c
@@ -31,6 +31,7 @@
 #include <errno.h>
 
 #include "prefs.h"
+#include "prefs_common.h"
 #include "prefs_ui.h"
 #include "menu.h"
 #include "codeconv.h"
@@ -276,9 +277,25 @@ void prefs_set_data_from_epass_entry(PrefParam *pparam)
         gchar **str;
         const gchar *entry_str;
 
-        if (!master_password_active()) {
+        /* This is where decrypted passwords are encrypted and stored again */
+
+        /* TODO: A potential exploit is disabling master password and then forcing
+         * Sylpheed to store the password
+         */
+
+        /* master_password == NULL for any of the following reasons:
+         * - use_master_password is not enabled (we just save without encrypting)
+         * - master_password is auto unloaded (let the encrypt function handle it)
+         * - undefined reason (refure to store the password)
+         */
+        if (!prefs_common.use_master_password) {
                 prefs_set_data_from_entry(pparam);
                 return;
+        } else if ((master_password == NULL) &&
+                           (!prefs_common.auto_unload_master_password)) {
+                debug_print("Master password enabled, but not loaded for no "
+                                        "apparent reason. Not storing\n");
+                return;
         }
 
         ui_data = (PrefsUIData *)pparam->ui_data;