diff --git a/Android.mk b/Android.mk
index ecf2640..deec80a 100644
--- a/Android.mk
+++ b/Android.mk
@@ -1,11 +1,11 @@
+ifneq ($(TARGET_SIMULATOR),true)
+ifeq ($(TARGET_ARCH),arm)
+
 LOCAL_PATH := $(call my-dir)
 include $(CLEAR_VARS)
 
 commands_recovery_local_path := $(LOCAL_PATH)
 
-ifneq ($(TARGET_SIMULATOR),true)
-ifeq ($(TARGET_ARCH),arm)
-
 LOCAL_SRC_FILES := \
 	recovery.c \
 	bootloader.c \
@@ -31,7 +31,13 @@
 
 LOCAL_MODULE_TAGS := eng
 
-LOCAL_STATIC_LIBRARIES := libminzip libunz libmtdutils libmincrypt
+LOCAL_STATIC_LIBRARIES :=
+ifeq ($(TARGET_RECOVERY_UI_LIB),)
+  LOCAL_SRC_FILES += default_recovery_ui.c
+else
+  LOCAL_STATIC_LIBRARIES += $(TARGET_RECOVERY_UI_LIB)
+endif
+LOCAL_STATIC_LIBRARIES += libminzip libunz libmtdutils libmincrypt
 LOCAL_STATIC_LIBRARIES += libminui libpixelflinger_static libpng libcutils
 LOCAL_STATIC_LIBRARIES += libstdc++ libc
 
diff --git a/default_recovery_ui.c b/default_recovery_ui.c
new file mode 100644
index 0000000..d4e6204
--- /dev/null
+++ b/default_recovery_ui.c
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <linux/input.h>
+
+#include "recovery_ui.h"
+#include "common.h"
+
+char* MENU_HEADERS[] = { "Android system recovery utility",
+                         "",
+                         NULL };
+
+char* MENU_ITEMS[] = { "reboot system now",
+                       "apply sdcard:update.zip",
+                       "wipe data/factory reset",
+                       "wipe cache partition",
+                       NULL };
+
+int device_toggle_display(volatile char* key_pressed, int key_code) {
+    return key_code == KEY_HOME;
+}
+
+int device_reboot_now(volatile char* key_pressed, int key_code) {
+    return 0;
+}
+
+int device_handle_key(int key_code, int visible) {
+    if (visible) {
+        switch (key_code) {
+            case KEY_DOWN:
+            case KEY_VOLUMEDOWN:
+                return HIGHLIGHT_DOWN;
+
+            case KEY_UP:
+            case KEY_VOLUMEUP:
+                return HIGHLIGHT_UP;
+
+            case KEY_ENTER:
+                return SELECT_ITEM;
+        }
+    }
+
+    return NO_ACTION;
+}
+
+int device_perform_action(int which) {
+    return which;
+}
+
+int device_wipe_data() {
+    return 0;
+}
diff --git a/install.c b/install.c
index 2c557ea..7710cec 100644
--- a/install.c
+++ b/install.c
@@ -234,20 +234,8 @@
 }
 
 static int
-handle_update_package(const char *path, ZipArchive *zip,
-                      const RSAPublicKey *keys, int numKeys)
+handle_update_package(const char *path, ZipArchive *zip)
 {
-    // Give verification half the progress bar...
-    ui_print("Verifying update package...\n");
-    ui_show_progress(
-            VERIFICATION_PROGRESS_FRACTION,
-            VERIFICATION_PROGRESS_TIME);
-
-    if (!verify_jar_signature(zip, keys, numKeys)) {
-        LOGE("Verification failed\n");
-        return INSTALL_CORRUPT;
-    }
-
     // Update should take the rest of the progress bar.
     ui_print("Installing update...\n");
 
@@ -360,10 +348,25 @@
     }
     LOGI("%d key(s) loaded from %s\n", numKeys, PUBLIC_KEYS_FILE);
 
+    // Give verification half the progress bar...
+    ui_print("Verifying update package...\n");
+    ui_show_progress(
+            VERIFICATION_PROGRESS_FRACTION,
+            VERIFICATION_PROGRESS_TIME);
+
+    int err;
+    err = verify_file(path, loadedKeys, numKeys);
+    free(loadedKeys);
+    LOGI("verify_file returned %d\n", err);
+    if (err != VERIFY_SUCCESS) {
+        LOGE("signature verification failed\n");
+        return INSTALL_CORRUPT;
+    }
+
     /* Try to open the package.
      */
     ZipArchive zip;
-    int err = mzOpenZipArchive(path, &zip);
+    err = mzOpenZipArchive(path, &zip);
     if (err != 0) {
         LOGE("Can't open %s\n(%s)\n", path, err != -1 ? strerror(err) : "bad");
         return INSTALL_CORRUPT;
@@ -371,8 +374,7 @@
 
     /* Verify and install the contents of the package.
      */
-    int status = handle_update_package(path, &zip, loadedKeys, numKeys);
+    int status = handle_update_package(path, &zip);
     mzCloseZipArchive(&zip);
-    free(loadedKeys);
     return status;
 }
diff --git a/minui/graphics.c b/minui/graphics.c
index 06c5fdf..adbfc09 100644
--- a/minui/graphics.c
+++ b/minui/graphics.c
@@ -115,6 +115,7 @@
     if (n > 1) return;
     vi.yres_virtual = vi.yres * 2;
     vi.yoffset = n * vi.yres;
+    vi.bits_per_pixel = 16;
     if (ioctl(gr_fb_fd, FBIOPUT_VSCREENINFO, &vi) < 0) {
         perror("active fb swap failed");
     }
diff --git a/minui/minui.h b/minui/minui.h
index 80b47a4..567d421 100644
--- a/minui/minui.h
+++ b/minui/minui.h
@@ -41,22 +41,6 @@
 // see http://www.mjmwired.net/kernel/Documentation/input/ for info.
 struct input_event;
 
-// Dream-specific key codes
-#define KEY_DREAM_HOME        102  // = KEY_HOME
-#define KEY_DREAM_RED         107  // = KEY_END
-#define KEY_DREAM_VOLUMEDOWN  114  // = KEY_VOLUMEDOWN
-#define KEY_DREAM_VOLUMEUP    115  // = KEY_VOLUMEUP
-#define KEY_DREAM_SYM         127  // = KEY_COMPOSE
-#define KEY_DREAM_MENU        139  // = KEY_MENU
-#define KEY_DREAM_BACK        158  // = KEY_BACK
-#define KEY_DREAM_FOCUS       211  // = KEY_HP (light touch on camera)
-#define KEY_DREAM_CAMERA      212  // = KEY_CAMERA
-#define KEY_DREAM_AT          215  // = KEY_EMAIL
-#define KEY_DREAM_GREEN       231
-#define KEY_DREAM_FATTOUCH    258  // = BTN_2 ???
-#define KEY_DREAM_BALL        272  // = BTN_MOUSE
-#define KEY_DREAM_TOUCH       330  // = BTN_TOUCH
-
 int ev_init(void);
 void ev_exit(void);
 int ev_get(struct input_event *ev, unsigned dont_wait);
diff --git a/recovery.c b/recovery.c
index 0ff5d94..33cbc13 100644
--- a/recovery.c
+++ b/recovery.c
@@ -36,6 +36,7 @@
 #include "minui/minui.h"
 #include "minzip/DirUtil.h"
 #include "roots.h"
+#include "recovery_ui.h"
 
 static const struct option OPTIONS[] = {
   { "send_intent", required_argument, NULL, 's' },
@@ -206,6 +207,15 @@
     set_bootloader_message(&boot);
 }
 
+static void
+set_sdcard_update_bootloader_message()
+{
+    struct bootloader_message boot;
+    memset(&boot, 0, sizeof(boot));
+    strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
+    strlcpy(boot.recovery, "recovery\n", sizeof(boot.recovery));
+    set_bootloader_message(&boot);
+}
 
 // clear the recovery command and prepare to boot a (hopefully working) system,
 // copy our log file to cache as well (for the system to read), and
@@ -272,26 +282,25 @@
 static void
 prompt_and_wait()
 {
-    char* headers[] = { "Android system recovery <"
+    char* title[] = { "Android system recovery <"
                           EXPAND(RECOVERY_API_VERSION) "e>",
-                        "",
-                        "Use trackball to highlight;",
-                        "click to select.",
-                        "",
-                        NULL };
-
-    // these constants correspond to elements of the items[] list.
-#define ITEM_REBOOT        0
-#define ITEM_APPLY_SDCARD  1
-#define ITEM_WIPE_DATA     2
-#define ITEM_WIPE_CACHE    3
-    char* items[] = { "reboot system now [Home+Back]",
-                      "apply sdcard:update.zip [Alt+S]",
-                      "wipe data/factory reset [Alt+W]",
-                      "wipe cache partition",
+                      "",
                       NULL };
 
-    ui_start_menu(headers, items);
+    // count the number of lines in our title, plus the
+    // product-provided headers.
+    int count = 0;
+    char** p;
+    for (p = title; *p; ++p, ++count);
+    for (p = MENU_HEADERS; *p; ++p, ++count);
+
+    char** headers = malloc((count+1) * sizeof(char*));
+    char** h = headers;
+    for (p = title; *p; ++p, ++h) *h = *p;
+    for (p = MENU_HEADERS; *p; ++p, ++h) *h = *p;
+    *h = NULL;
+
+    ui_start_menu(headers, MENU_ITEMS);
     int selected = 0;
     int chosen_item = -1;
 
@@ -299,29 +308,28 @@
     ui_reset_progress();
     for (;;) {
         int key = ui_wait_key();
-        int alt = ui_key_pressed(KEY_LEFTALT) || ui_key_pressed(KEY_RIGHTALT);
         int visible = ui_text_visible();
 
-        if (key == KEY_DREAM_BACK && ui_key_pressed(KEY_DREAM_HOME)) {
-            // Wait for the keys to be released, to avoid triggering
-            // special boot modes (like coming back into recovery!).
-            while (ui_key_pressed(KEY_DREAM_BACK) ||
-                   ui_key_pressed(KEY_DREAM_HOME)) {
-                usleep(1000);
+        int action = device_handle_key(key, visible);
+
+        if (action < 0) {
+            switch (action) {
+                case HIGHLIGHT_UP:
+                    --selected;
+                    selected = ui_menu_select(selected);
+                    break;
+                case HIGHLIGHT_DOWN:
+                    ++selected;
+                    selected = ui_menu_select(selected);
+                    break;
+                case SELECT_ITEM:
+                    chosen_item = selected;
+                    break;
+                case NO_ACTION:
+                    break;
             }
-            chosen_item = ITEM_REBOOT;
-        } else if (alt && key == KEY_W) {
-            chosen_item = ITEM_WIPE_DATA;
-        } else if (alt && key == KEY_S) {
-            chosen_item = ITEM_APPLY_SDCARD;
-        } else if ((key == KEY_DOWN || key == KEY_VOLUMEDOWN) && visible) {
-            ++selected;
-            selected = ui_menu_select(selected);
-        } else if ((key == KEY_UP || key == KEY_VOLUMEUP) && visible) {
-            --selected;
-            selected = ui_menu_select(selected);
-        } else if (key == BTN_MOUSE && visible) {
-            chosen_item = selected;
+        } else {
+            chosen_item = action;
         }
 
         if (chosen_item >= 0) {
@@ -329,12 +337,18 @@
             // on the screen.
             ui_end_menu();
 
+            // device-specific code may take some action here.  It may
+            // return one of the core actions handled in the switch
+            // statement below.
+            chosen_item = device_perform_action(chosen_item);
+
             switch (chosen_item) {
                 case ITEM_REBOOT:
                     return;
 
                 case ITEM_WIPE_DATA:
                     ui_print("\n-- Wiping data...\n");
+                    device_wipe_data();
                     erase_root("DATA:");
                     erase_root("CACHE:");
                     ui_print("Data wipe complete.\n");
@@ -350,6 +364,7 @@
 
                 case ITEM_APPLY_SDCARD:
                     ui_print("\n-- Install from sdcard...\n");
+                    set_sdcard_update_bootloader_message();
                     int status = install_package(SDCARD_PACKAGE_FILE);
                     if (status != INSTALL_SUCCESS) {
                         ui_set_background(BACKGROUND_ICON_ERROR);
@@ -358,8 +373,8 @@
                         return;  // reboot if logs aren't visible
                     } else {
                       if (firmware_update_pending()) {
-                        ui_print("\nReboot via home+back or menu\n"
-                                 "to complete installation.\n");
+                        ui_print("\nReboot via menu to complete\n"
+                                 "installation.\n");
                       } else {
                         ui_print("\nInstall from sdcard complete.\n");
                       }
@@ -369,7 +384,7 @@
 
             // if we didn't return from this function to reboot, show
             // the menu again.
-            ui_start_menu(headers, items);
+            ui_start_menu(headers, MENU_ITEMS);
             selected = 0;
             chosen_item = -1;
 
@@ -435,10 +450,14 @@
     if (update_package != NULL) {
         status = install_package(update_package);
         if (status != INSTALL_SUCCESS) ui_print("Installation aborted.\n");
-    } else if (wipe_data || wipe_cache) {
-        if (wipe_data && erase_root("DATA:")) status = INSTALL_ERROR;
+    } else if (wipe_data) {
+        if (device_wipe_data()) status = INSTALL_ERROR;
+        if (erase_root("DATA:")) status = INSTALL_ERROR;
         if (wipe_cache && erase_root("CACHE:")) status = INSTALL_ERROR;
         if (status != INSTALL_SUCCESS) ui_print("Data wipe failed.\n");
+    } else if (wipe_cache) {
+        if (wipe_cache && erase_root("CACHE:")) status = INSTALL_ERROR;
+        if (status != INSTALL_SUCCESS) ui_print("Cache wipe failed.\n");
     } else {
         status = INSTALL_ERROR;  // No command specified
     }
diff --git a/recovery_ui.h b/recovery_ui.h
new file mode 100644
index 0000000..8818ef3
--- /dev/null
+++ b/recovery_ui.h
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _RECOVERY_UI_H
+#define _RECOVERY_UI_H
+
+// Called in the input thread when a new key (key_code) is pressed.
+// *key_pressed is an array of KEY_MAX+1 bytes indicating which other
+// keys are already pressed.  Return true if the text display should
+// be toggled.
+extern int device_toggle_display(volatile char* key_pressed, int key_code);
+
+// Called in the input thread when a new key (key_code) is pressed.
+// *key_pressed is an array of KEY_MAX+1 bytes indicating which other
+// keys are already pressed.  Return true if the device should reboot
+// immediately.
+extern int device_reboot_now(volatile char* key_pressed, int key_code);
+
+// Called from the main thread when recovery is waiting for input and
+// a key is pressed.  key is the code of the key pressed; visible is
+// true if the recovery menu is being shown.  Implementations can call
+// ui_key_pressed() to discover if other keys are being held down.
+// Return one of the defined constants below in order to:
+//
+//   - move the menu highlight (HIGHLIGHT_*)
+//   - invoke the highlighted item (SELECT_ITEM)
+//   - do nothing (NO_ACTION)
+//   - invoke a specific action (a menu position: any non-negative number)
+extern int device_handle_key(int key, int visible);
+
+// Perform a recovery action selected from the menu.  'which' will be
+// the item number of the selected menu item, or a non-negative number
+// returned from device_handle_key().  The menu will be hidden when
+// this is called; implementations can call ui_print() to print
+// information to the screen.
+extern int device_perform_action(int which);
+
+// Called when we do a wipe data/factory reset operation (either via a
+// reboot from the main system with the --wipe_data flag, or when the
+// user boots into recovery manually and selects the option from the
+// menu.)  Can perform whatever device-specific wiping actions are
+// needed.  Return 0 on success.  The userdata and cache partitions
+// are erased after this returns (whether it returns success or not).
+int device_wipe_data();
+
+#define NO_ACTION           -1
+
+#define HIGHLIGHT_UP        -2
+#define HIGHLIGHT_DOWN      -3
+#define SELECT_ITEM         -4
+
+#define ITEM_REBOOT          0
+#define ITEM_APPLY_SDCARD    1
+#define ITEM_WIPE_DATA       2
+#define ITEM_WIPE_CACHE      3
+
+// Header text to display above the main menu.
+extern char* MENU_HEADERS[];
+
+// Text of menu items.
+extern char* MENU_ITEMS[];
+
+#endif
diff --git a/res/images/icon_error.png b/res/images/icon_error.png
index 7064c2e..6cb71c0 100644
--- a/res/images/icon_error.png
+++ b/res/images/icon_error.png
Binary files differ
diff --git a/res/images/icon_firmware_install.png b/res/images/icon_firmware_install.png
index ee2afac..8bfe775 100644
--- a/res/images/icon_firmware_install.png
+++ b/res/images/icon_firmware_install.png
Binary files differ
diff --git a/res/images/icon_installing.png b/res/images/icon_installing.png
index f24f2e3..1aeb9d9 100644
--- a/res/images/icon_installing.png
+++ b/res/images/icon_installing.png
Binary files differ
diff --git a/roots.c b/roots.c
index 6a6cf8a..8f8dace 100644
--- a/roots.c
+++ b/roots.c
@@ -52,6 +52,7 @@
     { "RECOVERY:", g_mtd_device, NULL, "recovery", "/", g_raw },
     { "SDCARD:", "/dev/block/mmcblk0p1", "/dev/block/mmcblk0", NULL, "/sdcard", "vfat" },
     { "SYSTEM:", g_mtd_device, NULL, "system", "/system", "yaffs2" },
+    { "MBM:", g_mtd_device, NULL, "mbm", NULL, g_raw },
     { "TMP:", NULL, NULL, NULL, "/tmp", NULL },
 };
 #define NUM_ROOTS (sizeof(g_roots) / sizeof(g_roots[0]))
diff --git a/ui.c b/ui.c
index b84f172..0a8b985 100644
--- a/ui.c
+++ b/ui.c
@@ -27,6 +27,7 @@
 
 #include "common.h"
 #include "minui/minui.h"
+#include "recovery_ui.h"
 
 #define MAX_COLS 64
 #define MAX_ROWS 32
@@ -307,20 +308,14 @@
         }
         pthread_mutex_unlock(&key_queue_mutex);
 
-        // Alt+L or Home+End: toggle log display
-        int alt = key_pressed[KEY_LEFTALT] || key_pressed[KEY_RIGHTALT];
-        if ((alt && ev.code == KEY_L && ev.value > 0) ||
-            (key_pressed[KEY_HOME] && ev.code == KEY_END && ev.value > 0)) {
+        if (ev.value > 0 && device_toggle_display(key_pressed, ev.code)) {
             pthread_mutex_lock(&gUpdateMutex);
             show_text = !show_text;
             update_screen_locked();
             pthread_mutex_unlock(&gUpdateMutex);
         }
 
-        // Green+Menu+Red: reboot immediately
-        if (ev.code == KEY_DREAM_RED &&
-            key_pressed[KEY_DREAM_MENU] &&
-            key_pressed[KEY_DREAM_GREEN]) {
+        if (ev.value > 0 && device_reboot_now(key_pressed, ev.code)) {
             reboot(RB_AUTOBOOT);
         }
     }
diff --git a/updater/Android.mk b/updater/Android.mk
index 897b9d7..d4a4e33 100644
--- a/updater/Android.mk
+++ b/updater/Android.mk
@@ -18,11 +18,47 @@
 
 LOCAL_SRC_FILES := $(updater_src_files)
 
-LOCAL_STATIC_LIBRARIES := libapplypatch libedify libmtdutils libminzip libz
+LOCAL_STATIC_LIBRARIES := $(TARGET_RECOVERY_UPDATER_LIBS) $(TARGET_RECOVERY_UPDATER_EXTRA_LIBS)
+LOCAL_STATIC_LIBRARIES += libapplypatch libedify libmtdutils libminzip libz
 LOCAL_STATIC_LIBRARIES += libmincrypt libbz
 LOCAL_STATIC_LIBRARIES += libcutils libstdc++ libc
 LOCAL_C_INCLUDES += $(LOCAL_PATH)/..
 
+# Each library in TARGET_RECOVERY_UPDATER_LIBS should have a function
+# named "Register_<libname>()".  Here we emit a little C function that
+# gets #included by updater.c.  It calls all those registration
+# functions.
+
+# Devices can also add libraries to TARGET_RECOVERY_UPDATER_EXTRA_LIBS.
+# These libs are also linked in with updater, but we don't try to call
+# any sort of registration function for these.  Use this variable for
+# any subsidiary static libraries required for your registered
+# extension libs.
+
+inc := $(call intermediates-dir-for,PACKAGING,updater_extensions)/register.inc
+
+# During the first pass of reading the makefiles, we dump the list of
+# extension libs to a temp file, then copy that to the ".list" file if
+# it is different than the existing .list (if any).  The register.inc
+# file then uses the .list as a prerequisite, so it is only rebuilt
+# (and updater.o recompiled) when the list of extension libs changes.
+
+junk := $(shell mkdir -p $(dir $(inc));\
+	        echo $(TARGET_RECOVERY_UPDATER_LIBS) > $(inc).temp;\
+	        diff -q $(inc).temp $(inc).list || cp -f $(inc).temp $(inc).list)
+
+$(inc) : libs := $(TARGET_RECOVERY_UPDATER_LIBS)
+$(inc) : $(inc).list
+	$(hide) mkdir -p $(dir $@)
+	$(hide) echo "" > $@
+	$(hide) $(foreach lib,$(libs),echo "extern void Register_$(lib)(void);" >> $@)
+	$(hide) echo "void RegisterDeviceExtensions() {" >> $@
+	$(hide) $(foreach lib,$(libs),echo "  Register_$(lib)();" >> $@)
+	$(hide) echo "}" >> $@
+
+$(call intermediates-dir-for,EXECUTABLES,updater)/updater.o : $(inc)
+LOCAL_C_INCLUDES += $(dir $(inc))
+
 LOCAL_MODULE := updater
 
 LOCAL_FORCE_STATIC_EXECUTABLE := true
diff --git a/updater/updater.c b/updater/updater.c
index 31d93ae..1aa277c 100644
--- a/updater/updater.c
+++ b/updater/updater.c
@@ -23,6 +23,11 @@
 #include "install.h"
 #include "minzip/Zip.h"
 
+// Generated by the makefile, this function defines the
+// RegisterDeviceExtensions() function, which calls all the
+// registration functions for device-specific extensions.
+#include "register.inc"
+
 // Where in the package we expect to find the edify script to execute.
 // (Note it's "updateR-script", not the older "update-script".)
 #define SCRIPT_NAME "META-INF/com/google/android/updater-script"
@@ -76,6 +81,7 @@
 
     RegisterBuiltins();
     RegisterInstallFunctions();
+    RegisterDeviceExtensions();
     FinishRegistration();
 
     // Parse the script.
diff --git a/verifier.c b/verifier.c
index 1180ae8..f2491a1 100644
--- a/verifier.c
+++ b/verifier.c
@@ -17,345 +17,168 @@
 #include "common.h"
 #include "verifier.h"
 
-#include "minzip/Zip.h"
 #include "mincrypt/rsa.h"
 #include "mincrypt/sha.h"
 
-#include <netinet/in.h>  /* required for resolv.h */
-#include <resolv.h>      /* for base64 codec */
 #include <string.h>
+#include <stdio.h>
+#include <errno.h>
 
-/* Return an allocated buffer with the contents of a zip file entry. */
-static char *slurpEntry(const ZipArchive *pArchive, const ZipEntry *pEntry) {
-    if (!mzIsZipEntryIntact(pArchive, pEntry)) {
-        UnterminatedString fn = mzGetZipEntryFileName(pEntry);
-        LOGE("Invalid %.*s\n", fn.len, fn.str);
-        return NULL;
+// Look for an RSA signature embedded in the .ZIP file comment given
+// the path to the zip.  Verify it matches one of the given public
+// keys.
+//
+// Return VERIFY_SUCCESS, VERIFY_FAILURE (if any error is encountered
+// or no key matches the signature).
+
+int verify_file(const char* path, const RSAPublicKey *pKeys, unsigned int numKeys) {
+    ui_set_progress(0.0);
+
+    FILE* f = fopen(path, "rb");
+    if (f == NULL) {
+        LOGE("failed to open %s (%s)\n", path, strerror(errno));
+        return VERIFY_FAILURE;
     }
 
-    int len = mzGetZipEntryUncompLen(pEntry);
-    char *buf = malloc(len + 1);
-    if (buf == NULL) {
-        UnterminatedString fn = mzGetZipEntryFileName(pEntry);
-        LOGE("Can't allocate %d bytes for %.*s\n", len, fn.len, fn.str);
-        return NULL;
+    // An archive with a whole-file signature will end in six bytes:
+    //
+    //   $ff $ff (2-byte comment size) (2-byte signature start)
+    //
+    // (As far as the ZIP format is concerned, these are part of the
+    // archive comment.)  We start by reading this footer, this tells
+    // us how far back from the end we have to start reading to find
+    // the whole comment.
+
+#define FOOTER_SIZE 6
+
+    if (fseek(f, -FOOTER_SIZE, SEEK_END) != 0) {
+        LOGE("failed to seek in %s (%s)\n", path, strerror(errno));
+        fclose(f);
+        return VERIFY_FAILURE;
     }
 
-    if (!mzReadZipEntry(pArchive, pEntry, buf, len)) {
-        UnterminatedString fn = mzGetZipEntryFileName(pEntry);
-        LOGE("Can't read %.*s\n", fn.len, fn.str);
-        free(buf);
-        return NULL;
+    unsigned char footer[FOOTER_SIZE];
+    if (fread(footer, 1, FOOTER_SIZE, f) != FOOTER_SIZE) {
+        LOGE("failed to read footer from %s (%s)\n", path, strerror(errno));
+        fclose(f);
+        return VERIFY_FAILURE;
     }
 
-    buf[len] = '\0';
-    return buf;
-}
-
-
-struct DigestContext {
-    SHA_CTX digest;
-    unsigned *doneBytes;
-    unsigned totalBytes;
-};
-
-
-/* mzProcessZipEntryContents callback to update an SHA-1 hash context. */
-static bool updateHash(const unsigned char *data, int dataLen, void *cookie) {
-    struct DigestContext *context = (struct DigestContext *) cookie;
-    SHA_update(&context->digest, data, dataLen);
-    if (context->doneBytes != NULL) {
-        *context->doneBytes += dataLen;
-        if (context->totalBytes > 0) {
-            ui_set_progress(*context->doneBytes * 1.0 / context->totalBytes);
-        }
-    }
-    return true;
-}
-
-
-/* Get the SHA-1 digest of a zip file entry. */
-static bool digestEntry(const ZipArchive *pArchive, const ZipEntry *pEntry,
-        unsigned *doneBytes, unsigned totalBytes,
-        uint8_t digest[SHA_DIGEST_SIZE]) {
-    struct DigestContext context;
-    SHA_init(&context.digest);
-    context.doneBytes = doneBytes;
-    context.totalBytes = totalBytes;
-    if (!mzProcessZipEntryContents(pArchive, pEntry, updateHash, &context)) {
-        UnterminatedString fn = mzGetZipEntryFileName(pEntry);
-        LOGE("Can't digest %.*s\n", fn.len, fn.str);
-        return false;
+    if (footer[2] != 0xff || footer[3] != 0xff) {
+        fclose(f);
+        return VERIFY_FAILURE;
     }
 
-    memcpy(digest, SHA_final(&context.digest), SHA_DIGEST_SIZE);
+    int comment_size = footer[4] + (footer[5] << 8);
+    int signature_start = footer[0] + (footer[1] << 8);
+    LOGI("comment is %d bytes; signature %d bytes from end\n",
+         comment_size, signature_start);
 
-#ifdef LOG_VERBOSE
-    UnterminatedString fn = mzGetZipEntryFileName(pEntry);
-    char base64[SHA_DIGEST_SIZE * 3];
-    b64_ntop(digest, SHA_DIGEST_SIZE, base64, sizeof(base64));
-    LOGV("sha1(%.*s) = %s\n", fn.len, fn.str, base64);
-#endif
+    if (signature_start - FOOTER_SIZE < RSANUMBYTES) {
+        // "signature" block isn't big enough to contain an RSA block.
+        LOGE("signature is too short\n");
+        fclose(f);
+        return VERIFY_FAILURE;
+    }
 
-    return true;
-}
+#define EOCD_HEADER_SIZE 22
 
+    // The end-of-central-directory record is 22 bytes plus any
+    // comment length.
+    size_t eocd_size = comment_size + EOCD_HEADER_SIZE;
 
-/* Find a /META-INF/xxx.SF signature file signed by a matching xxx.RSA file. */
-static const ZipEntry *verifySignature(const ZipArchive *pArchive,
-        const RSAPublicKey *pKeys, unsigned int numKeys) {
-    static const char prefix[] = "META-INF/";
-    static const char rsa[] = ".RSA", sf[] = ".SF";
+    if (fseek(f, -eocd_size, SEEK_END) != 0) {
+        LOGE("failed to seek in %s (%s)\n", path, strerror(errno));
+        fclose(f);
+        return VERIFY_FAILURE;
+    }
 
-    unsigned int i, j;
-    for (i = 0; i < mzZipEntryCount(pArchive); ++i) {
-        const ZipEntry *rsaEntry = mzGetZipEntryAt(pArchive, i);
-        UnterminatedString rsaName = mzGetZipEntryFileName(rsaEntry);
-        int rsaLen = mzGetZipEntryUncompLen(rsaEntry);
-        if (rsaLen >= RSANUMBYTES && rsaName.len > sizeof(prefix) &&
-                !strncmp(rsaName.str, prefix, sizeof(prefix) - 1) &&
-                !strncmp(rsaName.str + rsaName.len - sizeof(rsa) + 1,
-                         rsa, sizeof(rsa) - 1)) {
-            char *sfName = malloc(rsaName.len - sizeof(rsa) + sizeof(sf) + 1);
-            if (sfName == NULL) {
-                LOGE("Can't allocate %d bytes for filename\n", rsaName.len);
-                continue;
-            }
+    // Determine how much of the file is covered by the signature.
+    // This is everything except the signature data and length, which
+    // includes all of the EOCD except for the comment length field (2
+    // bytes) and the comment data.
+    size_t signed_len = ftell(f) + EOCD_HEADER_SIZE - 2;
 
-            /* Replace .RSA with .SF */
-            strncpy(sfName, rsaName.str, rsaName.len - sizeof(rsa) + 1);
-            strcpy(sfName + rsaName.len - sizeof(rsa) + 1, sf);
-            const ZipEntry *sfEntry = mzFindZipEntry(pArchive, sfName);
+    unsigned char* eocd = malloc(eocd_size);
+    if (eocd == NULL) {
+        LOGE("malloc for EOCD record failed\n");
+        fclose(f);
+        return VERIFY_FAILURE;
+    }
+    if (fread(eocd, 1, eocd_size, f) != eocd_size) {
+        LOGE("failed to read eocd from %s (%s)\n", path, strerror(errno));
+        fclose(f);
+        return VERIFY_FAILURE;
+    }
 
-            if (sfEntry == NULL) {
-                LOGW("Missing signature file %s\n", sfName);
-                free(sfName);
-                continue;
-            }
+    // If this is really is the EOCD record, it will begin with the
+    // magic number $50 $4b $05 $06.
+    if (eocd[0] != 0x50 || eocd[1] != 0x4b ||
+        eocd[2] != 0x05 || eocd[3] != 0x06) {
+        LOGE("signature length doesn't match EOCD marker\n");
+        fclose(f);
+        return VERIFY_FAILURE;
+    }
 
-            free(sfName);
-
-            uint8_t sfDigest[SHA_DIGEST_SIZE];
-            if (!digestEntry(pArchive, sfEntry, NULL, 0, sfDigest)) continue;
-
-            char *rsaBuf = slurpEntry(pArchive, rsaEntry);
-            if (rsaBuf == NULL) continue;
-
-            /* Try to verify the signature with all the keys. */
-            uint8_t *sig = (uint8_t *) rsaBuf + rsaLen - RSANUMBYTES;
-            for (j = 0; j < numKeys; ++j) {
-                if (RSA_verify(&pKeys[j], sig, RSANUMBYTES, sfDigest)) {
-                    free(rsaBuf);
-                    LOGI("Verified %.*s\n", rsaName.len, rsaName.str);
-                    return sfEntry;
-                }
-            }
-
-            free(rsaBuf);
-            LOGW("Can't verify %.*s\n", rsaName.len, rsaName.str);
+    int i;
+    for (i = 4; i < eocd_size-3; ++i) {
+        if (eocd[i  ] == 0x50 && eocd[i+1] == 0x4b &&
+            eocd[i+2] == 0x05 && eocd[i+1] == 0x06) {
+            // if the sequence $50 $4b $05 $06 appears anywhere after
+            // the real one, minzip will find the later (wrong) one,
+            // which could be exploitable.  Fail verification if
+            // this sequence occurs anywhere after the real one.
+            LOGE("EOCD marker occurs after start of EOCD\n");
+            fclose(f);
+            return VERIFY_FAILURE;
         }
     }
 
-    LOGE("No signature (%d files)\n", mzZipEntryCount(pArchive));
-    return NULL;
-}
+#define BUFFER_SIZE 4096
 
+    SHA_CTX ctx;
+    SHA_init(&ctx);
+    unsigned char* buffer = malloc(BUFFER_SIZE);
+    if (buffer == NULL) {
+        LOGE("failed to alloc memory for sha1 buffer\n");
+        fclose(f);
+        return VERIFY_FAILURE;
+    }
 
-/* Verify /META-INF/MANIFEST.MF against the digest in a signature file. */
-static const ZipEntry *verifyManifest(const ZipArchive *pArchive,
-        const ZipEntry *sfEntry) {
-    static const char prefix[] = "SHA1-Digest-Manifest: ", eol[] = "\r\n";
-    uint8_t expected[SHA_DIGEST_SIZE + 3], actual[SHA_DIGEST_SIZE];
-
-    char *sfBuf = slurpEntry(pArchive, sfEntry);
-    if (sfBuf == NULL) return NULL;
-
-    char *line, *save;
-    for (line = strtok_r(sfBuf, eol, &save); line != NULL;
-         line = strtok_r(NULL, eol, &save)) {
-        if (!strncasecmp(prefix, line, sizeof(prefix) - 1)) {
-            UnterminatedString fn = mzGetZipEntryFileName(sfEntry);
-            const char *digest = line + sizeof(prefix) - 1;
-            int n = b64_pton(digest, expected, sizeof(expected));
-            if (n != SHA_DIGEST_SIZE) {
-                LOGE("Invalid base64 in %.*s: %s (%d)\n",
-                        fn.len, fn.str, digest, n);
-                line = NULL;
-            }
-            break;
+    double frac = -1.0;
+    size_t so_far = 0;
+    fseek(f, 0, SEEK_SET);
+    while (so_far < signed_len) {
+        int size = BUFFER_SIZE;
+        if (signed_len - so_far < size) size = signed_len - so_far;
+        if (fread(buffer, 1, size, f) != size) {
+            LOGE("failed to read data from %s (%s)\n", path, strerror(errno));
+            fclose(f);
+            return VERIFY_FAILURE;
+        }
+        SHA_update(&ctx, buffer, size);
+        so_far += size;
+        double f = so_far / (double)signed_len;
+        if (f > frac + 0.02 || size == so_far) {
+            ui_set_progress(f);
+            frac = f;
         }
     }
+    fclose(f);
+    free(buffer);
 
-    free(sfBuf);
-
-    if (line == NULL) {
-        LOGE("No digest manifest in signature file\n");
-        return false;
-    }
-
-    const char *mfName = "META-INF/MANIFEST.MF";
-    const ZipEntry *mfEntry = mzFindZipEntry(pArchive, mfName);
-    if (mfEntry == NULL) {
-        LOGE("No manifest file %s\n", mfName);
-        return NULL;
-    }
-
-    if (!digestEntry(pArchive, mfEntry, NULL, 0, actual)) return NULL;
-    if (memcmp(expected, actual, SHA_DIGEST_SIZE)) {
-        UnterminatedString fn = mzGetZipEntryFileName(sfEntry);
-        LOGE("Wrong digest for %s in %.*s\n", mfName, fn.len, fn.str);
-        return NULL;
-    }
-
-    LOGI("Verified %s\n", mfName);
-    return mfEntry;
-}
-
-
-/* Verify all the files in a Zip archive against the manifest. */
-static bool verifyArchive(const ZipArchive *pArchive, const ZipEntry *mfEntry) {
-    static const char namePrefix[] = "Name: ";
-    static const char contPrefix[] = " ";  // Continuation of the filename
-    static const char digestPrefix[] = "SHA1-Digest: ";
-    static const char eol[] = "\r\n";
-
-    char *mfBuf = slurpEntry(pArchive, mfEntry);
-    if (mfBuf == NULL) return false;
-
-    /* we're using calloc() here, so the initial state of the array is false */
-    bool *unverified = (bool *) calloc(mzZipEntryCount(pArchive), sizeof(bool));
-    if (unverified == NULL) {
-        LOGE("Can't allocate valid flags\n");
-        free(mfBuf);
-        return false;
-    }
-
-    /* Mark all the files in the archive that need to be verified.
-     * As we scan the manifest and check signatures, we'll unset these flags.
-     * At the end, we'll make sure that all the flags are unset.
-     */
-
-    unsigned i, totalBytes = 0;
-    for (i = 0; i < mzZipEntryCount(pArchive); ++i) {
-        const ZipEntry *entry = mzGetZipEntryAt(pArchive, i);
-        UnterminatedString fn = mzGetZipEntryFileName(entry);
-        int len = mzGetZipEntryUncompLen(entry);
-
-        // Don't validate: directories, the manifest, *.RSA, and *.SF.
-
-        if (entry == mfEntry) {
-            LOGV("Skipping manifest %.*s\n", fn.len, fn.str);
-        } else if (fn.len > 0 && fn.str[fn.len-1] == '/' && len == 0) {
-            LOGV("Skipping directory %.*s\n", fn.len, fn.str);
-        } else if (!strncasecmp(fn.str, "META-INF/", 9) && (
-                !strncasecmp(fn.str + fn.len - 4, ".RSA", 4) ||
-                !strncasecmp(fn.str + fn.len - 3, ".SF", 3))) {
-            LOGV("Skipping signature %.*s\n", fn.len, fn.str);
-        } else {
-            unverified[i] = true;
-            totalBytes += len;
+    const uint8_t* sha1 = SHA_final(&ctx);
+    for (i = 0; i < numKeys; ++i) {
+        // The 6 bytes is the "$ff $ff (signature_start) (comment_size)" that
+        // the signing tool appends after the signature itself.
+        if (RSA_verify(pKeys+i, eocd + eocd_size - 6 - RSANUMBYTES,
+                       RSANUMBYTES, sha1)) {
+            LOGI("whole-file signature verified\n");
+            free(eocd);
+            return VERIFY_SUCCESS;
         }
     }
-
-    unsigned doneBytes = 0;
-    char *line, *save, *name = NULL;
-    for (line = strtok_r(mfBuf, eol, &save); line != NULL;
-         line = strtok_r(NULL, eol, &save)) {
-        if (!strncasecmp(line, namePrefix, sizeof(namePrefix) - 1)) {
-            // "Name:" introducing a new stanza
-            if (name != NULL) {
-                LOGE("No digest:\n  %s\n", name);
-                break;
-            }
-
-            name = strdup(line + sizeof(namePrefix) - 1);
-            if (name == NULL) {
-                LOGE("Can't copy filename in %s\n", line);
-                break;
-            }
-        } else if (!strncasecmp(line, contPrefix, sizeof(contPrefix) - 1)) {
-            // Continuing a long name (nothing else should be continued)
-            const char *tail = line + sizeof(contPrefix) - 1;
-            if (name == NULL) {
-                LOGE("Unexpected continuation:\n  %s\n", tail);
-            }
-
-            char *concat;
-            if (asprintf(&concat, "%s%s", name, tail) < 0) {
-                LOGE("Can't append continuation %s\n", tail);
-                break;
-            }
-            free(name);
-            name = concat;
-        } else if (!strncasecmp(line, digestPrefix, sizeof(digestPrefix) - 1)) {
-            // "Digest:" supplying a hash code for the current stanza
-            const char *base64 = line + sizeof(digestPrefix) - 1;
-            if (name == NULL) {
-                LOGE("Unexpected digest:\n  %s\n", base64);
-                break;
-            }
-
-            const ZipEntry *entry = mzFindZipEntry(pArchive, name);
-            if (entry == NULL) {
-                LOGE("Missing file:\n  %s\n", name);
-                break;
-            }
-            if (!mzIsZipEntryIntact(pArchive, entry)) {
-                LOGE("Corrupt file:\n  %s\n", name);
-                break;
-            }
-            if (!unverified[mzGetZipEntryIndex(pArchive, entry)]) {
-                LOGE("Unexpected file:\n  %s\n", name);
-                break;
-            }
-
-            uint8_t expected[SHA_DIGEST_SIZE + 3], actual[SHA_DIGEST_SIZE];
-            int n = b64_pton(base64, expected, sizeof(expected));
-            if (n != SHA_DIGEST_SIZE) {
-                LOGE("Invalid base64:\n  %s\n  %s\n", name, base64);
-                break;
-            }
-
-            if (!digestEntry(pArchive, entry, &doneBytes, totalBytes, actual) ||
-                memcmp(expected, actual, SHA_DIGEST_SIZE) != 0) {
-                LOGE("Wrong digest:\n  %s\n", name);
-                break;
-            }
-
-            LOGI("Verified %s\n", name);
-            unverified[mzGetZipEntryIndex(pArchive, entry)] = false;
-            free(name);
-            name = NULL;
-        }
-    }
-
-    if (name != NULL) free(name);
-    free(mfBuf);
-
-    for (i = 0; i < mzZipEntryCount(pArchive) && !unverified[i]; ++i) ;
-    free(unverified);
-
-    // This means we didn't get to the end of the manifest successfully.
-    if (line != NULL) return false;
-
-    if (i < mzZipEntryCount(pArchive)) {
-        const ZipEntry *entry = mzGetZipEntryAt(pArchive, i);
-        UnterminatedString fn = mzGetZipEntryFileName(entry);
-        LOGE("No digest for %.*s\n", fn.len, fn.str);
-        return false;
-    }
-
-    return true;
-}
-
-
-bool verify_jar_signature(const ZipArchive *pArchive,
-        const RSAPublicKey *pKeys, int numKeys) {
-    const ZipEntry *sfEntry = verifySignature(pArchive, pKeys, numKeys);
-    if (sfEntry == NULL) return false;
-
-    const ZipEntry *mfEntry = verifyManifest(pArchive, sfEntry);
-    if (mfEntry == NULL) return false;
-
-    return verifyArchive(pArchive, mfEntry);
+    free(eocd);
+    LOGE("failed to verify whole-file signature\n");
+    return VERIFY_FAILURE;
 }
diff --git a/verifier.h b/verifier.h
index d784dce..1bdfca6 100644
--- a/verifier.h
+++ b/verifier.h
@@ -17,14 +17,14 @@
 #ifndef _RECOVERY_VERIFIER_H
 #define _RECOVERY_VERIFIER_H
 
-#include "minzip/Zip.h"
 #include "mincrypt/rsa.h"
 
-/*
- * Check the digital signature (as applied by jarsigner) on a Zip archive.
- * Every file in the archive must be signed by one of the supplied RSA keys.
+/* Look in the file for a signature footer, and verify that it
+ * matches one of the given keys.  Return one of the constants below.
  */
-bool verify_jar_signature(const ZipArchive *pArchive,
-        const RSAPublicKey *pKeys, int numKeys);
+int verify_file(const char* path, const RSAPublicKey *pKeys, unsigned int numKeys);
+
+#define VERIFY_SUCCESS        0
+#define VERIFY_FAILURE        1
 
 #endif  /* _RECOVERY_VERIFIER_H */