Added experimental support for using a "trusted device."

This might be a terrible idea, just experimenting here.
icculus · Nov 9, 2015 · 3b807fa · 3b807fa
1 parent de06503
commit 3b807fa
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Showing 5 changed files with 339 additions and 6 deletions.
diff --git a/1pass.c b/1pass.c
@@ -8,14 +8,15 @@
 #include <unistd.h>
 #include <dirent.h>
 #include <signal.h>
-
+#include <mntent.h>
 #include "lua.h"
 #include "lauxlib.h"
 #include "lualib.h"
 #include "pkcs5_pbkdf2.h"
 #include "aes.h"
 #include "base64.h"
 #include "md5.h"
+#include "sha256.h"
 #include "keyhook.h"
 
 #include <gtk/gtk.h>
@@ -363,6 +364,24 @@ static int decryptBase64UsingKey(lua_State *L)
 } // decryptBase64UsingKey
 
 
+static void calcSha256(const BYTE *buf, const size_t len, BYTE *hash)
+{
+    SHA256_CTX sha256;
+    sha256_init(&sha256);
+    sha256_update(&sha256, buf, len);
+    sha256_final(&sha256, hash);
+} // calcSha256
+
+static int calcSha256_Lua(lua_State *L)
+{
+    size_t len = 0;
+    const char *str = luaL_checklstring(L, 1, &len);
+    BYTE hash[32];
+    calcSha256(str, len, hash);
+    return retvalStringBytes(L, hash, sizeof (hash));
+} // calcSha256_Lua
+
+
 static int runGuiPasswordPrompt(lua_State *L)
 {
     const char *hintstr = lua_tostring(L, 1);
@@ -539,7 +558,18 @@ static int guiAddMenuItem(lua_State *L)
 {
     GtkWidget *vbox = (GtkWidget *) lua_touserdata(L, 1);
     const char *label = luaL_checkstring(L, 2);
-    const int callback = makeLuaCallback(L, 3);
+    const int checked = lua_toboolean(L, 3);
+    const int callback = makeLuaCallback(L, 4);
+
+    if (checked)
+    {
+        // !!! FIXME: this is pretty lousy.
+        const size_t len = strlen(label) + 5;
+        char *buf = (char *) alloca(len);
+        snprintf(buf, len, "[X] %s", label);
+        label = buf;
+    } // if
+
     GtkWidget *item = GTK_WIDGET(gtk_button_new_with_label(label));
     g_signal_connect(item, "key-press-event", G_CALLBACK(checkForEscapeKey), NULL);
     g_signal_connect(item, "clicked", G_CALLBACK(clickedMenuItem), (gpointer) ((size_t)callback));
@@ -662,6 +692,29 @@ static int giveControlToGui(lua_State *L)
 } // giveControlToGui
 
 
+static int getMountedDisks(lua_State *L)
+{
+    lua_newtable(L);
+    int luai = 1;
+
+    FILE *mounts = setmntent("/etc/mtab", "r");
+    if (mounts != NULL)
+    {
+        struct mntent *ent = NULL;
+        while ((ent = getmntent(mounts)) != NULL)
+        {
+            lua_pushinteger(luaState, luai);
+            lua_pushstring(luaState, ent->mnt_dir);
+            lua_settable(luaState, -3);
+            luai++;
+        } // while
+        endmntent(mounts);
+    } // if
+
+    return 1;  // return the table.
+} // getMountedDisks
+
+
 static void *luaAlloc(void *ud, void *ptr, size_t osize, size_t nsize)
 {
     if (nsize == 0)
@@ -717,6 +770,8 @@ static int initLua(const int argc, char **argv)
     luaSetCFunc(luaState, runGuiPasswordPrompt, "runGuiPasswordPrompt");
     luaSetCFunc(luaState, copyToClipboard, "copyToClipboard");
     luaSetCFunc(luaState, setPowermateLED_Lua, "setPowermateLED");
+    luaSetCFunc(luaState, calcSha256_Lua, "calcSha256");
+    luaSetCFunc(luaState, getMountedDisks, "getMountedDisks");
 
     luaSetCFunc(luaState, guiCreateTopLevelMenu, "guiCreateTopLevelMenu");
     luaSetCFunc(luaState, guiCreateSubMenu, "guiCreateSubMenu");

diff --git a/1pass.lua b/1pass.lua
@@ -52,7 +52,7 @@ local function load_json(fname)
         return nil
     end
 
-    local str = f:read("*all")
+    local str = f:read("*a")
     f:close()
 
     return load_json_str(str, fname)
@@ -102,7 +102,7 @@ local function getHint()
         return
     end
 
-    local str = "(hint is '" .. f:read("*all") .. "')."
+    local str = "(hint is '" .. f:read("*a") .. "')."
     f:close()
     --print(str)
     return str
@@ -131,6 +131,9 @@ local function setMenuItemSubmenu(menuitem, submenu)
     menuitem["submenu"] = submenu
 end
 
+local function setMenuItemChecked(menuitem, ischecked)
+    menuitem["checked"] = ischecked
+end
 
 
 local function build_secret_menuitem(menu, type, str, hidden)
@@ -423,7 +426,7 @@ local function buildGuiMenuItem(guimenu, item)
             return spawnSubMenu(button, submenu, depth)
         end
     end
-    guiAddMenuItem(guimenu, item["text"], cb)
+    guiAddMenuItem(guimenu, item["text"], item["checked"], cb)
 end
 
 buildGuiMenuList = function(guimenu, list)
@@ -494,6 +497,71 @@ local function launchGuiMenu(topmenu)
     guiShowWindow(guimenu)
 end
 
+local trustedDisks = {}
+
+local function getTrustedDiskChecksumPath(mntpoint)
+    return mntpoint .. "/1pass.dat"
+end
+
+local function getTrustedDiskChecksum(mntpoint)
+    local f = io.open(getTrustedDiskChecksumPath(mntpoint), "rb")
+    if f == nil then
+        return nil
+    end
+
+    local str = f:read("*a")
+    f:close()
+    return calcSha256(str)
+end
+
+local function choseTrustedDisk(mntpoint)
+    if trustedDisks[mntpoint] ~= nil then
+        trustedDisks[mntpoint] = nil  -- no longer check existing trusted disk.
+    else
+        -- !!! FIXME: probably needs a message box if this fails.
+        local checksum = getTrustedDiskChecksum(mntpoint)
+        -- No checksum file yet? Generate and write out a random string.
+        if checksum == nil then
+            local f = io.open("/dev/urandom", "rb")
+            if f ~= nil then
+                local str = f:read(4096)
+                f:close()
+                if (str ~= nil) and (#str == 4096) then
+                    f = io.open(getTrustedDiskChecksumPath(mntpoint), "wb")
+                    if f ~= nil then
+                        if f:write(str) and f:flush() then
+                            checksum = calcSha256(str)
+                        end
+                        f:close()
+                    end
+                end
+            end
+        end
+        trustedDisks[mntpoint] = checksum
+    end
+
+    -- kill the popup if it exists.
+    -- !!! FIXME: put this in its own function, this is a copy/paste from elsewhere.
+    if (keyhookGuiMenus ~= nil) and (keyhookGuiMenus[1] ~= nil) then
+        guiDestroyMenu(keyhookGuiMenus[1])
+    end
+end
+
+local function buildTrustedDeviceMenu()
+    local menu = makeMenu()
+    local disks = getMountedDisks()  -- this is a C function.
+
+    table.sort(disks, function(a, b) return a < b end)
+    for i,v in ipairs(disks) do
+        local item = appendMenuItem(menu, v, function() choseTrustedDisk(v) end)
+        if trustedDisks[v] ~= nil then
+            setMenuItemChecked(item, true)
+        end
+    end
+
+    return menu
+end
+
 function keyhookPressed()  -- not local! Called from C!
     --print("keyhookPressed: running==" .. tostring(keyhookRunning))
     if keyhookRunning then
@@ -502,6 +570,20 @@ function keyhookPressed()  -- not local! Called from C!
 
     keyhookRunning = true
 
+    local allowaccess = true;
+    for mntpoint,checksum in pairs(trustedDisks) do
+        if getTrustedDiskChecksum(mntpoint) ~= checksum then
+            allowaccess = false
+            break
+        end
+    end
+
+    if not allowaccess then
+        -- !!! FIXME: probably needs a message box if this happens.
+        keyhookRunning = false
+        return
+    end
+
     while password == nil do
         password = runGuiPasswordPrompt(getHint())
         if password == nil then
@@ -528,11 +610,14 @@ function keyhookPressed()  -- not local! Called from C!
 
     local topmenu = makeMenu()
     local favesmenu = makeMenu()
+    local securitymenu = makeMenu()
     faveitems = {}
 
     setMenuItemSubmenu(appendMenuItem(topmenu, "Favorites"), favesmenu)
+    setMenuItemSubmenu(appendMenuItem(topmenu, "Security"), securitymenu)
 
-    appendMenuItem(topmenu, "Lock keychain", function() lockKeychain() end)
+    appendMenuItem(securitymenu, "Lock keychain now", function() lockKeychain() end)
+    setMenuItemSubmenu(appendMenuItem(securitymenu, "Require trusted device"), buildTrustedDeviceMenu())
 
     for orderi,type in ipairs(passwordTypeOrdering) do
         local bucket = items[type]

diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -80,6 +80,7 @@ add_executable(1pass
     aes.c
     md5.c
     sha1.c
+    sha256.c
     base64.c
     lua/lapi.c
     lua/ldebug.c